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Title 40 Part 423

Title 40 → Chapter I → Subchapter N → Part 423

Electronic Code of Federal Regulations e-CFR

Title 40 Part 423

e-CFR data is current as of December 12, 2018

Title 40Chapter ISubchapter N → Part 423


Title 40: Protection of Environment


§423.10   Applicability.

The provisions of this part apply to discharges resulting from the operation of a generating unit by an establishment whose generation of electricity is the predominant source of revenue or principal reason for operation, and whose generation of electricity results primarily from a process utilizing fossil-type fuel (coal, oil, or gas), fuel derived from fossil fuel (e.g., petroleum coke, synthesis gas), or nuclear fuel in conjunction with a thermal cycle employing the steam water system as the thermodynamic medium. This part applies to discharges associated with both the combustion turbine and steam turbine portions of a combined cycle generating unit.

[80 FR 67893, Nov. 3, 2015]

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§423.11   Specialized definitions.

In addition to the definitions set forth in 40 CFR part 401, the following definitions apply to this part:

(a) The term total residual chlorine (or total residual oxidants for intake water with bromides) means the value obtained using any of the “chlorine—total residual” methods in Table IB in 40 CFR 136.3(a), or other methods approved by the permitting authority.

(b) The term low volume waste sources means, taken collectively as if from one source, wastewater from all sources except those for which specific limitations or standards are otherwise established in this part. Low volume waste sources include, but are not limited to, the following: Wastewaters from ion exchange water treatment systems, water treatment evaporator blowdown, laboratory and sampling streams, boiler blowdown, floor drains, cooling tower basin cleaning wastes, recirculating house service water systems, and wet scrubber air pollution control systems whose primary purpose is particulate removal. Sanitary wastes, air conditioning wastes, and wastewater from carbon capture or sequestration systems are not included in this definition.

(c) The term chemical metal cleaning waste means any wastewater resulting from the cleaning of any metal process equipment with chemical compounds, including, but not limited to, boiler tube cleaning.

(d) The term metal cleaning waste means any wastewater resulting from cleaning [with or without chemical cleaning compounds] any metal process equipment including, but not limited to, boiler tube cleaning, boiler fireside cleaning, and air preheater cleaning.

(e) The term fly ash means the ash that is carried out of the furnace by a gas stream and collected by a capture device such as a mechanical precipitator, electrostatic precipitator, or fabric filter. Economizer ash is included in this definition when it is collected with fly ash. Ash is not included in this definition when it is collected in wet scrubber air pollution control systems whose primary purpose is particulate removal.

(f) The term bottom ash means the ash, including boiler slag, which settles in the furnace or is dislodged from furnace walls. Economizer ash is included in this definition when it is collected with bottom ash.

(g) The term once through cooling water means water passed through the main cooling condensers in one or two passes for the purpose of removing waste heat.

(h) The term recirculated cooling water means water which is passed through the main condensers for the purpose of removing waste heat, passed through a cooling device for the purpose of removing such heat from the water and then passed again, except for blowdown, through the main condenser.

(i) The term 10 year, 24/hour rainfall event means a rainfall event with a probable recurrence interval of once in ten years as defined by the National Weather Service in Technical Paper No. 40. Rainfall Frequency Atlas of the United States, May 1961 or equivalent regional rainfall probability information developed therefrom.

(j) The term blowdown means the minimum discharge of recirculating water for the purpose of discharging materials contained in the water, the further buildup of which would cause concentration in amounts exceeding limits established by best engineering practices.

(k) The term average concentration as it relates to chlorine discharge means the average of analyses made over a single period of chlorine release which does not exceed two hours.

(l) The term free available chlorine means the value obtained using any of the “chlorine—free available” methods in Table IB in 40 CFR 136.3(a) where the method has the capability of measuring free available chlorine, or other methods approved by the permitting authority.

(m) The term coal pile runoff means the rainfall runoff from or through any coal storage pile.

(n) The term flue gas desulfurization (FGD) wastewater means any wastewater generated specifically from the wet flue gas desulfurization scrubber system that comes into contact with the flue gas or the FGD solids, including but not limited to, the blowdown from the FGD scrubber system, overflow or underflow from the solids separation process, FGD solids wash water, and the filtrate from the solids dewatering process. Wastewater generated from cleaning the FGD scrubber, cleaning FGD solids separation equipment, cleaning FGD solids dewatering equipment, or that is collected in floor drains in the FGD process area is not considered FGD wastewater.

(o) The term flue gas mercury control wastewater means any wastewater generated from an air pollution control system installed or operated for the purpose of removing mercury from flue gas. This includes fly ash collection systems when the particulate control system follows sorbent injection or other controls to remove mercury from flue gas. FGD wastewater generated at plants using oxidizing agents to remove mercury in the FGD system and not in a separate FGMC system is not included in this definition.

