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' maintaining natural drainage patterns. Therefore, with mitigation, existing uses, including vehicle
<br />traffic, blasting, and heavy equipment placement, would result in localized, long term, negligible
<br />to minor, adverse impacts on geology and soils within the analysis area.
<br />At the conclusion of mining, a reclamation plan would be followed to rehabilitate the disturbed
<br />area. This plan would include stockpiling of topsoil to redistribute over the disturbed areas,
<br />seeding of topsoil for 2 consecutive years, and monitoring and controlling noxious weeds.
<br />Reestablishment of vegetation would reduce the loss of soil through wind and water erosion.
<br />Cumulative Impacts
<br />Under Alternative A, No Action, cumulative impacts on geology and soil throughout the park
<br />could result from continued visitor use in the area and on the BLM and CDOW lands, which
<br />could continue to compact soil or cause increased erosion and soil foss. Vehicle traffic on
<br />unimproved roads would contribute to soil compaction in the area. Other mineral mining
<br />operations in the area would remove soil and geologic material. Leaks and spills from vehicles
<br />along US 50 and on dirt roads on BLM and CDOW lands could result in localized, minor impacts
<br />on geology and soil. Cumulative impacts on geology and soils throughout the park are
<br />expected to be localized near developments, with short to long term, negligible to minor,
<br />adverse impacts.
<br />L Conclusion
<br />Under Alternative A, No Action, the Dickerson Pit would not expand. Current operations at the
<br />pit such as blasting, heavy equipment operation, vehicle traffic, and the possibility of leaks or
<br />spills of hydrocarbon products used on-site, would result in localized, long term, negligible to
<br />minor, adverse impacts on geology and soils within the analysis area. Cumulative impacts from
<br />existing mineral development operations in the area, BLM and CDOW owned roads, and visitor
<br />uses are expected to result in short to long term, negligible to minor adverse impacts, localized
<br />near developments throughout the park. No impairment to geology and soils would result from
<br />implementation of this alternative.
<br />Impacts of Alternative B, Proposed Action, on Geology and Soils
<br />Under Alternative B, Proposed Action, the Dickerson Pit would expand to its full mineral right of
<br />' 33.16 acres, minus the 1.22 acres reserved as a visual buffer. Impacts on geology and soil
<br />within the analysis area would be greater than Alternative A, No Action, with localized, long
<br />term, moderate, adverse impacts associated with vehicle use, heavy equipment placement
<br />' blasting, reclamation grading, the possibility of leaks or spills of hydrocarbon products used on
<br />site, and potential long term loss of soil productivity due to steepened slopes following
<br />reclamation.
<br />Mitigation measures to protect soil would include those under Alternative A, plus the
<br />construction of additional sediment control basins as the floor of the pit enlarges. These
<br />measures would be designed to limit erosion during the period of mining activity. Following the
<br />completion of mining activities, the site would be reclaimed to limit erosion. The site would be
<br />graded to a 2:1 slope, with occasional changes in slope to mirror the natural surroundings, the
<br />floor area would be scarified and covered as necessary where it would improve the surface for
<br />vegetation growth, and the site would be monitored for 2 years by the Colorado Division of
<br />Minerals and Geology and NPS. All other reclamation outlined for Alternative A would also
<br />apply to Alternative B. The potential for leaks and spills exists during all phases of mineral
<br />development operations, resulting in impacts that could have severe, but localized effects on
<br />geology and soils; however, with the mitigation measures included with this alternative, the
<br />intensity of impacts would be reduced. With mitigation, the Dickerson Pit expansion would
<br />result in localized, long term, moderate adverse impacts on geology and soil.
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