28-14 Amend Chp. 1339 Storm Water Mgmt

Home Browse Search

(5) On a site with a prior industrial land use or a site that is contaminated with gasoline, fuel oil, hydrocarbon based chemicals or other Ohio EPA regulated contaminates, the storm water is considered wastewater. A permit from Ohio EPA is required to address these sites. (6) Proper permits shall be obtained for development projects on solid waste landfill sites. (7) Paint, paint washing liquids, excess paints and other paint wastes are con- sidered solid wastes and shall be disposed of in accordance with applicable state regulations. Appropriate handling of these wastes shall occur at the site so as to prevent the discharge of these wastes into surface or ground waters. (8) Restroom facilities will be provided for site workers at all times that work- ers are present on the site and during all phases of the construction. (s) Storm Water Basins: All storm water basins shall be constructed in accord- ance with the Ohio Rainwater and Land Development manual. (t) Soil limitations shall be determined by using the current edition of the coun- ty soil survey written by the NRCS, USDA. 1339.10 POST - CONSTRUCTION MINIMUM STANDARDS. The permittee must adhere to all requirements of the current EPA Construction General Permit "Post- Construction Storm Water Management" section. Specific items of the Construction General Permit that the permittee should be aware of and adhere to include the water quality volume calculation, runoff coefficients based on the type of land use, and target drain times for structural post - construction BMPs. In addition, the permittee must also adhere to the following items: (a) Storm Water Detention. The Post - Construction BMP(s) chosen must be able to detain storm water runoff for protection of the stream channels, stream erosion control, and improved water quality. (b) Properly Sized BMPs. The BMP(s) chosen must be sized to treat the water quality volume (WQv) and ensure compliance with Ohio's Water Quality Standards in OAC Chapter 3745 -1. The WQv shall be equivalent to the volume of runoff from a 0.75 -inch rainfall. (c) Runoff Rate. The peak runoff rate from the development area shall not be greater after development than it was before development. The applicant shall provide calculations proving no increase in the runoff rates from the one (1), two (2), five (5), ten (10), twenty-five (25), fifty (50) and one hundred (100) year storms. (d) Runoff Volume. Increases in the runoff volume shall be offset by further restricting runoff rates. Where the land use will be mixed, the runoff coefficient should be calculated using a weighted average. Based on the increase in runoff volume, the applicant shall determine the critical storm for the development ar- ea. The runoff rate from the critical storm shall be restricted to the one (1) year pre- development storm runoff rate. The critical storm shall be calculated as fol- lows: 20