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Pennsylvania Updates Air Permitting Exemption Document

Posted: September 15th, 2021

Authors: All4 Staff 

On June 26, 2021, the Pennsylvania Department of Environmental Protection (PADEP) published a notice in the Pennsylvania Bulletin, finalizing amendments to the Air Quality Permit Exemptions document (guidance or exemption document), PADEP ID: 275-2101-003, which was last updated in 2018.  This exemption document is commonly used to evaluate whether a permit or other authorization under 25 Pa. Code Chapter 127 (Construction, Modification, Reactivation, and Operation of Sources) is required for new projects or for changes at an existing facility.  PADEP published draft revisions to the exemption list on July 11, 2020, opened a public comment period through August 24, 2020, and on July 1, 2021, published the revised exemption document as well as a Comment and Response Document pertaining to the comments received.  These documents can be found on PADEP’s eLibrary under the Technical Guidance Final Documents folder.

PADEP states that the revised guidance document is applicable to sources that are constructed or modified after July 1, 2021. As with previous updates, it is not retroactively applicable.  In other words, if a historically applicable exemption was removed, an affected source is not retroactively required to obtain a permit.  Conversely, a source that previously did not qualify for an exemption cannot now qualify for a new exemption unless the source is modified.

In addition to updating, removing, and adding specific exemptions, the changes to the exemption document can be summarized in a few categories:

  • Baghouse exemptions:
    • All original language that stated “Appropriately designed” has been updated to “Designed using good engineering practices”
    • Emissions must not exceed 0.01 gr/dscf of particulate matter (PM), 1,000 lb/yr of a single hazardous air pollutant (HAP) and 1 tpy of total HAP
  • Turbine/engine clarification:
    • Exemption does not apply to newly installed sources of a model year that is not within 5 years of installation date unless they meet New Source Performance Standards (NSPS) for the new sources.
  • HAP emissions cannot include Polychlorinated Biphenyls (PCBs), Chromium (Cr), Mercury (Hg), Lead (Pb), Polycyclic Organic Matter (POM), Dioxins or Furans.
  • A new section was added to specify certain exemptions that will now require a Request for Determination (RFD) of Changes of Minor Significance.

The rest of this blog highlights a few of the more notable updates to specific exemptions from the 2018 Air Quality Permit Exemptions document. Where noted, the regulatory references are within 25 Pa. Code.

The following exemptions were removed:

  • 14(a)(8) Item 1: Incinerators < 75 lb/hr
  • Trivial Activities Item 19: Portable electrical generators
  • Trivial Activities Item 31: Natural gas pressure regulator vents
  • Trivial Activities Item 39: Certain bench-scale laboratory equipment

The following exemptions were added:

  • 14(a)(8) Item 49: Certain bulk material storage bins (requires RFD)
  • 14(a)(9) Item 16: Turbine core replacements with certain conditions

The following exemptions were moved and updated to now require an RFD:

  • 14(a)(8) Item 25 and new Item 45:
    • There are two categories for exemptions in Research and Development facilities. Item 25 provides the exemption thresholds for facilities that do not require an RFD, and Item 45 provides higher thresholds which do require an RFD.
  • 127.14(a)(8) Item 37 (new Item 46): Sources exhausting to a filter/baghouse with particulate loading (before control) below limits in Chapter 123 now require an RFD and previously did not.
  • 127.14(a)(8) Item 41 (new Item 47): Powdered metal sintering furnaces used to require an RFD if using organic lubricants and operating outside the specified limitations of the exemption. All powdered metal sintering furnaces now require an RFD.
  • 127.14(a)(8) Item 43 (new Item 48): Remediation of gasoline or fuel oil contaminated soil, groundwater, or surface water by specified equipment used to require an RFD only if emissions were greater than 1 tpy volatile organic compounds (VOC) or HAP. All specified remediation equipment now require an RFD.

The following exemptions were updated (Note that this list is not exhaustive, and items discussed above are not repeated):

  • 14(a)(8) Item 2: This exemption category was revised from only shot blast and sand blast units to all sources which only emit PM. In addition, the concentration of PM emissions may not exceed 0.01 gr/dscf.
  • 14(a)(8) Item 6: The internal combustion engines exemption criteria are based on actual emissions and do not include emissions from sources which are approved by the Department in plan approvals or the general plan approvals/general operating permits at the facility. This category does not apply if an add-on air-cleaning device is installed.
  • 14(a)(8) Item 12: The 150 tons per hour threshold for portable crushers has been removed.
  • 14(a)(8) Item 15: The storage vessels for VOC exemption criteria does not apply if the source is subject to 25 Pa. Code 129.57.
  • 14(a)(8) Item 30: This exemption no longer applies to solvents with less than 5% VOC by weight.
  • 14(a)(8) Item 39: Combustion units with a rated capacity of 10 MMBtu/hr of heat input continue to be exempt through the use of pipeline quality natural gas, and now also include the use of liquified petroleum gas (LPG) and propane.
  • 14(a)(9) Item 12: Owners and operators installing an air-cleaning device when there is no obligation to install an air-cleaning device must provide a 30-day prior written notification to PADEP.
  • Trivial Activities Item 33: PM was added to VOC and HAP as pollutants that cannot be emitted for equipment used for surface coating, painting, dipping, or spraying operations.

The changes to the exemption list encompass a wide variety of industries and sources; even if you are very familiar with the exemption list, much has changed, so we encourage you to review the applicable exemptions for possible projects at your facility.  For example, 25 Pa. Code §127.14(a)(8) Item 6 pertaining to the nitrogen oxides (NOx) exemption criteria for internal combustion engines is a commonly used exemption category that has been revised.

On the other hand, two major revisions that were added to the 2018 Air Permitting Exemption Document have not been revised further in the July 2021 update.  These categories are 127.14(a)(8) Item 33 which pertains to compressed natural gas dispensing, and 127.14(a)(8) Item 38 which pertains to oil and gas exploration, development, production facilities, and associated equipment.

ALL4 will continue to track updates to this exemption document and provide updates to help you prepare and strategize for your next project.  If you have questions about how this change may affect you, please contact your ALL4 Managing Consultant at info@all4inc.com.


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