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wells, depth to water measurements were obtained prior to pumping, prior to termination • of pumping and five days after termination of pumping at a rates commencing at 8 9 gpm and subsequently decreased to 4 gpm and 2 gpm Charts developed from these varied pump rates were created for each well and indicate that pumping MW 10 at 2 gpm effected Sanchez wells MW2, MW3, MW6A, MW6B, MW7A, MW7B, MW8A and MW8B, with Iittle or no effect on Sanchez wells MW4, MW5, MW9A, MW9B and Country Club Food and Fuel wells MWI, MW2, MW3 and MW4, see Table 3 and Charts — Appendix D From April 1, 2005 through November 29, 2005 313,921 gallons of gasoline contaminated groundwater were pumped from MW1O removing 7 gallons of gasoline range hydrocarbons This water was batched treated through the carbon/aeration system and stored in the Baker Tank and then discharged to the sanitary sewer once laboratory analysis indicated that sewer discharge parameters were met, see Table 4 and Appendix C, Sewer Discharge Reports The most recent sample event (October 20, 2005) continues to show a reduction in TPHg in the groundwater Comparing TPHg concentrations prior to over-excavation of the UST area (MWIO/R1A and RIB) show concentration reduction from 54,000 ug/L (November 2002 at RIA) to 18,000 ug/L (July 2004 at MW I O) to the most recent 8,000 ug/L (October 2005 at MW10) Similar reductions are evident in wells 6A and SA Well 6A contained 19,000 ug/L TPHg in November 2002, 16,000 ug/L in July 2004 and currently contains 5,200 ug/L (October 2005) Although MW8A was not installed prior to the over-excavation, destroyed well MWI was in close proximity MWI contained 34,000 ug/L in November 2002, MW8A contained 16,000 ug/L in July 2004 and . currently contains 2,700 ug/L (October 2005) Pumping from MW 10 has shown to capture the gasoline range hydrocarbon groundwater plume A Corrective Action Plan (CAP) should be developed that incorporates the groundwater pumping from MW 10 as the primary remediation strategy for this site TIME FRAME February, 2006 1" Quarter 2006 monitoring and sampling To be coordinated with AGE for same time DTW and sampling February 2006 Submittal of Corrective Action Plan (CAP) LIMITATIONS The discussion presented in this report is based on the following I The observations and data collected by field personnel 2 The results of laboratory analyses performed by a state certified analytical laboratory 3 Our understanding of the regulations of San Joaquin County and State of California 12 Sanchez QM 4th 2005