Utah Admin. Code R317-4-2 - Definitions

(1) "Absorption area" means the entire area used for the subsurface treatment and dispersion of effluent by an absorption system.

(2) "Absorption bed" means an absorption system consisting of large excavated areas utilizing drain media or chambers.

(3) "Absorption system" means a covered system constructed to receive and to disperse effluent, from gravity or a pump, in such a manner that the effluent is effectively filtered and retained below the ground surface.

(4) "Absorption trench" means an absorption system consisting of a series of narrow excavated trenches utilizing drain media, chambers, or bundled synthetic aggregate units.

(5) "Alternative onsite wastewater system" means an onsite wastewater system that is not a conventional onsite wastewater system.

(6) "At-grade system" means an alternative onsite wastewater system where the bottom of the absorption system is placed at or below the elevation of the existing site grade, and the top of the distribution pipe is above the elevation of existing site grade, and the absorption system is contained within fill that extends above that grade.

(7) "Barrier material" means an effective, pervious material such as an acceptable synthetic filter fabric, or a two-inch layer of compacted straw.

(8) "Bedrock" means the rock, usually solid, that underlies soil or other unconsolidated, superficial material.

(9) "Bedroom" means any portion of a dwelling that is so designed as to furnish the minimum isolation necessary for use as a sleeping area. It may include a den, study, sewing room, or sleeping loft. Unfinished basements shall be counted as a minimum of one additional bedroom.

(10) "Body politic" means the state or its agencies or any political subdivision of the state to include a county, city, town, improvement district, taxing district or other governmental subdivision or public corporation of the state.

(11) "Building sewer" means the pipe that carries wastewater from the building to a public sewer, an onsite wastewater system or other point of dispersal. It is synonymous with "house sewer."

(12) "Bundled synthetic aggregate trench" means an absorption trench utilizing bundled synthetic aggregate units.

(13) "Bundled synthetic aggregate unit" means a cylindrically shaped manufactured unit of synthetic aggregate enclosed in polyolefin netting, which may contain a perforated pipe.

(14) "Chamber" means an open bottom, chambered structure of an approved material and design.

(15) "Chambered trench" means an absorption trench utilizing chambers.

(16) "Cleanout" means a device designed to provide access for removal of deposited or accumulated materials, generally from a pipe.

(17) "Closed loop distribution" means a distribution method where the absorption system layout has the inlet and outlet ends of each lateral connected creating a complete and continuous pathway for effluent flow.

(18) "Coarse drain media" means drain media ranging from 3/4 to 12 inches in diameter.

(19) "Condominium" means the ownership of a single unit in a multi-unit project together with an undivided interest in common, in the common areas and facilities of the property.

(20) "Connecting trench" means an absorption trench that is used to connect other absorption trenches, is less than 20 feet in length, and may be used to calculate total required absorption area.

(21) "Construction permit" means the permit that authorizes an onsite wastewater system to be installed according to an approved design. An additional construction permit may also authorize activities associated with the repair or alteration of a malfunctioning or failing system.

(22) "Conventional onsite wastewater system" means an onsite wastewater system typically consisting of a building sewer, a septic tank, and an absorption system utilizing absorption trenches, absorption beds, deep wall trenches, or seepage pits.

(23) "Cover" means soils used to overlay the absorption area that is free of large stones 10 inches diameter or larger, frozen clumps of earth, masonry, stumps, or waste construction material, or other materials that could damage the system.

(24) "Curtain drain" means any ground water interceptor or drainage system that is backfilled with gravel or other suitable material and is intended to interrupt or divert the course of shallow ground water or surface water away from the onsite wastewater system.

(25) "Designer" means a person who fulfills the requirements of Rule R317-11.

(26) "Deep wall trench" means an absorption system consisting of deep excavated trenches utilizing coarse drain media, with a minimum sidewall absorption depth of 24 inches of suitable soil formation below the distribution pipe.

(27) "Distribution box" means a watertight structure that receives effluent and distributes it concurrently, in essentially equal portions, into two or more pipes leading to an absorption system.

(28) "Distribution pipe" means an approved pipe, solid or perforated, used in the dispersion of effluent in an absorption system.

(29) "Diversion valve" means a watertight structure that receives effluent through one inlet and distributes it to two or more outlets, only one of which is used at a time.

