3214 BROADWAY BROADWAY KINECT APARTMENTS 2021-08-11

• • CITY OF EVERETT STORMWATER MANAGEMENT MANUAL • • 6. Organic matter is the most appropriate form of"fertilizer" because it provides nutrients • (including nitrogen,phosphorus,and potassium) in the least water-soluble form. A natural system typically releases 2 to 10 percent of its nutrients annually. Chemical fertilizers have since • been formulated to simulate what organic matter does naturally. • 7. In general, 10-4-6 N-P-K(nitrogen-phosphorus-potassium) fertilizer can be used at a rate of • 90 pounds per acre. Slow-release fertilizers should always be used because they are more • efficient and have fewer environmental impacts. It is recommended that areas being seeded for final landscaping conduct soil tests to determine the exact type and quantity of fertilizer needed. • This will prevent the over-application of fertilizer. Fertilizer should not be added to the • hydromulch machine and agitated more than 20 minutes before it is to be used. If agitated too much,the slow-release coating is destroyed. • 8. There are numerous products available on the market that takes the place of chemical fertilizers. • These include several with seaweed extracts that are beneficial to soil microbes and organisms. If • 100 percent cottonseed meal is used as the mulch in hydroseed,chemical fertilizer may not be • necessary. Cottonseed meal is a good source of long-term, slow-release,available nitrogen. 9. Hydroseed applications shall include a minimum of 1,500 pounds per acre of mulch with • 3 percent tackifier. Mulch may be made up of 100 percent: cottonseed meal; fibers made of • wood, recycled cellulose,hemp, and kenaf; compost; or blends of these. Tackifier shall be plant- • based, such as guar or alpha plantago,or chemical-based such as polyacrylamide or polymers. Any mulch or tackifier product used shall be installed per manufacturer's instructions. Generally, • mulches come in 40 to 50 pound bags. Seed and fertilizer are added at time of application. • 10. Mulch is always required for seeding. Mulch can be applied on top of the seed or simultaneously • by hydroseeding. • 11. On steep slopes, BFM or Mechanically Bonded Fiber Matrix(MBFM)products should be used. BFM/MBFM products are applied at a minimum rate of 3,000 pounds per acre of mulch with approximately 10 percent tackifier. Application is made so that a minimum of 95 percent soil • coverage is achieved. Numerous products are available commercially and should be installed per • manufacturer's instructions. Most products require 24 to 36 hours to cure before a rainfall and cannot be installed on wet or saturated soils. Generally, these products come in 40 to 50 pound • bags and include all necessary ingredients except for seed and fertilizer. • 12. BFMs and MBFMs have some advantages over blankets: • a. No surface preparation required • b. Can be installed via helicopter in remote areas • c. On slopes steeper than 2.5:1, blanket installers may need to be roped and harnessed for • safety • d. They are at least$1,000 per acre cheaper installed. • 13. In most cases,the shear strength of blankets is not a factor when used on slopes, only when used • in channels. BFMs and MBFMs are good alternatives to blankets in most situations where • vegetation establishment is the goal. a. When installing seed via hydroseeding operations, only about one-third of the seed • actually ends up in contact with the soil surface. This reduces the ability to establish a • good stand of grass quickly. One way to overcome this is to increase seed quantities by • up to 50 percent. • b. Vegetation establishment can also be enhanced by dividing the hydromulch operation • into two phases: • Volume II—Construction Stormwater Pollution Prevention • 3-10 • •