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• Purge at least three well casing volumes of groundwater from each well using a Waterra pump
<br /> and dedicated tubing;
<br /> • Measure pH,temperature,and electrical conductivity until the measurements are stable;
<br /> • Take a groundwater sample from each well;
<br /> • Submit samples to a California certified analytical laboratory for analysis of PCE, TCE, 1,1-
<br /> DCE, cis-1,2-DCE, trans-1,2-DCE, vinyl chloride, ethane, ethene, and methane by EPA
<br /> Method 8260B;
<br /> • Place purge water in 55-gallon drums for proper disposal;
<br /> • After the initial sampling, return to the site to collect an additional groundwater sample for
<br /> microbiological analysis of Dehalococcoides (i.e., analysis for ethenogenes) in the 3 most
<br /> impacted wells to provide data for evaluation of potential in-situ bioremediation effectiveness;
<br /> and
<br /> • Retain a licensed surveyar to survey the 17 onsite wells, the 1 offsite well,and any other onsite
<br /> wells located during the sampling event.
<br /> With results of the chemical and microbiological analyses summarized above, GES will then prepare a
<br /> draft Groundwater Monitoring Report for review by the City. With the City's comments, GES will
<br /> finalize the report for submittal to RWQCB. For budgeting purposes, we have assumed that only minor
<br /> revisions to the draft report will be needed.
<br /> Task 3—Evaluation of Remedial Options
<br /> Based on the results of the initial monitoring event, GES will evaluate a range of in-situ and ex-situ
<br /> remedial alternatives to achieve remedial objectives for PCE, TCE, and cis-1, 2-DCE in groundwater.
<br /> Remedial options may include ex-situ pumping and treatment of solvent-impacted groundwater, or various
<br /> in-situ alternatives, e.g., in-situ de-chlorination using emulsified vegetable oil (EVO) and/or zero- valent
<br /> iron (ZVI). Physical extraction of dense non-aqueous phase liquid solvent (DNAPL), if any is identified,
<br /> will be evaluated,including methods such as physical extraction and soil vapor extraction(SVE).
<br /> GES will identify a minimum of three (3) remedial alternatives to present in a Remedial Action Plan
<br /> (RAP),and will evaluate the technical,regulatory,and cost factors for each.
<br /> Task 4—Preparation of Remedial Action Plan(RAP)
<br /> With the results of Task 3, GES will prepare a RAP that describes and evaluates a minimum of three (3)
<br /> feasible remedial alternatives for the Site. A summary of the technical,regulatory,and cost considerations
<br /> for each alternative will be presented in a table. GES will recommend the preferred remedial alternative,
<br /> and will describe the steps needed for design and implementation of the selected action. A pilot test will
<br /> be recommended in order to test the feasibility of the recommended remedial alternative.
<br /> The RAP will be presented in draft form to the City for review. With the City's comments, GES will
<br /> finalize the RAP and submit it to RWQCB for approval. For budgeting purposes, GES assumes that the
<br /> City's comments will be minimal,and that no more than 8 staff hours will be required to finalize the RAP.
<br /> Task 5—Consultation,Regulatory Agency Discussions,and Project Management
<br /> GES will consult with the City via meetings, teleconferences, and e-mail, throughout the project. We will
<br /> also discuss the project status with RWQCB staff,and will coordinate with Regency Centers on Site access
<br /> details and performance of Site work, as necessary. For budgeting purposes, we have assumed that one
<br /> meeting will be held with the City,and one meeting with RWQCB staff.
<br /> We have also assumed that GES will be provided a copy of the executed Access Agreement with Regency
<br /> ATTY/AGR/2014.174/GROUNDWATER&ENVIRONMENTAL SERVICES
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