Draft Human Health Mitigation Plan – Background and Glossary

This glossary of terms is provided to help explain scientific terms and processes used in the air quality modeling completed by Metrolinx. We hope that this guide is a useful glossary to help you understand the scientific modeling completed during the Additional Review of Human Health Assessment.

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90^th Percentile Approach

• The 90^th percentile reflects that 90% of the results were below a given mark and that 10% of the results were above. In the case of the 2009 Environmental Assessment for the Georgetown South Project, the background air quality was established at the 90^th percentile for all scenarios.
• The hourly method we used in the current re‐assessment, in contrast, uses all of the available hourly data to refine the modeling which increases its accuracy.

Acute

• An acute effect happens within a short time after an exposure (i.e., may be minutes or days). An acute short‐term exposure can result in short‐ or long‐term health effects.

Air Quality Monitoring and Reporting Plan

• The GTS Project Air Quality Monitoring and Reporting Plan monitors a group of chemicals of concern from three reporting stations along the Georgetown rail corridor. Quarterly reports from the readings will be used to confirm whether the levels outlined in the Environmental Assessment and reassessed during the recent Additional Review of the Human Health Assessment work plan validate the conservative assumptions used in the modeling work.
• This plan was prepared in consultation with Toronto’s Medical Officer of Health, Environment Canada, the Ministry of the Environment and community representatives. It was approved by the Ministry of the Environment on June 2, 2010.

Background level

• A typical or average level or concentration of a chemical or substance in the environment, without any contribution from the proposed project (e.g. GTS Project).

Chemicals of Concern

• These are air contaminants that have been identified as possibly having an impact on the environment and/or human health.

Concentration

• The proportion of one substance contained in a given sample amount.

Environmental Assessment (EA)

• An environmental assessment is a process to evaluate the potential environmental effects of an infrastructure project. In Ontario, this process is governed by the Environmental Assessment Act and the Ministry of the Environment, under Ontario Regulation 231/08. Metrolinx completed the Georgetown South Project Environmental Study Report in July 2009. In October 2009, the Minister of the Environment approved the GTS Project subject to some conditions.

Exceedance

• When the modeled results show that the concentration of a chemical or substance is above the applicable guideline. For instance, any modeled result which shows the annual average concentrations of NO₂ above 40 μg/m³ is an exceedance of the World Health Organization guideline for annual NO₂.

Human Health Mitigation Plan

• Metrolinx’s plan to address any residual human health impact after implementing Tier 4 emission standards for the GO and Air Rail Link locomotive fleets on the Georgetown line.

Modeling Scenario

• A modeling scenario is predictive tool to assess a future hypothetical situation. Our approach involved modeling the emission levels for the following scenarios: full build, future no build and opening day scenarios. For the first two scenarios, the modeling was done for pre‐Tier and Tier 4 conditions. Opening day was only a pre‐Tier 4 scenario.
• Future Full Build: This is the maximum theoretical projection of train service on the Georgetown rail corridor. The actual future volumes will be significantly lower because of operating restrictions (e.g. capacity at Union Station) and actual passenger demand.
• Future No Build: This scenario reflects the number of additional train service that could theoretically be accommodated without any infrastructure improvements. In other words, this would be the amount of additional off‐peak train service that could be added using existing infrastructure. Since we are building more infrastructure, this scenario is purely hypothetical.
• Opening Day 2015: This is the number of trains that will be operating on opening day in 2015 with the expansion in infrastructure now underway.

Non‐Road Diesel Tier Emission Standards (Tier 0 to Tier 4)

• The United States Environmental Protection Agency (EPA) established exhaust emission standards to regulate emission limits for all types of newly‐manufactured or remanufactured diesel engines. The standards range from Tier 0 to the latest standard, Tier 4, which goes into effect in 2015. Each standard further reduces diesel emissions.
• Tier 4 reduces NO₂ and PM_2.5 emissions by up to 90%.
• GO Transit currently uses Tier 2 diesel locomotive engines. The latest standard available today.
• Tier 4 locomotive engines will be available for new locomotives beginning in 2015. The Air Rail Link and 10 GO locomotives will be Tier 4 on opening day in 2015. GO will refurbish the balance of its locomotive fleet to Tier 4 afterwards.

Ozone Limiting Method

• When oxides of nitrogen (NO_x) are emitted in diesel exhaust, the initial composition is dominated by nitric oxide (NO). Once in the air, some of the NO is oxidized in reaction with other pollutants (principally ground‐level ozone) to produce NO₂, which is the oxide of nitrogen that has the most significant health implications. Not all NO_x emissions convert to NO₂ in the air. The ozone limiting method was used to estimate the maximum short‐term NO₂ concentrations from NO_x emissions, to allow for a more accurate prediction of ground‐level NO₂.

