ARCHIVED REPORTS XR0000297 - Laserfiche WebLink

Home Browse Search

FIELD REPORT QUARTERLY GROUNDWATER MONITORING SAN JOAQUIN COUNTY MOSQUITO ABATEMENT DISTRICT LODI FACILITY, LODI, CALIFORNIA On January 26, 1993, ROY F. WESTON, INC. (WESTON) conducted groundwater sampling at the San Joaquin County Mogquito Abatement District (SJCMAD) facility at 200 North Beckman Road, Lodi, California This field work has been performed to meet the requirements of the San Joaquin County Public Health Services, Environmental Health Division (EHD) letters dated June 7, 1991 and February 10, 1992 Upon arrival at the site, the standing water levels and total well depths were measured in all monitor wells using an electronic well sounding device MW-2 and MW-3 were dry The elevation of groundwater relative to Mean Sea Level (MSL) in MW-1 and MW-4 was calculated and the results are presented in Table A-1. ' TABLE A-1 Water Level Elevations January 26, 1993 Well Location Top of Casing Elevation Total Depth Depth to Water Water Elevation (feet, MSL)' (feet) (feet) (feet, MSL) MW-1 54 11 550 5453 -042 MW-2 5428 528 Dry Dry MW-3 5403 51 5 Dry Dry MW-4 5443 695 5778 -3 35 Due to the very low water level in MW-1, sampling was not feasible For MW-4, only the water level measurement and total well depth were used to calculate the required purge volume for the well A clean submersible pump was used to purge MW-4 and the discharge rate was measured in order to calculate the time required to obtain three casing volumes MW-4 was purged over three casing volumes (23 gallons) and the well was allowed to fully recover prior to sampling At the beginning, during, and end of the purge process, the purge water pH, electrical conductivity, and temperature were measured This information was recorded on field water sampling data sheets and final values are presented to Table A-2 9[hCIRPTSVSICMAI}1 WP A-1 M125/93