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D.E. JardineFisheries, Aquacultureand Environment

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Source Separation Reduces Waste and Leachate Strength on Prince Edward Island, Canada

D. E. Jardine, Prince Edward Island Department of Fisheries, Aquaculture & Environment

P.O. Box 2000, Charlottetown, Prince Edward Island, Canada, C1A 7N8 dejardine@gov.pe.ca

Abstract: The East Prince Waste Management Facility commenced operations in December 1994 at Wellington Center, Prince Edward Island. The waste cell at this facility receives only source separated waste materials. The Waste Watch source separation program is a three stream system with recyclables and compostables separated at source from remaining waste. This has resulted in a 65 % diversion of residential and ICI waste from disposal. The leachate quality in the waste cell has been monitored and compared with leachate quality reported in the literature from traditional mixed waste landfill sites. The concentrations of several parameters including: Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), chloride, calcium, sodium, lead and other parameters are considerably reduced. The source separation system developed in Prince Edward Island prevents pollution in a number of ways:

• Reduced landfill space for disposal operations (65% reduction) • Reduced leachate strength (over 90% for some parameters) • Reduced greenhouse gas emissions • Reduced resources required for treatment of leachate • Reduced dependency on chemical fertilizers from the manufacture of compost • Reduced use of virgin materials by recycling various commodities

The Waste Watch system is currently being expanded to the entire Province of Prince Edward Island resulting in the province becoming the first jurisdiction in North America to attain a fully operational source separation system for all sectors by 2002. Keywords: source separation, leachate strength, composting, waste reduction, methane Introduction Prince Edward Island is located on the east coast of Canada and is bounded by the Gulf of the St. Lawrence River (see Figure 1).

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Figure 1 Map Showing Prince Edward Island Location

Prince Edward Island is Canada’s smallest province with an area of 2184 m2 or 5660.4 km2. The provincial population is 138,900 (Statistics Canada) and the population density is 24.5 per km2 making the province the most densely populated in Canada. The total annual average precipitation is 1100 mm or 42 inches. Some of this precipitation infiltrates into the permo-carboniferous red bed aquifer composed mainly of sandstones and shales. The aquifer has been characterized as a fractured porous media (Francis et al) and thus is prone to surface and near surface sources of contamination. Prince Edward Island is totally dependant upon groundwater for its source of fresh water thus there is increasing pressure to protect it from contaminant sources and maintain existing groundwater quality. One of the potential contaminant sources is from on land disposal of solid waste. The estimated annual solid waste generation is 120,000 tonnes (Island Waste Management Corporation). This waste has been historically disposed of at a number of open dump sites or landfills which frequently placed garbage directly into the water table or in direct contact with the fractured bedrock. In the early 1990’s the province began to search for new methods of managing its waste materials. The East Prince Region was served by an assortment of eight (8) disposal sites scattered throughout the region. The search began in 1991 as the largest disposal site in

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the area, serving the Town of Summerside and adjacent communities was reaching capacity. In 1992 a new source separation system entitled, “Waste Watch” was conceived by a joint committee of ten (10) local municipalities and the provincial environment agency.

Figure 2 – Map showing East Prince Region of Prince Edward Island

Source Separation Program The Waste Watch source separation program began with a pilot project involving 100 households in the East Prince region of Prince Edward Island (see figure 2). The pilot project resulted in the program being expanded and eventually the entire East Prince region, with a population of approximately 11,000 households (30,000 people), including 1200 businesses mandated to implement the system. All homes and businesses source separate their waste prior to pick up by a collector. The area served was expanded in 1997 and 1998 to include an additional 1400 homes and 100 businesses located in Central Prince County and the Cambridge area of Kings County. The Waste Watch System is a three stream program. All recyclable products are recovered for recycling and organic waste is recovered for composting. Table 1 gives a list of the items currently recycled and composted.

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Table 1- Items Recycled and Composted Rccyclable Items Compostable Items Corrogated cardboard Non recyclable paper, paper towels etc. Newsprint Food waste, including meat and bones Office papers Fish and dairy products Glossy papers Paper food wrap Glass, clear and colored Boxboard containers and packaging Metal cans, aerosol cans, other metal products Leaves and yard waste Plastics #’s 1 to 5 Other organic matter White goods Aseptic packages Milk / juice cartons Dry cell and Ni – Cd batteries There are also some reduction and reuse programs in place to assist with the diversion of waste from disposal. Some examples include:

