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Mr. James L.L. Barton, P.G. December 30, 2015 Page 2 of 4 At least one week prior to beginning the well destruction field work, Ramage Environmental contacted EHD and Underground Service Alert(USA) to schedule regulatory and underground utility clearance inspections (USA Ticket #563863 and 563872). Destruction of Groundwater Monitoring Wells Between November 16, and 18, 2015, under EHD inspection and Ramage Environmental supervision, V&W Drilling, Inc. (V&W), a California licensed drilling contractor(C-57 License #720904) destroyed the eight groundwater monitoring wells associated with the site (MW-1 through MW-8). The locations of the monitoring wells are shown on the attached Site Plan (Figure 2). The construction details for the eight site groundwater monitoring wells are summarized in the following table: WELL BORING BORING WELL WELL SCREEN FILTER BENTONITE CEMENT ID DEPTH DIAMETER DEPTH DIAMETER INTERVAL PACK SEAL SEAL MW-1 65' 8" 65' 2" 45-65' 43-65' 41-43' 0-41' MW-2 65' 8" 65' 2" 45-65' 43-65' 41-43' 0-41' MW-3 65' 8" 65' 2" 45-65' 43-65' 41-43' 0-41' MW-4 60' 8" 60' 2" 40-60' 38-60' 33-38' 0-33' MW-5 60' 8" 60' 2" 40-60' 38-60' 35-38' 0-35' MW-6 60' 8" 60' 2" 40-60' 38-60' 33-38' 0-33' MW-7 60' 8" 60' 2" 40-60' 38-60' 35-38' 0-35' MW-8 60' 8" 60' 1 2" 40-60' 38-60' 35-38' 0-35' As directed by EHD, V&W destroyed six monitoring wells (MW-1 through MW-6) with concentrations of petroleum compounds above laboratory reporting limits in the most recent groundwater sampling event by the over-drill method. Monitoring wells (MW-7 and MW-8) did not contain concentrations of any petroleum compounds above laboratory reporting limits in the most recent groundwater sampling event, and were destroyed by the pressure grout and mushroom cap method. Prior to destroying all of the wells, V&W measured the total depths of the wells to ensure that the well casings were clear and intact. To destroy MW-1 through MW-6 by the over-drill method, V&W removed the street boxes, and drilled-out the wells with 8-inch diameter hollow-stem augers, which were equal in diameter to the well borings. V&W continued drilling until the total depths of the wells were reached and all well screens, well casings, filter packs, and annular seal materials were removed. Following the over- drilling of the wells, V&W filled the boreholes with neat cement grout through a tremie pipe to within three feet of surface grade. V&W completed the upper three feet of the boreholes with compacted soil and surface patches matching the surrounding material.