Definitions

Definitions. Definitions. In this chapter the following definitions apply: (1) “Biological assessment threshold” has the meaning defined in s. NR 102.03 (1e) . (2) “Clean Water Act” or “CWA” means the federal Clean Water Act of 1972 and amendments. (3) “Designated use” means a use assigned to Wisconsin’s waterbodies as specified in s. NR 102.04 . (4) “Less stringent SSC” means a site-specific phosphorus criterion that is established at a concentration higher than a waterbody’s statewide phosphorus criterion. (5) “More stringent SSC” means a site-specific phosphorus criterion that is established at a concentration lower than a waterbody’s statewide phosphorus criterion. (6) “Natural background phosphorus concentration” means the phosphorus concentration from natural sources, including forested and undeveloped lands, and from natural processes such as weathering and dissolution, that would exist in the absence of measurable impacts from human activity or influence. (7) “Phosphorus response indicator” means an indicator and its thresholds, as specified in s. NR 102.60 (2) to (4) , that characterize the condition or abundance of aquatic organisms that are responsive to phosphorus. (8) “Section 303(d) list” means a list of waters that do not attain water quality standards and require a total maximum daily load analysis, as specified in Section 303(d) of the Clean Water Act. (9) “Site-specific criterion” or “SSC” means a phosphorus criterion applicable to a waterbody or segment that differs from the statewide phosphorus criterion due to specific conditions at the waterbody or segment, documented using data for the specific site or a similar reference site. (10) “Statewide phosphorus criterion” means the statewide phosphorus surface water quality criterion specified in s. NR 102.06 that applies to a specific waterbody in absence of an adopted, approved, and effective site-specific criterion. (11) “Strahler stream order” is a numerical hierarchy of stream segments increasing from headwaters through downstream reaches. (12) “Total maximum daily load” or “TMDL” has the meaning defined in s. NR 212.72 (11) . (13) “U.S. EPA” means the United States environmental protection agency. (14) “Weather-controlled total phosphorus concentration” has the meaning defined in s. NR 102.07 (1) (c) 1. (15) “WPDES permit” means a Wisconsin pollutant discharge elimination system permit issued by the department under ch. 283 , Stats.