(p) The term transport water means any wastewater that is used to convey fly ash, bottom ash, or economizer ash from the ash collection or storage equipment, or boiler, and has direct contact with the ash. Transport water does not include low volume, short duration discharges of wastewater from minor leaks (e.g., leaks from valve packing, pipe flanges, or piping) or minor maintenance events (e.g., replacement of valves or pipe sections).

(q) The term gasification wastewater means any wastewater generated at an integrated gasification combined cycle operation from the gasifier or the syngas cleaning, combustion, and cooling processes. Gasification wastewater includes, but is not limited to the following: Sour/grey water; CO2/steam stripper wastewater; sulfur recovery unit blowdown, and wastewater resulting from slag handling or fly ash handling, particulate removal, halogen removal, or trace organic removal. Air separation unit blowdown, noncontact cooling water, and runoff from fuel and/or byproduct piles are not considered gasification wastewater. Wastewater that is collected intermittently in floor drains in the gasification process area from leaks, spills, and cleaning occurring during normal operation of the gasification operation is not considered gasification wastewater.

(r) The term combustion residual leachate means leachate from landfills or surface impoundments containing combustion residuals. Leachate is composed of liquid, including any suspended or dissolved constituents in the liquid, that has percolated through waste or other materials emplaced in a landfill, or that passes through the surface impoundment's containment structure (e.g., bottom, dikes, berms). Combustion residual leachate includes seepage and/or leakage from a combustion residual landfill or impoundment unit. Combustion residual leachate includes wastewater from landfills and surface impoundments located on non-adjoining property when under the operational control of the permitted facility.

(s) The term oil-fired unit means a generating unit that uses oil as the primary or secondary fuel source and does not use a gasification process or any coal or petroleum coke as a fuel source. This definition does not include units that use oil only for start up or flame-stabilization purposes.

(t) The phrase “as soon as possible” means November 1, 2018 (except for purposes of §423.13(g)(1)(i) and (k)(1)(i), and §423.16(e) and (g), in which case it means November 1, 2020), unless the permitting authority establishes a later date, after receiving information from the discharger, which reflects a consideration of the following factors:

(1) Time to expeditiously plan (including to raise capital), design, procure, and install equipment to comply with the requirements of this part.

(2) Changes being made or planned at the plant in response to:

(i) New source performance standards for greenhouse gases from new fossil fuel-fired electric generating units, under sections 111, 301, 302, and 307(d)(1)(C) of the Clean Air Act, as amended, 42 U.S.C. 7411, 7601, 7602, 7607(d)(1)(C);

(ii) Emission guidelines for greenhouse gases from existing fossil fuel-fired electric generating units, under sections 111, 301, 302, and 307(d) of the Clean Air Act, as amended, 42 U.S.C. 7411, 7601, 7602, 7607(d); or

(iii) Regulations that address the disposal of coal combustion residuals as solid waste, under sections 1006(b), 1008(a), 2002(a), 3001, 4004, and 4005(a) of the Solid Waste Disposal Act of 1970, as amended by the Resource Conservation and Recovery Act of 1976, as amended by the Hazardous and Solid Waste Amendments of 1984, 42 U.S.C. 6906(b), 6907(a), 6912(a), 6944, and 6945(a).

(3) For FGD wastewater requirements only, an initial commissioning period for the treatment system to optimize the installed equipment.

(4) Other factors as appropriate.

[47 FR 52304, Nov. 19, 1982, as amended at 77 FR 29834, May 18, 2012; 80 FR 67893, Nov. 3, 2015; 82 FR 43500, Sept. 18, 2017]

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§423.12   Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available (BPT).

(a) In establishing the limitations set forth in this section, EPA took into account all information it was able to collect, develop and solicit with respect to factors (such as age and size of plant, utilization of facilities, raw materials, manufacturing processes, non-water quality environmental impacts, control and treatment technology available, energy requirements and costs) which can affect the industry subcategorization and effluent levels established. It is, however, possible that data which would affect these limitations have not been available and, as a result, these limitations should be adjusted for certain plants in this industry. An individual discharger or other interested person may submit evidence to the Regional Administrator (or to the State, if the State has the authority to issue NPDES permits) that factors relating to the equipment or facilities involved, the process applied, or other such factors related to such discharger are fundamentally different from the factors considered in the establishment of the guidelines. On the basis of such evidence or other available information, the Regional Administrator (or the State) will make a written finding that such factors are or are not fundamentally different for that facility compared to those specified in the Development Document. If such fundamentally different factors are found to exist, the Regional Administrator or the State shall establish for the discharger effluent limitations in the NPDES Permit either more or less stringent than the limitations established herein, to the extent dictated by such fundamentally different factors. Such limitations must be approved by the Administrator of the Environmental Protection Agency. The Administrator may approve or disapprove such limitations, specify other limitations, or initiate proceedings to revise these regulations. The phrase “other such factors” appearing above may include significant cost differentials. In no event may a discharger's impact on receiving water quality be considered as a factor under this paragraph.

