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Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

TABLE OF CONTENTS

I. INTRODUCTION................................................................................................................. 1

II. EPA RESPONSES TO PUBLIC COMMENTS ................................................................ 2

A. COMMENTS ON PUBLIC PROCESS ................................................................................... 2

B. COMMENTS ON BEST AVAILABLE CONTROL TECHNOLOGY DETERMINATIONS ........ 6

C. COMMENTS ON ANALYSIS OF SOURCE IMPACTS ON AIR QUALITY ............................ 13

D. COMMENTS ON ENDANGERED SPECIES ACT CONSULTATION PROCESS .................... 15

E. OTHER COMMENTS ...................................................................................................... 17

III. ADMINISTRATIVE CORRECTIONS ............................................................................ 20
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

1

I. Introduction 

On September 9, 2009, the United States Environmental Protection Agency Region 9 (“EPA”) 

proposed to issue an amended Prevention of Significant Deterioration (“PSD”) permit to the 

Pacific Gas & Electric Company (“PG&E” or “applicant”) containing minor revisions to an 

existing PSD permit that authorized the construction and operation of a 660 mega-watt natural 

gas-fueled combined cycle power plant known as the Colusa Generating Station (“CGS”), in 

Colusa County, California. Although the proposed changes to the source do not trigger new PSD 

requirements because they will not result in a “significant emissions increase” as defined in 40 

CFR 52.21(b)(40) (see 40 CFR 52.21(a)(2)(iv)), EPA evaluated the application to determine 

whether the changes would trigger new requirements and whether the requested permit revisions 

would ensure that the PSD requirements (e.g., BACT and protection of ambient air quality 

standards) continue to be met. The public comment period on the proposal (“Draft Amended 

Permit”) began on September 9, 2009, and closed on October 12, 2009. On October 21, 2009, 

EPA granted a request to extend the public comment period by providing an additional 30 days 

for public comment, beginning October 21, 2009 and ending November 23, 2009. The purpose 

of this document is to respond to every significant issue raised in the public comments received 

during the public comment period and to explain the changes that EPA has made in this final 

Amended PSD Permit. 

EPA announced the public comment period through public notices published in the Colusa SunHerald, Willows Journal, and Orland Press Register and posted on our website. EPA mailed the 

public notices to the required entities under 40 CFR part 124. 

The administrative record for the Draft Amended Permit, which includes the Draft Amended 

Permit, all data submitted by the applicant in support of the Draft Amended Permit and 

correspondence between EPA and the applicant, was made available at EPA’s Region 9 office. 

Additionally, the Draft Amended Permit, the Ambient Air Quality Impact Report (“AAQIR”) 

and other supporting documents were made available on the EPA Region 9 website. 

On October 12, 2009, EPA received an e-mail from Rob Simpson (the “commenter”) attaching 

comments on the Draft Amended Permit and requesting that EPA extend the comment period by 

an additional 45 days. As noted above, in response to this request, EPA extended the public 

comment period to November 23, 2009. On November 23, 2009, EPA received a second e-mail 

from Rob Simpson attaching additional comments and repeating many of his October 12, 2009 

comments on the Draft Amended Permit. EPA did not receive any other comments on the Draft 

Amended Permit. 

 

 
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

2

II. EPA Responses to Public Comments 

 

This document summarizes or recites Mr. Simpson’s comments and provides EPA’s responses. 

Comments on a single topic have been grouped together into a single comment summary and are 

addressed by one response from EPA. The full text of all the comments we received is available 

in the administrative record for the permit, which is available for inspection at our regional office 

at 75 Hawthorne Street, San Francisco, CA, 94105. Documents relevant to the permit and the 

index for the entire administrative record are also available online at 

http://www.epa.gov/region09/air/permit/r9-permits-issued.html. 

