ARCHIVED REPORTS XR0006463 - Laserfiche WebLink

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off-site MW6 and MW9 are located in the parking lot north and east of the site (Lincoln Village Properties) MW7 is located in the sidewalk south across Douglas Boulevard (San Joaquin County easement) MW5 and MWS are located east across Pacific Avenue (City of Stockton landscape road easement areas) MWl 1 is located in the Festival Cinema parking lot (Mann Theaters Corp property) and MW12 is located in the planter southwest of the Kragen Auto Parts store (property owned by Dr Sidney Kerston) WELL DESTRUCTION San Joaquin County Public Health Services, Environmental Health Division (SJCPHS,EHD)- Well Standards 13 17 1 through 13 17 15 lists the requirements for destroying monitoring wells, see Appendix A Based on the review of the above mentioned standards the wells will be destroyed in the following manner Pressure Grout Monitor Wells MW4, MWS, MW6, MW7, MW9, N\ 11 and MW12 Groundwater monitoring wells MW4, MW5, MW6, MW7, MW9, MWl1 and MW12 will be pressure grouted The following wells contained no evidence of soil contamination and were below laboratory lower detection limits for gasoline (TPHg), benzene, toluene, ethyl benzene, xylenes (BTEX) and fuel oxygenates in groundwater (MtBE was the only oxygenate found in soil and groundwater samples at this site) MW4, MW5, MW6, MW7 and MW9 MW11 occasionally 40 contained MtBE and MW12 contained low levels of TPHg, BTEX and MtBE in the groundwater These wells will be sounded immediately before they are to be destroyed to determine whether there are obstructions that will interfere with filling and sealing If no obstructions are found these wells, the traffic box will be removed and the top of casing area will be excavated at least one foot larger in diameter than the originally drilled hole (22") to a depth of 3 feet below the ground surface The well casing shall then be cut off 6 inches above the bottom of this excavation and removed These wells will be pressure grouted with neat cement containnrig 5% bentonite The grout will be allowed to spill over into the excavation during the sealing operations, and fill the excavation for a thickness of one foot, forming a cap All fluids displaced during the pressure grouting will be collected and contained in 55-gallon drums for later disposal See Tables 1 and 2 for chemical results of groundwater and soil samples and Appendix B — Borehole and Well Construction logs Pressure Grout Monitor Well MW10 MW10 is within the new UST area and was damaged during the excavation work necessary to install the new UST's The casing was repaired by W A Craig Inc , see Appendix C This well will also be pressure grouted Prior to grouting, the protective 10" conductor casing and the 4 inch well casing will be cut at the present surface of the UST backfill (approximately 4 feet below station grade) A 36 inch diameter excavation will be dug around the casing/conductor approximately one foot below the current excavation backfill level The well and conductor casing will then be pressure grouted with neat cement containing 5% bentonite The grout will be allowed to spill over into the 36 inch diameter by one foot deep excavation during the sealing operations, • 2 R-603 site restoration WP 7-2001