Mo. Code Regs. tit. 10 § 20-7.050
Current through Register Vol. 49, No. 24, December 16, 2024
Section 10 CSR 20-7.050 - Methodology for Development of Impaired Waters ListPURPOSE: This rule describes the process used to develop the list of impaired waters as required by the Federal Water Pollution Control Act, Section 303(d), for the purpose of identifying those waters that do not fulfill their designated uses and require the development of total maximum daily loads.
(1) Definitions.(A) Aquatic assemblage-Any major group of aquatic organisms, such as fish, aquatic macroinvertebrate animals, algae, or aquatic macrophytes. (B) Pollutant-Dredged spoil, solid waste, incinerator residue, sewage, garbage, sewer sludge, munitions, chemical waste, biological materials, radioactive materials, heat, wrecked or discarded equipment, rock, sand, cellar dirt, filter backwash, or industrial, municipal, or agricultural waste discharged into water. (C) Qualitative biological monitoring- Monitoring that identifies the different taxa but not the relative abundance of the organisms being sampled. (D) Quantitative biological monitoring- Monitoring that determines the density per unit area or relative abundance of living organisms. (E) Section 303(d) list-A list of certain impaired waters, required by Section 303(d) of the Federal Water Pollution Control Act. (F) Total maximum daily load (TMDL) studies. The objective of these studies is to determine the allowable amounts of a Section 303(d) listed pollutant that can be discharged to a Section 303(d) listed water and still be protective of all applicable water quality standards. (2) Acceptable Water Quality Data for Use in Compiling the 303(d) List. (A) The Missouri Department of Natural Resources (the department) will receive and review all data submitted, and will use scientifically defensible data. Scientifically defensible data will include data meeting the following requirements: 1. All environmental data generated directly by the department or through contracts funded by the department or the United States Environmental Protection Agency (USEPA) that are governed by a Quality Assurance Project Plan (QAPP) as required by the Total Quality Management Plan completed by the department and USEPA. The organization responsible for collection or collection and analysis of the environmental sampling must write and adhere to a QAPP approved by the quality assurance manager of the department; or 2. All environmental data collected by any other agencies, organizations, or individuals that are governed by an internal quality assurance program that has been reviewed and approved by the department. (B) Only data collected subsequent to events with potential to cause permanent change in water quality in a given water shall be used to assess the present condition of that water. (C) The department shall recognize four (4) levels of assurance for water quality data. Only data of Level 2 or higher shall be used to support additions, deletions, or changes to the proposed 303(d) list, unless the problem can be accurately characterized by Level 1 data. These four (4) levels are: 1. Level 1: All data not constituting Levels 2, 3, or 4. 2. Level 2: A. Chemical data, collected quarterly to bimonthly for at least three (3) years, or intensive studies that monitor several nearby sites repeatedly over short periods of time; or B. At least three (3) fish tissue samples. 3. Level 3: A. Chemical data collected at least monthly for more than three (3) years and providing data on a variety of water quality constituents, including heavy metals and pesticides; or B. Quantitative biological monitoring of at least one (1) aquatic assemblage at multiple sites. 4. Level 4: A. Chemical data collected at least monthly for more than three (3) years and providing data on a variety of water quality constituents, including heavy metals and pesticides, and including chemical sampling of sediments and fish tissue; or B. Quantitative biological monitoring of at least two (2) aquatic assemblages at multiple sites. (3) How Water Quality Data is Evaluated for the Development of the 303(d) List. (A) The department shall evaluate physical, chemical, biological, and toxicological data and determine whether any designated beneficial uses of waters are not being fully met. If any designated beneficial uses of a water are determined to not be fully met, that water will be considered impaired. (B) The following means may also be used to determine whether waters are impaired. This list is not all-inclusive. 1. Missouri's narrative water quality criteria as described in 10 CSR 20-7.031, section (3) may be used to evaluate waters when a quantitative value can be applied to the pollutant. 2. The analysis of aquatic invertebrate data may be supported by habitat assessment protocols. 3. The department shall review the proposed 303(d) lists of all states with which Missouri shares border waters (Des Moines River, Mississippi River, Missouri River, and St. Francis River). When another state lists one of those waters differently than it is listed by Missouri, the department will request the data justifying that listing in the other state. Those data will be reviewed according to established data evaluation guidelines, and Missouri's listing of that water may be changed, according to the result of that evaluation. In the case of a water that crosses into or out of Missouri, if that water's proposed 303(d) listing status changes at the state line, the department shall, upon the request of the bordering state, EPA, or another interested party, review and evaluate the data justifying that water's listing in the other state. The review will take place according to established data evaluation guidelines, and Missouri's listing of that water may be changed, according to the result of that evaluation.(4) Creation of the Proposed 303(d) List. (A) The department shall develop a detailed methodology for identifying waters that are impaired and shall submit the methodology to public review prior to the development of an impaired waters list. The methodology shall include an explanation of how data are used, how the data are evaluated to determine impairment, and how a list of impaired waters is developed. The development of the methodology shall involve at least one (1) stakeholder meeting inviting all persons expressing an interest in the methodology and a sixty (60)-day comment period on the final draft. Following the review of public comments on the draft methodology, the department will provide written responses to the comments and obtain approval of the methodology from the Missouri Clean Water Commission before beginning water quality assessments for the purpose of completing the 303(d) list. (B) The 303(d) list shall be developed in accordance with section 644.036.5, RSMo. (C) The department shall establish priority ratings or schedules for the creation of total maximum daily loads (TMDLs) for waters on the proposed 303(d) list in accordance with the Federal Water Pollution Control Act, Section 303(d). AUTHORITY: section 644.026, RSMo 2000.* Original rule filed Nov. 5, 2003, effective 7/30/2004. Emergency amendment filed Oct. 16, 2006, effective 10/26/2006, expired 4/23/2007. Amended: Filed Nov. 14, 2006, effective 8/30/2007. Emergency amendment filed Sept. 15, 2008, effective 1/2/2009, expired 6/30/2009. Amended: Filed Sept. 15, 2008, effective 6/30/2009.*Original authority: 644.026, RSMo 1972, amended 1973, 1987, 1993, 1995, 2000.