Federal regulations · Through 2026-08-25 · Newer source version available

40 CFR 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.
(3) The demonstration required under subparagraph (g)(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 subparagraph (g)(2) of this section, the actions described in paragraph (g)(4), of this section shall be taken, and the demonstration required under paragraph (g)(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 subparagraph (g)(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:
(i) Performs a subsequent analysis which demonstrates that the concentrations of the foregoing nitrosamine compounds do not exceed the levels specified in paragraph (g)(2) of this section; or
(ii) Substitutes a new tube reducing lubricant and thereafter complies with the requirements of paragraph (g)(3) of this section; or
(iii) Determines the source of the pollutant whose concentration exceeded the level specified in paragraph (g)(2) of this section and demonstrates to the satisfaction of the NPDES issuing authority that such source has been eliminated.
(5) The concentration limits specified in paragraph (g)(2) of this section apply at the point of discharge from the tube reducing process. However, sampling after the tube reducing wastewater has been commingled with other wastewaters is permitted if:
(i) Any dilution caused by the other wastewaters is taken into account in determining the appropriate (i.e., lower) allowable discharge concentration; and
(ii) An analytical method of sufficient sensitivity is used to measure the levels of each of the foregoing nitrosamine compounds in the wastewaters being sampled.
(h) Surface treatment spent baths.
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 surface treated
Chromium 0.150 0.61
Cyanide 0.099 0.041
Nickel 0.653 0.432
Ammonia 45.3 20
Fluoride 20.3 8.98
Oil and grease 6.80 4.08
TSS 14 6.63
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.
(i) Surface treatment rinse.
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 zirkonium-hafnium surface treated
Chromium 3.91 1.60
Cyanide 2.58 1.07
Nickel 17.1 11.3
Ammonia 1,190 521
Fluoride 529 235
Oil and grease 178 107
TSS 364 173
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.
(j) Alkaline cleaning spent baths.
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 alkaline cleaned
Chromium 0.704 0.288
Cyanide 0.464 0.192
Nickel 3.07 2.03
Ammonia 214 93.8
Fluoride 95.2 42.3
Oil and grease 32 19.2
TSS 65.6 31.2
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.
(k) Alkaline cleaning rinse.
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 alkaline cleaned
Chromium 13.8 5.65
Cyanide 9.11 3.77
Nickel 60.3 39.9
Ammonia 4,190 1,840
Fluoride 1,870 829
Oil and grease 628 377
TSS 1,290 613
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.
(l) Sawing or grinding spent emulsions.
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 sawed or ground with emulsions
Chromium 0.124 0.051
Cyanide 0.082 0.034
Nickel 0.540 0.357
Ammonia 37.5 16.5
Fluoride 16.7 7.42
Oil and grease 5.62 3.37
TSS 11.5 5.48
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.
(m) Wet air pollution control scrubber blowdown—subpart I—BPT. There shall be no allowance for the discharge of process wastewater pollutants.
(n) Degreasing spent solvents—subpart I—BPT. There shall be no discharge of process wastewater pollutants.
(o) Degreasing rinse—subpart I—BPT. There shall be no discharge or process wastewater pollutants.
(p) Molten salt rinse.
Subpart I—BPT
Pollutant or pollutant property Maximum for any 1 day Maximum for monthy average
mg/off-kg (pounds per million off pounds) of zirconium-hafnium treated with molten salt
Chromium 3.33 1.360
Cyanide 2.20 0.907
Nickel 14.5 9.60
Ammonia 1,010 443
Fluoride 450 200
Oil and grease 151 90.7
TSS 310 148
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.
(q) Sawing or grinding 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 sawed or ground with contact cooling water
Chromium 0.142 0.058
Cyanide 0.093 0.039
Nickel 0.617 0.408
Ammonia 42.8 18.8
Fluoride 19.1 8.48
Oil and grease 6.42 3.85
TSS 13.2 6.26
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.
(r) Sawing on grinding rinse.
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 sawed or ground zirconium hafnium rinsed
Chromium 0.792 0.324
Cyanide 0.522 0.216
Nickel 3.46 2.29
Ammonia 240 106
Fluoride 107 47.5
Oil and grease 36 21.6
TSS 73.8 35.1
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.
(s) Sawing or grinding spent neat oils—subpart I—BPT. There shall be no discharge of process wastewater pollutants.
(t) Inspection and testing wastewater.
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 tested
Chromium 0.007 0.003
Cyanide 0.005 0.002
Nickel 0.030 0.020
Ammonia 2.06 0.903
Fluoride 0.917 0.407
Oil and grease 0.308 0.185
TSS 0.632 0.301
pH (1) (1)
1 Within the range of 7.05 to 10.0 at all times.

