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Home My WebLink About12033_N Tryon Well Installation WP 2013_11_25 Sent Via Email November 25, 2013 NC DENR Brownfields Section 1314 Mallard Ridge Rd Tega Cay, SC 29708 Attn: Carolyn F. Minnich Re: Well Installation and Groundwater Monitoring Work Plan North Tryon Brownfields Site Brownfields Project #12033-08-06 Charlotte, North Carolina H&H Job No. MVT-018 Dear Carolyn: 1.0 Introduction and Background On behalf of MV Tryon II, LLC (MV Tryon) Hart & Hickman, PC (H&H) is submitting this Well Installation and Groundwater Monitoring Work Plan (Work Plan) for the North Tryon Street Site located at 2109 to 2229 North Tryon Street in Charlotte, Mecklenburg County, North Carolina (Figure 1). Per discussions with the Department of Environment and Natural Resources (DENR) and in accordance with paragraph 13.d. of the Brownfield Agreement (BFA), a downgradient monitoring well is to be installed at 2229 North Tryon Street, the former Latimer Property. Details of the well installation and sampling procedures are described in the following sections. The former Latimer property is an approximate 0.23-acre parcel of land located at the west corner of North Tryon Street and W. 26th Street (Figure 2) and is currently covered with gravel. According to previous assessment activities, a gas station and dry-cleaning facility previously operated on the subject property from the 1940s until the 1970s. Site assessment activities conducted at the property between 2008 and 2013 have indicated the presence of volatile organic Ms. Carolyn Minnich November 25, 2013 Page 2 S:\AAA-Master Projects\Mount Vernon - MVT\MVT-018 Tryon Brownfield Well Install\FINAL Well Installation Work Plan - Tryon St Brownfield.docx compounds (VOCs), predominately tetrachloroethene (PCE) and its degradation products above regulatory screening levels in soil, soil gas, and groundwater. 2.0 Well Installation The most elevated concentrations of VOCs in groundwater, including PCE up to 6,580 µg/L, were historically detected in TW-DPT-1. The potentiometric surface generally slopes to the east. Therefore, the proposed monitoring well will be installed to the east and downgradient of TW- DPT-1 at the location depicted on Figure 2. H&H will obtain a Subsurface Investigation Permit (SIP) from Mecklenburg County prior to the installation of the monitoring well. Prior to installation, H&H will also contact the public utility locators. In addition, H&H will contract with a private utility locator to clear the proposed monitoring well location. The monitoring well will be installed using hollow stem augers by a North Carolina licensed driller and installed such that the screened interval of the well brackets the water table. In 2008, groundwater was encountered at the site at 16 to 17 ft below ground surface (bgs). Therefore, the well will be installed to an estimated depth of 25 ft bgs. The well will be constructed with 2- inch diameter PVC casing and a 15 ft 0.010-inch PVC well screen. Following installation, the well will be developed following standard protocol. 3.0 Groundwater Sampling Methods Per the BFA, a groundwater sample will be collected from the well within two weeks of the well installation. In addition, the BFA requires annual sampling of the monitoring well for five years following the initial event. Ms. Carolyn Minnich November 25, 2013 Page 3 S:\AAA-Master Projects\Mount Vernon - MVT\MVT-018 Tryon Brownfield Well Install\FINAL Well Installation Work Plan - Tryon St Brownfield.docx Groundwater samples from the monitoring well will be collected using a PVC or polyethylene bailer. Prior to collecting the sample, the well will be purged and readings of pH, oxidation reduction potential (ORP), conductivity, and temperature will be recorded until stabilization is reached. Following stabilization, groundwater samples will be collected directly into laboratory supplied containers, immediately placed on ice, and shipped to a North Carolina certified laboratory under standard chain-of-custody protocol. Samples will be analyzed for volatile organic compounds (VOCs) by EPA Method 8260 and semi-volatile organic compounds (SVOCs) by EPA Method 8270. 4.0 Investigation Derived Waste Investigation derived waste (IDW) will be containerized during the monitoring well installation because concentrations of PCE in groundwater detected in 2008 were up to 6,580 µg/L. Soil cuttings and development/purge water will be containerized separately. A sample of the soil cuttings will be collected and analyzed for VOCs using the Toxicity Characteristic Leaching Procedure (TCLP). Groundwater analytical data will be utilized to profile development and purge water. Disposal will be based on the results of the analytical data. Should analytical data indicate that the material is non-hazardous, soil and water will be spread on-site in accordance with DENR IHSB Guidelines. Purge water from future sampling events would then also be spread on-site unless concentrations increase and approach characteristically hazardous thresholds. If analytical data indicate the IDW to be characteristically hazardous, it will be appropriately profiled and disposed off-site at a facility permitted to accept such waste. 5.0 Reporting Following initial well installation and sampling, H&H will submit a Groundwater Monitoring Report detailing the well installation activities and results of the groundwater sampling event. The report will include a description of the monitoring well installation and sampling methods, a summary of the groundwater sampling results and field measurements, the laboratory analytical Ms. Carolyn Minnich November 25, 2013 Page 4 S:\AAA-Master Projects\Mount Vernon - MVT\MVT-018 Tryon Brownfield Well Install\FINAL Well Installation Work Plan - Tryon St Brownfield.docx report along with chain-of-custody, and a site figure. Following each subsequent annual sampling event, H&H will submit a similar Groundwater Monitoring Report. If you have any questions or comments, please do not hesitate to contact us. Sincerely, Hart & Hickman, PC Joselyn Harriger, PG Matt Bramblett, PE Senior Project Geologist Principal Attachments cc: Holly Widders, Mount Vernon Asset Management (1 copy via email) 0 2000 4000 APPROXIMATE SCALE IN FEET N U.S.G.S. QUADRANGLE MAP QUADRANGLE 7.5 MINUTE SERIES (TOPOGRAPHIC) TITLE PROJECT SITE LOCATION MAP NORTH TRYON ASSEMBLAGE LATIMER PROPERTY CHARLOTTE, NORTH CAROLINA DATE: JOB NO: REVISION NO: FIGURE: 11-13-13 0 1 MVT-018 CHARLOTTE EAST, NC 1967 REVISED/INSPECTED 1988 DERITA, NC 1993 SITE