E852, Vol. 2 RUSSIAN FEDERATION

ROSTOV VODOKANAL AND ROSTOV OBLAST ADMINISTRATION

Grant for Preparation of the Project on Reduction of Nutrient Discharges and Methane Emissions in Rostov-on-Don

FINAL REPORT on

ENVIRONMENTAL IMPACT ASSESSMENT, PUBLIC AWARENESS AND EDUCATION

South-Russia Centre for Preparation and Implementation of International Projects (CPPI-S)

Rostov – on – Don 2004

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The Environmental Assessment Team The core team involved in the development of this EIA were:

Prof. A Khovansky, economics of nature management and environment management, sociology, social economy

Dr. L Kosmenko, hydrochemistry Mrs. I Mikheeva, health protection Prof. V Privalenko, environment protection Mrs. T Tarasenko, water supply and water abstraction Mr. E Ulshtein, technical planning and design Mrs. N Tsapkova, waste management

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Contents Contents 3 SUMMARY 6 Chapter 1 Background 7 Chapter 2 Explanatory Note 9 Chapter 3 Objective and needs in implementation of the proposed activity 10

3.1. Nutrient reduction in wastewater 10 3.2 Sludge Processing and Methane Utilisation 11 3.3. Dissemination Programme 11

Chapter 4 Description of alternative options to achieve stated objective 12 4.1. Existing system of wastewater treatment 12

4.1.1 Existing equipment and system of waste water treatment of the WWTP Phase I 12 4.1.2. Existing equipment and system of waste water treatment of the WWTP Phase II 13 4.1.3. Existing equipment and system of sludge processing 13 4.1.4 Current loading on the plant 14 4.1.5. Existing sludge volumes and quality 16

4.2 Planned activities on the WWTP reconstruction 18 4.2.1. Proposed volume and composition of wastewater 18 4.2.2. Standards of wastewater treatment 19 4.2.3 Planned content of the WWTP wastewater and technological scheme of wastewater and sludge treatment 21 4.2.4. Wastewater treatment models 25 4.2.5. Planned activities on sludge treatment 31 4.2.6 Upgrade of technical design of 2000 and step-by-step division of construction 40 4.2.7. Alternative options to achieve stated objective of the proposed activity44

Chapter 5. Description of possible environmental impacts for alternatives options45 5.1. Environmental Impacts at Present 47 5.2 Environmental Impacts during Construction 47 5.3 Environmental Impacts during Operation 49

Chapter 6 Relevant Environmental Legislation for Selected Options 60 Chapter 7. Description of Environmental Conditions 64

7.1 Natural conditions within the WWTP site 64

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7.1.1. Climate 64 7.1.2. Topography and hydrography 64 7.1.3. Hydrogeology and protection of ground water 66 7.1.4. Vegetation cover 66 7.1.5. Soils 67 7.1.6. Fauna 67 7.1.7. Specially protected areas 69

7.2. Social and economic situation 69 7.2.1. Demography 70 7.2.2. Population economic activity 70

7.3 Assessment of the current environment situation 71 7.3.1 Survey methodology 71 7.3.2. Surface water assessment 72

Chapter 8 Assessment of the proposed activity environmental impact 77 8.1 Air quality 77 8.2. Impact on surface water quality 85

8.2.1. Zero option – no reconstruction. 85 8.2.2. Option with biological treatment, wastewater advanced treatment and phosphorous chemical stripping 93 8.2.3. Option with nutrients reduction only with biological treatment of wastewater 95

8.3 Impact on ground water 96 8.4 Impact on soil and underlying rocks 96 8.5 Impact on vegetation and fauna 96 8.6 Impact of waste 96 8.7 Environmental conditions for project implementation 98

Chapter 9 Measures on mitigation and/or reduction of adverse environmental impact of the proposed activity 99

9.1 Proposals on mitigation of risks due to toxic gases emissions 99 9.2 Proposals on mitigation of adverse impact on the Lower Don aquatic ecosystems as a result of the WWTP reconstruction 99 9.3 Proposals on mitigation of risks associated with ground water pollution 99 9.4. Proposals on mitigation of risks associated with the WWTP sludge storage99

Chapter 10 Environmental consequences of possible emergency situations 101 Chapter 11 Uncertainties 102

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Chapter 12 Justification of selected option of the planned WWTP reconstruction103 Chapter 13 Public hearings on EIA and activities on environmental education and public awareness 104 Chapter 14 Environmental Management Plan 105

14.1 Mitigation Plan 105 14.2 Monitoring Plan 109 14.3 Training and Capacity Building Requirements 110 14.4 Social aspects of project implementation 110

Chapter 15 Dissemination Programme 111 Key conclusions 113 Annex 1 Minutes of the meeting of interested agencies and general public on Environment Management Plan 122 Annex 2 Protocol of the EIA public hearings 123 Annex 3 Project booklet (in Russian) 128 Annex 4 Project leaflet (in Russian) 130

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SUMMARY Present Report is prepared by specialists of the CPPI-S in accordance with the Contract No. 2 for consulting services on Environmental Impact Assessment, public awareness and education as part of preparation works of the Project on Reduction of Nutrient Discharges and Methane Emissions in Rostov-on-Don (GEF grant No. TF 027721). Report was prepared in compliance with the existing legislation and procedural requirements, juridical acceptable both for the Russian Federation and IBRD (World Bank). In particular, the Report is a basis for approval of the project by an authorized Russian authority (Ministry of Natural Resources) in compliance with the Law on State Expertise, as well as the Report meets the requirements of the World Bank OP/BP/GP 4/01 for category B projects. Report in Environmental Assessment meets the requirements of “regulations on assessment of environmental impact of the proposed activity in the Russian Federation” (May 16th, 2000, № 377). As part of the consulting services the following tasks were conducted by the CCPI-S to prepare the present Report:

Description of the environment status in the pilot area Analysis of legal documents in the sphere of environment management and

protection Identification of possible environmental impacts due to implementation of alternative

decisions of Rostov WWTP reconstruction. Development of Environment Protection Action Plan Promote co-ordination between agencies and public participation

English version of the Report is a slightly shortened Russian version of the EIA report with all important information preserved. It consists of 123 pages, 15 main chapters, 9 figures and 4 annexes. As on June 1st, 2004 based on materials prepared by SWECO International it was concluded that option of the WWTP reconstruction providing biological treatment, advanced treatment of waste water and phosphorus chemical removal with sludge compaction in methane tanks (digestion), collection and utilisation of methane on designed CHP plant is the most preferable in order to achieve waste water quality objectives.

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Chapter 1 Background The Government of the Russian Federation received proceeds from the Global Environmental Facility (GEF) in USD324,000 equivalent for implementation of the Project on Reduction of nutrient discharges and methane emissions in Rostov-on-Don. Grant beneficiary if the RF Ministry of Natural Resources and FCGC “Ecologiya” acted as the project Implementation unit (PIU) further referred as a “Customer”. The Project would consist of two sub-projects:

reduction of nutrient discharges, and reduction of methane emission.

The overall objective of this work is to assess environmental impact of the planned reconstruction of the Rostov Vodokanal wastewater treatment plant (WWTP) in compliance with the existing Russian legislation and requirements of the World Bank OP/BP/GP 4/01 for category B projects. In the Russian Federation the Law on State Expertise and “Regulations on assessment of the impact posed by the proposed activity on environment in the Russian Federation“ regulate the EIA requirements (2000). It is expected that trying to gain ToR objectives the following interrelated outputs will be achieved: (a) to provide Project’s approval by the Federal bodies responsible for the State Environmental Expertise; (b) to provide information to users and key stakeholders on improved waste water management practice, risks associated with the improper WWTW; and (c) to involve general public in implementation of project-support waste water management improvements, including possible replacement of phosphorous containing detergents by another types of detergents. According to the World Bank requirements EA Report should describe possible negative and positive impact and propose measures aimed at mitigation or reduction of the risk of pollution, compensation of adverse impact and improvement of environmental activities. Recommendations should be presented in a form of Environment Management Plan. Technical state of the works was described in three reports: Project on reconstruction of the Rostov WWTP is presented in a Feasibility Study: reconstruction of the Rostov WWTP (Phases I and II) (2000), report prepared by "JACOB-GIBB" (2003) and "SWECO INTERNATIONAL" (2004). The EIA is based on these reports. The Rostov WWTP works (Phases I and II) is located on the left bank of the River Don, within a floodplain, 3 km downstream railway bridge, opposite the Besymyanny Island, 100 m off the coastal line. Construction site of the Rostov port borders the WWTP site at north together with the Don River; WWTP Phase III construction site - from the south-east; pond of a fishing farm and Zarechnaya industrial zone - from the northeast; pond of a fishing farm, bituminous concrete plant and motorway Rostov-Bataysk - from the west and northwest. Normative sanitary-protection zone (SPZ) for thw WWTP is 1000 m (according to SanPiN 2.2.1/21.1.1200-03). Residential area locates on the right bank of the Don river, about 1200 m. A present amount of wastewater treated at the existing WWTP of Phases I and II is 313,000m3/day. The following are part of the WWTP:

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Mechanical treatment works: inlet camera; screen building; grit traps and primary settlement tanks.

Biological treatment works: aeration tanks; secondary settlement tanks; contact reservoirs.

Works for wastewater disinfecting: chlorination room with chlorine store; mechanical dewatering plant; sludge drying beds.

Supporting facilities: administrative building; boiler-house; blowing house; garage; mechanical plant; pumping stations for transfer of raw sludge, digested sludge, etc.; pumping station for transfer of treated wastewater to the don river.

The following scheme is used for wastewater treatment: wastewater from Rostov-on-Don, Bataysk and industrial enterprises is collected via two main tunnelled interceptors. Wastewater is transferred across the River Don to the East Bank via a syphon to the Main Pumping Station which pumps wastewater to the inlet camera. Then crude wastewater is screened to remove large floating objects. After that wastewater enters grit traps where mineral particles 0.2-0.25 mm size are settled. After grit traps wastewater enters primary settlers to settle mineral and organic suspended solids. After mechanical treatment wastewater enters aeration tanks and mixes with activated sludge in conditions of mandatory aeration. Here starts biological treatment of wastewater. Air is pumped into the aeration tanks. After aeration tanks wastewater enters secondary settlers. Their purpose is to separate activated sludge and treated water. Major part of organic matter of activated sludge is settled in secondary settlers. Liquid chlorine is added to wastewater for disinfecting purposes. It enters head conduits where treated wastewater contacts chlorine. Treated wastewater is piped to the outfall into the Don river by means of pumping station located at the WWTP site. Boiler-house locates at the WWTP site. It serves for heating purposes. There are gas three boilers in the boiler-house. Reserve fuel is not envisaged. There is a supporting space at site used for technical maintenance and current repair of equipment. EIA and implementation of recommendations presented in the Report should prove that studied project options are environmentally appropriate and sustainable; and that any environmental consequences were defined at an early stage of the project development and taken into account in the final project structure.

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Chapter 2 Explanatory Note Justification documentation for the project are:

Feasibility Study: reconstruction of the Rostov WWTP (Phases I and II) developed by the Designed Institute North-Caucasus GiprokommunVodokanal in 2000;

In 2001 Halcrow Group Ltd. developed “Strategic Plan and Short Term Investment Plan for the Municipal Water Services of the City of Rostov-on-Don” and “Reduction of Nutrient Discharges and Methane Emissions in Rostov-on-Don. Environmental Impact Assessment”;

"JACOB-GIBB" together with Helsinki Consulting Group both responsible for Joint Environmental Programme JEP-II conducted Project Feasibility Study;

By competitive bidding Rostov Regional Foundation for Social Projects (RRFSP) has awarded SWECO INTERNATIONAL in cooperation with North-Caucasus Giprokommunvodokanal to elaborate the Process Design Report and the technical Project for the task.

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Chapter 3 Objective and needs in implementation of the proposed activity Project long-term objective is to reduce euthrophication level of the Azov abd Balck seas through reduction of nitrogen and phosphorous discharges and greenhouse gases emissions. Project goals:

Reduction of nutrient (nitrogen and phosphorous) discharges into the Don River through rehabilitation and improvement of the wastewater treatment at Rostov WWTP of Municipal Water and Wastewater Company (Rostov Vodokanal, RVK)

Reduction of wastewater sludge and reduction of organic matter in wastewater through the Rostov WWTP sludge digestion and dewatering.

Reduction of methane emissions from the Rostov WWTP sludge through methane gas capture and combustion and usage of collected methane for electric power generation and heat utilization.

Development of a Programme for dissemination of experience on reduction of nutrient discharges and methane emissions at municipal enterprises in other regions of Russia and possibly to the countries of the Azov-Black sea basin.

3.1. Nutrient reduction in wastewater The objective for nutrient removal is to reduce nutrient levels in the effluent by the following: total phosphorus - 60% reduction, nitrogen - 50% reduction. In the long-term the works will eventually need to be improved, to ensure compliance with the following stringent Russian Discharge Consent:

BOD 3 mg/l Suspended solids 3 mg/l Total Nitrogen 9 mg/l Phosphorus 0.3 mg/l

Activities on nutrient removal include reconstruction and reequipping of the existing technological tanks and constructions of the WWTP Phase II. Primary settlers of the WWTP Phase II are extremely depreciated; scrapers need reconstruction and replacement. At present it is recommended to keep pre-aeration and equipment for activated sludge pumping. Activities on reconstruction of the existing aeration tanks will be minor. Dispersants and air-blowers will be replaced; number of aerators will be increased. Lines will be repaired in turns to provide constant capacities for wastewater treatment. Wastewater will be treated in three phases: an anaerobic (preparing bacteria for phosphorus removal in later stages of the process), an anoxic stage (nitrates are reduced) and an aerobic (absorption of ammonia and phosphorus by bacteria). Existing secondary settlers will be provided with lamella separators and bioreactors (filters with brush loading). Bioreactors will be added to reconstructed WWTP Phase I. Inclusion of filters with brush loading is necessary for additional treatment to comply to Russian norms for discharges into water bodies.

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Required reduction of phosphorous in treated wastewater could be achieved using biological treatment. However, in anaerobic conditions phosphorous absorbed by sludge will be then evolved into solution. Thus, chemical treatment will be required for sludge water generated in conditions of sludge dewatering. Sludge after dewatering will be disposed to sludge-heaps. 3.2 Sludge Processing and Methane Utilisation Decreased of sludge volume (and amount of sludge required disposal) will be due to digestion of compacted sludge in 6 new methane tanks; due to compaction of sludge in the existing sludge thickeners and sludge dewatering in three new centrifuges. Sludge water will be transferred to the works head. Before a proper strategy will be developed sludge will be stored in sludge drying beds or in sludge storage lagoons. Centrifuges were installed and put into operation. They can produce sludge with content of 30% dry matter. Reduction of sludge volume depends on type of methane and operation regime and can be up to 50% of the existing volume. Methane generates in conditions of bacteriological sludge digestion. Entering the Earth atmosphere it contributes into “greenhouse effect” (greenhouse gases). One of the key objectives is to generate electric and thermal energy as a result of utilization of methane accumulated in methane tanks. Electric energy generation at site will significantly reduce amount of gases emitted into the atmosphere (in terms of CO2) and will result in costs savings for Rostov Vodokanal. Purchase of equipment and construction of combined heat plant (CHP) is part of activities. CHP will be used for provision of digestion and dewatering processes with energy (electric and thermal). Both processes are power consuming. Heat from used gas will be transferred into vapour for sludge heating and water used for cooling will be abstracted directly to the central heating system. 3.3. Dissemination Programme Programme for dissemination the Rostov Vodokanal experience in countries of the Azov-Black sea basin includes the following: 1. Environmental actions to popularize and disseminate information about Project’s outputs and achievements in towns and cities of the Azov-Black sea basin (preparation and publication of the brochure with description of key Project outputs, mobile exhibition or participation in environmental exhibitions in the coastal cities and towns, meetings with Administrations and Vodokanals of the coastal cities and towns). 2. Training and raising the level of specialist’s skills in the sphere of water supply and water abstraction. 3. Public campaign in mass media. Towns and cities for results dissemination: in Russia – Azov, Taganrog, Novorossiisk, Sochi; in Ukraine – Mariupol, Nikolaev, Sevastopol, Odessa; in Georgia – Batumi; in Bulgaria – Varna, Burgas; in Romania – Konstansa; in Turkey – Samsun. The ToR for the Programmme of results dissemination developed by the CPPI-S is part of the present Report.

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Chapter 4 Description of alternative options to achieve stated objective 4.1. Existing system of wastewater treatment The wastewater treatment plant (WWTP) is located on the left bank of the River Don in Zarechnaya industrial area of the city. The majority of wastewater from Rostov-on-Don is transported across the River Don to the WWTP via the Main pumping station (PS). In addition, wastewater is pumped directly to the WWTP from the "Gnilovckaya" PS, which serves western areas of the city. Wastewater from the town of Bataysk, which lies to the south, is also delivered to the WWTP. The Rostov WWTP comprises two almost identical treatment streams (Phases I and II). The site includes areas leaving room for a major extension of the plant, if found necessary. It will be twice of the existing capacity. Activities on the WWTP extension started several years ago but then was paused due to lack of funding. There are no plans for recommencement of the WWTP Phase III. 4.1.1 Existing equipment and system of waste water treatment of the WWTP Phase I Existing equipment of the WWTP Phase I includes: screens; grit traps, reservoirs of the first step (pre-aeration), primary settlement tanks, aeration tanks, secondary settlement tanks, bioreactors, reservoir for chlorination, compressor house. Screens. Five hydraulically inclined curved 16 mm screens are installed for large particles screening. Timers control screens operation. Screenings are fed to the fly press to remove excess water. Residual particles are placed at sludge heaps. Grit traps. There are 4 grit traps each 17.7 m long and 1,25 m deep. Screenings are removed using scrapers towards bunker at the grip traps head. From there sand with water is raised and then removed and disposed at sand beds. Reservoirs of the first step. Phase I has 4 identical technological tanks. Preliminary treated wastewater enters aeration chambers 6.0 m wide and 4.4. m deep. Activated sludge is returned to a pre-aeration tank but only in conditions of high incoming load. Primary settlement tanks. Each technological line has four rectangular settlement tanks (27 m long, 9 m wide and 4.25 m deep). Scraper transporters near basemen feed settled sludge towards one end of a reservoir. Under hydraulic pressure head sludge enters pumping station of primary sludge for further transfer to sludge thickeners. Aeration tanks. Each aeration tank has 4 corridors for sludge mixture aeration. Each tank has size 9 m wide, 75 m long and 4.7 m deep. Porous aerators locate in each corridor. Air is supplied along steel distribution pipeline from air-blowing station. Air volume supplied to aeration tanks is manually controlled. Two sections of aeration tanks were reconstructed and now third section is under reconstruction. Secondary settlement tanks. Secondary settlement tanks were reconstructed using lamella separators. They are 11 m long. Activated sludge is removed by means of airlifts and then it is returned to aeration tanks. Surplus activated sludge is removed from system, if necessary, to support its concentration in aeration tanks. Bioreactors (brush filters). In two reduction conveyers effluents from secondary settlement tanks are additionally processed in biologically aerated filter in a form of upstream. In this device “environment” consist of small brushes on which biomass

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develops. They provide biological treatment and filtration. Filters need backwashing twice a week. This is air washing under increased flow velocity in four times. Reservoir for chlorination. After mechanical and biological treatment wastewater is chlorinated in a reservoir for chlorination in compliance with Russian requirements. Compressor house. In a compressor house there are six compressors with capacity 750 m3/minute, pressure 0.06 MPa and engines with power 1250 kWt. Compressors are cooled with water. Usually three compressors are used to serve aeration tanks of Phases I and II. 4.1.2. Existing equipment and system of waste water treatment of the WWTP Phase II Equipment of the WWTP Phase II is similar to equipment of Phase I, except for bioreactors. Screens. Five hydraulically inclined curved 16 mm screens are installed for large particles screening. Screenings are fed to the fly press to remove excess water. Grit traps. Grit traps of the Phase II are aerated. But process of sand removal is similar to Phase I. Reservoirs of the first step. Phase II has 4 identical technological tanks. Preliminary treated wastewater enters aeration chambers Primary settlement tanks. Each technological line has four rectangular settlement tanks (27 m long, 9 m wide and 4.25 m deep). Scraper transporters near basemen feed settled sludge towards one end of a reservoir. Under hydraulic pressure head sludge enters pumping station of primary sludge for further transfer to sludge thickeners. Scrapers for one line were repaired and now only one line operates. Other lines are in a bad condition or out of service. Aeration tanks. Each aeration tank has 4 corridors for sludge mixture aeration. Each tank has size 9 m wide, 75 m long and 4.7 m deep. Nets of porous tubular diffusers locate on each line. Air from a compressor house is supplied along steel distribution pipeline. Pipeline and diffusers are in a bad condition with leaking and breaks. Secondary settlement tanks. Secondary settlement tanks are 30 m long. Width of each four lines is 9 m. Scrapers locate near baseman. Activated sludge is removed by means of airlifts and then is returned to aeration tanks. Surplus activated sludge is removed from system, if necessary, to support its concentration in aeration tanks. Reservoir for chlorination. After mechanical and biological treatment wastewater of the Phase II is chlorinated regardless effluents of Phase I. But before discharge into the Don river they are mixed. 4.1.3. Existing equipment and system of sludge processing Equipment for sludge processing includes: sludge thickeners, building with centrifuges, reservoirs for sludge digestion, sludge drying beds. Sludge thickeners. There are four radial sludge thickeners (18 m diameter and 3.5. m deep). Sludge from primary settlement tanks and surplus activated sludge is thickened. Mixture moisture is 94-98%. In summer after addition of flocculating agent thickened sludge is transported to sludge drying beds for storage. In winter thickened sludge is

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transported to building with centrifuges. Building with centrifuges. Three Humbolt centrifuges, buffer storage, polyelectrolyte systems of mixing and dosing, pumps supplying sludge, conveyers for dewatered sludge locate in the building. Here moisture of dry solid matter is 28-30%. Reservoirs for sludge digestion (methane tanks). There are two anaerobic reservoirs for sludge digestion. Both are out of service. Also two reservoirs are still under construction. Sludge drying beds. Sludge drying beds have concrete foundation, asphalted in inclined sections used for liquid drainage through drainage system backwards to the inlet of the second line. There are 31 sludge drying beds each 90 x 40 m with nominal depth of 1 m. Walls are concrete. In summer beds are filled by means of pumps and are cleared by a loader when sludge reaches moisture content of 70%. 4.1.4 Current loading on the plant Existing average discharge of wastewater required treatment is about 292,000 m3/day varying between 280,000 and 310,000 m3/day. Daily peak discharge is more than 360,000 m3/day. This amounts to 10-20% increase in conditions of damp weather. During reconstruction works at the Phase I inflow to this technological line lies within 100,000-160,000 m3/day; Phase II receives remaining amount of 140,000 – 180,000 m3/day. Data on flows to the WWTP for the first six months of 2003 are given in Table 4.1. Characteristics of untreated wastewater inflow to the WWTP for the last 2,5 years are given in Table 4.2 together with average daily pollution loads. Data is based on data about average flows in years 2001, 2002 and 2003 (309,000, 291,200 and 292,300 m3/day, respectively). Average characteristics of treated wastewater from the WWTP Phase I and II for 2001, 2002 and first six months of 2003 are given Table 4.3. Recent studies of wastewater from the WWTP Phase I (including lines under reconstruction) and from the WWTP Phase II are given in Table 4.4. The WWTP Phase I provides higher treatment level. Lower values of BOD5, ammonia and suspended solids concentrations prove this.

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Table 4.1 Flows to the WWTP for the first six months of 2003, m3/day

Phase I Phase II Combined Month

Maximum Minimum Average Maximum Minimum Average Estimated Maximum

Estimated Minimum

Average

January 143,963 73,446 97,492 206,654 127,584 183,142 317,000 229,000 280,634

February 153,444 85,998 128,795 196,848 150,970 176,156 3 4 8 , 0 348,000 304,951

March 156,560 98,074 129,996 182,138 123,761 158,129 338,698 228,000 288,125

April 207,368 136,352 159,975 201,902 nr 150,000 362,000 290,000 309,975

May 161,886 120,539 143,565 170,590 54,749 141,957 311,000 195,000 285,522

June 139,220 73,371 100,603 208,397 114,163 178,816 344,000 344,000 279,419

Ave. for 6 months 160,407 97,963 126,738 194,422 114,245 164,700 336,783 245164,7 291,438

Notes:

1. Minimum flows can be affected by pumping station break downs.

2. The combined maximum and minimum flows are estimated as the recorded maximums and minimums for Phases I and II do not necessarily occur on the same day. (Source: Information supplied by RVK)

Positive effect of reconstruction of Phase I is illustrated in Table 4.5 that gives the effluent results for reconstructed line 3. Wastewater flow has good treatment level with very low COD value (10 mg/l after bioreactor) and low level of suspended solids. In reconstructed aeration tanks nitrification is better. However, lack of denitrification capacities is obvious. Table 4.2: Wastewater characteristics and loads, 2001 - 2003

Concentration, mg/l Pollution load, kg/day Parameter

2001 2002 2003*) 2001 2002 2003*) BOD5 146.8 181.2 143.7 45,363 52,760 42,004 COD 312.5 91,345 Suspended Solids 175.1 211.3 219.9 54,108 61,524 64,277

Ammonia as N 16.08 15.7 16.8 4,969 4,571 4,911 Nitrite as N 0.04 0.07 0.05 12 20 15 Nitrate as N 0.1 0.12 0.135 31 35 39 Phosphates as P 1.83 1.38 1.77 565 402 517

Notes: data for the first six months of 2003. (Source: Information supplied by RVK) Table 4.3 Average treated effluent characteristics

Annual average concentration, mg/l

Annual average load discharged, kg/day

Parameter

2001 2002 2003 2001 2002 2003 BOD5 28.5 27.4 20.8 8,807 7,978 6,080COD n. a. n. a. 46.3 n. a. n. a. 13,534Suspended Solids 35.05 31.4 24.4 10,831 9,143 7,132Ammonia as N 4.54 2.6 2.7 1,403 757 789

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Nitrite as N 0.52 0.61 0.48 161 178 140Nitrate as N 1.55 2.17 2.49 479 632 728Sum N 6.61 5.38 5.67 2,043 1,566 1,657Phosphates as P 1.29 0.91 1.15 399 265 336

Table 4.4 Treated wastewater characteristics for Phases I and II, first half year 2003 results

Concentration, mg/l Parameter Phase I Phase II

BOD5 24.0 36.8COD 38 48Suspended Solids 30.0 39.5

Ammonia as N 2.39 3.45Nitrite as N 0.36 0.24Nitrate as N 4.4 3.02Phosphates as P 1.35 1.40рН 7.68 7.68Temperature, °С 26.6 26.5

Table 4.5 Treated wastewater characteristics for line 3 of Phase I

Concentration, mg/l Parameter

After secondary settlement tank

After biorecator

COD 25 10Suspended Solids 15.6 15.2

Ammonia as N 1.95 1.12

Nitrite as N 0.35 0.41Nitrate as N 5.03 6.25Phosphates as P 1.35 1.40

рН 8.16 7.91

4.1.5. Existing sludge volumes and quality At present total amount of produced sludge consists of 1220 m3/day primary sludge and 1355 m3/day surplus activated sludge. Sludge is pumped to drying beds and transported to sludge storage lagoons. Sludge from primary settlement tanks has a moisture content of 95-96%, surplus activated sludge is more than 96%. There are 31 sludge drying beds each 90 x 40 m with nominal depth of 1 m. Walls are concrete. Sludge drying beds have concrete foundation, asphalted in inclined sections used for liquid drainage through drainage system. Walls are made of uncovered concrete. On average drying bed bottom locates 3.76 m below average level of the Don

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river. Beds are consecutively filed by means of pumps and are emptied using frontal loader when content of moister reaches 70%. Sludge retaining time is 1 year. Each year 12-14 beds are emptied. Average moisture content in dried sludge is 77%. Sludge removed from sludge drying beds is stored at site with total area of 40,000 m2. A small but unknown quantity of sludge removed from the drying beds is used in City parks. Neither of this uses result in deceleration of sludge storage, which at present has reached its maximum. Sludge storage lagoon used from mid-1980-s for sludge removal is located in foundation pit formed due to sand recovery during the WWTP construction. In 1984 dam was constructed around pit filled with water. It formed closed lagoon for sludge storage. Initially dam was 2.5 m higher than bottom level and was constructed from mixture of clay and sand. Bottom level locates on the Don river average level. Lagoon design envisaged organization of clay substrate but no data were found about organisation of the substrate. In 1944 dam height was raised up to 3.5 m above bottom level and according to project drawings drainage pipes were laid through this extension to ensure pumping of supernatant liquid back to the outlet. The pipes are not in operation anymore and at present time water level inside the lagoon is 3 m above the bottom level. Bottom topography is not described but it was estimated that closed area is 28 hectares of which 30% have form of islands. Thus, lagoon’s capacity was assessed as 0.7 million m3. The second slightly larger lagoon adjoins to the first lagoon. Initially the second lagoon was not envisaged for sludge storage but it contains sludge partly due to leakage through non-engineering barriers between two lagoons. Key limitation for use of wastewater sludge for land reclamation is concentration of toxic substances and helminthes. However, toxic substances concentrations in the Rostov WWTP sludge gradually decreased due to decrease of industrial effluents. Wastewater sludge mechanically dewatered or dried at drying beds and kept in natural conditions for not less than 2 years has moisture content of 54-58%. This is low-hazard waste (class IV danger) due to increased concentrations of heavy metals (zinc, chromium, copper, nickel, lead). Pathogens (including salmonella and helminthes ova) were not found. In 2004 scientific company “BIFAR” (Moscow) assessed quality and quantity of sludge sampled in January 2004 from the WWTP site. For sludge passports were drawn. “Environmental certificates” were received for sludge of the municipal wastewater and their compliance with the following legal documents: “Criteria for attributing of hazardous waste to classes of danger for environment” (adopted by the RF Ministry of Natural Resources No. 511 dated 15.06.01); GOST P 17.4.3.07-2001 “Nature protection. Soil. Requirements to wastewater sludge if used as fertilizers”; SanPiN 2.1.7.573-96 “Hygienic requirements to use of wastewater and their sludge for irrigation and as fertilizer”; SP 2.1.7.1038-01 “Hygienic requirements to organisation and management of MSW landfills” (Annexes 1-4). Content of organic matter varies in sludge (in terms of dry matter) in a range of 45-47%, total nitrogen – 3.2-2.5%, phosphorous (in terms of Р2О5) – 3.5–3.4%, lead – 45-48 mg/kg, cadmium – 5.8-9.4 mg/kg, copper – 123-124 mg/kg, nickel – 62.6-71.6 mg/kg, zinc – 800-832 mg/kg, chromium - 352-375 mg/kg, manganese – 104-109 mg/kg, mercury – 0.1-0.5 mg/kg, arsenic – 7.8-9.3 mg/kg. At the end of March 2004 amount of dewatered sludge disposed at the WWTP site was 25.59 thousand tons (in terms of dry matter) of which 24.46 thousand tons were

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disposed on sludge drying beds and 1.13 thousand tons at landfill for temporary sludge storage. As sludge gets dried it is transported from drying beds and is use for reclamation works at site of the WWTP. 4.2 Planned activities on the WWTP reconstruction 4.2.1. Proposed volume and composition of wastewater Different estimations on the future flows and pollution loads have been presented. The Study from 2000, Technical Process Design Report -Rehabilitation of Wastewater Treatment Plant in Rostov-on-Don (I and II Stages), suggests an increase of the design flow to 460,000 m3/day, along with increased pollution loads. The report has been approved and as such the figures will be used as one target ground for the process analysis and assessment of technologies for the upgraded Rostov WWTP. In the JACOB-GIBB report a revised projection of wastewater amounts and pollution levels are presented, along with an "Expected Short Term Loads" situation. Corrected parameters for different flows and loads are given in Tables 4.6 – 4.6a (SWECO INTERNATIONAL, 2004). For the following assessment of different process options the following flow and pollution load situations will be addressed:

A. Expected Short Term Loads, with Q = 332,000 m3/d, and BOD5 load = 52,908 kg/day;

B. Revised2025 Loads, with Q = 360,000 m3/d, and BOD5 load = 70,656 kg/day;

C. Design Institute Loads, with Q = 460,000 m3/d, and BOD5 load = 105,800 kg/day;

Table 4.6 Estimations of current and future loads entering Rostov WWTP

Parameter Current loads

Expected short term loads

Revised 2025 loads

Design Institute loads

Design flow, m3/d 292,300 332,000 360,000 460,000

Anticipated loads

BOD5, kg/d 42,004 52,908 70,656 103,040

Total suspended solids, g/d 64,277 66,014 79,557 138,000

Ammonia Nitrogen, kg/d 4,911 6,836 9,134 10,120

Total Phosphorus*, kg/d 1,034* 1,781 2,409 4,416

Anticipated concentrations

BOD5, mg/l 144 159 196 230

Total suspended solids, mg/l 220 199 221 200

Ammonia Nitrogen, mg/l 16.8 20.6 25.4 22.0

Total Phosphorus*, mg/l 3.5 5.4 6.7 9.6

Note: *Total phosphorus taken as twice phosphate load.