All flavored and carbonated beverages and beer must be in refillable containers A deposit refund system for liquor and wine bottles Used motor oil must be accepted for recycling by the seller (or a designate) Used lead acid batteries must be accepted for recycling by the seller Rechargeable batteries are accepted for return by certain retailers White goods are accepted free of charge at the waste management facility Household hazardous waste is accepted free of charge at the waste management

facility and disposed of at licensed facilities out of province. A used tire collection and drop off system is in place A collection system for used cooking oils is available

The remaining waste material, essentially free of organic matter is placed in waste cells at the East Prince Waste Management Facility located at Wellington Center, Prince County. Waste Management Facility The East Prince Waste Management Facility was commissioned on December 5, 1994. All waste materials placed at this facility must be source separated to satisfy the requirements of the provincial environmental assessment approval. The facility consists of a scale and scale house, landfill cells, indoor windrow composting facility, exterior compost curing area, household recycling center, white goods storage area, household hazardous waste storage facility and yard waste storage area. The non-organic waste is placed in composite lined cells with an 80 mil - high density polyethylene liner underlain by a compacted clay liner with a permeability of less than 1 X 10-7 CM/sec. A typical landfill cell is shown in Figure 3.

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Figure 3

The landfill footprint covers a total area of 7.2 hectares and this is divided into six cells with three of these cells constructed and in operation. The landfill has a design depth of 14.5 m with outer sideslopes of 4:1 and an ultimate landfill volume of 740,000 m3. The estimated specific weight of the waste placed in the cells is 0.4 tonnes/m3. The waste is covered daily using an alternate daily cover of a degradable plastic film with a sand blanket. Completed cell areas have an intermediate cover of 300 mm of topsoil and eventually a final cap consisting of a 300 mm sand blanket, an LDPE geomembrane, a 300 mm sand drainage layer and 150 mm of final topsoil. The quantity of waste deposited in the waste cells up to December 31, 2000 is provided in table 2. Table 2 – Waste Generation Data Year Total Waste Generation

(Tonnes) Compost Processed (Tonnes)

Waste Deposited (Tonnes)

Diversion Rate1 (%)

1995 23,560 6,681 9,315 60.51996 25,303 8,037 8,911 64.81997 26,460 8,742 9,166 65.51998 29,362 9,831 10,255 65.11999 30,990 9,702 11,058 64.32000 31,719 10,113 11,235 64.5Totals 167,394 53,106 59,940 64.21diversion rate includes waste diverted by reduction and reuse programs All leachate from the landfill cell is collected via a network of piping, a collection sump and a 90,000 litre double walled fiberglass underground storage tank and taken off-site

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for treatment. The leachate has a limited residence time in the landfill cell to minimize the contact time with the buried waste materials. Leachate Quantity and Quality All leachate is collected for off-site treatment and table 3 documents the amount of leachate collected and the annual precipitation at the Slemon Park weather station located 9 km to the north of the site.

Table 3 Year Annual Precipitation (mm) Leachate Quantity (L) 1995 952.1 2,316,610.8 1996 1185.8 4,506,390.7 1997 978.1 2,697,376.8 1998 1298.3 10,330,761.8 1999 1076.61 9,017,626.5 2000 1195.01 8,863,861.3

1 Precipitation data for 1999 and 2000 is from a rain gauge at New London, PEI The leachate at the East Prince Facility has been sampled regularly since the site opened. Three main indicators of leachate strength and quality are biological oxygen demand (BOD), chemical oxygen demand (COD) and total suspended solids (TSS). Figure 4 graphically presents the results of analysis for these parameters up to June, 2001. The concentrations of BOD and COD in the leachate from the East Prince facility are certainly well below the concentrations expected in landfills where organic materials are present. Typical mixed waste leachate for a new landfill can range in organic strength from 2,000 to 30,000 mg/L BOD and 3,000 to 60,000 mg/L COD. The concentration of inorganic constituents in the leachate from this site is presented in table 4.

Figure 4WELLINGTON CENTER LEACHATE STRENGTH

0

1000

2000

3000

4000

5000

6000

July 20/95 Sept. 27/95 Mar. 13/96 Mar. 11/97 Mar 3, 1998 Feb 24, 1999 Mar 7, 2000 Nov. 29,2000

BOD mg/LCOD mg/LSS mg/L

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Table 4 – Inorganic Chemistry

