by Haley & Aldrich, Inc. Boston, Massachusetts on behalf of ARE-MA Region No. 45, LLC Cambridge, Massachusetts Pasadena, California

Transcription

1 AMBIENT AIR MONITORING PLAN 100 BINNEY STREET CAMBRIDGE, MASSACHUSETTS RTNS (100 BINNEY STREET), (300 THIRD STREET), (BMR DISPOSAL SITE), AND (DPS AT 100 BINNEY STREET) by Haley & Aldrich, Inc. Boston, Massachusetts on behalf of ARE-MA Region No. 45, LLC Cambridge, Massachusetts Pasadena, California for Massachusetts Department of Environmental Protection Wilmington, Massachusetts File No June 2015

2 TABLE OF CONTENTS Page List of Tables List of Figures ii ii 1. Introduction OVERVIEW SITE BACKGROUND SCHEDULE FOR AIR MONITORING Background Monitoring Daily Monitoring Periodic Analytical Sampling 3 2. Systems and Procedures PERIMETER AIR MONITORING LOCATIONS Stationary Air Monitoring Station Portable Air Monitoring MONITORING PROCEDURES AND EQUIPMENT VOCs Dust (PM10) Odors 5 3. Action Levels and Field Response Actions TVOC ACTION LEVEL VOC ACTION LEVEL DUST (PM10) ACTION LEVEL ODORS CONTINGENCY PLAN 9 4. Equipment Calibration and QA/QC Procedures Data Summaries FIELD DOCUMENTATION LABORATORY SAMPLE RESULTS 11 Tables Figures

3 List of Tables Table No. F-I Title Acceptable Ambient Air Screening Levels for Detected COC - VOCs F-2 Comparison of Estimated Air Concentrations to Acceptable Air Concentrations List of Figures Figure No. Title F-1 Proposed Air Monitoring Station Location Plan ii

4 1. Introduction Haley & Aldrich, Inc. (Haley & Aldrich) has prepared this Ambient Air Monitoring Plan (AAMP) to establish the requirements, methods, and validation of ambient air monitoring activities planned during proposed construction activities at 100 Binney Street in Cambridge, Massachusetts (hereafter referred to as the Site ). Haley & Aldrich has developed and will implement this site-specific AAMP. Although it is anticipated that control measures will mitigate fugitive dust and volatiles originating from construction activities, this evaluation is intended to assess hypothetical exposures to potentially sensitive receptors in the vicinity of the Site. Health and safety monitoring for on-site personnel is not addressed in this AAMP. Health and safety monitoring for on-site personnel is managed through site-specific Health and Safety Plans (HASPs) developed by the Contractor and Haley & Aldrich for their respective personnel. Details of the site characterization, planned remediation activities, and the schedule of work to be conducted at the Site are provided in the Release Abatement Measure (RAM) Plan to which this is appended dated 15 June 2015, and the RAM Plan titled Release Abatement Measure (RAM) Plan, 100 Binney Street, Cambridge, Massachusetts, RTNs (BMR Disposal Site), (DPS at 100 Binney Street), and (100 Binney Street), dated 30 April The AAMP was developed to support the activities described in the two RAM Plans. The AAMP uses references to information, data, and figures that are contained in the aforementioned RAM Plans. 1.1 OVERVIEW Potential emissions of vapor-phase volatile organic compounds (VOCs), odors, and polynuclear aromatic hydrocarbons (PAHs) and inorganic metals adhered to particulates (dusts) may occur when contaminated soils are excavated or otherwise disturbed. Site remediation of contaminated soils, including the planned jet grouting, TCLP lead failed soil treatment, pre-excavation, and mass excavation, have the potential to impact ambient air. Perimeter air monitoring will be conducted by Haley & Aldrich during the above mentioned construction activities to monitor vapor and dust concentrations. The Contractor will be responsible for monitoring worker exposures within the work zone and implementing measures to reduce the VOC vapors, odors, and dust if the perimeter action levels are exceeded or to meet action levels for workers within the work zone. Mitigation measures to control VOC vapors, odors from low odor threshold compounds Hydrogen Sulfide (H 2 S) and naphthalene, and dust, and respective action levels for each are described herein. 1.2 SITE BACKGROUND The Site consists of approximately 1.25 acres of land located at 100 Binney Street in Cambridge, Massachusetts. Properties in the surrounding area are generally commercial and residential in nature. A daycare center is located at the corner of West Kendall Street and Linksey Way, approximately 100 ft from the Site. The Site is bordered by Binney Street to the north, Second Street to the east, Linskey Way to the south and the existing building at 300 Third Street to the west. An existing building, 41 Linskey Way, is situated at the southeast corner outside the limits of the RAM activities and the Site. The Site is 1

