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 the well. Chemical analysis results for that sample indicated the presence of sulfolane at a concentration of 5,500 pg/L. 2.3 Investigation-Derived Waste Management Waste soil generated from the advancement of borings was placed in roll-off bins or Department of Transportation-(DOT-)approved 55-gallon drums suitable for transportation for off-site disposal at a permitted waste management facility.The soil in roll-off bins was transported to Potrero Hills Landfill in Suisan, California,for disposal as non-hazardous waste on February 9,2013. The soil in the 55-gallon drums was transported to the US Ecology Landfill in Beatty, Nevada for disposal as non-hazardous waste. Groundwater from development activities and wastewater generated during decontamination procedures were treated in the on-site groundwater treatment system. Copies of the non-hazardous waste manifests are provided in Appendix D. 2.4 Summary and Next Steps Extraction wells EW-10, EW-11, EW-12A, EW-12B(R), EW-13, EW-14A, EW-146, EW-15A, EW-156, and EW-17 were installed to enhance hydraulic containment and to expedite the removal of Site CDCs, including DBCP-, EDB-, and sulfolane-affected groundwater in the water table shallow, intermediate, and deep groundwater zones.The newly installed extraction wells will be connected to the on-site groundwater treatment system to allow for treatment of groundwater extracted from these new wells. 3. Injection Well Conversion Conversion of extraction wells EW-03 and EW-04 into injection wells(INJ-13 and INJ-14, respectively) was proposed in the addendum dated September 13, 2012(ARCADIS 2012b). Redevelopment activities were conducted at EW-03 on August 16,2012 and December 17 and 18, 2012.The redevelopment activities conducted at EW-03 on August 16, 2012 included brushing, surging, bailing, and pumping.Approximately 3,150 gallons of groundwater were pumped from EW-03 to remove fine- grained sediment from the well and obtain an estimate of specific capacity. Pumping indicated a specific capacity of approximately 30 gallons per minute per foot(gpm/ft). This specific capacity indicates injection rates of approximately 100 to 120 gpm are feasible. During the August redevelopment,the field crew also attempted to remove the packer set at 126 feet bgs but was unsuccessful. On December 17, 2012,the packer was pushed to approximately 185 feet bgs after attempts to remove it were unsuccessful.The targeted injection rate for EW-03 is 100 gpm. Specific-capacity measurements indicate feasible injection rates greater than or equal to the targeted injection rate at EW-03 and that conversion to an injection well is feasible. Based on those findings,ARCADIS will continue with conversion of EW-03 to an injection well. lethrop wall installation report final_(042813).dmx 7