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Upper York Sewage Solutions Environmental Assessment
Technical Concept Level 2 Document
Prepared for: The Regional Municipality of York
Prepared by:
JUNE 2013REF. NO. 050278 (81) YORK REGION NO. 74270
Conestoga-Rovers & Associates
1195 Stellar Drive, Unit 1 Newmarket, Ontario L3Y 7B8
050278 (81) York Region No. 74270
Technical Concept Level 2 Document Upper York Sewage Solutions IEA
Table of Contents Page
1.0
2.0
3.0
Introduction 3
Description of the Short List of Alternative Water Reclamation Centre Sites and York Durham Sewage System Modifications Alternative Routes 5 2.1 Short List of Alternative Water Reclamation Centre Sites 5 2.2 YDSS Modifications Alternative Routes 13
Description of the Lake Simcoe Water Reclamation Centre Concept Design 17 3.1 Design Overview 17 3.2 Process Flow Diagrams 18 3.3 Water Reclamation Centre Sizing and Layout Requirements 23 3.3.1 Water Reclamation Centre Facilities Sizing and Services 23 3.3.2 Site Layout Constraints and Objectives 25 3.3.3 Wastewater Conveyance to Water Reclamation Centre 27 3.3.4 Treated Effluent Outfall from the Water Reclamation Centre 31 3.3.5 Carbon Footprint 32 3.4 Alternative Water Reclamation Centre Site Layouts 33 3.4.1 Site 24 33 3.4.1.1 Site 24 Facility Layout 33 3.4.1.2 Site 24 Geotechnical Assessment and Structural Design 35 3.4.1.3 Conveyance Infrastructure To/From Site 24 35 3.4.1.4 Site 24 Servicing and Access 37 3.4.1.5 Site 24 Carbon Footprint 37 3.4.2 Site 30 38 3.4.2.1 Site 30 Facility Layout 38 3.4.2.2 Site 30 Geotechnical Assessment and Structural Design 40 3.4.2.3 Conveyance Infrastructure To/From Site 30 40 3.4.2.4 Site 30 Servicing and Access 43 3.4.2.5 Site 30 Carbon Footprint 43 3.4.3 WH1 West 44 3.4.3.1 Site WH1 West Facility Layout 44 3.4.3.2 Site WH1 West Geotechnical Assessment and Structural Design 46 3.4.2.3 Conveyance Infrastructure To/From Site WH1 West 46 3.4.3.4 Site WH1 West Servicing and Access 48 3.4.3.5 Site WH1 West Carbon Footprint 49 3.4.4 WH1 East 49 3.4.4.1 Site WH1 East Facility Layout 49 3.4.4.2 Site WH1 East Geotechnical Assessment and Structural Design 52 3.4.4.3 Conveyance Infrastructure To/From Site WH1 East 52
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Technical Concept Level 2 Document Upper York Sewage Solutions IEA
Table of Contents Page
4.0
5.0
6.0
7.0
8.0
3.4.4.4 Site WH1 East Servicing and Access 54 3.4.4.5 Site WH1East Carbon Footprint 55 3.4.5 WH2 55 3.4.5.1 Site WH2 Facility Layout 55 3.4.5.2 Site WH2 Geotechnical Assessment and Structural Design 57 3.4.5.3 Conveyance Infrastructure To/From Site WH2 57 3.4.5.4 Site WH2 Servicing and Access 59 3.4.5.5 Site WH2 Carbon Footprint 60
YDSS Modifications Alternative Routes 61 4.1 Route A 61 4.2 Route B 62 4.3 Route C 63
Summary 65
References 66
List of Abbreviations 67
Glossary of Terms 69
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Technical Concept Level 2 Document Upper York Sewage Solutions IEA
List of Figures
Figure 2.1 Locations of Water Reclamation Centre Alternative Sites 7 Figure 2.2 Site 24 Water Reclamation Centre Site Layout 8 Figure 2.3 Site 30 Water Reclamation Centre Site Layout 9 Figure 2.4 Site Willing Host 1 West Water Reclamation Centre Site Layout 10 Figure 2.5 Site Willing Host 1 East Water Reclamation Centre Site Layout 11 Figure 2.6 Site Willing Host 2 Water Reclamation Centre Site Layout 12 Figure 2.7 Existing YDSS Located in the YDSS Area 14 Figure 2.8 Alternative Route A, Alternative Route B and Alternative Route C 15 Figure 3.1 Process Flow Schematic – Conventional Treatment 20 Figure 3.2 Process Flow Schematic – Advanced Treatment 21 Figure 3.3 Process Flow Schematic – Solids Management 22 Figure 3.4 Locations of Water Reclamation Centre Alternative Sites and
Queensville, Holland Landing, Sharon, Wastewater Servicing Project 29
Figure 3.5 Queensville, Holland Landing, Sharon, and North –West Newmarket Wastewater Servicing Strategy Upon Construction of the Water Reclamation Centre 30
Figure 3.6 Site 24 Water Reclamation Centre Site Layout 34 Figure 3.7 Site 24 Water Reclamation Centre & Associated Conveyance
Infrastructure Routes 36 Figure 3.8 Site 30 Water Reclamation Centre Site Layout 39 Figure 3.9 Site Water Reclamation Centre & Associated Conveyance
Infrastructure Routes 42 Figure 3.10 Site WH1 West Water Reclamation Centre Site Layout 45 Figure 3.11 Site WH1 West Water Reclamation Centre & Associated
Conveyance Infrastructure Routes 47 Figure 3.12 Site WH1 East Water Reclamation Centre Site Layout 51 Figure 3.13 WH1 East Water Reclamation Centre & Associated Conveyance
Infrastructure Routes 53 Figure 3.14 Site WH2 Water Reclamation Centre Site Layout 56 Figure 3.15 WH2 Water Reclamation Centre & Associated Conveyance
Infrastructure Routes 58
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Technical Concept Level 2 Document Upper York Sewage Solutions IEA
List of Tables
Table 3.1 Water Reclamation Centre Site Layout – Facility Sizing 24 Table 3.2 Facilities Included within Air Separation Zone 26 Table 3.3 Carbon Footprint for Water Reclamation Centre Site 24 38 Table 3.4 Carbon Footprint for Water Reclamation Centre Site 30 43 Table 3.5 Carbon Footprint for Water Reclamation Centre Site WH1 West 49 Table 3.6 Carbon Footprint for Water Reclamation Centre Site WH1East 55 Table 3.7 Carbon Footprint for Water Reclamation Centre Site WH2 60 Table 4.1 Carbon Footprint for YDSS Modifications – Route A 62 Table 4.2 Carbon Footprint for YDSS Modifications – Route B 63 Table 4.3 Carbon Footprint for YDSS Modifications – Route C 64
List of Appendices
Appendix A: Water Reclamation Centre Design Appendix B: Biowin Modeling Results Summary Appendix C: Geotechnical Report Appendix D: Water Reclamation Centre Site Conveyance Plan & Profile Appendix E: YDSS Modifications Design Appendix F: YDSS Modifications Plan & Profile Appendix G: Carbon Footprint for the Water Reclamation Centre
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Technical Concept Level 2 Document Upper York Sewage Solutions IEA
Executive Summary
This Technical Concept Level 2 Document provides an enhanced concept level design for the preferred Alternative to the Undertaking, building on the work documented in Technical Concept Level 1 Document. Technical Concept Level 2 Document will be used for reference purposes for assessing the short-listed Alternative Methods of Carrying Out the Undertaking, in accordance with the Upper York Sewage Solutions (UYSS) Environmental Assessment Terms of Reference approved by the Minister of the Environment in March 2010. The Regional Municipality of York (York Region) confirmed the Innovative Wastewater Treatment Technologies alternative as the Preferred Alternative for developing a sustainable sewage servicing solution to accommodate the growth forecasted to occur in the UYSS service area. This forecast is in accordance with both the provincial growth management policies outlined in the Growth Plan for the Greater Golden Horseshoe pursuant to the Places to Grow Act, 2005 and applicable environmental legislation including, but not limited to, the Lake Simcoe Protection Act, 2008, the Oak Ridges Moraine Conservation Act, 2001, the Greenbelt Act, 2005, and the Ontario Water Resources Act. The UYSS service area consists of the growth portions of the Towns of Aurora, Newmarket, and portions of East Gwillimbury, including Queensville, Holland Landing, and Sharon. The wastewater servicing capacity required to accommodate only the growth forecasted to occur in the UYSS service area to the year 2031 is 47.2 megalitres per day (MLD) annual average day flow. However, including residences currently serviced by existing private on-site septic systems and residences currently serviced by the Holland Landing Water Pollution Control Plant (Lagoons) in East Gwillimbury, capacity for the UYSS service area of 53 MLD (52.8 MLD) is required. The Preferred Alternative (Innovative Wastewater Treatment Technologies) consists of:
A new 40 MLD Annual Average Day Flow Water Reclamation Centre that would produce treated effluent suitable both for discharge to the East Holland River and reclaimed water applications;
Use of a project specific watershed Total Phosphorus off-setting program (using project specific phosphorus off-sets to maintain the total phosphorus load within the current allocation for the Queensville / Holland Landing Lagoon which would be decommissioned), and;
Modifications to the existing York Durham Sewage System to provide additional system reliability during high flow conditions to accommodate sewage flow from approved growth from the Towns of Aurora and Newmarket.
Lake Simcoe Water Reclamation Centre An advanced treatment process has been selected for the new Lake Simcoe Water Reclamation Centre to produce both final effluent suitable for discharge to the Lake Simcoe watershed and reclaimed water for various end uses. Additionally, the treatment process selected would be capable of reaching the very low Total Phosphorus limits required under the Lake Simcoe Phosphorus Reduction Strategy (2010). In general, the liquid process would
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Technical Concept Level 2 Document Upper York Sewage Solutions IEA
consist of a headworks (screenings and grit removal), primary treatment, flow balancing tanks, conventional activated sludge with biological nutrient removal, chemical addition, secondary clarifiers, and tertiary and quaternary phases consisting of low pressure membranes (microfiltration), high pressure membranes (reverse osmosis), reverse osmosis concentrate treatment, disinfection, and a final outfall. Biosolids management would include primary gravity thickeners/fermenters, waste activated sludge thickening, anaerobic digestion, biosolids storage, and an option for digested sludge dewatering. All unit operations which have the potential to generate odour would be contained and the air treated prior to discharge to the atmosphere. The design of buffer zones around the plant would further reduce the potential for odour incidents occurring off site. York Durham Sewage System Modifications To provide additional system reliability during high flow conditions, the existing YDSS would be updated to accommodate additional flows from the Towns of Newmarket and Aurora. The proposed modifications would provide sufficient capacity for approved growth to 2031 and relief to the existing conveyance system during periods of extreme high flow or during system maintenance operations at the Newmarket, Bogart Creek, and Aurora Pumping Stations. Development of the Short-listed Alternative Methods The short-listed Alternative Methods for Carrying out the Undertaking comprise five locations for the Water Reclamation Centre and three routes for the YDSS modifications. The Conceptual Design and Conceptual Site Layout for the Water Reclamation Centre are described in this document. The adaptation of the Conceptual Site Layout to accommodate each site, together with the required servicing and resulting carbon footprint, are presented. The Conceptual Design, construction methods and carbon footprint for each of the YDSS modifications are also presented.
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Technical Concept Level 2 Document Upper York Sewage Solutions IEA
Section 1.0 Introduction
York Region confirmed the Innovative Wastewater Treatment Technologies (Lake Simcoe Water Reclamation Centre) alternative with York Durham Sewage System (YDSS) Modifications as the Preferred Alternative for accommodating the growth forecasted to occur in the UYSS EA service area to 2031.
This Technical Concept Level 2 Document describes the technical concept design of the Lake Simcoe Water Reclamation Centre and YDSS Modifications in accordance with the Technical Work Plan in Appendix H of the Upper York Sewage Solutions Environmental Assessment (UYSS EA) Terms of Reference approved by the Minister of the Environment (Minister) in March 2010.
As outlined in the Technical Work Plan in Appendix H of the approved Terms of Reference, this document is the third in a set of four stand-alone technical documents that will be produced during the UYSS EA. These documents are as follows:
Alternatives to the Undertaking: Technical Concept Document – this documentdescribes each Alternative To the Undertaking based on the Conceptual Designprepared.
Long List of Alternative Methods of Carrying out the Undertaking: TechnicalConcept Level 1 Document – describes the Concept Level 1 Designs. This documentwas used for reference purposes during the screening of the long list of AlternativeMethods of carrying out the Undertaking to arrive at a short list of Alternative Methods.
Short List of Alternative Methods of Carrying out the Undertaking: TechnicalConcept Level 2 Document (this document) – defines the Concept Level 2 Designs. Thisdocument will be used for reference purposes for assessing the short-listed Alternativemethods of carrying out the Undertaking.
Preliminary Design Report – will document the preliminary design of the preferredAlternative Method: This report will be used for reference purposes during theassessment of impacts associated with the preferred Alternative Method of carrying outthe Undertaking.
Technical Concept Level 1 Document was developed in accordance with Appendix H: Technical Work Plan to facilitate the screening of the long list to a short list of Alternative Methods through development of the Conceptual Design for the Water Reclamation Centre. It includes a description of the wastewater quantity and characteristics, as well as the quality requirements for treated effluent discharge and reuse. On this basis a conceptual treatment system was developed to enable the development of criteria to assist with screening the long list of potential Water Reclamation Sites to a short list. This also enabled the development of three alternative routes for the YDSS Modifications (see Section 2.0).
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Technical Concept Level 2 Document Upper York Sewage Solutions IEA
Technical Concept Level 2 Document provides engineering information regarding the selection process sizing and the layout and conveyance tailored to each of the short listed sites (see Section 3.0). The Carbon Dioxide Footprint for each site, in equivalent tonnes of carbon dioxide generated per year, is included as an indicator. The operation and maintenance strategy and constructability considerations are also described. Technical Concept Level 2 Document also provides engineering information regarding the plan, and profile and construction methodology for each of the three alternative YDSS Modifications (see Section 4.0). The alternatives are summarized in Section 5.0. This information will provide the technical basis for the comparison of the Alternative Methods for both the Water Reclamation Centre Site and the YDSS Modifications route to select the Preferred Alternative.
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Section 2.0 Description of the Short List of Alternative Water Reclamation Centre Sites and York Durham Sewage System Modifications Alternative Routes
2.1 Short List of Alternative Water Reclamation Centre Sites
The final screening criteria were applied to each of the 22 potential alternative Water Reclamation Centre sites via the updated GIS model. The outcome of applying the screening criteria was compared resulting in a short list of four alternative Water Reclamation Centre sites:
Site 24 Site 30 Site Willing Host 1 (WH1) Site Willing Host 2 (WH2)
These four alternative Water Reclamation Centre sites were selected to be carried forward for comparative evaluation because they all demonstrated advantages over the other potential alternative Water Reclamation Centre sites, thereby making them more suitable for accommodating the proposed Water Reclamation Centre while also minimizing potential adverse environmental effects (including natural, built, and economic environments).
Upon further evaluation of the sites, it was found that there were two suitable areas for the Water Reclamation Centre on Site WH1 and these were subsequently identified as Willing Host 1 West (WH1 W) and Willing Host 1 East (WH1 E). The locations of the five alternative sites are illustrated in Figure 2.1.
Site 24 is located at 20704 2nd Concession, on the west side of the road, approximately 400 m north of Queensville Sideroad in East Gwillimbury.
Site 30 is located at 20913 Leslie Street, on the east side of the street, approximately 500 m south of the intersection at Leslie Street and Holborn Road in East Gwillimbury.
Site WH1 West is located at 20908/20854 2nd Concession, on the east side of the road, approximately 1,000 m north of the intersection at 2nd Concession and Queensville Sideroad in East Gwillimbury.
Site WH1 East is located on the west side of Leslie Street, approximately 900 m south of the intersection at Leslie Street and Holborn Road in East Gwillimbury.
Site WH2 is located at 1004 Queensville Sideroad/20709-20733 2nd Concession, on the east side of 2nd Concession, approximately 800 m north of the intersection at 2nd Concession and Queensville Sideroad in East Gwillimbury.
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Technical Concept Level 2 Document Upper York Sewage Solutions IEA
The property plan for each of the alternative sites is provided in Figures 2.2 – 2.6. Following the selection of the short list of alternative Water Reclamation Centre sites, the infrastructure needed for conveying the collected wastewater to the facility for treatment and for conveying the treated effluent from the facility to a discharge location on the East Holland River was developed in further detail for each of the five short-listed sites.
East Holland River
Hydro C
orridor
WH2
WH1East
24
30
WH1West
Town ofEast Gwillimbury
Holborn Road
Queensville Sideroad
Woodbine Avenue
Doane Road
Mount Albert Road
Leslie Street
2nd Concession
Future Approved Bradford Bypass
UTM Zone 17N, NAD 83
Locations of WaterReclemation Centre
Alternative Sites
Figure 2.1Basemapping: Produced by CRA under license from RegionalMunicipality of York, and Ontario Ministry of Natural Resources,Land Information Ontario (LIO), 2011. © Queens Printer 2013
²500 0 500250 Meters
1:36,000This drawing has been prepared for the use of CRA's client and may not be used, reproduced or relied upon by third parties,except as agreed by CRA and its client, as required by law or for use by governmental reviewing agencies. CRA accepts no responsibility, and denies any liability whatsoever, to any partythat modifies this drawing without CRA's express written consent.
LegendUYSS Service AreaArea Suitable for Water Reclamation Centre Area Unsuitable for Water Reclamation Centre WatercourseWaterbodyMunicipal Division
! Hydro CorridorNote: Site WH2 includes site 42, formerly included in the Generation of the Long List of Potential Alternative Water Centre ReclamationCentre Sites
050278(REP081)GIS-WA007 January 31,2013
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Technical Concept Level 2 Document Upper York Sewage Solutions IEA
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Technical Concept Level 2 Document Upper York Sewage Solutions IEA
Figure 2.3: Site 30 Site Layout
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Technical Concept Level 2 Document Upper York Sewage Solutions IEA
Figure 2.4: WH1 West Site Layout
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Technical Concept Level 2 Document Upper York Sewage Solutions IEA
Figure 2.5: Site Willing Host 1 East
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Figure 2.6: Site WH2
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Technical Concept Level 2 Document Upper York Sewage Solutions IEA
2.2 YDSS Modifications Alternative Routes
The York-Durham Sewage System (YDSS) was constructed in the late 1970s and early 1980s, and originally served Vaughan, Markham, Richmond Hill, Aurora, and Newmarket. Modifications would be required to ensure that wastewater servicing remains reliable and secure to accommodate the approved growth for the Towns of Newmarket and Aurora to provide operational flexibility between integration of the existing YDSS and the proposed Water Reclamation Centre, and to provide forcemain back up to the existing Newmarket and Bogart Creek Pumping Station. Figure 2.7 presents the existing YDSS located in the UYSS service area.
The proposed modifications to the existing YDSS include the following:
A second forcemain (a new Newmarket forcemain) from the existing NewmarketPumping Station directly to the Aurora Pumping Station or to the existing gravity sewer,which discharges to the Aurora Pumping Station.
A second forcemain (a new Bogart Creek forcemain) from the existing Bogart CreekPumping Station to the new Newmarket forcemain.
Modifications to the Newmarket Pumping Station and Bogart Creek Pumping Station forconnection of the second forcemain.
Guiding principles were established to develop the proposed YDSS modifications. These guiding principles are:
Maximize the use of road/utility rights-of-ways and/or Regional or modifiable existingeasements, so that the need for private land acquisition is minimized or eliminated andconstruction would occur in previously developed areas.
Maximize the use of existing infrastructure to avoid the need for significant upgrades tothe existing Newmarket and Bogart Creek Pumping Station (minimize capital andoperating cost).
Based on the guiding principles, three alternative routes for additional wastewater conveyance from the existing Newmarket and Bogart Creek Pumping Station to the existing Aurora Pumping Station and existing YDSS were developed. The three routes are referred to as Alternative Route A, Alternative Route B, and Alternative Route C and are shown on Figure 2.8 and described in further detail in Section 4.
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Simcoe County
DurhamRegion
York Region
_̂
Duffin CreekWPCP
Town ofPickering
Town ofAjax
Township ofKing
City ofVaughan
Town ofMarkham
Town ofNewmarket
Town ofAurora
Town ofRichmond
Hill
Town ofWhitchurch-Stouffville
Town ofEast Gwillimbury
Lake Simcoe GeorginaIsland
FoxIsland
SnakeIsland
Town ofGeorgina
Keswick WPCP
Sutton WPCP
Mount Albert WPCPHolland LandingLagoons
SchombergLagoons
Kleinburg WPCP
AuroraPumping Station
LesliePumping Station
NewmarketPumping Station
High StreetPumping Station
Proctor RoadPumping Station
Mount AlbertPumping Station
Bogart CreekPumping Station
KeswickPumping Station No. 4
Woodriver BendPumping Station
Holland LandingPumping Station
South River RoadPumping Station
Schomberg Dr. KayPumping Station Schomberg Lagoon
Pumping Stations
Pine Valley SewagePumping Station
Georgina Regional SewagePumping Station No. 4
King City Sanitary ServicingRegional Pumping Station
UTM Zone 17N, NAD 83
Existing YDSSLocated in the
UYSS Area
GeorgianBay
LakeHuron
Lake Erie
Lake Ontario
YorkRegion
Basemapping: Produced by CRA under license from RegionalMunicipality of York, and Ontario Ministry of Natural Resources,Land Information Ontario (LIO), 2011. © Queens Printer 2011
²©2011 Conestoga-Rovers & Associates Ltd. All Rights Reserved. This document is protected by copyright law and may not be used, reproduced or modified in any manner or for any purpose exceptwith the written permission of Conestoga-Rovers & Associates Ltd. ("CRA") or a party to which itscopyright has been assigned. Conestoga-Rovers & Associates Ltd accepts no responsibility, and denies any liability whatsoever, to any party that uses, reproduces, modifies, or relies on thisdocument without Conestoga-Rovers & Associates Ltd. express written consent.
1:200,000
0 2 4 61 Kilometres
Legend! Existing YDSS Pumping Station & WPCP
Existing YDSS (Conveyance)!( York Region Satellite Pumping Station & WPCP (Lagoons)
York Region Satellite Sewage Conveyance SystemLower Tier MunicipalitiesUYSS Service AreaUYSS EA Study Area
Map Document: 050278(REP081)GIS-WA008 Thursday, January 31, 2013
Figure 2.7
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!
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Town ofNewmarket
Aurora Pumping Station
Newmarket Pumping Station
Bogart Creek Pumping Station
AB
C
CB
A
C
B'
B
C'
A'
LESL
IE ST
REET
YONG
E STR
EET
DAVIS DRIVE
MULOCK DRIVE
ST JOHN'S SIDEROAD
BAYV
IEW AV
ENUE
DAVIS DRIVE WEST
GREEN LANE EASTGREEN LANE WEST
2ND
CONC
ESSIO
NRO
AD
UTM Zone 17N, NAD 83 1:20,000
Alternative Route A,Alternative Route B, and
Alternative Route C
Figure 2.8
©2012 Conestoga-Rovers & Associates Ltd. All Rights Reserved. This document is protected by copyright law and may not be used, reproduced or modified in any manner or for any purpose exceptwith the written permission of Conestoga-Rovers & Associates Ltd. ("CRA") or a party to which itscopyright has been assigned. Conestoga-Rovers & Associates Ltd accepts no responsibility, and denies any liability whatsoever, to any party that uses, reproduces, modifies, or relies on thisdocument without Conestoga-Rovers & Associates Ltd. express written consent.
Basemapping: Produced by CRA under license from RegionalMunicipality of York, and Ontario Ministry of Natural Resources,Land Information Ontario (LIO), 2011. © Queens Printer 2012
0 500 1,000 1,500250Metres
²LegendConceptual Routes
Alternative AAlternative BAlternative CBogart Route
! Pumping StationExisting Gravity SewerExisting Forcemain (Pressurized Sewer)
River - IntermittentRiver - Single LineWetlandWaterbodySignificant WoodlandWetland, UnevaluatedForest
Map Document: 050278(REP081)GIS-WA009 January 31, 2013
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Technical Concept Level 2 Document Upper York Sewage Solutions IEA
Section 3.0 Description of the Lake Simcoe Water Reclamation Centre Concept Design
3.1 Design Overview
Technical Concept Level 1 Document described the concept for a Water Reclamation Centre which would treat 40 megalitres per day (MLD) of wastewater, on an annual average daily flow basis. The treated effluent produced at the Lake Simcoe Water Reclamation Centre would be provided for both discharge to the East Holland River and as reclaimed water for various end users, many of them irrigation-based. The Water Reclamation Centre would be designed with the ability to discharge 100 percent of its effluent to the Lake Simcoe watershed producing final effluent average Total Phosphorus concentrations in the range of 0.01 mg/L to 0.02 mg/L. The plant would be designed with the operational flexibility needed to provide reclaimed water suitable for its intended purpose for various end uses such as sod farm irrigation.
This would allow beneficial use of nutrients contained in the wastewater and reduce operating costs. Thus the Water Reclamation Centre would be designed to operate in two modes:
100% of the treated effluent for surface water discharge, or
10% to 75% of the flow for local irrigation, with the remainder for surface waterdischarge.
This treatment strategy requires a process featuring parallel treatment trains designed to meet two very different end use water quality objectives. The surface water treatment train must produce an effluent that has minimal nutrients and is beneficial to the Lake Simcoe watershed. Following preliminary treatment (screening and degritting), the surface water discharge treatment train would include:
Chemically enhanced primary treatment (for enhanced removal of solids andphosphorus),
A biological nitrification – denitrification process in bioreactors (which would removeorganics and nitrogen),
Filtration (to remove particles prior to Reverse Osmosis (RO),
RO,
Post-RO conditioning to ensure adequate dissolved oxygen and hardness to protectaquatic life, and
Disinfection.
The reclaimed water treatment train, in contrast, is a simpler treatment process designed to produce a nutrient-rich effluent, suitable for land application. Following preliminary treatment, the reclaimed water treatment train would include:
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Conventional primary treatment without chemical addition to leave soluble phosphorus for fertilization,
Activated sludge secondary treatment using a short solids retention time (or “sludge age”) to remove organics only and not ammonia which is a desirable fertilizer,
Filtration (to remove particles), and
Disinfection
The hydraulic design concept would require the plant operators to periodically set the amount of flow to be sent to the reclaimed water treatment train, based on the demand for reclaimed water. With the fraction of flow going to the reclaimed water train set, all other flow would be sent to the surface water treatment train. The preliminary and primary treatment systems would be designed to handle peak hour flows. Following primary treatment, flow balancing basins would be utilized to dampen peak hour flows to the tertiary filtration system to the level of peak day flows. The reverse osmosis system would be designed to treat maximum month flow levels to achieve 0.01 to 0.02 mg/L of phosphorus. When the Lake Simcoe Water Reclamation Centre approaches its 40 MLD rated capacity, the Total Phosphorus discharged would be approximately 100 kg/yr of new phosphorus in excess of the Lake Simcoe Phosphorus Reduction Strategy allocation. A project-specific phosphorus off-setting program would address this increase through a minimum of 2:1 reduction of other sources of phosphorus (minimum 200 kg Total Phosphorus removed from other sources, such as storm water ponds, in the Lake Simcoe watershed). Further detail on the design of the Water Reclamation Centre treatment processes is provided in Appendix A. 3.2 Process Flow Diagrams
The treatment processes have been grouped according to three categories, and are discussed in the following order:
Conventional Treatment (preliminary through secondary treatment), Figure 3.1
Advanced Treatment (tertiary and quaternary treatment, as well as disinfection), Figure 3.2
Solids Management (biosolids thickening, storage, processing and dewatering) Figure 3.3
The liquid stream treatment process trains for both the surface water discharge treatment train and the reclaimed water treatment train are shown in the two liquid stream process flow diagrams: the Conventional Treatment System and the Advanced Treatment System. The reverse osmosis (RO) process removes dissolved solids from the RO permeate stream to the point where it becomes a high quality or ultra pure water. However to naturalize this water for surface water discharge, three options have been identified to reintroduce dissolved solids
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into the RO permeate stream, as indicated on the Advanced Treatment System process flow diagram:
Option A: Treat the RO concentrate to remove phosphorus and recombine it with the RO permeate prior to discharge
Option B: Send the RO concentrate to the YDSS and post-condition the RO permeate using chemical addition
Option C: Send the RO concentrate to the YDSS and post-condition the RO permeate using permeate from the microfiltration/ ultrafiltration system.
The solids management flow diagram provided in Figure 3.3 shows four options for biosolids end use at the Lake Simcoe Water Reclamation Centre site. The biosolids processing options illustrated are:
Biosolids Option A: Sending biosolids via the YDSS to Duffin Creek WPCP for processing
Biosolids Option B: Trucking thickened biosolids to Duffin Creek WPCP for processing.
Biosolids Option C: Storing anaerobically digested liquid biosolids on site, followed by seasonal land application of the liquid biosolids, and
Biosolids Option D: Dewatering anaerobically digested sludge on site, followed by land application of the dewatered biosolids.
Therefore, the site layouts for the short-listed sites have been developed with provision for adopting any of these biosolids processing options.
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Figure 3.1: Conventional Treatment Process Flow Diagram
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Figure 3.2: Solids Management Process Flow Diagram
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3.3 Water Reclamation Centre Sizing and Layout Requirements
3.3.1 Water Reclamation Centre Facilities Sizing and Services
The concept level layout of the Water Reclamation Centre and projected height for buildings as well as process storage tanks, were developed from the conceptual process design using the following assumptions:
Where the treatment process concept was still considering more than one process or technology or approach for a treatment step, in general the alternative with the largest footprint was assumed for concept layout purposes in order to be conservative in assessing the potential impact of the facility. For example,
For odour control, layouts assumed biofilters, which are low profile but have a larger footprint than either biotowers or activated carbon units.
For biosolids processing, it was assumed that digesters and liquid storage and biosolids dewatering and truck loading would be provided on site in order to ensure adequate footprint.
For reverse osmosis treatment and reverse osmosis permeate conditioning, a liberal layout was selected based on relevant experience at similar facilities.
The size for these processes will be refined during the Preliminary Design stage.
A site would be re-graded as required to provide a relatively flat site for the proposed treatment facilities.
Raw wastewater would be pumped to the Water Reclamation Centre via force mains. Therefore, the conventional treatment processes would not require intermediate pumping of the main flows.
No significant storage of reclaimed water was assumed for the treatment facility site. It was assumed that if significant storage for treated effluent is required prior to reuse, such storage would be located off-site.
Sizing of the structures and buildings for which the design had not been developed at the Alternative Methods stage, were based on engineering experience, taking into consideration layouts at similar sized facilities in Canada and the United States.
In addition to the unit operations described in Section 3.1, a number of support buildings were considered for the purposes of the layout:
Administration Building: a demonstration and training centre, and an architectural feature of the Water Reclamation Centre. The building houses offices, laboratories, shower facilities and a control centre.
Maintenance Building: houses all related maintenance activities, workshop and part storage.
Electrical Substation
Emergency Generator Building: houses the standby power generator
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Chemical Feed Buildings: three Chemical Feed Buildings located throughout the Water Reclamation Centre which nominally support the conventional processes, advanced treatment processes (including reverse osmosis permeate post-conditioning chemicals) and solids processing.
