F3. Final Air Quality & Odour Net Effects Analysis & Comparative Evaluation Report

Transcription

1 F3. Final Air Quality & Odour Net Effects Analysis & Comparative Evaluation Report

2 Clean Harbors Canada Inc. Lambton Landfill Expansion Environmental Assessment Air Quality & Odour Net Effects Analysis & Prepared By: OCTOBER 2014 REF NO.: )

3 Executive Summary Two expansion alternatives were identified in the approved Terms of Reference ToR) and developed to a preliminary conceptual design level. Alternative 1 Vertical Expansion On-Site would involve the vertical expansion of the existing landfill site i.e., expansion would take place over the previously approved and landfilled areas of the site) see Figure 1). Alternative 2 Shallow Entombment Off-Site would involve the expansion of the site to the south of the existing landfill on adjacent lands already owned by Clean Harbors see Figure 2). Conceptual designs for these two Alternatives have been further refined in the Conceptual Design Report CDR), which was made available during the EA to St. Clair Township and the appropriate review agencies, First Nations, Métis organizations, and the public for their review and comment. This report utilizes the findings of the Air Quality & Odour Existing Conditions Report, the Emission Summary and Dispersion Modelling ESDM) Reports, conditions associated with the currently approved landfill at closure, and the CDR to conduct net effects analyses for the two alternatives proposed for the Clean Harbors Lambton Landfill Expansion, in accordance with the methodology outlined in the approved ToR. This report also details the comparative evaluation of the two proposed Alternative s with respect to Air Quality & Odour based on the results of the net effects analyses. As part of the effects assessment, an ESDM Report was prepared for each alternative to predict the potential maximum point-of-impingement POI) concentrations based on the operating conditions where all Facility air emission sources would be operating simultaneously at their individual maximum rates of production. The Facility was assessed from the ground up to determine all potential sources of air emissions. These sources are documented in detail in the ESDM Reports, and include the Thermal Desorption Unit TDU) and support processes, Facility laboratory exhausts, the incinerator stack and pre-treatment system tanks, the land disposal restrictions LDR) baghouse and fugitive emission sources. The Facility emission sources and locations are shown on Figure 3 and Figure 4 for Alternative 1 and Alternative 2, respectively. Each source was assessed individually to determine potential air contaminant emissions and in each case an appropriate estimation methodology was selected. Methods used include stack testing, mass balance calculations, engineering calculations, and published emission factors. Potential compounds emitted from the Facility include volatile organic compounds VOCs), products of combustion, particulate matter, metals and polychlorinated biphenyls PCBs). A complete listing of all compounds is provided in the ESDM Reports. The potential maximum emission rates for each contaminant emitted from the Facility sources were calculated in accordance with the Ministry of the Environment's publication "Summary of Standards and Guidelines to Support Ontario Regulation 419/05 Air Pollution Local Air Quality" dated April The results of the net effects analyses for Air Quality & Odour for both Alternative s are detailed in the ESDM Reports in Appendix B and C. The ESDM Reports represent the potential maximum worst-case off-site POI concentrations for each Alternative based on the maximum equipment operating capacity and the worst-case on-site truck routes. For the purposes of air quality and odour assessments, point-of-impingement impacts at the property line or beyond are assessed. Impacts at the northern receptors and at the southern receptors have been assessed separately. In addition, potential air emissions from the short-term construction activities, such as fugitive dust, for each Alternative are discussed in Section 2.2. It should be emphasized that Clean Harbors has a Fugitive Dust and Odour Best Management Plan in place to manage and mitigate fugitive dust emissions from the site and this plan will continue regardless of the Alternative chosen. The management plan will i

4 effectively manage and mitigate potential emissions of particulate, and therefore these emissions were not assessed quantitatively. The worst-case net effects are based on the maximum annual projection of 200,000 tonnes per year, and ultimately are linked to the individual maximum processing rates of the waste treatment units. Air emissions from the Facility result in predicted POI concentrations that are below the O. Reg. 419/05 criteria. The AERMOD air dispersion model, used in the ESDM Reports, calculates the predicted maximum off-site POI concentration for each contaminant. The model uses a grid that considers the Facility property boundary and any receptor within 5 kilometres of the property boundary. An additional receptor grid was used at the Aamjiwnaang First Nation lands to identify the predicted maximum off-site POI concentration for each contaminant at any potential receptors within the Aamjiwnaang First Nation boundary. Further details on the receptor grids used in the AERMOD air dispersion modelling are provided in the ESDM Reports. When considering Study Area 1, separate Emission Summary Tables were developed to show predicted impacts at the 10 northern receptors and the 6 southern receptors for each Alternative. The data collected in the annual fenceline monitoring program was used to estimate the maximum impacts from fugitive emissions sources at the site. For Alternative 1, the northern receptors are located in close proximity to the Facility fugitive emission sources, and so it is conservative to assume that 100 percent of the fugitives measured by the fenceline monitors in this area could potentially impact these receptors. The southern receptors are located at a significant distance to the south from these fugitive sources. An area source screening model was used to estimate the additional dispersion due to the increased separation distance from the fugitive emission sources. Based on the results of this screening model, it has been conservatively assumed that approximately 20 percent of the fugitives measured by the fenceline monitors would potentially impact the southern receptors. For Alternative 2, the landfill working face, carbon pits, and leachate pond will be moved to the south, closer to the southern receptors. The northern receptors will continue to be exposed to fugitive emissions from the Facility process sources, including the TDU fugitives. It has been estimated that 60 percent of the fugitive emissions could potentially impact the southern receptors, and 40 percent of the fugitive emissions could potentially impact the northern receptors. Considering POI concentrations, the 10 northern receptors would be most impacted by Alternative 1, and less impacted by Alternative 2 than the southern receptors. However, the northern receptors that are closest to the proposed landfill are already in the vicinity of the existing landfill, and the net change in effects between the existing conditions and Alternative 1 at these receptors is not considered significant. The predicted POI impacts at the northern receptors are tabulated on Table 4A of the ESDM Report prepared to document the impacts of Alternative 1, as provided in Appendix B, and on Table 4A of the ESDM Report prepared to document the impacts of Alternative 2, as provided in Appendix C. Considering POI concentrations, the six southern receptors would be most impacted by Alternative 2. It is important to note that for Alternative 2, the southern receptors are not currently in the vicinity of the existing landfill, and the net change in effects between the existing conditions and Alternative 2 at these receptors is therefore more significant than for the northern receptors. The predicted POI ii

