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effects the model for the "SAE Topsoil Stockpile, Straw Bales and Ground Litter Filter" and "Lone Pine Gulch Staging Area, Fill Slope". D. It appears that culvert H will discharge water into the east riprap ditch or through the vegetation filter at the staging area. If either is the case, the additional runoff should be accounted for in the model. E. The Division disagrees with the statement on page 5 of the demonstration, which reads the value for the staging area pad is not required to develop the SAE analyses. As Enclosure 8 is modeling a disturbed area, the runoff from this area is required to meet effluent limitations. The notation should be removed. F. The Division's experience and conversations with Richard Warner have established that the porous rock check dam in SEDCAD is probably not adequate to model the performance of silt fences and hay bales. To our knowledge, there is not another model that will accurately model these structures. This is evident in the model for the SAE topsoil stockpile; the haybales/siltfence have a trap efficiency of zero percent. Therefore, it has been the Division's policy to require occasional sampling in these areas. If there is concentrated flow, MCC should commit to taking a sample prior to the water going through the vegetation filter. This commitment should be included in the permit. G. The best management practices (BMPs) as described on Enclosure 2 and 3 of the demonstration should be in place prior to construction initiation. It may be impractical for MCC to install the required BMPs until construction is completed. However, MCC should consider interim sediment control measures. Please specify the interim measures MCC will employ. Please verify that approved and properly functioning control features will be in place during all phases of the project. H. MCC should commit to performing routine inspections of the sediment control structures to ensure that they are functioning properly. If structures are missing or have deteriorated, the area may be subject to an enforcement action. The commitment should be included in the permit. I. The SAE section of the permit, page 2.05-37, should be updated with the new SAE demonstration or refer to Exhibit 66.