(30) "Domestic wastewater" means a combination of the liquid or water-carried wastes from residences, business buildings, institutions, and other establishments with installed plumbing facilities, excluding non-domestic wastewater. It is synonymous with the term "sewage."

(31) "Drain media" means media used in an absorption system. It shall consist of stone, crushed stone, or gravel, ranging from 3/4 to 2-1/2 inches in diameter. It shall be free from fines, dust, sand or organic material and shall be durable and inert so that it maintains its integrity, will not collapse or disintegrate with time. The maximum fines in the media shall be 2% by weight passing through a US Standard #10 mesh or 2 millimeter sieve. It shall be protected by a barrier material.

(32) "Drainage system" means all the piping within public or private premises that conveys sewage or other liquid wastes to a legal point of treatment and dispersal, but does not include the mains of a public sewer system or a public sewage treatment or disposal plant.

(33) "Drop box" means a watertight structure that receives septic tank effluent and distributes it into one or more distribution pipes, and into an overflow leading to another drop box and absorption system located at a lower elevation.

(34) "Dry wash" means the dry bed of an ephemeral stream that flows only after heavy rains and is often found at the bottom of a canyon.

(35) "Dwelling" means any structure, building, or any portion thereof that is used, intended, or designed to be occupied for human living purposes including houses, mobile homes, hotels, motels, and apartments.

(36) "Effluent" means the liquid discharge from any treatment unit including a septic tank.

(37) "Effluent pump" means a pump used to lift effluent.

(38) "Effluent sewer" means solid pipe that carries effluent to the absorption system.

(39) "Ejector pump" means a device to elevate or pump sewage to a septic tank, public sewer, or other means of disposal.

(40) "Ephemeral stream" means a stream that flows for a short period, a week or less, after a precipitation event.

(41) "Excessively permeable soil" means soils having an excessively high permeability, such as cobbles or gravels with little fines and large voids, and having a percolation rate faster than 1 minute per inch.

(42) "Experimental onsite wastewater system" means an onsite wastewater treatment and absorption system that is still in experimental use and requires further testing to provide sufficient information to determine its acceptance.

(43) "Filter fabric" means a synthetic, non-degradable woven or spun-bonded sheet material that has adequate tensile strength to prevent ripping during installation and backfilling, adequate permeability to allow free passage of water and gases; and adequate particle retention to prevent downward migration of soil particles into the absorption system. The minimum physical properties for the fabric shall be 4.0 ounces per square yard or equivalent.

(44) "Ground water" means that portion of subsurface water that is in the zone of soil saturation.

(45) "Ground water table" means the surface of a body of unconfined ground water in which the pressure is equal to that of the atmosphere.

(46) "Ground water table, perched" means unconfined ground water separated from an underlying body of ground water by an unsaturated zone. It is underlain by a restrictive strata or impervious layer. Perched ground water may be either permanent, where recharge is frequent enough to maintain a saturated zone above the perching bed, or temporary, where intermittent recharge is not great or frequent enough to prevent the perched water from disappearing from time to time as a result of drainage over the edge of or through the perching bed.

(47) "Gulch" means a small rocky ravine or a narrow gorge, especially one with an ephemeral stream running through it.

(48) "Gully" means a channel or small valley, especially one carved out by persistent heavy rainfall or an ephemeral stream.

(49) "Impervious strata" means a layer that prevents water or root penetration. In addition, it shall be defined as unsuitable soils or soils having a percolation rate slower than 60 minutes per inch for conventional systems.

(50) "Installer" means a qualified person with an appropriate contractor's license and knowledgeable in the installation or repair of an onsite wastewater system or its components.

(51) "Intermittent stream" means a stream that flows for a period longer than an ephemeral stream on a seasonal basis or after a precipitation event.

(52) "Invert" means the lowest portion of the internal cross section of a pipe or fitting.

(53) "Large Underground Wastewater Disposal System" means an onsite wastewater system that is designed to receive wastewater flows that may exceed more than 5,000 gallons per day, and may be designed to serve multiple dwelling units that are owned by separate owners except condominiums. A large underground wastewater disposal system usually consists of a building sewer, a septic tank and an absorption system.

(54) "Lateral" means a length of distribution pipe or chambered trenches in the absorption system.

(55) "Lot" means a portion of a subdivision, or any other parcel of land intended as a unit for transfer of ownership or for development or both and may not include any part of the right-of-way of a street or road.

