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In an effort to intercept the seep source, a test pit was dug on <br /> the facilities area bench. The Colorado Geological Survey (CGS) <br /> provided an individual to supervise the project and obtain samples. <br /> This pit was excavated by a large track mounted backhoe to a depth <br /> of about 27 feet. Due to unstable ground conditions, the hoe could <br /> not excavate further. It is estimated that the elevation of the <br /> seeps were about five feet lower than the base of the pit. Soil <br /> samples were obtained, however there was no visible evidence of <br /> hydrocarbons in the material excavated from this pit. <br /> A second pit was excavated immediately north of the "Eimco Shop" <br /> near the main entry gate. This is a location which reportedly <br /> contained an underground diesel fuel storage tank. Evidence of <br /> hydrocarbon contamination was apparent almost immediately, in that <br /> soil excavated from this area smelled of diesel. No pools of fuel <br /> were observed. Samples of this material were obtained by the CGS <br /> representative. It is assumed, based upon observation, that this <br /> area is not the source area for the seep, nor is it presumed that <br /> this area is a significant problem. However, definitive <br /> conclusions cannot be reached until the soil analyses and report <br /> are received from the Colorado Geological Survey. <br /> A number of revegetation experiments were conducted at the 4 Mine <br /> outslopes this year. One erosion control experiment was also <br /> started at this location. <br /> The reclamation bids for the 3 and 4 Mines included hydro seeding <br /> of the mine bench outslopes. These slopes appear to approach and <br /> exceed 1H:1V in areas. They are generally heavily rilled and <br /> gullied, with a moderate surficial crust which develops on the <br /> material. The outslopes are composed of material excavated to <br /> create the highwall, and of trommel reject. A fair amount of <br /> larger rock is present, and protrudes through the finer materials <br /> along the outslopes. The hydro seeding covered the outslopes <br /> relatively evenly for a distance of about 250 feet below the bench <br /> crest. This was as far as the hydro seeding machinery could throw <br /> the slurry. <br /> Four revegetation test plots were established on the south east <br /> facing outslope of the Mine 4 access road immediately south of the <br /> mine bench. This area is comprised of a slope which appears to be <br /> fairly representative of many outslopes observed throughout the <br /> mine site: slopes approach and even exceed 1H:1V, they are composed <br /> of material down cast from road and/or mine bench construction, the <br /> material is composed of sandstone, carbonaceous shale and coal <br /> production by-product, the slope currently supports sparse <br /> vegetation, the slope exhibits many erosional features such as <br /> rills and gullies. <br /> The four test plots are, from north to south, (1) hydro seed and <br /> hydro mulch, (2) hydro seed and hydro mulch applied over artificial <br /> benches constructed on the outslope, (3) Soil Guard applied over <br /> 14 <br />