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t • • <br />2.2 Minimal Wetland Disturbance Alternative <br />Pit mining under this alternative avoids directly impacting total wetland acreage by only removing <br />strategic wetlands in specific site areas. Wetlands would be excavated from vital access areas, <br />such as the Processing Site and Phase I sector, where sufficient area is required to gain site access <br />for mining and stockpiling operations. Site mining and reclamation would be performed as <br />outlined under proposed alternative. <br />Disturbed wetlands would be mitigated (1.5: I) and reconstructed in the same manner as described <br />in proposed action section. Potential indirect impacts to wetland hydrology and function by <br />mining around the perimeter of undisturbed wetlands in site interior needs to be considered. Pit <br />mining could disrupt surface and subsurface flow adjacent to wetlands, possibly lowering ability <br />to receive water. Site observations from the monitoring wells indicate that wetland ponding <br />should not be affected by adjacent mining because accumulated fine-grained bottom sediments <br />decrease potential leakage to surrounding areas. Well monitoring commonly show that water <br />levels in the wells located in wetland fringe areas can be depressed relative to the standing water <br />in the adjacent wetlands. <br />Excavated and filled wetlands would total approximately 0,7 acre, including the 0.6 acre <br />excavated from Processing site and Phase I sector plus the 0.05 acres of fill needed for road <br />crossings. The remaining 14.1 acres of undisturbed wetlands is the product of the approximately <br />9.3 acres distributed in the various phase sectors and the 4.8 acres along the south site perimeter <br />tail water drainage ditch not mined under the proposed alternative. <br />2.3 No Action Alternative <br />Under the No Action Alternative, none of the alternatives identified here would be approved by <br />COE. The project proponent would proceed with the project by avoiding areas of COE <br />jurisdiction. Spanned bridge crossing would be constructed over Monument Creek, tail water <br />ditch, and interior wetlands in Processing Site to avoid necessary permitting for discharging fill <br />into these waters. <br />Federal regulations prohibit wetland filling but does not govern wetland excavation. Therefore, <br />site wetlands could be mined without mandated mitigation. Wetlands targeted for removal would <br />include the 9,9 acres mined under the proposed action, plus the additional 4.8 acres slated as <br />undisturbed wetlands. Total mined area would be approximately 110 acres within the 170-acre <br />site. Mining operations would proceed as described in the proposed action, but no wetland <br />mitigation would be provided. <br />2-6 <br />