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HomeMy WebLinkAbout25001 - Dynatech_ Additional Brownfields Assessment Work Plan_Dynatech II and III Via Email October 19, 2021 NCDEQ – Division of Waste Management Brownfields Program 1646 Mail Service Center Raleigh, NC 27699-1646 Attn: Ms. Carolyn Minnich Re: Additional Brownfields Assessment Work Plan Dynatech II and Dynatech III Charlotte, North Carolina Brownfields Project Nos. 25001-21-060 and 25067-21-060 H&H Project No. ABS-002 Dear Carolyn: On behalf of 2213/2218 Toomey Avenue Owner, LLC and 704 West Tremont Owner, LLC, please find the enclosed Additional Brownfields Assessment Work Plan prepared for the Dynatech II and Dynatech III Brownfields properties for your review and approval. Should you have any questions or need additional information, please do not hesitate to contact me at (704) 586-0007. Sincerely, Hart & Hickman, PC Haley Martin, PG Ralph McGee, PG Project Geologist Project Manager Enclosure cc: Mr. Mason Ellerbe, Abacus Capital (Via Email) Ms. Mary Katherine Stukes, Moore & Van Allen (Via Email) 1 https://harthick.sharepoint.com/sites/masterfiles-1/shared documents/aaa-master projects/abacus capital (abs)/dynatech ii/additional brownfields assessment/work plan/25001 - dynatech_ additional brownfields assessment work plan.doc Additional Brownfields Assessment Work Plan Dynatech II and Dynatech III Toomey Avenue and W. Tremont Avenue Charlotte, North Carolina H&H Job No. ABS-002 Table of Contents 1.0 Introduction .............................................................................................................................2  1.1 Previous Assessment Activities .............................................................................................3  1.2 Brownfields Assessment Activities .......................................................................................6  2.0 Additional Brownfields Assessment Activities .....................................................................8  2.1 Sub-Slab Soil Gas Sampling Activities .................................................................................8  2.2 Subsurface Landfill Gas and Pressure Measurements .........................................................10  2.3 Surface Water and Sediment Sampling Activities ..............................................................11  2.4 Quality Assurance – Quality Control ..................................................................................12  2.5 Investigation Derived Waste (IDW) Management ..............................................................13  2.6 Reporting .............................................................................................................................14  List of Figures Figure 1 Site Location Map Figure 2 Site and Historical Sample Location Map Figure 3 Proposed Sample Location Map 2 https://harthick.sharepoint.com/sites/masterfiles-1/shared documents/aaa-master projects/abacus capital (abs)/dynatech ii/additional brownfields assessment/work plan/25001 - dynatech_ additional brownfields assessment work plan.doc Additional Brownfields Assessment Work Plan Dynatech II and Dynatech III Toomey Avenue and W. Tremont Avenue Charlotte, North Carolina H&H Job No. ABS-002 1.0 Introduction On behalf of 2213/2218 Toomey Avenue Owner, LLC and 704 West Tremont Owner, LLC (collectively the Prospective Developer or PD), Hart & Hickman, PC (H&H) is providing this Additional Brownfields Assessment Work Plan (Work Plan) for the Dynatech II and Dynatech III Brownfields properties (Brownfields Project Nos. 25001-21-060 and 25067-21-060, respectively) located at the intersection of Toomey Avenue and W. Tremont Avenue in Charlotte, Mecklenburg County, North Carolina (Site). The Site consists of six parcels (Mecklenburg County Parcel identification Nos. 11906426, 11906417, 11906420, 11906429, 11906428, and 11906424) that total approximately 8.1 acres of land located approximately one mile south-southwest of Uptown Charlotte. A Site location map is provided as Figure 1. The Dynatech II Brownfields property is located at 2213 Toomey Avenue and is improved with an approximate 34,425 square foot (sq ft) commercial/industrial building. The Dynatech III Brownfields property (also referred to as the multifamily parcels in this Work Plan) is located at a portion of 2213 Toomey Avenue, 2207 Toomey Avenue, 2301 Toomey Avenue, 2315 Toomey Avenue (also identified as 728 W. Tremont Avenue), 2325 Toomey