5 impacts at the southern receptors are tabulated on Table 4B of the ESDM Report prepared to document the impacts of Alternative 1, as provided in Appendix B, and on Table 4B of the ESDM Report prepared to document the impacts of Alternative 2, as provided in Appendix C. Considering the net change in potential POI impacts at both the northern and southern receptors, Alternative 1 is the preferred Alternative. Additionally, in order to better understand which Alternative is preferred, potential short-term off-site impacts from construction activities were considered. Potential off-site POI impacts from construction activities would be higher for Alternative 2 as a greater degree of construction is required; earth-moving construction activities and wind erosion of stockpiles are related to potential emissions of particulate. Section 2.2 provides further detail on the construction activities and the discussion for each Alternative. Under normal operations, there are currently no off-site odour concentrations from the Facility. Considering future normal operation, Alternative 2 has a greater potential to produce odour than Alternative 1, due to the leachate management system. Alternative 1 will be an above-ground landfill, and thus leachate will drain from each cell due to gravity) via a sealed drainage system. There will be no opportunity for leachate to pool in the landfill cells. Alternative 2 will make use of a pump system to drain leachate from the landfill cells on an as-needed basis. Managing the odour impacts from Alternative 2 will therefore be more challenging. Alternative 2 also presents a greater risk of an upset condition related to the leachate. Therefore, Alternative 1 is the preferred method when considering odour concentrations. The results of both the net effects analyses and comparative evaluation for Air Quality and Odour will be presented to St. Clair Township, review agencies, First Nations, Métis organizations, and the public for their review and comment prior to conducting the full comparative evaluation of the two Alternatives and identifying a Preferred Alternative. iii

6 Table of Contents Executive Summary 1. Introduction Net Effects Analysis Methodology Evaluation Criteria & Indicators Key Design Considerations & Assumptions Future Baseline Conditions & Assumptions Maximum Impact / Worst-Case Scenario Net Effects Analysis Results Alternative Method 1 Vertical Expansion Alternative Method 2 Southern Expansion Extended Site Life Comparative Evaluation Methodology Comparative Evaluation Results References... 26

7 List of Figures Figure 1. Alternative 1 Figure 2. Alternative 2 Figure 3. Air Emission Source Location Plan Alternative 1 Figure 4. Air Emission Source Location Plan Alternative 2 Figure 5. Total Suspended Particulate Annual Contour Plot - Alternative 1 Figure 6. Total Suspended Particulate Annual Contour Plot - Alternative 1 List of Tables Table 1. Table 2. Table 3. Table 4. Assessment Criteria, Rationale, Indicators and Data Sources Net Effects Analysis Atmospheric Environment - Alternative Method 1 Vertical Expansion On-Site) Alternative Method 2 Shallow Entombment Off-Site) Comparative Evaluation Atmospheric Environment Appendices Appendix A Appendix B Appendix C Glossary of Terms Emission Summary and Dispersion Modelling Report Prepared to Document Alternative Method 1 Evaluation for Environmental Assessment Proposed Lambton Landfill Vertical Expansion Emission Summary and Dispersion Modelling Report Prepared to Document Alternative Method 2 Evaluation for Environmental Assessment - Lambton Landfill Southern Expansion

