human health risk assessment and supplementary …€¦ · walker environmental group . ingersoll,...

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WALKER ENVIRONMENTAL GROUP INGERSOLL, ONTARIO

HUMAN HEALTH RISK ASSESSMENT

AND SUPPLEMENTARY HEALTH REVIEW

WORK PLAN

SOUTHWESTERN LANDFILL PROPOSAL ENVIRONMENTAL ASSESSMENT

March, 2017

Prepared For: Darren Fry

[email protected] Walker Environmental Group 160 Carnegie Street Ingersoll, ON N5C 4A8

DRAFT FOR DISCUSSION

HHRA and SHR Work Plan – Southwestern Landfill Proposal Environmental Assessment March, 2017 Intrinsik Corp. – Project # 21325

HUMAN HEALTH RISK ASSESSMENT AND SUPPLEMENTARY HEALTH REVIEW WORK PLAN

SOUTHWESTERN LANDFILL PROPOSAL ENVIRONMENTAL ASSESSMENT

Table of Contents

Page 1.0 INTRODUCTION ............................................................................................................ 1 2.0 PURPOSE & OBJECTIVES ........................................................................................... 3 3.0 ENVIRONMENTAL ASSESSMENT CRITERIA ............................................................. 4 4.0 STUDY DURATIONS ..................................................................................................... 5 5.0 STUDY AREAS .............................................................................................................. 6

5.1 Receptor Locations ...................................................................................................... 7 6.0 INDICATORS/MEASURES ............................................................................................ 8 7.0 ASSUMPTIONS ............................................................................................................. 9

7.1 Facility Characteristics ................................................................................................. 9 7.2 Land Use Forecast ....................................................................................................... 9 7.3 Climate Change ........................................................................................................... 9

8.0 DATA COLLECTION ................................................................................................... 10 8.1 Background Data Collection ....................................................................................... 10 8.2 Field Data Collection .................................................................................................. 10

9.0 DATA ANALYSIS......................................................................................................... 11 9.1 Development of a Conceptual Model.......................................................................... 13

9.1.1 Identification of Chemicals of Potential Concern ................................................. 13 9.1.2 Identification of Sensitive Human Receptors and Locations ................................ 13 9.1.3 Identification of Exposure Pathways .................................................................... 14

9.2 Selection of COPCs for Quantitative Analysis ............................................................ 15 9.2.1 Selection of COPCs in Air ................................................................................... 16 9.2.2 Selection of COPCs in Groundwater and/or Surface Water ................................. 17 9.2.3 Selection of COPCs for Inclusion into the Multi-Media Assessment .................... 18 9.2.4 Developing the Final List of COPCs for Inclusion in the Quantitative HHRA ........ 18

9.3 Quantitative Human Health Risk Assessment Methods .............................................. 19 9.3.1 Exposure Assessment ........................................................................................ 19

Exposure Scenarios ...................................................................................................... 20 9.3.2 Toxicity Assessment ........................................................................................... 21 9.3.3 Risk Characterization .......................................................................................... 22

9.4 Consideration of Chemical Mixtures ........................................................................... 22 9.5 Uncertainty Analysis ................................................................................................... 23

10.0 REPORTING ................................................................................................................ 24 11.0 SUPPLEMENTARY HEALTH ASSESSMENT ............................................................. 25

11.1 Process Overview ................................................................................................... 26 11.2 Scoping .................................................................................................................. 27 11.3 Assessment and Recommendations ....................................................................... 28

12.0 REFERENCES ............................................................................................................. 29 13.0 CONTACT INFORMATION .......................................................................................... 31


HHRA and SHR Work Plan – Southwestern Landfill Proposal Environmental Assessment March, 2017 Intrinsik Corp. – Project # 21325

List of Figures Figure 1-1 Proposed Southwestern Landfill Site Location .................................................... 1 Figure 9-1 Overview of Standard Risk Assessment Framework ......................................... 12 Figure 9-2 Components of the Conceptual Model .............................................................. 13 Figure 9-3 Conceptual Model Example .............................................................................. 15


HHRA and SHR Work Plan – Southwestern Landfill Proposal Environmental Assessment March, 2017 Intrinsik Corp. – Project # 21325 Page 1

HUMAN HEALTH RISK ASSESSMENT AND SUPPLEMENTARY HEALTH REVIEW WORK PLAN

SOUTHWESTERN LANDFILL PROPOSAL ENVIRONMENTAL ASSESSMENT 1.0 INTRODUCTION Walker Environmental Group (Walker) is preparing an Environmental Assessment (EA) for the “provision of future waste landfill capacity at the Carmeuses Lime (Canada) site in Oxford County for solid, non-hazardous waste generated in the Province of Ontario”. Figure 1-1 shows the proposed site location.

Figure 1-1 Proposed Southwestern Landfill Site Location

On March 17, 2016 the Minister of the Environment issued the Notice of Approval to Walker for its Southwestern Landfill Terms of Reference, subject to fifteen further Amendments. Walker published a consolidated version, including these further amendments, under the title “Approved Amended Terms of Reference” (May 10, 2016). Section 8.2 of that document details the approved methodology for evaluating the environmental effects of the proposed landfill, while Appendix B identifies the associated technical studies that are required; this work plan specifically addresses the Human Health Risk Assessment component of the EA. This is one of a series of draft work plans that are being prepared by qualified experts on behalf of Walker for review and discussion among various stakeholders to the EA, each covering a particular area of study. A preliminary version of this work plan was circulated previously during



the development of the Terms of Reference, and this current version has been updated to address comments received at that time from Aboriginal groups, government agencies, and the public. A copy of the earlier comments related to this work plan, along with Walker’s responses and references to where any associated revisions have been incorporated into this updated draft are tabulated in Appendix B. Walker will carefully consider any input received in finalizing the work plans and carrying out the impact assessment studies. Comments on this work plan may be provided to Walker; contact information is supplied at the end of this document.



2.0 PURPOSE & OBJECTIVES The purpose of this study is to complete a Human Health Risk Assessment (HHRA) of the landfill proposed by Walker. The objectives of the study are listed below, in general accordance with the requirements of Section 8.2 of the Approved Amended Terms of Reference:

(a) Describe the environment potentially affected by the proposed undertaking, including both the existing environment as well as the environment that would otherwise be likely to exist in the future without the proposed undertaking.

(b) Carry out an evaluation of the environmental effects of the proposed undertaking, using the environmental assessment criteria described in Appendix A.

(c) Carry out an evaluation of any additional impact management actions that may be necessary to prevent, change or mitigate any (negative) environmental effects.

(d) Prepare a description and evaluation of the environmental advantages and disadvantages of the proposed undertaking, based on the net environmental effects that will result following mitigation.

(e) Prepare monitoring, contingency and impact management plans to remedy the environmental effects of the proposed undertaking.

Walker will prepare and provide a set of initial design and operating assumptions for the landfill prior to the initiation of the assessment, and following its review of alternatives1. Walker will also prepare and provide a forecast of future land use assumptions for the purposes of projecting future environmental baseline conditions.

1 Note that this work plan may be amended or adjusted prior to the initiation of the assessment in order to

properly accommodate the preferred alternatives that arise from that review.



3.0 ENVIRONMENTAL ASSESSMENT CRITERIA Walker launched the EA for the Southwestern Landfill proposal in March 2012. Since launching the EA, Walker has been collecting input from the public on characteristics of the local environment that should be evaluated through the EA process. Walker developed the environmental assessment criteria to be used for this EA using input received from the public, previous experience with the EA process and guidelines published by the Ministry of the Environment. Appendix A contains a complete list and detailed descriptions of the approved environmental assessment criteria that are proposed to be used in this EA. From that list, the following are the primary environmental assessment criteria that are to be addressed in the Human Health Risk Assessment, along with examples of related issues heard by Walker during public consultation about the proposal:

Environmental Criteria Issue(s) Raised through Public Consultation

Effects due to exposure to air emissions

Health effects arising from exposure to air emissions from facility and vehicles using haul route. Health effects of potential impacts on home garden or agricultural food chain from facility emissions.

Effects due to fine particulate exposure

Health effects arising from exposure to particulate emissions from facility and vehicles using haul route. Health effects due to contact with soils impacted by deposited emissions from the facility. Health effects of potential impacts on home garden or agricultural food chain from facility emissions.

Effects due to contact with contaminated groundwater or surface water

Health effects due to contact with groundwater or surface water impacted by discharges from the facility

Furthermore, this study is also designed to provide key input/data to other environmental criteria that will be addressed through studies conducted by other experts. These criteria include:

Environmental Criteria Issue(s) Raised through Public Consultation Primary Expert

Disruption to use and enjoyment of residential properties

Health implications of emissions (particulate and vapour) from the Site Social/Cultural

Disruption to use and enjoyment of public facilities and institutions

Health implications of emissions (particulate and vapour) from the Site Social/Cultural

Disruption of Farm Use Health implications of emissions (particulate and vapour) from the Site impacting agricultural foods Agricultural

Property value impacts Health implications of emissions (particulate and vapour) from the Site impacting property values Economics

It should be noted that the above list is not a complete list of the criteria and experts that may use the findings of the Human Health Risk Assessment. Intrinsik will make our findings available to all experts for use in evaluating any environmental criteria the individual experts determine as necessary.



4.0 STUDY DURATIONS For each of the primary criteria to be addressed in this study, two durations (or time frames) will be considered in which potential environmental effects can occur: Operational Period The time during which the waste disposal facility is constructed,

filled with waste, and capped. These activities are combined since they occur progressively (i.e., overlap) on a cell-by-cell basis, and they have a similar range of potential effects (e.g., there is heavy equipment active on the site).

Post-Closure Period The time after the site is closed to waste receipt. Activities are normally limited to operation of control systems, routine property maintenance and monitoring, and thus have a more limited range of potential effects.

Table A1 appended to this work plan identifies the study duration associated with each of the criteria. For this Human Health Risk Assessment, all three evaluated criteria (i.e., “Effects due to exposure to air emissions”, Effects due to fine particulate exposure”, and “Effects due to contact with contaminated groundwater or surface water”) will consider both operational and post-closure periods.



5.0 STUDY AREAS Table A1 in Appendix A identified three general study areas: On-Site and in the Site Vicinity

On-site includes the waste disposal facility plus the associated buffer zones. Site vicinity is the area immediately adjacent to the waste disposal facility property that is directly affected by the on-site activities. Its size will be variable and flexible in order to encompass the actual extent of the effects, but could consist of neighbouring properties and/or communities as needs be.

Along the Haul Routes The primary route along which waste disposal facility truck traffic moves between a major provincial highway and the waste disposal facility site entrance, plus the properties directly adjacent to these roads.

Wider Area

The wider area, generally beyond the immediate site vicinity. Depending on the particular criterion this may include neighbourhoods, local municipalities, Oxford County, or the Province. This study area can also be used for some of the general or indirect effects of a landfill that are not resulting from specific physical activities on the site.

Table A1 indicates the relevant study areas that will be examined for each of the criteria. These study areas are not intended to be fixed. Flexibility is available to expand or contract study areas, depending on the study findings. For the purposes of this Human Health Risk Assessment, the initial estimate of the study areas based on our current understanding of the proposed site, and other landfills, is as follows: On-Site and in the Site Vicinity

For the purposes of the evaluation of health impacts of air emissions from the Site, the on-site and in the site vicinity area typically extends to approximately 5 kilometres from the proposed landfill. This is based on the maximum extent of air quality effects that can be anticipated. However, the modeling area will predict the full extent of air quality effects from the landfill operations even if they were to extend beyond 5 km, and the study area would then be adjusted accordingly. As contaminants associated with the Site can potentially enter the groundwater or surface water and impact off-site groundwater or surface water, the Site Vicinity will also include the local area where surface water discharge from the Site is currently permitted (i.e., the Thames River) and where the groundwater may potentially be drawn down to below original water levels, due to the existing and proposed activities at the Site (i.e., quarrying).



Along the Haul Routes

The along the haul route area for this will be limited to 500 metres on both sides of the proposed haul routes and dominant emergency detour routes as provided by the traffic consultant, and will apply only to the criteria related to vehicle emissions and retrained roadway dust. This is based on the maximum extent of air quality effects that can be anticipated from typical roadway sources of emissions. However, the modeling area will predict the full extent of air quality effects from the haul route even if they were to extend beyond 500 m area around the haul route, the study area would then be adjusted accordingly.

