Section 445A.1237 - Standards for selenium for support of aquatic life applicable to designated waters1. The standards for selenium prescribed in this section for the support of aquatic life are applicable to the waters specified in NAC 445A.123 to 445A.2234, inclusive. The criterion values for selenium are calculated to reflect the lack of sturgeon or related fish species in the waters of this State and maintain the conditions necessary to support, protect and allow the propagation of fish species found in the waters of this State. See references a and b.2. If the standards for selenium are exceeded at a site, the Commission will review and may adjust the standards for the site if: (a) The standards are not economically controllable; or(b) Site-specific values for fish and water have been derived through a technically defensible study (see references a and b) and results have been approved by the Division.3. If data from fish tissue are available, such data shall take precedence over data obtained from a water sample. If data from fish egg or ovary tissue are available, such data shall take precedence over data from whole body tissue or fish muscle tissue.4. Any sampling of fish tissue must be performed in accordance with EPA protocols. See references a and b.5. Any person or entity wishing to develop site-specific values for fish tissue and water shall submit a proposed sampling and analysis plan to the Division. The plan must be approved by the Division before the study to derive site-specific values for fish tissue and water is conducted.6. Except as provided in subsection 2, the criterion values for selenium in fish tissue are instantaneous values that may not be exceeded. The criterion values for selenium in fish tissue are: Type of Tissue Analyzed | Criterion Value (mg/kg dry weight) |
Fish Egg or Ovary Tissue | 19 |
Fish Whole Body Tissue | 9.5 |
Fish Muscle Tissue | 13.1 |
7. Except as provided in subsection 2, the criterion values for dissolved selenium in the water column for aquatic life is: Exposure Duration and Category of Water | Criterion Value (µg/L) |
30-day average, lentic water | 1.9 |
30-day average, lotic water | 3.9 |
Intermittent, lentic water | 1.9 - Cbkgd(1 - fint)/fint |
Intermittent, lotic water | 3.9 - Cbkgd(1 - fint)/fint |
The 30-day average and intermittent concentration limits for selenium may be exceeded only once every 3 years. See reference a.
8. Nothing in this section authorizes a person to take fish without complying with applicable provisions of law related to fishing in this State.9. As used in this section: (a) "Cbkgd" means the average daily ambient concentration integrated over 30 days.(b) "fint" means the fraction of any 30-day period during which there are elevated concentrations of selenium.(c) "Fish muscle tissue" means tissue collected from a skinless and boneless fillet.(d) "Lentic water" means a standing body of water such as a lake or reservoir.(e) "Lotic water" means a flowing or moving body of water such as a stream or river. References:
a. U.S. Environmental Protection Agency, Pub. No. EPA 822-R-16-006, Aquatic Life Ambient Water Quality Criterion for Selenium - Freshwater, June 2016.b. U.S. Environmental Protection Agency, Pub. No. EPA 820-F-16-007, Technical Support for Fish Tissue Monitoring for Implementation of EPA's 2016 Selenium Criterion (Draft), September 2016.Nev. Admin. Code § 445A.1237
Added to NAC by Environmental Comm'n by R043-19A, eff. 12/30/2019; A by R043-19A, 12/30/2019, eff. 1/1/2023