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All soil and well materials will be properly containerized for disposal. All groundwater displaced during drilling activities will be containerized for proper disposal. Ground Zero recommends drilling out fifteen (15) wells including monitoring wells MW-1, MW- 4, MW-5, MW-7, MW-102, MW-106, MW-201 and OW-1 and air sparge wells OS-2 and AS-1 through AS-6. Pressure Grout Wells will be destroyed by pressure grouting based on the San Joaquin County and California State Well Standards. A neat cement grout (containing less than 4% bentonite) will be pumped under pressure through a tremie pipe to the bottom of the well. After the groundwater has been removed and the grout has been filled to the top of the well casing, a pressure cap will be fitted to the casing and the well pressurized to 25 psi. If the grout settles, additional grout will be pumped into the well casing. This assures grout is pumped into the filter pack. Following grouting, at least the top three (3) feet of the well will be drilled out with an auger that is at least one (1) foot larger in diameter than the auger originally used to install the well. In addition, the soil around the cut-off casing will be removed to a depth of an additional six (6) inches below the top of the cut-off casing. Upon filling the rest of the casing, grout sealant will be allowed to spill out of the top of the well casing to form a mushroom cap seal, with at least six (6) inches of grout both below and above the casing. All soil will be properly containerized for disposal. All groundwater displaced to the surface during grout installation will be pumped out of the excavation and containerized for proper disposal. Ground Zero recommends pressure grouting nineteen (19) wells including monitoring wells MW- 2, MW-3, MW-6, MW-8, OS-1, OW-2, MW-2x, MW-101, MW-105, SW-101, SW-102, MW- 107 and MW-202 and vapor extraction wells VEW-1 through VEW-6. The estimated volume of grout required to destroy each well is summarized in Table 6. The grout calculations are included in Attachment D. Variances & Requests Ground Zero recommends allowing variances to the standard destruction methods discussed above to be used in the destruction of the following wells: MW-2x and OS-1 Due to their close proximity to a bare underground fiber optic communication line, Ground Zero recommends pressure grouting and not over-drilling out the upper three (3) feet due to the possibility of damaging to the fiber optic line. Additionally OS-1 has a 1/2-inch stainless steel casing that cannot be drilled out. The limits of the fiber optic line trench are shown in Figure 2 of Attachment B and in a picture included in Attachment E. The utility company has indicated that the line is not contained within a conduit and is not straight, weaving throughout the trench. The line is estimated to be approximately one foot below grade surface. MW-8, MW-101, MW-105 and SW-102 Samples collected during the installation of MW-3 and SW-102 reported minor soil contamination; however all groundwater samples collected from these wells have been reported to be non-detect above laboratory reporting limits. Soil samples collected from MW-8 were reported to be non-detect above laboratory reporting limits, however minor concentrations of TPHg and BTEX compounds were reported in groundwater between 2004 and 2008, but have Page 2 of 4