(b) Any existing point source subject to this subpart must achieve the following effluent limitations representing the degree of effluent reduction by the application of the best practicable control technology currently available (BPT):

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

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

(3) 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 lised in the following table:

Pollutant or pollutant propertyBPT effluent limitations
Maximum for any 1 day (mg/l)Average of daily values for 30 consecutive days shall not exceed (mg/l)
TSS100.030.0
Oil and grease20.015.0

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

Pollutant or pollutant propertyBPT effluent limitations
Maximum for any 1 day (mg/l)Average of daily values for 30 consecutive days shall not exceed (mg/l)
TSS100.030.0
Oil and grease20.015.0

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

Pollutant or pollutant propertyBPT effluent limitations
Maximum for any 1 day (mg/l)Average of daily values for 30 consecutive days shall not exceed (mg/l)
TSS100.030.0
Oil and grease20.015.0
Copper, total1.01.0
Iron, total1.01.0

(6) 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 concentation listed in the following table:

Pollutant or pollutant propertyBPT effluent limitations
Maximum concentration (mg/l)Average concentration (mg/l)
Free available chlorine0.50.2

(7) The quantity of pollutants discharged in cooling tower blowdown shall not exceed the quantity determined by multiplying the flow of cooling tower blowdown sources times the concentration listed in the following table:

Pollutant or pollutant propertyBPT effluent limitations
Maximum concentration (mg/l)Average concentration (mg/l)
Free available chlorine0.50.2

(8) 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 or chlorination.

(9) Subject to the provisions of paragraph (b)(10) of this section, the following effluent limitations shall apply to the point source discharges of coal pile runoff:

Pollutant or pollutant propertyBPT effluent limitations
Maximum concentration for any time (mg/l)
TSS50

(10) Any untreated overflow from facilities designed, constructed, and operated to treat the volume of coal pile runoff which is associated with a 10 year, 24 hour rainfall event shall not be subject to the limitations in paragraph (b)(9) of this section.

(11) The quantity of pollutants discharged in FGD wastewater, flue gas mercury control wastewater, combustion residual leachate, or gasification wastewater shall not exceed the quantity determined by multiplying the flow of the applicable wastewater times the concentration listed in the following table:

Pollutant or pollutant propertyBPT Effluent limitations
Maximum for
any 1 day
(mg/l)
Average of daily
values for 30
consecutive days
shall not exceed
(mg/l)
TSS100.030.0
Oil and grease20.015.0

(12) At the permitting authority's discretion, the quantity of pollutant allowed to be discharged may be expressed as a concentration limitation instead of the mass-based limitations specified in paragraphs (b)(3) through (b)(7), and (b)(11), of this section. Concentration limitations shall be those concentrations specified in this section.

(13) 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 (b)(12) of this section attributable to each controlled waste source shall not exceed the specified limitations for that waste source.

(The information collection requirements contained in paragraph (a) were approved by the Office of Management and Budget under control number 2000-0194)

[47 FR 52304, Nov. 19, 1982, as amended at 48 FR 31404, July 8, 1983; 80 FR 67894, Nov. 3, 2015]

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§423.13   Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best available technology economically achievable (BAT).

Except as provided in 40 CFR 125.30 through 125.32, any existing point source subject to this part must achieve the following effluent limitations representing the degree of effluent reduction attainable by the application of the best available technology economically achievable (BAT).

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

(b)(1) 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 propertyBAT Effluent Limitations
Maximum concentration (mg/l)
Total residual chlorine0.20

(2) Total residual chlorine may not be discharged from any single generating unit for more than two hours per day unless 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.

(c)(1) 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 propertyBAT effluent limitations
Maximum concentration (mg/l)Average concentration (mg/l)
Free available chlorine0.50.2

(2) 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.

(d)(1) 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 propertyBAT effluent limitations
Maximum concentration (mg/l)Average concentration (mg/l)
Free available chlorine0.50.2
Pollutant or pollutant propertyMaximum 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, total0.20.2
Zinc, total1.01.0

1No detectable amount.

(2) 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.

(3) At the permitting authority's discretion, instead of the monitoring specified in 40 CFR 122.11(b) compliance with the limitations for the 126 priority pollutants in paragraph (d)(1) 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.

