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• Roughening and Rototilling: <br />• The seedbed should be firm and rough. Roughen all soil no matter • <br />what the slope. Track walk slopes before seeding if engineering <br />purposes require compaction. Backblading or smoothing of slopes <br />greater than 4H:1 V is not allowed if they are to be seeded. <br />Restoration -based landscape practices require deeper incorporation <br />than that provided by a simple single -pass rototilling treatment. <br />Wherever practical, initially rip the subgrade to improve long-term <br />permeability, infiltration, and water inflow qualities. At a <br />minimum, permanent areas shall use soil amendments to achieve <br />organic matter and permeability performance defined in <br />engineered soil/landscape systems. For systems that are deeper <br />than 8 inches complete the rototilling process in multiple lifts, or <br />prepare the engineered soil system per specifications and place to <br />achieve the specified depth. <br />• Fertilizers: <br />Conducting soil tests to determine the exact type and quantity of <br />fertilizer is recommended. This will prevent the over -application <br />of fertilizer. <br />Organic matter is the most appropriate form of fertilizer because it <br />provides nutrients (including nitrogen, phosphorus, and potassium) <br />in the least water-soluble form. <br />In general, use 10-4-6 N-P-K (nitrogen -phosphorus -potassium) <br />fertilizer at a rate of 90 pounds per acre. Always use slow -release <br />fertilizers because they are more efficient and have fewer <br />environmental impacts. Do not add fertilizer to the hydromulch <br />machine, or agitate, more than 20 minutes before use. Too much <br />agitation destroys the slow -release coating. <br />There are numerous products available that take the place of <br />chemical fertilizers. These include several with seaweed extracts <br />that are beneficial to soil microbes and organisms. If 100 percent <br />cottonseed meal is used as the mulch in hydroseed, chemical <br />fertilizer may not be necessary. Cottonseed meal provides a good <br />source of long-term, slow -release, available nitrogen. <br />Bonded Fiber Matrix and Mechanically Bonded Fiber Matrix: <br />On steep slopes use Bonded Fiber Matrix (BFM) or Mechanically <br />Bonded Fiber Matrix (MBFM) products. Apply BFM/MBFM <br />products at a minimum rate of 3,000 pounds per acre of mulch <br />with approximately 10 percent tackifier. Achieve a minimum of 95 <br />percent soil coverage during application. Numerous products are <br />available commercially. Installed products per manufacturer's <br />instructions. Most products require 24-36 hours to cure before • <br />rainfall and cannot be installed on wet or saturated soils. <br />Volume II — Construction Stormwater Pollution Prevention - August 2012 <br />4-18 <br />