Avenue, and 704 W. Tremont Avenue. The Dynatech IV Brownfields property is located at 2320 Toomey Avenue and is improved with an approximate 74,300 sq ft warehouse building. The three individual Brownfields properties (Dynatech II, Dynatech III, and Dynatech IV) will be redeveloped as one larger development. The Site and surrounding area are shown in Figure 2. Planned redevelopment includes renovations and upfit for adaptive commercial/retail re-use of the existing building located at 2213 Toomey Avenue (Dynatech II), new construction for high density residential use (Dynatech III), and renovations and upfit for adaptive commercial/retail re-use of the existing building located at 2320/2330 Toomey Avenue (Dynatech IV). This Work 3 https://harthick.sharepoint.com/sites/masterfiles-1/shared documents/aaa-master projects/abacus capital (abs)/dynatech ii/additional brownfields assessment/work plan/25001 - dynatech_ additional brownfields assessment work plan.doc Plan has been prepared to complete additional assessment activities to address data gaps specific to the Dynatech II and Dynatech III portions of the Site and does not include additional assessment for the Dynatech IV Brownfields property. 1.1 Previous Assessment Activities To obtain additional information, H&H reviewed several reports prepared by others to document previous environmental assessment completed at the Site. A brief summary of information provided in the environmental reports is provided below. Multifamily Parcels In December 2020, Partner Engineering (Partner) completed a Phase I Environmental Site Assessment (ESA) at the multifamily parcels. According to information provided in the Phase I ESA, the multifamily parcels consisted primarily of single-family residences from the early 1930 through 2014. A commercial building (2315 Toomey/728 West Tremont) was constructed on the multifamily parcels in the early 1990s. Results of the Phase I ESA identified the following recognized environmental conditions (RECs) in connection with the Site:  During the Site visit, aboveground storage tanks (ASTs) and 55-gallon steel drums were identified in an area of heavy vegetation near the 2207 Toomey Avenue parcel. Partner was not able to observed the ground surface beneath the stored materials and considered the potential for an undocumented release associated with the ASTs and 55-gallon drums to represent an environmental concern.  Based on available environmental documents, the Powers Site Brownfields property has documented methane gas in the subsurface. The potential for impact to the Site from documented impacts on the adjacent Powers Site Brownfields property was identified as a REC.  Based on available environmental documents, the Adams Brownfields property located on the southeastern adjacent property, has documented methane gas and elevated 4 https://harthick.sharepoint.com/sites/masterfiles-1/shared documents/aaa-master projects/abacus capital (abs)/dynatech ii/additional brownfields assessment/work plan/25001 - dynatech_ additional brownfields assessment work plan.doc concentrations of volatile organic compounds in the subsurface. The potential for impact to the Site from documented impacts on the adjacent Adams Brownfields property was identified as a REC. In addition, Partner identified the discharge of hazardous plating waste to an on-Site septic system located in the southeastern portion of the multifamily parcel to represent a controlled REC (discussed further below). To address environmental concerns identified in the December 2020 Phase I ESA, Partner conducted a Phase II Subsurface Investigation in January 2021. Phase II assessment activities included collection of soil, groundwater, and exterior soil gas samples for laboratory analysis and test pits for geotechnical exploration. In addition, landfill gas and pressure measurements were collected from exterior soil gas monitoring points to evaluate the potential for methane gas in the subsurface. Results of the Phase II assessment activities identified the following:  Semi-volatile organic compounds (SVOCs) were identified at concentrations exceeding the DEQ Inactive Hazardous Sites Branch (IHSB) Residential Preliminary Soil Remediation Goals (PSRGs) in soil samples collected near the septic system in the southwestern portion of the Site.  