(e) 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 propertyBAT effluent limitations
Maximum for any 1 day (mg/l)Average of daily values for 30 consecutive days shall not exceed −(mg/l)
Copper, total1.01.0
Iron, total1.01.0

(f) [Reserved—Nonchemical Metal Cleaning Wastes].

(g)(1)(i) FGD wastewater. Except for those discharges to which paragraph (g)(2) or (g)(3) of this section applies, the quantity of pollutants in FGD wastewater shall not exceed the quantity determined by multiplying the flow of FGD wastewater times the concentration listed in the table following this paragraph (g)(1)(i). Dischargers must meet the effluent limitations for FGD wastewater in this paragraph by a date determined by the permitting authority that is as soon as possible beginning November 1, 2020, but no later than December 31, 2023. These effluent limitations apply to the discharge of FGD wastewater generated on and after the date determined by the permitting authority for meeting the effluent limitations, as specified in this paragraph.

Pollutant or pollutant propertyBAT Effluent limitations
Maximum for
any 1 day
Average of daily
values for 30
consecutive days
shall not exceed
Arsenic, total (ug/L)118
Mercury, total (ng/L)788356
Selenium, total (ug/L)2312
Nitrate/nitrite as N (mg/L)17.04.4

(ii) For FGD wastewater generated before the date determined by the permitting authority, as specified in paragraph (g)(1)(i), 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 for TSS in §423.12(b)(11).

(2) For any electric generating unit with a total nameplate capacity of less than or equal to 50 megawatts or that is an oil-fired unit, 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 for TSS in §423.12(b)(11).

(3)(i) For dischargers who voluntarily choose to meet the effluent limitations for FGD wastewater in this paragraph, the quantity of pollutants in FGD wastewater shall not exceed the quantity determined by multiplying the flow of FGD wastewater times the concentration listed in the table following this paragraph (g)(3)(i). Dischargers who choose to meet the effluent limitations for FGD wastewater in this paragraph must meet such limitations by December 31, 2023. These effluent limitations apply to the discharge of FGD wastewater generated on and after December 31, 2023.

Pollutant or pollutant propertyBAT Effluent limitations
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)3924
Selenium, total (ug/L)5
TDS (mg/L)5024

(ii) For discharges of FGD wastewater generated before December 31, 2023, 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 for TSS in §423.12(b)(11).

(h)(1)(i) Fly ash transport water. Except for those discharges to which paragraph (h)(2) of this section applies, or when the fly ash transport water is used in the FGD scrubber, there shall be no discharge of pollutants in fly ash transport water. Dischargers must meet the discharge limitation in this paragraph by a date determined by the permitting authority that is as soon as possible beginning November 1, 2018, but no later than December 31, 2023. This limitation applies to the discharge of fly ash transport water generated on and after the date determined by the permitting authority for meeting the discharge limitation, as specified in this paragraph. Whenever fly ash transport water is used in any other plant process or is sent to a treatment system at the plant (except when it is used in the FGD scrubber), the resulting effluent must comply with the discharge limitation in this paragraph. When the fly ash transport water is used in the FGD scrubber, the quantity of pollutants in fly ash transport water shall not exceed the quantity determined by multiplying the flow of fly ash transport water times the concentration listed in the table in paragraph (g)(1)(i) of this section.

(ii) For discharges of fly ash transport water generated before the date determined by the permitting authority, as specified in paragraph (h)(1)(i) of this section, the quantity of pollutants discharged in fly ash transport water shall not exceed the quantity determined by multiplying the flow of fly ash transport water times the concentration listed for TSS in §423.12(b)(4).

(2) For any electric generating unit with a total nameplate generating capacity of less than or equal to 50 megawatts or that is an oil-fired unit, the quantity of pollutants discharged in fly ash transport water shall not exceed the quantity determined by multiplying the flow of fly ash transport water times the concentration listed for TSS in §423.12(b)(4).

(i)(1)(i) Flue gas mercury control wastewater. Except for those discharges to which paragraph (i)(2) of this section applies, there shall be no discharge of pollutants in flue gas mercury control wastewater. Dischargers must meet the discharge limitation in this paragraph by a date determined by the permitting authority that is as soon as possible beginning November 1, 2018, but no later than December 31, 2023. This limitation applies to the discharge of flue gas mercury control wastewater generated on and after the date determined by the permitting authority for meeting the discharge limitation, as specified in this paragraph. 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 limitation in this paragraph.

(ii) For discharges of flue gas mercury control wastewater generated before the date determined by the permitting authority, as specified in paragraph (i)(1)(i) of this section, the quantity of pollutants discharged in flue gas mercury control wastewater shall not exceed the quantity determined by multiplying the flow of flue gas mercury control wastewater times the concentration for TSS listed in §423.12(b)(11).