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Table 4.6a Designed discharges and load of wastewater on the Rostov WWTP (SWECO, 2004)

Data on pollution and discharge

Short-term For 2005 Long-term Unit

Discharges of wastewater at the works head Daily average amount 330000 360000 460000 m3/dayHourly average amount 13750 15000 19167m3/hourPeak capacity of pumping stations 424246 464000 464000 m3/dayDesigned flow per hour, estimates 13833 15000 20500m3/hour

Peak flow, estimates 17677 19333 27605m3/hour

Pollutants loads BOD5 42,389 70,656 105,800 t/dayCOD (allowable value) 84,778 141,312 211,600 t/day

NH4-N 6,836 9,134 10,120 t/day

Nitrogen total 9,092 12,149 13,460 t/day

Phosphrous total 1,781 2,409 4,416 t/day

Suspended solids 66,014 79,557 92,000 t/day

Suspended solids /BOD5 1.56 1.13 0.87 kg/kgBOD5/Nitrogen 4.66 5.82 7.86 kg/kg

BOD5/Phosphorous 23.8 29.3 24.0 kg/kg

Concentrations BOD5 128 196 230 mg/lCOD (allowable value) 257 393 460 mg/l

NH4-N 21 25 22 mg/l

Nitrogen total 28 34 29 mg/l

Phosphrous total 5 7 10 mg/l

Suspended solids 200 221 200 mg/l

Minimal and designed temperature 16/20 16/20 16/20 oC

4.2.2. Standards of wastewater treatment Existing Russian effluent standards for the WWTP formally defined in compliance with SniP are given in table 4.7. Table 4.7 Existing effluent standards according to SNiP norms

Determinant Consent value BOD5 < 3 mg /lSuspended Solids < 3 mg /lAmmonia nitrogen < 0.39 mg/l

Nitrite nitrogen 0.02 mg/lNitrate nitrogen 9.1 mg/l

Total Nitrogen < 9.42 mg/l

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Phosphates (P2O5) < 0.61 mg/lPhosphorus (as P2O5-P) < 0.2 mg/l

As already underlined these standards are in many respects far more stringent than the ruling consent values for the European Union, defined by the Directive EEC 91/278, stating the following values (Table 4.7a). Table 4.7a Existing effluent standards according to Directive EEC 91/278

Determinant Consent value

BOD5 < 25 mg /lSuspended Solids < 35 mg /lTotal Nitrogen < 10 mg/lPhosphorus (as total P) < 1.0 mg/l

The following over all demand for the treatment performance has been defined as the ruling GEF objectives for nutrient removal at the Rostov WWTP:

Total phosphorus - 60% reduction in the effluent; Nitrogen - 50% reduction in the effluent.

The given definition on effluent demands is however not undisputable. Two ways of understanding the statement of the required reduction may be addressed: 1. The JACOB-GIBB report interprets the given definition as follows:

The reduction of P would result in an effluent level of about 2.5 to 3 mg P/l according to the same philosophy.

The reduction of N would result in an effluent level of about 8 mg N/l, taking into account that the influent concentration is about 16 mg N/l.

The need for further reduction of P would not be necessary, as the current discharge levels seem to be < 2.0 mg total P/l.

The need for further reduction of N would not be necessary, as the current discharge levels seem to be < 8.0 mg total N/l.

2. The other obvious interpretation of the definition is that the demand for further reduction in the effluent is related to the current levels of P and N discharges. This in turn would result in the following:

The reduction of P would result in an effluent level of about 0.7 to 1 mg P/l, taking into account that the current effluent concentration is about 1.5 - 2 mg N/l.

The reduction of N would result in an effluent level of about 3 - 3.5 mg N/l, taking into account that the current effluent concentration is about 6 - 7 mg N/l.

The need for further reduction of P would call for a chemical P removal, as the demanded effluent levels would be very hard to achieve by biological P removal only. The target value for the P level in the effluent will come rather close to the Snip value of 0.2 mg P (PO4-P)/l

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The need for further reduction of N would call for an excellent nitrification at all circumstances and also possibly the addition of external organic carbon, as the discharge would become very hard to achieve with the available organic carbon in the wastewater only. It should be observed that the Snip norm calls for a total N < 9 mg/l.

According to recommendation prepared by SWECO INTERNATIONAL the ultimate target values for the treated wastewater from the Rostov WWTP will be in accordance with SNiP norm, but they will be modified by the intermediate effluent level on nitrogen. For intermediate phase of the WWTP reconstruction the following parameters will be used for treated wastewater (see Table 4.8): Table 4.8 Adopted intermediate treated wastewater standards for the Rostov WWTP

Determinant Consent valueBOD5 < 15 mg/lSuspended Solids < 25 mg /lAmmonia nitrogen < 0.39 mg/lNitrite nitrogen 0.02 mg/lNitrate nitrogen 2.5 mg/lTotal Nitrogen < 3 mg/lPhosphates (P2O5) < 1.95mg/lPhosphorus (as P2O5-P) < 0.65 mg/l

A way to analyse the different treatment options with respect to "Environmental Efficiency" is to apply the "OCP- value". "OCP" means Oxygen Consumption Potential, and was presented by H. 0degaard, at the Norwegian Technical University, Trondheim, Norway. This method to analyse a discharge of treated wastewater makes it possible to calculate oxygen consumption in a receiving body caused by the effluent from a treatment plant. Oxygen consumption in receiving water is often caused by both primary oxygen consumption (bacterial degradation of BOD and ammonia) and secondary oxygen consumption (bacterial degradation of algae caused by phosphorus and nitrogen). The calculation of OCP is based on the following ratios:

1 kg BOD results in 1 kg in primary oxygen consumption. 1 kg Tot-N results in 4 kg in primary oxygen consumption. 1 kg Tot-P results in 100 kg in secondary oxygen consumption. 1 kg Tot-N results in 14 kg in secondary oxygen consumption.

By using the OCP valued it is possible to express the amounts of BOD, nitrogen and phosphorus in the effluent from a treatment plant in one common unit. Although OCP is a simplified measuring tool it is a proper tool to assess the plant efficiency. OCP model was used to assess the Rostov WWTP efficiency. 4.2.3 Planned content of the WWTP wastewater and technological scheme of wastewater and sludge treatment Approved capacity of the WWTP is 460,000 m3/day. However, due to amount of investments gradual change of the WWTP capacity is required. At the

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intermediate phase it will be 360,000 m3/day. According to the required capacity of the WWTP, treatment level and method and based on SWECO’s recommendations and approved Technical Process Design Report -Rehabilitation of Wastewater Treatment Plant in Rostov-on-Don (I and II Stages) (1998), WWTP Phases I and II are envisaged in the following composition: Phase I works: А.1 Mechanical treatment works: 1. Reception (inlet) chamber 2. Screen building (reconstruction) 3. Horizontal grit traps 4. Pre-aerators – primary settlement tanks B.1 Biological treatment works: 1. Aeration tanks (reconstruction with identification of anoxic zone – denitrificator and aeration zone - nitrificator). 2. Secondary horizontal settlement tanks. C.1 Works for wastewater advanced treatment (1 stage) 1. Bioreactor with immobilized microflora. 2. Reservoir of dirty washed water. Phase II works: А.2 Mechanical treatment works: 1. Reception (inlet) chamber 2. Screen building (reconstruction) 3. Aerated grit traps 4. Pre-aerators – primary settlement tanks (reconstruction) B.2 Biological treatment works: B.2 Biological treatment works: 1. Aeration tanks (reconstruction with identification of anoxic zone – denitrificator and aeration zone - nitrificator). 2. Secondary horizontal settlement tanks (reconstruction). C.2 Works for wastewater advanced treatment (1 stage) 1. Bioreactor with immobilized microflora (reconstruction of the secondary settlement tanks) 2. Reservoir of dirty washed water (designed). C.3 Works for wastewater advanced treatment (2 stage) Phases I and II 1. Reception (inlet) chamber (reconstruction)

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2. Entrance chamber (designed) 3. Filters of advanced treatment (reconstruction) 4. Pumping station for advanced treatment filters (reconstruction). 5. Reservoir for washing water (reconstruction). 6. Filters media storage facility (reconstruction). 7. Aerator trough (aeration tank) (reconstruction, designed). D. Facilities for wastewater disinfection, Phases I and II Chlorination room with chlorine store and later station of UV- disinfection. E. Outlet of treated wastewater 1. Pumping station No. 4 for treated wastewater. 2. Discharge of treated wastewater from pumping station to dispersing outlet. 3. Dispersing outlet into the Don river. F. Facilities for sludge processing, Phases I and II 1. Gravel bunkers (extension) 2. Hydrolyzer (existing sludge thickeners D=18 m) 3. Sludge thickeners (reconstruction). 4. Methane tanks (reconstruction, designed). 5. Reservoir for mixture of sludge from primary settlement tanks and compacted excessive sludge (designed). 6. Heat exchanger building (designed). 7. Gas-holders (designed). 8. Methane tanks pumping station (designed). 9. Sludge dewatering plant (existing). 10. Emergency sludge drying beds (existing). 11. Storage place for dewatered sludge (existing). 12. Sand beds (existing). 13. Site for mixing wastewater with humin-mineral concentrate, and storage facility (designed). 14. Storage place for humin-mineral concentrate (reconstruction). J. Supporting buildings and facilities 1. Blowing house (reconstruction). 2. Pumping station No. 1 (reconstruction). 3. Pumping station No. 2 (reconstruction). 4. Pumping station in passes of capacity blocks of Phase II (reconstruction). 5. Pumping station of sludge thickeners (reconstruction).

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6. Reservoir for compacted excessive sludge (designed at pumping station of methane tanks). 7. Reservoir of sludge water. 8. Reagent storage building (new construction). 9. Storage facility for dry store of reagents. 10. Administrative building (existing). 11. Garage (existing). 12. Car wash (existing). 13. Repair and engineering workshops (existing). Site communications The following technological scheme of wastewater treatment is recommended (recommendations of JACOBS GIBB and SWECO INTERNATIONAL): Rostov and Bataysk wastewater are pumped to the inlet cameras of screens building of Phases I and II. Tiered 3-5mm Rotoscreen screens (MEVA company) are installed to prevent large floating solids arriving with wastewater. After separation from floating solids wastewater enters horizontal and aerated grit traps for precipitation of mineral suspended matter with hydraulic size of 24.2 mm/sec and 18.7 mm/sec. After grip traps wastewater enters horizontal settlement tanks to settle organic and mineral suspended solids. Phosphorous chemical stripping is envisaged to meet modern requirements to residual content of phosphorous in treated wastewater. For this it is planned to enter water solutions of reagents in trough before pre-aerators. Aluminium sulphate will be used as a key reagent (dose of 80-20 mg/l). After mechanical treatment wastewater enters biological treatment works with nitri-denitrification. For this two zones are established in the existing aeration tanks: anoxic (denitrificator) and aeration (nitrificator). Wastewater and return activated sludge from secondary settlement tanks (circulating), and sludge mixture from nitrificator are supplied to anoxic zone. Project envisages possible supply of sludge from hydrolyzers to the denitrification zone if amount of organic substrate is insufficient. Propeller mixers with submerged electric engines mix sludge mixture in anoxic zone. Reduction of nitrogen occurs in anoxic zone by means of activated sludge microflora. Sludge mixture spills from anoxic zone to aeration zone. Oxidation of organic matter and ammonia nitrogen into nitrates occurs in conditions of intensive air blowing supplied from air-blowing station. After aeration zone sludge mixture is collected by troughs and further is discharged into secondary horizontal settlement tanks. Installation of lamella separators is planned to improve capacity of secondary settlement tanks and sampled water quality. After secondary settlement tanks wastewater with residual concentration of suspended solids and organic matter (BOD total) of about 15 mg/l enters

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advanced treatment works. Two-phase advanced treatment is adopted. First phase is bioreactor with immobilized microflora consisted of subsequently operating stages. Each stage of bioreactor includes chamber for water enrichment with oxygen equipped with air distributor and reactor filled with brush feeding. Treated water enriched with oxygen in a saturation chamber passes through the brush feeding which form homogeneous porous space with pore sizes ensuring formation of bulk structures of activated sludge flake. Treated water saturated with oxygen is filtered through activated sludge flake. Biofilm develops due to a developed surface. Biocenose actively participates in extraction of organic pollutants from wastewater and in oxidation of ammonia nitrogen. Second phase (on a basis of reconstructed wire-charging filters) is a filter with granular loading. There water is treated by means of bottom-up filtration through sand feeding. After bioreactor washed water in the form of activated sludge flake enters reservoirs and then is transferred into anoxic zone (denitrificator). Washed water after filters rinsing is collected in reservoirs and there it is pumped to the works head. After advanced treatment wastewater is piped to an aeration through for saturation with oxygen by means of mechanical aerators. Adopted way of treatment will ensure following parameters:

suspended solids – 3 mg/l; organic matter (BODtotal) - 3 mg/l; ammonia nitrogen — 0.39 mg/l; nitrite nitrogen – 0.02 mg/l; nitrate nitrogen – 9.1 mg/l phosphates in terms of phosphorous – 0.2 mg/l.

Disinfection is the last phase of wastewater treatment. Liquid chlorine for disinfection is entered directly into head conduits of wastewater discharge. There water contacts with chlorine. As chlorine storage facility is dangerous in operation, Technical project envisages use of modern safe ultraviolet disinfection of wastewater. Existing chlorination plant will be deactivated and will be in reserve. Pumping station No. 4 located at the WWTP site discharge treated wastewater into the Don river. Outlet for discharge of treated wastewater into the Don river is dispersive and locates 6.5 km from the WWTP. Flow of wastewater entering the WWTP is measured for Phase I at siphon supplying wastewater to pre-aerators; for Phase II – in Venturi flume; treated wastewater – by flowmeters installed on head conduits at pumping station No. 4. 4.2.4. Wastewater treatment models In the following three different process options are analysed. The chosen options

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are based on the following conditions: A. The current biologic reactors have a sufficient volume to include

the demand biologic nitrogen removal; B. The composition of the wastewater will not allow for both

advanced biologic nitrogen and phosphorus removal, without an addition of additional organic carbon;

C. A chemical precipitation will be needed to achieve the required P-removal level;

D. The separated sludge will be digested, either in new reactors, or in some of the existing ones, after a renovation.

E. The demand for an advanced reduction of nitrogen (denitrification) would most possibly call for a very good availability of organic carbon.

In all options studied below it is foreseen that a part of the separated primary sludge will undergo anaerobic hydrolysis, in order to "liberate" easily degradable organic compounds to enhance the denitrification. First option. The previous studies (elaborated by JACOBS) envisage that the development of the Rostov plant would be reconfigured in accordance with the "A2O" process concept. It should be underlined that this biologic nutrient removal model belongs to a family of similar shaped models, all labelled "single sludge" systems. The "A2O model" is one of the "earliest" technologies in this field. In other words it is not the most up to date variant. Later on very similar systems have occurred within the water industry, such as the BardenNiPho system, the VIP system (sometimes labelled UCT-process). All these systems are to a larger or lesser based on the same concept, with separate reactors for anaerobic, anoxic and aerobic conditions. Second option is based of stage of preliminary sludge formation for fuller phosphorous removal. Then there will be system of preliminary denitrification of activated sludge later referred as “Simple recirculation denitrification”. Third option will be based on a "step-feed" configuration, with a number of anoxic/aerobic reactors in series. In an additional study from JACOBS, presented in June 2004 it is suggested that the VIP process rather than the A2O process would be used as the biologic nutrient removing system. It should be noted that reconstruction of the phase 1 of biological reactors was completed and their technical state was improved. Further improvement of nutrient biological removal will be easily organized. Existing configuration of biological reactors based on traditional configuration of “piston flow” will ensure organization of certain options of “separate sludge”, system of nutrient biological removal. Restructuring of the existing facilities into interrupted operation will require additional investments and activities on the WWTP reconstruction without achievement of high parameters of treatment. SWECO’s analysis shown that pre-precipitation is important even for option with 360,000 m3/day if existing biological aeration tanks will not be enlarged. However, there is a need in additional reactor capacity for anaerobic reaction.

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For anaerobic reactors it is proposed that if sludge stays in methane tanks for 1.5 hours then volume of sludge should be 20,500 m3. Total additional requirements for anaerobic reaction will be about 10,500 m3 for corrected designed load of 360,000 m3/day. For the final design load of 460,000 m3/day the need for additional reactors would be 25,560 m3; for aerobic reactors, the additional volume is assumed to be about 33,760 m3. The total additional need for anaerobic and anoxic reactors would be 59,320 m3 for the revised design load at 460,000 m3/day. Based on this estimates prepared by SWECO it is recommended not to enlarge bioreactor volume but use preliminary sludge formation. Existing volumes can be divided into anoxic and aerobic zones. Some reactors can be equipped both for mixing (denitrification) and aeration (nitrification). Biological removal of phosphorous will be possible in case of anaerobic reactor as proposed in configuration A2/O. Biological removal of phosphorous reduces only soluble phosphorous. Decrease of volume of treated effluents extends only on total amount of phosphorous. Thus, if level of suspended solids in treated effluents will be high then total amount of phosphorous in treated effluents will be high as well. For options with preliminary sludge formation the following is true: used volumes of 62,316 m3 for nitrification and 41,544 m3 for denitrification are sufficient to achieve high level of wastewater treatment from nitrogen compounds. Test on sensitivity to nitrification shown that reactors’ power is sufficient for future loads under normal conditions. The Rostov WWTP would be upgraded to meet more stringent N and P removal standards by use of a pre-precipitation and A/O nitrifying/denitrifying process concept. At present the Rostov WWTP the Phase 1 has a phase of an advanced treatment. The "brush filters" are installed on three out of four lines. As described above the efficiency has a typical "polishing effect. The ability to achieve a major improvement of the effluent quality is very dubious when only the brush filter stage is in use. Nether the less, as an intermediate stage it would be possible to install "Brush filters" in the available volume created in the final settler basins. The available volume would be 10,800 m3, if all sixteen basins were used. As already underlined the need for additional advanced treatment capacity would be needed to improve the discharge quality. By using a final rapid sand filtration stage the water quality would be improved substantially with respect to suspended solids content, and as a consequence also the particulate BOD and phosphorus. The sand filtration stage, once installed into operation would have the following parameters (Table 4.10).

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Table 4.10 Design data for the rapid sand filtration facility at the Rostov WWTP.

Parameter Short term Assumed Design data

"Final" design data

Units

Year 2006 2025

Number of filters in operation 32 32 32

Area per filter unit 93.2 93.2 93.2 m2

Total filter area 2,983 2,983 2,983 m2

Filter type Vertical upflow

Filter media Sand

Design flow 13,833 15,000 20,500 m3/hour

Peak flow 17,677 19,333 27,605 m3/hour

Surface load 4.6 5.0 6.9 m3/hour Maximum surface load 5.9 6.5 9.3 m3/hour

For the stable and successful operation of the sand filtration it is imperative that the filters are backwashed in a regular manner. The initial design of the backwash filter system contains the following parts:

Backwash pumps: 3 units each one of 1,004 m3/h at 20 m w.c., and 110 kW installed power for each one.

Backwash blowers: 2 units each one of 6,000 Nm3/h at 20 m w.c., and 200 kW installed power for each one.

The backwash water will be pumped from the discharge channel downstream the filter plant. The backwash water will be collected in two equalisation tanks each one of 1,200 m3. From these tanks the water would be pumped back into the head of the plant. For this purpose two units of centrifugal pumps would be installed each one of 530 m3/h at 35 m w.c. and 160 kW installed power for each one. The plant is currently operated with a chlorinating stage, in accordance with the SNiP norm. The actual dosage is 3 g/m3 or about 990 kg Cl2/d. The dosage point is downstream the "brush filter" stage in Phase I and for Phase II in the outlet pipe to the main discharge pumping station. For the longer perspective chlorination should be replaced by an alternative disinfecting system. As a long-term replacement Giprokommun has designed an UVplant. The UV lamps will be installed in 9 channels; in each channel there will be 6 sections with 2 modules each, all-together 108 modules sized for 27,600 m3/h of treated wastewater. The discharge channels are equipped with surface aerators for oxygen supply to the treated water. The installation contains in all 7 units of slow speed surface aerators, all with an installed power of 7.5 kW per unit. By using the OCP model for the different operation modes it is possible to compare the efficiency. Tables 4.11-4.17 present load options.

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Table 4.11 Current operation situation, inlet loads, discharge figures and OCP values

Parameter Inlet Discharge Units

BOD5 42,004 6,080 kg/d

Total-N 6,150 1,657 kg/d

NH4-N 789 kg/d

Total-P 1,034 672 kg/d

OCP 263,268 85,633 kg/d

OCP-efficiency 67.5 %

Table 4.12 Short-term load with Stage 1 upgrade, inlet loads, discharge figures and OCP values

Parameter Inlet Discharge Units

BOD5 42,389 1,509 kg/d

Total-N 9,092 1,207 kg/d

NH4-N 150 kg/d

Total-P 1,781 121 kg/d

OCP 384,145 30,484 kg/d

OCP-efficiency %

Table 4.13 Revised 2025 load with Stage 1 upgrade, inlet loads, discharge figures and OCP values

Parameter Inlet Discharge Units

BOD5 70,656 2,293 kg/d

Total-N 12,149 1,310 kg/d

NH4-N kg/d

Total-P 2,409 164 kg/d

OCP 530,238 37,016 kg/d

OCP-efficiency %

Table 4.14 Long-term design load with Stage 1 upgrade, inlet loads, discharge figures and OCP values

Parameter Inlet Discharge Units

BOD5 70,656 3,680 kg/d

Total-N 13,460 1,840 kg/d

NH4-N kg/d

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Total-P 4,416 276 kg/d

OCP 789,673 57,040 kg/d

OCP-efficiency 92.8 %

For the different load situations and with the final technical upgrades installed (including the sand filtration stage) parameters are given in tables 4.15-4.17. Table 4.15 Short-term load with final technical upgrade, inlet loads, discharge figures and OCP values

Parameter Inlet Discharge Units

BOD5 42,389 905 kg/d

Total-N 9,092 905 kg/d

NH4-N 150 kg/d

Total-P 1,781 45 kg/d

OCP 384,145 18,110 kg/d

OCP-efficiency %

Table 4.16 Revised 2025 load with final technical upgrade, inlet loads, discharge figures and OCP values

Parameter Inlet Discharge Units

BOD5 70,656 983 kg/d

Total-N 12,149 983 kg/d

NH4-N kg/d

Total-P 2,409 49 kg/d

OCP 530,238 19,654 kg/d

OCP-efficiency %

Table 4.17 Long-term design load with final technical upgrade, inlet loads, discharge figures and OCP values

Parameter Inlet Discharge Units

BOD5 70,656 1,380 kg/d

Total-N 13,460 1,380 kg/d

NH4-N kg/d

Total-P 4,416 92 kg/d

OCP 789,673 29,900 kg/d

OCP-efficiency 96.2 %

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The upgrade of the plant with respect to nutrient removal will provide a substantial improvement of the discharge quality. The OCP- efficiency will increase from about 67 % to almost 93 %. A further investment in an efficient polishing step would only improve the efficiency by another 3 %. The chosen step-by-step strategy for the upgrade of the plant may be seen as a very well founded decision, in the light of the OCP-analysis. 4.2.5. Planned activities on sludge treatment The sludge treatment would be changed in some major parts as compared with the present operation. The following alterations are foreseen: The mixing of primary sludge and waste activated sludge may be ended, or used as an

alternative option when found suitable. The primary sludge will be stored for a short time in 2 of the existing sludge thickeners (diameter = 18 m). There are toe objectives for this treatment:

A. To provide an efficient thickening of the sludge. B. To establish an anaerobic hydrolysis of the sludge in order to get more easily

degradable fatty acids available for denitrification in the biological stage. Excess water from the thickeners, along with a limited amount of thickened sludge will be pumped into the anoxic chamber.

Activated sludge will be thickened separately. This will be accompanied by use of two gravity thickeners with addition of polymers for enhancement of the thickening process. At a later stage it may be needed to upgrade the sludge thickening by means of mechanical dewatering.

The anaerobic sludge digestion should be changed. The key project objective is to reduce methane emission. Digestion workshop will be designed taking into account:

A. The amount of sludge from the WWTP will be almost the same despite the process applied.

B. Primary sludge and activated sludge will be loaded into methane tanks in series.

C. Methane tanks should be constructed in stages in compliance with stages as described above.

Digestion will be based on termophilic treatment with a typical operation temperature of 55°C.

E. Emitted methane will be used for energy production. Typical calculation of the process will be based on the fact that digestion degree will be about 50% of removed organic matter. Organic matter will be converted into liquid and biogas.

Sludge volume was estimated based on implementation of system for nitrogen and phosphorous removal. The sludge streams at the Rostov WWTP have been calculated for the Phase I (Table 4.18).

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Table 4.18 Sludge production and sludge streams at the Rostov WWTP, Phase I

Sludge flow/design situation Short-term 2025 design Long term Units Primary sludge 33,007 59,668 69,000 kg/dayChemical sludge 6,640 7,200 9,200 kg/dayDry solids content in sludge 3 3 3 %Daily sludge flow to thickening 1,322 2,229 2,607 m3/dayActivated sludge 9,538 10,810 17,140 kg/dayDry solids content in sludge 1 1 1 %Daily sludge flow to thickening 954 1,081 1,714 m3/day

Main options for sludge treatment are given below: 1. The sludge from the primary settlement, a mixture of primary and chemical

sludge will be pumped to the existing small sludge thickeners. This is typical method during the first years of operation. This will be accomplished by a recycling of the waste activated sludge to the pre-aeration tanks and finally removed from the water process along with primary and chemical sludge.

2. Activated sludge will be thickened separately in large thickeners. This operation mode will be needed only at a later stage when sludge production will increase.

As in Table 4.18 sludge amount will be substantially lower under present conditions compared to the designed values. This may allow use of only some of the existing thickeners during the first years of operation. Needs in thickening capacity are analysed in Table 4.19. The existing sludge thickeners, 4 units 18 m diameter ones may be used for thickening of the total amount of mixed sludge for the sludge amounts for a number of years. These thickeners need reconstruction. At a later stage, when sludge amount will increase it can be thickened in two separate sludge streams. All four thickeners will be used for primary and chemical sludge treatment (Table 4.20). At a later stage for activated sludge one large sludge thickeners will be required. Even in conditions of full designed capacity it will be possible to re-circulate part of activated sludge flow to pre-aeration stage. Due to this recirculating ability recirculating flow will not exceed 50% of total activated sludge flow. Amount of sludge after thickening is given in Table 4.21. Thus, existing volume of thickener will ensure facilities operation using classical gravity thickening. Mechanical thickening of sludge will be unnecessary within the entire forecasted period. Even addition of polymer at the phase of gravity thickening will be not required within first years of operation.

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Table 4.19 Analysis of needed sludge thickener capacity at the Rostov WWTP, option 1, designed parameters for all sludge entering gravity thickener

Parameter Short term Revised 2025

Acceptable values

Units 4 4 n.a. nosType Circular

gravityCircular gravity

Circular gravity

SS-load on thickeners 65,688 77,678 < 80 kg/daySpecific SS-load on thickeners 65 76 <80 kg/m2/daySurface per unit 254 254 n.a. m2

Total surface 1,018 1,018 n.a. m2

Water depth 3.5 3.5 >3.0 mVolume per unit 891 891 n.a. m3

Total volume 3,563 3,563 n.a. m3

Diameter 18 18 18 mDry solids in compacted sludge 5.5 5 > 4.5 %Daily sludge flow after thickening 1,194 1,554 n.a. Organic part of the sludge 70 70 n.a. %Organic amount of sludge 45,982 54,375 n.a. kg/day

Table 4.20 Analysis of needed sludge thickener capacity at the Rostov WWTP, option 1, designed parameters for primary and chemical sludge entering one gravity thickener (for a long-term period)

Parameter Long term Acceptable Units Thickeners 4 n.a. nosType Circular gravity Circular gravity SS-load on thickeners 78,200 n.a. kg/daySpecific SS-load on thickeners 77 <80 kg/m2/dayThickener surface 254 n.a. m2

Total surface 1,018 n.a. m2

Water depth 3.5 >3.0 mVolume per unit 891 n.a. m3

Total volume 3,563 n.a. m3

Diameter 18 18 mDry solids in compacted sludge 6 >4.5 %Daily sludge flow after thickening 1,303 n.a. m3/daySludge organic part 70 n.a. %Amount of organic in sludge 54,740 n.a. kg/day

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Table 4.21 Amount of sludge after thickening for three different levels of load

Parameter Short-term Corrected for 2025 Long-term Units Dry solids, total amount 54,483 77,678 95,340 kg/dayDry solids in compacted sludge 5.5 5 5.3 %Daily sludge discharge after thickening 1,194 1,554 1,793 m3/daySludge organic part 70 70 70 %Amount of organic in sludge 45,982 54,375 54,375 kg/day

One of the reconstruction key objectives is to minimize methane emissions from sludge: sludge anaerobic digestion and use of biogas for power generation. A number of factors will determine digestion efficiency, such as dry solids retention time in methane tank, organic load, safety against uncontrolled accumulation of fatty acid and heat control. As stated above the digestion at the Rostov WWTP will occur at T = 55°C. Sludge retention time in a methane tank is determined by minimum time under which bacteria form methane. Theoretically this time is about 5 - 6 days. In addition a safety factor of about 2 - 2.5 is added to theoretical retention time in order to compensate load fluctuations and composition of organic load. Later it should be kept in mind that ratio between theoretical and actual hydraulic retention time is 1:2in a separate reactor. Thus, minimum retention time in each anaerobic methane tank will be 10 -12 days. For a very large plants such as the Rostov WWTP organization of digestion should include at least four separate volumes. These can be arranged as two lines with two methane tanks working in series. It is possible to use all four methane tanks in parallel. The second important criterion is to determine maximum organic load on methane tanks expressed in kg of organic matter per 1 m3 of methane tank per day. Mixed process with maximum organic load (< 4.5 kg/m3/day) is chosen for a high-rate digestion typically operated by means of a continuous feeding. Another practical condition is to define dry solids content in sludge. For energy balance methane tank should be filled with as little water as possible. As total sludge flow has to be heated from 20 - 22°C (as an average annual value) to 55°C it is clear that sludge thickening is very much needed for "energy saving". Maximum "desired" content of dry solids in sludge entering methane tank is determined by other process parameters, such as possibility to pump sludge through the pipe system and heat exchangers, and sludge mixing inside methane tanks. According to practice content of dry solids in undigested sludge should be less than 7%. Sludge thickening based on gravity thickening will result in content of dry solids 5 - 6%. This is positive for good operation of digestion system. Giprokommunvodokanal studied possibility to use existing methane tanks each 4,000 m3 after necessary reconstruction. The following options were addressed:

A. An upgrade of the existing methane tanks by use of stainless steel sheets inside the existing structure and by strengthening of concrete structure. In this

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case the available digestion volume will be 3,500 m3, total 14,000 m3. This volume will be enough to meet SNiP norms for anaerobic digestion but leaving no "extra" volume for fluctuations in load or sludge flow. This volume will be best suitable for "intermediate" design level = 360,000 m3/day.

B. An upgrade of the existing methane tanks in a similar way but with an increase of each methane tank height in order to get methane tank volume of 5,000 m3. This option will fit for the final design level = 460,000 m3/day.

C. Construction of four new methane tanks in concrete. Existing methane tanks will be demolished as available space will be inadequate for construction of new methane tanks. In this case methane tanks are sized for final target level = 460,000 m3/day.

