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• Mounding Analyses of the water table underlying the proposed mound system location w7existing calculated for this project since the water table is comparatively shallow at five ft belowgrade.• It has been determined that the new primary mound system disposal area can be situated north of the existing mound system. The 100%reserve/replacement/addition area will consist of the existing mound system which will become defunct and remain on standby for future use. Additional land area to the east of the existing mound also compose the total reserve area. • Although current wastewater flow volumes emanating from the completely built-out Church project are unknown,average daily flow(ADF)volumes have been formulated using all available parameters acceptable to EHD. The soils testing and investigation has found the indigenous soils under the proposed wastewater effluent disposal area to contain a predominately fine-grained clayey silty material with surprisingly rapid infiltration and percolation capabilities. Infiltration test results indicate the surface soils to possess greater infiltration capacity than what is commonly perceived in this locale. This may be attributable to surface soil cracking indicative of clay soils. Although the test results show acceptable permeability, long-term effluent acceptance rates by the indigenous clayey soils will eventually decrease in permeability. This premise is based on the number of septic system failures that have occurred and witnessed by EHD in this area of Tracy. Under EHD requirements and regulations, a mound system for effluent disposal is required in this locale and for this project due to the clayey soils,but more importantly because of the high groundwater table. A duplex pump arrangement will alternate pumping to pressure-dose effluent and distribute it equally through the new mound basal area. The mound system is described in detail on Page 12 of this Report. II. SOIL SUITABILITY STUDY FINDINGS A. SUBJECT PROPERTY AND SURROUNDING STUDY AREA INFORMATION SS As noted on the Google aerial map, surrounding land use to the north, south and west is, ha een, in agricultural production for many decades. To the east of the Church is a City of Tracy public works wastewater project. The subject property is zoned AG-40. SSS§ 3.1,3.2,3.3,3.4,3.5,3.6. Application files at EHD for repairs/replacements/additions are not available at this time for review of existing systems within a one-half mile radius study area. It is known that in the actual Larch-Clover area, there are more than 12 permits issued for repairs/replacements/additions to existing systems. This area has always had a significantly high number of repair permits due to the clayey soil and high groundwater, and may also be due to inadequately sized systems initially installed. Due to the indigenous clay soils, the proposed new system and surrounding systems will have a definite lifespan. This lifespan is indeterminable due to several known and unknown factors. 2 Chesney Consulting