Brownfields Site Evaluation Criteria

Transcription

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2 Chittenden County Brownfields Program FY 2017 Project Name: McClure Center Brownfields Site Evaluation Criteria Address/Project Location: 241 North Winooski Applicant: Waite-Heindel, on behalf of Champlain Housing Trust Reviewer: Emily Nosse-Leirer Required Characteristics Possible Points Scoring Is the property owner willing to sign a Participation Agreement and Site Access Yes Yes = continue Does the site meet DEC eligibility criteria for petroleum sites and/or EPA eligibility Yes No = Not eligible Is the planned use consistent with current zoning? Yes Project Location (10 pts Total) Is the project located in Burlington or Winooski? (Yes=2, No=0) 2 Is the project located in a Center, Enterprise, Metro, Suburban or Village Regional Planning Area (as identified in the most recently adopted regional plan)? (Yes=2, No=0) 2 Is the project located within a designated state center? (Including areas with pending applications) (Yes=2, No=0) 2 Does the project site have existing water, sewer, electric, transportation and/or natural gas infrastructure serving it? (Yes=2, No=0) 2 Is the project located adjacent to another brownfields site? (Yes=2, No=0) 2 Project Location Economic Conditions (5 pts Total) Is the project located in an area where the poverty rate is higher than the Countywide average? Up to 5 points 5 Housing Potential (30 points total) Will site cleanup enable housing development in an area planned for high density housing or mixed-use development by the municipality? Will site cleanup contribute to alleviating identified housing need as identified in relevant adopted municipal documents? Will site cleanup allow multiple housing units (in excess of what is already on site) to be built? Commercial Potential (20 points total) Will site cleanup enable commercial development in an area planned for high density commercial or mixed-use development by the municipality and region? Is the project a mixed-use project? Open Space and Recreation Potential (10 points total) Up to 10 points 1/2 point per unit, 20 points maximum. Up to 20 points Will site cleanup enable improvement or construction of a park in an area where it can be readily accessed by an underserved population? Will site cleanup involve creating or improving open or recreational space as part of a Project Economic Impact (25 pts Total) Does the project have the potential to create or retain jobs? If no direct jobs are created or retained, does the project lead to indirect job creation? Does the project have other economic development benefits? Up to 10 points 10 1 point per FTE job, up to 10 points Up to 15 points 10 5 Initial Score 100 points possible 40 Bonus Categories If the project will enable housing unit construction, will a percentage of them be perm 1/2 point per percentage point affordable, up to 20 points. 0 Is the developer/property owner willing to pay for the Phase I or pay for part of the Ph Up to 15 points 0 Does proposed site cleanup mitigate impacts to surface water? Up to 10 points 0 Additional Notes: What is anticipated value of final investment, if known? What is project timeline, if known? Bonus Score 45 points possible TOTAL SCORE 40 0 As approved 10/28/2016 by the CCRPC Brownfields Advisory Committee Forms Modified from Windham Regional Brownfields Initiative

3 Spring 2017 Vapor Intrusion Assessment Report Phase I Environmental Site Assessment Residential Property Multi-Generational Facility No. Winooski Ave Burlington, Vermont VT DEC Site # ATC Project No. 280EM00066 Prepared for: Mr. Donal Dugan Champlain Housing Trust 88 King Street Burlington, Vermont Prepared by: ATC Group Services LLC 171 Commerce Street Williston, Vermont July 18, 2017

4 TABLE OF CONTENTS 1.0 INTRODUCTION Site Background VAPOR INTRUSION ASSESSMENT Vapor Point Screening Air Sampling FINDINGS RECOMMENDATIONS RELIANCE...8 FIGURES Figure 1 Figure 2 Figure 3 Figure 4 Site Locus Map Vapor Point Location and Pressure Field Screening Result Diagram PCE Air Sampling Result Diagram Groundwater Monitoring Well Location Map TABLE Table 1 Air Sampling Results APPENDICES Appendix A Laboratory Analytical Reports

5 1.0 INTRODUCTION ATC Group Services LLC (ATC) has been retained to conduct assessment activities at the Multi-Generational Building located at North Winooski Avenue, in Burlington, Vermont (the site). The following report presents a summary of on-going assessment activities at the site between May 30, 2017 and June 1, The site currently operates as a multi-tenant space occupied by child care space, a senior center, and a human advocacy office space. The site location is shown on a Site Locus Map presented as Figure 1. Site assessment activities were requested by the VT DEC due to the historical presence of chlorinated solvent impacted subsurface soils and groundwater at the site. 1.1 Site Background The subject property was identified as a former dry cleaner and designated as a hazardous waste site in Groundwater monitoring wells were installed in 1994 and 1998 and a number of underground storage tanks were also removed during that period. The groundwater sampling results from 1994 indicated a release of chlorinated solvents had impacted groundwater above the Vermont Groundwater Enforcement Standard (VGES). In 1996 limited soil vapor extraction was performed to decrease the amount of tetrachloroethene (PCE) from the subsurface. In 1998 additional UST s were removed and ground water sampling was performed by ATC Associates Inc. (ATC) which continued to show levels above the VGES. On September 23, 2011 ground water sampling was conducted by ATC, which indicated PCE concentrations in groundwater had remained similar to concentrations identified in The Vermont Department of Environmental Conservation, Sites Management Section (SMS), requested in a letter dated October 31, 2012, a vapor intrusion investigation to determine if PCE is affecting the indoor air of the facility. The request was based on the levels of PCE in the soil vapor recovery system when it was turned off in The tests performed in 1999 used an analysis that had a relatively high detection limit compared with Vermont s current standards, which are detailed in the Investigation and Remediation of Contaminated Properties Procedures (IROCPP), dated April 5, 2012, as well as the use of the property for a daycare were taken into account by the VT DEC. ATC conducted several vapor assessments at the site which indicated vapor intrusion from the subsurface into the onsite building was a concern. A contractor was hired by Champlain Housing Trust to install a subslab depressurization (SSD) system within the building which was completed in late ATC conducted testing and sampling at the facility after the system was installed, which indicated indoor concentrations of chlorinated VOCs improved by remained at concentrations above standards. ATC recommended that amendments to the SSD system be performed to increase the radius of influence in the Children s Center portion of the building. According to information relayed to ATC, another SSD extraction point (suction pit) was installed on the southern side of the building in the Children s Center. The exhaust stack was also extended to be approximately 15 feet above the roof surface, and the building air handling system was optimized to create a positive pressure in the building. ATC was requested to conduct follow-up sampling after the SSD system amendment which is summarized below. The work was completed pursuant to the ATC Proposal for Groundwater and Air Sampling, dated March 23, ATC Group Services LLC Spring 2017 Vapor Intrusion Assessment Report Multi-Generational Building Burlington, VT July 2017 Page 1

