Federal Clean Air Act

This section includes links to the Clean Air Act and associated regulations, guidelines, and policies pertinent to oil and gas surface operations.

Clean Air Act

The Clean Air Act (42 U.S.C. § 7401 et seq.) governs air quality in the United States.  The United States Environmental Protection Agency (EPA) is the federal agency responsible for creating and enforcing national air quality regulations under the Clean Air Act.   Each state and Indian tribe may develop its own program for enforcing Clean Air Act requirements.  EPA air quality regulations can be found in Parts 50-99 of Title 40 of the Code of Federal Regulations and on the EPA website.  

Congress passed the CAA (42 U.S.C. 85) in 1970 in order to combat air pollution in the United States and protect the health and general welfare of United States citizens against air pollutants. The act prescribes the measures that federal agencies, state and local governments, and polluters in business and industry must take in order to decrease air pollution in the country. The act was last amended in 1990.

Specifically, under the CAA, air pollution prevention (that is, the reduction or elimination, through any measures, of the amount of pollutants produced or created at the source) and air pollution control at its source is the primary responsibility of States and  local governments.  42 U.S.C. § 7401(a)(3) (2006). The Act's purpose is to "protect and enhance the quality of the Nation’s air resources so as to promote the public health and welfare and the productive capacity of its population." 42 U.S.C. § 7401(b)(1) (2006).

Provisions of the CAA particularly relevant to oil and gas development are:

42 U.S.C. §§ 7408-10 (2006) – National Primary and Secondary Ambient Air Quality Standards – The purpose of national ambient air quality standards (NAAQS) is to limit the emission of substances that contribute to air pollution and endanger public health.  § 7409(a)-(b). The CAA does not enumerate the substances to be regulated by NAAQS, but rather gives the Environmental Protection Agency (EPA) the authority to determine which substances should be governed by NAAQS. § 7408(a)(1).  Each state must, in turn, adopt and submit to the EPA for approval a state implementation plan (SIP) for each primary and secondary standard that provides for the implementation, maintenance, and enforcement of such standards. § 7410(a)(1).

42 U.S.C. § 7411 (2006) – Standards of Performance for New Stationary Sources – The purpose of standards of performance for new stationary sources, or new source performance standards (NSPS), is to regulate buildings, structures, facilities, and installations that emit any air pollutant, and which were built after the promulgation of regulations under the CAA.  § 7411(a).  Like NAAQS, NSPS are enforced by each state through an SIP, unless the EPA itself chooses to enforce them.  §7411(c). In addition, the EPA determines which units constitute "stationary sources" for purposes of the CAA. § 7411(b). Some existing stationary. Sources are also regulated by the CAA. § 7411(d).

42 U.S.C. § 7412 (2006) – Hazardous Air Pollutants – The CAA requires the EPA to establish and enforce National Emission Standards for Hazardous Air Pollutants (NESHAPS).  These standards regulate 188 different hazardous air pollutants (HAP). See § 7412(b). The CAA further directs the EPA to name major and area sources that emit these HAPs, and develop regulations for these sources based on maximum achievable control technology (MACT). §§ 7412(a), (c), (g).

42 U.S.C. § 7412(n)(4) (2006) – Section 7412(n)(4)(A) provides that emissions from oil and gas wells, pipeline compressors, and pump stations cannot be aggregated with emissions from other similar units to determine whether such units or stations are major sources of air pollution.  For oil and gas wells, emissions cannot be aggregated for any other purpose under Section 7412, either.  Section 7412(n)(4)(B) provides that the EPA may only establish an "area source" category for oil and gas production wells if they are located in a metropolitan statistical area or consolidated metropolitan statistical area with over a million people if such wells present "more than a negligible risk of adverse effects to public health." 42 U.S.C. § 7412(c)(3) (2006). 

42 U.S.C. § 7473(c)(1)(A)-(B) (2006) – Sub-Section A makes an exception to national ambient air quality standards (NAAQS) for emissions from stationary sources which have converted from the use of petroleum products or natural gas by reason of an order in effect under the provisions of 15 U.S.C. § 792(a) and (b). Sub-Section B makes an exception to NAAQS for emissions from stationary sources which have converted from the use of natural gas because of a natural gas curtailment made pursuant to the Federal Power Act, 16 U.S.C. § 791(a).

42 U.S.C. § 7479(3) – Defines “best available control technology” as an emission limitation based on the maximum degree of reduction of each pollutant from any major emitting facility which the permitting authority determines is achievable through production processes and available methods, systems, and techniques. However, application of “best available control technology” cannot result in emissions of any pollutants exceeding the emissions allowed under standards established pursuant to section 7411 or 7422 of the Clean Air Act.

42 U.S.C. §§ 7651-7651o (Title IV-A) (2006) – Acid Deposition Control – Title IV-A deals with acid deposition control, and is often known as the "acid rain program," because it aims to reduce the effects of acid deposition through precipitation by greatly reducing sulfur dioxide and nitrogen dioxide emissions. § 7651.

