Laserfiche WebLink
CHRONOL <br /> UNOCAL / TOSCO #5417 . <br /> 1700 E. YOSEMITE ROAD <br /> (HIGHWAY 120 @ HIGHWAY 99) <br /> MANTECA CA-, 9 336 <br /> LOP-35.27 SITE CODE: 507794 / CR#588 <br /> 12/19/97 PHS-EIHD receives corrective action plan wid papers for Public Participation (PP) <br /> for over-excavation at time of piping liner placement. <br /> 01/05/98 PP two-day period due to rush job and no ensitive concerns around site. PP closes <br /> 1/7/98 at 5pm. <br /> i <br /> 01/14/98 PHS/EHD staff witnesses soil sampling at each end of two islands. Soil samples <br /> "PD-1 @ 2' "has strong petroleum odors d stained gray sandy soils. Over- <br /> excavation to 5/5.5 ` bgs with sod samples at bottom. Similar for three of four <br /> dispensers also. Soil appears to clean up wth depth and odors decrease. Pacific <br /> Environmental Group (PEG) field technician Jessica Nelligan advises Ed Ralston of <br /> obvious soil contamination and Ed to subruk Unauthorized Release Form (URF) <br /> with this date. <br /> 01/16/98 Tosco faxes URF. Prop 65 completed for oil contamination. Database/MFR <br /> completed for site. <br /> 01/27/98 "Soil Oras Survey Results" report received today from PEG and dated October 29, <br /> 1997 and done without PHS-EHD notifica don or permit(s). <br /> 03/28/98 . Site officially enters LOP as soil site <br /> 04/09/98 Review of"Soil Sampling Results for Static n Upgrade", dated 4/6/98 as submitted <br /> by PEG. Four areas (end of each island) sampled at 2' bgs and three of these areas <br /> over-excavated and sampled again at " 5'b gs. All soil samples record TPH-G hits <br /> from low of 28 mg/kg at "PD-2 @ 5.5'bg " to high of 15,000 mg/kg at "PD-1 @ 2' <br /> bgs". Benzene ND in four of seven sampl s to high of 20 mg/kg in "PD-1 @ 2' <br /> bgs". "PD-1 @ 2' bgs over-excavated to 5 bgs and still records TPH-G at 12, 000 <br /> mg/kg and Benzene down to <a005 mg/Ig. NO groundwater samples taken <br /> during this phase. Comment letter require a groundwater investigation and work <br /> plan due by June 19, 1998. <br /> 06/30/98 Work plan received and reviewed. <br /> 07/09/98 Comment letter sent Requires five oxygenates to be sampled for in soil and <br /> groundwater by EPA Method 8260. Ethanol and Methanol to be analyzed by <br /> 8015m. Advises of historical depth requirement and indicates 25'bgs is depth of <br /> concern. Additional deeper soil samples needed if 25'bgs has hits. Work plan <br /> approved with conditions and requires GE DPROBE work to start before July 31, <br />