A. COMMENTS ON PUBLIC PROCESS 

Comment A.1: In the comments submitted on October 12, 2009, the commenter stated that he 

had not received notice of the initial PSD permit or the revised permit EPA was proposing to 

issue (the Draft Amended Permit). The commenter stated that he had repeatedly asked to be 

added to the EPA Region 9 interested parties list but had only recently discovered the proposed 

action and did not have sufficient time to effectively comment on this action. As such, the 

commenter requested that EPA extend the comment period by 45 days so that he could 

participate. 

Response A.1: EPA initially announced a public comment period on the Draft Amended Permit 

through a public notice published on September 9, 2009 in three semi-weekly newspapers of 

general circulation in Colusa and Glenn Counties: the Colusa Sun-Herald, Willows Journal, and

Orland Press Register.

1

 The notice stated that EPA would accept public comments on the Draft 

Amended Permit until October 12, 2009. It appears the commenter received this general public 

notice, as demonstrated by the comments he submitted on October 12, 2009. EPA did not, 

however, provide the commenter with particularized notice of the Draft Amended Permit we 

announced on September 9, 2009.2 See Mailing List, Colusa Generating Station PSD Permit 

Revision, Permit No. SAC 06-01, September 2009. In response to this comment, EPA extended 

the public comment period on the Draft Amended Permit for an additional 30 days, to November 

23, 2009, to provide commenters a reasonable opportunity to comply with the requirements of 40 

CFR § 124.13. EPA’s public notice of the additional 30-day comment period was published on 

October 21, 2009, in the same three newspapers that had published the initial public notice. EPA 

provided particularized notice of the extended public comment period on the Draft Amended 

Permit to the commenter by e-mail (which was the only address he had provided to EPA for 

notification purposes) on October 21, 2009, and to all other parties on EPA’s mail/e-mail 

distribution list for the Draft Amended Permit. See Mailing List, Colusa Generating Station PSD 

 

1

 The Colusa Sun-Herald publishes twice a week on Wednesdays and Saturdays and is the only 

newspaper of general circulation in Colusa County. The Willows Journal and Orland Press 

Register also publish twice a week on Wednesdays and Saturdays and are newspapers of general 

circulation in neighboring Glenn County. 

2

 As the commenter has not specifically argued that he was entitled to receive particularized 

notice of the initial PSD permit, which we issued on September 29, 2008, nor identified any 

deficiency in EPA’s public process for that permit, we are not addressing the commenter’s brief 

reference to the public notice for that prior action. 
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

3

Permit Revision, Permit No. SAC 06-01, October 2009.3 EPA’s extension of the comment 

period to November 23, 2009 effectively provided commenters with an additional 42 days 

beyond the close of the initial comment period to submit comments, thereby addressing the 

commenter’s request. 

Comment A.2: The commenter stated that a “recurring concern [he had] with PSD permits is 

failure to provide for public participation.” Quoting language from In re: Russell City Energy 

Center, PSD Appeal No. 08-01 (EAB Jul. 29, 2008), 14 E.A.D.__, about the public notice and 

participation rights established in the CAA and 40 CFR part 124, the commenter stated that he 

had hoped this decision would provide “guidance that would be followed in permitting 

polluters,” and that he had “found no evidence of a public Notice for this facility that includes 

the information needed for ‘informed public participation’ which is a demonstration of the 

projects effects on air quality in relationship to the National Ambient Air Quality Standards.” 

The commenter stated that the notices he had seen “include no indication of the volume of 

pollutants,” and that “Original Notices for the facility appear to include a gross weight of 

pollutants but no basis in relationship to air quality.” 

Response A.2: EPA provided adequate public notice of the Draft Amended Permit in 

accordance with the requirements of 40 CFR part 124 and disagrees with the commenter. 

Specifically, 40 CFR 124.10(c) requires that EPA provide public notice of a draft PSD permit 

by: (1) mailing a copy of the notice to the individuals and entities listed in section 124.10(c)(1); 

(2) publishing a notice in a daily or weekly newspaper within the area affected by the facility; 

and (3) implementing any other method reasonably calculated to give actual notice of the action 

in question to the persons potentially affected by it. Section 124.10(d) specifies the information 

that all public notices must contain, including information about the permittee and its operations; 

the name, address and telephone number of a person from whom interested persons may obtain 

further information; a brief description of the comment procedures required under part 124; and 

the location and times at which the administrative record will be available for public inspection. 