(2) For any electric generating unit with a total nameplate generating capacity of less than or equal to 50 megawatts or that is an oil-fired unit, the quantity of pollutants discharged in flue gas mercury control wastewater shall not exceed the quantity determined by multiplying the flow of flue gas mercury control wastewater times the concentration for TSS listed in §423.12(b)(11).

(j)(1)(i) Gasification wastewater. Except for those discharges to which paragraph (j)(2) of this section applies, the quantity of pollutants in gasification wastewater shall not exceed the quantity determined by multiplying the flow of gasification wastewater times the concentration listed in the table following this paragraph (j)(1)(i). Dischargers must meet the effluent limitations in this paragraph by a date determined by the permitting authority that is as soon as possible beginning November 1, 2018, but no later than December 31, 2023. These effluent limitations apply to the discharge of gasification wastewater generated on and after the date determined by the permitting authority for meeting the effluent limitations, as specified in this paragraph.

Pollutant or pollutant propertyBAT Effluent limitations
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)1.81.3
Selenium, total (ug/L)453227
Total dissolved solids (mg/L)3822

(ii) For discharges of gasification wastewater generated before the date determined by the permitting authority, as specified in paragraph (j)(1)(i) of this section, the quantity of pollutants discharged in gasification wastewater shall not exceed the quantity determined by multiplying the flow of gasification wastewater times the concentration for TSS listed in §423.12(b)(11).

(2) For any electric generating unit with a total nameplate generating capacity of less than or equal to 50 megawatts or that is an oil-fired unit, 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 for TSS in §423.12(b)(11).

(k)(1)(i) Bottom ash transport water. Except for those discharges to which paragraph (k)(2) of this section applies, or when the bottom ash transport water is used in the FGD scrubber, there shall be no discharge of pollutants in bottom ash transport water. Dischargers must meet the discharge limitation in this paragraph by a date determined by the permitting authority that is as soon as possible beginning November 1, 2020, but no later than December 31, 2023. This limitation applies to the discharge of bottom ash transport water generated on and after the date determined by the permitting authority for meeting the discharge limitation, as specified in this paragraph. Whenever bottom ash transport water is used in any other plant process or is sent to a treatment system at the plant (except when it is used in the FGD scrubber), the resulting effluent must comply with the discharge limitation in this paragraph. When the bottom ash transport water is used in the FGD scrubber, the quantity of pollutants in bottom ash transport water shall not exceed the quantity determined by multiplying the flow of bottom ash transport water times the concentration listed in the table in paragraph (g)(1)(i) of this section.

(ii) For discharges of bottom ash transport water generated before the date determined by the permitting authority, as specified in paragraph (k)(1)(i) of this section, the quantity of pollutants discharged in bottom ash transport water shall not exceed the quantity determined by multiplying the flow of bottom ash transport water times the concentration for TSS listed in §423.12(b)(4).

(2) For any electric generating unit with a total nameplate generating capacity of less than or equal to 50 megawatts or that is an oil-fired unit, the quantity of pollutants discharged in bottom ash transport water shall not exceed the quantity determined by multiplying the flow of the applicable wastewater times the concentration for TSS listed in §423.12(b)(4).

(l) 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 for TSS listed in §423.12(b)(11).

(m) 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) through (l) of this section. Concentration limitations shall be those concentrations specified in this section.

(n) 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) through (m) 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 (c)(2) and (d)(2) were approved by the Office of Management and Budget under control number 2040-0040. The information collection requirements contained in paragraph (d)(3) were approved under control number 2040-0033)

[47 FR 52304, Nov. 19, 1982, as amended at 48 FR 31404, July 8, 1983; 80 FR 67894, Nov. 3, 2015; 82 FR 43500, Sept. 18, 2017]

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§423.14   Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best conventional pollutant control technology (BCT). [Reserved]

§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 propertyNSPS
Maximum for any 1 day (mg/l)Average of daily
values for 30
consecutive days
shall not exceed
(mg/l)
TSS100.030.0
Oil and grease20.015.0

(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 propertyNSPS
Maximum for
any 1 day
(mg/l)
Average of daily
values for 30
consecutive days
shall not exceed
(mg/l)
TSS100.030.0
Oil and grease20.015.0
Copper, total1.01.0
Iron, total1.01.0

(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 propertyNSPS
Maximum for
any 1 day
(mg/l)
Average of daily
values for 30
consecutive days
shall not exceed
(mg/l)
TSS100.030.0
Oil and grease20.015.0

(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 propertyNSPS
Maximum concentrations
(mg/l)
Total residual chlorine0.20

