Air and Dust Monitoring Summary Report

Toronto Transit Commission Air and Dust Monitoring Summary Report Monitoring Period: 1 May 31 May 2015 Air quality monitoring is currently ongoing as part of the dust control program associated with the Leslie Street Connection Track construction project. The objective of the dust control program is to protect the community from potential impacts of the construction dust on air quality. The monitoring program was developed to confirm the effectiveness of the dust control program in protecting the community. When assessing potential dust impacts from construction activities, it is the inhalable particulate (PM 10 ), with particle sizes of less than 10 μm, that is generally considered to be the most appropriate size fraction to monitor. PM 10 is commonly associated with the handling of aggregates and soils, wind erosion, road dust, and construction activities, and the provincial criterion is set based upon the potential health effects of PM 10. The larger particulates, with diameter of up to a size of 44 μm, are considered total suspended particulate (TSP), and the AAQC for TSP is based upon potential effects on visibility since airborne TSP is generally considered to be a nuisance. In Ontario, the objective is to maintain total PM 10 levels below the interim Ambient Air Quality Criterion (AAQC) of 50 micrograms per cubic metre (µg/m 3 ) over a 24-hour period. This AAQC is not a standard, but rather a concentration target for PM 10 that is considered to be protective of human health and the environment. PM 10 levels are currently being continuously monitored at three stations along Leslie Street using DustTrak TM DRX instruments. The monitoring stations were sited along the perimeter of the construction activities, rather than in the community, to allow the contractor to effectively use the PM 10 data to monitor dust levels and to employ additional dust control measures if short-term PM 10 concentrations are elevated. The average PM 10 concentration is recorded every 30-minutes, and the 48 daily readings are used to calculate 24-hour average concentrations that are shown in the summary table. The daily concentrations are provided as an indicator of dust levels near the construction, but are not directly comparable to the AAQC. A summary of the results of this continuous monitoring is provided in the Dust Monitoring Summary (page 3). As of February 2014, TTC is operating an -Sampler PM 10 dust monitor identified as CM2 on Leslie Street just south of Queen Street. The average PM 10 concentration is recorded every 15-minutes, and the 96 daily readings are used to calculate 24-hour average concentrations that are provided in the dust monitoring summary table. Page 1 of 6

Toronto Transit Commission Air and Dust Monitoring Summary Report Monitoring Period: 1 May 31 May 2015 In addition to the continuous PM 10 monitors used to provide feedback to the site, the TTC has been operating a community monitoring station on the rooftop of 843 astern Avenue since 2011. This station would be more indicative of community air quality impacts. The 24-hour average PM 10 concentration is measured once every six days at this station. Airborne TSP is also monitored at the community monitoring station, as well as a number of metals that may be present as constituents of the particulate matter. These sampling results are summarized in the Air Quality Summary (page 4). A windrose and graph of the monthly precipitation are also provided (page 5). The windrose presents the monthly wind data graphically, where the colours denote the wind speed and the length of each spoke corresponds to the frequency that the wind blows from a given direction as a percent of the total hours in each month. Page 2 of 6

Dust Monitoring Summary Report Toronto Transit Commission Continuous Dust (PM 10 ) Monitoring at Four Stations (Dust 2, Dust 3, Dust 6, and CM2) Monitoring Period: 1 May - 31 May 2015 PM 10 : Particulate Matter, less than 10 micrometres in diameter. µg/m 3 : Micrograms per cubic metre; a unit of measure for concentration in air. Date 24 Hour Average PM 10 Concentration Minimum Maximum (µg/m 3 ) (µg/m 3 ) Station(s) Where 24-hour Average > 50 µg/m 3* Predominant Wind Direction(s) 01-May-15 21 43 02-May-15 13 19 03-May-15 27 46 04-May-15 37 70 3,6 WNW 05-May-15 16 30 06-May-15 20 40 07-May-15 28 51 6 Various 08-May-15 46 64 3,6 W 09-May-15 59 82 All W 10-May-15 66 84 All Various 11-May-15 20 33 12-May-15 10 31 13-May-15 5 8 14-May-15 6 30 15-May-15 11 36 16-May-15 23 45 17-May-15 6 17 18-May-15 10 33 19-May-15 8 46 20-May-15 12 31 21-May-15 23 39 22-May-15 15 30 23-May-15 7 17 24-May-15 10 19 25-May-15 27 34 26-May-15 17 42 27-May-15 22 51 3 NW 28-May-15 22 30 29-May-15 39 62 2,3,6 WNW 30-May-15 32 84 3 NW 31-May-15 5 90 3 Various * 50 µg/m 3 is the interim Ontario Ministry of the nvironment Ambient Air Quality Criteria (AAQC) for PM 10. Comments Wind direction is reported by the direction from which it orginates. Data was collected at four (4) monitoring stations, three (3) stations equipped with DustTrak aerosol monitors and one (1) -Sampler that measure airborne PM 10. Three (3) of the monitors are located along the perimeter of the excavation area for the purpose of monitoring on-site dust levels. One (1) monitor identified as CM2 is located south of Queen Street on Leslie Street for the purpose of community dust monitoring.

