4 The record articles

Boiler MACT Reconsideration Comments Not Without A Few Clever Responses

Posted: March 20th, 2015

Author: All4 Staff 

There are already too many regulations. This is not necessary.

– Anonymous

This comment, two (2) simple sentences that were submitted during the public comment period for the proposed reconsiderations to the Area Source Boiler MACT rule, may have taken the words right out of the mouth of our blog readers. Boiler MACT (i.e., Maximum Achievable Control Technology standards for both Major Source and Area Source versions of the rule) has been a large part of ALL4’s project work and strategic planning for what seems like forever. As we continue to deal with an ever-evolving rule, it feels like there may never be an end to this journey. But we’re getting closer – the latest step in the journey began late last year, as we discussed in a December 3, 2014 blog post. This blog post provided a sneak preview of the proposed Boiler MACT reconsiderations that eventually were published on January 21, 2015. The public comment period for the proposed reconsiderations ended on March 9, 2015, and ALL4’s 4 Rules Initiative Team has been reviewing the comments posted in the dockets for both Major Source and Area Source Boiler MACT. Through this review, we have gained a sense of which portions of the proposed reconsiderations have generated the most buzz. In no particular order, the following list provides a sampling of the more common comments submitted by industry, regulatory agencies, trade groups, and the public; in other words, what people are talking about. 

  • The applicability of Boiler MACT to natural gas electric utility steam generating units (EGUs) was a hot topic, specifically as it relates to the amount of backup fuel oil that such a unit may fire during the course of a year. Commenters noted an inconsistency between the definitions in Boiler MACT and 40 CFR Part 63, Subpart UUUUU (Utility MATS Rule) that causes confusion with which rule applies.
  • The definitions of startup and shutdown generated comments in favor of, in opposition to, and in favor of but with additional recommendations to the proposed revisions. Those opposed to the revisions continue to push for emission limits to apply during these periods, or elimination of the “startup plus 4 hours” allowance.  These commenters claim previous legal precedents and related legal decisions as the basis for their position. Proponents of the proposed revisions appreciate the consideration of the operational challenges during these periods and believe the rule is largely headed in the right direction with these changes. However, a subset of the proponents recommended additional clean fuel (e.g., dry biomass) and a longer “plus hours” time to accommodate startup and shutdown for certain boiler types.
  • Not surprisingly, the comments regarding the increase of the minimum CO emission standard to 130 parts per million by volume dry basis (ppmvd) corrected to 3% oxygen were aligned with industry (in support of the proposed revision) versus the environmental organizations (against the proposed revision).
  • Affirmative defense, a topic that has been an ALL4 blog staple, generated comments along the lines of the proposed revisions to the CO emission standard. Many industry and trade group commenters are adamant that affirmative defense needs to stay in the rule, while the non-industry environmental commenters continue to show their support of its proposed withdrawal from the rule. Based on everything that is going on with affirmative defense in other MACT standards and with the looming state SIP call action, I believe that affirmative defense will not remain in Boiler MACT.
  • Widespread industry support of the proposed alternative particular matter (PM) standard for new area source oil-fired boilers that combust low sulfur oil was evident in the docket comments.
  • Conversly, industry was strongly opposed to the proposed provisions that specify what constitutes an emissions violation for boilers using PM continuous parametric monitoring systems (CPMS). The focus was on the following proposed provision:
    • For any exceedance of the 30-boiler-operating-day PM CPMS value, the owner or operator must (1) inspect the control device within 48 hours and, if a cause is identified, take corrective action as soon as possible, and (2) conduct a new performance test to verify or reestablish the operating limit within 30 calendar days. Additional exceedances that occur between the original exceedance and the performance test do not trigger another test. Up to four performance tests may be triggered in a 12-month rolling period without additional consequences. However, each additional performance test that is triggered would constitute a separate presumptive violation.

Industry is pushing back that exceedances should not be presumed to be emission violations and the response times should be extended. Industry supports the proposed revision to remove the requirement to certify PM CPMS. 

The next big questions are what does U.S. EPA do with these comments, when will changes to the rule occur, and will the changes result in a new compliance date? Right now we are not finding many answers to these questions but will continue to search. To our readers, we ask that you share information (we even have a comment submittal process of our own at the bottom of this blog post!) on upcoming milestones and other topics of interest that resulted from the comment period. The more we all know, the better we will all be able to deal with the challenges of these rules. 


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