Section 003. Definitions

The terms “Department,” “Director,” and “Waters” are defined in Section 39-103, Idaho Code. The term “Groun d water” (Groundwater) is defined in Section 39-121, Idaho Code. (7-1-25) 01. Abandoned System. A system that no longer receives blackwaste or wastewater due to diversio n to another treatment system or due to termination of waste flow for more than two (2) years. (7-1-25) 02. Absorption Bed. A drainfield excavation exceeding six (6) feet in width. (7-1-25) 03. Alternative System. Any system other than a standard system for which the Department has issue d design guidelines or the Director determines is a modification of a standard system. (7-1-25) a. A basic alternative system is any capping fill system, extra drainrock trench, gravelless trenc h system, steep-slope system, or other system specified in the TGM. (7-1-25) b. A complex alternative system is any evapotranspiration system, ETPS, lagoon system, LSAS , pressure distribution system, PWTP system, intermittent sand filter, sand mound, or other system specified in th e TGM. (7-1-25) 04. Bedroom. A habitable room within a dwelling that meets state or local building code requirement s applicable to bedrooms and includes methods of ingress and egress. The local building authority may designate an y additional room as a bedroom. (7-1-25) 05. Blackwaste. As defined in IDAPA 58.01.16, Wastewater Rules. (7-1-25) 06. Blackwater. As defined in IDAPA 58.01.16, Wastewater Rules. (7-1-25) 07. Building Sewer. The extension of the building drain beginning five (5) feet outside the inner fac e of the building wall. (3-31-22) 08. Central System. Any system that receives blackwaste or wastewater in volumes exceeding twenty- five hundred (2,500) gallons per day; any system that receives blackwaste or wastewater from more than two (2 ) dwelling units or more than two (2) buildings under separate ownership. (7-1-25) 09. Construct. To make, form, excavate, alter, expand, repair, or install a system. (7-1-25) 10. Drainfield

08. Central System. Any system that receives blackwaste or wastewater in volumes exceeding twenty- five hundred (2,500) gallons per day; any system that receives blackwaste or wastewater from more than two (2 ) dwelling units or more than two (2) buildings under separate ownership. (7-1-25) 09. Construct. To make, form, excavate, alter, expand, repair, or install a system. (7-1-25) 10. Drainfield. A system of aggregate-filled trenches, gravelless chamber systems, drip systems , absorption beds, or other approved subsurface dispersal methods that distribute wastewater effluent into the soil. Als o known as a “leachfield” or “soil absorption system.” (7-1-25) 11. Dwelling Unit. A single unit with complete independent living facilities for one (1) or mor e persons, including permanent improvements for living, sleeping, eating, cooking, and sanitation. (7-1-25) 12. Existing System. Any system installed before the effective date of these rules. (7-1-25) 13. Expand. To enlarge any nonfailing system. (3-31-22) 14. Extended Treatment Package System (ETPS). A wastewater treatment product that requires electricity and provides secondary or tertiary wastewater treatment to septic tank effluent for systems receiving les s than twenty-five hundred (2,500) gallons per day. (7-1-25) 15. Failing System. Any system that exhibits one (1) or more of the following characteristics:(7-1-25) a. Does not meet the intent stated in Subsection 004.01. (7-1-25) b. Fails to accept blackwaste and wastewater; or (7-1-25) c. Discharges blackwaste or wastewater into the waters or onto the ground surface. (7-1-25) 16. Gray Water. As defined in IDAPA 58.01.16, Wastewater Rules. (7-1-25) 17. High Groundwater Level -- Normal, Seasonal. High groundwater level may be established b y the soil characteristics, actual groundwater monitoring, or historic records. (7-1-25) a. Normal high groundwater level is the highest elevation of groundwater that is maintained o r exceeded continuously for six (6) weeks a year. (7-1-25) b

