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includes the area extending 50 feet on either side of the Former Shell Central Valley <br /> Crude Oil Pipeline easement("Limited Area'). <br /> This SMP describes the environmental assessment and remediation activities conducted <br /> by SHELL at Cordes Ranch. It also outlines the process by which SHELL will respond to <br /> the discovery of soil impacts ("Affected Soil") originating from the Former Shell Central <br /> Valley Crude Oil Pipelines. <br /> A summary of previous work performed at the site and additional background <br /> information is presented in Appendix A. <br /> 2.1 SUMMARY OF SITE CONDITIONS <br /> • Soils beneath the site consist of primarily of unconsolidated alluvial deposits that are <br /> predominately fine-grained clayey silts and silts. Discontinuous coarse-grained <br /> horizons occur at varying depths and thicknesses in the shallow zone (A) and to a <br /> lesser extent in deeper zones (B and C). All Zones (A, B, and C) occur within the <br /> regional shallow semi-confined water-bearing zone. <br /> Depth Interval Depth to Groundwater Groundwater Elevation Typical Groundwater Flow <br /> zone fb Range ftb s Range ft MSL Direction <br /> A 10 to 50 31.84 to 38.65 85.60 to 88.79 North-Northeast <br /> B 105 to 125 24.63 to 36.63 83.84 to 92.79 Northwest <br /> C 160 to 177 50.99 to 57.56 63.30 to 67.81 East <br /> ft bgs=feet below ground surface;ft MSL=feet relative to mean sea level <br /> • Based on the available information, groundwater will not be used for beneficial use. <br /> The City of Tracy General Plan (Section 11.04.160) declares use of water wells as a <br /> public nuisance, and requires connection to City-supplied water if premises are <br /> within 200-feet of a City water supply pipeline. The development plan includes <br /> build-out of the City water supply system to all areas of Cordes Ranch. <br /> • In soil, benzene, toluene, ethylbenzene, and xylenes (BTEX) are substantially <br /> non-detect and at low concentration where detected. Overall, TPHc impacts in soil <br /> along the pipeline section of interest as a whole have been adequately delineated, <br /> except northwest of B-109 and near MW-15. A work plan to delineate these areas <br /> was submitted to the RWQCB on March 7, 2014. The historical soil analytical data <br /> indicates that there are discrete locations with Total Petroleum Hydrocarbons as <br /> crude oil (TPHc) in soil along the 2-mile pipeline section of interest. The results also <br /> 060223(33) 2 CONESTOGA-ROVERS&ASSOCIATES <br />