All other structures and equipment for sludge digestion and gas handling will be identical regardless shape of methane tanks. Thus, it is possible to compare three alternative options by marginal construction costs. Based on the existing Russian costs, investment costs for three possible options of methane tanks can be defined as follows: Option 1. Total cost of four reconstructed methane tanks each 3,500 m3 is 30 million roubles. Option 2. Total cost of four reconstructed methane tanks each 5,000 m3 is 40 million roubles. Option 3. Total cost of four new methane tanks each 5,000 m3 is 64 million roubles. Provided that reconstruction of the existing methane tanks is technically reasonable further analysis is focused on whether an extension of the methane tank capacity by 40% (from 14,000 m3 to 20,000 m3) will increase operational costs. Comparison of two options is given with respect to operational costs. Potential for savings is based on the fact that level of digestion is increasing with increase of sludge retention time in methane tanks (Table 4.22). Table 4.22 Relation between dry solids retention time in methane tanks and level of sludge digestion

Dry solids retention time, days Level of digestion, % 5 407 4510 5012 5216 55

Comparison of three design load options with total digestion volume of 14,000 and 20,000 m3, respectively are given in Table 4.23. Increase the methane tanks volume from 3,500 to 5,000 m3 will not lead to increase of operational costs. Annual cost savings will be 2.0 - 3.1 million roubles/year. Costs for sludge transportation are part of these costs. At present Rostov Vodokanal stores dewatered sludge at site. However, soon there will be no place for sludge disposal and new site must be found. This will mean that there will be additional operational costs for sludge transportation and disposal. If sludge transportation and disposal cost 100

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roubles/ton then additional annual savings will be 250,000 - 350,000 roubles/year. In its turn "pay-back period" will be 3-4 years in case of a larger methane tank construction. Based on this SWECO recommends to construct 4 methane tanks with total volume of 20,000 m3, each 5,000 m3. if this will be adopted the methane tank for the Rostov WWTP should have sizing given in Table 4.24. Table 4.23 Comparison of digestion performance under different loads

Parameter Short-term Corrected load for 2025

Long-term Units

Digester size 3,700 5,000 3,700 5,000 3,700 5,000 m3

VSS-reduction 69,279 69,279 80,611 80,611 110099 110099 kg/dayGas production 5.5 5.5 5.2 5.2 6.0 6.0 %Energy potential, total 1,307 1,307 1,550 1550 1830 1830 m3/dayElectric energy output 70 70 70 70 70 70 %Gain in electric production 48,495 48,495 56,427 56,427 78,664 78,664 kg/dayAnnual gain (350 days) 3 3 4 4 4 4 numberGain in operation cost, electricity 3,700 5,000 3,700 5,000 3,700 5,000

m3

Heat energy output 11,100 15,000 14,000 20,000 14,000 20,000 m3

Gain in heat energy output 4.4 3.2 4,0 2,8 5.6 3.9

kg/ m3/day

Reduced amount of sludge 8.54 11.5 9 12.8 7.65 10.9 dayPotential savings in polymer (4 kg/ton DS 47 51 48 52.5 46 51 %Gain in operation costs, polymer 22,793 24,732 27,085 29,624 36,185 40,119 tons/dayTotal gain in operation cost at short term 46,486 44,547 53,526 50,987 73,914 69,980 tons/dayDigester size

1,307 1,307 1,550 1,550 1,830 1,830 m3/dayVSS-reduction 3.6 3.4 3.45 3.3 4.0 3.82 %

Thus, if 11 days are taken as a main criterion then organic load will be kept at a reasonable level in case of “long-term” option. If necessary digestion volume will be organized distributed into two lines, each reactor will have volume of 5,000 m3. In its turn this will allow "stage-by-stage" investment by construction of only three out of four methane tanks. Forth methane tank will be built when it will be necessary. In case of

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"corrected design loads for 2025" methane tanks capacities will be insufficient if only three methane tanks will be working. Thereupon construction of the forth methane tanks will be logical at an early stage. The need for sludge heating will be dominant for internal process, especially in winter. Further utilization of heat in digested sludge by "sludge/sludge" heat exchangers will limit need in sludge heating by hot water in a closed circuit for gas engine cooling. Stage of sludge heating by classic heat exchanger based on "water/sludge" heat exchanger will ensure proper temperature for digestion in methane tanks. In summer need for gas engine cooling will not be arranged only by sludge heating. Excess heat in the water-cooling circuit will be processed separately. Table 4.24 Designed size of methane tank for the Rostov WWTP

Parameter Short term For 2025 Long-term Units Total dry solids amounts 69,279 80,611 110,099 kg/dayDry solids in thickened sludge

5.5 5.2 6.0 %Daily sludge flow from thickening

1,307 1,550 1,830 m3/dayOrganic part of the sludge 70 70 70 %Organic amount of sludge 48,495 56,427 78,664 kg/dayUnits 3 4 4 numberVolume per reactor 5,000 5,000 5,000 m3

Total volume 15,000 20,000 20,000 m3

VSS-load 3.2 2,8 3.9 kg/m3/day

Retention time 11.5 12.8 10.9 dayDigestion degree 51 52.5 51 %VSS-reduction 24,732 29,624 40,119 kg/day SS-amounts after digestion 44,547 50,987 69,980 kg/day Volume at digestion 1,307 1,550 1,830 kg/m3/day

SS-concentration after digestion 3.4 3.3 3.82 %Digestion temperature 55 55 55 ºCDesign temperature for raw sludge 16 16 16 ºCMaximum temperature for raw sludge 28 28 28 ºC

Table 4.25 gives a rough indication of the sludge volumes that may be expected (JACOBS GIBB). Additional volume of sludge generated as a result of phosphorous chemical stripping is given in the Table, as well as volume of generated sludge. The UK experience shows that phosphorous chemical stripping up to 1 mg/l will increase sludge volume by 20%.

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Table 4.25 Estimated sludge volume

Type of Sludge With Chemicals for P Removal

Without Chemicals for P removal

m3/d % DS m3/d % DS Primary sludge 1,220 3.0 1,220 3.0 Waste Activated 4,550 0.7 3,641 0.7 Totals 5,770 1.3 4,861 1.3

Sludge treatment for further utilisation. Proposals on sludge treatment are based on mesophilic digestion. Other options may be considered during implementation phase, including stabilization with lime and composting. In addition to minimization of methane emissions other obvious benefits from the digestion of the sludge are:

In conditions of thermal digestion reduction of pathogens (salmonella and streptococcus) in sludge will be substantial. This will make sludge more suitable for reuse compared to sludge discharged from the WWTP now;

Reduction of sludge by 35% will result in direct reduction of operational costs on polymers (for dewatering) and transportation costs.

As already discussed use of gas energy for electric power support at the WWTP and sometimes for heating of buildings will contribute to reduction of operational costs.

Temporary storage of dewatered but not digested sludge causes odour problems. Complaints from population will likely to increase unless an efficient anaerobic digestion of sludge will be organised.

Digested sludge will be transferred into a temporary storage reservoir before dewatering by the existing centrifuges. Centrifuges are in a good technical condition. However, system of automation does not operate due to absence of supplier instructions. Centrifuges parameters are given in Table 4.26. Table 4.26 Summary of technical parameters of centrifuges at the Rostov WWTP

Parameter Short-term

Corrected for 2025

Long-term Units

Amount of sludge to dewater 44,547 50,987 69,980 kg/dayCapacity per unit Flow 100 100 100 m3/hourDry solids (DS)-capacity 4,000 4,000 4,000 kg/hourDS-capacity as utilised at 12 h/d, 2 centrifuges 1,856 2,124 2,916 kg/hour DS content in dewatered sludge 28 28 28 %Sludge amounts after dewatering 159 182 250 m3/dayAnnual amount of dewatered sludge 58,070 66,465 91,224 m3/yearRequirements in polymers 4 4 4 kg/ton

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Daily use of polymer 178 204 280 kg/dayAnnual use of polymer 65,039 74,441 102,171 kg/year

Higher level of certain pollutants in the reject water from centrifuges must be regarded as a "negative" effect. Key pollutant will be ammonia nitrogen released from sludge due to anaerobic hydrolysis. Typical concentration of NH4-N in reject water is about 10 - 15% of incoming amount of ammonia nitrogen. Final sludge disposal At present there are no clearly formulated proposals on future sludge utilization. Developing proposals on sludge use and disposal it is necessary to consider world experience on their use in reclamation of technogenic excavations (open pits), authorized and non-authorised damps, and other technogenic objects. Chemical phosphorous stripping The cheapest reagent for chemical removal of phosphorous up to 0.6 mg/l is alum - (Al (SO4)3) with cost of 6,000 roubles/ton. Proposed dose at stage of preliminary precipitation will be about 50 g/m3 under normal operation conditions. Daily requirement under different conditions of load is given in Table 4.27. Introduction of chemical pre-precipitation will increase removal of organic matter during primary sedimentation from 30% to 55% expressed in BOD5. This will reduce organic load on biological reactors and will reduce requirements in energy for aeration. Change as compared with the current load will result in savings of oxygen and energy consumption (Table 4.28) – 0.918 rouble/kWh. Table 4.27 Expected consumption levels of alum at the Rostov WWTP under different wastewater discharge

Load case Short term Revised 2025 Long-term Units Precipitation agent Alum Alum Alum Daily flow 330,000 360,000 460,000 m3/dExpected dose 50 50 50 g/m3

Daily use 16,500 18,000 23,000 kg/dayChemical sludge amount 6,600 7,200 9,200 kg/dayAnticipated cost for chemical agent

36,135,000 39,420,000 50,370,000 rouble/year

Specific cost for chemical agent

0.3 0.3 0.3 rouble/ m3

Table 4.28 Changes in oxygen and energy consumption needs in biological reactors

Short term Revised 2025 Load Without precipitation

With precipitation

Without precipitation

With precipitation

Units

Organic load into reactors

29,672 19,075 49,459 31,795 kg BOD5/day

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Oxygen supply, AOR 36,664 29,564 56,229 44,394 kg/dayOxygen supply, SOTE 83,737 67,521 128,423 101,393 kg/dayEnergy needs 1,108 893 1,700 1,341 kWh/hourDaily use of energy 26,592 21,432 40,800 32,184 KWh/dayAnnual energy consumption

9,706,080 7,822,680 14,892,000 11,747,160 KWh/day

Anticipated cost for aeration energy

8,910,181 7,181,220 13,670,856 10,783,893 roble/year

Specific cost for aeration energy

0.07 0.06 0.10 0.08 rouble/ m3

Annual savings by pre- precipitation

1,728,961 2,886,963 rouble/year

In case of anaerobic digestion amount of sludge will decrease by about 35%. In its turn this will reduce need in polymers for dewatering. At present there are no expenditures on sludge transportation as dewatered sludge is stored at site. However, final sludge disposal place has to be identified, thus, reducing transportation costs. Immediate benefit for the Rostov WWTP due to introduction of anaerobic digestion will be longer sludge storage at the WWTP site, as well as decrease of the required volume for annual storage from 35,000 to 30,000 m3/year. Another side effect of anaerobic digestion introduction and energy recovery will be savings in electric energy, as biogas will be used for power generation. Adding up additional expenditures for pre-precipitation and savings due to digestion introduction provides information for calculation of net additional operational costs for reconstructed Rostov WWTP. In short term conditions additional cost will be about 10.7 million roubles/year or 0.09 roubles/m3 of treated wastewater. In conditions of revised load (year 2025) additional cost will be about 8.3 million roubles/year or 0.06 roubles/m3 of treated wastewater. Total annual savings are given in Table 4.28a. Table 4.28a Annual reduction of operational costs at the Rostov WWTP after reconstruction (roubles/year)

Load case Short term Revised 2025 Potential cost savings by polymer reduction 13,393,020 13,522,560

Annual savings by pre-precipitation 1,728,961 2,886,963Annual savings by digestion gas utilisation 10,322,109 14,726,937Total cost savings 25,444,090 31,136,460

4.2.6 Upgrade of technical design of 2000 and step-by-step division of construction The 2000study presents full reconstruction of the Rostov WWTP. Additional upgrade actions are considered in this section. Reconstruction of the WWTP is designed step-by-step due to lack of funding.

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Water treatment facilities Total capacity for pre-treatment facilities is envisaged as 460,000 m3/day and is divided by 50% for two Phases. Anticipated peak flow for each line is 13,300 m3/hour. Facilities for pre-treatment contain following standard elements: Screening station

At present two parallel screening stations are in operation. These are automatic screens, including solid waste screening, such as automatic transportation and waste pressing. 5 inclined curved 16 mm screens are installed at Phases I and II. The spacing of the screens is 16 mm. These facilities have been recently installed at both phases, and there is no need in their reconstruction. We think that plan given in technical outline to install 3 mm fine grade screens (often named as "step-screens") is justified. Use of fine grade screens has become a "standard procedure" for the modern WWTPs in many countries. Each Phase will need five screens working in parallel. Each screen will have hydraulic capacity of about 4,000 m3/hour and total capacity of 40,000 m3/hour. Intermediate stage will be 360,000 m3/day. Accordingly limited number of new screens (3 at each Phase) will be installed at the first stage. This will ensure good operation in most cases in the nearest future and during “project intermediate stage”. The screening capacity will be as given in table 4.29. Modern presses are equipped with waste washing compartment in order to minimize odours from waste. System of waste washing will wash out organic matter from waste returning them on main treatment facilities. The remaining waste will be easier to dewater and also less smelly. At least two presses for waste will be required at each Phase. Each waste press with capacity 5 m3/hour will locate in the screens building. Dewatered waste will be discharged into containers each 10 m3. Table 4.29 Design data for mechanical screens of the Phase I, Rostov WWTP

Parameter Short-term Corrected designed data

Unit

Average amount of effluents per day 330,000 360,000 m3/dayAverage amount of effluents per hour 13,750 15,000 m3/hourPeak capacity 424,246 464,000 m3/dayDesigned flow per hour, tentative 13,833 15,000 m3/hour

Peak capacity, pre-treatment, tentative 17,677 19,333 m3/hour

Number of screens 2*3 2*3 numberCapacity of one unit 4,000 4,000 m3/hour

Total capacity, 5-8 units operating 20,000 32,000 m3/hour

Free intervals (grate gaps) 3 3 mmTentative amount of waste 6,000 – 8,000 8,000 – 10,000 kg/dayContent of dry matter in some wastes 10 10 %Amount of waste for pressing 60 - 80 80 – 100 m3/dayContent of dry matter after pressing 35 - 40 35 - 40 %Amount of waste after pressing 15 - 24 20 – 30 m3/day

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Sand and grit chambers

The WWTP two phases have different sand removing systems. At Phase I system contains four settlement tanks without supply of compressed air. Only settlement speed of particles controls removal of sand and other abrasives. According to data presented by Vodokanal specialists sand separation efficiency is adequate. Grit traps of the Phase II have the same size as Phase I grit traps and are equipped with aeration system. Pre-precipitation, pre-aeration and primary settling stage Two new stations for reception, storage and handling of alum will be constructed; one plant serving each line. Alum will be delivered by tracks; alum will be unloaded into storage containers; storage time can be up to 30 days storage time. A new building will be built for the preparation of chemical for precipitation. Reactors will be installed in the building for preparation of 10% alum solution for dosing. Four reactors will be built, each 102 m3. For storage of solution another 4 tanks will be constructed, each 205 m3. Dosage pumps will be run proportional to the flow entering the plant, and with time based arrangement as well, to meet the lower need during night-time. Alum liquid will be added downstream grit traps, thus, using the pre-aeration chambers for mixing and flocculation The pre-aeration chambers will be used as at present time, as well as will be able to receive recirculating activated sludge on water treatment line. New aeration pumping station will be installed at pre-aeration reservoirs of Phase II. Existing sludge scrapers at primary sedimentation tanks of Phase II will be replaced with new one; concrete structures will be repaired; sludge pumps will be replaced with stainless steel pumps. Main biologic reactor stage First main biologic reactors of the Phase II will be upgraded in accordance with the following statements: 1. All four lines of Phase II will have similar configuration. However, due to limited funding reconstruction can be divided into two stages. The first stage as intermediate will cover three out of four lines. 2. First part of each reactor will be used as anoxic reactor. Its volume will be 5,200 m3. This reactor will be equipped with submerged slow speed mixers to maintain adequate homogeneous activated sludge liquor in reactor, and also to enhance good mixing of incoming wastewater with microorganisms. Installed number of mixers per reactor will be 6 units per line each of about 4.5 kW. Second half of the existing biological reactors will be used for aerobic reaction. In each line available volume for aeration is 7,770 m3. New bottom aeration devices will be installed at three parallel lines. It is preferable to use rubber membrane discs. Required long-term capacity for the aeration will be 17,730 kg O2/day for each line equal to about 750 kg O2/hour. Actual water depth is about 4.5 m. Required airflow will

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be about 3,050 Nm3/hourh. For recirculation of activated sludge inside biological reactors low pressure high capacity low-pressure pumps submerged into water will be installed: recirculation flows from outlet part of the aerobic reactors to the inlet of anoxic reactors will be 2,000 m3/hour *0.5 m w.c. For process control of the biologic reactors the following on-line probes would be installed: A. At each line a suspended solids meter, range 200 to 8,000 mg SS/l; B. At each aerobic reactor two oxygen meter probes will be installed. Measurement range will be 0.0-10.0 mg O2/l. Final clarifier stage. Phase II secondary settlement tanks urgently need renovation and technical improvement. Important repair works has to be carried on concrete constructions, and discharge channels should be reinstalled. New metal constructions are mainly made of stainless steel. Three out of four lines will be needed at the intermediate stage. These will be refitted with lamella packages, as described above. In total 16 basins will be reconstructed, thus, providing a capacity compliant to a designed flow of 460,000 m3/day for the entire plant. However, it is possible that reconstruction will be divided into stages due to limited investment capacity. Installation of lamella modules in 12 out of 16 basins will meet intermediate capacity of 360,000 m3/day. In each of the existing secondary settlement tanks lamella packages will be installed. All of them will be use half of the reservoir length. Bottom scrapers will be installed and sludge will be transported to the existing sludge drying beds. For return activated sludge flow new dry mounted centrifugal pumps will be installed. Advanced treatment, "brush filters" The existing "brush filter" at Phase I provides better effluents treatment. Both Vodokanal and Giprokommunvodokanal have anticipated that Phase II should have the same phase of advanced treatment. As soon as lamella settlers will be installed at Phase II there will be available space to install "brush filters". Advanced treatment, quick sand filtration Although parts of the construction for sand filters already exist, this stage unlikely to be included in the first stage of reconstruction. Sand filtration stage will be important for meeting SNiP norms. Disinfections stage Existing chlorination station will not change significantly during first stage of reconstruction works. An installation of the UV-radiation plant will become efficient only if sand filtration will be installed. Sludge thickening Sludge thickeners will be renovated and equipped with new sludge scrapers and new

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overflow weirs from stainless steel. For the first stage four thickeners (18 m in diameter) will be renovated. At least one thickener will be operating also as anaerobic hydrolysis reactor. Adequate pumping and piping system will be organized as well. Later the two larger thickeners each 35 m in diameter will be upgraded or replaced with new mechanical thickening devices. Sludge digestion Existing methane tanks will serve only as structural support for new methane tanks from stainless steel sheets installed inside the existing methane tanks. Building containing sludge pumps, heat exchangers, gas collection system, gas engines for power generation and safety devices will be reconstructed, too. Power distribution devices will be properly organised inside the building. Two gas storage tanks will be built each 3,000 m3. A new storage tank for digested sludge will be built with volume of about 2,000 m3. Sludge dewatering Sludge dewatering was installed few years ago. Centrifuges (altogether three units) are operated manually. It will be necessary to ensure operation of automatic system for sludge dewatering. Only with well operating automated mechanisms it will be possible to operate sludge dewatering system in a most cost-effective way 24 hours a day. This will reduce polymer use and will ensure intervals for centrifuges cleaning. 4.2.7. Alternative options to achieve stated objective of the proposed activity The following three were selected for environmental impact assessment:

Zero option: the existing situation will remain at the WWTP, no reconstruction works.

Option with biological treatment, advanced wastewater treatment and chemical removal of phosphorous.

Option with reduction of nutrients using only biological treatment of wastewater.

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Chapter 5. Description of possible environmental impacts for alternatives options Description and assessment of possible environmental impacts for alternative options is done step-by step as options for wastewater treatment and sludge processing are studied. The following are considered as possible sources of environmental impacts:

New constructions to be located at the WWTP site; Elements of the main and supporting technologies (reduction of nutrient

discharges, sludge utilisation, methane utilisation, etc.) which operation is a reason for environmental changes;

Units with life cycle linked with future facilities construction or operation; Units operated earlier but not in use now (drying beds, sludge storage lagoons,

etc.). Types of environmental impact are defined based on two classification features: input in environment and abstraction from environment. Impact parameters are defined based on the following indexes:

type of impact (direct, indirect, cumulative, synergetic, including manifestation in due course);

impact intensity (value in unit time); level of impact (value on unit of volume or are); impact duration; time dynamics of impact; spatial coverage of impact (spread area).

The concept for improving of wastewater treatment with removal of nitrogen and phosphorous is based on renovation and expansion of existing assets, consistent with the stated aim of minimising capital and operating costs. New construction or reconstruction of the following facilities is envisaged at the WWWTP: Phase I works: 1. screen building (reconstruction with installation of "thin" screenings); 2. grit traps will be site for addition of liquid alum (reagent for phosphate compounds

settling), thus, pre-aeration chambers will be used for preliminary sedimentation; 3. aeration tanks (reconstruction with identification of anoxic zone – denitrificator

and aeration zone - nitrificator). Phase II works: 1. screen building (reconstruction); 2. pre-aeration tanks - primary settlement tanks (reconstruction: existing sludge

scrapers will be replaced by new scrapers; concrete constructions will be repaired; sludge pumps will be replaced by stainless steel pumps);

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3. aeration tanks (reconstruction with identification of anoxic zone denitrification and aeration zone - nitrificator);

4. secondary horizontal settlement tanks (three lines out of four will be completed with lamella modules and brush filters - bioreactors with immobilized microflora well proven on Phase 1);

Facilities for wastewater advanced treatment (II stage) of Phases I and II 1. Reception (inlet) chamber (reconstruction). 2. Entry chamber (designed). 3. Filters for advanced treatment (reconstruction). 4. Pumping station for advanced treatment filters (reconstruction). 5. Reservoir for washing water (reconstruction). 6. Filters media storage facility (reconstruction). 7. Aerator trough (aeration tank) (reconstruction, designed). Facilities for sludge processing, Phases I and II 1. Gravel bunkers (extension); 2. Sludge thickeners D=18 m (reconstruction); 3. Methane tanks (re-equipping up to 5,000 m3); 4. Two reservoirs will be constructed for gas storage 3,000 m3 each and new

reservoir for digested sludge storage (capacity 2,000 m3); power generation plant; building for heat exchangers; gas-holders; methane tanks pumping station;

5. Site for mixing wastewater with humin-mineral concentrate, and storage facility;

Supporting buildings and facilities 1. Blowing house and pumping stations No. 1 and 2, pumping station in passes of

capacity blocks of Phase II, pumping station of sludge thickeners (reconstruction), in-site communications will be reconstructed;

2. Reagent storage building with storage facility (two new plants will be constructed for alum reception, storage and processing, one plant will serve line 1 or 2 phases).

Various environmental impacts will be registered both during reconstruction or construction phases due to emission of pollutants, effluent discharges into water bodies, formation and disposal of production and consumption wastes, and other impacts. The following three alternative options were selected for environmental impact assessment:

Zero option: the existing situation will remain at the WWTP, no reconstruction works.

Option with biological treatment, advanced wastewater treatment and chemical removal of phosphorous.

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Option with reduction of nutrients using only biological treatment of wastewater.

5.1. Environmental Impacts at Present The WWTP operation poses certain environmental impacts, in particular:

air emissions; discharge of insufficiently treated wastewater into the Don River; ground water pollution due to infiltration of sludge water from sludge storage

lagoons; waste disposal.

Key technological processes with air emissions are: effluents treatment, preparation of chloric water, burning of gaseous fuel in a boiler-house, gas-welding and electrical welding operations, sharpening works, transport. At present level of wastewater treatment is insufficient and does not meet existing requirements. River water is polluted by nutrients and organic matter due to discharge of large volumes of insufficiently treated wastewater into the Don River. Sediments have significant impact on aquatic ecology. Reconstruction of the WWTP is planned to improve level of wastewater treatment. Sludge disposed in sludge storage lagoons is enriched with organic matter, nutrients, and heavy metals. In case of sludge drying and storage these substances infiltrate in ground water and pollute them. Activities on sludge processing and methane utilisation are planned to dewater and reduce sludge amount. WWTP have no significant impact on topography and geology; hydrology; terrestrial ecology; land use, industry and agriculture; energy consumption; transport infrastructure; cultural heritage. Key environmental impacts existing at present time are presented in Table 5.1. 5.2 Environmental Impacts during Construction There will be no significant impact during construction on climate; hydrology; terrestrial or aquatic ecology; water resources, supply and sanitation; public health (apart from occupational health, discussed below); land use, industry and agriculture; fisheries; energy consumption; transport infrastructure; tourism and recreation; cultural heritage; groundwater quality; or sediment quality. The construction of new buildings and tanks will have a slight impact on topography, but this is not considered to be significant in the context of an industrial complex. All construction work will have a slight positive impact on ‘population, employment and income’ through employment generation. The majority of the potential construction impacts can be minimised through adherence to proper site practice and health and safety procedures. There are a number of Russian norms (standards) for construction practices, including SNiPs and the Manual on Labour and Construction Safety. Potentially dangerous excavations should be fenced off and warning signs erected. The site is not accessible to the general public.

48

Construction works may have minor negative impacts on surface water and air quality through operation of cars, machinery (atmospheric emissions, spillage of petroleum products, etc.). Impacts can be mitigated by correct choice of fuel and proper machinery operation, use of spill control procedures, enhanced control on polluted soil collection and utilisation. The construction of buildings, tanks and underground pipelines may have an impact on the groundwater regime. This impact may be assumed to be negative (in disruption of existing groundwater flows) but the level of impact is likely to be marginal and no mitigation measures would be required. However borehole monitoring should be instituted where there is likely to be groundwater diversion or rising water tables There may be a slight decrease in effluent quality during works which require direct interruption of process lines, but this is likely to be insignificant because retention time would not decrease significantly as the works currently has excess capacity. All works generate construction waste. It is understood that soils excavated during building and tank construction will be used on site. Apart from soils, it is envisaged that the waste generated will be relatively small and therefore have only a slight impact on waste disposal. This impact should be mitigated by compliance with existing requirements (RF and Rostov Oblast ordinances) for collection, temporary storage and final disposal of construction waste. Special activities for waste recycling should be developed and implemented where possible. Components 1 and 2 The construction works comprise removal of existing screens and grit removers equipment and installation of new equipment. This will have a minor negative impact on waste disposal. It is recommended that ferrous equipment should be recycled wherever possible. Во время строительных работ будут удалены существующие решетки и оборудование по удалению крупных частиц, и будет установлено новое оборудование. Образование дополнительного количества отходов потребует новых площадок для их размещения. Component 3 The improvements concern redesign of the secondary aeration tanks and the provision of additional aeration capacity. The construction works include minor changes to the layout of partition walls and the installation of several mixers at different depths. Separate works are required for the excavation and construction of an additional aeration tank, together with feed and return sludge lines and the installation of aeration devices on the tank floor. The excavation works are significant involving the removal of up to 20,000 m3 of soil. The spoil will be used for construction of the tank support walls, site feeder roads and other embankments such that offsite disposal is avoided. Soil will not be disposed outside the WWTP. Component 4 The provision of lamella separators requires only minor construction works to attach the separators which are provided as packaged units. There will therefore be no significant environmental impacts during construction.

49

Component 5 Chemical Phosphorus removal No specific environmental impacts during construction are envisaged as the reagent storage building already exists and is likely to require only minor refurbishment, depending on the choice of chemical and equipment required for its preparation. Component 6 Sludge digestion This component involves extensive construction works which are likely to generate large quantities of waste construction materials. This will be mitigated by compliance with city ordinances on solid waste disposal. Component 7 Sludge dewatering Construction of the centrifuges and associated works is almost complete and was funded by the CSIP, so the impacts are not considered here. Component 8 CHP – Methane use This component will involve the construction of a new building to house the CHP plant. No specific negative impacts other than those discussed earlier are envisaged. 5.3 Environmental Impacts during Operation There will be no impacts during operation on topography, geology and soils; hydrology; water resources, supply and sanitation; and cultural heritage. At this stage, it is envisaged that there will be no significant impact on ‘population, employment and income’ as there will be no major changes in staff needs. Given that this project is grant-funded, it is considered unlikely that it will have a negative impact on the population in terms of ability to pay for services. In a long-term period there are no impacts on land use, industry, agriculture, but some positive impacts can originate due to disposal of less amount of biologically less activated sludge. The new buildings, pipelines and tank are likely to have a minor impact on hydrogeology due to flow diversion. Components 1 - 4 As each of these components form part of an integrated process, they have been assessed as a single process unit. The quantity of grit disposed will not change as a result of the project, but the quantity of screenings will increase with more regular raking and the use of finer screens. There will therefore be a slight negative impact related to increased solid waste disposal and its transportation from WWTW to landfill site. Such impacts probably do not warrant mitigation measures but if desired, these could include installation of a screening press, installation of a macerator and return of screenings to works or installation of a screenings incinerator. Given that the majority of nitrogen in the river appears to be present as ammonium which is detrimental to fish, there may be a minor positive impact on fisheries. Given the complexity of the factors affecting both nitrogen levels and fisheries, however, it is difficult to estimate this impact with any certainty. The reduction of nitrogen levels with the reduction in phosphorus levels is likely to decrease the eutrophication of the river, thus having a minor positive impact on aquatic ecology; and tourism and recreation. These impacts, and the impact of phosphorus reduction are discussed in more detail in

50

the following section. Whilst the amount of sludge produced after the WWTP reconstruction will increase this does not have a corresponding impact on solid waste disposal as all sludge produced from components 1-4 will pass through a closed cycle to the sludge digesters. There is therefore no direct connection between the process improvements and solid waste disposal. Sludge from primary sedimentation is expected to contain some disease pathogens as well as parasitic eggs and cysts. Reducing the quantity of sludge carried over into the final effluent through replacing the scraper mechanism in the primary tanks…With less carryover of sludge into the final effluent there is also expected to be a small positive impact on public health. Whilst the new screening process will require less manpower to operate dosing of ferric sulphate or lime, reagent monitoring and control will require increased manpower. The new system could therefore be operated with no net change in manpower. There is also unlikely to be any significant change in pumping duties once the new system is operating hence no change in energy requirements. It is envisaged that there will be no significant operational impacts on climate; energy consumption; transport infrastructure; terrestrial ecology; groundwater quality; sediment quality or air quality. Component 5 Chemical P removal Total phosphorus has the potential to greatly affect the growth rate of individual algae at concentrations up to 200-300 μg/l and probably beyond. Under normal circumstances, increases in riverine concentrations from likely background concentrations to such levels are therefore potentially extremely important to the ecology of the river. Phosphorus is present in wastewater in three forms: orthophosphate, polyphosphates and organic phosphorus compounds. During biological treatment three main changes occur:

Organic materials are decomposed and their phosphorus content is converted to orthophosphate;

Inorganic phosphates are utilized in forming biological flocs; and Most polyphosphates are converted to orthophosphates.

After biological treatment, phosphorus is largely present as bioavailable orthophosphate, an ionic compound that reacts and precipitates out of solution in the presence of metal salts. Given the presence of phosphates in the sediments and the equilibrium balance of phosphorus, the following impacts are predicted. During the first year a steady decline in the levels of concentration of dissolved nitrogen and phosphorus will be recorded in water of the Don river directly downstream of Rostov-on-Don. An obvious decline in the Don river nutrient status downstream would be seen no sooner than 3 years after the reconstruction. Reduced levels of eutrophication and hence reduced algal blooms will have a positive impact on river water quality by reducing the frequency of low oxygen and toxin release events. This will have a beneficial impact on aquatic ecology; public health, fisheries; tourism and recreation. Given the large phosphorus reservoir in the riverine sediments,

51

positive impacts on sediment quality will accrue over time. In the short term, therefore, there will be no positive impact on sediment quality. The use of chemical reagents for phosphorus stripping has both advantages and disadvantages as shown in Table 5.4. Chemical dosing will cause an increase in sludge volume. The actual increase depends both on reagent chosen and the level of phosphorus in the wastewater (i.e. the dosing level). This represents a minor impact on groundwater quality due to the possible disposal of larger quantities of sludge to the lagoon. The chemical stripping process should be monitored carefully to ensure optimum reagent dosing. Given the present state of options, it is envisaged that this component will have no significant impact on climate; terrestrial ecology; energy consumption; groundwater quality and air quality.