Groundwater analytical results identified total chromium at concentrations above the North Carolina 2L Groundwater Standard (2L Standard) in a sample collected near the on-Site septic system (B-2GW). Total chromium and lead were also detected in a groundwater sample collected in the northwestern portion of the multifamily parcels (B-4GW) at concentrations above the 2L Standards. According to information provided in the report, the detected metals concentrations are likely due to elevated turbidity in the samples submitted for laboratory analysis.  Results of soil gas sampling identified vinyl chloride and benzene at concentrations above the DEQ Division of Waste Management (DWM) Residential and/or Non- Residential Vapor Intrusion Sub-Slab and Exterior Soil Gas Screening Levels (SGSLs) 5 https://harthick.sharepoint.com/sites/masterfiles-1/shared documents/aaa-master projects/abacus capital (abs)/dynatech ii/additional brownfields assessment/work plan/25001 - dynatech_ additional brownfields assessment work plan.doc in the northern portion of the Site. Low levels of 1,3-butadiene were also detected at concentrations above the DEQ DWM Vapor Intrusion Residential and/or Non- Residential SGSLs in several soil gas samples collected at the Site. Ethylbenzene was also detected at a concentration above the DWM Vapor Intrusion Residential SGSL in the northern part of the multifamily parcels. According to information provided in the Phase II report, risk calculator results indicate that cumulative carcinogenic and cumulative noncarcinogenic risks do not exceed unacceptable levels under a residential use scenario.  Results of landfill gas readings identified the presence of methane at a concentration of 0.672 percent by volume air in one soil gas monitoring point location. Methane was not detected at concentrations above the Lower Explosive Limit (LEL) of 5 percent by volume air in subsurface soil gas measurements.  Test pit exploration found geotechnically unsuitable soils due to debris (wood, masonry, etc.) to depths between approximately 2 and 8 ft below ground surface (bgs) in the northern portion of the multifamily parcels and to a depth of 16 feet bgs in the south-central portion of the multifamily parcels. 2213 Toomey Avenue Parcel According to available environmental documents prepared for the 2213 Toomey Avenue parcel, the Site was developed with the current commercial building by the late 1960s. Site occupants have included a household goods hauling business from the late 1960s to the early 1970s, a retailer of textile machinery from the early 1970s until the mid-1980s, Dynatech Industries, Inc. from the mid-1980s until the early 1990s, and a custom tank manufacturer from the mid-1990s to the early 2020s. Dynatech operations included chrome plating of compressor parts and resulted in generation of hazardous waste. Reportedly, plating waste was discharged to a septic system located on the 2315 Toomey Avenue parcel included as part of the multifamily parcels. Various assessment activities were completed at the 2213 Toomey Avenue property in the 1990s. Results of the assessment activities identified various metals and methyl ethyl ketone (MEK) in 6 https://harthick.sharepoint.com/sites/masterfiles-1/shared documents/aaa-master projects/abacus capital (abs)/dynatech ii/additional brownfields assessment/work plan/25001 - dynatech_ additional brownfields assessment work plan.doc Site media. In the 1990s, soil, groundwater, and wastewater remedial activities were completed under the purview of the United States Environmental Protection Agency (EPA). The Site was entered into the Brownfields program and results of additional assessment activities indicated the Site was eligible for No Further Remedial Action Planned (NFRAP) status under the federal Superfund Program. A Notice of Brownfields Property was recorded on the 2213 Toomey Avenue parcel deed on October 23, 2003. Subsequent compliance certifications indicate that the Site is in compliance with the land use restrictions outlined in the recorded Brownfields Agreement. 