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Home My WebLink About23071_VEGA Metals_AWP_20230224 115 MacKenan Drive | Cary NC 27511 t: 919.469.3340 | www.withersravenel.com | License No. F‐1479 Asheville | Cary | Charlotte | Greensboro | Lumberton | Pittsboro | Raleigh | Southern Pines | Wilmington PROPOSED SUB‐SLAB VAPOR ASSESSMENT WORK PLAN THE VEGA 214 & 216 HUNT ST. DURHAM, DURHAM COUNTY, NORTH CAROLINA WithersRavenel Project #: 02191245.00 Brownfields Project #: 23071‐19‐032 Property Owner: Lambert Development Hunt Street II, LLC 5 Hanover Square 14th Floor New York, New York 10004‐2672 Prepared for: State of North Carolina Department of Environmental Quality Division of Waste Management Brownfields Redevelopment Section 1646 Mail Service Center Raleigh, North Carolina 27699‐1646 Prepared by: WithersRavenel 115 MacKenan Drive Cary, North Carolina 27511 North Carolina Firm License No. F‐1479 (Engineering) North Carolina Firm License No. C‐293 (Geology) February 24, 2023 The Vega WR Project No. 02191245.00 February 24, 2023 Page | 2 February 24, 2023 State of North Carolina Department of Environmental Quality Division of Waste Management Brownfields Program 1646 Mail Service Center Raleigh, North Carolina 27699‐1646 Attn: Ms. Claire Sorrell RE: Proposed Sub‐Slab Vapor Assessment Work Plan The Vega 214 & 216 Hunt Street, Durham, Durham County, North Carolina WR Project No. 02191245.00 Dear Ms. Sorrell, WithersRavenel is pleased to submit this proposed environmental site assessment work plan at the referenced site. We look forward to working with you on this project. Please feel free to contact us at (919) 469‐ 3340 with any questions and/or to discuss any aspect of the attached proposed work. Sincerely, WithersRavenel David Vail Environmental Scientist II G.Matthew James, P.G. Director of Geosciences R.S. (Butch) Lawter, Jr, P.E. Senior Delivery Officer The Vega WR Project No. 02191245.00 February 24, 2023 Page | 3 Lambert Development Hunt Street II, LLC 214 & 216 Hunt Street, Durham, Durham County, North Carolina Proposed Sub-Slab Vapor Assessment Work Plan Section 1. Introduction This proposed work plan is specific for “The Vega,” a seven story, ±150,770 square foot (ft2), mixed‐use structure located at 214 & 216 Hunt Street in the City of Durham, Durham County, North Carolina (Figure 1). The former onsite structure was demolished and removed prior to the construction of the current multi‐story onsite structure. A site map and a ground floor elevation map are provided as Figures 2 and 3, respectively. This work plan discusses the sub‐slab vapor assessment on the ±23,400 ft2 ground floor of the referenced structure. The ground floor consists of:  ±16,000 ft2 of parking,  ±600 ft2 of stairway / elevator space,  ±2,000 ft2 of resident storage space,  ±1,600 ft2 of lobby / mail room space,  ±700 ft2 of mechanical room space, and  ±2,500 ft2 of unfinished, future retail space. Note: The ±2,500 sq ft of unfinished, future retail space will be assessed at a later date, currently the space is not leased and therefore the floorplan is not finalized. WR will notify the Brownfields Redevelopment Section once a tenant and floorplan are finalized. This scope of work was negotiated during a January 20, 2023, call between WithersRavenel and NCDEQ Brownfields Redevelopment Section staff. 1.1 Site Location & Information The Vega redevelopment project has been accepted into the North Carolina Brownfields Program under project number 23071‐19‐032. The subject property has been redeveloped into a mixed‐ use multi‐story complex. When completely built‐out, the complex will consist of slab‐on‐grade ground floor parking with a residence lobby and commercial space (note: post‐tension slabs will not be used on this phase of construction). There will be no ground floor residential living spaces. The ground floor will also contain some community use areas, (i.e. mail room and storage lockers). The Vega project parcels have the following attributes according to the Durham County GIS website: The Vega WR Project No. 02191245.00 February 24, 2023 Page | 4 Parcel PIN No. Street Address Acreage Deed Date Deed Book Deed Page 0821‐98‐49‐ 4973 214 Hunt St 0.595 05/30/2019 8667 469 0821‐99‐30‐ 7582 216 Hunt St 0.012 05/30/2019 8667 469 Summary of Property History Based on information provided in the April 26, 2018, Phase I Environmental Site Assessment (ESA) for the subject property, the eastern portion of the property was utilized for residential purposes from 1907 through 1913. From 1937 through present a former onsite structure housed the following known occupants: • Carolina Motor Rebuilding, John H F Millwork, Vickers Motor Repairs, Young Roofing, Old North State Breweries Beer Distribution, Harris Garage Repairs, Avis Auto Rental, Yellow Cab Taxi Company, Broadway Cab Company, Checker Auto Sales, Vega Metals, and Cricket Forge. Since the construction of the former onsite structure in 1937 and removal of the former residential structures, the eastern portion of the property was never redeveloped and only used for parking. The following recognized environmental conditions (RECs) were reported in the April 26, 2018, Phase I ESA: • Historical use of the property as an auto repair, car rental and taxicab company. • Exposure of scrap metals to stormwater for a long period of time. • Two air compressors. • The sump and floor drain located onsite. • The sandblasting operation filtration system. • The closed‐in‐place underground storage tank (UST). • The hydraulic cylinder associated with the vehicle lift. Subsequent soil and groundwater investigations identified the following areas needing remediation: • Soils associated with former air compressor area; • Area of Arsenic soils exceeding Industrial / Commercial Health Preliminary Soil Remediation Goals (PSRGs). • Area of Lead and Arsenic in soil exceeding Industrial / Commercial Health PSRGs. • Removal of hydraulic lift and closed‐in‐place UST. Groundwater samples obtained from eight monitoring wells sampled in February 2020 did not reveal any volatile organic compounds (VOCs), semi‐volatile organic compounds (SVOCs) or RCRA‐8 metals elements at concentrations above 15A NCAC 02L .0202 Groundwater Quality Standards. Prior to implementation of the EMP, and with the knowledge and consent of DEQ Brownfields Section, the former onsite structure was demolished, and the building debris was disposed of by The Vega WR Project No. 02191245.00 February 24, 2023 Page | 5 others. Soil was not disturbed until the EMP was in place. After the EMP was approved in November 2020, the concrete slab was removed, soil was sampled, and other activities proceeded. All soil analytical results were compared to the NCDEQ regulatory standards in place at the time of sample collection. In April 2021, WR contracted EVO Corporation (EVO), as environmental remediation contractor, to perform remedial activities at the site consisting of the following: 1. Remediation of the former air compressor area: a. A total of 819.37 tons of petroleum impacted soil were removed from the excavation in this location. The final limits of the excavation measured 100‐feet (‐ft) east‐west by 15‐ft north‐south by 7‐ft to 12‐ft deep. The excavation was terminated when bedrock was encountered in the floor of the excavation. This work, as well as supporting documentation (maps, analytical results, certificates of disposal, and waste manifests were included in the Environmental Management Plan Report of Implementation dated February 2022 by WR). 