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parameter, rather than a water quality criteria parameter. <br />A.4. Ditches and berms associated with the SAES have been drafted <br />onto Maps 10 and 11. <br />A.5. Basin Resources has utilized an optical estimate of vegetative <br />cover to predict CP values. <br />B.1. SAE #1 is the Return Air Shaft bench located west of the Pond <br />002 cells. It has been identified on Map l0. <br />B.2. SAE #1 is a very small fan pad with a substation, a fan and a <br />building surrounded by a well vegetated area and a narrow <br />gravelled access. Assuming that only half the site is <br />vegetated to 25% weeds and 60% cover (CP value of 0.038), and <br />the structures and the gravelled pad have 60% gravel cover, <br />(CP value of 0.18) a merged CP value of 0.109 can be used to <br />achieve a projected total settleable solids value of 0.36 <br />ml/1, less than the effluent standard of 0.5 ml/1. <br />C.1. The CP table in SEDCAD+ contains CP values for gravel in terms <br />of percent cover. Basin is committing to various gravel <br />cover requirements (i.e. 20% or 60%) as needed to achieve the <br />effluent standard. In practical terms, 100% cover would <br />consist of 2 inches of clean gravel. <br />C.2. Basin interprets the need to document straw bales differently <br />than the Division. Rule 2.05.3(4) indicates that designed <br />structures need to be documented within the permit <br />application. The Division allows the use of straw bales as <br />"structures" to achieve effluent limitations on small area <br />exemptions. If Basin was using straw bales as the main <br />structure to achieve effluent limitations, the mapping of <br />these would be appropriate. However, the demonstration for <br />SAE #8 predicts that a gravelled pad is adequate to maintain <br />effluent limitations. Rule 4.05.5(2)(f) indicates that straw <br />dikes are a tool which can be used to control sediment at a <br />mine site. Basin respectfully requests the right to utilize <br />a redundant system such as a straw bale or silt fence to <br />prevent additional contributions of sediment to streamflow or <br />runoff outside the permit area at any location on their <br />property without documenting such use on maps. <br />D.1. SAE # 9 may be found on Map 10. <br />D.2. Please see the response to C1. <br />D.3. A revised run for SAE #9 has been provided which includes a <br />separate subwatershed for the topsoil pile and a Time of <br />Concentration value reflecting 30 percent slopes on the pile. <br />D.4. The ditch run for the southern clean water diversion ditch is <br />included for insertion into Volume 4. <br />