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1. PFAS Source Investigations— Preliminary groundwatertesting activities by Zone 7 did not produce data that provided any clear indication of possible PFAS sources. Therefore, Zone 7 has recently entered into contract with Jacobs Engineering Group to perform a more detailed evaluation of potential PFAS sources and recommend furtheractionsto characterize its existence in the groundwater basin. 2. PFAS Treatment — Zone 7 also entered into contract with Carollo Engineers to perform a PFAS treatment feasibility study forth eirwells. Preliminary findings indicated that Zone 7's primary focus should be on implementing IX or GAC treatment at the Chain of Lake wells. It should be noted that the Mochowells and Stoneridge well may only require operational changes as opposed to additional treatment dependenton actual regulations. 3. Preliminary Discussions on Increased Zone 7 Supply— Preliminary discussions ata staff level have occurred with Zone 7 on the abilityto offset City well water supply (i.e. water allotmentuse) with additional purchasesfrom Zone 7. The following topics for discussion were identified: • The City does not currently have a formal contract with Zone 7 forwater supply. Obtaining an offsetting watersupplywith Zone 7 would likelytrigger the need to establish a formal contract. • Additional supply from Zone would likely be groundwaterand not surface water to offset City groundwater pumping from the basin. Groundwater basin management issues such assalt removal, localized groundwater levels, and PFAS migration impacts wou Id need to be reviewed. • Meeting City supply requests at Turnout4 is already a challenge forZone 7 and they have previously expressed the desire for the City to build a pump station inthatarea. Furtheranalysis of this issue would be required with increases in Zone 7 supply. • Zone 7 has indicated thatoffsetting groundwater allotment with Zone 7 supply may have impacts to Zone 7's operation and supply purchases, as well as impacts to other retailers. Associated financial impactswould need to be reviewed that may impact fixed and variable water costs to the City. CONCLUSION Based on efforts to date, staff recommends the following: 1. The planning and design of a self -implemented PFAS treatment project should proceed for all three wells. • It is plausible that all wells will exceed future PFAS regulations. • It gives the City the most implementation control to meet a potentially aggressive regulatory schedule. • Currently, a regional treatment facility does notseem likely considering Zone 7 is focusing efforts at the Chain of Lake wells. Page 7 of 9