2. Remediation of Arsenic soils exceeding Industrial / Commercial Health Preliminary Soil Remediation Goals (PSRGs): a. Per the EMP, the first 4‐ft of soil in the excavation identified as “Excavation 1” in the EMP Report of Implementation dated February 2022 by WR, was stockpiled adjacent to the excavation. Subsequently, an area between 4‐ft BGS to 12‐ft BGS was excavated. The excavation extended 15‐ft north‐south and 17‐ft east‐west. The excavated soils were placed in lined roll‐off boxes for sampling and the development of a disposal profile. A second excavation, identified as “Excavation 2” in the EMP Report of Implementation dated February 2022 by WR, was performed. Soils from this excavation were also placed in separate lined roll‐off boxes for sampling and the development of a disposal profile. Excavation 2 extended to a depth of 10‐ft BGS and extended 12‐ft east‐west and 10‐ft north‐ south. Per the analytical results, Waste Management’s Great Oaks Landfill in Randleman, NC accepted 195.45 tons of arsenic and lead impacted soils as non‐ hazardous waste. This work, as well as supporting documentation (maps, analytical results, certificates of disposal, and waste manifests were included in the Environmental Management Plan Report of Implementation dated February 2022 by WR). 3. Removal of hydraulic lift and closed‐in‐place UST a. Hydraulic Lift: WR oversaw the removal of an out‐of‐service hydraulic lift and associated reservoir. Following the removal of these items and associated concrete, WR oversaw the excavation of approximately 95 tons of petroleum impacted soils. The soils were live loaded and hauled to EVO’s permitted disposal facility in Winston‐Salem, NC. An area measuring 25‐ft east‐west by 13‐ft north‐south by 13‐ft deep was excavated. Analytical results indicated that arsenic concentrations in this area remained at levels exceeding the Industrial / Commercial MSCCs in the two post‐excavation samples. No other VOC, SVOC, or RCRA‐8 metal elements were identified at levels exceeding the Residential MSCCs. This work, as well as supporting documentation (maps, analytical results, certificates of disposal, and waste manifests were included in the Environmental Management Plan Report of Implementation dated February 2022 by WR). b. Closed‐in‐Place UST: WR oversaw the remediation of an approximately 6,000‐ gallon UST that had previously been closed‐in‐place by filling the UST with The Vega WR Project No. 02191245.00 February 24, 2023 Page | 6 concrete grout. The concrete grout was crushed, and 56.88 tons of petroleum impacted concrete was transported to the Waste Management’s Great Oaks Landfill in Randleman, NC. Following the removal of the UST and petroleum impacted concrete, approximately 75 tons of petroleum impacted soils were live loaded and hauled to EVO’s permitted disposal facility in Winston‐Salem, NC. The UST area excavation was advanced to bedrock at a depth of 13‐ft BGS. The final limits of the excavation measured 26‐ft north‐south by 15‐ft east‐west. Analytical results revealed that arsenic concentrations were present at levels that exceeded the Industrial / Commercial MSCCs in seven of the nine post‐excavation samples in this excavation. No other VOC, SVOC, or RCRA‐8 metal elements were identified at levels exceeding the Residential MSCCs. This work, as well as supporting documentation (maps, analytical results, certificates of disposal, and waste manifests were included in the Environmental Management Plan Report of Implementation dated February 2022 by WR). 4. Removal of non‐Load Bearing Soils a. Following the review of analytical results from the remedial efforts conducted in April 2021 and following the determination from the project geotechnical engineer that soils from the area of the former onsite structure were not geotechnically suitable to support the planned structure, the developer elected to have all the soil material from the “A” line to the “F” line on the construction drawings excavated and disposed of offsite. Based on the post remedial soil analytical results it was determined that the soils between the A and F lines should be disposed of at Republic Services’ Upper Piedmont Regional Landfill in Rougemont, NC. Prior to the removal of any soils, site analytical data was provided to Republic Services and disposal profile was established. b. Between July 9, 2021 and October 28, 2021, 2,786.98 tons of non‐load bearing soils were removed from the area between the A and F lines and transported to the Upper Piedmont Regional Landfill for disposal. The area was excavated to bedrock or to strata determined to be suitable for construction by the onsite geotechnical engineer. This work, as well as supporting documentation (maps, analytical results, certificates of disposal, and waste manifests were included in the Environmental Management Plan Report of Implementation dated February 2022 by WR). By completing the targeted removal of soils previously identified as “needing remediation” during the above‐described excavation activities in items one to three, and subsequently completing the mass grading of the site, including the removal of 2,786.98 tons of non‐load bearing soils with excavation activities extending to bedrock or suitable soils for construction, it is believed that all areas previously identified as “needing remediation” were effectively remediated. Historical site analytical data is included as Appendix A. Sampling of soil and groundwater did not identify chemicals of concern that typically cause vapor intrusion (VI) issues; however, for the protection of future occupants, the installation of a Vapor Intrusion Mitigation System (VIMS) was recommended as an engineering control to mitigate VI risk. The work proposed in this work plan is intended for use and review by the NCDEQ Brownfields Program and is not intended to be used by other NCDEQ departments. The Vega WR Project No. 02191245.00 February 24, 2023 Page | 7 Section 2. Scope of Work 2.1 Previously Completed Work WR designed a VIMS that was developed in general accordance with ANSI/AARST CC‐1000 guidelines and consists of a passive sub‐slab ventilation system in combination with a passive barrier that covers the entire footprint of the ground floor of the planned structure. The passive barrier consists of a Stego® Wrap 15‐Mil Vapor Barrier underlain by a 6‐inch (‐in) layer of washed stone. Four PVC type perforated pipes were bedded within the washed stone to facilitate sub‐slab gas removal, if needed. The perforated pipes were connected to 4‐in diameter trunk lines which passively collect sub‐slab vapor and will discharge the vapor through aluminum turbine ventilators mounted to the northern elevation of the planned structure. 