§ 471.91 Effluent limitations representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available (BPT).
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 for the process operations representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available (BPT):
(a) Rolling spent neat oils—subpart I—BPT. There shall be no discharge of process wastewater pollutants.
(b) Drawing spent lubricants—subpart I—BPT. There shall be no discharge of process wastewater pollutants.
(c) Extrusion spend emulsions—subpart I—BPT. There shall be no discharge of process wastewater pollutants.
(d) Extrusion press hydraulic fluid leakage.
Subpart I—BPT
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/off-kg (pounds per million off-pounds) of zirconium-hafnium extruded | ||
| Chromium | 0.104 | 0.043 |
| Cyanide | 0.069 | 0.029 |
| Nickel | 0.455 | 0.301 |
| Ammonia | 31.6 | 13.9 |
| Fluoride | 14.1 | 6.26 |
| Oil and grease | 4.74 | 2.85 |
| TSS | 9.72 | 4.62 |
| pH | ( 1) | ( 1) |
1 Within the range of 7.5 to 10.0 at all times.
(e) Swaging spent neat oils—subpart I—BPT. There shall be no discharge of process wastewater pollutants.
(f) Heat treatment contact cooling water.
Subpart I—BPT
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/off-kg (pounds per million off-pounds) of zirconium-hafnium heat treated | ||
| Chromium | 0.151 | 0.062 |
| Cyanide | 0.100 | 0.041 |
| Nickel | 0.659 | 0.436 |
| Ammonia | 45.7 | 20.1 |
| Fluoride | 20.4 | 9.06 |
| Oil and grease | 6.86 | 4.12 |
| TSS | 14.1 | 6.69 |
| pH | ( 1) | ( 1) |
1 Within the range of 7.5 to 10.0 at all times.
(g) Tube Reducing Spent Lubricant—subpart I—BPT. (1) There shall be no discharge of process wastewater pollutants except as provided under paragraph (g)(2) of this section.
(2) Process wastewater pollutants may be discharged, with no allowance for any pollutants discharged, provided the facility owner or operator demonstrates, on the basis of analytical methods set forth in or approved pursuant to 40 CFR part 136, that the concentrations of nitrosamine compounds in the wastewater discharged from the tube reducing process do not exceed 0.050 mg/l of N-nitrosodimethylamine, 0.020 mg/l of N-nitrosodiphenylamine, and 0.020 mg/l of N-nitrosodi-n-propylamine.