Regulations last checked for updates: Oct 18, 2024

Title 40 - Protection of Environment last revised: Oct 16, 2024
§ 421.210 - Applicability: Description of the primary molybdenum and rhenium subcategory.

The provisions of this subpart are applicable to discharges resulting from the production of molybdenum and rhenium facilities.

§ 421.211 - Specialized definitions.

For the purpose of this subpart the general definitions, abbreviations, and methods of analysis set forth in 40 CFR part 401 shall apply to this subpart.

§ 421.212 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available.

Except as provided in 40 CFR 125.30 through 125.32, any existing point source subject to this subpart shall achieve the following effluent limitation representing the degree of effluent reduction attainable by the application of the best practicable technology currently available:

(a) Molybdenum sulfide leachate.

BPT Limitations for the Primary Molybdenum Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum monthly average
mg/kg (pounds per million pounds) of molybdenum sulfide leached
Arsenic0.9680.431
Lead0.1950.093
Nickle0.8890.588
Selenium0.5700.255
Molybdenum[Reserved][Reserved].
Ammonia (as N)61.72027.130
Fluoride16.2109.214
Total suspended solids18.9809.029
pH( 1)( 1)

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

(b) Roaster SO2 scrubber.

BPT Limitations for the Primary Molybdenum and Rhenium Subcategory

Pollutant of pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of molybdenum sulfide roasted
Arsenic3.5091.561
Lead0.7050.336
Nickel3.2242.133
Selenium2.0650.924
Molybdenum[Reserved][Reserved].
Ammonia (as N)223.80098.390
Fluoride58.77033.410
Total suspended solids68.84032.740
pH( 1)( 1)

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

(c) Molybdic oxide leachate.

BPT Limitations for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of molybdenum contained in molybdic oxide leached
Arsenic24.21010.770
Lead4.8652.317
Nickel22.24014.710
Selenium14.2506.371
Molybdenum[Reserved][Reserved]
Ammonia (as N)1,544.000678.800
Fluoride405.400230.500
Total suspended solids474.900225.900
pH( 1)( 1)

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

(d) Hydrogen reduction furnace scrubber.

BPT Limitations for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of molybdenum metal powder produced
Arsenic47.86021.300
Lead9.6174.580
Nickel43.97029.080
Selenium28.17012.600
Molybdenum[Reserved][Reserved]
Ammonia (as N)3,052.0001,342.000
Fluoride801.400455.700
Total suspended solids938.800446.500
pH( 1)( 1)

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

(e) Depleted rhenium scrubbing solution.

BPT Limitations for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of molybdenum sulfide roasted
Arsenic1.4970.666
Lead0.3010.143
Nickel1.3750.909
Selenium0.8810.394
Molybdenum[Reserved][Reserved]
Ammonia (as N)95.44041.960
Fluoride25.06014.250
Total suspended solids29.36013.960
pH( 1)( 1)

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

[50 FR 38355, Sept. 20, 1985, as amended at 55 FR 31701, Aug. 3, 1990]
§ 421.213 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best available technology economically achievable.

Except as provided in 40 CFR 125.30 through 125.32, any existing point source subject to this subpart shall achieve the following effluent limitations representing the degree of effluent reduction attainable by the application of the best available technology economically achievable:

(a) Molybdenum sulfide leachate.

BAT Limitations for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds million pounds) of molybdenum sulfide leached
Arsenic0.6440.287
Lead0.1300.060
Nickel0.2550.171
Selenium0.3800.171
Molybdenum[Reserved][Reserved]
Ammonia (as N)61.72027.130
Fluoride16.2109.214

(b) Roaster SO2 scrubber.

BAT Limitations for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per/million pounds) of molybdenum sulfide roasted
Arsenic2.3341.041
Lead0.4700.218
Nickel0.9240.621
Selenium1.3770.621
Molybdenum[Reserved][Reserved]
Ammonia (as N)223.80098.390
Fluoride58.77033.410

(c) Molybdic oxide leachate.

BAT Limitations for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per/million pounds) of molybdenum contained in molybdic oxide leached
Arsenic16.1007.182
Lead3.2441.506
Nickel6.3714.286
Selenium9.4994.286
Molybdenum[Reserved][Reserved]
Ammonia (as N)1,544.000678.800
Fluoride405.400230.500

(d) Hydrogen reduction furnace scrubber.

BAT Limitations for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per/million pounds) of molybdenum metal powder produced
Arsenic3.1831.420
Lead0.6410.298
Nickel1.2600.847
Selenium1.8780.847
Molybdenum[Reserved][Reserved].
Ammonia (as N)305.300134.200
Fluoride80.15045.570

(e) Depleted rhenium scrubbing solution.

BAT Limitations for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per/million pounds) of molybdenum sulfide roasted
Arsenic0.9950.444
Lead0.2010.093
Nickel0.3940.265
Selenium0.5870.265
Molybdenum[Reserved][Reserved].
Ammonia (as N)95.44041.960
Fluoride25.06014.250
[50 FR 38355, Sept. 20, 1985, as amended at 55 FR 31701, 31702, Aug. 3, 1990]
§ 421.214 - Standards of performance for new sources.