8 1. Introduction Investigative studies of the following environmental components were carried out as part of the Clean Harbors Lambton Landfill Expansion Environment Assessment EA) for the purpose of generating a more detailed description and understanding of the existing environment that may potentially be affected by the proposed undertaking: Agriculture Archaeological and Cultural Heritage Atmospheric Environment Geology and Hydrogeology Natural Environment Socio-Economic Surface Water Technical These reports were made available during the EA to St. Clair Township and the appropriate review agencies, First Nations, Métis organizations, and the public for their review and comment. Two expansion alternatives were identified in the approved Terms of Reference ToR) and developed to a preliminary conceptual design level. Alternative 1 Vertical Expansion On-Site would involve the vertical expansion of the existing landfill site i.e., expansion would take place over the previously approved and landfilled areas of the site) see Figure 1). Alternative 2 Shallow Entombment Off-Site would involve the expansion of the site to the south of the existing landfill on adjacent lands already owned by Clean Harbors see Figure 2). Conceptual designs for these two Alternative s have been further refined in the Conceptual Design Report CDR), which was made available during the EA to St. Clair Township and the appropriate review agencies, First Nations, Métis organizations, and the public for their review and comment. Following the characterization of the existing environment and further development of the two alternative landfill designs in the CDR, the next step in the EA process is to undertake net effects analyses and a comparative evaluation of the two alternative methods in order to, ultimately, identify a Preferred Alternative. This report utilizes the findings of the Air Quality & Odour Existing Conditions Report, the Emission Summary and Dispersion Modelling ESDM) Reports, conditions associated with the currently approved landfill at closure, and the CDR to conduct net effects analyses for the two alternatives proposed for the Clean Harbors Lambton Landfill Expansion, in accordance with the methodology outlined in the approved ToR. This report also details the comparative evaluation of the two proposed Alternatives with respect to Air Quality & Odour based on the results of the net effects analyses. The results of both the net effects analyses and the comparative evaluation for Air Quality & Odour will be presented to St. Clair Township, review agencies, First Nations, Métis organizations, and the public for their review and comment prior to conducting the full comparative evaluation of the two Alternative s and identifying a Preferred Alternative

9 TRAILERS CEMETERY PETROLIA LINE TELFER ROAD SURFACE WATER POND SURFACE WATER POND SURFACE WATER BUILDING LEGEND GROUND SURFACE CONTOUR PROPERTY BOUNDARY CURRENT WASTE DISPOSAL LIMIT FENCE PROPOSED BASE CONTOURS PROCESS WATER PROPOSED SURFACE WATER DITCH/POND ALIGNMENT SURFACE WATER FLOW DIRECTION CONCEPTUAL LANDFILL EXPANSION FOOTPRINT EXISTING/PROPOSED SCREENING BERM Lambton Landfill Expansion Alternative Method 1 December 2013 Clean Harbors Canada Inc )GN-WA001 DEC 23/2013 Project Figure N E W S

10 S15 EASTING 393, NORTHING 4,747, ,380 sq.m EASTING 394, NORTHING 4,747, WETLAND WOODLOT CULVERT FOR WOODLOT DRAINAGE WOODLOT m LIMIT OF WASTE PERIMETER ACCESS ROAD 10 m BUFFER FROM PROPERTY LINE TELFER ROAD PROPERTY LINE DRAINAGE DITCH SURFACE WATER DISCHARGE DITCH SURFACE WATER TREATMENT PLANT ROKEBY LINE LEGEND GROUND SURFACE CONTOUR SURFACE WATER 197 DRAINAGE DITCH PROPERTY BOUNDARY TREE N FENCE CONCEPTUAL LANDFILL EXPANSION FOOTPRINT CURRENT WASTE W E DISPOSAL LIMIT EXISTING/PROPOSED WOODED AREA SCREENING BERM S Clean Harbors Canada Inc Lambton Landfill Expansion Alternative Method 2 December 2013 Project Figure )GN-WA002 DEC 23/2013

11 2. Net Effects Analysis Methodology With the evaluation criteria, indicators, rationale and data sources confirmed in the approved ToR, the existing conditions characterized and confirmed through the Existing Conditions Report, and the estimated point-of-impingement concentrations POI) for each air contaminant assessed in the ESDM Reports, a net effects analysis was carried out for each of the alternatives consisting of the following activities: 1. Identify potential effects based on indicators) on the environment from each alternative in combination with the currently approved landfill considering maximum predicted waste receipt levels 200,000 tonnes of waste per year for approximately 25 years) for the maximum impact stage or worst-case scenario; Based on design considerations and assumptions included in the CDR Document key design considerations and assumptions applicable to air quality and odour including mitigation measures built into the design) Document future baseline considerations and assumptions applicable to air quality and odour 2. Identify mitigation measures to address potential environmental effects; and Additional mitigation measures beyond those included in the CDR required to further minimize or mitigate identified potential effects) associated with the proposed landfill alternatives 3. Identify net environmental effects taking into account mitigation measures. 2.1 Evaluation Criteria & Indicators The approved ToR set out the assessment criteria and indicators for evaluating the 'alternative methods' i.e., the two alternatives) in the EA. Evaluation criteria were developed for each environmental component listed in the previous section. The criteria and indicators listed in Table 1 were used in the net effects analysis and comparative evaluation for Air Quality & Odour. Table 1. Assessment Criteria, Rationale, Indicators and Data Sources Criteria Rationale Indicators Data Sources AIR QUALITY & ODOUR Air Quality Waste disposal facilities can emit contaminants that degrade air quality. Construction and operation activities at a waste disposal facility can also lead to increased levels of particulates dust) in the air. Predicted off-site point of impingement concentrations g/m 3 ) of indicator compounds. Number of off-site receptors potentially affected residential properties, public facilities, businesses/farms, institutions). Environment Canada Sarnia Airport meteorological data; MOE meteorological data; Site ambient air monitoring, stack testing and continuous emissions monitoring data; Receptors confirmed on recent mapping; - 4 -

