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S July 6, 2004 NOA Project Number: E04017A Page 4 Both percolation tests were performed on April 20, 2004 by Mr. David Welch of our office. Both tests achieved a satisfactory rate. A satisfactory percolation rate is usually considered to be less than or equal to 60 minutes per inch(drop). Table 2. Percolation Test Summary Name Elev. Test Date Depth to Soil at Percolation Test Depth(USCS) Percolation (ft) Depth Tested Ground (Rate) (ft) Water P-1 10.5 3.35 4120104 7 to 8 feet Brown-gray Silt w/f-m sand(NII.) 31 min/in P-2 2.5 1 2.15 1 4120104 0.5 feet Grayish brown to black organic silty 27 min/in clay(native)(CL.) The soil at P-1 was found to be a silty sand achieving a percolation rate of 31 minutes per inch. Other locations contained fairly clean sand and should percolate more rapidly then P-1. By visual comparison, P-1 has the most fine grained soil of all the fill soil locations and is considered the slowest of the four fill locations. Percolation test P-2 achieved a rate of 27 minutes per inch. The organic silty clay has a fairly good percolation rate. Design Calculations Falter Bed Disposal Field.- Disposal ield:Disposal of effluent is proposed in a filter bed. The Manual of Septic Tank Practice loading equation was used to calculate the absorption area required. The equation is an empirical formula which uses the percolation rate of soil to calculate the effluent loading rate. The calculation is as follows: 1. The total flow was estimated to be 4,800.gallons per day. I. The percolation rate measured ranged from 27 to 31 minutes per inch for the two soil types encountered. 3. An percolation rate of 30 minutes per inch was selected for use in the equation. The 30 minutes per inch rate should be considered conservative for the silty sand and sandy fill soils overlying the native silty clay soils for the 2nd Fairway area.