Agmt10 V & A Consulting Engineers, Inc.

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09-0269R 1/ ./ May 5, 2009 155 Grand Avenue, Suite 700 Oakland, CA 94612 I EXHIBIT~,1 510.903.6600 T,' I 510.903.6601 Fax i vaengineering,com ~V&A b....e1 Mr. Javier Sierra City of Redwood City 1017 Middlefield Road Redwood City, CA 94064 SUBJECT: City of Redwood City, CA . Cast Iron Pipe Water Mains Evaluation Proposal for Corrosion Engineering Services Dear Mr. Sierra, V&A is pleased to submit this proposal for the evaluation of the cast iron pipe water mains for the City of Redwood City, CA (City). The San Francisco Public Utilities Commission's (SFPUC) construction project will cross the City's water mains at 23 locations. The scope of the SFPUC project Includes exposing and removing a section of the City water main and replacing the section with PVC pipe at each crossing. As part of the City's 2004 Corrosion Control Master Plan, the City will perform a corrosion condition assessment of the exposed and removed pipe sections. The scope of the assessment has been divided into two major tasks - an in-situ pipe evaluation that will be performed prior to cutting the pipe and metal loss corrosion measurements that will be performed by V&A In the City's maintenance yard. . Corrosion rate measured on the pipe will be evaluated with the resistivity of the pipe backfill and the years the pipeline has been in the ground. Data collected during the evaluation and measurements will be tabulated and graphed for analysis and presentation. A graph of the external metal loss versus resistivity could be used by the City to estimate the external corrosion rate In mils per year of cast Iron pipes In other areas of the City and Identify pipelines for evaluation. The report will discuss how the results of the 'evaluation could be used by the City to determine remaining usefullife.of the City's cast iron water pipelines. SCOPE OF WORK Task Descriotion 1. Document Review - Review available drawings and reports for the new SFPUC pipeline and the existing City pipelines. Create data sheets for the City to use during Task 2. ;,.2. In-Situ Pipe Evaluation - The City will be responsible for performing the in-situ pipe evaluation, cutting, removing, and preserving the pipe section, replacement of cut portion of pipe with PVC pipe, and packing and sending soil samples to an analytical laboratory for corrosion analysis. V&A will be at the first excavation to discuss the requirements of the evaluation and review the test methods that will be used during the evaluation, Test procedures will be standardized and should be as consistent as possible for the duration of the project. 3. Metal loss and Corrosion Measurements - The metal loss and corrosion measurements will be performed by V&A. The City will collect and move pipe sections to a centralized maintenance or storage yard for evaluation. V&A will evaluate 5 to 6 pipe sections at a time and will perform the following tests on the 23 segments: . Photograph the interior and exterior of the pipe sections . Measure the average height and distribution of tuberculation on the pipe interior . Measure depth of external corrosion using pit depth gauge . Measure the pipe thickness using a digital caliper OAKLAND I SAN DIEGO I HOUSTON I SEAmE