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1 chlorinated aliphatic compounds using site-specific data to assess naturally -occurring reductive dechlorination processes in the perched aquifer. The results of this analysis are expected to support development of an Engineering Feasibility Study for Corrective Action. The EMP report will be prepared to summarize the methods and results of the field and laboratory investigations. It will build on the groundwater monitoring well installation report (Section 3.4), including all of the information contained therein, as well as the following: • Aquifer test field methods, methods of data analysis, and results • Groundwater sampling methods • Soil.and liquid waste management • Groundwater elevations, flow directions, gradients and velocities • Groundwater chemistry data evaluation • Assessment of migration pathways and fate of VOC impacts The EMP report will be accompanied by tabulated groundwater chemistry data and figures illustrating the locations of the existing and new groundwater monitoring wells, groundwater equipotential contours, and isoconcentration contours. The EMP report will be supported by appendices that contain the monitoring well permits, geologic logs, well construction logs, well development field data, groundwater sampling field data, chain -of - custody documentation, certified laboratory reports, aquifer testing graphical output, and Biochlor modeling output. The final report will be signed by a California Professional Geologist. The report will be submitted first in draft form for County review, then in final form after integration of County comments and edits. If the final draft is acceptable to the County, it will be forwarded to the RWQCB for their review and comment, before it becomes finalized for signature and is stamped. Prior to submittal of any work product to County, GLA will provide comprehensive senior peer review of all deliverable technical documents. 4.0 ESTIMATED PROJECT SCHEDULE Initial EMP work was conducted in a manner to meet the RWQCB schedule for submittal of the Groundwater Monitoring Well Installation Report (December 15, 2011) and the EMP Report (February 1, 2012). Samples from the temporary wells constructed during the initial phase of work contained low-level, but measurable concentrations of VOCs that require the construction of "step -out" wells to determine the extent of VOC impacts. The locations of the step -out wells presented in this revised workplan required additional negotiations between Caltrans and the County, requiring an extension to the overall project schedule. 15 2011-0115 CHSL EMP Workplan Geo -Logic Associates Revision 2 — January 11, 2012