Particulate Matter – Fine (PM_2.5)

• Airborne particulate matter describes a mixture of microscopic solid particles and liquid droplets suspended in air. Fine particulate matter refers to particles that are 2.5 microns in diameter – this is 30 times smaller than the diameter of human hair.
• At 2.5 microns, ultra‐fine particulate matter is captured in the PM_2.5 assessment
• Health Impact:
  Elevated levels above the regulatory benchmark, can lead to:
• Cardiopulmonary and respiratory disease
• Respiratory irritant

Nitrogen Dioxide (NO₂)

• Nitrogen is the most abundant element in the air. Oxides of nitrogen (NO_x), including nitric oxide (NO) and nitrogen dioxide (NO₂) gases, are produced during high temperature combustion, for example forest fires, transportation (combustion engine)
• Health Impact:
  On bad air (smog) days, the most sensitive individual will experience:
• Itchy eyes
• Shortness of breath during strenuous activity
• Respiratory irritation

Sensitive Receptor

• A sensitive receptor is a location where outdoor activity occurs often and represents a population that is more sensitive to air emissions than other members of a population. For example, children and the elderly are more sensitive to air emissions that an average adult.
• Our assessment included sensitive receptors such as schools, daycares, and seniors residents.
• This is a conservative approach to model the effects on the most sensitive population.

Sulphur Dioxide (SO₂)

• SO₂ is a colourless gas that smells like burnt matches ‐ it can also be oxidized to form sulphuric acid aerosols. It is produced primarily from the combustion of fossil fuels and is a precursor to sulphates, which are one of the main components of airborne fine particulate matter.
• Health Impact:
  Elevated levels above the regulatory benchmark can lead to:
• Cardiopulmonary and respiratory disease
• Respiratory irritation

In this section, we will provide you with highlights of the plan and discuss what we found, and what our plan is to mitigate human health impacts. We have provided the comprehensive findings and the detailed mitigation plan in the following tabs.

What we found

• No significant human health risk caused by future GO/Air Rail Link (ARL) service
• Tier 4 technology effectively reduces GO/ARL train engine emissions
• GO/ARL plays an important role in improving air quality by moving people out of cars and onto public transit
• Background air quality exceeds regulatory guidelines for some modeled chemicals of concern

Our Plan

• Monitor and Minimize GO/Air Rail Link emissions
• Implement air quality monitoring plan
• Install 3 air quality monitoring stations
• Use results of air quality monitoring to confirm modeling
• Implement Tier 4 technology for Air Rail Link and the entire GO locomotive fleet
• Air Rail Link and 10 GO trains will be Tier 4 on opening day; the rest of the GO fleet is scheduled to be refurbished to Tier 4 afterwards.
• Do our part to improve air quality in the region
• Through The Big Move, Metrolinx has a 25-year plan to create an integrated and sustainable transportation future for the Greater Toronto and Hamilton Area.
• One of the major objectives of The Big Move is to reduce transportation-related air emissions that will improve background air quality. By moving people by public transit and active transportation options (e.g. walking, cycling), Metrolinx will be doing its part to spare the air.
• Support government initiatives to improve air quality in the province
• Metrolinx is supporting government initiatives, such as the province’s Growth Plan and Go Green: Ontario’s Action Plan on Climate Change, through its planning and investment in expanding public transit and other active transportation options.

Since we received the Minister of Environment’s conditional approval, we have taken several steps to ensure that GO Transit continues to be a leader in adopting emission reducing technologies:

Ordered Diesel Multiple Units (DMUs) for the ARL Service

• On February 18, 2011, the Metrolinx Board of Directors approved a plan to purchase 12 Tier 4 Diesel Multiple Units (DMUs) for the Air Rail Link (ARL) service. The DMUs use the latest clean diesel technology and are convertible to electric propulsion.

Moved Ahead with Tier 4 Refurbishment of GO Locomotive Fleet

• A request for proposal will close in June 2011 to test prototype Tier 4 diesel locomotive engine technology and to refurbish 10 GO train locomotives by 2015. The rest of the locomotive fleet is scheduled to be refurbished to Tier 4 emission standards afterwards.

Recommended electrification of the GO Georgetown and Lakeshore Lines

• On January 26, 2011, the Metrolinx Board of Directors approved a staff recommendation to begin electrification of the Lakeshore and Georgetown GO Transit rail corridors in a phased approach. The new ARL service is identified as the first phase for electrification. The province has agreed to the commencement of the environmental assessment for the ARL service, which is now in progress.