2.2 Proposed Scope of Work The present scope of work for the project includes the installation of 11 sub‐slab VaporPins® in the building’s slab‐on‐grade. The majority of the ground floor of the building is reserved for parking but also includes a residence lobby, future commercial space, storage locker areas, a riser room, an electrical room, a switchgear and meter room, two structural staircases, and an elevator bank with two individual elevators. Nine of the eleven planned sub‐slab VaporPins® will be able to be installed at this phase of the project. The final floor in the west retail / commercial portion of the site has not been poured at this time. Sample locations are spread throughout the parking garage area, storage locker area, riser room, east retail/commercial area, west retail/commercial area, the two staircases, and the lobby area near (adjacent to the rear of the elevator bank per NCDEQ Brownfield direction). WR will utilize their in‐house Subsurface Utilities Engineering (SUE) group to locate all utilities below the slab prior to VaporPins® installation. Section 3. Sampling Methodology WR will perform site sampling activities in accordance with the NCDEQ Division of Waste Management Vapor Intrusion Guidance (March 2018, Version 2). WR will be installing and sampling 11 VaporPins® in the newly poured concrete slab at the site. Two of the VaporPins® will be located in the future retail area on the west end of the building. These two will be installed and sampled at a later date, after the that portion of the slab is poured and cured. All VaporPins® will be located at least 5‐ft away from exterior walls, slab penetrations, and control joints/cracks in the slab where possible. Following utility locating, WR will utilize a hammer drill to advance a 1.5‐in diameter hole in the surface of the slab to a depth of approximately 1.75‐in. A 5/8‐in diameter hole will then be advanced through the slab and vapor barrier below. The thickness of the slab is known to vary throughout the site and may be as thick as 18‐in in the structural staircases. WR will record the thickness of the slab and sub‐surface material encountered at each sample location. A nylon brush will then be used to clear the hole of any loose materials. A 3.5‐in long stainless steel VaporPin® sampling device will be fitted with a silicone VaporPin® sleeve and installed into the recessed 5/8‐in diameter hole using the manufacturer’s installation tool. After installation, each of the VaporPins® will be given a minimum of at least 20‐minutes for sub‐slab atmosphere stabilization per the manufacturer’s recommendation. The Vega WR Project No. 02191245.00 February 24, 2023 Page | 8 WR will check for a secure installation by placing a protective silicone VaporPin® cap over the ¼‐in diameter barbed fitting and performing a liquid leak test with a water dam. All VaporPins® will be secured with a flush‐mount stainless steel cover that can only be removed with a spanner screwdriver. WR will collect sub‐slab vapor samples at each of the eleven (nine to be collected in the initial sampling since the final floor in west retail/commercial space has not been poured) vapor sample points for laboratory analysis of VOCs by Method TO‐15. A full list of targeted compounds are provided as Appendix B. The sub‐slab samples will be collected in one‐liter, individually certified, laboratory supplied stainless steel summa canisters utilizing individually certified flow controllers. All sample locations will include a helium leak check. Dedicated Tygon tubing will be connected to the barbed fittings on the VaporPins®. Dedicated lengths of Teflon tubing will be connected to the Tygon tubing and attached to the dedicated laboratory provided flow controllers that connect to the summa cannisters. The flow controllers utilized will have a maximum sampling rate of 200 milliliters (ml) per minute, or five minutes for a one‐liter summa canister. Prior to sample collection, WR will purge each VaporPin® and sampling train with a dedicated 60mL syringe with Luer‐Lok Tip. A minimum of 300mL, or five full syringes, from the sampling train. Once all components of the sampling train are securely connected and purging of the VaporPin® is completed, WR will perform a shut‐in test for five minutes to check for any loss of pressure in the sampling train. Once WR verifies there is no loss in pressure, WR will perform a leak check using helium gas (laboratory grade) as a tracer. The leak check will be performed using a helium leak check kit provided by Eurofins Air Toxics. A shroud will be placed over the sampling point, sampling train, and connectors / fittings. Once helium is detectable at approximately 20% by volume within the shroud using the Kelron helium detection unit with integrated pump, WR will use a series of dedicated in‐line check valves to draw and direct air from the sampling point through the sampling train and flow controller and into the 60mL syringe. The vapor within the syringe will be transferred to a tedlar bag and measured using the Kelron helium detection unit. If helium gas is detected by the meter, but below 10% of the concentration within the shroud, a leak has not occurred per the DWM VI Guidelines, and a sample will be collected. If the helium concentration detected by the meter is greater than 10% of the helium concentration within the shroud, the sampling train connections will be checked/tightened and purged. This process will be repeated until helium levels are at or below the maximum acceptable levels. Prior to beginning sample collection, WR will record, on the chain‐of‐custody which regulators are being used with each of the summa canisters, the initial negative pressures in inches of Mercury (“Hg) in each summa canister prior to the beginning of sampling, and the negative pressure in “Hg remaining in the summa canister following the completion of the test. WR will record the remaining negative pressure in “Hg during the approximate mid‐point of the sampling period based on time in their field