updating ontario’s regulatory framework for local air...

Ministry of the Environment

Updating Ontario’s Regulatory Framework for Local Air Quality

A Position Paper

Proposed amendments to Ontario Regulation 346 (under the Environmental Protection Act) to introduce new standards, update air dispersion models and provide a risk-based decision making process to address implementation issues

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The results from this consultation would be used to move forward with the amendment of Regulation 346. The comment period for this document is 120 days from the date it was posted on the Environmental Registry. Please submit your comments to:

Public consultation document under the Environmental Bill of Rights, 1993 EBR Number: EBR # Ministry Contact:

Ministry of the Environment Standards Development Branch Attention: Cathy Grant, P.Eng., Coordinator - Air Standards (Engineering Specialist) 40 St Clair Ave West, 7th floor Toronto, Ontario M4V 1M2 Phone: (416) 327-6600 Fax: (416) 327-2936 mailto:[email protected]

Additional Comments:

This document that accompanies this proposal is provided solely to facilitate public consultation under section 15 of the Environmental Bill of Rights, 1993. Should the decision be made to proceed with the proposal, the comments received during consultation would be considered during the final preparation of the policy. The content, structure and form of the draft document are subject to change as a result of the consultation process.

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Executive Summary

We are delivering real, positive change to protect the health of Ontarians. Clean safe air is essential in protecting the health and environment of our people and our communities. The Ontario government is setting clear goals for cleaning up the air Ontarians breathe. The Ministry of the Environment is committed to establishing effects-based air standards to ensure cleaner air for local communities. We continue to focus on finding solutions to problems that pose the greatest risk to human health and the environment. This document is a follow up from previous consultation in 2001 on improving implementation of air standards. The Ministry of the Environment (MOE) is now proposing the following guidelines and regulatory amendments to enhance the development and implementation of air quality standards in Ontario:

• “Guideline for the Implementation of Air Standards in Ontario” (GIASO), a risk-based decision making process to deal with implementation barriers associated with the introduction of new/updated/revised air standards and new models

• an “Air Dispersion Modelling Guideline for Ontario” (ADMGO), which introduces guidance for dispersion modelling in Ontario

• a position paper on “Updating Ontario's Regulatory Framework for Local Air Quality”, which outlines proposed regulatory amendments.

This position paper outlines proposed regulatory amendments required in order to:

• continue the updating/revising/development of air quality standards;

• phase-in the introduction of new air dispersion models and new standards;

• introduce air standards into the regulation with different averaging times (i.e. Ambient Air Quality Criteria or AAQCs) (see Appendices);

• deal with implementation barriers associated with timing, technology and/or economics using a risk-based decision making framework that includes public input; and

• improve the clarity and enforceability of the regulation in order to better implement air standards and protect local air quality in Ontario.

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Table of Contents

Executive Summary ...................................................................................................... 3

Table of Contents.......................................................................................................... 4

1.0 Introduction......................................................................................................... 5

2.0 Ontario’s Regulatory Framework ...................................................................... 7 2.1 Background – Previous Consultation ................................................................ 8

3.0 Ontario’s Air Standards ..................................................................................... 9

4.0 New Air Dispersion Models ............................................................................. 11 4.1 Introducing effects-based averaging times ..................................................... 12

4.2 Implementation issues with new models......................................................... 14

4.3 Proposal to update Emission Estimation Methodology ................................... 15

5.0 A Proposed Guideline for the Implementation of Air Standards in Ontario 16 5.1 More Effective Implementation of Regulation 346........................................... 19

6.0 Other regulatory amendments ........................................................................ 20

7.0 Consistency ...................................................................................................... 21

Appendix A: Proposed Revisions - Reg 346 Schedule 1 ...................................... 22

Appendix B: Proposed Revisions - Reg 346 Schedule 2 ...................................... 25

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1.0 Introduction

For over 30 years, Ontario's Ministry of the Environment (MOE) has been in the business of protecting Ontario's local air quality. Regulation 346 (General - Air Pollution) is the cornerstone of local air quality protection efforts. Under its authority, the MOE sets and enforces standards for a large number of air pollutants in order to protect against impacts such as cancer, respiratory effects and even odour. Compliance with Ontario's air standards is traditionally measured at the Point of Impingement (POI) of the facility that is the source of the emission. Mathematical air dispersion models are used to predict maximum ground level concentrations or POI concentrations at locations in the vicinity of facilities that emit contaminants into the air. These concentrations are then compared to the MOE’s air quality standards(1) to assess compliance.

Since 1996, MOE has been updating/revising air quality standards as outlined in the Standards Plan (revised 1999). MOE recognizes that not all standards can be achieved immediately because of technology and/or economic considerations or simply the need for more time to plan, design and install equipment and/or process changes. In 2001, MOE proposed to phase-out existing Regulation 346 air dispersion models and replace them with a suite of United States Environmental Protection Agency (US EPA) air dispersion models. Transition to the proposed new air dispersion models will also require time. In many situations, a phase-in period for new standards and new models will provide facilities enough time to assess, plan, and if necessary budget for changes to their processes in order to comply.

The development of new or revised air quality standards and introduction of new air dispersion models that more accurately predict concentrations at a POI means that some facilities may be out of compliance even though they have not made any changes in emissions from their facility. In order address these issues, in March 2001, MOE consulted on two discussion papers: “A Proposed Risk Management Framework for the Air Standard Setting Process in Ontario” and “Updating Ontario’s Air Dispersion Models” (available on the MOE website at: www.ene.gov.on.ca/envision/env_reg/er/documents/2001/airstandards/pa9e0002.htm).

1 Standards can be found in Schedule 1 of Regulation 346. These standards and other guidelines are listed in the MOE publication, “Summary of Point of Impingement Standards, Point of Impingement Guidelines and Ambient Air Quality Criteria (AAQCs), Standards Development Branch, Ministry of the Environment”, dated September 2001 (or most recent revision).

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http://www.ene.gov.on.ca/envision/env_reg/er/documents/2001/airstandards/pa9e0002.htm


MOE received and considered numerous comments regarding these postings. These comments, along with the existing experience within MOE, were considered in the development of these proposed guidelines and regulatory amendments. Since the 2001 proposals, MOE has done the following:

• continued to consult on high priority air standards including 15 air standards information drafts that were posted December 2002;

• developed a technical publication entitled: Consultants' report: Proposed Guidance For Air Dispersion Modelling (November 2003) - Publication #: 3614e02 (http://www.ene.gov.on.ca/envision/techdocs/3614e02.pdf );

• developed regional meteorological data files and terrain data for Ontario to use as inputs into the US EPA models; and

• conducted a pilot project with five industrial facilities and a non-government organization to test a risk-based decision making process to deal with implementation barriers associated with air standards.

MOE is now proposing the following guidelines and regulatory amendments to enhance the development and implementation of air quality standards in Ontario:

• the “Guideline for the Implementation of Air Standards in Ontario” (GIASO)

• an “Air Dispersion Modelling Guideline for Ontario” (ADMGO)

• this position paper on “Updating Ontario's Regulatory Framework for Local Air Quality”.

