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Below is the evaluation summary for the 7403 State Route 4 Irrigation Well (APN 10305013) -well <br /> permit application. <br /> The evaluation, with assumptions as noted, indicates that the proposed Irrigation well is located in an <br /> area of low domestic/residential well density(6 well per section T1N/R7E/86), General Plan designation <br /> A/G (0.0—0.05 Dwelling units per acre) but is not likely to interfere significantly with existing off-site <br /> wells, create unreasonable groundwater level declines/reductions in aquifer storage or to create issues <br /> with infrastructure due to subsidence and it can be approved pending any other issues that you might <br /> have with the application. <br /> Summary: <br /> - The applicant proposes: well depth of 600 feet, a well grout seal of 50 feet with extraction rate— <br /> 150 GPM with anticipated pumping schedule 360,000 Gal/day in a 17.7 acre lot. <br /> - Proposed new well is in an area of low domestic/residential (0.0—0.05 Dwelling units per acre) <br /> well density (6 wells per section). At least one domestic well is located approximately 1400 feet <br /> North of the proposed Ag well <br /> - Based on the extraction rate of 600 GPM, The Theis drawdown chart predicts less than 5 feet of <br /> drawdown if the well is more than 200 feet away from proposed well. <br /> - Online databases do not specify any irrigation wells located within 2,000 feet of the proposed well <br /> location. Review of aerial imagery indicates an irrigation well maybe present approximately 1,000 <br /> feet Northeast. <br /> - Groundwater levels estimated by DWR well data range between 73 (10/18/2001)to 120 <br /> (03/28//2018)foot below ground surface over the past thirty-three years. Water levels fluctuate <br /> approximately 1 to 10 feet between seasonal high and low levels. <br /> - The permit application proposes a minimum well casing/grout seal of 50 feet and appears to <br /> target the Riverbank aquifer with water-bearing zones anticipated to be under unconfined to <br /> locally confined conditions. <br /> - The annual total extracted volume is estimated to be approximately 17 million gallons, a peak <br /> pumping rate of 206 GPM, and an annualized/seasonal pumping rate of approximately 69 GPM. <br /> - The aquifer volume below the 17.7-acre parcel contains an estimated 2,323 acre-feet of water <br /> storage.The proposed extraction volume of 53.1 acre-feet per year is approximately 2.3%of the <br /> estimated aquifer storage beneath the parcel without regard to recharge each season and is <br /> considered sustainable. <br /> - The proposed well is not located within the extents of the Corcoran Clay, subsurface water- <br /> bearing sediments are semi-consolidated to consolidated, and the proposed well is not located <br /> in an area where subsidence is currently indicated,therefore subsidence is unlikely to be of <br /> significance or to create issues. <br />