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10 <br /> 2) Exceptions - this rule shall not apply in areas where <br /> it can be demonstrated that stormwater discharge <br /> velocities will not create an erosion problem in the <br /> receiving watercourse. <br /> 3) The following is a table of permissible velocity for <br /> stormwater discharges : <br /> Maximum Permissible <br /> Material Velocities f.p.s. M.P.S. <br /> Fine Sand (noncolloidal) 2 .5 .8 <br /> Sandy Loam (noncolloida] ) 2. 5 . 8 <br /> Silt Loam (noncolloidal) 3 .0 .9 <br /> Ordinary Firm Loam 3. 5 1. 1 <br /> Fine Gravel 5 . 0 1 . 5 <br /> Stiff Clay (very colloidal) 5.0 1. 5 <br /> Graded, Loam to Cobbles (noncolloidal) 5 .0 1.5 <br /> Graded, Silt to Cobbles (colloidal) 5. 5 1. 7 <br /> Alluvial Silts (noncolloidal) 3 .5 1 . 1 <br /> Alluvial Silts (colloidal) 5. 0 1. 5 <br /> Coarse Gravel (noncolloidal) 6 .0 1 . 8 <br /> Cobbles and Shingles 5.5 1. 7 <br /> Shale and. Hard Pans 6.0 1 . 8 <br /> Source : Adapted from recommendations by Special Committee on <br /> Irrigation Research, American Society of Civil Engi- <br /> neers, 1926, for channels with straight alignment. For <br /> sinuous channels, multiply allowable velocity by 0.95 <br /> for slightly sinuous, by 0 . 9 for moderately sinuous <br /> channels, and by 0 .8 for highly sinuous channels. <br /> Section 10 - Borrow and Waste Areas <br /> When the person conducting the land-disturbing activity is also <br /> the person conducting the borrow and waste disposal activity, <br /> areas from which borrow is obtained and which are not regulated <br /> by the provisions of the Mining Act of 1971, and waste areas for <br /> surplus materials other than landfills regulated by the Depart- <br /> ment of Human Resources, Division of Health Services, shall be <br /> considered as part of the land-disturbing activity where the <br /> borrow material is being used or from which the waste material. <br /> originated. When the person conducting the land-disturbing <br /> activity is not the person obtaining the borrow and/or disposing <br /> of the waste, these areas shall be considered a separate <br /> land-disturbing activity. <br /> Section 11 - Access and Haul Roads <br /> Temporary access and haul roads, other than public roads, con- <br /> structed or used in connection with any land-disturbing activity <br /> shall be considered a part of such activity. <br />