42 U.S.C. § 7661-7661f (Title V) (2006) – Permits – Title V establishes the permit program for regulations promulgated under the CAA, for both states and the federal government.  In general, states enforce these regulations with the approval of the EPA, but sometimes the EPA itself enforces them.

Clean Air Act Regulations for Oil and Gas

Title 40 of the federal regulations deals with environmental protection, and all of the air quality regulations promulgated under the CAA, which are contained in Chapter I, sections 50 through 99 of Title 40, are enforceable solely by the Environmental Protection Agency (EPA). (But see the "State Operating Permit Programs" section below.)

National Primary and Secondary Ambient Air Quality Standards (40 C.F.R. pt. 50 (2015)) – The EPA establishes national primary and secondary ambient air quality standards to regulate pollution in the United States. "National primary ambient air quality standards define levels of air quality which the Administrator judges are necessary, with an adequate margin of safety, to protect the public health," while "[n]ational secondary ambient air quality standards define levels of air quality which the Administrator judges necessary to protect the public welfare from any known or anticipated adverse effects of a pollutant," pt. 50.2. The goal of national ambient air quality standards (NAAQS) is to limit levels of "criteria pollutants" like carbon monoxide, sulfur dioxide, lead, nitrogen dioxide, particulate matter, and ozone. Under section 110 of the CAA, each state must develop a State Implementation Plan (SIP) to identify sources of air pollution and reduce air pollution to meet federal standards.

Regulations of interest for the oil and gas industry include:

40 C.F.R. pt. 50.4 – Primary NAAQS for Sulfur Oxides (Sulfur Dioxide) – This part establishes the maximum allowable concentration of sulfur dioxide in the atmosphere in a calendar year, and in any single 24-hour period, which may not be exceeded more than once during any calendar year.

40 C.F.R. pt. 50.5 – Secondary NAAQS for Sulfur Oxides (Sulfur Dioxide) – This part establishes the maximum allowable concentration of sulfur dioxide in the atmosphere during any three-hour period, which may not be exceeded more than once during any calendar year.

40 C.F.R. pt. 50.6 – Primary and Secondary NAAQS for Particulate Matter (PM) 10 (particles with an aerodynamic diameter less than or equal to a nominal 10 micrometers) – This part establishes the maximum allowable concentration of PM 10 in the atmosphere in a calendar year, and in any single 24-hour period, which may not be exceeded more than once during any calendar year.

40 C.F.R. pt. 50.7 – Primary and Secondary NAAQS for PM 2.5 (particles with an aerodynamic diameter less than or equal to a nominal 2.5 micrometers) – This part establishes the maximum allowable concentration of PM 2.5 in the atmosphere in a calendar year, and in any single 24-hour period, which may not be exceeded more than once during any calendar year.

40 C.F.R. pt. 50.8 – Primary NAAQS for Carbon Monoxide – This part establishes the maximum allowable concentration of carbon monoxide in the atmosphere during any given 8-hour period and during any given 1-hour period, neither of which may be exceeded more than once during any calendar year.

40 C.F.R. pt. 50.9 – 1-hour Primary and Secondary NAAQS for Ozone – This part establishes the maximum allowable concentrate of ozone in the atmosphere during any given 1-hour period, which may not be exceeded more than once during any calendar year.

40 C.F.R. pt. 50.10 – 8-hour Primary and Secondary NAAQS for Ozone – This part establishes the maximum allowable concentrate of ozone in the atmosphere during any given 8-hour period, which may not be exceeded more than once during any calendar year.

40 C.F.R. pt. 50.11 – Primary and Secondary NAAQS for Nitrogen Oxide – This part establishes the maximum allowable concentration of nitrogen oxide in the atmosphere during any calendar year.

Standards of Performance for New Stationary Sources (40 C.F.R. pt. 60 (2015)), Subpart OOOO—Standards for Crude Oil and Natural Gas Production, Transmission and Distribution (40 C.F.R. pts. 60.5360-.5499 (Subpart OOOO)) – This subpart, modified in a 2012 rulemaking, establishes emission standards and compliance schedules for the control of volatile organic compounds (VOC) and sulfur dioxide (SO2) emissions from affected facilities that commence construction, modification or reconstruction after August 23, 2011. In late 2015, EPA proposed to amend the new source performance standards (NSPS) again to cut methane and VOC emissions from the oil and natural gas industry. The main sources of emissions being considered in the rulemaking are compressors, pneumatic controllers, pneumatic pumps, hydraulically fractured oil well completions, and fugitive emissions from well sites and compressor stations.

40 C.F.R. pts. 60.5360-.5499 (Subpart OOOO) – Standards of Performance for Crude Oil and Natural Gas Production, Transmission and Distribution – This subpart establishes emission standards and compliance schedules for the control of volatile organic compounds (VOC) and sulfur dioxide (SO2) emissions from affected facilities that commence construction, modification or reconstruction after August 23, 2011.