52

Table 5.1. Environmental impacts of the WWTP at present time

Environmental impact

Natural environment Human environment Environmental Quality

Technological process and WWTP functional zones

Topo

grap

hy

, geo

logy

&

Clim

ate

Hyd

rolo

gy

Hyd

roge

olo

Terre

stria

l E

colo

gy

Aqu

atic

E

colo

gy

Pub

lic H

ealth

Land

use

, in

dust

ry&

Fish

erie

s

Ene

rgy

cons

umpt

ion

Tran

spor

t in

frast

ruct

ure

Tour

ism

&

recr

eatio

n

Cul

tura

l he

ritag

e

Sur

face

wat

er

qual

ity

Gro

undw

ater

qu

ality

Sedi

men

t qu

ality

Air

qual

ity

Soi

ls q

ualit

y

Solid

was

te

disp

osal

Wastewater treatment (grates, grit traps, first stage reservoirs, primary settlement tanks, aeration tanks, secondary settlement tanks, bioreactors)

0 0 0 0 0 - - - - 0 - 0 0 - 0 - - 0 - - 0 -

Sludge processing (sludge thickeners, centrifuges, reservoirs for sludge digestion)

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 -

Sludge disposal (drying beds)

- 0 0 - - 0 0 - 0 0 0 - 0 - - 0 - - -

Key: ++ Major positive impact; + Minor positive impact; 0 No significant impact;

- Minor negative impact; -- Major negative impact

53

Table 5.2. Environmental Impacts during Construction

Environmental impact

Natural environment Human environment Environmental Quality

Component

Topo

grap

hy,

geol

ogy

& s

oils

Clim

ate

Hyd

rolo

gy

Hyd

roge

olog

y

Terr

estri

al E

colo

gy

Aqu

atic

Eco

logy

Pub

lic H

ealth

Land

use

, ind

ustry

&

agric

ultu

re

Fish

erie

s

Ene

rgy

cons

umpt

ion

Tran

spor

t inf

rast

ruct

ure

Tour

ism

& re

crea

tion

Cul

tura

l her

itage

Sur

face

wat

er q

ualit

y

Gro

undw

ater

qua

lity

Sed

imen

t qua

lity

Air

qual

ity

Soi

ls q

ualit

y

Solid

was

te d

ispo

sal

1. Screening, grit removal 2. Primary settlement tanks 3. Secondary aeration tanks - 4. Lamella settlers 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5. Chemical P stripping 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 6. Sludge digestion 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 - - 7. Sludge dewatering 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 8. CHP – methane use 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Key: ++ Major positive impact; + Minor positive impact; 0 No significant impact; - Minor negative impact; -- Major negative impact

54

Table 5.3. Environmental Impacts during Operation (during the next 5 years)

Environmental impact

Natural environment Human environment Environmental Quality

Technological process and WWTP functional zones

Topo

grap

hy, g

eolo

gy &

so

ils

Clim

ate

Hyd

rolo

gy

Hyd

roge

olog

y

Terr

estri

al E

colo

gy

Aqu

atic

Eco

logy

Pub

lic H

ealth

Land

use

, ind

ustry

&

agric

ultu

re

Fish

erie

s

Ene

rgy

cons

umpt

ion

Tran

spor

t inf

rast

ruct

ure

Tour

ism

& re

crea

tion

Cul

tura

l her

itage

Sur

face

wat

er q

ualit

y

Gro

undw

ater

qua

lity

Sed

imen

t qua

lity

Air

qual

ity

Soi

ls q

ualit

y

Solid

was

te d

ispo

sal

Effluent treatment (grates, grit traps, settlement tanks, aeration tanks, bioreactors)

0 0 0 0 0 ++ + + + 0 0 + 0 + + + + 0 +

Chemical P stripping 0 0 0 0 0 + + + 0 0 0 + 0 + + + 0 0 -

Sludge processing (sludge thickeners, centrifuges, methane tanks)

0 + 0 0 0 0 + + 0 0 0 0 0 0 + 0 + 0 +

Sludge disposal (drying beds) + 0 0 + + 0 0 + 0 0 0 0 0 + ++ 0 + + ++

CHP – methane use 0 + 0 0 0 0 0 0 0 0 0 0 0 0 0 0 + 0 0

Key: ++ Major positive impact; + Minor positive impact; 0 No significant impact; - Minor negative impact; -- Major negative impact

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Table 5.4. Advantages and disadvantages of chemical P stripping

Advantages Disadvantages

Reliable, well-documented technique Chemical costs can be reduced substantially if waste pickle liquors (ferrous chloride or ferrous sulphate are available and can be used Controls are simple and straightforward - easy to maintain high P removal efficiency by controlling metal salt dosing rate. Relatively easy and inexpensive to install at existing facilities Sludge can be processed in the same manner as in non-P-removal systems Primary clarifier metal addition can reduce organic load to secondary unit by 25-35%.

Chemical costs higher than for biological systems. Significantly more sludge produced than wastewater treatment process without metal addition; may overload existing sludge handling equipment; higher sludge treatment and disposal costs. Sludge does not dewater as well or as easily as conventional STW sludges where metal salts are not added. Requires tertiary filtration to remove P in suspended solids. Coloured effluents if iron salts are used.

Component 6 Sludge digestion Sludge digestion will eventually ensure major environmental improvements as the process leads to a significant reduction in sludge volume, and allows for the capture of methane for beneficial use. Digestion converts the volatile organic fraction of the sludge into a mixture of methane and carbon dioxide. The organic load could be reduced by as much as 50%, depending on the efficiency of the digesters. In the absence of specific designs, it is therefore only possible to assess the likely impacts in general terms. Reduction of sludge volume is likely to have a positive impact on groundwater quality and air quality as it will decrease the volume of sludge disposed to the lagoon in the short term. This is discussed further in the sludge dewatering section. The lower volume will also have a positive impact on energy consumption by reducing energy required at the sludge dewatering stage. During the digestion process the elevated temperature and long residence time in anaerobic conditions results in the destruction of pathogens thus reducing the potential health risks from the sludge. This represents a minor improvement to public health. The capture of methane in the digesters therefore represents a significant climatic improvement due to reduce of methane emissions. The digesters will require an additional heating circuit based on natural gas, as the CHP system will supply on average only 2/3 of the heat required to raise and maintain digester temperatures. This represents a potentially negative impact on energy consumption and climate (due to release of CO2) which may be mitigated by making use of the CHP cooling water to preheat digester feed when heat in excess of that needed for building heating is available. The operation of digesters represents a potential risk due to the presence of areas

56

where explosive gas/air mixtures can be present. It will therefore be vital to introduce the concept of "zoning". Areas where explosive mixtures may be present should be identified, and special precautions taken within these areas. This will include locating equipment which may cause sparks outside the danger zone, and careful choice of mechanical and electrical plant, pipelines etc. within the zone. Operation of digesters is a complex process, and staff will need to be given full training and ‘hands on’ experience. This is vital to the efficient operation of the digestion process. It is therefore envisaged that this component will have no significant impacts on aquatic ecology; terrestrial ecology; transport infrastructure; tourism and recreation surface water quality; or sediment quality. Component 7 Sludge dewatering The centrifuges are designed to produce a handleable sludge cake of approximately 35% dry matter. In the near future sludge from the WWTW will primarily be disposed of in the existing lagoon and drying beds at the site. The lagoon currently represents an unknown pollution risk. Risk from leaching to groundwater is not identified. The reduction in sludge arisings as a result of digestion will therefore lower the risk of pollution of the Don. This risk will reduce further if and when use of the lagoon ceases and the existing sludge are removed. The lagoon is an uncontrolled biological system and emits gases and volatile organic compounds which although not toxic in the concentrations produced may be a source of odour nuisance at some distance outside the site boundary. The reduction in volume and BOD content of the sludge passed to the lagoon will therefore have a minor positive impact on air quality and human use of the area. The drying and subsequent aerobic storage of the sludge leads to a further reduction in infectious organisms particularly of helminths. The sludge drying process may therefore has a small positive impact on public health. With continuing sludge disposal to the lagoon, it is envisaged that there will be no significant impact on terrestrial ecology; land use, industry and agriculture; transport infrastructure; solid waste disposal; tourism and recreation; or sediment quality. Component 8 CHP – methane use The net result of the CHP is the conversion of methane to carbon dioxide. Carbon dioxide has a lower negative impact on climate through global warming than methane. Calculations suggest that a reduction in methane emissions by 70% and in CO2 equivalent emissions by 60% can be expected. Electricity and heat generated will be used on site, thus significantly reducing use of electricity generated by the coal fired power plant at Novocherkassk. Renovated WWTP will need a significantly higher energy input than the existing situation mainly due to the high energy demand of the digesters and dewatering facilities. This energy would be obtained from the Novocherkassk power station but the construction of the CHP system is therefore considered to be likely to reduce fossil fuel consumption at the Novocherkassk power station. This will further reduce CO2 emissions, as well as reducing emissions of sulphates and particulates and production of coal ash. General environmental impact assessment for the activity on the WWTP reconstruction is given in Table 5.5 in compliance with the WB requirements.

impactDirect Impacts

Disturbance of stream channels, aquatic plant and animal habitat, and spawning and nursery areas during construction

0 No impact

Alterations in watershed hydrologic balance when wastewater is exported by collection in large upstream areas and discharged downstream

0 No significant change to volume of water discharged to river

Degradation of neighbourhoods or receiving water quality from sewer overflows, treatment works bypasses, or treatment process failure

0 No significant change to sensitivity of biological treatment process. Duplication of digesters and treatment lines should preclude minor process failures.

High probability of permanent improvement

In the short term (<5 years) upgrading of the WWTW will result in a localised reduction of nutrient and organic loading to the Don. Phosphorus levels however may not significantly decrease in the short term due to re-equilibration of bound P in the sediment.

Degradation of receiving water quality despite normal system operation

Low probability of temporary minor adverse impact

Minor risk from pollution of receiving water by overdosing of phosphorus stripping reagent. Recommendations made for installation and operation of monitoring system to minimise risk of overdosing

Public health hazards in the vicinity of discharges or reuse sites during normal operation of system

High probability of minor permanent improvement

No deterioration of water quality near the outfall is expected. Pathogen and odour levels in sludge disposed to lagoon will progressively diminish as the improvements to treatment lines, digester operation and centrifuges are implemented.

Contamination of land application sites: soils and crops by toxic substances and pathogens; groundwater by toxic substances and nitrogen

0 No plans in the short term to apply sludge to land

Failure to achieve desired beneficial uses of receiving waters despite normal system operation

High probability of major permanent improvement

Will play a major role (along with other pollution reduction initiatives) in the longer term towards achieving MACs for fisheries downstream of Rostov and drinking water within the Azov region (see Section 5.5.1)

Odours and noise from treatment process or sludge disposal operations

0 Works is sited in an established industrial area. Sludge will be less malodorous as a result of the improved process

Potential negative impact

Impact Comments and recommendations

Emissions of volatile organic compounds from treatment process

High probability of permanent minor improvement

Digestion of sludge will result in lower emissions of volatile organic compounds

Soil, crop or groundwater contamination and disease vector breeding or feeding at sludge storage

High probability of minor improvement in the short-term and major improvement in the long-term

Sludge disposed to lagoon will contain lower concentrations of N, P and organic matter, thus polluting groundwater less than current sludge.

Heavy metal concentration in the sludge will also be increased during the digestion process thereby reducing the potential to leach into the groundwater after disposal.

Improvement of sludge quality as progressive implementation of WWTW investment programme and subsequent removal of sludge from current storage lagoon (for co-disposal with daily sludge arisings at landfill) would lead in time to remediation of the lagoon site

Worker accidents during construction and operation, especially in deep trenching operations

Low probability of temporary and avoidable and adverse impact

Impact mitigated by complying with established norms and procedures.

Serious public and worker health hazard from chlorine accidents

0 This project does not involve works on chlorination facilities

Nuisances and public health hazard from sewer overflows and backups

0 Duplication of digesters and treatment lines together with excess capacity should preclude minor process failures.

Failure to achieve public health improvement in serviced area

0 No public health improvement within Rostov city. In the long term, may improve public health aspects of downstream recreation.

Dislocation of residents by plant siting

0 No impact

Perceived or actual nuisances and adverse aesthetic impacts in neighbourhood of treatment works

0 No impact as works located in an established industrial zone

Accidental destruction of archaeological sites during excavation

0 All works on existing footprint, with no archaeological sites

Potential negative impact

Impact Comments and recommendations

Indirect Impacts

Unplanned development induced or facilitated by infrastructure

0 No impact

Regional solid waste management problems exacerbated by sludge

No change in impact in near term. Long term major permanent improvement

Sludge is currently stored on site. A long term sludge disposal strategy will be developed as part of the RVK Strategy Plan. Minor amounts of construction waste (mostly inert) for disposal to existing landfill.

Loss of fisheries productivity High probability of medium improvement in the long term

Likely improvements to fishery productivity only in the longer term since effective propagation depends not only on surface water quality but on longer term improvements to sediment quality and ecological restoration

Decrease of tourist and recreation activities

High probability of minor permanent improvement

Expected minor improvement at Azov Sea resorts and Rostov city with respect to bacteriological/viral quality as a result of upgrading of WWTW.

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Chapter 6 Relevant Environmental Legislation for Selected Options According to the existing Russian Federation legislation any activity with environmental impact has to be regulated by legal-regulatory documents of federal, regional and local level. Main Federal Laws regulating environment protection, natural resource conservation and recovery are listed below.

• On Environmental Protection; №7, January 10th, 2002.

• On Environmental Expertise, №174, November 23rd, 1995.

• On Fauna, №24, April 24th, 1995.

• On Wastes №89-FL, June 26th, 1998.

• On Atmospheric Air Protection, №96, May 4th, 1999.

• On Specially Protected Natural territories, №33, March 14th, 1995.

• On Hydraulic Structures Safety, №117, July 21st, 1997.

• On Safe Use of Pesticides and Agrochemicals, №109, July 19th, 1997. The following laws containing environmental requirements were adopted in the Rostov Oblast:

• Oblast law “On payment for water bodies use”, No. 230, March 28th, 2002.

• Oblast law “On administrative offence”, No. 273, October 25th, 2002.

• Oblast law “On municipal administrative commissions in the Rostov Oblast”, No. 274, October 25th, 2002.

• Oblast law “On use of The Earth's interior in the Rostov Oblast”, No. 275, October 25th, 2002.

• Oblast law “On forests in the Rostov Oblast”, No. 3, September 23rd, 1994. The following documents regulate methodological basis of environmental design in the RF:

• "Adoption of the "Instruction on environmental justification of economy or other activity". RF Ministry for Natural Resources, №539, December 29th, 1995

• Regulations on assessment of planned activity impact on environment in the Russian Federation (approved by RF Goskomecologiya No. 377, May 16th, 2000; registered in the RF Ministry of Justice on June 4th, 2000, No. 2307).

• Section 8 “Engineering and technical surveys” in SNiP 11-02-96 developed by the RF Ministry of Construction (Russia Minstroy), 1997;

• Section “Engineering and technical surveys for construction” in a “Register of rules of engineering surveys for construction” (SP-11-102-97) developed by the RF State Committee on housing and building policy (Gosstroy of Russia);

• Sanitary norms and rules for design of industrial Enterprises (SP 245-71);

• Sanitary norms and rules for design, construction and operation of MSW landfill;

• Sanitary rules of keeping of populated territories (SanPiN 42-128-4960-88);

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• Sanitary rules and norms on protection of surface water from pollution (SanPiN № 4630-88);

• Sanitary rules on protection of air quality in the populated places (the USSR Ministry of Health, 1989);

List of key legal documents used in engineering and technical surveys includes: SNiP 10-01-94. System of legal documents in construction. General terms. SNiP 11-02-96. “Engineering survey for construction. General terms. GOST 17.0.0.01-76. System of standards in the sphere of environmental protection and improvement of natural recourse use. GOST 17.0.0.02-79. Measurement assurance of air, surface water and soil pollution control. GOST 17.1.1.03-86. Nature protection. Hydrosphere. Classification of water use. GOST 17.1.1.04-80. Nature protection. Hydrosphere. Classification of ground water in terms of water use purposes. GOST 17.1.2.04-77. Nature protection. Hydrosphere. Parameters of state and rules for taxation of fisheries water bodies. GOST 17.1.3.04-82. Nature protection. Hydrosphere. General requirements to protection of surface and ground water from pollution by pesticides. GOST 17.1.3.05-82. Nature protection. Hydrosphere. General requirements to protection of surface and ground water from pollution by oil and oil products. GOST 17.1.3.06-82. Nature protection. Hydrosphere. General requirements to ground water protection. GOST 17.1.3.07-82. Nature protection. Hydrosphere. Rules for control of water bodies and watercourses quality. GOST 17.1.3.11-84. Nature protection. Hydrosphere. General requirements to protection of surface and ground water from pollution by mineral fertilizers. GOST 17.1.3.13-86. Nature protection. Hydrosphere. General requirements to protection of surface water from pollution. GOST 17.1.4.01-80. General requirements to methods of oil products identification in ambient and wastewater. GOST 17.1.5.02-80. Nature protection. Hydrosphere. Hygienic requirements to recreation zones of water bodies. GOST 17.1.5.03-81. Nature protection. Hydrosphere. Analyzers of total organic carbon in ambient water. GOST 17.1.5.04-81. Nature protection. Hydrosphere. Instruments and devices for sampling, primary handling and storage of ambient water samples. General technical requirements. GOST 17.1.5.05-85. Nature protection. Hydrosphere. General requirements to sampling of surface and marine water, ice and precipitation. GOST 17.2.1.03-84. Nature protection. Atmosphere. Definitions of pollution control.

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GOST 17.2.3.01-86. Nature protection. Atmosphere. Rules for control of air quality in settlements. GOST 17.2.4.02-81. Nature protection. Atmosphere. General requirements to pollutants identification methods. GOST 17.4.1.02-83. Nature protection. Soils. Classification of chemical substances for the purpose of pollution control. GOST 17.4,1.03-84. Nature protection. Soils. Definitions of chemical pollution. GOST 17.4.2.01-81. Nature protection. Soils. Nomenclature of sanitary state parameters. GOST 17.4.2.03-86. Soils passport. GOST 17.4.3.01-83. Nature protection. Soils. General requirements to soils sampling. GOST 17.4.3.03-85. Nature protection. Soils. General requirements to methods of pollutants identification. GOST 17.4.3.04-85. Nature protection. Soils. General requirements to control and protection from pollution. GOST 17.4.3.06-86. Nature protection. Soils. General requirements to soil classification in terms of chemical pollutants impact. GOST 17.4.4.02-84. Nature protection. Soils. Sampling methods and methods of samples preparation for chemical, bacteriological, helminthologic analysis. GOST 17.4.4.03-86. Nature protection. Soils. Identification method of potential erosion danger due to rainfalls. GOST 2761-84. Sources of a centralised household and drinking water supply. Hygienic, technical requirements and selection rules. GOST 2874-82. Drinking water. Hygienic requirements, quality control. GOST 4979-49. Water for household, drinking and industrial water supply. Methods of chemical analysis. Sampling, samples storage and transportation. GOST 20444-85. Noise. Transport flows. Methods for measurement of noise characteristic. GOST 23337-78. Noise. Methods for noise measurements on residential area and in living and public buildings. GOST 24481-80. Drinking water. Sampling. GOST 28168-89. Soil. Soil sampling. GOST 12.1.003-83. SSBT. Noise. General safety requirements. SanPiN 2.1.4.027-95. Zones of sanitary protection and water supply sources, as well as drinking water distribution systems. SanPiN 2.1.4.544-96. Water quality requirements for a decentralised water supply. Sanitary protection of sources. SanPiN 4630-88. Sanitary rules and norms for protection of surface water from pollution. SanPiN 4631-88. Sanitary rules and norms for protection of coastal zones water from pollution at water use sites.

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SanPiN 42-128-4433-87. Sanitary norms of permissible concentrations of chemical substances in soil. СН № 3077-84. Sanitary norms for permissible noise in living and public buildings All of the above-mentioned federal and oblast laws, legal-regulatory documents will be applied both during design stage and reconstruction/operation stages.

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Chapter 7. Description of Environmental Conditions 7.1 Natural conditions within the WWTP site

The Rostov WWTP works (Phases I and II) is located on the left bank of the River Don, within a floodplain, 3 km downstream railway bridge, opposite the Besymyanny Island, 100 m off the coastal line (see Figure 7.1). Construction site of the Rostov port borders the WWTP site at north together with the Don River; WWTP Phase III construction site - from the south-east; pond of a fishing farm and Zarechnaya industrial zone - from the northeast; pond of a fishing farm, bituminous concrete plant and motorway Rostov-Bataysk - from the west and northwest. 7.1.1. Climate Area has a moderate continental climate with dry, unsteady moistening. Steppe plains are lowlands with soft rolling relief sloping towards the Azov Sea. This part of the Rostov Oblast is accessible for the Black sea air masses. In the Rostov Oblast annual amount of total radiation is 111-113 kcal/cm2, annual radiation balance is positive (47-48 kcal/cm2) and increases from December and January to June – July. Largest increase is from February to March (almost 5 times) and decrease from October to November (5-17 times). Specifics of geographic location determine absolute domination of continental moderate air. Territory receives 11% of Arctic air masses, 68% of moderate air masses and 21% - tropical. In Rostov dominating are winds with eastern component (53%), of which eastern winds are 31%; winds with western component amount to 35%, of which western winds are 17% (Figure 7.2). Strong winds (more than 15 m/sec) have special practical interest. Their average recurrence in Rostov-on-Don is 28 days/year, maximum – 54 days. Largest number of days with strong wind (up to 44) is recorded in winter and lowest (up to 22) – in summer. The prevailing winds are easterly. Load on the works increases under strong winds. In Rostov within a year it changes from 20 kg/m2 in August, September to 58 kg/m2. In Rostov average annual air temperature is 8.9oC. The coldest period lasts for 42 days from 5th January to 15th February, warmest period lasts 76 days (June – August). In winter daily temperature variation is poor due to high recurrence of cloudy weather. In Rostov average temperature amplitude does not increase 2.2-3.4°C and in summer it increases up to 10.3°C due to large number of clear days. The average annual precipitation is 604 mm (GMO Rostov). The majority of precipitation occurs in a form of rains (70% for Rostov). Snow (16%) dominates among other forms of solid precipitation (30%). Total duration of rains is 793 hours/year. On average snow cover appears at the beginning of December (data of the GMO Rostov). There are 25 days with snow cover. Thickness of the snow cover is 5-8 cm; but steady snow cover forms not very winter. 7.1.2. Topography and hydrography In terms of geomorphological zoning scheme of the Volgo-Don region this area belongs to the Don River valley (Figure 7.3). The Don River modern valley developed on buried alluvial and marine formations of

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mainly regressive cycles starting from Baku time, and located on the Lower Sarmat loams with residues of the Upper Eopleistocene (Margarotovo) and Baku (Semibalka) terraces. The Upper Eopleistocene lacustrine and eluvial Scythian loams form foundation of the modern left bank of the Don River. Width of the Don modern alluvial floodplain terrace varies from 8 to 18 km. Height is 2-5 m. Surface is cut by flood water into shallow gullies (eriks and former river-beds). Some places are waterlogged. Terraces substrate is marine loams, sands, loamy sands and loamy soils. Dams of fishing farms locate along the entire Don floodplain. Their length is 60-80 m, width – 3-5 m at top and 10-15 m at the bottom. Their height in the upper reach is 1-2 m and in the lower – 5-7 m. they are composed by loamy soils. Railway and motorways embankments locate in the Don river floodplain between Rostov and Bataysk. They are 6-7 km long, 40-50 m wide and 8-10 m high. They are composed by sand and crushed stone. Despite larger precipitation in summer its impact on surface flow is minor due to soils aridity in summer and high evaporation. Melting snow water is the main source for surface water. Spring high water period starts at the second half of February and maximum levels are recorded at the end of March – beginning of April. Water level rises by 4-6 m. Recession of flood starts mid-May. High water period lasts 1.5-2 months. The highest recorded level was in 1917 with level rise up to 597 cm above regular water level. In summer low water period starts with rare floods. Minimum water level is August-September. Duration of low water period is 200-250 days. In October its slowly starts to rise by 0.3-0.5 m. Winter low water period starts the first decade of December. It lasts for 60-70 or 120-130 days. At the end of December – beginning of January, after freezing of the river water level decreases up to minimum. But winter low levels are higher than summer low levels. Stable freezing occurs only in severe winters and persists for 70-80 days. Ice thickness is 0.2-0.3 m, ice drift lasts 16 days. The Don River is a typical plain river and navigable through the whole length. River width is 190-712 m, depth – 5.7 – 11.0 m, flow velocity is 0.1 m/s. Bottom is loamy and sludgy, sandy here and there. Right bank is high (50-80 m), steep (up to 15°); left bank is low and gentle. Average riverbed slope is 2.2%. In the lower reaches the Don River divides into branches and canals. Snowmelt is the main source for the Don River (amount up to 68%), ground water is 28% and rainfalls – only 4%. Construction of the Tsimlyansk reservoir changed water regime. Now it is mainly defined by releases from by-wash. High water period is low and extended. Flow volume higher than 3 km3 is observed only in coincidence of releases from reservoir and flood wave from the Seversky Donets River. After regulation value of annual flow decreased by 28% and its further reduction is expected. Flow seasonal distribution has changed. Spring flow reduced by two times from 21.8 to 9.6 km3. In other seasons flow increased by almost twice, e.g. in summer-autumn from 3.9 to 7.9 km3 and in winter from 2.2 to 3.3 km3. Compared to natural regime water temperature reduced in spring and increased in autumn. Tides arising due to winds pose a significant impact at the river mouth. Easterly wind drives water away and lows water level (by 2.5 m in 1910). South-easter wind flows from a sea, surge marine water and rises water level. Average annual water discharge for

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1952-1982 was 694 m3/s and it was changing from 406 to 1140 m3/s. In winter low water period water mineralization near Rostov is 0.43 g/l, in summer-autumn – 0.71 g/l. in terms of chemical composition the Don river water is hydrocarbonate-sulphate-chloride, hydrocarbonate- chloride – sulphate and calcium-sodium-magnesium. Ponds are part of the hydrographic network. Ponds are fed mainly by atmospheric precipitation and partly due to ground water in a form of springs. Water mineralization depends on precipitation and seasonal air temperature fluctuations. Fishing ponds locate in the relief lowering (eriks, marshes). As a rule they are bordered to prevent flooding. Fishing ponds are filled with water for fish growing period (April-October). These are typical technogenic landscapes. At present they are rarely used for fish growing and mainly populated by meadow-marsh communities. 7.1.3. Hydrogeology and protection of ground water Water-bearing Mid-pleistocene, i.e. modern sub-horizon presents Quaternary aquifer in the Don river valley. On the left bank of the Don river deposits are presented by sands, loamy clays, rarely by loamy sand. Thickness of water-bearing deposits is 12 m. depth of ground water changes from 0.2 – 14 m increasing towards floodplain terraces. Water class is sulphate magnesium-calcium, calcium-sodium-magnesium, rarely chloride-sulphate-sodium. Aquifer is fed by inflow of ground water from undercover loamy sands and by infiltration of surface water and precipitation. Aquifers discharge into the Don River and partly into fractured limestone. In terms of geomorphology the Rostov WWTP site locates on the left bank of the Don river. Here during construction of the WWTP a layer of sand was filled on a surface up to absolute heights of 5.0-6.0 m (fine-grained sands, rarely mean particle size). The following are lying below: the upper quaternary and modern alluvial deposits presented by loamy sands (with humus in the upper part – 0.6-0.8 m) underlay by black and dark grey clay, with peat, silt and rare layers of dust-borne sand. Below clay is greenish-grey or dark-grey with sands and layers of dust-borne sand. Sands (fine-grained and rarely mean particle size, water saturated) are uncovered under clays at depth of 10.0-12.0 m. Total thickness of sands remained uncovered. In terms of hydrogeology this area is a mixture of modern technogenic and upper quaternary alluvial deposits with ground water. Depth of the studied area is 20 m. Water-bearing rocks are presented by inwash sands, alluvial loamy and sandy deposits hydraulically interconnected in a single water-bearing thickness formed due to natural feed and infiltration of technogenic water at the WWTP site. The Don river water drains ground water. 7.1.4. Vegetation cover Vegetation cover is mosaic and presented by several types of vegetation (Figure 7.4). Marsh vegetation is class of European-Siberian grass and grass-Hypnum marshes. Large-grass, large-sedge and halophilous scirpus marshes are found in this area. Large-grass marsh-fluxes locate in wide lowering, low coasts of eriks. They are formed by Phragmites australis, Scirpus lacustris, S. tabernaemontanii, Typha angustifolia, T. laxmannii, T. australis. Reed and reed mace associations are less popular than reed-beds. Marsh motley grass is not abundant and consists of the mentioned above species. Meadow vegetation includes four types of most typical meadows: excess moistening,

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medium moistening – non-salt and salt, insufficient moistening – salt. Near-water and aquatic vegetation locates in floodplain canals and eriks, as well as in artificial water bodies (ponds, canals). Vegetation of near-water coenosis belongs to the same formations as marsh vegetation (reed, reed mace and mainly reed-beds formations). Flood-plain forests locate in the mouth floodplain and on islands. Fragments of flood-plain ribbon pussy-willow forests and black poplar forests are very rare and often exist as separate standing trees. Small areas of shrubby osiers present forest vegetation. Poplar forests locate between the WWTP and harbor walls. Anthropogenic modifications of vegetation are due to pastures, mowing, destruction of vegetation cover under construction works and building activities, and ploughing up. Modern state of vegetation cover can be assessed as stable. 7.1.5. Soils Soil map is given on Figure 7.5. Alluvium, mainly clay is a soil forming rock of meadow soils in the Don river floodplain. Ground water locates 1.0-2.5 m from surface but sometimes even higher. Alluvium-meadow soils locate on river mouth and eriks lowering. Soils have well-developed stratification due to heterogeneous granulometric composition and presence of submerged humus horizons. Average thickness of humus layer is 30 cm. Humus content in a layer A is 3-5%. These soils have good water and physical qualities and can be used for growth of vegetables and horticultural crops. Meadow sombric soils form in conditions of periodic excessive moistening. Thickness of humous-accumulative horizon varies from 20 to 40 cm. Transitional humus layer B has thickness 20-60 cm depending on specific conditions. Humus content in a layer A is 4.5 – 7.5%. Environment reaction is close to neutral (6.3 – 7.5). Meadow-black earth soils locate in higher plain sites. They are close to black earths of plain-steppe zones. Genetic horizons are clear; transitions are gradual. On average thickness of humus horizon is about 95 cm, varying from 60 to 110 cm. Ground water lies deeper than 3 m. Humus content in upper horizons is 6.5. Environment reaction is close to neutral or alkalescent: ph varies from 6.7 to 7.8. Ooze-marsh and deltaic soils develop on flooded sites under pileup due to the westerly winds. Ground water level is close to a surface. In summer evaporating geochemical barrier is active. Thus, salts content is high in soils upper horizons. Salination and desalination processes influence on soils physical-chemical features. Humus content is high (up to 6-8%). However, in this soils gleying processes are well developed, oxygen regime is unfavourable for meadow vegetation. Thus, grass marshes communities dominate on ooze-marsh soils. 7.1.6. Fauna Four classes of terrestrial vertebrates inhabit the Don floodplain:

I. Amphibia - Amphibia; II. Reptilia – Reptile; III. Aves - Birds; IV. Mammalia – Mammals.

Amphibia

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The following inhabit described area: smooth newt (Caudata order); red-spotted fire-bellied toad, toad frogs, green toad, frogs (Ecaudata order). Smooth newt and frog are listed in the Red Book of the Rostov Oblast with status “category I”. They require rehabilitation and protection of environmental niche. Reptile Two orders represent Reptiles. These are:

Chelonia order - pond tortoises; Squamate order (9 species)

Suborder Lizards – sand lizard, Eremias. Suborder Serpent – grass snake, water snake, smooth snake, Renard’s viper,

Columber jugularis, C. ravergieri and C. najadum. Snakes population drastically reduced due to heavy anthropogenic pressure (decrease of non-arable lands, pollution with different chemicals, high recreational load) and killing of snakes. Columbers are listed in the Red Book of the Rostov Oblast: C. jugularis (status “catergory II”), C. ravergieri and C. najadum (status “catergory I”). Renard’s viper is included into the Red Book of the Rostov Oblast with status “category II”. Birds Birds are widely presented in the Don river valley – up to 90 species (without Passerine).

Rare and endangered bird species Accipiter badius and short-toed eagle (status category I); black stork, harmel, white-tailed eagle, golden eagle (status category II); osprey (status category III) were listed in the Red Book of Russia. Pale harrier and stock-dove (status category I); white stork, common crane, honey buzzard, oystercatcher and black-tailed godwit (status category II); ruddy sheldrake, booted eagle, corncrake and eagle owl (status category III) were listed in the Red Book of the Rostov Oblast. All these species are recommended for the Red Book of Russia. Seven of 19 nesting species (harmel, Accipiter badius, white-tailed eagle, corncrake, black-tailed godwit and pratincole) are elements of the Rostov Oblast gene pool. White-tailed eagle is a monument of wild nature with an esthetic interest. Mammals The followings species are found in the area:

European hedgehog. Cheiroptera – 4 species of Nyctalus family. Duplicidentata sub-order – European hare. Muridae (about 10 species in the studied area) – spotted souslik, great jerboa,

southern birch mouse, harvest mouse, house mouse, Norway rat, musk-rat, common vole, Russian mole rat.

Carnivora – corsac, fox, raccoon-dog, polecat, weasel, stone marten. Perissodactyle - wild boar.

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7.1.7. Specially protected areas Specially protected areas are areas of land, water surface and air with ecosystems and object having special environmental, scientific, cultural, aesthetic, recreation and sanitary importance and fully or partly withdrawn from use by special; decrees. They have a special regime of protection. The following categories of the above-mentioned areas are defined:

State natural reserves, including biosphere; National parks; Natural parks; State natural game-reserves; Natural heritage; Dendrology parks and botanic gardens; Medical-sanitary districts and resorts.