Water. As defined in IDAPA 58.01.16, Wastewater Rules. (7-1-25) 17. High Groundwater Level -- Normal, Seasonal. High groundwater level may be established b y the soil characteristics, actual groundwater monitoring, or historic records. (7-1-25) a. Normal high groundwater level is the highest elevation of groundwater that is maintained o r exceeded continuously for six (6) weeks a year. (7-1-25) b. The seasonal high groundwater level is the highest elevation of groundwater that is maintained or exceeded continuously for one (1) week a year. (7-1-25) 18. Individual System. Any standard, alternative, or subsurface disposal system that is not a centra l system. (7-1-25) 19. Install. To excavate or put in place a system or component of a system. (7-1-25) 20. Installer. Any person, corporation, or firm engaged in the business of excavation or construction o f individual or subsurface sewage disposal systems in the State. (7-1-25) 21. Large Soil Absorption System (LSAS). A subsurface sewage disposal system designed to receiv e two thousand five hundred (2,500) gallons of wastewater or more per day, including where the total wastewater flo w from the entire proposed project exceeds two thousand five hundred (2,500) gallons per day, but is separated int o absorption modules that receive less than two thousand five hundred (2,500) gallons per day. (7-1-25) 22. Limiting Layer. A subsurface layer or material that severely limits the capability of the soil to treat or absorb wastewater including, but not limited to, water tables, fractured bedrock, excessively permeable material , and impermeable material. (7-1-25) 23. Manufactured Medium Sand. Sand that meets the following gradation requirements: Manufactured medium sand allowable particle size percent composition. Sieve Size Passing (%) 4 95–100 8 80–100 16 50–85 30 25–60 50 10–30 100 2–10 200 <2 (3-31-22) 24. Minimum Tank Capacity. The minimum required total liquid capacity of the septic tank facility. (7-1-25) 25. New System

mpermeable material. (7-1-25) 23. Manufactured Medium Sand. Sand that meets the following gradation requirements: Manufactured medium sand allowable particle size percent composition. Sieve Size Passing (%) 4 95–100 8 80–100 16 50–85 30 25–60 50 10–30 100 2–10 200 <2 (3-31-22) 24. Minimum Tank Capacity. The minimum required total liquid capacity of the septic tank facility. (7-1-25) 25. New System. A system that is or might be approved on or after the effective date of these rules. (7-1-25) 26. Nondischarging System. Any system designed and constructed to prevent subsurface discharge o f blackwaste or wastewater. (7-1-25) 27. Pollutants. As defined in IDAPA 58.01.16, Wastewater Rules. (7-1-25) 28. Proprietary Wastewater Treatment Product (PWTP). A manufactured product that provides passive treatment to septic tank effluent for systems receiving less than twenty-five hundred (2,500) gallons per day. (7-1-25) 29. Repair. To remake, reform, replace, or enlarge a failing system, or any component as is necessar y to restore proper operation. (7-1-25) 30. Scarp. The side of a hill, canyon, ditch, river bank, roadcut, or other geological featur e characterized by a slope of forty-five (45) degrees (100% slope) or more from the horizontal. (7-1-25) 31. Septic Tank. A watertight, covered receptacle designed and constructed to receive wastewate r discharge, separate solids from liquid, digest organic matter, store digested solids through a period of detention, an d allow clarified liquids to discharge for final disposal. (7-1-25) 32. Septic Tank Facility. A septic tank or series of septic tanks preceding a subsurface disposa l system. Tanks or compartments used for housing pretreatment products or used as dosing chambers are no t considered part of the septic tank facility. (7-1-25) 33. Septage. As defined in IDAPA 58.01.16, Wastewater Rules. (7-1-25) 34. Service Provider

d liquids to discharge for final disposal. (7-1-25) 32. Septic Tank Facility. A septic tank or series of septic tanks preceding a subsurface disposa l system. Tanks or compartments used for housing pretreatment products or used as dosing chambers are no t considered part of the septic tank facility. (7-1-25) 33. Septage. As defined in IDAPA 58.01.16, Wastewater Rules. (7-1-25) 34. Service Provider. Any person, corporation, or firm engaged in the business of providing operation , maintenance, and monitoring of complex alternative systems in the state of Idaho. (3-31-22) 35. Sewage. As defined in IDAPA 58.01.16, Wastewater Rules. (7-1-25) 36. Standard System. An effluent sewer, one (1) or more aggregate filled trenches, and a gravity flo w wastewater distribution system. (7-1-25) 37. Subsurface Disposal System. Any system with a point of discharge beneath the earth’s surface. (7-1-25) 38. Surface Water - Intermittent, Permanent, Temporary. (3-31-22) a. Any waters including but not limited to, lakes, streams, canals, and ditches. (7-1-25) b. Intermittent surface water exists continuously for more than two (2) months but not more than si x (6) months a year. (7-1-25) c. Permanent surface water exists continuously for more than six (6) months a year. (7-1-25) d. Temporary surface water exists continuously for less than two (2) months a year. (7-1-25) 39. System. Beginning at the point of entry, physically connected piping, treatment devices , receptacles, structures, or areas of land designed, used or dedicated to convey, store, stabilize, neutralize, treat, o r dispose of blackwaste or wastewater. (7-1-25) 40. Trench. A drainfield excavation six (6) feet or less in width. (7-1-25) 41. Wastewater. As defined in IDAPA 58.01.16, Wastewater Rules. (7-1-25)