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. the typical morainal material. Above the moraine on the left, a bench, with flatter slopes, extends 1,000 feet to the outcropping of the Red Beds. On this bench the talus cover becomes 60 feet deep just below the outcrop and is very tight. On the right a steeper slope for 500 feet to the rock outcrop is thinly covered with perme- able outwash. Exploration. Four test pits and two drill holes at loca- tion~ shown on the drawing of the dam (Drawing 254-D-146) disclosed the following conditions: Test Pit No. 1. Depth 33 ft. ~'''i' "i':&,~ "".>:"." Test Pit No.2. Depth 8 ft. Test Pit NO.3. Depth 33 ft. Test Pit No.4. Depth 25 ft. Outwash 13 feet deep, underlaid by slightly re- worked morainal material to bottom at 33 feet in the same material. A porous seam near the mar- gin between outwash and moraine seemed to account for a high rate of leakage. The pit did not reach wate~ table. A superficial cover of 3 feet of outwash contain- ing many sandstone slabs, over sandstone in place, which except for weathering is compact and tmper- vious, The pit did not reach water table. In 18 feet of outwash material, followed by 15 feet to bottom of pit, still in moraine. Appears very pervious near contact of out~~sh and moraine at 18 feet below surface. The pit did not reach water table. At 25 feet still in outwash material, which showed a very high rate of percolation, probably due to local nests of boulders. The pit did not reach water table. After about 10 feet of reworked morainal mate- rial, 92 feet of typical stream gravel and boulders mixed with weathered shale at depth. Drilled 23 feet into red sandy shale, stable and impervious. Percolation through stream gravels W3.S generally high. The unsealed casing did not give representative results for percola- tion tests in shale. Water table at river level. Drill Hole No.1. Depth 125 ft. <<) 51.