In the Don area there are 2 wetlands and 3 major ornithological territories with international rank, 1 reserve, Don federal reserve fishing area, 7 federal hunting game-reserves, 26 Oblast game-reserves and more than 130 local monuments of nature. State game-reserves are effective form of environment protection. They exist for many years and their network is gradually expanding. In the Rostov Oblast by 1982 there were 1 Republican and 21 Oblast game-reserves. Manych-Gudilo republican game-reserve mainly covers Kalmykiya territory and protects unique bird colonies. Its area within the Orlovsky and Remontnensky districts (Rostov Oblast) was 150,000 hectares. After Rostovsky reserve was established (total area 9,464.8 hectares) part of the game-reserve area became part of the reserve. Large area of lands lost their status of specially protected areas. At present in the Rostov Obalst there are 26 state hunting game-reserves of Oblast importance with the total area of 458,500 hectares (4.5% of Oblast area) and 14 majory ornithological territories. Different cultural and historic values are found in the area as it has been populated for a long time. Stone tools, household goods were excavated downstream Rostov during archeological digs at ancient sites. Scythians appeared in the Don area in the 8th century, the Iron Age. Burial mounds are most typical for the Scythian period. At the end of the 4th century Sarmat tribes (kindred to Scythians) penetrated to the Don area from the east. Numerous monuments of the Sarmat culture can be found in Rostov, Khapry, settlement Gnilovsky, etc. First Greek settlements originated in the Don area in the 6th century. The largest was Tanais fortress, main trading center of Bosphorous kingdom. Monuments of the Upper palaeolith are found in the Don river delta (sites Kamennaya Balka 1, 2, 3, Mokry Chaltyr). There are no specially protected areas, natural monuments, architecture and historically important building in the construction zone. 7.2. Social and economic situation

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7.2.1. Demography The area locates in the southwest of the Rostov Oblast and was populated for ages. Before the 20th century the majority of population was involved in agriculture, but closer to the beginning of the 20th century metallurgy, metal-working, trade and transport started to develop. Decrease of population (gradual in after-war time and drastic in the 1990-s) resulted in migration increase. Having reached maximum in 1995 population gradually decreases. Decrease of population in cities started in 1991 and in the rural areas since 1998. Rostov Oblast is currently following the national trend of decreasing population. According to the All-Russia population census (2002): Rostov population is 1070.2 thousand inhabitants, Azov – 82.2 thousand inhabitants, Taganrog – 282.5 thousand inhabitants. Parameters of population reproduction significantly changed in post-war period. Compared to pre-war period birth rate decreased by 4 times and death-rate being minimal in 1960-s has increased almost up to the pre-war level. Since 2000 birth rate is increasing. In 1999 number of new-born children was 6,783 persons and by 2002 it was 8,401. This is typical for other towns of the studied area. In 2002 the mortality in Rostov was 15,023 persons, in Azov – 1236 and in Taganrog – 4847. However, mortality dominates birthrate. Major towns locate in the area adjacent to the project site. Industry and agriculture, including irrigated are developed in this area. The area has the highest population density both rural (more than 20/km2) and average population density (more than 100/km2). 7.2.2. Population economic activity The area belongs to Rostov industrial node including Rostov-on-Don, Taganrog, Novocherkassk, Azov, Aksai and Bataysk. All enterprises are closely linked with each other. Machine-building is the priority branch in this largest industrial node. Plants produce grain combines, steam-boilers, aircrafts and helicopters, instruments and apparatuses, cars, press-forging equipment, vessels, etc. The major joint-stock companies are Rostselmash, Beriev’s TANTK, Rosvertol, Tagaz, Krasny Kotelschik, Santarm, GPZ-10, Azovsky KPA Plant, Donpressmach, NPP KP Kvant, Priboi, etc. Food industry holds the second place in terms of production volume. The key branches are: meat production (meat-packing plant Rostovsky, Bekon, Tavr); dairy industry (dairy Rostovsky, Taganrogsky, Azovsky); butter-making industry (Yug-Rusi, Rabochii, etc.); tobacco industry (Donskoy tabak); wine industry (Rostov factory of champagne); alcoholic beverage industry (Rostov vodka, etc.); brewing trade (Baltika-Don, etc.), flour-and-cereals industry, macaroni industry, baking, fish industry, etc. The following large enterprises form chemical complex of the Rostov industrial node: Empils, Emkras. Plants of Azov, Rostov-on-Don and Taganrog produce plastics, polymeric materials, and medical products. Woodworking and pulp and paper industries produce furniture, paper, wallpaper, wood chipboards (plants Rostovbumaga, Tamek, Rostovmebel, Rostovtara, Azov packaging plant, etc.). Light industry consists of leather-shoe industry (Donobuva, Rostovobuv, Taganrog tannery, Donskaya leather, shoe factories of Azov, Bataysk and tagnrog), clothing

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industry (Elegant, Clothing factories № 1, № 3, № 5, Azov clothing factory), knitting and hosiery industry, etc. Metallurgical and construction complex is important in production. Taganrog metallurgical plant “Tagmet” produces 80% of branch production in the region (steel, steel pipes). Construction plants produce construction bricks, fabricated reinforced concrete structures, etc. Thousands of people are working in industry. All enterprises locate close to reliably operating sewage and water supply systems. 7.3 Assessment of the current environment situation Environmental and geochemical surveys in the WWTP area helped to assess modern state of environment and to forecast possible environment changes under anthropogenic impact. Survey objective was to find environmental parameters for the period before the proposed project start. 7.3.1 Survey methodology Analysis of the modern state of environment included: collection and analysis of published and summarized materials, field surveys, office studies of data collected. The following data and materials were used to assess environment state in the area of the WWTP:

• Actual data on environment protection and map material provided by Rostov Vodokanal.

• Data of specially authorized state agencies in the sphere of environmental protection and natural resources use:

Committee on Environment Protection and Natural Resources under Rostov Oblast Administration;

Central Administrative Board on Natural Resources for the Rostov Oblast, RF Ministry for Natural Resources;

Rostov Oblast Center for hydrometeorology and environment monitoring; Rostov Oblast Centre for State Sanitary and Epidemiological Supervision.

• Published data. Field survey included:

• clarification of gepmorphological, engineering and geological, hydrogeological and landscape conditions defining environmental impact of the object;

• identification of possible sources of soils, bottoms, surface and ground water pollution based on modern situation analysis and area use in the past;

• identification of possible migration routes and possible sites of pollutants concentration.

During surveys schemes with location of potential pollution sources were prepared. Specialists of the scientific enterprise “Environmental laboratory” cross-examined local population about retrospective use of the area, about emergencies happened in the past, about cases of mass death of plants, animals and birds. They searched for visual signs of landscapes pollution.

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Vegetation map, soils and landscape maps were prepared based in survey results. Relative background for soil cover was defined during engineering and environmental surveys in the studied area. Geochemical materials received during geochemical studies at the area of list L-37-X (“Greater Rostov”) in 1995-2000 and environmental-geochemical observations in 2001-2002 formed a reference point for further monitoring observations. The upper soil horizon (0.0-0.2 m) with maximum intensity of geochemical processes was tested during lithochemical studies. Soils were sampled on geochemical profiles located in a way to test main landscapes in the studied area. The Don River and floodplain lakes, as well as ground water were sampled during hydrochemical studies. Samples were preserved using standard methodologies and were sent to the regional laboratory centre of Uzgeologiya. Geo-ecological maps of pollutants distribution in different landscape components were developed using GIS ArcView GIS 3.2 and Spatial Analist 1.0 module. 7.3.2. Surface water assessment Main impact of the existing and proposed activity is on the Don River. Detailed assessment of surface water quality is given below in terms of hydrochemical, hydrobiological and sanitary-toxicological parameters. The Lower Don hydrochemical, hydrobiological and sanitary-toxicological regime forms as a result of many factors. The Tsimlyansk reservoir forms main features of river chemical composition. The Lower Don water is a water with inherited chemical composition. Initial chemical composition of the Don river water significantly transforms moving downstream. This is mainly due to inflow of substance of natural and anthropogenic origin. Part of substances enters channel as a result of lateral erosion. Other substances enters water column from bottom sediments and ground water. Follow-up evolution of water chemical composition is due to redistribution of components in the rivers. Discharge of insufficiently treated and polluted water of industrial enterprises, housing and communal services, washing of fertilizers, residues of pesticides, organic matter, heavy metals from farming lands and farms, storm water, mining and drainage water pose impact on the Don river water quality. 7.3.2.1 Hydrochemical assessment of surface water

This section is based on results of generalized hydrochemical and hydrobiological information presented in the “Year-books of surface water quality” on hydrochemical and hydrobiological parameters within the area of the North-Caucasus Hydromet for a long-term period. In terms of chemical composition the Don river water in all phases of hydrological cycle belongs to a hydrocarbonate class, sodium group. Water mineralization varies from 0.3 to 1.4 mg/l. It slightly reduces during high water period and increases during summer-autumn and winter low water period (near Aksai it is 460-890 mg/l). values of mineralization and main ions are given in Table 7.1.

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Table 7.1 Main ions and the Don river water mineralization, mg/l (average annual) Site Са2+ Мg2+ НСО- SO4

-2 Cl- ∑ ions

settlement Razdorskaya 76 26.5 208 171 143 755

Rostov-on-Don 84.0 37.0 194 197 141 759

Azov 79.8 38.6 190 195 160 774

Oxygen regime of the river main channel is satisfactory. Decreased content of oxygen (below 6 mg/l) were often recorded in delta watercourses, especially in the ranch Mertvy Donets, Prevoloka and Peschany. This is due to weak water mixing in conditions of temperature increase. The Lower Don is polluted by oil products, copper ions, and phenols in the course from the Tsimlyansk reservoir dam to the river mouth. Most polluted areas locate near Volgodonsk, Semikarakorsk, Aksai, Rostov. Near Rostov concentration of oil products is up to 2 mg/dm3, phenols - 0.012 mg/dm3, copper – 6 mg/dm3. Sometimes in the Lower Don concentration of phenols and oil products was up to 30 and more MAC, nitrates and nitrites – up to 15-34 MAC, copper ions – 15 MAC, zinc – 4 MAC. Water pollution level in the Lower Don increases towards the river mouth. Untreated and insufficiently treated residential, industrial, mining and drainage water, as well as water discharged by irrigation systems are the main sources of the Lower Don water pollution. Intensive navigation and diffuse run-off from arable lands contributes into water quality. The Lower Don tributaries (Seversky Donets, Aksai, Temernik, Manych) contribute to its pollution. For the last decades concentration of nitrogen and phosphorous increased in water bodies of the Lower Don together with increase of primary production and fluctuation of dissolved oxygen concentration. As a result, intensity of self-purification processes decreased. Average annual mineralization of the Don river water increased from 464 to 717 mg/dm3. Thus, in some areas technogenic component of ionic flow achieved or increased natural value. Flow of suspended solids is 3 times less. Now silts dominate at places of sand deposits. At some places concentration of pollutants in water, silts and vegetation increased by 3-25 times. Data on average annual concentrations of pollutants for the last decade were used for assessment of the Don river water quality. Tables 7.2 – 7.3 present results for the Don reach between “input” (upstream Aksai) and “output” (near settlement Koluzaevo). Change in average annual concentrations is given in figures 7.6-7.7. In the 1990-s the Don river water quality improved in terms of oil products, copper, iron and nitrates (I the lower reaches). This is likely due to decline in industrial and agricultural production recorded in the Don basin in 1990-s. relative improvement of water quality in the lower reaches appeared later than in the upper reaches. In winter water quality deteriorates both in the Don River and its tributaries.

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Table 7.2 Average annual concentrations of pollutants in the Don River upstream Aksai (mg/dm3)

Years Parameters 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999

Suspended solids 47 32 36 72 75 154 96 82 - -

Dissolved oxygen 9.78 11.5 10.58 11.07 11.21 10.45 10.92 9.90 - -

Magnesium 47 38 45 39 31 53 45 32 - -

Chlorides 194 116 222 167 114 155 1.51 156 - -

Sulphates 243 178 242 180 120 209 245 275 - -

Mineralization 948 646 971 765 552 792 875 1011 976 878

COD 83 62 61 64 52 19 60 34 - -

BOD5 3.91 3.41 3.56 3.66 3.48 3.18 2.36 3.25 2.96 3.65

Ammonia nitrogen

0.033 0.005 0.010 0.24 0.21 0.30 0.16 0.29 0.31 0.47

Nitrite nitrogen 0.063 0.114 0.014 0.026 0.025 0.042 0.023 0.026 0.018 0.026

Nitrate nitrogen 0.055 0.098 0.199 0.33 0.40 0.18 0.14 0.19 0.23 0.50

Phosphates (Р) 0.099 0.129 0.109 0.078 0.12 0.113 0.170 0.151 0.121 0.105

Total iron 0.49 0.24 0.13 0.11 0.10 0.04 0.05 0.11 0.12 0.03

Copper 0.002 0.0004 0.0011 0.0011 0 0.003 0.0006 0 0.001 0.004

Zinc 0.003 0.0005 0.0008 0.0031 0.0007 0.0018 0.001 0.0004 0.003 0.011

Oil products 0.39 0.10 0.30 0.09 0.07 0.06 0.33 0.21 0.10 0.09

Surfactants 0.006 0.055 0.035 0.019 0.052 0.046 0.055 0.015 0.022 0.017

According to summarized data for 1985-1999 higher pollution of surface horizon is recorded for oil products and easy oxidable organic matter (in terms of BOD5) and higher pollution of bottom horizon – for nitrites, iron and copper. This is possibly due to impact of bottom sediments on water quality downstream city pollution sources and inflow of polluted ground water.

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Table 7.3 Average annual concentrations of pollutants in the Don River downstream Koluzaevo (mg/dm3)

Years Parameters 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999

Dissolved oxygen

8.89 10.67 10.53 9.74 10.76 10.04 10.22 10.04 9.42 9.90

Magnesium 48.3 39.5 44.1 42 30.3 44.8 35.2 32.7 35.7 -

Chlorides 179 121 210 157 108 151 140 145 120 -

Sulphates 234 170 241 159 111 222 242 274 323 -

Mineralization 905 640 941 725 522 813 855 1005 976 -

COD 89 54 59 78 48 17 101 52 84 -

BOD5 3.15 2.59 3.80 3.37 3.79 2.86 2.37 3.52 3.13 3.28

Ammonia nitrogen

0.038 0.063 0.241 0.76 0.213 0.375 0.161 0.285 0.24 0.41

Nitrite nitrogen 0.078 0.063 0.023 0.033 0.042 0.040 0.028 0.038 0.030 0.019

Nitrate nitrogen

0.064 0.12 0.27 0.35 0.47 0.157 0.173 0.190 0.22 0.37

Phosphates (Р)

0.099 0.128 0.127 0.059 0.108 0.099 0.197 0.134 0.129 0.102

Total iron 0.119 0.153 0.175 0.116 0.146 0.122 0.115 0.195 0.127 0.109

Copper 0.22 0.91 0.145 0.121 0.168 0.047 0.077 0.052 0.112 0.026

Zinc 0.004 0.0009

0.001 0.002 0.0003

0.0004 0.0002

0.0002 0.0006

0.003

Oil products 0.004 0.001 0.001 0.005 0.001 0.002 0.001 0.002 0.003 0.009

Surfactants 0.179 0.094 0.153 0.071 0.08 0.146 0.37 0.395 0.112 0.13

Nitrite nitrogen 0.028 0.031 0.032 0.020 0.013 0.028 0.048 0.016 0.24 0.021

Notes: “-“ no data available Conclusions based on assessment of environment state:

1. Rostov-on-Don emissions define air pollution within the WWTP. Air pollution level is poor. Only nitric oxide and carbon oxide concentrations are recorded at MAC levels. Concentrations of some heavy metals are increased in solid-phase precipitation.

2. Content of copper, iron (in summer), phenols (in summer), organic matter (BOD5), sulphates and nitrites (in winter) exceeds MAC values in the Don river water at the reach between the Tsimlyansk reservoir and river mouth. In the Don river mouth pollution increases in all seasons for sulphates (and water mineralization) and oil products; in winter - for nitrites, BOD5, iron. River reaches near towns of Aksai, Rostov, Azov are the most polluted parts (in terms of BOD5, oil products – for all seasons, nitrites - in winter, phenols - in summer).

3. Increase of anthropogenic euthrophication is periodically recorded at the mouth reach of the Don River. Maximum values of phytoplankton population are recorded in summer and autumn. At this time significant changes of community structure are registered due to modification of specific composition of dominant complex and tendency of certain species for a leading place.

4. Hygienic standards for BOD5 (1.5 – 2 MAC), COD (1.5 – 3.5 MAC), total

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hardness (1.2 – 1.5 MAC), total iron (1.3 – 5.1 MAC) and oil products (1.2-32 MAC) (data provided by Centres of Gossanepidnadzor for Rostov-on-Don, Azov, Taganrog, Azov district) are recorded in the Don river water at water intakes and in recreation zones of populated areas.

5. In terms of bacteriological pollution the Don river is regarded as a source with an increased level of epidemiologic danger. Coli-fags, spores of sulphitreducing clostridias, choleroid microflora were identified in river water. High level of river water bacteriological pollution is recorded in the Don river mouth area, especially downstream of Rostov sewage discharges and at the confluence of the Temernik and Don. Azov city water intake has the most critical situation with water quality in terms of microbiological pollution. This is due to discharge of insufficiently treated and crude wastewater of Rostov city in the Don river. Use of drinking water with bacteriological and viral pollution leads to acute enteric infections and viral hepatitis type A.

6. Chemical composition of ground water forms due to atmospheric precipitation, infiltration of technogenic water at the WWTP site, as well as pollutants washing from unauthorised dump of household and industrial wastes located in the northern part of the WWTP. Organic substances (high value of BOD5), oil products (8-58 MAC), iron (even in background zone 34.5 mg/l, 69 time shigher than MAC; in a pollution point - 112,7 mg/l or 225 MAC), and cadmium (0.035 – 0.077 mg/l) are the most typical elements of ground water pollution.

7. Level of soil pollution with heavy metals is minor. Contrast and vast lithochemical anomalies were not discovered at WWTP site.

8. Progressing drying and salination of floodplain landscapes happen due to water flow regulation and reduction of frequency and duration of floods. Chemical elements accumulate in the soils upper horizon.

9. In the zone of the Rostov industrial centre natural oxygen and oxy-gley landscapes in the Don River were transformed into oxy-hydrosulfuric under technogenesis. Increase of pollutants concentration in all landscape components, increased accumulation of organic matter at the bottom, intensification of reduction processes, their shift from sediments to near-bottom waters, flow of dissolved elements (compounds of nitrogen, phosphorous, microelements) from silts to water column will accompany this transformation.

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Chapter 8 Assessment of the proposed activity environmental impact Existing economic activity pose certain technogenic impact on environments, namely:

Air pollution; Discharge of treated wastewater into the Don River; Ground water pollution; Waste generation.

8.1 Air quality Bituminous concrete plant, trade port being under construction, terminals of Rostov port and Yug Rusi, Ltd. are key pollutants in the area of the WWTP (Table 8.1). Table 8.1 List and amount of pollutants allowed to be emitted into the air (MAE*), tons/year

Enterprise Parameter WWTP Bituminous

concrete plant Rostov port Close

corporation “Yug Rusi”

Korvet, Ltd.

Nitrogen dioxide 0.2828 1.6548 0.1753 33.1676 0.0804Nitric oxide 0.0291 0.238 0.0074 8.0087 0.0051Ammonia 0.4588 Sulfur dioxide 0.0657 5.8620 0.0953 0.4936 0.0004Carbon monoxide 3.0757 7.5420 0.4421 8.0177 0.2170Methane 5.6771 Ferric oxide 0.0035 0.2618 0.0818 0.2272Soot 0.508 0.0034 0.0286 0.0006Dust 10.191 0.3208 0.1862Grain dust 55.637 Carbohydrates 1.947 0.0012 1.378 Kerosene and petrol

0.027 0.051 0.5811 0.0056

Note: *Data presented by the Central Administrative Board on Natural Resources for the Rostov Oblast, RF Ministry for Natural Resources. According to the inventory there are 148 sources of air emissions on all Vodokanal industrial sites; 31 source of harmful substances emissions at the WWTP site 9the Don river left bank). There are 43 pollutants in emissions composition. They form 10 groups of accumulated impact. Iron and manganese oxides, nitrogen dioxide, hydrogen sulphide, chlorine, grit, wood dust, carbon oxide, methyl methacrylate, ethyl mercaptan, etc. are listed among pollutants (Figure 8.1). Air quality is affected by the following key technological processes:

Wastewater treatment; Preparation of chloric water; burning of gaseous fuel in a boiler-house; gas-welding and electrical welding operations; sharpening works;

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transport. Total amount of air emissions at the WWTP is 124,082 tons/year. In terms of meteorological conditions the WWTP area belongs to the III zone “increased potential of air pollution”. According to the Rostov Oblast Hydrometeorological Center background pollution in the area of the WWTP for suspended solids is 0.3 mg/m3, sulfur dioxide – 0.019-0.063 mg/m3, nitrogen dioxide – 0.08-0.1 mg/m3, carbon oxide – 3.0 mg/m3. Estimates of air pollution are given in Table 8.2. Table 8.2 List of parameters and sources with the largest input into pollution in the area of the WWTP

Estimated maximum ground concentration: MAC part / mg/m3

% of input Sources with the largest input

Parameter

Residential area (RA)

At the border SPZ RA SPZ

Nitrogen dioxide 0.0459/ 0.0039 0.05606/ 0.00477 45.0 50.8 Boiler-house

Ammonia 0.05148/ 0.0103 0.05847/ 0.01169 42.1 39.9 Drying beds

Hydrogen sulphide 0.25166/ 0.00201 0.2858/ 0.00229 74.7 83.9 -«-

Carbon monoxide 0.0127/0.06366 0.01448/ 0.07239 46.0 46.9 -«-

Methanethiol */0.02082 */0.02366 40.1 38.0 -«-

Ethanethiol (ethyl mercaptan)

*/0.03198 */0.03632 38.5 36.6 -«-

Ammonia */0.30137 */0.34059 73.5 82.9 -«-

Sulfur dioxide */0.25166 */0.2858 74.7 83.9 -«-

Note: * - no data. Level of maximum ground concentrations of pollutants in the WWTP emissions is not exceeded (0.03-0.34 MAC). Taking into account this results emissions from enterprise emission sources are proposed as a standard of limiting emission. Key pollutants are emitted from a surface of wastewater treatment facilities. Chlorine storage facility locates on the left bank of the Don river, in the Zarechnaya industrial zone. At the water treatment facilities chlorine is used to support facilities in a proper sanitary state (primary chlorination), to disinfect drinking water (secondary chlorination) and to disinfect wastewater. Chlorine is stored in waterproof containers (800 l capacity and 1 ton weight) under a shed. At present 100 tons of chlorine are stored at storage facility. Chlorine is transported in containers. Sources of emissions were not found at chlorine storage facility. At chlorine storage facility there is no production activity and boiler-house, thus, no pollutant emissions.

79

In terms of sanitary classification, according to SanPiN 2.2.1/2.1.1.1200-03 this storage facility belongs to enterprises of class III with a standard width of SPZ 300 m. There is no residential area near chlorine storage facility. The following is envisaged to prevent emergency emissions from chlorine storage facility: decontamination system, system of control and alarm about chlorine concentration, blocking systems providing emergency engaging of ventilation system and disconnection of technological equipment. Special activities on regulation of emissions in meteorologically unfavourable seasons are not envisaged, as pollution level is insignificant. At WWTP site recorded air emissions are 5.68 tons of methane /year (sludge drying beds and sludge storage lagoons) and 3.076 tons of carbon oxide /year (boiler-room) (see Figure 8.1). For other pollutants input of the WWTP into atmospheric pollution in the area of Zarechnaya industrial zone is very low compared to other industrial enterprises located here (Figure 8.2). If a plant for methane collection and utilisation will be installed during WWTP reconstruction, methane emissions will reduce from 14 kg/day to 4 kg/day, i.e. by 11 kg/day or by 4.04 tons/year (by 3.5 times). If collected methane will be burnt then about 68 t/day of carbon dioxide will be emitted into the atmosphere. Carbon dioxide is less toxic. "JACOB-GIBB" assessed present emissions of the WWTP gases causing green house effect taking into account gases from used electric power and coal burning at local heat station. This data was compared with estimates of emissions after the WWTP reconstruction (taking into account use of mesophilic methane tanks and heat station operating on produced biogas) (Table 8.3). Short-term forecast for 5 years (company “Jacobs GIBB”) Basic (zero) option Total volume of gases formed in a sludge – 39,179 kg/day. Gas decomposition in conditions of sludge long-term storage – 55% Coefficient of methane generation – 0,90 m3/kg of gases Methane generation from stored sludge - 19,394 m3/day Methane density - 0,72 kg/m3 Mass of generating methane 13,964 kg/day = 5,097 tons/year Required electric energy, total - 4273 kWatt,

Including: Aeration – 2827 kWatt Mixing – 661 kWatt Pumping – 384 kWatt Centrifuge – 200 kWatt Other – 200 kWatt

Needs in purchased energy, total – 4523 kWatt, Including:

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Electric energy from energy system – 4373 kWatt Thermal energy produced by gas boiler – 250 kWatt

Green house gases emissions (without СО2 from methane tanks): Methane emissions from sludge storage facility – 13,964 kg/day Global warming potential (GWP) for methane – 21 Methane emissions in hydrocarbon equivalent – 293,234 kg/day СО2 emissions from sludge storage facility – 20,086 kg/day

Purchased energy in СО2 equivalent – 205,082 kg/day Heating by natural gas in СО2 equivalent – 1,512 kg/day Total emissions in CO2 equivalent – 519,914 kg/day = 189,769 tons/year Option with anaerobic digestion of sludge and CHP construction Total volume of volatile matter in sludge – 39,179 kg/day Gas decomposition in conditions of anaerobic digestion – 50% Gas decomposition in conditions of sludge long-term storage – 10% Coefficient of methane generation – 0,90 m3/kg degradable volatile matter Methane generation in conditions of anaerobic digestion - 17,631 m3/day Methane generation from stored sludge - 3,526 m3/day Methane density - 0,72 kg/m3 Mass of methane generating in conditions of anaerobic digestion 12,694 kg/day = 4,633 tons/year Mass of methane generating from stored sludge – 2,539 kg/day = 927 tons/year Required electric energy, total - 4273 kWatt, Including:

Aeration – 2827 kWatt Mixing – 661 kWatt Pumping – 384 kWatt Centrifuge – 200 kWatt Other – 200 kWatt

Required thermal energy, total - 2840 kWatt, Including:

Absorbent heating – 2590 kWatt Other necessities (generated by gas boiler) – 250 kWatt

Energy generated by the heat power plant, total - 3320 kWatt, Including:

Thermal –1990 kWatt

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Electric – 1330 kWatt Purchased energy, total - 3793 kWatt, Including:

Electric energy from energy system – 2943 kWatt Thermal energy produced by gas boiler – 850 kWatt

Green house gases emissions (without СО2 from technological tanks) Methane emissions from sludge storage facility – 3,526 kg/day GWP for methane – 21 Methane emissions in hydrocarbon equivalent – 74,049 kg/day СО2 emissions from sludge storage facility – 5,072 kg/day

Purchased energy in СО2 equivalent – 141,242 kg/day Heating by natural gas in СО2 equivalent – 5,141 kg/day СО2 emissions of the heat power station – 53,169 kg/day Total emissions in CO2 equivalent – 278,673 kg/day. = 101,715 tons/year Long-term forecast (company “Jacobs GIBB”) Basic (zero) option Total volume of gases formed in a sludge – 50,324 kg/day Gas decomposition in conditions of sludge long-term storage – 55% Coefficient of methane generation – 0,90 m3/kg degradable volatile matter Methane generation from stored sludge - 24,910 m3/day Methane density - 0,72 kg/m3 Mass of generating methane 17,935 kg/day. = 6,546 tons/year Required electric energy, total - 5936 kWatt, Including: Aeration – 3849 kWatt Mixing – 855 kWatt Pumping – 832 kWatt Centrifuge – 200 kWatt Other – 200 kWatt Required thermal energy generated by gas boiler – 250 kWatt Total: 5936 + 250 = 6186 kWatt Green house gases emissions (without СО2 from methane tanks)

Methane emissions from sludge storage facility – 17,935 kg/day GWP for methane – 21 Methane emissions in hydrocarbon equivalent – 376,643 kg/day

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СО2 emissions from sludge storage facility – 25,799 kg/day Purchased energy in СО2 equivalent – 284,939 kg/day Heating by natural gas in СО2 equivalent – 1,512 kg/day Total emissions in CO2 equivalent – 688,893 kg/day = 251,446 tons/year Option with anaerobic digestion of sludge and CHP construction Total volume of gases formed in a sludge – 50,324 kg/day Gas decomposition in conditions of anaerobic digestion – 50% Gas decomposition in conditions of sludge long-term storage – 10% Coefficient of methane generation – 0,90 m3/kg degradable volatile matter Methane generation in conditions of anaerobic digestion - 22,646 m3/day Methane generation from stored sludge - 4,529 m3/day Methane density - 0,72 kg/m3 Mass of methane generating in conditions of anaerobic digestion 16,305 kg/day = 5,951 tons/year Mass of methane generating from stored sludge – 3,261 kg/day = 1,190 tons/year Required electric energy, total - 5936 kWatt, Including:

Aeration – 3849 kWatt Mixing – 855 kWatt Pumping – 832 kWatt Centrifuge – 200 kWatt Other – 200 kWatt

Required thermal energy, total - 3310 kWatt, Including:

Absorbent heating – 3060 kWatt Other necessities (generated by gas boiler) – 250 kWatt

Energy generated by the heat power plant, total - 4280 kWatt, Including:

Thermal –2560 kWatt Electric – 1710 kWatt

Purchased energy, total - 4976 kWatt, Including:

Electric energy from energy system – 4226 kWatt Thermal energy produced by gas boiler – 750 kWatt

Green house gases emissions (without СО2 from methane tanks)

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Methane emissions from sludge storage facility – 4,529 kg/day GWP for methane – 21 Methane emissions in hydrocarbon equivalent – 85,112 kg/day СО2 emissions from sludge storage facility – 6,515 kg/day

Purchased energy in СО2 equivalent – 202,859 kg/day Heating by natural gas in СО2 equivalent – 4,536 kg/day СО2 emissions of the heat power station – 68,292 kg/day Total emissions in CO2 equivalent – 377,314 kg/day = 137,720 tons/year Option with phosphorous chemical stripping and anaerobic digestion of sludge In case of phosphorous chemical stripping sludge volume can reduce by about 20%. Thus, total emission of “green house” gases in CO2 equivalent can increase up to 452.777 kg/day = 165.264 tons/year under a long-term forecast. Table 8.3 Estimates of air emissions under different options of the WWTP reconstruction Basic option

(without sludge

compaction) – short-term

forecast

Anaerobic digestion of sludge and

CHP – short-term forecast

Basic option (without sludge

compaction) – long-term forecast

Anaerobic digestion of sludge and CHP – long-

term forecast

Total volume of gases emitted from a sludge, kg/day

39,179 39,179 50,324 50,324

Share of decomposed gases in conditions of sludge storage, %

55 10 55 10

Gas decomposition in conditions of anaerobic digestion, %

50 50

Coefficient of methane generation from gases, m3/kg of gases

0,90 0,90 0,90 0,90

Volume of methane generated from sludge, m3/day

19,394 3,526 24,910 4,529

Volume of methane generated in conditions of sludge digestion, m3/day

17,631 22,646

Methane density, kg/m3 0,72 0,72 0,72 0,72Mass of methane generating from stored sludge, kg/day.