notes. It should be noted that various laboratories require different final pressures for analysis, but the typical range of negative pressure in “Hg at the completion of tests is five inches (5”) Hg. The VaporPin® sampling points will be capped with protective silicone covers on the barbed fittings after the completion of sampling and a stainless‐steel flush mount protective cover will be threaded onto the VaporPin® body to secure it. Since the VaporPins® provide a permanent, air‐ tight, flush‐mount, and secured seal, the VaporPins® will remain on the site indefinitely. Should the points need to be removed at any point, the VaporPins® will be extracted, and Stego® Mastic will be injected below and above the vapor barrier in accordance with the manufacturer’s The Vega WR Project No. 02191245.00 February 24, 2023 Page | 9 penetration sealing guidance. Concrete grout will then be mixed on site and poured directly onto the dry mastic in the base of the 5/8‐in diameter hole and in the cavity of the 1.5‐in x 1.75‐in hole at the surface of the slab. The grout will be finished at the surface of the slab‐on‐grade in a manner similar to the surrounding area. Any changes to the VIMS sampling points will be reviewed and approved by the resident engineer and the Brownfields Redevelopment Section will be notified by the engineer prior to any onsite work taking place. Mercury was included in historical soil and groundwater sampling activities conducted in April 2018 and in February 2020. Mercury was not detected above the laboratory’s method detection limit in groundwater samples collected on the site in April 2018 and again in February 2020. Mercury was detected in shallow soils (less than 6‐ft BGS) in one of the soil samples collected in April 2020 and in four of the soil samples collected in February 2020. None of the mercury concentrations in soil exceeded the NCDEQ Protection of Groundwater PSRG. Additionally, as reported in the February 22, 2022 Environmental Management Plan Implementation Report, no mercury was identified in soil samples collected following the removal of contaminated soils from the site. Based on the above data, mercury vapor is not considered a compound of concern at this site and is therefore not included in the VIMS monitoring plan. Section 4. Laboratory Analysis WR will submit the individually certified summa canister samples collected from the sub‐slab VaporPins® under proper chain of custody procedures for analysis by United States Environmental Protection Agency (USEPA) Method TO‐15 Low Level Analysis for Volatile Organic Compounds (VOCs) to Eurofins Air Toxics, LLC (Eurofins) located in Folsom, California. Eurofins’ modified TO‐15 Low Level analyte list and reporting limits are provided as Appendix B. The specified hold time for the samples is 30 days from collection. Indoor air interference is not anticipated to occur with the collection of these sub‐slab samples as leak detection will be performed prior to sampling and samples will be collected from below the slab. Eurofins holds NAICS Certification under code 541380 as well as certification under the National Environmental Laboratory Accreditation Program (NELAP / ELAP) for performing EPA TO‐15 sample analysis. Eurofins performs surrogate testing, Laboratory Blank analysis, Continuing Calibration Verification, Laboratory Control Sample, and a Laboratory Control Sample Duplicate as methods of Quality Assurance and Quality Control. The laboratory report will include J‐Flags and the reporting limits/method detection limits will meet applicable screening criteria (to the extent feasible). Section 5. Quality Assurance / Quality Control As less than 20 samples will be collected per media per method, one duplicate sample will be collected. A Trip Blank is not required and therefore will not be submitted for analysis. WR will collect samples in one‐liter stainless steel summa canisters, which is standard for this type of sub‐ slab sampling. The laboratory will include surrogate inclusions in the samples to ensure that recovery is within tolerable/acceptable ranges. All samples and pertinent information will be included on the chain of custody submitted with the samples to the laboratory. WR will affix initialed chain of custody stickers to the closed shipping box so that the integrity of the samples will be maintained during shipping of samples. The Vega WR Project No. 02191245.00 February 24, 2023 Page | 10 Section 6. Investigation Derived Waste Management WR does not anticipate generating Investigation Derived Waste (IWD) that will need to be containerized and disposed of in accordance with any regulations. The anticipated IWD from this site includes concrete cuttings as a result of using a hammer drill for the installation of the VaporPins®. The cuttings will be captured with a shop‐van equipped with a HEPA filter as they are generated to prevent any dust from migrating out of the work area. Section 7. Reporting All site activities including utility locating, VaporPin® installation procedures, leak check procedures, sample collection, photographic record of completed and uncompleted portions of ground floor, laboratory report with chain of custody and shipping procedures will be documented in a summary report. The report will include figures depicting the general site location, accurate sample locations, and a summary of sub‐slab vapor analytical results (see Appendix C for example). The maximum concentration of each analyte will be input into the NCDEQ Risk Calculator to establish Risk Levels for the site. The report will be signed and sealed by a Professional Geologist and/or a Professional Engineer. WithersRavenel is licensed to practice geology and engineering in the State of North Carolina. WR plans to implement this work plan immediately following Brownfields Program approval. Cordially, WithersRavenel David Vail Environmental Scientist II G. Matthew James, P.G. Director of Geosciences R.S. (Butch) Lawter, Jr, P.E. Senior Delivery Officer Enclosure(s): Figures Appendix A – Historical Site Analytical Data Appendix B – Eurofins modified TO‐15 Low Level analyte list and reporting limits Appendix C – Example Sub‐Slab Data Table DCV GMJ DRAWN BY: 01/26/23 02191245.00 1 SCALE:FIGURE NO.: PROJECT NO.:DATE:APPROVED BY: THE VEGA 214 & 216 HUNT STDURHAM, DURHAM COUNTY, NC GENERAL LOCATION MAP 1"=1000 ' GRAPHIC SCALE 1 inch = 1000 ft. 0 1000500 2000 WithersRavenel Engineers | Planners | Surveyors 115 MacKenan Drive | Cary, NC 27511 | t: 919.469.3340 | license #: F-1479www.withersravenel.com SUBJECT SITE ± 0.607 ACRES K:\19\19-1240\191245-Lambert Development - Vega Metals\Enviro\Background and Proposal\2023.01-VIMS_Pressure Test and Sampling\VEGA_BASE-VAPOR_SAMPLING.dwg- January 26, 2023 - DVAIL © 