40 C.F.R. § 471.91

Current through October 31, 2024

Section 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.

40 C.F.R. §471.91

50 FR 34270, Aug. 23, 1985; 51 FR 2888, Jan. 22, 1986, as amended at 54 FR 11350, Mar. 17, 1989