Terraphase Soil Analysis CSA Update 2022 11 21.pdf

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Consulting Services Agreement between City of San Leandro and Last revised 11/21/2022 Terraphase Engineering, Inc for Soil Risk Analysis Exhibit A – Page 1 of 3 EXHIBIT A SCOPE OF SERVICES Project The City has a project to construct a wetland type wastewater treatment area in the former polishing pond at the west end of the existing Water Pollution Control Plant located at 3000 Davis Street, San Leandro. The former polishing ponds contain several feet of sludge which is a semi liquid material deposited from past wastewater treatment activities. Approximately 26,000 cubic yards of soil that is currently stockpiled on the sludge drying beds of the plant is available for reuse on the wetland treatment project. Consultant will characterize existing site conditions, evaluate potential regulatory risks, and conduct a feasibility evaluation for the potential use of the soil and sludge in the implementation of the treatment wetland project based on previously collected data. Consultant will review the existing available soil, sludge, and groundwater data to evaluate the potential reuse of the soil and sludge to support pending site improvement objectives. Consultant will consider the need for additional sampling, analysis, and treatability testing of soil from the soil stockpile and/or former polishing pond sludge material. Task 1 – Project Management and Meetings Two Terraphase Principals will participate in up to four 1-hour meetings (video conferences) with City representatives. Task 1 also includes project planning, scheduling, and cost tracking. Task 2 – Soil Stockpile and Sludge Data Evaluation Consultant will evaluate previous investigations and associated analytical data to determine on-site reuse implications, potential treatment requirements/options, and whether additional sampling is warranted to adequately characterize the soil stockpile and existing sludge. Consultant will base their evaluation on the following sources of data: • Soil Stockpile Sampling Evaluation, Trihydro, March 10, 2017 • Stockpiled Fill and Sludge Stabilization Study, Fugro, August 4, 2014 • Geotechnical Feasibility Study, WCPC Former Polishing Pond Equipment Pad Project, Fugro, November 2014 • Water Quality Assessment, WCPC Contaminated Soil Relocation Project, Fugro, May 19, 2016 • Preliminary Geotechnical Evaluation, Sludge Pond Closure, Water Pollution Control Plant, Subsurface Consultants, September 25, 1997 • Enthalpy analytical report, November 16, 2017 • Additional soil stockpile sampling characterization data and treatability study data generated by Leland in 2021 DocuSign Envelope ID: B65CF6DA-BB07-4010-88DC-BDA1A7ACF5A8