6 2.0 GROUNDWATER MONITORING 2.1 Ground Water Measurement Two wells are currently located on site, MW-2R and MW-1. ATC attempted to measure water levels from well MW-2R on May 30, The groundwater monitoring well MW-2 was previously destroyed during construction activities. The well MW-1 is obstructed at a depth of approximately feet, and ATC did not expect to collect a groundwater sample from the well. ATC attempted to gauge the depth to water in well MW-2R utilizing an electronic interface probe. The monitoring well MW-2R was found to be dry at the time of sampling to a depth of feet below the top of casing. Therefore, a groundwater sample was not collected for laboratory analysis during the May 2017 gauging and sampling event. 3.0 VAPOR INTRUSION ASSESSMENT 3.1 Vapor Point Screening ATC measured differential pressure utilizing a Dwyer Series 475 Mark III Digital Manometer in each of the existing vapor points on May 30, The vapor point locations are presented on Figure 2. The results of the measurements are presented in the following table and a diagram indicating the pressure readings is presented on Figure 2. TABLE 1 Vapor Point Pressure Readings Vapor Point February 11, 2016 May 30, 2017 Vapor Point Location Number Pressure (in WC) Pressure (in WC) VP-2 Laundry Room, Main Hallway VP-3 Senior Center Janitors Closet VP-5 Children Center Staff Roof VP-6 Outright Vermont Conference Room VP-7 Senior Center Dining Room VP-8 Senior Center Arts & Crafts Room VP-9 Children s Center Afterschool Room VP-10 Children s Center Preschool Room VP-11 Children s Center Little Toddlers Kitchen The pressure readings indicating slight increases from the previous sampling in a majority of the vapor points, and significant increases in several of the Children s Center vapor points VP-5 and VP-11. The approximate radius of influence is presented on Figure 2. The most heavily impacted (with VOCs) vapor points from previous sampling events (VP-3, VP-5 and VP-7) were within the SSD system radius of influence and negative pressure was measured in the subslab for each of those vapor points. Additional outlying vapor points VP-6, VP-8, VP-9, and VP-10 continued to indicate no pressure influence from the mitigation system. ATC Group Services LLC Spring 2017 Vapor Intrusion Assessment Report Multi-Generational Building Burlington, VT July 2017 Page 2

7 3.2 Air Sampling ATC conducted a site visit on June 1, 2017 to collect two sub-slab vapor samples from VP-5 and VP-7, three indoor air samples, an outdoor sample, and a sample at the SSD system exhaust stack. 6-Liter Summa canisters with 8-hour regulators were utilized to collect the indoor and outdoor samples, and canisters with 30 minute regulators were utilized to collect the sub-slab vapor samples. All of the samples were submitted to Con-Test Analytical Laboratory, of East Longmeadow, MA for analysis of five chlorinated compounds (including PCE) via EPA Method TO-15. The two sub-slab vapor points selected for sampling, were purged and screened with a MiniRAE Model PGM photoionization detector (PID) (calibrated with isobutylene) prior to Summa canister sample collection. The PID exhaust air was filtered with a carbon filter and a secondary PID was utilized to screen the exhaust air to confirm the filter was effective. The PID measurements are presented in the following table. TABLE 2 Vapor Point Screening Levels Vapor Point Number Vapor Point Location PID Reading (ppm) VP-5 Children s Center Staff Room 0.0 VP-7 Senior Center Dining Room 0.0 The vapor point leak testing was conducted per the SOP Leak testing the Vapor Pin TM, which included utilization of a water dam during the well purging. The vapor point seal via the water dam was confirmed, and the sub-slab vapor sampling was conducted. ATC collected indoor air samples via Summa canisters on June 1, 2017, simultaneously with the vapor point sampling. The three indoor samples were located in the Senior Center Dining Area (IA-1), the main hallway outside the laundry room (IA-3), and in the hallway outside the Children s Center staff room (IA-2). A blank sample was also collected for QA/QC purposes. The previous sampling results were compared to the Vapor Intrusion Screening Values Table (Table C7) within the Investigation and Remediation of Contaminated Properties Procedure (IROCPP) dated April The VT DEC has created a new Rule that will become effective July 27, 2017 titled The Investigation and Remediation of Contaminated Properties Rule (IRule). The IRule has new Vapor Intrusion Values presented in Appendix A of the Rule. The comparison standards for both the IROCPP and the IRule are presented below. ATC Group Services LLC Spring 2017 Vapor Intrusion Assessment Report Multi-Generational Building Burlington, VT July 2017 Page 3