1.2 Brownfields Assessment Activities In May 2021, Partner performed a Methane Assessment at the Dynatec II and III Brownfields properties. Assessment activities included installation and sample collection from nineteen landfill gas monitoring points (MSG-4 through MSG-22). Results of the assessment activities identified methane at concentrations up to 36.8 percent by volume air at sample location MSG-16 and up to 20.8 percent by volume air at sample location MSG-18 installed in the northern portion of the Site. Approximate locations of landfill gas monitoring points installed by Partner are depicted in Figure 2. In June 2021, Partner performed Brownfields assessment activities on the Site. Assessment activities included advancement of six soil borings and 32 characterization soil borings for a total of six soil samples and sixteen soil characterization samples selected for laboratory analysis. Assessment activities also included groundwater sample collection from four on-Site monitoring wells. Additionally, soil gas samples were collected on the northeastern portion of the Site from four soil gas sample points previously installed by Partner during the May 2021 Methane Assessment. Historical groundwater and soil gas sample locations are depicted in Figure 2. Laboratory analytical results for the soil samples collected at the Site identified various polycyclic aromatic hydrocarbons (PAHs), organic compounds, and metals at concentrations above the DEQ IHSB Preliminary Soil Remediation Goals (PSRGs) on the multifamily parcels. 7 https://harthick.sharepoint.com/sites/masterfiles-1/shared documents/aaa-master projects/abacus capital (abs)/dynatech ii/additional brownfields assessment/work plan/25001 - dynatech_ additional brownfields assessment work plan.doc Laboratory analytical results for groundwater samples collected downgradient of the 2213 Toomey Avenue Site building indicated that no organic compounds were detected at concentrations above the 2L Standards. Chromium (58.0 µg/L) was detected in one groundwater sample (MW-4) at concentrations above the 2L Standard of 10 µg/L. Partner attributed the elevated metal concentration to high turbidity in the groundwater sample. No other compounds were detected at concentrations above the 2L Standards in the June 2021 groundwater samples collected at the Site. Results of the soil gas sampling activities identified low levels of select petroleum-related compounds at concentrations above the Residential SGSLs. No compounds were detected at concentrations above the Non-Residential SGSLs. According to information provided in available environmental documents, results of risk calculations indicate that compound concentrations detected in the soil gas samples do not exceed acceptable cumulative carcinogenic or noncarcinogenic thresholds under a residential use scenario. The Brownfields Assessment Report prepared by Partner was provided to DEQ on August 13, 2021. As of the issuance of this Work Plan, DEQ has not provided formal approval of the assessment report. The purpose of the additional Brownfields assessment activities described herein are proposed to address DEQ Brownfields Program requests provided in an email dated September 23, 2021 for collection of sub-slab soil gas samples within the 2213 Toomey Avenue Site buildings to evaluate the potential for structural vapor intrusion. In addition, upon review of available information, an intermittent stream was identified in the eastern portions of the Site that has not yet been evaluated. Therefore, additional assessment activities include collection of sediment and surface water (if present) samples from the intermittent stream to evaluate potential impacts to assist in management of Site media during redevelopment and potential risks to Site workers and future Site occupants. A summary of the proposed Brownfields assessment activities is provided below. 8 https://harthick.sharepoint.com/sites/masterfiles-1/shared documents/aaa-master projects/abacus capital (abs)/dynatech ii/additional brownfields assessment/work plan/25001 - dynatech_ additional brownfields assessment work plan.doc 2.0 Additional Brownfields Assessment Activities The proposed assessment activities will be performed in general accordance with the DEQ Inactive Hazardous Sites Branch (IHSB) Guidelines for Assessment and Cleanup of Contaminated Sites (Guidelines) dated July 2021, the DEQ Division of Waste Management (DWM) Vapor Intrusion Guidance (VI Guidance) dated March 2018, and most recent versions of the U.S. Environmental Protection Agency (EPA) Region IV Science and Ecosystem Support Division (SESD) Field Branches Quality System and Technical Procedures guidance. Prior to conducting the proposed assessment field activities, H&H will contact North Carolina 811, the public utility locator, to mark subsurface utilities located on the Site. H&H will also contract with a private utility locator to screen proposed sample locations for subgrade utilities that may not be marked by the public locator. 