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Proposal 3573 - Reservoir Inspection and Cleaning <br /> As Needed Services for Utilities – Water… (RFP #PWD-24-601) <br />City of Pleasanton <br />Page 4 <br /> <br /> <br /> <br /> <br /> April 4, 2024 <br />Scope of Services <br /> <br />Tank Dive Assessment - It is understood that the goal of this task is to complete tank <br />assessment to determine sound maintenance strategies and plans for maintaining the <br />structures. Surveys of both the internal and external surfaces of the <br />potable reservoirs will be completed. The surveys can be completed <br />with the tanks in operation. Our proposal assumes that tanks have <br />satisfactory access roads and that access to a tank exterior roofs <br />can be made from existing ladders. Underwater surveys would be <br />performed while a tank is full of water using special underwater <br />techniques and AWWA C652 sanitary procedures for potable tanks. <br />The survey will be conducted by a team of highly trained and <br />certified inspectors having exceptional diving and underwater photography skills. During the <br />evaluations, particular attention will be paid to the condition of the following critical areas: <br /> <br />Roof <br />Roof Structure <br /> Shell <br /> Tank Bottom <br />Overflow Pipe/Weir <br />Drains/Sumps <br />Inlets/Outlets <br />Piping <br />Vents/Screens <br />Shell and Roof Chine/Joints <br />Weld or Bolt Connections <br />Ladders/Safety Climbs <br />Vandal Deterrents <br />Platforms/Railings <br />Manways <br />Hatches <br />Gaskets <br />Ringwall/Anchor Bolts <br />Grade/Tank Crevices <br />Water Level Indicators <br />CP Equipment/Components <br /> <br />The focus of the inspections will be to evaluate the current condition of the interior and <br />exterior surfaces with a focus on any coating systems and the level of deterioration on a <br />tank. The evaluation will involve visual observations, but will also include applicable <br />measurements dry film thickness (DFT) measurements, adhesion testing, steel ultrasonic <br />thickness (UT) testing, pit measurements etc., where applicable. <br /> <br />Visual exterior observations will note the degree of exterior paint chalking and any breaks, <br />blisters, or other coating defects. It is not the intent of this exterior evaluation work to make <br />access to any surfaces that cannot be surveyed from the tank ladder(s) or catwalks (i.e. <br />repelling is not included within this scope). The degree of chalking will be determined in <br />general accordance with ASTM D4214 “Standard Test Method for Evaluating the Degree of <br />Chalking of Exterior Paint Films” and areas of rusting will be quantified in accordance with <br />ASTM D610 “Standard Test Method for Evaluating the Degree of Rusting of Painted Steel <br />Surfaces.” Dry film thickness (DFT) measurements will be <br />obtained in general accordance with SSPC: The Society of <br />Protective Coatings Paint Application Specification No. 2 <br />“Measurement of Dry Film Thickness with Magnetic Gages” <br />and exterior paint adhesion will be assessed using ASTM <br />D3359 "Standard Test Method for Evaluating Adhesion by <br />Tape Test, Method A” (modified) and/or ASTM D6677 <br />“Adhesion by Knife Test”. Any blistering will be quantified in <br />accordance with ASTM D714 “Standard Test Method for <br />Evaluating the Degree of Blistering Paints.” <br />EXHIBIT A <br />DocuSign Envelope ID: 127FE52A-CAEF-4879-B943-68F42EA8FF9D