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Project No 014-95262 Page No 9 7.2.5 Treatment Plant Clarifier and Sump Soil borings KB-5 and KB-6 were advanced as close as practicable to the below-grade clarifier and sump, respectively, as a check on potential leakage Nitrate, phosphate, and ammonia were not detected where analyzed for these constituents Chloride and EC were at or near background levels pH was slightly below background (7 1 in both borings) 7.3 CPT Sgundl= Cone Penetrometer Test (CPT) soundings were conducted at six locations The purpose of the soundings was to better define the soil profile at other portions of the site and to define more permeable zones for later Hydropunch® (or equivalent) sampling # 7.3.1 Description of Method and Data The cone penetration test involves hydraulically pushing a cone-shaped instrument into the soil and measuring its resistance to penetration Resistance is measured by sensitive stram gauges on the instrument that transmit electronic signals to an automatic data logging system Plots of the data provide continuous ! logs similar to electric logs familiar to those in the oil and water well industry The logs generated from CPT soundings at the Safeway site are presented in Appendix C Also included is the tabulated data from which the logs were generated The data collected include tip resistance (Qc), sidewall friction (Fs), inclination (1), and pore pressure (Pw) Data is acquired at a rate of 2 cm/sec with measurement increments of 5 cm Based on the relationship of Qc, Fs, etc , the data allow an interpretation of soil type penetrated (refer to tabulated data in Appendix C) When reviewing the graphic logs, in general, sandier units are defined by increasing Qc and Fs On the graphic logs in Appendix C, this is represented by "fingers„ pointing toward each other on the two left-most logs on each page 7.3.2 Soil Profile A review of the graphic logs and soil type interpretation on tabulated data shows that the soil profile is dominated by finer grained units to the maximum depth investigated at 51 feet bgs Thin, yet distinct, sandier units are present throughout the profile The units were commonly noted at the surface (fill),at 4 to 5 feet bgs and 12 to 15 feet bgs Data from the 15 to 30 foot zone show more coarse grained material than that above this interval and may correlate to the siltier units noted on exploratory soil boring logs Below 30 feet bgs a thicker, sandier unit was evident on most logs Many CPT soundings were terminated at this depth as it was assumed from review of pore water pressure and penetration resistance data that the unit would be favorable for collecting groundwater samples Based upon the existence of the KRAZAN & ASSOCIATES, INC Offices Serving the Western Unrted States 95262 Piz