2018-04373. Review of Existing VOC Emissions Factor for Flares at Natural Gas Production Sites and New Emissions Factors for Enclosed Ground Flares

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice of final action.

SUMMARY:

On February 5, 2018, the Environmental Protection Agency (EPA) took final action on its review of the existing volatile organic compounds (VOC) emissions factor for flares at natural gas production sites pursuant to section 130 of the Clean Air Act (CAA). While the review did not result in a revision to this existing VOC emissions factor, the EPA issued new total hydrocarbon (THC) emissions factors for enclosed ground flares based on the available flare data.

DATES:

Applicable on March 5, 2018.

ADDRESSES:

You may view this final action and the supporting information electronically at: https://www.epa.gov/​air-emissions-factors-and-quantification/​new-emissions-factors-enclosed-ground-flares.

FOR FURTHER INFORMATION CONTACT:

Ms. Gerri Garwood, Measurement Policy Group (MPG), Sector Policies and Programs Division (D243-05), Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, telephone number: [phone]; fax number: [phone]; and email address: [e-mail].

SUPPLEMENTARY INFORMATION:

On February 5, 2018, the EPA finalized its review of the existing VOC emissions factor for flares at natural gas production sites pursuant to its obligation under CAA section 130 to review, and, if necessary, revise emissions factors for certain pollutants, including VOC, at least every 3 years.

We evaluated test data available to the Agency for flares at natural gas production sites, data from testing conducted by manufacturers under 40 CFR part 60, subparts OOOO and OOOOa and 40 CFR part 63, subpart HH and HHH, and information submitted during the public comment period. The available flare data pertained to THC emissions and did not provide sufficient information for estimating VOC emissions from the tested flares. As such, the available data gave no indication that the existing VOC emissions factor for flares at natural gas production sites is somehow flawed or outdated and, thus, warrants revision. Therefore, our review did not result in a revision to this VOC emissions factor.

While we have not revised the existing VOC emissions factor, we did use the available THC emissions data for enclosed ground flares to develop six new THC emissions factors for enclosed ground flares. The six emissions factors are finalized as an update to Section 13.5 of AP-42, Compilation of Air Pollutant Emission Factors. AP-42 is the primary compilation of EPA's emissions factor information. We have also clarified the heating value basis for the emissions factors in AP-42 Tables 13.5-1 through 13.5-3 in order to allow users to generate more accurate emissions estimates and clarified that the emissions factors in the tables represent the emissions at the exit of a flare, not the uncontrolled VOC or THC emissions routed to the flare.

The final actions described above were issued on February 5, 2018. Our review and analysis of the data are documented in a report titled “Review and Analysis of Emissions Test Reports for Purposes of Reviewing the Natural Gas Production Flares Volatile Organic Compounds Emissions Factor Under Clean Air Act Section 130.” Prior to taking final action, the EPA issued a proposal on its AP-42 website on June 5, 2017, and solicited comment on the proposal. The EPA responded to the comments received during the public comment period in a memorandum titled “Summary of EPA Responses to Public Comments Received on the Proposed Emissions Factors for Enclosed Ground Flares at Natural Gas Production Sites and Chemical Manufacturing Processes.” These documents, along with a link to the updated section in AP-42, were posted on the website listed in the ADDRESSES section of this notice on February 5, 2018.

These actions constitute final agency action of national applicability for purposes of section 307(b)(1) of the CAA. Pursuant to CAA section 307(b)(1), judicial review of these final agency actions may be sought only in the United States Court of Appeals for the District of Columbia Circuit. Petitions for review must be filed by May 4, 2018. Judicial review of these final agency actions may not be obtained in subsequent proceedings, pursuant to CAA section 307(b)(2). These actions are not a rulemaking and are not subject to the various statutory and other provisions applicable to a rulemaking.

Dated: February 26, 2018.

Panagiotis E. Tsirigotis,

Director, Office of Air Quality Planning and Standards.