Terms defined in SDCL 34A-2-2, have the same meaning when used in chapters 74:51:01 to 74:51:03, inclusive. Terms that are not defined must be construed in conformance with the context and in relation to the applicable section of the standards or the statute concerned. Terms used in chapters 74:51:01 to 74:51:03, inclusive, mean:

1. (1) "Attainable beneficial uses," those beneficial uses that can be achieved by the imposition of effluent limits required under §§ 74:51:01:07, 74:51:01:08, and 74:51:01:17 to 74:51:01:21, inclusive, and cost-effective and reasonable best management practices for nonpoint source control;
2. (2) "Aquatic life," an organism dependent on the water environment to either propagate or survive, or both;
3. (3) "Aquatic community," an association of interacting populations and stages of aquatic life in a given water body or habitat;
4. (4) "Best management practices," schedules of activities, prohibitions of practice, maintenance procedures, and other management practices to prevent or reduce the pollution of surface waters of the state on a voluntary basis, including treatment requirements, operating procedures, and practices to control site runoff, spillage or leaks, sludge, waste disposal, or drainage from raw material storage;
5. (5) "Bioaccumulative pollutants," pollutants that are taken up, retained, or accumulated in the bodies of organisms and are transferred by ingestion, in increasing concentrations in the predator organisms, to the point that one or more organisms in the food chain suffer significant harm;
6. (6) "Bioassay," a procedure in which the responses of organisms are used to detect or measure the presence or effect of one or more substances, wastes, effluents, or environmental factors, alone or in combination;
7. (7) "Biochemical oxygen demand," a standardized laboratory test used to determine the relative oxygen requirements of waters and wastewaters;
8. (8) "Biological integrity," the ability to support and maintain a balanced, integrated, adaptive community of organisms having a species composition, diversity, and functional organization comparable to that of the natural habitat of the region;
9. (9) "Black Hills Trout Management Area," all the waters in the Black Hills within the following boundary: from the South Dakota-Wyoming state line and the Redwater River (inclusive) to U.S. Highway 85, then south on U.S. Highway 85 to I-90, then southeast on I-90 to U.S. Highway 16T (16BinRapidCity), then south on U.S. Highway 16T to S.D. Highway 79, then south on S.D. Highway 79 to Maverick Junction, then west on Highway 18 to Edgemont, then northwest along the Burlington Northern Railroad to the South Dakota-Wyoming state line, then north along the state line to the point of the beginning;
10. (10) "Board," Water Management Board;
11. (11) "Coldwater marginal fish life propagation," a beneficial use assigned to surface waters of the state that support aquatic life and are suitable for stocked catchable-size coldwater fish during portions of the year, but which, because of critical natural conditions including low flows, siltation, or warm temperatures, are not suitable for a permanent coldwater fish population. Warmwater fish may also be present;
12. (12) "Coldwater permanent fish life propagation," a beneficial use assigned to surface waters of the state that are capable of supporting aquatic life and are suitable for supporting a permanent population of coldwater fish from natural reproduction or fingerling stocking. Warmwater fish may also be present;
13. (13) "Commerce and industry," a beneficial use assigned to surface waters of the state that are suitable for use as cooling water, industrial process water, navigation, and production of hydroelectric power;
14. (14) "Criterion," a designated concentration of a substance, measure of a physical factor, or narrative statement that, when not exceeded, will protect an organism, a biological community, or a prescribed beneficial use or water quality;
15. (15) "Designated beneficial uses," those beneficial uses specified in chapters 74:51:02 and 74:51:03 for each water body or segment, whether or not they are being attained;
16. (16) "Domestic water supply," a beneficial use assigned to surface waters of the state that are suitable for human consumption, culinary or food processing purposes, and other household purposes after suitable conventional treatment;
17. (17) "Epilimnion," the upper stratum of a water column, in a thermally-stratified waterbody;
18. (18) "Existing beneficial uses," uses actually attained in surface waters of the state on March 27, 1973, whether or not they are so designated;

19. (19) "Fish and wildlife propagation, recreation, and stock watering," a beneficial use classification assigned to all surface waters of the state that:

