4 The record articles

Revised GP-5 Is Final, So Now What?

Posted: March 29th, 2013

Author: All4 Staff 

The Pennsylvania Department of Environmental Protection (PADEP) published the final General Plan Approval and/or General Operating Permit for Natural Gas Compression and/or Processing Facilities (GP-5) on February 2, 2013.  The final GP-5 and an associated fact sheet are available on PADEP’s website.  For those familiar with the previous versions of GP-5 (i.e., General Permit for Natural Gas, Coal Bed Methane or Gob Gas Production or Recovery Facilities) dating back to 1997, the “new” GP-5 represents a significant change in applicability, scope, and requirements.  In essence, GP-5 has been overhauled as summarized below.

GP-5 Applicability and Scope

The applicability of GP-5 has changed dramatically with its revision, in that natural gas “production” is no longer covered under GP-5.  Major sources are also prohibited from using GP-5, and records of actual emissions from GP-5 facilities must be maintained on a rolling 12-month basis to demonstrate that the facility is not a major source. Concurrent with the finalization of GP-5, PADEP proposed a “conditional” exemption for “Category No. 38” pertaining to oil and gas exploration, development, and production facilities.  This conditional exemption is anticipated to be finalized in the next few months.  GP-5 now applies to a very broad list of sources and is organized into the following 10 sections, each pertaining to specific operations under the broad natural gas compression and/or processing facility umbrella:

  • Section A – General Conditions identifies the regulatory basis/authorization of GP-5, specifies general requirements such as definitions, applicability, scope, testing, prohibitions, fees, recordkeeping, notification, and identification of potentially applicable federal standards (e.g., NSPS and NESHAP).
  • Section B – Natural Gas Fired Spark Ignition Engines identifies emission standards for existing and new engines, including best available technology (BAT) based standards for new engines that are, in most cases, more stringent than potentially applicable NSPS and/or NESHAP standards, and specifies the obligation to comply with 40 CFR Part 60, Subpart JJJJ, and 40 CFR Part 63, Subpart ZZZZ.  Section B also specifies requirements associated with engine startup and shutdown, performance testing, work practice standards, and monitoring, recordkeeping, and reporting requirements.
  • Section C – Natural Gas Fired Simple Cycle Combustion Turbines identifies emissions standards for new turbines, including BAT based standards for pollutants not regulated under potentially applicable NSPS.  Section C also specifies requirements associated with turbine startup and shutdown, performance testing, work practice standards, and monitoring, recordkeeping, and reporting requirements.
  • Section D – Centrifugal Compressors specifies the obligation to comply with applicable requirements specified in 40 CFR Part 60, Subpart OOOO for centrifugal compressors.
  • Section E – Storage Vessels/Tanks specifies the obligation to comply with applicable requirements specified in 40 CFR Part 60, Subparts Kb and OOOO, 40 CFR Part 63, Subpart HH, 25 Pa. Code §§ 127.1 and 127.12(a)(5), 25 Pa. Code § 129.56, and 25 Pa. Code § 129.57.
  • Section F – Glycol Dehydrators specifies the obligation to comply with 40 CFR Part 63, Subpart HH, as applicable, as well as requirements for existing glycol dehydrators and for new glycol dehydrators that are not subject to 40 CFR Part 63, Subpart HH.
  • Section G – Onshore Natural Gas Processing Plants specifies the obligation for fractionation units to comply with applicable requirements of 40 CFR Part 60, Subpart KKK
  • Section H – Equipment Leaks requires that natural gas compression and/or processing facilities conduct leak detection and repair (LDAR) activities including monthly audible, visual, and olfactory (AFO) inspections, as well as quarterly leak detection surveys using forward looking infrared (FLIR) cameras or other devices as approved by PADEP.
  • Section I – Pneumatic Controllers specifies the requirement to comply with applicable requirements in 40 CFR Part 60, Subpart OOOO.
  • Section J – Sweetening Units specifies the obligation to comply with applicable requirements in 40 CFR Part 60, Subparts KKK and OOOO.