13,964 2,539 17,935 3,261

Mass of methane generating from stored sludge, tons/year

5,097 927 6,546 1,190 т

Mass of methane 12,694 16,305

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generating in conditions of anaerobic digestion, kg/day Mass of methane generating in conditions of anaerobic digestion, tons/year

4,633 5,951

Total of generated methane, tons/year

5,097 5,560 6,546 7,041

Required electric energy, total (kWatt)

4273 4273 5936 5936

Required thermal energy, total (kWatt)

2840 250 3310

Purchased energy, total (kWatt):

4523 3793 6186 4976

Electric energy, kWatt 4373 2943 5936 4226Thermal energy, kWatt 250 850 250 750Energy generated by the heat power plant, total (kWatt)

3320 4270

Electric energy, kWatt 1330 1710Thermal energy, kWatt 1990 2560

Table 8.3 to be continued Basic option

(without sludge

compaction) – short-term

forecast

Anaerobic digestion of sludge and

CHP – short-term forecast

Basic option (without sludge

compaction) – long-term forecast

Anaerobic digestion of sludge and CHP – long-

term forecast

Methane emission from sludge storage facility, kg/day

13,964 3,526 17,935 4,529

GWP for methane 21 21 21 21Methane emissions in hydrocarbon equivalent, kg/day

293,234 74,049 376,643 85,112

СО2 emissions from sludge storage facility, kg/day

20,086 5,072 25,799 6,515

Purchased energy in СО2 equivalent, kg/day

205,082 141,242 284,939 202,859

СО2 emissions of the heat power station, kg/day

53,169 68,292

Heating by natural gas in СО2 equivalent, kg/day

1,512 5,141 1,512 4,536

Total emissions in CO2 equivalent, kg/day

519,914 278,673 688,893 377,314

Total emissions in CO2 equivalent, tons/day

189,769 101,715 251,446 137,720

Total emissions in CO2 equivalent under option

251,446 165,264

85

of phosphorous chemical stripping, tons/day

Carbonic gas has a minor adverse impact on climate (due to global warming) than methane. According to estimates, after the WWTP reconstruction methane emissions will reduce by 70% and emissions equivalent to CO2 by 60% (34-45%). Thermal and electric energy generated by the proposed CHP will be used at site. This will significantly reduce use of electric energy purchased from the Novocherkask power plant operating on coal. Reconstructed WWTP will require more energy than existing mainly due high-energy consumption of digesters and dewatering plants. If methane generated in methane tanks will be unused then all electric energy will have to be purchased in the market. It is difficult to make accurate quantitative estimates but it is clear that construction of the CHP will allow to reduce consumption of coal required for energy production. This will decrease emissions of CO2, solid particles and accumulation of coal ash. Air quality will significantly improve both at the WWTP site and in the Greater Rostov area. 8.2. Impact on surface water quality 8.2.1. Zero option – no reconstruction. Existing anthropogenic load on the Don river between Rostov-on-Don and the Taganrog Bay. The following contributes to water quality formation and environmental situation in the Don River at the reach between 65th km and river mouth:

chemical substances received with water from site located upstream Rostov; chemical substances received with waters of tributaries (rivers Aksai, Temernik,

gullies Bezymyannaya and Kiziterinovka); surface run-off from adjacent arable lands; surface run-off from populated settlements, including Rostov; wastewater of different industrial enterprises; municipal wastewater.

As mentioned above, higher concentrations of ammonia nitrogen, nitrite nitrogen, sulphates, total iron, oil products and phosphates are recorded upstream Rostov-on-Don. The Temerink river is the most polluted tributary of the I order. Key pollutants are easily oxidable organic matter (in terms of BOD5), ammonia nitrogen, oil products, anion active surfactants, total iron and aluminium. Discharges of untreated wastewater (6,570 thounsand m3/year) by Rostov Vodokanal have a major impact on the Temernik river pollution. Thus, pollution of riverine water increases. Existing situation with the Temernik river indicates that river rehabilitation is possible only if discharges of untreated wastewater by Rostov Vodokanal will be eliminated and river will be isolated from unauthorized rainwater and other municipal and industrial wastewater. Also riverbed dredging from bottom sediments being source of secondary pollution will contribute greatly to reduction of the Don river pollution level. Uzgeologiya data for 1989 – 1992 gives general idea about surface run-off pollution

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(Table 8.4). High pollution of surface water streaming down into the Don river along gullies located in Rostov should be expected for all substances listed in Table 8.4, except for phenols. Table 8.4 Content of pollutants in surface water in the Leninsky district, Rostov-on-Don

Concentration in water of the surface flow, mg/l Parameter melting rainfall

рН 6,8-9,6 -Phenols n/d -0,007 n/d -0,007Oil products 0,3-14,3 0,3-8,0Surfactants 0,03-0,76 0,15-0,57Zinc 0,2-5,2 0,1-1,5Copper 0,01-0,07 0,02-0,25Manganese 0,2-5,8 0,03-0,74Aluminium 0,3-19,0 0,5-5,9Lead - 0,03-0,74Chromium - n/d -1,6Total iron n/d -2,8 n/d -3,10Ammonia nitrogen 0,39-69,8 0,93-9,3Nitrate nitrogen n/d -2,8 n/d -5,2Chlorides 98-2472 7,1-213Mineralization 398-6552 244-920

Note: “-“ no observations; n/d – substance not identified. Wastewater of different enterprises is one of the strongest pollution sources of the Don river. Considerable portion of industrial wastewater arrives to Vodokanals’ WWTP where it is subject to different treatment methods. However, operation of treatment facilities is not always efficient and insufficiently treated water containing pollutants with an adverse environmental impact are discharged into the river. General data on wastewater discharges for the reach between 65-18 km and river mouth is given in Table 8.5 in terms of enterprise, category of wastewater, volume of discharged water. Total amount of discharged wastewater is 170 million cubic meters. Table 8.5 Data on wastewater discharges into the Don River at the reach 0 – 65 km, million cub. m

including Pollution Standard- including

Without treatment

Insuffic. treated

Without treatment

Normatively clean Treated

Enterprise

TOTAL

TOTAL

Biologically treated

Physically-chemically treated

Mechanically treated

AZOVRYBA /Fish plant/ Azov

0.76700 - - 0.76700 - - - -

AZOVVODOKANAL, Azov 11.4330 - 0.80700 3.50300 7.12300 6.46400 - 0.65900

Rostoselmash, Rostov 0.07500 - 0.07500 - - - - -

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EMPILS, Rostov 0.01400 0.00200 - 0.01200 - - - -

ROSTOVTEPLOSET (branch of Rostovenrgo), Rostov

0.06500 0.06500 - - - - - -

RABOCHII, Rostov 0.19900 - - 0.19900 - - - -

BALTIKA-DON ("Don Pivo"), Rostov

0.00500 0.00500 - - - - - -

Rostov VODOKANAL 119.563 12.8550 106.708 - - - - -

Semikarakorskoye UOS 1.79400 1.79400 - - - - - -

Azovsky MUOS 2.48000 2.48000 - - - - - -

Fish Plant “VZMORIE”, Kagalnik Azovsky

0.70000 - - 0.70000 - - - -

"Kuleshevka Fish farm " Azov district, Ust settlement

4.90000 - - 4.90000 - - - -

KAZACHKA, Aksai district (Fish farm)

15.7140 - - 15.7140 - - - -

Fish farm named after Kirov, Aksai, Aksai district

2.61900 - - 2.61900 - - - -

Fish farm named after Miroshnichenko, Rostov

1.57900 - - 1.57900 - - - -

Fish farm named after Lenin, Azov district, settlement Kurgany

1.46000 - - 1.46000 - - - -

Fish farm named after CHKALOV, Azov district, settlement Dugino

3.05500 - - 3.05500 - - - -

AKSAISKY MRUOS, Aksai

1.23400 - - 1.23400 - - - -

Fish Famr, Kuleshovka settlement, Azov district

1.12300 - - 1.12300 - - - -

AKSAI-INTER, Aksai 0.00100 - 0.00100 - - - - -

GEDON-SPORT 4.20000 - - 4.20000 - - - -

Branch OKTYABRSKY of ROSTOVUGOL (coal mining)

1.25700 - 1.25700 - - - - -

Of the total volume of wastewater about 10% is water “polluted without treatment”, 62% - “polluted insufficiently treated”, 23% - “normatively clean without treatment”, 4% - normatively treated” (Table 8.5). Rostov Vodokanal has the largest input both in total wastewater discharges (68%) and in discharges of “polluted insufficiently treated” water (98%) (Table 8.5). Water discharge at Rostov Vodokanal amounts to 68% of total water discharge at this river reach. Vodokanal discharges municipal and industrial wastewater from two water outlets: No. 1 – from the WWTP into the Don river, No. 2 – untreated wastewater into the Temernik river. Rostov Vodokanal WWTP discharges wastewater into the Don river from water outlet No. 1 located 38 km from the river mouth and along dispersive outlet located 80 m from the navigation canal centreline and 150 m from the left bank in high water period. WWTP (Phases I and II) is located on the left bank of the River Don, 100 m from the coastal line. From the works wastewater is transferred under the pressure via three concrete conduits (∅1400) to the discharge works (6.5 km). Discharge works consists of two runs of steel pipes (∅1200×14). Dispersive device with 8 heads (∅3500) locates at the end of each pipe.

88

In terms of specific character 77% of wastewater is municipal and 23% is industrial. Wastewater category is insufficiently treated. The following enterprises use the Vodokanal WWTP: 32 food industry enterprises; 43 – machine-building and metal processing; 22 – chemical industry; 24 – construction industry; 19 – electronics industry; 20 – light industry; 59 – transport industry; 3 – wood industry and 5 – fuel-energy industry. The WWTP (Phases I and II) were set into operation in 1976 and 1986, respectively; total designed capacity is 440,000 m3/day. However, due to a change in wastewater treatment norms the present peak daily flow to treatment was calculated at 313,000m3/day. Amount of pollutants and composition of wastewater discharged by the Rostov WWTP is given in Table 8.6. Table 8.6 Amount of pollutants and chemical composition of Rostov Vodokanal wastewater discharged into the Don River (RVK data)

Wastewater parameters

Pollutants background concentrations in water body, mg/dm3

Actual pollutants concentrations at site of wastewater discharge, mg/dm3

Actual discharge of pollutants into a water body, gr/hour

Maximum permissible concentration of pollutants at site of wastewater discharge, mg/dm3

Maximum permissible discharge of pollutants into a water body, gr/hour

Required change of actual pollutants concentration at discharge site, mg/dm3

Suspended solids 13.2 55 1042030 15.0 284190 40Dry residue 821 1400 26524400 1000 18946000 400Chlorides 121 281 5323826 281 5323826 0Sulphates 255 360 6820560 255 4831230 105Magnesium 36 53 1004138 53 1004138 0BOD5 3.04 47 890462 3.04 57595.8 43.96COD 24.1 80 1515680 24.1 456599 55.9Ammonia nitrogen 0.21 6.13 116139 1.35 25577 4.78Nitrite nitrogen 0.05 0.85 16104.1 0.05 947.3 0.80

Table 8.6 to be continued

Wastewater parameters

Pollutants background concentrations in water body, mg/dm3

Actual pollutants concentrations at site of wastewater discharge, mg/dm3

Actual discharge of pollutants into a water body, gr/hour

Maximum permissible concentration of pollutants at site of wastewater discharge, mg/dm3

Maximum permissible discharge of pollutants into a water body, gr/hour

Required change of actual pollutants concentration at discharge site, mg/dm3

Nitrate nitrogen 1.42 5.50 104203 5.50 104203 0Phosphorous phosphates

0.18 1.7833723.9 0.2

3789.2 1.58

Total iron 0.29 0.81 15346.3 0.29 5494.34 0.52Copper 0.004 0.039 738.894 0.004 75.784 0.035Zinc 0.004 0.041 776.786 0.035 663.11 0.006

89

Total chromium 0.011 0.07 1326.22 0.07 1326.22 0Manganese 0.053 0.05 947.3 0.05 947.3 0Aluminium 0.31 0.035 663.11 0.035 663.11 0Nickel 0 0.11 2084.06 0.020 757.84 0.07Lead 0.005 0.029 549.434 0.006 113.676 0.023Cadmium 0 0.008 151568 0.001 18.946 0.007Surfactants anion 0.40 1.10 20840.6 0.1 1894.6 1.0Surfactants non-ion 0 0.46 8715.16 0.46 8715.16 0Oil products 0.41 0.78 14777.88 0.05 947.3 0.73Phenols 0 0.0007 13.2622 0.001 18.946 0Sulphides 0 0 0 0 0 0Fluorides 0.30 0.44 8336.24 0.44 8336.24 0

Analysis of pollutants in wastewater of enterprise discharging into the Don river at the studied reach (Table 8.7) shows that Rostov Vodokanal input in pollution is the largest among point sources. Table 8.7 Volume of pollutants in wastewater discharged by Rostov Vodokanal Pollutants Mass of discharged

substances, tons Share in total amount of substance input, %

BOD5 4506 97.8Ammonia nitrogen 412.6 95.4Nitrates 10.2 10.6Nitrites 56.6 90.7Phosphates 88.5 85.9Suspended solids 4308 87.6Surfactants 16.6 99.4Oil products 24.4 84.7Total iron 33.8 89.7Sulphates 4135 35Chlorides 9600 65.9Aluminium 1.18 91.4Copper 1.69 86.1Zinc 1.61 93.5Total chromium 1.24 94.5

Thus, the Temernik river water and Rostov Vodokanal effluents pose the major pollution impact on the Don river in its lower reaches. Impact on the Don river hydrochemical regime Long anthropogenic impact led to transformation of water chemical composition due to increase of pollutants concentration (ammonia nitrogen, nitrites, easily oxidable substances, oil hydrocarbon, copper and zinc compounds. The tensest river reach is between Rostov-on-Don, downstream Vodocanal discharges and Koluzaevo settlement. Repetition factor of MAC exceedence for ammonia nitrogen is 5.1-7.2; nitrite nitrogen - 5.4-9.2; oil hydrocarbon - 7.2-14; copper - 7-8. These are of the major importance for any activity resulting in change of nutrient and organic matter.

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Dynamics of nitrogen and phosphorous, BOD5 was studied based on analysis of long-term observations (1990-2002) of their spatial variation in the Don river water (up to the river mouth). Content of nitrogen and phosphorous compounds and organic matter in the Don river water is given in Table 8.8. Table 8.8 Variation of nitrogen and phosphorous compounds and organic matter (in terms of BOD5) (numerator) and their average values (denominator)

Nitrogen, mg/l Observation site BOD5, mg/l Ammonia Nitrite Nitrate

Phosphorous phosphate, mg/l

Rostov, upstream 1.08-7.05

4.01 0.06-0.88

0.30 n/d-0.124

0.026 0.01-1.18

0.28 0.024-0.440

0.14 Rostov, downstream the WWTP discharge site

1.00-7.97 4.32

0.06-0.87 0.29

n/d -0.138 0.032

0.01-0.96 0.28

0.010-0.656 0.14

settlement Koluzaevo 1.00-7.02 3.19

0.06-0.76 0.27

n/d -0.200 0.039

0.06-0.69 0.26

0.010-0.656 0.124

Azov 1.25-8.57 3.58

0.13-0.98 0.37

n/d -0.138 0.040

0.08-1.52 0.25

0.011-0.736 0.140

B. Kalancha – settlement Dugino

1.03-5.71 3.13

0.04-0.96 0.14

n/d -0.218 0.040

n/d -0.92 0.30

n/d -0.316 0.118

For 1990 – 2002 concentrations of easily oxidable organic matter changed from 1.25-8.57 mg/l near Azov to 1.03-5.71 mg/l near B. Kalancha branch. In terms of average values they increase near Rostov, downstream wastewater outlet and increase towards the river mouth. In terms of spatial variation ammonia nitrogen and nitrite nitrogen slightly increase towards the river mouth. Average values of mineral phosphorous concentration vary insignificantly from 0.118 mg/l near B. Kalancha branch to 0.145 mg/l upstream Rostov. However, variation range increases from Rostov, upstream Azov and decreases in B. Kalancha branch. Accumulation of nutrient elements in water was considered as initial parameter of potential eutrophication of water ecosystems. Thus, conditions favourable for anthropogenic eutrophication intensification form at river reaches. Estimated assessment of the WWTP input in increase of nutrient and organic matter in the Don river water is given in Table 8.9. In water flow of the Don river near Aksai town is 52.6 million m3/day, then volume of the WWTP wastewater will be 292.3 thousand m3/day. At present due to inflow of the WWTP wastewater content of nitrite nitrogen in the Don river water increases by 23%, nitrate nitrogen – by 14%, phosphorous – by 7%, organic matter – by 1.7%. Impact on the Don river hydrobiology regime Statistical processing of information on qualitative parameters of phytoplankton development in the Don river water between Rostov and river mouth shown that process

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of anthropogenic eutrophication is restrained by toxic effect of water environment on phytoplankton development. Table 8.9 WWTP input in increase of nutrient and organic matter in the Don river water

Nitrogen Parameter BOD5 Ammonia Nitrite Nitrate

Phosphorous phosphate

Average content, mg/l: In treated WWTP effluents

20.8 3.5 1.58 11.03 2.64

In the Don River upstream Rostov-on-Don

4.01 0.30 0.026 0.28 0.14

Discharge with the WWTP wastewater, kg/day

6080 1023 301 2391 773

Flow into the Don River upstream Rostov-on-Don, kg/day

210000 15800 1370 14730 7630

Flow into the Don River downstream the site of WWTP effluent discharge, kg/day

216080 16823 1671 17121 8403

Estimated content in the Don River water downstream the site of WWTP effluent discharge, mg/l

4.08 0.32 0.032 0.32 0.16

WWTP input in increase of content in the Don River water, %

1.7 6 23 14 14

Growth of plankton population and reorganisation of group/specific structure in compliance with each species’s tolerance level and, mainly, due to fall out of oligo- and mesosanprobes, are recorded if anthropogenic eutrophication will intensify due to water enrichment with nutrient without any restrictive conditions. Reorganisation of group/specific structure is. Reduction of development level and diversity of water species is a result of anthropogenic toxic impact on ecosystems. Increase of such a load could result in ecosystem death through ecological and metabolic regression. Phytoperiphiton is the most informative parameter of microsystem response on anthropogenic impact at different the Lower Don reaches. Due to location on substratum it allows to assess pollution of aquatic system for certain period of time and deterioration of aqueous medium quality. Dominating role of α-sanprobe species Navicula cryptocephala and Navicula menisculas indicates long anthropogenic pollution with municipal and industrial effluents with high content of mineral forms of nitrogen and phosphorous. Parameters of macrobenthos development are the most prospective for indication of

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consequences of the river ecosystems pollution. This is due to the fact that macrobenthos locates at certain substratum and is relatively slow-moving compared to quickly diffusive pollutants. The Don river bottom downstream Rostov is assessed as dirty and very dirty (in compliance with water quality classification in terms of hydrobiological parameters adopted in a state observation system and in terms of macrobenthos development). Results of biotests with use of different test-objects shown that:

water in the Don river lower reaches, except for the river mouth, is toxic for all test-objects (Daphnia, algae, infusorium, Rotifera) used;

toxicity was recorded in respect to all test-objects used, thus, different links of trophic chain of aquatic ecosystem experienced anthropogenic toxic pressing;

sometimes water at a reach upstream Rostov – Koluzaevo settlement was posing an acute toxic impact on Daphnia.

Thus, water was polluted by toxic chemical substances before discharged from the Temernik river and Rostov Vodokanal. Impact of these pollution sources created additional load on river aquatic ecosystem. Taking into account complexity of factors defining levels of nitrogen and phosphorous in ambient water it is difficult to assess effect from reduction of concentrations on development of biota and aquatic ecosystems under different reconstruction options. Based on the data received it should be stated that if the present situation will remain (zero option) then adverse tendency in evolution of population and species composition of hydrobionts will remain with further degradation of the Lower Don ecosystem. However, even minor decrease of nutrient and organic matter concentrations has to ensure restoration or preservation of the existing system equilibrium within permissible fluctuations of its state, i.e. within its self-regulation. This method of hydrobiological analysis will assist to trace trends in change of hydrochemical situation and to assess project goals achievement, as well as will help to prove or disprove accuracy of objectives definition. Impact on the Don river aquatic ecosystems Studied reach of the Don river is pre-mouth and mouth area with slow current velocity and accumulation of undersize suspended particles. Natural conditions contribute to substances accumulation and precipitation. Major part of pollutants carried out from the upstream parts of the watershed concentrates at this river reach. Pollutants from anthropogenic sources located between Azov and river mouth, including large industrial center - Rostov accumulate here as well. Thus, at this river reach influence vector of natural and anthropogenic factors coincides. Effect of matter accumulation summation both from sources located upstream and sources located in the studied area is recorded. Reducing hydrosulphuric conditions formed in sludgy bottom sediments as a result of anthropogenic impact (mainly due to inflow of large amount of organic matter). Oxy-gley landscapes were replaced by oxy-hydrosulfuric. Reduction processes often shift from sediments to near-bottom waters and sediments transform into a source of secondary pollution. At this reach aquatic landscapes have minimal stability to anthropogenic impact.

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Insufficiently treated water of Rostov Vodokanal poses significant impact on transformation and pollution of aquatic landscapes. Most intense rehabilitation conditions are in landscapes located downstream the Temernik river confluence and downstream the WWTP wastewater discharge. Assessment of anthropogenic impact on the Don river indicates that in order to improve environmental situation it is necessary to mitigate anthropogenic impact both at the river reach between Aksai and river mouth, and in the areas located upstream. 8.2.2. Option with biological treatment, wastewater advanced treatment and phosphorous chemical stripping During reconstruction of the Rostov WWTP their capacity should be increased up to 460,000 m3/days with wastewater treatment in compliance with requirements and conditions of their discharge into the Don river being water body of category 1 of fisheries and drinking water supply purpose. Meeting requirements of the “Rules of surface water protection from pollution” for a water body of category 1 of fisheries importance is a condition of the WWTP wastewater discharges into the Don River. Requirements to treated wastewater satisfy requirements to a water body. With account of maximum allowable concentrations of pollutants in control section, as well as background concentrations in river water content of pollutants in wastewater should not exceed values given in Table 8.10. Table 8.10 Assumed and required concentration of pollutants in the WWTP wastewater

MAC in water for water bodies, mg/l

Pollutants Content in wastewater received by the WWTP, mg/l

Content in wastewater after treatment with deep nitrification – denitrification, mg/l

Level of wastewater treatment, %

MPD, mg/l

drinking

fisheries

BODtotal 230 3 98.7 3 3 3Ammonia nitrogen

22 0.39 98.23 0.39 2 0.39

Nitrate nitrogen 9.1 9.1 10.24 9.1Nitrite nitrogen 0.2 0.02 90 0.02 0.825 0.02Phosphates (Р) 9.6 (4.22) 0.46 (0.2) 95.21 0.46 (0.2) 0.46 (0.2)

Biological treatment of wastewater with advanced treatment is required to achieve concentration of organic matter (in terms of BODtotal) - 3 mg/l and of suspended solids - 3 mg/l. Reduction of total nitrogen from 22 mg/l to 9.51 mg/l will require denitrification process; reduction of phosphates (P2O5) from 9.6 mg/l (in terms of phosphorous - 4,22 mg/l) to 0.2 mg/l in terms of phosphorous will require reagent removal. Reagent will be introduced to the trough before pre-aerators. Technological treatment scheme has to include the following processes:

mechanical treatment: grates - grit traps - primary settlement tanks; biological treatment: anoxic zone (denitrificator) – aeration zone (nitrificator) –

settlement tank for sludge suspension with installation of lamella modules; advanced treatment and effluents disinfection: bioreactor for advanced treatment

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with immobilised microflora - (Phase I) - sand filters (Phase II) - aerator trough as bubbling facility - chlorination plant, later will be UV-disinfection plant.

Proposed level of the WWTP wastewater treatment is defined by requirements of the “Rules of surface water protection from pollution” for a water body of category 1 of fisheries importance and meets them. Reconstructed Rostov WWTP envisages major reduction of pollutants discharged into the Don river with wastewater. This allows to achieve reduction of pollutants concentration in a control section (section of full mixture of natural and waste water) up to the level in a background section (500 m upstream a discharge place). This will be:

ammonia nitrogen – 0.21 mg/dm3; nitrite nitrogen - 0.05 mg/dm3; nitrate nitrogen - 1.42 mg/dm3; phosphates – 0.18 mg/dm3; BOD5 – 3.04 mg/dm3.

Background concentrations of pollutants were estimated based on statistically processed data presented by Vodokanal. Tentative estimates of nutrient and organic matter run-off into the Don river upstream and downstream the WWTP with use of average annual values in the Don river water and designed content in the WWTP wastewater after their reconstruction are presented in Table 8.11. Table 8.11 Assessment of the WWTP input after their reconstruction in increase of nutrient and organic matter in the Don river water (option with P stripping)

Nitrogen Parameter BOD5 Ammonia Nitrite Nitrate

P phosphate

Average content, mg/l: In treated effluents of the WWTP after reconstruction

3.0 0.39 0.02

9.1 0.46

In the Don river water upstream Rostov

4.01 0.30 0.026 0.28 0.14

Discharge with the WWTP wastewater after their reconstruction, kg/day

1380 179 9.2 4186 212

Flow into the Don river upstream Rostov, kg/day

210,000 15,800 1370 14,730 7,630

Flow into the Don river downstream of the WWTP discharge site, kg/day

211,380 15,979 1379 18,916 7,842

Estimated concentration in the Don river water downstream of the WWTP discharge site, mg/l

3.99 0.30 0.026 0.35 0.15

Input of the WWTP in increase of content in the Don river water, %

0 0 0 25 7

Thus, after the WWTP reconstruction under this option the WWTP input in the Don river water pollution in terms of nitrite nitrogen, ammonia nitrogen and organic matter can be reduced from 23%, 6% and 1.7%, respectively, up to a zero. Content of these substances in treated wastewater will be equal or less than content in riverine water.

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Input in terms of phosphorous will reduce twice, i.e. from 14% to 7%. Input in terms of nitrate nitrogen will increase from 14% to 24% due to transformation of recovered forms into oxidated. After treatment estimated concentrations of nutrients and organic matter in ambient water downstream effluent discharge after deep treatment will reduce insignificantly: for nitrite nitrogen - from 0.32 to 0.26 mg/l, and for phosphorous - from 0.16 to 0.15 mg/l. The proposed option will provide high level of wastewater treatment. In this case content of pollutants will comply with stated maximum permissible discharges and existing regulatory documents. Disadvantages of this method are high cost of the WWTP reconstruction, more complicated technology of wastewater treatment and additional costs required for phosphorous chemical stripping. The Temernik river flows into the Don river at 44 km from the river mouth (upstream the WWTP wastewater discharge place – 38 km). Key parameters determining pollution level of the Temernik river are easily oxidable organic matter (in terms of BOD5), ammonia nitrogen, oil products, anion active surfactants, total iron and aluminium. Significant decrease of the Don river pollution could be expected both as a result of Vodokanal wastewater treatment and rehabilitation of the Temernik river (exclusion of discharges of untreated wastewater by Rostov Vodokanal, isolation of unauthorized rainwater, municipal and industrial wastewater, dredging of bottom sediments being sources of the secondary river pollution). In future river water quality may change after the WWTP reconstruction due to activities implemented between Rostov and river mouth. Improvement of water organisms habitat, including fish populations could be expected as a result of partial removal of nitrogen-containing compounds and transfer of nitrogen from ammonium into oxidated forms (NO3) which are less toxic for biocenosises. Decrease of organic substances and nutrients discharges will result in decrease of reduction processes intensity. Oxidised layer preventing entry of pollutants from bottom into water column will remain longer on bottom sediments surface. Effective disinfection of treated wastewater will reduce the Don river bacteriological pollution. However, in order to improve water quality downstream Rostov in terms of microbiological parameters it is necessary to discontinue discharges of crude (untreated) wastewater into the Temernik and Don rivers, and to construct storm water sewer. Indicated activities will significantly reduce microbiological water pollution at water intakes located downstream Rostov; discontinue use of drinking water hyperchlorination in Azov and Azov district; reduce sickness rate of enteric infection of bacteriological/viral nature, and allow wider use of the Lower Don as a recreational zone. Taking into account complexity of factors defining levels of nitrogen and phosphorous in ambient water it is difficult to assess effect resulted from concentrations reduction on development of biota and aquatic ecosystems. However, even minor decrease of nutrient and organic matter concentrations has to ensure restoration or preservation of the existing system equilibrium within permissible fluctuations of its state, i.e. within its self-regulation. 8.2.3. Option with nutrients reduction only with biological treatment of wastewater This option is intermediate between two options described in sections above. If this option to be implemented the WWTP input in the Don River water pollution in terms of

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organic matter, nitrite and ammonia nitrogen, and phosphorous will reduce by 1.5-2 times compared to the existing situation. This will reduce estimated concentrations in ambient water downstream effluent discharge place for organic matter by 0.04-0.05 mg/l, for ammonia nitrogen – by 0.01 mg/l, for nitrite nitrogen – by 0.003 mg/l, and for phosphorous - by 0.005 mg/l. Disadvantage of this option is a low level of wastewater treatment preventing achievement of maximum permissible discharges values and meeting existing requirements to effluents discharged into category 1 water bodies used for fishery and household/drinking purposes. This option advantages are less costs for the WWTP reconstruction and operation, more simple technology of wastewater treatment. 8.3 Impact on ground water During the WWTP reconstruction it is planned to reduce volume of sludge stored at sludge drying beds and sludge storage lagoons. Less sludge and storm water enriched with organic and other pollutants will be filtered into ground water. This will contribute to reduction of ground water pollution. System’s efficiency is impeded by lack of capacities of final settlement tanks. Risks associated with use of lamella modules cause significant anxiety. Estimates shown that studied approach with installation of lamella modules is over optimistic and does not consider different risks associated with system operation. It is necessary to envisage increase of sludge processing capacity by 20-30% as it is expected that amount of sludge produced will increase due to phosphorous chemical stripping. 8.4 Impact on soil and underlying rocks Planned reconstruction of the WWTP will not contribute to increase of soil and underlying surface pollution, as well as technogenic flows contacting with soils will have less pollutants. All reconstruction and construction activities will be held within the WWTP limits. Thus, use of new lands for construction is not planned. Foundation pit will be dug during the CHP construction. Grounds filled for industrial site will be extracted for organisation of ground pit. Natural soil layer is yet not formed here. Soil protection will be organised through land improvement: access roads, footpaths, inside spaces will be covered with waterproof asphalt carpet. Transport will be moving along specially organised roads providing safe traffic without disturbance of vegetation and soil cover. All places of waste storage are protected from precipitation impact. 8.5 Impact on vegetation and fauna Involvement of new sites into operation is not planned, so, during construction works adjacent natural landscapes will not degrade. After the WWTP reconstruction reduction of agrochemical and hydrochemical load on neighbouring landscapes with decrease of atmospheric emissions and reduction of filtering sludge water will be beneficial for growth of floodplain ecosystems’ vegetation cover and fauna. 8.6 Impact of waste The WWTP sludge is the largest in terms of volume. It is the most problematic and priority waste of the WWTP. This sludge consists of primary sludge and surplus activated sludge. Safe handling exists for other types of dangerous and safe waste generated at the

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WWTP site. This includes collection, temporary storage and transfer of waste to specialised enterprises regulated by Permissions on waste production and by limits on waste disposal. At present total amount of produced sludge consists of 1220 m3/day primary sludge and 1355 m3/day surplus activated sludge. Sludge (mechanically dewatered or dried at drying beds and kept in natural conditions for not less than 2 years) has a moisture content of 54-58% respectively and is regarded as waste of class IV danger. Content of organic matter in sludge varies (in terms of dry matter) over the range of 45-47%, total nitrogen – 3.2-2.5%, phosphorous in terms of Р2О5 – 3.5–3.4%. Environmental impact of the WWTP waste is due to the aggregate exposure of the following factors:

volume of generation; qualitative composition; ways of processing; ways of disposal; ways of further use.

Proposed volume of sludge is given in Table 8.12. Additional volume of sludge generated as a result of phosphorous chemical stripping is given in the Table, as well as volume of generated sludge. UK experience shows that phosphorous chemical stripping up to 1 mg/l will increase sludge volume by 20%. Table 8.12 Estimated volume of sludge, m3/day

Sludge type Without removal of P with chemical reagents

With chemical reagents for removal of P

Primary sludge 1 220 1 220 Activated sludge 3 641 4 550 Total 4 861 5 770

Three alternative options were selected for environmental impact assessment. Implementation of alternative options will not result in qualitative and quantitative change in type of waste generated outside main technological process of wastewater treatment. Thus, only those types of waste, which composition and quantity will change within construction and reconstruction, i.e., the WWTP sludge and construction waste will be considered in this section. 1. Zero option – no reconstruction If existing situation remains then environmental impact of production and consumer waste on the WWTP will gradually increase due to:

a limited space for temporary and constant disposal of the most large-tonnage of less dangerous enterprise waste – the WWTP sludge, and, as a consequence, their accumulation at the WWTP site and growing environmental impact;

a larger content of nutrient in sludge leading to increased emissions of greenhouse

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gases. 2. Option with nutrients reduction only with biological treatment of wastewater Option providing reduction of nutrients only with biological treatment includes various construction activities: reconstruction of secondary settlement tanks, installation of lamella settlers, construction of sludge digesters and construction of CHP plant. This will result in a short-term local impact of large masses of soil on soil cover at the WWTP site and in a possible minor impact on ground water. Impact will stop after completion of building and assembly works, after construction of tank support walls from extracted soil, and covering area. Quantity of screenings will increase with operation of reconstructed WWTP. Their impact will not increase due to potential disposal to the Rostov landfill site. Sludge volume will increase after full biological treatment of wastewater. Then all produced sludge will pass through a closed cycle to the sludge digesters which will minimise the amount of sludge produced. This in combination with reduction of nitrogen, phosphorous, BOD determines potential decrease of sludge negative impact on air, soil, surface and ground water compared to the “zero” option, mainly due to a decrease of greenhouse gases emissions. 3. Option with phosphorous chemical stripping Volume of the WWTP sludge will increase in case of phosphorous chemical stripping. Sludge increase will depend on selected reagent and its dosing. At present due to later sludge digestion and dewatering total volume of sludge compared to the existing situation either will remain the same or will increase insignificantly without growth of anthropogenic load on environment but limiting possibilities of sludge use. It will be possible to reduce load on air and ground water due to qualitatively new parameters of produced sludge and gradual processing of earlier accumulated sludge from the existing sludge storage lagoons. 8.7 Environmental conditions for project implementation For the studied area environmental limitations are compliant to norms of maximum permissible emissions taking into account inputs in background pollution; maximum permissible discharges in compliance with conditions of their diversion into the Don River as water body of the 1 category in terms of fisheries and household-drinking purposes, as well as limited disposal of waste in compliance with existing permissions. There are no special limitations: the WWTP is located outside the Don river water protection zone; nearest accommodation locates outside sanitary-protection zone (1000 m). As there are no special environmental limitations for the WWTP reconstruction, development of draft document by the RF MNR on agreement of the List on environmental conditions for completion of preparation and implementation of the project results will be not required.

