21 - Laserfiche WebLink

financial plan for the entire Project is being developed and will be presented to City Council at a future meeting. BACKGROUND PFAS are a large group of man-made substances that have been extensively used since the 1940's in common consumer products designed to be waterproof, stain- resistant, or nonstick. In addition, these substances have been used in fire-retarding foam and various industrial processes. PFAS are unregulated contaminants of emerging concern in drinking water due to their health impacts and tendency to accumulate in groundwater. Perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are the most studied substances and are the focus of initial regulatory efforts in California. DDW has provided a tentative schedule to regulate PFOA and PFOS by establishing draft MCLs by fall of 2022 and final MCLs by early 2024. DDW has also started the process of reviewing other PFAS for possible regulation, but a schedule has not yet been identified. The City began testing its groundwater for PFAS the second quarter of 2019 in compliance with general orders issued by DDW to numerous water agencies. Test results have shown that the City's Wells 5, 6, and 8 groundwater supply facilities contain the presence of PFAS. Well 8 contains the presence of PFOS above advisory levels and as a result has not been operated since June 2019. On September 1, 2020, City Council supported a work plan to address PFAS that: • Prioritizes efforts on advancing the planning, design, and construction of self- implemented PFAS treatment at City wells. • Explores regional alternatives with Zone 7 on a parallel path. To begin the process of self-implemented PFAS treatment, the City established CIP 21166 - PFAS Treatment and Wells Rehabilitation Project (Project). The goal of the Project is to extend the useful life of Wells 5, 6, and 8 as safe, reliable, and locally controlled sources of water for the City by: • Implementing a PFAS treatment system that can reduce concentrations to meet the City's low-treatment goal (defined as the consumer confidence report detection levels listed in the current DDW Order DW-2020-0003-DDW). • Rehabilitating the well facilities to extend their useful life by 30 years to be comparable to the useful life of a new PFAS treatment system. • Allowing for expansion of the PFAS treatment system site to accommodate potential future water treatment regulations. DISCUSSION The City entered into agreement with Carollo in September of 2020 to prepare a Basis of Design Report (BODR) for the Project. The purpose of the BODR is to establish the scope of the Project and serve as the basis for final design. Carollo has completed the Draft BODR, which can be found at the following link: Draft BODR (available June 9, 2021). The Executive Summary from the Draft BODR is included as Attachment 1. Below highlights the recommended Project scope: Page 2 of 4