EPA initially announced a public comment period on the Draft Amended Permit through a public 

notice published on September 9, 2009 in three semi-weekly newspapers of general circulation in 

Colusa and Glenn Counties. See Response A.1 above. This public notice contained the 

information required by 40 CFR 124.10(d), including information about the CGS and its 

operations; EPA’s proposed revisions to the facility’s existing PSD permit; the name, address 

and telephone number of an EPA staff person to whom questions could be directed; and a brief 

description of the comment procedures required under part 124. The notice stated that EPA was 

providing 30 days for comment in accordance with section 124.10(b). The notice also stated that 

the Draft Amended Permit, the AAQIR, and other documents relevant to the Draft Amended 

Permit would be available at the EPA Region 9 Office and on the Region 9 website and provided 

the location and times at which the administrative record would be available for public 

 

3

 The mailing list for the extended public comment period, which began on October 21, 2009, 

included a number of individuals on EPA’s general distribution list for PSD permits, including 

the commenter, who had been inadvertently omitted from the mailing list for the initial public 

comment period. The particularized notice that EPA sent to these individuals of the extended 

comment period corrected this procedural error. 
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

4

inspection. EPA mailed this notice to the applicant, the Colusa County Air Pollution Control 

District (CCAPCD), various other federal, state, county, municipal, and tribal government 

agencies, and to a number of citizens and non-governmental organizations that had requested to 

be on EPA’s mail or e-mail distribution list for PSD permitting actions. See Mailing List, Colusa 

Generating Station PSD Permit Revision, Permit No. SAC 06-01, September 2009. 

Subsequently, in response to the commenter’s request for additional time to comment, EPA 

provided notice that it was extending the comment period for an additional 30 days. See

Response A.1; see also Mailing List, Colusa Generating Station PSD Permit Revision, Permit 

No. SAC 06-01, October 2009. These methods provided the notice called for in 40 CFR 124.10. 

The commenter suggests that EPA’s public notice should have contained information about the 

volume of pollutants at issue and the air quality impacts of the proposed action in relation to the 

National Ambient Air Quality Standards (NAAQS), and that such information is necessary to 

allow for informed public participation. We disagree. Part 124 requires that a public notice of a 

draft PSD permit include information about the location and times at which the administrative 

record will be open for public inspection, and requires that the administrative record include the 

application, the draft permit, the statement of basis or fact sheet containing EPA’s analyses, and 

other supporting documentation that may provide information about the air quality impacts of the 

proposed action. 40 CFR §§ 124.10(d)(1)(vi), 124.7, 124.8, 124.9(b). Part 124 does not, 

however, require that information about the volume of pollutants or air quality impacts be 

included in the public notice itself. 

Comment A.3: The commenter stated that he had “found no evidence that Region 9 

incorporated the interested parties lists from the [California Energy Commission’s] proceeding 

or the Air Districts proceeding,” “no evidence the Notice was provided to the County 

Supervisors or other required government officials,” and “no evidence of outreach or 

development of lists of potentially interested individuals, organizations or agencies.” 

Response A.3: The commenter’s assertions appear to rest on incorrect legal and factual bases. 