5 currently paved, and most recently used as an at-grade parking lot. A perimeter fence is in-place to restrict access to the Site. The Site is being developed into a 10-story office and laboratory facility with 2 to 3 levels of underground parking and mechanical space; excavation to construct these below-grade levels will extend 30 to 45 ft bgs. Analytical testing of Site media indicate that on-site fill and natural soils contain volatile organic compounds (VOCs), semi-volatile organic compounds (SVOCs), metals, and petroleum hydrocarbons at levels above the applicable Massachusetts Contingency Plan RCS-1 Reportable Concentrations for Soil. Contaminants generally present in fill material include petroleum hydrocarbons, polycyclic aromatic hydrocarbons (PAHs) and metals (arsenic, barium, cadmium, lead, and mercury). In addition to the presence of urban fill, contamination at the Site has also been attributed to on- and off-site point sources, including: Former on-site underground storage tanks (USTs) on the eastern portion of the property; Off-site releases from a former manufactured gas plant (MGP) at the BMR property at 77 Linskey, which has resulted in the presence of contamination including dense non-aqueous phase liquid (DNAPL) at the southwest corner of the Site in two zones: upper zone from El. 8 to El. -2 and lower zone from approximately El.-17 to El. -30; and Off-site release of mineral spirits/paint thinner (resulting in elevated levels of VOCs, primarily xylenes) from 300 Third Street, which has resulted in elevated levels of xylenes in the west and northwest portion of the Site, at depths ranging from approximately 5 to 20 ft bgs. 1.3 SCHEDULE FOR AIR MONITORING Air monitoring will occur at the Site during jet grouting operations and during mass excavation of contaminated soil. Based on the preliminary construction schedule for Site work, the anticipated duration of air monitoring for remedial construction is approximately four months and will be conducted over two phases: 1. during jet grouting operations, pre-trenching for slurry wall, and TCLP Lead treatment (approximately 1 month) and 2. during mass-excavation (approximately 3 months). Programmatic ambient air quality monitoring as outlined by this AAMP is not anticipated to be necessary during Site construction activities conducted after potential air emission sources of OHM have been removed from the Site. Perimeter nuisance dust monitoring may be conducted during postremediation construction activities under the general construction work health & safety plans. Perimeter air monitoring during non-working hours (nights and weekends) is not expected to be required Background Monitoring Background measurements of ambient air quality will be made each morning prior to the start of excavation or site ground work. The purpose of the background air quality data collection is to test the equipment and methods for implementing the AAMP during construction, while additionally providing a snapshot of background air quality conditions. Evaluations of background and/or upwind ambient air conditions will be collected daily using hand-held 2

