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MR Due to the anticipated depth-to-water being approximately 27 feet bgs, three (3) new monitoring wells are proposed to be advanced to a depth of 50 feet bgs. Each well will be constructed using 2-inch diameter polyvinyl chloride (PVC) casing with a 25-foot long section of 0.020-inch factory slotted screen extending from a depth of approximately 25 to 50 feet bgs in each well (or approximately 5 feet above and 20 feet below the groundwater surface). The well annulus will be packed with Lonestar#2/12 or equivalent sized sand from the total depth of the boring to at least 6 inches above the screened interval, followed by 2.0 feet of hydrated bentonite chips and a neat cement sanitary seal to within six(6) inches of the ground surface. The surface of each well will be completed with a traffic-rated well box set in concrete, and a lockable expanding well plug with lock. Proposed well construction details are presented on Figure 3. The monitoring wells will be constructed and developed in accordance with GHD's Standard Operating Procedures (SOPS)for Monitoring Well Installation and Development (Appendix A). The new wells will be developed a minimum of 48 hours after installation of the sanitary seal. 3.3 SOIL AND GROUNDWATER SAMPLING AND ANALYSIS GHD proposes to collect soil samples from monitoring well borings at 5-foot intervals. Soil samples will be retained at changes in lithology, zones of obvious hydrocarbon impact, and from within the vadose zone. A maximum of two(2) soil samples for chemical analyses will be retained from each of the three(3) monitoring well borings. The soil samples will be submitted to Moore Twining Associates, Inc., (a State- certified laboratory) under proper chain-of-custody procedure for the following analysis: • TPH-G by EPA Test Method 8015M/8260B; • Benzene, toluene, ethyl benzene, and total xylenes (BTEX), 5-oxygenates: Methyl tert-butyl ether(MTBE), Tert-amyl methyl ether(TAME), Tert-butyl alcohol (TBA), Di-isopropyl ether (DIPE), and Ethyl tert-butyl ether(ETBE), 1,2-dichloroethane (1,2-DCA) and ethylene dibromide (EDB) by EPA Test Method 8260B; • TPH-D with silica gel cleanup by EPA Test Method 8015M; • Total recoverable hydrocarbons (TRPH) by SM 5520F/silica gel cleanup; and • Total lead by EPA Test Method 6010. Soil and groundwater sampling and handling will be completed in accordance with the GHD's SOP for Soil and Water Sampling from a Boring with VOCs (Appendix A). 3.4 MONITORING WELL DEVELOPMENT The new groundwater monitoring wells will be developed in accordance with GHD's SOP for Monitoring Well Installation and Development(Appendix A). Well development occurs to remove fine-grained sediment from the well casing and filter pack. The well will be alternately surged and bailed, and then pumped, until extracted water becomes mostly clear or a minimum of 10 well volumes have been purged. The total volume of water removed during well development will be recorded on the field forms, along with the field parameters of dissolved oxygen, pH, temperature, and conductivity. Groundwater generated by the development activities will be contained in DOT approved 55-gallon drums, labeled and stored on site until disposal can be arranged. 03009-10017-37110 4 of 6 March 2014