Any new source subject to this subpart shall achieve the following new source performance standards:

(a) Molybdenum sulfide leachate.

NSPS for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of molybdenum sulfide leached
Arsenic0.6440.287
Lead0.1300.060
Nickel0.2550.171
Selenium0.3800.171
Molybdenum[Reserved][Reserved].
Ammonia (as N)61.72027.130
Fluoride16.2109.214
Total suspended solids6.9455.556
pH( 1)( 1)

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

(b) Roaster SO2 scrubber.

NSPS for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of molybdenum sulfide roasted
Arsenic2.3341.041
Lead0.4700.218
Nickel0.9240.621
Selenium1.3770.621
Molybdenum[Reserved][Reserved].
Ammonia (as N)223.80098.390
Fluoride58.77033.410
Total suspended solids25.19020.150
pH( 1)( 1)

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

(c) Molybdic oxide leachate.

NSPS for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of molybdenum contained in molybdic oxide leached
Arsenic16.1007.182
Lead3.2441.506
Nickel6.3714.286
Selenium9.4994.286
Molybdenum[Reserved][Reserved].
Ammonia (as N)1,544.000678.800
Fluoride405.400230.500
Total suspended solids173.800139.000
pH( 1)( 1)

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

(d) Hydrogen reduction furnace scrubber.

NSPS for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of molybdenum metal powder produced
Arsenic3.1831.420
Lead0.6410.298
Nickel1.2600.847
Selenium1.8780.847
Molybdenum[Reserved][Reserved].
Ammonia (as N)305.300134.200
Fluoride80.15045.570
Total suspended solids34.35027.480
pH( 1)( 1)

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

(e) Depleted rhenium scrubbing solution.

NSPS for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of molybdenum sulfide roasted
Arsenic0.9950.444
Lead0.2010.093
Nickel0.3940.265
Selenium0.5870.265
Molybdenum[Reserved][Reserved].
Ammonia (as N)95.44041.960
Fluoride25.06014.250
Total suspended solids10.7408.592
pH( 1)( 1)

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

[50 FR 38355, Sept. 20, 1985, as amended at 55 FR 31702, Aug. 3, 1990]
§ 421.215 - [Reserved]
§ 421.216 - Pretreatment standards for new sources.

Except as provided in 40 CFR 403.7, any new source subject to this subpart which introduces pollutants into a publicly owned treatment works must comply with 40 CFR part 403 and achieve the following pretreatment standards for new sources. The mass of wastewater pollutants in primary molybdenum and rhenium process wastewater introduced into a POTW shall not exceed the following values:

(a) Molybdenum sulfide leachate.

PSNS for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of molybdenum sulfide leached
Arsenic0.6440.287
Lead0.1300.060
Nickel0.2550.171
Selenium0.3800.171
Molybdenum[Reserved][Reserved].
Ammonia (as N)61.72027.130
Fluoride16.2109.214

(b) Roaster SO2 scrubber.

PSNS for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of molybdenum sulfide roasted
Arsenic2.3341.041
Lead0.4700.218
Nickel0.9240.621
Selenium1.3770.621
Molybdenum[Reserved][Reserved].
Ammonia (as N)223.80098.390
Fluoride58.77033.410

(c) Molybdic oxide leachate.

PSNS for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of molybdenum contained in molybdic oxide leached
Arsenic16.1007.182
Lead3.2441.506
Nickel6.3714.286
Selenium9.4994.286
Molybdenum[Reserved][Reserved].
Ammonia (as N)1,544.000678.800
Fluoride405.400230.500

(d) Hydrogen reduction furnace scrubber.

PSNS for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of molybdenum metal powder produced
Arsenic3.1831.420
Lead0.6410.298
Nickel1.2600.847
Selenium1.8780.847
Molybdenum[Reserved][Reserved].
Ammonia (as N)305.300134.200
Fluoride80.15045.570

(e) Depleted rhenium scrubbing solution.

PSNS for the Primary Molybdenum and Rhenium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of molybdenum sulfide roasted
Arsenic0.9950.444
Lead0.2010.093
Nickel0.3940.265
Selenium0.5870.265
Molybdenum[Reserved][Reserved].
Ammonia (as N)95.44041.960
Fluoride25.06014.250
[50 FR 38355, Sept. 20, 1985, as amended at 55 FR 31702, 31703, Aug. 3, 1990]
§ 421.217 - [Reserved]
authority: Secs. 301, 304 (b), (c), (e), and (g), 306 (b) and (c), 307 (b) and (c), 308 and 501 of the Clean Water Act (the Federal Water Pollution Control Act Amendments of 1972, as amended by the Clean Water Act of 1977) and the Water Quality Act of 1987 (the “Act”); 33 U.S.C. 1311,1314,c,e,and, 1316 (b) andc, 1317 (b) andc,1318; 86 Stat. 816, Pub. L. 92-500; 91 Stat. 1567, Pub. L. 95-217; 101 Stat. 7, Pub. L. 100-4
source: 49 FR 8790, Mar. 8, 1984, unless otherwise noted.
cite as: 40 CFR 421.214