ARCHIVED REPORTS XR0009405 - Laserfiche WebLink

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i Soil&Cavadon Following laboratory analyses of samples on-site, some soil �' f determined to be contaminated may be excavated and stockpiled if the contamination is localized and easily accessible. If soil contamination is found to be wide spread or otherwise involves the excavation of an inordinate amount of clean soil to access i contaminated soil, then no further soil will be excavated. In no case i will more than 2500 yards of soil be excavated. Clean soil will be segregated from contaminated soil. No additional excavation on the {' west side of the excavation is anticipated at this time in order to avoid causing possible ground instability in El Dorado Street. I &H S=per { Soil samples will be taken at 5 foot intervals, or at significant. lithologic changes in the soil, beginning at 5 feet below the ground + ' surface. All samples will be examined in the field for evidence of ,r contamination. Examination will include visual observations, detections of odor, and readings from a photoionization detector (PID). Selected soil samples will be submitted for immediate laboratory analysis in an on-site mobile laboratory. Samples for .; immediate analysis will be selected for purposes of determining if t groundwater has been impacted and to confirm clean zones. Soil samples exhibiting obvious staining or odors will either not be analyzed or will be analyzed later to confirm contaminated zones. Soil borings will be made by a mobile truck mounted drill rig using :. hollow stem augers. Soil samples will be taken with a California modified split-spoon sampler fitted with brass tube liners. i All brass liners will be steam cleaned prior to use. All augers, bits, ' and split spoon samplers will be steam cleaned prior to beginning work and between all borings. Soil samples will be collected by inserting the augers sampler into the au p g and hammering it into the soil to the desired depth. The sampler will then be removed from the augers and the brass liner containing the sample will be removed from the sampler. The soil sample will " I be examined for evidence of contamination. Any brass tubes containing samples exhibiting evidence of contamination will be covered with Teflon tape and capped with plastic caps to make airtight seals. The brass tube will be labeled with the boring number, i sample interval depth, sampler's initials, date, time, location, and analysis required. The sample will be logged on a chain-of-custody I form and in a field book, and noted on the boring log. (A sample Chain-of-Custody form is shown in Appendix C. A sample boring log K, is shown in Appendix D.) The sample will be placed in a water-tight plastic bag and stored in a cooler containing ice. Once all the t i 2-3