6 instruments. Action Levels established in the AAMP for TVOCs and PM10 are site activity-related action levels; actionable above daily elevated background conditions in ambient air that are beyond the control of the Project Daily Monitoring Monitoring of VOC vapors and dust will be conducted daily during jet grouting operations and during excavation of contaminated soils at the perimeter of the Site using real-time instruments. Periodic, as-needed monitoring of Hydrogen Sulfide (H2S) will be conducted during excavation of organic deposits. Emphasis will be on areas of the Site located near the daycare center as well as downwind locations. The daycare center located at the corner of West Kendall Street and Linksey Way will be monitored during active construction work in areas were oil and hazardous materials (OHM) impacted soils are present and have the potential to generate emissions of chemical vapors, particulates, or odors to ambient air. Specific sampling and locations will be evaluated and updated as needed based on construction activities and weather conditions Periodic Analytical Sampling Vapors are anticipated during excavation of the post-jet-grouted solidified soil, MGP residuals and xylene impacted soils. At the beginning of jet grouting operations, an initial 2-hr grab sample will be collected at the perimeter of the Site using a summa canister and analyzed for VOCs using USEPA method TO-15. In addition, an 8 hour composite sample will be collected the same day for comparison purposes. Additional grab and composite samples will be collected for analytical testing as deemed necessary depending on the activities underway and the results measured compared to Site action levels and contingency plans, as outlined in Section 3. 3

7 2. Systems and Procedures Environmental perimeter air monitoring will be conducted during excavation of remediation waste to observe dust and vapor levels in ambient air. The perimeter air monitoring systems are intended to evaluate ambient air conditions related to Site activities to guide mitigation measures and to document potential exposures to the general public. This sampling program is designed to provide real-time air monitoring so that calculated action levels are maintained and acceptable risks are not exceeded. As mentioned previously herein, laboratory analytical results for VOC detected in ambient air will be evaluated periodically to evaluate the effectiveness of this AAMP. 2.1 PERIMETER AIR MONITORING LOCATIONS Stationary Air Monitoring Station Haley & Aldrich will establish a stationary perimeter air monitoring station contained in a weather resistant enclosure along the perimeter boundary of the Site. The station will be outfitted with a PID, a dust monitor, and a summa canister when needed. The location of the station will be adjusted based on Site construction activities and weather conditions. The station will be placed as close to the controlled Site perimeter boundary or along the property line as feasible. The purpose of the station is to monitor emissions from remedial construction activities that are migrating from the Site beyond the perimeter of the Site area. Refer to the attached Figure 1 for approximate location of Air Monitoring Station Portable Air Monitoring An additional PID and dust monitor as well as a Hydrogen sulfide meter will be used as hand-held monitors for surveying perimeter air quality measurements in real-time (5-minute averages) for VOCs, PM10, and H 2 S, respectively. The PID and dust monitor will be used to monitor ambient air at the perimeter of the Site on an hourly basis and periodically in front of the nearby daycare center. Perimeter air monitoring for H 2 S will be conducted at the fence line if rotten egg odors are noted during excavation of the organic soils. Refer to the attached Figure 1 for approximate locations of portable air monitoring locations. Additional or different perimeter monitoring locations may be selected due to the location, nature and intensity of remedial construction activities. Locations of and modification to monitoring locations, will be documented daily in the field activity logbook. 2.2 MONITORING PROCEDURES AND EQUIPMENT VOCs The concentration of total VOCs (TVOCs) in ambient air at the perimeter is used as a surrogate measure in real time of the potential vapor emissions. TVOCs will be monitored throughout daily as outlined in Section 1. Field screening for TVOCs will require a volatile organic compound (VOC) photoionization detector (PID) meter with a 11.7 or 10.2 ev lamp, depending on the location of work at the Site. The PID 4