Parameter Units Samples Min. Max. Avg. Std. Dev. Alkalinity Mg/L 23 63.0 2165.0 638.8 637.6 Ammonium-N Mg/L 25 nd1 226.0 78.7 80.8 Barium ug/L 7 nd 600.0 286.3 207.1 Biological Oxygen Demand Mg/L 45 37 3000 872.6 692.4 Cadmium Mg/L 28 nd 0.14 .005 .026 Calcium Mg/L 28 24.3 384.5 147.2 111.7 Chemical Oxygen Demand Mg/L 43 450 5200 1793.4 964.8 Chloride Mg/L 28 15 902 347.4 303.5 Chromium Mg/L 28 nd 0.06 nd ----- Copper Mg/L 28 nd nd nd ----- Iron (ext.) Mg/L 28 0.19 55.42 13.01 14.14 Lead Mg/L 26 nd 0.007 Nd ----- Magnesium Mg/L 28 5.68 71.26 29.51 21.03 Manganese Mg/L 28 1.97 199.6 56.83 62.13 Mercury Ug/L 6 nd 0.54 0.30 0.23 Nickel Mg/L 28 nd 0.05 nd ------ Nitrate-N Mg/L 27 nd 4.5 0.22 0.86 Nitrogen-Tot Mg/L 18 0.8 281.4 76.8 95.1 PH Units 27 6.3 7.6 6.8 0.4 Potassium Mg/L 27 3.5 267.9 88.4 92.2 Sodium Mg/L 28 5.1 659.4 246.4 225.7 Strontium Ug/L 8 77 880 452.1 264.1 Sulfate Mg/L 28 15.46 212.8 74.7 45.7 Total Solids Mg/L 44 16 560 171 133 Zinc Mg/L 28 nd 0.41 0.10 0.11 1nd = non detectable Benefits of the Source Separation System The Waste Watch source separation system has been highly successful and has diverted 65% of the waste stream from disposal. Eight (8) disposal sites previously operating in the area were replaced by a single waste management facility. This has reduced the requirement for landfill space and reduced the potential for groundwater contamination by a significant factor. A significant reduction in leachate strength is evident from a comparison of the leachate quality data from the Wellington Center Facility with reported leachate quality from mixed waste landfills in other jurisdictions. Table 6 provides a comparison of the data from the source separated site at Wellington Center with data reported by Jones-Lee et al for municipal waste landfills.

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Table 6 – Source Separated Versus Mixed Waste Leachate Parameter Units East Prince Avg. Conc. Mixed Waste (Jones-Lee et al)BOD Mg/L 873 10,500 COD Mg/L 1793 15,000 Total Solids Mg/L 171 16,000 Ammonia Mg/L 78.7 300 Alkalinity (total) Mg/L 639 3,600 pH Mg/L 6.8 6.3 Calcium Mg/L 147 1,000 Magnesium Mg/L 29.5 700 Sodium Mg/L 246 700 Chloride Mg/L 347 980 Sulphate Mg/L 75 380 Chromium Mg/L nd 0.9 Cadmium Mg/L .005 .05 Copper Mg/L nd 0.5 Lead Mg/L nd 0.5 Nickel Mg/L nd 1.2 Iron (ext.) Mg/L 13 430 Zinc Mg/L 0.1 21 Nitrate (N) Mg/L 0.2 4 Parameters of concern for management of leachate at wastewater treatment facilities are shown on Figure 5.

BOD COD TSS

05000

100001500020000

Figure 5Leachate Quality Comparison - BOD, COD, TSS

Waste Watch 873 1793 171

Typical Mixed Waste 10,500 15,000 16,000

BOD COD TSS

The East Prince leachate shows a significantly reduced strength when compared to a typical mixed waste landfill (Jones-Lee and Lee). The concentration of BOD is over 90% lower than the concentration in a conventional landfill site receiving mixed waste. COD and TSS also both show nearly a 90% reduction in concentration.

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The concentrations for the major ions depicted on Figure 6 also show significant reductions when compared with conventional landfill sites.

Ca Cl Na

Waste WatchMixed Waste Landfill0

200400600800

1000

Figure 6Leachate Quality Comparison - Ca, Cl, Na

Waste Watch 147 347 246

Mixed Waste Landfill 1,000 980 700

Ca Cl Na

As shown on Table 2 a total of 53,106 tonnes of organic matter has been composted at the East Prince facility up to the end of the year 2000. The composting process is an aerobic process as opposed to the anaerobic process in the waste cells of landfill sites. A primary reason for maintaining an aerobic decomposition is to avoid the production of methane gas, documented by the USEPA to have a global warming potential 21 times greater than carbon dioxide. Hudgins and Green have documented the generation of methane can be mitigated by using an aerobic landfill system. Hudgins and Green found that the production of methane could be reduced by over 90 per cent by maintaining an aerobic process within landfill cells in Georgia, USA. In another study in Addis Ababa, Ethiopia by Tessema, the author demonstrates that composting is an effective means of accomplishing methane gas reduction. Greenhouse gas reduction is another benefit of the source separation system in the East Prince region. The production of a compost product can also reduce the dependency on chemical fertilizer for agricultural food production. (MacLeod et al) Prince Edward Island soils are deficient in organic matter with an average concentration in the range of three (3) per cent Research conducted by MacLeod and others has documented that the use of compost can reduce the dependency on chemical fertilizer in agricultural production. This is another important benefit of recovering and reusing organic resources traditionally dumped and buried.

