Administrative Rules of Montana › Department 17 - ENVIRONMENTAL QUALITY › Chapter 17.30 - WATER QUALITY › Subchapter 17.30.11 - Storm Water Discharges › Rule 17.30.1102 - DEFINITIONS

Current through Register Vol. 13, July 5, 2024
In this subchapter, the following terms have the meanings or
				  interpretations indicated below and shall be used in conjunction with and are
				  supplemental to those definitions contained in
				  75-5-103, MCA. If not defined in
				  this rule, terms used in this subchapter have the meanings set out in the
				  definitions in ARM Title 17, chapter 30, subchapter 13.
(1) "Best management practices (BMPs) "
				means schedules of activities, prohibitions of practices, maintenance
				procedures, and other management practices to prevent or reduce the pollution
				of state waters. BMPs also include treatment requirements, operating
				procedures, and practices to control plant site runoff, spillage or leaks,
				sludge or waste disposal, or drainage from raw material storage.
(2) "Discharge of a pollutant" and "discharge
				of pollutants" each means any addition of any pollutant or combination of
				pollutants to state waters from any point source. This definition includes
				additions of pollutants into water of the state from surface runoff that is
				collected or channeled by man and discharges through pipes, sewers, or other
				conveyances owned by a state, municipality, or other person that do not lead to
				a treatment works. This term does not include the addition of pollutants by an
				indirect discharger.
(3) "Discharge
				monitoring report (DMR) " means the department uniform form for the reporting
				of self-monitoring results by permittees.
(4) "Facility or activity" means any MPDES point source or any
				other facility or activity (including land or appurtenances thereto) that is
				subject to regulation under the MPDES program.
(5) "Final stabilization" means the time at which all
				soil-disturbing activities at a site have been completed and a vegetative cover
				has been established with a density of at least 70% of the pre-disturbance
				levels, or equivalent permanent, physical erosion reduction methods have been
				employed. Final stabilization using vegetation must be accomplished using
				seeding mixtures or forbs, grasses, and shrubs that are adapted to the
				conditions of the site. Establishment of a vegetative cover capable of
				providing erosion control equivalent to pre-existing conditions at the site
				will be considered final stabilization.
(6) "General permit" means an MPDES permit issued under ARM
				17.30.1341 authorizing a category
				of discharges under the Act within a geographical area.
(7) "Illicit discharge" means any discharge
				to a municipal separate storm sewer that is not composed entirely of storm
				water except discharges pursuant to an MPDES permit (other than the MPDES
				permit for discharges from the municipal separate storm sewer) and discharges
				resulting from fire fighting activities.
(8) "Infiltration" means water other than wastewater that enters a
				sewer system (including sewer service connections and foundation drains) from
				the ground through such means as defective pipes, pipe joints, connections, or
				manholes. Infiltration does not include inflow.
(9) "Inflow" means water other than wastewater that enters a sewer
				system (including sewer service connections) from sources including, but not
				limited to, roof leaders, cellar drains, yard drains, area drains, drains from
				springs and swampy areas, manhole covers, cross connections between storm
				sewers and sanitary sewers, catch basins, cooling towers, storm waters, surface
				runoff, street wash waters, or drainage. Inflow does not include
				infiltration.
(10) "Major municipal
				separate storm sewer outfall" or "major outfall" means a municipal separate
				storm sewer outfall that discharges from a single pipe with an inside diameter
				of 36 inches or more or its equivalent (discharge from a single conveyance
				other than circular pipe which is associated with a drainage area of more than
				50 acres); or, for municipal separate storm sewers that receive storm water
				from lands zoned for industrial activity (based on comprehensive zoning plans
				or the equivalent), an outfall that discharges from a single pipe with an
				inside diameter of 12 inches or more or from its equivalent (discharge from
				other than a circular pipe associated with a drainage area of two acres or
				more).
(11) "Montana pollutant
				discharge elimination system (MPDES) " means the system developed by the
				department for issuing permits for the discharge of pollutants from point
				sources into state waters. The MPDES is specifically designed to be compatible
				with the federal NPDES program established and administered by the
				EPA.
(12) "MS4" means a municipal
				separate storm sewer system.
(13)
				"Municipal separate storm sewer" means a conveyance or system of conveyances
				(including roads with drainage systems, municipal streets, catch basins, curbs,
				gutters, ditches, man-made channels, or storm drains) that discharges to
				surface waters and is:
(a) owned or operated
				by the state of Montana, a governmental subdivision of the state, a district,
				association, or other public body created by or pursuant to Montana law,
				including special districts such as sewer districts, flood control districts,
				drainage districts and similar entities, and designated and approved management
				agencies under section 208 of the federal Clean Water Act, which has
				jurisdiction over disposal of sewage, industrial wastes, storm water, or other
				wastes, and is:
(i) designed or used for
				collecting or conveying storm water;
(ii) not a combined sewer; and
(iii) not part of a publicly owned treatment works (POTW) as
				defined in ARM Title 17, chapter 30, subchapter 13.