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INTRODUCTION This report issues my findings regarding the Nitrate Loading Study (NLS) conducted for the referenced project. A Soil Suitability Study for this project was completed by the engineering firm CTE Cal, Inc. and is submitted concurrently with this NLS. These Studies were required because of regulations enacted by the San Joaquin County Environmental Health Department (EHD) to ensure nitrate loading standards are adequately assessed when new improvements occur on a subject Parcel. Specifically, concerns regarding nitrate loading could potentially occur when additional residential unit dwellings are constructed on comparatively small parcels. This project is a proposed third unit dwelling on the subject Parcel, composed of 5.72 acres. Within the text of this Report, Bolded Section (§) numbers are referenced at the beginning of an applicable Paragraph(s), or Appendix that corresponds with the EHD Nitrate Loading Study Requirements Checklist. Other portions of text may also apply to other sections of the Checklist. The following summarizes the investigative parameters included to complete this report: • Soil chemical testing was conducted on soil samples retrieved from a backhoe test pit in the proposed location of the new leachfield area. Physical testing of the soil sample included texture particle size analysis for sand, silt and clay content, and chemical testing analyses for the constituents that influence nitrate loading. • The nitrate loading to the on-site soils in combination with nitrate impact potential to the underlying groundwater from percolating effluent was quantified through generally accepted calculations. An assessment of the characteristics of the on-site soils was made to discuss the mitigation of nitrate impact. • A well water sample was retrieved from the existing on-site domestic well for analysis of nitrate, the agrichemical DBCP, and alkalinity. SOIL INFORMATION NLS§ 1.1. The UC Davis Soil Map indicates the Map Unit Name soil type is 85% Tinnin loamy coarse sand (#255), with the remaining percentages as Delhi, Manteca, Veritas, Honcut and Timor loamy sands. The retrieved soil samples referenced in the attached texture analysis reveals the on- site soils at the 3 ft and 6 ft depths consist of loamy sand and at 9 ft the soil is a sand. The sand, silt and clay percentages are illustrated on the Test Report. NLS§ 1.2. The soil samples retrieved were also tested for chemical analysis. As noted, the chemical analyses conducted quantifies several constituents that influence nitrate loading for this project. The important parameters for nitrate loading assessment are the organic matter, clay content, pH, cation exchange capacity (CEC), and the nitrate -nitrogen content of the soil. Page -1- Chesney Consulting