First, to the extent the commenter intended to argue that part 124 requires EPA to provide notice 

to all parties included on mailing lists developed by the California Energy Commission (CEC) 

and/or the CCAPCD as part of their respective licensing or permitting processes, this is legally 

incorrect. Part 124 requires that EPA send public notices of draft PSD permits to specific 

federal, state, county, municipal, and tribal government agencies, in addition to persons on a 

mailing list developed by EPA. 40 CFR 124.10(c)(1). It does not require that EPA send public 

notices to entities included on a list developed by another agency.4

 Second, the commenter’s 

assertion that EPA did not provide public notice to county supervisors or other required 

government officials is factually incorrect. See Response A.2 above. Finally, to the extent the 

commenter intended to argue that EPA did not solicit public involvement or develop a list of 

 

4

 We note that for this particular permitting action, EPA did obtain the CEC’s most recent 

mailing list for the CGS licensing action, and we included all persons and entities on the CEC’s 

list in our mailing list for the Draft Amended Permit. See E-mail dated August 26, 2009, from 

Chris Davis (CEC) to Shaheerah Kelly (EPA Region 9), “Re: Mailing list for the Colusa 

Generating Station”; see also Mailing List, Colusa Generating Station PSD Permit Revision, 

Permit No. SAC 06-01, September 2009. 
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

5

interested persons and entities for public notice purposes, this is also factually incorrect. EPA 

solicits public interest in PSD and other permitting actions through the EPA Region 9 website, 

which invites members of the public to join our e-mail distribution lists by entering their contact 

information and identifying the facilities or types of permits about which they would like to 

receive information. See http://www.epa.gov/region09/air/permit/psd-public-guidelines.html. 

As noted above, EPA sent the October 21, 2009 public notice to all persons who had requested to 

be on EPA’s mail or e-mail distribution list for PSD permitting actions, in addition to all other 

required entities under part 124. See Responses A.1 and A.2 above. Therefore, we disagree with 

the commenter’s assertions. 

Moreover, the commenter cannot claim that he was harmed by any alleged deficiency in EPA’s 

public process, given that he received particularized notice of the Draft Amended Permit through 

EPA’s mailing list. See Response A.1. The commenter has no standing to complain about third 

parties not being mailed notice of the Draft Amended Permit. See In re Russell City Energy 

Center, PSD Appeal No. 08-01, slip op. at 32 (EAB, July 29, 2008) (citing J&L Specialty Prods., 

5 E.A.D. at 79 (stating that “absent any alleged harm to [petitioner], we fail to see how 

[petitioner] has standing to complain about someone else allegedly not being mailed notice of the 

draft permit”)). 

Comment A.4: The commenter noted that it appeared EPA was accepting comments only 

regarding the “proposed permit revision” and asked that we identify “the [a]uthority for this 

limitation it feels pi[e]cemeal or bifurcated.” The commenter stated that he would like to 

comment on the entire permit. 

Response A.4: The commenter is correct that only those elements of the permit that EPA 

proposed to revise were open for public comment. We are not addressing comments on other 

elements of the existing PSD permit5

 that remain unaltered, as they are not part of this permitting 

action. As explained in the AAQIR, the proposed revisions do not trigger new PSD 

requirements because they will not result in a significant emissions increase. 40 CFR 

52.21(a)(2)(iv), (b)(2) (referencing definitions of “significant emissions increase” and “net 

emissions increase” in sections 52.21(b)(3), (23) and (40)). In evaluating applications to revise 

PSD permits, however, EPA considers whether the change triggers new requirements and 

whether the requested changes to the permit ensure that the PSD requirements (e.g., BACT and 

protection of ambient air quality standards) continue to be met. This is necessary even if the 

permit limits are exceeded by less than a “significant” amount. See Memorandum from G. 

McCutchen, Chief, NSR Section, to J.D. Sullivan, Chief, ALO Enforcement Section, Region VI 

(Nov. 19, 1987); cf. In re Chehalis, PSD Appeal No. 01-06, slip op. at 27-29 (EAB August 20, 

2001) (noting absence of any controlling statutory or regulatory provision regarding when a 

revised BACT analysis is mandated in the context of PSD amendments to a previously existing 

permit, and finding no clear error or abuse of discretion in permitting authority’s decision not to 

revise the BACT analysis in that case). Accordingly, we evaluated the proposed changes to 

ensure compliance with BACT and other PSD requirements, and we provided an opportunity for 

public comment on the proposed permit revisions consistent with the requirements of 40 CFR 

 

5

 EPA issued the PSD permit for CGS on September 29, 2008, following a public process in 

accordance with the requirements of 40 CFR part 124. 
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

6

part 124. EPA does not currently have a basis for reopening other elements of the permit that are 

unaffected by the proposed changes. 

