NSPS OOOO and OOOOa Proposed Rule Making
August 31, 2015

On August 18, 2015, the EPA proposed new regulations aimed at reducing methane (CH4) and VOC emissions from the oil and gas (O&G) sector. The proposals are a part of the President’s Climate Action Plan to cut CH4 emissions from the O&G sector by 40 to 45 percent from 2012 levels by 2025.

The proposed rules amend 40 CFR 60 Subpart OOOO with updates/clarifications and include CH4 (along with VOCs) as a regulated pollutant covered by NSPS OOOO. There are no changes to the current list of NSPS OOOO affected emission sources.

The proposal also creates a new 40 CFR 60 Subpart OOOOa. In these rules, the EPA proposes to regulate CH4 and VOCs from the O&G sources already regulated in the current Subpart OOOO regulations and regulates additional emission sources not covered by the current regulations. 

The EPA will take comment on the proposed rules for 60 days after they are published in the Federal Register. Expect promulgation of the final rules in early 2016.




Affected Sources for NSPS OOOOa

Sources affected by the proposed OOOOa regulations include:

  • Completions of hydraulically wells at gas and oil wells (oil wells not in current regulation)
  • Compressors
  • Fugitive equipment leaks
  • Pneumatic controllers
  • Pneumatic pumps (not in current Subpart OOOO)
  • Storage tanks


Effective Dates


The proposed new rule will be known as 40 CFR 60 Subpart OOOOa.  This proposed rule would not affect facilities constructed prior to the proposal date of the new Subpart OOOO rules in the Federal Register. We expect the rule to be published in the Federal Register in September 2015.


NSPS OOOO (the current rule) applies to facilities constructed, modified or reconstructed after August 23, 2011, (i.e., original proposal date of Subpart OOOO) and before the date of publication of the Subparts OOOO/OOOOa proposal in the Federal Register.

Except for updates/clarifications and setting CH4 standards, the proposed amendments to the current Subpart OOOO do not change the requirements for operations already covered by the current Subpart OOOO standards. Also, facilities constructed prior to August 13, 2011 (and not modified or reconstructed) will not be affected by the proposed rules.


Summary of Proposed NSPS OOOOa Emission Sources and Standards

The following summarizes the emission sources covered by the proposed NSPS OOOOa.

Completions of hydraulically wells at gas and oil wells – the proposed rule has similar requirements as the current Subpart OOOO for reduced emissions completions (RECs) for both affected oil wells and gas wells that are hydraulically fractured or refractured. 

Reciprocating and Centrifugal Compressors – the proposed rule has similar requirements as the current Subpart OOOO regulations for replacement or control of rod packing seals for reciprocating compressors and control of venting from centrifugal compressors. The proposed rule exempts compressors operating at oil and gas well sites.

Fugitive Equipment Leaks – the proposal will require leak detection and repair (LDAR) program for valves, connectors, pressure relief devices, open-ended lines, access doors, flanges, closed vent systems, thief hatches, agitator seals, distance pieces, crankcase vents, blowdown vents, pump seals or diaphragms, compressors, separators, pressure vessels, dehydrators, heaters, instruments, and meters.

The proposed rule will require an initial and periodic leak detection surveys using optical gas imaging (OGI), repair of leaks, a written corporate-wide fugitive emissions monitoring plan. Periodic leak detection is semiannual and can change to quarterly if have 2 consecutive semiannual monitoring surveys with fugitive emissions detected at greater than 3.0% of the fugitive emissions components at a well site.

Subpart OOOOa would add the following facility types to the LDAR requirement:         

  • Oil and gas well sites
  • Production gathering and boosting stations
  • Natural gas processing facilities
  • Natural gas compressor stations.

The following exemptions are proposed for LDAR program:

  • Exempts a well site that only contains one or more wellheads.
  • Exempts low production well sites with an average combined oil and natural gas production for the wells at the site being less than 15 barrels of oil equivalent (boe) per day averaged over the first 30 days of production).

The proposed rule seeks comments on the need for third-party audits and/or self-auditing for LDAR programs.

Pneumatic controllers – the proposed rule has similar emission standards as the current Subpart OOOO. O&G well sites, production gathering/boosting stations and natural gas compressor stations (transmission & storage) continuous, low-bleed devices using natural gas would be required that have a bleed rate of less than or equal to 6 standard cubic feet per hour (scfh).

For natural gas processing plants, continuous, low-bleed devices must have a bleed rate of 0 scfh.

Pneumatic pumps – the proposed rule requires each pneumatic pump affected facility at a natural gas processing plant to have a natural gas emission rate of zero (e.g., use compressed air).

Pneumatic pumps affected facility at a location other than a natural gas processing plant must reduce natural gas emissions by 95.0 percent but is exempt from this requirement if there is no existing emission control device (e.g, VRU, enclosed combustor) to control the vent gas. The proposed rule does not require a facility to install a control device solely for the purposes of complying with the 95.0 percent reduction. If an emission control device is subsequently installed at the facility after an uncontrolled pneumatic pump is installed, the vent gas must be routed to the control device.

Storage tanks – the proposed rule has similar requirements as the current Subpart OOOO for storage tanks. Storage tanks that emit 6 or more tons per year (tpy) of VOC must use a control device that reduces VOC emissions by at least 95%. Typical control devices include VRUs and enclosed combustors

Next Generation Compliance and Rule Effectiveness

EPA is seeking comments on the following approaches to ensure compliance with Subparts OOOO and OOOOa:

  • Independent third-party verification that may include Professional Engineer certification of closed vent system and control device design and installation.
  • Independent third-party verification of fugitives emissions monitoring program
  • Third-party information reporting of manufacturer tested combustors
  • Electronic reporting and transparency

To review a table from USEPA that summarizes changes to the emission source types and O&G sectors affected see: http://www.epa.gov/airquality/oilandgas/pdfs/og_table_081815.pdf


Get Prepared and Stay in Compliance

HY-BON can help your company prepare and comply with the existing NSPS requirements and help you prepare for the upcoming changes.

Our IQR (Identify, Quantify and Rectify) services can help you know your facility VOC and CH4 emissions.  Using our IQR services and our ongoing Vent Gas Management (VGM) system we can help you reduce GHG and VOC emissions and stay in compliance with NSPS OOOO and state air permits. This can make your company money. HY-BON’s vent gas management (VGM) system is a cost effective way to take this issue off of your plate. We use “best in class” vapor recovery units (VRU), Vapor Recovery Towers (VRT) and enclosed combustors (ECU) to comply with storage tank emission control requirements.  

Contact us today {#?9Vq=-_ujX]#[09LEg#P5l'~e and {#?9Vq=-_ujXNI&B]#[og'yJ.}%gXZGW&s+.