1977-05-19 Septic System Design Report

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77-159 Nitz, Inc. -3- May 19, 1977 Surface Soil At Rate Test # Elevation Test Depth m i P-1 95.0 Sandy Clay (CL) 120 P-2 92.8 Sandy Clay (CL) 48 P-3 93.5 Sandy Clay (CL) 120 P-4 90.0 Sandy Clay (CL) 120 P-5 87.3 Sandy Cldy (CL) 35 P-6 86.0 Sandy Clay (CL) 34 The average of these 6 initial percolation tests are then 80 mpi. As indicated to you in a telephone conversation, percolation tests P-2, P-5 and P-6 met the percolation requirements while tests P-1, P-3 and P-4 indicated values outside the limits for a typical individual sanitary sewer system. At that time, in our opinion, it appeared likely that a suitable drainfield site can be located in the lower area somewhat to the south of the present proposed location as indicated by tests P-5 and P-6 and on the boring where suitable granular soils were encountered at or near elevation 83±. At your request, on May 17 two additional percolation tests (P-7 and P-8) were performed, approximately 30 feet further south than the location of P-5 and P-6 and both were conducted at or near elevation 81± per the assumed datum. Readings were taken on these two additional percolation tests on May 18 with the following results: Soil At Soil At Rate Test !# Test Depth Test Depth m i P-7 81± Slightly Silty Sand (SP-SM) 10 P-8 81± Slightly Silty Sand (SP-SM) 10 REMARKS: In our opinion, a suitable drainfield can be situated imme- diately to the south of the proposed location with the start of the drainfield at or near the location of percolation tests P-5 and P-6 and running parallel to the downslope contours to the southeast of the proposed house location. Of necessity, the area of the power auger boring and perco- lation tests in relation to the area of the proposed drain - field and the depth of the boring are limited. Suggestions and/or recommendations of this report are opinions based on the data obtained from the boring and the tests. BRAun' ENGINEERING TESTING