Other GP-5 Requirements

As mentioned above, major sources are prohibited from using GP-5, so major facilities that elect to use GP-5 will become synthetic minor sources by default.  A facility is a major source in most of Pennsylvania for Title V permitting purposes if its potential to emit (PTE) exceeds any of the following thresholds in units of tons per year (tpy):

  • Nitrogen oxides (NOX), carbon monoxide (CO), sulfur oxides (SOX), particulate matter with an aerodynamic diameter less than 10 microns (PM10) and 2.5 microns (PM2.5) – 100 tpy
  • Volatile organic compounds (VOC) – 50 tpy
  • Any individual hazardous air pollutant (HAP) – 10 tpy
  • Total HAPs – 25 tpy
  • Greenhouse gases (GHG), expressed as carbon dioxide equivalent (CO2e) – 100,000 tpy

As a synthetic minor source, a system to calculate emissions from each operation at the facility and to tabulate emissions of each pollutant on both a monthly and on a rolling 12-month basis will need to be established.  The requirement to calculate and tabulate emissions to demonstrate the synthetic minor status of the facility on an on-going basis is specified in Section A of GP-5.

While the need to calculate and tabulate emissions from individual operations under GP-5 may not seem burdensome, it should be noted that applicants using GP-5 must also include a completed Attachment A – Questionnaire and Checklist for Single Source Determination accompanied by a map/layout of adjacent facilities (e.g., well(s), compressor stations, processing plants, etc.) which are under common control.  Such a determination could quickly and unexpectedly increase the size of a facility via the dreaded practice of “source aggregation.”

Finally, it should be noted that the use of the new GP-5 for a modification at an existing natural gas compression and/or processing facility could subject other “non-modified” emissions units at the facility to GP-5 requirements that are specified for such emissions units, including the Section H LDAR requirements. This interpretation at least in part explains PADEP’s inclusion of requirements for “existing” reciprocating internal combustion engines and glycol dehydrators in the final GP-5

Other Permitting Options

In Pennsylvania (and in most states), limited air permitting options are available for new and modified sources and include the use of permitting exemptions (as applicable), general permits, or construction permit applications (i.e., Plan Approval Applications).  If a source is not explicitly exempt from the requirement to obtain a Plan Approval, an applicant can request that PADEP evaluate whether a new source or modification is exempt from permitting requirements via the Request for Determination of Changes of Minor Significance and Exemption from Plan Approval/Operating Permit Under Pa Code § 127.14 or § 127.449 process (a.k.a. the RFD process).  If a new source or modification is not exempt from permitting, the permitting options default to a general permit (if applicable) or to a construction permit application (i.e., Plan Approval Application).

The advantages of a general permit include timing (i.e., 30 day turn around) and no public comment period.  The disadvantages include permit conditions that are “set” with no ability to customize the permit based on site and/or equipment specific conditions.  The advantages and disadvantages of a Plan Approval Application path are directly opposite from a general permit. The advantage is the ability to craft a permit application that reflects the nuances of site and/or equipment conditions that more closely reflect the variability of actual operations.  The disadvantage is that the preparation, technical review, and public review process for the construction permitting takes additional time and can easily exceed six months.

So Now What?

In many cases for the oil and gas industry, the timing and certainty advantages associated with the use of a general permit (including GP-5) will at first glance seem to far outweigh the time penalty that is typically associated with preparing and submitting a Plan Approval Application.  Our advice to facilities that are facing decisions regarding air permitting options would be to proceed with caution.  Make sure that the compliance obligations (e.g., notification, air pollution control, testing, monitoring, recordkeeping, and reporting) associated with any underlying applicable requirement (e.g., NSPS and NESHAP) are fully understood and are considered during the design phase of the new source or modification.  Such requirements are incorporated by reference and a GP-5 permit will not specifically identify the individual NSPS and NESHAP compliance obligations that may be applicable to a facility.  It is also important to understand how existing, un-modified emissions units may be impacted by the requirements specified for such units in GP-5 before a decision is made regarding the use of GP-5.  Finally, the possible future expansion of a site may make the Plan Approval process a much more flexible permitting option than a general permit.

ALL4 can help you determine the most optimal permitting strategy for your project.  Please contact John Slade (610.933.5246 x136; jslade@all4inc.com) or Roy Rakiewicz (610.933.5246 x127; rrakiewicz@all4inc.com) to discuss your air permitting needs.


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