Public Comments and Responses 

Letter dated January 11, 2011 from Gary Rubenstein, Sierra Research 

Comment #1: The commenter supports Staff’s proposed exclusion of sections (m) and (k) of 40 

CFR 52.21 as they pertain to GHG, noting that this part of the proposal is 

consistent with EPA’s Tailoring Rule and EPA’s “PSD and Title V and Permitting 

Guidance for Greenhouse Gases” (November 2010). 

Response: Thank you for support. Section (k) clearly does not apply to GHG because there 

is no NAAQS for GHG Section (m) clearly does not apply to GHG because, as 

noted in the Guidance Document, it is excluded by section (i)(5)(iii) because it is 

not listed as one of the pollutants in (i)(5)(i). Discussions with staff at EPA 

Region IX indicated that the exclusion of sections (m) and (k) for GHG is 

acceptable. 

Comment #2: Section (n)(2) should also be excluded as it pertains to GHG. This section 

requires the submittal, if requested by the Administrator, of information on air 

quality impacts of the source and of commercial, residential, industrial and other 

growth that has occurred in the area since August 7, 1977. Air quality impacts 

can only be determined by ambient air quality modeling or monitoring, and EPA’s 

Guidance Document does not recommend that PSD applicants be required to 

model or conduct ambient monitoring for CO2 or GHG. 

Response: While sections (k) and (m) are clearly not applicable to GHG (see response to 

comment #1), section (n)(2) is a different matter. The application of this 

requirement is at the discretion of the Air Pollution Control Officer. Although the 

current guidance document does not recommend requiring this modeling and 

monitoring, circumstances could change in the future that would make the 

application of modeling and monitoring of GHG relevant, at which time the 

Administrator would have the option to require it. In discussions with staff of EPA 

Region IX, they indicated that exclusion of section (n)(2) is not acceptable and 

could result in disapproval of the rule. Staff will continue to propose Rule 203 

without an exclusion for section (n)(2). 

Comment #3: Sections (o) and (p) should be excluded as they pertain to GHG. Section (o), 

Additional Impacts Analysis, requires an assessment of the impairment to 

visibility, soils, vegetation, and air quality that would occur as a result of the 

growth associated with the proposed project. Section (p) requires an 

assessment of the impact of the proposed source on Class I areas. EPA’s 

Guidance Document states that it is not necessary for applicants or permitting 

authorities to assess impacts from GHG in the context of additional impacts 

analysis or Class I area provisions. 

Response: As noted in the comment, the current Guidance Document does not recommend 

these additional analyses and assessments for GHG. It is expected that 

permitting authorities will follow the guidance and not require them at this time. 

However, circumstances could change in the future that would make these 

requirements relevant to GHG, at which time new guidance could be issued. If 

the District excluded sections (o) and (p) in the proposed amendments, it could 
result in a requirement to amend Rule 203 in the future to incorporate these 

sections as they pertain to GHG. In discussions with staff of EPA Region IX, 

they indicated that exclusion of sections (o) and (p) is not acceptable and could 

result in disapproval of the rule. Staff will continue to propose Rule 203 without 

exclusions for sections (o) and (p). 

The comment letter begins on the following page.