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GScope of Work Background and Assumptions: • Well 26 production capacity is <2,000 gpm. • Well 26 currently pumps to the 38-foot maximum water level in the existing 6.0 MG East Reservoir (a ground level steel tank). • A sand separator will be installed on the existing well discharge. • A 12-inch connection to the existing 12-inch by-pass around the north end of the 6 MG East Reservoir will be used to direct the well production to the treatment system. • Two horizontal cartridge filters will provide pre -filtration for the IX treatment vessels. • One train of 12-foot diameter lead -lag IX vessels and appurtenances. • IX flush water supply (FWS) needed for change -outs to be de -chlorinated. • IX flush water waste (FWW) disposal to existing storm drain or sewer. Survey of flow line elevations to verify sufficient fall to drain, by others. • A new in -line booster pump station with two 75 to 100 HP outdoor pumps (1 duty and I stand-by) equipped with VFDs will boost the well production through the pre -filters and IX pressure vessels. • No new buildings are required since the existing 15'4" x 18'8" Control Building is large enough for the old MCC, Electrical Panels, and SCADA equipment to be replaced and air conditioning added for the new VFDs. • The treated effluent from the lag IX vessel will return in a new 12-inch pipeline to the existing 12-inch reservoir inlet. • To satisfy the CA Division of Drinking Water (DDW) requirements, a spool section of the existing 12-inch well discharge to reservoir inlet will be removed forcing well production through PFAS treatment before entering the reservoir. • It is assumed that the building adjacent to Well 26 is a chlorine storage and feed building and the small building to its east is an ammonia building, both added since the 1968 reservoir construction. Thus, chlorine and ammonia will be added to the PFAS treatment effluent through a new static mixer with chemical injection lines. • Associated facilities will include an emergency generator with automatic transfer switch to serve Well 26 and the PFAS treatment system. • Survey and geotechnical investigations are excluded from EEC's Scope of Work. • Bid assistance and services during construction are excluded from this Scope of Work. • The Planning Study does not include wells previously included in the Santa Ana Producer Report. Wells previously included in the Producer Report can be included with expanded studies at an additional cost, if requested. Task 1- Planning Study OCWD's consultant completed a PFAS Treatment Systems Planning Study, also known as the "Producer Report" for City of Santa Ana wells potentially impacted by PFAS. In summary, this report provided preliminary details and recommendations for which wells may require PFAS treatment, an alternatives analysis for viable treatment options, a preliminary sizing and layout of treatment system equipment, and high-level cost estimates for project completion. The Producer Report included analysis of nine (9) Santa Ana wells. However, the Producer Report did not include Wells 26, 34, 35, and 37. The RFP scope of work is specific to Well 26. However, Wells 34, 35, and 37 were recently included in DDW's Executive Order DW 2022-001-DDW and must be tested for PFAS by March 31, 2023. There is no evidence currently that Wells 34, 35, and 37 contain PFAS at any level, however EEC proposes to include these soon -to -be -tested wells in the Planning Study. The EEC Team will prepare a Draft Planning Study Report which is anticipated to contain the following information: EEC Environmental 14 November 17, 2022