8 will capable of a detection range from units of ppbv to elevated ppmv. A ppbrae (or equivalent) will be used to monitor TVOCs. The RAE will be setup to collect and log 5-minute time-weighted averages of TVOCs throughout each work day. Air samples for the determination of VOCs will be collected as outlined in Section and summarized in Table 1. Samples will be collected using laboratory-provided, batch-certified clean, passivated 6-liter stainless steel evacuated (vacuum) air sampling canisters. Each canister will be equipped with a laboratory-provided, batch-certified clean, vacuum flow regulator calibrated by the laboratory for either grab sampling or 8 hour sampling. Vacuum canisters for air sampling will be set to collect the ambient air sample from a height of approximately 4 to 6-feet above the ground. Canister air samples will be managed and shipped under chain-of-custody to a MassDEP-approved certified air laboratory for analysis by USEPA Method TO-15 GC/MS. Table 1: Analytical VOC Sampling Summary Task Sample Type Turn-Around Time Frequency Jet-Grouting Grab (2 hour) and 8-hr 72-hour Initial (Initial) composite Jet-Grouting (2 week period) 8 hour 72-hour One per week after the initial General Excavation 8 hour Standard (5 business days) 1 per month Unique circumstances or data use requirements may warrant the request for expedited turnaround analysis by the laboratory. All submittals of air samples for expedited analysis should be pre-approved by the laboratory Dust (PM10) Visual monitoring for dust conditions will be performed in the work area and at the Site perimeter during RAM activities at the Site. In addition, dust will also be monitored with a portable dust meter (TSI 8530 Dust Trak II or equivalent) for field screening for PM10 in ambient air. If visible dust is noted or if two or more consecutive 5-minute averages for PM10 are greater than the Action Level, dust mitigation measures will be implemented. The Contractor shall be responsible for implementing measures to reduce dust if visible dust is noted or the Action Levels are exceeded at the fence line. At a minimum, standard dust control such as wateringdown the exposed ground surface or spreading hygroscopic salts will be employed where heavy equipment will be traveling and dust is generated Odors MGP residuals may contain chemical constituents (primarily naphthalene and H 2 S) that have distinctive odors. The principal odor of concern for both health risk and public nuisance is the tar camphor or mothball odor indicating the possible presence of naphthalene-, derivatives in the air. The odor threshold and intensity of odor for tar camphor will be qualitatively used in the AAMP to mitigate the emissions of odors beyond the controlled Site boundary. Aggressively controlling perceptible odor 5

9 intensities at the Site boundary will support the overall control of chemical risk in fugitive air emissions during the remediation, and is a requirement to control and mitigate fugitive nuisance odors that may be unpleasant to the surrounding community. Observations of the presence and intensity of odors in ambient air at the perimeter of the Site will be recorded each day throughout the duration of the jet grouting operations and excavation of contaminated soils. The Contractor will be required to implement odor control measures as needed. These may include, but not be limited to the use of odor control suppressant foam and/or the placement of plastic sheeting over containment areas or stockpiles. Perimeter air monitoring will be conducted for H 2 S at the fence line if rotten egg odors are noted during excavation of the organic soils using a portable gas meter capable of measuring H 2 S down to 1 ppb. It is planned to implement measures to reduce H 2 S if the Action Levels in Section 3 are exceeded at the fence line. 6

10 3. Action Levels and Field Response Actions Action levels are established vapor-phase emissions of TVOCs, individual VOCs, dust (particulates as PM10), and H 2 S. The initial screening risk action levels for VOCs and PM10 are based on the estimated construction schedule for the planned duration of construction within contaminated areas (approximately four months). A summary of action levels for fence line ambient air monitoring are shown below: 5-minute avg. (ppmv) VOC Vapors 8-hour air sample (µg/m 3 ) TVOC 5 1,2,4-Trimethylbenzene 4,300 Xylenes (Mixed Isomers) 3,40 Naphthalene 26 Benzene 86* Ethylbenzene 77,000 Toluene 43,000 Abbreviations: VOC: Volatile organic compounds PM10: ppmv: Parts per million volume µg/m 3 : Micrograms per cubic meter of air TWA: Time-Weighted Average *corresponds to 27 ppb as measured by the portable ppbrae PID Threshold Values - Action Levels 24-hour TWA (µg/m 3 ) Dust (PM10) 2-hour avg. (µg/m 3 ) Short-Duration 12-hour avg. (µg/m 3 ) 98 (70 ppb) Hydrogen Sulfide (H 2 S) Longer-Duration 12-hour avg. (µg/m 3 ) 56 (40 ppb) 24-hour avg. (µg/m 3 ) 28 (20 ppb) Mitigation measures to control vapors (TVOC and VOC), dust, and odors (H 2 S and MGP-related) and respective action levels for each are described herein. 3.1 TVOC ACTION LEVEL The action level for volatile TVOC vapors at the perimeter fence line is 5 ppmv sustained for more than 5 minutes. If this threshold is exceeded mitigation actions will be taken to control and reduce the vapor levels. Mitigation measures include the application of vapor suppressing foams or coverings and modification of excavation procedures to expose less contaminated soil or the use of ventilation system to increase air flow in the excavation. Naphthalene (moth ball) type odors will likely require some mitigation controls to neutralize, or absorb odors with the application of odor neutralization agents. 3.2 VOC ACTION LEVEL A Site specific risk-based air concentration was calculated for VOC compounds of concern at the Site. A review of soil data that is representative of soil that is planned to be disturbed during Site construction indicates that among volatile OHM detected, 1,2,4-trimethylbenzene, xylenes, naphthalene, benzene, ethylbenzene, and toluene were detected the most frequently and at the highest concentrations. Therefore, ambient air screening levels were calculated for these OHM. 7

