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Colorado Mined Land Reclamation Board <br /> Page 6 <br /> March 2, 2018 <br /> perimeter is entirely sealed,the perimeter drain will serve to route groundwater around the lined pit by <br /> maintaining a high permeability area adjacent to the compacted backfill. <br /> The Division finds the Applicant has supplied the information required by Rule 6.4.7 and the operation <br /> will minimize disturbances to the prevailing hydrologic balance of the affected land and surrounding <br /> areas both during and after mining with respect to existing groundwater levels. <br /> c. Concerns regarding the impact of groundwater drawdown on adjacent trees (4) <br /> The proposed mine site is not located within a riparian area and the Division finds it unlikely the adjacent <br /> ornamental vegetation would be reliant on groundwater and would likely rely more on surface irrigation. <br /> Given the temporary nature of the drawdown at the site and LRM's proposed plan to mitigate the impacts <br /> to adjacent well owners to insure use of their wells for irrigation continues,the Division finds the <br /> operation will not adversely affect the surrounding vegetation. <br /> d. Concerns regarding the effectiveness of the proposed perimeter drain. (12) <br /> LRM has provided a demonstration the perimeter drain has been designed to adequately move <br /> groundwater around the perimeter of the lined pits. LRM has also provided a groundwater level <br /> monitoring plan that will allow both LRM and the Division to evaluate the effectiveness of the drain both <br /> during mining and reclamation. <br /> e. Concerns regarding flooding,flood management and mapping. (2) <br /> The Division has reviewed the proposed site's location in relation to the Federal Emergency Management <br /> Agency(FEMA) Floodplain maps provided by the City of Fort Collins. The Knox Pit permit boundary is <br /> located outside of the FEMA High Risk Floodway, High Risk 100 year Floodplain and the Moderate Risk <br /> 1001500 year Floodplain(please see the map below). Regarding surface water management, LRM has <br /> designed the site to direct surface flow into the pit basins and designated stormwater sumps. <br />