Table 3.1 presents the concept design information for each unit operation used for the layout. Table 3.1: Water Reclamation Centre Site Layout Facility Sizing Building Name Diameter Length / Width Height
(m)
A Headworks and Septage Receiving
37 18 13
B Conventional Treatment Biofilter 40 10 3
C Solids Management Biofilter 40 10 2
D Rapid Mix/Flocculation Tanks(1) 8 40 2
E Primary Clarifiers(1) 42 40 1.5
F Flow Balancing Tanks(1) 40 20 1.5
G Bioreactors 137 12 1.5
H Secondary Clarifiers(1) 28 1
I Blower Building 37 12 12
J Filtration for Reclaimed Water 32 26 9
K Microfiltration / Ultrafiltration Building
45 30 12
L RO Building with UV disinfection 45 60 15
L1 RO Feed Tanks 18 7
M UV Building for Reclaimed water 18 26 9
M1 Chlorine Contact for Reclaimed Water
20 10 9
N Standby Power Building 30 18 11
O Fermentation and Thickening(1)
(dome cover) 9 3
O1 Primary Sludge Fermenters 10 20 3
P Waste Activated Sludge Thickening Building
24 18 13
R1 Primary Digesters(1) 19 12
R2 Secondary Digester(1) 19 15
S Biogas Flare 6 3 11
T Biosolids Holding Tanks (dome cover)
30 12
W Dewatering Building 18 36 21
X Maintenance Building 31 61 12
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Y1 Chemical Feed Building 1 10.5
Y2 Chemical Feed Building 2 10.5
Y3 Chemical Feed Building 3 30 9 10.5
Z Administration Building 31 61 12
AA Biosolids Truck Loading Building 18 15 12
BB Post Aeration(1) 4
CC Post Conditioning 18 36 16
DD Reclaimed Water Bulk Loading Station
12 12 4
Notes 1) Assume subsurface conditions will allow tank foundations to be up to 6m below grade 2) For buildings, the height provided is measured from grade level to top of HVAC equipment on top of roof 3) Biosolids holding tank base is 2-3m below grade. 4) For tanks covered by a dome, height is from grade to top of dome The layout for the Water Reclamation Centre must also consider the supply of a number of external utilities including electrical power, natural gas, telecommunications and potable water. On-site utilities would include emergency power generation and stormwater management. These utilities are described in Appendix A. 3.3.2 Site Layout Constraints and Objectives
At each of the five short-listed alternative Water Reclamation Centre sites, the concept layouts were developed by taking into consideration layout objectives and the constraints at each site. The following were the overall objectives and preferences for the layout:
General arrangement of liquid stream facilities to reflect process flow lines, to minimize piping runs and minimize the need for intermediate pumping
Truck loop around the site to facilitate flow of traffic
All sludge processing facilities located in one area of the site
Administrative building in visible location at front entrance to the site
Two access roads to the site, where possible
Good truck access to headworks, sludge hauling and chemical delivery areas.
Provide room for phased implementation and later expansion to meet future increased flow or treatment requirements beyond 2031 (subject to future approval)
Take advantage of natural terrain such as hills on the sites, to provide additional visual barrier
The constraints for the layout were:
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Property Line: No facilities constructed outside of the existing property line
Setbacks from nearby streams and designated environmentally sensitive areas: 120 metre setback from sensitive environmental areas such as streams; also, avoid encroaching on ravines or environmentally significant wetlands
Delineated flood plain areas: No facilities constructed in the designated flood plain
Utility hydropower rights of way: No facilities constructed under power line rights-of-way
Visual Buffer Zone setbacks from the site property lines: Administrative Building with architectural features appropriate for fronting on main road near the main site entrance, to facilitate public access. All other structures feature a visual setback from site property boundary.
Air Separation Zone setbacks from the property lines and nearest inhabited structures, from potential sources of odours: Potential odour-generating processes set back 150 metres from the property line.
Table 3.2 lists the facilities that have been identified as potential sources of odours. These facilities, which include the headworks area, primary treatment and all of the biosolids processing facilities, would have positive odour control and also would be located within the 150 metre Air Separation Zone located between the source and the property boundary. This buffer would provide additional mitigation in the event unexpected releases of offensive odours should occur. Table 3.2: Facilities Included within Air Separation Zone
Layout Designation Facility Description
A Headworks and Septage Receiving
E Primary Clarifiers
F Flow Balancing Tanks
O Gravity Thickeners
P Waste Activated Sludge Thickening Building
T Biosolids Holding Tanks
R1 Primary Digesters
R2 Secondary Digester
S Biogas Flare
W Dewatering Building
AA Sludge Truck Loading Building
G Bioreactors (where possible)
H Secondary Clarifiers (where possible)
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Since the bioreactors are aerated treatment processes, it is not anticipated that the secondary treatment facilities (bioreactors and secondary clarifiers) would be considered a source of potential odours. As a result, no allowance was made for a process to treat air from the bioreactors (aeration basins) or secondary clarifiers. However, it is considered advantageous to locate these units within the odour control buffer zone where practical. This preference is noted on Table 3.2, and was incorporated into the site layouts where feasible. Since none of the facilities in the advanced treatment section of the facility has the potential to generate wastewater odours, it would not be necessary to include those facilities within the 150 metre buffer zone. 3.3.3 Wastewater Conveyance to Water Reclamation Centre
The Queensville Holland Landing Sharon Wastewater Infrastructure Class EA Review and Addendum completed in 2007 proposed the interim construction of a system to receive wastewater from the communities of Queensville, Holland Landing and Sharon within the Town of East Gwillimbury and convey it to the YDSS at the Newmarket Pumping Station. The system was recommended to meet planning needs in the short term before implementation of the long-term solution for wastewater servicing in upper York, to be determined by the UYSS EA. The interim solution, referred to as the “Queensville Holland Landing Sharon (QHLS) Wastewater Servicing Project,” is currently underway. The QHLS Wastewater Servicing project includes gravity sewers, forcemains, and three new pumping stations: Holland Landing, 2nd Concession, and Queensville West Pumping Stations. This infrastructure will convey wastewater to the YDSS at the Newmarket Pumping Station and would ultimately be used to convey wastewater to the Water Reclamation Centre. The locations of the sewage pumping stations and associated linear infrastructure are shown on Figure 3.4 in relation to the short list of alternative Water Reclamation Centre sites. The Queensville Holland Landing Sharon (QHLS) Wastewater Servicing project will operate until the long-term solution for wastewater servicing in upper York is determined by the UYSS EA, approved by the Minister of the Environment, and built by York Region, as follows:
From the Queensville West Pumping Station, wastewater will be conveyed via forcemain to a gravity sewer on 2nd Concession that will drain to the 2nd Concession Pump Station.
Wastewater from the Holland Landing Pumping Station will also be conveyed via forcemain to the gravity sewer on 2nd Concession that will drain to the 2nd Concession Pump Station.
Wastewater from the Sharon community will be conveyed to the 2nd Concession Pumping Station via gravity sewer.
Wastewater from the Green Lane Trunk Sewer (includes northwest portion of Newmarket) will be conveyed to the 2nd Concession Pumping Station via gravity sewer.
Wastewater from the 2nd Concession Pumping Station (including wastewater from the Holland Landing and Queensville West Pumping Stations, Sharon gravity sewer, and
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from the Green Lane Trunk Sewer) will be conveyed via forcemain to the Newmarket Pumping Station.
Construction of the QHLS Wastewater Servicing project will also include installation of twin forcemains from the 2nd Concession Pumping Station terminating near the Queensville West Pumping Station along 2nd Concession in anticipation of a potential future connection to the proposed Water Reclamation Centre. Upon commissioning of the Water Reclamation Centre wastewater would be routed as follows, as illustrated in Figure 3.5:
Wastewater generated in the communities of Queensville, and Sharon would be conveyed to the Queensville West and 2nd Concession Pumping Stations, respectively.
Wastewater from the northwest portion of the Town of Newmarket would be conveyed to the 2nd Concession Pumping Station following redirection of the existing Green Lane Trunk Sewer (which currently conveys wastewater to the Newmarket Pumping Station).
The wastewater forcemains from the Holland Landing Pumping Station would connect into the 2nd Concession Pumping Station forcemains.
The Queensville West Pumping Station and the Second Concession Pumping Station would pump wastewater to the Water Reclamation Centre. Both forcemains would be twinned for redundancy so that there would be four forcemains feeding the facility.
A future Queensville East Pumping Station is anticipated.
")
")
")
")
WH2
WH1East
24
30
WH1West
2nd ConcessionPumping Station
Holland LandingPumping Station
Queensville WestPumping Station
Town ofEast Gwillimbury
Town ofNewmarket
Townshipof King
Hwy 404
Holborn Road
Queensville Sideroad
Woodbine Avenue
Doane Road
Mount Albert Road
Leslie Street
2nd Concession
Holland Landing Road
Bathurst Street
Yonge Street
Green Lane
Herald Road
UTM Zone 17N, NAD 83
Locations of WaterReclamation Centre Alternive
Sites and the Queensville,Holland Landing, Sharon,
Wastewater Servicing Project
Figure 3.4Basemapping: Produced by CRA under license from RegionalMunicipality of York, and Ontario Ministry of Natural Resources,Land Information Ontario (LIO), 2011. © Queens Printer 2012
²500 0 500250 Meters
1:50,000
This drawing has been prepared for the use of CRA's client and may not be used, reproduced or relied upon by third parties,except as agreed by CRA and its client, as required by law or for use by governmental reviewing agencies. CRA accepts no responsibility, and denies any liability whatsoever, to any partythat modifies this drawing without CRA's express written consent.
LegendUYSS Service Area
") Existing Pumping Station
")Queensville HollandLanding Sharon WastewaterServicing System - Pumping StationQueensville HollandLanding Sharon WastewaterServicing System - InfrastructureExisting Approved Holland LandingLagoon Water Pollution Control Plant
Area Suitable for Water Reclamation Centre Area Unsuitable for Water Reclamation Centre Oak Ridges Moraine BoundaryWatercourseWaterbodyProposed RoadMunicipal Division
Note: Site WH2 includes site 42, formerly included in the Generation of the Long List of Potential Alternative Water Centre ReclamationCentre Sites
050278(REP081)GIS-WA001_Routes January 31,2013
")
")
")
")
WH2
WH1East
24
30
WH1West
2nd ConcessionPumping Station
Holland LandingPumping Station
Queensville WestPumping Station
Town ofEast Gwillimbury
Town ofNewmarket
Townshipof King
Hwy 404
Holborn Road
Queensville Sideroad
Woodbine Avenue
Doane Road
Mount Albert Road
Leslie Street
2nd Concession
Holland Landing Road
Bathurst Street
Yonge Street
Green Lane
Herald Road
UTM Zone 17N, NAD 83
Queensville,Holland Landing,Sharon, and North-WestNewmarket WastewaterServicing Strategy upon
Construction of theWater Reclamation Centre
Figure 3.5Basemapping: Produced by CRA under license from RegionalMunicipality of York, and Ontario Ministry of Natural Resources,Land Information Ontario (LIO), 2011. © Queens Printer 2012
²500 0 500250 Meters
1:50,000
This drawing has been prepared for the use of CRA's client and may not be used, reproduced or relied upon by third parties,except as agreed by CRA and its client, as required by law or for use by governmental reviewing agencies. CRA accepts no responsibility, and denies any liability whatsoever, to any partythat modifies this drawing without CRA's express written consent.
LegendUYSS Service Area
") Existing Pumping Station
")Queensville HollandLanding Sharon WastewaterServicing System - Pumping StationQueensville HollandLanding Sharon WastewaterServicing System - InfrastructureExisting Approved Holland LandingLagoon Water Pollution Control Plant
Area Suitable for Water Reclamation Centre Area Unsuitable for Water Reclamation Centre Oak Ridges Moraine BoundaryWatercourseWaterbodyProposed RoadMunicipal Division
Note: Site WH2 includes site 42, formerly included in the Generation of the Long List of Potential Alternative Water Centre ReclamationCentre Sites
050278(REP081)GIS-WA010 January 31,2013
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For each of the short-listed Water Reclamation Centre sites, a conceptual conveyance system was developed for delivery of wastewater to the site. Guiding principles for the development of the conveyance concepts were:
Maximize use of existing road/utility rights-of-way and/or Regional easements, thereby minimizing required land acquisition and utilizing developed areas
Minimize potential effects to the social and natural environments (for example, traffic disruptions during construction, effects on wetlands, tree removal)
Minimize forcemain length, depth below ground surface, and pumping requirements (energy requirements)
Optimize use of existing grades in selection of the type of main (i.e., forcemain vs. gravity sewer)
The concepts for conveyance of wastewater to each of the short-listed Water Reclamation Centre sites are described in detail in Section 3.4. 3.3.4 Treated Effluent Outfall from the Water Reclamation Centre
In addition to infrastructure for conveyance of wastewater to the Water Reclamation Centre, infrastructure is required to convey treated effluent from the proposed Water Reclamation Centre for discharge. Guiding principles used in the identification of potential discharge locations and the development of conceptual conveyance systems for delivery of treated effluent from each of the alternative Water Reclamation Centre sites included those listed above for conveyance to the alternative Water Reclamation Centre Site, as well as:
Maximize positive impact of discharge (water quality and quantity improvements)
Discharge to Cook’s Bay was less desirable than discharge to the East Holland River because the distance to Cook’s Bay from all of the alternative Water Reclamation Centre sites was considerably greater than the distance from the sites to the East Holland River resulting in greater cost and affected area. Discharge to the East Holland River also maximizes the positive impact of the discharge (increased river flow, reduced phosphorus concentrations, decreased water temperature in summer months and increased water clarity), which decreases considerably beyond the confluence of the East Holland River with the West Holland River. Positive impacts to the East Holland River improve with distance upstream from the East and West Holland River confluence. The concepts for conveyance of treated effluent from each of the short-listed Water Reclamation Centre sites to a potential discharge location in the East Holland River at Queensville Sideroad are described in detail in Section 3.3.
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3.3.5 Carbon Footprint
The Technical Workplan (Appendix H) of the Approved Terms of Reference identifies carbon dioxide footprint as the preliminary evaluation criterion to compare Alternative Methods, with the Equivalent tonnes of Carbon Dioxide per year (CO2e/yr) as the Indicator for this criterion. An overall operational carbon footprint was developed for the Lake Simcoe Water Reclamation Centre to determine the impact from the proposed process facilities. The carbon footprint associated with the conveyance to each site (each Alternative Method) was also calculated. The combination of the operational carbon footprint plus the associated conveyance resulted in the total carbon footprint for each Alternative site. The CO2e generated indicator was evaluated on direct emissions, indirect emissions and equivalent electricity. Direct emissions can include burning of natural gas, vehicle transport emissions, process equipment emissions, chemical usage emissions, biosolids/residuals transportation emissions and off-site biosolids/residuals decomposition emissions. Indirect emissions can include operating staff commuting and biogas. The emissions directly applicable to the Water Reclamation Centre are discussed further in Appendix G. For the determination of the carbon footprint, the surface water discharge operating mode was used (i.e. no reclaimed water for irrigation; all discharge to the East Holland River). This is a worst case scenario for the carbon footprint. Without beneficial reuse of the biosolids, the carbon footprint for the Water Reclamation Centre is approximately 2,7801 tonnes CO2e/yr. Initially, solids from the facility will be pumped to the Duffin Creek Water Pollution Control Plant as on-site processing is not attractive at the lower startup flows. On-site processing of biosolids is anticipated to be constructed prior to 2031. The carbon footprint for the operation of the Water Reclamation Centre is reduced to 1,880 tonnes CO2e/yr, the value noted above, when the solids are anaerobically digested, dewatered and land applied capturing the carbon and utilizing the nutrients. To be conservative in the assessment, the higher value (without on-site solid processing) was reported for the comparative evaluation of the alternatives. Carbon footprint for the Water Reclamation Centre and related conveyance for each site is further described in Section 3.4
1 *As the result of further analysis and refinement, the value of approximately 2,780 tonnes CO2e/year has been estimated for the Water Reclamation Centre without on-site solids processing (previously reported as approximately 2,580 tonnes CO2e/year). As the carbon footprint is the same for all alternative sites, this value had no bearing on the comparative evaluation.
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3.4 Alternative Water Reclamation Centre Site Layouts
3.4.1 Site 24
3.4.1.1 Site 24 Facility Layout
The layout for Alternative Water Reclamation Centre Site 24 is shown in Figure 3.6
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Figure 3.6: Site 24 Water Reclamation Centre Site Layout
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3.4.1.2 Site 24 Geotechnical Assessment and Structural Design
Site 24 could not be accessed for a preliminary geotechnical investigation because the landowner’s permission could not be obtained. As the location of this site is just west of sites WH1 and WH2, it can be assumed that the subsurface conditions and structural considerations at Site 24 would likely be similar to WH2 and WH1 West (see Section 3.4.3.2 and Appendix C – Geotechnical Report). 3.4.1.3 Conveyance Infrastructure To/From Site 24
Figure 3.7 shows the location of Site 24 and associated wastewater and treated effluent conveyance infrastructure routes. Appendix D contains the plan and profile figures for the conveyance infrastructure routes from the location of the proposed Queensville West Pumping Station to Site 24 and from the site to the potential discharge location in the East Holland River at Queensville Side Road. The route for the RO concentrate forcemain is also shown. Wastewater collected from the QHLS Wastewater Servicing System would be conveyed to Site 24 along 2nd Concession via the following forcemains:
Twin forcemains, each with an approximate diameter of 600 mm, from the Queensville West Pumping Station.
Twin forcemains, each with an approximate diameter of 750 mm, from the 2nd Concession Pumping Station. The forcemains from the 2nd Concession Pumping Station to a point at the Queensville West Pumping Station are part of the QHLS Wastewater Servicing project. From this end point, the twin forcemains would be extended to the proposed Water Reclamation Centre as part of the UYSS EA.
Twin forcemains from a future Queensville East Pumping Station
From the Queensville West Pumping Station, the distance along 2nd Concession to Site 24 is approximately 1 km. The new conveyance infrastructure would be constructed primarily using conventional open-cut methods and would all be constructed within the existing 2nd Concession right-of-way. From Site 24, the RO concentrate forcemain line travels a distance of approximately 7.2km along 2nd Concession and Green Lane East to the Newmarket Pumping Station. The new conveyance infrastructure would be constructed primarily using conventional open-cut methods and would all be built within the existing 2nd Concession, and Green Lane East rights-of-way. For watercourse crossings, alternative construction methods such as jacking and boring or directional drilling may be required. A gravity outfall pipe, approximately 1200 mm in diameter, would be constructed from Site 24 along the 2nd Concession and the Queensville Sideroad road rights-of-way to the East Holland River. The gravity outfall pipe would be approximately 2.8 km long and constructed primarily using conventional open-cut methods. For watercourse crossings, alternative construction methods such as jacking and boring or directional drilling may be required.
")
")
_̂
WH2
WH1West
WH1East
2nd ConcessionPumping Station
Holland LandingPumping Station
Queensville WestPumping Station
Town ofEast Gwillimbury
Holborn Road
Queensville Sideroad
Woodbine Avenue
Doane Road
Mount Albert Road
Leslie Street
2nd Concession
Holland Landing Road
Bathurst Street
24
30
Hwy 11Yonge Street
UTM Zone 17N, NAD 83
Site 24 Water ReclamationCentre and Associated
Conveyance InfrastructureRoutes
Figure 3.7Basemapping: Produced by CRA under license from RegionalMunicipality of York, and Ontario Ministry of Natural Resources,Land Information Ontario (LIO), 2011. © Queens Printer 2013
²500 0 500250 Meters
1:40,000
This drawing has been prepared for the use of CRA's client and may not be used, reproduced or relied upon by third parties,except as agreed by CRA and its client, as required by law or for use by governmental reviewing agencies. CRA accepts no responsibility, and denies any liability whatsoever, to any partythat modifies this drawing without CRA's express written consent.
LegendUYSS Service AreaProposed Route to OutfallProposed Route fromQueensville West Pumping StationProposed Route from2nd Concession Pumping Station
_̂ Proposed Outfall
")Queensville HollandLanding Sharon WastewaterServicing System - Pumping StationQueensville HollandLanding Sharon WastewaterServicing System - Infrastructure
Existing Approved Holland LandingLagoon Water Pollution Control Plant Area Suitable for Water Reclamation Centre Area Unsuitable for Water Reclamation Centre Oak Ridges Moraine BoundaryWatercourseWaterbodyProposed RoadMunicipal Division
050278(REP081)GIS-WA002_Site24 January 31,2013
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3.4.1.4 Site 24 Servicing and Access
Hydro One does not currently have a 44kV service on 2nd Concession adjacent to Site 24. The closest 44 kV service is located on 2nd Concession but only as far north as Queensville Side Road. As such, the electrical overhead power line would need to be extended approximately 1,000 metres to service a Water Reclamation Centre at Site 24. The utility provider for natural gas in this area is Enbridge. Enbridge has advised that the closest supply of natural gas available is on 2nd Concession but only as far north as Algonquin Forest Drive. As such, the natural gas service would need to be extended approximately 1,850 metres.. Bell has pole mounted lines on 2nd Concession between Queensville Side Road and Holborn Road and has advised that they can provide phone (voice/fax) and DSL internet service to Site 24. The Town of East Gwillimbury does not currently have watermains in the area of Site 24. However, as part of the QHLS Wastewater Servicing project a new York Region distribution watermain is planned to be installed along 2nd Concession. This line would need to be extended approximately 1,850 metres to provide a water connection at Site 24. Access to Site 24 would be provided by two entrances from 2nd Concession. The south entrance would provide direct access to the employee and visitor parking lot at the Administration Building, while the north entrance would be used as the service entrance, and would provide service vehicles with access to the on-site road network. The on-site road network includes two branches: the north branch would provide service vehicles with access to the Maintenance Building, and the south branch would provide service vehicles with access to the Digester Complex and truck loading area for biosolids. Since the on-site access road is not looped, each branch of the road would need to be designed to allow service vehicles to turn around at the dead ends. North of Queensville Side Road, 2nd Concession is a local two lane roadway servicing the homes and farms on 2nd Concession. For the Water Reclamation Centre to be located at Site 24 approximately 500 metres of 2nd Concession would have to be upgraded to accommodate the larger service vehicles. Upgrading of the roadway would be incorporated with the construction of the conveyance infrastructure to the Water Reclamation Centre and Outfall from the Water Reclamation Centre which is also located within the 2nd Concession right-of-way. Queensville Side Road is a major east-west York Region transportation corridor that can accommodate the vehicle traffic associated with the Water Reclamation Centre. 3.4.1.5 Site 24 Carbon Footprint
As described in Section 3.3.5, the carbon footprint was calculated as an indicator for each of the Alternatives. The carbon footprint for Site 24 is shown in Table 3.3.
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Table 3.3: Carbon Footprint for Water Reclamation Centre Site 24
Equivalent CO2 generated in tones CO2e per year Conveyance To Approximately 149 tonnes CO2e/yr Conveyance From Approximately 54 tonnes CO2e/yr
Total Conveyance
Approximately 203 tonnes CO2e/yr
Facility Approximately 2,780 tonnes CO2e/yr
Total for Site 24 Approximately 2,983 tonnes CO2e/yr 3.4.2 Site 30
3.4.2.1 Site 30 Facility Layout
The layout for Alternative Water Reclamation Centre Site 30 is shown in Figure 3.8.
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Figure 3.8: Site 30 Water Reclamation Centre Site Layout
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3.4.2.2 Site 30 Geotechnical Assessment and Structural Design
To assess the geotechnical conditions at Site 30 six boreholes were drilled generally to depths of 12 to 15 metres. Each borehole encountered granular deposits of silt, sandy silt, silty sand and sand, in compact to very dense condition, starting at a depth of around 1.2 to 2.3 metres. Fine-grained silty clay to clayey silt and till deposits having stiff to hard consistency were also encountered at some borehole locations. Field Standard Penetration Test ‘N’ values are typically quite high ranging from 20 to in excess of 50 blows per 30 mm throughout the boreholes. Groundwater levels measured in monitoring wells installed at three of the boreholes were 4.7 to 4.8 metres below local ground level. Appendix C contains the geotechnical investigation report for the three Water Reclamation Centre sites for which access was provided. There are no anticipated unusual foundation issues for this site. Expected Serviceability Limit States and Ultimate Limit States bearing capacities will be sufficiently high (200 to 500 kPa at Serviceability Limit States and 300 to 750 kPa at Ultimate Limit States) to allow conventional strip/spread footings below buildings and reinforced floor slabs to support in-ground and above grade tank structures. All foundations would be founded below frost depth or otherwise protected from frost, and typical checks for buoyant effects on the in-ground tanks would need to be made. Fill materials, generally around 1.5 metres deep but to a maximum of 2.3 metres, would also need to be removed so that footings may be founded on native subgrade. The topography at Site 30 has been noted as undulating with a maximum grade difference between borehole locations in the order of 19.9 metres. This would likely require significant cuts and fills across the site and possibly earth retaining structures along site roads or adjacent to structures. Foundations for structures constructed on properly placed and compacted engineered fill within cut areas would be designed for lower bearing capacities, in the order of 150 kPa for Serviceability Limit States design and 225 kPa for Ultimate Limit States design. 3.4.2.3 Conveyance Infrastructure To/From Site 30
Alternative Site 30 is located on the east side of Leslie Street north of Queensville Sideroad and south of Holborn Road. Figure 3.9 shows the location of alternative Water Reclamation Centre Site 30 and associated wastewater and treated effluent conveyance infrastructure routes. Appendix D contains the plan and profile figures for the conveyance infrastructure routes from the location of the proposed Queensville West Pumping Station to Site 30 and from the site to a potential discharge location in the East Holland River at Queensville Side Road. The route for the RO concentrate forcemain is also shown. Wastewater collected from the QHLS Wastewater Servicing System would be conveyed to Site 30 along 2nd Concession, Holborn Road and Leslie Street via the following forcemains:
Twin forcemains, each with an approximate diameter of 600 mm, from the Queensville West Pumping Station.
Twin forcemains, each with an approximate diameter of 750 mm, from the 2nd Concession Pumping Station. The forcemains from the 2nd Concession Pumping
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Station to a point at the Queensville West Pumping Station are part of the QHLS Wastewater Servicing project. From this end point, the twin forcemains would be extended to the proposed Water Reclamation Centre as part of the UYSS EA.
Twin forcemains from a future Queensville East Pumping Station
From the Queensville West Pumping Station, the distance along 2nd Concession, Holborn Road and Leslie Street is approximately 5.5 km. The new conveyance infrastructure would be constructed primarily using conventional open-cut methods and would all be built within the existing 2nd Concession, Holborn Road, and Leslie Street rights-of-way. This route is slightly longer than an alternative going east on Queensville Side Road and north on Leslie Street, but avoids an area of higher elevation on Leslie Street that would result in increased operating cost due to pumping. From Site 30, the RO concentrate forcemain travels a distance of approximately 12.1km along Leslie Street, Holborn Road, 2nd Concession and Green Lane East to the Newmarket Pumping Station. The new conveyance infrastructure would be constructed primarily using conventional open-cut methods and would all be built within the existing Leslie Street, Holborn Road, 2nd Concession, and Green Lane East rights-of-way. For watercourse crossings, alternative construction methods such as jacking and boring or directional drilling may be required. This route is slightly longer than an alternative going east on Queensville Side Road and north on Leslie Street, but avoids an area of higher elevation on Leslie Street that would result in increased operating cost due to pumping. A gravity outfall pipe, approximately 1200 mm in diameter, would be constructed from Site 30 north along Leslie Street, west along Holborn Road, south along 2nd Concession, and west along Queensville Sideroad (all within the road rights-of-way) to the East Holland River. The gravity outfall pipe would be approximately 7.5 km long and constructed primarily using conventional open-cut methods. For watercourse crossings, alternative construction methods such as jacking and boring or directional drilling may be required.
")
")
_̂
WH2
WH1West
WH1East
2nd ConcessionPumping Station
Holland LandingPumping Station
Queensville WestPumping Station
Town ofEast Gwillimbury
Holborn Road
Queensville Sideroad
Woodbine Avenue
Doane Road
Mount Albert Road
Leslie Street
2nd Concession
Holland Landing Road
Bathurst Street
24
30
Hwy 11Yonge Street
UTM Zone 17N, NAD 83
Site 30 Water ReclamationCentre and Associated
Conveyance InfrastructureRoutes
Figure 3.9Basemapping: Produced by CRA under license from RegionalMunicipality of York, and Ontario Ministry of Natural Resources,Land Information Ontario (LIO), 2011. © Queens Printer 2012
²500 0 500250 Meters
1:40,000
This drawing has been prepared for the use of CRA's client and may not be used, reproduced or relied upon by third parties,except as agreed by CRA and its client, as required by law or for use by governmental reviewing agencies. CRA accepts no responsibility, and denies any liability whatsoever, to any partythat modifies this drawing without CRA's express written consent.
LegendUYSS Service AreaProposed Route to OutfallProposed Route fromQueensville West Pumping StationProposed Route from2nd Concession Pumping Station
_̂ Proposed Outfall
")Queensville HollandLanding Sharon WastewaterServicing System - Pumping StationQueensville HollandLanding Sharon WastewaterServicing System - Infrastructure
Existing Approved Holland LandingLagoon Water Pollution Control Plant Area Suitable for Water Reclamation Centre Area Unsuitable for Water Reclamation Centre Oak Ridges Moraine BoundaryWatercourseWaterbodyProposed RoadMunicipal Division
050278(REP081)GIS-WA003_Site30 January 31,2013
050278 (81) York Region No. 74270 Page 43
Technical Concept Level 2 Document Upper York Sewage Solutions IEA
3.4.2.4 Site 30 Servicing and Access
Hydro One currently has a 44kV overhead power line on Leslie Street adjacent to Site 30. This line can be used to provide power to the Water Reclamation Centre at Site 30. The utility provider for natural gas in this area is Enbridge. Enbridge has an existing natural gas main along Leslie Street passing Site 30 that could be used to supply the Water Reclamation Centre. Bell has buried lines along Leslie Street passing Site 30 and has advised that they can provide phone (voice/fax) and DSL internet service to this site. The Town of East Gwillimbury has an existing 250 mm diameter potable water watermain on Leslie Street but only for 800 metres north of Queensville Side Road (terminating opposite the Cemetery). To provide potable water service to Site 30, this watermain would need to be extended approximately 300 metres. Access to Site 30 would be provided by one entrance from Leslie Street, which would result in all vehicles that visit the Site entering and exiting at the same location. The entrance would provide direct access to the employee and visitor parking lot at the Administration Building. Driving past the Administration Building, service vehicles would have access to the on-site access road network. The on-site access road network includes two loops, which would provide service vehicles with access to all Site buildings. Leslie Street is a major north-south York Region transportation corridor that can accommodate the vehicle traffic associated with the Water Reclamation Centre. The location on the site of the single entrance would be a suitable distance from the top of the hill on Leslie Street to have visual line of sight for safe access from the Water Reclamation Centre onto Leslie Street. 3.4.2.5 Site 30 Carbon Footprint
As described in Section 3.3.5, the carbon footprint was calculated as an indicator for each of the Alternatives. The carbon footprint for Site 30 is shown in Table 3.4. Table 3.4: Carbon Footprint for Water Reclamation Centre Site 30
Equivalent CO2 generated in tones CO2e per year Conveyance To Approximately 188 tonnes CO2e/yr Conveyance From Approximately 40 tonnes CO2e/yr Total Conveyance
Approximately 228 tonnes CO2e/yr
Facility Approximately 2,780 tonnes CO2e/yr Total for Site 30 Approximately 3,008 tonnes CO2e/yr
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3.4.3 WH1 West
3.4.3.1 Site WH1 West Facility Layout
WH1 West Water Reclamation Centre Site Layout is shown in Figure 3.10
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Figure 3.10: WH1 West Water Reclamation Centre Site Layout
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Technical Concept Level 2 Document Upper York Sewage Solutions IEA
3.4.3.2 Site WH1 West Geotechnical Assessment and Structural Design
To access the geotechnical conditions at WH1 West four boreholes were drilled on the west side of the WH1 site, each to a depth of approximately 20 metres. Each borehole encountered fill deposits extending to depths of around 1 to 2.3 metres. The fill is overlying native clayey silt to sandy silt, generally in compact or stiff to very stiff condition and extending to a depth of 15 to 17 metres (9.3 metres at Borehole WH1-4). A layer of silty sand in a very loose to very dense condition was encountered below the above-noted material to a depth of about 18.3 metres in Borehole WH1-2 and to the termination depth at Borehole WH1-3. Deposits of silty clay with very soft to firm consistency are present at Borehole WH1-1 from approximately 16.7 metres to the termination depth of the borehole. In Boreholes WH1-1, WH1-2 and WH1-3, lower field Standard Penetration Test ‘N’ values were also noted at the top of the sandy silt deposit at a depth of approximately 6.0 metres. The loose material was not encountered at Borehole WH1-4 but rather the underlying material consisted of glacial deposits of sandy silt till in compact to very dense condition overlying hard silty clay till. Appendix C contains the geotechnical investigation report for the three Water Reclamation Centre sites for which access was provided. Measured groundwater elevations in monitoring wells installed in three of the boreholes range between 2 and 3 metres belowground surface (after around three weeks following drilling). The site for the Water Reclamation Centre is relatively flat and is only above the East Holland River flood line elevation by 1 to 2 metres. Therefore in an extreme flood event the groundwater elevation would be at grade and this should be used for design of structures at this site. In areas where loose material was encountered at a depth of around 6 metres (north and west half of the site), this material may need to be removed and replaced with engineered fill below the structure foundations. The second loose or very soft subgrade material at the greater depth of 15 to 20 metres could also have an effect on the foundation designs. If WH1-West is the preferred site for the Water Reclamation Centre then additional deeper boreholes will be required to evaluate this site further. Depending on the findings, deep foundations may be required to support structures at some of the locations on the site. Deep foundations would consist of cast-in-place concrete caissons or driven steel piles, founded at depth below the soft subgrade layers. 3.4.2.3 Conveyance Infrastructure To/From Site WH1 West
Alternative Site WH 1 West is located on 2nd Concession north of Queensville Sideroad and south of Holborn Road. Figure 3.11 shows the location of alternative Water Reclamation Centre Site WH 1 West and associated wastewater and treated effluent conveyance infrastructure routes. Appendix D contains the plan and profile figures for the conveyance infrastructure routes from the location of the proposed Queensville West Pumping Station to Site WH 1 West and from the site to a potential discharge location in the East Holland River at Queensville Side Road. The route for the RO concentrate forcemain is also shown.