The proposed study areas for this assessment are a culmination of all of the study areas applied within the main EA studies (e.g., air quality, groundwater and surface water, traffic) that are relied upon for the HHRA. 5.1 Receptor Locations For the purposes of this EA, a number of receptor locations will be identified to assist with the consideration of the effects that may result from the project. Some of these receptor locations will be common with other disciplines to ensure that the assessment considers multiple and/or cumulative effects. The number and locations of these common receptors will be determined in a collaborative fashion with other disciplines, (i.e., air quality, noise/vibration, social/cultural, economics/financial, agriculture, traffic and visual/landscape disciplines). These common receptor locations may include those locations that represent the following:

• Residences or neighbourhoods nearest the proposed landfill (nearest residential locations to the north, south, east and west of the site);

• Residences or neighbourhoods along the haul route;

• Businesses or commercial/industrial areas, including farms or agricultural areas;

• Community or institutional facilities nearest the proposed landfill (e.g., schools, community centres, hospitals, cemeteries);

• Areas or places with a potential view of the proposed landfill;

• Recreational areas nearest the proposed landfill (e.g., parks, conservation areas, trails);

• Areas or places used by Indigenous peoples for traditional purposes;

• Areas or places of ecological importance;

• Areas or places identified for future development (e.g., vacant properties)



6.0 INDICATORS/MEASURES Indicators identify how the potential environmental effects will be measured for each criterion. Following are the indicators that are proposed for each of the primary EA criteria to be addressed in this assessment:

EA Criteria Proposed Indicators/Measures

Effects due to exposure to air emissions Comparisons of predicted air concentrations to acute, sub-chronic, and chronic inhalation health-based benchmarks.

Effects due to fine particulate exposure Comparisons of predicted air concentrations to acute, sub-chronic, and chronic inhalation health-based benchmarks.

Effects due to contact with contaminated groundwater or surface water

Comparisons of predicted groundwater concentrations to acute, sub-chronic, and chronic oral health-based benchmarks.

A detailed discussion of the various regulatory benchmarks used to evaluate air and groundwater concentrations of each of the Chemicals of Potential Concern (COPCs) is provided in Section 8 of this document. A COPC is a contaminant identified as of interest for evaluation as part of the risk assessment. In the case of the current assessment, these include the criteria air contaminants, as well as those 23 compounds of interest in landfill gas, as outlined in the MOE’s Guide to Assess Air Impacts from Landfills (MOE, 1992). Refer to the Air Quality Assessment Work Plan for further information on initial air quality COPC selection. Selection of COPCs for the groundwater assessment will be based on the outcome of investigations by the Groundwater/Surface Water Assessment conducted by Golder. Measured and modeled concentrations will be evaluated versus relevant provincial and federal groundwater standards.



7.0 ASSUMPTIONS 7.1 Facility Characteristics Walker has provided an initial set of working assumptions regarding the design and operations of the proposed landfill (Facility Characteristics Report; November, 2016). The following key assumptions are drawn from that report for the purposes of this study.

• This study is reliant on data from the other main EA studies, including the air quality study, groundwater and surface water study, and the traffic study; therefore, the HHRA is subject to the same assumptions regarding facility characteristics that are used within each of these studies.

7.2 Land Use Forecast In order to address cumulative effects, in accordance with the methodology set out in Section 8.2 of the Approved Amended Terms of Reference, this study will compare the potential effects of the proposed landfill at its different stages of development to the forecast baseline conditions at that same period of time (i.e., the “do nothing” alternative). In order to guide the forecasting of future baseline conditions, Walker has provided a set of working assumptions regarding future land uses (including community growth, other industrial activities such as quarrying, etc.) at the site, in the surrounding area and in the broader community.

• This study is reliant on data from the other main EA studies, including the air quality study, groundwater and surface water study, and the traffic study; therefore, the HHRA is subject to the same assumptions regarding facility characteristics that are used within each of these studies.

7.3 Climate Change Minister’s amendment #12 to the Approved Amended Terms of Reference required that climate change should be considered in this environmental assessment. The following table summarizes the mean climate change (temperature and precipitation) assumptions to be considered during this study, where relevant.

Temperature (oC) Precipitation (mm) Annual Summer Winter Annual Summer Winter 2011-2040 +2.3 +2.0 +2.2 +52.0 -2.7 +28.3 2041-2070 +3.9 +3.2 +4.5 +87.0 -2.5 +34.9

2071-2100+ +4.8 +4.1 +5.5 +89.0 -4.4 +46.8 Source: McDermid, J., S. Fera and A. Hogg. 2015. Climate change projections for Ontario: An updated synthesis

for policymakers and planners. Ontario Ministry of Natural Resources and Forestry, Science and Research Branch, Peterborough, Ontario. Climate Change Research Report CCRR-44.



8.0 DATA COLLECTION 8.1 Background Data Collection All background and predicted future air concentrations for the relevant COPCs will be provided by the Air Quality Study. The Air Quality Study will also provide deposition rates for relevant COPCs which will be used by the HHRA Study Team to predict other exposure media concentrations (e.g., surficial soil, home garden soils, home garden produce, agricultural food chain, etc.). 8.2 Field Data Collection Groundwater and surface water concentrations for the relevant COPCs will be provided by the Groundwater/Surface Water Assessment Study.



9.0 DATA ANALYSIS In general, a Human Health Risk Assessment (HHRA) is a scientific study that evaluates the potential for the occurrence of adverse health effects from exposures of people (receptors) to Chemical of Potential Concern (COPC) present in surrounding environmental media (e.g., air, soil, sediment, surface water, groundwater, food and biota, etc.), under existing or predicted exposure conditions. HHRA procedures are based on the fundamental dose-response principle of toxicology. The response of an individual to a chemical exposure increases in proportion to the chemical concentration in critical target tissues where adverse effects may occur. The concentrations of chemicals in the target tissues (the dose) are determined by the degree of exposure, which is proportional to the chemical concentrations in the environment where the receptor resides, works or visits. All chemicals (anthropogenic and natural) have the potential to cause environmental effects in people and the ecosystem. However, it is the chemical concentration, the route of exposure, and the inherent toxicity of the chemical that determines the level of environmental effect and potential for unacceptable risk to the exposed receptor. As illustrated in the diagram to the right, if all three components are present (i.e., where the three circles intersect), the possibility of adverse risk exists. The prediction of an individual’s exposure to specific chemicals in the environment and the potential risks resulting from such exposures can be determined through the completion of a quantitative HHRA. The proposed HHRA will follow the standard HHRA framework (see Figure 9-1) that is composed of the following steps:

i) problem formulation; ii) exposure assessment; iii) hazard assessment; and iv) risk characterization.

Typically, where potential adverse impacts are predicted through risk characterization, an additional step providing risk management and recommendations for mitigative measures to address these concerns can be added, if necessary. This risk management step is an integral portion of the current EA process, to ensure the mitigation of any predicted potential health risks along the selected corridor candidate.

Receptor

Exposure HazardRisk



Figure 9-1 Overview of Standard Risk Assessment Framework

The proposed assessment will follow standard risk assessment methods, and will be conducted in compliance with the risk assessment procedures endorsed by regulatory agencies including Environment Canada, Health Canada, the Canadian Council of Ministers of the Environment (CCME), and the US EPA, as well as guidance provided by the Ontario Ministry of the Environment (MOE). These guidance include:

• Procedures for the Use of Risk Assessment under Part XV.1 of the Environmental Protection Act. Ontario Ministry of the Environment. Standards Development Branch. October 2005. (MOE, 2005);

• Rationale for the Development of Soil and Ground Water Standards for Use at Contaminated Sites in Ontario. April 15, 2011. Prepared by: Standards Development Branch, Ontario Ministry of the Environment. (MOE, 2011);

• Federal Contaminated Sites Risk Assessment in Canada. Part I: Health Canada Guidance on Human Health Preliminary Quantitative Risk Assessment (PQRA) (Health Canada, 2012a);

• Federal Contaminated Sites Risk Assessment in Canada. Part II: Health Canada Toxicological Reference Values (TRVs) and Chemical-Specific Factors Version 2.0 (Health Canada, 2010);

• Federal Contaminated Sites Risk Assessment in Canada. Part V: Guidance on Complex Human Health Detailed Quantitative Risk Assessment for Chemicals (Health Canada, 2009); and,

• The US EPA Human Health Risk Assessment Protocol (HHRAP) for Hazardous Waste Combustion Facilities. (US EPA, 2005).



9.1 Development of a Conceptual Model A Conceptual Model helps to define the nature and scope of the work to be conducted, permits practical boundaries to be placed on the overall scope of work, and ensures that the assessment is directed at the key areas and issues of concern. Typically, the development of a Conceptual Model is the result of completing the first step (the problem formulation phase) of a Human Health Risk Assessment (HHRA). The data gathered and evaluated during the development of the Conceptual Model typically provides information concerning human receptors of interest, sensitive receptor locations, chemicals of potential concern (COPCs), pathways by which receptors may be exposed to COPCs, and any other specific areas or issues of concern to be addressed (Figure 9-2). The key tasks requiring evaluation when developing a Conceptual Model include the identification of human receptors of interest; locating nearby sensitive receptor locations, developing an initial list of COPCs, and identifying exposure pathways (i.e., ways in which individuals may be exposed to chemicals in the environment).

Figure 9-2 Components of the Conceptual Model

9.1.1 Identification of Chemicals of Potential Concern A list of chemicals released into the atmosphere as a result of facility-wide air emissions from the proposed Southwestern facility, and emissions from facility vehicles using the haul roads, will be obtained from the Air Quality Study. Existing conditions data from the Groundwater/Surface Water Assessment Study will be used to develop an initial list of chemicals evaluated for the baseline (“background”) conditions. 9.1.2 Identification of Sensitive Human Receptors and Locations A human receptor is a hypothetical person (i.e., an infant, toddler, child, adolescent, or adult) who may reside, spend leisure time and/or work in the area being investigated and is, or could potentially be, exposed to the chemicals identified as being of COPCs. General physical and behavioural characteristics specific to the receptor type (e.g., body weight, breathing rate, food consumption rate, etc.) are used to approximate the amount of chemical exposure received by each receptor. The assessment must be sufficiently comprehensive to ensure that those receptors with the greatest potential for exposure to COPCs, and those that have the greatest sensitivity, or potential for developing adverse effects from these exposures, are included. With



this in mind, the selection of hypothetical, reasonable “worst-case” receptors, with somewhat exaggerated life style habits (to ensure a conservative assessment), will be developed for consideration in the HHRA. Due to differences in physiological characteristics and activity patterns between children and adults, the exposures received by a child and an adult will be different. Consequently, the potential risks estimated for the same COPC will differ depending on the receptor chosen for evaluation. For chemicals considered to be carcinogenic, it is common to assess exposure over a lifetime, as the development of cancer is a long-term process that may take many years to manifest itself. For this reason, a special type of receptor called a “lifetime” or “composite” receptor will be selected for evaluation of potential carcinogenic risks. This receptor is a “composite” of all relevant life stages for which exposure will be evaluated. In order to allow a comprehensive assessment of COPCs, five-age classes will be evaluated (as per Health Canada, 2012a):

i. Infant (0 to 6 months); ii. Preschool child or toddler (7 months to 4 years); iii. Child (5 years to 11 years); iv. Adolescent (12 to 19 years); and, v. Adult (20 years and over).

Receptors of concern will include residents of nearby houses and other sensitive receptors locations (e.g. schools, daycares, hospitals, retirement homes) that may fall within the Study Area. 9.1.3 Identification of Exposure Pathways People can come into contact with chemicals in their environment in a variety of ways, depending on their daily activities and land use patterns. The means by which a person comes into contact with a chemical in an environmental medium are referred to as exposure pathways. The means by which a chemical enters the body from the environmental medium are referred to as exposure routes. There are three major exposure routes through which chemicals can enter the body: inhalation; ingestion; and dermal absorption (i.e., uptake through the skin). For each of these major exposure routes, there are a number of potential sources of chemical exposure or exposure pathways:

• Direct inhalation of air containing COPCs through the lungs; • Ingestion of soil, dust, drinking water, garden produce, food; and, • Dermal absorption from soil, dust and water contact with skin.