This position paper outlines proposed regulatory amendments required in order to:

• continue the updating/revising/development of air quality standards;

• phase-in the introduction of new air dispersion models and new/updated air standards;

• introduce air standards into the regulation with different averaging times (i.e. Ambient Air Quality Criteria or AAQCs) (see Appendices);

• deal with implementation barriers associated with timing, technology and/or economics using a risk-based decision making framework that includes public input; and

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http://www.ene.gov.on.ca/envision/techdocs/3614e02.pdf


• improve the clarity and enforceability of the regulation in order to better implement air standards and protect local air quality in Ontario.

Ontario's air standards are based on the best scientific information available and are set at levels that safeguard the natural environment and protect sensitive populations such as children and the elderly. Effects-based air standards are values that are based on health and environmental impacts without consideration of technology or economic issues. As outlined in the Standards Plan, MOE made a commitment to stakeholders to deal with technology and economic issues related to the updating of air quality standards through the development of a risk management framework.

2.0 Ontario’s Regulatory Framework

Compliance with air standards is intended to protect local communities from air pollution effects. The primary mechanism used to assess compliance with air quality standards has been the Certificate of Approval (Air) process (under Section 9 of the Ontario Environmental Protection Act). In order to build/expand their operations, industrial facilities with air emissions are required to obtain Certificates of Approval. With certain exceptions, a Certificate of Approval (C of A) is required for all new sources of air emissions or proposed alterations to existing sources(2). Modelling is used in the C of A process to assess the likelihood of compliance with Ontario’s air quality standards. Emission Summary and Dispersion Modelling (ESDM) reports provide valuable information that can be used to assess the likelihood of compliance with Ontario's air quality standards at a particular location. Air dispersion models can also be used for abatement or compliance assessment purposes. MOE's Selected Targets for Air Compliance (STAC) audits are aimed at assessing and enforcing compliance with air standards. Under STAC, MOE has been targeting a number of facilities in key sectors in order to assess compliance with the requirements of Regulation 346. In these audits, MOE requires industries to identify emission sources and assesses their emissions to determine compliance.

Models can also be used to predict impacts from accidental releases to the environment (i.e. fires, emergency bypasses, plant malfunctions, etc.) when ambient air monitors are not available to measure actual concentrations or when there is no technology available to measure a particular component in the ambient air. Finally, models can assist in determining where an ambient air monitor should be located.

2 For exemptions from the air approvals process, please refer to: Certificate of Approval Exemption (Air), O. Regulation 524/98 (as amended) and Ground Source Heat Pumps, O. Regulation 177/98.

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ESDM Reports can be used to assess the likelihood of impacts from a facility on the surrounding community. There are a number of reasons why MOE may request an emitter to undertake a compliance assessment of a particular facility. These include, but are not limited to: a known or anticipated impact from a facility's air emissions on the surrounding community; evidence or indications of an exceedance in ambient air quality standards that appear to be linked back to a facility; application for a C of A; selection of monitoring location, and/or the facility is a selected target of a compliance audit. An assessment for abatement or compliance purposes could be formally requested by a Provincial Officer or legally required by MOE through a legal instrument such as an Order or a C of A issued under the Environmental Protection Act.

2.1 Background – Previous Consultation In 1996, MOE published a plan to review and update, where necessary, provincial environmental standards. The plan was entitled: “Setting Environmental Quality Standards in Ontario - The Ministry of the Environment’s Standards Plan”. The purpose of the Standards Plan is to set priorities as well as to promote awareness in stakeholders about which standards would be updated or developed.

In 1997, the need for improved input and consultation with stakeholders was identified as a necessary and integral component of the standard setting process.

In March 1998, the first group of 14 air quality standards were posted to the Environmental Registry under the Environmental Bill of Rights (EBR). Subsequent stakeholder information sessions were held in the spring of 1998. Out of this consultation, four air quality guidelines were developed. The MOE now intends to adopt these guidelines as standards (see Appendices).

In September 1998, MOE hosted a stakeholder risk management workshop for air quality standards. A key outcome of the workshop was a recommendation by stakeholders that the MOE link initiatives, such as updating the air dispersion models, to the air standard setting process. MOE acknowledges that stakeholders’ views and comments on a proposed air standard may change if the existing Regulation 346 air dispersion models are replaced with the new models. The introduction of new models may affect the ability of industrial sources to comply with new or revised air quality standards. Implementation issues such as this can be dealt with under the proposed risk-based decision making process (see Section 5.0)

In 1999, MOE revised the Standards Plan: “Setting Environmental Quality Standards in Ontario - The Ministry of the Environment’s Standard Plan”. It also proposed to reaffirm 75 air quality guidelines and standards at their present values based on a comparative

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review of different jurisdictions. Decisions on these 75 air pollutants were posted on the EBR Environmental Registry in February 2000.

Also in February 2000, a second group of 18 air quality standards were developed and posted on the EBR Environmental Registry for comment. In some cases, air quality standards were finalized or reaffirmed at their existing levels. In other cases, reductions of one to two orders of magnitude were proposed in order to meet the final effects-based air quality standard developed in the risk assessment stage of the standard setting process. In cases where significant implementation issues were anticipated and/or there was a greater than 10 fold change in the standard, interim standards were proposed pending the outcome of MOE’s consultation on a risk management framework (see individual decision notices on the EBR Environmental Registry).

In March 2001, the MOE consulted on two discussion papers – one to introduce new air dispersion models and another to propose a risk management framework for air standards. Also in March 2001, MOE posted decisions on 18 air quality standards. Three stakeholder information sessions and focus groups were held during this consultation period. In September 2001, Regulation 346 was amended to reflect these decisions. The limits for eleven of these standards were identified as interim values pending the development of a framework to address time, technology and economic issues.

The MOE now proposes to phase-out the interim standards and adopt the final effects-based standards as described more fully in Section 3.0 below. It also proposes to deal with possible implementation issues as outlined in the proposed “Guideline for the Implementation of Air Standards in Ontario” (GIASO) (outlined in Section 5.0). Additional regulatory amendments are proposed that would permit the MOE to authorize a request that the standards set out in the Schedule(s) not apply to an existing facility for a limited period of time. A facility would have to apply to the MOE to have a different standard apply to it temporarily. However, the goal remains continual improvement towards compliance with the standards in the Schedules.

3.0 Ontario’s Air Standards

Ontario's air standards are based on the best scientific information available and are set at levels that safeguard the natural environment and protects sensitive populations such as children and the elderly. Setting air standards follows a multi-step process which incorporates key elements such as risk assessment and two stages of public consultation. This ensures that the full range of scientific issues and perspectives are considered when setting any new or revised air standard. Consultation is focused on development of the Ambient Air Quality Criteria (AAQC). This value is then converted

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to what has traditionally been a half hour POI concentration using an averaging time conversion factor (see ADMGO for details on conversion factors).

MOE proposes to promote the implementation of effects-based air standards. Effects-based air standards are values that are based on health and environmental impacts without consideration of technology or economic issues. Where barriers to implementation are identified, the proposal is to deal with them as outlined in the risk-based decision making process in the GIASO (see Section 5.0).

