# Re: White Papers on Methane and Volatile Organic Co mpound (VOC) Emissions in the Oil and Natural Gas Sector

Dear Sir or Madam:

On April 15, 2014, the U.S. Environmental Protectio n Agency (EPA) Office of Air Quality Planning and S tandards released for external peer review five technical wh ite papers on potentially significant sources of em issions in the oil and gas industry sector. These white papers focus on technical issues covering emissions and m itigation techniques that target methane and VOC emissions fr om compressors, well completions and ongoing production of hydraulically fractured oil wells, eq uipment leaks, liquids unloading, and pneumatic d evices. The Texas Commission on Environmental Quality (TCEQ) ap preciates the opportunity to comment on these white papers. TCEQ’s comments are provided below.

In general, more data is needed to substantiate and confirm the emission estimates presented in the EP A’s white papers. While it is not unusual to establish control requirements based on expected emissions f rom a facility or single source, the studies and emission estimates used in the white papers rely on the EPA’s definition of “facility” as established for the EPA’s Greenhou se Gas Reporting Program (GHGRP). In general, a “facility” for purposes of the GHGRP means all co­located emission sources that are comm only owned or operated. However, the GHGRP has developed a specialized facility definition for onshore produ ction. For onshore production, the “facility” includes all emissions associated with wells owned or operated by a single company in a specific hydrocarbon producing basin. [1] (1 Oil and Natural Gas Sector Hydraulically Fractur ed Oil Well Completions and Associated Gas during O ngoing Production, page 21, footnote 9; Oil and Natural Ga s Sector Liquids Unloading Processes page 5, footno te 2; Oil and Natural Gas Sector Pneumatic Devices, page 20, footnote 11.) The use of this definition makes determining emissi ons from each unit or piece of equipment difficult, if not impossible to verify. Since control is usually requ ired for each individual piece of equipment, the la ck of this information makes evaluating the cost effectiveness of any potential controls or mitigation techniques similarly impossible. Where the studies referenced in the white papers us ed a more traditional understanding of the term “fa cility”, meaning each individual piece of equipment, compres sor, or controller, the TCEQ has concern about the limited data sets used and would recommend additional studi es to verify the accuracy and representativeness of the numbers and factors derived. The great variation in the composition of oil and gas that exists across different fields can result in vastly different emissions pro files and thus additional research is warranted to verify the accuracy and representativeness of the expected emi ssions. Moreover, if the information in the white p apers or later studies is relied upon to develop required co ntrols or mitigation techniques, the TCEQ recommend s consideration of a range of controls or techniques that would correlate to the differing standards, orfactors based on the particular composition or characterist ics of the material being handled or processed. Thi s approach 

### Hagle <steve.hagle@tceq.texas.gov> Steve

Mon 6/16/2014 6:21 PM

To: OilandGas.Whitepapers <OilandGas.Whitepapers@epa.go v>;

Cc: Mike Wilson <mike.wilson@tceq.texas.gov>; Mike Hoke <mike.hoke@tceq.texas.gov>; Jayme Sadlier <jayme.sadlier@tceq.texas.gov>; Erin Selvera <Erin. Selvera@tceq.texas.gov>; Keith Sheedy <keith.sheedy @tceq.texas.gov>; 

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**- OilandGas.Whitepapers** 

**8/ 27/** **2014 https://pod51045.outlook.com/owa/OilandGas.Whitepapers@epa.gov/** would help to ensure the appropriate level of contr ol for the material and provide the flexibility that a “ one

­ size

fits­all” approach cannot achieve. Additionally, while the TCEQ encourages innovation and development of new processes and controls for a ir emissions in general, when establishing any standar ds or requirements it is crucial to rely on proven control technologies that are commercially available. The f ailure to do so may lead to a new standard or contr ol that is not achievable for all of the affected facilities. For example, in the evaluation of Compressor Emissi ons Mitigation Techniques for Reciprocating Compressor Gas Recovery, EPA refers to a system developed by R EM Technology, Inc. that captures gas that would other wise be vented and routes it back to the compressorengine to be used as fuel. However, no cost data was avail able to properly evaluate the technology as a viabl e, costeffective control or mitigation technique and, alth ough commercially available, it is unknown if this system is available to the scores of facilities that may need to use it if required. The TCEQ encourages the EPAto evaluate only proven control technologies that are commercia lly available in volumes that could support the ind ustry as a basis for establishing any future standards or requ irements. If you have any questions about these comments, ple ase contact Mr. Michael Wilson, P.E., Director, AirPermits Division, Office of Air, at (512) 239­1922, or at m ike.wilson@tceq.texas.gov.

Sincerely,

Steve Hagle, P.E., Deputy Director, Office of Air Texas Commission on Environmental Quality steve.hagle@tceq.texas.gov 512­239­1295 

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**- OilandGas.Whitepapers** 

**8/ 27/** **2014 https://pod51045.outlook.com/owa/OilandGas.Whitepapers@epa.gov/**