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20 October 2014 AGE Project No. 09-1729 Page 2 of 3 The following is a summary of all the wells total depths: • Monitoring wells MW-1 MW-2, MW-3, MW-5, MW-6, MW-7, MW-8 and MW-10: 30 feet below surface grade (bsg); • Monitoring well MW-9: 29 feet bsg; • Monitoring wells MW-4 and MW-11: 80 feet bsg; • Soil vapor extraction wells VW-1, VW-2 and VW-3: 20 feet bsg • Ozone wells OZ-1 and OZ-2: 27 feet bsg. Utilizing historical soil and groundwater data (Tables 2 through 4) and based on SJCEHD well destruction requirements, wells MW-1 through MW-8, MW-11, VW-1 through VW-3 and OZ-1 and OZ-2 will be overdrilled, while wells MW-9 and MW-10 will be pressure grouted. All site wells will be destroyed in accordance with SJCEHD well standards and California Well Standards Bulletins 74-81 and 74-90. PROCEDURES As required, a health and safety plan will be prepared in accordance with Occupational Safety and Health Guidance Manual for Hazardous Waste Site Activities (National Institute for Occupational Safety and Health Administration, U.S. Coast Guard and U.S. Environmental Protection Agency, 1985). Prior to drilling activities, each proposed location will be clearly marked and an utility clearance will be obtained through Underground Service Alert. The required well destruction permits will be obtained from the SJCEHD prior to destruction activities. Before commencement of drilling, all wells will be checked for total depth and integrity using a Solinst water level meter. Any obstructions found in the well will be removed. Wells proposed for over drilling (MW-1 through MW-8, MW-11, VW-1 through VW-3 and OZ-1 and OZ-1), will be drilled-out to one foot deeper than their installed total depths utilizing either 8-inch (MW-1 through MW-8 and OZ-1 and OZ-2) or 10-inch (VW-1 through VW-3). All original well construction materials will be removed (including well casing, screen, filter pack, and annular seal) to ensure that no residual contamination is sealed within the destroyed borehole. Remaining boreholes will be backfilled to surface grade with neat portland cement and covered with concrete, asphalt, or native soil, depending on the surrounding surface material. For wells proposed for pressure grouting (MW-9 and MW-10) the well box and cap will be removed to expose the well casing. Each well will be initially filled over its entire Advanced GeoEnvironmental,Inc.