(56) "Malfunctioning or failing system" means any onsite wastewater system that is not functioning in compliance with the requirements of this regulation and may include:

(a) any absorption system that seeps or flows to the surface of the ground or into waters of the state;

(b) any system that overflows from any of its components;

(c) any system that, due to failure to operate in accordance with its designed operation, causes backflow into any portion of a building drainage system;

(d) any system discharging effluent that does not comply with applicable effluent discharge standards;

(e) any leaking septic tank; or

(f) noncompliance with any standard stipulated on or by the construction permit, operating permit, or both.

(57) "Maximum ground water table" means the highest elevation that the top of the "ground water table" or "ground water table, perched" is expected to reach for any reason over the full operating life of the onsite wastewater system at that site.

(58) "Membrane Bioreactor" means an alternative onsite wastewater system that includes both biological processes and mechanical filtration processes to treat septic tank effluent before discharge to an absorption system. A membrane bioreactor unit includes a balance tank, an aeration tank, and a filtration tank. All tanks are interconnected with aeration pumps and recirculation lines.

(59) "Mound system" means an alternative onsite wastewater system where the bottom of the absorption system is placed above the elevation of the original site, and the absorption system is contained in a mounded fill body above that grade.

(60) "Non-closed loop distribution" means a distribution method where the absorption system layout has lateral ends that are not connected.

(61) "Non-domestic effluent" means the liquid discharge from any treatment unit including a septic tank that has a BOD5 equal or greater than 250 mg/L; or TSS equal to or greater than 145 mg/L; or fats, oils, and grease equal to or greater than 25 mg/L.

(62) "Non-domestic wastewater" means process wastewater originating from the manufacture of specific products. Such wastewater is usually more concentrated, more variable in content and rate, and requires more extensive or different treatment than domestic wastewater.

(63) "Non-public water source" means a culinary water source that is not defined as a public water source.

(64) "Non-residential" means a building that produces domestic wastewater, and is not a single-family dwelling.

(65) "Onsite wastewater system" means an underground wastewater dispersal system that is designed for a capacity of 5,000 gallons per day or less, and is not designed to serve multiple dwelling units that are owned by separate owners except condominiums. It usually consists of a building sewer, a septic tank and an absorption system.

(66) "Operating permit" means the permit that authorizes the operation and maintenance of an onsite wastewater system or wastewater holding tank. It may have a fee component that requires periodic renewal.

(67) "Packed bed media system" means an alternative onsite wastewater system that uses natural or synthetic media to treat wastewater. Biological treatment is facilitated via microbial growth on the surface of the media. The system may include a pump tank, a recirculation tank, or both.

(68) "Percolation rate" means the time expressed in minutes per inch required for water to seep into saturated soil at a constant rate during a percolation test.

(69) "Percolation test" means the method used to measure the permeability of the soil by measuring the percolation rate as described in this rule. This is sometimes referred to as a "perc test."

(70) "Permeability" means the rate at which a soil transmits water when saturated.

(71) "Pressure distribution" means a method designed to uniformly distribute effluent under pressure within an absorption system.

(72) "Public health hazard" means, for this rule, a condition whereby there are sufficient types and amounts of biological, chemical, or physical agents relating to water or sewage that are likely to cause human illness, disorders or disability. These may include pathogenic viruses and bacteria, parasites, toxic chemicals and radioactive isotopes. A malfunctioning onsite wastewater system constitutes a public health hazard.

(73) "Public water source" means a culinary water source, either publicly or privately owned, providing water for human consumption and other domestic uses, as defined in Title R309.

(74) "Pump tank" means a watertight receptacle equipped with a pump and placed after a septic tank or other treatment component.

(75) "Pump vault" means a device installed in a septic or pump tank that houses a pump and screens effluent with 1/8 inch openings or smaller before it enters the pump.

(76) "Recirculation tank" means the tank that receives, stores, and recycles partially treated effluent and recycles that effluent back through the treatment process or to the absorption area.

(77) "Regulatory authority" means either the Utah Division of Water Quality or the local health department having jurisdiction.

(78) "Replacement area" means sufficient land with suitable soil, excluding streets, roads, easements and permanent structures that complies with the setback requirements of this rule, and is intended for the 100% replacement of absorption systems.

