40 CFR 423.15 - New source performance standards (NSPS).

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§ 423.15 New source performance standards (NSPS).

(a)1982 NSPS. Any new source as of November 19, 1982, subject to paragraph (a) of this section, must achieve the following new source performance standards, in addition to the limitations in § 423.13 of this part, established on November 3, 2015. In the case of conflict, the more stringent requirements apply:

(1)pH. The pH of all discharges, except once through cooling water, shall be within the range of 6.0-9.0.

(2)PCBs. There shall be no discharge of polychlorinated biphenyl compounds such as those commonly used for transformer fluid.

(3)Low volume waste sources, FGD wastewater, flue gas mercury control wastewater, combustion residual leachate, and gasification wastewater. The quantity of pollutants discharged in low volume waste sources, FGD wastewater, flue gas mercury control wastewater, combustion residual leachate, and gasification wastewater shall not exceed the quantity determined by multiplying the flow of low volume waste sources times the concentration listed in the following table:

Pollutant or pollutant property NSPS
Maximum for any 1 day (mg/l) Average of daily
values for 30
consecutive days
shall not exceed
(mg/l)
TSS 100.0 30.0
Oil and grease 20.0 15.0

(4)Chemical metal cleaning wastes. The quantity of pollutants discharged in chemical metal cleaning wastes shall not exceed the quantity determined by multiplying the flow of chemical metal cleaning wastes times the concentration listed in the following table:

Pollutant or pollutant property NSPS
Maximum for
any 1 day
(mg/l)
Average of daily
values for 30
consecutive days
shall not exceed
(mg/l)
TSS 100.0 30.0
Oil and grease 20.0 15.0
Copper, total 1.0 1.0
Iron, total 1.0 1.0

(5) [Reserved]

(6)Bottom ash transport water. The quantity of pollutants discharged in bottom ash transport water shall not exceed the quantity determined by multiplying the flow of the bottom ash transport water times the concentration listed in the following table:

Pollutant or pollutant property NSPS
Maximum for
any 1 day
(mg/l)
Average of daily
values for 30
consecutive days
shall not exceed
(mg/l)
TSS 100.0 30.0
Oil and grease 20.0 15.0

(7)Fly ash transport water. There shall be no discharge of pollutants in fly ash transport water.

(8)

(i)Once through cooling water. For any plant with a total rated electric generating capacity of 25 or more megawatts, the quantity of pollutants discharged in once through cooling water from each discharge point shall not exceed the quantity determined by multiplying the flow of once through cooling water from each discharge point times the concentration listed in the following table:

Pollutant or pollutant property NSPS
Maximum concentrations
(mg/l)
Total residual chlorine 0.20

(ii) Total residual chlorine may only be discharged from any single generating unit for more than two hours per day when the discharger demonstrates to the permitting authority that discharge for more than two hours is required for macroinvertebrate control. Simultaneous multi-unit chlorination is permitted.

(9)

(i)Once through cooling water. For any plant with a total rated generating capacity of less than 25 megawatts, the quantity of pollutants discharged in once through cooling water shall not exceed the quantity determined by multiplying the flow of once through cooling water sources times the concentration listed in the following table:

Pollutant or pollutant property NSPS
Maximum concentration
(mg/l)
Average concentration
(mg/l)
Free available chlorine 0.5 0.2

(ii) Neither free available chlorine nor total residual chlorine may be discharged from any unit for more than two hours in any one day and not more than one unit in any plant may discharge free available or total residual chlorine at any one time unless the utility can demonstrate to the Regional Administrator or state, if the state has NPDES permit issuing authority, that the units in a particular location cannot operate at or below this level of chlorination.

(10)

(i)Cooling tower blowdown. The quantity of pollutants discharged in cooling tower blowdown shall not exceed the quantity determined by multiplying the flow of cooling tower blowdown times the concentration listed below:

Pollutant or pollutant property NSPS
Maximum concentration
(mg/l)
Average concentration
(mg/l)
Free available chlorine 0.5 0.2
Pollutant or pollutant property NSPS
Maximum for
any 1 day
(mg/l)
Average of daily
values for 30
consecutive days
shall not exceed
(mg/l)
The 126 priority pollutants (appendix A) contained in chemicals added for cooling tower maintenance, except: ( 1) ( 1)
Chromium, total 0.2 0.2
zinc, total 1.0 1.0

1 No detectable amount.

(ii) Neither free available chlorine nor total residual chlorine may be discharged from any unit for more than two hours in any one day and not more than one unit in any plant may discharge free available or total residual chlorine at any one time unless the utility can demonstrate to the Regional Administrator or state, if the state has NPDES permit issuing authority, that the units in a particular location cannot operate at or below this level of chlorination.

(iii) At the permitting authority's discretion, instead of the monitoring in 40 CFR 122.11(b), compliance with the standards for the 126 priority pollutants in paragraph (a)(10)(i) of this section may be determined by engineering calculations which demonstrate that the regulated pollutants are not detectable in the final discharge by the analytical methods in 40 CFR part 136.

