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Demolition proceeded as described in the bid, however, additional <br /> concrete materials were unearthed as excavation of borrow areas <br /> took place. These additional materials were demolished as per bid <br /> specifications. Partial backfilling of the highwalls accomplished <br /> a large degree of the pre-mining hydrologic restoration, by <br /> rounding off the steeply angled mine benches, and by establishing <br /> land forms conducive to sheet flow at borrow and fill areas. These <br /> operations were designed to minimize the concentrated drainage <br /> patterns prevalent during mining operations. Reclamation of the <br /> fan access roads was also accomplished. The outslopes of the roads <br /> were pulled into the inside of the road cut and the road angle was <br /> reversed so that the road remnant dips to the outside, thus <br /> encouraging sheet flow. Numerous rolled dips were installed on the <br /> roads in order to minimize the occurrence of long drainage paths <br /> parallel to road segments. The roads and mine benches were ripped <br /> to a depth of eighteen inches, fertilized, mulched with a blower <br /> and seeded by hand broadcasting. The mulch was disced in on <br /> flatter slopes, and crimped on steeper slopes by using a modified <br /> roller. <br /> A problem noted during previous revegetation attempts at the steep <br /> slope areas of the mine is the lack of flat spots on the slopes for <br /> seed to accumulate without being washed or blown away. An <br /> experiment was conducted during the course of the project to <br /> overcome this problem. A machine was constructed to create small <br /> benches or depressions on the outslopes for the seed to lodge. A <br /> four foot diameter roller was modified by welding six inch tall by <br /> twelve inch long steel blades perpendicular to the roller surface <br /> in a twelve inch offset pattern. This machine could be pushed up <br /> or down 2H:1V slopes by dozer, or it could by dragged up and down <br /> steeper slopes by attaching it by cable to the dozer or a crane. <br /> Trials with the machine at the partially backfilled highwalls <br /> indicated that it created the desired effect, and it was also <br /> effective in crimping mulch in these locations. Therefore, its use <br /> was authorized. <br /> Field Changes <br /> A portion of Mine 2 just west of the Mine 2 entry re-opened during <br /> the summer, creating a health and safety hazard. Field Directive <br /> No. 1 authorized the contractor to reopen the entry, and pack the <br /> mine void with dirt until refusal. <br /> Field Directive No. 2 authorized the reclamation of approximately <br /> one half mile of Road D immediately below the Mine 1 area. <br /> Reclamation of this road segment entailed pulling in the road <br /> outslope to create a 5% gradient to the outside of the roadway. <br /> Four rolled dips were constructed to accommodate drainage patterns, <br /> then the road was ripped to eighteen inches, fertilized, seeded, <br /> mulched and crimped. This was done as an alternative to the road <br /> grading conducted on Roads E, F, G, as an experiment to determine <br /> whether a steeper (5% Road D) or shallower (1% Roads E, F, G) <br /> cross sectional gradient is more conducive to the post reclamation <br /> 14 <br />