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M-97-084/2nd Adequacy 10/30/97 page 2 precipitation event could result in a runoff volume of over 200,000 gallons (plus debris). Please comment if this seems incorrect. My concern mainly involves post-mining channeling of the runoff and containment of debris (the highway is less than 200 feet from the mouth of the chute). Will this be something that the approval of the City permit may require? I will mention the channel and containment, plus potential damage to the highway, again below. Exhibit C -Mining Plan Your plan to expand the permit area to allow mining of the unconsolidated material in the chute is good, and the plan to mine from the top downward is satisfactory. Please note, however, that this activity, and others too, will begin to affect land which is vegetated. Preparing the site for mining and leveling must include more than simply removing the trees. You must salvage topsoil, since it maybe needed for final reclamation. Topsoil stripping must be performed on the access road and stockpile/processing area prior to placement of any fill materials or traffic impacts. (This is stressed because the existing flat area and road, being on the bottomland, surely still are covered by topsoil, and your possible need for soil does not allow the luxury of wasting it.) Additionally, since the area where the alluvium is to be mined has no topsoil, but will eventually be level and, at that point, be subject to the same reclamation needs, an adequate volume of fine material must be salvaged during screening, to be used for growth medium in final reclamation. I will explain this more below. The south edge of the permit abuts a level pasture which is a couple feet lower in grade titan the land on the permit area. Normal mining activities may make material rolling onto the pasture a strong potential problem. Please describe how it will be mitigated. Exhibit D -Reclamation Plan As I mentioned in my first adequacy letter, reclamation must be perceived as a task to be performed either when the site is partially mined or when it is fully mined, for purposes of determining the bond amount. When the site is partially mined, I concur that the remaining undisturbed slopes on the alluvium maybe left at their undisturbed gradient, as long as drainage control is assured and vegetation removal has not left an unstable site (the woody vegetation contributes to stability of the surface). All alluvial material that has been moved will have to be graded to a stable configuration, which you have stated will be no steeper than 3:1 in the chute. feel that 3:1 should be the maximum reclaimed slope for any disturbed area of the permit. Please comment. You have described the removal of woody vegetation, which I understand will be ongoing. There should be, therefore, no stockpiles of woody material to be disposed of during the operation (whose removal would require a portion of the bond money to pay for). The reclamation of the level areas may ultimately be toward a commercial post-mining land use.