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Below is the evaluation summary for the 18444 Calla Drive Irrigation Well (APN 228-030-56) -well permit application. The evaluation, with assumptions as noted, indicates that the proposed Irrigation well is located in an area of low domestic/residential well density(1 well per section), General Plan designation General Agricultural A/G (0 —0.05 Dwelling units per acre) but is not likely to interfere significantly with existing off-site wells, create unreasonable groundwater level declines/reductions in aquifer storage or to create issues with infrastructure due to subsidence and it can be approved pending any other issues that you might have with the application. Summary: - The applicant proposes: well depth of 350 feet, a well grout seal of 200 feet with extraction rate —300 GPM with anticipated pumping schedule 144,000 Gal/day in a 24.54 acre lot. - Proposed new well is in an area of low domestic/residential (0—0.05 Dwelling units per acre)well density (31 - 35 wells per section). At least one domestic well is located approximately 550 feet West of the proposed Ag well - Based on the extraction rate of 300 GPM, The Theis drawdown chart predicts less than 5 feet of drawdown if the well is more than 100 feet away from proposed well. - Online databases do not specify any irrigation wells located within 2,000 feet of the proposed well location. Review of aerial imagery indicates an irrigation well is present approximately 2200 feet West. - Groundwater levels estimated by DWR well data range between 30 (10/9/1991)to 59 (10/26/2021)foot below ground surface over the past fifty years. Water levels fluctuate approximately 2 to 7 feet between seasonal high and low levels. - The permit application proposes a minimum well casing/grout seal of 200 feet and appears to target the Laguna - Mehrten aquifer with water-bearing zones anticipated to be under unconfined to locally confined conditions. - The annual total extracted volume is estimated to be approximately 25 million gallons, a peak pumping rate of 300 GPM, and an annualized/seasonal pumping rate of approximately 83 GPM. - The aquifer volume below the 25.54-acre parcel contains an estimated 2,043 acre-feet of water storage.The proposed extraction volume of 76.62 acre-feet per year is approximately 3.8%of the estimated aquifer storage beneath the parcel without regard to recharge each season and is considered sustainable. - The proposed well is not located within the extents of the Corcoran Clay, subsurface water- bearing sediments are semi-consolidated to consolidated, and the proposed well is not located in an area where subsidence is currently indicated,therefore subsidence is unlikely to be of significance or to create issues.