12 Table 1. Assessment Criteria, Rationale, Indicators and Data Sources Criteria Rationale Indicators Data Sources Odour Operation activities at a waste disposal facility can result in odours from the site. Predicted off-site odour concentrations g/m 3 and odour units). Number of off-site receptors potentially affected residential properties, public facilities, businesses/farms, institutions). Sarnia Lambton Environmental Association meteorological data and background air quality data; Waste materials and leachate characterization and sampling data; Emissions Summary and Dispersion Modelling ESDM) reports; Landfill design and operation data; Landfill expansion alternatives concepts; Proposed facility characteristics. Environment Canada Sarnia Airport meteorological data; MOE meteorological data; Sarnia Lambton Environmental Association meteorological data and background air quality data; Site odour related data; Site odour complaint history; Waste materials and leachate characterization and sampling data; Receptors confirmed on recent mapping; Odour assessment reports; Landfill expansion alternatives concepts; Proposed facility characteristics. 2.2 Key Design Considerations & Assumptions The CDR provides the proposed layout of the Facility for each Alternative. The existing Facility process sources of air emissions will remain unchanged for each Alternative; therefore, the key design considerations used for evaluating air quality impacts for each Alternative relate to the location of the proposed landfill, the on-site truck routes and the associated construction activities. Under normal operations, there are currently no off-site odour concentrations from the Facility. Considering future normal operation, Alternative 2 has a greater potential to produce odour than Alternative 1, due to the leachate management system. Alternative 1 will be an above-ground landfill, and thus leachate will drain from each cell due to gravity) via a sealed drainage system. AM1 will - 5 -

13 have the hydraulic control layer at the base of all areas where waste is currently placed and at a similar elevation in the three cells that will be excavated below the base of the hydraulic control trench. The hydraulic control layer will allow leachate to seep into the hydraulic control layer and trench on a continuous basis, and hence reduce the potential for leachate ponding to occur. Alternative 2 will make use of a pump system to drain leachate from the landfill cells on an as-needed basis. The main difference between the systems is that for Alternative 1, the leachate will mainly move in unexposed systems, while Alternative 2 will require leachate collection areas small ponded areas) to occur which are then removed by pumping. Managing the odour impacts from Alternative 2 will therefore be more challenging. Alternative 2 also presents a greater risk of an upset condition related to the leachate. Potential fugitive dust emissions from the normal, long-term operation for each Alternative were considered based on the new on-site truck routes that would be used for access to the landfill under each alternative, along with the existing Facility truck routes. Additionally, the location of the leachate ponds is different for each Alternative, and thus the location of the leachate pond vent was modelled for each Alternative to determine off-site POI impacts of indicator compounds. Potential fugitive dust emissions from the short-term construction activities for each Alternative were considered to provide further insight into which Alternative is preferred. As detailed in the CDR, construction required for Alternative 2 is more involved than construction required for Alternative 1 and as such, construction activities for Alternative 2 will have greater potential off-site effects from fugitive dust emissions. It should be emphasized that Clean Harbors has a Fugitive Dust and Odour Best Management Plan in place to manage and mitigate fugitive dust emissions from the site and this plan will continue regardless of the Alternative chosen. The management plan will effectively manage and mitigate potential emissions of particulate, and therefore these emissions were not assessed quantitatively. Construction activities required for each Alternative are described in the following sections. The difference in construction is mainly related to the amount of soil that is required to be removed. In general terms, Alternative 1 requires less soil to be excavated and placed. For Alternative 1, no cover would be placed over the existing landfill until the working landfill cell is complete approximately 3 years for the pre-1986 subcell area). Actual landfilling activity would be the same as existing conditions. There would be some soil movement occurring on a monthly basis. Soil and earth moving activities have the potential to create fugitive dust emissions, which would need to be addressed by the Facility as part of their Fugitive Dust and Odour Best Management Plan. Alternative 1 would be mainly above grade and the average cell excavation depth would be 3-4 m, with a total area of 55.6 m 2. This equates to about 2 million m 3 of soil to be excavated. The cover is to be HDPE with approximately 1 m of soil cover, which totals approximately 550,000 m 3 of cover to be placed. For Alternative 2, all of the southern berm would be constructed initially except for approximately 350 m of the eastern portion. The berm, stormwater pond and ditches, relocation of the northwest pond, south process water pond, and south leachate pond would all be a part of initial construction. Cells would be excavated as required based on the landfilling rate. Soil and earth moving activities have the potential to create fugitive dust emissions, which would need to be addressed by the Facility as part of their Fugitive Dust and Odour Best Management Plan. Alternative 2 would require a complete cell excavation and 5.1 m of cover placement. The proposed area of Alternative 2 is 38.7 ha. The average cell excavation depth would be 11.5 m. This equates to about 4.4 million m 3 of soil to be moved and about 2 million m 3 of cover to be placed. In addition, approximately 368,000 m 3 of this soil will be moved to the perimeter of the site to form berms. Under this Alternative, there would also be potential - 6 -

