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-~- 1 1 1 1 ments of rock, frequently of a large size exceeding several feet, can be found within the soil cover. It is also known that the soils on the slope between the upper and lower benches are landslide deposits. The character of these land- slide deposits is very similar to that of the colluvial soils; landslide deposits, however, contain probably more fragments of rock than the colluvial soils. The thickness of the soil cover has not been estimated with sufficient accuracy. There are three sets of data avail- able on the thickness of the soil cover. The thicness of the landslide deposits in the vicinity of the proposed mine entries was investigated by three borings (E1 through E3), drilled under the supervision of a GEO-HYDRO engineer. The thickness of the landslide deposits at this location was estimated to range between 20 and 25 feet. The thickness of the soil overburden was estimated during ARCO's exploratory drilling. We have inspected logs of 18 borings, drilled within the area of the upper bench and above it. According to the boring logs, the thickness of the overburden ranges between 16 and 60 feet. This estimation, however, cannot be regarded as accurate as little attention is paid to the soil cover during the exploration drilling for coal. About 5 borings were drilled within the area of the upp bench by the International Engineering Company, Inc. Accordi to their boring logs, the thickness of soils varies between 34 and 50 feet. Their boring logs do not define the top of t bedrock, and the interpretation may not be accurate. Inter- national Engineering Company's drilling results were ques- ~aHrceo consuinew, iwc.