1622 E MARINE VIEW DR WHOLE SITE 2022-02-01

installed landscapes. Topsoil does not include any subsoils but only the material from the top several inches including organic debris. Conditions of Permanent landscaped areas shall contain healthy topsoil that reduces Use the need for fertilizers, improves overall topsoil quality, provides for better vegetal health and vitality, improves hydrologic characteristics, and reduces the need for irrigation. • Leave native soils and the duff layer undisturbed to the maximum extent practicable. Stripping of existing, properly functioning soil system and vegetation for the purpose of topsoiling during construction is not acceptable. Preserve existing soil systems in undisturbed and uncompacted conditions if functioning properly. • Areas that already have good topsoil, such as undisturbed areas, do not require soil amendments. • Restore, to the maximum extent practical, native soils disturbed during clearing and grading to a condition equal to or better than the original site condition's moisture -holding capacity. Use on -site native topsoil, incorporate amendments into on -site soil, or import blended topsoil to meet this requirement. • Topsoiling is a required procedure when establishing vegetation on shallow soils, and soils of critically low pH (high acid) levels. • . Beware of where the topsoil comes from, and what vegetation was on site before disturbance, invasive plant seeds may be included and could cause problems for establishing native plants, landscaped areas, or grasses. Topsoil from the site will contain mycorrhizal bacteria that are necessary for healthy root growth and nutrient transfer. These native mycorrhiza are acclimated to the site and will provide optimum conditions for establishing grasses. Use commercially available mycorrhiza products when using off -site topsoil. Design and Meet the following requirements for areas requiring disruption and Installation topsoiling: Specifications Maximize the depth of the topsoil wherever possible to provide the • maximum possible infiltration capacity and beneficial growth medium. Topsoil shall have: • A minimum depth of 8-inches. Scarify subsoils below the topsoil layer at least 4-inches with some incorporation of the upper material to avoid stratified layers, where feasible. Ripping or re- structuring the subgrade may also provide additional benefits regarding the overall infiltration and interflow dynamics of the soil • system. Volume II — Construction Stormwater Pollution Prevention - August 2012 4-29