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Pond 016 Slide Remediation Plan <br />Page 4 <br />Response: The subsurface drainage coming from the western end of the Shrub Plot slide area is <br />most likely associated with the collection of subsurface drainage from the previously mined <br />areas and not subsurface runoff situated within the eastern two-thirds of this area. The depth to <br />the subsurface water level is greater than 20 feet below the existing ground surface immediately <br />upslope of the old mine ramp; therefore, installation of a cutoff channel at the eastern end of the <br />Shrub Plot slide area is not considered feasible. Channel PM-2 has been designed to collect the <br />subsurface flow at the point in which the least amount of excavation and disturbance will be <br />required. <br />9. Page 1 of the text states that the new road will be approximately 20 feet wide. Please add <br />a typical section for the road to this map, showing the proposed configuration for both cut <br />and fill situations, with roadside ditches and proposed surfacing materials and thickness. <br />Response: An approved typical section for access roads is shown in Tab 13, on page 32. SCC <br />has proposed that the road width be 20' rather than the 24' shown in the typical section. This <br />reduced road width is based on future .use and has been approved by the Division for other <br />permanent access roads at the II-W Mine. <br />10. The Division was unable to find details with the TR-73 application that describes how the <br />road will be constructed to comply with the requirements of Section 4.03.2 - Access Roads. <br />Please provide the details and required commitments, or direct the Division to the place in <br />the current permit where these items are already addressed. <br />Response: The Permit Application Package (PAP) contains sections in Tab 13, Transportation <br />Facilities (beginning on page 13) that describes and graphically portrays the design and <br />construction of haul roads, access roads and light use roads. <br />11. A vertical profile is provided beneath the plan view. The profile is drawn with both <br />horizontal and vertical scales at I "=100'. Please modify the vertical scale to be 1 "=20', <br />and add elevation levels at each VPT <br />Response: Another profile has been added to the plan view to show an exaggerated vertical <br />scale as requested. <br />12. The profile view shows only the proposed road surface. Please add an additional line <br />depicting the existing ground surface. <br />Response: We assume that pre-construction conditions (not pre-slide) are what are being <br />requested. The profile has been updated. <br />13. On the profile view, please incorporate the locations of cross-sections B, C and D; and <br />illustrate the proposed underdrains and culverts at their locations and elevations. <br />Response: The locations of all culverts, underdrains and x-sections are shown on the profiles. <br />Seneca Coal Company • P.O. Box 670 • Hayden, Colorado 81639 <br />Telephone (970) 276-5219 a FAX (970) 276-5222