8 INDOOR AIR SAMPLES PCE (µg/m3) TABLE 3 Air Sampling Results Summary Cis-1,2-DCE (µg/m3) Trans-1,2- DCE (µg/m3) TCE (µg/m3) VC (µg/m3) IA-3 Laundry 0.29 ND ND ND ND IA-1 Senior Center IA-2 Children s Center 0.24 ND ND ND ND ND ND ND ND ND AS-02 Outdoor ND ND ND ND ND AS-01 SSD Outdoor Exhaust ND 35 ND AS-03 - Blank ND ND ND ND ND 2012 IROCPP VI Screening Value-Target Indoor Air* (ug/m3) 2017 IRule VT Air Screening Levels** (ug/m3) Resident Air/Industrial Air 0.57 NA NA /5.11 NA NA 0.2/ /1.86 VAPOR POINT SAMPLES VP-5 Children s Center VP-7 Senior Center Dining Room VI Screening Value-Shallow Soil Gas* (ug/m3) 2017 IRule Sub-Slab Soil Gas** (ug/m3) Resident Air/Industrial Air Notes: 5600 ND ND 32 ND ND ND ND 5.7 NA NA /170 NA NA 6.7/23 3.7/62 * -Vapor Intrusion Screening Value-Target Indoor Air from Table C.7 in the IROCPP **-Vapor Intrusion Values from Appendix A in the IRule. Cis-1,2-DCE Cis-1,2-Dichloroethene Trans-1,2-DCE Trans-1,2-Dichloroethene TCE Trichloroethene VC Vinyl Chloride The results indicate the PCE concentrations for the three indoor air samples (AS-01, AS-04 and AS-06) were below the 2012 IROCPP Vapor Intrusion Screening Value (VI Screening Value) and below the soon to be adopted 2017 IRule Vapor Intrusion Values for Residential Air. The reported concentrations in each of the samples from indoor air and the vapor points decreased from the previous sampling event. A sample was collected from the outdoors on the roof of the building near a fresh air intake for the building HVAC system. The sample location was approximately 20 feet to the south of the SSD system exhaust stack which was extended to approximately 15 feet above the roof elevation. The results of the outdoor sample did not indicate a detectable concentration of PCE. A sample was also collected from the SSD system exhaust stack which indicated high concentrations of PCE and TCE were being removed from the ATC Group Services LLC Spring 2017 Vapor Intrusion Assessment Report Multi-Generational Building Burlington, VT July 2017 Page 4

9 subslab air. The exhaust PCE sample result decreased from 4,700 µg/m 3 during the previous sampling event to 1,800 µg/m 3 during the 2017 sampling event indicating the subslab VOC vapor concentrations are decreasing. The two sub-slab vapor point sampling results indicated concentrations decreased significantly from previous sampling conducted in the same vapor points. The sample collected from the senior center (VP- 7) reported TCE concentrations decreased from 68 µg/m 3 to 17 µg/m 3, and the sample from the children s center decreased from 9,500 µg/m 3 to 5,600 µg/m 3. The PCE result from sample VP-7 in the Senior Center exceeds the IROCPP VI Screening Value, but does not exceed the new IRule Sub-Slab Soil Gas standard for Residential Air. The PCE and TCE concentrations in sample VP-5 remained above the IROCPP VI Screening Value for Shallow Soil Gas, and above the IRule Sub-Slab Soil Gas standard for Residential Air. The results indicate a subsurface source of chlorinated solvents remains. The SSD system appears to be reducing the VOC concentrations and extended run time should further reduce the measured concentrations. A vapor point VOC contour diagram is presented as Figure 3. A blank sample was submitted for laboratory analysis and did not indicate reportable concentrations of VOCs. ATC Group Services LLC Spring 2017 Vapor Intrusion Assessment Report Multi-Generational Building Burlington, VT July 2017 Page 5

10 4.0 FINDINGS Based on data generated during this investigation, ATC presents the following findings related to subsurface contamination at the North Winooski Ave. Burlington, Vermont property: ATC attempted to collect a groundwater sample from the onsite monitoring wells. The well MW-2R was found to be dry at the time of sampling and a water sample was not collected. The well MW-1 has an obstruction that has prevented sampling in this well since prior to Pressure differential measurements collected from the vapor points indicated the subslab depressurization (SSD) system was effectively causing a negative subslab pressure in the most heavily contaminated vapor points. The additional extraction point (suction pit) installed in the Children s Center portion of the building increased the radius of influence in this portion of the building. Indoor air sampling conducted on June 1, 2017 indicated PCE was present at concentrations below the IROCPP VT DEC VI Screening Value for Target Indoor Air and below the IRule Vapor Intrusion Values, in the three indoor samples collected. The PCE concentrations decreased in each of the samples when compared to the pre-ssd system installation sampling. Two of the existing vapor points (VP-5 and VP-7 located in the children s center and senior center respectively) were sampled for chlorinated VOCs simultaneously with the indoor air samples on June 1, The results from sample VP-7 indicated the PCE concentrations exceeded the IROCPP VI Screening Value for shallow soils, but did not exceed the IRule Sub-Slab Soil Gas Residential Air values. The PCE and TCE concentrations in VP-5 exceeded the IROCPP VI Screening Value and the IRule Sub-Slab Soil Gas Residential Air Value. The VOC concentrations decreased significantly in both samples from pre-ssd system installation sampling. An SSD system exhaust stack sample was collected and an outdoor air sample was collected near a HVAC air intake located approximately 20 feet away from the SSD exhaust stack. The samples were collected simultaneously with the sub-slab and indoor air sampling on June 1, The SSD exhaust stack sample indicated chlorinated VOCs were being exhausted from the building subslab, but concentrations significantly decreased from the previous sampling event in The results indicate the sub-slab vapor concentrations of chlorinated solvents are decreasing. The outdoor sample did not indicate the presence of VOCs which indicates the SSD exhaust air is not being drawn into the building. ATC Group Services LLC Spring 2017 Vapor Intrusion Assessment Report Multi-Generational Building Burlington, VT July 2017 Page 6

