Section 405 Management of Vegetation, Soils and Erosion Control
- A soils map, site plan, or grading plan that indicates designated soil management areas for all site soils, including, but not limited to:
- Soils that will be retained in place and designated as vegetation and soil protection areas (VSPAs).
- Topsoils that will be stockpiled for future reuse and the locations for the stockpiles.
- Soils that will be disturbed during construction and plans to restore disturbed soils and underlying subsoils to soil reference conditions.
- Soils that will be restored and re-vegetated.
- Soils disturbed by previous development that will be restored in place and re-vegetated.
- Locations for all laydown and storage areas, parking areas, haul roads and construction vehicle access, temporary utilities and construction trailer locations.
- Treatment details for each zone of soil that will be restored, including the type, source and expected volume of materials, including compost amendments, mulch and topsoil.
- A narrative of the measures to be taken to ensure that areas not to be disturbed and areas of restored soils are protected from compaction by vehicle traffic or storage, erosion, and contamination until project completion.
- A written erosion, sedimentation and pollutant control program for construction activities associated with the project. The program shall describe the best management practices (BMPs) to be employed including how the BMPs accomplish the following objectives:
- Prevent loss of soil during construction due to stormwater runoff or wind erosion, including the protection of topsoil by stockpiling for reuse.
- Prevent sedimentation of stormwater conveyances or receiving waters or other public infrastructure.
- Prevent polluting the air with dust and particulate matter.
- Prevent runoff and infiltration of other pollutants from construction site, including, but not limited to thermal pollution, concrete wash, fuels, solvents, hazardous chemical runoff, pH and pavement sealants. Ensure proper disposal of pollutants.
- Protect from construction activities the designated vegetation and soil protection areas, flood hazard areas and other areas of vegetation that will remain on site.
- A written periodic maintenance protocol for landscaping and stormwater management systems, including, but not limited to:
- A schedule for periodic watering of new planting that reflects different water needs during the establishment phase of new plantings as well as after establishment. Where development of the building site changed the amount of water reaching the preserved natural resource areas, include appropriate measures for maintaining the natural areas.
- A schedule for the use of fertilizers appropriate to the plants species, local climate and the preestablishment and post-establishment needs of the installed landscaping. Nonorganic fertilizers shall be discontinued following plant establishment.
- A requirement for a visual inspection of the site after major precipitation events to evaluate systems performance and site impacts.
- A schedule of maintenance activities of the stormwater management system including, but not limited to, cleaning of gutters, downspouts, inlets and outlets, removal of sediments from pretreatment sedimentation pits and wet detention ponds, vacuum sweeping followed by high-pressure hosing at porous pavement and removal of litter and debris.
- A schedule of maintenance activities for landscaped areas including, but not limited to, the removal of dead or unhealthy vegetation; reseeding of turf areas; mowing of grass to a height which optimizes lawn health and retention of precipitation.
MAXIMUM CONE PENETROMETER READINGS
|SURFACE RESISTANCE (PSI)||SUBSURFACE RESISTANCE (PSI)|
(includes loamy sand, sandy loam, sandy clay loam, and sandy clay)
(includes loam, silt loam, silty clay loam, and silty clay)
(includes clay loam)
- Sites that are prime farmland, unique farmland, or farmland of statewide importance.
- Greenfield sites where development is prohibited by Section 402.8.
Exception: Soils shall be permitted to be imported from the locations in Items 1 and 2 where those soils are a byproduct of a building and building site development process provided that imported soils are reused for functions comparable to their original function.
- Areas shall be cleared of debris including, but not limited to, building materials, plaster, paints, road base type materials, petroleum based chemicals, and other harmful materials;
- Areas of construction-compacted subsoil shall be scarified; and
- The first lift of replaced soil shall be mixed into this scarification zone to improve the transition between the subsoil and overlying soil horizons.
Exception: Scarification is prohibited in all of the following locations:
- Where scarification would damage existing tree roots.
- On inaccessible slopes.
- On or adjacent to trenching and drainage installations.
- On areas intended by the design to be compacted such as abutments, footings, inslopes.
- Other locations where scarification would damage existing structures, utilities and vegetation being preserved.
- Organic matter. To provide appropriate organic matter for plant growth and for water storage and infiltration, soils shall be amended with a mature, stable compost material so that not less than the top 12 inches (305 mm) of soil contains not less than 3 percent organic matter. Sphagnum peat or organic amendments that contain sphagnum peat shall not be used. Soil organic matter shall be determined in accordance with ASTM D 2974. Organic materials selected for onsite amendment or for blending of imported soils shall be renewable within a 50-year cycle.
- Additional soil restoration criteria. In addition to compliance with Item 1, soil restoration shall comply with not less than three of the following criteria:
- Compaction. Bulk densities within the root zone shall not exceed the densities specified in Table 405.1.2 and shall be measured using a soil cone penetrometer in accordance with ASAE S313.3. The root zone shall be not less than 12 inches (305 mm) nor less than the site's reference soil, whichever results in the greater depth of measurement. Data derived from a soil cone penetrometer shall be reported in accordance with ASAE EP542.
- Infiltration rates. Infiltration rates or saturated hydraulic conductivity of the restored soils shall be comparable to the site's reference soil. Infiltration rates shall be determined in accordance with ASTM D 3385 or ASTM D 5093. For sloped areas where the methods provided in the referenced standards cannot be used successfully, alternate methods approved by the code official shall be permitted provided that the same method is used to test both reference soil and onsite soil.
- Soil biological function. Where remediated soils are used, the biological function of the soils' mineralizable nitrogen shall be permitted as a proxy assessment of biological activity.
- Soil chemical characteristics. Soil chemical characteristics appropriate for plant growth shall be restored. The pH, cation exchange capacity and nutrient profiles of the original undisturbed soil or the site's reference soil shall be matched in restored soils. Salinity suitable for regionally appropriate vegetation shall be established. Soil amendments and fertilizers shall be selected from those which minimize nutrient loading to waterways or groundwater.
- Documentation, such as receipts from a soil, compost and amendments supplier, to demonstrate that techniques to restore soil occurred; and
- Soil test results to demonstrate that the selected techniques achieved the criteria of Section 405.1.4.2. Not less than two soil tests shall be conducted on the building site. For building sites where more than 8,000 square feet (744 m2) of soil is to be disturbed during construction, there shall be not less than one report for every 4,000 square feet (372 m2) disturbed or report frequency as determined by the registered design professional.
- Identification of existing vegetation located on a building site that is to be preserved and protected.
- Identification of portions of the building site to be designated as vegetation and soil protection areas (VSPAs) that are to be protected during the construction process from being affected by construction activities.
- Specification of methods to be used such as temporary fencing or other physical barriers to maintain the protection of the designated vegetation and soil protection areas (VSPAs).
- Specification of protected perimeters around trees and shrubs that are to be included in the designated vegetation and soil protection areas (VSPAs). Perimeters around trees shall be identified as a circle with a radius of not less than 1 foot (305 mm) for every inch (25 mm) of tree diameter with a radius of not less than 5 feet (1524 mm). The perimeters around shrubs shall be not less than twice the radius of the shrub.
Exception: Approved alternative perimeters appropriate to the location and the species of the trees and shrubs shall be permitted.
- Specification of methods to protect the viability of the designated vegetation and soil protection areas (VSPAs) to support the remaining vegetation at the conclusion of the construction process including minimizing impacts on the existing stormwater drainage patterns associated with the VSPAs.
- Identification of plans, methods and practices used to designate essential areas of soil and subsoil disturbance.