14 for stockpiles of excavated material. Stockpiles may generate fugitive dust emissions because they are susceptible to wind erosion. The Facility would need to include management and mitigation of the stockpiles in the Fugitive Dust and Odour Best Management Plan. As such, Alternative 2 would require additional mitigation measures with regard to fugitive dust than Alternative Future Baseline Conditions & Assumptions The Existing Conditions Report prepared in the previous stage of the EA process provides a complete inventory of the environmental conditions within the Clean Harbors Lambton Landfill Facility Expansion Study Area at a particular point in time approximately 2012) and reflect the current operation of the existing Clean Harbors Lambton Facility. In order to predict potential environmental effects resulting from each of the proposed alternative methods, the analysis must consider the Study Area's existing conditions at the time of development of the proposed alternatives. These are referred to as the future baseline conditions. At the future baseline year the currently approved Lambton Landfill will be closed; however, all other on-site waste management activities will continue. As per the Closure Plan described in the Lambton Landfill Design and Operational Report March 2010), upon closure of the landfill, the landfill cap will be constructed to its final elevation and contours, covered with topsoil and vegetative cover will be established. Access roads, other earthen works such as berms, drainage ditches and swales, surface water reservoirs, etc.), surface water runoff collection, treatment and discharge, and noise, dust and lighting abatement measures will be maintained as they were during the operational life of the landfill. The Future Baseline Conditions have been considered in the evaluation of the net effects for the Alternative Methods. For each Alternative, the air dispersion modelling in the ESDM Report in Appendix B and C includes the existing Facility sources and the proposed landfill. The existing landfill has not been included in the evaluation of net effects, as the assumption is that it will be closed and capped with no further emissions. 2.4 Maximum Impact / Worst-Case Scenario The ToR states that potential environmental effects will be evaluated considering maximum predicted waste receipt levels. During the period from 2001 to 2010, Clean Harbors landfilled an average of 170,000 tonnes of waste per year. Clean Harbors anticipates that the maximum future waste receipt rate will be comparable to past years and, as such, the net effects analysis considered a conservative maximum predicted waste receipt level of 200,000 tonnes of waste per year for a site life of approximately 25 years. An ESDM Report was prepared for each Alternative to predict the potential maximum point-of-impingement POI) concentrations based on the operating conditions which considered the maximum predicted waste receipt levels and included all Facility air emission sources operating simultaneously at their individual maximum rates of production. The Facility was assessed from the ground up to determine all potential sources of air emissions. These sources are documented in detail in the ESDM Reports, and include the Thermal Desorption Unit TDU) and support processes, Facility laboratory exhausts, the incinerator stack and pre-treatment system tanks, the land disposal restrictions LDR) baghouse, and fugitive emission sources. The Facility emission sources and locations are shown on Figure 3 and Figure 4 for Alternative 1 and Alternative 2, respectively. Each - 7 -

15 source was assessed individually to determine potential air contaminant emissions, and in each case an appropriate estimation methodology was selected. Methods used include stack testing, mass balance calculations, engineering calculations, and published emission factors. Potential compounds emitted from the Facility include volatile organic compounds VOCs), products of combustion, particulate matter, metals, and polychlorinated biphenyls PCBs). A complete listing of all compounds is provided in the ESDM Reports. The potential maximum emission rates for each contaminant emitted from the Facility sources were calculated in accordance with Section 11 of O. Reg. 419/05 Air Pollution Local Air Quality. In addition to considering the maximum predicted waste receipt levels, the net effects analysis was carried out for the maximum impact stage or worst-case scenario for each Alternative. This is a very conservative analysis and results in POI concentrations below the standards in the O. Reg. 419/05 criteria. For Alternative 1, the on-site haul roads will change over time depending on where the working landfill face is located. Potential road configurations for Alternative 1 at various points in the landfill life depending on where the working face would be) were identified. These possible configurations were modelled and the worst-case configuration was identified based on the results. The potential worst-case scenario for road dust was identified to occur when the working landfill face is located to the west of the existing landfill face. The worst-case on-site truck routes for Alternative 1 are presented on Figure 3. This was incorporated into the ESDM Report to evaluate the potential worst-case future off-site concentrations for Alternative 1. For Alternative 2, the on-site haul roads will change over time depending on where the working landfill face is located. The potential worst-case scenario for road dust was identified as being at the beginning of the landfill life when the working landfill face will be located at the point furthest south from the existing Facility longest haul road); this was incorporated into the ESDM Report to assess the potential worst-case future off-site concentrations for Alternative 2. Under this alternative, the leachate ponds and the carbon pits would be relocated south of the existing Facility. These sources emit volatile organic compounds which are indicator compounds assessed in the ESDM Reports. The worst-case on-site truck routes for Alternative 2, along with the locations of the leachate pond and carbon pits are presented on Figure 4. When considering potential worst-case impacts for either Alternative in Study Area 1, separate Emission Summary Tables were developed to show predicted impacts at the 10 northern receptors and the six southern receptors for each Alternative. The data collected in the annual fenceline monitoring program was used to estimate the maximum impacts from fugitive emissions sources at the site. For Alternative 1, the northern receptors are located in close proximity to the Facility fugitive emission sources, and so it is conservative to assume that 100 percent of the fugitives measured by the fenceline monitors in this area could potentially impact these receptors. The southern receptors are located at a significant distance to the south from these fugitive sources. An area source screening model was used to estimate the additional dispersion due to the increased separation distance from the fugitive emission sources. Based on the results of this screening model, it has been conservatively assumed that approximately 20 percent of the fugitives measured by the fenceline monitors would potentially impact the southern receptors. For Alternative 2, the landfill working face, carbon pits, and leachate pond will be moved to the south, closer to the southern receptors. The northern receptors will continue to be exposed to fugitive - 8 -

