ARCHIVED REPORTS_XR0007377 CASE 2

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PHASE II ENVIRONMENTAL SOIL SAMPLING AT&T MICROWAVE RELAY FACILITY 90 WEST TURNER ROAD,SACRAMENTO,CALIFORNIA CONFIDENTIAL AND PRIVILEGED labeled, and given directly to a state-certified mobile laboratory on site at the time of the drilling A chain-of-custody ' document was prepared and accompanied the samples to the on-site mobile laboratory Field characterization of soil contamination was based on visual and olfactory observations, and use of an OVM photo,- ionization detector (PID) calibrated to 100 ppm isobutylene ATC noted diesel fuel odors, staining, and elevated PID reading in boring B 1 m the depth interval from 15 to 26 feet bgs, and in boring B 10 at a depth of 12 feet bgs Soil samples were classified and logged according to the Unified Soil Classification System Soil deposits appeared ' consistent throughout the soil boring investigation (with the exception of soil boring B 1 drilled through the presumed backfill soil in the former UST excavation) Predominantly sandy gravel fill was encountered from the surface to a depth of approximately 2 feet bgs This was underlain with various thicknesses of fine to medium sand, to a depth of ' 20 feet bgs This was followed by silty fine sand to a depth of 28 feet bgs This was underlain by fine to medium sand to a depth of 32 feet bgs, the maximum depth of the borings The Soil Boring Lags are provided in Appendix B Groundwater Sampling Groundwater was encountered in soil borings B2, B3, B4, B5, B6, B7, B8, and B9 Saturated soils were encountered at approximately 26 5 feet to 28 5 feet bgs with an observed average static groundwater level of approximately 27 feet bgs Groundwater samples were collected from these eight borings from within the Geoprobe rod using a new polyethylene tube connected to a peristaltic pump The samples were collected according to ATC field procedures in 40 milliliter VOAs and amber liter bottles The samples were labeled, given directly to the on-site mobile laboratory, and logged on the chain of custody form Additionally, one water sample, Pump Water 1, was collected from a spigot within the AT&T building Two groundwater production wells located at the north and east ends of the AT&T property provided water for this tap ' Analytical Methods and Results Chemical Analysis ' ATC submitted a total of 16 soil samples for laboratory analysis Soil samples from the 10 borings and one soil cuttings drum were submitted for analysis and were tested for the following compounds Total Petroleum Hydrocarbons-Diesel fuel (TPH-D, EPA Method 8015M), Benzene, Toluene, Ethylbenzene and total Xyclenes (BTEX, EPA Method 8020), and ' Methyl Tert-Butyl Ether (MTBE, EPA Method 8020) The soil samples were collected, handled and delivered in conformance with ATC Field Procedures to a state Certified ' mobile laboratory Laboratory analyses were performed by Mobile Chem Labs, state of California DOHS certification number 1428 Soil analytical results are summarized in Table 2 — Soil Laboratory Analytical Results Groundwater analytical results are isummarized m Table 3-Groundwater Laboratory Analytical Results ATC submitted the soil samples to the laboratory, and all soil samples were prepared and analyzed within established holding times Laboratory surrogate spike samples were within acceptable ranges and the data appear to be of good quality No data qualifiers were considered necessary Certified analytical results are included in Appendix C ' 5