Exposure pathways may require direct contact between receptors and the environmental media of concern (e.g., incidental ingestion of soil), or may be indirect requiring the movement of the chemical from one environmental medium to another (e.g., the uptake and/or transfer of a chemical from soil into home garden vegetables which are then ingested by an individual). Based on the available study area information, the above considerations, and professional judgment, the exposure pathways for inclusion into a quantitative HHRA will be determined. A number of different pathways may be identified, including:



Inhalation exposure pathways • Direct inhalation of COPCs in air and dust

Dermal exposure pathways

• Dermal contact with COPCs in soil and dust Ingestion exposure pathways

• Ingestion of COPCs in soil and dust • Ingestion of COPCs in drinking water • Ingestion of COPCs via consumption of backyard garden produce • Ingestion of COPCs via consumption of local livestock

The considerations and the information gathered as part of this task will be assembled to create an overall Conceptual Model for the HHRA moving forward (Figure 9-3).

Figure 9-3 Conceptual Model Example 9.2 Selection of COPCs for Quantitative Analysis It is common practice (within the context of an HHRA) to limit the number of chemicals evaluated to those that, due to their environmental concentrations, distribution, or chemical and toxicological properties, have the greatest potential to contribute to health risks to individuals residing in the study area. However, it is important to note that the identification of a substance as a COPC does not automatically lead to the conclusion that the substance is, in fact, a contributor to health risk. Rather, the appropriate conclusion is that those substances identified as COPCs should be the subject of further evaluation. It is preferable to comprehensively evaluate a smaller number of chemicals, which represent the greatest concern to people living



in the area under consideration, than it is to conduct a less detailed risk assessment on a larger number of chemicals. 9.2.1 Selection of COPCs in Air The existing conditions data generated by the Air Quality Assessment will provide predicted 1-hr, 24-hr and annual average ground-level air concentrations (as a result of facility-wide air emissions) for approximately 28 chemicals at a number of different receptor locations within the Study Area (i.e., within an approximate 5 km radius of the proposed Southwestern facility). Acute, sub-chronic, and chronic health risk estimates (via inhalation only) will be evaluated at each receptor location for all chemicals where an appropriate health-based regulatory air standard or toxicity value can be identified. Regulatory air standards are not always specifically designed to protect human health; some standards are designed to protect against corrosion, visibility or odour. Therefore, exceeding a regulatory air standard does not always indicate that the concentration is above that protective of human health. As a result, Intrinsik will review a number of different regulatory sources of air standards and inhalation toxicity data in an attempt to identify appropriate health-based criteria for as many chemicals as possible. Intrinsik will consider the following sources of information:

1. The Ontario Ambient Air Quality Criteria

An Ambient Air Quality Criteria (AAQC) is a “desirable concentration of a contaminant in air, based on protection against adverse effects on health or the environment. The term “ambient” is used to reflect general air quality independent of location or source of a contaminant.” (MOE, 2012a).

2. Summary of Standards and Guidelines to Support Ontario Regulation 419/05

“This document provides a list of air standards, guidelines and upper risk thresholds (URTs) that are used to assess the contribution of a contaminant to air quality from a single industrial or commercial facility in Ontario. This document is intended for use primarily by an emitter who is required to develop an Emission Summary and Dispersion Modelling (ESDM) report under Ontario’s Regulation 419/05…” (MOE, 2012b)

3. National Ambient Air Quality Objectives

“National Ambient Air Quality Objectives (NAAQOs) identify benchmark levels of protection for people and the environment. NAAQOs guide federal/provincial/territorial and regional governments in making risk-management decisions, playing an important role in air quality management (e.g. local source permitting, for air quality index and as benchmarks for developing provincial objectives and standards). NAAQOs are viewed as effects-based long-term air quality goals.” (Health Canada, 2012b)

4. Health Canada Toxicological Reference Values (TRVs) and Chemical-Specific Factors,

Version 2.0.

“Federal Contaminated Site Risk Assessment in Canada, Part II: Health Canada Toxicological Reference Values (TRVs) and Chemical-Specific Factors, Version 2.0 reflects numerous revisions to text and tables, relative to Version 1.0.” (Health Canada, 2010).



5. Toxicological Reference Values identified by the Ontario Ministry of the Environments in O. Reg. 153/07, as amended

“Rationale for the Development of Soil and Ground Water Standards for Use at Contaminated Sites in Ontario. April 15, 2011. Prepared by: Standards Development Branch, Ontario Ministry of the Environment. (MOE, 2011)”

In the event that Provincial and Federal air standards and/or toxicity values are unavailable for a particular chemical (e.g., some NAAQOs) or are deemed out-of-date, the following sources of inhalation toxicity values and standards will be considered:

• United States Environmental Protection Agency (US EPA) Integrated Risk Information System (IRIS). Available at: http://www.epa.gov/iris/;

• Office of Environmental Health Hazard Assessment (OEHHA). California Environmental Protection Agency. Available at: http://oehha.ca.gov/air/allrels.html;

• US EPA Region 9 (Pacific Southwest) Regional Screening Values. Available at: http://www.epa.gov/region9/superfund/prg/;

• United States Agency for Toxic Substances and Disease Registry (ATSDR). Available at: http://www.atsdr.cdc.gov/toxprofiles/index.asp; and,

• World Health Organization (WHO) and the International Programme on Chemical Safety (IPCS) – various sources including: http://www.inchem.org/; http://www.who.int/ipcs/en/; http://www.euro.who.int/en/what-we-do/healthtopics/environmental-health/air-quality

9.2.2 Selection of COPCs in Groundwater and/or Surface Water Existing conditions data from the Groundwater/Surface Water Assessment Study will be used to identify chemicals potentially released from proposed Southwestern facility to groundwater and/or surface water. Consideration will also be taken in the selection process for those elements of potential concern under current background conditions (e.g., fluoride). These data in combination with regulatory standards from the following sources will be used to select COPCs in groundwater and/or surface water:

• The Rationale for the Development of Soil and Groundwater Standards for Use at Contaminated Sites in Ontario (MOE, 2011) provides a series of potable and non-potable groundwater standards designed to be protective human health and the environment under different land use categories, including: Residential/Parkland/Institutional; Industrial/Commercial/Community; and, Agricultural or other Property Uses; and,

• Guidelines for Canadian Drinking Water Quality Summary Table. Prepared by the Federal-Provincial-Territorial Committee on Drinking Water of the Federal-Provincial-Territorial Committee on Health and the Environment. (Health Canada, 2012c).

In the event appropriate standards and/or toxicity values are not identified in these sources, alternate toxicity values and standards will be considered.

http://www.epa.gov/iris/

http://oehha.ca.gov/air/allrels.html

http://www.epa.gov/region9/superfund/prg/

http://www.atsdr.cdc.gov/toxprofiles/index.asp

http://www.inchem.org/

http://www.who.int/ipcs/en/

http://www.euro.who.int/en/what-we-do/healthtopics/environmental-



9.2.3 Selection of COPCs for Inclusion into the Multi-Media Assessment Due to differences in physical-chemical properties, not all chemicals emitted into the atmosphere by the proposed Southwestern Facility will be selected for quantitative analysis in every environmental media (e.g., soil, surface water, groundwater, etc.). To identify those chemicals in air that could persist or bioaccumulate in the environment, the physical-chemical properties of each of the COPCs will be compared against accepted national and international criteria for the classification of persistent and bioaccumulative substances (Environment Canada, 2006; Rodan et al., 1999). The classification of persistence and bioaccumulative are provided in detail in Environment Canada’s Existing Substances Program, and the Health Canada and Environment Canada Domestic Substances List Categorization, under the Canadian Environmental Protection Act (CEPA, 1999). Persistence refers to the length of time a chemical resides in the environment and is measured by its half-life. This is the time required for the quantity of a chemical to diminish or degrade to half of its original amount in a particular environmental medium. For a chemical to be considered as persistent, its half-life in soil must be greater than or equal to (≥) six (6) months or 182 days. Bioaccumulation is a general term used to describe the process by which chemicals are accumulated in an organism directly from exposure to water or soil. For example, the extent to which a chemical in soil has the ability to accumulate into vegetation. For a chemical to be considered to be bioaccumulative it must have an octonal-water partition coefficient (Log Kow) greater than or equal to five (5). A COPC identified in air will be retained for a full multi-media assessment in HHRA if:

• The COPC has a chemical half-life in soil greater ≥ 6 months or 182 days; and/or, • The COPC has an octanol-water partition coefficient (Log Kow) ≥ 5.

The basic principle of this exercise is that if a chemical that is emitted to the air does not meet either of the aforementioned criteria, the potential for the COPC to persist or accumulate in the environment is negligible, and only limited opportunity exists for exposure via secondary exposure pathways (i.e., those other than inhalation). However, if a chemical meets any one of the criteria, sufficient opportunity could be present for exposure via secondary pathways. 9.2.4 Developing the Final List of COPCs for Inclusion in the Quantitative HHRA As previously discussed, acute, sub-chronic, and chronic health risk estimates (via inhalation only) will be evaluated for all chemicals where an appropriate health-based regulatory air standard or toxicity value can be identified. Chemicals that meet the requirements of a persistent or bioaccumulative substance and show either an increasing trend in soil concentration or currently exist (in soil) above the Ontario Table 1 Standards (Full Depth Background Site Condition Standards – Agricultural or Other Property Use) will be evaluated in the multi-media HHRA. Chemicals identified in groundwater and/or surface water that exceed applicable health-based regulatory standards will be included in the quantitative HHRA. If a COPC is identified here that



has already been flagged for a mufti-media assessment, then these data will be integrated into the multi-media assessment. 9.3 Quantitative Human Health Risk Assessment Methods 9.3.1 Exposure Assessment The exposure assessment will evaluate data related to all COPCs, receptors and exposure pathways identified during the problem formulation phase. The primary objective of the exposure assessment is to predict, using site-specific data and a series of conservative assumptions, the rate of exposure (i.e., the quantity of chemical and the rate at which that quantity is received) of the selected receptors to the COPCs via the various exposure scenarios and pathways identified during development of the conceptual model. The rate of exposure to chemicals from many pathways is usually expressed as the amount of chemical taken in per body weight per unit time (e.g., µg chemical/kg body weight/day). The magnitude of exposure of receptors to chemicals in the environment depends on the interactions of a number of parameters, including:

• The concentrations of chemicals in various environmental media; • The physical-chemical characteristics of the chemicals of concern, which affect their

environmental fate and transport and determine such factors as efficiency of absorption into the body;

• The influence of site-specific environmental characteristics, such as geology, soil type, topography, hydrology, hydrogeology, local meteorology and climatology etc., on a chemical’s behaviour within environmental media; and,

• The physiological and behavioural characteristics of the receptors (e.g., respiration rate, soils/dusts intake, time spent at various activities and in different areas).

In order to evaluate potential exposures, it is necessary to characterize the physiological and behavioural characteristics of each receptor group. Several published sources will be considered in the selection of these parameters, including:

• Federal Contaminated Sites Risk Assessment in Canada. Part I: Guidance on Human Health Risk Preliminary Quantitative Risk Assessment (PQRA), Version 2.0. (Health Canada, 2012a);

• Rationale for the Development of Soil and Groundwater Standards for Use at Contaminated Sites in Ontario. Standards Development Branch, Ontario Ministry of the Environment. April 15th, 2011. (MOE, 2011);

• Compendium of Canadian Human Exposure Factors for Risk Assessment. O’Connor Associates Environmental Inc. 1155-2720 Queensview Dr., Ottawa, Ontario. (Richardson, 1997);

• Risk Assessment Guidance for Superfund Volume I: Human Health Evaluation Manual (Part E, Supplemental Guidance for Dermal Risk Assessment) Final. EPA/540//R/99/005. July, 2004. (U.S. EPA, 2004); and,

• The U.S. EPA Human Health Risk Assessment Protocol for Hazardous Waste Combustion Facilities. (U.S. EPA, 2005).