Where this section sits in the code

Title 40—Protection of Environment
CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY
SUBCHAPTER N—EFFLUENT GUIDELINES AND STANDARDS
PART 471—NONFERROUS METALS FORMING AND METAL POWDERS POINT SOURCE CATEGORY
Subpart I—Zirconium-Hafnium Forming Subcategory

(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.

(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.

(3) The demonstration required under subparagraph (g)(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 subparagraph (g)(2) of this section, the actions described in paragraph (g)(4), of this section shall be taken, and the demonstration required under paragraph (g)(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 subparagraph (g)(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:

(i) Performs a subsequent analysis which demonstrates that the concentrations of the foregoing nitrosamine compounds do not exceed the levels specified in paragraph (g)(2) of this section; or

(ii) Substitutes a new tube reducing lubricant and thereafter complies with the requirements of paragraph (g)(3) of this section; or

(iii) Determines the source of the pollutant whose concentration exceeded the level specified in paragraph (g)(2) of this section and demonstrates to the satisfaction of the NPDES issuing authority that such source has been eliminated.

(5) The concentration limits specified in paragraph (g)(2) of this section apply at the point of discharge from the tube reducing process. However, sampling after the tube reducing wastewater has been commingled with other wastewaters is permitted if:

(i) Any dilution caused by the other wastewaters is taken into account in determining the appropriate (i.e., lower) allowable discharge concentration; and

(ii) An analytical method of sufficient sensitivity is used to measure the levels of each of the foregoing nitrosamine compounds in the wastewaters being sampled.

(h) Surface treatment spent baths.

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 surface treated

Chromium 0.150 0.61

Cyanide 0.099 0.041

Nickel 0.653 0.432

Ammonia 45.3 20

Fluoride 20.3 8.98

Oil and grease 6.80 4.08

TSS 14 6.63

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.

(i) Surface treatment rinse.

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 zirkonium-hafnium surface treated

Chromium 3.91 1.60

Cyanide 2.58 1.07

Nickel 17.1 11.3

Ammonia 1,190 521

Fluoride 529 235

Oil and grease 178 107

TSS 364 173

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.

(j) Alkaline cleaning spent baths.

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 alkaline cleaned

Chromium 0.704 0.288

Cyanide 0.464 0.192

Nickel 3.07 2.03

Ammonia 214 93.8

Fluoride 95.2 42.3

Oil and grease 32 19.2

TSS 65.6 31.2

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.

(k) Alkaline cleaning rinse.

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 alkaline cleaned

Chromium 13.8 5.65

Cyanide 9.11 3.77

Nickel 60.3 39.9

Ammonia 4,190 1,840

Fluoride 1,870 829

Oil and grease 628 377

TSS 1,290 613

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.

(l) Sawing or grinding spent emulsions.

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 sawed or ground with emulsions

Chromium 0.124 0.051

Cyanide 0.082 0.034

Nickel 0.540 0.357

Ammonia 37.5 16.5

Fluoride 16.7 7.42

Oil and grease 5.62 3.37

TSS 11.5 5.48

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.

(m) Wet air pollution control scrubber blowdown—subpart I—BPT. There shall be no allowance for the discharge of process wastewater pollutants.

(n) Degreasing spent solvents—subpart I—BPT. There shall be no discharge of process wastewater pollutants.

(o) Degreasing rinse—subpart I—BPT. There shall be no discharge or process wastewater pollutants.

(p) Molten salt rinse.

Subpart I—BPT

Pollutant or pollutant property Maximum for any 1 day Maximum for monthy average

mg/off-kg (pounds per million off pounds) of zirconium-hafnium treated with molten salt

Chromium 3.33 1.360

Cyanide 2.20 0.907

Nickel 14.5 9.60

Ammonia 1,010 443

Fluoride 450 200

Oil and grease 151 90.7

TSS 310 148

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.

(q) Sawing or grinding 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 sawed or ground with contact cooling water

Chromium 0.142 0.058

Cyanide 0.093 0.039

Nickel 0.617 0.408

Ammonia 42.8 18.8

Fluoride 19.1 8.48

Oil and grease 6.42 3.85

TSS 13.2 6.26

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.

(r) Sawing on grinding rinse.

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 sawed or ground zirconium hafnium rinsed

Chromium 0.792 0.324

Cyanide 0.522 0.216

Nickel 3.46 2.29

Ammonia 240 106

Fluoride 107 47.5

Oil and grease 36 21.6

TSS 73.8 35.1

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.

(s) Sawing or grinding spent neat oils—subpart I—BPT. There shall be no discharge of process wastewater pollutants.

(t) Inspection and testing wastewater.

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 tested

Chromium 0.007 0.003

Cyanide 0.005 0.002

Nickel 0.030 0.020

Ammonia 2.06 0.903

Fluoride 0.917 0.407

Oil and grease 0.308 0.185

TSS 0.632 0.301

pH (1) (1)

1 Within the range of 7.05 to 10.0 at all times.

Collected 2026-08-27T02:26:04Z. Source file · JSON

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