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CITY OF EVERETT STORMWATER MANAGEMENT MANUAL <br />Design and Installation Specifications <br />See DCSS Drawing #201 for details. Note: the 100 foot minimum length of the entrance shall be reduced <br />to the maximum practicable size when the size or configuration of the site does not allow the full length <br />(100 feet). <br />1. A separation geotextile shall be placed under the spalls to prevent fine sediment from pumping up <br />into the rock pad. The geotextile shall meet the following standards: <br />a. Grab Tensile Strength (ASTM D4751): 200 psi minimum <br />b. Grab Tensile Elongation (ASTM D4632): 30 percent maximum <br />c. Mullen Burst Strength (ASTM D3786-80a): 400 psi minimum <br />d. AOS (ASTM D4751): 20 to 45 (U.S. standard sieve size). <br />2. Hog fuel (wood -based mulch) may be substituted for or combined with quarry spalls in areas that <br />will not be used for permanent roads. Hog fuel is generally less effective at stabilizing <br />construction entrances and should be used only at sites where the amount of traffic is very <br />limited. Hog fuel is not recommended for entrance stabilization in urban areas. The <br />effectiveness of hog fuel is highly variable and it generally requires more maintenance than <br />quarry spalls. The inspector may at any time require the use of quarry spalls if the hog fuel is not <br />preventing sediment from being tracked onto pavement or if the hog fuel is being carried onto <br />pavement. Hog fuel is prohibited in permanent roadbeds because organics in the subgrade soils <br />cause degradation of the subgrade support over time. <br />3. Fencing (see BMP C 103) shall be installed as necessary to restrict traffic to the construction <br />entrance. <br />4. Whenever possible, the entrance shall be constructed on a firm, compacted subgrade. This can <br />substantially increase the effectiveness of the pad and reduce the need for maintenance. <br />Maintenance Standards <br />1. Quarry spalls (or hog fuel) shall be added if the pad is no longer in accordance with the <br />' specifications. <br />2. If the entrance is not preventing sediment from being tracked onto pavement, then alternative <br />measures to keep the streets free of sediment shall be used. This may include an increase in the <br />dimensions of the entrance or the installation of a wheel wash. <br />3. Any sediment that is tracked onto pavement shall be removed by shoveling or street sweeping. <br />The sediment collected by sweeping shall be removed or stabilized on site. The pavement shall <br />not be cleaned by washing down the street, except when sweeping is ineffective and there is a <br />threat to public safety. If it is necessary to wash the streets, the construction of a small sump shall <br />be considered. The sediment would then be washed into the sump where it can be controlled. <br />4. Any quarry spalls that are loosened from the pad, which end up on the roadway shall be removed <br />immediately. <br />' 5. If vehicles are entering or exiting the site at points other than the construction entrance(s), fencing <br />(see BMP C103) shall be installed to control traffic. <br />6. Upon projectcompletion and site stabilization, all construction accesses intended as permanent <br />access for maintenance shall be permanently stabilized. <br />Volume ll — Construction Stormwater Pollution Prevention <br />3-5 <br />