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After the road was constructed, topsoil was placed in a thin veneer on the • face of cutslopes to serve as a rooting medium for establishing vegetation and were hydromulched and seeded in 1977, with seed augmentation occurring in 1978. Several slopes, especially those facing east, exhibited evidence of surficial slumps or downhill creep; and, upon examination, these features occurred along the topsoil/cutslope interface and were not considered evidence of deep-seated instability (Ertec, 1981 - report on file with CMLRD). On April 26, 1980, a landslide occurred in an area adjacent to a gas pipe- line (referred to as the Gas Line Slide) (Map 8). CMLRD requested Sun Coal Company to conduct a study (Ertec, 1982 and 1983) to evaluate the cause of the landslide and, if necessary, recommend and adopt appropriate measures to main- tain road corridor stability. During the sunnier of 1981, extensive surveys were conducted to obtain haul road information. A controlled areal survey was con- • ducted to provide information related to shop facilities, road grades, culvert, runout, ditch, and sediment trap locations. Map 8, with a two-foot contour interval at a 1 inch equals 100 feet, was generated to provide an adequate base to conduct geotechnical, geological, and hydrogeological studies. According to a study conducted by Ertec in 1982-1983, the gas line slide area appeared to be a rotational type slope failure caused by many factors -- factors related to natural conditions, the landowner's oil drilling and grading activities, and gas pipeline and mining construction and maintenance activities. Sun Coal Company, in an effort to stabilize the slide area, routed water from the rotational slip head scarp, installed larger inside road cut ditches, and graded and reclaimed the slide area. . In addition to identifying this area, three other areas exhibited potential stability concerns. These areas are identified on Map 8 and are located above - 172 - (Rev. 5/86)