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1. INTRODUCTION This report present's the results of my studies and investigations of the soil and groundwater under the subject property proposed to be developed by the Applicant, Mrs. Gurdip Kelley. Mrs, Kelley is currently in the process of re-zoning the property to Freeway Services (C/FS), and is proposing to ultimately develop it into a commercial complex consisting of a Gas Station/Convenience Store, three Fast Food Restaurants,two Motels (one with a restaurant), and two Retail Strip Centers, to be constructed in two separate Phases. Physical and analytical test results from the surface and subsurface soils, and analytical testing of the underlying groundwater have yielded information on the domestic wastewater disposal system criteria for this project, with particular emphasis on nitrate loading potential emanating from the anticipated wastewater flows. The San Joaquin County Environmental Health Department(EHD) requires Soil Suitability and Nitrate Loading Studies under Community Development Title 9-1105.2 (d) for: 1.) Projects in unsewered areas, 2.) In areas currently impacted with nitrate, and/or 3.) For projects that may adversely affect the underlying groundwater with nitrate. The EHD has been at the forefront of nitrate-impact investigations and promoting the prevention or mitigation of environmental contamination from various sources of nitrate, particularly on-site wastewater disposal systems (septic systems). For a project of this magnitude, EHD requires that the two referenced studies not only investigate and analyze the project from environmental health standpoint criteria; the reports also must incorporate and discuss preliminary wastewater disposal operational parameters since they are integrally related to nitrate impact mitigation and domestic wastewater management. i A summary of the findings pertaining to the nitrate loading potential reveal soils under the proposed disposal area contain very shallow surface soils to 1.5 feet that have been regularly plowed and are therefore loose and fine-grained. These soils initially accept large volumes of water until they become saturated. Subsurface soils from 1.5 to three feet are a dense and compact, highly cemented, fine sandy silts hardpan that may be due to tillage compaction, or possibly chemical inducement. However,percolation test results show a surprising degree of permeability in this stratum. Soils below three feet are permeable down to approximately 14-15 feet, where a high clay and silt content, dense, slowly permeable soil exists, which may be beneficial for nitrate impact mitigation. i A summary of the findings pertaining to the underlying groundwater indicates that there has been f nitrate impact to the drinking water aquifers under the subject property, although not exceeding the tMaximum Contaminant Level. This maybe attributed to past agricultural production, along with natural influences under and upgradient to the property. The only Constituent of Concern found to be out of compliance was arsenic. Within the text of this Report, Bolded Section (§)numbers are referenced at the beginning of an applicable Paragraph or Paragraphs and Appendix that correspond with the EHD 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. Page -2- Chesney Consulting