These sources have been used in numerous HHRAs that have been critically reviewed and accepted by regulatory agencies across Canada and the United States. Both the Compendium



of Canadian Human Exposure Factors for Risk Assessment (Richardson, 1997) and Health Canada (2012a) rely on data from published and reliable Canadian sources, such as Health Canada, Statistics Canada, and the Canadian Fitness and Lifestyles Research Institute. Where insufficient data are available in these sources to appropriately characterize relevant activity patterns and/or behavioural/physiological characteristics of a certain receptor group, other appropriate sources such as the U.S. EPA Exposure Factors Handbook (U.S. EPA, 2011) will be used to supplement the receptor parameter dataset, if necessary. Exposure Scenarios A key requirement of any HHRA is the ability to evaluate changing levels of exposure under a variety of different scenarios. Exposure scenarios describe the conditions in which receptors may be exposed to COPCs in the environment. In developing an exposure scenario, a variety of factors are considered including: potential for human access to specific areas or environmental media; physical activities / behavioural patterns; time spent in contact with exposure media (e.g., soil); other potential sources of exposure to COPCs; lifestyle factors (e.g., local produce consumption, fishing, and other uses of natural resources); and the potential of sensitive sub-populations or sensitive locations within a community (e.g., children at school, playgrounds; nursing homes). Several different exposure scenarios will be developed based on the likelihood that specific activities and behaviours are applicable to specific subpopulations. These hypothetical scenarios are deliberately selected to be conservative in nature (i.e., reasonable worst case), which helps to ensure that potential exposures to chemicals and the resultant risks are neither overlooked nor underestimated. The following are examples of possible exposure scenarios which may be evaluated by HHRA. Intrinsik will consult with other EA disciplines to gain further information as to the activities and types of individual receptors located within the Study Area (i.e., a 5 km radius) prior to finalizing the exposure scenarios to be evaluated. Examples of Potential Human Exposure Scenarios: Typical Residential Scenario: This scenario will consider people who live at nearby residential location(s) surrounding the proposed Southwestern Facility. The primary focus of this scenario will be on those “stay-at-home” receptors (e.g., infants, preschool children and adults that care for them, retired persons, etc.). It will be assumed that these receptors may occasionally leave the home area for such reasons as visiting, vacations, etc. The residential scenario will also look at a subset of the general population (i.e., avid gardeners and their families) who may consume significantly greater amounts of locally produced produce. Day Care / School Scenario: Both preschool and older children who may attend nearby day care, local schools and/or community centres will be evaluated. While at school, day care or a community centre, it will be assumed that children may play outdoors and come into contact with air, native soils and dust. While indoors, children should be assumed to come into direct contact with indoor dust, etc. Agricultural Scenario: Based on information provided to-date, the surrounding agricultural practices appear to consist primarily of cash crop operations. Intrinsik will work with agricultural and related disciplines to



determine whether or not other types of agricultural operations exist within the immediate vicinity of the proposed Southwestern facility, including small semi-subsistent farm operations that may raise livestock (e.g., beef and dairy cattle, pig, chicken, etc.). If it is determined that these types of small livestock operations exist with the Study Area (i.e., a 5 km radius from the proposed facility), the HHRA will consider this type of exposure scenario. 9.3.2 Toxicity Assessment Toxicity is the potential for a chemical to produce any type of damage, permanent or temporary, to the structure or functioning of any part of the body. The toxicity of a chemical depends on the amount of chemical taken into the body (referred to as the “dose”) and the duration of exposure (i.e., the length of time the person is exposed to the chemical). For every chemical, there is a specific dose and duration of exposure necessary to produce a toxic effect in humans (this is referred to as the “dose-response relationship” of a chemical). The toxic potency of a chemical (i.e., its ability to produce any type of damage to the structure or function of any part of the body), is dependent on the inherent properties of the chemical itself (i.e., its ability to cause a biochemical or physiological response at the site of action), as well as the ability of the chemical to reach the site of action (i.e., bioavailability). The dose-response principle is central to the HHRA methodology. There are two main types of dose-response relationships that are typically used for risk assessment of chemicals: Threshold Response Chemicals: For most effects, it is thought that there is a dose-response threshold below which no adverse effects would be expected to occur. This relationship is true for all chemicals that do not cause cancer by altering genetic material, including most metals. Thresholds are generally assumed for non-carcinogenic effects because, for these types of effects, it is generally believed that homeostatic, compensating, and adaptive mechanisms must be overcome before toxicity is manifested. Exposure limits derived for threshold-response chemicals are called reference doses (RfD), acceptable daily intakes (ADI), tolerable daily intakes (TDI) or permissible daily intakes (PDI) and are generally derived by regulatory agencies such as Health Canada and the U.S. Environmental Protection Agency (U.S. EPA). These values indicate doses of chemicals that individuals can be exposed to on a daily basis over an entire lifetime without appreciable risk of the occurrence of adverse health effects. Non-threshold Response Chemicals: For these chemicals, it is assumed that there is no dose-response threshold. This means that any exposure greater than zero is assumed to have a non-zero probability of causing some type of response or damage. This relationship is typically used for chemicals, which can cause cancer by damaging genetic material. Under a “no threshold” assumption, any exposure has some potential to cause damage, so it is necessary to define an “acceptable” level of risk associated with these types of exposures. The acceptable level of risk is a policy rather than a scientific decision, and is set by regulatory agencies, as opposed to risk assessors. In most jurisdictions, an incremental lifetime cancer risk (ILCR) level of less than 1-in-100,000 to 1-in-1,000,000 is considered a negligible risk level. Exposure limits for this project will be selected from reputable regulatory agencies, with recognized experience and expertise in the derivation of exposure limits to protect human health (e.g., Health Canada, U.S. EPA, ATSDR, WHO, Cal EPA OEHHA, OMOE, etc). The exposure limits selected for this HHRA will be scientifically defensible and those routinely accepted and used by government departments on HHRAs conducted in Canada and elsewhere. In selecting the limits, the scientific basis and date of last major review will be among the considerations.



9.3.3 Risk Characterization The risk characterization step integrates the exposure and hazard assessments to provide a conservative estimate of human health risk for the receptors assessed in the various exposure scenarios. Potential risk will be characterized through a comparison of the estimated or predicted chronic exposures from all pathways (from the Exposure Assessment) with the identified exposure limits (from the Hazard Assessment) for all chemicals of potential concern. For the COPCs which are non-carcinogens, this comparison is typically called the Exposure Ratio (ER) or Hazard Quotient (HQ) and will be calculated by dividing the predicted exposure level by the exposure limit (see equation below).

)(ug/kg/dayLimit Exposure

)(ug/kg/day Exposure Estimated (ER) Ratio Exposure =

Risk characterization for chemicals with a non-threshold-type dose response (i.e., carcinogens) consists of a calculation of the Incremental Lifetime Cancer Risk (ILCR), which is defined as the predicted risk of an individual in a population of a given size developing cancer over a lifetime. The ILCR is expressed as the prediction that 1 additional person per n people would develop cancer, where the magnitude of n reflects the risks to that population; for example, if the ILCR is 1 person per 10, the predicted risks of any individual developing cancer would be higher than if the ILCR is 1 per 1,000. The following equation provides the method whereby the ILCR is calculated: Incremental Lifetime Cancer Risk (ILCR) = Estimated Lifetime Exposure x Cancer

Slope Factor (q1*)

The resulting estimated cancer risk can then be compared to an acceptable risk level of cancer to determine if exposures to the assessed chemical pose an unacceptable health risk. In the Province Ontario, the acceptable risk level is 1-in-1,000,000. For chemicals with similar critical effects (i.e., those that act via a similar toxicological mechanism on a similar target tissue), individual ERs or ILCRs will be summed to reflect the combined risk level. Where COPCs have both cancer and non-cancer endpoints, risk estimates will be determined for both endpoints. The more sensitive of the two endpoints will be used to calculate land use specific PSSS for that particular COPC. In addition to the assessment of risks resulting from chronic, multi-media exposures, acute or short-term risks associated with the inhalation of COPCs in ambient air will be assessed through comparison with short-term (i.e., 1 hour or 24 hour) air quality guidelines. 9.4 Consideration of Chemical Mixtures Concurrent exposures to more than one chemical may result in toxicological interactions leading to several different possibilities in terms of combined toxicity. The combined toxicity may simply equal the sum of toxicities of the individual chemicals (additivity or independence), or may be greater (synergism or potentiation) or less than (antagonism) the sum that would be expected for additive or independent toxicity. Additive interactions apply to chemicals that are structurally similar, act toxicologically through similar mechanisms or affect the same target tissue in the body (i.e., share common effect)



(Health Canada, 2012a). The quantitative HHRA will identify potential additive interactions for specific COPCs. The health effect endpoint of the Toxicity Reference Values (TRVs) will provide the basis for an individual chemical’s inclusion in a chemical mixture. For example, it is common practice to group all carcinogenic polycyclic aromatic hydrocarbons (PAHs) and express incremental lifetime cancer risk (ILCR) estimates (in an additive manner) for the entire PAH group. 9.5 Uncertainty Analysis To properly provide a context for the risk characterization and interpretation of the results, an evaluation and discussion of the uncertainty associated with each element of the risk assessment will be provided in the HHRA.



10.0 REPORTING The Human Health Risk Assessment report will be structured to address each of the major objectives set out previously in Section 2 of this work plan. Also included in the report will be detailed appendices containing data and analyses carried out in the course of the study, along with other pertinent information to support the conclusions.



11.0 SUPPLEMENTARY HEALTH REVIEW In his review of the Terms of Reference, the Acting Medical Officer of Health for Oxford County, Dr. James Neal, identified the potential for health-related effects extending beyond those addressed through the HHRA, in particular “the inter-relationships of the social and economic constructs of the proposed landfill” (August 21, 2014). As a result, Walker proposed that an additional review of the social and economic impact assessment studies be carried out by the health expert, in consultation with Dr. Neal and Dr. Derek Hillis, the JMCC peer review health expert (September 12, 2014). The Minister adopted this recommendation in approving the Terms of Reference, adding the following amendment:

13. In addition to the proposed health risk assessment, Walker’s health expert shall carry out a screening-level review of the socio-economic assessment results to determine the potential for related health effects. Early in the environmental assessment process, prior to finalizing any work plans associated with the determination of health effects, Walker shall consult with the Joint Municipal Coordinating Committee and local medical officer of health to get input on the criteria and methods of assessment. As part of this consultation, Walker will discuss with the Joint Municipal Coordinating Committee and local medical officer of health, at a minimum, the determinants of health that will be assessed, and the different stages of assessment that will be undertaken including screening, scoping, assessment, mitigation, reporting and monitoring.

Walker shall provide detailed documentation of the issues and concerns raised in the finalization of the health studies work plans and the results. The documentation will include how those issues were considered, the steps that were undertaken to address comments received, where possible, and the rationale for why some comments may not have been addressed. If any significant negative effects are identified as part of the health studies, Walker's health expert will work closely with the social, economic and environmental experts, including the Joint Municipal Coordinating Committee and local medical officer of health, to determine what, if any, further studies are necessary and adapt or augment their mitigation recommendations to minimize or eliminate these potential effects, and characterize any residual net effects for the purposes of this environmental assessment. This decision-making will also be documented.

The following approach has been developed for completion of a Supplementary Health Review (SHR) within the Environmental Assessment (EA) for the proposed Southwestern Landfill. This approach is based on the steps identified by the MOECC, including: screening, scoping, assessment, mitigation, reporting and monitoring (Figure 11-1).



Figure 11-1 Steps of the Health Assessment (as identified by the MOECC) 11.1 Process Overview The screening step, which determines whether or not a health assessment is going to be conducted has already been completed, i.e., this health assessment is included in the EA. The scoping step, which identifies those determinants to be included in the SHR, has also been completed. The final list of determinants was selected based on Dr. Neal’s recommendations, in collaboration with Public Health Ontario (PHO), and included consideration of the public comments received from the Human Health Risk Assessment (HHRA) workplan. Since the HHRA workplan has already been finalized an approved, this component will not change and will follow the well-established HHRA process for assessing toxicological outcomes from exposure to various environmental media. Rather, the additional review will focus on those aspects of health that are not otherwise addressed through the HHRA and other EA studies, primarily related to social and economic factors as suggested by Dr. Neal. The next step of the process is to conduct the review and provide recommendations, where necessary. The process and results will be reported as part of the EA. This approach places the health assessment within the EA context, and not as a separate process, which is in line with Health Canada’s recommendation for including health in EA:

“Health assessment needs to be integrated in EA and not done as a separate entity because decision-makers require information on economic issues, health and environmental effects concurrently. As such, the obvious decision should be to perform all tasks simultaneously. It would be time consuming and often a duplication of information if one were to assess health separately from EA since information is often common for both. Equally important, the public expects health assessments to be part of the EA process” (Health Canada; Cited in Walker Correspondence, September 2, 2014).



11.2 Scoping Based on this integrated approach, each of the determinants is evaluated as part of the EA. The following table outlines the list of determinants to be assessed, the corresponding EA study and the assessment approach (Table 11-1). The review will evaluate the potential positive and negative health effects of each of the determinants, provided they are not already assessed through the HHRA and/or in another study within the EA. For example, the HHRA assesses potential health impacts of exposure to air, water and soil; therefore, the SHR will not re-assess these determinants, instead it will point to the appropriate section for reference. This approach will ensure streamlined integration of health into EA to address a wide range of health determinants without unnecessarily duplicating efforts. Table 11-1 Determinants and Approach

Health Determinants

Focus Areas

Corresponding EA Section Health Assessed?

