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Bayfield Pit t11 Adequacy Letter Response Page 5 ^ Mining will occur east of the batch plant in the area described as Phase II. Water will be pumped into Phase III during the mining of Phase II. Phase II will be reclaimed as a reservoir. Exhibit D con[.: You state that during operation, mining will occur in and azound previously mined azeas, though no reference is made to a specific location. Is there pre-existing mining disturbance in the 10.3-acre area? Mining has occurred in portions of Phase I and III. The amendment proposes to continue mining these areas and the new amendment area of Phase II. Exhibit D cont.: This exhibit requires information about points of access to the new azeas, types of disturbance within each affected area, methods of salvaging and protecting topsoil, stockpile locations for topsoil, overburden and product, direction of mining, description of phases, depth of mining, type of stratum below the material to be mine, slope gradients during mining, azeas of waste material fill, number of acres to be affected at any one time, etc. The azea to be mined is approximately two miles south of the Town of Bayfield and lies on the alluvial plains above the Los Pinos River at an elevation of approximately 6,750 feet. The site affected is an existing gravel pit that has been mined intermittently since about the 1940's. Historically, the site was mined relatively shallow, averaging about five to seven feet in depth, and encountered groundwater. The anticipated direction of mining and location of stockpiles is portrayed on the mining map. Phase I will work primarily in the existing pit, with mining expansion occurring to the east. Phase I will be mined to a depth of ] 9 feet. Phase II has not been mined in the past. This area will be mined from north to south at a depth of 25 feet. Phase III has been mined in the past to a depth of 12 feet. This area will may be expanded to a depth of 19 feet. During Phase III mining will transpire along the northern boundary of [he lake in Phase III and the southern azea of the lake in Phase I. This area will be mined and then diked to separate the lakes in Phase I and Phase III. Topsoil will be stockpiled in the denoted azeas on the map. As a stabilization measure, any topsoil which is to remain in a stockpile longer than one growing season will be broadcast seeded with a perennial sod-forming grass cover such as Western Wheatgrass at a rate of 20 pounds per acre. Mining will approximately occur at a depth of 6,748 feet in Phase I, at 6,744 feet in Phase II and 6,734 feet in Phase III. All final slopes of the reservoirs will be graded to no steeper than 2:1, except from 5 feet above to 10 feet below the expected water line where slopes shall not be steeper than 3:1. Exhibit D cont.: In following the approved mining plan, the pond slopes would range from 2:1 to 3:1 depending on their location relative to the water level. The map in Exhibit C shows only 3: I slopes. Are there to be only 3:1 slopes azound the ponds during mining? Do all sloped areas which will not be redistribute in the future have only 3:1 slope gradients on them now?