(11)Coal pile runoff. Subject to the provisions of paragraph (a)(12) of this section, the quantity or quality of pollutants or pollutant parameters discharged in coal pile runoff shall not exceed the standards specified below:

Pollutant or pollutant property NSPS for any time
TSS not to exceed 50 mg/l.

(12)Coal pile runoff. Any untreated overflow from facilities designed, constructed, and operated to treat the coal pile runoff which results from a 10 year, 24 hour rainfall event shall not be subject to the standards in paragraph (a)(11) of this section.

(13) At the permitting authority's discretion, the quantity of pollutant allowed to be discharged may be expressed as a concentration limitation instead of any mass based limitations specified in paragraphs (a)(3) through (10) of this section. Concentration limits shall be based on the concentrations specified in this section.

(14) In the event that wastestreams from various sources are combined for treatment or discharge, the quantity of each pollutant or pollutant property controlled in paragraphs (a)(1) through (13) of this section attributable to each controlled waste source shall not exceed the specified limitation for that waste source.

(b)2015 NSPS. Any new source as of November 17, 2015, subject to paragraph (b) of this section, must achieve the following new source performance standards:

(1)pH. The pH of all discharges, except once through cooling water, shall be within the range of 6.0-9.0.

(2)PCBs. There shall be no discharge of polychlorinated biphenyl compounds such as those commonly used for transformer fluid.

(3)Low volume waste sources. The quantity of pollutants discharged from low volume waste sources shall not exceed the quantity determined by multiplying the flow of low volume waste sources times the concentration listed in the following table:

Pollutant or pollutant property NSPS
Maximum for
any 1 day
(mg/l)
Average of daily
values for 30
consecutive days
shall not exceed
(mg/l)
TSS 100.0 30.0
Oil and grease 20.0 15.0

(4)Chemical metal cleaning wastes. The quantity of pollutants discharged in chemical metal cleaning wastes shall not exceed the quantity determined by multiplying the flow of chemical metal cleaning wastes times the concentration listed in the following table:

Pollutant or pollutant property NSPS
Maximum for
any 1 day
(mg/l)
Average of daily
values for 30
consecutive days
shall not exceed
(mg/l)
TSS 100.0 30.0
Oil and grease 20.0 15.0
Copper, total 1.0 1.0
Iron, total 1.0 1.0

(5) [Reserved]

(6)Bottom ash transport water. There shall be no discharge of pollutants in bottom ash transport water. Whenever bottom ash transport water is used in any other plant process or is sent to a treatment system at the plant, the resulting effluent must comply with the discharge standard in this paragraph.

(7)Fly ash transport water. There shall be no discharge of pollutants in fly ash transport water. Whenever fly ash transport water is used in any other plant process or is sent to a treatment system at the plant, the resulting effluent must comply with the discharge standard in this paragraph.

(8)

(i)Once through cooling water. For any plant with a total rated electric generating capacity of 25 or more megawatts, the quantity of pollutants discharged in once through cooling water from each discharge point shall not exceed the quantity determined by multiplying the flow of once through cooling water from each discharge point times the concentration listed in the following table:

Pollutant or pollutant property NSPS
Maximum concentration
(mg/l)
Total residual chlorine 0.20

(ii) Total residual chlorine may only be discharged from any single generating unit for more than two hours per day when the discharger demonstrates to the permitting authority that discharge for more than two hours is required for macroinvertebrate control. Simultaneous multi-unit chlorination is permitted.

(9)

(i)Once through cooling water. For any plant with a total rated generating capacity of less than 25 megawatts, the quantity of pollutants discharged in once through cooling water shall not exceed the quantity determined by multiplying the flow of once through cooling water sources times the concentration listed in the following table:

Pollutant or pollutant property NSPS
Maximum concentration
(mg/l)
Average concentration
(mg/l)
Free available chlorine 0.5 0.2

(ii) Neither free available chlorine nor total residual chlorine may be discharged from any unit for more than two hours in any one day and not more than one unit in any plant may discharge free available or total residual chlorine at any one time unless the utility can demonstrate to the Regional Administrator or state, if the state has NPDES permit issuing authority, that the units in a particular location cannot operate at or below this level of chlorination.

(10)

(i)Cooling tower blowdown. The quantity of pollutants discharged in cooling tower blowdown shall not exceed the quantity determined by multiplying the flow of cooling tower blowdown times the concentration listed below:

Pollutant or pollutant property NSPS
Maximum concentration
(mg/l)
Average concentration
(mg/l)
Free available chlorine 0.5 0.2
Pollutant or pollutant property NSPS
Maximum for
any 1 day
(mg/l)
Average of daily
values for 30
consecutive days
shall not exceed
(mg/l)
The 126 priority pollutants (appendix A) contained in chemicals added for cooling tower maintenance, except: ( 1) ( 1)
Chromium, total 0.2 0.2
zinc, total 1.0 1.0

1 No detectable amount.

(ii) Neither free available chlorine nor total residual chlorine may be discharged from any unit for more than two hours in any one day and not more than one unit in any plant may discharge free available or total residual chlorine at any one time unless the utility can demonstrate to the Regional Administrator or state, if the state has NPDES permit issuing authority, that the units in a particular location cannot operate at or below this level of chlorination.