MOE is proposing to update Regulation 346 to reflect the consultation on air standards and/or guidelines conducted as part of the MOE Standards Plan. As such the following amendments to Regulation 346 in terms of air quality standards are now proposed. More detail is provided in the Appendices.

• Phase-out certain standards from Schedule 1 that were identified as interim during previous consultation.

• Introduce phase-in periods for new/updated air standards as needed (effective dates for implementation would be included in the Regulation). The phase-in period for new standards would normally be recommended as 5 years unless otherwise prescribed by regulation.

• One of the benefits of introducing new air dispersion models (see Section 4.0) is the ability to model for different averaging periods. MOE proposes to introduce a new schedule into Regulation 346 for air standards with effects-based averaging periods often referred to as the Ambient Air Quality Criteria (AAQC). The new schedule (“Schedule 2”) would contain screening values for POI standards (typically 1 hour) as well as AAQC standards (typically 10 min and/or 1 hour and/or 24 hour).

• Pending the phase-in of the new air dispersion models, MOE also proposes to introduce into Schedule 1, 1 hour POIs to match the outputs of the new models.

• MOE plans to include in the new Schedule 2 to the Regulation standards for the high priority contaminants that have undergone public consultation since the MOE Standards Plan was introduced.

• During the phase-in periods for new air dispersion models and for new/revised standards, the two Schedules of contaminants would co-exist. As MOE consults on new effects-based standards, they would be introduced into Schedule 2 with a phase-in period. Once new standards take effect, the standards for these contaminants in Schedule 1 will be phased-out.

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• It is proposed that Schedule 2 will eventually replace the current Schedule 1. A facility would be required to meet the standards in Schedule 2 upon the effective date when they become mandatory.

• A summary of the proposed amendments to Schedule 1 and the introduction of Schedule 2 are outlined in Appendix A. For details on each individual contaminant, please refer to the EBR Environmental Registry and the MOE’s Standards website: http://www.ene.gov.on.ca/envision/env_reg/er/documents/2001/airstandards/pa9e0002.htm

4.0 New Air Dispersion Models

The existing air dispersion models have been in place for over 30 years and do not reflect the latest scientific advancements in dispersion modelling. As a result, Regulation 346 models may underpredict maximal ground level concentrations of contaminants. Background information on the need for changes to the model was provided in the March 2001 Discussion Paper: “Updating Ontario’s Air Dispersion Models”. MOE received and considered extensive stakeholder comments on this document and is now proposing to move forward with adopting the new US EPA models into Ontario’s regulatory framework. MOE proposes to replace the existing models found in the Appendix to Regulation 346 with a suite of US EPA air dispersion models(3) (in particular AERMOD with PRIME hereafter referred to as AERMOD) which are referred to as the “new models” for Ontario. The new models include more recent science than was available in the development of Regulation 346 models and have more realistic treatments for several of the processes that affect dispersion. Hence, the new air dispersion models are better assessment tools for predicting maximum ground level or POI concentrations of contaminants. They consider all atmospheric stabilities (i.e. stable, neutral and unstable) and can also incorporate actual or representative meteorological data into the model. Atmospheric and/or meteorological conditions can significantly affect plume behaviour and the predicted concentration of a contaminant.

3 The US EPA Notice of Proposed Changes to the suite of air dispersion models can be found at www.epa.gov/ttn/scram/. Part 51, Chapter 1, title 40 of the Code of the Federal Regulations (CFR), Appendix W to Part 51 - - GUIDELINE ON AIR QUALITY MODELS, includes Appendix A – Summary of Preferred/Recommended Models.

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http://www.ene.gov.on.ca/envision/env_reg/er/documents/2001/airstandards/pa9e0002.htm

http://www.epa.gov/ttn/scram/


In order to adopt the new models, MOE proposes to amend Regulation 346 so that:

• after a phase-in period of time (proposed to be three years commencing from the time the Regulation is amended), the Regulation 346 models that appear in the Appendix would be phased-out; and

• the new models are incorporated into Regulation 346 by reference to the US EPA models; and

• the regulation would allow for adoption of future changes to these existing US EPA models. In accordance with section 177(6) of the Environmental Protection Act, each time that the US EPA amends its models, MOE may provide a notice of an amendment to Ontario models on the EBR Environmental Registry and/or in the Ontario Gazette. Consultation on any new models would always be a requirement under EBR; and

• the regulation would also provide authority to the MOE to compel the use of alternate models and/or methods to determine compliance with air standards and allow for proponents to use other alternative models and/or methods to determine compliance with air standards, if considered acceptable by the MOE.

For further information on the technical aspects of using these models, please refer to the proposed “Air Dispersion Modelling Guideline for Ontario” (ADMGO), June 2004.

4.1 Introducing effects-based averaging times A key advantage to introducing the new air dispersion models is the ability to assess compliance with air standards with variable averaging periods (i.e. AAQCs). The new models can calculate concentrations from 1 hour up to 1 year. A contaminant could be assessed using modelled exposure concentrations over the most appropriate averaging period for that contaminant. For example, the effects-based averaging time for health-based air standards is typically 24 hours (or daily); the effects-based averaging time for odour-based compounds is normally considered to be 10 minutes. This provides a more representative assessment of health and environmental impacts from air emissions.

MOE proposes to introduce effects-based standards with appropriate averaging times into Regulation 346 as regulatory standards. The proposal is to include, where they are known, all effects-based standards with appropriate averaging times for contaminants (AAQCs). For example, if a contaminant has both a 10 minute odour-based AAQC as well as a 24 hour health-based AAQC, both would be included in the regulation and

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compliance with both must be demonstrated. Proposed revisions to Schedule 1 and the new Schedule 2 of Regulation 346 are included in the Appendices for comment.

The proposed Schedule 2 includes a phase-in period (effective date) for new or revised air quality standards. Facility operators would be provided with the option of assessing compliance with a screening level POI for air quality standard (1 hour POI) or with the effects-based standard(s) with the appropriate averaging time (AAQC) using the more refined air dispersion models. This tiered approach is outlined in the ADMGO.

In order to ensure compliance with air standards, as set out in section 5 of Regulation 346, and introduce effects-based standards with variable averaging times, the MOE proposes to amend the regulation to:

• add a new schedule (“Schedule 2”) of contaminants that reflects AAQC standards for a range of averaging times, specifically 10 min, 1 hour, 24 hour and any other period considered appropriate for the contaminant, as well as a 1 hour screening POI standard; and

• stipulate that compliance with the 1 hour screening standard is required unless more refined dispersion models are used to assess compliance with the standards with variable averaging periods (AAQC); and

• where there is more than one AAQC for a contaminant, such as a 10 minute standard for odour and a 24 hour standard that is health-based, then compliance with both must be demonstrated. Compliance with the AAQC will take precedence over the 1 hour POI screening level; and

• after the new models take effect, a facility would be required to meet the limits that are in force in Schedule 2. However, until a new standard in the new Schedule becomes effective, a facility will be held to the 1 hour POI concentrations in amended Schedule 1, unless the facility can demonstrate that it meets the AAQC(s) in Schedule 2. If there are no AAQCs in Schedule 2 and no 1 hour POIs in the amended Schedule 1(4), MOE would specify how to adapt the

4 MOE plans to review odour, corrosion and particulate based standards to ensure they are up to date and/or appropriate for use with the new models. MOE will also assess its strategy for dealing with odour issues (see ADMGO). Further regulatory revisions may be considered to reflect these decisions and clarify how standards with averaging times less than 1 hour would be calculated/assessed for compliance.

