Tailoring Rule Guidance, November 2010

GHG PSD and Title V Guidance

Regarding biogenic emissions sources, EPA indicates that it's still unsure of how to account for them and plans to issue further guidance next year. It's interesting how they think May of 2011 is "well before the start of the second phase of PSD implementation pursuant to the Tailoring Rule"; heck, that could give someone one or two whole months to respond! Here's a relevant section from the document:

“…numerous stakeholders requested that EPA exclude, either partially or wholly, emissions of GHG from bioenergy and other biogenic sources for the purposes of the BACT analysis and the PSD program based on the view that the biomass used to produce bioenergy feedstocks can also be a carbon sink and therefore management of that biomass can play a role in reducing GHGs. EPA plans to provide further guidance on the [sic] how to consider the unique GHG attributes of biomass as fuel.

“Even before EPA takes further action, however, permitting authorities may consider, when carrying out their BACT analyses for GHG, the environmental, energy and economic benefits that may accrue from the use of certain types of biomass and other biogenic sources (e.g., biogas from landfills) for energy generation, consistent with existing air quality standards. In particular, a variety of federal and state policies have recognized that some types of biomass can be part of a national strategy to reduce dependence on fossil fuels and to reduce emissions of GHGs. Federal and state policies, along with a number of state and regional efforts, are currently under way to foster the expansion of renewable resources and promote biomass as a way of addressing climate change and enhancing forest-management. EPA believes that it is appropriate for permitting authorities to account for both existing federal and state policies and their underlying objectives in evaluating the environmental, energy and economic benefits of biomass fuel. Based on these considerations, permitting authorities might determine that, with respect to the biomass component of a facility’s fuel stream, certain types of biomass by themselves are BACT for GHGs. To assist permitting authorities further in considering these factors, as well as to provide a measure of national consistency and certainty, EPA intends to issue guidance in January 2011 that will provide a suggested framework for undertaking an analysis of the environmental, energy and economic benefits of biomass in Step 4 of the top-down BACT process, that, as a result, may enable permitting authorities to simplify and streamline BACT determinations with respect to certain types of biomass.

“… Finally, EPA also plans to determine by May 2011, well before the start of the second phase of PSD implementation pursuant to the Tailoring Rule, whether the issuance of a supplemental rule is appropriate to address whether the Clean Air Act would allow the Agency and permitting authorities or permitted sources, when determining the applicability of PSD permitting requirements to sources of biogenic emissions, to quantify carbon emissions from bioenergy or biogenic sources by applying separate accounting rules for different types of feedstocks that reflect the net impact of their carbon emissions.” pages 9 & 10

Regarding BACT:
Refers to technical “white papers” that provide industry-sector-specific GHG BACT guidance, but it doesn’t say where to find these documents. (page 21)

The guidance explicitly requires consideration of alternate processes that may have better energy efficiency. They offer an example of comparing a supercritical and subcritical coal fired boiler (page 22). The guidance presents a detailed analysis of this issue starting on page 27.
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