B. COMMENTS ON BEST AVAILABLE CONTROL TECHNOLOGY (BACT) 

DETERMINATIONS 

Comment B.1: The commenter stated that the CGS’s water bath heater is expected to emit 

carbon monoxide (CO) at 100 parts per million by volume on a dry basis (ppmvd) and that 

“[s]even sources have lower CO emission rates than the CGS’s fuel gas heater, ranging from 27 

to 72 ppmvd.” In support of this assertion, the commenter referenced an e-mail dated April 8, 

2009, from Jerry Salamy (CH2M, consultant to PG&E) to Shaheerah Kelly (EPA Region 9). 

The commenter identified the following permit applications and CO emission rates expressed in 

ppm at 3% oxygen: AES Puerto Rico Cogen application PR-007 (27 ppm, limestone dryer); BP 

Exploration, Inc., Milne Point Production application AK-047 (27 ppm); South Cal Gas 

application SCAQMD AN: 347641 (50 ppm); and Norton Energy Storage, LLC application OH0264 (53 ppm), which the commenter asserted “has been verified in practice.” The commenter 

asserted that “[t]he PSD permit must adopt a lower limit for CO emissions for the Water Bath 

heater.” 

Response B.1: EPA has concluded that the CO emission limitation of 100 ppmvd for the CGS 

water bath heater is consistent with the BACT limits achieved to date by similar units at other 

facilities and, therefore, disagrees with the commenter. It appears that the commenter based his 

assertions on information provided by the applicant in an e-mail to EPA dated May 1, 2009, 

which transmitted the applicant’s BACT analysis for the water bath heater and also attached an 

earlier e-mail dated April 8, 2009. See e-mail dated May 1, 2009, from Jerry Salamy (CH2M, 

consultant to PG&E) to Shaheerah Kelly (EPA Region 9). The attachment to that e-mail 

identified the same facilities that the commenter referenced, together with CO emissions 

limitations ranging from 27 ppm to 112 ppm for various heating devices. Other than simply 

reciting the lower figures among this range of emissions limitations, the commenter provided no 

information to support an argument that the CGS water bath heater is capable of consistently 

achieving any CO emission limitation below 100 ppmvd. 

We have nonetheless independently reviewed the permit limits referenced by the commenter and 

concluded that that none of them compels us to reevaluate the BACT emissions limitations for 

the CGS water bath heater. First, the CO emission limitation of 27 ppm (0.02 lb/MMBtu) for BP 

Exploration (Alaska) Inc. is incorrect. The referenced permit for BP Exploration (Alaska) Inc., 

for the operation of the Milne Point Production Facility, actually contains a CO BACT emission 

limit of 0.2 lb/MMBtu for each heater,6

 which equates to a concentration limit of about 266 

 

6 See Alaska Department of Environmental Conservation, Permit No. 200TVP01, Milne Point 

Production Facility, Section 5, Condition 30 (“Heater CO and NOx BACT Limits”); see also 

“Format RBLC Report, Control Technology Determinations, Milne Point Production Facility, 

RBLC ID: AK-0047,” Heaters, H-5302A and H-5302B (emission limits for carbon monoxide), 

at p. 3 of 15.
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

7

ppm.7 Second, the pre-heater units at the Norton Energy Storage facility, for which the 

commenter identifies a CO emissions limitation of 53 ppm, were never constructed.8 Finally, 

several of the identified heating devices appear to operate differently from the CGS water bath 

heater. For example, the limestone dryer at the AES Puerto Rico facility, which is a coal-fired 

steam electric cogeneration facility, consists of a crusher in which a stream of heated air both 

separates (by size fraction) ground limestone and dries the material.9 The heater units at the 

