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§ 1.1 and 2.1 The subject property is one mile directly north of downtown Manteca. Surrounding property use consists of agricultural production land, low density single family rural homes, ranchettes and ag buildings. Current zoning is AU20. Variance PA-2100006 was approved changing the minimum Parcel size from the AU-20 acre minimum from 20 acres to 2 acres for this Minor Subdivision. § 4.2 Any of the above land use could create environmental concerns that may be discovered in the future. As evidenced by the testing of the on-site domestic well, groundwater nitrate concentrations are elevated at 9.35 mg/L nitrate-nitrogen. The Maximum Contaminant Level is 10 mg/L nitrate-nitrogen. § 3.1, 3.2, 3.3, and 3.4 The septic system that serves the existing residential structure has been functioning properly without any problems since it was constructed in 1979. The percolation tests reveal favorable soil permeability, contributing to the lifespan of this OWTS. § 3.4, 5.4 The subject property is in an area designated as "SAND/SANDY" by EHD's map denoting the various soil types and septic system requirements throughout the County. EHD requirements in this area are leachlines or filter beds, with an equivalent of 80 feet of leachline per bedroom. § 3.5, 3.6, 5.4 A review of EHD Application Permits reveals there has been one Application for Repairs/Additions/Replacements to septic systems within the one-half mile radius study area (Appendix D). This is a low number of Permits and can be attributed to the sandy soil characteristics. § 5.0 and 6.0 SOIL PROFILE AND PERCOLATION TESTING § 5.4 The UC Davis Soil Web Map indicates the on-site soil to consist predominately of a Tinnin loamy coarse sand (#255). Typically, this soil type is well drained with limited permeability according to the Soil Web. However, a comparatively rapid permeability was confirmed by the perc test results, which as noted, is commonly observed in Manteca area soils. § 5.2, 5.3, and 5.4 A Log of Boring using the Unified Soil Classification System (USCS), as observed in each of the perc test borings, is found on the EHD PERCOLATION TEST RATE Data Sheet. Generally, the underlying surface soils show a consistent very fine sandy silt (SM), with some lean clay (CL) in the soil underlying proposed Parcels 1 and 2. Proposed Parcel 3 and 4 possess very little clay. No significant cemented silts hardpan was encountered. § 6.1 Percolation testing was conducted on each proposed Parcel illustrated on the Tentative Map found in Appendix B. Since the tests were conducted in the center of proposed Parcels 1, 2 and 3, the 100 ft radius incorporates most of the Parcel area so that a future OWTS may be installed almost anywhere on these Parcels. The perc test conducted on proposed Parcel 4 maintains a 153 ft distance from the existing domestic well. The following information describes the preparation of the percolation test boring and the actual percolation testing: Page -2- Chesney Consulting