|
r
<br /> WASTE DISCHARGE REQUIREME*10RDER NO R5-2012-0105 -2-
<br /> GLENN SPRINGS HOLDING COMPANY,
<br /> FORMER OCCIDENTAL CHEMICAL COMPANY, GROUNDWATER REMEDIATION PROJECT, LATHROP FACILITY
<br /> SAN JOAQUIN COUNTY
<br /> effluent limits based on the best available technology for treatment, and allow for
<br /> injections above the Corcoran Clay.
<br /> 5. The Site is located within the City of Lathrop, San Joaquin County, California near the
<br /> intersection of Louise Avenue and Howland Road (See Attachments A and B). The Site
<br /> occupies approximately 340 acres, most of which is paved or covered with buildings.
<br /> The Site is underlain by relatively flat-lying unconsolidated silts, sands, and clays to a
<br /> depth of approximately 230 feet bgs.
<br /> 6. The Site includes Assessor's Parcel No. 198-180-01 , 02, 03, 04, 05, 06 and
<br /> 198-140-03, and 04.
<br /> 7. Surrounding land uses include agricultural, industrial, and residential.
<br /> 8. Mean annual precipitation at the Site is 14 inches. Mean annual pan evapotranspiration
<br /> from the nearby Tracy pumping plant is 97 inches.
<br /> 9. The City of Lathrop operates a municipal water system with wells located approximately
<br /> 2,000 feet west and northwest of the Site, and approximately 3,000 feet to the south.
<br /> These water supply wells are sampled semi-annually by the Discharger and analyzed
<br /> for Site CDCs.
<br /> Project Layout and Operation
<br /> 10. The Site has been owned and occupied by the J.R. Simplot Company (J.R. Simplot)
<br /> since 1 January 1983. The location and orientation of the Site is shown on
<br /> Attachment B. J.R. Simplot currently owns all the land comprising the Site, and all the
<br /> improvements to that land except the groundwater remediation system (including the
<br /> treatment plant, monitoring wells, extraction wells, injection wells and associated
<br /> infrastructure) that were installed by the Discharger. The Discharger is responsible for
<br /> mitigation, cleanup, and abatement of any contamination of groundwater attributable to
<br /> operations at the Lathrop facility that occurred prior to 1 January 1983.
<br /> 11. The current groundwater remedial system extracts groundwater from up to ten (10)
<br /> extraction wells (EW-02, EW-03, EW-04, EW-04A, EW-05, EW-06, EW-07, EW-8A,
<br /> EW-8B, and EW-09). Extraction well EW-01 was removed from service in _1995 due to
<br /> low concentrations of COCs. Extracted groundwater is treated using a bioreactor and
<br /> granular activated carbon (GAC), and then disposed of by injection into two deep wells
<br /> IW-01 and IW-02.1hat are completed in the confined aquifer beneath the Corcoran Clay.
<br /> 12. The Discharger has proposed to add eleven (11) additional extraction wells: EW-10,
<br /> EW-11, EW-12A, EW-12B/C, EW-13, EW-14A, EW-14B/C, EW-15A, EW-15B/C,
<br /> EW-16, and EW-17 to accelerate cleanup of sulfolane, DBCP, and EDB in groundwater
<br /> beneath the Site. Additional extraction wells may be added if needed under subsequent
<br /> phases of work with written approval from the Central Valley Water Board.
<br />
|