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Title 40

Displaying title 40, up to date as of 6/15/2026. Title 40 was last amended 6/15/2026.
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§ 421.284 Standards of performance for new sources.

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

(a) Tantalum alloy leach and rinse.

NSPS for the Secondary Tantalum Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of tantalum powder produced
Copper 295.200 140.700
Lead 64.570 29.980
Nickel 126.800 85.320
Zinc 235.200 96.850
Tantalum 103.800
Total suspended solids 3,459.000 2,767.000
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(b) Capacitor leach and rinse.

NSPS for the Secondary Tantalum Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of tantalum powder produced from leaching
Copper 25.860 12.320
Lead 5.656 2.626
Nickel 11.110 7.474
Zinc 20.600 8.484
Tantalum 9.090
Total suspended solids 303.000 242.400
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(c) Tantalum sludge leach and rinse.

NSPS for the Secondary Tantalum Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of equivalent pure tantalum powder produced
Copper 262.800 125.200
Lead 57.480 26.690
Nickel 112.900 75.960
Zinc 209.400 86.230
Tantalum 92.390
Total suspended solids 3,080.000 2,464.000
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(d) Tantalum powder acid wash and rinse.

NSPS for the Secondary Tantalum Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of tantalum powder produced
Copper 0.448 0.214
Lead 0.098 0.046
Nickel 0.193 0.130
Zinc 0.357 0.147
Tantalum 0.158
Total suspended solids 5.250 4.200
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(e) Leaching wet air pollution control.

NSPS for the Secondary Tantalum Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of equivalent pure tantalum powder produced
Copper 6.246 2.977
Lead 1.366 0.634
Nickel 2.684 1.806
Zinc 4.978 2.050
Tantalum 2.196
Total suspended solids 73.200 58.560
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.