(a) Except as provided in 40 CFR 125.30 through 125.32, any existing point source subject to this subpart must achieve the following effluent limitations representing the degree of effluent reduction attainable by the application of the best available technology economically achievable:
(b) There shall be no discharge allowance for wastewater pollutants from the degassing operation.
(c) The discharge of wastewater pollutants from the core and ancillary operation except those in (b) of this section, shall not exceed the values set forth below:
Subpart C
Core ------------------------------------------------------------------------
BAT effluent limitations
---------------------------
Pollutant or pollutant property Maximum for
Maximum for monthly
any 1 day average------------------------------------------------------------------------
mg/off-kg (lb/million off-
lbs) of aluminum extruded
---------------------------Chromium.................................... 0.15 0.061Cyanide..................................... 0.098 0.041Zinc........................................ 0.49 0.21Aluminum.................................... 2.19 1.09------------------------------------------------------------------------
Subpart C
Extrusion Press Leakage ------------------------------------------------------------------------
BAT effluent limitations
---------------------------
Pollutant or pollutant property Maximum for
Maximum for monthly
any 1 day average------------------------------------------------------------------------
mg/off-kg (lb/million off-
lbs) of aluminum extruded
---------------------------Chromium.................................... 0.65 0.27Cyanide..................................... 0.43 0.18Zinc........................................ 2.16 0.90Aluminum.................................... 9.51 4.73------------------------------------------------------------------------
Subpart C
Direct Chill Casting Contact Cooling Water ------------------------------------------------------------------------
BAT effluent limitations
---------------------------
Pollutant or pollutant property Maximum for
Maximum for monthly
any 1 day average------------------------------------------------------------------------
mg/off-kg (lb/million off-
lbs) of aluminum cast
---------------------------Chromium.................................... 0.59 0.24Cyanide..................................... 0.39 0.16Zinc........................................ 1.94 0.81Aluminum.................................... 8.55 4.26------------------------------------------------------------------------
Subpart C
Press Heat Treatment Contact Cooling Water ------------------------------------------------------------------------
BAT effluent limitations
---------------------------
Pollutant or pollutant property Maximum for
Maximum for monthly
any 1 day average------------------------------------------------------------------------
mg/off-kg (lb/million off-
lbs) of aluminum quenched
---------------------------Chromium.................................... 0.90 0.37Cyanide..................................... 0.59 0.25Zinc........................................ 2.98 1.25Aluminum.................................... 13.10 6.52------------------------------------------------------------------------
Subpart C
Solution Heat Treatment Contact Cooling Water ------------------------------------------------------------------------
BAT effluent limitations
-------------------------
Pollutant or pollutant property Maximum for
Maximum for monthly
any 1 day average------------------------------------------------------------------------
mg/off-kg (lb/million
off-lbs) of aluminum
quenched
-------------------------Chromium...................................... 0.90 0.37Cyanide....................................... 0.59 0.25Zinc.......................................... 2.98 1.25Aluminum...................................... 13.10 6.52------------------------------------------------------------------------
Subpart C
Cleaning or Etching Bath ------------------------------------------------------------------------
BAT effluent limitations
---------------------------
Pollutant or pollutant property Maximum for
Maximum for monthly
any 1 day average------------------------------------------------------------------------
mg/off-kg (lb/million off-
lbs) of aluminum cleaned
or etched
---------------------------Chromium.................................... 0.079 0.032Cyanide..................................... 0.052 0.022Zinc........................................ 0.262 0.109Aluminum.................................... 1.15 0.58------------------------------------------------------------------------
Subpart C
Cleaning or Etching Rinse ------------------------------------------------------------------------
BAT effluent limitations
-------------------------
Pollutant or pollutant property Maximum for
Maximum for monthly
any 1 day average------------------------------------------------------------------------
mg/off-kg (lb/million
off-lbs) of aluminum
cleaned or etched
-------------------------Chromium...................................... 1.7 0.7Cyanide....................................... 1.2 0.5Zinc.......................................... 5.7 2.4Aluminum...................................... 25 13------------------------------------------------------------------------
Subpart C
Cleaning or Etching Scrubber Liquor ------------------------------------------------------------------------
BAT effluent limitations
-------------------------
Pollutant or pollutant property Maximum for
Maximum for monthly
any 1 day average------------------------------------------------------------------------
mg/off-kg (lb/million
off-lbs) of aluminum
cleaned or etched
-------------------------Chromium...................................... 0.85 0.35Cyanide....................................... 0.56 0.23Zinc.......................................... 2.82 1.18Aluminum...................................... 12.43 6.19------------------------------------------------------------------------ [48 FR 49149, Oct. 24, 1983; 49 FR 11631, 11633, and 11634, Mar. 27, 1984, as amended at 53 FR 52370, Dec. 27, 1988]