Changes to Air Emissions Standards in Store for the Oil and Natural Gas Sector Including Cuts to Methane Emissions

By: Amy Bauer

MethaneThe oil and natural gas (O&G) sector is facing increased scrutiny from the United States Environmental Protection Agency (USEPA). Recently, the agency unveiled proposed regulations to reduce greenhouse gas emissions (GHG). Federal regulations already regulate volatile organic compounds (VOCs) and sulfur dioxide emissions, and the proposed regulations would will include methane emissions and expand requirements affecting VOC emissions. The Obama administration’s goal is to cut methane emissions from the Sector by 40 to 45 percent by 2025. Multiple source categories are affected – production, processing, transmissions, and storage; however, the primary focus is on new and modified sources, not existing sources.

In 2012, USEPA finalized the New Source Performance Standard (NSPS) for new and modified O&G sources, regulating emissions from hydraulically fractured gas wells. The proposed rule amends the NSPS by adding requirements for methane. Additionally, it mandates the use or reduced emissions completion (REC) or green completions to hydraulically fractured oil wells. The proposed rule includes new requirements to control VOCs and methane emissions from pneumatic pumps used from well sites to compressor stations, and also addresses VOC/methane leaks.

The following is a brief summary of affected sources and the proposed standards:

  • Compressors. Ninety five percent reduction of methane and VOC emissions from wet seal centrifugal compressors across the source category, except for those located at well sites.
  • Pneumatic controllers. Natural gas bleed rate limit of 6 standard cubic feet per hour (scfh) to reduce methane and VOC emissions from individual, continuous bleed, natural gas-driven pneumatic controllers at locations across the source category other than natural gas processing plants. The bleed rate remains zero at natural gas processing plants.
  • Pneumatic pumps.  At locations other than natural gas processing plants, methane and VOC emissions from natural gas-driven chemical/methanol pumps and diaphragm pumps be reduced by 95 percent if a control device is already available on-site. At natural gas processing plants, the proposed standards would require the methane and VOC emissions from natural gas-driven chemical/methanol pumps and diaphragm pumps to be zero.
  • Hydraulically fractured oil well completions. Owners and/or operators use green completions (reduced emissions completions) to separate natural gas well flowback; gas can then be treated and reused or sold.
  • Fugitive emissions from well sites and compressor stations. New and modified well sites and compressor stations (which include the transmission and storage segment and the gathering and boosting segment) conduct fugitive emissions surveys semiannually with optical gas imaging (OGI) technology and repair the sources of fugitive emissions within 15 days that are found during those surveys.

In addition to the proposed NSPS, the USEPA:

  • Proposed draft guidelines to assist states in reducing VOC emissions from existing O&G sources in certain ozone nonattainment areas as well as in the mid-Atlantic and northeastern states in the Ozone Transport Region.
  • Proposed options for clarifying the Agency’s air-permitting rules as they apply to the oil and natural gas industry. The USEPA uses three key factors to determine whether a source needs a permit and the type of permit required. The factors are whether equipment and activities are:
    • In the same industrial grouping (defined by standard industrial classification code, or “SIC code”)
    • Under the control of the same person/people
    • Located on contiguous or adjacent properties.
  • Proposing a federal implementation plan (FIP) to implement the federal minor New Source Review program in Indian country for O&G production.

On July 31, 2015, the USEPA finalized two updates to the 2012 NSPS for the O&G industry. The Agency revised its definitions of low-pressure gas well and storage vessel as defined in the August 2012 NSPS for VOC emissions from gas wells. In both cases, industry requested that the definitions be changed. Regarding low-pressure gas well, USEPA has decided to basically adhere to its own definition and not adopt industry’s recommended definition, only adding a single word—changing “vertical depth” to “true vertical depth.” To address industry concerns, for storage vessel, USEPA has amended the definition to remove “storage vessels connected or installed in parallel.”


EHS Support’s team of environmental professionals has multi-continental experience with regulatory and technical issues facing the O&G industry. For compliance assistance related to O&G sector, please contact Amy Bauer or Chris Pratt (International Resources).

Amy. Bauer has 15 years of experience conducting and managing environmental site assessments, regulatory compliance audits, environmental investigations, and regulatory compliance support…. Read More



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