")
")
_̂
WH2
WH1West
WH1East
2nd ConcessionPumping Station
Holland LandingPumping Station
Queensville WestPumping Station
Town ofEast Gwillimbury
Holborn Road
Queensville Sideroad
Woodbine Avenue
Doane Road
Mount Albert Road
Leslie Street
2nd Concession
Holland Landing Road
Bathurst Street
24
30
Hwy 11Yonge Street
UTM Zone 17N, NAD 83
WH1-West Water ReclamationCentre and Associated
Conveyance InfrastructureRoutes
Figure 3.11Basemapping: Produced by CRA under license from RegionalMunicipality of York, and Ontario Ministry of Natural Resources,Land Information Ontario (LIO), 2011. © Queens Printer 2012
²500 0 500250 Meters
1:40,000
This drawing has been prepared for the use of CRA's client and may not be used, reproduced or relied upon by third parties,except as agreed by CRA and its client, as required by law or for use by governmental reviewing agencies. CRA accepts no responsibility, and denies any liability whatsoever, to any partythat modifies this drawing without CRA's express written consent.
LegendUYSS Service AreaProposed Route to OutfallProposed Route fromQueensville West Pumping StationProposed Route from2nd Concession Pumping Station
_̂ Proposed Outfall
")Queensville HollandLanding Sharon WastewaterServicing System - Pumping StationQueensville HollandLanding Sharon WastewaterServicing System - Infrastructure
Existing Approved Holland LandingLagoon Water Pollution Control Plant Area Suitable for Water Reclamation Centre Area Unsuitable for Water Reclamation Centre Oak Ridges Moraine BoundaryWatercourseWaterbodyProposed RoadMunicipal Division
050278(REP081)GIS-WA004_WH1-West January 31,2013
050278 (81) York Region No. 74270 Page 48
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Wastewater collected from the QHLS Wastewater Servicing System would be conveyed to Site WH 1 West along 2nd Concession via the following forcemains:
Twin forcemains, each with an approximate diameter of 600 mm, from the Queensville West Pumping Station.
Twin forcemains, each with an approximate diameter of 750 mm, from the 2nd Concession Pumping Station. The forcemains from the 2nd Concession Pumping Station to a point at the Queensville West Pumping Station are part of the QHLS Wastewater Servicing project. From this end point, the twin forcemains would be extended to the proposed Water Reclamation Centre as part of the UYSS EA.
Twin forcemains from a future Queensville East Pumping Station
From the Queensville West Pumping Station, the distance along 2nd Concession is approximately 1.5 km. The new conveyance infrastructure would be constructed primarily using conventional open-cut methods and would all be built within the existing 2nd Concession right-of-way. From Site WH1 West, the RO concentrate forcemain travels a distance of approximately 7.2km along 2nd Concession and Green Lane East to the Newmarket Pumping Station. The new conveyance infrastructure would be constructed primarily using conventional open-cut methods and would all be built within the existing 2nd Concession, and Green Lane East rights-of-way. For watercourse crossings, alternative construction methods such as jacking and boring or directional drilling may be required. A gravity outfall pipe, approximately 1200 mm in diameter, would be constructed from Site WH 1 West along the 2nd Concession and Queensville Sideroad road rights-of-way to the East Holland River. The gravity outfall pipe would be approximately 3.5 km long and constructed primarily using conventional open-cut methods. For watercourse crossings, alternative construction methods such as jacking and boring or directional drilling may be required. 3.4.3.4 Site WH1 West Servicing and Access
Hydro One does not currently have a 44kV service on 2nd Concession adjacent to WH1-West. The closest 44 kV service is located on 2nd Concession but only as far north as Queensville Side Road. As such, the electrical overhead power line would need to be extended approximately 1,200 metres to service a Water Reclamation Centre at Site WH1-West. The utility provider for natural gas in this area is Enbridge. Enbridge has advised that the closest supply of natural gas available is on 2nd Concession but only as far north as Algonquin Forest Drive. As such, the natural gas service would need to be extended approximately 2,500 metres
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Bell has pole mounted lines on 2nd Concession between Queensville Side Road and Holborn Road and has advised that they can provide phone (voice/fax) and DSL internet service to the site. The Town of East Gwillimbury does not currently have any potable water watermains in the area of Site WH1 West. However, as part of the QHLS Wastewater Servicing project a New York Region distribution watermain is planned to be installed along 2nd Concession. This line would need to be extended approximately 2,500 metres to provide a water connection at WH1 West. Access to WH1 West would be provided by two entrances from 2nd Concession. The south entrance would provide direct access to the employee and visitor parking lot at the Administration Building, while the north entrance would be used as the service entrance, and would provide service vehicles with access to the on-site road network. The on-site access road network includes two loops, which would provide service vehicles with access to all Site buildings. North of Queensville Side Road, 2nd Concession is a local two lane roadway servicing the homes and farms on 2nd Concession. For the Water Reclamation Centre to be located at WH1 West approximately 1,500 metres of 2nd Concession would have to be upgraded to accommodate the larger service vehicles. Upgrading of the roadway would be incorporated with the construction of the conveyance infrastructure to the Water Reclamation Centre and Outfall from the Water Reclamation Centre which is also located within the 2nd Concession right-of-way. Queensville Side Road is a major east-west York Region transportation corridor that can accommodate the vehicle traffic associated with the Water Reclamation Centre. 3.4.3.5 Site WH1 West Carbon Footprint
As described in Section 3.3.5, the carbon footprint was calculated as an indicator for each of the Alternatives. The carbon footprint for Site WH1 West is shown in Table 3.5. Table 3.5: Carbon Footprint for Water Reclamation Centre Site WH1 West
Equivalent CO2 generated in tones CO2e per year Conveyance To Approximately 149 tonnes CO2e/yr Conveyance From Approximately 54 tonnes CO2e/yr Total Approximately 203 tonnes CO2e/yr Facility Approximately 2,780 tonnes CO2e/yr Total for Site WH1 West Approximately 2,983 tonnes CO2e/yr
3.4.4 WH1 East
3.4.4.1 Site WH1-East Facility Layout
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WH1 East Water Reclamation Centre Site Layout is shown in Figure 3.12
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Figure 3.12: WH1 East Water Reclamation Centre Site Layout
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3.4.4.2 Site WH1 East Geotechnical Assessment and Structural Design
To assess the geotechnical conditions at site WH1 East two boreholes were drilled. Fill extends to a depth of around 1.5 metres. Native deposits below the fill generally consist of silt in compact to very dense condition, overlying clayey silt with hard consistency and very dense silty sand. Groundwater level measured in monitoring wells installed in the two boreholes was 1.6 metres below local ground level in one well and the other was dry at last reading. Appendix C contains the geotechnical investigation report for the three Water Reclamation Centre sites for which access was provided. There are no anticipated unusual foundation issues for this site. Expected Serviceability Limit States and Ultimate Limit States bearing capacities will be sufficiently high (200 to 400 kPa at Serviceability Limit States and 300 to 600 kPa at Ultimate Limit States) to allow conventional strip/spread footings below buildings and reinforced floor slabs to support in-ground and above grade tank structures. All foundations would be founded in native subgrade below frost depth or otherwise protected from frost, and typical checks for buoyant effects on the in-ground tanks would need to be made. The topography at Site WH1 East has been noted to slope down from southeast towards northwest with a grade of about 4.0 to 5.0 percent. This topography could require some cuts and fills across the site and possibly earth retaining structures along site roads or adjacent to structures. 3.4.4.3 Conveyance Infrastructure To/From Site WH1 East
Alternative Water Reclamation Centre Site WH 1 East is located on Leslie Street north of Queensville Sideroad and south of Holborn Road. Figure 3.13 shows the location of alternative Water Reclamation Centre Site WH 1 East and associated wastewater and treated effluent conveyance infrastructure routes. Appendix D contains the plan and profile figures for the conveyance infrastructure routes from the location of the proposed Queensville West Pumping Station to Site WH 1 East and from the site to a potential discharge location in the East Holland River at Queensville Side Road. The route for the RO concentrate forcemain is also shown.
")
")
_̂
WH2
WH1West
WH1East
24
30
2nd ConcessionPumping Station
Holland LandingPumping Station
Queensville WestPumping Station
Town ofEast Gwillimbury
Holborn Road
Queensville Sideroad
Woodbine Avenue
Doane Road
Mount Albert Road
Leslie Street
2nd Concession
Holland Landing Road
Bathurst StreetHwy 11
Yonge Street
UTM Zone 17N, NAD 83
WH1-East Water ReclamationCentre and Associated
Conveyance InfrastructureRoutes
Figure 3.13Basemapping: Produced by CRA under license from RegionalMunicipality of York, and Ontario Ministry of Natural Resources,Land Information Ontario (LIO), 2011. © Queens Printer 2012
²500 0 500250 Meters
1:40,000
This drawing has been prepared for the use of CRA's client and may not be used, reproduced or relied upon by third parties,except as agreed by CRA and its client, as required by law or for use by governmental reviewing agencies. CRA accepts no responsibility, and denies any liability whatsoever, to any partythat modifies this drawing without CRA's express written consent.
LegendUYSS Service AreaProposed Route to OutfallProposed Route fromQueensville West Pumping StationProposed Route from2nd Concession Pumping Station
_̂ Proposed Outfall
")Queensville HollandLanding Sharon WastewaterServicing System - Pumping StationQueensville HollandLanding Sharon WastewaterServicing System - Infrastructure
Existing Approved Holland LandingLagoon Water Pollution Control Plant Area Suitable for Water Reclamation Centre Area Unsuitable for Water Reclamation Centre Oak Ridges Moraine BoundaryWatercourseWaterbodyProposed RoadMunicipal Division
050278(REP081)GIS-WA005_WH1-East January 31,2013
050278 (81) York Region No. 74270 Page 54
Technical Concept Level 2 Document Upper York Sewage Solutions IEA
Wastewater collected from the QHLS Wastewater Servicing System would be conveyed to Site WH 1 East along 2nd Concession, Holborn Road and Leslie Street via the following forcemains:
Twin forcemains, each with an approximate diameter of 600 mm, from the Queensville West Pumping Station.
Twin forcemains, each with an approximate diameter of 750 mm, from the 2nd Concession Pumping Station. The forcemains from the 2nd Concession Pumping Station to a point at the Queensville West Pumping Station are part of the QHLS Wastewater Servicing project. From this end point, the twin forcemains would be extended to the proposed Water Reclamation Centre as part of the UYSS EA.
Twin forcemains from a future Queensville East Pumping Station
From the Queensville West Pumping Station, the distance along 2nd Concession, Holborn Road and Leslie Street is approximately 5.5 km. The new conveyance infrastructure would be constructed primarily using conventional open-cut methods and would all be built within the existing 2nd Concession, Holborn Road, and Leslie Street rights-of-way. This route is slightly longer than an alternative going east on Queensville Side Road and north on Leslie Street, but avoids an area of higher elevation on Leslie Street that would result in increased operating costs due to pumping. From Site WH1 East, the RO concentrate forcemain travels a distance of approximately 12.3km along Leslie Street, Holborn Road, 2nd Concession and Green Lane East to the Newmarket Pumping Station. The new conveyance infrastructure would be constructed primarily using conventional open-cut methods and would all be built within the existing Leslie Street, Holborn Road, 2nd Concession, and Green Lane East rights-of-way. For watercourse crossings, alternative construction methods such as jacking and boring or directional drilling may be required. This route is slightly longer than an alternative going east on Queensville Side Road and north on Leslie Street, but avoids an area of higher elevation on Leslie Street that would result in increased operating cost due to pumping. A gravity outfall pipe, approximately 1200 mm in diameter, would be constructed from Site WH 1 East north along Leslie Street, west along Holborn Road, south along 2nd Concession, and west along Queensville Sideroad (all within the road rights-of-way) to the East Holland River. The gravity outfall pipe would be approximately 7.5 km long and constructed primarily using conventional open-cut methods. For watercourse crossings, alternative construction methods such as jacking and boring or directional drilling may be required. 3.4.4.4 Site WH1 East Servicing and Access
Hydro One currently has a 44kV service on Leslie Street adjacent to Site WH1 East. This line can be used to provide power to the Water Reclamation Centre at WH1 East. The utility provider for natural gas in this area is Enbridge. Enbridge has an existing natural gas main along Leslie Street passing WH1 East that would be used to supply the Water Reclamation Centre.
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Bell has buried lines along Leslie Street passing Site WH1 East and has advised that they can provide phone (voice/fax) and DSL internet service to the site. The Town of East Gwillimbury has an existing 250 mm diameter potable water watermain on Leslie Street but only for 800 metres north of Queensville Side Road (terminating opposite the Cemetery). To supply potable water to Site WH1 East, this watermain would need to be extended approximately 300 metres. Access to WH1 East would be provided by one entrance from Leslie Street, which would result in all vehicles that visit the Site entering and exiting at the same location. The entrance would provide direct access to the employee and visitor parking lot at the Administration Building. Driving past the Administration Building, service vehicles would have access to the on-site access road network. The on-site access road network is designed as a loop, which would provide service vehicles with direct access to all Site buildings. Leslie Street is a major north-south York Region transportation corridor that can accommodate the vehicle traffic associated with the Water Reclamation Centre. The location on the site of the single entrance would be a suitable distance from the top of the hill on Leslie Street to have visual line of sight for safe access from the Water Reclamation Centre onto Leslie Street. 3.4.4.5 Site WH1 East Carbon Footprint
As described in Section 3.3.5, the carbon footprint was calculated as an indicator for each of the Alternatives. The carbon footprint for Site WH1 East is shown in Table 3.6. Table 3.6: Carbon Footprint for Water Reclamation Centre Site WH1 East
Equivalent CO2 generated in tones CO2e per year Conveyance To Approximately 188 tonnes CO2e/yr Conveyance From Approximately 40 tonnes CO2e/yr Total Approximately 228 tonnes CO2e/yr Facility Approximately 2,780 tonnes CO2e/yr Total for Site WH1 East Approximately 3,008 tonnes CO2e/yr
3.4.5 WH2
3.4.5.1 Site WH2 Facility Layout
WH2 Water Reclamation Centre Site Layout is shown in Figure 3.14
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Figure 3.14: WH2 Water Reclamation Centre Site Layout
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3.4.5.2 Site WH2 Geotechnical Assessment and Structural Design
To assess the geotechnical conditions at WH2 four boreholes were drilled on the western part of the property. Fill deposits ranged from 1.0 to 1.5 metres deep. The native soils consist of granular deposits of silt and sandy silt to silty sand till, generally with compact to very dense relative density and extending to the termination depth of the boreholes at 10 to 20 metres. However, granular material in loose condition was noted in Boreholes WH2-2 and WH2-4 at a depth of 7 to 8 metres and again in Borehole WH2-2 at a depth of 19 metres. Groundwater levels measured in monitoring wells installed in three of the boreholes were 5.7 to 1.3 metres below local ground level. Appendix C contains the geotechnical investigation report for the three Water Reclamation Centre sites for which access was provided. This site exhibits variability in geotechnical conditions between the borehole locations. The expected bearing resistances of 200 kPa at Serviceability Limit States and 300 kPa at Ultimate Limit States are generally adequate for conventional strip/spread footing foundations for the structures. However, similar to some areas of site WH1, the loose layer of granular material present in two of the boreholes will require additional consideration to confirm the extent of the loose layer. The loose material at a depth of 7 to 8 metres could be removed below the in-ground tank foundations without great difficulty. However, the loose material noted at 19 metres is more problematic. If additional geotechnical investigation determines that the extent of this loose material is significant and could consolidate under additional loading, then deep foundations or ground improvement techniques may need to be evaluated for specific areas within this site. All foundations would be founded below frost depth or otherwise protected from frost. Similar to the west side of site WH1, the western segment of WH2 is relatively flat. The site for the Water Reclamation Centre is relatively flat and is only above the East Holland River flood line elevation by 1 to 2 metres. Therefore in an extreme flood event the groundwater elevation could be near grade level and this should be used for design of structures at this site. 3.4.5.3 Conveyance Infrastructure To/From Site WH2
Alternative Water Reclamation Centre Site WH2 is located on the east side of 2nd Concession just north of Queensville Sideroad. Figure 3.15 shows the location of alternative Water Reclamation Centre Site WH2 and associated wastewater and treated effluent conveyance infrastructure routes. Appendix D contains the plan and profile for the conveyance infrastructure routes from the location of the proposed Queensville West Pumping Station to Site WH2 and from the site to a potential discharge location in the East Holland River at Queensville Side Road. The route for the RO concentrate forcemain is also shown.
")
")
_̂
WH2
WH1West
WH1East
2nd ConcessionPumping Station
Holland LandingPumping Station
Queensville WestPumping Station
Town ofEast Gwillimbury
Holborn Road
Queensville Sideroad
Woodbine Avenue
Doane Road
Mount Albert Road
Leslie Street
2nd Concession
Holland Landing Road
Bathurst Street
24
30
Hwy 11Yonge Street
UTM Zone 17N, NAD 83
WH2 Water ReclamationCentre and Associated
Conveyance InfrastructureRoutes
Figure 3.15Basemapping: Produced by CRA under license from RegionalMunicipality of York, and Ontario Ministry of Natural Resources,Land Information Ontario (LIO), 2011. © Queens Printer 2012
²500 0 500250 Meters
1:40,000
This drawing has been prepared for the use of CRA's client and may not be used, reproduced or relied upon by third parties,except as agreed by CRA and its client, as required by law or for use by governmental reviewing agencies. CRA accepts no responsibility, and denies any liability whatsoever, to any partythat modifies this drawing without CRA's express written consent.
LegendUYSS Service AreaProposed Route to OutfallProposed Route fromQueensville West Pumping StationProposed Route from2nd Concession Pumping Station
_̂ Proposed Outfall
")Queensville HollandLanding Sharon WastewaterServicing System - Pumping StationQueensville HollandLanding Sharon WastewaterServicing System - Infrastructure
Existing Approved Holland LandingLagoon Water Pollution Control Plant Area Suitable for Water Reclamation Centre Area Unsuitable for Water Reclamation Centre Oak Ridges Moraine BoundaryWatercourseWaterbodyProposed RoadMunicipal Division
050278(REP081)GIS-WA006_WH2 January 31,2013
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Wastewater collected from the QHLS Wastewater Servicing System would be conveyed to Site WH2 along 2nd Concession via the following forcemains:
Twin forcemains, each with an approximate diameter of 600 mm, from the Queensville West Pumping Station.
Twin forcemains, each with an approximate diameter of 750 mm, from the 2nd Concession Pumping Station. The forcemains from the 2nd Concession Pumping Station to a point at the Queensville West Pumping Station are part of the QHLS Wastewater Servicing project. From this end point, the twin forcemains would be extended to the proposed Water Reclamation Centre as part of the UYSS EA.
Twin forcemains from a future Queensville East Pumping Station
From the Queensville West Pumping Station, the distance along 2nd Concession is approximately 750 m. The new conveyance infrastructure would be constructed primarily using conventional open-cut methods and would all be built within the existing 2nd Concession right-of-way. From Site WH1 West, the RO concentrate forcemain travels a distance of approximately 7.2km along 2nd Concession and Green Lane East to the Newmarket Pumping Station. The new conveyance infrastructure would be constructed primarily using conventional open-cut methods and would all be built within the existing 2nd Concession, and Green Lane East rights-of-way. For watercourse crossings, alternative construction methods such as jacking and boring or directional drilling may be required. A gravity outfall pipe, approximately 1200 mm in diameter, would be constructed from WH2 along the 2nd Concession and the Queensville Sideroad road rights-of-way to the East Holland River. The gravity outfall pipe would be approximately 2.5 km long and constructed primarily using conventional open-cut methods. For watercourse crossings, alternative construction methods such as jacking and boring or directional drilling may be required. 3.4.5.4 Site WH2 Servicing and Access
Hydro One currently has a 44kV service on 2nd Concession as far north as Queensville Side Road, as well as along Queensville Side Road adjacent to Site WH2. As such, the electrical service for Site WH2 is readily available. The utility provider for natural gas in this area is Enbridge. Enbridge has advised that the closest supply of natural gas available is on 2nd Concession but only as far north as Algonquin Forest Drive. As such, the natural gas service would need to be extended approximately 1,500 metres. Bell has pole mounted lines on 2nd Concession between Queensville Side Road and Holborn Road and on Queensville Side Road between 2nd Concession and Leslie Street, and has advised that they can provide phone (voice/fax) and DSL internet service to the site.
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The Town of East Gwillimbury does not currently have any potable water watermains in the area of Site WH2. However, as part of the QHLS Wastewater Servicing project a new York Region distribution watermain is planned to be installed along 2nd Concession. This line would need to be extended approximately 1,500 metres to provide a water connection at WH2 West. Access to Site WH2 would be provided by two entrances; the north entrance from 2nd Concession would provide direct access to the employee and visitor parking lot at the Administration Building, while the south entrance from Queensville Side Road would be used as the service vehicle entrance, and would provide access to the on-site road network. The WH2 Site layout allows an extensive network of on-site access roads that includes multiple loops, which would provide service vehicles with direct access to all Site buildings. For the employee and visitor access a short section of 2nd Concession would be upgraded with the construction of the conveyance infrastructure to the Water Reclamation Centre and Outfall from the Water Reclamation Centre which is also located within the 2nd Concession right-of-way. Queensville Side Road is a major east-west York Region transportation corridor that can accommodate the vehicle traffic associated with the service vehicle entrance to the Water Reclamation Centre. 3.4.5.5 Site WH2 Carbon Footprint
As described in Section 3.3.5, the carbon footprint was calculated as an indicator for each of the Alternatives. The carbon footprint for Site WH2 is shown in Table 3.7. Table 3.7: Carbon Footprint for Water Reclamation Centre Site WH2
Equivalent CO2 generated in tones CO2e per year Conveyance To Approximately 149 tonnes CO2e/yr Conveyance From Approximately 54 tonnes CO2e/yr Total Approximately 203 tonnes CO2e/yr Facility Approximately 2,780 tonnes CO2e/yrTotal for Site WH2 Approximately 2,983 tonnes CO2e/yr
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Section 4.0 YDSS Modifications Alternative Routes
As mentioned, three alternative routes from the existing Newmarket and Bogart Creek Pumping Station to the existing Aurora Pumping Station were developed. A description of each of the routes and the resulting carbon footprint is provided below. Details on the basis of design, alternative construction methods and operating strategy are provided in Appendix E.
4.1 Route A
Alternative Route A is 5.4 km in length. It exits the Newmarket Pumping Station and travels south along Bayview Parkway towards Davis Drive for approximately 1.6 km, alongside the East Holland River, George Richardson Park and Mabel Davis Conservation Area. Immediately south of Davis Drive, the forcemain travels south along Charles Street for approximately 0.2 km and continues west along Queen Street for another 0.1 km. Alternative Route A then travels alongside the East Holland River south on Tom Taylor Trail (until Water Street) and then on Cotter Street adjacent to the Canadian National Railway (CNR) line through the Wesley Brooks Memorial Conservation Area and Cane Parkway towards Mulock Drive for about 2.1 km. South of Mulock Drive, the Alternative Route A travels for approximately 1.4 km through Bailey Ecological Park beside the CNR line, past the Hydro-electric corridor and connects to the Newmarket gravity sanitary sewer. The existing Newmarket 1050 mm diameter gravity sewer ultimately discharges to the Aurora Pumping Station on St.John’s Sideroad. The conceptual alignment is shown on Figure F.1 in Appendix F.
Alternative Route A follows the existing Newmarket forcemain alignment. This allows Alternative Route A to be constructed within the modifiable easement of the existing Newmarket forcemain. The Alternative Route A forcemain has similar lengths, topographical constraints, and TDH as the existing Newmarket forcemain. Modifications at the Newmarket Pumping Station are similar for all three alternative routes. However Alternative Route A has the lowest total dynamic head and therefore would have the lowest operating cost for energy. This forcemain alternative can be constructed with a stand 2.5 to 4 m of cover and be designed with a uniform uphill slope for the majority of its length. This minimizes the number of air release and drain chambers required. Alternative Route A length is minimized by following the existing Newmarket forcemain alignment and this helps minimize effects on existing utilities. Alternative Route A would be constructed in close proximity to the East Holland River, Fairy Lake and Cane Parkway stormwater management pond, the Wesley Brooks Memorial Conservation Area, Bailey Ecological Park and the Hydro-electric corridor, and high density urban roads (Charles Street and Queen Street) within the Town of Newmarket.
As part of this alternative, a new Bogart Creek 550 mm HDPE forcemain, in addition to the existing Bogart Creek forcemain would convey wastewater west from Bogart Creek Pumping Station on Pearson Street to the new Newmarket forcemain interconnection on Cotter Street. The new Bogart Creek forcemain would connect to the new Newmarket forcemain; the new Bogart Creek forcemain would not connect to the existing Newmarket forcemain. Figure F.1.9 in Appendix F shows the conceptual alignment of the new Bogart Creek forcemain.
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The new Newmarket forcemain would be approximately 900 mm diameter Concrete Pressure Pipe (CPP) with a corrosion protection liner for about 2.2 km and 1050 mm diameter High Density Polyethylene (HDPE) for about 3.2 km. A 900mm diameter CPP is specified where there is open cut construction and a 1050 mm diameter HDPE is specified for trenchless construction methods and creek crossings. The new Bogart Creek forcemain would be approximately 550 mm diameter HDPE for 0.5 km. The carbon footprint for YDSS Modification: Route A is shown in Table 4.1. Table 4.1: Carbon Footprint for YDSS Modification: Route A
Equivalent CO2 generated in tones CO2e per year Conveyance Approximately 207 tonnes CO2e/yr
4.2 Route B
Alternative Route B is 5.8 km in length. It primarily follows the existing Newmarket forcemain from Newmarket Pumping Station south along Bayview Parkway towards Davis Drive for approximately 1.6 km, alongside the East Holland River, George Richardson Park and Mabel Davis Conservation Area. Alternative Route B diverts from the route of the existing Newmarket forcemain at Davis Drive and Bayview Parkway where it travels east along east Davis Drive for about 0.1 km, south on Prospect Street towards Mulock Drive for about 2.2 km and then west on Mulock Drive for approximately 0.6 km. South of Mulock Drive, Alternative Route B travels for about 1.4 km through Bailey Ecological Park beside the CNR line past the Hydro-electric corridor and connects to the existing Newmarket gravity sanitary sewer. The existing Newmarket 1050 mm diameter gravity sewer ultimately discharges to the Aurora Pumping Station on St.John’s Sideroad. The conceptual alignment is shown on Figure F.2 in Appendix F. A portion of Alternative Route B also follows the Bogart Creek forcemain along Pearson Street from the Bogart Creek Pumping Station to the proposed Newmarket forcemain on Prospect Street. As part of this alternative, a new Bogart Creek 550mm HDPE forcemain, forcemain in addition to the existing Bogart Creek forcemain will convey wastewater west from Bogart Creek Pumping Station on Pearson Street to the new Newmarket forcemain interconnection on Prospect Street. The new Bogart Creek forcemain will connect to the new Newmarket forcemain; the new Bogart Creek forcemain will not connect to the existing Newmarket forcemain. Figure F.2.9 in Appendix F shows the conceptual alignment of the new Bogart Creek forcemain. Alternative Route B follows existing road right-of-ways and the modifiable existing Newmarket forcemain easement. Modifications at the Newmarket Pumping Station are similar for all three alternative routes. The total dynamic head for Alternative Route B is higher than Alternative Route A and therefore energy operating costs would be higher. The profile drawing shows that this alignment has a number of high and low points and therefore a larger number of air release and drain chambers are required than Alternative Route A. Construction of the proposed
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forcemain on Prospect Street would require full closure of the roadway. In addition the existing local storm sewer, sanitary sewer and watermain would have to be relocated within the road right-of-way to provide space for installation of the new Newmarket forcemain. Alternative Route B avoids passing through the Fairy Lake, Wesley Brooks Memorial Conservation Area and avoids some areas alongside the East Holland River by using Prospect Street for the forcemain alignment. Construction methods would include open-cut and trenchless techniques as shown on the figures in Appendix F. The forcemain would be approximately 900 mm diameter Concrete Pressure Pipe (CPP) with a corrosion protection liner for about 4.3 km and 1050 mm diameter High Density Polyethylene (HDPE) for about 1.5 km for trenchless construction methods and creek crossings. The new Bogart Creek forcemain would be approximately 550 mm diameter HDPE for 0.4 km. The carbon footprint for YDSS Modification: Route B is shown in Table 4.2 Table 4.2: Carbon Footprint for YDSS Modification: Route B
Equivalent CO2 generated in tones CO2e per year Conveyance Approximately 235 tonnes CO2e/yr
4.3 Route C
Alternative Route C is 7.1 km in length. It follows the existing Newmarket forcemain from the Newmarket Pumping Station south along Bayview Parkway towards Davis Drive for approximately 1.6 km, alongside the East Holland River, George Richardson Park and Mabel Davis Conservation Area. Immediately south of Davis Drive, the forcemain route travels south along Charles Street for about 0.2 km, east along Queen Street for another 0.1 km and then south on Prospect Street and Bayview Avenue towards St.John’s Sideroad for approximately 3.8 km. The route continues west on St.John’s Sideroad for approximately 1.4 km until it reaches the Aurora Pumping Station. The conceptual alignment is shown on Figure F.3 in Appendix F. A portion of Alternative Route C also follows the Bogart Creek forcemain along Pearson Street from the Bogart Creek Pumping Station to the proposed Newmarket forcemain on Prospect Street. As part of this alternative, a new Bogart Creek 550 mm diameter HDPE forcemain, in addition to the existing Bogart Creek forcemain would convey wastewater west from Bogart Creek Pumping Station on Pearson Street to the new Newmarket forcemain interconnection on Prospect Street. The new Bogart Creek forcemain would connect to the new Newmarket forcemain; the new Bogart Creek forcemain would not connect to the existing Newmarket forcemain. Figure F.3.11 in Appendix F shows the conceptual alignment of the new Bogart Creek forcemain.
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Alternative Route C follows existing road right-of-ways and the modifiable existing Newmarket forcemain easement. Modifications at the Newmarket Pumping Station are similar for all three alternative routes. However Alternative Route C has the highest TDH and therefore would have the highest operating cost for energy. The profile drawing shows that this alignment has the highest number of high and low points and therefore a higher number of air release and drain chambers are required than alternative routes A and B. Construction of the proposed forcemain on Prospect Street, would require full closure of this roadway. In addition the existing local storm sewer, sanitary sewer and watermain on Prospect Street would have to be relocated within the road right-of-way to provide space for installation of the new Newmarket forcemain. Alternative Route B avoids passing through the Fairy Lake, Wesley Brooks Memorial Conservation Area, the Bailey Ecological Park and the Hydro-electric corridor and avoids some areas alongside the East Holland River by using Prospect Street, Bayview Ave and St. John’s Side Road for the forcemain alignment. With the exception of river/creek crossings, all of the Alternative Route C would be constructed using open-cut methods. Trenchless techniques would be used at river/creek crossings. The forcemain would be approximately 900 mm diameter Concrete Pressure Pipe (CPP) with a corrosion protection liner for about 6.8 km and 1050 mm diameter High Density Polyethylene (HDPE) for about 0.3 km The carbon footprint for YDSS Modification: Route C is shown in Table 4.3 Table 4.3: Carbon Footprint for YDSS Modification: Route C
Equivalent CO2 generated in tones CO2e per year Conveyance Approximately 241 tonnes CO2e/yr
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Section 5.0 Summary
Technical Concept Level 2 Document provides an enhanced concept level design for the preferred Alternative to the Undertaking, building on the work documented in Technical Concept Level 1 Document. Technical Concept Level 2 Document will be used for reference purposes for assessing the short-listed Alternative Methods of Carrying Out the Undertaking, in accordance with the Upper York Sewage Solutions (UYSS) Environmental Assessment Terms of Reference approved by the Minister of the Environment in March 2010. The short-listed Alternative Methods for Carrying out the Undertaking comprise five locations for the Water Reclamation Centre and three routes for the YDSS modifications. The Conceptual Design and Conceptual Site Layout for the Water Reclamation Centre are described in this document. The Technical Workplan (Appendix H) of the Approved Terms of Reference identifies carbon dioxide footprint as the preliminary evaluation criterion to compare Alternative Methods, with the Equivalent tonnes of Carbon Dioxide per year (CO2e/yr) as the Indicator for this criterion. The carbon footprint for each Alternative Method is summarized in Table 5.1. Table 5.1: Carbon Dioxide Footprint for Alternative Methods
Component Alternative Carbon Footprint Indicator Equivalent tonnes of Carbon Dioxide per year
Water Reclamation Centre Site
Site 24 Approximately 2, 983 CO2e/yr
Site 30 Approximately 3,008 CO2e/yr
Site Willing Host 1 West Approximately 2,983 CO2e/yr
Site Willing Host 1 East Approximately 2,008 CO2e/yr
Site Willing Host 2 Approximately 2,983 CO2e/yr
YDSS Modifications Route
Route A. Approximately 207 CO2e/yr
Route B Approximately 235 CO2e/yr
Route C Approximately 241 CO2e/yr
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Section 6.0 References
Ontario Ministry of the Environment. (June 2010). Lake Simcoe Phosphorus Reduction Strategy. Ontario Ministry of the Environment. (2008). Design Guidelines for Sewage Works Regional Municipality of York. (May 2008). Unit Rates Waste and Wastewater Master Plan Update. Regional Municipality of York. (December 2009). York Region Official Plan. R.V. Anderson Associates Limited. (April 2000). YDSS Extension to Holland Landing/ Queensville Class EA, Project File Report. XCG Environmental Engineers & Scientists. (February 2010). Draft Lake Simcoe Watershed Water Quality Trading Feasibility Study.
