Administrative Rules of Montana › Department 17 - ENVIRONMENTAL QUALITY › Chapter 17.36 - SUBDIVISIONS/ON-SITE SUBSURFACE WASTEWATER TREATMENT › Subchapter 17.36.1 - Subdivision Application and Review › Rule 17.36.101 - DEFINITIONS

Current through Register Vol. 13, July 5, 2024
For purposes of subchapters 1, 3, 6, and 8, the following
				  definitions apply:
(1) "Accessory
				building" has the same meaning as defined in ARM
				17.38.101(3)(a).
(2) "Approved well drilling area" is an area
				or areas designated on a lot layout within which a well may be drilled. The
				area must meet all required well location setbacks, including those for well
				isolation zones.
(3) "Bedrock"
				means material that cannot be readily excavated by hand tools, or material that
				does not allow water to pass through or that has insufficient quantities of
				fines to provide for the adequate treatment and disposal of wastewater. The
				term does not include gravel and other rock fragments as defined in Department
				Circular DEQ-4, Appendix B.
(4)
				"Bedroom" means any room that is or may be used for sleeping. An unfinished
				basement is considered an additional bedroom.
(5) "Campground" is defined in
				50-52-101, MCA.
(6) "Certificate of survey" is defined in
				76-3-103, MCA.
(7) "Cesspool" means a seepage pit without a
				septic tank to pretreat the wastewater.
(8) "Commercial unit" means the area under
				one roof that is occupied by a business or other nonresidential use. A building
				housing two businesses is considered two commercial units.
(9) "Condominium" is defined in
				70-23-101, MCA.
(10) "Connection" means a line that provides
				water or sewer service to a single building or main building with accessory
				buildings. The term is synonymous with "service connection" as defined in ARM
				17.38.101. For purposes of ARM
				17.36.123, "connection" means a
				water or sewer line that connects a subdivision to a public system.
(11) "Department" means the Montana
				Department of Environmental Quality.
(12) "Deviation" means a department-approved
				departure from a requirement contained in a department circular.
(13) "Drainage way" means a course or channel
				along which storm water moves in draining an area.
(14) "Dry well" means a storm water detention
				structure that collects surface runoff and discharges the water below the
				natural ground surface.
(15)
				"Escarpment" means any slope greater than 50% that extends vertically six feet
				or more as measured from toe to top.
(16) "Existing system" means a water supply
				or wastewater disposal system that was installed prior to the submittal of a
				subdivision application under this subchapter.
(17) "Experimental system" means a wastewater
				treatment system for which specific design standards are not provided in
				Department Circular DEQ-4 or DEQ-2.
(18) "Facilities" means public or private
				facilities for the supply of water or disposal of sewage, storm water, or solid
				waste and any pipes, conduits, or other stationary method by which water, storm
				water, sewage, or solid wastes might be transported or distributed.
(19) "Fill" means artificially placed
				soil.
(20) "Floodplain" means the
				area adjoining the watercourse or drainway that would be covered by a flood
				that is expected to recur on the average of once every 100 years or by a flood
				that has a one percent chance of occurring in any given year. The floodplain
				consists of the floodway and the floodfringe, as defined in ARM
				36.15.101.
(21) "Gray water" means wastewater that is
				collected separately from sewage flow and that does not contain industrial
				chemicals, hazardous wastes, or wastewater from toilets.
(22) "Ground water monitoring" means
				measuring the depth from the natural ground surface to the seasonally high
				ground water performed in accordance with Department Circular DEQ-4.
(23) "Holding tank" means a watertight
				receptacle that receives wastewater for retention and does not as part of its
				normal operation dispose of or treat the wastewater. The term does not include
				surge tanks used in a gray water irrigation system if the system meets the
				requirements of ARM
				17.36.319 and Department Circular
				DEQ-4.
(24) "Impervious layer"
				means any layer of material in the soil profile that has a percolation rate
				slower than 240 minutes per inch.
(25) "Individual water system" means any
				water system that serves one living unit or commercial unit and that is not a
				public water supply system as defined in
				75-6-102, MCA.
(26) "Individual wastewater system" means a
				wastewater system that serves one living unit or commercial unit and that is
				not a public sewage system as defined in
				75-6-102, MCA.
(27) "Limiting layer" means bedrock, an
				impervious layer, or seasonally high ground water.
(28) "Living unit" means the area under one
				roof that can be used for one residential unit and that has facilities for
				sleeping, cooking, and sanitation. A duplex is considered two living
				units.
(29) "Local health officer"
				means health officer as defined in
				50-1-101, MCA, or the health
				officer's designee.
(30) "Lot" is
				synonymous with "tract" or "parcel" for purposes of this chapter.
(31) "Main" is defined in ARM
				17.38.101.
(32) "Mixing zone" is
				defined in
				75-5-103, MCA.
(33) "Mobile home" means a trailer equipped
				with necessary service connections that is designed for use as a long-term
				residence.
(34) "Multiple-user
				wastewater system" means a wastewater system that serves, or is intended to
				serve, more than two living units or commercial units or a combination of both
				and that is not a public sewage system as defined in
				75-6-102, MCA. In estimating the
				population that will be served by a proposed residential system, the reviewing
				authority shall multiply the number of living units by 2.5.