Air

- Emissions

- HHRA

YES: Health effects from air emissions exposure assessed in the HHRA.

- Odour - Air Quality Study - Social Assessment

YES: Odour will be assessed in the SHR; using data and information from the Air Quality and Social studies, and supplemented with public health data and scientific literature.

Dust - Particulates - HHRA - Air Quality Study

YES: Health effects from dust exposure assessed in the HHRA and Air Quality study.

Water (groundwater and surface)

- Chemical exposures

- Recreational use

- HHRA - GW/SW Study

YES: Health effects from groundwater and surface water exposure assessed in the HHRA.

Soil - Chemical exposures

- Recreational use

- HHRA

YES: Health effects from soil exposure assessed in the HHRA.

Neighbourhood aesthetics

- Visual impact

- Visual Impact Study - Social Assessment

YES: Visual impact will be assessed in the SHR; using data and information from the Visual Impact and Social Assessments, and supplemented with public health data and scientific literature.

- Noise levels - Vibrations

- Noise/ Vibration Study - Social Assessment

YES: Noise and vibration will be assessed in the SHR; using data and information from the Noise and Vibration study and Social Assessments, and supplemented with public health data and scientific literature.

Pests - Vermin and wildlife

- Ecological Assessment

YES: Pests will be assessed in the SHR; using data and information from the Ecological Assessment, and supplemented with public health data and scientific literature.

Traffic - Emissions

- HHRA

YES: Health effects from traffic emissions assessed in the HHRA.

- Pedestrian safety - Traffic Study YES: Health effects from traffic safety assessed in the Traffic Study.

Economic - Property values - Employment - Municipal

revenues

- Economic Assessment

YES: Economic-related effects will be assessed in the SHR; using data and information from the Social Assessment, and supplemented with public health data and scientific literature.



Health Determinants

Focus Areas

Corresponding EA Section Health Assessed?

Social - Perception of hazards

- Recreational access and enjoyment

- Social Assessment

YES: Social-related effects will be assessed in the SHR; using data and information from the Social Assessment, and supplemented with public health data and scientific literature.

Social - Cultural heritage - Cultural Heritage Study

YES: Social/cultural-related effects will be assessed in the SHR; using data and information from the Cultural Heritage Study, and supplemented with public health data and scientific literature.

Built Environment - Land use planning

- Recreational spaces

- HHRA - Land Use Study

YES: Built Environment-effects effects will be assessed in the SHR; using data and information from the HHRA and Land Use study, and supplemented with public health data and scientific literature.

This list of determinants was recommended by the Medical Officer of Health and Public Health Ontario, and it coincides with the determinants and topics identified in several public comments received on the HHRA (Walker Correspondence dated April 2, 2014). 11.3 Assessment and Recommendations The assessment step of the SHR will include the following:

• A review of relevant EA studies (e.g., social and economic) to identify potential health effects;

• Characterization and assessment (quantitative and/or qualitative) of potential positive and negative health effects related to the construction and operation of the proposed Southwest Landfill, as per the Table above; and,

• Development of recommendations to enhance positive and mitigate negative effects on human health and well-being.

This approach to assessing health is to be based on the best available scientific evidence regarding health effects and will not be based on individual case studies or reports. As with the other EA studies, the SHR is a neutral and transparent evaluation of potential impacts. This is to ensure that the project considers protection of community health with respect to development and operations. Following completion and review of the relevant studies (e.g., social and economic) identified in the table above, a more detailed scope and plan will be developed to specifically address any potential issues from a health perspective, if and as required, in consultation with Drs. Neal and Hillis. All of the work associated with the HHRA and the Supplemental Health Review, along with related comments from Drs. Neal and Hillis, and from any other stakeholders, will be documented including Walker’s responses and resolution, as applicable.



12.0 REFERENCES CCME. 2012. Canadian Soil Quality Guidelines for the Protection of Environmental and Human

Health: Factsheets – Various Chemicals. Canadian Environmental Quality Guidelines. Canadian Council of Ministers of the Environment. Available at: http://ceqg-rcqe.ccme.ca

CEPA. 1999. Canadian Environmental Protection Act. Canada-wide Standards. Available at: http://www.ec.gc.ca/ceparegistry/agreements/cws.cfm.

CRA 2011. Conestoga-Rovers & Associates. Detailed Work Plan to Conduct Air Quality, Odour, and Noise Studies. Landfill Expansion Environmental Assessment. March, 2011.

Environment Canada. 2006. Domestic Substances List. Available at:

http://www.ec.gc.ca/substances/nsb/eng/cas_e.htm Health Canada. 2009. Federal Contaminated Sites Risk Assessment in Canada. Part V:

Guidance on Complex Human Health Detailed Quantitative Risk Assessment for Chemicals. Health Canada, Environmental Health Assessment Services, Safe Environments Programme.

Health Canada. 2010. Federal Contaminated Site Risk Assessment in Canada, Part II: Health

Canada Toxicological Reference Values (TRVs) and Chemical-Specific Factors Version 2.0. Health Canada, Environmental Health Assessment Services, Safe Environments Programme. September, 2010.

Health Canada. 2012a. Federal Contaminated Site Risk Assessment in Canada, Part I:

Guidance on Human Health Preliminary Quantitative Risk Assessment (PQRA). Health Canada, Environmental Health Assessment Services, Safe Environments Programme. Revised 2012.

Health Canada. 2012b. Regulations Related To Health And Air Quality. Health Canada. Accessed September 2012: http://www.hc-sc.gc.ca/ewh-semt/air/out-ext/reg_e.html.

Health Canada. 2012b. Guidelines for Canadian Drinking Water Quality Summary Table. Prepared by the Federal-Provincial-Territorial Committee on Drinking Water of the Federal-Provincial-Territorial Committee on Health and the Environment. August, 2012.

MOE. 1992. Interim Guide to Estimate and Assess Landfill Air Impacts. Air Resources Branch,

Ontario Ministry of the Environment. October 1992. MOE. 2005. Procedures for the Use of Risk Assessment under Part XV.1 of the Environmental

Protection Act. Ontario Ministry of the Environment. Standards Development Branch. October 2005.

MOE. 2011. Rationale for the Development of Soil and Groundwater Standards for Use at

Contaminated Sites in Ontario. Standards Development Branch, Ontario Ministry of the Environment. April 15th, 2011.

MOE. 2012a. Ontario’s Ambient Air Quality Criteria. Standards Development Branch. Ontario

Ministry of the Environment. April 2012. Available at: http://www.ene.gov.on.ca/environment/en/resources/STDPROD_096586.html

http://ceqg-rcqe.ccme.ca/

http://ceqg-rcqe.ccme.ca/

http://www.ec.gc.ca/ceparegistry/agreements/cws.cfm

http://www.ec.gc.ca/substances/nsb/eng/cas_e.htm

http://www.hc-sc.gc.ca/ewh-semt/air/out-ext/reg_e.html

http://www.ene.gov.on.ca/environment/en/resources/STDPROD_096586.html



MOE 2012b. Summary of Standards and Guidelines to Support Ontario Regulation 419/05 – Air Pollution – Local Air Quality (including Schedule 6 of O. Reg. 419/05 on Upper Risk Thresholds). Available at: http://www.ene.gov.on.ca/environment/en/resources/STDPROD_096528.html

MOEE 1994. Ministry of the Environment and Energy. 1994. Provincial Water Quality Objectives. Available at: http://www.ene.gov.on.ca/envision/gp/3303e.htm.

Richardson, G.M. 1997. Compendium of Canadian Human Exposure Factors for Risk Assessment. O’Connor Associates Environmental Inc. 1155-2720 Queensview Dr., Ottawa, Ontario.

Rodan BD, Pennington DW, Eckley N, Boethling RS. 1999. Screening for persistent organic

pollutants: techniques to provide a scientific basis for POPs criteria in international negotiations. Environ Sci Technol 33:3482–3488

U.S. EPA, 2004. Risk Assessment Guidance for Superfund Volume I: Human Health Evaluation

Manual (Part E, Supplemental Guidance for Dermal Risk Assessment) Final. EPA/540//R/99/005. July, 2004.

U.S. EPA 2011. United States Environmental Protection Agency. Exposure Factors Handbook:

2011 Edition. National Center for Environmental Assessment. Office of Research and Development US EPA, Washington DC 20460. EPA/600R-09/052F.

http://www.ene.gov.on.ca/environment/en/resources/STDPROD_096528.html

http://www.ene.gov.on.ca/envision/gp/3303e.htm



13.0 CONTACT INFORMATION Comments or questions regarding this draft work plan, or the Environmental Assessment, may be addressed through any of the following:

• Sending written comments by mail or fax to: Darren Fry Walker Industries 160 Carnegie Street

Ingersoll, ON N5C 4A8

• Sending an email with your comments to [email protected]

Additional information about the EA may be obtained at:

• The project web site: www.walkerea.com

• Calling the toll-free project number: 1-855-392-5537

• Registering to receive the Southwestern Landfill Proposal Newsletter and electronic updates by sending an email with your contact details to: [email protected]. You may also subscribe to the Newsletter by phone or mail.

mailto:[email protected]

http://www.walkerea.com/

mailto:[email protected]


HHRA and SHR Work Plan – Southwestern Landfill Proposal Environmental Assessment March, 2017 Intrinsik Corp. – Project #21325

Appendix A

Table A-1: Environmental Assessment Criteria and Studies


HHRA and SHR Work Plan – Southwestern Landfill Proposal Environmental Assessment March, 2017 Intrinsik Corp. – Project # 21325 Page A-1

Studies Addressing the Criteria Study Areas Duration

Criteria

Definition/ Rationale

Agric

ultu

re

Air Q

ualit

y

Arch

aeol

ogy/

Cu

ltura

l Her

itage

Ecol

ogy

Econ

omic

/ Fi

nanc

ial

Gro

undw

ater

/ Su

rfac

e W

ater

Hu

man

Hea

lth

Land

Use

Noi

se/V

ibra

tion

Soci

al

Traf

fic

Visu

al/

Land

scap

e

On-

Site

& S

ite

Vici

nity

Alon

g th

e Ha

ul

Rout

es

Wid

er A

rea

Ope

ratio

nal

Perio

d

Post

-Clo

sure

Pe

riod

Public Health & Safety 1 Explosive hazard due to

combustible gas accumulation in confined spaces.

Gas produced within a waste disposal facility (e.g., methane) can move through the ground and accumulate in confined spaces (e.g., manholes, basements, etc.) on or immediately adjacent to the waste disposal facility. There is potential for the gas to combust, creating an explosion and fire hazard.

2 Effects due to exposure to air emissions.

Waste disposal facilities can produce gases containing contaminants that degrade air quality if they are emitted to the atmosphere. Other operations, such as leachate collection facilities, can also produce emissions that could degrade air quality in the vicinity of the site. Air quality in the vicinity of the site should meet regulated air quality standards in order to protect public health.

3 Effects due to fine particulate exposure.

Construction, operation, and truck haulage activities at a waste disposal facility can lead to increased levels of particulate (dust) in the air. Airborne fine particulate is a health concern in certain size ranges exposure durations. The HHRA will also assess post-closure long-term impacts on soils from facility deposition during the operational period.

4 Effects due to contact with contaminated groundwater or surface water.

Contaminants associated with a waste disposal site have the potential to seep into the groundwater or surface water. This could pose a public health concern if it enters local drinking water supplies, or if it mixes with surface water.

5 Flood hazard. The construction of a waste disposal facility can disrupt natural surface water drainage patterns, causing a potential for increased flooding.

6 Disease transmission via insects or vermin.

Insects and vermin drawn to a waste disposal facility may have the potential to transmit diseases.




Criteria


Agric

ultu

re

Air Q

ualit

y

Arch

aeol

ogy/

Cu

ltura

l Her

itage

Ecol

ogy

Econ

omic

/ Fi

nanc

ial

Gro

undw

ater

/ Su

rfac

e W

ater

Hu

man

Hea

lth

Land

Use

Noi

se/V

ibra

tion

Soci

al

Traf

fic

Visu

al/

Land

scap

e

On-

Site

& S

ite

Vici

nity

Alon

g th

e Ha

ul

Rout

es

Wid

er A

rea

Ope

ratio

nal

Perio

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Post

-Clo

sure

Pe

riod

7 Potential for traffic collisions. The risk of traffic collisions may increase along the haul routes to the waste disposal facility. This includes the risk to pedestrian, bicycle and farm machinery.