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Section 7.0 List of Abbreviations
AADF Annual Average Day Flow BFP Belt Filter Press BNR Biological Nutrient Removal BOD Biochemical Oxygen Demand BOD5 5-day Biochemical Oxygen Removal CBOD Carbonaceous Biochemical Demand CH4 Methane CF Carbon Footprint CNR Canadian National Railway CO2 Carbon Dioxide CO2e Carbon Dioxide Equivalent CO2e/yr Carbon Dioxide Equivalent per Year COD Chemical Oxygen Demand CPP Concrete Pressure Pipe CWQG Canadian Water Quality Guidelines DO Dissolved Oxygen E. coli Escherichia coli EA Environmental Assessment EC Electrical Conductivity GBT Gravity Belt Thickener GHG Green House Gases GWP Global Warming Potential HDPE High Density Polyethylene HRT Hydraulic Retention Time IPCC Intergovernmental Panel on Climate Change ISO International Organization for Standards kg CO2e Mass of Carbon Dioxide Equivalents LCA Life Cycle Assessment Lpm Litres per minute MLD Million Litres per Day/Megalitres per Day MOE Ministry of the Environment (Ontario) NTU Nephelometric Turbidity Units N2O Nitrous Oxide pH Negative logarithm of hydrogen ion concentration PRS Phosphorus Reduction Scheme PWQO Provincial Water Quality Objectives QHLS Queensville, Holland Landing, Sharon RO Reverse Osmosis ToR Terms of Reference TAR Third Assessment Report TN Total Nitrogen TS Total Solids TSS Total Suspended Solids
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US EPA United States Environmental Protection Agency UV Ultra Violet Radiation UYSS Upper York Sewage Solutions WAS Waste Activated Sludge WPCP Water Pollution Control Plant WRC Water Reclamation Centre YDSS York Durham Sewage System
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Section 8.0 Glossary of Terms
Advanced Treatment Additional treatment to remove constituents remaining after conventional secondary treatment.
Advantage A relative term used to indicate that a particular condition is deemed to offer a benefit when compared to another condition.
Alternative Both alternative methods and alternatives to a proposed undertaking.
Alternative Methods of Carrying out the Undertaking (Interchangeable with Alternative Methods)
Different ways of implementing the Preferred Alternative To the Undertaking.
Alternatives To the Undertaking (Interchangeable with Alternatives To)
Functionally different ways of approaching a problem or opportunity, from which a Preferred Alternative is selected.
Ammonia (un-ionized) The neutral form of ammonia-nitrogen in water. Un-ionized ammonia is the principal form of ammonia that is toxic to aquatic life. The percentages of un-ionized ammonia (NH3) in aqueous ammonia solution are dependent on temperature and pH conditions. The PWQO for un-ionized ammonia is 20 ug/L.
Anaerobic
Without air, specifically oxygen. Anaerobic processes happen in the absence of oxygen.
Anoxic
An environment without dissolved oxygen, but with chemically bound oxygen in the form of nitrate/nitrite present. Under anoxic conditions, nitrate nitrogen is converted biologically to nitrogen gas in the absence of oxygen.
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Aquatic Refers to an environment that consists of, relates to, or is in water; or to animals and plants living or growing in, on, or near the water.
Beneficial reuse The use of reclaimed water to benefit the end user or receiver (e.g., for irrigation of crops), as opposed to disposal, where there is no positive impact resulting from the discharge of water.
Biogas Gas produced by the breakdown of organic material in the absence of oxygen. Biogas (e.g., methane) can be burned for energy generation.
Biological nutrient removal
The removal of nutrients (nitrogen and phosphorus) by microorganisms. Conditions are created to encourage the growth of desired microbes in various stages of the biological (secondary) treatment system take up or otherwise use nutrients present in the wastewater stream.
Biosolids
Wastewater sludge that has been stabilized through one of many stabilization processes (e.g., digestion, alkaline stabilization).
Class A Biosolids are biosolids in which pathogens are reduced to. below detectable levels, as defined by the US EPA.
Class B Biosolids are biosolids in which pathogens are reduced to levels that are unlikely to pose a threat to public health and the environment under specific use conditions, as defined by the US EPA. Class B Biosolids cannot be sold or given away in bags or other containers or applied on lawns or home gardens (i.e. site restrictions exist on land application).
BOD Biochemical oxygen demand, a measure of the organic content in wastewater. BOD represents the amount of oxygen required by microorganisms to degrade the organic matter.
Buffer A protective barrier; any of various devices or pieces of material for reducing shock, damage or interactions due to contact.
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Class Environmental Assessment
A Class Environmental Assessment (Class EA) is approved under Ontario's Environmental Assessment Act for a class of specified undertakings. There are currently 10 approved Class EAs in Ontario. The preparation and completion of a Class EA for a specified project involves a streamlined process applicable to projects (undertakings) with predictable environmental impacts. See also Municipal Class Environmental Assessment.
Commitments Represents a pledge from a proponent about a certain course of action, that is, "I will do this, at this time, in this way." Proponents document obligations and responsibilities, which they agree to follow, in environmental assessment documentation.
Concentrate (RO) See Reverse osmosis concentrate
Conventional activated sludge
The most common biological wastewater treatment process. CAS includes biological treatment (in biological reactors) and secondary clarification. Activated sludge is removed from the secondary clarifiers and returned to the biological reactors to maintain a healthy microbial population.
Criteria / Criterion A set of principles or standards used to compare and judge alternatives. (plural = "criteria", singular = "criterion")
Dewatering A physical operation to reduce the moisture content of sludge or biosolids. Also used in construction to refer to the removal of groundwater by pumping or other means to permit tunneling or excavation without encountering waterlogged soil conditions.
Digestion The decomposition of organic matter in sludge by microorganisms. Digestion may occur under aerobic or anaerobic conditions.
Disadvantage A relative term used to indicate that a particular condition is deemed to be unfavourable or of an inferior condition when compared with another condition.
Discharge to Lake Ontario Alternative
One of the four Alternatives To the Undertaking examined in the UYSS EA. Under this alternative, all wastewater would be conveyed to an appropriate point in the existing York Durham Sewage System, through some combination of tunnel, pumping station(s) and forcemain(s).
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Discharge to Lake Simcoe Alternative
One of the four Alternatives To the Undertaking examined in the UYSS EA. Under this alternative, wastewater from growth in East Gwillimbury and a portion of Newmarket would be conveyed to an advanced wastewater treatment plant for treatment and discharge within the Lake Simcoe watershed, in compliance with the phosphorus loading targets established by the Phosphorus Reduction Strategy under the Lake Simcoe Protection Plan. Wastewater from approved growth in Newmarket and Aurora would continue to be conveyed to the existing York Durham Sewage System.
Disinfection Destruction or removal of disease-causing organisms (pathogens) from wastewater. Disinfection is usually the last stage in the wastewater treatment process.
Do Nothing Alternative One of the four Alternatives To the Undertaking examined in the UYSS EA. Under this alternative, no additional wastewater collection and treatment capacity would be built to accommodate the approved growth.
E. coli A common organism that is found in untreated wastewater. Some forms of E. coli may be pathogenic and along with other pathogenic organisms are damaged or removed during disinfection so that they are no longer a threat to human health.
Effluent Refers to water flowing from a pipe, treatment process, or treatment plant.
Environment The Environmental Assessment Act defines “environment” broadly to include:
i. air, land or water
ii. plant or animal life, including human life
iii. social, economic, and cultural conditions influencing the life of humans or a community
iv. any building, structure, machine or other device or thing made by humans
v. any solid, liquid, gas, odour, heat, sound, vibration, or radiation resulting directly or indirectly from the human activities
vi. any part or combination of the foregoing and the interrelationships between any two or more of them, in or of Ontario
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Environmental Assessment (EA)
A generic term for a study that assesses the potential environmental effects (positive or negative) of a proposal. Key components of an environmental assessment include consultation with government agencies, stakeholders and the public; consideration and evaluation of alternatives; and the management of potential environmental effects. Conducting an environmental assessment promotes good environmental planning before decisions are made about proceeding with a proposal. For the purposes of this Terms of Reference for the UYSS EA, an Environmental Assessment refers to the process and related documentation, including the submission of a Terms of Reference and final Environmental Assessment Report for approval in accordance with the requirements of Part II of the EA Act.
Environmental Assessment Act (EA Act)
Ontario legislation that defines a decision-making process used to promote good environmental planning by assessing the potential effects of certain activities on the environment. The purpose of the EA Act is the betterment of the people of the whole or any part of Ontario by providing for the protection, conservation and wise management in Ontario of the environment.
Environmental effect The effect that a proposed undertaking or its alternatives has or could potentially have on the environment, either positive or negative, direct or indirect, short- or long-term.
Eutrophication Eutrophication describes an excess of nutrients in a water body, which leads to an overgrowth of plants and depletion of dissolved oxygen, which may cause death to fish and other animals.
Evaluation A formal process for comparatively assessing the advantages and disadvantages of alternatives (see Evaluation Methodology).
Flocculation A process where wastewater particles form aggregates, or flocs, which are more readily removed by settling. Flocculation follows chemical addition and rapid mixing.
Greenbelt Act, 2005 Enacted in 2005, provides for the establishment of the Greenbelt Plan, that among other things establishes a network of countryside and open space areas which supports the Oak Ridges Moraine and the Niagara Escarpment and designates permitted uses and activities within certain area.
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Groundwater Water below the surface of the ground that occupies a zone of the earth's mantle that is saturated with water.
Growth Plan for the Greater Golden Horseshoe (Growth Plan)
Established under the authority of subsection 7 (6) of the Places to Grow Act, 2005, the Growth Plan aims to manage growth and development in the designated area of Ontario in a way that supports economic prosperity, protects the environment, and develops a culture of conservation.
Guidelines Not legally enforceable, guidelines are established by government or other agencies to provide general guidance.
Headworks Precedes the first stage of a generic wastewater treatment process, headworks often include screening, grit removal, and other preliminary treatment processes to improve overall efficiency and protect downstream processes.
Holland Marsh Consists of 2900 ha of organic (“muck”) soil draining to the Holland River used for farming. The region is largest area of organic soil developed for agriculture in the province and one of the most intensive areas of agricultural production in the country (From: The University of Guelph Muck Crops Research Station, http://www.uoguelph.ca/plant/stations/muck_crops/).
Infiltration Extraneous flow that enters a wastewater collection system from groundwater through broken pipes, pipe joints, connections, and manhole walls.
Inflow Extraneous flow that enters a wastewater collection system from overland flow (e.g., stormwater and snowmelt) through drains, manhole covers, and cross connections.
Influent Refers to water flowing from a pipe, treatment process, into a treatment plant.
Innovative Wastewater Treatment Technologies Alternative
One of the four Alternatives To the Undertaking examined in the UYSS EA. Under this alternative, wastewater from approved growth in East Gwillimbury and a portion of Newmarket would be conveyed to a Water Reclamation Centre within the Lake Simcoe watershed. Wastewater from the remaining approved growth in Newmarket and Aurora would be conveyed to the existing York Durham Sewage System for treatment and discharge to Lake Ontario.
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Irrigation Application of water to land or soil, often for the purposes of supporting plant growth.
Lagoon Also referred to as a wastewater stabilization pond, lagoons provide biological and physical treatment of wastewater
Lake Simcoe Phosphorus Reduction Strategy (PRS)
The Lake Simcoe Protection Plan commits the Province, working with the Lake Simcoe Region Conservation Authority, local stakeholders, municipalities and other partners, to develop a comprehensive Phosphorus Reduction Strategy. The Strategy identifies specific reduction goals and potential reduction opportunities to achieve phosphorus loading targets for Lake Simcoe. In addition, the Strategy incorporates several key concepts and strategic directions including: adaptive management, watershed approach, stewardship and community action, source-specific actions, monitoring and compliance, and research, modeling and innovation.
Lake Simcoe Protection Act, 2008 (LSPA)
Enacted in 2008, provides the authority for the Minister of the Environment to establish the Lake Simcoe Protection Plan. The purpose of the Act is to protect and restore the ecological health of the Lake Simcoe watershed.
Lake Simcoe Protection Plan (LSPP)
Established under the authority of Lake Simcoe Protection Act, 2008 The objectives of the LSPP, approved June 2009, include the protection, improvement or restoration of the elements that contribute to the ecological health of the Lake Simcoe watershed, including, water quality, hydrology, key natural heritage features and their functions, and key hydrologic features and their functions.
Lake Simcoe Region Conservation Authority (LSRCA)
Established under the Conservation Authorities Act, the LSRCA prepares and delivers programs for the management of the renewable natural resources within watersheds in its jurisdiction.
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Membrane filtration A physical solids separation process where water and other small molecules are forced across a thin, porous membrane while larger solid particles are unable to pass through the pores and are effectively removed from the stream.
Microfiltration can remove solids that are 0.08 to 2.0 micrometres (um) in size. Microfiltration can remove TSS, turbidity, micro-organisms, and some bacteria and viruses. Water and dissolved solutes are allowed to pass through the membrane.
Ultrafiltration can remove solids that are 0.005 to 0.2micrometres in size. Ultrafiltration can remove some dissolved solutes, most bacteria, and some viruses and proteins. Water and small molecules are allowed to pass through the membrane.
Definitions for Microfiltration and Ultrafiltration based on Metcalf and Eddy, Wastewater Engineering Treatment and Reuse, 2003
Mesophilic Describes organisms, especially bacteria that thrive at moderate temperatures.
Minister of the Environment (Minister)
The Minister of the Environment is responsible under the EA Act for approval of the ToR and the EA.
Ministry of the Environment (MOE)
The Ministry of the Environment is responsible for protecting air, land and water to ensure healthy communities, ecological protection, and sustainable development for present and future generations of Ontarians.
Mixed liquor The contents of an aeration basin (influent wastewater and return activated sludge)
Monitoring A systematic method for collecting information using standard observations according to a schedule and over a sustained period of time.
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Municipal Class Environmental Assessment (Municipal Class EA)
Approved under the EA Act by the Minister of the Environment and prepared by the Municipal Engineers Association, the Municipal Class EA applies to municipal infrastructure projects including transit, roads, water, and wastewater projects. Projects under the Municipal Class EA are to be undertaken in accordance with approved procedures set out in the Municipal Class EA document.
Non-Potable Water Water that is not intended for human consumption and therefore intended for non-drinking water uses only.
Oak Ridges Moraine (ORM)
An environmentally sensitive, geological landform in south central Ontario, covering 190,000 hectares and is delineated and protected by the Oak Ridges Moraine Conservation Act, 2001 and the Oak Ridges Moraine Conservation Plan.
Oxidation In the context of wastewater treatment, advanced oxidation processes are used to oxidize complex organic compounds in wastewater that are difficult to degrade biologically.
Pathogen A disease causing bacterium, virus or other microorganism.
Permeate (RO) See Reverse osmosis (RO) permeate.
pH A measure of the acidity or alkalinity of a solution.
Phosphorus A chemical element that occurs naturally in the environment and is an essential nutrient needed by plants and animals. Because phosphorus is a nutrient, high levels in a lake encourage the growth of plants and algae. Although some phosphorus is required to support a healthy aquatic ecosystem, too much phosphorus leads to excessive growth of plants and algae in the lake. As these plants decay, dissolved oxygen required by fish and other aquatic species is depleted.
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Phosphorus Loading Targets
Established by the Phosphorus Reduction Strategy under the Lake Simcoe Protection Plan, the phosphorus loading targets aim to reduce the amount of phosphorus entering streams and Lake Simcoe from the subwatersheds and other specific areas within the Lake Simcoe watershed. This will help the Lake Simcoe watershed reduce the amount of phosphorus discharged to surface waters and meet the long-term phosphorus reduction goals in the Lake Simcoe Phosphorus Reduction Strategy.
Phosphorus Reduction Strategy (PRS)
See Lake Simcoe Phosphorus Reduction Strategy
Places To Grow Act, 2005 Enacted in 2005, this legislation provides the authority for the Minister of Energy and Infrastructure to establish the Growth Plan for the Greater Golden Horseshoe (the Growth Plan). The purpose of the Places to Grow Act, 2005 is:
a) to enable decisions about growth to be made in ways that sustain a robust economy, build strong communities and promote a healthy environment and a culture of conservation
b) to promote a rational and balanced approach to decisions about growth that builds on community priorities, strengths and opportunities and makes efficient use of infrastructure
c) to enable planning for growth in a manner that reflects a broad geographical perspective and is integrated across natural and municipal boundaries
d) to ensure that a long-term vision and long-term goals guide decision-making about growth and provide for the co-ordination of growth policies among all levels of government
Potable water Water that is suitable for human consumption.
Potential effect An effect that is deemed possible to result from an activity or implementation of a particular alternative.
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Preferred Alternative The alternative selected that will be studied further to determine if it will be the Undertaking for which approval will be sought, based on an approach for identifying a preferred alternative, namely:
a) Identify a recommended alternative
b) Consult review agencies and the public on the recommended alternative
c) Confirm or select the preferred alternative based on the comments received
Preliminary Study Area In reference to the UYSS EA, extends north to Lake Simcoe, east to Woodbine Avenue, south to 19th Avenue, and west to Bathurst Street. This preliminary study area is the area within which activities associated with the Undertaking will occur and where potential environmental effects will be studied, and it currently includes the UYSS service area.
Primary treatment The first stage of wastewater treatment, involves removal of a portion of suspended solids and organic matter, usually by sedimentation.
Public Means the general public, individual members of the public who may be affected by or have an interest in a project and special interest groups.
Pumping/Forcemain based sewer system
A sewer system that relies on the use of pumps and pressurized pipes (forcemain) to convey wastewater collected from urban areas to a wastewater treatment facility for treatment and discharge of treated effluent.
Quaternary treatment Refers to advanced treatment processes implemented following tertiary treatment to remove remaining constituents that cannot be removed through conventional processes.
Reclaimed water Wastewater that has gone through various treatment processes to meet specific water quality criteria with the intent of being used in a beneficial manner (e.g., irrigation and industrial uses).
Recommended Alternative(s)
An alternative or alternatives that are ranked highest based on the results of a comparative evaluation process.
Regulations A rule or directive made pursuant to legislation and enforced by an authority, like the Ontario Ministry of the Environment.
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Return activated sludge Settled sludge in activated sludge treatment processes that is returned to the biological reactor to maintain a healthy population of microorganisms.
Reverse osmosis A high-pressure membrane separation process in which a liquid is forced across a membrane against osmotic pressure. Osmosis is the passage of pure solvent (such as water) between two solutions separated by a semi-permeable membrane in response to a concentration gradient (i.e. from the lesser to the greater solute concentration). The term osmotic pressure refers to the pressure exerted by the flow of the solvent through the membrane separating two solutions with different concentrations of solute. Reverse Osmosis membranes are effective in removing dissolved constituents with a membrane pore size of 0.001 micrometres (μm) or less.
Reverse osmosis (RO) concentrate
Rejected flow that was not able to pass through the RO membrane and contains the constituents removed from the RO permeate.
Reverse osmosis (RO) permeate
Treated flow that has been filtered through the RO membrane
Sanitary sewage Liquid or waterborne waste, of industrial or commercial origin, or of domestic origin, including human body waste, toilet or other bathroom waste, and shower, tub, culinary, sink and laundry waste.
Secondary treatment The second stage of the wastewater treatment process, involves removal of biodegradable organic matter and suspended solids.
Settling Sedimentation. The removal of particles in suspension by gravity.
Sewer system A network of service branches, trunk and local sewers, pumping stations, and appurtenances all for purposes of conveying sewage. Sewage may be either sanitary sewage or storm sewage.
Sludge Settled biological solids.
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Storm sewage Water that is discharged from a surface as a result of rainfall, snow melt or snowfall.
Surface water Water that exists above the substrate or soil surface, including runoff from precipitation events and snow melt, typically occurring in streams, creeks, rivers, lakes, ponds and wetlands.
Terms of Reference (ToR) The first step in an application for approval to proceed with a project or undertaking under Part II of the Environmental Assessment Act is the submission of a Terms of Reference (ToR) for the Environmental Assessment (EA). Public and agency consultation is required on the preparation and submission of the ToR to the Ministry of the Environment. Approval is required by the Minister of the Environment. If approved, the ToR provides a framework / work plan for the EA.
Tertiary treatment The third stage in the wastewater treatment process, involves removal of residual suspended solids, usually by filtration.
Total Solids (TS) A measure of the non-filterable solids particles.
Total Suspended Solids (TSS)
A measure of the non-filterable solids particles in suspension.
Total Phosphorus (TP) The total concentration of all forms of phosphorus in a solution.
Turbidity A measure of water clarity.
Undertaking An enterprise, activity, proposal, plan or program in respect of a commercial or business enterprise or activity of a person or persons that has potential environmental effects and is assessed in accordance with the requirements of the Environmental Assessment Act.
Upper York/upper York Upper York is defined as the general area of York Region within the Lake Simcoe watershed.
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UYSS Service Area Area to be serviced by the proposed Undertaking consisting of the growth portions of the Towns of Aurora, Newmarket, and East Gwillimbury, including the communities of Holland Landing, Queensville, and Sharon.
Volatile solids Solids, primarily organic, that volatilize at temperatures equal to or exceeding 550°C.
Waste activated sludge Settled sludge in activated sludge treatment processes that is wasted from the biological treatment system to prevent the accumulation of solids in the system.
Wastewater Used water discharged from homes, businesses, cities, industry and agriculture.
Water Reclamation Centre A wastewater (sewage) treatment plant for treatment or processing of wastewater to make it reusable by meeting appropriate water quality criteria.
Water Quality Trading An approach to achieving water quality targets or objectives in which a point source may off-set with or purchase pollutant reduction credits from another point source in a defined geographic area (e.g., the same watershed) which can then be used to meet the point source’s discharge requirements for the same pollutant. Water quality trading will be further defined by regulations (rules, requirements, conditions, etc.) if enabled through regulation.
Watercourse A body of water having defined bed and banks with permanent or intermittent flow that may include rivers, creeks, streams, and springs.
Watersheds An area that is drained by a river and its tributaries.
Wetland Lands that are seasonally or permanently covered by shallow water, as well as lands where the water table is close to or at the surface. In either case the presence of abundant water has caused the formation of soils saturated with water and has favoured the dominance of either hydrophytic plants or water tolerant plants. The four major types of wetlands are swamps, marshes, bogs, and fens.
York Durham Sewage System (YDSS)
A centralized wastewater collection and treatment system for both York and Durham Regions.
Upper York Sewage Solutions Environmental Assessment
Technical Concept Level 2 Document Appendix A Water Reclamation Centre Design Prepared for: The Regional Municipality of York Prepared by:
JULY 2014 REF. NO. 050278 (81) YORK REGION NO. 74270
Conestoga-Rovers & Associates 1195 Stellar Drive, Unit 1 Newmarket, Ontario L3Y 7B8
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Table of Contents
Page
A.1 Process Selection A-1
A.2 Conventional Treatment A-2 2.1 Preliminary Treatment A-2 2.2 Primary Treatment A-3 2.3 Flow Balance A-5 2.4 Secondary Treatment A-6
A.3 Advanced Treatment A-9 3.1 Filtration for Reclaimed Water A-9 3.2 Microfiltration / Ultrafiltration (MF/UF) A-11 3.3 Reverse Osmosis A-12 3.4 Reverse Osmosis Permeate Post Conditioning A-13 3.5 Reverse Osmosis Concentrate Management A-16 3.6 Disinfection A-16 3.7 Dechlorination A-16
A.4 Solids Management A-18 4.1 Fermentation A-18 4.2 Biosolids Management Strategy A-20 4.3 Odour Control A-24
A.5 Site Work A-24 5.1 Landscaping A-24 5.2 Site Access A-24 5.3 External Utilities to Site A-25 5.4 On-Site Utilities A-26
5.4.1 Emergency Standby Power A-26 5.4.2 Sanitary Services A-26 5.4.3 Stormwater Management A-26
A.6 Operation and Maintenance Strategy A-27 6.1 Process Equipment Redundancy A-27 6.2 Connection to YDSS A-27 6.3 Compliance and Monitoring A-28 6.4 Staffing A-28
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Table of Contents
Page
List of Figures
Page
Figure A.1 Post Conditioning with MF Permeate Flow Balance A-14
List of Tables Page
Table A.1 Preliminary Treatment Process Design Criteria A-3 Table A.2 Primary Treatment Process Design Criteria A-4 Table A-3 Activated Sludge Process Design Criteria – Surface Water Discharge A-7 Table A.4 Activated Sludge Process Design Criteria – Reclaimed Water A-8 Table A.5 Activated Sludge Basin Dimensions (Preliminary) A-8 Table A.6 Secondary Clarifier Process Design Criteria A-8 Table A.7 Cloth Disc Filter Design A-10 Table A.8 Reverse Osmosis System Design A-12 Table A.9 Post Conditioning Chemical Use A-15 Table A.10 Post Aeration Process Design Criteria A-15 Table A.11 UV Disinfection Design Criteria A-16 Table A.12 Sodium Hypochlorite Use at Start-up and Future Flow
Conditions A-15 Table A.13 Reverse Osmosis Permeate Dechlorination with Sodium
Bisulfite A-16 Table A.14 Fermentation System Sizing A-19 Table A.15 Anaerobic Digestion Process Design Criteria A-22 Table A.16 Liquid Biosoilds Storage A-23
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A.1 Process Selection
For Technical Concept Level 1 Document, a preliminary concept of a treatment process was developed which could be used to treat the anticipated wastewater quantity and quality to meet the anticipated discharge and reuse criteria. The wastewater quantity and quality, as well as the discharge criteria were developed in Technical Concept Level 1 Document. To further develop treatment concept, a range of potential unit operations for each component of the treatment process was considered and the preferred approach selected. In order to allow for the most flexibility in the future regarding biosolids management, it was assumed that the biological process would be designed to accommodate both biosolids cake production and liquid biosolids. The following sustainability principles from York Region’s Water and Wastewater Sustainability Strategy, 2008, were used as the basis of comparison for the range of process options for the WRC: Maintain Healthy Watersheds Provide Full and Equitable Funding and Value for Money in Delivering Waster and
Wastewater Services Plan for Climate Change and Enhance Energy Efficiency
The principles were developed into wastewater treatment – related objectives which were used to compare the process design options:
Operating cost
Odour control
Nutrients for irrigation
Flexibility to accommodate potential changes in regulatory requirements for biosolids management
Capital Cost
Ability to phase
Flexibility to produce reclaimed water
Maximise potential for biogas production
Ability to respond to future nitrate discharge criteria
Since all of the short list sites met a minimum area available requirement of 15ha, footprint constraints were not considered in determining the preferred process.
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A.2 Conventional Treatment
The conventional treatment system consists of the following major treatment units: headworks, primary clarification, flow balancing, biological treatment and odour control. For each of these processes, several concepts or technologies were evaluated considering the criteria described in Section A.1. A.2.1 Preliminary Treatment
Raw wastewater would enter the Lake Simcoe Water Reclamation Centre headworks building via multiple force mains. Preliminary treatment would consist of fine screening and grit removal. A septage receiving station would be included at the headworks. Building air would be ventilated and treated for odour control. The selection of the unit operations in Preliminary Treatment is described below and summarized in Table A.1. Screening
Screens would be used to remove debris that could damage downstream equipment. Potential screen types include bar screens, drum screens, band screens, step screens, and screwpactors. Selection of screen type is deferred until preliminary design. Screens with 6-millimetre openings would be used to balance the potential for clogging with removal of solids that otherwise could cause downstream blockages. Initially, two mechanically-cleaned screens (6 mm openings) would be provided, each designed to handle half of the plant’s peak hourly flow. Also, one manually-cleaned bar rack (15 mm openings) would be installed to serve as a standby means of screening if one of the mechanically cleaned screens is out of service. Mechanically-collected screenings would be conveyed to a central location for washing/grinding and compaction. Two washer / compactor units would be provided for redundancy. Compacted screenings would be stored in a bin for landfill disposal. Truck access to the storage bin would be provided. Grit Removal
Grit removal would be provided at the headworks, to remove grit and sand that could damage downstream equipment such as primary sludge collectors, primary sludge pumps and digesters. Aerated grit removal, detritors (cross-flow), and vortex (mechanically or hydraulically induced) grit removal systems were considered for this application. Aerated grit removal was eliminated due to the increased potential for odour generation. Vortex grit chambers were selected over aerated and detritor grit removal due to their lower footprint
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and energy requirements. Mechanically-induced vortex systems are preferred over hydraulically-induced vortex due to better performance over a wide range of influent flows. Initially, two vortex grit units with bypass channel would be installed. Collected grit would be conveyed to a central location for washing and classification. Two washer/classifier units would be provided for redundancy, following best practices. Classified grit would be stored in a bin for landfill disposal. Truck access to the storage bin would be provided. Table A.1: Preliminary Treatment Process Design Criteria
Parameter Design
Design flows 40 MLD average 52 MLD max month 80 MLD max day 114 MLD peak hour
Incoming force mains 4 x 750 mm 4 x 450 mm
Screens 2 mechanical (6 mm) + 1 manual (15 mm) [57 MLD each]
Screenings processing 2 washers and 2 compactors Vortex grit units 2 x 4.9 m diameter + bypass
[57 MLD each] Grit processing 2 washers and 2 classifiers Flow measurement Parshall flume with 3-ft throat Septage unloading Included
A.2.2 Primary Treatment
Primary treatment processes separate settleable and floatable solids from raw wastewater, reducing the concentrations of TSS, BOD5, TKN, and TP in the process. Separated solids can be thickened in the liquid-stream treatment units to varying degrees depending on process design objectives. A wide range of primary clarification technologies were considered: conventional primary treatment, activated primary treatment, chemically enhanced primary treatment (CEPT), ballasted clarification (Actiflo®, Co-Mag®, and DensaDeg®) and dissolved air flotation (DAF). The recommended approach for the Lake Simcoe Water Reclamation Centre is to provide primary sedimentation basins that can be operated either in conventional primary treatment mode, or in CEPT mode. The Water Reclamation Centre concept is for treatment trains which can be operated for surface water discharge (with extremely low effluent TP) and for reclaimed water production for irrigation (where phosphorus in the effluent is advantageous for agronomic purposes). Therefore, a primary process that can be operated for greater phosphorus removal (in CEPT mode) or less phosphorus removal (in conventional mode) is preferable. CEPT also offers the advantage of additional primary solids capture, driving the organic loading to the
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digester or sludge incinerator (at Duffin Creek WPCP) leading to greater energy recovery and less energy required for aeration. Primary treatment would be configured such that each clarifier can operate in either CEPT or conventional primary treatment mode. One contiguous group of clarifiers would operate in conventional mode to produce water for reclamation. The other contiguous group would operate in CEPT mode to produce water for surface water discharge. Each clarifier would be preceded by dedicated tankage for rapid mixing and flocculation, collectively making a primary treatment train. When CEPT is used in a given train, ferric chloride would be added to the rapid mix tank. Iron salts are preferred over aluminum salts because of their ability to bind hydrogen sulfide (a potential source of odour) as well as orthophosphate. When conventional primary treatment is used, the rapid mix tank would be bypassed. As an alternative to bypass, primary influent could flow through the rapid mix compartment, and the mixer could be operated as required to re-suspend any settled material. Flocculation is beneficial to both CEPT and conventional primary treatment, so it would be used for either operating mode. Polymer must be fed for CEPT mode, and it would be optional for conventional primary treatment mode. The flocculation process would use two stages in series, and variable speed mixers would be used to optimize velocity gradients. Dilute polymer solution would be fed to wastewater entering the first stage. The rapid mix and flocculation tanks, and primary effluent weirs would be covered, and air would be withdrawn and directed to an odour control system. Table A.2 presents process design criteria for primary treatment facilities. The expected TSS removals shown would be used for plant design. Removals of other wastewater parameters, including BOD5, would depend on relative amounts of soluble and particulate fractions in primary influent, as modified by CEPT. Table A.2: Primary Treatment Process Design Criteria
Parameter Overall Reference (1)
Design flow rates 40 MLD average
80 MLD peak day
114 MLD peak hour
Number of trains CEPT/conventional primary treatment flow split is indeterminate. Because one train could be used to treat a small portion of the plant flow, primary treatment processes would be sized such that three of four trains can handle full flow.