11 Table F-1 provides documentation of the derivation of air screening levels. As indicated in the Table, screening levels were calculated assuming exposure to vapors for 12 hours per day, five days per week, for 17 weeks (~4 months). This provides a conservative estimate of the duration of jet grouting operations and excavation activities associated with the MGP-impacted soils. Screening levels were calculated using subchronic reference concentrations published by MassDEP and a target hazard index of 1 for each compound. Screening levels based on carcinogenic effects were derived for benzene, using the unit risk factor published by MassDEP and a target cancer risk of 1E-06. The screening action levels provided in Table F-1 are intended to be used to evaluate a running average concentration for 8-hour air samples over the duration of the excavation activities. The action level for benzene will be measured using the portable ppbrae that corresponds to an action level 27 ppb. To provide perspective on whether excavation of soil within the MGP-impacted area may result in air concentrations that exceed the screening levels, the Site wide maximum detected concentrations were used to estimate ambient air concentrations. As shown in Table F-2, with exception of xylenes, estimated air concentrations are lower than the ambient air screening levels. This indicates that if the average soil concentrations encountered during the excavation activities are commensurate with those used in this modeling, there is a low likelihood that air screening levels would be exceeded. 3.3 DUST (PM10) ACTION LEVEL The daily (24-hour) PM10 standard is supported by the EPA as protective of human health from the effects of short-term exposures to coarse particles in ambient air. Use of the 24-hour PM10 standard for the actionable screening threshold (5-minute action level for PM10 at the Site perimeter) is conservative. If the 24-hour PM10 standard of 150 µg/m 3 is not exceeded in a sustained short-term period of three consecutive 5-minute averages during the active working hours of the day, it is not likely to be exceeded, on average, over the entire day including as many as hours of relative inactivity on-site. In addition, in order to evaluate the action level for total dust in terms of potential health risks to nearby residents, nearby commercial workers, and passers-by due to chemical constituents in Site soil aerosolized into particulate, the PM10 value used in the exposure equations in the RAM FRC, was set to 150 µg/m 3. According to the FRC, dose calculations (ADDs) performed for nearby adult and child residents who may be exposed to fugitive dust generated from Site soil during RAM and construction activities, a condition of No Significant Risk of harm to human health exists for current Site soil conditions. Therefore, the NAAQS PM10 value of 150 µg/m 3 is protective for health risks associated with potential exposures to dust. If ambient concentrations of PM10 exceed 150 µg/m 3 (0.150 mg/m 3 ) for one 5-minute average, construction work can continue but additional mitigation actions will be taken to control and maintain dust levels below the action level. Mitigation actions may include watering-down the exposed ground surface or spreading hygroscopic salts will be employed where heavy equipment will be traveling and dust is generated. 3.4 ODORS A quantitative scale of odor intensities is not proposed for use in this AAMP. The objective of the air field technician is to recognize conditions of unacceptable odors and require as necessary odor 8