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new models to determine compliance with ½ hour POIs (i.e. the only compliance point available).

• Any new facility submitting an application for a C of A must use the new models to demonstrate compliance with the standards in the Schedule 2. If there is no value for a contaminant in Schedule 2, the facility must comply with the appropriate value in Schedule 1.

4.2 Implementation issues with new models The formal adoption of the new air dispersion models into Ontario could mean a change in the compliance status of some facilities. A facility may be in compliance using the Regulation 346 models yet, without having made any physical or raw material changes to its processes, not be in compliance with the air quality standards using the new models. Dealing with such differences in predicted concentrations is one of the reasons why the phase-in period to introduce the new models is so important. Industrial stakeholders will need time to assess their overall plant emissions using these new models and address compliance issues where necessary. It will also take time for users of the new air dispersion models to acquire and familiarize themselves with the models. MOE has been discussing the proposal to adopt these models since before 2001. Many consultants and some industries are likely familiar with the new models.

MOE proposes to phase-in the use of the new models. The proposed phase-in period will be three years commencing from the time the Regulation 346 is amended. During the phase-in period, a facility would be able to choose whether to use the Regulation 346(5) models in the Appendix to meet ½ hour POI standards in Schedule 1, or use the new models to meet 1 hour POI standards in Schedule 1. Alternatively, compliance with the effects-based standards (AAQC) in Schedule 2 would also be accepted in the interim period. Upon promulgation of the Regulation, companies submitting new C of A applications for new facilities would be required to demonstrate compliance with all the standards in the Schedule 2 using the new models.

A facility identifying significant implementation issues with the change to the new models prior to the end of the phase-in period may be eligible to enter into a risk-based decision making process, outlined in the document entitled “Guideline for Implementation of Air Standards in Ontario” (GIASO) (see Section 5.0).

5 For Certificate of Approval applications where odour is an issue, the Environmental Assessment and Approvals Branch (EAAB) requires proponents to use a model that considers all dispersion conditions. Hence, for odour impact assessments, the US EPA models will continue to be used (see ADMGO).

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4.3 Proposal to update Emission Estimation Methodology Emission estimates are key modeling inputs. As noted, MOE proposes to adopt the use of effects-based standards, and require more advanced dispersion models that allow for different averaging periods to be used. As such, the methodology of estimating emissions should be similarly updated. With the existing Regulation 346 models, assessment of a facility is done using the maximum ½ hour emission rate and comparing that to a “screening level” concentration typically referred to as the maximum ground level concentration. If a facility meets the screening level or maximum ½ hour concentration, then it is likely to meet the AAQC. With the new models, the ½ hour averaging period would be replaced by a 1 hour averaging period (see Appendices). The proposed new air dispersion models mean that proponents are not restricted to modelling for the 1 hour worst case scenario but can actually assess concentrations using the most appropriate averaging time emission rate for that contaminant.

For example, for facilities where emissions occur for only part of the day or vary significantly during the day, emission rates for the actual operating times could be used in assessing compliance with the most appropriate effects-based air quality standard (e.g. a 24 hour health-based). Annual average emissions rates must not be used as modeling inputs. For 10 minute averaging periods for odour-based AAQCs, facilities should model for a worst case 10 minute emission rate and then convert the one hour output to a 10 minute averaging time using the appropriate conversion factors (see section 3.5 of the ADMGO).

Facilities are responsible for supporting their maximum emission rate scenario based on their specific operations – averaging emissions over long periods of time (e.g. annual) is not acceptable.

Emission rates are key model input parameters and their variations and quality are proportional to variations in the model output. MOE proposes to update and revise its current guidance material associated with estimating emissions and developing Emission Summary and Dispersion Modelling (ESDM) reports(6). As a minimum, work towards providing better guidance on the development of realistic emission scenarios, particularly in situations where emission rates are variable, is needed. Consideration

6 Guidance for preparation of an ESDM is available in the document entitled "Procedure for Preparing an Emission Summary and Dispersion Modelling Report" and dated June 1998, as amended from time to time (referenced in O. Reg. 363/98 – Fees –Certificates of Approval). Additional guidance material for STAC could also be considered.

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would be given to better outlining the distinctions between assessments required for the C of A process and for compliance auditing purposes.

5.0 A Proposed Guideline for the Implementation of Air Standards in Ontario

As part of the implementation of the 1999 Standards Plan, MOE made a commitment to stakeholders to deal with technology and economic issues related to the updating of air quality standards. The proposed “Guideline for the Implementation of Air Standards in Ontario” (GIASO) would combine effects-based standards that protect communities with a risk-based decision making process that allows for a case-by-case assessment of implementation issues, where technological, timing or economic barriers are identified. Effects-based standards are values that are based on health and environmental impacts – not technology or economics considerations.

The proposed risk-based decision making process outlined in GIASO is broader than the proposal outlined in the 2001 discussion paper: “A Proposed Risk Management Framework for the Air Standard Setting Process in Ontario”. It allows for consideration not only of timing, technology and economic factors, but also outlines a process for risk ranking. It encourages public transparency in decision making, and a cycle of continuous improvement to review interim solutions in the implementation of new air standards as well as new air dispersion models. The proposed risk-based decision making process contemplates the use of options, incentives and enhanced enforcement to promote earlier and effective implementation of air standards while providing flexibility, consistency and equity amongst the regulated community.

The concepts set out in GIASO are based on the lessons learned from a pilot project with five industrial facilities, an environmental non-government organization and MOE. This pilot project was initiated in July 2003 and is currently in its final stages.

MOE recognizes that the introduction of new or revised air standards and models means that not all facilities may be able to achieve compliance with MOE air standards immediately due to technology limitations and economic realities. There may be a need for more time to assess, plan and if necessary, finance and install new equipment or processes to reduce ground level concentrations (GLCs) and/or emissions. For some facilities, a reasonable phase-in period for new models and/or new/revised air standards would provide enough time to assess, plan, budget and implement technical solutions to ensure compliance with the air standards. Other facilities might not be able to achieve compliance with the air standard within the proposed phase-in period due to technical

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and/or economic considerations. The phase-in period for new standards would normally be recommended as 5 years unless otherwise prescribed by regulation.

If a company were able to demonstrate that compliance with an air standard(s) could not be achieved during the phase-in period, then the risk-based decision making process outlined in this GIASO could be considered.

The facility would be required to identify implementation barriers for the new/revised standards or new models within a timeframe specified by the regulation. If potential compliance issues are identified, the company would make application to the MOE for the standard not to apply to that facility for a specified period of time (i.e. for a different standard to apply to it temporarily) (7). It is proposed that the prescribed deadline to apply would be one year after the date the regulation is amended to introduce a new standard or new models. This would be well before the date the standard or model becomes effective. If an application was not submitted within the prescribed period, and a compliance issue (i.e. non-compliance related to new standards and/or new models) was subsequently identified after the phase-in period, then the facility would be subject to possible abatement and enforcement measures as outlined in the MOE’s Compliance Guideline F-2 (as amended).

