Laserfiche WebLink
MMMIMM <br /> LATHROP PROPERTY <br /> WKA No. 1184.02 <br /> # January 30, '1992 <br /> Page 9 <br /> uncontrolled aeration. Ali Othman with the Sari Joaquin.County Air Pollution Control District F <br /> concurred with our determination and authorized us in February, 1991,to proceed with soils <br /> aeration in accordance with the'applicaton,thatwe submitted to,his office. i <br /> The stockpiled soils were subsequently spread on construction grade polyethylene across an <br /> approximate 18,800-square-foot area for aeration. Only 28 cubic yards of soils, owaver, +' <br /> were aerated at any one time;the remaining contaminated soils were kept covered until each <br /> 1 s <br /> %25-cubic-yard-unit appaardd, based on visual and olfactory field observations, to have <br /> completely aerated. <br /> .,Q After it appeared that all the aerated soils had been successfully remediated, the entire <br /> aeration area was divided into a sampling grid. A total,of 28 samples were obtained from the <br /> ° aeration,arm,22 of.which.were collected September 3,'.1991, six aeration arae.locations <br /> `B were rc?.+'6inpled ori Jctober, 17; 1991. The samples were composited at the rate of t_wo--into- <br /> one by:tha laboratory"prior„to analysis for TPH and BTX&E" <br /> L �' We reviewed the analytical test results and field activities pertaining to the aeration of <br /> petroleum hydrocarbon contaminated soils excavated from the property and anticipated that <br /> remediation was successful. Mr. Othman issued a November 8, 1991 latter entitled <br /> "Fulfillment of District Rule 409.9 Requirement for Uncontrolled Soil Aeration at 91 E. <br /> Thomsen Road,Lathrop"; we have included this letter as Appendix B. <br /> Via <br /> Ground Water Investigation } <br /> i <br /> We installed three ground monitoring wells (WI through W3; Plate 2)'in the vicinity of the: <br /> southwesterly Y corner o.f_the `subject property'on Septernber 3; 19. 9,: 'Subsequent to 'a <br /> decision among CVRWQCB and SJCPHS personnel that oversight of environmental activities s <br /> t pertaining to the property would he provided by the local agency, our Workplan for Soils <br /> ivs <br /> Remediation/Ground Water Investigation was verbally approved on December 21, 1990. <br /> I r Well location Rationale <br /> !moi <br /> The property is located in an area of ground water indicated to flow to the north-northeast, <br /> �+ as previously discussed in the Geologic and Hydrogeologic Setting section of this report. We <br /> i <br /> t WALLACE•-KUHL <br /> Er ASSOCIATES tNC. _ <br />