(79) "Rotary tilling" means a tillage operation. Working land by plowing and harrowing to make land ready for cultivation, or employing power driven rotary motion of the tillage tool to loosen, shatter and mix soil.

(80) "Sand lined trench system" means an alternative onsite wastewater system consisting of a series of narrow excavated trenches utilizing sand media and pressure distribution.

(81) "Sand media" means sand fill meeting the ASTM C33/C33M - 11A Standard Specification for Concrete Aggregates.

(82) "Saprolite" means weathered material underlying the soil that grades from soft thoroughly decomposed rock to rock that has been weathered sufficiently so that it can be broken in the hands, cut with a knife or easily dug with a backhoe and is devoid of expansive clay. It has rock structure instead of soil structure and does not include hard bedrock or hard fractured bedrock.

(83) "Scarification" means loosening and breaking up of soil compaction in a manner that prevents smearing and maintains soil structure.

(84) "Scum" means a mass of sewage solids, which is buoyed up by entrained gas, grease, or other substances, floating on the surface of wastes in a septic tank.

(85) "Seepage pit" means an absorption system consisting of one or more deep excavated pits, either hollow-lined or filled, utilizing coarse drain media, with a minimum sidewall absorption depth of 48 inches of suitable soil formation below the distribution pipe.

(86) "Septage" means the semi-liquid material that is pumped out of a septic or pump tank, generally consisting of the sludge, liquid, and scum layer.

(87) "Septic tank" means a watertight receptacle that receives the discharge of a drainage system or part thereof, designed and constructed so as to retain solids, digest organic matter through a period of detention and allow the liquids to discharge into the soil outside of the tank through an absorption system.

(88) "Sequential distribution" means a distribution method in which effluent does not pass through an absorption area before it enters the succeeding areas through a distribution box or relief line allowing for portions of the absorption area to be isolated.

(89) "Serial distribution" means a distribution method in which effluent passes through an absorption area before entering the succeeding areas through a distribution box or relief line creating a single uninterrupted flow path.

(90) "Single-family dwelling" means a building designed to be used as a home by the owner or lessee of such building.

(91) "Sludge" means the accumulation of solids that have settled in a septic tank or a wastewater holding tank.

(92) "Slope" means the ratio of the rise divided by the run between two points, typically described as a percentage (rise divided by run multiplied by 100).

(93) "Soil exploration pit" means an open pit dug to permit examination of the soil to evaluate its suitability for absorption systems. This is also referred to as a "test pit."

(94) "Soil log" means a detailed description of soil characteristics and properties.

(95) "Soil structure" means the way in which the individual particles, sand, silt, and clay, are arranged into larger distinct aggregates called peds. The main types of soil structure are granular, platy, blocky, prismatic, and columnar. Soil may not have a visible structure because it is either single grain or massive.

(96) "Soil texture" means the percent of sand, silt, and clay in a soil mixture. Field methods for judging the texture of a soil are found in Subsection R317-4-14(3) Appendix C.

(97) "Standard trench" means an absorption trench utilizing drain media into which effluent is discharged through specially designed distribution pipes.

(98) "Suitable soil" means undisturbed soil that through textural and structural analysis or percolation rate meets the requirements for placement of an absorption system.

(99) "Test pit" see "soil exploration pit."

(100) "Unapproved system" means any onsite wastewater system that is deemed by the regulatory authority to be any:

(a) installation without the required regulatory oversight, permits, or inspections;

(b) repairs to an existing system without the required regulatory oversight, permits, or inspections; or

(c) alteration to an existing system without the required regulatory oversight, permits, or inspections.

(101) "USDA system of classification" means the system of classifying soil texture used by the United States Department of Agriculture.

(102) "Wastewater" means sewage, industrial waste or other liquid substances that might cause pollution of waters of the state. Intercepted ground water that is uncontaminated by wastes is not included.

(103) "Wastewater holding tank" means a watertight receptacle designed to receive and store wastewater to facilitate treatment at another location.

(104) "Wind-blown sand" means sand that is formed by the weathering and erosion of sandstone typically found in sand-dune or sand-sheet deposits and is capable of producing sand and dust storms when disturbed.

Notes

Utah Admin. Code R317-4-2

Amended by Utah State Bulletin Number 2016-1, effective 1/1/2016 Amended by Utah State Bulletin Number 2023-14, effective 6/29/2023