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APPENDIX C FIELD PROCEDURES C.1 HYDROPUNCH SAMPLING 1. Hydropunch borings HP 1 and HP2 will be advanced using a CPT rig. 2. Groundwater samples will be collected with a hydropunch sampler. 3. After reaching desired groundwater sample collections depths, the protective shield of the hydropunch will be retracted allowing groundwater to enter the intake screen. 4. Groundwater will be allowed to equilibrate for approximately 15 minutes. 5. A groundwater sample will be collected using dedicated 0.25-inch diameter Teflon tubing fitted with a stainless-steel check valve. 6. All items entering the boring will be cleaned prior to use and between sampling period. 7. Three EPA approved, zero head space, 40 mL vials will be collected from each boring. 8. Each vial will be labeled and placed in a Ziploc bag, into an ice chest, and cooled with ice. 9. The samples will be delivered to the laboratory following collection. Sample handling, transport, and delivery to the laboratory were documented using Chain-of-Custody procedures, including the use of Chain-of-Custody forms. C.2 PROCEDURES FOR MONITORING WELL INSTALLATION 1. The groundwater monitoring well will be constructed of 2-inch diameter, threaded, flush- jointed, Schedule 80 PVC pipe with 0.010-inch slotted screen. 2. The well will be constructed inside the 8-inch diameter hollow stem augers. 3. The well screens will extend from approximately 95 to 105 feet bgs in groundwater monitoring well MW-16 and 70 to 80 feet bgs in groundwater monitoring well MW-17. Blank casing will be placed from the top of the screen to just below the ground surface. 4. The annulus around the screened interval will be backfilled with a screen-washed sand. The sandpack will be placed to a depth of approximately 2 to 3 feet above the screen interval of the well. 5. Following initial placement of the sandpack, the well will be surged and bailed with the drill rig to settle the sandpack and remove any fine sediments that might have entered the well screen during well installation. Additional sand will be placed as required. 6. Hydrated time-release coated bentonite pellets will be placed approximately 2 to 3 feet above the sandpack and allowed to hydrate over the time recommended by the manufacturer. 7. Following placement of the bentonite pellets, the remainder of the boring will be backfilled with neat cement to approximately 1-foot bgs. 8. A traffic bearing well box will be placed above the groundwater monitoring well casing and set in concrete. The well box will be raised slightly above the ground surface to minimize surface water infiltration. C.3 WELL DEVELOPMENT PROCEDURES 1. Groundwater monitoring wells MW-16 and MW-17 will be developed by surging and bailing to remove sediment from the filter pack sand and enhance hydraulic yield of the well. An electric submersible pump will be used to further reduce sediment within the well. 2. Temperature, PH, conductivity, and total dissolved solids (TDS) will be measured during well development. 3. Well purging will be continued until sediment yield from the well is reduced and the temperature, pH, conductivity, and TDS readings are stabilized. FREY Environmental,Inc. Project No. 1095-01