12 suppression controls (foaming or modifying work procedures) in order to minimize the presence and intensities of odors at the perimeter of the controlled Site. If sustained elevated levels of odors are observed off-site, work may be stopped until engineering controls or modifications to the work procedures abate the intensity of the odor emissions. 3.5 CONTINGENCY PLAN A communication protocol has been established by the Owner with the surrounding tenants and building owners. Charcoal filters are planned to be installed within air intakes of the occupied buildings (See Figure 1) adjacent to the site prior to start of construction in contaminated areas. If complaints are received from tenants, the charcoal filters will be inspected and replaced as necessary. Extra charcoal filters will be available on stand-by when needed. The contractor will be notified of the complaints and will be asked to add or adjust engineering controls as necessary such as spraying of odor suppressant foams and/or covering of soil with sheeting. 9

13 4. Equipment Calibration and QA/QC Procedures Calibration of instrumentation will occur in accordance with each of the equipment manufacturer s calibration and quality assurance requirements. The VOC and PM10 monitors will be calibrated daily, and calibrations will be recorded in the field activity logbook. 10

14 5. Data Summaries 5.1 FIELD DOCUMENTATION Daily data summaries will be prepared to document the field screening results for the day. The summaries will include the locations monitored, 5-minute TWA results for TVOCs and PM10, the date and time of the reading, location-specific observations on odors, weather conditions, or site activities related to air quality, and the daily maximum value and daily average values for each day. Monitoring results logged on instruments will be downloaded daily to the field technician s laptop computer. The results of the monitoring program will be summarized and included in weekly field reports which are distributed to the project team. Perimeter air monitoring results will also be made available to the contractor s Certified Industrial Hygienist to supplement Health & Safety monitoring data as applicable. 5.2 LABORATORY SAMPLE RESULTS Laboratory sample results will be reviewed and tabulated as soon as possible after receipt from the laboratory and compared to the real-time data collected during the sampling period. The analytical results will be evaluated and compared to calculated Site action levels. G:\34250\002 to 040 series 100 Binney\ B Environmental\MCP\Health & Safety\AAMP\ HAI-100 Binney-AAMP-FINAL.docx 11

