2013-10-30_PERMIT FILE - C1981038A (2)

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The rainfall factor was determined from the SCS soil survey which indicated that precipitation averaged 39 centimeters in the paonia area. The soil erodibility factor was determined from the SCS soil survey for the Delson soil. The length and degree of slope was determined from design specifications. The cover management factor was determined from and evaluation of selected erosion control techniques (EPA 1979). The erosion control practice factor was determined from the publication Soil Erosion: Prediction and Control by the Soil Conservation Society of America. There are two areas where erosion will be controlled by alternate means other than by sedimentation ponds; the south facing outslope consisting of 2.70 acres and the north facing outslope consisting of 0.6 acres. The south facing outslope will have a twenty foot wide, near level but slightly • outsloping bench approximately half way in the total slope length. The percent slope of the outslopes will be 40 percent. The length of the south slope will be approximately 170 feet from the top of the bench to the mid- slope and approximately 180 feet from the mid-slope bench to the toe of the fill. The north outslope length will be approximately 160 feet. Erosion on the outslopes will be controlled by 1) proper sequencing topsoil salvage and replacement with construction, 2) immediately seeding and mulching topsoiled areas and 3) placing erosion control mats and silt fencing in strategic locations. It is anticipated that the fill will be half completed within two weeks after start of construction and that the south slope from the mid-level bench to the toe will have the topsoil in place ready for seeding and mulching. Possible erosion from this slope will be at • its highest at this time. If the assumption is made that seeding and mulching will not take place until 2 months from the initiation of construction then