(iii) At the permitting authority's discretion, instead of the monitoring in 40 CFR 122.11(b), compliance with the standards for the 126 priority pollutants in paragraph (b)(10)(i) of this section may be determined by engineering calculations demonstrating that the regulated pollutants are not detectable in the final discharge by the analytical methods in 40 CFR part 136.

(11)Coal pile runoff. Subject to the provisions of paragraph (b)(12) of this section, the quantity or quality of pollutants or pollutant parameters discharged in coal pile runoff shall not exceed the standards specified below:

Pollutant or pollutant property NSPS for any time
TSS not to exceed 50 mg/l.

(12)Coal pile runoff. Any untreated overflow from facilities designed, constructed, and operated to treat the coal pile runoff which results from a 10 year, 24 hour rainfall event shall not be subject to the standards in paragraph (b)(11) of this section.

(13)FGD wastewater. The quantity of pollutants discharged in FGD wastewater shall not exceed the quantity determined by multiplying the flow of FGD wastewater times the concentration listed in the following table:

Pollutant or pollutant property NSPS
Maximum for
any 1 day
Average of daily
values for 30
consecutive days
shall not exceed
Arsenic, total (ug/L) 4
Mercury, total (ng/L) 39 24
Selenium, total (ug/L) 5
TDS (mg/L) 50 24

(14)Flue gas mercury control wastewater. There shall be no discharge of pollutants in flue gas mercury control wastewater. Whenever flue gas mercury control wastewater is used in any other plant process or is sent to a treatment system at the plant, the resulting effluent must comply with the discharge standard in this paragraph.

(15)Gasification wastewater. The quantity of pollutants discharged in gasification wastewater shall not exceed the quantity determined by multiplying the flow of gasification wastewater times the concentration listed in the following table:

Pollutant or pollutant property NSPS
Maximum for
any 1 day
Average of daily
values for 30
consecutive days
shall not exceed
Arsenic, total (ug/L) 4
Mercury, total (ng/L) 1.8 1.3
Selenium, total (ug/L) 453 227
Total dissolved solids (mg/L) 38 22

(16)Combustion residual leachate. The quantity of pollutants discharged in combustion residual leachate shall not exceed the quantity determined by multiplying the flow of combustion residual leachate times the concentration listed in the following table:

Pollutant or pollutant property NSPS
Maximum for
any 1 day
Average of daily
values for 30
consecutive days
shall not exceed
Arsenic, total (ug/L) 11 8
Mercury, total (ng/L) 788 356

(17) At the permitting authority's discretion, the quantity of pollutant allowed to be discharged may be expressed as a concentration limitation instead of any mass based limitations specified in paragraphs (b)(3) through (16) of this section. Concentration limits shall be based on the concentrations specified in this section.

(18) In the event that wastestreams from various sources are combined for treatment or discharge, the quantity of each pollutant or pollutant property controlled in paragraphs (b)(1) through (16) of this section attributable to each controlled waste source shall not exceed the specified limitation for that waste source.

(The information collection requirements contained in paragraphs (a)(8)(ii), (a)(9)(ii), and (a)(10)(ii), (b)(8)(ii), (b)(9)(ii), and (b)(10)(ii) were approved by the Office of Management and Budget under control number 2040-0040. The information collection requirements contained in paragraphs (a)(10)(iii) and (b)(10)(iii) were approved under control number 2040-0033.)

[ 80 FR 67896, Nov. 3, 2015]

This is a list of United States Code sections, Statutes at Large, Public Laws, and Presidential Documents, which provide rulemaking authority for this CFR Part.

This list is taken from the Parallel Table of Authorities and Rules provided by GPO [Government Printing Office].

It is not guaranteed to be accurate or up-to-date, though we do refresh the database weekly. More limitations on accuracy are described at the GPO site.


United States Code
Statutes at Large

Title 40 published on 2015-08-22

The following are ALL rules, proposed rules, and notices (chronologically) published in the Federal Register relating to 40 CFR Part 423 after this date.

  • 2015-11-03; vol. 80 # 212 - Tuesday, November 3, 2015
    1. 80 FR 67838 - Effluent Limitations Guidelines and Standards for the Steam Electric Power Generating Point Source Category
      GPO FDSys XML | Text
      ENVIRONMENTAL PROTECTION AGENCY
      Final rule.
      The final rule is effective on January 4, 2016. In accordance with 40 CFR part 23, this regulation shall be considered issued for purposes of judicial review at 1 p.m. Eastern time on November 17, 2015. Under section 509(b)(1) of the CWA, judicial review of this regulation can be had only by filing a petition for review in the U.S. Court of Appeals within 120 days after the regulation is considered issued for purposes of judicial review. Under section 509(b)(2), the requirements in this regulation may not be challenged later in civil or criminal proceedings brought by EPA to enforce these requirements.
      40 CFR Part 423