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Christopher M. Palmer, PG, CEG, HG, Consulting Hydrogeologist 1346 Kimberly Drive San Jose, CA 95118 ph.4081267-5238;fax 4081267-7396 GMPRGCEGHG@aol.com Monitoring Well Destruction Approach There are four monitoring wells on the Boyd Service Center site at the locations shown on Figure 2. The exploratory boring logs and monitoring well construction details for each well are also attached. Wright Environmental Services, Inc. last sampled the wells at the subject property in 2011 (see References). Groundwater samples collected In February 2011 indicated the presence of Total Petroleum Hydrocarbons as Diesel (TPHD) present in Wells MW-1 (2,600 ugll), MW-2 (52 ug/1) and MW-3 (260 ugli). TPHD was not detected in MW-4. Ethylbenzene was reported in MW-1 at a concentration of 0.54 ug/i. Benzene, MTBE, Methanol and Ethanol were not detected in any well. 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 sam ling event that report non-detectable concentrations of contaminarits f ncern, with acceptable laboratory detection limits, may be d pressure grouting with neat cement, applied from the bo r mie pipe, while leaving the casing in place. Following th a ; e st one foot larger that the originally drilled borehol s a x around the outside of the of the well casing to a de e w grade, and the well casing shall be cut off 6 inch a v of this excavation and removed. The grout will use o a eWa all then be topped off and allowed to spill over theo do nd fill it for a thickness of one foot to form a "mush om r top of the cut casing. All groundwater displacq to rfac rt�ring grout installation shall be pumped out of the exc nation a nt inerized for proper disposal. Any wells located oI q dated access agreements an/or encroachmen r ubmitted along with the EHD Well Destruction P i ti Page 2 of 4