40 C.F.R. § 131.35
(d)
Definitions.
(1)
Acute toxicity means a deleterious response (e.g., mortality, disorientation, immobilization) to a stimulus observed in 96 hours or less.
(2)
Background conditions means the biological, chemical, and physical conditions of a water body, upstream from the point or non-point source discharge under consideration. Background sampling location in an enforcement action will be upstream from the point of discharge, but not upstream from other inflows. If several discharges to any water body exist, and an enforcement action is being taken for possible violations to the standards, background sampling will be undertaken immediately upstream from each discharge.
(3)
Ceremonial and Religious water use means activities involving traditional Native American spiritual practices which involve, among other things, primary (direct) contact with water.
(4)
Chronic toxicity means the lowest concentration of a constituent causing observable effects (i.e., considering lethality, growth, reduced reproduction, etc.) over a relatively long period of time, usually a 28-day test period for small fish test species.
(5)
Council— or Tribal Council means the Colville Business Council of the Colville Confederated Tribes.
(6)
Geometric mean means the nth root of a product of n factors.
(7)
Mean retention time means the time obtained by dividing a reservoir's mean annual minimum total storage by the non-zero 30-day, ten-year low-flow from the reservoir.
(8)
Mixing zone— or dilution zone means a limited area or volume of water where initial dilution of a discharge takes place; and where numeric water quality criteria can be exceeded but acutely toxic conditions are prevented from occurring.
(9)
pH means the negative logarithm of the hydrogen ion concentration.
(10)
Primary contact recreation means activities where a person would have direct contact with water to the point of complete submergence, including but not limited to skin diving, swimming, and water skiing.
(11)
Regional Administrator means the Administrator of EPA's Region X.
(12)
Reservation means all land within the limits of the Colville Indian Reservation, established on July 2, 1872 by Executive Order, presently containing 1,389,000 acres more or less, and under the jurisdiction of the United States government, notwithstanding the issuance of any patent, and including rights-of-way running through the reservation.
(13)
Secondary contact recreation means activities where a person's water contact would be limited to the extent that bacterial infections of eyes, ears, respiratory, or digestive systems or urogenital areas would normally be avoided (such as wading or fishing).
(14)
Surface water means all water above the surface of the ground within the exterior boundaries of the Colville Indian Reservation including but not limited to lakes, ponds, reservoirs, artificial impoundments, streams, rivers, springs, seeps and wetlands.
(15)
Temperature means water temperature expressed in Centigrade degrees (C).
(16)
Total dissolved solids—
(TDS)
means the total filterable residue that passes through a standard glass fiber filter disk and remains after evaporation and drying to a constant weight at 180 degrees C. it is considered to be a measure of the dissolved salt content of the water.
(17)
Toxicity means acute and/or chronic toxicity.
(18)
Tribe— or Tribes means the Colville Confederated Tribes.
(19)
Turbidity means the clarity of water expressed as nephelometric turbidity units (NTU) and measured with a calibrated turbidimeter.
(20)
Wildlife habitat means the waters and surrounding land areas of the Reservation used by fish, other aquatic life and wildlife at any stage of their life history or activity.
(e)
General considerations. The following general guidelines shall apply to the water quality standards and classifications set forth in the use designation Sections.
(1)
Classification boundaries. At the boundary between waters of different classifications, the water quality standards for the higher classification shall prevail.
(2)
Antidegradation policy. This antidegradation policy shall be applicable to all surface waters of the Reservation.
(i)
Existing in-stream water uses and the level of water quality necessary to protect the existing uses shall be maintained and protected.
(ii)
Where the quality of the waters exceeds levels necessary to support propagation of fish, shellfish, and wildlife and recreation in and on the water, that quality shall be maintained and protected unless the Regional Administrator finds, after full satisfaction of the inter-governmental coordination and public participation provisions of the Tribes' continuing planning process, that allowing lower water quality is necessary to accommodate important economic or social development in the area in which the waters are located. In allowing such degradation or lower water quality, the Regional Administrator shall assure water quality adequate to protect existing uses fully. Further, the Regional Administrator shall assure that there shall be achieved the highest statutory and regulatory requirements for all new and existing point sources and all cost-effective and reasonable best management practices for nonpoint source control.
(iii)
Where high quality waters are identified as constituting an outstanding national or reservation resource, such as waters within areas designated as unique water quality management areas and waters otherwise of exceptional recreational or ecological significance, and are designated as special resource waters, that water quality shall be maintained and protected.
(iv)
In those cases where potential water quality impairment associated with a thermal discharge is involved, this antidegradation policy's implementing method shall be consistent with
section 316 of the Clean Water Act.
(3)
Aesthetic qualities. All waters within the Reservation, including those within mixing zones, shall be free from substances, attributable to wastewater discharges or other pollutant sources, that:
(i)
Settle to form objectionable deposits;
(ii)
Float as debris, scum, oil, or other matter forming nuisances;
(iii)
Produce objectionable color, odor, taste, or turbidity;
(iv)
Cause injury to, are toxic to, or produce adverse physiological responses in humans, animals, or plants; or
(v)
produce undesirable or nuisance aquatic life.
(4)
Analytical methods.
(i)
The analytical testing methods used to measure or otherwise evaluate compliance with water quality standards shall to the extent practicable, be in accordance with the “Guidelines Establishing Test Procedures for the Analysis of Pollutants” (
40 CFR part 136). When a testing method is not available for a particular substance, the most recent edition of “Standard Methods for the Examination of Water and Wastewater” (published by the American Public Health Association, American Water Works Association, and the Water Pollution Control Federation) and other or superseding methods published and/or approved by EPA shall be used.
(g)
General classifications. General classifications applying to various surface waterbodies not specifically classified under
§ 131.35(h) are as follows:
(1)
All surface waters that are tributaries to Class I waters are classified Class I, unless otherwise classified.
(2)
Except for those specifically classified otherwise, all lakes with existing average concentrations less than 2000 mg/L TDS and their feeder streams on the Colville Indian Reservation are classified as Lake Class and Class I, respectively.
(3)
All lakes on the Colville Indian Reservation with existing average concentrations of TDS equal to or exceeding 2000 mg/L and their feeder streams are classified as Lake Class and Class I respectively unless specifically classified otherwise.
(4)
All reservoirs with a mean detention time of greater than 15 days are classified Lake Class.
(5)
All reservoirs with a mean detention time of 15 days or less are classified the same as the river section in which they are located.
(6)
All reservoirs established on pre-existing lakes are classified as Lake Class.
(7)
All wetlands are assigned to the Special Resource Water Class.
(8)
All other waters not specifically assigned to a classification of the reservation are classified as Class II.
Notes, amendments, and revision history
Amendments
[54 FR 28625, July 6, 1989]
Authority
Authority: 33 U.S.C. 1251 et seq.
Source
Source: 48 FR 51405, Nov. 8, 1983, unless otherwise noted.
Amendments
[54 FR 28625, July 6, 1989]