Rapid mixing (each train)
38 MLD peak hour flow “Where separate mixing tanks are provided, they should be
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Parameter Overall Reference (1)
1 minute residence time
26.4 m3
3.0 m x 3.0 m x 3.0 m
equipped with mechanical mixing devices. The detention period should be at least 30 seconds.”
Flocculation (each train) 38 MLD peak hour flow
5 minute residence time
Two stages, each 66 m3
4.0 m x 4.0 m x 4.0 m
“The flocculation equipment should be adjustable in order to obtain optimum floc growth, control deposition of solids and prevent floc destruction.”
Clarification (each train) 330 m2
36.4 m x 9.1 m
13.3 MLD average flow
40 m3/m2/d average SOR
26.7 MLD peak day flow
81 m3/m2/d peak day SOR
length/width = 4
30-40 m3/m2/d average SOR
60-80 m3/m2/d peak day SOR
TSS removal 65% conventional
75% CEPT
40-70% (65% typical) without chemical addition
60-90% (85% typical) with chemical addition
1) MOE (2008) Design Guidelines for Sewage Works A.2.3 Flow Balancing
Flow balancing tanks would be located after primary clarifiers. The balancing tanks would serve two functions:
1. Dampen normal diurnal flow variations to maintain steady flow at annual average flow rate (40 MLD) to the downstream secondary, tertiary and reverse osmosis processes, and;
2. Reduce peak hour wet weather flow (114 MLD) to peak day flows (80 MLD), so that the secondary and tertiary treatment processes for the surface water discharge stream would not exceed design peak day flow.
The balancing tanks have two sections: one for diurnal flow balancing (9.2 ML), which would require multiple compartments, mixing to keep solids in suspension and odour control; and the
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other for wet weather peak flow balancing (5.25 ML). Since the wet weather section would not be a significant source of odour, only the diurnal section of the basins would be covered. A.2.4 Secondary Treatment
Secondary treatment would consist of bioreactors; in-basin diffusers, mixers, and pumps; secondary clarifiers; blower system; and pump systems for Return Activated Sludge (RAS), Nitrified Mixed Liquor Recycle (NRCY), Waste Activated Sludge (WAS), and secondary scum. For the 40 MLD plant construction, there would be four parallel bioreactors. The bioreactors would be configured such that one group of contiguous basins would provide treatment for surface water discharge, and the other group of contiguous basins would provide treatment for reclamation. Bioreactors for Surface Water Discharge
The group of bioreactors producing surface water discharge would receive effluent from the CEPT process. The CEPT process would be controlled such that CEPT effluent contains approximately 1 mg/L orthophosphate-phosphorus (PO4-P). Activated sludge treatment for surface water discharge would remove additional phosphorus, producing secondary effluent with approximately 0.15 mg/L PO4-P, the target for tertiary treatment design. Chemical phosphorus removal has been selected because it would produce a lower concentration of secondary effluent non-reactive soluble phosphorus, improving the plant’s ability to meet its stringent effluent TP limit, relative to biological phosphorus removal. In addition, there is the potential for biological phosphorus removal to increase the concentration of non-reactive phosphorus in the treated effluent. The activated sludge process for surface water discharge would be designed for complete nitrification and partial denitrification year-round. To accomplish nitrogen removal, the activated sludge process would be a four-stage Bardenpho process, consisting of the following zones: Pre-anoxic zone Oxic zone Post-anoxic zone Re-aeration zone
The pre- and post-anoxic zones would be mechanically mixed, and the oxic and re-aeration zones would be mixed and aerated using fine pore membrane disc diffusers. NRCY, containing nitrate and/or nitrite, would be pumped from the end of the oxic zone to the pre-anoxic zone, where denitrification would covert nitrate and nitrite to nitrogen gas. Denitrification, performed by certain heterotrophic bacteria, requires readily biodegradable COD (rbCOD). To supplement primary effluent rbCOD, primary sludge would be fermented, and fermentate would be directed to the pre-anoxic zone.
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Additional denitrification would occur in the post-anoxic zone. Nitrification depletes alkalinity, and denitrification restores a portion of this alkalinity. However, based on the anticipated wastewater characteristics, the net impact of nitrification/denitrification is such that an external alkalinity source would be needed to maintain near-neutral pH for biological treatment. Sodium hydroxide has been selected for Conceptual Design. Sodium hydroxide would be stored indoors in tanks. It would be fed using metering pumps to individual bioreactors (those being used to provide treatment upstream of river discharge). Table A.3 shows process design criteria for bioreactors used upstream of surface water discharge. Table A.3: Activated Sludge Process Design Criteria – Surface Water Discharge
Parameter Value Reference (1) Organic loading rate 0.13 kg BOD5/m
3/d (average) 0.20 kg BOD5/m
3/d (max month) 0.31-0.72 kg BOD5/m
3/d
Food to mass ratio (F/Mv) 0.080 d-1 (max month winter) 0.096 d-1 (average) 0.098 d-1 (max month summer)
0.05-0.15 d-1
Aerobic solids retention time (aSRT)
8 days at 10oC (winter) 8.4 days at 14oC (average) 10 days at 20oC (summer)
> 10 days at 5oC > 4 days at 20oC
Mixed liquor suspended solids (MLSS)
2,100 mg/L (average) 3,850 mg/L (maximum)
3,000-5,000 mg/L
(1) MOE (2008) Design Guidelines for Sewage Works Bioreactors for Reclaimed Water
The same activated sludge facilities would be used to produce secondary effluent either for surface water discharge or reclamation. The group of basins producing water for reclamation would receive effluent from the conventional primary treatment. For reclamation (i.e., irrigation), it is desirable to retain the nutrients nitrogen and phosphorus for their fertilizer value. Therefore, secondary treatment for reclamation would use high-rate treatment for BOD removal, while minimizing nitrification (conversion of ammonia to nitrite and nitrate). Table A.4 shows process design criteria for the bioreactors used to produce reclaimed water. It is noted that the design aSRT and MLSS are less than the values cited in the 2008 MOE Design Guidelines for non-nitrifying systems. However, for the purposes of producing a “nutrient rich” effluent to increase its value for reuse, the design criteria were selected to prevent any significant nitrification and therefore fall outside of the Design Guidelines. This would maintain, as much as possible, nitrogen in the ammonia form, increasing its value for fertilization.
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Table A.4: Activated Sludge Process Design Criteria – Reclaimed Water
Parameter Value Reference (1) Organic loading rate 0.35 kg BOD5/m
3/d (average) 0.52 kg BOD5/m
3/d (max month) 0.72-0.96 kg BOD5/m
3/d
Food to microorganism ratio (F/Mv)
0.63 d-1 (average) 0.96 d-1 (max month summer)
0.05-0.2 d-1
aerobic solids retention time (aSRT)
1.9 days at 14oC (average) 1.0 days at 20oC (summer)
4-6 days
Mixed liquor suspended solids (MLSS)
700 mg/L (average) 700 mg/L (maximum)
1,000-3,000 mg/L
(1) MOE (2008) Design Guidelines for Sewage Works Table A.5 shows preliminary sizing for the bioreactors. The same basins would be used to produce treated water for surface water discharge and reclamation. In reclaimed water mode, the pre-anoxic zone would not be used, and the post-anoxic zone would be aerated, converting it into part of the oxic zone. Table A.5: Activated Sludge Basin Dimensions (Preliminary)
Parameter Value
Pre-anoxic volume (each basin) 1,600 m3 Oxic volume (each basin) 3,200 m3 Post-anoxic volume (each basin) 1,600 m3 Re-aeration volume (each basin) 150 m3 Total volume (each basin) 6,550 m3 Number of basins 4 Total volume 26,200 m3 Water depth 5.5 m Surface area (each basin) 1,190 m2 Length (each basin) 85 m Width (each basin) 14 m
Secondary Clarifiers
For the 40-MLD plant construction, there would be four secondary clarifiers. The bioreactors and clarifiers would be configured with the flexibility to connect any number of clarifiers to the “surface water discharge” and “reclaimed water” bioreactors. Table A.6 presents process design criteria for the secondary clarifiers. Table A.6: Secondary Clarifier Process Design Criteria
Parameter Value Reference (1) Number 4 Diameter 32 m Sidewater depth 4.6 m 3.6-4.6 m Peak hour surface overflow rate (2) 27 m3/m2/d 37 m3/m2/d (chemical P removal) Peak day solids loading rate 162 kg/m2/d 170 kg/m2/d (single-stage nitrification)
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(1) MOE (2008) Design Guidelines for Sewage Works (2) Secondary clarification is downstream of equalization. Design peak day and peak hour secondary effluent flows are the same.
A.2.5 Odour Control As described above, air would be withdrawn from critical areas in the Preliminary Treatment, Primary Treatment and Flow Balancing processes and treated to prevent off-site air quality impacts. The following odour control technologies for the conventional treatment at the Water Reclamation Centre were considered: Biofilters Biofilters can treat both Hydrogen Sulfide (H2S) and Volatile Organic Compounds (VOCs). These systems are robust, and can take higher organic loading than carbon filters. Biofilters are low profile (typically less than 2 metres of media depth), but have a large footprint. These can be covered or uncovered. Covering the filters provides cold weather protection and makes it possible to add a stack for discharge if desired based on air dispersion modeling. However, cost of a cover can be as much as half the cost of the actual biofilter. Biotowers Biotowers contain plastic media, on which H2S-removing bacteria grow. These are used to treat high levels of H2S; however, they do not remove VOCs. Since they do not remove VOCs, there is typically a need to add carbon systems for polishing when used in wastewater plant applications. Biotowers can be used in either single- or dual-chamber vertical configuration. Single-chamber units are typically approximately 5 metres in height. Dual chamber units, which accomplish the same treatment within a smaller footprint, are approximately 9 metres tall. Carbon Systems Activated carbon filters are effective at removing VOCs within a small footprint, but are not effective in removing H2S. Single-chamber carbon filters typically have a height of 3-4 metres; dual-chamber units typically have a height of 4-5 metres. For the purposes of the site selection, biofilter technology has been allowed for all sources in order to ensure adequate space for this process because it comprises the biggest footprint of all alternatives. The headworks, primary clarifier weirs and balancing tank may use a combination of a biotower and activated carbon instead. Biofilters can be constructed with or without a stack to improve dispersion. Final selection of the preferred technology will be undertaken during Preliminary Design.
A.3 Advanced Treatment
The advanced treatment system has two treatment trains, one for producing effluent for surface water discharge and one for reclaimed water. The treatment train producing effluent for discharge includes the following major treatment units: filtration, reverse osmosis, post conditioning of the effluent, RO concentrate management and disinfection. For production of reclaimed water, the major advanced treatment units used are filtration and disinfection.
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This section describes the concept and technology options assessed for each of the major process units and documents the selection of the concept or technology selected. A.3.1 Filtration for Reclaimed Water
At the Concept Level 1 stage of the process development, the intent was to use the same tertiary filtration system for both the Surface Water Discharge and Reclaimed Water treatment trains. However, upon further investigation, membrane manufacturers indicated that the characteristics of the biomass generated by a short SRT system required to maintain the nitrogen in ammonia form are not compatible with their equipment. Membrane manufacturers will not guarantee operation at short solids retention times because of how rapidly and how strongly the young short age biomass fouls the membrane surfaces. Instead, cloth disc filters were selected to produce high quality reclaimed water. This technology can meet the required performance at a lower capital cost than sand filters and is more modular so it can be better sized to the reclaimed water demand. The filters would be installed in a separate filter building and would include administrative and some storage space. The cloth disc filter uses a cloth membrane (random weave fabric) as the filter medium. The density and thickness of the filter cloth is selected according to the characteristics of the influent wastewater and desired effluent quality. The disks covered by the cloth membrane are mounted vertically to a common hollow tube. Wastewater passes from the outside through the cloth membrane by gravity and enters inside the filter discs. The filtered effluent is conveyed through the hollow tube to an effluent channel which conveys the reclaimed water to disinfection. As the filter continues to operate over time, the headloss builds up as accumulated solids collect on the surface of the membrane. The backwash operation of the filter media is based either on headloss or accumulated filtration time. A backwash vacuum shoe is mounted on each side of each disk as the disk rotates past the shoe the cumulative solids are vacuumed from the media. The water that is used to clean the media is continuously supplied by a pump from the filtrate produced by the cloth disc filter. The filter is thus always in operation. Table A.7 presents design criteria for the cloth disc filters. Table A.7: Cloth Disc Filter Design
Parameter 2031
Assumed influent TSS (mg/L) 15
Assumes no pre conditioning chemical feed (alum or Iron)
-
Minimum design flow (MLD) 4
Maximum design flow (MLD) 30
Effluent NTU Limit 2
Headloss across filters (Metres) 0.3
Average filtration rate (L/min/SqM) 35
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Parameter 2031
Peak filtration rate (L/min/SqM) 70
Number of filters (disks per Unit) 8
Number of Units 4
Note: Based on Aqua-Aerobics Systems Inc. (facility to be designed around selected vendor equipment). A.3.2 Microfiltration / Ultrafiltration (MF/UF) Treatment using sand or cloth filters alone is not adequate when the water would need to be further treated by RO. The feed water to the RO system should be characterized by consistently low turbidity, and colloids concentration. To achieve consistently high quality feed water, use of MF/UF processes upstream of RO is essential and has become a standard practice in many reclamation facilities. Enhanced tertiary clarification or sand filters followed by MF/UF were considered. This would offer:
The potential use of the sand filters for reclaimed water production as well as surface
water discharge treatment More phosphorus removal prior to RO with the potential to meet the discharge
requirements with only a portion of the flow treated with RO Lower operating cost than MF/UF alone
Tertiary clarification or sand filters prior to MF/UF were eventually eliminated from further consideration because of the higher capital cost and larger footprint compared with dedicated cloth disc filters for reclaimed water production. In addition, removal of the majority of the phosphorus with a combined sand filter + MF/UF in order to reduce the size or volume processed by the RO system would not likely be acceptable to the MOE without extensive testing. The only significant difference between the MF and UF systems is the particle size cutoff by the membranes. Either system provides good pretreatment ahead of RO. The MF/UF membrane is intended to remove particulate matter including precipitated phosphorus. By removing the suspended and colloidal solids from the treated wastewater, the MF/UF protects the RO system from excessive fouling from particulate matter. The selection between a pressurized and gravity system (“pump to” versus “pump from”) will be carried out at a later stage of design. MF/UF facilities are typically designed based on a preselected vendor’s system. Mesh strainers (0.5 mm) are required prior to the MF/UF system. The RO system is susceptible to biological growth and the associated biofouling. Addition of a biocide is necessary for long term operation of this membrane system. Chloramine is a very good biocide and a very weak oxidant so monochloramine does not damage the membranes typically used in water and wastewater applications.
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While anti-biofouling agents are not always used with MF/ UF systems, because it is required for the RO system, there is an advantage to adding the anti-biofouling agent upstream of the MF/UF system. Chloramine addition at the MF/UF system would provide biocide protection for both membrane systems. A.3.3 Reverse Osmosis
The RO system is included in the process train as the final step for phosphorus removal. The RO membranes would remove any remaining reactive (ortho phosphate) phosphorus not removed by chemical precipitation. The RO would also remove any non-reactive phosphorus (phosphorus bound into organic molecules or into phosphorus complexes that will not react with chemical coagulants and precipitate) remaining in solution. The RO system design details are shown in Table A.8 Table A.8: Reverse Osmosis System Design
Parameter Value
Maximum Month Design Flow (MLD) 52
Annual Average Design Flow (MLD) 40
Design Recovery Rate (%) 85
Design Flux Rate Range (L/m2/hr) 407 – 488 (10-12 gfd)
Number of Stages 3
Number of Trains 4
Train Flow Capacity (MLD) 13
The RO system would include facilities for flushing the RO trains and a clean in place (CIP) system. The CIP system would include tanks for chemical cleaning of the RO membranes. As discussed in the previous section, the RO system requires an anti-biofouling agent. Chloramine would be used as the anti-biofouling agent. The RO system also requires the use of an anti-scalant. The anti-scalant sequesters sparingly soluble salts and allows operation of RO at concentrations higher than their saturation limits. The common sparingly soluble salts are calcium sulfate, calcium carbonate, calcium fluoride, calcium phosphate, silica, barium sulfate, strontium sulfate, etc. Addition of acid may also be required to control carbonate scale and to optimize antiscalant dose. Scale formation would rapidly foul the membranes and in some instants (such as sulfate or silica scale), may damage the membranes irreversibly. An RO feed tank would be placed between the MF/UF system and the RO system (255m2 each, 510 m2 total). This surge tank would provide a wide spot in the line to allow RO trains to be brought into service or to be taken out of service.
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As with the MF/UF system, the balancing tanks ahead of the secondary biological process insulate the RO system from sudden changes in wastewater plant influent flow. The balancing tanks allow fewer banks of RO vessels to be installed. The number of trains will be finalized during Preliminary Design. The RO feed tanks also improve chemical addition control around the RO. The anti-scalant feed system would be flow paced. With influent equalization, anti-scalant addition would be easier to control and the delivered dose to the RO would be more consistent and reliable. A.3.4 Reverse Osmosis Permeate Post Conditioning
The use of RO typically requires a series of post-conditioning processes to be included to stabilize the RO permeate (product water). Stabilization is required to produce product water that is non-toxic to aquatic life, as well as to prevent corrosion of the discharge conveyance system. Alkalinity is a measure of the amount of base compounds such as carbonates and bicarbonates and is an indication of the ability of the water to buffer changes in pH. Hardness is a measure of the divalent salts present such as calcium and magnesium. RO permeate has low alkalinity and hardness, and frequently has a low pH as a result of acid often added to control RO scaling and low alkalinity and hardness due to removal of dissolved materials.
With depressed pH and virtually no alkalinity or hardness remaining, it is anticipated that the RO permeate would be toxic to aquatic life and corrosive to metal and concrete. For example, calcium is essential in biological processes (i.e. bone/scale formation) and plays a key role in osmoregulation (maintaining precise levels of internal salts). Although some aquatic life can tolerate a range of pH, alkalinity and hardness, sensitive species may be adversely affected Stabilization processes include addition of dissolved solids to replace alkalinity and hardness removed by the RO process, pH adjustment if required, post aeration to increase dissolved oxygen levels and temperature modification to approach the temperature of the discharge water body if the two temperatures are significantly different. Addition of Dissolved Solids
Restoration of the hardness and alkalinity in the RO permeate can be achieved by chemical addition (such as lime, or other calcium-containing materials) or blending with another water product. The following three approaches have been considered:
1. Returning a portion of the RO concentrate to the RO permeate;
2. Bypassing a portion of the Low Pressure Membrane permeate (microfiltration (MF) permeate) around the RO system; and
3. Chemical conditioning.
While the long-term objective for York Region is to treat the RO concentrate for phosphorus and blend it back with the RO permeate, during the initial stage the RO concentrate would be sent to
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the YDSS for treatment at Duffin Creek WPCP. Therefore RO concentrate re-blending would not be an option for use in RO permeate post conditioning at Water Reclamation Centre start-up. Post conditioning of the RO permeate with MF permeate and chemicals are being investigated using treated effluent generated the Mount Albert Demonstration Facility. The preferred approach is to use MF permeate to provide in the appropriate concentration of hardness. Some MF product would bypass the RO and be blended with the RO permeate. MF permeate has the hardness needed for conditioning the RO permeate and is low in phosphorus. A mass balance was performed to determine the amount of MF permeate needed to achieve 40 mg/L hardness in the RO permeate. Based upon an average flow of 40 MLD to the RO, the mass balance shows that up to 3.7 MLD of MF permeate would be needed for blending with 30.9 MLD of RO permeate to produce a blended RO permeate with 40 mg/L hardness. The flow balance is shown in Figure A.1. Figure A.1: Post Conditioning with MF Permeate Flow Balance
The second approach is to add chemicals to the RO permeate to adjust RO permeate hardness. At this time it has been assumed that a40 mg/L hardness and 40 mg/L alkalinity concentration (both reported as CaCO3) are needed. The calcium chloride and soda ash have been tested for phosphorus and both have negligible phosphorus concentrations. For a 40 MLD Water Reclamation Centre design of flow to the RO and an 85% water recovery rate the following mass use of conditioning chemicals are shown in Table A.9.
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Table A.9: Post Conditioning Chemical Use
Parameter Start-up Average Design Flow
Maximum Month Design Flow
Flow (MLD) 10 40 52
Calcium Chloride (kg/d) 400 1,600 2,080
Sodium Carbonate (kg/d) 430 1,720 2,236
Carbon Dioxide (kd/g) 120 480 624
Note: Chemical addition based on producing 40 mg/L hardness and 40 mg/L alkalinity concentration in the RO permeate. The preferred alternative will be selected during Preliminary Design. Post Aeration
Treated effluent for surface water discharge would need to be aerated to boost oxygen concentration from June through October. As the Water Reclamation Centre site has not been selected at this stage and site topography is uncertain, diffused post aeration is assumed. The diffused post aeration process would use two parallel basins such that peak oxygen transfer requirements could be met with both basins in service, while average oxygen transfer requirements could be met with one basin out of service. It is assumed that 230 mm (9 inch) diameter membrane disc diffusers would be used. Table A.10 shows the post aeration process design criteria. Table A.10: Post Aeration Process Design Criteria
Parameter Value
Design peak flow (MLD) 80
Incoming DO (mg/L) 0.0
Target DO (mg/L) 5.0
Actual oxygen transfer rate (kg/re) 17
Retention time at peak flow (minutes) 5
Volume (total) (m3) 280
Number of basins 2
Volume (per basin) (m3) 140
Water depth (m) 5.5
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Parameter Value
Surface area (m2) 24.5
Width (per basin) (m) 3.6
Length (per basin ) (m) 7.1
Number of diffusers (per basin) 50
Tank floor area/diffuser area (AT/AD) 13
A.3.5 Reverse Osmosis Concentrate Management
The RO concentrate would contain a mixture of soluble reactive and nonreactive phosphorus compounds. The purpose of the RO concentrate treatment system is to convert more nonreactive phosphorus (nRP) into a form of phosphorus that can be precipitated. Initially the RO concentrate would be discharged to the YDSS, as these sewer lines have capacity for the RO concentrate until 2031. This is an interim solution as the goal is to keep the RO concentrate stream in the watershed. Additional research is ongoing to define the RO concentrate treatment process. RO concentrate management has been divided into five phases for implementation: Initial discharge to the YDSS; RO concentrate treatment bench-scale investigation; RO concentrate demonstration testing; RO concentrate system design; and Full-scale RO concentrate treatment.
York Region has confirmed the capacity of the YDSS to accept up to 12 MLD of RO concentrate through to 2031 provided that a minimum of 24 hours off-line storage is available under wet weather conditions when the YDSS capacity is constrained. A.3.6 Disinfection
Disinfection is required for surface water discharge (100 Fecal Coliform MPN/ 100 mL) and for reclaimed water use (2 Fecal Coliform MPN/ 100 mL). UV was selected for use in the Water Reclamation Centre in place of chlorine for disinfection due to the large basin volumes associated with minimum chlorine contact times for the reclaimed water. Very limited UV treatment is required for MF/UF and RO treated effluents. The UV disinfection criteria used to size the UV reactors is shown in Table A.11. Table A.11: UV Disinfection Design Criteria
Parameter Value
Reclaimed Water Treatment
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Parameter Value
Permit Limit 2 fecal coliform MPN/ 100 mL
UV Transmittance (% UVT) 55
UV Dose (mJ/cm2) 100
Surface Water Discharge
Permit Limit 100 fecal coliform MPN/ 100 mL
UV Transmittance (% UVT) 95
UV Dose (mJ/cm2) 30
UV disinfection may be in-vessel or in-channel. The selection of the preferred approach is dependent on the overall hydraulic profile for the process and will be selected during Preliminary Design. Reclaimed water has a second disinfection criteria as the water must maintain a total chlorine residual of 1 mg/L to the end of the distribution pipe. Since the reclaimed water would be pumped to the off-site locations, chlorine would be added upstream of the pump station. Addition of sodium hypochlorite will form monochloramine. Chloramines are quite stable and are not as reactive for general oxidation as free chlorine so maintaining a 1 mg/L residual at the end of the pipe would be much easier to control. However, even chloramines decay so the initial dose should be based upon a 2 mg/L as Cl2. Table A.12 shows the projected doses for sodium hypochlorite under start-up and future flow conditions. Table A.12: Sodium Hypochlorite use at Start-up and Future Flow Conditions
Parameter Value
Start-up Conditions
Flow (MLD) 4
1 mg/L residual chlorine initial dose (kg/d) 4.25
2 mg/L residual chlorine initial dose (kg/d) 8.51
Design Average Flow, 40 MLD
Flow (MLD) 30
1 mg/L residual chlorine initial dose (kg/d) 31.9
2 mg/L residual chlorine initial dose (kg/d) 63.8
A.3.7 Dechlorination Dechlorination is required following RO treatment to meet the chlorine residual discharge requirement and avoid aquatic toxicity.
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Sodium bisulfite addition is the standard in the industry, a commonly used reducing agent to dechlorinate wastewaters. Since the allowable residual chlorine concentration is low (0.02 mg/L as Cl2), addition of about 10% excess bisulfate is needed to ensure that all of the chloramine is dechlorinated. The reaction between sodium bisulfite and chloramine is nearly instantaneous so a short retention time contact is needed to allow the reaction to completion. Table A.13 shows the reverse osmosis permeate dechlorination with sodium bisulfite. Table A.13: Reverse Osmosis Permeate Dechlorination with Sodium Bisulfite
Parameter Start-up Average Design Flow
Maximum Month Design Flow
Flow (MLD) 10 40 52
Sodium Bisulphite (kg/d) 33 (33)(1) 130 (132) 156 (172)
(1) Value in parenthesis is the stoichiometric dose plus 10% excess chemical to ensure complete dechlorination.
A.4 Solids Management The solids management system would handle solids from the primary clarifiers and waste activated sludge from the secondary clarifiers for eventual disposal off-site. This section describes the concept and technology options assessed for management of the biosolids generated at the Water Reclamation Centre. A.4.1 Fermentation BioWin process modeling, a commercial biological process simulator, was performed on the activated sludge process; modeling results are shown in Appendix B. The modeling identified a need for additional carbon to denitrify to achieve below 10 mg/L nitrate as N in the effluent. The primary effluent BOD to N ratio in the anticipated wastewater indicates that enough carbon is present for effective denitrification but most of the BOD is associated with VSS and that takes time to be hydrolyzed and available for denitrification. CEPT does not affect the removal of soluble BOD. Since there is no Water Reclamation Centre influent to sample at this time, it has been necessary to make assumptions pertaining to the influent wastewater characteristics. The raw wastewater characteristics as defined in the Water Reclamation Centre Design Basis Report were used; however the Basis of Design report does not break down the influent characteristics into the form that is needed for Biowin. The influent characterization assumptions made were conservative and assume that little fermentation occurs in the collection system so the soluble BOD and COD fractions are low representative of fresh sewage. Two types of fermenters were evaluated; a MLSS fermenter and a primary sludge fermenter. Only the primary sludge fermenter produced enough soluble biodegradable material for the process model to get to the target effluent nitrate concentration.
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The primary sludge fermenter was selected. The fermenter was modeled to have a 48 hour retention time. During that time frame, VSS would be hydrolyzed anaerobically into soluble material, some of which would be fermented to volatile fatty acids. The more readily biodegradable material present in the feed to the anoxic zone, the faster denitrification will occur. The high influent TKN concentration affects the denitrification design. The high influent TKN concentration is why additional soluble biodegradable material is needed in the anoxic zone. The primary sludge fermentation system shall consist of the following components: Tank Elutriation water supply, secondary effluent Top entering mechanical mixer Gravity thickener with cover Feed pumps, variable speed Thickened sludge pumps Headspace gas monitoring for H2S and methane Gravity thickener overflow Tank overflow weir for scum removal Gravity thickener overflow pump station Water spray system to facilitate removal/ transport of scum to weir Gravity Thickener return flow lines and flow distribution control to the nutrient removal
side of the plant The initial sizing information on the fermenter is shown in Table A.14 Table A.14: Fermentation System Sizing
Parameter Value
Number of Fermenters 2
Total Volume (m3) 1,320
Volume per Fermenter (m3) 660
Side Water Depth (m) 8
Width (m) 9.1
Length (m) 9.1
Maximum Primary sludge pumping to fermenter (Lpm per fermenter) (variable speed drive)
230
Maximum Fermenter effluent sludge pumps (Lpm per fermenter) (variable speed drive)
230
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Elutriation water is needed to blend in with the fermented sludge prior to entering the gravity thickener. A variable delivery of elutriation water flow of up to 415 Lpm is needed to address the range of flows to the facility. A.4.2 Biosolids Management Strategy As previously noted, in order to allow for the most future flexibility regarding biosolids management, it was assumed that the biological process would be designed to accommodate both biosolids cake production and liquid biosolids. Four options were included in the development of the Conceptual Design at the Alternative Methods stage: Biosolids Option A: Sending raw primary sludge and waste activated sludge via the
YDSS to Duffin Creek WPCP for processing Biosolids Option B: Trucking thickened biosolids to Duffin Creek WPCP for processing. Biosolids Option C: Storing anaerobically digested liquid biosolids on site, followed by
seasonal land application of the liquid biosolids, and Biosolids Option D: Dewatering anaerobically digested sludge on site, followed by land
application of the dewatered biosolids
Each is discussed in further detail below. Option A: Transfer to YDSS with RO Concentrate
Option A would be used at the startup of the Water Reclamation Centre. RO concentrate and solids streams would be pumped from the Water Reclamation Centre to the YDSS for further treatment at the Duffin Creek WPCP. Option B: Thicken and Truck to Duffin Creek WPCP
While not foreseen at this time, if for any reason the biosolids cannot be conveyed to the Duffin Creek WPCP through the YDSS, they can be thickened and transported by truck. This method is used by the other wastewater treatment plants in upper York. Sludge thickness would affect size of digesters and winter storage. If thickness is low then secondary digesters would need to be decanted and the nutrient laden supernatant would return to the treatment plant – not a desirable outcome, therefore it is preferable to thicken the sludge. Thickened sludge would also mean smaller digesters. Thickening of the primary sludge using a gravity thickener is included in the fermentation process described in Section 3.5.1. For the waste activated sludge, the following thickening methods were considered: rotary drum thickeners (RDT), gravity belt thickeners (GBT) and centrifuges. RDT was identified as the preferred alternative because it has better odour control ability than the GBT (which would need to be vented to an odour control system) and is simpler to operate and less expensive than a
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centrifuge. An RDT can run unattended. The system would be sized with a sludge blending tank with 4 hours retention before entering RDT which would be sized for 24/7 operation. Co-thickening of primary and secondary sludges in the primary clarifier was discounted due to the potential to solubilise BOD and create odours. Option C: Digest, Thicken and Liquid Storage for Beneficial Reuse
Option C builds on the infrastructure for Option B. The biosolids stabilization process would receive thickened primary sludge (~4 percent total solids) and thickened waste activated sludge (~4 percent total solids). Offsite waste streams (e.g., treatment plant biosolids or restaurant grease) would not be accepted at Lake Simcoe Water Reclamation Centre. Septage would be introduced to liquid-stream treatment at the headworks, not to the biosolids stabilization process. Following thickening of the primary sludge and Waste Activated Sludge (WAS) two approaches were considered for biosolids stabilization: Aerobic digestion Anaerobic digestion
Selection of the biosolids stabilization process was made in tandem with selection of primary and secondary treatment processes. Given the decision to include primary treatment, and specifically to use CEPT to maximize energy directed to the stabilization process, it would not make sense from an energy standpoint to use aerobic digestion. In “Design Guidelines for Sewage Works,” MOE writes, “Anaerobic mesophilic digestion is the most commonly used process for the digestion of primary and mixtures of primary and waste secondary treatment sludges (e.g., waste activated sludge), particularly at larger plants.” For these reasons, anaerobic digestion is selected. An anaerobic digestion process can be designed to operate at mesophilic (~35oC) or thermophilic (~55oC) temperature. Thermophilic digesters would require more energy for digester heating, and incremental capital cost would result from digester insulation and heating systems. However, thermophilic digesters would achieve greater volatile solids destruction and biogas production and would be capable of producing “Class A” biosolids. For Lake Simcoe Water Reclamation Centre, “Class A” biosolids is not considered to be a significant advantage as the capital cost is higher and there is no regulatory recognition of “Class A” biosolids in the Province of Ontario. Therefore, mesophilic anaerobic digestion would be used. In “Design Guidelines for Sewage Works,” MOE writes the following about mesophilic anaerobic digestion in Ontario: “Two-stage mesophilic anaerobic digestion has typically been practiced at larger STPs in Ontario. This arrangement with primary and secondary digesters is considered to be high-rate digestion, consisting of a heated and mixed primary digester and an unheated and unmixed secondary digester.”
