(A) Applicability. This applies to all land-disturbing activities within the MS4 jurisdiction with a land disturbance greater than or equal to one acre, or disturbances of less than one acre of land that are part of a larger common plan of development or sale if the larger common plan will ultimately disturb one or more acres of land.
(B) Exemptions. The requirements under this chapter do not apply to the following activities.
(1) Agricultural land-disturbing activities, including tillage, planting, cultivation, or harvesting operations to produce agricultural or nursery and vegetative crops, pasture renovation and establishment, the construction of agricultural conservation practices, and the installation and maintenance of agricultural drainage tile.
(2) Silvicultural activities associated with non-point discharges (40 CFR 122.27).
(3) Stormwater discharges associated with oil and gas exploration, production, processing or treatment operations, or transmission facilities (40 CFR 122.26).
(4) Ditch maintenance for activities performed on a regulated drain by a county drainage board as defined in Appendix B and I.C. 36-9-27.
(5) The land-disturbing activities listed below, provided other applicable permits contain provisions requiring immediate implementation of erosion and sediment control measures and stormwater management measures:
(a) Landfills that have been issued a certification of closure under 329 IAC 10;
(b) Coal-mining activities permitted under I.C. 14-34;
(c) Municipal solid waste landfills that are accepting waste per a permit issued by IDEM under 329 IAC 10 that contains equivalent stormwater requirements, including the expansion of landfill boundaries and construction of new cells, either within or outside the original solid waste permit boundary;
(d) The Indiana Department of Transportation when it conducts its business within the county corporate limits.
(6) Any construction project that has had its final drainage plan approved by the county two years before the effective date of this chapter shall be exempt from all requirements of this chapter that exceed the requirements in effect at the time of approval.
(C) Discharges authorized by this chapter. This chapter authorizes the following discharges to waters of the state.
(1) Stormwater, including stormwater runoff, snowmelt runoff, and surface runoff and drainage, associated with construction activity (40 CFR § 122.26(b)(14) or § 122,26(b)(15)(i)).
(2) Stormwater discharges designated by IDEM as needing to obtain coverage under the CSGP (40 CFR § 122.26(a)(l)(v) or § 122.26(b)(15)(ii)).
(3) Stormwater discharges from construction support activities (e.g., concrete or asphalt batch plants, equipment staging yards, material storage areas, excavated material disposal areas, borrow areas), provided the support activity is directly related to the construction site required to have coverage for stormwater discharges; and:
(a) The support activity is not a commercial or industrial operation, nor does it serve multiple unrelated construction projects;
(b) The support activity does not continue to operate beyond the completion of the construction activity for the project it supports; and
(c) Stormwater measures are implemented per the stormwater pollution prevention plan, performance standards, and the Stormwater Management approval.
(4) Non-stomiwater discharges or flows, provided they are not identified by IDEM as significant sources of pollutants to waters of the state, including, but not limited to:
(a) Emergency fire-fighting water;
(b) Fire-hydrant-flushing water;
(c) Landscape-irrigation water;
(d) Water-line-flushing water;
(e) Routine, external, building-washdown water that does not use detergents;
(f) Water used to wash vehicles and equipment that does not contain soaps, solvents, or detergents;
(g) Uncontaminated, non-turbid discharges of ground water or spring water;
(h) Foundation or crawl space footing drainages where flows are not contaminated with process materials such as solvents or contaminated groundwater;
(i) Uncontaminated condensate from air-conditioning units, coolers, and other compressors, and from outside refrigerated gases or liquids;
(j) Construction dewatering that has been treated by an appropriate stormwater quality measure or series of measures, provided other contaminants are not present.
(BC Ord. 2024-09, passed 7-8-24)