Re: Opposition to Guidance Memo APG-578 – Planned Outages Should Not Qualify as “Sudden and Reasonably Unforeseeable Events”
I oppose the adoption of Guidance Memo APG-578, which would allow planned electric outages with up to fourteen days’ notice to qualify as “sudden and reasonably unforeseeable events,” thus permitting the operation of Tier-2 emergency generators during non-emergency conditions. This change weakens long-standing environmental protection standards and undermines the regulatory purpose of emergency-only generator classification.
1. Planned outages are not legally consistent with the definition of “sudden” or “unforeseeable.”
Because a planned outage with notice is not sudden, nor reasonably unforeseeable under 9VAC 5-80 and 9VAC 5-540-20 definitions of emergency, APG-578 weakens regulatory integrity and reverses prior DEQ interpretation that scheduled outages do not qualify as emergency conditions (guidance summary, p.1). APG-578 would extend emergency status to events with nearly two weeks’ advance notification. Receiving notice and not being prepared is an operational planning issue—not an unforeseen event. Past DEQ interpretation correctly held that scheduled or planned outages did not meet emergency criteria.
2. The amendment increases use of Tier-2 generators and therefore emissions.
The memo acknowledges that Tier-2 engines lack advanced air-pollution controls, while Tier-4 units represent a substantially cleaner alternative. Allowing Tier-2 operation during planned outages creates avoidable increases in particulate matter and NOx emissions that are otherwise prohibited in non-emergency conditions. In regions with dense infrastructure, particularly data-center corridors, simultaneous Tier-2 operation during routine grid maintenance could result in short-term but significant air-quality deterioration.
3. APG-578 undermines DEQ’s stated intent to incentivize cleaner technology adoption.
The guidance expresses a desire to transition operators toward Tier-4 or equivalent systems, yet it provides a compliance pathway that legitimizes reliance on depreciated Tier-2 fleets and removes pressure to upgrade. When a facility can legally operate legacy engines during known outages, the most cost-efficient choice becomes continued dependence on higher-emitting equipment. Incentives do not function when non-compliant alternatives are made easier, cheaper, and permitted.
4. Prolonged operation risk amplifies community exposure.
Unlike true emergency events—which are typically unplanned and time-limited—scheduled outages can last days. APG-578 allows continuous Tier-2 operation during this period with only daily fuel-use reporting. Residents would bear extended pollution exposure despite viable mitigation alternatives such as portable Tier-4 rental units, shared-reserve generation, or natural-gas backup systems.
Recommendation
For the reasons above, I request that DEQ rescind APG-578 and retain the established interpretation that planned or scheduled grid outages do not constitute “sudden and reasonably unforeseeable events.” If the Department wishes to support reliability during short-notice outages, a more protective approach would be to allow temporary generator authorization only where Tier-4 or cleaner technology is demonstrably unavailable - requiring affirmative proof rather than default permission.
In protecting Virginia’s air and public health, the standard should remain clear: planned outages may require preparation, but preparation should not come at the expense of environmental safeguards.