11 5.0 CONCLUSIONS AND RECOMMENDATIONS The air sampling results indicate the subslab depressurization system (SSD) is working effectively and has reduced indoor air concentrations to below VT DEC standards. The radius of influence of the SSD system appears to have improved after the 2017 addition of another suction pit. The entire building footprint does not appear to be covered by the SSD system; however, the most contaminated areas appear to be under negative pressure. The sub-slab sampling results indicate significantly decreased VOC concentrations, and ATC would expect the concentrations to continue to reduce with the operational SSD system. The SSD system should be regularly inspected and maintained. If additional confirmatory samples are desired, ATC could collect indoor and sub-slab air samples to confirm the SSD system is working effectively. Conduct an annual groundwater sampling event in the fall of ATC Group Services LLC Spring 2017 Vapor Intrusion Assessment Report Multi-Generational Building Burlington, VT July 2017 Page 7

12 6.0 RELIANCE This report is for the use and benefit of, and may be relied upon by Champlain Housing Trust, and any affiliates and third parties authorized in writing by Champlain Housing Trust and ATC, including the lender(s) in connection with a secured financing of the property, and their respective successors and assigns. Any third party agrees by accepting this report that any use or reliance on this report shall be limited by the exceptions and limitations in this report, and with the acknowledgment that actual property conditions may change with time, and that hidden conditions may exist at the property that were not discovered within the authorized scope of the assessment. Any use by or distribution of this report to third parties, without the express written consent of ATC, is at the sole risk and expense of such third party. ATC makes no other representation to any third party except that it has used the degree of care and skill ordinarily exercised by environmental consultants in the preparation of the report and in the assembling of data and information related thereto. No other warranties are made to any third party, either expressed or implied. Unless otherwise agreed upon in writing by ATC and a third party, ATC s liability to any third party authorized to use or rely on this report with respect to any acts or omissions shall be limited to a total maximum amount of $100,000. Respectfully Submitted, ATC Group Services LLC Adam Forman Thomas J. Broido Project Geologist Branch Manager for ATC for ATC Direct Line Direct Line adam.forman@atcassociates.com tom.broido@atcassociates.com Cc: Richard Spiese, VT DEC ATC Group Services LLC Spring 2017 Vapor Intrusion Assessment Report Multi-Generational Building Burlington, VT July 2017 Page 8

13 FIGURES

14 Asbestos Containing Roof Caulking at Chimney North Parking Area Flashing Material (Trace Amount of Asbestos) Front of School Figure 1 Address: Site Locus Map Multi-Generational Facility No. Winooski Ave. Burlington, Vermont Project Number: 280EM00066 SOURCE : Field Notes 171 Commerce St. Williston, Vermont Phone:(802) Fax: (802) SCALE: Not to scale

15 ? 0.05? VP ? 2.00 VP VP VP VP VP VP VP Legend? 0.00? VP-07 - Vapor Point - Subslab Depressurization Suction Pits Relative Pressure Result (in W.C.) - Approximate Pressure Result Contour? - Actual Extent Unknown 171 Commerce Street, P.O Box 1486 Williston, VT Ph. (802) VP-09

16 VP-03 NS VP-08 NS IA VP VP-02 NS IA VP-06 NS VP-05 5,600 VP-10 NS IA-2 ND VP-09 NS NS Legend IA-3 VP Indoor Air Sampling Location - Vapor Point - PCE Concentration in Air Sampling Result (ug/m3) 171 Commerce Street, P.O Box 1486 Williston, VT Ph. (802) VP-11

17 MW-01 North Parking Area Multi- Generational Facility Parking Area MW-02R Groundwater Monitoring Well Location Map Address: Multi-Generational Facility No. Winooski Ave. Burlington, Vermont Project Number: 280BS00066 SOURCE : Field Notes 171 Commerce St. Williston, Vermont Phone:(802) Fax: (802) SCALE: Not to scale

