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G. FF2. SOILITABILITY STUDY FINDINGS AND SITE EVALUATIONSing the project is one of the most important elements investigated for this report.nt of wastewater effluent by the soil primarily protects human health and mitigatesegradation. Water flow through the property soils, by gravity(downward),y, d by capillary action and evaporation(upward),were studied for this project. The findings presented below have determined that at different elevations,the property soils possess characteristics that are simultaneously favorable and restrictive for the management of wastewater effluent. Surface and Subsurface Soil Characteristics Topography of the soil surface shows the land declination to be in a northerly direction. The southern boundary is at an elevation 118 feet MSL, while the northern boundary at Valpico Road is approximately 107 feet MSL. The southern border of the proposed wastewater disposal area is 110.5 feet MSL and declines to approximately 107 feet MSL, over a distance of 350 feet. Consequently, the slope is -1%. This is an acceptable surface slope for the disposal area and may be maintained during construction. The drip irrigated disposal area; however,must not be mounded and should be level in surface elevation. As evidenced in the attached Photographic Plate C,the surface soils consist of recently plowed soil aggregates (clods)to a depth of six to ten inches. Below this disked soil is a densely compact soil structure with significant soil cracking. Having hand-drilled in several locations, a considerably dense"plow layer"is quite evident from 12 inches down to approximately 24 inches in depth. This severe soil compaction was probably caused by tractor wheel compaction under optimum soil moisture conditions during tillage. Under this layer at approximately three feet, the soil density is significantly less dense and composed of a yellowish brown, fine silty sand material, with excellent permeability. To investigate subsurface soil conditions and characteristics, four backhoe test pits were excavated directly east of the proposed disposal area under ASTM Standard Practice for Subsurface Site Characterization of Test Pits for On-Site Septic Systems. Photographic Plate B clearly illustrates the surface and subsurface soil characteristics of soil Horizons O (organic), A, B and C. As referenced above, Horizon C is approximately three feet below a plow layer, consisting of the yellowish brown, silty sand material. i Soil Physical Test Results The National Resources Conservation Service (NRCS) - Soil Conservation Service indicates the soil in the proposed disposal area to be partly in Zacharius Clay Loam (#281) and predominately in a Stomar clay loam (#252). The Zacharius soil has been denoted has having moderately slow permeability with an average available water holding capacity of 0.15 to 0.19 inch/inch for the top five feet of soil, for a total of 9 to 11.4 inches of water. Stomar soil also has slow permeability, with an average available water holding capacity of 0.16 to 0.18 inch/inch throughout the top five feet of soil (9.6 to 10.8 total inches of water). Over the proposed disposal area of approximately 39,000 W, the top five feet of soil can theoretically hold: 0.90 acres x 27,154 gals/ac-in x -11 inches=268,825 gallons of water. Page -4- Chesney Consulting