ARCHIVED REPORTS_XR0007397 - Laserfiche WebLink

Home Browse Search

F r_ Fourth Quarter 2000 Ground Water Monitoring Report Cleanup and Abatement Order No.5-00-707 EAI Pro ect No. 1232 1.1.3 Robinhood Irrigation Well RIW San Joaquin Delta College owns and operates a ground water extraction well identified as the Robinhood Irrigation Well" (RIW) (a.k.a. Delta College Well), The RlW is located southwest of the intersection of Robinhood Drive and Pacific Avenue (see Figure 2). The RIW was installed in 1950 and is reported to be 322 feet deep with perforations in multiple zones beginning at depths as shallow as 40 feet below ground surface (bgs). According to the Water Well Driller's Report for the RIW, "no strata were sealed against poIlution." Fj Ground water from the RIW, which is typically operated (pump) at a rate of approximately 600 gallon per minute between May and October, was used to irrigate portions of Delta College's F'. campus. Ground water monitoring data for the Unocal and Wards sites show that pumping of the RIW influences and changes the natural direction of ground water flow in the area from easterly, to south southwesterly, i.e., towards the RIW. Sampling of the RIW by Unocal and/or Wards for dissolved petroleum constituents began in 1997 and continued through June 15, 2000. Table 1 summarizes the results of testing ground water samples from the RIW. In August 2000, Delta College students and staff complained of a gasoline odor from the water derived from the RIW. As requested by the RWQCB, the RIW was taken out of service as of 6:00 AM August 22, 2000, and can not be put back into use without prior RWQCB approval. _. 1.1.4 Cleanun and Abatement Order On September 8, 2000, the RWQCB issued Cleanup and Abatement Order No. 5-00-707 (the CAO) to Unocal, Wards, Surry California Limited Partnership, and Stone Brothers and Associates General Partnership, for the properties located at 5400 Pacific Avenue and 5606 Pacific Avenue. The CAO requested the responsible parties to investigate and clean up petroleum hydrocarbons from the former UST systems located on the Wards and Unocal sites, and stated that discharges from these two properties have impacted ground water extracted and used by San Joaquin Delta College to irrigate its campus. ' t This report has been prepared in accordance with the quarterly reporting requirements outlined in the CAO. As required by the CAO, each quarterly report shall include: • Ground water analysis results for total petroleum hydrocarbons as gasoline (TPH-G) by F 1 modified EPA Method 8015, and volatile organic compounds (VOCs), including fuel F oxygenates, e.g., MTBE, TBA, DIPE, ETBE, TAME, EDB, ethanol and methanol by EPA Method 8260B. F1 • Ground water elevation contour maps (shallow and deep). • Ground water flow diagram to document historic flow directions and magnitude. + Hydrographs for representative shallow and deep monitoring wells. 1 • Pollutant concentration contour maps for TPH-G and benzene (shallow and deep). • Tabular listing of all monitoring well details. F'- BHMAMR0092 2 ENVIRONMENTAL AUDIT, INC.,, i