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Lake Simcoe Water Reclamation Centre would use two-stage, high-rate mesophilic anaerobic digestion. For design conditions (2031), two primary digesters and one secondary digester would be constructed. The buildout conditions establish the volume per digester, as shown below in Table A.15. Primary digester volume is based on MOE guidelines for volatile solids loading rate and hydraulic retention time (HRT), applied under design maximum monthly-average influent loads and minimum monthly-average biological process temperature. Digester feed flows and loads were determined using BioWin. Two Water Reclamation Centre operating scenarios were considered, one with 100 percent of treated effluent directed to the river, and the other with 75 percent of treated effluent directed to irrigation and 25 percent of treated effluent directed to the river. Higher digester feed flow and loads would occur in the latter case. With one primary digester out of service under annual average conditions, and digester feed at 4 percent total solids, digester HRT would be 20 days (design) or 23 days (buildout). This meets the 15-day HRT requirement for land application. With one primary digester out of service under maximum monthly-average conditions, and digester feed at 4 percent total solids, digester HRT would be 11 days (design) or 13 days (buildout). To meet the HRT requirement for land application, it would be necessary to increase digester feed from 4 to 5.5 percent total solids (design) or 4.6 percent (buildout). These concentrations can be achieved by careful operation of the thickening processes selected. The unheated secondary digester would be the same volume as one heated primary digester. Table A.15: Anaerobic Digestion Process Design Criteria
Parameter Design Reference1
Primary digester volume (each) 5,500 m3 Secondary digesters…should not be credited in the calculations for volumes required for sludge digestion.
Number of primary digesters 2
Primary digester volume (total) 11,000 m3
Primary digester feed volatile solids load (maximum monthly-average)
15,200 kg/d For digestion systems providing for intimate and effective mixing of the digester contents, the system may be loaded up to 1.6 kg/m3/d of volatile solids in the active primary digestion units.
Primary digester volatile solids loading rate (maximum monthly-average)
1.4 kg/ m3/d
Primary digester feed flow rate (maximum monthly-average)
500 m3/d The nominal minimum hydraulic retention time (HRT) in the primary digester should be at least 15 days.
Primary digester hydraulic retention time (maximum monthly average)
22 days
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Parameter Design Reference1
Number of secondary digesters 1
Secondary digester volume 5,500 m3
Primary and Secondary Digesters
Sidewater depth 15.0 m
Diameter (inside) 21.6 m
Sidewater depth to diameter ratio 0.7
Sidewall depth-to-diameter ratio typically ranges from 0.3 to 0.7
(1) MOE (2008) Design Guidelines for Sewage Works This option also includes storage of liquid biosolids prior to land application. Ontario guidelines suggest 240-days (8 months) storage required for liquid sludge. Storage calculated was based on annual average conditions for the surface water discharge operation (CEPT, nitrification-denitrification) and the reclaimed water operation (short SRT producing more solids). The storage required is provided in Table A.16. In general, 8 months storage is not necessary in Southern Ontario as the non-application period is shorter than in other parts of the province. The volume for 5 months storage is also shown. The decision regarding the required storage will be made during Preliminary Design. Table A.16: Liquid Biosolids Storage
Storage No. of Tanks Diameter Sludge Depth
8 months 6 30 m 16.7 m
5 months 6 30 m 10 m
These volumes calculated assuming sludge reduction from 3.5% to 5.0%. Option D: Thicken, Digest and Dewater
For this option, belt filter presses were assumed for dewatering the digested biosolids. Biosolids in this form can be used for land application, sent to landfill or hauled to Dufferin Creek and incinerated. An enclosed truck loading facility would be used to load the trucks for haulage offsite. Minimal storage in the truck loading bins (approximately 4 days) would be provided. Dewatering filtrate flow equalisation would be required for this option. Depending on the actual wastewater characteristics, an additional treatment step may be desirable to treat any filtrate from the solids handling process before returning to the liquid treatment system. Processes may include phosphorus recovery, nitrogen control, and a proprietary process to remove struvite.
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Sidestream treatment for nitrogen removal could be used to reduce the Water Reclamation Centre electrical energy use. A.4.3 Odour Control
As previously described in Section 3.3.1.5, the Water Reclamation Centre will be designed for no off-site air quality impacts; odour control will be integral to the design of the facility. The sludge processing/storage areas could include gravity thickeners, rotary drum thickeners, digesters, liquid sludge storage tanks, dewatering and truck loading. Sludge processing/storage areas would be located in close proximity so that a single odour control system can be used to treat air from all of these sources. An odour control system for these areas would be designed to treat the compounds anticipated from each specific process. At this time, biofilter technology has been allowed for all sources, which comprises the biggest footprint of all alternatives, in order to ensure adequate space for this process. A.5 Site Works
A.5.1 Landscaping The Lake Simcoe Water Reclamation Centre would be provided with screening from adjacent properties using berms and planted native species. A.5.2 Site Access Vehicular traffic to the Water Reclamation Centre Site would include cars and light trucks for staff, commercial trucks for the delivery of goods and consumables and commercial haulage trucks for the removal of biosolids. Ideally, the Water Reclamation Centre Site layout would have two vehicle access points: one for staff and visitors, which should provide access to the Administration Building, and a second entrance for service vehicles, which should provide service vehicles with access to the required wastewater treatment infrastructure and buildings via the on-site access roads. The entrances to the Site should be located such that motorists have a clear line of sight in both directions, in order to safely enter and exit the Water Reclamation Centre facility. It is desirable to have the on-site roads looped in order to make the Site easier for large service vehicles to navigate, and to ensure that service vehicles have access to all relevant wastewater treatment infrastructure flow of traffic. For safety and the layout of roadways on the site the need for large trucks to have to back up should be limited or eliminated. The access road for the Water Reclamation Centre Site needs to be of a suitable standard to accommodate large service vehicles or be upgraded accordingly for the dimensions and loadings associated with the service vehicles.
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A.5.3 External Utilities to Site
For the Water Reclamation Centre to operate a number of external utilities would be required. These include electrical power, natural gas, telecommunications and potable water. Electrical Power The preliminary calculation of power load requirements for the Water Reclamation Centre Facility is approximately 2,200 kW. This is comparable to similarly sized existing wastewater treatment facilities and advanced water treatment facilities. The peak load used for the service sizing was taken as 3,000 kW. Based on this, the Water Reclamation Centre’s electrical system would likely be designed with two 2,000 kVA transformers. The utility provider for electrical power at all five potential Water Reclamation Centre locations is Hydro One. Hydro One has advised that to provide power to a 2,000 kVA transformer, a 44 kV feed is required. In the proposed area of the Water Reclamation Centre, Hydro One currently has 44 kV lines on 2nd Concession as far north as Queensville Side Road, on Queensville Side Road between 2nd Concession and Leslie Street, and on Leslie Street between Queensville Side Road and Holborn Road. Natural Gas Typically when available, natural gas is used for the heating of the primary digesters and to provide heating for buildings. The preliminary calculation of heat load for raising and maintaining the sludge temperature in the digesters is approximately 1.1 MBTUH under winter conditions. The preliminary calculation for building heating requirements with gas heating is approximately 5.1 MBTUH. Using an energy content of natural gas of 1,000 BTU/cu.ft, and an efficiency of 90%, the peak gas requirement for the Water Reclamation Centre is approximately 7,000 cfh. The utility provider for natural gas in the area of the Water Reclamation Centre is Enbridge. Enbridge currently has natural gas lines on 2nd Concession as far north as Algonquin Forest Drive and on Leslie Street between Queensville Side Road and Holborn Road. Telecommunications Phone and internet services would be required at the Water Reclamation Centre site to allow for operator communication. SCADA communications would be handled on the York Region’s own fibre network (York Telecom Network, YTN) which currently links many of their main sites. There is currently no YTN fibre in the areas of the 5 potential Water Reclamation Centre sites, however York Region has a project underway that would bring fibre to the proposed new pumping stations at Holland Landing, 2nd Concession and Queensville West in 2015 and Queensville East in 2018. They also plan to run YTN fibre to the final selected Water Reclamation Centre site in 2018.
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Potable Water Potable water would be required at the Water Reclamation Centre site to provide drinking water and water for washrooms, and other general uses requiring potable water. In addition, the potable water supply would be used to provide water for fire protection. The assumed branch connection size required to supply the site potable water needs is 200 mm. In the proposed area of the Water Reclamation Centre, the Town of East Gwillimbury currently has a 250 mm diameter watermain on Leslie Street to approximately 800 metres north of Queensville Side Road. There are no existing watermains on 2nd Concession or Queensville Side Road. A new York Region water distribution main would be installed on 2nd Concession as part of the QHLS Wastewater Servicing Project. Site service water for other applications (e.g. equipment cleaning) would be drawing from the treated effluent. A.5.4 On-Site Utilities A.5.4.1 Emergency Standby Power The Water Reclamation Centre would include an emergency standby power generating facility to provide power for continued operation of all critical treatment processes. During a power outage the standby power generators would automatically start and the power feed to the Water Reclamation Centre would be automatically switched to the on-site power supply. The generators would have minimum quantity of fuel to allow for 24 hours of operation. If a power outage extends beyond 24 hours then fuel can be delivered to the facility to allow the generators to run for an extended period of time if required. When the power outage is over the standby generators would shut-down and power supply would return to the normal power feed from Hydro One. A.5.4.2 Sanitary Services The Water Reclamation Centre would treat all wastewater that is generated at the facility. Sanitary wastewater from each of the buildings at the Water Reclamation Centre would be connected to a local gravity sanitary sewer collection system. In addition this sewer would also receive discharges from building sumps in processing areas. The gravity sewer would drain to a central pumping station which would discharge all wastewater collected on-site to the headworks treatment facility. A.5.4.3 Stormwater Management Stormwater management ponds would be incorporated into the site landscaping of the Water Reclamation Centre. The purpose of the ponds is to ensure that the construction of the Water Reclamation Centre does not impact the volume or water quality of the storm water discharged from the site. The site would be graded to have surface water drain to storm water ponds located in the visual buffer area at the edge of the property. There are other features such as permeable pavement, and roof water retention available to control the volume and quality of
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storm water. These and other stormwater management features will be evaluated during later design stages of the facility. A.6 Operation and Maintenance Strategy
A.6.1 Process Equipment Redundancy Process equipment will be sized per Ministry of Environment (MOE) recommendations, Design Guidelines for Sewage Works, 2008 regarding process equipment redundancy. Specifically:
“Standby or redundant capabilities need to be provided for satisfactory operation of the sewage works during power failures, flooding, peak loads, equipment failure and maintenance shutdowns. Generally, sewage pumping stations and treatment works should be designed so that with the largest flow capacity unit out-of-service the hydraulic capacity of the remaining units can handle the design peak instantaneous flow. The design of a sewage treatment plant should be based on the premise that the failure of any single component should not prevent the sewage works from meeting the required effluent quality and quantity criteria, while operating at design flows. “
A.6.2 Connection to YDSS The interim QHLS Wastewater Servicing Project would provide the local infrastructure in the communities of Queensville, Holland Landing and Sharon. Wastewater would be conveyed to the Water Reclamation Centre as part of the long-term wastewater servicing solution. This project also provides the capability for the 2nd Concession Pumping Station to convey wastewater to the YDSS via the Newmarket Pumping Station as part of the approved interim servicing. Under normal operation the 2nd Concession Pumping Station would convey flow to the Water Reclamation Centre. However, there is benefit in having the operational flexibility for the 2nd Concession Pumping Station to temporarily transfer a portion of the flow to the YDSS. One scenario where flow may be diverted to the YDSS is if for some unanticipated reason the discharge from the Water Reclamation Centre started approaching the facilities annual total phosphorus loading limit. During dry weather flow there is available capacity in the YDSS to accommodate a portion of the wastewater flow from East Gwillimubry. This would temporarily reduce the phosphorus loading to the Water Reclamation Centre and thereby reduce the volume of phosphorus in the effluent. York Region’s operating staff may also decide to temporarily transfer flow to the YDSS to reduce flow to the Water Reclamation Centre for scheduled maintenance activities.
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The close proximity of the YDSS and the Water Reclamation Centre along with the connection provided with interim servicing allows the unique opportunity to have a connection between the two systems and the associated operational flexibility. A.6.3 Compliance and Monitoring The Water Reclamation Centre would be equipped with a combination of sampling and on-line monitoring equipment at critical points within the process. A complete SCADA (supervisory control and data acquisition) system would be incorporated into the design to provide continuous and trended measurement of key operating parameters such as flow and dissolved oxygen. In particular, on-line soluble phosphorus metres would be used to optimize phosphorus removal through metal salt addition. Continuous, on-line flow monitoring would be included at the inlet and discharge structures, and these locations would be equipped with refrigerated automated samplers to measure parameters both for operating and compliance reporting purposes. A.6.4 Staffing The Water Reclamation Centre would be a highly automated state-of-the-art facility with operator control rooms to monitor and control each of the processes. A facility of this size and complexity could be staffed 5.5 days a week, 8 hours a day. The remaining 16 hours a day would have an alarm system such that operators or maintenance would be called in to investigate the alarm and take corrective action. For a facility with highly automated processes, it is assumed less operations staff would be required, but additional instrumentation and controls staffing would be needed to maintain the instruments and control system. Staffing for the Water Reclamation Centre would require administrative, operations, maintenance, and laboratory personnel. It is typical for treatment plants in Ontario to outsource hauling of the treated biosolids; therefore, personnel needed to haul biosolids would not be included in the staffing requirement. It is anticipated that the maintenance staff would have more instrumentation and control technicians than typical plants due to the high level of automation at the Water Reclamation Centre. Maintenance personnel assigned to the facility would work 5 days a week 8 hours a day, but would be available for on call repairs as necessary during off hours. Finally, it is envisioned an on-site lab would process routine analysis for the Water Reclamation Centre. It is assumed laboratory staff would be available 5 days a week, 8 hours a day.
A.7 Implementation Plan
A.7.1 Water Reclamation Centre Construction At the Water Reclamation Centre start-up and during the initial years of operation, the total flow to the Water Reclamation Centre is projected to be less than the year 2031 40 MLD design capacity. This allows the plant to be constructed in phases, such that the initial capacity of the
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plant is better suited to the incoming flows. It also allows for the phase 1 design and operation to be reviewed and the phase 2 design to be optimized based on the performance of phase 1. Capital costs would also be spread over a period of several years. A proposed phasing schedule, with initial plant capacity at 30 MLD is provided in Table A.18. Table A.18: Proposed Water Reclamation Centre Design and Construction Timeline
Stage Water Reclamation Centre Capacity
Timing Flow
Phase 1 Commissioned 30 MLD 2018 4 MLD
Phase 2 Design +10 MLD 2020 – 2021
Phase 2 Construction +10 MLD 2022 – 2024 26 MLD
Phase 2 Commissioning 40 MLD 2024 26 MLD
Phase 2 at Capacity 40 MLD 2031 40 MLD
A.7.2 Reverse Osmosis Post-Conditioning and RO Concentrate Strategy A long-term objective of the UYSS project is to treat the RO concentrate to a level that is suitable for discharge to surface water. This would minimize intra-basin transfer of water (i.e., to Lake Ontario) and allow the RO concentrate to be used to post-condition the RO permeate. While the long-term objective for York Region is to blend the RO concentrate back with the RO permeate, during the initial stage the RO concentrate would be sent to the YDSS for treatment at Duffin Creek WPCP. Therefore RO concentrate re-blending would not be an option for use in RO permeate post conditioning at Water Reclamation Centre start-up. After Water Reclamation Centre start-up, various RO concentrate technologies would be investigated and demonstrated on site prior to implementation at full scale. RO concentrate management has been divided into five phases for implementation:
Initial discharge to the YDSS;
RO concentrate treatment bench-scale investigation;
RO concentrate demonstration testing;
RO concentrate system design; and
Full-scale RO concentrate treatment and reblending with the RO permeate
York Region has confirmed the capacity of the YDSS to accept up to 12 MLD of RO concentrate through to 2031 provided that a minimum 24 hours off-line storage is available under wet weather conditions when the YDSS capacity is constrained.
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A.7.3 Solids Management
The staged approach to management of the RO concentrate offers a unique opportunity to convey solids to the YDSS at the startup of the facility. On-site management of the solids stream is the long term goal for the Water Reclamation Centre. However, at start-up and during the initial stages of operation while the flows are low, on-site solids thickening and digestion of primary and secondary sludge is less economically attractive. The Water Reclamation Centre would be designed to incorporate on-site solids processing in response to economic and regulatory drivers.
Upper York Sewage Solutions Environmental Assessment
Technical Concept Level 2 Report Appendix B BioWin Modeling Results Summary Prepared for: The Regional Municipality of York
Prepared by:
JULY 2014 REF. NO. 050278 (81) YORK REGION NO. 74270
Conestoga-Rovers & Associates 1195 Stellar Drive, Unit 1 Newmarket, Ontario L3Y 7B8
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Table of Contents Page
B.1
Lake Simcoe Water Reclamation Centre BioWin B-1 Simulations
List of Figures Page
Figure B.1 Schematic of the BioWin Configuration B-4
List of Tables
Page
Table B.1 BioWin Steady-State Simulation Conditions B-1 Table B.2 BioWin Influent Design Basis B-2
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Appendix B: BioWin Results Summary B.1: Lake Simcoe Water Reclamation Centre BioWin Simulations BioWin (version 3.1), a commercial software wastewater treatment process simulator, was used to simulate the proposed Lake Simcoe Water Reclamation Centre. A schematic of the BioWin configuration is shown in Figure B.1. This configuration allows for two different liquid-stream treatment processes to be simulated in parallel. For example, “Side A” could represent conventional primary treatment follower by high-rate activated sludge, while “Side B” represents chemically-enhanced primary treatment (CEPT) followed by a 4-stage Bardenpho BNR process. (When a single liquid-stream flow process is simulated, “Side A” and “Side B” are set and perform the same, with each handling half the flow. This is necessary for model convergence). Steady-state simulations were preformed for several sets of operating conditions, as shown in Table B.1. All simulations correspond to the design year in which average annual flow is 40 MLD. Solids handling processes (thickening, fermentation, digestion, and dewatering) were included in order to produce whole-plant mass balances. Chemical precipitation or orthophosphate sing metal salt was included. Caustic and external carbon feed were included. Transformations of colloidal material to particulate associated with the flocculation step of CEPT were added to the model. Nitrate reduction across the primary clarifiers (e.g., by sulfide) was added to the model. Iron sulfide precipitation (under reducing condition) and solubilization (under oxidizing conditions) were added to the model. Table B.1: BioWin Steady-State Simulation Conditions Influent Loads Biological Process
Temperature Portion of Flow to River
Portion of Flow to Reclamation
Average Average 100% 0% Average Summer 100% 0% Average Winter 100% 0% Max Month Average 100% 0% Max Month Summer 100% 0% Max Month Winter 100% 0% Average Average 25% 75% Max Month Average 25% 75% Max Month Summer 25% 75% Max Month Winter 25% 75%
BioWin uses a “COD based” model, which means that multiple state variables representing organic material are expressed in terms of COD, and aggregate parameters such as soluble BOD, particulate BOD, biodegradable VSS, and unbiodegradable VSS are calculated from these state variables. Table B.2 shows the design influent characteristics used in BioWin. For “maximum month” simulations, the influent flow rate was set to 40 MLD, so the relative concentrations for
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“maximum month” and “average” conditions match design load peaking factors from the Water Reclamation Centre Design Basis memo. Because the Lake Simcoe Water Reclamation Centre will need to achieve los effluent nutrient concentrations, it is conservative to use design annual average flows when simulating design maximum month loads. That is, no credit is taken for potential dilution due to higher flows. Table B.2: BioWin Influent Design Basis Parameter Units Default Average Maximum
Month Notes
Inputs COD mg/L - 450 730 To achieve target BOD5 TKN mg/L - 45 54 Design Basis Memo TP-N mg/L - 5 6 Design Basis Memo NO3 –N mg/L - 2 2 Design Basis Memo pH mg/L - 7.5 7.5 Design Basis Memo Alk mg/L - 4.0 4.0 Same as local well water ISS mg/L - 46 104 To achieve target TSS SCa mg/L - 100 100 Design Basis Memo SMg mg/L - 20 20 Design Basis Memo DO mg/L - 0 0 Fbs - 0.160 0.160 0.160 Fac - 0.150 0.150 0.150 Fxsp - 0.750 0.750 0.750 Fus - 0.050 0.050 0.050 Fup - 0.130 0.250 0.351 To achieve target VSS Fna - 0.660 0.650 0.650 Design Basis Memo Fnox - 0.500 0.500 0.500 Fnus - 0.020 0.022 0.022 Design Basis Memo FupN - 0.035 0.035 0.018 To limit part. unbio. N Fpo4 - 0.500 0.500 0.500 FupP - 0.011 0.011 0.0058 To limit part. unbio. P pbCOD/bVSS - 1.6 1.6 1.6 puCOD/uVSS - 1.6 1.6 1.6 Calculated TSS mg/L - 230 415 Design Basis Memo VSS mg/L - 184 311 uVSS mg/L - 71 160 BOD5 mg/L - 190 266 Design Basis Memo sBOD5 mg/L - 94 139
Prefixes in Table B.2 are as follows: “p” = particulate, “s” = soluble, “b” = biodegradable, “u” = unbiodegradable. Input parameters are as presented in Biowin. One biokinetic parameter was changed from its default value. The ordinary heterotrophic organism (OHO) anoxic growth factor was increased from 0.5 to 0.9. This modification is
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consistent with full-scale plant experience, where OHO growth using nitrate or nitrite is not appreciable slower than growth using oxygen. An “anaerobic digester” element was used to simulate a primary sludge fermentation process. In this element only, the methanogen growth rate was set to zero. This is consistent with full-scale plant experience, where methane formation can be prevented by sparging oxygen intermittently. The following tables present mass/flow balances for each set of simulation conditions in Table B.1.
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Figure B.1: Schematic of the BioWin Configuration
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Upper York Sewage Solutions Environmental Assessment
Technical Concept Level 2 Document
Appendix C Geotechnical Report
Prepared for: The Regional Municipality of York
Prepared by:
July 2014 REF. NO. 050278 (81) YORK REGION NO. 74270
Conestoga-Rovers & Associates
1195 Stellar Drive, Unit 1 Newmarket, Ontario L3Y 7B8
REPORT: 050278-060-53.1 PRELIMINARY GEOTECHNICAL INVESTIGATION SHOR LIST OF ALTERNATIVE WATER RECLAMATION CENTRE SITE LOCATIONS EAST GWILLIMBURY, ONTARIO DRAFT February 15, 2013
REGIONAL MUNICIPALITY OF YORK
Preliminary Geotechnical Investigation Short List of Alternative Water Reclamation Centre Site Locations
East Gwillimbury, Ontario DRAFT
Date : February 15, 2013 Our Ref. : 050278-060-53.1
REGIONAL MUNICIPALITY OF YORK
Preliminary Geotechnical Investigation Short List of Alternative Water Reclamation Centre Site Locations
East Gwillimbury, Ontario
O/Ref. : 050278-060-53.1
February 15, 2013
Prepared by :
Shahkar Shahangian, Ph. D., P. Eng.
Approved by :
Renato Paqualoni, P. Eng., PMP
Distribution :
(Copy by e-mail: Tom Casher, P. Eng., PMP [email protected])
cc:
Respect for the environment and the preservation of our natural resources are priorities for Inspec-Sol Inc. With
this in mind, we print our documents double-sided on 50 percent recycled paper.
Contents
1.0 INTRODUCTION ................................................................................................................ 1
2.0 SITE DESCRIPTION .......................................................................................................... 3
2.1 SITE TOPOGRAPHY ..................................................................................................... 3
2.2 PROPOSED DEVELOPMENT ....................................................................................... 4
2.3 GEOLOGICAL SETTINGS ............................................................................................. 5
3.0 SITE INVESTIGATION ...................................................................................................... 7
3.1 SUBSURFACE CONDITIONS ........................................................................................ 8
3.2 SITE WH1 ....................................................................................................................... 9
3.2.1 Fill ............................................................................................................................ 9
3.2.2 Native Soils ............................................................................................................. 9
3.2.3 Groundwater Conditions ........................................................................................ 14
3.3 SITE WH2 ..................................................................................................................... 14
3.3.1 Fill .......................................................................................................................... 15
3.3.2 Native Soils ........................................................................................................... 15
3.3.3 Groundwater Conditions ........................................................................................ 19
3.4 SITE30 .......................................................................................................................... 20
3.4.1 Fill .......................................................................................................................... 20
3.4.2 Silt to Sandy Silt Till ............................................................................................... 20
3.4.3 Granular deposits .................................................................................................. 21
3.4.4 Fine Grained Silty Clay Till .................................................................................... 21
3.4.5 Silty Clay ............................................................................................................... 22
3.4.6 Gravelly Sand ........................................................................................................ 22
3.4.7 Groundwater Conditions ........................................................................................ 22
4.0 INTERPRETATION, DISCUSSION AND RECOMMENDATIONS .................................. 24
4.1 DESCRIPTION OF THE PROJECT .............................................................................. 24
4.2 SUMMARY OF SUBSURFACE CONDITION ............................................................... 24
4.2.1 Site WH1 ............................................................................................................... 24
4.2.2 Site WH1 East ....................................................................................................... 26
4.2.3 Site WH2 ............................................................................................................... 26
4.2.4 Site30 .................................................................................................................... 27
5.0 ENGINEERING DISCUSSION AND ASSESSMENT ...................................................... 28
5.1 GENERAL ....................................................................................................................... 28
5.2 FOUNDATION DESIGN PARAMETERS ................................................................................ 28
5.2.1 Conventional Spread/Strip Footings ...................................................................... 28
5.2.2 Deep Foundations ................................................................................................. 30
6.0 DESIGN CONSIDERATIONS .......................................................................................... 35
6.1 DEPTH OF FROST PENETRATION ..................................................................................... 35
6.2 SEISMIC SITE CLASSIFICATION ........................................................................................ 35
6.3 EXCAVATION .................................................................................................................. 36
6.4 LATERAL EARTH PRESSURE ............................................................................................ 36
6.5 GROUNDWATER CONTROL .............................................................................................. 37
6.6 ENGINEERED FILL ........................................................................................................... 38
7.0 LIMITATIONS OF THE INVESTIGATION ....................................................................... 41
List of Figures Figure 1 – Site location Plan Figure 2 – Borehole Location Plan – Site WH1 West Figure 3 – Borehole Location Plan – Site WH2 Figure 4 – Borehole Location Plan – Site30 and WH1 East List of Tables Table 2.2 WATER RECLAMATION CENTRE Site Layout Facility Sizing - Summary
of Proposed Structures Table 3.2.3 Observed Groundwater Level in the WH1 Installed Monitoring Wells Table 3.3.3 Observed Groundwater Level in the WH2 Installed Monitoring Wells Table 3.4.3 Gradation Analysis of the Granular Deposits Table 3.4.7 Observed Groundwater Level in the Site30 Installed Monitoring Wells Table 5.2.1 Soil Design Parameters and Ground Bearing Capacities for Conventional
Spread/Strip Footings Table 5.2.2.1a Toe Bearing Capacity Factor Table 5.2.2.1b Shaft Bearing Capacity Factor Table 5.2.2.2 Typical Values of Pile Capacity at SLS for Driven Piles Table 6.3 Maximum Slopes for Trench Excavation
List of Appendices
Appendix A Soil Descriptive Terminology
Notes on Borehole and Test Pit Reports
Borehole logs
Appendix B Soil Classification Laboratory Test Results
Preliminary Geotechnical Investigation
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1 Ref. No. : 050278-060-53.1
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1.0 INTRODUCTION
Inspec-Sol, a division of Conestoga Rovers & Associates (CRA) has prepared this
preliminary geotechnical investigation report for three (3) shortlisted alternative sites under
consideration for development as a Water Reclamation Centre, as part of the Upper York
Sewage Solutions (UYSS) Environmental Assessment (EA) Project, underway for The
Regional Municipality of York (York Region).
The three (3) sites are denoted as ‘WH1’, ‘WH2’ and ‘Site30’ (Sites) and are located as
follows (see Figure 1).
Site 30 located on the east side of Leslie Street north of Queensville Sideroad and
south of Holborn Road (i.e., 20913 Leslie Street, East Gwillimbury),
Site WH1 located north of Queensville Sideroad just south of Holborn Road between
2nd Concession Road and Leslie Street (i.e., 20908/20854 Leslie Street, East
Gwillimbury),
Site WH2 located on the east side of 2nd Concession Road just north of Queensville
Sideroad (i.e., 1004 Queensville Sideroad/20709-20733 2nd Concession Road, East
Gwillimbury),
Site 24 located on the west side of 2nd Concession Road, north of Queensville
Sideroad (i.e., 20704 2nd Concession Road, East Gwillimbury).
The geotechnical investigation does not include the fourth short listed site (Site24) because
permission to drill at this location was not provided.
The objective of this preliminary geotechnical investigation was to obtain information on the
subsurface conditions at the Sites by means of a limited number of boreholes, in-situ and
laboratory tests on selected representative soil samples and to provide geotechnical
evaluation to assist in screening the Sites for use as the Water Reclamation Centre. The
data will also be assessed to provide the basis for further geotechnical investigation of the
selected site as related to construction of the Water Reclamation Centre facility. Based on
Inspec-Sol’s interpretation of the data obtained, recommendations are provided on the
geotechnical aspects of the development.
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This report contains the findings of Inspec-Sol’s geotechnical investigation, together with
recommendations and comments. These recommendations and comments are based on
factual information and are intended only for the use of the design engineers.
The results of the geotechnical investigation are presented in two parts. Part 1 contains the
factual data on the soil and groundwater conditions encountered within the boreholes
installed during the present preliminary investigation. In Part 2 of the report, the factual data
is interpreted and geotechnical design comments and recommendations for the
proposed/anticipated structures are presented and different foundation types and ground
improvement techniques are described and the advantage or disadvantage of different
alternatives are discussed.
The anticipated construction conditions are also discussed in this report, but only to the
extent that they may influence design decisions. Construction methods described in this
report must not be considered as specifications or recommendations to the contractors or as
the only suitable methods. The data and their interpretation presented in this report may not
be sufficient to assess all the factors that may have an effect upon the construction.
Prospective contractors, therefore, should evaluate all of the factual information, obtain
additional subsurface data as they might deem necessary and select their construction
methods, sequencing and equipment based on their own experience on similar projects.
On-going liaison with Inspec-Sol during the final design and construction phase of the project
is recommended to ensure that the recommendations in this report are applicable and/or
correctly interpreted and implemented.
The attached ‘Report Limitations’ is an integral part of this report and the recommendations
and opinions in this report are applicable only to the proposed project as described in Section
2.0.
Preliminary Geotechnical Investigation
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3 Ref. No. : 050278-060-53.1
February 15, 2013
2.0 SITE DESCRIPTION
The three (3) shortlisted Sites investigated (WH1, WH2 and 30) are located on the north of
Queensville Sideroad in the Town of East Gwillimbury, Ontario.
Site WH1 extends from 2nd Concession Road to Leslie Street. Site WH2 is located in the
northeast quadrant of Queensville and 2nd Concession Road intersection and Site30 extends
eastward from Leslie Street.
At the time of our field investigation, the Sites were noted to be undeveloped, vacant
agricultural lands.
Figure1 presents the general plan of the area.
2.1 SITE TOPOGRAPHY
Site WH1 covers a total area of about 98 ha. The east and west ends of the Site are
approximately flat. However, the middle of the parcel has a steep slope with a grade
difference of about 35 meters (m) in an approximate north-south direction. The western
segment of the parcel is quite flat with an approximate elevation of 223±m. The eastern
section of the parcel slopes down from southeast towards northwest with a grade of about
4.0 to 5.0 percent.