2.1 Sub-Slab Soil Gas Sampling Activities To evaluate the potential for structural vapor intrusion, H&H proposes to collect six (6) sub-slab soil gas samples (SSV-1 through SSV-6) within the existing 2213 Toomey Avenue Site building. The sub-slab soil gas sample locations may be adjusted to 1) minimize damage to floors or floor coverings, and 2) to analyze sub-slab conditions in areas separated by building footers if indications of building footers are observed during field sample location selection. The approximate locations of the proposed sub-slab soil gas sampling points are shown on Figure 3. The sampling points will be installed using a rotary hammer drill and 1½-inch diameter drill bit to advance a pilot hole into the concrete slab to a depth of approximately 1¾ inches below the slab surface. A drill guide will then be placed within the pilot hole, and a 5/8-inch diameter drill bit will be utilized to advance a boring through the concrete slab. Following borehole advancement, loose concrete cuttings will be removed from each boring, and a Cox-Colvin Vapor PinTM (vapor pin) assembly (brass sampling point and silicone sleeve) will be seated in the borehole using an installation/extraction tool and dead blow hammer to form an air tight seal. 9 https://harthick.sharepoint.com/sites/masterfiles-1/shared documents/aaa-master projects/abacus capital (abs)/dynatech ii/additional brownfields assessment/work plan/25001 - dynatech_ additional brownfields assessment work plan.doc The sub-slab soil gas samples will be collected utilizing a laboratory supplied batch certified stainless steel Summa® canister (1-liter or 3-liter canisters depending on laboratory availability) connected to an air-flow regulator calibrated by the laboratory to collect the soil gas sample at a rate of approximately 100 milliliters per minute. Prior to sample collection, a “shut-in” test will be conducted on the sampling train and helium leak checks will be conducted at each sampling point. The purpose of the shut-in test and helium leak check is to ensure short circuiting with ambient air does not occur during sampling. A description of the shut-in test and helium leak testing procedures is provided below. The shut-in test will be conducted by connecting the flow regulator with the vacuum gauge to the Summa® canister and sealing the flow regulator with the laboratory provided brass cap. Once the sampling train is “closed”, the sample valve on the Summa® canister will be opened and the reading on the vacuum gauge will be recorded. The Summa® canister sample valve will then be closed and the vacuum gauge will be observed to ensure no vacuum loss occurs. If the vacuum reading remains the same, the shut-in test will be considered successful. If vacuum loss occurs, the flow regulator and/or brass cap will be reseated and the shut-in test will be repeated until the vacuum reading remains stable. Following the shut-in test, the Summa® canister will be connected to the sample point via Teflon® sample tubing using a brass nut and ferrule assembly to create an air tight seal and the leak check will be performed. The leak check will be performed by constructing a shroud over the sample train at each sampling point and flooding the air with helium gas. Helium concentrations inside the shroud will be measured using a calibrated helium gas detector and maintained at concentrations of approximately 15% to 30% for the duration of the leak check. Once helium concentrations stabilize within the shroud, the sample tubing will be purged outside of the shroud using a syringe and a three-way valve to collect purged soil gas into a Tedlar® bag. The purged soil gas will then be analyzed using the helium gas detector to ensure that helium concentrations in the sampling train are less than 10% of the helium concentrations measure within the shroud. 10 https://harthick.sharepoint.com/sites/masterfiles-1/shared documents/aaa-master projects/abacus capital (abs)/dynatech ii/additional brownfields assessment/work plan/25001 - dynatech_ additional brownfields assessment work plan.doc Following a successful leak check, the intake valve on the Summa® canister will be fully opened to begin collection of the sub-slab soil gas sample. Vacuum readings on the Summa® canister will be recorded prior to and following the sampling period to ensure adequate sample volume was collected. A vacuum of approximately 5 inches of mercury or more will be maintained within the canisters at the conclusion of the sampling event in accordance with DEQ DWM guidance. Following sample collection, the Summa® canisters will be placed in laboratory supplied shipping containers, properly labeled, and shipped under standard chain-of-custody protocols to a qualified laboratory for analysis of volatile organic compounds (VOCs) by EPA Method TO-15. The laboratory will be requested to use reporting limits that are below DEQ DWM Residential Vapor Intrusion SGSLs. After sample collection, the sample locations will be estimated by measuring from known benchmarks within the building (e.g., doors, windows, exterior walls, etc.). 