In late 2015, EPA proposed to amend the new source performance standards (NSPS) to cut methane and VOC emissions from the oil and natural gas industry. The main sources of emissions being considered in the rulemaking are compressors, pneumatic controllers, pneumatic pumps, hydraulically fractured oil well completions, and fugitive emissions from well sites and compressor stations.

National Emission Standards for Hazardous Air Pollutants for Source Categories (40 C.F.R. pt. 63 (2015)) – The EPA establishes national emission standards for hazardous air pollutants (NESHAP) for "specific categories of stationary sources that emit (or have the potential to emit) one or more hazardous air pollutants listed in [part 63] pursuant to section 112(b) of the [Clean Air] Act." 40 C.F.R. pt. 63.1(a)(2) (2007). Major sources and areas sources, the two categories of sources regulation by Title 40, are defined in pt. 63.2. Emissions from oil and gas production and exploration wells cannot be aggregated with emissions from similar units to determine whether such emission points or stations are major sources.

Regulations of interest for the oil and gas industry include:

40 C.F.R. pts. 63.160-.183 (Subpart H) – National Emission Standards for Organic Hazardous Air Pollutants for Equipment Leaks – These provisions apply to pumps, compressors, agitators, pressure relief devices, and other pieces of equipment that are intended to operate in organic hazardous air pollutant service 300 hours or more per year within a source subject to part 63 that references subpart H.  Pt. 63.160(a). 

40 C.F.R. pts. 63.760-.777 (Subpart HH) – National Emission Standards for Hazardous Air Pollutants from Oil and Natural Gas Production Facilities – These provisions apply to emission points of hazardous air pollutants located at oil and natural gas production facilities that are major or area sources of hazardous air pollutants (i.e., all sources of hazardous air pollutants), as well as "[f]acilities that process, upgrade, or store hydrocarbon liquids prior to the point of custody transfer," and "[f]acilities that process, upgrade, or store natural gas prior to the point at which natural gas enters the natural gas transmission and storage source category or is delivered to a final end user." Pt. 63.760(a)(1)-(3). For major sources, all glycol dehydration units; storage vessels with the potential for flash emissions; and all ancillary equipment used in volatile hazardous air pollutant service also constitute affected sources. Pt. 63.760(b)(1). For area sources, triethylene glycol dehydration units that meet the criteria of pt. 63.760(a) also constitute affected sources.  Pt. 63.760(b)(2). 

40 C.F.R. pts. 63.1100-.1114 (Subpart YY) – National Emission Standards for Hazardous Air Pollutants for Source Categories: Generic Maximum Achievable Control Technology (MACT) Standards – Subpart YY applies MACT standards to eight different source categories and affected sources, including ethylene production emission points located at major sources.

40 C.F.R. pts. 63.6080-.6175 (Subpart YYYY) – National Emission Standards for Hazardous Air Pollutants for Stationary Combustion Turbines – This subpart applies to stationary combustion turbines located at major sources of hazardous air pollutant emissions, including turbines located at oil and gas production facilities. Pt. 63.6085(a)-(b).

40 C.F.R. pts. 63.6580-.6675 (Subpart ZZZZ) – National Emissions Standards for Hazardous Air Pollutants for Stationary Reciprocating Internal Combustion Engines (RICE) – This subpart applies to RICE located at major sources of hazardous air pollutant emissions, including oil and gas production facilities. Pt. 63.6585(a)-(b).

State Operating Permit Programs (40 C.F.R. pt. 70 (2015)) – Each state and Indian tribe must establish a comprehensive air quality permitting system consistent with CAA Title V, in accordance with EPA regulations and with the approval of the EPA. Pt. 70.1(a). Part 70 defines the minimum requirements that each state must meet for its program, as well as the standards that the EPA uses in approving individual state programs. Pt. 70.1(a). Individual states may establish more stringent requirements that are not inconsistent with the act, but they may not establish less stringent requirements than the CAA or EPA regulations. Pt. 70.1(c). States and Indian tribes with an approved program are responsible for regulating the oil and gas industry within their jurisdictions.

Federal Operating Permit Programs (40 C.F.R. pt. 71 (2015)) – If any state or Indian tribe does not have an operating program that has been approved in full by the EPA, that state will then be subject to the federal permit program under Part 71, in either the whole state or those parts of the state not regulated by the state permit program. Pt. 71.1(a)-(b).

Clean Air Act Oil and Gas Guidance

Profile of the Oil and Gas Extraction Industry -- The profile is published by the EPA Office of Compliance as part of its Sector Notebook project. The profile provides an introduction to the oil and gas extraction industry, its waste streams, pollution prevention opportunities, compliance and enforcement history, compliance assurance activities and initiatives, and a summary of pertinent statutes and regulations.