15 TABLE F-1 ACCEPTABLE AMBIENT AIR SCREENING LEVELS FOR DETECTED COC - VOCs 100 BINNEY STREET CAMBRIDGE, MA Page 1 of 1 Calculation of Acceptable Ambient Air Concentration Screening Levels Project-Specific Parameters EF construction Exposure Frequency (dy/yr) 85 project-specific assumption = (5 dys/wk) (17 wks/yr). ED construction Exposure Duration (years) 0.3 project-specific assumption = (17 wks)/(52 wks/yr). FD construction Fraction of Day (unitless) 0.50 project-specific assumption = (12 hrs/24 hrs). THI Hazard Index noncancer 1 TR Target Risk carcinogenic 1E-06 MDEQ ELCR target - modified for (2) COCs for carcinogenic risk basis Cancer Risk Noncancer Hazard Acceptable Ambient Air subchronic Risk-Based Risk-Based Concentration Detected COPC CAS No. IUR key RfC inh key Concentration Concentration Screening Level basis (µg/m³) -1 (mg/m³) (µg/m³) (µg/m³) (µg/m³) 1,2,4-Trimethylbenz1,2,4-Trimethylbenzene E-01 MADEP E E+03 nc Xylenes (Mixed IsomXylenes (Mixed Isomers) E-01 MADEP E E+03 nc Naphthalene Naphthalene E-03 MADEP E E+01 nc Benzene Benzene E-06 MADEP 1.0E-02 MADEP 2.4E E E+01 nc Ethylbenzene Ethylbenzene E+00 MADEP E E+04 nc Toluene Toluene E+00 MADEP E E+04 nc Calculation of Acceptable Risk-Based Concentrations (RBC) for Site Worker Inhalation Noncancer Hazard RBC nc (ug/m3) = HI * ATnc (365 days/yr * 0.3) * CF (1000 ug/mg) EF (85 days/yr) * ED (0.3) * FD (0.5) * 1/RfC (mg/m3) Cancer Risk RBC c (ug/m3) = TR * ATc (365 days/yr * 70 yr) EF (85 days/yr) * ED (0.3) * FD (0.5) * 1/IUR (ug/m3) Key: MADEP Massachusetts Department of Environmental Protection, Vlookup Version v0414.xlsx C Inhalation Unit Risk. Consolidated Table of OEHHA/ARB Approved Risk Assessment Health Values; Table 1, updated 02/14/2011. HEAST-sc RfD USEPA Health Effects Summary Tables. The RfC was calculated from the HEAST Oral Subchronic RfD as follows: (RfC = RfD (mg/kg/day) x 70 kg/20 m3-day). IRIS-c USEPA Integrated Risk Information System. Inhalation Chronic RfC. IRIS-c RfD USEPA Integrated Risk Information System. The RfC was calculated from the IRIS Oral Chronic RfD as follows (RfC = RfD (mg/kg/day) x 70 kg/20 m3-day). PPRTV-sc Provisional Peer Reviewed Toxicity Values for Superfund - subchronic RfC. PPRTV-sc RfD Provisional Peer Reviewed Toxicity Values for Superfund. The RfC was calculated from the PPRTV Oral Subchronic RfD as follows: (RfC = RfD (mg/kg/day) x 70 kg/20 m3-day). * Toxicity reference concentrations are not available for this aliphatic hydrocarbons; petroleum hydrocarbons aromatics C9-C10 was used as a surrogate. FOOTNOTES: ABBREVIATIONS: COPC - Compound of Potential Concern. IUR - Inhalation Unit Risk (cancer). RfC inh - Reference Concentration for Inhalation (noncancer). Haley & Aldrich, Inc. G:\34250\002 to 040 series 100 Binney\ B Environmental\MCP\Health & Safety\AAMP\ HAI- revised AAC derivation_inhvocs -v(2).xlsx 6/12/2015

16 TABLE F-2 COMPARISON OF ESTIMATED AIR CONCENTRATIONS TO ACCEPTABLE AIR CONCENTRATIONS 100 BINNEY STREET CAMBRIDGE, MA Page 1 of 1 COPC Maximum Soil VF Air Acceptable Air Concentration (mg/kg) (m³/kg) (µg/m³) (µg/m³) 1,2,4-Trimethylbenzene Xylenes (Mixed Isomers) Naphthalene Benzene Ethylbenzene Toluene VF: Volatilization factor calculated in Attachment B-1 in Appendix G. Air equation: Air (µg/m³) = Soil (mg/kg) x 1000 ug/mg / VF (m³/kg). Acceptable air concentration is calculated in Table F-1. Haley & Aldrich, Inc. G:\34250\002 to 040 series 100 Binney\ B Environmental\MCP\Health & Safety\AAMP\ HAI- revised AAC derivation_inhvocs -v(2).xlsx 6/12/2015

17 LEGEND: M-1 S-1 DESIGNATION AND APPROXIMATE LOCATION OF MOBILE MONITORING STATION DESIGNATION AND APPROXIMATE LOCATION OF STATIONARY MONITORING STATION NOTES: 1. PLAN PREPARED FROM DRAWING C-4 ENTITLED COMPOSITE UTILITY PLAN, BINNEY STREET, CAMBRIDGE, MA, PREPARED BY KLEINFELDER DATED 30 MAY ELEVATIONS ARE IN FEET AND REFERENCE THE CAMBRIDGE CITY BASE (CCB) DATUM. ERVIN, DAYNA Printed: 6/12/2015 9:51 AM Layout: B469 J:\GRAPHICS\34250\ B476.DWG SCALE IN FEET 100 BINNEY STREET DEVELOPMENT CAMBRIDGE, MASSACHUSETTS PROPOSED AIR MONITORING STATION LOCATION PLAN SCALE: AS SHOWN JUNE 2015 FIGURE F 1 1

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