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capacities, or demonstrate that post-disturbance runoff below Pond F is less or equal to pre- disturbance runoff. The response is accepted. Figures I and 2 of Volume IX were revised in the submittal dated February 11, 2004, the D-Gulch culvert will be removed. Concerning Pond F, the pond is designed to contain the entire runoff from a 10 year event so the post-disturbance runoff below pond F will be less than the pre-disturbance runoff 16. Please expand the water control measures ofproposed page 5, Volume IX, to explain the control ofsurface runoff from upstream undisturbed areas during construction of the coal mine waste bank. That is, how is upland runoff diverted from the bank while the bank is being developed. The application indicates that the coal mine waste bank is to be constructed from the bottom up, with progressive disturbance as the bank expands uphill. The response is accepted. The requested description was added to revised page 6 of Volume IX in the submittal dated February 11, 2004. 17. Please add a discussion in the permit text to describe how the pipeline section of the Deer Trail Ditch will be protected when Pond F, including the spillways, is constructed. BRL revised page 8 of Volume DC to describe the installation of a culvert in the current ditch section. Please add to the description on page 8 what diameter of culvert will be used and how deep the culvert will be buried. Also, please submit written verification that the Deer Trail Ditch Company approves of the modification. 18. How will runofffrom that section of the coal mine waste disposal site no. 2 that is next to Pond F and below ditch D-F12 be prevented from going directly into Pond F and flowing straight to the primary and emergency discharge structures, thereby short-circuiting the pond's function of providing retention time for sediment control? The Division accepts B1tL's reply. BRL responded that the gated valve on the primary dischazge pipe will normally be closed so that there will not be short circuiting. 19. On several maps and figures, a culvert is shown about 200 feet to the west of Pond F .The culvert is shown to drain to another culvert under Old State Highway 133. The inlet to the culvert appears to be very close to ditch D F-7. Please explain the function of this culvert and how disturbed area ruttoffpassing through ditch D F-7 won't drain out through this culvert, bypassing Pond F. The Division has no further concerns. BRL stated that this culvert, which is currently plugged, will be removed. Figures 1 and 2 of Volume D{ were revised in the submittal dated February 11, 2004, to omit this culvert. 20. On several maps, a large drainage area north of the proposed coal mine waste disposal site no. 2 has no topography depicted. Since the drainage areas need to be defined for several ditches, please show the topography on these maps.