Oil and Natural Gas Sector: National Emission Standards for Hazardous Air Pollutants

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Request for information.

SUMMARY:

This action requests information related to hazardous air pollutant (HAP) emissions from sources in the oil and natural gas production and natural gas transmission and storage segments of the oil and natural gas sector. In 2012, the Environmental Protection Agency (EPA) revised the National Emission Standards for Hazardous Air Pollutants (NESHAP) for the Oil and Natural Gas Production Facilities and the Natural Gas Transmission and Storage Facilities major source categories. This action requests additional data and information that was not available at that time. In particular, we are requesting data on storage vessels without potential flash emissions (PFE) and data on HAP emissions from regulated small glycol dehydrators. With regard to the small glycol dehydrators we are particularly interested in data regarding any emissions of HAP other than benzene, toluene, ethylbenzene, and xylene (BTEX), information on available control options for any such HAP and information regarding a potential compliance demonstration issue with respect to the 2012 standards for small glycol dehydration units, as they apply to units with very low emissions.

DATES:

Comments must be received on or before January 26, 2016.

ADDRESSES:

Submit your comments, identified by Docket ID No. EPA-HQ-OAR-2015-0747, to the Federal eRulemaking Portal: http://www.regulations.gov. Follow the online instructions for submitting comments. Once submitted, comments cannot be edited or withdrawn. The EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. The EPA will generally not consider comments or comment contents located outside of the primary submission (i.e., on the web, cloud, or other file sharing system). For additional submission methods, the full EPA public comment policy, information about CBI or multimedia submissions, and general guidance on making effective comments, please visit http://www2.epa.gov/dockets/commenting-epa-dockets.

Docket. All documents in the docket are listed in the http://www.regulations.gov index. Although listed in the index, some information is not publicly available, e.g., CBI or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, will be publicly available only in hard copy. Publicly available docket materials are available either electronically at http://www.regulations.gov or in hard copy at the U.S. Environmental Protection Agency, EPA Docket Center, EPA WJC West Building, Room 3334, 1301 Constitution Ave. NW., Washington, DC. The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is (202) 566-1744, and the telephone number for the Air Docket is (202) 566-1742.

FOR FURTHER INFORMATION CONTACT:

For further information about this action, contact Mr. Matthew Witosky, Sector Policies and Programs Division (E143-05), Office of Air Quality Planning and Standards, Environmental Protection Agency, Research Triangle Park, North Carolina 27711, telephone number: (919) 541-2865; facsimile number: (919) 541-3740; email address: witosky.matthew@epa.gov. For further information on the EPA's oil and natural gas sector regulatory program, contact Mr. Bruce Moore, Sector Policies and Programs Division (E143-05), Office of Air Quality Planning and Standards, Environmental Protection Agency, Research Triangle Park, North Carolina 27711, telephone number: (919) 541-5460; facsimile number: (919) 541-3470; email address: moore.bruce@epa.gov. For additional contact information, see the following SUPPLEMENTARY INFORMATION section.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this action apply to me?

Categories and entities potentially affected by this action include:

This table is not intended to be exhaustive, but rather is meant to provide a guide for readers regarding entities likely to be affected by this action. If you have any questions regarding the applicability of this action to a particular entity, consult either the air permitting authority for the entity or your EPA Regional representative as listed in 40 CFR 60.4 or 40 CFR 63.13 (General Provisions).

B. What should I consider as I prepare my information/comments to the EPA?

Do not submit information containing CBI to the EPA through www.regulations.gov or email. Send or deliver information identified as CBI only to the following address: OAQPS Document Control Officer (C404-02), Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, Attention: Docket ID No. EPA-HQ-OAR-2015-0747. Clearly mark the part or all of the information that you claim to be CBI. For CBI in a disk or CD-ROM that you mail to the EPA, mark the outside of the disk or CD-ROM as CBI and then identify electronically within the disk or CD-ROM the specific information that is claimed as CBI. In addition to one complete version of the comment that includes information claimed as CBI, a copy of the comment that does not contain the information claimed as CBI must be submitted for inclusion in the public docket. Information so marked will not be disclosed except in accordance with procedures set forth in 40 CFR part 2.

II. Background

In 2012, the EPA issued a final rule titled “Oil and Natural Gas Sector: New Source Performance Standards and National Emission Standards for Hazardous Air Pollutants Reviews,” 77 FR 49490 (August 16, 2012). The final rule contains final actions on two different national standards for the oil and natural gas industry promulgated by the EPA under the Clean Air Act (CAA): (1) The new source performance standards (NSPS), promulgated under section 111 of the CAA, and (2) the NESHAP, promulgated under section 112 of the CAA. The NESHAP portion of the final rule (“the 2012 NESHAP revisions”) included the EPA's residual risk and technology review of the NESHAP for the Oil and Natural Gas Production Facilities and the NESHAP for the Natural Gas Transmission and Storage Facilities major source categories (40 CFR part 63 subpart HH and HHH, respectively) pursuant to sections 112(f)(2) and (d)(6) of the CAA. In addition, pursuant to section 112(d)(2) and (3) of the CAA, the EPA established emission standards for BTEX based on maximum achievable control technology (MACT) for a subcategory of glycol dehydrators referred to as the “small glycol dehydration units.”

