SITE INFORMATION AND CORRESPONDENCE FILE 1

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�6RO Ms. Mary Meays March 8, 1995 (94-47-8620) CONTINGENCIES FOR EMISSION CONTROL A vapor extraction system employing up to three wells (MW-1,RW-1, and MW-5) around the proposed excavation has been operating almost continuously since December 13, 1994. This system has reduced volatile organic vapors in the subsurface. Routine air monitoring with a photoionization detector will be performed during excavation activities to monitor vapor emissions. In the event excessive fugitive emissions are generated, construction operations will be shutdown temporarily, if warranted, until the emissions abate. If conditions persist, engineering controls will be considered. Every effort will be made to take advantage of favorable weather conditions in order to minimize fugitive emissions. SOIL DISPOSAL Fugro will expedite disposal of impacted soil from the former UST basin at the Forward Landfill in Manteca, California. The soil has already been profiled from previous sampling. All stockpiled soil will be placed on and under plastic sheeting while arrangements are made for proper disposal. FLUID EVACUATION FROM EXCAVATION Recent well gauging indicates groundwater is approximately 12 to 13 feet bg. A vacuum truck will be on call to evacuate fluids from the excavation if necessary. Because liquid petroleum hydrocarbons (LPH) have been observed in wells MW-1, RW-1, and MW-5, the infiltration of water and/or LPH into the excavation is anticipated. If LPHs are present, all work in the vicinity of the excavation will cease until the LPHs have been evacuated. If groundwater recharges into the excavation, a sample will be collected, as required in the Tri- Regional Guidelines, and analyzed for TPH, as gasoline, BTEX, and total lead. WELL DECOMMISSIONING Decommissioning of wells MW-1 and RW-1 will be performed prior to excavation. Per Mary Meays of the SJCPHS/EHD, Fugro proposes to pressure grout the wells with neat cement up to approximately 12 feet bg. Prior to grouting, the bottom of the well will be knocked out using the slide hammer on the drill rig. After the grout has been placed, the well casing will be extracted using the rig's winch. The open hole will then be securely covered until ground- breaking occurs. The open hole will be dug out during UST removal. The SJCPHS/EHD will be notified 48 hours ahead of time to schedule a grout inspection. The permit application for well destruction is included as Attachment 2. 94478620.BAD -2-