Public Health & Safety (continued) 8 Aviation impacts due to bird

interference. Birds may be attracted to waste disposal facilities. This can pose a risk of bird strikes on aircraft in the vicinity of the site, especially during take-off and landing altitudes.

Social and Cultural 9 Displacement of residents

from houses. Any residents living on a future waste disposal site will have to relocate, which can cause inconvenience and stress to the residents.

10 Disruption to use and enjoyment of residential properties.

Potential nuisance effects associated with the waste disposal facility operation, or traffic moving to and from the waste disposal facility along the haul route, may disturb the daily activities and uses of residential properties. Disturbances could result from noise, dust, litter, odour, visibility, birds and t ffi ti

11 Disruption to use and enjoyment of public facilities and institutions.

Potential nuisance effects associated with waste disposal facility operations, or traffic moving to and from the waste disposal facility, may disturb the daily activities at community facilities. Disturbances could result from noise, dust, litter, odour, visibility, birds and traffic congestion.

12 Disruption to local traffic networks.

Increased traffic volume resulting from a waste disposal facility could disturb the overall traffic flow along the haul routes, and effectively reduce the available road capacity.

13 Visual impact of the waste disposal facility.

Development and operation of a waste disposal facility can affect the visual appeal of a landscape.

14 Nuisance associated with vermin.

Waste disposal facilities can attract vermin and birds, which can be a nuisance and lead to a decrease in property enjoyment by area residents. Vermin and birds can also be a nuisance to




Criteria


Agric

ultu

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Air Q

ualit

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Cu

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l Her

itage

Ecol

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Social and Cultural (continued) 15 Displacement/disturbance of

cultural/heritage resources. Cultural resources (including heritage buildings, cemeteries and cultural landscapes) are an important component of human heritage. These non-renewable cultural resources may be displaced by the construction of a waste disposal facility. The use and enjoyment of cultural resources may also be disturbed by the ongoing operation and traffic. Disturbances could result from noise, dust, odour, visibility, birds, litter and traffic congestion.

16 Effects on land resources, traditional activities or other interests of Aboriginal communities.

Major new developments of any type may have positive or negative effects on the interests of Aboriginal communities (i.e., businesses opportunities, joint ventures)

17 Displacement/destruction of archaeological resources.

Archaeological resources are non-renewable cultural resources that can be destroyed by the construction and operation of a waste disposal facility.

18 Level of public service provided by the waste disposal facility.

The presence of a waste disposal operation within a municipality can provide an increased level of public service (e.g., convenient access to waste disposal services) to local residents and businesses, as well as those in the broader community(ies).

19 Effects on other public services.

The presence of a waste disposal facility may have positive or negative spin-off effects on other public services in the community (e.g., leachate trucking, waste water treatment capacity, if there is discharge to the sewer system).

20 Changes to community character/cohesion.

Community character and cohesion refer to physical characteristics, social stability, attractiveness as a place to live and patterns of social interaction. A waste disposal facility may actually or perceptually interfere with these important community attributes.




Criteria


Agric

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Air Q

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Arch

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Cu

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itage

Ecol

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/ Fi

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Social and Cultural (continued) 21 Compatibility with municipal

land use designations and official plans.

A waste disposal facility has the potential to affect the viability of present and future land uses, which may have an effect on planning decisions made in the surrounding community.

Economics 22 Displacement/disruption of

businesses or farms. Any on-site businesses or farms would be displaced by a waste disposal facility, and there could be financial losses as a result of relocation. Some types of businesses located in the site vicinity or along the haul routes may suffer financial losses due to the potential nuisance effects or perceived effects associated with the operation of a waste disposal facility such as noise, litter, dust, odour, visibility, birds, vermin and traffic congestion.

23 Property value impacts. The establishment and operation of a waste disposal facility may adversely affect property values in the site vicinity or along the haul routes.

24 Direct employment in waste disposal facility construction and operation.

A waste disposal facility may create new employment opportunities both in the construction and day-to-day operation.

25 Indirect employment in related industries and services.

A waste disposal facility has the potential to have impacts on employment opportunities in local firms supplying products or services directly, or as secondary suppliers.

26 New business opportunities related directly to waste disposal facility construction and operation.

A large capital project, such as the construction and operation of a waste disposal facility, can create new opportunities for local businesses supplying products or services.

Economics (continued) 27 New business opportunities in

related industries and services.

New opportunities may be created for local businesses, or as secondary suppliers to industries working for the waste disposal facility (e.g., restaurants, gas stations, machine shops, repair shops, welding shops, equipment rentals, etc.).




Criteria


Agric

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Air Q

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Arch

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/ Fi

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28 Public costs for indirect liabilities.

Some public services may have to be upgraded to accommodate the establishment and operation of a waste disposal facility (e.g., snow removal, sewer and water connections, etc.).

29 Effects on the municipal tax base.

A waste disposal facility has the potential to affect municipal tax revenues from the site it occupies.

30 Effect on the cost of service to customers.

The costs of constructing a waste disposal facility will effect the price of tipping fees to the site. This affects the cost of service to customers in Oxford County and the Province.

31 Effects on the provincial/ federal tax base.

A waste disposal facility has the potential to affect provincial/federal tax revenues.

Natural Environment & Resources 32 Loss/displacement of surface

water resources. Construction of a waste disposal facility may cause the removal of all or part of a natural stream or pond.

33 Impact on the availability of groundwater supply to wells.

A waste disposal facility can impact the availability of groundwater supply if groundwater is pumped from aquifers or if recharge to aquifers is reduced.

34 Effects on stream baseflow quantity/quality.

The presence of a waste disposal facility has the potential to affect the quality or quantity of baseflow to surface water.

Natural Environment & Resources (Continued) 35 Loss/disturbance of terrestrial

ecosystems. Terrestrial ecosystems refer to the land-based habitats connected through the vegetation cover; their protection and integration maintains and regulates ecological health. Waste disposal facility operations and/or traffic may remove or disturb the functioning of these systems.

36 Loss/disturbance of aquatic ecosystems.

Aquatic ecosystems refer to the water-based habitats connected through the surface water; their protection and integration maintains and regulates ecological health. Waste disposal facility operations may remove or disturb the functioning of these systems.




Criteria


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37 Displacement of agricultural land.

The establishment of a waste disposal facility has the potential to displace existing or potential agricultural resources, including the loss of prime agricultural land.

38 Disruption of farm operations. The establishment and operation of the waste disposal facility may affect agricultural crop or livestock production and related agriculture activities

39 Sterilization of industrial mineral resources.

The establishment of a waste disposal facility may limit the opportunity to extract industrial mineral resources located beneath the site.

40 Displacement of forestry resources.

The establishment of a waste disposal facility may limit the opportunity to utilize forestry resources on or near the site.

41 Loss/disruption of recreational resources.

Waste disposal facility operations and traffic may displace/disrupt existing recreational resources in the area, which could adversely affect the community at large. Disturbances could result from noise, dust, odour, visibility, birds and traffic congestion. Recreational resources include naturalist and interpretive opportunities.


HHRA and SHR Work Plan – Southwestern Landfill Proposal Environmental Assessment March, 2017 Intrinsik Corp. – Project #21325

Appendix B

Disposition Tables – Comments on the Preliminary Work Plan

Walker Environmental Group Inc. Southwestern Landfill Proposal April 2, 2014

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HEALTH COMMITMENTS

The Town of Ingersoll October 15, 2013

s.5.8: Human Health Risk Assessment

1. Originally, the Draft ToR did not propose a Human Health Risk Assessment ("HHRA"). Following various concerns and objections from the interested public over WEG's failure to propose an HHRA, the ToR now provides for this technical study. However, the HHRA proposed in the ToR is not sufficiently rigorous, and should be amended to incorporate: a. An exposure assessment of on-site and off-site

receptors that could be affected by potential contamination; i) Provide a description of the characteristics of all

relevant on-site and off-site receptors;

Noted. These suggested clarifications will be considered as part of the revision and finalization of the technical work plan, in consultation with the peer review team, once the preferred alternative has been selected.

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ii) Receptor characteristics are defined to include: gender, age, predisposing physiological and/or medical conditions, and exposure variables (eg. breathing rate, water intake, etc.);

Noted. These suggested clarifications will be considered as part of the revision and finalization of the technical work plan, in consultation with the peer review team, once the preferred alternative has been selected. However, it should be noted that receptors evaluated in a quantitative HHRA are not typically based on actual existing individuals living within the Study Area. Rather they are evaluated based on hypothetical receptors with typical characteristics intended to generically assess a certain sensitive segment of the potentially exposed population. As such, predisposing physiological and/or medical conditions will not necessarily be evaluated based on receptor characteristics. Rather, sensitive individuals (i.e., individuals who have physiological and/or medical conditions that may predispose them to greater health risks from exposure) are accounted for through the use of Toxicity Reference Values (TRVs) for specific chemicals of concern that

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have been established by regulatory agencies to protect the most sensitive members of the population. The receptors and their respective characteristics used in the current HHRA will be based on the typical assumptions established by regulatory agencies, such as the Ontario MOE, Health Canada, and the US EPA, for human health risk assessments of this nature.


b. Consideration of receptors to the level of detail appropriate to meet the objective of the HHRA.

Acknowledged, see comment above. --


c. A pathway analysis for all potential contaminants. Any exposure pathway which can be anticipated based on chemical properties and site geology should be included.

Noted. These suggested clarifications, in the form of a detailed Conceptual Site Model (CSM), will be considered as part of the revision and finalization of the technical work plan, in consultation with the peer review team, once the preferred alternative has been selected. However, much of this analysis cannot be completed until detailed assessments have been conducted by the various other key disciplines (e.g., Air Quality, Groundwater/Surface Water, Agricultural, etc.) to provide the necessary information. Typically this type of pathway analysis is not conducted until the detailed risk assessment phase – not at the ToR phase of an EA.


d. Pathway analysis should address: i) sources for all potential releases;



ii) exposure media (including the air, surface water, groundwater, soil, sediment, biota);



iii) exposure points (i.e. where the potentially exposed population can come into contact with the contaminant); and



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iv) direct exposure routes (eg. ingestion, inhalation, dermal contact);



v) indirect exposure routes (eg. via intermediate receptors such as garden produce);



vi) transport of potential contaminants into the environment;



vii) exposure and distribution potential for all project phases;



viii) exposure and distribution changes during acts of god, including but not limited to floods, earthquakes, hurricanes, tornados.

This is beyond the scope of the proposed EA. --


e. Impact assessment of all potential contaminants with potential pathways:

Noted. These suggested clarifications will be considered as part of the revision and finalization of the technical work plan, in consultation with the peer review team, once the preferred alternative has been selected. The HHRA will provide detailed toxicological information on each of the Chemicals of Potential Concern (COPC) evaluated in the detailed assessment, including toxicological mode of action and potential carcinogenicity. However, much of this analysis cannot be completed until detailed assessments have been conducted by the various other key disciplines (e.g., Air Quality, Groundwater/Surface Water, Agricultural, etc.) to provide the necessary information on chemicals of concern. Typically this type of information is not provided until the detailed risk assessment phase – not at the ToR phase of an EA.

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i) state the potential adverse health effect on the human receptors potentially exposed to contaminants;



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ii) indicate whether the contaminants are carcinogenic;

Acknowledged, see comment above. ---


iii) describe and assess the probability of an adverse health if human receptors are exposed to the contaminant;

Acknowledged, see comment above. ------


iv) identify the toxicological end points (eg. developmental/ reproductive effects) and the time scale effects (eg. acute/chronic); and



v) identify and analyze the sources of uncertainty in the data used for the impact assessment;



vi) assume that all sources of uncertainty to be part of potential impacts.



2. Notwithstanding our comments above, there has not been a sufficient opportunity for the Town to consider the HHRA. Given how important an HHRA is in the EA process, the Town formally requests that there be an opportunity for further consultation on this item prior to the submission of the ToR for approval.

WEG has consulted on the HHRA with the JMCC and individually with the Medical Officer of Health.