This request is to obtain additional data and information. We are interested in receiving information on HAP emissions from some affected facilities in the oil and natural gas production, and the natural gas transmission and storage segments of the oil and natural gas sector. In particular, the EPA is interested in the following information:

1. HAP emissions from storage vessels without PFE from the oil and natural gas production segment;

2. Emission information on HAP other than BTEX from small glycol dehydrators and available control options.

In addition, the EPA recently learned of a potential compliance demonstration issue with respect to the 2012 BTEX MACT standards for small glycol dehydration units as they apply to units with very low BTEX emissions. The EPA is also soliciting comment and information related to this issue. The Agency also requests any additional relevant information for sources covered by the NESHAP.

Section III of this action discusses in more detail the information identified above. The EPA is providing a 60-day period for the public to submit the requested information.

III. Solicitation of Data and Comments

The following presents the issues on which we are particularly interested in receiving feedback, data, and information.

A. Storage Vessels Without Potential Flash Emissions

We request available data on storage vessels without PFE. Crude oil, condensate, and produced water are typically stored in fixed-roof storage vessels. Some vessels used for storing produced water may be open-top tanks. These fixed-roof vessels, which are operated at or near atmospheric pressure conditions, are typically located in tank batteries at well sites and at centralized gathering facilities. A tank battery refers to the collection of process components used to separate, treat, and store crude oil, condensate, intermediate hydrocarbon liquids, and produced water. The extracted products from production wells enter the tank battery through the production header, which may collect product from many wells.

Emissions from storage vessels are a result of working, breathing, and flash losses. Working losses occur due to the emptying and filling of storage vessels. Breathing losses are the release of gas associated with daily temperature fluctuations and other equilibrium effects. Flash losses occur when a liquid with entrained gases is transferred from a vessel with higher pressure to a vessel with lower pressure, and thus, allowing entrained gases or a portion of the liquid to vaporize or flash. In the oil and natural gas production segment, flashing losses occur when crude oil or condensate flows into a storage vessel from a processing vessel operated at a higher pressure. Typically, the larger the pressure drop, the more flash emissions will occur in the storage vessel. Temperature of the liquid may also influence the amount of flash emissions.

In 1999, the EPA promulgated the NESHAP for the Oil and Natural Gas Production Facilities major source category (40 CFR part 63, subpart HH). The 1999 NESHAP included the MACT standards for storage vessels with PFE, which are defined in subpart HH, 40 CFR 63.761.

The 1999 NESHAP left unregulated storage vessels without PFE (i.e., storage vessels that do not meet the above definition). In the 2011 proposal to revise the Oil and Natural Gas NESHAP, the EPA proposed MACT standards for storage vessels without PFE pursuant to CAA section 112(d)(2) and (3), but did not take final action on that proposal. As explained in the preamble to the 2012 NESHAP revisions, “we need (and intend to gather) additional data on these sources in order to analyze and establish MACT emission standards for this subcategory of storage vessels under section 112(d)(2) and (3) of the CAA.” 77 FR 49503.

We request available data regarding storage vessels without PFE. In particular, we are interested in data and other relevant information characterizing emissions and emission rates of storage vessels in the oil and natural gas production segment that do not have PFE, but that nonetheless emit HAP. We also request information on technologies and/or practices for reducing emissions from storage vessels without PFE.

B. Studies of HAP Emissions From Small Glycol Dehydrators

The EPA is specifically interested in receiving data for units with low inlet concentration of BTEX and the amount of these HAP emissions from small glycol dehydration units. In 2012, pursuant to CAA section 112(d)(2) and (3), the EPA revised 40 CFR part 63, subparts HH and HHH to include MACT standards for “small glycol dehydration units.” See 40 CFR 63.761 and 63.1271. The standards for both existing and new sources of small glycol dehydration units are in the form of a unit-specific BTEX emission limit determined by the equations provided in that subpart.

The EPA recently learned of a potential compliance demonstration issue for certain small glycol dehydration units with very low BTEX emissions. Specifically, we were informed that for certain small glycol dehydrators that operate with low BTEX inlet concentrations, the equations may result in emission standards that are below the detection limit for the reference method used for compliance purposes. If there are units that fit this criterion, it is theoretically possible that neither the source nor the EPA could verify compliance using the methods specified in the rule. To enable us to fully evaluate this issue, we are requesting source data that demonstrates whether compliance with the standard can be verified at small glycol dehydration units for which this is a potential issue. We request that commenters submit estimates on the number of units where this is a potential problem and the data showing the HAP inlet concentrations for these units.

We are also requesting information on emissions of HAP other than BTEX from small glycol dehydrators. As explained above, in the 2012 NESHAP revisions, the EPA established MACT standards for BTEX emitted from small glycol dehydration units. While our data indicate that there is potential for other HAP to be emitted from small glycol dehydration units, we do not have sufficient information to establish MACT standards for other HAP emitted from these units. We are, therefore, requesting data that show the types and quantities of HAP emissions other than BTEX from small glycol dehydration units. In addition to non-BTEX HAP emissions data, we are requesting information on methods employed to control these non-BTEX HAP, including whether BTEX control measures are an effective method for other non-BTEX HAP emitted by the units.