2023 Microsoft Corporation © 2022 Maxar ©CNES (2022) Distribution Airbus DS SB-2 SB-5 SB-10 SB-6SB-3 SB-4 SB-7SB-8 SB-9 TW-1 TW-2 TW-9 TW-1TW-3 TW-2TW-4 TW-5 TW-6 TW-7 TW-8 HUNT STREET RIGSBEE AVENUETHE VEGA VP-11 VP-7 VP-8 VP-6 VP-3 VP-5 VP-4 VP-2 VP-1VP-9 VP-10 DCVGMJDRAWN BY:01/26/2302191245.001SCALE:FIGURE NO.:PROJECT NO.:DATE:APPROVED BY:SITE MAPWithersRavenelEngineers | Planners | Surveyors115 MacKenan Drive | Cary, NC 27511 | t: 919.469.3340license #: F-1479 | www.withersravenel.comK:\19\19-1240\191245-Lambert Development - Vega Metals\Enviro\Background and Proposal\2023.01-VIMS_Pressure Test and Sampling\VEGA_BASE-VAPOR_SAMPLING.dwg- January 26, 2023 - DVAIL1"=30 'GRAPHIC SCALE 1 inch = 30 ft. 3015 600 LEGEND TEMPORARY MONITORING WELL &SOIL BORING LOCATION (WR - 2020) TEMPORARY MONITORING WELL LOCATION (S&ME - 2018) SOIL BORING LOCATION (S&ME - 2018) PROPOSED SUB-SLAB VAPOR SAMPLE LOCATION (WR - 2023) NOTES: 1.) AERIAL OBTAINED FROM THE LOCAL COUNTY GIS DEPARTMENT.THE VEGA214 & 216 HUNT STDURHAM, DURHAM COUNTY, NC UP UP 855 SF LOBBY P101 ELEV. 218 SF RISER RM. P108 494 SF EASTRETAIL/COMMERCIAL P107251 SF MAIL/PARCEL P102 309 SF ELECTRICAL SWITCHGEAR & METERS P105 WEST RETAIL/COMMERCIAL P104 P1 PARKING P103 16497 SF STORAGE P106 S1 S1 S1 S1 S1 S1 S1S2 105 104B 103 EXIT P109 STAIR 2 P1S2 STAIR 1 P1S1 101 1S1 108 104C 109 103A S1S1S1S1S1S1S1S1S1S1 S1 S1 S1 S1 S1 S1 S1 S1 S1 S1 S1 S1 S1 S1 S1 S1 S1 S1 VP-11 VP-10 VP-8 VP-6 VP-3 VP-4 VP-1 VP-2 VP-5 VP-7 VP-9 INSTALL CAST IRON RISER ABOVE GRADE. INSTALL APPROPRIATE TRANSITIONFITTINGS BETWEEN PVC AND CAST IRON. TURBINE VENTILATORS TO BE EMPIRE MODEL #TV04A (OR SIMILAR) MOUNTED TO EXTERIOR WALL BELOW P1 EXHAUST FAN. VAPOR PIN MONITORING/SAMPLING LOCATION (TYP. ) LEAVE 12X12" FORMED UNPOURED OPENING TOALLOW FOR FUTURE INSTALLATION OF VAPOR PIN SAMPLING LOCATIONS. CONTRACTOR TO COORDINATEWITH ENVIRONMENTAL CONSULTANT TO SEAL VAPOR BARRIER AFTER SAMPLE PROBE AND TUBINGPLACEMENT, AND COMPLETE INSTALLATION OF SAMPLE MANHOLE COVER. (SEE DETAIL 1) 4" PERFORATED PVC PIPE CONSTRUCTED WITH APPROPRIATE4" FITTINGS TYP. 1 2 3 4 5 A C D E F G H J K B INSTALL PVC RISER BELOW GRADE AND CAST IRON RISER ABOVE GRADE.INSTALL APPROPRIATE TRANSITION FITTINGS BETWEEN PVC AND CASTIRON. TURBINE VENTILATOR TO BE MOUNTED TO EXTERIOR WALL. No. Checked By Revision Designer Drawn By Date By Scale Date Job No. Sheet No.WithersRavenel $ngineers . /lanners [ STrveyors 115 MacKenan Drive | Cary, NC 27511 | t: 919.469.3340 | license #: C-0832 |www.withersravenel.com VAPOR MITIGATION PLAN VEGA METALS PROPERTY DURHAM, DURHAM COUNTY, NORTH CAROLINA SUB-SLAB VENT LINE AND VAPOR PIN LOCATIONS 1 GMJ GMJ RSL 02191245.00 03/18/2021 AS-SHOWN GENERAL NOTES 1.) SUB-SLAB VAPOR VENT LINES TO BE CONSTRUCTED OF 4-INCH DIAMETER PVC PERFORATED PIPE. 2.) ALL VENT LINE JOINTS AND CONNECTIONS TO BE SECURED WITH STEGO MANUFACTURE ADHESIVE TAPE. SEE MANUFACTURER'S INSTALLATION GUIDANCE DOCUMENTS. 3.) MITIGATION CONTRACTOR TO PLACE PIPE MARKERS SPECIFYING PIPING IS ASSOCIATED WITH VAPOR MITIGATION: MAXIMUM OF 15 FOOT SEPARATION BETWEEN MARKERS. 4.) VAPOR PINS TO BE INSTALLED POST CONSTRUCTION FOR MONITORING OF SUB-SLAB VAPOR (BY OTHERS). 5.) SUB-SLAB VAPOR VENT DISCHARGE TO BE FINISHED WITH 4-INCH ALUMINUM TURBINE VENTILATOR OR SIMILAR. EXHAUST AIR TO BE DISCHARGE A MINIMUM OF 10 FEET FROM ANY AIR IN TAKE. 6.) SEE SHEETS 3, 4, 5 FOR MANUFACTURER'S INSTALLATION GUIDELINES FOR SECURING BARRIER TO EXTERIOR FOUNDATION WALLS, COLUMNS, PIPE PENETRATIONS, WALLS, ETC... 7.) SEE VAPOR INTRUSION MITIGATION SYSTEM DESIGN DOCUMENT FOR MANUFACTURER'S PROVIDED INSTALLATION INSTRUCTIONS. 8.) PERFORATED PVC SHALL BE INSTALLED WITH PERFORATIONS FACING DOWNWARD TO ALLOW FOR MAXIMUM VAPOR COLLECTION. NOTE: PROPOSED STRUCTURES SHOWN HEREON FROM MHAworks SHEET NUMBER A100. NOT FOR CONSTRUCTIONNOT TO SCALE APPENDIX A EPA Method 1664B Area of Concern (AOC) Sample ID Sample Depth (ft-bgs) Date Collected 2 SB-2 9-11 4/16/2018 <0.00025 <0.00025 <0.00024 <0.00018 <0.0002 <0.00018 <0.00017 <0.00015 <0.00053 <0.013 <0.00016 <0.00018 <0.00014 <0.00025 <0.00012 <0.00017 <0.00088 <0.00022 <0.00052 <0.023 <0.013 <0.014 <0.012 <0.014 <1.7 -- -- 3 SB-3 0-2 4/16/2018 <0.00027 <0.00027 <0.00026 <0.0002 <0.00022 <0.0002 <0.00018 <0.00016 <0.00057 <0.014 <0.00017 <0.0002 <0.00015 <0.00027 <0.00013 <0.00018 <0.00095 <0.00024 <0.00056 <0.027 <0.015 <0.016 <0.014 <0.016 ----685 4 SB-4* 2.5-5 4/16/2018 0.079 J 0.34 <0.026 <0.02 0.061 J 0.11 <0.018 <0.016 <0.056 <1.4 <0.017 <0.020 <0.015 <0.027 <0.013 <0.018 <0.093 <0.024 <0.055 <0.026 <0.014 0.058 <0.013 <0.015 ---- <58.2 5 SB-5 0-2 4/16/2018 <0.0029 <0.00029 <0.00028 <0.00022 <0.00024 <0.00022 <0.0002 <0.00017 <0.00062 <0.015 <0.00018 <0.00022 <0.00016 <0.00029 <0.00014 <0.0002 <0.001 <0.00026 <0.00061 -- -- -- -- -- ----306 6 SB-6 0-2 4/16/2018 <0.00027 <0.00027 <0.00026 <0.0002 <0.00022 <0.0002 <0.00018 <0.00016 <0.00056 <0.014 <0.00017 <0.0002 <0.00015 <0.00027 <0.00013 <0.00018 <0.00094 <0.00024 <0.00055 -- -- -- -- -- ---- -- 7 SB-7 0-2.5 4/16/2018 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- ---- -- 8 SB-8 2.5-5 4/16/2018 0.04 <0.00031 0.00067 J 0.014 <0.00025 <0.00023 <0.0002 0.0007 J <0.00064 <0.016 0.00097 J 0.0036 0.0028 0.018 0.0034 0.0043 <0.0011 <0.00027 0.015 -- -- -- -- -- ----1,030 9 SB-9 5-7.5 4/16/2018 0.078 <0.00029 0.0019 0.11 <0.00024 <0.00021 0.019 0.012 0.032 0.02 J 0.0048 0.028 0.012 0.011 0.027 0.023 0.0066 0.0023 0.077 0.19 0.048 0.053 0.088 0.092 ---- -- 10 SB-10 4-6 4/16/2018 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- <0.025 <0.014 <0.015 <0.012 <0.015 -- <1.9 -- 4.1 0.39 0.004 11 3.8 0.12 2 1.24 NE 25 0.01 13 2.3 0.39 4.5 2.6 4.1 8.3 9.9 0.11 0.35 670 134 440 50** 100** 250** 12 380 2.6 56 NE 2.8 310 NE 11,000 12,000 1.2 6.1 410 4.1 780 780 1,600 990 120 18 1.1 480 NE 360 NE NE NE 55 2,000 12 320 NE 12 4,700 NE 48,000 140,000 5.4 27 2,100 180 12,000 5,100 23,000 9,700 530 73 21 6,000 NE 4,500 NE NE NE 2.6 0.23 0.003 8 7.6 0.099 0.1 0.12 0.4 24 0.0056 4.9 1.7 0.16 4.3 1.7 3.3 4.3 4.6 0.04 0.35 290 56 270 NE NE NE 156 1,400 10 782 460 110 1,000 100 1,200 14,000 18 1,560 1,564 313 626 626 626 1,200 3,129 20 0.88 620 469 469 NE NE NE 4,088 36,000 92 20,440 12,000 1,000 20,000 4,000 32,000 360,000 164 40,000 40,880 8,176 16,350 16,350 16,350 32,000 81,760 100 8 16,400 12,264 12,264 NE NE NE Notes: Analytes that are not shown for the method were not detected. Concentrations are reported in milligrams per kilograms (mg/Kg). SB-4*: Reporting limits are elevated in the results reported for SB-4, due to the sample being ran at a dilution by the laboratory. ND: Not Detected above the laboratory's practical quantitation limits. --: Not analyzed for the method shown. NE: Regulatory Level not established for compound. J