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IX essentially exchanges the PFAS ion that is in the water with one that is inert and while the treatment media is more expensive, less of it is needed. Utilities Planning Manager Yamello provided a brief overview of the Treatment Life-Cycle costs between GAC and IX and noted the Operation and Maintenance costs increase significantly between High, Medium, and Low. He noted key assumptions include dedicated treatment at Well 5, 6, and 8, understanding the High Treatment Goal requires treatment at Well 8 only, the vessels would be outdoors and cost does not include a building, does not include well R&R improvements, and the Net Present Value (NPV) is based on 30 years. Lastly, he reported the key conclusion is Capital costs are not impacted by goal selection for Medium and Low Treatment Goals, and Operations and Maintenance costs vary primarily due to media change-out frequency. Utilities Planning Manager Yamello reported Well 5 and 6 have challenges and noted operational access is extremely tight and there is minimal room to expand for future treatment. He advised public outreach, California Environmental Quality Act (CEQA)/permitting processes may present a schedule risk due to the complications of the site being near a residential area along with visual impacts to nearby residents. Lastly, he advised if the vessels were placed in a building it would require an additional $2 million in funding and increase the implementation challenges. Utilities Planning Manager Yamello reported Well 8 has good operational access, room to expand, minimal visual impacts due to location, building likely not needed, and has a simplified public outreach and CEQA/permitting processes. He noted the Operation Service Center is currently a multi-use area that would then need to be dedicated to permanent water use to the investment. Utilities Planning Manager Yamello explained consolidating PFAS treatment at Well 8 site can eliminate concerns associated with the Well 5 and 6 site. He noted it would require the construction of a pipeline from Well 5 and 6 to the Well 8 site and a return pipeline may be needed. He advised the pipeline would cost $3 million and the return pipeline would cost $2 million. He explained some additional benefits would include consolidation of chloramination and fluoride dosing to Well 8, removal of chemicals from Well 5 and 6, and a phased PFAS treatment installation can be supported while maintaining well pump redundancy. Utilities Planning Manager Yamello reported on Zone 7 activities and advised they are in contract with Jacobs Engineering Group to evaluate PFAS sources and recommend further actions by the end of the year. He advised Zone 7 has been in contract with Carollo Engineers to perform a PFAS Treatment Feasibility Study, noted their primary focus is on implementing IX or GAC treatment at the Chain of Lake Wells but are hoping to not do treatment at Mocho and Stoneridge Wells. He believes Zone 7's board will recommend there is no financial benefit to try and do a regional treatment at their next board meeting. He advised preliminary discussions with Zone 7 identified the need for a formal contract.. identified that the additional supply would be groundwater and the impact would need to be evaluated, identified supply challenges at T04, and identified financial considerations due to impact to Zone 7 operations and supply purchases. Utilities Planning Manager Yamello reported the staff recommendation is to proceed with planning and design of self-implemented PFAS treatment at all three wells and recommends basing it on the Low Treatment Goal, using an infrastructure and site spacing design that allows the use of IX or GAC, and include space for treatment expansion for other potential contaminants of emerging concern. He noted the next steps include performing a Bases of Design Report (BODR) and continuing to explore regional solutions and monitor variables that may impact the work plan direction. He advised staff is recommending an agreement for $437,374 with Carollo Engineers to prepare the BODR. In response to Councilmember Testa's inquiry, Utilities Planning Manager Yamello reported PFOA and PFOS are no longer being manufactured. He clarified the current regulations are looking at PFOA and City Council Minutes Page 4 of 9 September 1. 2020