Site WH2 has a total area of about 114 ha. The western segment of the Site is rather flat and
lies at an Elevation of approximately 224 to 226 m. However, with the exception of the
relatively flat western area, the remainder of the parcel presents a rolling topographical
feature.
The total area of the Site 30 is about 60 ha. General topography of the Site is undulating with
a gentle slope down towards the north, in the direction of the existing ephemeral
watercourse. The Site slopes down from the west and south towards the drainage ditches
heading to depressed areas in the north portions of the area. Based on the ground surface
elevations at the borehole locations, a maximum grade difference in the order of about 19.9
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m was noted at the borehole locations, which is associated with a general gradient of about 4
percent.
Stormwater at the Sites is conveyed overland by natural swales that follow ground
topography but generally drain towards the north.
2.2 PROPOSED DEVELOPMENT
The main components of the proposed facility and their approximate dimensions are
presented in Table 2.2. It is noted that the dimensions presented in the table are preliminary
and subject to modifications.
Table 2.2 - WATER RECLAMATION CENTRE Site Layout Facility Sizing - Summary of
Proposed Structures
Building No. Area
Approximate Height
(m2) (m)
Headworks 1 670 13
HW/Primary Biofilter 1 400 3
Sludge Biofilter 1 400 2
Primary Clarifiers(1) 1 2000 1.5
Flow Balancing Tank(1) 2 800 1.5
Bioreactors (1) 4 1,650 1.5
Secondary Clarifiers(1) 4 615 1
Blower Building 1 450 12
Sand Filtration 1 850 9
MF/UF Building 1 1,350 12
RO Building 1 2,700 15
RO Feed Tanks 2 250 7
UV Building 1 470 9
Emergency Gen. Building 1 540 11
Gravity Thickeners(1) 2 70 3
WAS Thickening Building 1 440 13
Primary Digesters(1) 2 300 12
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Secondary Digester(1) 1 300 15
Biogas Flare 1 20 11
Sludge Holding Tanks (1) 5 710 15
Dewatering Building 1 650 21
Maintenance Building 1 1,900 12
Chemical Feed Building 3 270 11
Administration Building 1 1,900 12
Sludge Truck Loading Building 1 270 12
Post Aeration(1) 1 300 4
Post Conditioning 1 1650 16
(1) Assuming subsurface conditions will allow tank foundations to be up to 6m below grade
2.3 GEOLOGICAL SETTINGS
In addition to a review of the available geological documents related to the shortlisted sites,
the following information sources were consulted to determine the nature of the subsurface
materials of the Site:
1 – “Quaternary Geology of Toronto and Surrounding Area”, Ontario Geological Survey
Preliminary Map 2204, Geological Series, scale 1:100,000, Issued by OMNR-OGS in1980
2 – “Bedrock Geology of Ontario”, Southern Sheet, MNDM and Ontario Geological Survey,
Map No. 2544, scale 1:1,000,000, Issued 1991
3 – Surficial Geology of the Oak Ridges Moraine produced by Geomatics Division, Planning
and Development Services Department of the Regional Municipality of York
4 - Aggregate Resources Inventory of the Town of East Gwillimbury, Regional Municipality of
York, Southern Ontario, prepared by the Ministry of Natural Resources and the Ministry of
Northern Development and Mines, 1988.
Regional geological mapping suggests that the quaternary geology of the Sites and their
general surrounding areas are dominated by the glaciolacustrine deposits of silt, sand and
clay in unconsolidated condition (generally loose to compact relative density) that underlie
the western part of the Sites WH1 and WH2. However, at the eastern part of WH1 and WH2
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as well as at the location of the Site30, glacial till of Halton, Kettleby and Wildfield, underlying
glaciofluvial deposits of sand and silt are anticipated to be encountered.
The overburden deposits in the area are underlain by limestone bedrock of the Middle
Ordovician Lindsay Formation (Simcoe Group). The bedrock surface is expected to be lying
at depths deeper that 30 m below ground surface in the area.
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February 15, 2013
3.0 SITE INVESTIGATION
The fieldwork of the present geotechnical investigation was performed during the period of
June 26 to July 17, 2012. The investigation consisted of advancing a total of sixteen (16)
boreholes, referenced to the related Site and denoted as WH1-1 to WH1-6, WH2-1 to WH2-4
and Site30-1 to Site30-6, at the locations shown on Figures 2 to 4.
The boreholes were advanced using a track mounted power-auger drilling rig, equipped with
hollow-stem continuous-flight augers, under the full-time supervision of experienced
geotechnical personnel from Inspec-Sol. Soil samples were generally taken at 0.76 m depth
intervals to 3.0 m and at 1.5 m depth intervals thereafter, while performing the Standard
Penetration Test (SPT) in accordance with ASTM D1586. This consisted of freely dropping a
63.5 kg (140 lb) hammer a vertical distance of 0.76 m (30 inches) to drive a 51 mm (2
inches) diameter O.D. split-barrel (split-spoon) sampler into the ground. The number of
blows of the hammer required to drive the sampler into the relatively undisturbed ground by a
vertical distance of 0.30 m (12 inches) was recorded as SPT ‘N’ value of the soil which
indicated the consistency or fine-grained soils and relative density of coarse-grained
(granular) deposits. The boreholes were drilled to depths ranging between 12.7 to 21.2 m
below existing ground surface (bgs). However, Borehole WH2-3 was terminated at about 9.6
m of depth due to refusal to augering and soil sampling.
The groundwater level was measured in the boreholes during and upon completion of
drilling. Twelve (12) 50 mm dia. standpipe type monitoring wells were installed in select
boreholes in order to monitor the more-stabilized groundwater level, in a longer period of
time. The groundwater level in the installed monitoring wells was measured on July 29,
2012. The soil conditions, groundwater levels, and the results of in-situ tests are presented
on the corresponding Record of Boreholes attached as Appendix A.
The ground surface elevations at the borehole locations were interpolated from the
topographic drawings for each site. As such, it should be noted that the ground surface
elevations at the borehole locations are approximate and should not be used for construction
purposes.
The field test results were supplemented by laboratory tests. Upon completion of drilling, the
soil samples were transported to Inspec-Sol’s soil laboratory for further examination and
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geotechnical laboratory index testing where they were reviewed by a senior geotechnical
engineer. The laboratory soil index testing program consisted of the measurement of the
natural moisture content of all soil samples, grain size analyses (sieve and hydrometer) of
select soil samples and determination of Atterberg consistency limits on select fine-grained
samples. The results of the index testing are presented in Appendix B.
3.1 SUBSURFACE CONDITIONS
Based on the subsurface conditions encountered in the drilled boreholes, the soil profile in
the area consists generally of the ground surface cover (topsoil and organic rich deposits)
overlying sandy silt to silty sand fill materials, which in turn are underlain by native
glaciofluvial and/or glacial till granular deposits that extended to the termination depth of the
drilled boreholes. It is to be noted that, because of texture similarity between the fill and
native materials and the method of site exploration, the thickness of fill deposit could vary
from what has been noted in the borehole logs.
Topsoil was encountered on the ground surface at all borehole locations and consisted of
organic rich, generally sandy silt to silty sand material with trace clay, occasional gravel,
rootlets and organics.
The subsurface stratigraphic units and groundwater conditions are discussed in the following
sections. Please note that the following summary is to assist the designers of the project with
an understanding of the anticipated soil conditions across the Sites. Additionally, it should be
noted that the soil and groundwater conditions might vary between and beyond the borehole
locations.
It should also be noted that groundwater table in the area will be subject to seasonal
fluctuations and could be somewhat higher in response to major weather events.
Due to the preliminary nature of the geotechnical investigation and the significant distance
between the boreholes, the subsurface condition will be discussed generally for each one of
the three (3) concerned sites in the following sections.
Preliminary Geotechnical Investigation
Short List of Alternative Water Reclamation Centre Site Locations East Gwillimbury, Ontario
9 Ref. No. : 050278-060-53.1
February 15, 2013
3.2 SITE WH1
Boreholes WH1-1 to WH1-4, drilled in the western part of the property and Boreholes WH1-5
and WH1-6, drilled in the eastern part of the property provide information on soil and
groundwater condition at this Site. The ground stratigraphy at each borehole location is
described in the related borehole logs presented in Appendix A.
3.2.1 Fill
The boreholes encountered fill material on the ground surface that extended to depths
ranging from 0.8 m to 2.3 m bgs at the west of the Site and 1.5 m at the location of the
Boreholes WH1-5 and WH1-6, at the east of the Site. The fill material at the borehole
locations is generally a heterogeneous mixture of sandy silt to silt, with trace clay and
occasional gravel. It also contains topsoil, rootlets and organic matters. The fill in the area is
believed to be the on-site reworked material.
The Standard Penetration Test ‘N’ values in the fill deposit were between 8 and 27 and
indicate loose to compact condition of the material.
The moisture content of the samples of fill deposits ranged between 14 to 27 percent which
is associated with moist to wet condition of the material.
3.2.2 Native Soils
Underlying the fill, native deposits of clayey silt to sandy silt were encountered and extended
to the termination depth of the boreholes.
The predominant type of native deposit in the area that extends to the termination depth of
the boreholes is glaciolacustrine silt to sandy silt with trace clay. Layers/lenses of clayey silt
and silty sand with limited thickness were also encountered embedded within the silty
material.
Preliminary Geotechnical Investigation Short List of Alternative Water Reclamation Centre Site Locations East Gwillimbury, Ontario 10 Ref. No. : 050278-060-53.1 February 15, 2013
3.2.2.1 Borehole WH1-1
Silt to Sandy Silt - At the location of Borehole WH1-1 silt to sandy silt deposits were
contacted at about 1.5 m depth bgs and extend to about 15.2 m. These deposits are in
compact to dense condition as indicated by the SPT ‘N’ values of 13 to 42 and the natural
moisture content of the representative samples of the material ranged between 14 and 22
percent. A representative sample of sandy silt deposit contained 30 percent sand, 63
percent silt and 7 percent clay size particles.
Silty Sand Till - At the location of Borehole WH1-1, the sandy silt soils are underlain by a
silty sand till deposit with trace gravel that extends to about 16.7 m bgs (Elev. 206.6 m). A
SPT ‘N’ value of 67 was registered in the soil unit and as such, the material is believed to
have a very dense relative density. However, the high SPT ‘N’ value could be attributed to
the presence of cobble/boulder that could be encountered randomly in glacial deposits.
Silty Clay - Underlying the silty sand, a silty clay deposit was present that extended to the
termination depth of the borehole at 20.43 m (Elev. 203.0 m). The silty clay soil unit is
layered (stratified), contains trace sand and based on the SPT ’N’ values of 0 to 7 obtained in
the deposit, has a very soft to firm consistency. Based on the conducted gradation test, a
sample of the soil unit contained 1 percent sand, 23 percent silt and 76 percent clay size
particles. According to the Atterberg consistency tests carried out on the soil sample, the soil
unit has a liquid limit of 44, plastic limit of 22 and a plasticity index of 22 percent. The natural
moisture content of the soil sample was measured to be 45 percent (slightly greater than the
liquid limit).
3.2.2.2 Borehole WH1-2
Silt to Sandy Silt - At the location of Borehole WH1-2, underlying the fill deposit, the native
deposits generally consist of silt to sandy silt materials with trace clay that were encountered
at about 2.3 m depth bgs (Elev. 220.6 m) and extended to the termination depth of the
borehole. The deposits are in loose to dense condition based on the measured SPT ‘N’
values that ranged between 9 and 41 within the deposits. A deposit of silt with trace clay and
trace to some sand was contacted at about 2.3 m bgs and extended to an approximate depth
of 6.1 m bgs. The SPT ’N’ values measured in the deposit ranged between 10 and 15
indicating a generally loose to compact state of packing of the material.
Preliminary Geotechnical Investigation
Short List of Alternative Water Reclamation Centre Site Locations East Gwillimbury, Ontario
11 Ref. No. : 050278-060-53.1
February 15, 2013
Sandy Silt to Silty Sand - At the location of Borehole WH1-2, sandy silt to silty sand
materials that contain trace to some clay were contacted at about 6.1 m and extended to 9.3
m depth bgs. The SPT penetration numbers ranging between 9 and 16 were registered in the
deposit indicating a loose to compact condition of the material. A sample of the soil unit was
subject of gradation testing and contained 37 percent sand, 55 percent silt and 8 percent clay
size particles. The moisture content of the soil samples of the material ranged between 13 to
20 percent.
Silty Sand - A layer/lens of silty sand, approximately 1.5 m thick, was noted at about 16.8 m
of depth bgs (Elev. 206.1 m), embedded in the finer silty material. The SPT ‘N’ value of 7,
registered in this deposit attests the loose condition of the material. The natural water content
of the soil sample obtained form the silty sand material was 21 percent.
3.2.2.3 Borehole WH1-3
At the location of Borehole WH1-3, the fill deposits are underlain by native silt to sandy silt
that extend to the explored depth of the drilled borehole (20.4 m bgs, Elev. 202.9 m). The
material generally contains trace clay and has no plasticity. However, Sample SS-11 (12.3 m
depth bgs) was noted to contain some clay with plastic behaviour and Sample SS-16B was
noted to be clayey.
The SPT ‘N’ values in the native granular deposits ranged generally in excess of 10 to in
excess of 50 blows for 0.3 m advance of the probe. However, lower values were registered
at about 6.1 m of depth bgs (Elev. 217.2 m) to 9.2 m bgs. The moisture content of the
obtained native soil samples ranged between 14 to 23 percent while the lower values were
related to the dense to very dense material.
A deposit of silty sand has been contacted at 15.2 m depth bgs (Elev. 208.1m) and
extended to about 20.2 m depth. In this deposit a value of zero (0) blow count was recorded
in SS-13 at about 15.5 m depth bgs. Gradation test analyses were conducted on sample SS-
13 and the test results show that the sample contains 60 percent sand, 36 percent silt and 4
percent clay size particles. Considering the other SPT ‘N’ values above and below the noted
depth, the granular sandy nature of the deposit and the negligible amount of clay size
particles, also the elevated groundwater level in the area, the low blow count could be
Preliminary Geotechnical Investigation Short List of Alternative Water Reclamation Centre Site Locations East Gwillimbury, Ontario 12 Ref. No. : 050278-060-53.1 February 15, 2013
attributed to the soil boiling condition due to excess of pore pressure and flow of water into
the borehole during the testing process. The natural water content of the obtained soil
samples from the material ranged between 14 to 16 percent and a value of 34 percent was
also obtained from the clayey silt deposit at the lowermost part of the drilled borehole (SS-
16B).
3.2.2.4 Borehole WH1-4
The native deposits at the location of Borehole WH1-4 consist of silt and sandy silt that
extend to about 9.3 m depth bgs (Elev. 214.4 m) and are underlain by sandy silt till and silty
clay till that extended to the termination depth of the borehole. The silt to sandy silt materials
have a compact relative density according to the SPT ‘N’ values of 12 to 28 blows, obtained
in the material. Two (2) select samples of the deposits were subject to gradation analyses
and contained 5 to 28 percent sand, 68 to 88 percent silt and 4 to 7 percent clay size
particles. The water content of the silty materials in the tested samples ranged between 15 to
20 percent.
The above noted silty deposit in the area are underlain by sandy silt till with trace to some
clay and gravel that extend to about 12.7 m depth bgs (Elev. 211.0 m) at the borehole
location. The deposit has a compact to very dense state of packing as indicated by the SPT
‘N’ values of 15 and 68. The water contents of the two tested samples of the soil unit were 17
and 11 while the lower value corresponded to the very dense material.
Below the depth of 12.7 m (Elev. 211.0 m), silty clay glacial till with trace sand and gravel
was contacted and extended to the termination depth of the borehole. The deposit is grey
and layered (stratified) and according to the obtained SPT ‘N’ values in excess of 30, it has a
hard consistency. Based on the results of the gradation analyses conducted on a select
sample of the material, it contains 1 percent sand, 52 percent silt and 47 percent clay size
particles. The Atterberg Limit tests, carried out on a select sample of the deposit, showed a
liquid limit of 26, a plastic limit of 16 and a plasticity index of 10 for the material while the
natural moisture content of the tested sample was 21 percent.
Preliminary Geotechnical Investigation
Short List of Alternative Water Reclamation Centre Site Locations East Gwillimbury, Ontario
13 Ref. No. : 050278-060-53.1
February 15, 2013
3.2.2.5 Borehole WH1-5
Borehole WH1-5 encountered native silt deposits with trace clay and sand that extended to
about 10.7 m depth bgs (Elev. 251.3 m). Based on the SPT ‘N’ values obtained, these
deposits are dense at the upper parts (SS-3) but turn to very dense at deeper depths. A
gradation analysis carried out on a sample of the material showed that the soil sample
contained 3 percent sand, 79 percent silt and 18 percent clay size particles. The water
content of the extracted samples of the silty material ranged between 17 to 22 percent.
Underlying the silt, an approximately 1.5 m thick layer/lens of clayey silt with trace to some
sand was encountered. The deposit has a slight plasticity. It is in hard condition based on the
SPT ‘N’ value in excess of 100, obtained in the material. The water content of a sample of
the soil unit was 19 percent.
The clayey silt deposit is underlain by a layered/stratified silty sand soil unit that contains
trace to some clay or is clayey and extended to the termination depth of the borehole (12.8
m). As indicated by the SPT ‘N’ value in excess of 100, reported in the material, the silty
sand soil has a very dense relative density. The natural moisture content of two samples of
the material were 5 percent and 16 percent in which the higher moisture content value was
associated with the higher clay content in the deposit.
3.2.2.6 Borehole WH1-6
At the location of Borehole WH1-6, the sandy silt fill extends to the approximate depth of 1.5
m bgs and is underlain by native silt with trace to some sand and trace clay that continues to
about 10.7 m bgs (Elev. 245.3 m). Within the upper part of the deposit (down to about 6 m
bgs) the measured SPT ‘N’ values of 14 to 18 attest a compact condition of the material.
However, the lower part of the soil unit (blow 6 m), the registered SPT ‘N’ numbers ranged
between 40 and 52, indicating a dense to very dense condition of the material.
Gradation analyses (sieve and hydrometer tests) were conducted on a representative
sample of the soil unit and the sample contained 1 percent sand, 89 percent silt and 10
percent clay size particles.
Preliminary Geotechnical Investigation Short List of Alternative Water Reclamation Centre Site Locations East Gwillimbury, Ontario 14 Ref. No. : 050278-060-53.1 February 15, 2013
The silt underlying the above noted silt deposit; clayey silt material was contacted at about
10.7 m depth bgs (Elev. 245.3 m) and extended to the termination depth of the borehole at
15.8 m bgs. The registered SPT ‘N’ values in the clayey silt material ranged between 44 and
54 indicating a hard consistency of the deposit.
The moisture content of the samples obtained from the native silt and clayey silt deposits at
the location of Borehole WH1-6 ranged between 19 and 24.
3.2.3 Groundwater Conditions
No noticeable freestanding groundwater was encountered in the drilled boreholes upon
completion of drilling and the boreholes remained open upon completion. In order to obtain
information on more stabilized groundwater level in the area, 50 mm monitoring wells were
installed in select boreholes. The observed groundwater depth/level during the site
exploration operation is tabulated in Table 3.2.3.
Table 3.2.3 – Observed Groundwater Level in the WH1 Installed Monitoring Wells
Borehole Ground
Elevation MW installed
Groundwater depth/Elev. (m)
July 05, 2012
July 07, 2012
July 09,2012
July 29, 2012
WH1-1 223.4 July 9, 2012 - - - 2.2/221.2
WH1-2 220.9 July 3, 2012 2.9/218.0 3.0/217.9 2.6/218.3 3.0/217.9
WH1-4 223.7 July 4, 2012 - 1.8/221.9 2.3/221.4 2.5/221.2
WH1-5 267.0 July 17, 2012 - - - Dry
WH1-6 256.0 July 17, 2012 - - - 1.6/254.4
3.3 SITE WH2
Four (4) boreholes (WH2-1 to WH2-4) were advanced on the western part of the property of
Site WH2. The ground stratigraphy at each borehole location is described in the
corresponding borehole logs presented in Appendix A.
The following sections present briefly the findings. For additional information on soil
condition, refer to the corresponding borehole logs.
Preliminary Geotechnical Investigation
Short List of Alternative Water Reclamation Centre Site Locations East Gwillimbury, Ontario
15 Ref. No. : 050278-060-53.1
February 15, 2013
3.3.1 Fill
Underlying the ground surface cover, fill soils were encountered at the location of all
boreholes. The fill soils in the area consist of silty sand to sandy silt with trace to some clay
and occasional gravel and extended to depths ranging from 1.0 to 1.5 m bgs at the borehole
locations. Because of its nature and gradation, the fill is believed to be predominantly the on-
site reworked (displaced/disturbed) material.
The Standard Penetration tests SPT ‘N’ numbers within the fill deposits ranged between 7
and 46 blows per 0.3 m penetration, indicating loose to dense condition of the material.
However, in a large majority of the locations, the values, registered between 10 and 30
blows, indicated a compact relative density of the material.
The measured natural moisture content for the fill soils ranged from 11 to 26 percent by
weight, indicating a moist to wet condition.
Cobbles and boulders are expected to be present randomly within the fill deposits.
3.3.2 Native Soils
The predominant type of material at the Site is silty sand to sandy silt glacial till that were
encountered underlying the fill material in all of the boreholes (with the exception of Borehole
WH2-4), and extended generally, to the termination depth of the boreholes. The till deposits
contain trace to some clay and gravel. Gravelly silty sand was also encountered at the
location of WH2-3, underlying the fill deposit, and extended to 2.3 m of depth bgs.
The measured SPT values in the till deposits at the location of the four (4) advanced
boreholes varied from 3 blows to in excess of 50 blows per 0.3 m penetration, indicating a
very loose to very dense condition of the material. The silty sand to sandy silt deposits in the
area are generally not plastic or have a very low plasticity.
It should be noted that due to the nature of their formation, cobbles and boulders are
expected to occur randomly within the glacial till deposits.
Preliminary Geotechnical Investigation Short List of Alternative Water Reclamation Centre Site Locations East Gwillimbury, Ontario 16 Ref. No. : 050278-060-53.1 February 15, 2013
A description of the subsurface condition at each borehole location in more detail is
presented in the following sections.
3.3.2.1 Borehole WH2-1
Sandy Silt to Silty Sand Till - At the location of Borehole WH2-1 native silty sand to sandy
silt till deposits were contacted at about 1.5 m bgs and extended to about 17.0 m bgs. The
deposits contain trace to some clay and trace gravel. The SPT ‘N’ values in the native
deposits ranged between 15 and 73 indicating a compact to very dense relative density of
the material. Gradation analyses (sieve and hydrometer tests) were carried out on a
representative soil sample of the native material (SS-5). The tested sample contained 3
percent gravel, 35 percent sand, 49 percent silt and 13 percent clay size particles. The
gradation analysis test results are presented in Appendix B.
The above noted soil sample was subject to Atterberg Limit tests. The liquid limit (WL) of the
soil sample was 14, its plastic limit (WP) 10 and its plasticity index (PI) was measured to be
4. Therefore, according to the Unified Soil Classification System (USCS) the concerned soil
unit is classified as silty sand to sandy silt. The Plasticity charts related to the tested sample
is presented in Appendix B.
The measured natural moisture content of the native silty sand to sandy silt till soils ranged
generally between 9 to 14 percent. A moisture content value of 2 percent was obtained from
the split spoon SS-10 and was attributed to presence of stone fragments within the soil
sample.
Silt Till - Silt till was contacted at the location of Borehole WH2-1 at about 17.0 m bgs (Elev.
207.8 m) and extended to the termination depth of the borehole. The deposit contains trace
sand, gravel and clay and as indicated by the SPT ‘N’ values of 35 to in excess of 100 blows
per 0.3 m advance of the probe, is in dense to very dense condition. The natural moisture
content of select soil samples of the deposit ranged between 10 to 14 percent.
Preliminary Geotechnical Investigation
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February 15, 2013
3.3.2.2 Borehole WH2-2
Silt Till - Native deposit of silt till with trace clay, sand and gravel was encountered at about
1.5 m depth bgs at the location of Borehole WH2-2 and the fine-grained till material extended
to about 6.1 m depth bgs. The deposit is assessed to have a compact to dense relative
density based on the SPT ‘N’ values that ranged between 19 and 35 within the material. The
natural moisture content of the samples obtained from the soil unit ranged between 15 to 20
percent that were associated with moist to very moist condition of the material.
Silty Sand Till - The silt till deposit is underlain by silty sand till that contains trace to some
gravel and extends to about 9.8 m depth bgs (Elev. 214.4 m). A Gravelly parting/lens was
also noted at about 8.2 m depth bgs. The SPT penetration number (‘N’ value) in the silty
sand till material ranged between 9 and 28 indicating a loose to compact condition of the
deposit. The water content of the obtained samples from the material ranged generally
between 10 and 15 percent. However, a moisture content value of 9 percent was also
reported in Sample SS-8B which is believed to be related to the gravelly nature of the
selected soil sample.
Sandy Silt Till - Underlying the granular silty sand till, finer deposit of sandy silt glacial till
was encountered approximately at 9.8 m depth bgs (Elev. 214.4 m) and extended to about
21.2 m, the termination depth of the borehole. The sandy silt till deposit contains trace clay
and gravel and is assessed to be generally in compact to dense condition as the SPT ‘N’
values of 11 to 34 were registered within the deposit. However, a SPT ‘N’ value of 5 was
recorded at about 18.7 m depth bgs (Elev. 205.5 m) that indicates a loose to very loose
relative density of the material at the noted depth/elevation. The moisture content of the
sandy silt till material ranged between 10 to 15 percent.
3.3.2.3 Borehole WH2-3
Silty Sand Till - Borehole WH2-3 encountered an approximately 1.3 m thick deposit of silty
sand till at about 1.0 m depth bgs. The soil unit is gravelly and contains trace clay. The
penetration numbers of 21 and 31, recorded in the soil unit indicate a compact to dense
relative density of the material. A gradation analysis was carried out on a select sample of
silty sand and the soil sample contained 25 percent gravel, 41 percent sand, 26 percent silt
and 8 percent clay size particles. Based on the Atterberg limit test results, the subject soil
Preliminary Geotechnical Investigation Short List of Alternative Water Reclamation Centre Site Locations East Gwillimbury, Ontario 18 Ref. No. : 050278-060-53.1 February 15, 2013
has a liquid limit of 13, a plastic limit of 9 and a plasticity index of 4. Moisture contents in the
order of 8 to 14 percent were measured within the deposit.
Sandy Silt Till - Underlying the gravelly silty sand till, deposits of sandy silt till were
encountered at about 2.3 m depth bgs (Elev. 223.2 m) and extended to about 9.2 m depth.
The soil unit contains trace clay and gravel and according to the SPT penetration numbers
that ranged between 3 and 38 these deposits have a very loose to dense relative density. A
relatively low SPT ‘N’ value of 3 was registered at about 2.5 m of depth (Elevation 223.0 m)
indicates a very loose state of packing of the deposit at the noted depth/elevation. The water
content of the soil samples obtained from the soil unit ranged closely between 10 and 11
percent.
Clayey Silt - The above noted sandy silt is underlain by a clayey silt deposit that was
contacted at bout 9.1 m depth at the location of Borehole WH2-3 and extended to the
termination depth of the borehole. A SPT penetration number of 68, obtained within the
deposit indicates a hard consistency of the material. The moisture content of a sample of the
soil was 19 percent.
3.3.2.4 Borehole WH2-4
Silt - At the location of Borehole WH2-4, underlying the sandy silt to silty sand fill, a native
deposit of silt was contacted at about 1.1 m depth bgs and extended to the depth of
approximately 4.6 m bgs. The deposit contains trace clay and sand and based on the SPT
penetration numbers that ranged between 15 and 34 at the tested locations, the material has
a compact to dense relative density. Moisture content values of 17 and 19 percent were
measured on the obtained samples of the soil unit.
Silty Sand to Sandy Silt Till - The above noted silt deposits are underlain generally by
glacial silty sand to sandy silt materials that extended to the termination depth of the
borehole (Elev. 209.9 m). Embedded in these granular soils is a sandy gravel material with
an approximate thickness of 0.7 m; that was contacted at about 6.1 m depth bgs. The SPT
penetration numbers ranging between 8 and 44 were registered within the granular soils and
indicate a loose to dense relative density of the material. The relatively low SPT penetration
number was recorded at about 7.2 m of depth bgs (Elev. 217.1 m). Gradation analyses were
conducted on a sample of the deposit and it contained 1 percent gravel, 41 percent sand, 46
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February 15, 2013
percent silt and 12 percent clay size particles. The measured moisture content of the soil
samples obtained from these granular deposits ranged between 10 to 17 percent which were
associated with moist to saturated condition of the material. The gradation and Atterberg
Limit test results are registered in the corresponding borehole log presented in Appendix A
and the representative gradation curve and plasticity chart are provided in Appendix B.
Sandy Gravel - A deposit of sandy gravel with a thickness of about 0.8 m was contacted at
about 6.1 m depth bgs (Elev. 218.1 m) at the location of Borehole WH2-4, embedded in the
silty sand to sandy silt till material. The SPT ‘N’ value of 44, registered in the material,
indicated the dense condition of the deposit. The natural water content of a select sample of
the material was measured and reported to be 17 percent.
Clayey Silt Till - A fine-grained deposit of clayey silt till with trace sand and gravel
embedded in the granular material was contacted at about 12.2 m of depth bgs in Borehole
WH2-4 (Elev. 212.0 m) and extended to 13.7 m bgs (Elev. 209.9 m). The deposit has a
slight plasticity, is grey and contains silt pockets. The Standard Penetration Test ‘N’ value of
10, obtained in the soil unit indicated the stiff consistency of the material and a representative
sample of the deposit had a moisture content of 24 percent.
3.3.3 Groundwater Conditions
No noticeable freestanding groundwater was encountered in the drilled boreholes upon
completion of drilling and the boreholes remained open upon completion. In order to obtain
information on more stabilized groundwater level in the area, 50 mm monitoring wells were
installed in select boreholes. The observed groundwater depth/level during the site
exploration operation is tabulated in Table 3.3.3.
Table 3.3.3 – Observed Groundwater Level in the WH2 Installed Monitoring Wells
Borehole Ground
Elevation MW
Installed
Groundwater depth/Elev. (m)
June 27, 2012
June 28, 2012
June 29,2012
July 03, 2012
July 29, 2012
WH2-1 224.8 Jun 26, 2012 17.8/207.0 16.2/208.6 12.3/212.4 4.9/219.9 1.3/223.5WH2-2 224.2 Jun 28, 2012 - - 4.9/219.3 5.0/219.2 5.7/218.5WH2-4 224.2 Jun 29, 2012 - - - - 3.4/220.8
Preliminary Geotechnical Investigation Short List of Alternative Water Reclamation Centre Site Locations East Gwillimbury, Ontario 20 Ref. No. : 050278-060-53.1 February 15, 2013
3.4 SITE30
Six boreholes (30-1 to 30-6) were drilled to investigate subsurface condition at Site30.
The ground stratigraphy at each borehole location is described in the corresponding borehole
logs presented in Appendix A.
3.4.1 Fill
Underlying the topsoil that covers the area, fill, comprising generally of sandy silt to silt with
trace to some clay and occasional gravel and trace rootlets and organics was contacted at
the location of the drilled boreholes and extended to depths ranging from 1.2 to 2.3 m below
ground level. The fill deposit is in very loose to dense condition as indicated by the SPT ‘N’
values that ranged between 4 and 30 blows.
The natural moisture content of the fill samples obtained from the boreholes ranged between
7 to 23 percent, indicating a moist to wet condition of the deposit.
3.4.2 Silt to Sandy Silt Till
Glacial deposits of silt to sandy silt till with trace to some clay and trace gravel was contacted
underlying the fill at the location of Boreholes 30-1 and 30-2 extending to depths of 3.0 m bgs
and 2.3 m bgs at these borehole locations respectively. The glacial deposit is in compact o
very dense state of packing as attested by the SPT ‘N’ values that ranged between 24 and
70 blows in the soil unit.
Gradation analyses (sieve and hydrometer tests) were conducted on a representative
sample of the deposit which contained 1 percent gravel, 39 percent sand, 47 percent silt and
13 percent clay size particles. The deposits are generally non plastic or have a slight
plasticity.
The moisture content of the samples of the soil unit ranged between 10 to 21 percent
indicating a moist to wet condition.
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February 15, 2013
3.4.3 Granular deposits
The predominant type of material at the site consists of lacustrine silt and sand material that
were contacted underlying the till deposits at the location of Boreholes 30-1 and 30-2 or
underlying the fill soil at the location of the other boreholes and extended, generally, to the
termination depth of the boreholes. These deposits, overridden by glaciers have a compact
to very dense relative density as indicated by the SPT ‘N’ values of 21 to in excess of 50
blows.
