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Mr. Marcus Middleton - 4 - January Z4, 1991 Demonstration Areas As we have previously discussed, the Division can approve a proper demonstration for certain areas of Mine No. 3, pursuant to Rule 4.05.2(2). This is done very rarely; therefore, we must ensure that all components of the demonstration are complete, and will withstand reasonable scrutiny. The following additional information must be submitted. 1. / Provide a demonstration for all areas, which shows that the "quality of untreated drainage from the disturbed area meets State and Federal water quality standard requirements applicable after the sedimentation ponds and treatment facilities are removed, if any, for receiving streams." This demonstration will rely on historic water quality monitoring data. 2.~ Your proposal to use an erosion index, plus the USLE is an acceptable method to show that the areas are not contributing "additional suspended solids above natural conditions". Please clearly explain, however, your reasons for not attempting actual water quality sampling to make this demonstration. 3. /Submit any actual sediment concentration data which were collected to substantiate the proposed demonstrations. The Middle Creek data, referenced in your submittal, must be submitted. 4. Please note that the water quality of pond discharges, specifically sediment concentration data, is not significant in that the pond settles sediment, and the discharges are not representative of uncontrolled flows. Do you have any data for pond infl ows? 5. ,/ Please provide a letter from your local Soil Conservation Service Agent which provides the following information: a. Agreement that the submitted USLE calculations have been properly applied to the Mine No. 3 area, b. Verification that the K factor of .32 is proper. Actual published soil survey information should be included with this verification. c. Verification that the projected soil losses are acceptable according to Soil Conservation Service criteria for the area. 6. /Supply all of the information used to derive the erosion index. Include the reference for the technique maps which show the locations of the parcels listed in your submittal, and the actual tabulated field observations. 7.~ Submit the actual vegetation data referenced for each "Demonstration Area" and for the "Reference Areas". 8. /Specifically show, on a map, each Reference Area used for comparison. Your analysis should a]so show the calculated sediment loss values for each reference area, without holding any variable constant. Comparisons such as the ones provided are good, and should be retained. The analysis will be strengthened, however, by using actual reference areas, for both Mine 3 North and Mine 3 South, using actual conditions for variable derivation.