16 emissions from the Facility process sources, including the TDU fugitives. It has been estimated that 60 percent of the fugitive emissions could potentially impact the southern receptors, and 40 percent of the fugitive emissions could potentially impact the northern receptors

17 )GIS-WA005 May 23, 2014 Legend Clean Harbors Canada Inc. ² m :4,100 UTM Zone 17N, NAD 83 Air Emission Source Location Plan Alternative 1 December 2013 Project Figure 3

18 )GIS-WA006 May 23, 2014 Legend Clean Harbors Canada Inc. ² m :8,200 UTM Zone 17N, NAD 83 Air Emission Source Location Plan Alternative 2 December 2013 Project Figure 4

19 3. Net Effects Analysis Results As previously discussed, the net effects analysis was conducted by documenting potential effects associated with each indicator for the maximum impact stage or worst-case scenario. Mitigation measures were identified to avoid or minimize potential effects and then the net effects were evaluated taking into consideration the application of mitigation measures. The results of this net effects analysis for Alternative 1 and Alternative 2 are described in the following sections. The AERMOD dispersion model was used to predict potential effects on air quality at receptors within 5 km of the Study Area boundary in addition to receptors located within the Aamjiwnaang First Nations lands. Receptors were chosen based on recommendations provided in Section 7.1 of the Air Dispersion Modelling Guideline for Ontario, which is in accordance with s.14 of O. Reg. 419/05. Specifically, a nested receptor grid was used, based on an area that is bounded by a rectangle that encloses every source of contaminants, and spaced out as follows: 20 m spacing within a distance of 200 m from the bounding rectangle 50 m spacing from 200 m to 500 m from the bounding rectangle 100 m spacing from 500 m to 1,000 m from the bounding rectangle 200 m spacing from 1,000 m to 2,000 m from the bounding rectangle 500 m spacing from 2,000 m to 5,000 m from the bounding rectangle In addition to the nested receptor grid, receptors were also placed every 10 m along the property line. No receptors were located within the Lambton Landfill property line. As there is no childcare facility, health care facility, seniors' residence, long-term care facility, or educational facility located at the Facility, same structure contamination was not considered. Receptors within the Aamjiwnaang First Nation lands were located using a uniform discrete receptor grid with 100 m spacing within the community. In addition to the discrete receptor grid, receptors were placed every 10 m along the edges of the Aamjiwnaang First Nation boundary. With the receptors identified in accordance with O. Reg. 419/05, the AERMOD air dispersion model then calculated the predicted maximum off-site POI concentration for each indicator compound. A list of these compounds and associated concentrations is provided in Appendix B and Appendix C. The following sections provide the results of the net effects analysis as it relates to the indicators identified in the approved Terms of Reference for the proposed Lambton Landfill Expansion. Additionally, there are 10 residential receptors that have been considered 'northern receptors' and six residential receptors that have been considered 'southern receptors' based on their location in relation to the Facility. Separate Emission Summary Tables were developed to show predicted impacts at the 10 northern receptors and the six southern receptors for each Alternative. The data collected in the annual fenceline monitoring program was used to estimate the maximum impacts from fugitive emissions sources at the site

20 3.1 Alternative Method 1 Vertical Expansion There are 10 residential receptors that have been considered 'northern receptors' based on their location in relation to the Facility. The 10 northern receptors would be most impacted by Alternative 1. However, the northern receptors that are closest to the proposed landfill are already in the vicinity of the existing landfill, and the net change in effects between Alternative 1 and the existing conditions at these receptors is not considered significant. The predicted POI impacts at the northern receptors are tabulated on Table 4A of the ESDM Report prepared to document the impacts of Alternative 1, as provided in Appendix B. The six residential receptors considered 'southern receptors' based on their location in relation to the Facility would be less impacted by Alternative 1 than the northern receptors. The predicted POI impacts at the southern receptors are tabulated on Table 4B of the ESDM Report prepared to document the impacts of Alternative 1, as provided in Appendix B. Additionally, given that the air dispersion model uses a nested receptor grid, as described in Section 3, to identify the maximum off-site POI concentrations, and the grid used is the same for the assessment of each Alternative, all potential receptors within the grid were included in the evaluation and assessed. The predicted off-site POI concentrations of over 150 indicator compounds assessed for Alternative 1 were compared against criteria listed in the Ministry publication "Summary of Standards and Guidelines to Support Ontario Regulation 419/05 Air Pollution Local Air Quality" dated April The air emissions from the Facility result in predicted POI concentrations of indicator compounds that are all below their respective O. Reg. 419/05 criteria. Figure 5 presents an annual contour plot for total suspended particulate TSP) corresponding to Alternative 1. The figure shows clearly that the northern receptors are most impacted by Alternative 1. Potential fugitive dust emissions from the short-term construction activities for Alternative 1 were considered, to provide further insight into which Alternative is preferred. For Alternative 1, no cover would be placed over the existing landfill until the working landfill cell is complete approximately 3 years for the pre-1986 subcell area). Actual landfilling activity would be the same as existing conditions. There would be some soil movement occurring on a monthly basis. Soil and earth moving activities have the potential to create fugitive dust emissions, which would need to be addressed by the Facility as part of their Fugitive Dust and Odour Best Management Plan. Alternative 1 would be mainly above grade and the average cell excavation depth would be 3-4 m, with a total area of 55.6 m 2. This equates to about 2 million m 3 of soil to be excavated. The cover is to be HDPE with approximately 1 m of soil cover, which totals approximately 550,000 m 3 of cover to be placed. It should be emphasized that Clean Harbors has an existing Fugitive Dust and Odour Best Management in place to manage and mitigate fugitive dust emissions from the site, and this plan will continue regardless of the Alternative chosen. The management plan will effectively manage and mitigate potential emissions of particulate, and therefore these emissions were not assessed quantitatively

