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diameter angular rock riprap on the channel bottom and sideslopes. This would require development and permitting of a rock quarry to obtain material of this size and disturbance and re-reclamation of the presently stable channel. See the discussion on Windy Gulch for further justification for why the PMP event is not considered appropriate for this site. Uaoer Tailings The diversion structure around the upper tailings impoundment was also reviewed and is discussed in Attachment A. The channel will safely pass the 100 year, 24 hour event and the slope has been regraded to be a consistent one percent slope to ensure passage of this storm event. As for the lower tailings impoundment, Homestake does not believe that the PMP should be the required design storm event for this diversion structure. Portals and Mill Site Final reclamation of this area will include ripping of compacted soils to 2 feet, burying of foundations by 2 feet of cover soil, and the cut slope at the west edge of the mill area will be backfilled/regraded and revegetated to the extent practicable. Windy Gulch The native channel in Windy Gulch has been partially filled with waste rock material and the toe of the waste dump is adjacent to the original channel in some locations in the drainage. The native channel upstream and downstream of the waste rock dump has a bottom width of 3-4 feet with side slopes of approximately 1: 1. The hydrologic evaluation presented in Attachment A indicates that the constructed channel will safely pass the 100 year, 24 hour storm event as originally permitted for the Bulldog Project. The channel sidslopes across from the toe of the waste dump would require armoring with 6-9 inch mean diameter riprap where none is present. The toe of the existing waste dump currently meets or exceeds this criteria in those areas where the waste dump serves as a sideslope for the drainage channel. To pass the PMP event (3,549 CFS in the Windy Gulch drainage) the constructed channel reach would require a bottom width of 18-30 feet, depending on channel slope, and placement of approximately 60 inch diameter rock riprap on the channel bottom and sideslopes. The existing channel above and below the waste dump area does not meet these specifications. The native channels in this area could not pass the PMP event without significant erosion. The PMP design channel would also nearly exceed the constructed concrete channel in the city of Creede that handles Windy Gulch and Willow Creek flows combined. The requirement to now re-construct the diversion channels around the tailing impoundments or for a limited stretch of Windy Gulch should not be required.