ARCHIVED REPORTS_XR0005211 - Laserfiche WebLink

Home Browse Search

GROUNDWATER MONITORING REPORT USA PETROLEUM - STOCKTON #110 JULY, 1995 ' 2.2 Monitoring Well Purging Each monitoring well was purged by pumping , at least three well volumes of water ' Temperature, pH and conductivity were monitored while purging the wells, and recorded on field data sheets, which are maintained in our office The wells were allowed to recharge to at-least 90% of their initial static water level prior to sampling Groundwater purged from the wells was ' placed in appropriately labeled DOT approved 55-gallon drums The drums will be disposed of using proper methods and protocol after the analytical results are reviewed A summary of field data is presented in Table 2, and copies of the field data sheets are included in Appendix A 2.3 Groundwater Sampling ' Each groundwater sample was collected using a new Teflon disposable bailer The sampled water was placed to laboratory prepared sterile 40 nultditer glass, one liter plastic, and one quart amber containers The sample containers were filled to the top to expel air space and were sealed with ' Teflon-lined caps Water sample containers were labeled with the name of the sampler, the date, the lob number, the preservative, and an idenhfytng number The samples were then transported to Sierra Laboratories(Sierra), to Anaheim, California, a state certified laboratory Full chain-of- custody(COC) protocol was followed during sample handling and delivery 2.4 Groundwater Analyses Analyses of the groundwater samples were performed by Sierra in accordance with state guidelines and EPA protocol The samples were analyzed for TPH G, TPH D, BTEX, and total lead using EPA methods 8015, 8020 and 239 2 , respectively ' 3.0 SUMMARY AND CONCLUSIONS ' 3.1 Results of Groundwater Laboratory Analyses Detectable levels of petroleum hydrocarbons as gasoline were reported in monitoring wells ' MW-2-P and MW-3-P at 250 parts per billion (ppb) and 510 ppb, respectively No detected levels of petroleum hydrocarbons as diesel were reported in any of the wells BTEX compounds were all below the detection limit of 0 5 ppb in MW-1-P Benzene values ranged from 13 ppb in MW-3-P to 11 ppb in MW-2-P Toluene was detected at 0 64 ppb in MW-2-P and 3 8 in MW- 3-P Only MW-2-P had any detectable levels of ethylbenzene The reported concentration in MW-2-P was 2 8 ppb No detectable levels of total lead were detected in MW-1-P and MW-2-P 2