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1P•� Christopher M. Palmer, PG, CEG, HG, Consulting Hydrogeologist 1345 Kimberly Drive San Jose, CA 95118 ph.408/267-5238;fax 408/267-7396 CMPRGCEGHG@aol.com Wright Environmental Services, Inc. last sampled the wells in August 2009 (See References). No petroleum hydrocarbon constituents were detected in groundwater collected during the final sampling event. The EHD states two options for well destruction procedures: • Option 1. Wells that have laboratory data from the last sampling event that demonstrate presence of any contaminants of concern are to be destroyed by removing all the contents of the original borehole (well casing, screen, filter pack and grout sealant). The cleared borehole is then to be sealed with neat cement by grouting from the bottom to top up to a depth of three feet below grade. All groundwater displaced to the surface during grout installation shall be pumped out of the excavation and containerized for proper disposal. Any wells located offsite require updated access agreements an/or encroachment permits to be submitted along with the EHD Well Destruction Permit Application • Option 2. Wells that have laboratory data from the last sampling event that report non-detectable concentrations of contaminants of concern, with acceptable laboratory detection limits, may be destroyed by pressure grouting with neat cement, applied from the bottom up via tremie pipe, while leaving the casing in place. Following that, a hole at least one foot larger that the originally drilled borehole shall be excavated around the outside of the of the well casing to a depth of 3 feet below grade, and the well casing shall be cut off 6 inches above the bottom of this excavation and removed. The grout will used to seal the well shall then be topped off and allowed to spill over the into the excavation and fill it for a thickness of one foot to form a "mushroom cap" over the top of the cut casing. All groundwater displaced to the surface during grout installation shall be pumped out of the excavation and containerized for proper disposal. Any wells located offsite require updated access agreements an/or encroachment permits to be submitted along with the EHD Well Destruction Permit Application Well destruction Option 1 is proposed for destroying wells MW-1, MW-2, and MW-3 since the wells are within City sidewalks and paved areas. Upon EHD review and approval of the workplan, the City of Tracy will contract the qualified well drilling contract to perform the well destruction work and that will include: • The drilling contractor will prepare and submit the EHD well destruction permits. All work will be performed according to the San Joaquin County Well Standards requirements under the approved permits. Page 2 of 3