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Cross Gold Mine <br />December 2024 D-7 <br /> <br /> <br />Facility Square Feet Acres Approximate Dimensions <br />Septic Tank and Leach Field 3770 0.0865 N/A <br />Munitions Bunker (North) 56 0.0013 7x8 <br />Munitions Bunker (South) 56 0.0013 7x8 <br />Diversion Channels 121168 2.78 N/A <br />TOTAL DISTURBED AREA 380,976.0 9.33 N/A <br /> <br /> <br />As outlined in the Boulder County Development Agreement (dated August 22, 2011), Grand Island <br />Resources (GIR) plans to construct an internal property road connecting the Cross Gold Mine to the <br />Consolidated Caribou Mine. Referred to as the “Cross Caribou Access Road” (shown on the Exhibit C <br />maps), this route uses Boulder County’s non-paved road guidelines as a basis for key design parameters. <br />The proposed road alignment is approximately 1,000 feet in length, starting at about 9,688 feet in <br />elevation at its southern end and concluding near 9,740 feet at its northern terminus. The roadway <br />centerline is aligned to take advantage of natural topographic features, manage surface and subsurface <br />water effectively, and reduce erosion. By following the existing contours, the design seeks to minimize <br />disruption to natural drainage patterns. <br />For design purposes, cut slopes are generally assumed at a ratio of 1.5H:1V. In areas of competent rock, <br />slopes may be as steep as 0.5H:1V, while sections of weathered rock may require 1H:1V slopes. Fill <br />slopes will be constructed at a minimum of 1.7H:1V. To accommodate Coon Track Creek, the road design <br />incorporates twin 5-foot by 4-foot pre-cast concrete box culverts sized to handle a 100-year peak flow <br />event. Energy dissipation structures will be constructed both upstream and downstream of the culverts <br />to further control erosion and maintain the stability of the waterway. <br />Cross Caribou Access Road Design Parameters <br />Minimum Radius Horizonal Curve: 45 ft Maximum Gradient: 8% Max <br />Minimum Length of Vertical Curve (Sag): 80 ft Minimum Length of Vertical Curve (Crest): 80 ft <br />Road Width: 20 ft Min Fill Slopes: 2H:1V <br />Side Slopes (Cut): N/A Surfacing Thickness: 24” <br />6. Refuse, Acid, or Toxic Producing Materials <br /> <br />Given the nature of the host rock and ore body, acid rock drainage (ARD) should not occur. (Prior <br />analyses submitted and reviewed by the DRMS have shown the host rock and ore body to be non-acid <br />producing.) Baseline water sampling over the last twenty years confirms these conclusions with