    1. (a) May support recreation, in and on the water, and fish and aquatic life, when sufficient quantities of water are present for sufficient duration to support those uses;
    2. (b) Provide habitat for aquatic and semiaquatic wild animals and fowl;
    3. (c) Provide natural food chain maintenance; and
    4. (d) Are of suitable quality for watering domestic and wild animals;
20. (20) "Geometric mean," the nth root of a product of n factors;
21. (21) "Handbook 69," Maximum Permissible Body Burdens and Maximum Permissible Concentrations of Radionuclides in Air and in Water for Occupational Exposure, recommendations of the National Committee on Radiation Protection, National Bureau of Standards Handbook 69, (August1963);
22. (22) "Immersion recreation," a beneficial use assigned to surface waters of the state that are suitable for uses where the human body may come in direct contact with the water, to the point of complete submersion, and where water may be accidentally ingested or where certain sensitive organs such as the eyes, ears, and nose may be exposed to water;
23. (23) "Impact," a man-induced change in the chemical, physical, or biological quality or condition of surface waters of the state;
24. (24) "Impairment," a detrimental effect on the aquatic community caused by an impact that prevents attainment of the designated use;
25. (25) "Irrigation," a beneficial use assigned to surface waters of the state that are suitable for irrigating farm lands, ranch lands, gardens, and recreational areas;
26. (26) "Lake," a pond, reservoir, or other body of water, created by either natural or artificial means, but not a pond or appurtenance that is used for the treatment and disposal of wastes and that is permitted for such uses;
27. (27) "Limited-contact recreation," a beneficial use assigned to surface waters of the state that are suitable for boating, fishing, and other water-related recreation, other than immersion recreation, where a person's water contact is limited to the extent that infections of the eyes, ears, respiratory or digestive systems, or urogenital areas are normally avoided;
28. (28) "Metalimnion," the middle layer of a water column, in a thermally stratified waterbody;
29. (29) "µg/L," micrograms per liter, a measure of concentration;
30. (30) "mg/L," milligrams per liter, a measure of concentration;
31. (31) "micromhos/cm," micromhos per centimeter, a measure of electrical conductivity;
32. (32) "Nonpoint source," a source of pollution that is not defined as a point source;
33. (33) "Parameter," a chemical, physical, or biological characteristic that affects the use of surface waters of the state;
34. (34) "pCi/L," picocuries per liter, a measure of radioactive concentration;
35. (35) "Segment," a continuous stretch of water found between two points in the bed of a stream;

36. (36) "Sodium adsorption ratio," a calculated value that evaluates the sodium hazard of irrigation water based on the Gapon equation and expressed by the mathematical expression:

    Sodium Adsorption Ratio =

    where Na⁺, Ca⁺², and Mg⁺² are expressed as milliequivalents per liter;

37. (37) "Spawning bed," a place where fish spawn;
38. (38) "Stream," a river, creek, tributary, or other watercourse;
39. (39) "Surface waters of the state," lakes, ponds, streams, rivers, wetlands, and any other body or accumulation of water on the land surface that is considered to be waters of the state, but not waste treatment systems, including treatment ponds, lagoons, leachate collection ponds, or stormwater retention ponds designed to meet the requirements under § 402 or § 404 of the Federal Water Pollution Control Act as amended to February 4, 1987;
40. (40) "Thermocline," the depth range characterized by a rapid change in temperature with depth, in a thermally stratified waterbody;
41. (41) "Thirty-day average," the arithmetic mean of a minimum of three consecutive grab or composite samples taken on separate weeks in a 30-day period;
42. (42) "Toxic pollutant," a pollutant or combination of pollutants, including disease-causing agents, which, upon exposure, ingestion, inhalation, or assimilation into an organism, either directly from the environment or indirectly by ingestion through food chains, may cause death, disease, behavioral abnormality, cancer, genetic mutation, physiological malfunctions including reproductive malfunction, or physical deformity, in an organism or its offspring;
43. (43) "Warmwater marginal fish life propagation," a beneficial use assigned to surface waters of the state that will support aquatic life and more tolerant species of warmwater fish naturally or by frequent stocking and intensive management but which suffer frequent fish kills because of critical natural conditions;
44. (44) "Warmwater permanent fish life propagation," a beneficial use assigned to surface waters of the state that support aquatic life and are suitable for the permanent propagation or maintenance, or both, of warmwater fish. Stocked coldwater fish may also be present;
45. (45) "Warmwater semipermanent fish life propagation waters," a beneficial use assigned to surface waters of the state that support aquatic life and are suitable for the propagation or maintenance, or both, of warmwater fish, but which may suffer occasional fish kills because of critical natural conditions;
46. (46) "Weekly average temperature," the mathematical mean of multiple, equally spaced daily temperature measurements over a seven-day consecutive period, with a minimum of three data points equally spaced throughout each day;
47. (47) "Wetlands," those areas that are inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions, including swamps, marshes, bogs, and similar areas;
48. (48) "Zone of mixing," an area in a stream where an effluent or discharge mixes with the upstream water.

Source: SL 1975, ch 16, § 1; 4 SDR 32, effective December 4, 1977; 5 SDR 21, effective September 21, 1978; transferred from § 34:04:02:01, effective July 1, 1979; 10 SDR 145, effective July 4, 1984; 13 SDR 129, 13 SDR 141, effective July 1, 1987; 14 SDR 86, effective December 24, 1987; 19 SDR 111, effective January 31, 1993; transferred from § 74:03:02:01, July 1, 1996; 24 SDR 10, effective July 20, 1997; 25 SDR 98, effective January 27, 1999; 31 SDR 29, effective September 13, 2004; 35 SDR 253, effective May 12, 2009; 41 SDR 109, effective January 12, 2015 ; 49 SDR 96, effective May 14, 2023 .

General Authority: SDCL 34A-2-93 .

Law Implemented: SDCL 34A-2- 11 .

Prior versions effective: 2015-01-12, 2009-05-12, 2009-04-12.