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rF71nsummary, the testing and investigation has found the indigenous soils under the proposed water disposal area to contain predominately tight, hardpan, fine-to-medium sandy silty soil to a depth of five feet. Below five feet, there is a well-graded fine to medium sil Id withexcellent permeability. The percolation rates obtained from the soil testing in the pro sepo 1 location reveal the soil possesses very slow percolation at the shallow leachline depth of but rapid perc rates at the typical sump depth of nine feet. A conventional septic system arrangement is proposed for effluent disposal from this facility consisting of one septic tank to serve the house and store where customers come in, and another septic tank to serve the kennel. Effluent from the v tanks will gravity to a distribution box and leachline trenches, with sumps at the ends of the trenches. Within the text of this Report, Bolded Section (§)numbers are referenced at the beginning of an applicable Paragraph or Paragraphs, Appendix or Table of Contents that correspond with the ERD Requirements Checklist. Section Numbers referenced as SSS§, are sections applicable for the Soil Suitability Study Requirements Checklist. Section Numbers referenced as NLS§, are sections applicable for the Nitrate Loading Study Requirements Checklist. Other portions of text may also apply to other sections of the Checklists. II. SOIL SUITABILITY STUDY FINDINGS !/ A. SUBJECT PROPERTY AND SURROUNDING STUDY AREA INFORMATION SSS§ 1.1. Surrounding land use to the north, south, east and west of the project is, and has been, in agricultural production of trees and vineyards for many decades, as noted on the San Joaquin County Parcel Viewer Map. A farm labor camp is to the immediate north of the subject property,which is also on a decentralized wastewater management system. The property is zoned AG-40, Agricultural. SSS§ 3.1, 3.2,3.3, 3.4, 3.5, 3.6. Applications on microfiche file with the EHD reveal that there have been 13 permits issued for repairs/additions to existing systems within a one-half mile radius surrounding the project site. This is a surprisingly high number of permits in this specific area of San Joaquin County because the subsurface soil structure is composed mostly of a sandy silt, and the locale is sparsely developed. These repairs/additions may be due to inadequate systems that were originally installed, in addition to the tight, hardpan surface soils. The project site has level terrain; consequently, there will be no need to incorporate design considerations for slopes within the leachfield area. B. SOIL PHYSICAL CHARACTERISTICS AND ANALYTICAL TEST RESULTS The United States Department of Agriculture - Soil Conservation Service (USDA-SCS) indicates the on-site soils to consist of a Tokay fine sandy loam (#256). This soil is very well drained and has moderate permeability. However, the percolation testing demonstrated that the shallow soils at leachline depth are relatively impermeable due to tight hardpan soils, while the deeper soils at sump depth at nine feet are very permeable. This shallow impermeability is beneficial for the prevention of nitrification, as will be discussed. 2 Chesney Consulting