2.2 Subsurface Landfill Gas and Pressure Measurements In addition to the soil gas sampling activities described above, methane measurements will be collected at each exterior temporary soil gas sampling point. Although, there is no indication a significant and widespread subsurface source for methane at the Site based on prior assessment activities performed near the 2213 Toomey Avenue Site building, H&H proposes to collect an initial round of landfill gas measurements to minimize the potential for data gaps prior to redevelopment of the Site in accordance with DEQ’s request for additional assessment provided on September 23, 2021. Landfill gas measurements will be collected in general accordance with the Los Angeles Department of Building Safety (LADBS) Site Testing Standards for Methane dated January 2014, and the DEQ Brownfields Program Methane Assessment Protocols dated September 2020. The sample tubing for each sub-slab soil gas sampling point will be capped using an air tight petcock valve immediately following installation to allow subsurface conditions to equilibrate 11 https://harthick.sharepoint.com/sites/masterfiles-1/shared documents/aaa-master projects/abacus capital (abs)/dynatech ii/additional brownfields assessment/work plan/25001 - dynatech_ additional brownfields assessment work plan.doc for 2-hours. After allowing for subsurface equilibration, H&H will collect both static and differential pressure readings from each monitoring point. The pressure readings will be collected using a Landtec Gem 5000® and will be collected prior to performing helium leak checks (described in Section 2.1 above). Following collection of the pressure readings, leaks checks described in Section 2.1 will be completed at each sampling point. Following subsurface equilibration and successful leak checks, a Landtec Gem 5000® or equivalent device will be connected to the sample tubing and field measurements of static pressure, oxygen, carbon dioxide, carbon monoxide, hydrogen sulfide, and methane (percent by volume and percent lower explosive limit) will be collected and recorded by sampling personnel. After completion of the first round of measurements, soil gas samples will be collected for laboratory analysis using methods described in Section 2.1 above. Following collection of the soil gas samples, H&H will cap the points with an air tight valve for a minimum of 24-hours prior to collection of a second round of subsurface landfill gas measurements. Following a minimum of 24-hours, H&H will collect one additional oxygen, carbon dioxide, carbon monoxide, hydrogen sulfide, and methane, and pressure measurement from each sample location. To the extent possible, H&H will collect the second round of measurements at a varying time of the day from the time at which the first sample was collected (i.e., day one measurements will be collected in the morning and day two measurements will be collected in the afternoon). A total of two pressure and gas measurements will be collected from each sample location. 2.3 Surface Water and Sediment Sampling Activities According to information provided by the PD, a potential jurisdictional intermittent stream is located in the eastern portion of the Site. H&H proposes to confirm the presence of the tributary and determine if the tributary is a perennial stream during base-flow conditions. If the tributary is present and has flowing water during base-flow conditions, H&H proposes to collect a co- located surface water and sediment sample for laboratory analysis. The approximate extent of 12 https://harthick.sharepoint.com/sites/masterfiles-1/shared documents/aaa-master projects/abacus capital (abs)/dynatech ii/additional brownfields assessment/work plan/25001 - dynatech_ additional brownfields assessment work plan.doc the proposed construction buffer for the stream is shown in Figure 3. Surface water samples will be collected directly into dedicated