indicates an estimated concentration. PSRGs - North Carolina Department of Environmental Quality Preliminary Soil Remediation Goals (February 2018). MSCCs - Maximum Soil Contaminant Concentrations for Assessment and Corrective Action (April 2012). Concentrations shown in BOLD exceed the laboratory's reporting limits. Concentrations shown in BOLD and shaded exceed the protection of groundwater PSRGs and/or the soil-to-water MSCCs. ** = North Carolina Action Levels 4-Methyl-2-pentanone1,2,4-Trichlorobenzene1,2-Dichlorobenzene1,3-DichlorobenzeneSemi-Volatile Organic Compounds by EPA Method 8270D 1-MethylnaphthaleneNaphthalenen-Butyl benzenen-Propyl benzeneXylenes (Total)Sec-butylbenzeneTolueneVolatile Organic Compounds by EPA Method 8260B Benzo(a)anthraceneFluoranthenePhenanthrenePyrene1,4-Dichlorobenzene1,2-DichloropropaneIsopropylbenzeneIndustrial/Commercial MSCCs Soil-to-Water MSCCs Residential MSCCs Analytical Method → Detected Analytes → Residential Health Based PSRGs Industrial/Commercial Health Based PSRGs Protection of Groundwater PSRGs Total Petroleum Hydrocarbons by EPA Method 8015C Gasoline Range Organics(GRO)Diesel Range Organics (DRO)Oil and Grease TABLE 2 SUMMARY OF SOIL ANALYTICAL RESULTS -ORGANIC CONSTITUENTS 214 and 216 Hunt Street Durham, Durham County, North Carolina S&ME Project No. 4305-18-083 1,3,5-Trimethylbenzene4-IsopropyltolueneBenzeneEthylbenzene2-ChlorotolueneAcetoneT:\Projects\2018\ENV\4305-18-083 214_216 Hunt Street Phase I ESA Limited Soil GW Sampling\Working_Documents\Limited Soil-GW Assessment\Tables\214 Hunt St Phase II Tables.xlsx EPA Method 7470A Area of Concern (AOC) Sample ID Sample Depth (ft-bgs) Date Collected 2 SB-2 9-11 4/16/2018 3.57*128 18.9*6.53 <0.803 <0.0346 3 SB-3 0-2 4/16/2018 8.29*188 26*12.5 5.75 <0.0387 4 SB-4 2.5-5 4/16/2018 3.1*49.7 15.7*5.3 <1.04 <0.0405 5 SB-5 0-2 4/16/2018 ------------ 6 SB-6 0-2 4/16/2018 1.76 73.3 9*17.9 <0.932 0.0893 7 SB-7 0-2.5 4/16/2018 2.8 58.6 15.8*7.2 <0.903 <0.0398 8 SB-8 2.5-5 4/16/2018 ------------ 9 SB-9 5-7.5 4/16/2018 1.62 44.8 11.9*12.9 <0.657 <0.0414 10 SB-10 4-6 4/16/2018 ------------ 5.8 580 3.8 270 2.1 1 0.68 3,100 0.31 NE 78 2.3 3 47,000 6.5 NE 1,200 9.7 NE 290 5.4 270 NE NE NE 3,100 47 400 NE NE NE 81,000 1,226 400 NE NE Notes: Analytes that are not shown for the method were not detected. Concentrations are reported in milligrams per kilograms (mg/Kg). ND: Not Detected above the laboratory's practical quantitation limits. --: Not analyzed for the method shown. NE: Regulatory Level not established for compound. J indicates an estimated concentration. PSRGs - North Carolina Department of Environmental Quality Preliminary Soil Remediation Goals (February 2018). MSCCs - Maximum Soil Contaminant Concentrations for Assessment and Corrective Action (April 2012). Concentrations shown in BOLD exceed the laboratory's reporting limits. Concentrations shown in BOLD and shaded exceed the protection of groundwater PSRGs and/or the soil-to-water MSCCs. Concentrations shown in BOLD and underlined exceed the residential health based PSRGs or residential MSCCs. Concentrations shown in BOLD, underlined, and with a * exceed the industrial/commercial health based PSRGs or industrial/commercial MSCCS TABLE 3 SUMMARY OF SOIL ANALYTICAL RESULTS - INORGANIC CONSTITUENTS 214 and 216 Hunt Street Durham, Durham County, North Carolina S&ME Project No. 4305-18-083 Industrial/Commercial Health Based PSRGs Detected Analytes →BariumMetals by EPA Method 6010DAnalytical Method →MercuryChromiumLeadResidential MSCCs Industrial/Commercial MSCCs ArsenicSoil-to-Water MSCCs SeleniumProtection of Groundwater PSRGs Residential Health Based PSRGs T:\Projects\2018\ENV\4305-18-083 214_216 Hunt Street Phase I ESA Limited Soil GW Sampling\Working_Documents\Limited Soil-GW Assessment\Tables\214 Hunt St Phase II Tables.xlsx Well ID Date Installed Total Well Depth (ft-BTOC) Total Well Depth (ft-bgs) Screened Interval (ft-bgs) Stickup Height (ft-GRD) Date Water Level Measured Depth to Water (ft-bgs) Depth to Water (ft-BTOC) TW-1 4/17/2018 22.3 22 22 - 7 0.3 4/18/2018 7.07 7.37 TW-2 4/16/2018 10.25 9.35 9.35 - 4.35 0.9 4/17/2018 4.51 5.41 TW-9 4/16/2018 15.35 14.35 14.35 - 4.35 1.0 4/17/2018 12.46 13.46 NOTES: ft-BTOC: feet below top of casing ft-bgs: feet below ground surface ft-GRD: feet above ground surface ft-rel: feet relative Temporary wells TW-1, TW-2, and TW-3 were abandoned after sampling. TABLE 4 DEPTH TO WATER & TEMPORARY WELL CONSTRUCTION 214 and 216 Hunt Street Durham, Durham County, North Carolina S&ME Project No. 4305-18-083 Temporary wells were in stalled in a low yielding formation, and no groundwater was observed during the drilling/well installation. Water levels were measured the day following well installation, however, water levels may not have completely equilibrated. T:\Projects\2018\ENV\4305-18-083 214_216 Hunt Street Phase I ESA Limited Soil GW Sampling\Working_Documents\Limited Soil-GW Assessment\Tables\214 Hunt St Phase II Tables.xlsx EPA Method 7470A Area of Concern (AOC) Sample ID Date Collected 1 TW-1 4/18/2018 <0.10 <0.30 <10 -- -- -- 2 TW-2 4/17/2018 <0.10 <0.30 <10 153 10.4 <0.15 9 TW-9 4/17/2018 0.69 J 0.48 J 30 214 9.67 J <0.15 400 400 6,000 700 10 1 28,500 25,000 6,000,000 700,000 10,000 NE 50 35 4,500,000 NE NE 0.18 210 150 19,000,000 NE NE 0.75 Notes: Analytes that are not shown for the method were not detected. Concentrations are reported in micrograms per liter (µg/L). ND: Not Detected above the laboratory's practical quantitation limits. --: Not analyzed for the method shown. NE: Regulatory Level not established for compound. J indicates an estimated concentration. 2L Standard: North Carolina Groundwater Quality Standards: 15A NCAC 2L.0202 GWSL: Vapor Intrusion Screening Level - Groundwater Screening Level (February 2018) Concentrations shown inBOLD exceed the laboratory's reporting limits. Concentrations shown inBOLD and shaded exceed the 2L Standard. Non-Residential GWSL Constituent Specific Volatile Organic Compounds by EPA Method 8260B MercuryNo constituents detected No constituents detected No constituents detected 2L Standard Residential GWSL Gross Contaminant Level EPA Method 8270D Semi-Volatile OrganicCompoundsTABLE 5 SUMMARY OF GROUNDWATER ANALYTICAL RESULTS AcetoneDetected Analytes →1,2,4-Trimethylbenzene1,3,5-Trimethylbenzene214 and 216 Hunt Street Durham, Durham County, North Carolina S&ME Project No. 4305-18-083 Metals by EPA Method 6010D (µg/L)BariumChromiumAnalytical Method → T:\Projects\2018\ENV\4305-18-083 214_216 Hunt Street Phase I ESA Limited Soil GW Sampling\Working_Documents\Limited Soil-GW Assessment\Tables\214 Hunt St Phase II Tables.xlsx Easting NorthingTW-1 02/20/2020 1 20.0 0-10 10-20 NM 02/24/2020 17.43---NM 2029544.9497 819024.1969TW-2 02/20/2020 1 20.0 0-10 