Air Quality Monitoring Summary Report Toronto Transit Commission Discrete Particulate (PM 10 /TSP) and Metals Sampling at Station CM Ambient Air Quality Sampling at Community Monitoring Station Monitoring Period: May 2015 The air quality sampling results for fine particulate matter (PM 10 ), total suspended particulate (TSP), and metals presented were collected at the community monitoring station during the monitoring period as stated above. Sampling was conducted on a standard 6-day schedule. All concentrations are 24-hour average values. Fine Particulate Matter PM 10 and Total Suspended Particulate (TSP) PM 10 TSP May 2015 Summary Number of Samples 5 5 Average Concentration µg/m 3 38.6 99.2 Maximum Concentration µg/m 3 70.6 170.6 Minimum Concentration µg/m 3 19.5 62.4 Number of Days greater than Project Limit 1 1 Baseline Concentration (2011) µg/m 3 39.4 79 stablished Project Limit* µg/m 3 50 120 PM 10 : Particulate Matter less than 10 micron in diameter Metals The metals concentrations were determined from analysis of the total particulate matter samples collected. Arsenic Cadmium Chromium Lead Manganese Nickel May 2015 Summary Number of Samples 5 5 5 5 5 5 Average Concentration µg/m 3 <0.0040 0.0015 0.0044 0.0109 0.0606 0.0039 Maximum Concentration µg/m 3 <0.0047 0.0026 0.00779 0.0195 0.107 0.0059 Minimum Concentration µg/m 3 <0.0037 <0.0012 <0.0031 0.00712 0.0341 0.0023 Number of days greater than Project Limit 0 0 0 0 0 0 Baseline Concentration (2011) µg/m 3 0.004 0.001 0.005 0.014 0.041 0.005 stablished Project Limit* µg/m 3 0.3 0.025 1.5 0.5 2.5 2 *stablished Project limits are based on the criteria submitted in the Ambient Air Monitoring Plan approved by the MO. TT93749 Page 4 of 6

Air Quality Monitoring Summary Report Toronto Transit Commission Meteorological Data Summary (May 2015) WRPLOT View - Lakes nvironmental Software Figure 1.0 - Monthly Wind Rose (Source: On-Site Meteorological Station ) 30 Total Preciptation (mm) 25 20 15 10 5 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Figure 2.0 - Monthly Precipitation: May 2015 (Source: On-Site Meteorological Station) TT94739 Page 5 of 6

ST T A TR N S QU NU HB RUS N AV TR AS K ROO N I S NU L LS AV T T M TR TR Y S OSL LAK R SHO RD VA AS T L BOU NOTS: 1. TH LOCATION OF ACH MONITORING STATIONS INDICATD ON TH PLAN MAY B SUBJCT TO CHANG IN ORDR TO NSUR THAT TH STATIONS MT TH ONTARIO MINISTRY OF TH NVIRONMNT SITING CRITRIA FOR AN AMBINT AIR MONITORING STATION AND AR NOT OBSTRUCTD BY TRS OR OTHR SIT FATURS. 2. TH COMMUNITY MONITORING STATION (CM) IS OPRATD BY AMC, AND TH DUST MONITORING STATIONS AR OPRATD BY SPL (STATIONS 2,3 AND 6). AD C RO I RV H RT O N S STATION 2 0 30 90 150m SCAL CLINT LOGO: DWN BY: CLINT: ZF TORONTO TRANSIT COMMISSION PROJCT CHK'D BY: LL TITL DATUM: Amec Foster Wheeler nvironment & Infrastructure 3190 Steeles Avenue ast, Unit #305 Markham, Ontario L3R 1G9 PROJCTION: SL SCAL: AS SHOWN ASHBRIDGS BAY LRV MAINTNANC AND STORAG FACILITY LSLI STRT CONNCTION TRACK DUST AND AMBINT AIR MONITORING STATIONS LAK SHOR BOULVARD AST & LSLI STRT, TORONTO, ONTARIO DAT: APRIL 2015 PROJCT NO: TT93731.2 TT93749 RV. NO.: A FIGUR No. 3