[Code of Federal Regulations]
[Title 40, Volume 26]
[Revised as of July 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR421.12]

[Page 462]
 
                TITLE 40-PROTECTION OF ENVIRONMENT
 
      CHAPTER I-ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 421-NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY--Table of Contents
 
              Subpart A-Bauxite Refining Subcategory
 
Sec. 421.12  Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control 
          technology currently available.

    Except as provided in 40 CFR 125.30 through 125.32, any existing 
point source subject to this subpart, shall achieve the following 
effluent limitations representing the degree of effluent reduction 
attainable by the application of the best practicable control technology 
currently available:
    (a) Subject to the provisions of paragraph (b) of this section, the 
following limitations establish the quantity or quality of pollutants or 
pollutant properties which may be discharged by a point source subject 
to the provisions of this subpart after application of the best 
practicable control technology currently available: There shall be no 
discharge of process waste water pollutants to navigable waters.
    (b) During any calendar month there may be discharged from the 
overflow of a process waste water impoundment either a volume of process 
waste water equal to the difference between the precipitation for that 
month that falls within the impoundment and the evaporation within the 
impoundment for that month, or, if greater, a volume of process waste 
water equal to the difference between the mean precipitation for that 
month that falls within the impoundment and the mean evaporation for 
that month as established by the National Climatic Center, National 
Oceanic and Atmospheric Administration, for the area in which such 
impoundment is located (or as otherwise determined if no monthly data 
have been established by the National Climatic Center).

[39 FR 12825, Apr. 8, 1974, as amended at 50 FR 38342, Sept. 20, 1985]