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OPAL ALLIANCE October 2013 Received by WEG – November 19, 2013

Comments on the Human Health Risk Assessment Work Plan Key Issues:

Walker’s reluctance to include a Human Health Risk Assessment in their Environmental Assessment plans has been the cause of major concern for OPAL, the CLC, area municipalities and citizens and the Peer Review Team employed by the Joint Municipal Coordinating Committee and paid for by Walker Industries.

Walker’s scope of the HHRA work plan is very limited. Study durations do not include establishment of existing

baseline health of area citizens. The study areas as indicated by Walker are inadequate

around the site and haul route. Walker did not include comprehensive epidemiological

studies in their HHRA work plan.

These concerns are noted and are discussed further below. Issues related to preliminary study areas, cumulative effects and quarry rehabilitation are addressed extensively in response to previous comments in these tables.

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Walker’s work plan does not include study on what the human health implications would be of a catastrophic leachate breach and point---source contamination of our water supply from their proposed landfill.

Walker’s HHRA work plan does not adequately address cumulative impacts to our airshed.

The health implications of having a massive landfill situated in the middle of several of our communities within Oxford County, on top of the aquifer that supplies our drinking water and water for agriculture and food production is of paramount concern for Oxford residents, and this is not adequately represented in Walker’s work plans.

Real health concerns that are more difficult to quantify such as emotional stress and anxiety regarding the Walker/Carmeuse proposed landfill are completely ignored.

Loss of the environmental benefits of having additional trees, green---spaces and potential recreational areas has not been factored in to the study plans.

The County of Oxford Official Plan stipulates that Quarry Area rehabilitation must be of “net environmental gain” and prioritizes rehabilitation that “provide[s] significant social and environmental benefits”.


The first reason for concern regarding Walker Industries’ abilities to safeguard Oxford County stakeholders’ health is the fact that Walker Industries repeatedly refused to include a Human Health Risk Assessment in its Terms of Reference. Community stakeholders sitting on Walker Industries’ Community Liaison Committee repeatedly requested that a Human Health Risk Assessment be added to the ToR and Environmental Assessment, to no avail. Other community groups and hundreds of community members also insisted Human Health Risk studies be done. http://www.ingersolltimes.com/2013/05/08/county---asks---for---landfill---health---risk---study A County Council member, the

An HHRA is now included in the ToR, as a means to confirm to the community that the application of provincial standards to the EA studies is protective of human health.

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http://www.ingersolltimes.com/2013/05/08/county-


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Mayor of Ingersoll, asks for a landfill health risk study: “Living that close to a landfill, what are the effects? I’m not a scientist. I do not know but I certainly would like the health issue addressed… I think this is one of the major concerns of the residents of the area.” Community Consultation Appendices Open House pts 3---8 “The community has requested Health Risk Studies on concern checklists.” CLC Meeting # 5 Oct 3 2012 “… evaluate what the potential environmental and human health impact will be that would not otherwise be an issue if the proposed Landfill was established in our community?” From the Community Concern Checklist facilitated by OPAL and received by Walker from over 800 citizens who read over and signed the document: “As our local air quality in multiple areas of the county does not meet provincial minimum standards for particulate (particles in the air), we request that cumulative impacts from roads, quarries and the proposed landfill be assessed, including that particulate potentially created by the disposal of friable asbestos.” Additionally: “Landfills are known to produce many toxic gases including those known as “greenhouse” gases. We request studies be done on the potential health and environmental impacts of all landfill gases and emissions.” As well as: “We request a door---to---door study done with all residents within 5 km of the proposed landfill site to identify what the property is used for (organic vegetable gardens/childcare) as well as any health issues the residents are be dealing with.” Other health---related concerns raised: “As Canadian studies have shown an increase in cancer cases among people living close to landfill sites, we request a report on what a possible increase in cancer rates could mean to those communities that surround your proposed landfill site, including disease, disability, death, ability to earn a living and raise children, quality of life, and medical and support services costs.” As well as concerns related to bacteria and pathogens: “As landfills are known to attract vermin and pests such as gulls and rats, and they can carry diseases and pathogens, how do you propose to protect the local populations of citizens, domestic animals and livestock from these potential hazards?” And “As the landfill will be accepting waste from commercial establishments and institutions, how do you


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propose to protect the local population from any diseases or pathogens that might be contained in that “non---medical” waste? (Example: waste from airports that may contain international pathogens and diseases).” Finally, the Joint Peer Review Team prevailed upon Walker Industries to such a degree that Walker Industries relented and added what OPAL believes is an insufficient Human Health Risk Assessment. The corporation’s initial and prolonged position in this regard was unacceptable and disturbing.


Now that Walker Industries has included a Human Health Risk Assessment to the criteria being studied, the corporation’s ToR indicates the scope of the study is very limited and inadequate. It appears a token gesture on the part of Walker Industries. Among community stakeholders, the lightweight ToR fosters a lack of confidence in the corporation’s intentions and care and concern for the wellbeing of Oxford County. Further, Walker Industries’ Human Health Risk Assessment is not of the type or quality requested by multiple stakeholders. Resident stakeholders requested an epidemiological HHRA. Walker Industries did not comply and instead downgraded the request to a poor and unsatisfactory substitute. The inclusion of epidemiological studies would have provided more accurate information on the effects of Walker’s landfill proposal on the health of the citizens of Oxford, particularly those already suffering from the effects of the existing mega---quarry operations.

The HHRA has been developed by a recognized and experienced professional in the field, in consultation with the Oxford County Medical Officer of Health.

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Of the many problems present in the corporation’s Human Health Risk Assessment, most glaring is Walker Industries’ omission of the health consequences of a catastrophic event polluting the aquifer solely providing Oxford County’s drinking water, livestock water and general purpose water. Golder, Walker Industries’ consultants doing the Water risk assessment, has not identified this risk in its work plan, either, which indicates that the HHRA does not have to

OPAL’s opinion is noted; WEG intends to carry out the EA studies to properly assess any groundwater effects, which can then be examined appropriately in the HHRA.

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address the issue, according to Walker Industries’ ToR. This is one more reason why the ToR for the proposed landfill must be refused.


Our airshed is already polluted by particulate, dust, and emissions from the quarries in the area, including Carmeuse Lime, and the area cement plant. Cumulative impacts from the landfill would further degrade our air quality. Particulate and dust entering the air from the dumping, crushing, compacting, burying and spreading of trash, particularly industrial and construction/demolition waste, would contain silica and asbestos, two compounds that are carcinogenic and have the potential to cause or worsen other respiratory ailments such as COPD and asthma.

Carmeuse’s operations will be included in the baseline forecasts for this EA; see ToR Section 8.2.

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Walker Industries’ Terms of Reference Pg 14 states: “The Province of Ontario has historically noted issues with air quality in this area, particularly related to dust. Approximately 10 years ago, the local lime and cement industries in consultation with the MOE implemented a voluntary air quality monitoring program. Air quality monitoring has continued until the present. Although the MOE has expressed concern over the quality of some of this data, the results from this monitoring program will be reviewed by WEG, and if appropriate and with MOE consent, may be used to establish background air quality standards (subject to approval by the MOE).” In the above statement, Walker Industries drastically downplays and whitewashes the current situation. Proven by the Ministry of the Environment’s own documents, Carmeuse Lime’s operation in the Beachville area has a long history of withholding and hiding data that is to be revealed in Carmeuse’s regular reports to the MOE. Although the MOE released a very disturbing air quality report to the public in 2003 and committed to providing annual public reports thereafter, no reports have been produced. The MOE has said in written

As discussed previously in these responses, any historical air quality data will be critically evaluated by a qualified professional during the EA.

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statements made public that it cannot produce viable reports on air quality due to Carmeuse’s missing and questionable data. Therefore, Walker Industries cannot evaluate current conditions impacting human health risks and establish a baseline for Walker Industries’ projections by using Carmeuse data. The MOE’s revelations regarding Carmeuse Lime’s non---compliance in providing regular data to the MOE has proven to residents impacted by Carmeuse’s ongoing quarry operations that allowing an operator to be its own watchdog is not effective in protecting the human health of residents and workers on site and in the surrounding communities. Indeed, this broken system is allowing the fox to guard the henhouse – and the hens and their chicks are suffering. Attempts from OPAL and area residents to obtain follow---up air quality information have been evaded by the MOE’s Southwestern Regional office since June of 2012, and more recently through delays in fulfilling a Freedom of Information request. In view of the vague and apparently evasive responses presented by Walker Industries to Oxford County residents, the Walker Community Liaison Committee, OPAL Alliance and other stakeholders, there is no reason to believe Walker Industries would be more responsible and accountable than Carmeuse in its monitoring and reporting of operational data vital to the protection of human health.


Looking at Walker Industries’ Figure 5 Preliminary Study Area(s) Map on page 21 of Walker Industries’ Terms of Reference, the areas identified for study pertaining to groundwater and surface water area are very small. Since science has shown that all landfill liner systems, including modern versions, eventually leak, toxic leachate will travel far beyond the limited study areas. As mentioned above, the proposed landfill site is situated over a Highly Vulnerable Aquifer system and Significant Groundwater Recharge Area that provides water for Oxford County wells, both private and public, the area’s only source of fresh water. The

This matter is discussed at length in these responses; see above.

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proposed landfill site is also right beside the Canadian Heritage Thames River, an important part of the Great Lakes Waterway.


Walker Industries’ limited scope of study is irresponsible and dangerous. Additionally, there is inadequate study proposed in the HHRA plan for potential effects of exposure to chemicals of concern including rare earth elements (REE), which are becoming more common in landfills due to the disposal of technological devices such as cell phones.

The HHRA has been developed by a recognized and experienced professional in the field, in consultation with the Oxford County Medical Officer of Health.

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Walker Industries states in its Human Health Risk Assessment work plan on Pg. 3: “….the following are the primary environmental assessment criteria that are to be addressed in the Human Health Risk Assessment: Effects due to exposure to air emissions; Effects due to fine particulate exposure; Effects due to contact with contaminated groundwater or surface water. Furthermore, this study is also designed to provide key input/data to other environmental criteria that will be addressed through studies conducted by other experts. These criteria include: Disruption to use and enjoyment of residential properties – Social/Cultural; Disruption to use and enjoyment of public facilities and institutions – Social/Cultural; Disruption of Farm Use – Agricultural; and Property value impacts – Social/Cultural.” In identifying its criteria, Walker Industries focuses only on human health effects due to exposure to air emissions and fine particulate and contact with contaminated groundwater or surface water. In regard to use, enjoyment and value of residential, public, institutional and agricultural properties, Walker Industries focuses only on the “health implications of emissions” and ignores other adverse impacts on human health that the proposed landfill would cause.

• Emotional wellbeing gained by living in a healthy home and community

All of these concerns are noted and are important. By and large these are all issues that are the subject of the proposed social impact assessment (refer to Appendix B, Table A-1, Criteria 10, 11, 20, along with the preliminary social assessment work plan). As referenced extensively in previous responses here, the EA studies are designed to be fully integrative between disciplines (for reference, see Table A-2, Appendix B to the ToR); therefore, we intend that the social and health assessments will be coordinated in such a way to characterize the potential for any socially related health effects.

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• Stress relief gained by time spent outdoors in fresh, good quality air and natural settings (not possible when a landfill causes stench; draws thousands of birds flying to and from the dump; attracts disease---carrying vermin; and other threats to human health)

• Development and maintenance of healthy lungs and immune systems benefitting from clean, pure---smelling air to breathe, indoors and outdoors

• Healthy exercise taken outdoors in local conservation areas, parks and walking trails

• Mind, body and spirit benefits that are naturally derived from living in a holistic community that strives to advance and enhance healthy lifestyle choices

• Therapeutic benefits of time spent with family, friends and neighbours

• Support systems secured by family members staying in community, providing emotional support, childcare, eldercare, preservation and continuation of the family homestead

• Emotional wellbeing generated by being part of an established and continuing community (As residents living near Walker Industries’ Thorold/Niagara waste management campus informed Oxford County residents at a public meeting in 2012, Walker Industries will destroy your community as they destroyed ours).

