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The erosion and sediment control industry has grown dramatically primarily because of concerns regarding the conservation of topsoil and surface water pollution. In both cases, the goal is to stop the movement of soil particles by covering or vegetating an exposed area or by blocking soil movement with a physical barrier. Most people would characterize erosion control with the roadside application of a green hydromulch which may be blended with seed, fertilizer, and lime. The wood or recycled paper based hydromulches cover the soil surface holding particles in their place while acting as a water absorbent medium for seed germination. In many areas around the Country, both dry seeding and hydroseeding are followed up with an application of hay or straw, which is blown through a mechanized unit onto the soil surface. The straw or hay may then be crimped into the soil surface or glued together with a "tackfier" to keep it from moving. In severely sloped areas, degradable and non-degradable erosion control blankets are used to hold soil in place until vegetation is established. Erosion control blankets are typically stapled onto the soil surface. In all three of these cases, the short-term goal is to physically hold the soil in place while the long-term goal is to establish a dense vegetative cover.
In many cases, erosion and sediment control techniques are not differentiated because of their similar goals. Regardless of the name, both erosion and sediment control have become significant issues associated with construction projects. In many cases, not only do states have erosion and sediment control guidelines, but counties within a state may also. Typically, more environmentally progressive states and more environmentally sensitive areas posses stricter erosion and sediment control regulations.
Although many erosion and sediment control techniques and products exist, many are used inappropriately or not installed properly, and therefore do not function optimally. Other techniques and products are extremely functional, yet very expensive. For instance, it is common for contractors who perform hydroseeding or straw blowing in conjunction with seeding to cheat and use less than the prescribed quantities of materials required to obtain optimum results. It is common for lower rates of seed, hydroseeding mulch, and straw to be applied on the affected area than specified by the customer or specifying agency. Also, on extreme slopes and areas of heavy water flow, these two techniques are not the most effective. The use of silt fencing is a common practice on roadsides and construction sites to block the movement of sediment into catch basins drop inlet openings, or culvert inlets. However, they are often not installed properly. A properly installed silt fence, which is a tightly woven fabric attached to posts, requires the base of the filter fabric to be placed into a trench and backfilled to secure it in place. By burying the base of the filter fabric, no sediment can travel under the silt fencing. Unfortunately the base of the filter fabric is often not buried because of the labor-intensive nature of the process. The bottom line is that the use of compost and other organic type mulch materials can be more functional, less expensive, and/or better for the environment than current erosion and sediment control techniques.
Organic Soil Mulches in Erosion & Sediment Control
Benefits: Page 1
Benefits: Page 2
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