laboratory supplied sample containers. Sediment samples will be collected using a decontaminated stainless steel trowel and placed directly into dedicated laboratory supplied sample. The samples will be labeled with the sample identification, date, time, and requested analysis and place in a laboratory supplied cooler with ice. The samples will be delivered to a North Carolina certified laboratory under standard chain of custody protocols for analysis of VOCs by EPA Method 8260, semi-VOCs (SVOCs) by EPA Method 8270, and Resource Conservation and Recovery Act (RCRA) metals by EPA Method 6020/7470/7471. The sediment sample will also be submitted to laboratory analysis of hexavalent chromium by EPA Method 7199. The surface water sample will be analyzed for total hardness to allow calculation of hardness dependent 2B Surface Water Standards. 2.4 Quality Assurance – Quality Control Non-dedicated equipment and tools will be decontaminated prior to use at each boring or sampling location or following exposure to soil or groundwater. The following samples will be collected for quality assurance/quality control (QA/QC) purposes:  One duplicate surface water and sediment sample will be collected and analyzed for the same parameters as the parent samples.  One trip blank will accompany the surface water and sediment samples during the field activities as well as during sample shipment and will be analyzed for VOCs by EPA Method 8260.  One duplicate sub-slab soil gas sample will be collected using a laboratory supplied “t- fitting” which allows for two soil gas samples to be collected from one soil gas monitoring point simultaneously. The duplicate soil gas sample will be submitted for analysis of VOCs by EPA Method TO-15. H&H will also collect a confirmation landfill gas and pressure measurement at one sample location. The confirmation gas and pressure measurements will be collected approximately 10 13 https://harthick.sharepoint.com/sites/masterfiles-1/shared documents/aaa-master projects/abacus capital (abs)/dynatech ii/additional brownfields assessment/work plan/25001 - dynatech_ additional brownfields assessment work plan.doc minutes after collection of the parent measurements. Without an extensive sub-surface investigation to monitor sub-surface pressure changes over time, H&H cannot definitively calculate or model decreases in soil gas concentrations and pressure over a 10-minute time interval following collection of the parent measurement. The measurement collection process does not include removal of significant volumes of air. Therefore, the confirmation sample results are expected to be adequate for validation of the parent sample results. Laboratory QA/QC procedures will be employed to ensure appropriate sample handling and analysis and to aid in the review and validation of the analytical data. QA/QC procedures will be conducted in accordance with the method protocols and will include regular equipment maintenance, equipment calibrations, and adherence to specific sample custody and data management procedures. Samples will be analyzed in conjunction with appropriate blanks, laboratory duplicates, continuing calibration standards, surrogate standards, and matrix spiking standards in accordance with approved methodologies to monitor both instrument and analyst performance. Laboratory reporting limits for each analyte will be at or below appropriate screening criteria, where possible. Additionally, H&H will request that the laboratory include estimated concentrations for compounds that are detected at levels above the laboratory method detection limit, but below the laboratory reporting limit (J flags). The laboratory analytical data report and QA package for each group of samples submitted to and analyzed by the subcontracted laboratory will be provided in an appendix to the final report. Laboratory QA data consistent with Level II documentation will be provided for this project. A copy of the completed chain of custody record and shipping receipt will be appended to the corresponding laboratory analytical report included with the final report. 2.5 Investigation Derived Waste (IDW) Management Investigation derived waste (IDW) generated during the proposed assessment activities is expected to be minimal and will be placed back in the holes. However, if significant impacts are suspected (i.e., free-product) the soil cuttings will be containerized in labeled 55-gallon drums and staged on-Site pending analytical results of a composite IDW sample. Based on laboratory 14 https://harthick.sharepoint.com/sites/masterfiles-1/shared documents/aaa-master projects/abacus capital (abs)/dynatech ii/additional brownfields assessment/work plan/25001 - dynatech_ additional brownfields assessment work plan.doc analytical results of IDW samples, the drums will be transported off-Site to a suitable facility. 