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Chapter 9 Measures on mitigation and/or reduction of adverse environmental impact of the proposed activity The majority of the potential adverse environmental impacts during reconstruction of the WWTP can be minimised through adherence to proper site practice and health and safety procedures and through proper requirements on dangerous waste collection, temporary storage and transportation. 9.1 Proposals on mitigation of risks due to toxic gases emissions Construction works may increase level of air pollution due to emissions from operation of car engines and mechanisms. But this impact will be local and its impact will be limited with borders of the WWTP sanitary protection zone. As a result of the WWTP reconstruction methane emissions will be significantly reduced; risk of air pollution up to a dangerous level will be reduced as well. Special additional measures on reduction of air pollution are not required. 9.2 Proposals on mitigation of adverse impact on the Lower Don aquatic ecosystems as a result of the WWTP reconstruction Construction works may have a minor deterioration in level of wastewater treatment due to interruption of processing lines. But possible this will be a minor impact because the works used at present have excessive capacity. Construction works may have minor negative impacts on surface water and air quality through operation of cars and machinery (air emissions, spillage of petroleum products, etc.). Impacts can be mitigated through correct choice of fuel and plant maintenance, by spill control procedures and by control of polluted grounds collection and utilization. 9.3 Proposals on mitigation of risks associated with ground water pollution The construction of buildings, tanks and underground pipelines may have an impact on the groundwater regime. This impact may be assumed to be negative (in disruption of existing groundwater flows) but the level of impact is likely to be marginal and no mitigation measures would be required. However borehole monitoring should be instituted where there is likely to be groundwater diversion or rising water tables. Measures on optimization of environmental situation have to be developed. 9.4. Proposals on mitigation of risks associated with the WWTP sludge storage Risks associated with waste disposal could be significantly mitigated if a proper system of waste use is implemented at an enterprise. According to the existing Russian system generated and accumulated dewatered or dried WWTP sludge is considered as waste of low danger class. According to GOST P 17.4.3.07-2001 “Nature protection. Soil. Requirements to wastewater sludge if used as fertilizers” and SanPiN 2.1.7.573-96 “Hygienic requirements to use of wastewater and their sludge for irrigation and as fertilizer” sludge can be used as organic fertilizer in agriculture, industrial flower-growing, laying out of parks and foresting. In accordance with item 6.8 SanPiN waste water sludge and compost could be used as fertilizers for lands used for planting of shrubs and trees, for parks, perennial cultural grasslands and pastures, for growing industrial crops, silage, and for land reclamation. It is prohibited to apply sludge in soils in water protection zones and reserves; on soils in forests, forest parks, pastures and hayfields.

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Norms for sludge application are set depending on their fertilizing value and content of heavy metals in soils and sludge. It is prohibited to apply sludge if heavy metals concentration exceeds norms fixed in SanPiN. If prescribed figures are exceeded then it is allowed to prepare composts based on sludge mixture with other components (peat, manure, vegetative waste) with reduction of heavy metals concentration up to levels prescribed. SP 1.2.1170-02 “Hygienic requirements to safety of agrochemicals” defines procedure of sludge preparation and application as fertilizers. According to SP 2.1.7.1038-01 “Hygienic requirements to organisation and management of MSW landfills” sludge can be disposed at the MSW landfills in the amount of 30% of MSW mass. System for the WWTP sludge management has to be developed at the works. It has to ensure meeting of the existing environmental requirements and norms, as well as to mitigate total adverse environmental impact. The following principles should form basis of such a strategy:

Health protection, support and rehabilitation of environment; Scientifically justified combination of environmental and economic interests of an

enterprise; Minimization of waste generation and minimization of their final disposal at the

WWTP site; Maximum involvement of waste into activity.

Implementation of all the priorities is possible under development of infrastructure for waste management, formation of databank of potential waste users and creation of the WWTP sludge market, and under creation of information system in the sphere of the WWTP sludge management.

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Chapter 10 Environmental consequences of possible emergency situations

Situation Problem Solution

Explosion of biogas in methane tanks with sludge

1. Destruction of methane tanks.

2. Sludge is not compacted; occupies a lot of space.

3. CHP does not operate.

4. Methane is emitted in the atmosphere.

Introducing the concept of "zoning" *

Repair of methane tanks

Sludge to be utilized both at the WWTP site and subsidiary facilities (compost)

At the CHP to lay in a fuel stock.

Methane surplus to be burnt as a “fire”.

Accident at the CHP

How to use methane generated in methane tanks?

Where to get heat for sludge heating during digestion?

To repair CHP.

To burn biogas as a “fire” or to purchase equipment for methane burning.

Breakage of wastewater treatment facility

Pollution of the Don river aquatic ecosystems

To transfer flow of wastewater to another treatment line.

Disastrous flood with water flooding high floodplain terrace

Pollution of the Lower Don river aquatic and terrestrial ecosystems

Diking the WWTP territory in case of disastrous flood forecast

Act of terrorism (effluents poisoning, androlepsy of the WWTP workers)

Ecocatastrophe in the Lower Don basin

To prevent terrorists penetration at the WWTP site; to strengthen protection of a waste ditch.

* According to the concept of "zoning" in areas where explosive mixtures may be present special precautions should be taken within these areas. This will include locating equipment which may cause sparks outside the danger zone, and careful choice of mechanical and electrical plant, pipelines etc. within the zone.

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Chapter 11 Uncertainties 1. No direct measurements of air pollution at the WWTP site and within sanitary-protection zone. This precludes assessment of reliability of estimates on emissions methane and toxic substances. 2. Due to complex intrareservoir hydrochemical and hydrobiology processes it is impossible to assess impact of nutrient reduction on hydrobionts growth, on intensity of reduction processes and inflow of pollutants from the bottom sediments, on development of pathogenic organisms in the Din river downstream the WWTP discharges. 3. Surveys of ground water regime are occasional. Thus, materials on their pollution are non-systematic. Their volume is insufficient for proper conclusions. Chemical composition of sludge (primary, secondary, active) is insufficiently studied. There is no data on seasonal dynamics of sludge generation and chemical composition. Proposals on sludge processing and utilisation are not finally formulated. It is necessary to determine content of aluminium (gross, in water and acetate-ammonium extract) in sludge under different methods of wastewater treatment (without phosphorous chemical stripping and with use of alums) and to verify compliance of sludge with normative documents:

GOST P 17.4.3.07.-2001 “Nature protection. Soil. Requirements to sludge if used as fertilisers”;

SanPiN 2.1.7.573-96 “Hygienic requirements to use of wastewater and sludge for irrigation and as fertilisers”;

SP 2.1.7.1038-01 “Hygienic requirements to organisation and maintenance of the MSW landfills”.

Content of organic matter in sludge varies: in terms of dry matter – 45-47%; total nitrogen – 3.2–2.5%; phosphorous in terms of Р2О5 – 3.5–3.4%; lead – 45-48 μg/kg, cadmium – 5.8-9.4 μg/kg; copper – 123-124 μg/kg; nickel – 62.6-71.6 μg/kg; zinc – 800-832 μg/kg; chromium - 352-375 μg/kg; manganese – 104-109 μg/kg; mercury 0.1-0.5 μg/kg; arsenic – 7.8-9.3 μg/kg. Concentration of heavy metals will nor exceed MAC for soil if compost is produced from this sludge with addition of glauconitic sand, bentonite and other fillers.

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Chapter 12 Justification of selected option of the planned WWTP reconstruction Thus, analysis of environmental conditions and technical feasibility of the WWTP reconstruction in order to achieve waste water quality objectives shown that option of the WWTP reconstruction providing biological treatment, advanced treatment of waste water and phosphorus chemical removal with sludge compaction in methane tanks (digestion), collection and utilisation of methane on designed CHP plant is the most preferable in terms of key environmental parameters:

Sludge volume will be reduced by sludge digestion and compaction. This will ease problem of sludge temporary storage at site.

Reduction of moisture of sludge that will be stored at drying beds will significantly reduce danger of ground water pollution in case of sludge water filtering.

Burning of biogas at own CHP plant will not only reduce methane emissions but will also reduce total amount of greenhouse gases both at the WWTP site and generating power at power plants.

Higher level of treatment of wastewater discharged into the Don river will be achieved after the WWTP reconstruction. Content of pollutants will comply with stated requirements of maximum permissible discharges and existing regulatory documents. This will improve the Don river water quality and reduce the eutrophication of both the lower river reaches and the Taganrog Bay.

Phosphorus compounds are extremely dangerous for water ecosystems. They are limiting factor for development of many organisms (including green-blue algae contributing in water blossoming). Risk of eutrophication will be significantly reduced by additional treatment of wastewater from phosphorus compounds with chemical reagents.

Reliable and well-documented process technology is advantage of the present option. Management means are simple, i.e. it is easy to support high efficiency of phosphate removal through control of reagents’ doses.

More complicated technology of wastewater treatment and additional costs on chemical phosphorus stripping are method disadvantages. Wastewater will be coloured if iron salts will be used as reagents. It will be difficult tidewater this sludge (traditional MSW without metal salts are easy to dewater). Tertiary filtration will be required to remove phosphorous in suspended solids.

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Chapter 13 Public hearings on EIA and activities on environmental education and public awareness Environmental education and public awareness, discussion of the EIA materials were part of the activities through the whole period of work under the present Contract. The following activities were part of this task: Publication of materials in mass media

The following articles were published based on materials prepared as part of the environmental impact assessment:

• Methane power plant for Vodokanal. Newspaper “Gorod N”, 28 February 2004. Author E. Petrova.

• On the way to pure water. Bulletin of the Ministry of Construction, Architecture, and Housing and Communal Services of the Rostov Oblast, No. 2 (6), 2004. Author Ya. Volgar.

Public hearings were organised in Rostov (Annexes 1-2). Brochure and leaflets with results of the EIA of the Rostov Vodokanal WWTP

reconstruction, as well as possibility to replace phosphorous-containing detergents with other types of detergents free of phosphorous were prepared and disseminated in cities Rostov, Azov, settlement Koluzaevo.

Draft ToR on Project results dissemination was developed (see Chapter 15).

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Chapter 14 Environmental Management Plan The preliminary review of the Project components conducted within preparation of the Concept in 2001 – 2002 shown that the Project would have minor adverse environmental impact. Based on that Project was given Category B. However, in order to reduce negative environmental impact at local level the Environmental Management Plan was prepared. This Plan will be subsequently improved, added and approved within PDF-B documents development according to procedures applicable for the Russian Federation and the World Bank. The objective of the Environmental Management Plan (EMP) is to ensure that the adverse impacts are mitigated as far as possible, taking into account complementary institutional strengthening and social aspects. It also recommends ways of mitigation and monitoring. The EMP therefore contains:

Environmental Mitigation Plan to address the adverse environmental impacts; Environmental Monitoring plan to record environmental impacts of the Project

and to take corrective action when necessary; Recommendations for training and capacity building; and Social aspects of project implementation.

14.1 Mitigation Plan Mitigation Plan objective is to minimise negative environmental impacts of the Project. Recommended mitigation measures are presented in a form of a plan (Table 14.1). Plan’s objective is to present the list of potential mitigation tasks and suggest delegation of responsibilities for their implementation. Agencies which may have responsibilities for control and monitoring include the Oblast Environmental Committee, Ministry of Natural Resources (local agencies), City Department of Construction, Rostov Oblast Centre for Sanitary Supervision, Gosgortechnadzor, Ministry of Emergency Situations. Their responsibilities are specified by the current legislation of the Russian Federation. Training requirements are summarised in the last part of the present Plan. It is not envisaged that the mitigation measures (apart from the required training) will incur significant extra costs. The proposed Plan includes the following components for construction and rehabilitation: Component 1: Upgrading of screening and grit removal

Component 2: Renovation of the primary settlement tanks

Component 3: Modification and extension of the secondary aeration tanks

Component 4: Incorporation of lamella settlers

Component 5: Chemical Phosphorus stripping

Component 6: Sludge digestion

Component 7, 8: Combined Heat and Power (CHP) Plant – Methane use

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Table 14.1 Mitigation Plan Construction

No. Component*

Parameter Impact Mitigation Measure Responsibility

1 All Air quality; Surface water quality

Minor negative impact due to spillage, (oil, diesel etc), careless waste disposal or operation of machinery

Careful site supervision and working practices as specified in construction norms (SNiPs), spill control procedures, correct choice of fuel and plant maintenance.

Contractor**, with site supervision from RVK and other bodies as necessary

2 1-4, 7 Air quality on technological lines and at sites of sludge storage lagoons and sludge drying beds

Existing negative impact on air composition, odour nuisance

Registration of the existing pollution level before completion of construction and reconstruction works.

RVK, Centre for Sanitary and Epidemiologic Supervision

3 All Solid waste disposal

Minor negative impact from the works due to large quantities of waste construction materials produced

Compliance with standard procedures (city ordinances) for construction waste disposal. The construction supervisor should ensure best practice, through re-use of construction materials and the removal of hazardous wastes for separate disposal.

Contractor**, City Department of Construction, with site supervision from RVK and other bodies as necessary

4 All Solid waste disposal

Minor negative impact from the works due to large quantities of the yield and conveyed soil

Compliance with standard procedures (city ordinances) for soil disposal

Contractor**, City Department of Construction, with site supervision from RVK and other bodies as necessary

Note: * Description of components see above; **- All contracts within the project have to include an item with requirement that all activities to be implemented in compliance with the existing regulating documents (SNiPs) and rules on mitigation of adverse impact of noise, dust and transport (including emergency signs, etc.). In their Contracts should comment on ways to reduce this adverse impact.

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Table 14.2 Mitigation Plan Operation

No. Component*

Parameter Impact Mitigation Measure Requirements to monitoring: measured

parameters and methods

Responsibility

1 5 Surface water quality

Pollution of surface water due to overdosing of chemicals for phosphate stripping

Ensure that chemical dosing is carefully controlled through development of a sampling regime and regular sampling of effluent and sludge after lamella separators and of sludge in Phosphorus settling tank to ensure correct dosing level

Standard parameters of water quality. Standard laboratory methods – wastewater delivered for treatment and treated wastewater plus selected positions within the process (see Chapter 3, Table 1).

RVK/ Ministry of Natural Resources (local bodies)

2 6, 7, 8 Air quality Use of natural gas to fire boiler to supply energy to sludge digesters and centrifuges. Magnitude of impact depends on design of digesters chosen

Use excess heat from CHP plant cooling waters whenever possible

Periodic control of gas equipment.

RVK / Gosgortechnadzor

3 6, 7, 8 Energy consumption

Significantly increased energy requirements for sludge digestion and sludge dewatering processes

This impact is difficult to mitigate, as it is an unavoidable result of process changes designed at improving other environmental receptors (especially air quality). The impact can be mitigated to some extent through monitoring to ensure that the processes are operating at optimum efficiency, thus minimising energy consumption

Monitoring of gas consumption and gas composition. Periodic control of energy efficiency.

RVK

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No. Compon

ent* Parameter Impact Mitigation Measure Requirements to

monitoring: measured parameters and methods

Responsibility

4 6, 7, 8 Sludge quality

Ground pollution at storage sites

Storage in a special sites, use and disposal taking into account requirements for hazardous waste handling stated in the RF Government Decree No. 340, 2002 (it is required to develop special programme for the WWTP sludge use and disposal).

Analysis of dried sludge. Levels of moisture content, density, chemical composition, pathogens

RVK, Centre for Sanitary and Epidemiologic Supervision

5 6 Health and safety

Potential health and safety risk associated with the presence of an explosive air/gas mixture in the vicinity of the sludge digesters

Areas where explosive mixtures may be present should be identified, and special precautions taken within these areas. This will include locating equipment which may cause sparks outside the danger zone, and careful choice of mechanical and electrical plant, pipelines etc. within the zone.

Periodic agencies and state monitoring of compliance with standards of fire and flame safety.

RVK/ Gosgortechnadzor / Ministry of Emergency Situations

Note: * Description of components see above; **- All contracts within the project have to include an item with requirement that all activities to be implemented in compliance with the existing regulating documents (SNiPs) and rules on mitigation of adverse impact of noise, dust and transport (including emergency signs, etc.). In the proposals Contractors should comment on ways to reduce this adverse impact.

14.2 Monitoring Plan Plan’s objective is to ensure that monitoring is conducted in order to:

Provide sufficient information so that the success of the project can be measured in terms of meeting nutrient and methane reduction objectives;

Identify inefficiencies and failure to meet the targets, allowing process changes to be made to improve problems;

Enable any negative impacts of the process changes to be identified so that process changes may be made where possible;

Demonstrate the successes/failures of the project to allow replication, with changes as required, in other WWTW around Russia; and

Provide improved data on the environmental impact of the Rostov WWTP. It is important to collect and analyse data on a regular basis in order to detect necessity for process changes or improvements, or when failures have occurred. There are training requirements related to the recommended monitoring requirements. Both monitoring and training will incur additional project costs. Monitoring during Construction If recommended site practice and supervision is followed, reasonable monitoring will be required during construction. It may be appropriate to nominate a Construction Supervisor to ensure that required environmental and health and safety procedures are met during construction. Groundwater monitoring would only be required if problem was identified during construction of a new building, tank or underground pipeline. Background measurements of air quality will be organised at the WWTP site and within sludge drying beds and sludge storage lagoons. They will form a “reference point” for future operation. Monitoring during Operation To facilitate operation of a new, more complicated process the WWTP laboratory’s monitoring programme has to be expanded. An expansion to the existing regime is given in details in Table 14.3 below. Sampling of phosphorus at the reagent dosing phase is important to ensure correct dosing. It is recommended to sample at least three times a day. Table 14.3 Proposed Expansion to Sampling Regime within the works

New monitoring parameters Location Frequency Total phosphorus Inlet/Outlet 1/dayTotal phosphorus Phosphate stripping

reagent dosing point At least 3/day

Soluble orthophosphate Inlet/Outlet 1/dayVolatile Fatty Acids Inlet to aeration tanks 1/weekAlkalinity Inlet to aeration tanks 1/daySuspended solids concentration Aeration tanks 1/dayTotal iron Outlet 1/daypH Aeration tanks 1/dayDissolved oxygen Aeration tanks (each zone) 1/day

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Nitrate Outlet 1/dayAmmonia nitrogen Outlet 1/day

It is proposed to develop and implement special monitoring and control programme for gas equipment and protocol on sampling and air quality monitoring programme. 14.3 Training and Capacity Building Requirements After completion success of the new process will depend on staff operational skills, including:

Understanding of new process and all components; Training in operational requirements; Planned maintenance; Safe working conditions, e.g. zoning, chemical usage; Process monitoring; Laboratory upgrading; Computer (IT) equipment; and Training and permission to work with hazardous substances.

Existing sampling equipment and laboratory facilities are insufficient to achieve recommended objectives. Laboratory services should be expanded to provide information required for optimum operation of a new system. This would include:

Routine chemical tests; Laboratory scale digesters; Routine efficiency calculations; Gas volume and composition measurements; and Instrumental monitoring.

Overall project budget allocates funds for operation and maintenance of the WWTP. It is recommended that costs for the above-mentioned activities should be included in project budget to ensure successful operation of new equipment and processes. Projects aimed at upgrade of the RVK’s laboratories are also considered in the RVK Strategic Plan. 14.4 Social aspects of project implementation Detailed description of social impacts as part of the project implementation will be available after special social study planned as part of the PDF-B grant activities. However, it is possible to say that component 1-8 will have minor social impact; it is expected that impacts will be positive as water quality will improve, and emissions of greenhouse gases will decrease due to rational use of electric and thermal energy. Thus, the project has no special activities dealing with social impacts. All construction and reconstruction activities should be done in compliance with the existing local and Russian standards in the sphere of construction and environmental protection. In the proposals Contractors should comment on ways to reduce adverse impact or compensate temporary inconveniences due to construction works.

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Chapter 15 Dissemination Programme For dissemination of experience gained as part of the Project on Reduction of Nutrient Discharges and Methane Emissions in Rostov-on-Don implementation in Russia and abroad the following activities were proposed:

To popularise and disseminate information about Project’s outputs Preparation and publication of the brochure with description of key Project

outputs. Preparation and dissemination of a multimedia film on a CD. Mobile exhibition or participation in environmental exhibitions in the coastal cities

and towns. Environmental actions on information and results dissemination in the cities and

towns of the Azov-Black sea basin (for example, the Black Sea Day). Meetings with representatives of Administrations and Vodokanals in coastal cities

and towns. Training and raising the level of specialist’s skills

Training workshops for decision makers. Preparation of a training course and raising the level of specialist’s skills.

Public campaign in mass media International workshop for journalists. Publications of materials on Project results and achievements in local mass

media. To develop draft Terms of Reference on technical assistance in experience dissemination.

Key objectives of the ToR: To promote dissemination of project decisions on reconstruction of the Rostov

WWTP aimed at improvement of the Don River and Azov sea water quality and rehabilitation of region environment by means of eutrophication reduction and decrease of pollution from municipal sources.

To learn lessons from the Rostov project and to identify most successful innovations for their further dissemination in other regions of the Azov-Black sea basin and the Danube river basin.

To promote dissemination of the Action Plan on Environment protection within the Azov-Black sea basin.

Objectives of the current task will be achieved through implementation of the following interrelated tasks: Task 1. To improve infrastructure

To develop, test and publish training modules on integrated wastewater treatment. To support training workshops on environmental policy for staff involved in waste

water treatment: municipalities, municipal and Oblast inspections, environmental agencies and private sector.

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At the final stage to organize and co-ordinate in Rostov International conference on waste water treatment issues in order to disseminate information in other regions of the Azov-Black sea basin.

Task 2. To transfer technology (skills). To promote dissemination of the most appropriate technology of wastewater

secondary treatment and advanced treatment at the WWTP. To promote dissemination of the most suitable technology for the WWTP sludge

utilization. To promote organization of constantly working classes on training and technology

transfer. To promote communication and partnerships between towns and cities of the region

in respect to integrated wastewater treatment. Task 3. To inform general public, to improve public awareness and environmental education.

To promote campaigns in mass media in order to organize public debates and dialogues on wastewater treatment (regional press and electronic mass media). International workshop for journalists is proposed in addition to traditional means of communication with mass media.

To promote assistance in development of a training course on environment protection (official, unofficial, popular), including water quality, health protection, sanitary and environmental protection.

In co-operation with the PIU to develop guidelines on best available practice to reduce nutrient discharges and methane emissions, including publications of brochures, booklets, multimedia films on CDs.

In co-operation with the PIU to promote organization of training workshops, working meetings and consultations for staff of the WWTP, environmental agencies and decision makers.

To provide technical expertise to initiatives of the Oblast authorities in rehabilitation of the Don river natural ecosystems.

Towns and cities for results dissemination: in Russia – Azov, Taganrog, Novorossiisk, Sochi; in Ukraine – Mariupol, Nikolaev, Sevastopol, Odessa; in Georgia – Batumi, Sukhumi; in Bulgaria – Varna, Burgas; in Romania – Konstansa; in Turkey – Samsun.

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Key conclusions Project on reconstruction of the Rostov WWTP is presented in a Feasibility Study: reconstruction of the Rostov WWTP (Phases I and II) (2000), in reports prepared by "JACOB-GIBB" (2003) and "SWECO INTERNATIONAL" (2004). The EIA is based on these reports. Biological treatment and advanced treatment of waste water, removal of phosphate compounds with chemical reagents, digestion of waste water sludge in methane tanks to reduce greenhouse gases emissions, and use of the produced methane as fuel for a combined heat and power (CHP) plant was proposed by the "SWECO INTERNATIONAL" as a principal option for waste water treatment. The WWTP reconstruction is designed stage-by-stage due to lack of funding. At the preliminary phase WWTP capacity will be 360,000 m3/day. For a long-term period total WWTP capacity is designed as 460,000 m3/day of wastewater. This flow divides in 50% per two phases. Prospective peak flow for each phase is about 13,300 m3/hour. New construction or reconstruction of the following elements is envisaged in accordance with the required treatment plant capacity, treatment level and method based on SWECO's recommendations and according to the approved feasibility study. Phase I works: 1. Screen building (reconstruction with installation of "thin" screenings). 2. Grit traps will be site for addition of liquid alum (reagent for phosphate

compounds settling); thus, pre-aeration chambers will be used for preliminary sedimentation;

3. Aeration tanks (reconstruction with identification of anoxic zone – denitrificator and aeration zone - nitrificator).

Phase II works: 1. Screen building (reconstruction). 2. Pre-aeration tanks - primary settlement tanks (reconstruction: existing sludge

scrapers will be replaced by new scrapers; concrete constructions will be repaired; sludge pumps will be replaced by stainless steel pumps);

3. Aeration tanks (reconstruction with identification of anoxic zone denitrification and aeration zone - nitrificator).

4. Secondary horizontal settlement tanks (three lines out of four will be completed with lamella modules and brush filters - bioreactors with immobilized micro flora well proven on Phase 1);

Facilities for wastewater advanced treatment (II stage) of Phases I and II 1. Reception (inlet) chamber (reconstruction). 2. Entry chamber (designed). 3. Filters for advanced treatment (reconstruction). 4. Pumping station for advanced treatment filters (reconstruction). 5. Reservoir for washing water (reconstruction). 6. Filters media storage facility (reconstruction).

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7. Aerator trough (aeration tank) (reconstruction, designed).

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Facilities for sludge processing, Phases I and II 1. Gravel bunkers (extension). 2. Sludge compactors D=18 m (reconstruction); 3. Methane tanks (re-equipping up to 5,000 m3). 4. Two reservoirs will be constructed for gas storage 3,000 m3 each and new

reservoir for digested sludge storage (capacity 2,000 m3); power generation plant; building for heat exchangers; gasholders; methane tanks pumping station;

5. Site for mixing wastewater with humin-mineral concentrate, and storage facility; Supporting buildings and facilities 1. Blowing house and pumping stations No. 1 and 2, pumping station in passes of

capacity blocks of Phase II, pumping station of sludge compactors (reconstruction), in-site communications will be reconstructed;

2. Reagent storage building with storage facility (two new plants will be constructed for alum reception, storage and processing, one plant will serve line 1 or 2 phases).

The WWTP improvement in terms of nutrients removal will provide significant improvement of effluents quality and will allow necessary reduction of phosphorous concentration by 60% and total nitrogen concentration by 50%. "SWECO INTERNATIONAL" recommended that final objectives for treated wastewater of the Rostov WWTP should comply with SNiP norms. The following parameters will be used for treated effluents at the intermediate phase of the Rostov WWTP reconstruction (Table 1). Table. Approved standards for treated wastewater of the Rostov WWTP

Pollutants in treated wastewater Pollutants Intermediate Full reconstruction

Organic matter (in terms of BOD5) < 15 mg / l < 3 mg / lSuspended solids < 25 mg / l < 3 mg / lAmmonia nitrogen < 0.39 mg / l < 0.39 mg / lNitrite nitrogen 0.02 mg / l 0.02 mg / lNitrate nitrogen 2.5 mg / l 2.5 mg / lTotal nitrogen < 3 mg / l < 3 mg / lPhosphates (P2O5) < 1.95 mg / l < 0.61 mg / lPhosphorous (estimated in P2O5-P) < 0.65 mg / l < 0.2 mg / l

According to "SWECO INTERNATIONAL" estimates after reconstruction effectiveness of the POC (potential of oxygen consumption) will increase from about 67% to 93%. Further investments in effective operation of an additional treatment phase will increase effectiveness by 3%. Selected strategy of stage-by-stage reconstruction can be regarded as a highly successful solution. Various environmental impacts will be registered both during reconstruction and operation phases due to emission of pollutants, effluent discharges into the Don river, formation and location of production and consumption wastes and other impacts. The

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following three alternative options were selected for environmental impact assessment: Zero option: the existing situation will remain at the WWTP, no reconstruction

works. Option with biological treatment, advanced wastewater treatment and chemical

removal of phosphorous. Option with reduction of nutrients using only biological treatment of wastewater.