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Conclusion Separation at the source is an effective method of reducing the environmental impact of solid waste resources. In particular, the removal of organic matter from disposal cells and reusing it as a soil amendment creates a number of environmental benefits contributing to the prevention of pollution including a 65% reduction in the quantity of landfilled waste and a significant reduction in leachate strength. This diversion will enable Prince Edward Island to exceed Canada’s national diversion goals and provide a contribution to a reduction in greenhouse gas emissions to meet national and international commitments. Acknowledgements The author wishes to acknowledge the assistance of Heather Chowen and Claudette Gallant of the Island Waste Management Corporation and Cindy MacLeod of the Prince Edward Island Department of Agriculture and Forestry for their assistance in supplying information and data for this paper. References CBCL Limited, March 1998, “East Prince Waste Management Facility, Leachate Treatment Study”, prepared for the Prince Edward Island Department of Fisheries and Environment. Douglas, B.W., MacLeod, J.A., Mellish, T.M., Glen, W.M., Thompson, B.L., DeHaan, K.R., Sturz, A.V. , Carter, M.R., Brimacombe, M.B., 2000, “A Method for Measuring Prince Edward Island Soil Quality”, Communications in Soil Science and Plant Analysis, 31(11-14), 1837-1845. East Prince Waste Management Commission, Annual Reports, 1995 to 1998. Environment Canada, 2001, Precipitation Records for Summerside and New London Weather Stations, Atlantic Climate Centre, Meteorological Service of Canada, Fredericton, NB Francis, R.M., Gale, J.E., and Atkinson, L.C. (1984), “Characterization of Aquifer Zones in a Fractured Porous Media.” Proceedings of the International Groundwater Symposium on Groundwater Resources Utilization and Contaminant Hydrogeology, Montreal, V. 1, pp.33-43. Hudgins, Mark and Green, Leon, Second International Methane Mitigation Conference, Novosibirsk, Russia, June 21, 2000, Innovative Methane Mitigation Using An Aerobic Landfill System. Island Waste Management Corporation, Annual Reports, 1999 and 2000. Jardine, D.E. and Chowen, H.D., 1999, Proceedings of the International Composting Symposium, Sept. 19 – 23rd, 1999, Halifax/Dartmouth, Nova Scotia, Canada, “Quality Compost From Source Separated Organic Material and Biosolids in East Prince County, Prince Edward Island.”

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Jones-Lee, Anne, and Lee, G. Fred, “Groundwater Pollution by Municipal Landfills: Leachate Composition, Detection and Water Quality Significance”, Sardinia ‘93IV International Landfill Symposiums. Margherita di Pula, Italy, 11-15 October 1993. MacLeod, J. A., Sanderson, J.B., Douglas, B., Henry, R, 1998, “Use of Municipal Compost in Potato Rotation.” Report to 1998 Annual Meeting Compost Council of Canada. Pupp, Dr. Christian, Francis, R.M., Jardine, D.E., Grove, Gary, Oct. 1990, “Groundwater Quality in Prince Edward Island Hydrogeology, Quality Concerns, Management”, National Hydrology Research Institute, Contribution No. CS-90124, Environment Canada, Conservation and Protection. Statistics Canada, 2001, Cansim II, Table 051-001. Tessema, Fikru, Second International Methane Mitigation Conference, Novosibirsk, Russia, June 21, 2000, Integrated Municipal Solid Waste Management: Managing Towards Mitigating Methane Emission. Case Study Analysis. USEPA, 2001, USEPA Global Warming Site: National Emissions – Global Warming Potentials. (http://www.epa.gov/globalwarming/emissions/national/gwp.html) Biography: Don Jardine is the Director of Pollution Prevention for the Prince Edward Island Department of Fisheries, Aquaculture & Environment in Charlottetown. He was involved with the development of the Waste Watch source separation program since its inception in 1992. He has worked in various activities related to pollution prevention, including groundwater protection for over 25 years.