21 Under normal operations, there are no off-site odour concentrations from the Facility. As Clean Harbors will continue with their existing practices for managing odour, it is anticipated that there will be no off-site odour concentrations from the Facility under normal operations

22 Pl a Rd Petrolia Line nk 1 ug/m³ /m ³ 1u g/m ³ Brigden Rd ³ g/m 3u Telfer Rd ³ /m ³ ug g/m 2u 1.5 1u ³ g/m ³ ug ug /m Rokeby Line Source: MNR NRVIS, Produced by CRA under licence from Ontario Ministry of Natural Resources, Queen's Printer )GIS-WA003 Legend ² 0 Meters :20,000 UTM Zone 17N, NAD 83 Existing Lambton Facility and On-site Study Areas for Vertical Expansion On-site Alternative Onsite Study Area for Shallow Entombment Off-site Alternative North Residential Receptor South Residential Receptor Total Suspended Particulate Annual Contour Plot Clean Harbors Canada Inc. Total Suspended Particulate Annual Contour Plot Alternative 1 May 2014 Project Figure 5

23 3.2 Alternative Method 2 Southern Expansion There are six residential receptors that have been considered 'southern receptors' based on their location in relation to the Facility. The six southern receptors would be most impacted by Alternative 2. It is important to note that for Alternative 2, the southern receptors are not currently in the vicinity of the existing landfill, and the net change in effects between the existing conditions and Alternative 2 at these receptors is therefore more significant than for the northern receptors. The predicted POI impacts at the southern receptors are tabulated on Table 4B of the ESDM Report prepared to document the impacts Alternative 2, as provided in Appendix C. The 10 residential receptors considered 'northern receptors' based on their location in relation to the Facility would be less impacted by Alternative 2 than the southern receptors. The predicted POI impacts at the northern receptors are tabulated on Table 4A of the ESDM Report prepared to document the impacts of Alternative 2, as provided in Appendix C. Additionally, given that the air dispersion model uses a nested receptor grid, as described in Section 3, to identify the maximum off-site POI concentrations, and the grid used is the same for the assessment of each Alternative, all potential receptors within the grid were included in the evaluation and assessed. The predicted off-site POI concentrations of over 150 indicator compounds assessed for Alternative 2 were compared against criteria listed in the Ministry publication "Summary of Standards and Guidelines to Support Ontario Regulation 419/05 Air Pollution Local Air Quality" dated April The air emissions from the Facility result in predicted POI concentrations of indicator compounds that are all below their respective O. Reg. 419/05 criteria. Figure 6 presents an annual contour plot for total suspended particulate TSP) corresponding to Alternative 2. The figure shows clearly that the southern receptors are most impacted by Alternative 2. Potential fugitive dust emissions from the short-term construction activities for Alternative 2 were considered, to provide further insight into which Alternative is preferred. For Alternative 2, all of the southern berm would be constructed initially except for approximately 350 m of the eastern portion. The berm, stormwater pond and ditches, relocation of the northwest pond, south process water pond, and south leachate pond would all be a part of initial construction. Cells would be excavated as required based on the landfilling rate. Soil and earth moving activities have the potential to create fugitive dust emissions, which would need to be addressed by the Facility as part of their Fugitive Dust and Odour Best Management Plan. Alternative 2 would require a complete cell excavation and 5.1 m of cover placement. The proposed area of Alternative 2 is 38.7 ha. The average cell excavation depth would be 11.5 m. This equates to about 4.4 million m 3 of soil to be moved and about 2 million m 3 of cover to be placed. In addition, approximately 368,000 m 3 of this soil will be moved to the perimeter of the site to form berms. Under this Alternative, there would also be potential for stockpiles of excavated material. Stockpiles may generate fugitive dust emissions because they are susceptible to wind erosion. As such, potential off-site POI impacts from construction activities would be higher for Alternative 2 as a greater degree of construction is required. The Facility would need to include management and mitigation of the stockpiles in the Fugitive Dust and Odour Best Management. It should be emphasized that Clean Harbors has an existing Fugitive Dust and Odour Best Management in place to manage and mitigate fugitive dust emissions from the site, and this plan will