18 TABLE

19 Table 1 Air Sample Results Sample No. Sample Date Analysis Result (ug/m 3 ) cis-1,2-dichloroethene trans-1,2-dichloroethylene Tetrachloroethylene Trichloroethylene Vinyl Chloride INDOOR AIR AS-01 Laundry 12-Sep-14 EPA TO-15 <0.14 < <0.19 < Mar-15 EPA TO < <0.090 (IA-3) 8-Mar-16 EPA TO < < Jun-17 EPA TO-15 <0.14 < <0.19 <0.090 AS-04 Senior Center 7-Feb-14 EPA TO-15 NA NA 1.3 NA NA 12-Sep-14 EPA TO-15 <0.14 < <0.19 < Mar-15 EPA TO-15 <0.14 < <0.19 <0.090 (IA-1) 8-Mar-16 EPA TO-15 <0.14 < < Jun-17 EPA TO-15 <0.14 < <0.19 <0.090 AS-06 Children's Center 7-Feb-14 EPA TO-15 NA NA 0.98 NA NA 12-Sep-14 EPA TO-15 <0.14 < <0.19 < Mar-15 EPA TO-15 <0.14 < <0.19 <0.090 (IA-2) 8-Mar-16 EPA TO-15 <0.14 < <0.29 < Jun-17 EPA TO-15 <0.14 <0.14 <0.24 <0.19 <0.090 AS-07 Outdoor 12-Sep-14 EPA TO-15 <0.14 <0.14 <0.24 <0.19 < Mar-15 EPA TO-15 <0.14 <0.14 <0.24 <0.19 <0.090 (AS-02) 8-Mar-16 EPA TO-15 <0.14 < <0.19 < Jun-17 EPA TO-15 <0.14 <0.14 <0.24 <0.19 <0.090 AS-01 Outdoor Exhaust 8-Mar-16 EPA TO < Jun-17 EPA TO < <2.6 VI Screening Value-Target Indoor Air (ug/m3) NE NE IRule Vapor Intrusion Values, Vermont Air Screening Levels (ug/m3). (Resident Air/Industrial Air)- NE NE 0.63/ / /1.86 Sample No. Sample Date Analysis Result (ug/m 3 ) cis-1,2-dichloroethene trans-1,2-dichloroethylene Tetrachloroethylene Trichloroethylene Vinyl Chloride VAPOR POINT SAMPLING VP-2 Laundry 12-Sep-14 EPA TO < Mar-15 EPA TO <0.51 VP-3 Senior Center 12-Sep-14 EPA TO-15 <0.79 < < Mar-15 EPA TO <0.51 VP-5 Children's Center 12-Sep-14 EPA TO < < Mar-15 EPA TO <2.6 8-Mar-16 EPA TO-15 <2.0 < <1.3 1-Jun-17 EPA TO-15 <7.9 < <5.1 VP-7 Senior Center Dining Room 25-Mar-15 EPA TO <2.6 8-Mar-16 EPA TO < < Jun-17 EPA TO < <0.54 <0.26 VP-8 Senior Center Arts & Crafts Room 25-Mar-15 EPA TO-15 < <0.51 VP-10 Children's Center Preschool Rm 25-Mar-15 EPA TO-15 <0.79 < <1.1 <0.51 VP-11 Children's Center Little Toddlers Kitchen 25-Mar-15 EPA TO-15 < <0.51 VI Screening Value-Shallow Soil Gas (ug/m3) NE NE IRule Vapor Intrusion Screening Values, Sub-slab Soil Gas (ug/m3). (Resident Air/Industrial Air)- NE NE 21/ /23 3.7/62 Notes: Vapor Intrusion Screening Value-Target Indoor Air from Table C.7 in the IROCPP < = Less than the laboratory's quantitation limit. ug/m 3 = micrograms per cubic meter NE = No level established by the VTDEC. Yellow shaded indicated that the detected concentration exceeded the Vapor Intrusion Screening Values. Multi-Generational Building Burlington, VT ATC Project No. 280EM00066

20 APPENDIX A

21 Table of Contents 39 Spruce Street * East Longmeadow, MA * FAX 413/ * TEL. 413/ June 14, 2017 Adam Forman ATC Group Services LLC - Vermont 171 Commerce Street, PO Box 1486 Williston, VT Project Location: Multi-Gen - Burlington, VT Client Job Number: Project Number: [none] Laboratory Work Order Number: 17F0164 Enclosed are results of analyses for samples received by the laboratory on June 2, If you have any questions concerning this report, please feel free to contact me. Sincerely, James M. Georgantas Project Manager Page 1 of 20

22 Table of Contents Table of Contents Sample Summary 3 Case Narrative 4 Sample Results 5 Sample Preparation Information 13 QC Data 14 Air Toxics by EPA Compendium Methods 14 B Flag/Qualifier Summary 15 Certifications 16 Chain of Custody/Sample Receipt 17 Page 2 of 20

23 Table of Contents ATC Group Services LLC - Vermont 171 Commerce Street, PO Box 1486 Williston, VT ATTN: Adam Forman 39 Spruce Street * East Longmeadow, MA * FAX 413/ * TEL. 413/ PURCHASE ORDER NUMBER: [TOC_1]Sample Summary[TOC] REPORT DATE: 6/14/2017 PROJECT NUMBER: [none] ANALYTICAL SUMMARY WORK ORDER NUMBER: 17F0164 The results of analyses performed on the following samples submitted to the CON-TEST Analytical Laboratory are found in this report. PROJECT LOCATION: Multi-Gen - Burlington, VT FIELD SAMPLE # LAB ID: MATRIX SAMPLE DESCRIPTION TEST SUB LAB IA-3 Hall 17F Indoor air EPA TO-15 IA-2 Children's 17F Indoor air EPA TO-15 IA-1 Senior 17F Indoor air EPA TO-15 AS-02 Roof 17F Ambient Air EPA TO-15 AS-01 Effluent 17F Ambient Air EPA TO-15 AS-03 Blank 17F Field Blank EPA TO-15 VP-5 Children's 17F Sub Slab EPA TO-15 VP-7 Senior 17F Sub Slab EPA TO-15 Page 3 of 20

