ARCHIVED REPORTS XR0012540 - Laserfiche WebLink

Home Browse Search

k is 1— .WA r� !Aldo:;vard•Ciyde Cortsuftrr'ds water, i.iple rinsed with tap water, Wen rinsed with distilled water. The augers were steam elerned prior to'and between each boring. The boring lass are presented in Appendix A. The cuttingrs from the borings were Placer; in tye soil stockpiled from the gasoline tank removal operations. r� Monitoring wells were installed in each of the three borings. The wells were constructed with 2-inch diamet:r schedule 40 PVC piping, slotted over the bottom 15 feet. The wells were installed to a total depth of 90 feet ,10 feet below the groundwater surface). A typical monitoring well c;astruction is shy-,—a on Figure 3. The sampl;,s were submitted to WCC analytical laboratory located in Pleasant Hill, California under chain of custody. Three soil samples from each boring were selecteei for laboratory analysis based on the VOC concertration and on visual observation of the soil conditions. The soil -Amples selected for analysis from each Loring were as follows: 1. the soil sample collected above the groundwater interface, 2, the soil sample with the highest VOC concentration above sample I, and 3. a soil sample with a low VOC concentration above sample 2. x The samples were analyzed for TPH (gasoline) by EPA method 8015, BTEX by EPA meCiod 8020/5030 and total lead concentration by EPA method 7241. The soil samples selected for analyses were at depth intervals of 26.1-26.5 fit,51.1-51.4 feet and 74.6-75.0 E ` feet in MW-1;at depth intervals of 40.1-40.5 feet,50.6-51.0 feet and 75,6-76.0 feet in MW- 2, and 41.1-41.5 feet, 55.6-56.0 feet and 75.6-76.0 feet in MW-3. 2.2 GROUNI3WATER INVESTIGATION y Groundwater samples were collected by WCC on Augm:20, 1991 from the three monitoring wel!s(MW-1,MW-2 and MW-3). Prior to sampling, each monitoring well was sounded to determine the distance from the top of the "Christy" box to groundwater and to determine the thickness of free product(if present). The wells were developed and purged prior to 6ICO231A.lM/:aRMART.WP IM-911FQ.8 2-2 ill.