Undertaken assessment and environment state forecast provided evaluation of the WWTP reconstruction options: 1. Rostov-on-Don emissions define atmospheric pollution in the Don river left bank floodplain. Level of atmospheric pollution in the area of WWTP is minor. Only nitric oxide and carbon concentrations are recorded at MAC levels. Concentrations of other gases are all lower than MAC values. Concentrations of some heavy metals are increased in solid-phase atmospheric fall-outs. At WWTP site recorded emissions are 5.68 tons of methane per year (sludge drying beds and sludge storage lagoons) and 3.076 tons of carbon oxide per year (boiler-room) (according to data provided by the Central Board on Natural Resources and Environment Protection of the Rostov Oblast, RF Ministry for Natural Resources). For other pollutants input of the WWTP into atmospheric pollution in the area of Zarechnaya industrial zone is very low compared to other industrial enterprises located here. If project on the WWTP reconstruction with installation of a plant for methane collection and utilisation to be implemented then emissions of this gas will reduce from 14 to 4 kg/day (by 3.5 times). "JACOB-GIBB" assessed present emissions of WWTP gases causing green house effect taking into account gases from used electric power and coal burning at local heat station. Data was compared with estimates of emissions after the WWTP reconstruction (taking into account use of mesophilic methane tanks and heat station operating on biogas produced). According to the estimates total mass of emissions in terms of CO2 under “zero” option will be 519.914 kg/day = 189.769 tons/year for the year 2006 and 688.893 kg/day = 251.446 tons/year for a long-term period. In case of sludge anaerobic digestion and construction of CHP plant (without preliminary sedimentation) total mass of emissions in terms of CO2 will be 377.314 kg/day = 137.720 tons/year. In case of chemical removal of phosphorous and anaerobic digestion total mass of green house emissions in terms of CO2 can increase up to 452.777 kg/day = 165.264 tons/year in a long-term forecast. 2. Content of copper, iron (in summer), phenols (in summer), organic matter (BOD5), sulphates and nitrites (in winter) exceeds MAC values in the Don river water at the reach between the Tsimlyansk reservoir and river mouth. In the Don river mouth pollution increases in all seasons for sulphates (and water mineralization) and oil products; in winter - for nitrites, BOD5, iron. River reaches near towns of Aksai, Rostov, and Azov are the most polluted parts (in terms of BOD5, oil products – for all seasons, nitrites - in winter, phenols - in summer). Increase of anthropogenic euthrophication is periodically recorded at the mouth reach of the Don River. Maximum values of phytoplankton population are recorded in summer and autumn. At this time significant changes of community structure are registered due

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to modification of specific composition of dominant complex and tendency of certain species for a leading place. Hygienic standards for BOD5 (1.5 – 2 MAC), COD (1.5 – 3.5 MAC), total hardness (1.2 – 1.5 MAC), total iron (1.3 – 5.1 MAC) and oil products (1.2-32 MAC) (data provided by Centres of GosSanepidnadzor for Rostov-on-Don, Azov, Taganrog, Azov district) are recorded in the Don river water at water intakes and in recreation zones of populated areas. In terms of bacteriological pollution the Don river is regarded as a source with an increased level of epidemiological danger. Coli-fags, spores of sulphitreducing clostridia, choleroid micro flora were identified in river water. High level of river water bacteriological pollution is recorded in the Don river mouth area, especially downstream of Rostov sewage discharges and at the confluence of the Temernik and Don. Azov city water intake has the most critical situation with water quality in terms of microbiological pollution. This is due to discharge of insufficiently treated and crude wastewater of Rostov city in the Don river. Use of drinking water with bacteriological and viral pollution leads to acute enteric infections and viral hepatitis type A. Conditions of the WWTP wastewater discharges into the Don River are stated by requirements of the “Rules of surface water protection from pollution” for a water body of category 1 of fisheries importance. Reconstruction of the Rostov WWTP by option with biological treatment, advanced wastewater treatment and chemical removal of phosphorous will provide high level of wastewater treatment. In this case content of pollutants will comply with stated maximum permissible discharges and existing regulatory documents. After reconstruction using this option the WWTP input in water pollution in terms of nitrite nitrogen, ammonia nitrogen and organic matter will reduce from 23%, 6% and 7%, respectively, up to a zero. Content of these substances in treated wastewater will be equal or less than content in riverine water. Input in terms of nitrate nitrogen and phosphorous will reduce by a factor of two, i.e. from 14% to 7%. However, after a deep treatment estimated concentrations of nutrients in ambient water downstream effluent discharge place will reduce insignificantly: for nitrite nitrogen - from 0.32 to 0.26 mg/l and for phosphorous - from 0.16 to 0.15 mg/l. In case of the WWTP partial reconstruction (intermediate option with waste water volume of 360,000 m3/day) the WWTP input in the Don River water pollution in terms of nitrite nitrogen and ammonia nitrogen can be reduced from 23% and 6%, respectively, up to a zero. Content of these substances in treated wastewater will be equal or less than content in riverine water. Input in terms of organic matter will reduce from 1.7% to 1.5%; in terms of nitrate nitrogen will reduce by 3.5 times (from 14% to 4%), and for phosphorous will remain invariable. After treatment estimated concentrations of nutrients and organic matter in ambient water downstream effluent discharge place will reduce insignificantly: for nitrite nitrogen - from 0.032 to 0.026 mg/l, for nitrate nitrogen – from 0.32 to 0.29 mg/l, and for organic matter - from 4.08 to 4.06 mg/l. Disadvantage of biological treatment without preliminary chemical sedimentation of phosphate compounds is low level of wastewater treatment preventing achievement of maximum permissible discharges values and meeting existing requirements to effluents discharged into category 1 water bodies used for fishery and household/drinking purposes. Effective disinfection of treated wastewater will reduce the Don river bacteriological pollution. However, in order to improve water quality downstream Rostov in terms of microbiological parameters it is necessary to discontinue discharges of crude (untreated)

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wastewater into the Temernik and Don rivers, and to construct storm water sewer. Indicated activities will significantly reduce microbiological water pollution at water intakes located downstream Rostov; discontinue use of drinking water hyperchlorination in Azov and Azov district; reduce sickness rate of enteric infection of bacteriological/viral nature, and allow wider use of the Lower Don as a recreational zone. 3. Chemical composition of ground water forms due to atmospheric precipitation, infiltration of technogenic water at the WWTP site, as well as pollutants washing from unauthorised dump of household and industrial wastes located in the northern part of the WWTP. Organic substances (high value of BOD5), oil products (8-58 MAC), iron and cadmium (0.035 – 0.077 mg/l) are the most typical elements of ground water pollution. During the WWTP reconstruction it is planned to reduce volume of sludge stored at sludge drying beds and sludge storage lagoons. Less sludge and storm water enriched with organic and other pollutants will be filtered into ground water. This will contribute to reduction of ground water pollution. 4. According to lithochemical survey in the area of the WWTP level of soil pollution with heavy metals is minor. Contrast and vast lithochemical anomalies were not discovered. Planned reconstruction of the WWTP will not contribute to increase of soil and underlying surface pollution, as well as technogenic flows contacting with soils will have less pollutants. All reconstruction and construction activities will be held within the WWTP limits. Thus, use of new lands for construction is not planned. 5. Involvement of new sites into operation is not planned, so, during construction works adjacent natural landscapes will not degrade. After the WWTP reconstruction reduction of agrochemical and hydrochemical load on neighbouring landscapes with decrease of atmospheric emissions and reduction of filtering sludge water will be beneficial for growth of floodplain ecosystems’ vegetation cover and fauna. 6. In the zone of the Rostov industrial centre natural oxygen and oxy-gley landscapes in the Don River were transformed into oxy-hydrosulfuric under technogenesis. Increase of pollutants concentration in all landscape components, increased accumulation of organic matter at the bottom, intensification of reduction processes, their shift from sediments to near-bottom waters, flow of dissolved elements (compounds of nitrogen, phosphorous, microelements) from silts to water column will accompany this transformation. Weakening of technogenic pressure on the Don river will be recorded after WWTP reconstruction. Decrease in discharge of organic substances and nutrients will result in reduction of river eutrophication and decrease of reduction processes intensity. Oxidised layer preventing entry of pollutants from bottom into water column will remain longer on bottom sediments surface. 7. At present total amount of produced sludge consists of 1220 m3/day primary sludge and 1355 m3/day surplus activated sludge. Sludge (mechanically dewatered or dried at drying beds and kept in natural conditions for not less than 2 years) has a moisture content of 54-58% respectively and is regarded as waste of class IV danger. If existing situation remains then impact of production and consumer waste on environment will be gradually increasing due to limited place for the WWTP waste disposal and their accumulation at site. Option providing reduction of nutrients only with biological treatment includes various construction activities: reconstruction of secondary settlement tanks, installation of lamella settlers, construction of sludge digesters and construction of CHP plant. This will result in a short-term local impact of large masses of soil on soil cover at the WWTP site

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and in a possible minor impact on ground water. Impact will stop after completion of building and assembly works, after construction of tank support walls from extracted soil, and covering area. Quantity of screenings will increase with operation of reconstructed WWTP. Their impact will not increase due to potential disposal to the Rostov landfill site. Sludge volume will increase after full biological treatment of wastewater. Then all produced sludge will pass through a closed cycle to the sludge digesters, which will minimise the amount of sludge produced. This in combination with reduction of nitrogen, phosphorous, BOD determines potential decrease of sludge negative impact on air, soil, surface and ground water compared to the “zero” option, mainly due to a decrease of greenhouse gases emissions. Volume of primary sludge increases in case of chemical removal of phosphorous. But due to later sludge digestion and dewatering total volume of sludge compared to the existing situation either will remain the same or will increase insignificantly without growth of anthropogenic load on environment but limiting possibilities of sludge use. It will be possible to reduce load on air and ground water due to qualitatively new parameters of produced sludge and gradual processing of earlier accumulated sludge from the existing sludge storage lagoons. 8. There will be no significant impact during construction on climate; hydrology; terrestrial or aquatic ecology; water resources, supply and sanitation; public health (apart from occupational health, discussed below); land use, industry and agriculture; fisheries; energy consumption; transport infrastructure; tourism and recreation; cultural heritage; groundwater quality; or sediment quality. The construction of new buildings and tanks will have a slight impact on topography, but this is not considered to be significant in the context of an industrial complex. All construction work will have a slight positive impact on ‘population, employment and income’ through employment generation. Construction works may have minor negative impacts on surface water and air quality through operation of cars, machinery (atmospheric emissions, spillage of petroleum products, etc.). Impacts can be mitigated by correct choice of fuel and proper machinery operation, use of spill control procedures, enhanced control on polluted soil collection and utilisation. The construction of buildings, tanks and underground pipelines may have an impact on the groundwater regime. This impact may be assumed to be negative (in disruption of existing groundwater flows) but the level of impact is likely to be marginal and no mitigation measures would be required. However borehole monitoring should be instituted where there is likely to be groundwater diversion or rising water tables There may be a slight decrease in effluent quality during works which require direct interruption of process lines, but this is likely to be insignificant because retention time would not decrease significantly as the works currently has excess capacity. All works generate construction waste. It is understood that soils excavated during building and tank construction will be used on site. Apart from soils, it is envisaged that the waste generated will be relatively small and therefore have only a slight impact on waste disposal. This impact should be mitigated by compliance with existing requirements (RF and Rostov Oblast ordinances) for collection, temporary storage and final disposal of construction waste. Special activities for waste recycling should be

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developed and implemented where possible. 9. There will be no impacts during operation on topography, geology and soils; hydrology; water resources, supply and sanitation; and cultural heritage. At this stage, it is envisaged that there will be no significant impact on ‘population, employment and income’ as there will be no major changes in staff needs. Given that this project is grant-funded, it is considered unlikely that it will have a negative impact on the population in terms of ability to pay for services. In a long-term period there are no impacts on land use, industry, agriculture, but some positive impacts can originate due to disposal of less amount of biologically less activated sludge. The new buildings, pipelines and tank are likely to have a minor impact on hydrogeology due to flow diversion. The reduction of nitrogen levels with the reduction in phosphorus levels in effluents is likely to decrease the eutrophication of the river, thus having a positive impact on aquatic ecology and fisheries. Reduced levels of eutrophication will have a positive impact on river water quality, decrease of oxygen deficit and toxin release events. This will have a beneficial impact on aquatic ecology; public health, fisheries; tourism and recreation. Given the large phosphorus reservoir in the riverine sediments, positive impacts on sediment quality will accrue over time. In the short term, therefore, there will be no positive impact on sediment quality. Sludge digestion will ensure major environmental improvements as the process leads to a significant reduction in sludge volume, and allows for the capture of methane for beneficial use. Digestion converts the volatile organic fraction of the sludge into a mixture of methane and carbon dioxide. There will be other benefits in addition to reduction of methane emissions form the WWTP site, such as:

During thermal digestion there will be a significant decrease of pathogens (salmonella and streptococcus) in sludge. This will make sludge more suitable for recycling.

Anaerobic digestion will provide longer storage of dewatered sludge at site, as sludge volume will reduce from 35,000 to 30,000 m3 per year. Decrease in sludge amount will result in cost savings on polymers (for dewatering) and transportation of sludge to a disposal site.

Use of energy from methane burning for energy supply to the WWTP, as well as for buildings heating and digested sludge warming will provide energy savings and reduction of operational costs.

Reduction of sludge volume in sludge storage lagoons is likely to have a positive impact on groundwater quality (less filtration of polluted sludge water) and air quality (less emission of methane, mercaptan, other pollutants). The operation of digesters represents a potential risk due to the presence of areas where explosive gas/air mixtures can be present. It will therefore be vital to introduce the concept of "zoning". Areas where explosive mixtures may be present should be identified, and special precautions taken within these areas. This will include locating equipment which may cause sparks outside the danger zone, and careful choice of mechanical and electrical plant, pipelines etc. within the zone.

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10. For the studied area environmental limitations are compliance to norms of maximum permissible emissions taking into account inputs in background pollution; maximum permissible discharges in compliance with conditions of their diversion into the Don River as water body of the 1 category in terms of fisheries and household-drinking purposes, as well as limited disposal of waste in compliance with existing permissions. Special restrictions are absent: the WWTP locates outside water protection zone of the Don River, nearest populated settlement is situated outside sanitary – protection zone (100 m). Thus, analysis of environmental conditions and technical feasibility of the WWTP reconstruction in order to achieve waste water quality objectives shown that option of the WWTP reconstruction providing biological treatment, advanced treatment of waste water and phosphorus chemical removal with sludge compaction in methane tanks (digestion), collection and utilisation of methane on designed CHP plant is the most preferable in terms of key environmental parameters:

Higher level in treatment of wastewater discharged into the Don river will be achieved after the WWTP reconstruction. Content of pollutants will comply with stated requirements of maximum permissible discharges and existing regulatory documents. This will improve the Don river water quality and reduce the eutrophication of both the lower river reaches and the Taganrog Bay.

Phosphorus compounds are extremely dangerous for water ecosystems. They are limited factor for development of many organisms (including green-blue algae contributing in river water blossoming). Risk of eutrophication will be significantly reduced by additional treatment of wastewater from phosphorus compounds with chemical reagents.

Sludge volume will be reduced by sludge digestion and compaction. This will ease problem of sludge temporary storage at site. Reduction of moisture of sludge that will be stored at drying beds will significantly reduce danger of ground water pollution in case of sludge water filtering.

Burning of biogas at own CHP plant will not only reduce methane emissions but also will decrease total amount of greenhouse gases both at the WWTP site and generating power at the Novocherkassk power plant.

Reliable and well-documented process technology is advantage of the present option. Management means are simple, i.e. it is easy to support high efficiency of phosphate removal through control of reagents’ doses.

More complicated technology of wastewater treatment and additional costs on phosphate chemical removal are considered as method’s disadvantages.

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Annex 1 Minutes of the meeting of interested agencies and general public on Environment Management Plan

Grant for Preparation of the Project on Reduction of Nutrient Discharges and Methane Emissions in Rostov-on-Don

GEF Grant No. TF 027721 Minutes of the meeting of interested agencies and general public on Environment Management Plan

Rostov-on-Don, RRFSP office November 16, 2003

List of participants:

1. V Ostroukhova, Head of the Committee on Environment Protection and Natural Resources under Rostov Oblast Administration

2. V Garin, Head of the Rostov Regional Public Environmental Centre 3. N Bezuglov, Deputy Head of Construction Department, Rostov Municipality 4. V Aleshnikov, Deputy General Director of Rostov Vodokanal 5. V Lavrenov – Lead Specialist on Water Supply and Water Abstraction, RRFSP 6. V Khlobystov – Lead Specialist on Environment Protection, RRFSP 7. O Pankova, Press-secretary, Committee on Environment Protection and Natural

Resources under Rostov Oblast Administration Mr. V Lavrenov and Mr. V Khlobystov presented information on preparation of pre-feasibility study for Grant No. TF 027721. Environment Management Plan (EMP) was reviewed. Participants commented and made certain additions to the Plan. After exchange of views it has been decided:

1. To approve the Plan after making proposed changes and additions. 2. To recommend to Committee on Environment Protection and Natural Resources,

Vodokanal and Rostov Regional Public Environmental Centre to inform general public about the above mentioned Grant and developed EMP.

3. To submit to the World bank corrected and reviewed EMP. Minutes prepared by Mr. V. Khlobystov

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Annex 2 Protocol of the EIA public hearings

Rostov-on-Don, RRFSP office July 28, 2004 PRESENTED: A Kosogov Head of production and technical department, Municipal enterprise

“Construction Department”, Rostov-on-Don E Pochikaeva Chief medical officer, Rostov-on-Don Centre for State Sanitary and

Epidemiological Supervision T Rodionova Deputy chief medical officer, Rostov-on-Don Centre for State

Sanitary and Epidemiological Supervision O Khoroshev Deputy General Director, Rostov Regional Public Environmental

Fund A Orlinsky Lead Specialist, Rostov Regional Public Environmental Fund E Shustov General Director, CPPI-S A Ignatiev Deputy Head, Central Administrative Board on Natural Resources

for the Rostov Oblast, RF Ministry for Natural Resources V Nikanorov Head of department, Rostov Oblast Committee on Environment

Protection and Natural Resources N Tsapkova Director of Information centre, NPP “Don-INK”, CPPI-S consultant V Privalenko Doctor of Biology, Director of NPP “Environmental laboratory”,

CPPI-S consultant A Khovansky Head of the chair “Economic and Social Geography”, Professor,

geology-geographic department, Rostov State University, CPPI-S consultant

Yu. Bessmertny Manager of Habitat Division, Rostov Oblast Centre for State Sanitary and Epidemiological Supervision

S Karakulev Chief project engineer, FGUP North Caucasus Giprocommunvodokanal

S Panova Lead Specialist on Business Development, DV.kom A Kazaryants Deputy General Director, RRFSP V Khlobystov Lead Specialist on Environment Protection, RRFSP V Lavrenov Lead Specialist on Water Supply and Water Abstraction, RRFSP AGENDA To present and discuss results of the Environmental Impact Assessment undertaken by

the South Russian Centre for Preparation and Implementation of Technical Projects. Kazaryants: Mr. Kazaryants introduced himself and greeted participants. He expressed regrets that not many members of general public and funds came to public hearings, although a note was published in the local media in a proper time. He briefly described GEF project background. Funds were allocated for project preparation and work consisted of three parts: feasibility study of WWTP reconstruction, social assessment and environmental impact assessment (EIA). Feasibility study was conducted together with "SWECO INTERNATIONAL" (Sweden). Prepared social assessment was presented to Rostov Vodokanal for comments. South Russian Centre

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for Preparation and Implementation of Technical Projects (CPPI-S) won the EIA tender. Participants were informed about meeting’s objective: to conduct public hearings of the EIA, discussions and conclusion on undertaken work. He presented the EIA developers. Shustov: Mr. Shustov introduced himself and greeted participants. Briefly described CPPI-S, its key activities and working experience. Presented consultants involved in the EIA, namely: Prof. Khovansky, head of the chair, Rostov State University; Prof. Privalenko, Rostov State University; Mrs. Kosmenko, head of hydrobiological laboratory, Hydrochemical Institute; Mrs. Tsapkova, Director of Information centre, NPP “Don-INK”. Mr. Ulshtein and Mrs. Tarasenko (NPP “Don-INK” employees) were also involved in the EIA. They worked in co-operation and with assistance of Vodokanal specialists. The ToR has been agreed with the Committee on Environment Protection and Natural Resources under the Rostov Oblast Administration. Khlobystov. Clarified tasks and goals stated in the project ToR. He explained that three options were considered in the EIA: “zero”, intermediate and deep treatment. These were methods available by the time of the EIA presentation. Khovansky: Prof. Privalenko will present key outputs of the EIA. Privalenko mentioned that options were changing along with change of local objectives. There were some problems with understanding which option will be adopted as the final one. Number of options was clarified after 20 July 2004. In his presentation Prof. Privalenko covered the following issues:

1. Project objectives (long-term and short-term). 2. Main objective of the present work: the EIA of planned WWTP reconstruction for

three alternative options: “zero” (no reconstruction works); biological treatment, advanced treatment and chemical removal of phosphorous; reduction of nutrient concentration using only biological treatment of effluents.

3. Key parts of the EIA. 4. Assessment of environmental conditions (air pollution, surface and ground water

pollution, soil pollution, state of vegetation and fauna, terrestrial and aquatic landscapes, waste disposal).

5. Technical state of the WWTP, system of the WWTP wastewater treatment. 6. Recommended options of the WWTP reconstruction. 7. Activities on works of Phases I and II, including advanced treatment works,

sludge processing works, supporting buildings and facilities. 8. Analysis of the WWTP impacts on environment, soil cover, vegetation, and fauna,

terrestrial and aquatic landscapes after reconstruction. 9. Justification of the selected option with description of advantages and

disadvantages. 10. Dissemination programme.

Public hearings are part of the EIA. It is important to note that for this area serious environmental limitations are absent. Privalenko: Would like to make a few comments. Project envisages scheme of preliminary denitrification providing nitrogen removal. Phosphorous will be removed in pre-aerators. Sludge from primary and secondary settlement tanks will be transported to

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methane tanks for digestion. Then digested and compacted sludge will be suitable for utilization. It is better to use biological treatment with chemical settlement of phosphorous because in this case treated WWTP effluents will comply both with drinking water quality norms and norms for water bodies used for fisheries purposes. Khovansky: I would like to say some words about our work. Impact assessment was given for each option in compliance with the WB requirements. Final objective of project activities is to reduce euthrophication level both in the Lower Don basin and in the Azov and Black seas. Thus, both point and diffuse pollution sources located downstream and upstream Rostov should be considered. Agricultural flow is very important as well. Data on decline of water body pollution as a result of the Rostov WWTP reconstruction is given in the report. Water body was studied as a sole complex (biota, water, bottom sediments). Only biological treatment and biological treatment with chemical removal of phosphorous will decrease pollution load on water bodies. Final objective is to achieve conformity with stated water quality standards. We support option with chemical settlement proposed by SWECO because it will enable to achieve stated goals. Nikanorov: How much the project cost will increase if deep treatment method is used? Khovansky: We don’t have this information. Now planners are carrying out necessary calculations. Nikanorov: But do you know the difference? Khovansky: Unfortunately, I don’t have information. Our task was to complete the environmental impact assessment. Shustov: This is technical side of the project and responsibility of experts involved in project design and estimates. I would like to emphasize that water body will benefit from all proposed options as environmental load on water bodies will reduce. Rodionova: Past projects envisaged construction of methane tanks. Thus, I have two questions:

Will be methane tanks operating this time? Have you considered or abolished reasons for which they were unable to operate earlier?

Does mechanical dewatering plant provide full treatment? Isn’t it enough to achieve necessary level of treatment?

Privalenko: Planners will address these issues. We assessed technogenic impact on environment during reconstruction and after construction under condition that all designed facilities will operate. Shustov: We studied only environmental impact of the proposed options. Lavrenov: Planners are not here yet, although they were invited. By the middle of August Feasibility Study will be ready. Estimates will be part of the Feasibility Study. At present there is no sludge drying in centrifuges installed at mechanical dewatering plant. Thus, helminthes ova present in sludge preventing its further use. Proposed mesophilic digestion will enable to use sludge. Shustov. Mrs. Rodionova’s questions will be considered in the Feasibility Study. Kazaryants: Different foreign companies assisted in Feasibility Studies, including Jacobs (UK). According to estimates about USD10 million will be required for implementation of a deep treatment project. This more than twice of what is available at present time. Again, final option is not selected yet and it is extremely difficult to assess environmental impact due to absence of this final decision. Ignatiev: Reduction of phosphorous concentration at the dispersion site from 0.16 mg/l to 0.15 mg/l is insignificant. It is unclear where did you get this figures. Will it be effective

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for the river? Data given in the report is unjustified. Shustov: Water in the Don River is a result of all discharges. System approach is very important. Funds are allocated to Russian Federation and there is no need to reject them. Nikanorov: Basically two options are considered: with chemical removal of phosphorous and without chemical removal of phosphorous. Is it really worth it, if decline in concentration is only 0.01 mg/l? Khovansky: This question is rightful and in due time. Point sources are scattered along the Don River. Rostov WWTP is one of the largest pollutants in terms of organic pollution. Figures presented in this work are examples of positive impact on water quality due to the WWTP reconstruction. Vodokanal poses a significant impact on the Lower Don water quality and river basin will benefit anyway. In percentage phosphorous concentration will reduce insignificantly. But decrease in mass of phosphate compounds discharged by the WWTP into the Don River will be considerable. At present it is difficult to assess its impact on water quality. Ignatiev: Such estimates will be interesting because it is necessary to know change of river water quality after the WWTP reconstruction. Justification should be convincing. In the EIA everything should be carefully studied for each option with a proper justification. Khovansky: Difficulties with correct estimates are due to lack of reliable information about concentration of pollutants in the Lower Don water. It should be mentioned that even such insignificant decline in nutrient concentration could be important for a change of aquatic landscapes environment; it could promote conversion of reduction situation into oxidizing favourable for aquatic ecosystem. This will prevent secondary pollution of water and entail other favourable consequences, including restoration of ambient water and bottom sediments quality. Cumulative positive effect should be expected if this small percents of nutrient load reduction to be reproduced in other basin parts. Ignatiev: Did you consider problem with alums to be used at the WWTP? Karakulev: Alums (although a definition but not a correct one) is the most widespread coagulant used in Russia at the WWTP. Rostov Vodokanal also uses alums. So far there were no problems with their use. Back to methane tanks issue. In the USSR only 7-8 methane tanks were in a real operation (Riga, Moscow, Minsk, etc.). In Rostov methane tanks were constructed on the WWTP Phase I but special equipment and instrumentation was not installed. Of two methane tanks only one was working but only for 9-11 months. Then methane tank was closed after emergency emission of digested sludge and remained unused for many years. Instead of methane tanks aerobic mineralizers were used. Rodionova: Why did methane tanks were not part of Feasibility Study developed in 1999? Karakulev: This is not really true. That Feasibility Study considered options with use of methane tanks, landfill for sludge disposal and sludge use/processing. The last one was adopted as a working one. Bessmertny: How are you going to accumulate and utilize sludge after application of aluminium sulphate? Karakulev: Sludge will be disposed to a landfill without further use for any purposes. Tsapkova: This is not the best option. At present sludge can be used for decorative purposes. Wide use of sludge for land-reclamation will be limited in case of chemical

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settlement of phosphorous. Nothing is said about sludge management and its future use. Thus, working on Feasibility Study it is important to make estimates for activities on sludge use and its disposal to a special landfill. Karakulev: Proposals to set up a special landfill for sludge disposal were presented several times. But no answer received so far. Five years ago funds for such a landfill were allocated in the framework of the WB project. But Vodokanal decided to redistribute funds for other activities, e.g. to replace two water mains. We are actively using German experience of waste management. There WWTP sludge of large cities is disposed on landfills without further use. Tsapkova: Sludge management is not covered in the project. Karakulev: Feasibility Study is not ready yet. Also, sludge management is not task of the present project. Bessmertny: Still, you need to make decision on final waste disposal. Karakulev: If we are going to use sludge in agriculture then we can’t use chemicals. Processing will result in sludge accumulation; will increase tanks capacity and capital costs. Kazaryants: We are discussing work undertaken by ecologists. We are not making final decisions on the proposed technical scheme. Ecologists can propose recommendations to solve possible problems. They can be included into the Feasibility Study. Today’s meeting objective is to select option that will be most suitable in terms of environmental impact. This was covered by the presentation. Ignatiev: According to the presentation we can recommend biological treatment with detailed review of this option and with preparation of final proposals. Bessmertny: Further increase of effluents volume is likely, and aluminium sulphate will not help if capacity will be insufficient. Water disinfection and extraction of chlorine residue is a vital issue. This wasn’t covered in technology description. In Azov water samples contain 15% - 100% viruses. It is necessary to remove chlorine residue and thus, the issue should be mentioned in project materials and technological scheme. Kazaryants: We have a unique opportunity to solve part of our problems using GEF grant. Before final decision we will consider all your comments and proposals. They will all be included in meeting minutes and will be incorporated into an updated EIA report. Mr. Kazaryants promised to consider all the comments and to include them into Feasibility Study document and the EIA report. Opened public hearings were finished.

The following decisions were adopted in accordance with the agreed agenda: To include stated comments and proposals into an updated version of the EIA report. To present completed document within 1 week for review and approval by the project

implementation group.

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Annex 3 Project booklet (in Russian) Введение

Правительство Российской Федерации получило Грант от Глобального Экологического Фонда в размере 324000 дол. США для подготовки Проекта по сокращению сбросов биологически-активных веществ и выбросов метана с очистных сооружений канализации в г. Ростове-на-Дону.

Долгосрочной целью Проекта является снижение уровня эвтрофикации Азовского и Черного морей путем сокращения сбросов соединений азота и фосфора и уменьшение объема выбросов парниковых газов в атмосферу.

Ближайшими целями Проекта являются:

Сокращение сбросов биологически-активных веществ (азота и фосфора) в р. Дон, посредством реконструкции и усовершенствования системы очистки сточных вод на очистных сооружениях канализации МУП ПО «Водоканал» г. Ростова-на-Дону.

Сокращение объема образующегося осадка сточных вод и снижение органического вещества в сточных водах путем сбраживания и обезвоживания осадка на ОСК г. Ростова-на-Дону.

Сокращение эмиссии метана от иловых осадков ОСК г. Ростова-на-Дону посредством сбора метана, образующегося при переработке осадка сточных вод, использования собранного метана для выработки электроэнергии и утилизации тепла.

Разработка программы распространения опыта по сокращению сбросов биологически-активных веществ и выбросов метана на муниципальных предприятиях канализации в другие регионы России и возможно пограничные страны Азово-Черноморского бассейна.

Планируемые мероприятия

Фирмой «SWECO INTERNATIONAL» как основной

предлагается вариант очистки сточных вод, предусматривающий биологическую очистку и доочистку сточных вод, удаление фосфорных соединений с помощью химических реагентов, сбраживание осадка сточных вод в метантенках для уменьшения выбросов «парниковых» газов в атмосферу, и использование образующегося метана в качестве топлива на проектируемой электростанции. Модернизация ОСК планируется поэтапно из-за ограниченности финансовых ресурсов.

На промежуточном этапе производительность ОСК составит 360000 м3/сутки. Общая мощность ОСК на долгосрочную перспективу составит 460000 м3 сточных вод в сутки, этот поток распределяется по 50% на две очереди. Усовершенствование ОСК позволит достичь в очищенных сточных водах уменьшения концентрации фосфора на 60%, полного азота – на 50%. Конечные показатели для очищенных сточных вод ОСК г. Ростова-на-Дону будут соответствовать существующим нормам.

Альтернативные варианты достижения цели

На этапах реконструкции и последующей эксплуатации ОСК будет происходить различного рода воздействие на окружающую среду за счет выбросов загрязняющих веществ в атмосферу, сбросов сточных вод в р.Дон, образования и размещения отходов производства и потребления, других видов воздействия. Для проведения оценки воздействия на окружающую среду выбраны следующих три альтернативных варианта достижения цели намечаемой хозяйственной деятельности: - Нулевой вариант – сохраняется

существующее положение на ОСК, никакая модернизация не проводится.

- Вариант, предусматривающий биологическую очистку, доочистку сточных вод и химическое удаление фосфора.

- Вариант, предусматривающий снижение биогенных веществ только с помощью биологической очистки сточных вод.

Существующая ситуация в воде р.Дон

В воде реки Дон на участке от Цимлянского водохранилища до устья содержание меди, железа (летом), фенолов (летом), органического вещества (БПК5), сульфатов и нитритов (зимой) превышает ПДК. В устье реки Дон загрязненность воды повышалась во все сезоны по содержанию сульфатов, минерализации вод и нефтепродуктов, а зимой – по нитритам, БПК5, железу. Наиболее загрязненными являются участки реки в районе городов Аксай, Ростов, Азов (по БПК5, нефтепродуктам – независимо от сезона, нитратам – зимой, фенолам – летом).

На устьевом участке р. Дон происходит периодическое усиление процесса антропогенного эвтрофирования. Максимально высокие значения численности фитопланктонных сообществ отмечаются в летне-осенний период, когда отмечаются заметные изменения структуры сообществ за счет модификации видового состава доминирующего комплекса и тенденции выхода на ведущее положение отдельных видов.

По данным центров Госсанэпиднадзора городов Ростова-на-Дону, Азова, Таганрога, Азовского района в воде р.Дон в местах водозаборов и зон рекреаций населенных мест отмечаются превышения гигиенических нормативов по БПК5 (1,5–2 ПДК), ХПК (1,5–3,5 ПДК), общей жесткости (1,2–1,5

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ПДК), общему железу (1,3–5,1 ПДК), нефтепродуктам (1,2–32 ПДК).

По показаниям бактериального загрязнения р. Дон относится к источникам с повышенной степенью эпидемиологической опасности. В речной воде обнаруживаются колифаги, споры сульфитредуцирующих клостридий, холероподобная микрофлора. Высокий уровень бактериального загрязнения речной воды отмечается в устьевой части р. Дон, особенно на участке реки ниже сбросов городской канализации г. Ростова-на-Дону и при впадении р. Темерник. Наиболее напряженная ситуация с качеством воды по микробиологическим показателям сложилась в месте водозабора г. Азова из-за сброса в р. Дон недостаточно очищенных и неочищенных сточных вод г. Ростова-на-Дону. Использование населением питьевой воды с бактериальным и вирусным загрязнением приводит к возникновению острых кишечных инфекций и вирусного гепатита «А».

Обоснование выбранного варианта реконструкции ОСК

Анализ экологических условий и технической возможности реконструкции ОСК для достижения целевых показателей степени очистки сточных вод показал, что вариант реконструкции ОСК, предусматривающий биологическую очистку, доочистку сточных вод и химическое удаление фосфора с уплотнением осадка в метантенках (сбраживанием), сбором и утилизацией образующегося метана на проектируемой теплоэлектростанции, является наиболее предпочтительным:

- При реконструкции ОСК будет достигнута более высокая

степень очистки сточных вод, сбрасываемых в р. Дон, содержание загрязняющих веществ в которых будет соответствовать установленным требованиям нормативов ПДС и действующим нормативным документам. Это позволит повысить качество речной воды и уменьшить уровень эвтрофикации реки в ее нижнем течении и Таганрогском заливе.

- Особую опасность для водных экосистем представляют соединения фосфора, которые являются лимитирующим фактором для развития многих организмов, в том числе, зеленых и сине-зеленых водорослей, обусловливающих «цветение» речной воды. Дополнительной очисткой сточных вод от фосфорных соединений с помощью химических реагентов опасность эвтрофикации речных вод будет значительно уменьшена.

- При сбраживании и уплотнении илового осадка произойдет уменьшение его объема, что облегчает проблему временного хранения осадка на территории ОСК, и заметно снизит опасность загрязнения подземных вод при фильтрации иловых вод.

- Сжигание образующегося биогаза на собственной теплоэлектростанции позволит не только уменьшить выбросы метана в атмосферу, но и уменьшить общее количество «парниковых» газов, выделяющихся в атмосферу как на территории ОСК, так и при выработке электроэнергии на Новочеркасской ГРЭС.

- Достоинствами данного варианта являются надежная, хорошо документированная технология процесса. Средства управления просты – легко поддерживать высокую эффективность удаления фосфора путем контроля доз реагента.

- К недостаткам данного варианта следует отнести более сложную технологию очистки

сточных вод, дополнительные затраты на химическое удаление фосфора.

РОССИЙСКАЯ ФЕДЕРАЦИЯ

МУП ПО «ВОДОКАНАЛ» г. РОСТОВА И АДМИНИСТРАЦИЯ

РОСТОВСКОЙ ОБЛАСТИ

Проект по сокращению сбросов биогенных веществ и выбросов

метана в г. Ростове-на-Дону

Оценка воздействия на окружающую среду

ООО Южно-Русский Центр подготовки и реализации международных проектов

(ЦПРП-Юг)

Ростов-на-Дону июнь 2004

130

Annex 4 Project leaflet (in Russian)

Жители Дона, казаки и дачники!

При использовании моющих средств («Тайд», «Ариэль» и другие широко разрекламированные стиральные порошки) содержащийся в них фосфор в конечном итоге поступает в р.Дон, что приводит к цветению речной воды и ухудшению условий жизни и размножения донской рыбы. Применение стиральных порошков на основе цеолитов исключает загрязнение реки фосфором. Для сохранения чистой воды в реке Дон используйте моющие средства, не содержащие фосфора!