Current through Register Vol. XLI, No. 50, December 13, 2024
Section 47-2-9 - Establishment Of Safe Concentration ValuesWhen a specific water quality standard has not been established by this rule and there is a discharge or proposed discharge into waters of the State, the use of which has been designated a Category B1, B2, B3 or B4, such discharge may be regulated by the secretary where necessary to protect State waters through establishment of a safe concentration value as follows:
9.1. Establishment of a safe concentration value shall be based upon data obtained from relevant aquatic field studies, standard bioassay test data which exists in substantial available scientific literature, or data obtained from specific tests utilizing one (1) or more representative important species of aquatic life designated on a case-by-case basis by the secretary and conducted in a water environment which is equal to or closely approximates that of the natural quality of the receiving waters.9.2. In those cases where it has been determined that there is insufficient available data to establish a safe concentration value for a pollutant, the safe concentration value shall be determined by applying the appropriate application factor as set forth below to the 96-hour LC 50 value. Except where the secretary determines, based upon substantial available scientific data, that an alternate application factor exists for a pollutant, the following appropriate application factors shall be used in the determination of safe concentration values: 9.2.a. Concentrations of pollutants or combinations of pollutants that are not persistent and not cumulative shall not exceed 0.10 (1/10) of the 96-hour LC 50.9.2.b. Concentrations of pollutants or combinations of pollutants that are persistent or cumulative shall not exceed 0.01 (1/100) of the 96-hour LC 50.9.3. Persons seeking issuance of a permit pursuant to this rule authorizing the discharge of a pollutant for which a safe concentration value is to be established using special bioassay tests pursuant to subsection 9.1 shall perform such testing as approved by the secretary and shall submit all of the following in writing to the secretary: 9.3.a. A plan proposing the bioassay testing to be performed.9.3.b. Such periodic progress reports of the testing as may be required by the secretary.9.3.c. A report of the completed results of such testing including, but not limited to, all data obtained during the course of testing and all calculations made in the recording, collection, interpretation, and evaluation of such data.9.4. Bioassay testing shall be conducted in accordance with test procedures outlined in 40 C.F.R. § 136, as amended, or other methodologies approved by the secretary.