24 continue regardless of the Alternative chosen. The management plan will effectively manage and mitigate potential emissions of particulate, and therefore these emissions were not assessed quantitatively. Under normal operations, there are no off-site odour concentrations from the Facility. As Clean Harbors intends to continue with their existing practices for managing odour, it is anticipated that there will continue to be no off-site odour concentrations from the Facility under normal operations

25 Pl a Rd Petrolia Line nk ³ g/m ³ /m ³ ³ ³ 1 ug/m ³ 1.5 u g /m 2 ug/m 2.5 u g 3 u g/m 4u Telfer Rd Brigden Rd 3.5 ug/m³ 0.5 ug /m ³ /m ³ 1 ug/m³ g 1.5 u Rokeby Line 1u g/m ³ Source: MNR NRVIS, Produced by CRA under licence from Ontario Ministry of Natural Resources, Queen's Printer )GIS-WA004 Legend ² 0 Meters :20,318 UTM Zone 17N, NAD 83 Existing Lambton Facility and On-site Study Areas for Vertical Expansion On-site Alternative Onsite Study Area for Shallow Entombment Off-site Alternative North Residential Receptor South Residential Receptor Total Suspended Particulate Annual Contour Plot Clean Harbors Canada Inc. Total Suspended Particulate Annual Contour Plot Alternative 2 May 2014 Project Figure 6

26 Table 2. Net Effects Analysis Atmospheric Environment - Alternative Method 1 Vertical Expansion On-Site) Environmental Component Atmospheric Environment Criteria Air Emissions Odour Indicators Predicted off-site point of impingement concentrations µg/m 3 ) of indicator compounds. Number of off-site receptors potentially affected residential properties, public facilities, businesses/farms, and institutions). Predicted off-site odour concentrations µg/m 3 and odour units). Number of off-site receptors potentially affected residential properties, public facilities, businesses/ farms, and institutions). Key Design Considerations & Assumptions Existing Facility process sources of air emissions will remain unchanged. Key design considerations used for evaluating air quality impacts relate to the location of the proposed landfill, the on-site truck routes and the associated construction activities. Some soil movement will occur on a monthly basis. AERMOD dispersion model was used to predict potential effects on air quality at receptors within 5 km of the Study Area boundary in addition to receptors located within the Aamjiwnaang First Nations lands. 10 key residential receptors were identified within the vicinity of the proposed landfill. Clean Harbors maintains and will continue to implement the existing Fugitive Dust and Odour Best Management Plan. AERMOD dispersion model was used to predict potential effects on air quality at receptors within 5 km of the Study Area boundary in addition to receptors located within the Aamjiwnaang First Nations lands. 10 key residential receptors were identified within the vicinity of the proposed landfill. Future Baseline Considerations & Assumptions The air dispersion modelling in the ESDM Reports include the existing Facility sources and the proposed landfill. The existing landfill has not been included in the evaluation, as the assumption is that it will be closed and capped with no further emissions. The air dispersion modelling in the ESDM Reports include the existing Facility sources and the proposed landfill. The existing landfill has not been included in the evaluation, as the assumption is that it will be closed and capped with no further emissions. Clean Harbors will continue to implement the existing Fugitive Dust and Odour Best Management Plan. The air dispersion modelling in the ESDM Reports include the existing Facility sources and the proposed landfill. The existing landfill has not been included in the evaluation, as the assumption is that it will be closed and capped with no further emissions. Potential Effects Mitigation Measures Net Effects Predicted off-site POI concentrations of over 150 indicator compounds assessed were compared against MOE criteria and resulted in predicted POI concentrations of indicator compounds that are all below their respective standards. Under Alternative 1, the potential impacts at the 10 northern residential receptors are higher than the potential impacts at these receptors under Alternative 2. Soil and earth moving activities have the potential to create fugitive dust emissions during the short-term construction activities. There are 10 residential receptors located in proximity to the proposed landfill. Under normal operations, there are no off-site odour concentrations from the Facility and therefore, there are no potential effects anticipated. There are 10 residential receptors located in proximity to the proposed landfill. As all POI concentrations of indicator compounds are below their respective standards, no mitigation measures are required. Continue with the implementation of the existing fugitive dust best management program to manage and mitigate potential emissions of particulate. None required. Clean Harbors will continue to implement the Fugitive Dust and Odour Best Management Plan. None required. Although Alternative 1 has slightly higher potential off-site POI concentrations at the northern receptors than Alternative 2, these receptors are already in the vicinity of the existing landfill, and the net change in effects between the existing conditions and Alternative 1 at these receptors is not considered significant. All potential off-site air quality impacts from the Facility comply with the MOE health and risk based Air Quality Standards. Furthermore, fugitive dust emissions will be mitigated through the implementation of the fugitive dust best management program. Although the total number of receptors potentially affected by off-site POI concentrations is higher for Alternative 1 than for Alternative 2, the receptors that are closest to the proposed landfill are already in the vicinity of the existing landfill, and the net change in effects between the existing conditions and Alternative 1 at these receptors is not considered significant. Under normal operations, there are currently no off-site odour impacts from the Facility. As such, no net effects from odour are anticipated. Under normal operations, there are currently no off-site odour impacts from the Facility; however, under an upset scenario in the future, potential off-site odour concentrations would be the same for either Alternative. As such, no net effects from odour are anticipated Rpt-8-Net Effects Report