24 Table of Contents 39 Spruce Street * East Longmeadow, MA * FAX 413/ * TEL. 413/ [TOC_1]Case Narrative[TOC] CASE NARRATIVE SUMMARY All reported results are within defined laboratory quality control objectives unless listed below or otherwise qualified in this report. Qualifications: EPA TO-15 RL-11 Elevated reporting limit due to high concentration of target compounds. Analyte & Samples(s) Qualified: 17F [AS-01 Effluent], 17F [VP-5 Children's] The results of analyses reported only relate to samples submitted to the Con-Test Analytical Laboratory for testing. I certify that the analyses listed above, unless specifically listed as subcontracted, if any, were performed under my direction according to the approved methodologies listed in this document, and that based upon my inquiry of those individuals immediately responsible for obtaining the information, the material contained in this report is, to the best of my knowledge and belief, accurate and complete. Lisa A. Worthington Project Manager Page 4 of 20

25 Table of Contents 39 Spruce Street * East Longmeadow, MA * FAX 413/ * TEL. 413/ [TOC_1]Sample Results[TOC] ANALYTICAL RESULTS Project Location: Multi-Gen - Burlington, VT Date Received: 6/2/2017 Field Sample #: IA-3 Hall Sample ID: 17F Sample Matrix: Indoor air Sampled: 6/1/ :08 Sample Description/Location: Sub Description/Location: Canister ID: 2178 Canister Size: 6 liter Flow Controller ID: 3245 Sample Type: 8 hr Work Order: 17F0164 Initial Vacuum(in Hg): -30 Final Vacuum(in Hg): -4 Receipt Vacuum(in Hg): -5.7 Flow Controller Type: Fixed-Orifice Flow Controller Calibration RPD Pre and Post-Sampling: EPA TO-15 ppbv ug/m3 Date/Time Analyte Results RL Flag/Qual Results RL Dilution Analyzed Analyst cis-1,2-dichloroethylene ND ND /13/17 19:21 CMR trans-1,2-dichloroethylene ND ND /13/17 19:21 CMR Tetrachloroethylene /13/17 19:21 CMR Trichloroethylene ND ND /13/17 19:21 CMR Vinyl Chloride ND ND /13/17 19:21 CMR Surrogates % Recovery % REC Limits 4-Bromofluorobenzene (1) /13/17 19:21 Page 5 of 20

26 Table of Contents 39 Spruce Street * East Longmeadow, MA * FAX 413/ * TEL. 413/ ANALYTICAL RESULTS Project Location: Multi-Gen - Burlington, VT Date Received: 6/2/2017 Field Sample #: IA-2 Children's Sample ID: 17F Sample Matrix: Indoor air Sampled: 6/1/ :14 Sample Description/Location: Sub Description/Location: Canister ID: 2143 Canister Size: 6 liter Flow Controller ID: 3101 Sample Type: 8 hr Work Order: 17F0164 Initial Vacuum(in Hg): -30 Final Vacuum(in Hg): -5 Receipt Vacuum(in Hg): -5.7 Flow Controller Type: Fixed-Orifice Flow Controller Calibration RPD Pre and Post-Sampling: EPA TO-15 ppbv ug/m3 Date/Time Analyte Results RL Flag/Qual Results RL Dilution Analyzed Analyst cis-1,2-dichloroethylene ND ND /13/17 20:14 CMR trans-1,2-dichloroethylene ND ND /13/17 20:14 CMR Tetrachloroethylene ND ND /13/17 20:14 CMR Trichloroethylene ND ND /13/17 20:14 CMR Vinyl Chloride ND ND /13/17 20:14 CMR Surrogates % Recovery % REC Limits 4-Bromofluorobenzene (1) /13/17 20:14 Page 6 of 20

27 Table of Contents 39 Spruce Street * East Longmeadow, MA * FAX 413/ * TEL. 413/ ANALYTICAL RESULTS Project Location: Multi-Gen - Burlington, VT Date Received: 6/2/2017 Field Sample #: IA-1 Senior Sample ID: 17F Sample Matrix: Indoor air Sampled: 6/1/ :25 Sample Description/Location: Sub Description/Location: Canister ID: 2224 Canister Size: 6 liter Flow Controller ID: 3402 Sample Type: 8 hr Work Order: 17F0164 Initial Vacuum(in Hg): -30 Final Vacuum(in Hg): -7 Receipt Vacuum(in Hg): -6.4 Flow Controller Type: Fixed-Orifice Flow Controller Calibration RPD Pre and Post-Sampling: EPA TO-15 ppbv ug/m3 Date/Time Analyte Results RL Flag/Qual Results RL Dilution Analyzed Analyst cis-1,2-dichloroethylene ND ND /13/17 21:07 CMR trans-1,2-dichloroethylene ND ND /13/17 21:07 CMR Tetrachloroethylene /13/17 21:07 CMR Trichloroethylene ND ND /13/17 21:07 CMR Vinyl Chloride ND ND /13/17 21:07 CMR Surrogates % Recovery % REC Limits 4-Bromofluorobenzene (1) /13/17 21:07 Page 7 of 20

