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the 9.5 ft diameter of the culvert will pass the 10-year, <br />24-hour storm event of 838 cfs but not the 20-year, 24-hour <br />event of 1675 cfs. The culvert is sized for 1149 cfs, <br />therefore being 526 cfs under designed. Prior to the spring <br />runoff in 1985, the operator designed and installed a dip <br />section over the existing culvert. This dip section will <br />safely pass the additional requirement of 526 cfs. For more <br />information regarding the creek crossing see Section 2.5.3(4) <br />and Appendix C in the permit application. <br />4. The creek crossing will be reclaimed once Pond No. 5 is no <br />longer necessary and removed. <br />B. Access Roads <br />The Blue Ribbon Mine site has no access roads; therefore, <br />this section does not apply. <br />C. Light-Use Roads <br />The Blue Ribbon mine has one light-use road on site, which <br />intersects the haul road on the east side of Hubbard Creek <br />beneath the mine bench. The road was used to perform <br />maintenance on Ponds No. 1 and No. 2, and to provide access <br />to other facilities. The road now allows for maintenance on <br />Pond No. 5 and access to the Mine bench. <br />2. The light-use road will be reclaimed once Pond No. 5 is no <br />longer necessary and removed. <br />II. Support Facilities - Rule 4.04 <br />A. All facilities used in support of mining activities at the Blue <br />Ribbon Mine, have been removed. Construction of support facilities <br />did not result in any damage to any protected structures within the <br />permit area. Therefore, the Division proposes to approve those <br />activities (4.04(6)). <br />III. Hvdroloaic Balance - Rule 4.05 <br />A. Water Quality Standards and Effluent Limitations <br />There are currently three sediment ponds at the Blue Ribbon <br />Mine that treat drainage from the disturbed area. These <br />ponds function as designed to ensure that applicable water <br />quality standards and effluent standards are met. <br />B. Diversions and Conveyance of Overland Flow <br />Sediment control ditches have been designed and constructed <br />in compliance with Rule 4.05.3. Locations are shown in <br />Exhibit H-1 and Exhibit Z. Designs are detailed in Appendix <br />L of the permit applications. <br />-15- <br />