The results of gradation analyses, carried out on representative sample of deposits are
presented on Table 3.4.3.
Table 3.4.3 –Gradation Analysis of the Granular Deposits (Site30)
Borehole Sample
Particle size distribution
Gravel
%
Sand
%
Silt
%
Clay
%
30-1 SS-5 0 90 8 2
30-5 SS-5 0 1 85 14
30-6 SS5A 0 10 835 6
3.4.4 Fine Grained Silty Clay Till
At the location of Borehole 30-4, silty clay till was contacted underlying of the fill deposit at
about 2.3 m depth bgs and extended to 9.1 m depth (Elev. 244.6 m). The SPT ‘N’ values in
the glacial deposit ranged form 14 to in excess of 30 blows indicating the stiff to hard
consistency of the material and it appears that soil consistency increases with depth.
Sieve and hydrometer tests were conducted on a representative sample of the deposit and
the soil sample contained 2 percent gravel, 23 percent sand, 55 percent silt and 20 percent
clay size particles. The Atterberg consistency tests carried out on the soil sample (SS-5)
indicated a liquid limit of 20, a plastic limit of 12 and a plasticity index of 8.
The moisture content of the samples of the glacial till deposit ranged between 9 to 15
percent.
Preliminary Geotechnical Investigation Short List of Alternative Water Reclamation Centre Site Locations East Gwillimbury, Ontario 22 Ref. No. : 050278-060-53.1 February 15, 2013
3.4.5 Silty Clay
Silty clay with some sand was encountered at the location of Borehole 30-3, underlying the
above noted granular sandy silt deposits at 2.3 m depth bgs and extends to the termination
depth of the borehole. The Standard Penetration Test numbers increase with depth in the
deposit and ranged between 21 and 79, indicating a very stiff to hard consistency of the
material.
A representative sample of the soil unit contained 18 percent sand, 64 percent silt and 18
percent clay size particles. The Atterberg limit tests carried out on the soil sample indicated
a liquid limit of 19, a plastic limit of 12 and a plasticity index of 7.
The natural moisture content of the samples of the fine-grained silty clay deposit ranged
between 19 to 31 percent, associated with a moist to wet condition.
3.4.6 Gravelly Sand
At the location of Borehole 30-4 the silty clay till is underlain by deposit of gravelly sand. The
coarse grained material was contacted at about 9.1 m depth and extended to about 10.7 m
bgs (Elev. 243.1 m). An SPT ‘N’ value of 43, registered in the soil unit indicates a dense
relative density of the material. The water content of the deposit is measured and reported to
be 13 percent.
3.4.7 Groundwater Conditions
No noticeable freestanding groundwater was encountered in the drilled boreholes upon completion of drilling and the boreholes remained open upon completion. In order to obtain information on more stabilized groundwater level in the area, 50 mm monitoring wells were installed in select boreholes. The observed groundwater depth/level during the site exploration operation is tabulated in Table 3.4.7.
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Table 3.4.7 – Observed Groundwater Level in the Site30 Installed Monitoring Wells
Borehole Ground
Elevation MW
Installed Groundwater depth/Elev. (m)
July 12, 2012 July 13, 2012 July 29, 2012
30-1 265.5 July 10,
2012 4.6 /260.9 4.6/260.9 4.7/260.8
30-4 253.8 July 12,
2012 - 4.4/249.4 4.8/249.0
30-6 271.4 July 13,
2012 - - 4.8/266.6
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4.0 INTERPRETATION, DISCUSSION AND RECOMMENDATIONS
4.1 DESCRIPTION OF THE PROJECT
The proposed Sites for development of Water Reclamation Centre are located in the Town of
East Gwillimbury, Ontario, as shown in Figure 1. The subject parcels have been used for
agricultural purposes in the past and were cultivated to grow corn and other vegetation at the
time of our investigation.
The Water Reclamation Centre will consist of conventional treatment, advanced treatment
and solids management facilities and will comprise the following structures:
In-ground, open top, rectangular or round, concrete tanks, approximately 6 m deep,
with a base slab thickness in the order of 1000 mm and wall thickness of about 800 mm. The
tanks are various sizes. The largest tank is approximately 1,650 square metres,
Large footprint structures with an approximate service load pressure on the footprint
of the base in the order of 100 kPa,
Above ground digester and sludge holding tanks, up to 15 m in height with base
pressures in the order of 200 kPa.
Other tanks that could be steel shells with base pressures up to 100 kPa,
Numerous buildings of varying sizes, generally concrete heavy duty structures with post-
disaster importance, some with basement levels and others on grade, and generally one or
two storeys in height. These vary from administration and maintenance buildings to process
related structures. The buildings vary in footprint with the largest around 2,700 square metres
and the tallest about 15 m high. The footprint of the smaller buildings could be around 300
square metres.
4.2 SUMMARY OF SUBSURFACE CONDITION
4.2.1 Site WH1
Because of its topography and dimension and other site specific conditions, the Site WH1
can be regarded as two distinguished west and east parts that are separated from each other
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by a central wooded area. Four (4) exploratory boreholes (WH1-1 to WH1-4) were drilled at
the western part of the Site WH1 and two (2) additional boreholes (WH1-5 and WH1-6) were
advanced at the east of the Site. Based on the information obtained from the geotechnical investigation, the following general subsurface stratification is provided. For more details of the subsurface conditions, reference should be made to the individual logs of boreholes presented in Appendix A of this report. 4.2.1.1 Site WH1 West
The western part of the Site is underlain by fill deposits that could extend 2.3 m depth bgs.
The fill is overlying fine-grained, lacustrine and glaciofluvial, deposits of clayey silt to sandy
silt (with low plasticity or non plastic), generally in compact or stiff to very stiff condition that
extended to about 15 to 17 m depth (bgs) at the location of Boreholes WH1-1, WH1-2 and
WH1-3 but to about 9 m in Borehole WH1-4.
At the location of Borehole WH1-1, very soft to firm silty clay material was encountered at
about 16.7 m depth bgs (Elev. 206.6 m) and extended to the termination depth of the
borehole at 20.4 m bgs (Elev. 203.0 m).
Borehole WH1-2 encountered a loose deposit of sandy silt with trace clay at about 6.1 m
depth bgs (Elev. 216.8 m) in which a penetration number of 9 was registered. However, in
the standard penetration tests conducted above or below the noted depth/elevation higher
values of 15 and 16 were obtained respectively which are associated with soil compact
condition at the tested locations. A loose deposit of silty sand was also encountered at about
16.8 m depth bgs (Elev. 206.1 m) where a penetration number of 7 has been registered. The
SPT ‘N’ values on the upper and lower tests to the above noted depth/elevation were 41 and
20 respectively that indicate dense and compact relative density of the deposits at the tested
locations respectively.
At the location of Borehole WH1-3, sandy silt material with loose relative density were
encountered at about 6.1 m depth and extended to about 9.2 m bgs and penetration
numbers of 9 and 10 were recorded within the noted interval. A very low SPT ‘N’ value of
zero (0) was recorded at about 15.5 m depth bgs (Elev. 207.8 m). However, higher
penetration numbers of 78 and 61 have been obtained for the upper and lower test locations
relative to the noted depth/elevation. Due to the possibility of soil boiling associated with
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elevated pore pressure and water flow into the borehole during the drilling operation
additional investigation at this depth could be warranted.
Glacial deposits of sandy silt till and silty clay till (in compact to very dense condition) and
silty clay till (with hard consistency) underlie the overlying alluvial deposits at the location of
Borehole WH1-4.
4.2.2 Site WH1 East
At the location of Boreholes WH1-5 and WH1-6 the native deposits consist generally of silt
(in compact to very dense condition) overlying clayey silt (with hard consistency) and very
dense silty sand. The groundwater table in the piezometers installed in the drilled boreholes
was recorded at depths ranging between 2 and 3m below ground level.
4.2.3 Site WH2
The native deposits in Site WH-2 consist generally of granular deposits of silt and sandy silt
to silty sand till, generally with compact to very dense relative density, that extended to the
termination depth of the boreholes.
At the location of Borehole WH2-2 loose deposit of silty sand till was recorded between 7.6
and 9.1 m depth bgs, where a SPT ‘N’ value of 9 was registered. The preceding and
following SPT ‘N’ values were 28 and 23 respectively and could be attributed to the compact
condition of the material at the tested locations. A penetration number of 5 was also obtained
at the location of Borehole WH2-2 at depths between 18.3 and 19.8 m bgs (Elevations 205.9
m and 224.7 m) which is associated with very loose condition of the material. The
penetration numbers in the preceding and following sample to the noted depths were 18 and
11 that indicate compact relative density of the deposits at the tested locations.
At the location of Borehole WH2-3, a low penetration number of 3 was obtained in the sandy
silt till material between 2.3 and 2.9 m depth bgs which indicates very loose condition of the
material. However, the penetration tests carried out above and below the noted depths
provided SPT ‘N’ values of 21 and 12 that indicate compact condition of the material at the
tested locations.
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At the location of Borehole WH2-4 loose sand and silt till deposits were encountered
between 6.9 and 7.5 m depth bgs where a penetration number of 8 was obtained. However,
the preceding and following SPT ‘N’ values were registered as 44 and 12 respectively
indicating a dense and compact condition of the material at the tested locations.
The groundwater level in the installed monitoring wells ranged between 1 m and 6 m depth
(bgs) associated with Elevations 218 to 223 m.
4.2.4 Site30
The fill deposits at the location of the drilled boreholes in Site30 extended to about 1.2 to 2.3
m depth and are underlain generally by granular deposits of silt, sandy silt, silty sand and
sand in compact to very dense condition that extended to the explored depth of investigation.
However, fine-grained silty clay to clayey silt and the same till deposits, having stiff to hard
consistency, were also encountered at the location of Boreholes 30-2, 30-3 and 30-5. The
consistency of the deposits appears to increase rapidly with depth.
The groundwater level in the monitoring wells installed in the area was measured to be at about 4.7 to 4.8 m depth bgs.
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5.0 ENGINEERING DISCUSSION AND ASSESSMENT
5.1 General
Based upon the obtained information from the site investigation and assuming them to be
representative of the subsurface conditions across the Site, the geotechnical bearing
capacity and the type of foundation that could be applicable at each site is discussed in the
following sections. Additional geotechnical investigation is required at the selected Site to
confirm subsurface conditions across the Site in order to develop detailed geotechnical
recommendations for design. Φ
5.2 Foundation Design Parameters
5.2.1 Conventional Spread/Strip Footings
Building or structure foundations can be supported on conventional spread/strip footings or
raft foundations placed on properly prepared native soils. The soil parameters to be used for
design and analysis of the foundation elements are summarized on Table 5.2.1.
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Table 5.2.1 - Soil Design Parameters and Ground Bearing Capacities for Conventional Spread/Strip Footings
Borehole No.
Depth bgs
m
Soil Description
Design Parameters Water Level
Ground Geotechnical
Bearing Capacity
Field SPT 'N'
Values
Friction Angle
Estimated Bulk
Density (γ) bgs SLS ULS
φ degrees
kN/m3 m kPa kPa
WH1-1 2.3 silt to
clayey silt 13 30 19 2.2 200 300
WH1-2 2.3 silt 10 30 19 3 200 300
WH1-3 2.3 silt 10 30 19 NA 200 300
WH1-4 1.2 silt 12 30 19 2.5 200 300
WH1-5 1.5 silt 35 32 20 1.6 400 600
WH1-6 1.5 silt 17 31 20 NA 200 300
WH2-1 1.5 sandy silt to
silty sand 15 31 20 1.3 200 300
WH2-2 1.5 silt till 19 31 20 5.7 200 300
WH2-3 3.0 sandy silt till 12 30 19 NA 200 300
WH2-4 1.0 silt 15 30 19 3.4 200 300
30-1 1.5 sandy silt till 47 35 21 4.7 500 750
30-2 3.0 sandy silt till 74 35 21 NA 500 750
30-3 1.5 sandy silt to
silty clay 21 28 20 NA 200 300
30-4 3.0 silty clay till 21 28 20 4.8 200 300
30-5 1.5 silt 25 29 20 4.8 200 300
30-6 2.3 silt 55 35 21 NA 500 750
NA denotes Not Available
A minimum geotechnical bearing capacity of 200 kPa for a Serviceability Limit State (SLS)
design and 300 kPa for an Ultimate Limit State (ULS) design are available for the design of
spread/strip footings established on competent native stratum. Higher ground bearing
capacities are also available, as noted on Table 5.2.1. Footings must be founded at least 0.3
metres into the undisturbed native stratum for the bearing capacity values provided.
The total settlement of spread/strip footings established on the native strata at this design
bearing pressure is expected to be less than 25 mm and the differential settlements are
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anticipated to be less than 19 mm. A modulus of subgrade reaction (ks) of 25 MPa/m could
be used for the design of a slab-on grade, installed on compact native granular deposit (or on
engineered fill with an appropriate thickness) and a 150 mm thick layer base course,
consisting of OPSS granular ‘A’ material.
A layer/lens of very soft to firm silty clay was encountered at the location of Borehole WH1-1
at a depth of about 16.5 m bgs and extended to the termination depth of the borehole. If this
Site is selected as the preferred alternative for construction of the proposed Water
Reclamation Centre, the extent of the deposit is to be further investigated and, if required,
appropriate soil improvement technique used to improve soil behaviour or deep foundations
are adopted. No similar deposit was encountered in the other boreholes in WH1 or WH2.
Prior to installation of the spread/strip footings or the slab-on-grade, the site should be
stripped of any fill soils, organic/topsoil, loose/soft soils and deleterious materials to expose
an undisturbed subgrade, that will generally consist of compact to very dense granular
material.
Subsequent to stripping and removal of the surficial materials (e.g., topsoil and fill) in the
area of the proposed buildings, any exposed soils which contain excessive organics and
other compressible, weak and deleterious materials should be sub-excavated and removed.
The prepared subgrade then should be compacted with either a smooth-drum vibratory roller
(in granular subgrade) or a sheepfoot roller (in clayey subgrade), and proof rolled using a
loaded triaxle truck in the company of qualified geotechnical personnel. During proof rolling,
spongy, wet or soft/loose spots should be sub-excavated to stable subgrade and replaced
with approved soil, compatible with subgrade conditions, as directed by the geotechnical
engineer. After approval of the exposed subgrade, the grade can be restored to design
grades with compacted engineered fill.
All fill should be placed in 150 to 200mm thick lifts and compacted to at least 98 percent
Standard Proctor Maximum Dry Density (SPMDD). If work is done during wet weather
conditions, partial subexcavation of the exposed subgrade may also be necessary.
5.2.2 Deep Foundations
The following two deep foundation alternatives, cast in place caisson foundations and drive
steel pile foundations, are provided in case significantly higher bearing pressure are required
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than provided above. The design of deep foundations, if required, will require additional
geotechnical investigation.
Consideration should be given to the potential for differential settlement between a building
supported on pile and perimeter sidewalk around the building or other structures that are not
founded on deep foundation.
The ultimate load carrying capacity of a pile will be the sum of its toe bearing capacity and
shaft resistance capacity. The ultimate toe bearing capacity (qtu) and shaft resistance (qsu) for
the piles founded in the undisturbed native soils can be calculated using the relationships1
provided in the following sections.
5.2.2.1 Cast-in-Place Concrete Piles
The ultimate end bearing capacity ‘qtu’ of a cast-in-place concrete pile (caisson) can be
calculated using the following relationship: qtu = Nt x σ’t
where:
qtu = toe ultimate bearing capacity (kPa)
σ’t = vertical effective stress at the pile toe (kPa)
Nt = toe bearing capacity factor, as presented in Table 5.2.2.1a.
Table 5.2.2.1a – Toe Bearing Capacity Factor
Soil Type SPT ‘N’ value range Nt
Compact Sand/Silt 10 to 30 50
Dense Sand/Silt 30 to 50 75
Very Dense Sand/Silt >50 100
1 Canadian Foundation Engineering Manual, 2006, 4th Edition, Canadian Geotechnical Society.
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qsui = β x σ’vi
where:
qsui = ultimate shaft resistance at level i (kPa)
σ’vi = vertical effective stress at elevation i (kPa)
β = shaft bearing capacity factor as presented in Table 5.2.2.1b.
Table 5.2.2.1b – Shaft Bearing Capacity Factor
Soil Type SPT ‘N’ value range β
Compact Sand/Silt 10 to 30 0.35
Dense Sand/Silt 30 to 50 0.45
Very Dense Sand/Silt >50 0.60
The factored ULS bearing resistance can be determined by utilizing a resistance factor (φ) of
0.4 for compression and 0.3 for uplift. The uplift resistance comprises the shaft resistance
only. The SLS bearing resistance can be determined by dividing the ultimate resistances
calculated using the above relationships by safety factors of 3 and 4 for compression and
uplift, respectively to limit the axial movements to 25 mm.
The depth of frost penetration in the area is 1.5 m. It is therefore recommended that the top
1.5 m (frost depth) of the cast-in-place concrete piles be isolated from the surrounding soils.
Subsequently the top 1.5 m length of the pile must not be considered while computing the
axial compression or uplift capacity of the pile. If a pile cap is to be constructed, it should be
totally supported on the piles and must be installed at depths deeper than the depth of frost
penetration so that it is not subject to uplift pressures due to ground heave.
The minimum diameter of the caissons is 760 mm diameter to allow for adequate access for
workman to enter and hand clean the caisson base, prior to placing concrete. The drilled
shaft construction will require the use of a temporary liner so that workmen and inspection
personnel can safely enter the drilled shaft.
5.2.2.2 Driven Steel Pile Foundations
For piles driven to practical refusal, the typical (approximate) values of factored axial, uplift
and lateral capacities at the SLS for steel closed-ended tubular piles and H piles are outlined
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in Table 5.5.2.2. An allowance for corrosion of 0.02 mm/year (i.e. 0.01mm per side) over a
life of 100 years is generally recommended to be been considered for a steel closed-ended
tube piles filled with concrete and the H pile in the calculation of lateral pile capacity.
Table 5.2.2.2 – Typical Values of Pile Capacity at SLS for Driven Piles
Pile Type
Axial
Capacity
(kN)
Lateral
Capacity (kN)
Uplift
Capacity
(kN)
Φ324mmx16mm wall steel tubular
pile, closed ended Grade 350W 650 70 100
HP310x110 steel H pile, Grade 350W 750 90 130
As an approximation, 20 to 30 blows per 25 millimetres of penetration over the last
150 millimetres of driving should be considered as refusal when driven by a
4,500 metre-kilogram (30,000 foot-pound) to 7,000 metre-kilogram (50,000 foot-pound) pile
driving hammer. The allowable axial end bearing capacity of a driven pile will depend on the
type of pile selected, the hammer energy used to advance the pile and the termination
criteria. A specialized piling contractor should review these recommendations and provide
appropriate pile capacities.
Total settlements under the vertical working load equal to SLS capacity, including the elastic
compression of the piles, could be estimated to be less than 15mm. The lateral movements
under the lateral working load equal to the SLS capacity could also be considered to be less
than 15mm. However, any of the above noted values are to be adjusted in the more
advanced studies to the pile/ground condition. As a minimum at least two (2) static pile load
tests are generally recommended to verify the pile capacities for each structure. A pile load
test or pile driving control using the Pile Driving Analyser will be required during the pile
driving operations.
The tubular piles are generally required to be fitted with flange plates as per OPSD 3301.00.
Tube piles should be driven closed ended and fitted with a welded steel circular plate 20mm
thick (OPSD 3302.00 Type 1)
In the feasibility studies, it should be taken into account the possibility that the piles may
drive several metres below the estimated pile tip elevations.
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The base of the pile caps should be provided with a minimum of 1.5 m earth cover or its
thermal equivalent of exterior-grade extruded polystyrene insulation for frost protection.
Noise and vibration during driving, as well as their associated monitoring requirement and
costs, must also be considered for the driven piles alternative.
5.2.2.3 Pile group capacity
For preliminary purposes to establish the pile number and configuration, the group capacity
can be considered equal to the sum of the single pile capacities if the piles are spaced at
least 6 times the pile diameter. Concerning the pile lateral capacity, the single pile capacity
increases with the pile head restraint within the pile cap. For an ideal case of a pile head
fully restraint to rotation (“fixed head”), the single pile capacity is 2 times the capacity of the
“free-head”, or pinned head pile.
Pile group capacity to lateral loads should be examined on a case-by-case basis in an
interactive approach between the Structural Consultant and the Geotechnical Consultant.
The pile group response depends on the pile layout, the structural rigidity of the pile cap and
of the connection between the pile cap and the pile head, and on the configuration of the
acting loads (intensity, direction, eccentricity). A more accurate lateral pile capacity and pile
group design for displacement-sensitive structures is to be conducted on the recognized soil-
structure interaction methods, during the more advanced phases of investigation.
The uplift capacity of a group of piles can be less than the sum of the individual pile
capacities if the distance between the adjacent piles is less than 5 times the pile diameter.
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6.0 DESIGN CONSIDERATIONS
Geotechnical related matters that could have an effect upon the design of the proposed
structures are discussed in the following sections.
6.1 Depth of Frost Penetration
All foundations will need to be founded below frost depth or otherwise protected from frost,
and typical checks for buoyant effects on the in-ground structures will need to be made.
The design frost penetration depth for the general area is 1.5 m. Therefore, a permanent soil
cover of 1.5 m or its thermal equivalent will be required for frost protection of foundations. All
exterior footings and footings beneath unheated areas should have at least 1.5 m of earth
cover or equivalent thickness synthetic insulation (exterior grade rigid extruded polystyrene
insulation) for frost protection.
6.2 Seismic Site Classification
The Ontario Building Code (OBC) requires the assignment of a Seismic Site Class for
calculations of earthquake design forces and the structural design based on a two percent
probability of exceedance in 50 years. According to the OBC, the Seismic Site Class is a
function of soil profile, and is based on the average properties of the subsoil strata to a depth
of 30 m below the ground surface. The OBC provides the following three methods to obtain
the average properties for the top 30 m of the subsoil strata:
Average shear wave velocity;
Average Standard Penetration Test (SPT) values; or
Average undrained shear strength.
Based on the results of the performed geotechnical investigation and based on the criteria
listed in Table 4.1.8.4.A. of the OBC and our knowledge of the regional geology, a Seismic
Site Class ‘D’ can be used for the design of the structures.
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6.3 Excavation
Occupational Health and Safety Act (OHSA) and Regulations for Construction Projects
specifies that where workmen must enter a trench or excavation carried deeper than 1.2 m,
the trench or excavation must be suitably sloped and/or braced in accordance with the OHSA
regulations. Section 226 of the regulations designates four broad classifications of soils to
stipulate appropriate measures for excavation safety, and maximum slopes of excavation as
follows: Table 6.3 - Maximum Slopes for Trench Excavation
The existing soils encountered at the borehole locations below the ground surface have
generally a stiff consistency or compact relative density and can be classified as Type 3 soils
in their undisturbed state above the groundwater level in accordance with the OHSA
regulations. Section 226 of the OHSA Regulations specifies the maximum slope inclination of
1 horizontal to 1 vertical for a Type 3 soil. These deposits are to be considered as Type 4
soil below groundwater level.
6.4 Lateral Earth Pressure
For the relatively shallow excavation depths, installation of a shoring system would probably
not be required. However, if the above recommended excavation side slopes can not be
maintained (due to lack of space, close proximity of other structures, etc.), an engineered
excavation support system must be used. Minimum support system requirements for steep
excavations are stipulated in Sections 234 through 242 of the Act and Regulations. The
engineered shoring system, if required, must be in place prior to commencement of the
installation operations. The shoring system must be designed to be internally (overturning,
and sliding) and externally (slope stability/base heave) stable.
Soil Type Base of Slope Maximum Slope Inclination
1 Within 1.2 m of bottom of trench 1 horizontal to 1 vertical 2 Within 1.2 m of bottom of trench 1 horizontal to 1 vertical 3 From bottom of excavation 1 horizontal to 1 vertical 4 From bottom of excavation 3 horizontal to 1 vertical
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The lateral earth pressure on the buried, underground portion of the structures may be
calculated from the following expression:
p = K(γh+q)
Where
p = lateral earth pressure acting at depth h (kN/m2)
K = earth pressure coefficient
γ = unit weight of soil surrounding the structure (kN/m3)
h = depth to point of interest (m)
q = equivalent value of surcharge on the ground surface (kN/m2)
The above expression does not take into consideration additional groundwater pressure, as it
is assumed that a drainage system will be installed to eliminate the accumulation of
groundwater behind the retaining structure.
In the above equation, the value of K should be taken as Ka for walls that can rotate/deflect
0.004 times the height of the wall; as (Ka + Ko)/2 on walls which are not completely rigid,
while the value of Ko should be used for rigid walls. A value of 0.5 is recommended to be
used for the different soil types at the Sites. However, higher values up to two (2.0) will be
required when rigid structures will be in direct contact with over-consolidated/over-compacted
glacial till deposits at depth.
Excavations must be designed to maintain base stability in accordance with the Canadian
Foundation Engineering Manual 4th Edition. Stability assessment must include the potential
for high hydrostatic pressure from confined water bearing strata. For deep excavations
potentially impacted by hydrostatic pressure consideration should be given to mitigation
measures, the use of cut off walls, or the like. Additional details on the depth of excavations
must be reviewed to assess the potential for base stability.
6.5 Groundwater Control
Seepage is anticipated during excavation operations from surface drainage, perched water in
the fill/reworked granular material, as well as groundwater ingress from fissures and any
permeable features in the native soils encountered within the excavation depth.
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The clayey/silty soils present in the area are, in general, of low permeability, therefore the
volume of water in an excavation limited to these deposits is anticipated to be relatively low
such that, for relatively shallow excavations, temporary pumping from the sump pumps
should be sufficient to control groundwater seepage. However, deeper excavations will
require pre-construction active dewatering and pumping from select sumps, especially where
perched groundwater condition in the fill/reworked native deposits and/or zones of sandy
material are encountered.
To minimize dewatering efforts, the base of the footings should be kept as shallow as
possible, as deeper excavations may require more elaborate (e.g. well points) dewatering
methods.
Excavation within the existing native soils could be kept free of water by pumping from
filtered sumps established around the perimeter or at the base of the excavated area.
However, where seepage is permitted to enter the unsupported excavation, the flow of
groundwater through the faces of excavation (excavation side walls) could trigger instability
of the side walls.
It is to be noted that the dewatering operation might have adverse effect on the adjacent
structures, any underground installations and active wells at the vicinity of the
excavated/dewatered area. The radius of influence of dewatering will depend on the existing
soil permeability, the depth of groundwater lowering and the length of time of dewatering
operation. Where interlocking sheet piling or low permeable shoring system is used to
support the excavation side walls, then it is expected that excavation and dewatering will
have little impact on the adjacent lands or adverse effect on the adjacent structures.
6.6 Engineered Fill
Engineered Fill refers to earth fill (earthworks) designed and constructed with engineering
inspection and testing, so as to be capable of supporting building foundations without
excessive settlement.
Preparation for Engineered Fill and Engineered Fill operations should only be conducted
under full time inspection and testing by the Geotechnical Engineer, in order to ensure
adequate compaction and fill quality. The work consists of, but is not limited to, the following:
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a) Removal of all required fill materials from the ground surface below all areas to be
covered with Engineered Fill,
b) Excavation of Test Holes into the subgrade to investigate the suitability of subsurface
conditions for support of the Engineered Fill and determine if any prior existing fill materials
are present,
c) Proof-rolling of the subgrade (with a heavy rubber-tired equipment such as a loaded
dump truck) below areas to be covered with Engineered Fill, to detect the presence and
extent of unstable ground conditions,
d) Excavation and removal of unstable subgrade materials or other approved stabilization
measures, if required prior to the placement of Engineered Fill,
e) Surveying of ground elevations prior to placing Engineered Fill,
f) Supply, placement, and compaction of approved earth as specified herein, with full time
inspection and testing,
g) Surveying of ground elevations on completion of Engineered Fill placement,
h) Providing and maintaining survey lay out of areas to receive Engineered Fill, and
monitoring of ground elevations throughout the construction of Engineered Fill.
Engineered Fill must not be placed without the approval of the Geotechnical Engineer. Prior
to placing any Engineered Fill, all unsuitable fill materials must be removed, the subgrade
must be investigated for old buried fill or deleterious material, the subgrade must be proof-
rolled and the subgrade elevations must be surveyed.
Prior to the placement of Engineered Fill, the source or borrow areas for the Engineered Fill
must be evaluated for its suitability. Samples of proposed fill material must be obtained by
the Geotechnical Engineer and tested in the geotechnical laboratory for Standard Proctor
Maximum Dry Density, prior to approval of the material for use as Engineered Fill. The
Engineered Fill must consist of clean earth, free of organics and other deleterious material
(building debris such as wood, bricks, metal, and the like).
The Engineered Fill must be placed in maximum loose lift thicknesses of 150 mm. Each lift
of Engineered Fill must be compacted with a heavy roller to at least 98 percent Standard
Proctor Maximum Dry Density, (SPMDD) at the optimum water content plus or minus 2
percent.
Preliminary Geotechnical Investigation Short List of Alternative Water Reclamation Centre Site Locations East Gwillimbury, Ontario 40 Ref. No. : 050278-060-53.1 February 15, 2013
Field density tests must be taken by the Geotechnical Engineer, on each lift of Engineered
Fill. Any Engineered Fill, which is tested and found to not meet the specifications, shall be
either removed or reworked and retested.
A maximum net allowable bearing pressure of up to 150 kPa for SLS design and 225 kPa for
a factored ULS design can be used for foundations placed on engineered fill.
Preliminary Geotechnical Investigation
Short List of Alternative Water Reclamation Centre Site Locations East Gwillimbury, Ontario
41 Ref. No. : 050278-060-53.1
February 15, 2013
7.0 LIMITATIONS OF THE INVESTIGATION
This report is intended solely for Regional Municipality of York (the Client) and is prohibited
for use by others without Inspec-Sol’s prior written consent. This report is considered
Inspec-Sol’s professional work product and shall remain the sole property of Inspec-Sol. Any
unauthorized reuse, redistribution of or reliance on the report shall be at the Client and
recipient’s sole risk, without liability to Inspec-Sol. No portion of this report may be used as a
separate entity; it is to be read in its entirety and shall include all supporting drawings and
appendices.
The recommendations made in this report are in accordance with our present understanding
of the project, the current site use, ground surface elevations and conditions, and are based
on the work scope approved by the Client and described in the report. The services were
performed in a manner consistent with that level of care and skill ordinarily exercised by
members of geotechnical engineering professions currently practicing under similar
conditions in the same locality. No other representations, and no warranties or
representations of any kind, either expressed or implied, are made. Any use which a third
party makes of this report, or any reliance on or decisions to be made based on it, are the
responsibility of such third parties.
All details of design and construction are rarely known at the time of completion of a
geotechnical study. The recommendations and comments made in the study report are
based on our subsurface investigation and resulting understanding of the project, as defined
at the time of the study. We should be retained to review our recommendations when the
drawings and specifications are complete. Without this review, Inspec-Sol will not be liable
for any misunderstanding of our recommendations or their application and adaptation into the
final design.
By issuing this report, Inspec-Sol is the geotechnical engineer of record. It is recommended
that Inspec-Sol be retained during construction of all foundations and during earthwork
operations to confirm the conditions of the subsoil are actually similar to those observed
during our study. The intent of this requirement is to verify that conditions encountered
during construction are consistent with the findings in the report and that inherent knowledge
developed as part of our study is correctly carried forward to the construction phases.
Preliminary Geotechnical Investigation Short List of Alternative Water Reclamation Centre Site Locations East Gwillimbury, Ontario 42 Ref. No. : 050278-060-53.1 February 15, 2013
It is important to emphasize that a soil investigation is, in fact, a random sampling of a site
and the comments included in this report are based on the results obtained at the test
locations only (twelve exploratory boreholes). The subsurface conditions confirmed at the
test locations may vary at other locations. The subsurface conditions can also be
significantly modified by the construction activities on site (ex. excavation, dewatering and
drainage, blasting, pile driving, etc.). These conditions can also be modified by exposure of
soils or bedrock to humidity, dry periods or frost. Soil and groundwater conditions between
and beyond the test locations may differ both horizontally and vertically from those
encountered at the test locations and conditions may become apparent during construction
which could not be detected or anticipated at the time of our investigation. Should any
conditions at the site be encountered which differ from those found at the test locations, we
request that we be notified immediately in order to permit a reassessment of our
recommendations. If changed conditions are identified during construction, no matter how
minor, the recommendations in this report shall be considered invalid until sufficient review
and written assessment of said conditions by Inspec-Sol is completed.
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