10-20 NM 02/24/2020 16.56---NM 2029543.1174 818968.7451TW-3 02/20/2020 1 10.0 0-5 5-10 NM 02/24/2020 DRY---NM 2029463.1193 819023.3810TW-4 02/24/2020 1 10.0 0-5 5-10 NM 02/25/2020 DRY---NM 2029463.9630 818969.3941TW-5 02/24/2020 1 20.0 0-10 10-20 NM 02/24/2020 7.19---NM 2029392.4902 819011.3265TW-6 02/24/2020 1 20.0 0-10 10-20 NM 02/24/2020 7.09---NM 2029393.0059 818971.3779TW-7 02/24/2020 1 20.0 0-10 10-20 NM 02/25/2020 4.83---NM 2029349.9790 819008.2734TW-8 02/25/2020 1 20.0 0-10 10-20 NM 02/25/2020 4.47---NM 2029351.0632 818968.4080Table 1214 & 216 Hunt StreetMonitoring & Remediation Well Construction InformationWell Casing Diameter(inches)Free Product Thickness(feet)Screened Interval (feet)Top-of-Casing Elevation (feet)Well Casing Depth (feet)Lambert Development Hunt Street II, LLCDurham, Durham County, North CarolinaDate InstalledGroundwaterElevation (feet)WR Project Number: 02191245.00Well IDWell Coordinates(NC State Plane NAD 83 Feet)Depth-to-Water from Top-of-Casing(feet)Notes: 1.) NM = Not MeasuredTotal Depth (feet)Date Water Level MeasuredPage 1 of 1 SOIL SAMPLE ID DATE SAMPLE DEPTH (feet BLS) TPH/GRO (mg/kg) TPH/DRO (mg/kg) SB‐1 2/20/2020 2‐4 BDL BDL SB‐1 2/20/2020 6‐8 BDL 3.7 SB‐1 2/20/2020 12‐14 BDL 3.7 SB‐1 2/20/2020 16‐19 BDL 5.4 SB‐2 2/20/2020 2‐4 BDL 5.9 SB‐2 2/20/2020 5‐6 BDL BDL SB‐2 2/20/2020 10‐12 BDL 8.4 SB‐2 2/20/2020 15‐16 BDL BDL SB‐3 2/20/2020 2‐4 BDL BDL SB‐3 2/20/2020 8‐10 BDL 8.3 SB‐4 2/24/2020 2‐4 BDL 15 SB‐4 2/24/2020 8‐10 BDL 4.1 SB‐5 2/24/2020 2‐4 BDL BDL SB‐5 2/24/2020 8‐10 BDL 20 SB‐5 2/24/2020 12‐14 BDL 50 SB‐6 2/24/2020 3‐5 BDL BDL SB‐6 2/24/2020 8‐10 BDL 15 SB‐6 2/24/2020 18‐20 BDL 70 SB‐7 2/24/2020 2‐4 BDL 20 SB‐7 2/24/2020 8‐10 BDL BDL SB‐7 2/24/2020 16‐20 BDL 17 SB‐8 2/25/2020 2‐4 BDL 13 SB‐8 2/25/2020 8‐10 BDL 8.6 SB‐8 2/25/2020 18‐20 33 3.6 Notes: 1 ‐ N/A = Not Applicable or Sampled 2 ‐ Results in bold exceed laboratory detection limits. 3 ‐ Results shaded bold exceed the NCDEQ action level. 4 ‐ BLS = Below Land Surface. 5 ‐ Results are in mg/kg (milligrams per kilogram). 6 ‐ Soil samples were collected February 20 & 24‐25, 2020. 7 ‐ TPH = Total Petroleum Hydrocarbons 8 ‐ BDL = Below Detection Limits Lambert Development Hunt Street II, LLC 9 ‐ GRO = Gasoline Range Organics 10 ‐ DRO = Diesel Range Organics Table 2A Summary of Soil Analytical Results (TPH) 214 & 216 Hunt Street Durham, Durham County, North Carolina WR Project Number: 02191245.00 NCDEQ Action Levels 50 100 9071BAcetoneBenzeneSec-ButylbenzeneIsopropylbenzeneMethylene ChlorideN-PropylbenzeneTolueneRemaining Targeted VOCsBenzo(a)anthraceneBenzo(b)fluorantheneBenzo(k)fluorantheneBenzo(a)pyreneChryseneFluoranthenePhenanthrenePyreneRemaining Targeted SVOCsArsenicBariumCadmiumTotal ChromiumHexavalent ChromiumLeadMercurySeleniumSilverOil & Grease67-64-1 71-43-2 135-98-8 98-82-8 75-09-2 103-65-1 108-88-3---56-55-3 205-99-2 207-08-9 50-32-8 218-01-9 206-44-0 85-01-8 129-00-0---7440-38-2 7440-39-3 7440-43-9 7440-47-3 18540-2-99 7439-92-1 7439-97-6 7782-49-2 7440-22-4 C-0007SB-1 (2'-4') 2/20/2020BDL BDL BDL BDL0.0037BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDL0.494 20.1 0.0165 6.85BDL6.29BDL BDL BDL BDLSB-1 (6'-8') 2/20/2020BDL BDL BDL BDL0.0032BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDL1.79 62.6 0.0263 5.5BDL4.69BDL BDL BDL BDLSB-1 (12'-14') 2/20/2020BDL BDL BDL BDL0.0029BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDLBDL66.5 0.0194 6.34BDL7.16BDL BDL BDL BDLSB-1 (16'-19') 2/20/2020BDL BDL BDL BDL0.0027BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDL0.855 372 0.0652 23.1BDL20.6BDL BDL BDL BDLSB-2 (2'-4') 2/20/2020BDL BDL BDL BDL0.0023BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDLBDL70.1BDL8.58 0.37 6.75BDL BDL BDL BDLSB-2 (5'-6') 2/20/2020BDL BDL BDL BDL0.0033BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDL2 67.6BDL8.53BDL2.69BDL BDL BDL62.9SB-2 (10'-12') 2/20/2020BDL BDL BDL BDL0.0027BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDL1.33 267 0.0146 27.1BDL19.2BDL BDL BDL BDLSB-2 (15'-16') 2/20/2020BDL BDL BDL BDL0.0026BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDL0.941 236BDL22.9BDL11.7BDL BDL BDL BDLSB-3 (2'-4') 2/20/2020BDLBDL BDL BDL0.0026BDL BDLBDLBDLBDL BDL BDL BDL BDL BDL BDLBDLBDL112BDL28.4BDL14.3BDL BDL BDL171SB-3 (8'-10') 2/20/2020BDL BDL BDL BDL0.0028BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDL1.62 215BDL26.7BDL13BDL BDL BDL BDLSB-4 (2'-4') 2/24/2020BDL0.00067BDL BDL0.0041BDL0.00053BDL0.078 0.13 0.049 0.092 0.083 0.16 0.055 0.14BDL5.73608 1.87 18.5BDL9950.115BDL BDL113SB-4 (8'-10') 2/24/2020BDL BDL BDL BDL0.0032BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDLBDL153 0.604 29.5BDL12.2BDL BDL BDL BDLSB-5 (2'-4') 2/24/2020BDL BDL BDL BDL0.0039BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDLBDL99.4 0.636 27.1BDL10.9BDL BDL BDL BDLSB-5 (8'-10') 2/24/2020BDL BDL BDL BDL0.0039BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDL0.659 105 0.348 18.7BDL11.1BDL BDL BDL BDLSB-5 (12'-14') 2/24/2020BDL BDL BDL BDL0.0033BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDLBDL51.4BDL13.3BDL25.3BDL BDL BDL BDLSB-6 (3'-5') 2/24/2020 0.013BDL BDL BDL0.0031BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDLBDL72.1 0.384 22.8BDL19.1 0.0765BDL BDL BDLSB-6 (8'-10') 2/24/2020BDL BDL BDL BDL0.0028BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDL0.949 462 0.544 27.2BDL13.6BDL BDL BDL BDLSB-6 (18'-20') 2/24/2020BDL BDL BDL BDL0.0033BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDLBDL78.9 0.426 85.5 0.21 5.83BDL BDL BDL BDLSB-7 (2'-4') 2/24/2020BDL BDL BDL BDL BDL BDL BDLBDL0.062 0.088BDL0.069 0.067 0.15 0.067 0.14BDL1.06 96 0.399 20.3 0.59 45.6 0.503BDL BDL136SB-7 (8'-10') 2/24/2020BDL BDL BDL BDL0.0024BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDL14179 0.743 28.6BDL10BDL BDL BDL194SB-7 (16'-20') 2/24/2020BDL BDL BDL BDL0.0026BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDL0.683 123 0.335 37.1BDL8.16BDL BDL BDL72.3SB-8 (2'-4') 2/25/2020BDL BDL BDL BDL0.002BDL BDLBDL0.045 0.074BDL0.054 0.053 0.12BDL0.1BDLBDL102BDL10.4BDL27.9 0.204BDL BDL BDLSB-8 (8'-10') 2/25/2020 0.015BDL0.0058 0.0014 0.0021 0.0038BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDLBDL61.8 0.27 13 0.26 18.7BDL BDL BDL BDLSB-8 (18'-20') 2/25/2020 0.012BDL BDL BDL0.0028BDL BDLBDLBDL BDL BDL BDL BDL BDL BDL BDLBDL32.7305 0.557 33.4BDL9.55BDL BDL BDL BDL25 0.01 4.1 2.3 0.025 2.6 8.3---0.35 1.2 12 0.12 36 670 134 440---5.8 580 3 360000 3.8 270 1 2.1 3.4 NL140,000 5.4 23,000 2,100 650 5,100 9,700---21 21 210 2.1 2,100 6,000 NL 4,500---3 47,000 200 350,000 6.5 800 9.7 1,200 1,200 NLNotes:1.) All results provided in mg/kg (milligrams per kilograms)3.) Protection of Groundwater PSRG - North Carolina Department of Environmental Quality Protection of Groundwater Preliminary Soil Remediation Goal (December 2019)4.) Industrial/ Commercial Health PSRG - North Carolina Department of Environmental Quality Industrial/ Commercial Health Preliminary Soil Remediation Goal (December 2019)NL= Not ListedNA= Compound Not Analyzed for by Laboratory.BDL= Below Detection Limits.Result= Result Exceeds Laboratory Detection LimitsResult= Result Exceeds Protection of Groundwater PSRGResult= Result Exceeds Industrial/Commercial Health PSRGIndustrial/ Commercial Health PSRG2.) Compounds analyzed for by laboratory but not listed were not detected above laboratory detection limits. See the laboratory report included in the Appendix for a full list of constituents. 