By way of this application, which would have to be supplemented by sufficient supporting documentation/proof and an action plan, the MOE would assess whether temporary variation from the proposed standard would be provided and under what conditions. There may be instances, as outlined in GIASO, where the MOE would not permit a different standard to apply to a facility, even on a temporary basis. For example, there is an expectation that if the amount by which a contaminant is above the standard exceeds a prescribed risk threshold, then some minimum level of risk reduction must be implemented in order for that facility to continue operation at its current production level. For carcinogens, this is a 1 in 10,000 risk level; for non-carcinogens, is it is 10 times the effects-based standard. This would consider the frequency of occurrence which should be <16% of the time based on modeling information at the maximum GLC.

In order to implement these provisions, Regulation 346 would be amended to reflect the following:

7 These requirements would be modelled after section 38 of the Safe Drinking Water Act (SDWA).

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• Additional regulatory amendments are proposed that would permit the MOE to authorize a request that the standards set out in the Schedule(s) not apply to an existing facility for a limited period of time, if the facility could not meet a new standard or if the facility was using a new model and could not meet an existing standard.

• Whenever the Regulation is amended to impose a new or revised standard or a new model, any facility wanting a different standard to apply to it temporarily would be required by the Regulation to apply to the MOE within one year following the date the Regulation is amended. This will ensure that companies are using the phase-in period as it was intended – to plan and implement required changes with the goal of eventually complying with the prescribed standard.

• In addition to the above, MOE would have the authority to impose a less onerous condition or requirement in a Section 9 C of A, such as allowing an interim limit based on site, sector or technology considerations. The imposition of reporting requirements to monitor progress toward meeting the regulatory standards would also be considered. The proposed period of review would be up to 10 years but could vary depending on the facility and the contaminants (see Section 2.8 of GIASO).

• As part of the written application to have a different standard apply temporarily to that facility, the following information would prepared by a professional engineer, registered in the Province of Ontario, and would have to be submitted:

o a valid ESDM report that considers both absolute (“worst case”) maximum and reasonable maximum emission scenarios;

o a technology benchmarking review that identified all best available solutions to reduce ground level concentrations (Section 2.4 of GIASO);

o considerations with respect to the period of time required to implement changes as well as technological and economic issues (Section 2.5 of GIASO);

o the need for public consultation (Section 2.6 of GIASO); and

o other considerations.

• The regulation would also specify that this type of approval would be time limited, as determined by the MOE, but that the person would be permitted to apply before the expiration period for an extension. The intent is to build in a cycle of continual improvement that will promote an updated review of technologies with a goal towards achieving the effects-based standard.

April 2004 page 18


• Notice of the aforementioned application to MOE would be posted on the Environmental Bill of Rights (EBR) Registry. As such, the regulation under the EBR (Regulation 681/94 – Classification of Proposals for Instruments) would be amended to clarify that such applications are classified as proposals.

• The regulation could also outline factors to consider in denying a facility’s application to substitute a different standard for the contaminant(s) in question.

• As noted above, MOE would require a submission that identified the best available technological solutions that would reduce ground level concentrations of contaminants. This “technology benchmarking assessment” (or assessment of best available technology) would have to demonstrate that the facility was making all reasonable efforts to reduce ground level concentrations before the MOE would consider approving a different standard from that standard prescribed in the Regulation. This technology benchmarking may be subject to a third party review. The third party will make recommendations to the MOE for final decision. All applications will likely require the submission of a fee commensurate with the level of review.

Facilities that apply for consideration based on economic hardship must submit sufficient information in order for that decision to be evaluated. Guideline F-14 - Economic Analyses of Control Documents on Private Sector and Municipal Projects would be considered. Economic analysis of information may also be subject to a third party review.

5.1 More Effective Implementation of Regulation 346 Clearer and more enforceable provisions in Regulation 346 are key to better implementation of the air compliance program and subsequent adherence to air standards.

To enhance the implementation of this Regulation and allow for the MOE to better assess compliance with standards when new standards are introduced and new models take effect, a new provision is proposed. It is proposed that Regulation 346 be amended to compel air emitters subject to Regulation 346 to prepare and maintain an ESDM report, to update it under prescribed circumstances and to submit this report to the MOE upon request. These reports are a means of assessing whether the facility is in compliance with the air standards. Consideration is being given to providing exemptions from this provision, potentially on either a broad or a more limited case-by-case basis. It is proposed that this provision would be phased-in to coincide with the phase-in period for air dispersion models, which is proposed as three years, commencing from the time the Regulation is amended. To meet this requirement,

April 2004 page 19


facilities would be required to employ new models in their ESDM report compliance assessment.

It is also proposed that the Regulation be amended to clarify the type of assessment required for an ESDM report to be kept under this new provision. Distinctions between the assessment required for the C of A process and for compliance auditing purposes would be outlined, as would requirements to retain results from these reports on site.

Regulation 346 (section 5) compels adherence to standards and prescribes the use of models in the assessments. MOE proposes that the Regulation be amended as set out above to reflect these new initiatives. Existing definitions in the Regulation may also be reworded or new definitions inserted to improve clarity and enforceability.

It is also proposed that the Regulation stipulate that where emissions are from more than one source, the contaminant concentrations at the POI resulting from each individual source would be added together to give an aggregate value for the concentration. This aspect of the regulation exists in the Appendix to the existing regulation and would be maintained in any revised regulation.

6.0 Other regulatory amendments

The visible emissions provisions of Regulation 346 require updating. Portions of sections 7 and 8 of the Regulation and related definitions would be amended to reflect current MOE practices. Training of provincial officers for the assessment of visible emissions is currently based on the principles of US EPA Section 3.12 Method 9 – Visible Determination of Opacity of Emissions from Stationary Sources. The MOE proposes to review existing provisions and methods for determining the opacity of visible emissions and amend the regulation as needed, to better reflect actual training practices and methodologies.

April 2004 page 20


7.0 Consistency

A variety of communications tools may be helpful to ensure consistent application of the models either through the approvals process or when dealing with abatement issues. These tools may include, but are not limited to, partnerships with various associations and service providers to train industrial stakeholders, ENGOs, and MOE staff; establishing a web site; publication of technical bulletins related to modelling issues; and ongoing dialogue with MOE to strive for a consistent application of the tools.

The results of public consultation on these proposals will influence any amendments to Regulation 346. They will also be used to finalize the proposed MOE “Air Dispersion Modelling Guide for Ontario” (ADMGO), the proposed “Guideline for the Implementation of Air Standards in Ontario” (GIASO) and the proposed development of revised guidance material on estimating emissions.

The comment period for this position paper is 120 days from the date it is posted on the EBR Environmental Registry.

