(A) A perimeter/outfall protection permit must be issued prior to breaking ground or disturbing soil in order to install sediment control practices at the hydrologic perimeter/outfall(s) of a construction site. The permit does not give permission to the permit holder to break ground or disturb soil on the entire construction site, as is granted through the approval and issuance of a storm water quality management permit.
(B) A perimeter/outfall protection permit is a predecessor to a storm water quality management permit. While plans for both permits are approved simultaneously, the provisions of a perimeter/outfall protection permit must be implemented, inspected, and accepted by the town prior to issuance of a storm water quality management permit.
(C) A perimeter/outfall protection permit may only be issued after the review and acceptance of a perimeter control plan.
(D) Securing the perimeter prior to any land disturbance will decrease sedimentation off-site once construction has begun. Perimeter protection shall focus on downstream points and outfall areas and does not necessitate protection of the entire site boundary. Efforts shall be focused on those areas where water flow is most likely to exit the project site.
(E) Clearing, except that necessary to establish sediment control devices shall not begin until all sediment control devices have been installed and have been stabilized. Sediment control devices prevent eroded soil from leaving the project site through the site perimeter or outfalls.
(F) Contractors shall install sediment control measures and regularly inspect and maintain the facilities throughout construction.
(G) Compliance with this subchapter requires that a grading plan be developed and submitted, a grading permit obtained, and a perimeter control plan be implemented before any clearing or stripping.
(H) (1) The perimeter control plan shall include measures to prevent sediment from leaving the site during initial disturbance activities and prior to temporary or permanent erosion prevention and/or sediment control practices.
(2) The perimeter control plan shall address downstream outfall points, while the grading plan defines site-wide erosion prevention and sediment control measures.
(3) The perimeter control plan shall address prevention of sediment deposition on properties adjacent to the project site. Utilizing well-vegetated buffer strips along lower perimeters, sediment barriers, filters, diversion berms, sediment basins, or other means accepted by the town may all be employed or combined to adequately protect adjacent properties.
(4) In selection of sediment control measures the type of flow, site terrain, soil type, and other relevant factors shall be considered. Buffer strips may only be utilized for sheet flow and must be at least 25 feet in width. If ineffective, a single sediment control device shall be supplemented with additional perimeter controls.
(5) The perimeter control plan shall address stabilizing construction entrances/exits to reduce the amount of sediment transported onto nearby roadways, and potentially into waterways. Where possible, traffic entering a public right-of-way, alley, sidewalk, or parking lot, traffic shall first pass over a stabilized stone pad. This pad shall be at least six inches thick, 100 feet long, and contain two- to three-inch crushed coarse graded stone. If operating under seasonally wet conditions and/or soft soils, filter fabric shall underlie the stabilized stone pad.
(6) The perimeter control plan shall address protection of outlets such as pipes, drains, culverts, conduits, or channels by significantly minimizing erosion and sedimentation through reduction of the velocity of flows from the project site. The placement of rock, grouted rip-rap, or concrete rubble at the outlet of a pipe to prevent scour of the soil around the culvert mouth caused by the high pipe flow velocities or similar measures are encouraged.
(I) Acceptance: site inspection and approval by the town must be received before any land disturbance or grading may proceed.
(1) The town shall make inspections of the site prior to the acceptance of the perimeter protection plan. Inspection will be performed within seven days after the submission of the plan and installation of the perimeter protection devices but before any disturbance or clearing has been performed. The inspector shall either approve the portion of work completed or shall advise the permittee as to the noncompliance with the perimeter protection plan as approved.
(2) Inspection of perimeter protection BMPs shall consist of a visual check list for each type of BMP, to ensure that each was designed and installed according to site specific conditions.
(3) Acceptance of the perimeter control plan and inspection of the appropriate BMPs shall compensate for and address any seasonal variations which may hinder the effectiveness of the BMPs. Seasonal variations may include changes in flow, hydrology, temperature, and vegetation. BMPs shall be designed according to these variations and appropriately to maintain a level of service.
(J) The state’s Department of Natural Resource’s guidance documents, including the Handbook for Erosion Control in Developing Areas, most current version or the Indiana Storm Water Quality Manual, should be reviewed and considered when preparing the perimeter control plan.
(K) The town reserves the right to develop or adopt other guidance documents to serve as design and implementation standards.
(Ord. G-12-02, passed 1-17-2012)