Laserfiche WebLink
Metadata
Document management portal powered by Laserfiche WebLink 9 © 1998-2015 Laserfiche. All rights reserved.
.r . <br /> � <br /> MAru.� <br /> cask RV0 a <br /> Working to Restore Nature <br /> isomers (BTEX) distinction using Environmental Protection Agency (EPA) Methods <br /> 5030/8015/8020. The sample from the stockpile was also analyzed for total lead. Samples <br /> were analyzed at Sequoia Analytical in Sacramento, California (California Department of <br /> Health Services Hazardous Waste Testing Laboratory Certification 1624). Copies of the <br /> Chain of Custody Records and laboratory analysis reports are presented in Appendix B. <br /> c, <br /> Results of analyses indicated TPHg and BTEX were not detected in samples from the two <br /> borings. Results of analyses are shown in Table 1. <br /> GROUNDWATER MONITORING: FOURTH QUARTER 1993 <br /> EMCON of Sacramento, California, was contracted by ARCO to conduct the field work at <br /> the site; EMCON subsequently forwarded their field notes and the laboratory reports to <br /> RESNA. Field work included measuring depths to water and collecting groundwater <br /> samples for subjective and laboratory analyses. RESNA used these data to evaluate the <br /> direction and gradient of groundwater flow beneath the site. <br /> On November 29, 1993, a technician from EMCON measured depths to water and collected, <br /> groundwater samples from wells MW-1, MW-2, MW-3, MW-5 through MW-8, and W-10 <br /> for subjective and laboratory analyses; well MW-4 was inaccessible. Floating produc or <br /> product sheen was not noted in samples from the wells (Table 2). <br /> *60 <br /> The wellhead elevations of the monitoring wells at the site were previously surveyed by Tom <br /> O. Morrow. The surveyed elevations and the depth-to-groundwater measurements, <br /> summarized in Table 2, were used to evaluate the potentiometric surface beneath the site. <br /> The groundwater flow direction on November 29, 1993, was to the east to southeast with <br /> 000 a hydraulic gradient ranging from 0.001 to 0.003 (Plate 13). The groundwater flow direction <br /> in the past has generally been towards the southeast. The groundwater elevation beneath <br /> the site increased approximately 1.1 feet since the last sampling event. Groundwater <br /> elevation data are presented on Plate 13 and in Table 2. <br /> 0.0 Groundwater samples were analyzed for TPHg and BTEX using EPA Method 5030/LUFT <br /> and EPA Methods 5030/8020. These samples were analyzed at Columbia Analytical <br /> Services, Inc. in San Jose, California (Hazardous Waste Testing Laboratory Certificate <br /> 1426). The results of analyses are summarized in Table 3. Copies of the laboratory analysis <br /> reports are presented in Appendix C. <br /> The results of analyses indicated that dissolved gasoline hydrocarbons were detected in all <br /> the wells sampled except for well MW-7. TPHg concentrations ranged from 69 parts per <br /> billion (ppb) (well MW-8) to 9,600 ppb (well MW-1), and concentrations of benzene ranged <br /> from below laboratory detection limits (wells MW-6, MW-7, MW-8 and MW-10) to 1,900 <br /> 1213cear/M3-4 3 <br /> I.r <br />