April 2004 page 21


Appendix A: Proposed Revisions - Reg 346 Schedule 1

Schedule 1 No. CAS No. Contaminant Name ½-Hour POI

Limit (µg/m³) 1-Hour POI

Limit (µg/m³) Basis Status

1 64-19-7 Acetic Acid 2500 - Odour S

2 67-64-1 Acetone Note (i) 48000 - Odour S

3 74-86-2 Acetylene 56000 - Odour S

4 79-06-1 Acrylamide 45 37.5 Health S

5 107-13-1 Acrylonitrile 180 150 Interim S

6 7664-41-7 Ammonia 3600 - Odour S

7 7440-36-0 Antimony 75 62.5 Health S

8 7784-42-1 Arsine 10 8.3 Health S

9 7440-41-7 Beryllium and compounds 0.03 0.025 Health S

10 7440-42-8 Boron 100 100 Particulate S

11 10294-33-4 Boron Tribromide 100 100 Corrosion S

12 10294-34-5 Boron Trichloride 100 100 Corrosion S

13 7637-07-2 Boron Trifluoride 5 5 Vegetation S

14 7726-95-6 Bromine 70 50 Health S

15 7440-43-9 Cadmium 5 5 Health S

16 1305-62-0 Calcium hydroxide 27 27 Corrosion S

17 1305-78-8 Calcium oxide 20 20 Corrosion S

18 1333-86-4 Carbon Black 25 25 Soiling S

19 75-15-0 Carbon Disulphide 330 - Odour S

20 630-08-0 Carbon monoxide 6000 5000 Health S

21 7782-50-5 Chlorine 300 250 Health S

22 10049-04-4 Chlorine Dioxide 85 75 Health S

23 67-66-3 Chloroform 300 250 Interim S

24 7440-50-8 Copper 100 83 Health S

25 1319-77-3 Cresols 230 187.5 Health S

26 17702-41-9 Decaborane 50 50 Health S

27 19287-45-7 Diborane 20 20 Health S

28 131-15-7 Dicapryl Phthalate 100 100 Particulate S

29 624-92-0 Dimethyl Disulphide 40 - Odour S

30 75-18-3 Dimethyl Sulphide 30 - Odour S

31 117-84-0 Di-n-octyl phthalate 100 100 Particulate S

32 N/A Dustfall 8000 µg/m² - Soiling S

33 141-78-6 Ethyl acetate 19000 - Odour S

April 2004 page 22


No. CAS No. Contaminant Name ½-Hour POI Limit (µg/m³)

1-Hour POI Limit (µg/m³) Basis Status

34 140-88-5 Ethyl acrylate 4.5 - Odour S

35 100-41-4 Ethyl Benzene 3000 2500 Interim S

36 60-29-7 Ethyl Ether 7000 5833 Interim S

37 1309-37-1 Ferric oxide 75 75 Soiling S

38 7664-39-3 Fluorides (as HF) - Gaseous (Growing Season) 4.3 4.3 Vegetation S

39 7664-39-3 Fluorides (as HF) - Total (Apr15 to Oct15) 8.6 8.6 Vegetation S

40 7664-39-3 Fluorides (as HF) - Total (Oct.16 to Apr.14) 17.2 17.2 Vegetation S

41 50-00-0 Formaldehyde 65 - Odour S

42 64-18-6 Formic Acid 1500 1250 Health S

43 98-01-1 Furfural 1000 - Odour S

44 98-00-0 Furfuryl Alcohol 3000 2500 Health S

45 7647-01-0 Hydrogen Chloride 100 100 Corrosion S

46 74-90-8 Hydrogen Cyanide Note (i) 1150 958 Health S

47 7783-06-4 Hydrogen Sulphide 30 - Odour S

48 15438-31-0 Iron (metallic) 10 10 Soiling S

49 98-82-8 Isopropyl Benzene 100 - Odour S

50 7439-92-1 Lead 6 5 Health S

51 7439-93-2 Lithium 60 50 Health S

52 7580-67-8 Lithium Hydrides 7.5 6.3 Health S

53 1309-48-4 Magnesium oxide 100 100 Particulate S

54 74-93-1 Mercaptans 20 - Odour S

55 7439-97-6 Mercury 5 5 Health S

56 N/A Mercury (alkyl) 1.5 1.25 Health S

57 67-56-1 Methanol (Methyl Alcohol) 12000 10000 Health S

58 96-33-3 Methyl Acrylate 4 - Odour S

59 71-55-6 Methyl Chloroform Note (ii) 350000 287500 Health S

60 78-93-3 Methyl Ethyl Ketone 30000 25000 Interim S

61 108-10-1 Methyl Isobutyl Ketone 1200 - Odour S

62 80-62-6 Methyl methacrylate 860 - Odour S

63 N/A Milk Powder 20 20 Soiling S

64 8052-41-3 Mineral Spirits Note (iii) 7800 6500 Health S

65 74-89-5 Monomethyl Amine 25 - Odour S

66 142-82-5 n-Heptane 33000 27500 Health S

67 7440-02-0 Nickel 5 5 Vegetation S

68 13463-39-3 Nickel Carbonyl 1.5 1.25 Health S

69 7697-37-2 Nitric acid 100 100 Corrosion S

70 139-13-9 Nitrilotriacetic Acid 100 100 Health S

71 10102-44-0 Nitrogen Oxides 500 400 Health S

April 2004 page 23


No. CAS No. Contaminant Name ½-Hour POI Limit (µg/m³)

1-Hour POI Limit (µg/m³) Basis Status

72 10028-15-6 Ozone 200 165 Health S

73 19624-22-7 Pentaborane 3 2.5 Health S

74 108-95-2 Phenol Note (i) 100 83 Health S

75 75-44-5 Phosgene 130 112.5 Health S

76 7664-38-2 Phosphoric Acids 100 100 Particulate S

77 85-44-9 Phthalic Anhydride 100 100 Particulate S

78 78-87-5 Propylene Dichloride 2400 - Odour S

79 75-56-9 Propylene Oxide 450 375 Interim S

80 7440-22-4 Silver 3 2.5 Health S

81 100-42-5 Styrene 400 - Health S

82 7446-09-5 Sulphur Dioxide 830 690 Health S

83 7664-93-9 Sulphuric Acid 100 100 Corrosion S

84 N/A Suspended Particulate Matter (< 44 µm Diameter) 100 100 Visibility S

85 13494-80-9 Tellurium (except hydrogen telluride) 30 25 Health S

86 109-99-9 Tetrahydrofuran 93000 - Odour S

87 7440-31-5 Tin 30 25 Health S

88 7440-32-6 Titanium 100 100 Particulate S

89 108-88-3 Toluene 2000 - Odour S

90 584-84-9 Toluene Di-isocyanate, 2,4- Note (i) 1 0.83 Health S

91 79-01-6 Trichloroethylene (TCE) Note (i) 3500 2875 Interim S

92 76-13-1 Trifluorotrichloro Ethane Note (ii) 2400000 2000000 Health S

93 7440-62-2 Vanadium 5 5 Health S

94 75-35-4 Vinylidene Chloride 30 25 Health S

95 1330-20-7 Xylenes Note (i) 2300 - Odour S

96 7440-66-6 Zinc 100 100 Particulate S Notes:

Note (i) Standard currently being updated through the MOE’s standard consultation process. Note (ii) CFC Class 1 Listed – (Refer to Part VI of the Ontario Environmental Protection Act R.S.O. 1990, C. E-19 and the

applicable Regulations made under the Act, on the manufacture, use, storage, disposal, etc., of these ozone depleting substances.