28 Table of Contents 39 Spruce Street * East Longmeadow, MA * FAX 413/ * TEL. 413/ ANALYTICAL RESULTS Project Location: Multi-Gen - Burlington, VT Date Received: 6/2/2017 Field Sample #: AS-02 Roof Sample ID: 17F Sample Matrix: Ambient Air Sampled: 6/1/ :34 Sample Description/Location: Sub Description/Location: Canister ID: 1722 Canister Size: 6 liter Flow Controller ID: 3246 Sample Type: 8 hr Work Order: 17F0164 Initial Vacuum(in Hg): -30 Final Vacuum(in Hg): -7 Receipt Vacuum(in Hg): -6.6 Flow Controller Type: Fixed-Orifice Flow Controller Calibration RPD Pre and Post-Sampling: EPA TO-15 ppbv ug/m3 Date/Time Analyte Results RL Flag/Qual Results RL Dilution Analyzed Analyst cis-1,2-dichloroethylene ND ND /13/17 22:01 CMR trans-1,2-dichloroethylene ND ND /13/17 22:01 CMR Tetrachloroethylene ND ND /13/17 22:01 CMR Trichloroethylene ND ND /13/17 22:01 CMR Vinyl Chloride ND ND /13/17 22:01 CMR Surrogates % Recovery % REC Limits 4-Bromofluorobenzene (1) /13/17 22:01 Page 8 of 20

29 Table of Contents 39 Spruce Street * East Longmeadow, MA * FAX 413/ * TEL. 413/ ANALYTICAL RESULTS Project Location: Multi-Gen - Burlington, VT Date Received: 6/2/2017 Field Sample #: AS-01 Effluent Sample ID: 17F Sample Matrix: Ambient Air Sampled: 6/1/ :21 Sample Description/Location: Sub Description/Location: Canister ID: 1968 Canister Size: 6 liter Flow Controller ID: 3185 Sample Type: 8 hr Work Order: 17F0164 Initial Vacuum(in Hg): -30 Final Vacuum(in Hg): -5 Receipt Vacuum(in Hg): -5.9 Flow Controller Type: Fixed-Orifice Flow Controller Calibration RPD Pre and Post-Sampling: EPA TO-15 Sample Flags: RL-11 ppbv ug/m3 Date/Time Analyte Results RL Flag/Qual Results RL Dilution Analyzed Analyst cis-1,2-dichloroethylene /13/17 23:20 CMR trans-1,2-dichloroethylene ND 1.0 ND /13/17 23:20 CMR Tetrachloroethylene /13/17 23:20 CMR Trichloroethylene /13/17 23:20 CMR Vinyl Chloride ND 1.0 ND /13/17 23:20 CMR Surrogates % Recovery % REC Limits 4-Bromofluorobenzene (1) /13/17 23:20 Page 9 of 20

30 Table of Contents 39 Spruce Street * East Longmeadow, MA * FAX 413/ * TEL. 413/ ANALYTICAL RESULTS Project Location: Multi-Gen - Burlington, VT Date Received: 6/2/2017 Field Sample #: AS-03 Blank Sample ID: 17F Sample Matrix: Field Blank Sampled: 6/1/ :00 Sample Description/Location: Sub Description/Location: Canister ID: 2010 Canister Size: 6 liter Flow Controller ID: Sample Type: 8 hr Work Order: 17F0164 Initial Vacuum(in Hg): - Final Vacuum(in Hg): - Receipt Vacuum(in Hg): Flow Controller Type: Fixed-Orifice Flow Controller Calibration RPD Pre and Post-Sampling: EPA TO-15 ppbv ug/m3 Date/Time Analyte Results RL Flag/Qual Results RL Dilution Analyzed Analyst cis-1,2-dichloroethylene ND ND /13/17 16:43 CMR trans-1,2-dichloroethylene ND ND /13/17 16:43 CMR Tetrachloroethylene ND ND /13/17 16:43 CMR Trichloroethylene ND ND /13/17 16:43 CMR Vinyl Chloride ND ND /13/17 16:43 CMR Surrogates % Recovery % REC Limits 4-Bromofluorobenzene (1) /13/17 16:43 Page 10 of 20

31 Table of Contents 39 Spruce Street * East Longmeadow, MA * FAX 413/ * TEL. 413/ ANALYTICAL RESULTS Project Location: Multi-Gen - Burlington, VT Date Received: 6/2/2017 Field Sample #: VP-5 Children's Sample ID: 17F Sample Matrix: Sub Slab Sampled: 6/1/ :02 Sample Description/Location: Sub Description/Location: Canister ID: 1006 Canister Size: 6 liter Flow Controller ID: 4107 Sample Type: 30 min Work Order: 17F0164 Initial Vacuum(in Hg): -29 Final Vacuum(in Hg): -4.5 Receipt Vacuum(in Hg): -4.7 Flow Controller Type: Fixed-Orifice Flow Controller Calibration RPD Pre and Post-Sampling: EPA TO-15 Sample Flags: RL-11 ppbv ug/m3 Date/Time Analyte Results RL Flag/Qual Results RL Dilution Analyzed Analyst cis-1,2-dichloroethylene ND 2.0 ND /13/17 23:56 CMR trans-1,2-dichloroethylene ND 2.0 ND /13/17 23:56 CMR Tetrachloroethylene /13/17 23:56 CMR Trichloroethylene /13/17 23:56 CMR Vinyl Chloride ND 2.0 ND /13/17 23:56 CMR Surrogates % Recovery % REC Limits 4-Bromofluorobenzene (1) /13/17 23:56 Page 11 of 20

