§ 471.31 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 125.30-125.32, any existing point source sub-
ject 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 C—BPT. There shall be no discharge of process wastewater pollutants.
(b) Rolling spent emulsions.
Subpart C—BPT
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/off-kg (pounds per million off-pounds) of nickel-cobalt rolled with emulsions | ||
| Chromium | 0.075 | 0.031 |
| Nickel | 0.327 | 0.216 |
| Fluoride | 10.1 | 4.49 |
| Oil and grease | 3.4 | 2.04 |
| TSS | 6.97 | 3.32 |
| pH | ( 1) | ( 1) |
1 Within the range of 7.5 to 10.0 at all times.
(c) Rolling contact cooling water.
Subpart C—BPT
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/off-kg (pounds per million off-pounds) of nickel-cobalt rolled with water | ||
| Chromium | 1.66 | 0.679 |
| Nickel | 7.24 | 4.79 |
| Fluoride | 225 | 99.6 |
| Oil and grease | 75.4 | 45.3 |
| TSS | 155 | 73.5 |
| pH | ( 1) | ( 1) |
1 Within the range of 7.5 to 10.0 at all times.
(d) Tube Reducing Spent Lubricant—subpart C—BPT. (1) There shall be no discharge of process wastewater pollutants except as provided under paragraph (d)(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.
(3) The demonstration required under paragraph (d)(2) of this section shall be made once per month until the demonstration has been made for all three nitrosamine compounds for six consecutive months, after which time the demonstration may be made once per quarter. If a sample is found to contain any of the foregoing nitrosamine compounds at concentrations greater than those specified in paragraph (d)(2) of this section, the actions described in paragraph (d)(4) of this section shall be taken, and the demonstration required under paragraph (d)(2) of this section shall be made once per month until it has been made for all three nitrosamine compounds for six consecutive months.
(4) If sampling results show that any of the foregoing nitrosamine compounds is present in the process wastewater at concentrations greater than those specified in paragraph (d)(2) of this section, the facility owner or operator shall ensure that, within thirty days of receiving written notification of the sampling results, there is no further discharge of tube reducing spent lubricant wastewater until the owner or operator: