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PAGE 4 • movement in the Piceance basin ..." Gas wells drilled into the naturally-fractured Divide Creek anticline and Piceance Creek dome have been faz more productive than those drilled into the same units elsewhere (Johnson, 1989, p. E30). Finally, Brooks (1986) examined the hydrologic system of the Rapid Creek drainage, producing the only information specific to the Roadside Mine area. He observed that "Most precipitation falling on bedrock becomes runoff because the rack is dense and the slopes are steep, allowing little opportunity for infiltration. This is especially true for the steep sandstone canyons formed by the Mesaverde Group." He also states that "No springs discharge from the Mesaverde Group in the sandstone canyons, indicating little ground-water movement into these canyons." He states that groririd-water flow in bedrock in general is negligible (Brooks, 1986, p. 1), and that "The minimal hydraulic conductivity of bedrock in the basin indicates that any ground-water recharge from an adjacent basin into the Rapid Creek basin,.or ground-water discharge from the Rapid Creek basin would be insignificant to the total water balance of the basin." (Brooks, 1986, p. 20). Brooks (1986, p. 23) concludes that "No critical aquifers would be dewatered by underground mining in the northwestern part of the Rapid Creek basin. Water in bedrock is the smallest part of the water balance for the basin ..." The Cameo coal zone is a relatively simple to quite complex interval, 10 to over 100 ft thick, of fresh- and brackish-water and marine rocks, primarily shaly siltstones and mudstones, with from one to over 20 coal beds varying in thickness from inches to over 20 feet (Erdmann, 1934, p. 83 and • plates 12 and 15-2 ]; personal observations). In the area of the Roadside Mine the zone generally consists of a basal silty shale between 0 and 30 ft thick, occasionally containing a coal bed up to 5 ft thick (the Cameo A, most common north of the Colorado River), and overlain by the principal coal bed in the azea, the Cameo B. The Cameo B is frequently combined with the Cameo A and lies close to or even directly on the Rollins Sandstone. This coal is fairly uniform in thickness between six and 10 ft south of the river, but quite variable to the north, from six to as much as 20 ft. Thickness variations are mostly due to splitting and split consolidation, both of which can occur over short distances. Interburden between coal beds of the Cameo interval is usually shaly mudstone and siltstone, although thin claystones and sandstones do occur. The coal contains frequent lenses and thin beds of "bone," or high-ash material; where the Cameo (A, B, or combined) lies directly on or close to the Rollins Sandstone it frequently carries grains of wind-blown sand. Published information concerning the Cameo zone is essentially limited to those sources given above, although there is more general information regarding the zone in these and other publications than regarding the underlying Rollins Sandstone. Hydrologic information is likewise limited to previously-mentioned sources, but again more data is available, although virtually none of it is site-specific to the Roadside Mine. Most of the published work concerning the interval above the Rollins Sandstone involves coal reserves and quality, and coalbed methane, gas production from the tight, lenticular, fluvial sandstones higher in the section, or both. There is virtually no published detailed information concerning this interval in the Roadside Mine -Cameo area, and elsewhere in several of the publications listed previously it is lumped together with overlying sediments in discussions of • hydrology or gas production. It is described physically in various permit applications and other government submissions prepared by or for Powderhom Coal Company and its predecessors, and Pitkin Iron Corporation and its predecessors (Pitkin Iron holds leases west of the Powderhom z