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2 <br />Item 9: (Second Paragraph) Regarding runoff through the sawmill area and <br />its control to the south of the sawmill. <br />RESPONSE: Stormwater runoff and sedimentation from the cut slopes oP the <br />removal operation is currently controlled by pitching the: 5'-10' <br />immediately at the toe of the cut slope back into the bank as the <br />loader removes the material. Although this likely doesn't prevent <br />all runoff from these cut slopes from leaving the site in a large <br />storm, it has historically been successful as evidenced by little <br />obvious erosion or sedimentation South of the operation This <br />procedure together with some intermittent berming - will continue <br />through the mining operation. (See further description in the <br />following adequacy response for the Third Paragraph oP Item 9.) <br />The floor oP the operation where lumber products are stored and <br />gravel load-out occurs does slope Southerly at about 54o with <br />runoff leaving the site in roadway ditches adjacent to the ~:xisting <br />access road. Using the Rational Method fora 10 year storm event <br />it Is estimated that peak runoff currently leaving the site is 7.0 <br />CFS. This assumes 5096 oP the runoff from the cut slope is <br />intercepted at the toe with the balance leaving. <br />The reclamation plan Includes an ultimate lumber storage area of 1.6 <br />acres that will continue to route runoff Southerly to a point that <br />it leaves the site along the access drive as it does currently. The <br />permanent toe bermlditch is Intended to intercept the majority of <br />the revegetated mining slopes to limit runoff through the lumber <br />yard area after mining is complete. Again, there may tie some <br />runoff that is not captured as is currently occurring. Ina 10 year <br />storm event we have estimated 5.9 CFS will ultimately leave the site <br />assuming 50% is intercepted. <br />Runoff is currently managed without any speciPfe facilities, only the <br />removal procedures. The roadway ditches along the access road are <br />periodically maintained (graded or bladed) by the operator to permit <br />customer access to the lumber yard and this will continue as part <br />of the retail lumber business. <br />Item 9: (Third Paragraph) Regarding the use of a berm or ditch to control <br />runoff from the mining area. <br />RESPONSE: The use of a berm in the narrative and a ditch on the map was, to <br />some extent, a conflict that was not noticed when the application <br />was prepared. The intent of such a structure is to retain as much <br />oP the runoff Prom the mining area during mining as possible. This <br />would allow the water to either sink into the porous gravels or to <br />Plow across the sawmill at a rate that will limit the amount of <br />sediment leaving the site. The preference would be for ;t ditch <br />because a ditch is less likely to Pail than a berm. However, i.n some <br />locations a berm might be needed instead oP a ditch. Therefore, <br />rather than committing to just one or the other it would be <br />