ARCHIVED REPORTS XR0008506 - Laserfiche WebLink

Home Browse Search

April. 1987 - The 3 tanks were removed and soil samples taken. ' Laboratory analysis of samples from beneath the gasoline tanks were below detection limits, but the soil sample from the waste oil site revealed the presence of ethylbenzene, toluene, xylene, TPH--G, & motor oil. Refer to TABLES i_& II for details. June 19g7 - Site of removed waste oil tank was deepened to about 8 1/2' with a backhoe. A sample was taken at that depth and ' analyzed for TPH; gasoline was measured at 1500 mg/kg, & motor oil at 4200 mg/kg; diesel & kerosene were below detection limits. Refer to TABLE III for details. ' August- 1987 - Waste oil tank site reentered & deepened to 13. 5' under direction of the EHD. A soil sample taken at that depth was analyzed for benzene, toluene, xylene, & TRPH. Motor ' oil was measured at 3100 mg/kg; all others were below detection limits. Refer to TABLE_ IV for details. ' October, 1989 - Site was reentered & soil sample taken at approximately 23' below grade. Laboratory analysis showed that oil, as motor oil, was present at 280 mg/kg. This work was not witnessed by the County EHD- August, 199 HD_August, 1993 - Correspondence from County EHD required additional work to define limits of contamination_ ' September_=_ 1993 - Workplan submitted by Wm J. Hunter & Assoc , (WJH, ) to place four (4) 30 foot deep soil borings. Refer to the ' PAR, dated January 4, 1994, prepared by WJH, for a copy of that workplan. October 27 & 28 1923 - work was performed under the direction of ' Wm. Hunter, RG, using Spectrum Exploration auger rig & personel Refer to the above referenced SAR for a detailed description of that work. TABLES V V & VII show the results of laboratory ' analyzes from soil samples taken during the placement of the soil borings. Those analyzes revealed that ALL samples were either below detection limits, or within acceptable levels, for Chlorinated solvents, (EPA 8010 , ) ICAP metals, & TPH--D. BTEX & ' TPH-G were below detection limits in all samples except soil boring #2 at 36' . ' Januarg. 1994 - A report entitled "PROBLEM ASSESSMENT REPORT COVERING SOIL CONTAMINATION INVESTIGATION" , was prepared by WJH & submitted to the San Joaquin County EHD covering the field work ' conducted in October, 1993, and discussing the results. February 28 1994 - Correspondence from San Joaquin Co. EHD recommended further assessment and/or re-excavation of the former waste oil tank site. A copy of that letter is included as ' 3