WORK PLANS_PART 2 FILE 1 - Laserfiche WebLink

Home Browse Search

Extraction Well Installation Summary Report and Injection ARCADIS Well Installation Work Plan Former Occidental Chemical Corporation Facility Lathrop, California 1. Introduction On behalf of Glenn Springs Holdings, Inc.,ARCADIS U.S., Inc. (ARCADIS)has prepared this Extraction Well Installation Summary Report and Injection Well Installation Work Plan(report)for the former Occidental Chemical Corporation manufacturing facility(Site). The Site is located at 16777 South Howland Road near the southwestern corner of Louise Avenue and South Howland Road in Lathrop, San Joaquin County, California(Figures 1 and 2). The well installation activities summarized in this report were recommended in the Well Installation and Hydraulic Testing Report and Additional Well Installation Work Plan, dated February 28, 2012(work plan;ARCADIS 2012a), and the Addendum to the Well Installation and Hydraulic Testing Report and Additional Well Installation Work Plan(addendum; ARCADIS 2012b), dated September 13, 2012.The work plan and addendum activities were approved by the California Regional Water Quality Control Board—Central Valley Region (RWQCB)in their letter dated November 9, 2012(RWQCB 2012). The objective of the extraction well installation is to expedite the removal of Site contaminants of concern (COCs), including 2,3,4,5-tetrahydrothiophene-1,1-dioxide-(sulfolane-), 1,2-dibromo-3- chloropropane-(DBCP-), and ethylene dibromide-(EDB-)affected groundwater.The current on-site extraction and injection well network has been expanded using a phased approach. The first phase included installation and hydraulic testing of extraction well EW-09,which was completed within the water-table depth interval. Results of that work were presented in the work plan dated February 28, 2012(ARCADIS 2012a). The next phase included installation of 10 extraction wells(EW-10, EW-11, EW-12A, EW-12B(R), EW-13, EW-14A, EW-1413, EW-15A, EW-156, and EW-17)and is summarized herein. Extraction well EW-12B was also installed; however,during development, it was determined that grout had entered the sand pack and screen and was,therefore, abandoned and replaced with extraction well EW-12B(R).Additionally, this report summarizes activities conducted to convert extraction wells EW-03 and EW-04 to injection wells and includes the proposed scope of work for installation of injection well INJ-14. 2. Extraction Well Installation Activities 2.1 Pre-Field Activities The following activities were implemented prior to initiating the investigation.- 0 nvestigation:• A boring permit was obtained from the San Joaquin County Environmental Health Department (SJCEHD)for the soil boring activities.A copy of the boring permit is provided in Appendix A. i h.p—u n�]W.n�p q_fi-1(oa-zvis)a— 1