Note (iii) Mineral spirits are petroleum distillate mixtures of C7-C12 hydrocarbons, with boiling points ranging from 130-220 °C and flash points ranging from 21-60 °C. Please see Rationale document: “Ontario Air Standards for Mineral Spirits” for further detail.

S Air Quality Standard

G Air Quality Guideline

April 2004 page 24


Appendix B: Proposed Revisions - Reg 346 Schedule 2

Schedule 2 Point of Impingement (POI) Concentration Ambient Air Quality Criteria (AAQC)

No. CAS No. Contaminant Name POI Limit (µg/m³)

Averaging Period Basis Status 24-Hour

(µg/m³) 1-Hour (µg/m³)

10-Min (µg/m³)

Other Period (µg/m³)

Limiting Effect

Effective Date

1 N/A 2,4-toluene diisocyanate & 2,6-toluene diisocyanate [584-84-9; 91-08-7] (mixed isomers)

0.5 1 hr Health S 0.2 Health 5 years

Note(a)

2 75-07-0 Acetaldehyde 500 ½ hr Irritation Note(c) S 500 Health Note (b)

3 67-64-1 Acetone 29700 1 hr Health S Note(g) 11880 Health 5 years

Note(a)

4 75-05-8 Acetonitrile 175 1 hr Health G Note(g) 70 Health 5 years

Note(a)

5 107-02-8 Acrolein 0.2 1 hr Health S Note(g) 0.08 Health 5 years Note(a)

6 79-06-1 Acrylamide 37.5 1 hr Health S 15 Health Note (b)

7 107-13-1 Acrylonitrile 1.5 1 hr Health S 0.6 Health 3 years

Note(a)

8 7664-41-7 Ammonia 250 1 hr Health S 100 Health 3 years

Note(a)

9 7440-36-0 Antimony 62.5 1 hr Health S 25 Health Note(b)

10 7784-42-1 Arsine 8.3 1 hr Health S 5 Health Note(b)

11 7440-41-7 Beryllium and compounds 0.025 1 hr Health S 0.01 Health Note(b)

12 7440-42-8 Boron 100 1 hr Particulate Note(c) S 120 Particulate Note(b)

13 10294-33-4 Boron Tribromide 100 1 hr Corrosion Note(c) S 35 Corrosion Note(b)

14 10294-34-5 Boron Trichloride 100 1 hr Corrosion Note(c) S 35 Corrosion Note(b)

15 7637-07-2 Boron Trifluoride 5 1 hr Vegetation Note(c) S 2 Vegetation Note(b)

16 7726-95-6 Bromine 50 1 hr Health S 20 Health Note(b)

17 7440-43-9 Cadmium 5 1 hr Health S 2 Health Note(b)

18 1305-62-0 Calcium hydroxide 27 1 hr Corrosion Note(c) S 13.5 Corrosion Note(b)

April 2004 page 25


Point of Impingement (POI) Concentration Ambient Air Quality Criteria (AAQC) No. CAS No. Contaminant Name POI Limit

(µg/m³) Averaging

Period Basis Status 24-Hour (µg/m³)

1-Hour (µg/m³)

10-Min (µg/m³)


Limiting Effect

Effective Date

19 1305-78-8 Calcium oxide 20 1 hr Corrosion Note(c) S 10 Corrosion Note(b)

20 1333-86-4 Carbon Black 25 1 hr Soiling Note(c) S 10 Soiling Note(b)

21 630-08-0 Carbon monoxide 5000 1 hr Health Note(c) S 36200 15700 (8hr) Health Note(b)

22 56-23-5 Carbon Tetrachloride 6 1 hr Health S 2.4 Health Note(b)

23 7782-50-5 Chlorine 25 1hr Health S 10 3 years

Note(a)

24 10049-04-4 Chlorine Dioxide 75 1 hr Health S 30 Health Note(b)

25 67-66-3 Chloroform 2.5 1 hr Health S 1 Health 3 years

Note(a)

26 7440-50-8 Copper 100 1 hr Health S 50 Health; Particulate Note(b)

27 1319-77-3 Cresols 187.5 1 hr Health S 75 Health Note(b)

28 110-82-7 Cyclohexane 15250 1 hr Health G Note(g) 6100 Health 5 years

Note(a)

29 17702-41-9 Decaborane 50 1 hr Health S 25 Health Note(b)

30 117-81-7 Di(2-ethylhexyl) phthalate 100 1hr Health/ Particulate Note(c) G Note(g) 50 Health Note(b)

31 19287-45-7 Diborane 20 1 hr Health S 10 Health; Particulate Note(b)

32 131-15-7 Dicapryl Phthalate 100 1 hr Particulate Note(c) S 120 Particulate Note(b)

33 106-46-7 Dichlorobenzene, 1,4- 237.5 1 hr Health G 95 Health Note(b)

34 117-84-0 Di-n-octyl phthalate 100 1 hr Particulate Note(c) S Note(g) 120 Particulate Note(b)

35 N/A Dustfall 8000 µg/m² 1 hr Soiling Note(c) S 7g/m² (30day) Note(b)

36 100-41-4 Ethyl Benzene Note (e) Odour S 1000 1900 Health; Odour

3 years

Note(a)

37 60-29-7 Ethyl Ether Note (e) Odour S 8000 950 Health; Odour

3 years

Note(a)

38 107-06-2 Ethylene Dichloride 5 1 hr Health G 2 Health Note(b)

39 1309-37-1 Ferric oxide 75 1 hr Soiling Note(c) S 25 Soiling Note(b)

40 7664-39-3 Fluorides (as HF) - Gaseous (Growing Season) 4.3 1 hr Vegetation Note(c) S Note(g) 0.86 0.34

(30 day) Vegetation Note(b)

41 7664-39-3 Fluorides (as HF) - Total (Apr15 to Oct15) 8.6 1 hr Vegetation Note(c) S Note(g) 1.72 0.69


April 2004 page 26



(µg/m³) Averaging


1-Hour (µg/m³)

10-Min (µg/m³)


Limiting Effect

Effective Date

42 7664-39-3 Fluorides (as HF) - Total (Oct.16 to Apr.14) 17.2 1 hr Vegetation Note(c) S Note(g) 3.44 1.38


43 50-00-0 Formaldehyde 65 ½ hr Odour Note(d) S 65 Health Note(b)

44 64-18-6 Formic Acid 1250 1 hr Health S 500 Health Note(b)

45 98-00-0 Furfuryl Alcohol 2500 1 hr Health S 1000 Health Note(b)

46 4035-89-6 HDI Biuret (HDI-BT) 2.5 1 hr Health S Note(g) 1 Health Note(b)

47 3779-63-3 HDI Isocyanurate (HDI-IC) 2.5 1 hr Health S Note(g) 1 Health 5 years

Note(a)

48 28182-81-2 HDI Polyisocyanate (HDI-BT & HDI-IC) 2.5 1 hr Health S Note(g) 1 Health 5 years

Note(a)

49 822-06-0 Hexamethylene Diisocyanate (HDI) Monomer 0.075 1 hr Health S Note(g) 0.03 Health 5 years

