The Virginia Department of Environmental Quality (DEQ) recently proposed a guidance document to revise the definition of “sudden and reasonably unforeseeable events” under 9VAC5-80-1110 and 9VAC5-540-20 to allow the use of emergency generators for a planned outage if the source meets the proposed criteria in the guidance document. Historically, Virginia DEQ has excluded planned or scheduled power outages from the definition of an “emergency.” However, this proposed guidance recognizes that certain planned outages, when beyond a facility’s control and with limited notice, may qualify as emergencies requiring emergency generator operation.

Under this framework, a planned outage may be considered a “sudden and reasonably unforeseeable” event if the operator receives notice from the electricity service provider fourteen (14) calendar days or less in advance. The permittee must complete the following in response to this notification from the electricity service provider:

• Within 24 hours of receiving outage notice, the permittee must notify Virginia DEQ and submit the written notice from the utility informing the permittee of the time, place, expected duration, and manner of the scheduled outage. This must be accompanied by a written explanation and supporting documentation justifying generator use, as well as a plan of action specifying the expected duration of operation, generator identification, and rated capacities.
• If the outage extends beyond a single day, the permittee must provide daily reports detailing generator operating hours and fuel consumption.
• Within five (5) business days following power restoration, a final report must be submitted to Virginia DEQ documenting the total operating hours and fuel use for each generator utilized.

Virginia DEQ emphasizes that all operations must remain in full compliance with existing air permit conditions. Virginia DEQ also clarifies that operators claiming extenuating circumstances, such as regional shortages of portable generators due to widespread outages or natural disasters, must document these conditions in writing, and Virginia DEQ may consider them as part of determining whether the situation qualifies as an emergency.

The proposed APG-578 Sudden and Reasonably Unforeseeable Events in the Context of Planned Electric Outages guidance was published in the Virginia Register on November 3, 2025 and can be found here. The public comment period will be open through December 3, 2025 and comments can be posted on this website. Please contact Susan Barnes at Trinity’s Washington, D.C. office (240.379.7490) or Farshid Kiani at Trinity’s Virginia office (540.400.8041) if you would like to understand the impact of this rule on your operations or would like assistance with submitting any comments on the proposed guidance document.