|
' • • Fla Ci Shell#1003
<br /> Site History& Background g t
<br /> New West Stations 6437 West Banner Street, Lodi, California
<br /> In June 2006,the RWQCB-CVR became the lead oversight agency for the Site.
<br /> ' On July 17, 2006, Apex submitted a Time Schedule to Complete Corrective Action in response to the
<br /> CRWQCB letter dated July 7, 2006.
<br /> On July 17 through 21, 2006,Apex personnel supervised the drilling, sampling and installation of one on-
<br /> Site groundwater monitoring well (MW-3C) and seven off-Site monitoring wells (MW-4C, MW-7A, B,
<br /> ' MW-8A, B and MW-913, C). An additional off-Site deep-zone well (well MW-913) was installed on July
<br /> 31,2006. All soil samples were below detection limits for all constituents except MTBE, TAME and total
<br /> lead. MTBE was detected in all samples collected in wells MW-3C and MW-713 with highest
<br /> ' concentrations at 30.5 feet bgs in well MW-713. The only detection of TAME was at well MW-713, at 30.5
<br /> feet bgs. Second quarter groundwater samples and groundwater samples collected from new wells after
<br /> ' installation showed MTBE detected at all first-zone wells except wells MW-1, MW-5A and MW-8A.
<br /> MTBE was detected at second-zone wells MW-313, MW-413 and MW-613 through MW-813, but was non-
<br /> detect at wells MW-513 and MW-913. Of third-zone wells, MTBE was detected only at well MW-3C.
<br /> ' MTBE was not detected at forth-zone well MW-9D. All other analyzed constituents were non-detect.
<br /> On December 5, 2006, Apex submitted a report entitled Groundwater Monitoring Well Installation
<br /> ' Results Report documenting the installation of these groundwater monitoring wells.
<br /> On September 6, 2006,Apex performed startup of a pump and treat system for groundwater remediation
<br /> ' in the presence of two representatives from the RWQCB-CVR. The groundwater extraction system draws
<br /> water from the upper water bearing zone from wells EW-1 through EW-5.The groundwater extraction
<br /> ' system consists of three 1,000 Ib LGAC vessels linked in series, as well as an Air Stripper and one 1,000
<br /> lb VGAC vessel to treat off-gasses. As of First Quarter 2007 a total of 0.84 pounds (lbs) of TPHg and
<br /> 99.1 lbs of MTBE had reportedly been removed from the subsurface. Apex received an Authority to
<br /> ' Construct No. N-7510-1-0, from the San Joaquin Valley Air Pollution Control District on September 9,
<br /> 2006 to operate the air stripper related to the water treatment system.
<br /> ' On November 1, 2006, the RWQCB-CVR issued a draft Cleanup and Abatement Order(CAO) with a 20-
<br /> day review period for comments. On November 20, 2006,Apex submitted comments to the draft CAO.
<br /> ' On December 1, 2006, Apex submitted a request to the RWQCB-CVR to install a Glacier Laboratories
<br /> scale and deposit control system on the water treatment system. The RWQCB-CVR subsequently
<br /> approved the request, and the anti-scale water treatment system was installed.
<br /> ' On April 30, 2007, the RWQCB-CVR issued Cleanup and Abatement Order No. RS-2007-0709 for the
<br /> ' Site. The Order directed the performance of additional Site investigation activities (including further
<br /> delineation of the groundwater plume and evaluation of vapor intrusion potential), the preparation of a
<br /> Risk Assessment, and off-Site remediation.
<br /> ' On May 8, 2007, Closure Solutions became the Consultant of Record for the Site. As a result, APEX
<br /> removed the Air Stripper, two 1,000 lb LGAC vessels, one 1,000 Ib VGAC vessel, and the associated
<br /> ' anti-scale system. Closure Solutions submitted a Remediation System Modification and Sampling
<br /> Schedule dated May 22, 2007 proposing the implementation of two 2,000 Ib LGAC vessels in lieu of the
<br /> ' Page 4 of 7 Closure Solutions, Inc.
<br />
|