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07 January 2013 AGE-NC Project No. 98-0500 Page 2 of 4 DRILLING DESTRUCTIONS Based on results from historical investigations (soil and ground water sampling) remediation well (VW-1 to VW-19 - multiple levels) and IAS wells IAS-1 through IAS-14 are wells installed at the site with significant reported petroleum hydrocarbon (total petroleum hydrocarbons,volatile organic compounds: including 1,2-dichloroethene(DCA) impact to either soil or ground water. One ground water extraction well (EW-1) is located near the western edge of the dissolved DCA plume. Therefore, AGE proposes to re-drill the remediation wells installed total depth of the wells (e.g. 76 feet below surface grade [bsg] for IAS well with eight inch augers and 21 to 31 feet bsg for shallow SVE wells or 41 to 56 feet bsg for deep SVE wells with eight inch augers). The EW well will be drilled to approximately 70 feet bsg, with ten-inch augers. The remaining monitoring wells have been installed on-site, into areas of known contamination or had previous detections of contamination. This extensive set of on-site, monitoring well will be required to be re-drilled. Wells are installed to depth of 250 feet and less on-site. Well MW-26 and MW-27 will be re-drilled to 100 feet bsg with ten inch augers to removal all well construction material. The monitoring well construction depths are presented in an attached appendix; therefore, the remaining impacted wells will be re- drilled with eight inch augers. GROUT DESTRUCTIONS AGE proposes to pressure grout the two off-site, non-impacted wells, MW-4 and MW-29 (installed to a depth of 60 feet bsg and 100 feet bsg) and on-site wells without impact are wells MW-10 through MW-14, well MW-21 which are proposed for pressure grout destruction. The wells are listed on the attached tables with a highlight. All wells, pressure grouted or over-drilled, will be destroyed in accordance with the SJCEHD Standard. PROCEDURES An updated 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 drilling location will be clearly marked and an utility clearance obtained through Underground Service Alert. Also to be submitted with this work plan, are the monitoring well destruction permits and associated fees, an encroachment permit and the SJCEHD Master File Record (MFR) information form to expedite the well destruction activities.