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DocuSign Envelope ID:AEB4824B-973E-408D-9C1C-5EDDD8B50786 Attachment B - NCDEQ Permanent Seeding Specs <br /> Practice Standards and Specifications <br /> 6.11 <br /> PERMANENT SEEDING <br /> PS <br /> Definition Controlling runoff and erosion on disturbed areas by establishing perennial <br /> vegetative cover with seed. <br /> Purpose To reduce erosion and decrease sediment yield from disturbed areas, to <br /> permanently stabilize such areas in a manner that is economical,adapts to site <br /> conditions,and allows selection of the most appropriate plant materials. <br /> Conditions Where Fine-graded areas on which permanent, long-lived vegetative cover is the <br /> Practice Applies most practical or most effective method of stabilizing the soil. Permanent <br /> seeding may also be used on rough-graded areas that will not be brought to <br /> final grade for a year or more. <br /> Areas to be stabilized with permanent vegetation must be seeded or planted <br /> within 15 working days or 90 calendar days after final grade is reached,unless <br /> temporary stabilization is applied. <br /> Introduction During the initial phase of all land disturbing projects,the protective layer,either <br /> natural or man-made, is removed from the earth's surface. As the protective <br /> layer is removed, the resulting bare areas are exposed to the natural forces <br /> of rainfall, freezing, thawing, and wind. The result is soil erosion that leads <br /> to sediment pollution of North Carolina streams,rivers, lakes, and estuaries. <br /> This design manual presents many alternative strategies for preventing erosion <br /> and reducing sediment loss during the construction process. Establishment <br /> of protective vegetative cover during the construction project, however, is <br /> the crucial step in achieving soil stabilization, controlling soil erosion, and <br /> preventing sedimentation ofwaterways.Without a sufficient amount ofroot mat <br /> and leaf cover to protect and hold the soil in place,large volumes of soil will be <br /> lost and waterways will be degraded long after prof ects are considered complete. <br /> Sections of this practice standard address many of these various situations <br /> and set forth selection criteria for the appropriate cover based on purpose and <br /> adaptability. Some sediment and erosion control practices recommended in <br /> earlier editions of the manual may no longer be applicable. For example,many <br /> popular and commonly used seed and plant varieties have been identified as <br /> invasive. Invasive plants are defined as species that aggressively compete <br /> with, and displace, locally adapted native plant communities. In select cases <br /> where no practical alternative is available,these plants may be considered on <br /> a limited basis for soil stabilization,understanding that the goal is to eliminate <br /> the use of all invasive plants in favor of non-invasive native and/or introduced <br /> species that will provide an equally acceptable vegetative cover. Where there is <br /> no alternative to the use of invasive species,measures need to be incorporated <br /> in the installation and maintenance of these plants to limit their impacts. <br /> Rev.5/08 6.11.1 <br />