Note(a)

50 7647-01-0 Hydrogen Chloride 50 1 hr Health S 20 Health 3 years

Note(a)

51 74-90-8 Hydrogen Cyanide 20 1 hr Health S Note(g) 8 Health 5 years

Note(a)

52 15438-31-0 Iron (metallic) 10 1 hr Soiling Note(c) S 4 Soiling Note(b)

53 67-63-0 Isopropanol (Isopropyl alcohol) 18250 1 hr Health G Note(g) 7300 Health 5 years

Note(a)

54 98-82-8 Isopropyl Benzene 100 ½ hr Odour S 400 Health Note(b)

55 7439-92-1 Lead 5 1 hr Health S 2 Health Note(b)

56 7439-93-2 Lithium 50 1 hr Health S 20 Health Note(b)

57 7580-67-8 Lithium Hydrides 6.3 1 hr Health S 2.5 Health Note(b)

58 1309-48-4 Magnesium oxide 100 1 hr Particulate Note(c) S 120 Particulate Note(b)

59 7439-97-6 Mercury 5 1 hr Health S 2 Health Note(b)

60 N/A Mercury (alkyl) 1.25 1 hr Health S 0.5 Health Note(b)

61 101-68-8 Methane Diphenyl Diisocyanate (MDI Monomer) 1.75 1 hr Health S Note(g) 0.7 Health 5 years

Note(a)

62 67-56-1 Methanol (Methyl Alcohol) 10000 1 hr Health S 4000 Health Note(b)

63 71-55-6 Methyl Chloroform 287500 1 hr Health S Note(f) 115000 Health Note(b)

64 78-93-3 Methyl Ethyl Ketone 2500 1 hr Health S 1000 Health 3 years

Note(a)

April 2004 page 27



(µg/m³) Averaging


1-Hour (µg/m³)

10-Min (µg/m³)


Limiting Effect

Effective Date

65 624-83-9 Methyl Isocyanate 2.5 1 hr Health G Note(g) 1 Health 5 years

Note(a)

66 75-09-2 Methylene Chloride (Dichloromethane) 550 1 hr Health G Note(g) 220 Health 3 years

Note(a)

67 N/A Milk Powder 20 1 hr Soiling Note(c) S 20 Soiling; Odour Note(b)

68 8052-41-3 Mineral Spirits 3000 ½ hr Odour Note(d) S 2600 Health 3 years

Note(a)

69 142-82-5 n-Heptane 27500 1 hr Health S 11000 Health Note(b)

70 110-54-3 n-Hexane 6250 1 hr Health S 2500 5 years

Note(a)

71 7440-02-0 Nickel 5 1 hr Vegetation Note(c) S 2 Vegetation Note(b)

72 13463-39-3 Nickel Carbonyl 1.25 1 hr Health S 0.5 Health Note(b)

73 7697-37-2 Nitric acid 100 1 hr Corrosion Note(c) S 35 Corrosion Note(b)

74 139-13-9 Nitrilotriacetic Acid 100 1 hr Health; Particulate Note(c) S 120 Particulate Note(b)

75 10102-44-0 Nitrogen Oxides 400 1 hr Health S 200 400 Health Note(b)

76 10028-15-6 Ozone 165 1 hr Health S 165 Health; Vegetation Note(b)

77 19624-22-7 Pentaborane 2.5 1 hr Health S 1 Health Note(b)

78 127-18-4 Perchloroethylene (PERC) 900 1 hr Health S Note(g) 360 Health 3 years

Note(a)

79 108-95-2 Phenol 75 1 hr Health S Note(g) 30 Health 5 years

Note(a)

80 75-44-5 Phosgene 112.5 1 hr Health S 45 Health Note(b)

81 7664-38-2 Phosphoric Acid 100 1 hr Particulate Note(c) S 120 Particulate Note(b)

82 85-44-9 Phthalic Anhydride 100 1 hr Particulate Note(c) S 120 Particulate Note(b)

83 9016-87-9 Polymeric Methane Diphenyl Diisocyanate (MDI Polymer) 1.75 1 hr Health S Note(g) 0.7 Health 5 years

Note(a)

84 75-56-9 Propylene Oxide 3.75 1 hr Health S 1.5 3 years

Note(a)

85 7440-22-4 Silver 2.5 1 hr Health S 1 Health Note(b)

86 100-42-5 Styrene 400 ½ hr Health; Odour S 400 Health Note(b)

87 7446-09-5 Sulphur Dioxide 690 1 hr Health S 275 690 Health; Vegetation Note(b)

April 2004 page 28


April 2004 page 29


(µg/m³) Averaging


1-Hour (µg/m³)

10-Min (µg/m³)


Limiting Effect

Effective Date

88 7664-93-9 Sulphuric Acid 100 1 hr Corrosion Note(c) S 35 Corrosion Note(b)

89 N/A Suspended Particulate Matter (< 44 µm Diameter) 100 1 hr Visibility S 120 Visibility Note(b)

90 13494-80-9 Tellurium (except hydrogen telluride) 25 1 hr Health S 10 Health Note(b)

91 7440-31-5 Tin 25 1 hr Health S 10 Health Note(b)

92 7440-32-6 Titanium 100 1 hr Particulate Note(c) S 120 Particulate Note(b)

93 584-84-9 Toluene Di-isocyanate, 2,4- 0.5 1 hr Health S Note(g) 0.2 Health 5 years

Note(a)

94 79-01-6 Trichloroethylene (TCE) 30 1 hr Health S Note(g) 12 Health 3 years

Note(a)

95 76-13-1 Trifluorotrichloro Ethane 2000000 1 hr Health S Note(f) 800000 Health Note(b)

96 7440-62-2 Vanadium 5 1 hr Health S 2 Health Note(b)

97 75-01-4 Vinyl Chloride 2.5 1 hr Health G Note(g) 1 Health 3 years

Note(a)

98 75-35-4 Vinylidene Chloride 25 1 hr Health S 10 Health Note(b)

99 1330-20-7 Xylenes 1825 1 hr Health Note(g) S Note(g) 730 3000 Health; Odour

5 years

Note(a)

100 7440-66-6 Zinc 100 1 hr Particulate Note(c) S 120 Particulate Note(b)

Note (a) From the date that the standard in Regulation 346 is amended for that specific contaminant. Note (b) These values are effective immediately for new applications for new facilities. These values are effective for all facilities on the date the new models become mandatory. Before the models

are mandatory, existing facilities may meet these values; otherwise, they must meet the corresponding values in Schedule 1. Note (c) Previous ½ hour averaging time POI numerical values are retained in Schedule 2 with a 1 hour averaging time period. Note (d) Previous ½ hour averaging time POIs are retained in the Schedules 1 and 2 until development of odour-based AAQCs. Note (e) Compliance will be based on AAQCs Only. Note (f) CFC Class 1 Listed (Refer to Part VI of the Ontario Environmental Protection Act R.S.O. 1990, C. E-19 and the applicable Regulations made under the Act, on the manufacture, use, storage,

disposal, etc., of these ozone depleting substances) Note(g) Standard currently being updated through consultation S = Air Quality Standard G = Air Quality Guideline