UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

REGION IX 

75 Hawthorne Street 

San Francisco, CA 94105·3901 

March 19 7 2010 

In Reply 

Refer To: 

AIR-3 

SAC 06-01 

Jon Maring 

Pacific Gas and Electric Company 

915 Highland Point Drive, Suite 130 

Roseville, CA 95678 

RE: Final Amended PSD Permit for the Colusa Generating Station 

Dear Mr. Maring: 

Enclosed is an Amended PSD Permit issued in accordance with the Prevention of 

Significant Deterioration (PSD) requirements of the Clean Air Act, as amended (42 

U.S.C. § 7401 et seq.), for the construction and operation of the Colusa Generating 

Station (CGS) in Colusa County, California. This Amended PSD Permit revises the PSD 

permit that the U.S. Environmental Protection Agency Region 9 (EPA) issued for the 

CGS on September 29,2008, based on information provided in the application dated 

November 18, 2008. 

EPA requested public comments on a draft permit addressing these revisions 

(Draft Amended Permit) through a public notice published on September 9, 2009 in the 

Colusa Sun-Herald, Willows Journal, and Orland Press Register. On October 21 , 2009, 

EPA granted a request to extend the public comment period by announcing, through a 

public notice published in the same three newspapers, the extension of the comment 

period on the Draft Amended Permit to November 23,2009. We mailed these public 

notices to the necessary parties according to 40 CFR Part 124 and made the 

administrative record for the Draft Amended Permit available at our Region 9 office . .. 

Additionally, we made the Draft Amended Permit, the Ambient Air Quality Impact 

Report (AAQIR), and other supporting documents available on the EPA Region 9 

website. 

EPA received comments from one member of the public. We have enclosed a 

copy of our responses to these comments with the final Amended PSD Permit. These 

documents, along with other documents relevant to the final Amended PSD Permit and 

the index for the entire administrative record, are available online at 

http://www .epa. gov lregion09/air/permitlr9-penni ts-issued.htmL The Amended PSD 

Permit will take effect thirty (30) days after the date of issuance, unless a petition for 

review is timely filed. 

Printed on Recycled Papa 
EPA's Procedures for Decisionmaking at 40 CFR Part 124 require that we notify 

the permit applicant and each person who submitted written comments or requested 

notice of the final permit decision and advise them of the process for petitioning the 

Environmental Appeals Board (EAB) to review any condition of the permit decision. 

Any petition must include a statement of the reasons supporting review, including a 

demonstration that any issues raised in the petition were raised during the public 

comment period to the extent required by the regulations and, when appropriate, a 

showing that the permit condition in question is based on: 

(1) A finding of fact or conclusion oflaw which is clearly erroneous; or 

(2) An exercise of discretion or an important policy consideration which the EAB 

should, in its discretion, review. 

A petition to the EAB for review of the permit decision must be filed not later 

than thirty (30) days after EPA has issued the final permit decision. 

If you have any questions regarding this matter, please contact Shaheerah Kelly of 

the Permits Office at (415) 947-4156. 

Sincerely, 

D~f1W Director, Air Division 

Enclosures: (1) Final Amended PSD Permit 

(2) Response to Comments 

cc: Steve Royal, Pacific Gas & Electric (via email) 

Charles Price, Pacific Gas & Electric (via email) 

Harry Krug, Colusa County Air Pollution Control District 

T. 1. Gomez, Colusa County Air Pollution Control District 

Robert Fletcher, California Air Resources Board 

Dale Rundquist, California Energy Commission 

Chris Davis, California Energy Commission 

Jerry Salamy, CH2M Hill