8270D - Semi-Volatile Organic Compounds6000/7000 Series Metals8260B - Volatile Organic CompoundsAnalytical MethodSampleIDDateCollectedProtection of Groundwater PSRGDurham, Durham County, North CarolinaTable 2BSummary of Soil Analytical Results (VOCs, SVOCs, Metals, & O&G)Lambert Development Hunt Street II, LLCWR Project Number: 02191245.00214 & 216 Hunt StreetPage 1 of 1 Methyl tert-butyl ether (MTBE)Remaining Targeted VOCsAll Targeted SVOCsArsenicBariumCadmiumChromiumLeadMercurySeleniumSilver1634-04-4--- ---7440-38-2 7440-39-3 7440-43-9 7440-47-3 7439-92-1 7439-97-6 7782-49-2 7440-22-4TW-1 2/24/2020BDLBDL BDLBDL120BDL BDL6.31BDL BDL BDLTW-2 2/24/2020BDLBDL BDLBDL159BDL BDL BDL BDL BDL BDLTW-5 2/24/2020BDLBDL BDLBDL136BDL BDL BDL BDL BDL BDLTW-6 2/24/2020 0.93BDL BDLBDL113BDL BDL5.13BDL BDL BDLTW-7 2/25/2020BDLBDL BDLBDL123BDL BDL3.14BDL BDL BDLTW-8 2/25/2020BDLBDL BDLBDL120BDL BDL3.58BDL BDL BDL20------10700210151202020,000------NL 700,000 NL 10,000 15,000 NLNL 20,000Notes:1.) All results provided in ug/L (micrograms per liter) or parts per billion2.) Compounds analyzed by laboratory but not listed were not detected above laboratory detection limits. See the laboratory report included in the Appendix for a full list of constituents. 3.) NC 2L Standard - North Carolina Groundwater Quality Standard as per NC Administrative Code 15A NCAC 02L4.) GCLs for Groundwater = NCDENR UST Section Gross Contamination Levels for GroundwaterNL= Not ListedNA= Compound Not Analyzed for by Laboratory.BDL= Below Detection Limits.Result= Result Exceeds Laboratory Detection LimitsResult= Result Exceeds 2L StandardResult= Result Exceeds GCL ValueNC 2L Standard 214 & 216 Hunt StreetGCLs for GroundwaterSampleIDDateCollectedAnalytical Method8260D - Volatile Organic Compounds6000/7000 Series Metals8270E - Semi-Volatile Organic CompoundsLambert Development Hunt Street II, LLCTable 3Durham, Durham County, North CarolinaWR Project Number: 02191245.00Summary of Groundwater Analytical Results (VOCs, SVOCs, & Metals)Page 1 of 1 APPENDIX B Method : Modified TO-15-LL SG + Naph Compound Rpt. Limit (ug/m3) 2.5Freon 12 0.70Freon 114 1.0Chloromethane 0.26Vinyl Chloride 0.221,3-Butadiene 19Bromomethane 1.3Chloroethane 0.56Freon 11 3.8Ethanol 0.77Freon 113 0.401,1-Dichloroethene 4.8Acetone 4.92-Propanol 16Carbon Disulfide 1.63-Chloropropene 1.7Methylene Chloride 0.36Methyl tert-butyl ether 0.40trans-1,2-Dichloroethene 1.8Hexane 0.401,1-Dichloroethane 5.92-Butanone (Methyl Ethyl Ketone) 0.40cis-1,2-Dichloroethene 1.5Tetrahydrofuran 0.49Chloroform 0.541,1,1-Trichloroethane 1.7Cyclohexane 0.63Carbon Tetrachloride 2.32,2,4-Trimethylpentane 0.32Benzene 0.401,2-Dichloroethane 2.0Heptane 0.54Trichloroethene 0.461,2-Dichloropropane 1.81,4-Dioxane 0.67Bromodichloromethane 0.45cis-1,3-Dichloropropene 0.414-Methyl-2-pentanone 3.8Toluene 0.45trans-1,3-Dichloropropene 0.541,1,2-Trichloroethane 0.68Tetrachloroethene 2.02-Hexanone Page 1 Reporting Limits cited do not take into account sample dilution due to canister pressurization. Method : Modified TO-15-LL SG + Naph Compound Rpt. Limit (ug/m3) 0.85Dibromochloromethane 0.771,2-Dibromoethane (EDB) 0.46Chlorobenzene 0.43Ethyl Benzene 0.43m,p-Xylene 0.43o-Xylene 0.42Styrene 1.0Bromoform 0.49Cumene 0.691,1,2,2-Tetrachloroethane 0.49Propylbenzene 0.494-Ethyltoluene 0.491,3,5-Trimethylbenzene 0.491,2,4-Trimethylbenzene 0.601,3-Dichlorobenzene 0.601,4-Dichlorobenzene 0.52alpha-Chlorotoluene 0.601,2-Dichlorobenzene 3.71,2,4-Trichlorobenzene 5.3Hexachlorobutadiene 1.0Naphthalene Surrogate Method Limits 70-1301,2-Dichloroethane-d4 70-130Toluene-d8 70-1304-Bromofluorobenzene Page 2 Reporting Limits cited do not take into account sample dilution due to canister pressurization. APPENDIX C 75-71-8 76-14-2 74-87-3 75-01-4 106-99-0 74-83-9 75-00-3 75-69-4 64-17-5 76-13-1 75-35-4 67-64-1 67-63-0 75-15-0 107-05-1 75-09-2 1634-04-4 156-60-5 110-54-3 75-34-3 78-93-3 156-59-2 109-99-9 67-66-3 71-55-6 110-82-7 56-23-5 540-84-1 71-43-2 107-06-2 142-82-5 79-01-6 78-87-5 123-91-1 75-27-4 10061-01-5 108-10-1 108-88-3 10061-02-6 79-00-5 127-18-4 591-78-6 124-48-1 106-93-4 108-90-7 100-41-4108-38-3/106-42-395-47-6 100-42-5 75-25-2 98-82-8 79-34-5 103-65-1 622-96-8 108-67-8 95-63-6 541-73-1 106-46-7 100-44-7 95-50-1 120-82-1 87-68-3 2037-26-5 17060-07-0 460-00-4Freon 12Freon 114ChloromethaneVinyl Chloride1,3-ButadieneBromomethaneChloroethaneFreon 11EthanolFreon 1131,1-DichloroetheneAcetone2-PropanolCarbon Disulfide3-ChloropropeneMethylene ChlorideMethyl tert-butyl ethertrans-1,2-DichloroetheneHexane1,1-Dichloroethane2-Butanone (Methyl Ethyl Ketone)cis-1,2-DichloroetheneTetrahydrofuranChloroform1,1,1-TrichloroethaneCyclohexaneCarbon Tetrachloride2,2,4-TrimethylpentaneBenzene1,2-DichloroethaneHeptaneTrichloroethene1,2-Dichloropropane1,4-DioxaneBromodichloromethanecis-1,3-Dichloropropene4-Methyl-2-pentanoneToluenetrans-1,3-Dichloropropene1,1,2-TrichloroethaneTetrachloroethene2-HexanoneDibromochloromethane1,2-Dibromoethane (EDB)ChlorobenzeneEthyl Benzenem,p-Xyleneo-XyleneStyreneBromoformCumene1,1,2,2-TetrachloroethanePropylbenzene4-Ethyltoluene1,3,5-Trimethylbenzene1,2,4-Trimethylbenzene1,3-Dichlorobenzene1,4-Dichlorobenzenealpha-Chlorotoluene1,2-Dichlorobenzene1,2,4-TrichlorobenzeneHexachlorobutadieneToluene-d81,2-Dichloroethane-d44-BromofluorobenzeneSV-1SV-2SV-3SV-4SV-5SV-6SV-7SV-8SV-9SV-10SV-11Notes:1.) All results are provided in µg/m3 (micrograms per cubic meter)2.) Compounds analyzed for by laboratory but not listed were not detected above laboratory detection limits. See the laboratory report included in the Appendix for a full list of constituents. ND= Not Detected by LaboratoryResult= Result Exceeds Laboratory Detection LimitsResult= Result Corresponds to the Maixmum Concentration for that Particular Targeted Compound for Use in NCDEQ Risk CalculatorAnalytical MethodTO-15 - Volatile Organic Compounds (VOCs)DateCollectedSampleIDPage 1 of 1Typical Table for TO-15 Analytical ResultsTable 1Summary of Sub-Surface Vapor Results (VOCs - Detections only)The VegaWR Project Number: 02191245.00214 & 216 Hunt StDurham, Durham County, NC