32 Table of Contents 39 Spruce Street * East Longmeadow, MA * FAX 413/ * TEL. 413/ ANALYTICAL RESULTS Project Location: Multi-Gen - Burlington, VT Date Received: 6/2/2017 Field Sample #: VP-7 Senior Sample ID: 17F Sample Matrix: Sub Slab Sampled: 6/1/ :06 Sample Description/Location: Sub Description/Location: Canister ID: 1133 Canister Size: 6 liter Flow Controller ID: 4106 Sample Type: 30 min Work Order: 17F0164 Initial Vacuum(in Hg): -30 Final Vacuum(in Hg): -3 Receipt Vacuum(in Hg): -2.2 Flow Controller Type: Fixed-Orifice Flow Controller Calibration RPD Pre and Post-Sampling: EPA TO-15 ppbv ug/m3 Date/Time Analyte Results RL Flag/Qual Results RL Dilution Analyzed Analyst cis-1,2-dichloroethylene /13/17 22:43 CMR trans-1,2-dichloroethylene ND 0.10 ND /13/17 22:43 CMR Tetrachloroethylene /13/17 22:43 CMR Trichloroethylene ND 0.10 ND /13/17 22:43 CMR Vinyl Chloride ND 0.10 ND /13/17 22:43 CMR Surrogates % Recovery % REC Limits 4-Bromofluorobenzene (1) /13/17 22:43 Page 12 of 20

33 Table of Contents 39 Spruce Street * East Longmeadow, MA * FAX 413/ * TEL. 413/ Sample Extraction Data [TOC_1]Sample Preparation Information[TOC] Prep Method: TO-15 Prep-EPA TO-15 Pre-Dil Pre-Dil Default Actual Lab Number [Field ID] Batch Pressure Dilution Pre Dilution Initial ml Final ml Injection ml Injection ml Date 17F [IA-3 Hall] B N/A /13/17 17F [IA-2 Children's] B N/A /13/17 17F [IA-1 Senior] B N/A /13/17 17F [AS-02 Roof] B N/A /13/17 17F [AS-01 Effluent] B N/A /13/17 17F [AS-03 Blank] B N/A /13/17 17F [VP-5 Children's] B N/A /13/17 17F [VP-7 Senior] B N/A /13/17 Page 13 of 20

34 Table of Contents 39 Spruce Street * East Longmeadow, MA * FAX 413/ * TEL. 413/ QUALITY CONTROL Air Toxics by EPA Compendium Methods - Quality Control [TOC_1]QC Data[TOC] [TOC_2]Air Toxics by EPA Compendium Methods[TOC] Analyte ppbv ug/m3 Spike Level Results RL Results RL ppbv Source Result %REC %REC Limits RPD RPD Limit Flag/Qual Batch B TO-15 Prep [TOC_3]B179239[TOC] Blank (B BLK1) Prepared & Analyzed: 06/13/17 cis-1,2-dichloroethylene trans-1,2-dichloroethylene Tetrachloroethylene Trichloroethylene Vinyl Chloride ND ND ND ND ND Surrogate: 4-Bromofluorobenzene (1) LCS (B BS1) Prepared & Analyzed: 06/13/17 cis-1,2-dichloroethylene trans-1,2-dichloroethylene Tetrachloroethylene Trichloroethylene Vinyl Chloride Surrogate: 4-Bromofluorobenzene (1) Page 14 of 20

35 Table of Contents 39 Spruce Street * East Longmeadow, MA * FAX 413/ * TEL. 413/ FLAG/QUALIFIER SUMMARY [TOC_1]Flag/Qualifier Summary[TOC] * QC result is outside of established limits. Wide recovery limits established for difficult compound. Wide RPD limits established for difficult compound. # Data exceeded client recommended or regulatory level ND Not Detected RL DL MCL Reporting Limit Method Detection Limit Maximum Contaminant Level Percent recoveries and relative percent differences (RPDs) are determined by the software using values in the calculation which have not been rounded. No results have been blank subtracted unless specified in the case narrative section. RL-11 Elevated reporting limit due to high concentration of target compounds. Page 15 of 20

36 Table of Contents Certified Analyses included in this Report Analyte EPA TO-15 in Air cis-1,2-dichloroethylene trans-1,2-dichloroethylene Tetrachloroethylene Trichloroethylene Vinyl Chloride 39 Spruce Street * East Longmeadow, MA * FAX 413/ * TEL. 413/ CERTIFICATIONS Certifications AIHA,FL,NY,VA,ME AIHA,NJ,NY,VA,ME AIHA,FL,NJ,NY,VA,ME AIHA,FL,NJ,NY,VA,ME AIHA,FL,NJ,NY,VA,ME [TOC_1]Certifications[TOC] The CON-TEST Environmental Laboratory operates under the following certifications and accreditations: Code Description Number Expires AIHA AIHA-LAP, LLC - ISO17025: /1/2018 MA Massachusetts DEP M-MA100 06/30/2017 CT Connecticut Department of Publilc Health PH /30/2017 NY New York State Department of Health NELAP 04/1/2018 NH-S New Hampshire Environmental Lab 2516 NELAP 02/5/2018 RI Rhode Island Department of Health LAO /30/2017 NC North Carolina Div. of Water Quality /31/2017 NJ New Jersey DEP MA007 NELAP 06/30/2017 FL Florida Department of Health E NELAP 06/30/2018 VT Vermont Department of Health Lead Laboratory LL /30/2017 ME State of Maine /9/2019 VA Commonwealth of Virginia /14/2017 NH-P New Hampshire Environmental Lab 2557 NELAP 09/6/2017 VT-DW Vermont Department of Health Drinking Water VT /12/2018 Page 16 of 20

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