(35) "Multiple-user water supply system"
				means a water supply system that serves, or is intended to serve, more than two
				living units or commercial units or a combination of both and that is not a
				public water supply system as defined in
				75-6-102, MCA. In estimating the
				population that will be served by a proposed residential system, the reviewing
				authority shall multiply the number of living units by 2.5.
(36) "Municipal" means pertaining to an
				incorporated city or town.
(37)
				"Natural soil" means soil that has developed through natural processes and to
				which no fill material has been added.
(38) "Parcel" means a part of land which is
				created by a division of land. The term is synonymous with "tract" and "lot"
				for purposes of this chapter.
(39)
				"Permanent space" means a space, regardless of occupancy, for recreational
				camping vehicles or mobile homes, with facilities for the supply of water or
				disposal of sewage provided by individual hookups, a service building, or
				centralized dump stations for sewage or fill stations for water.
(40) "Plat" is defined in
				76-3-103, MCA.
(41) "Preliminary plat" is defined in
				76-3-103, MCA.
(42) "Professional engineer" means an
				engineer licensed or otherwise authorized to practice engineering in Montana
				pursuant to Title 37, chapter 67, MCA.
(43) "Public wastewater system" means a
				system for collection, transportation, treatment, or disposal of wastewater
				that serves 15 or more families or 25 or more persons daily for any 60 or more
				days in a calendar year. In estimating the population that will be served by a
				proposed residential system, the reviewing authority shall multiply the number
				of living units by 2.5, so that ten or more proposed residential connections
				will be considered a public system.
(44) "Public water supply system" means a
				system for the provision of water for human consumption from a community well,
				water hauler for cisterns, water bottling plant, water dispenser, or other
				water supply that has at least 15 service connections or that regularly serves
				at least 25 persons daily for any 60 or more days in a calendar year. In
				estimating the population that will be served by a proposed residential system,
				the reviewing authority shall multiply the number of living units by 2.5, so
				that ten or more proposed residential connections will be considered a public
				system.
(45) "Recreational camping
				vehicle" means a vehicular unit designed primarily as temporary living quarters
				for recreational, camping, travel, or seasonal use, and that either has its own
				power or is mounted on, or towed by, another vehicle. The basic types of RVs
				are camping trailer, fifth wheel trailer, motor home, park trailer, travel
				trailer, and truck camper.
(46)
				"Registered sanitarian" means a person licensed to practice the profession of
				sanitarian in Montana pursuant to Title 37, chapter 40, MCA.
(47) "Reviewing authority" is defined in
				76-4-102, MCA.
(48) "Seepage pit" means a covered
				underground receptacle that receives wastewater after primary treatment and
				allows the wastewater to seep into the surrounding soil.
(49) "Septic tank" means a wastewater
				settling tank in which settled sludge is in immediate contact with the
				wastewater flowing through the tank while the organic solids are decomposed by
				anaerobic action.
(50) "Sewage" is
				synonymous with "wastewater" for purposes of this chapter.
(51) "Shared wastewater system" means a
				wastewater system that serves, or is intended to serve, two living units or
				commercial units or a combination of both and that is not a public sewage
				system as defined in
				75-6-102, MCA.
(52) "Shared water system" means a water
				system that serves, or is intended to serve, two living units or commercial
				units or a combination of both and that is not a public water supply system as
				defined in
				75-6-102, MCA.
(53) "Site evaluation" means an evaluation to
				determine if a site is suitable for the installation of a subsurface wastewater
				treatment system.
(54) "Slope"
				means the rate that a ground surface declines in feet per 100 feet. It is
				expressed as percent of grade.
(55)
				"Soil profile" means a description of the soil strata to a depth of eight feet
				using the United States Department of Agriculture (USDA) soil classification
				system method, which can be found in Appendix B, Department Circular
				DEQ-4.
(56) "Spring" means natural
				opening in the earth's surface from which water issues or seeps.
(57) "State waters" is defined in
				75-5-103, MCA.
(58) "Subsurface wastewater treatment system"
				means the process of wastewater treatment in which the effluent is applied
				below the soil surface or into a mound by an approved distribution
				system.
(59) "Surface water" means
				any water on the earth's surface including, but not limited to, streams, lakes,
				ponds, reservoirs, and irrigation ditches, whether fresh or saline.
(60) "Tract" is synonymous with "lot" or
				"parcel" for the purposes of this chapter.
(61) "Unstable land forms" means areas
				showing evidence of mass down-slope movement such as hummock hill slopes,
				debris flows, landslides, and rock falls. Unstable land forms may be evidenced
				by slip surfaces roughly parallel to the hillside; landslide scars and carving
				debris ridges; fences, trees, or telephone poles which appear tilted; or tree
				trunks which bend uniformly as they enter the ground.
(62) "Waiver" means a department-approved
				departure from a requirement contained in department rules. Granting of waivers
				must be in accordance with ARM
				17.36.601.
(63) "Wastewater" means water-carried wastes.
				For purposes of these rules, wastewater does not include storm water. The term
				includes, but is not limited to, the following:
(a) household, commercial, or industrial
				wastes;
(b) chemicals;
(c) human excreta; or
(d) animal and vegetable matter in suspension
				or solution.