• Sense of security, self---esteem and belonging through the continuation of the family farm

• Positive benefits of recreation, exercise and relaxation gained at the Carmeuse lakes (a series of five lakes), and “recreational quality” green spaces on rehabilitated quarry lands, in accordance Carmeuse Lime’s Aggregate Resources Act legal rehabilitation requirements and in keeping with the County of Oxford Official Plan. (Carmeuse representatives have long promised residents the lakes, particularly the existing Quarry Lake (identified as an ES---ANSI), would soon be public attributes providing recreational swimming, fishing and canoeing;


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and its surrounding rehabilitated green space would provide walking trails, camping and picnic grounds. Instead, Carmeuse is planning to drain the lake, which currently teeming with bass, trout and other fish and is a haven to birds; and is continually refreshed by water pouring through karst fissures and tunnels in the rock walls. Walker Industries wants the lake area to be part of the landfill’s buffer/containment attenuation zone. The proposed draining of the lake by Carmeuse, prior to commencement of an EA sought by the Walker, seems to be a suspiciously convenient way for them to avoid studying interactions between the quarry lake and local groundwater).

The above benefits of Quarry Area and Limestone Resource Area rehabilitation are supported by the County of Oxford Official Plan, Section 3.4.1.3.4, After---Use Priorities and Rehabilitation Policies, which dictates that: “Where it can be shown that it is not feasible to return the lands to Classes 1 to 3 agricultural capability, according to the Canada Land Inventory, and in keeping with the principle of net environmental gain as established in this Section, second priority shall be given to rehabilitation which provide significant social and environmental benefits, including but not limited to the following:

• wetlands systems • wildlife habitat and linkages • reforestation • surface water systems • passive recreation.”

Walker Industries’ Human Health Risk Assessment work plan also fails to consider the following currently occurring health risks prompted by Walker Industries’ landfill proposal process:

• Anxiety, fear, frustration and anger experienced by residents confronted by the negative factors of Walker Industries’ landfill proposal


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• Residents who have to take sleeping medication and anxiety prescription medications to help them deal with the stress caused by Walker Industries’ landfill proposal

• Loss of restorative personal and family time experienced by community members who volunteer to oppose Walker Industries’ landfill proposal

• Siphoning of volunteer time and resources from other community groups and charities that provide health benefits to residents, as volunteers are now working to stop Walker Industries’ landfill proposal

• Fatigue, burn out and migraine, compromised immune systems and resultant contracted diseases caused by stress and overwork in volunteers combatting Walker Industries’ landfill proposal

• Physical toll taken on the bodies and health systems of residents who had planned on retiring but since Walker Industries’ landfill proposal has already devalued their homes, these residents must work longer than they intended

• Concern about the real threat that some local medical doctors will leave Oxford County and practice elsewhere if Walker Industries’ landfill is approved. (One doctor has already publicly made her position regarding relocating her practice should Walker Industries’ landfill become reality. Other doctors are discussing the issue).

Walker Industries’ evident disregard for the holistic health of human stakeholders is further reason for the Ministry of the Environment to reject Walker Industries’ landfill proposal once and for all.


The Study Areas identified by Walker Industries’ Human Health Risk Assessment work plan are too vague and non---committal: Page 5 “The wider area, generally beyond the immediate site vicinity. Depending on the particular criterion this may include neighbourhoods, local municipalities, Oxford County, or the Province.” That gives no assurance to stakeholders that their areas are actually going to be studied; the “may” and “generally”

The definitions are from the ToR, and are meant to describe three general study areas (for the whole EA; See ToR, Section 6.2). Each technical study then adapts and employs specific definitions of these study areas suited to their particular assessment. Obviously, the HHRA study areas will be an amalgam of the other studies from which it obtains

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language is not satisfactory. Additionally, the proposed study area around the haul routes is too limited.

its input, and therefore will be adapted and refined as the EA progresses.


Walker Industries eliminates many critical criteria from its Human Health Risk Assessment study – Pgs A---1 to A---6: Public Health & Safety: Explosive hazard due to combustible gas accumulation in confined spaces (could cause injury, disability and death to site workers and residents in surrounding communities); Flood hazard (could cause mold in the home, displacement, death); Disease transmission via insects or vermin (causing infection, disease and death); Potential for traffic collision (causing injury, disability and death); Aviation impacts due to bird interference (causing injury, disability and death). Social and Cultural: Every one of the criteria has impact on resident stakeholders’ health and wellbeing. Economics: Displacement/disruption of businesses or farms; Property value impacts. (These also impact stakeholders’ health and wellbeing). Natural Environment & Resources: Loss/displacement of surface water resources; Impact on the availability of groundwater supply to wells; Effects on stream baseflow quantity/quality; Loss/disturbance of terrestrial ecosystems; Loss/disturbance of aquatic ecosystems; Displacement of agricultural land; Disruption of farm operations; Displacement of forestry resources; Loss/disruption of recreational resources. (These also impact stakeholders’ health and wellbeing). By not dedicating specific study to each of the above criteria, Walker Industries is clearly not giving due examination and weight to its proposed landfill’s impacts on human health. Considering these omissions and Walker Industries’ downplaying the significance of risks the proposed landfill will present to human health, it is reasonable to assume Walker Industries’ assessment studies will be of poor quality, flawed and deficient in science.

In fact, there is a specific study dedicated/assigned to each of the EA criteria; see ToR, Appendix B, Table A-1. Furthermore, as discussed extensively in these responses, the EA studies are designed to be fully integrative between disciplines (for reference, see Table A-2, Appendix B to the ToR).

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Therefore, the ToR for Walker Industries’ landfill proposal should be rejected and refused outright.

HHRA WORK PLAN DISCIPLINE: HUMAN HEALTH RISK ASSESSMENT WEG PRT WEG ACTION

Comments Received by Reference Comment (May 9, 2013) Response Revision

(Aug 29, 2013) Response Response

JMCC Peer Review Received by WEG – November 19, 2013

TOC/pre-report body

Editorial Comment. A List of Acronyms at the beginning or end of the work plan would aid readers/reviewers unfamiliar with those acronyms regularly used in a human health risk assessment.

Agreed. A List of Acronyms will be provided in the detailed work plan and formal HHRA report.

Work Plan to be revised and finalized during EA

Accept subject to review of the work plan

Agreed Agreed. A List of Acronyms will be provided in the detailed work plan and formal HHRA report.


5.0/6 1/5 Editorial Comment. sp. “re-entrained” versus “retrained”

Thank you. This typo will be corrected.



Agreed Thank you. This typo will be corrected


6.0/7 and throughout the work plan

The authors regularly refer to the evaluation of acute, sub-chronic and chronic health-based benchmarks. The reviewer believes the evaluation of subchronic benchmarks will be difficult based on the air concentration data provided by the air modeling typically used to support Air Quality Assessments. The authors note that the modeling periods will be 1-hr., 24- hr. and annual average concentrations, which are most appropriately compared to acute (1-hr. & 24-hr. average

In many cases, the 24-hour exposure duration is referred to either as acute or sub-chronic, depending on its application. It was grouped in that fashion in the workplan to allow better distinction between the different time periods, but really has no bearing on the ultimate predictions of risks. However, for the sake of clarity, the 24-hour

-- Accept subject to review of the work plan

Agreed However, for the sake of clarity, the 24-hour exposure period will be grouped into the acute exposure review, and the sub-chronic review will be removed, as suggested by the reviewer.


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concentrations) and chronic (annual average concentrations) health-based criteria. The reviewer suggests that the authors focus the human health risk assessment on acute and chronic timeframes and remove the sub-chronic review from the work plan. Removal of the subchronic evaluation will not impact the conservatism or robustness of the risk assessment conclusions.

exposure period will be grouped into the acute exposure review, and the sub-chronic review will be removed, as suggested by the reviewer.


8.2.1/14 Comment to improve transparency re: Selection of COPCs in Air. Is a preference to be given to health-based standards with respect to their source? For example, will MOE O. Reg. 153/04 TRVs take precedence over Health Canada TRVs or O. Reg. 419/05 health-based standards, or will each be given equal preference and selected based on scientific merit with respect to their development? Please clarify.

As this is an EA project submitted in the Province of Ontario, and subject to approval by the MOE, typically TRVs recommended by the MOE under O. Reg. 153/04 will be given precedence, except in those cases where other reputable regulatory agencies have provided updated TRVs based on more recent scientific review. In the cases where the selected TRV deviates from those recommended by the MOE under O. Reg. 153/04, the HHRA will include a detailed toxicological profile which

-- Accept subject to review of the work plan.

Agreed --


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will provide justification for the deviation.


8.2.4/16 2 Comment to improve transparency re: COPC Selection. With respect to the sentence “Chemicals that meet the requirement of a persistent or bioaccumulative substance and show either an increasing trend in soil concentration or currently exist (in soil) above the Ontario Table 1 Standards will be evaluated in the multi-media HHRA”, it is unclear where the soil data to show an “increasing trend” or “currently exist above the Ontario Table 1 Standard” will be obtained. There do not appear to be biomonitoring or soil studies currently available in support of the EA to allow an evaluation of trends or current soil concentrations. If the concentrations are to be “predicted” to complete the evaluation of trends or current soil concentrations, a brief description of which method to be employed should be provided.

At this time, biomonitoring or soil studies are not contemplated as part of the EA. It is not anticipated that chemicals potentially emitted by the facility would be present in elevated concentrations in the area surrounding the proposed project given historic and existing industry in the area. Soil concentrations over time throughout the proposed lifetime of the project will be estimated using standard US EPA recommended approaches in their combustion risk assessment protocols that has been previously accepted by the MOE in similar EA projects. A detailed worked example of the calculations will be provided as part of the HHRA documentation.

-- Accept subject to review of the work plan.

Agreed

JMCC Peer Review

8.3.1/17 Comment to improve transparency re: Exposure Assessment. Is a preference to be given to receptor

As this is an EA project submitted in the Province of Ontario, and subject to


Agreed --


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Received by WEG – November 19, 2013

characteristics and exposure estimate algorithms with respect to their source? For example, will MOE O. Reg. 153/04 assumptions take precedence over Health Canada assumptions or U.S. EPA assumptions, or will each be given equal preference and selected based on scientific merit with respect to their development? Please clarify.

approval by the MOE, typically receptor characteristics and exposure estimate algorithms recommended by the MOE under O. Reg. 153/04 will be given precedence, except in those cases where site-specific conditions may suggest more conservative values based on stakeholder feedback.


8.3.2/19 Comment to improve transparency re: Toxicity Assessment. There is no discussion in the toxicity assessment on the methodology used to determine how a compound will be designated as a non-carcinogen (threshold) or carcinogenic (non-threshold) compound. Will it be assumed that for compounds where an IUR and/or Oral SF was adopted by the MOE that the substance will be deemed carcinogenic? If a COPC is not included in the MOE O. Reg. 153/04 Rationale document, the report should indicate that the compounds will undergo a screening of IARC, USEPA or NTP carcinogenicity classifications. Please clarify.

If an emitted chemical has an IUR and/or oral SF adopted by the MOE, this chemical will be deemed carcinogenic and evaluated based on the IUR/SF provided under O. Reg. 153/04. If the MOE does not view it to be a carcinogen, or does not have a TRV for that particular chemical, consideration will be given to other reputable regulatory agencies (as noted in the workplan) as to the chemical’s status and potential TRVs to use in the HHRA.


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8.3.3/20 Comment to improve transparency re: Risk Characterization. Acceptable ER limits associated with the threshold-based inhalation and multi-media risk characterizations should be defined.

Inhalation exposures will be evaluated based on a concentration ratio (CR) comparing inhalable chemical concentrations to the appropriate regulatory benchmark. If the concentration exceeds the benchmark (i.e., CR > 1), a further discussion of potential health risks related to these exposures will be provided. For multimedia risk characterizations, the overall Exposure Ration will be compared to a benchmark of 0.2 (i.e., 20% of the TRV) to account for other potential exposure sources unrelated to the proposed Project.


Agreed


8.3.3/20 5/4-5

Editorial Comment. It is unlikely that an objective of this HHRA is to develop PSSs. We suggest the sentence “The more sensitive of the two endpoints will be used to calculate land use specific PSSs for that particular COPC” should be removed.

Agreed. This sentence was mistakenly included, and will be removed.



Agreed Agreed. This sentence was mistakenly included, and will be removed.


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8.3.3/21 Comment to improve transparency re: Mixtures. When discussing the additive interactions of compounds sharing similar mechanisms or target organs and for which Toxic Equivalency Factors (TEFs) do not exist, the authors should be more explicit as to the process and indicate that additive interaction based TEFs will be assumed to be on a 1 to 1 ratio (or other ratio) unless other evidence is available.

Where information on TEFs is available from reputable regulatory agencies, these will be used in the mixture assessment. Otherwise, the HHRA will assume an additive interaction-based approach where each chemical in the mixture has a TEF of 1, assuming they act through the same toxicological mode of action.


Agreed --

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