2.6 Reporting Following completion of the assessment activities and receipt of the analytical data, H&H will document our findings in an Additional Brownfields Assessment Report. The report will include a description of Site activities, rationale for potential deviations from the work plan (if warranted), a figure depicting sample locations, tabular summaries of the data, laboratory analytical data, a discussion of the data in comparison to regulatory screening levels, cumulative risk calculations for sub-slab soil gas analysis (if warranted based upon the data), and conclusions and recommendations concerning our activities. USGS The National Map: National Boundaries Dataset, 3DEP ElevationProgram, Geographic Names Information System, National HydrographyDataset, National Land Cover Database, National Structures Dataset,and National Transportation Dataset; USGS Global Ecosystems; U.S.Census Bureau TIGER/Line data; USFS Road Data; Natural Earth Data;U.S. Department of State Humanitarian Information Unit; and NOAANational Centers for Environmental Information, U.S. Coastal ReliefModel. Data refreshed May, 2020. SITE LOCATION MAP DYNATECH II AND IIITOOMEY AVENUE AND WEST TREMONT AVENUECHARLOTTE, NORTH CAROLINA DATE: 7-28-21 JOB NO: ABS-002 REVISION NO: 0 FIGURE. 1 2923 South Tryon Street - Suite 100Charlotte, North Carolina 28203704-586-0007 (p) 704-586-0373 (f)License # C-1269 / # C-245 Geology TITLE PROJECT 0 2,000 4,000 SCALE IN FEET Path: M:\AAA_DRAFTING\ABS-002\Figure 1.mxdN U.S.G.S. QUADRANGLE MAP CHARLOTTE EAST, NORTH CAROLINA 2013 QUADRANGLE7.5 MINUTE SERIES (TOPOGRAPHIC) SITE REVISION NO. 0 JOB NO. ABS-002 DATE: 9-27-21 FIGURE NO. 2 DYNATECH II AND III TOOMEY AVENUE AND WEST TREMONT AVENUE CHARLOTTE, NORTH CAROLINA SITE AND HISTORICAL SAMPLE LOCATION MAP LEGEND BROWNFIELDS PROPERTY BOUNDARY PARCEL BOUNDARY CO-LOCATED SOIL AND GROUNDWATER SAMPLE LOCATION SOIL GAS SAMPLE LOCATION 2923 South Tryon Street-Suite 100 Charlotte, North Carolina 28203 704-586-0007(p) 704-586-0373(f) License # C-1269 / #C-245 GeologyTOOMEY AVE N UE W TREMONT AVENU E WOODCREST AVENUE B-8/MW-3 MW-4/4R B-2/B-2GW B-1/B-1GW B-4B-4GW B-3/B-3GW NOTES: 1.PARCEL DATA AND AERIAL IMAGERY OBTAINED FROM MECKLENBURG COUNTY GIS, 2021. 2.GROUNDWATER SAMPLES B-1GW THROUGH B-4GW, AND MSVG-1 THROUGH MSVG-7 WERE COLLECTED ON THE EASTERN SITE PARCELS BY PARTNER IN JANUARY 2021. 3.MONITORING WELLS MW-1 THROUGH MW-3 WERE INSTALLED BY PARTNER IN JUNE 2021. WELLS MW-4 AND MW-4R WERE INSTALLED BY OTHERS IN SEPTEMBER 2000. 4.SOIL GAS SAMPLES MSG-4 THROUGH MSG-22 WERE COLLECTED BY PARTNER IN MAY AND JUNE 2021. 5.BPN = BROWNFIELDS PROJECT NUMBER MSVG-5 MSVG-7 MSVG-6 MSVG-1 MSVG-2 MSVG-3 MSVG-4 MSG-15 MSG-19 MSG-16 MSG-17 704 W. TREMONT AVENUE2325 TOOMEY AVENUE 728 W. TREMONT AVENUE 2213 TOOMEY AVENUEDYNATECH IV BROWNFIELDS PROPERTY 2320 TOOMEY AVENUE (BPN 25068-21-060) POWERS SITE BROWNFIELDS PROPERTY (BPN 20045-16-060) MSG-1 MSG-2 MSG-3 MSG-22 MSG-21 MSG-20 MSG-18 MSG-14 MSG-12 MSG-13 MSG-10 MSG-11 MSG-9 MSG-8 MSG-7MSG-4 MSG-5 MSG-6 M:\AAA_DRAFTING\ABS-002\Site Map.dwg, 10/15/2021 8:28:42 AM, shaynes REVISION NO. 0 JOB NO. ABS-002 DATE: 10-1-21 FIGURE NO. 3 DYNATECH II AND III TOOMEY AVENUE AND WEST TREMONT AVENUE CHARLOTTE, NORTH CAROLINA PROPOSED SAMPLE LOCATION MAP LEGEND BROWNFIELDS PROPERTY BOUNDARY PARCEL BOUNDARY APPROXIMATE INTERMITTENT STREAM BUFFER PROPOSED SUB-SLAB SOIL GAS SAMPLE LOCATION 2923 South Tryon Street-Suite 100 Charlotte, North Carolina 28203 704-586-0007(p) 704-586-0373(f) License # C-1269 / #C-245 GeologyTOOMEY AVE N UE W TREMONT AVENU E WOODCREST AVENUE NOTES: 1.PARCEL DATA AND AERIAL IMAGERY OBTAINED FROM MECKLENBURG COUNTY GIS, 2021. 2.BPN = BROWNFIELDS PROJECT NUMBER 3.APPROXIMATE STREAM BUFFER OBTAINED FROM THE SITE PLAN PREPARED BY THE JOHN R. McADAMS COMPANY, INC., DATED JULY 2021. 704 W. TREMONT AVENUE2325 TOOMEY AVENUE 728 W. TREMONT AVENUE 2213 TOOMEY AVENUE POWERS SITE BROWNFIELDS PROPERTY (BPN 20045-16-060) DYNATECH IV BROWNFIELDS PROPERTY 2320 TOOMEY AVENUE (BPN 25068-21-060) SSV-6 SSV-4 SSV-5 SSV-3 SSV-2 SSV-1 M:\AAA_DRAFTING\ABS-002\Site Map.dwg, 10/18/2021 9:30:34 AM, shaynes