(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 propertyNSPS
Maximum concentration
(mg/l)
Average concentration
(mg/l)
Free available chlorine0.50.2

(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 propertyNSPS
Maximum concentration
(mg/l)
Average concentration
(mg/l)
Free available chlorine0.50.2
Pollutant or pollutant propertyNSPS
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, total0.20.2
zinc, total1.01.0

1No 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 propertyNSPS for any time
TSSnot 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 propertyNSPS
Maximum for
any 1 day
(mg/l)
Average of daily
values for 30
consecutive days
shall not exceed
(mg/l)
TSS100.030.0
Oil and grease20.015.0

(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 propertyNSPS
Maximum for
any 1 day
(mg/l)
Average of daily
values for 30
consecutive days
shall not exceed
(mg/l)
TSS100.030.0
Oil and grease20.015.0
Copper, total1.01.0
Iron, total1.01.0

(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 propertyNSPS
Maximum concentration
(mg/l)
Total residual chlorine0.20

(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 propertyNSPS
Maximum concentration
(mg/l)
Average concentration
(mg/l)
Free available chlorine0.50.2

(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 propertyNSPS
Maximum concentration
(mg/l)
Average concentration
(mg/l)
Free available chlorine0.50.2
Pollutant or pollutant propertyNSPS
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, total0.20.2
zinc, total1.01.0

1No 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 propertyNSPS for any time
TSSnot 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 propertyNSPS
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)3924
Selenium, total (ug/L)5
TDS (mg/L)5024

(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 propertyNSPS
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)1.81.3
Selenium, total (ug/L)453227
Total dissolved solids (mg/L)3822

(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 propertyNSPS
Maximum for
any 1 day
Average of daily
values for 30
consecutive days
shall not exceed
Arsenic, total (ug/L)118
Mercury, total (ng/L)788356

(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]

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§423.16   Pretreatment standards for existing sources (PSES).

Except as provided in 40 CFR 403.7 and 403.13, any existing 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 existing sources (PSES) by July 1, 1984:

(a) There shall be no discharge of polychlorinated biphenol compounds such as those used for transformer fluid.

(b) The pollutants discharged in chemical metal cleaning wastes shall not exceed the concentration listed in the following table:

Pollutant or pollutant propertyPSES pretreatment standards
Maximum for 1 day (mg/l)
Copper, total1.0

(c) [Reserved—Nonchemical Metal Cleaning Wastes].

(d)(1) The pollutants discharged in cooling tower blowdown shall not exceed the concentration listed in the following table:

Pollutant or pollutant propertyPSES pretreatment standards
Maximum for any time (mg/l)
The 126 priority pollutants (Appendix A) contained in chemicals added for cooling tower maintenance, except:(1)
Chromium, total0.2
Zinc, total1.0

1No detectable amount.

(2) At the permitting authority's discretion, instead of the monitoring in 40 CFR 122.11(b), compliance with the limitations for the 126 priority pollutants in paragraph (d)(1) 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.

(e) FGD wastewater. For any electric generating unit with a total nameplate generating capacity of more than 50 megawatts and that is not an oil-fired unit, the quantity of pollutants in FGD wastewater shall not exceed the quantity determined by multiplying the flow of FGD wastewater times the concentration listed in the table following this paragraph (e). Dischargers must meet the standards in this paragraph by November 1, 2020. These standards apply to the discharge of FGD wastewater generated on and after November 1, 2020.

Pollutant or pollutant propertyPSES
Maximum for
any 1 day
Average of daily
values for 30
consecutive days
shall not exceed
Arsenic, total (ug/L)118
Mercury, total (ng/L)788356
Selenium, total (ug/L)2312
Nitrate/nitrite as N (mg/L)17.04.4

(f) Fly ash transport water. Except when the fly ash transport water is used in the FGD scrubber, for any electric generating unit with a total nameplate generating capacity of more than 50 megawatts and that is not an oil-fired unit, there shall be no discharge of pollutants in fly ash transport water. This standard applies to the discharge of fly ash transport water generated on and after November 1, 2018. Whenever fly ash transport water is used in any other plant process or is sent to a treatment system at the plant (except when it is used in the FGD scrubber), the resulting effluent must comply with the discharge standard in this paragraph. When the fly ash transport water is used in the FGD scrubber, the quantity of pollutants in fly ash transport water shall not exceed the quantity determined by multiplying the flow of fly ash transport water times the concentration listed in the table in paragraph (e) of this section.

