1029 52ND ST SW 2022-10-31 - Laserfiche WebLink

4. SWPPP NARRATIVE (MR #2) The intent of this section is to provide the information necessary to support the engineering plans to implement a design that will; reduce, eliminate or prevent the discharge of stormwater pollutants, meet or exceed the water quality and sediment management standards for the City and State, and prevent adverse impacts to the receiving waters for this project. Note; this narrative is intended to support the SWPPP that is included with the Targeted Drainage Plans also a part of this submittal package to the City. A. SITE!GRADING/EROSION CONTROL RISK ASSESSMENT Area proposed to be cleared/worked: 0.55 acres Average slope for the short plat: 10% (Area of Disturbance Only) Erosion Hazard of Soil Moderate Critical Areas downslope No Site is upstream of an ESA Stream No Based on the above information and the fact that the area of the short plat to be disturbed is moderate and construction site runoff will pass through silt fencing or other perimeter filtration features prior to leaving the short plat, and that if site conditions warrant, additional BMP's can be implemented as corrective measures the Risk Category for this site is Low-Moderate Risk. B.-SWPPP MINIMUM ELEMENTS 1: Preserve Vegetation and Mark Clearing Limits The first step in the.construction process is for the contractor to fence the limits of clearing/disturbance (BMP.C1.0.3) prior to any other construction activity. The engineering plans locate and provide the square footages for the areas of grading, clearing, impervious surfaces and un-disturbed areas on the proposed short plat. 0.55 acres of the site and frontage R/W will be cleared or disturbed for this project. 2: Establish Construction Access The SWPPP calls for the proposed construction entrance(BMP C105) to be installed as the second step after the staking of clearing limits. The construction entrance for this project will be along the southern property line in the back of Lot 4 and just east of Lot 3. At`this°utime winter work is-expected.Auring the wet season. 3: Control Flow Rates The runoff from site will be collected in interceptor swales and directed to a sediment trap that will discharge into the existing ditch system along the east side of this property and the west side of 51 st PI SW. Seatiursf 18-0727'SP Page 8 September 2019 .