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and 3.)Discuss operational parameters to achieve the two goals of proper wastewater management and nitrate loading mitigation from the mound disposal system. This was accomplished by the referenced testing,physical/chemical analyses and operational parameters incorporated into the design of the wastewater disposal system. • Conduct soil physical and chemical testing to determine the following: Physical testing included percolation testing and particle size analysis of the soil characteristics underlying the effluent disposal area. Chemical testing included analyses for the constituents that influence nitrate loading. • Mounding Analyses of the water table underlying the proposed mound system location has been calculated for this project. • Groundwater depth was measured in the sounding of the aforementioned domestic well and found to be four feet below the top of the well casing. Since there was no electricity to this well, chemical analysis to assess and quantify nitrate loading potential to the underlying groundwater could not be ascertained. • From the Site Plan prepared by the firm of Shack and Company, it has been determined that the primary disposal area and the required 100%reserve/replacement/addition area can be easily situated in the northeast comer of the subject property. • Although ultimate wastewater flow volumes emanating from the completed project are unknown, the average daily flow(ADF)volume was formulated using all available parameters acceptable to EHD. Average daily flow volumes of domestic sewage are expected to be comparatively small. However, since there will be a kitchen/conference building, the wastewater is anticipated to have a comparatively higher strength. • Per the request of EHD,correspondence between the Applicant and the City of Tracy regarding information on the domestic water supply,has been included in this Report. In summary, the soils testing and investigation has found the indigenous soils under the proposed domestic wastewater disposal area to contain a predominately fine-grained clayey silty material with surprising infiltration and percolation capabilities. Infiltration test results indicate the surface soils to possess greater infiltration capacity than what is commonly perceived to be in this locale. The observed subsurface permeability at the tested depths may be due to an encountered gravelly- clayey stratum found between 24 inches and 40 inches below the existing ground surface. Although these test results show acceptable permeability, effluent long-term acceptance rates by the indigenous soils can be assumed to decrease substantially. This premise is based on the number of septic system failures that have occurred, and witnessed by EHD in the Larch-Clover area of Tracy. Under EHD requirements and regulations, a mound system for effluent disposal is required in this locale due to the clayey soils and high groundwater table. A duplex pump arrangement will alternate pumping to pressure-dose effluent and distribute it equally through the mound basal area. The mound system is described in detail on Pages 15, 17 and 18 of this Report. 2 Chesney Consulting