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-11- During reclamation, the Crown Ditch will be maintained and kept operative. Therefore run-off from the area upstream of the Crown Ditch will be diverted away, and will not affect, the reclaimed drainages. When the area is reclaimed (stabilized), the Ditch will be breached. At that time the curve number representative of the entire area should again be 60. Comparison of run-off charts for CPl 60 and CN 72 indicates that the flows along the drainages in the disturbed area should be about the same in the early stages of reclamation as they will be after reclamation when the diversion is breached. Item: With regard to the cascade drop structure, the amendment should address ho'w durable and competent the rock slope is in this area and whether it would be appropriate to include an energy dissipator at the base of the structure. Response: As discussed on page 11 of the Supplemental Report 5-1, if competent bedrock cannot be found, a design to accommodate the lack of competence would be adopted. Reconnaissance analysis of the likely site indicates that competent bedrock may exist. In view of the continuing need to design the cascade structure based on additional site analysis, Homestake hds included a line item in the surety calculations of Exhibit L, under the heading "Engineering Investigations and Design," of $10,000 for the designing of the cascade structure. The cascade structure will incorporate energy dissipating features in order to achieve its purpose. Item: How is drainage to be handled along the areas that are to be reclaimed in the North Pit and how will the drainage be affected by earth movement (settlement)? Response: Homestake plans to perform the necessary grading ("dressing") after the landslide has reached its equilibrium (stable) configuration. The design of the drainages will conform to the objective of allowing limited amounts of water to drain down protected faces of the fill. Water bars can be incorporated into the design should they be necessary to control erosion. At the shallow grades involved, such structures may not be necessary. Homestake agrees that since these designs will evolve as site-specific data and are collected during the initial phases of reclamation, adequate surety should be included. Therefore an item for final design for grading and drainage of the disturbed area has been included in Exhibit L under the section titled "Engineering Investigation and Designs." Item: Is the intersection between the South Pit drainage and the drainage above the Tie Camp dump to be armored? Response: As in the case of responses to the two previous items, Homestake plans to develop site specific construction designs that will have as their objective protection of the drainage. The design will take into account the potential for excessive erosion at the intersection noted and additional armoring will be used if necessary. All drainage junctions will be so evaluated. As stated above in response to other items, surety for final design for drainage of the disturbed area has been included in Exhibit L under the section titled "Engineering Investigation and Design."