(g) Bottom ash transport water. Except when the bottom ash transport water is used in the FGD scrubber, for any electric generating unit with a total nameplate generating capacity of more than 50 megawatts and that is not an oil-fired unit, there shall be no discharge of pollutants in bottom ash transport water. This standard applies to the discharge of bottom ash transport water generated on and after November 1, 2020. Whenever bottom ash transport water is used in any other plant process or is sent to a treatment system at the plant (except when it is used in the FGD scrubber), the resulting effluent must comply with the discharge standard in this paragraph. When the bottom ash transport water is used in the FGD scrubber, the quantity of pollutants in bottom ash transport water shall not exceed the quantity determined by multiplying the flow of bottom ash transport water times the concentration listed in the table in paragraph (e) of this section.

(h) Flue gas mercury control wastewater. For any electric generating unit with a total nameplate generating capacity of more than 50 megawatts and that is not an oil-fired unit, there shall be no discharge of pollutants in flue gas mercury control wastewater. This standard applies to the discharge of flue gas mercury control wastewater generated on and after November 1, 2018. 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.

(i) Gasification wastewater. For any electric generating unit with a total nameplate generating capacity of more than 50 megawatts and that is not an oil-fired unit, the quantity of pollutants in gasification wastewater shall not exceed the quantity determined by multiplying the flow of gasification wastewater times the concentration listed in the table following this paragraph (i). Dischargers must meet the standards in this paragraph by November 1, 2018. These standards apply to the discharge of gasification wastewater generated on and after November 1, 2018.

Pollutant or pollutant propertyPSES
Maximum for
any 1 day
Average of daily
values for 30
consecutive days
shall not exceed
Arsenic, total (µg/L)4
Mercury, total (ng/L)1.81.3
Selenium, total (µg/L)453227
Total dissolved solids (mg/L)3822

[47 FR 52304, Nov. 19, 1982, as amended at 80 FR 67901, Nov. 3, 2015; 82 FR 43500, Sept. 18, 2017]

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§423.17   Pretreatment standards for new sources (PSNS).

(a) 1982 PSNS. Except as provided in 40 CFR 403.7, any new source as of October 14, 1980, subject to paragraph (a) of this section, which introduces pollutants into a publicly owned treatment works, must comply with 40 CFR part 403, the following pretreatment standards for new sources, and the PSES in §423.16, established on November 3, 2015. In the case of conflict, the more stringent standards apply:

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

(2) Chemical metal cleaning wastes. The pollutants discharged in chemical metal cleaning wastes shall not exceed the concentration listed in the following table:

Pollutant or pollutant propertyPSNS
Maximum for any 1 day
(mg/L)
Copper, total1.0

(3) [Reserved]

(4)(i) Cooling tower blowdown. The pollutants discharged in cooling tower blowdown shall not exceed the concentration listed in the following table:

Pollutant or pollutant propertyPSNS
Maximum for any time
(mg/L)
The 126 priority pollutants (appendix A) contained in chemicals added for cooling tower maintenance, except:(1)
Chromium, total0.2
zinc, total1.0

1No detectable amount.

(ii) 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)(4)(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.

(5) Fly ash transport water. There shall be no discharge of wastewater pollutants from fly ash transport water.

(b) 2015 PSNS. Except as provided in 40 CFR 403.7, any new source as of June 7, 2013, subject to this paragraph (b), which introduces pollutants into a publicly owned treatment works must comply with 40 CFR part 403 and the following pretreatment standards for new sources:

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

(2) Chemical metal cleaning wastes. The pollutants discharged in chemical metal cleaning wastes shall not exceed the concentration listed in the following table:

Pollutant or pollutant propertyPSNS
Maximum for 1 day
(mg/L)
Copper, total1.0

(3) [Reserved]

(4)(i) Cooling tower blowdown. The pollutants discharged in cooling tower blowdown shall not exceed the concentration listed in the following table:

Pollutant or pollutant propertyPSNS
Maximum for any time
(mg/L)
The 126 priority pollutants (appendix A) contained in chemicals added for cooling tower maintenance, except:(1)
Chromium, total0.2
zinc, total1.0

1No detectable amount.

(ii) 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)(4)(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.

(5) 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.

(6) 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 propertyPSNS
Maximum for
any 1 day
Average of daily
values for 30
consecutive days
shall not exceed
Arsenic, total (µg/L)4
Mercury, total (ng/L)3924
Selenium, total (µg/L)5
TDS (mg/L)5024

(7) 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.

(8) 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.

(9) 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 propertyPSNS
Maximum for
any 1 day
Average of daily
values for 30
consecutive days
shall not exceed
Arsenic, total (µg/L)4
Mercury, total (ng/L)1.81.3
Selenium, total (µg/L)453227
Total dissolved solids (mg/L)3822

(10) 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 propertyPSNS
Maximum for
any 1 day
Average of daily
values for 30
consecutive days
shall not exceed
Arsenic, total (µg/L)118
Mercury, total (ng/L)788356

[80 FR 67902, Nov. 3, 2015]

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Appendix A to Part 423—126 Priority Pollutants

001   Acenaphthene

002   Acrolein

003   Acrylonitrile

004   Benzene

005   Benzidine

006   Carbon tetrachloride (tetrachloromethane)

007   Chlorobenzene

008   1,2,4-trichlorobenzene

009   Hexachlorobenzene

010   1,2-dichloroethane

011   1,1,1-trichloreothane

012   Hexachloroethane

013   1,1-dichloroethane

014   1,1,2-trichloroethane

015   1,1,2,2-tetrachloroethane

016   Chloroethane

018   Bis(2-chloroethyl) ether

019   2-chloroethyl vinyl ether (mixed)

020   2-chloronaphthalene

021   2,4, 6-trichlorophenol

022   Parachlorometa cresol

023   Chloroform (trichloromethane)

024   2-chlorophenol

025   1,2-dichlorobenzene

026   1,3-dichlorobenzene

027   1,4-dichlorobenzene

028   3,3-dichlorobenzidine

029   1,1-dichloroethylene

030   1,2-trans-dichloroethylene

031   2,4-dichlorophenol

032   1,2-dichloropropane

033   1,2-dichloropropylene (1,3-dichloropropene)

034   2,4-dimethylphenol

035   2,4-dinitrotoluene

036   2,6-dinitrotoluene

037   1,2-diphenylhydrazine

038   Ethylbenzene

039   Fluoranthene

040   4-chlorophenyl phenyl ether

041   4-bromophenyl phenyl ether

042   Bis(2-chloroisopropyl) ether

043   Bis(2-chloroethoxy) methane

044   Methylene chloride (dichloromethane)

045   Methyl chloride (dichloromethane)

046   Methyl bromide (bromomethane)

047   Bromoform (tribromomethane)

048   Dichlorobromomethane

051   Chlorodibromomethane

052   Hexachlorobutadiene

053   Hexachloromyclopentadiene

054   Isophorone

055   Naphthalene

056   Nitrobenzene

057   2-nitrophenol

058   4-nitrophenol

059   2,4-dinitrophenol

060   4,6-dinitro-o-cresol

061   N-nitrosodimethylamine

062   N-nitrosodiphenylamine

063   N-nitrosodi-n-propylamin

064   Pentachlorophenol

065   Phenol

066   Bis(2-ethylhexyl) phthalate

067   Butyl benzyl phthalate

068   Di-N-Butyl Phthalate

069   Di-n-octyl phthalate

070   Diethyl Phthalate

071   Dimethyl phthalate

072   1,2-benzanthracene (benzo(a) anthracene

073   Benzo(a)pyrene (3,4-benzo-pyrene)

074   3,4-Benzofluoranthene (benzo(b) fluoranthene)

075   11,12-benzofluoranthene (benzo(b) fluoranthene)

076   Chrysene

077   Acenaphthylene

078   Anthracene

079   1,12-benzoperylene (benzo(ghi) perylene)

080   Fluorene

081   Phenanthrene

082   1,2,5,6-dibenzanthracene (dibenzo(,h) anthracene)

083   Indeno (,1,2,3-cd) pyrene (2,3-o-pheynylene pyrene)

084   Pyrene

085   Tetrachloroethylene

086   Toluene

087   Trichloroethylene

088   Vinyl chloride (chloroethylene)

089   Aldrin

090   Dieldrin

091   Chlordane (technical mixture and metabolites)

092   4,4-DDT

093   4,4-DDE (p,p-DDX)

094   4,4-DDD (p,p-TDE)

095   Alpha-endosulfan

096   Beta-endosulfan

097   Endosulfan sulfate

098   Endrin

099   Endrin aldehyde

100   Heptachlor

101   Heptachlor epoxide (BHC-hexachlorocyclohexane)

102   Alpha-BHC

103   Beta-BHC

104   Gamma-BHC (lindane)

105   Delta-BHC (PCB-polychlorinated biphenyls)

106   PCB-1242 (Arochlor 1242)

107   PCB-1254 (Arochlor 1254)

108   PCB-1221 (Arochlor 1221)

109   PCB-1232 (Arochlor 1232)

110   PCB-1248 (Arochlor 1248)

111   PCB-1260 (Arochlor 1260)

112   PCB-1016 (Arochlor 1016)

113   Toxaphene

114   Antimony

115   Arsenic

116   Asbestos

117   Beryllium

118   Cadmium

119   Chromium

120   Copper

121   Cyanide, Total

122   Lead

123   Mercury

124   Nickel

125   Selenium

126   Silver

127   Thallium

126   Silver

128   Zinc

129   2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD)

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