Southern California Gas Company’s Aliso Canyon Station, which is a natural gas storage field, 

are integrated into dehydration plants that use a liquid absorbent (Triethylene Glycol or TEG) to 

remove moisture from the gas and then regenerate the spent TEG by heating it to boil off the 

absorbed water.10 The CGS water bath heater serves a different function, i.e., maintaining the 

temperature of the natural gas combusted at CGS at approximately 75 degrees (Fahrenheit) to 

minimize operational issues caused by changes in gas temperature.11 In any case, the permit 

limits for AES Puerto Rico and the Aliso Canyon Station do not reveal a CO control method 

other than good combustion practices that could further reduce CO emissions from the CGS 

water bath heater. In the absence of any supporting analyses, the commenter’s mere references 

to the emissions limitations in these other permits do not compel us to change our analysis. 

Best Available Control Technology (“BACT”) is defined as 

an emission limitation based on the maximum degree of reduction of each pollutant subject 

to regulation under this Act emitted from or which results from any major emitting facility, 

which the permitting authority, on a case-by-case basis, taking into account energy, 

environmental, and economic impacts and other costs, determines is achievable for such 

 

7

 For purposes of comparison, we have used the conversion factor used by the applicant in the 

May 1, 2009 e-mail from Jerry Salamy to Shaheerah Kelly (CO ppm = lb/MMBtu X 1330) to 

estimate the ppm emissions rate based on the correct permit limit of 0.2 lb/MMBtu. 

8

 Norton Energy Storage, L.L.C. received a permit in May 2002 authorizing construction of 

several pre-heater units each subject to a CO emissions limitation of 0.040 lb/MMBtu (roughly 

53 ppm, using the conversion factor described in fn. 7, ibid.), but according to Ohio EPA, these 

pre-heater units were never installed. See e-mail dated December 2, 2009, from Laura Miracle 

(Ohio EPA) to Shaheerah Kelly (EPA Region 9), “RE: Norton Energy”; see also Ohio EPA, 

Final Permit to Install Modification, Norton Energy Storage, L.L.C., Facility ID: 1677100033 

(effective May 23, 2002); Ohio EPA, Final Air Pollution Permit-to-Install and Operate for 

Norton Energy Storage, L.L.C., Permit No. 0103955, at pg. 2 (effective November 24, 2008) 

(identifying currently permitted emission units). 

9 See Final Prevention of Significant Deterioration of Air Quality (PSD) Permit for the AES 

Puerto Rico Cogeneration Plant (AES-PRCP), Attachment I: Project Description, available at 

http://www.epa.gov/Region2/air/permit/AES08102004.pdf. 10 See South Coast Air Quality Management District, Permit No. 347641, Southern California 

Gas Company: Aliso Canyon Station, “Process Description”; see also CARB BACT 

Clearinghouse Report for Southern California Gas Company at 

http://www.arb.ca.gov/bact/bactnew/determination.php?var=903. 11 See letter dated November 18, 2008, from Jon Maring (PG&E) to Shaheerah Kelly (EPA 

Region 9), “Pacific Gas and Electric Company Colusa Generating Station, PSD Permit Number: 

SAC 06-01.” 
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

8

facility through application of production processes and available methods, systems, and 

techniques, including fuel cleaning, clean fuels, or treatment or innovative fuel combustion 

techniques for control of each such pollutant. 

Clean Air Act § 169(3), 42 U.S.C. 7479(3); 40 CFR 52.21(b)(12); 40 CFR 51.166(b)(12). 

EPA applies a five-step “top-down” review process in developing PSD permits. The first step is 

to identify all “available” control options for the emissions unit in question—that is, those air 

pollution control technologies or techniques with a practical potential for application to the 

emissions unit and the regulated pollutant under evaluation. The second step of the BACT topdown review process is to eliminate “technically infeasible” options based on source-specific (or 

emissions unit-specific) factors. A demonstration of technical infeasibility should show, based 

on physical, chemical, and engineering principles, that technical difficulties would preclude the 

successful use of the control option on the emissions unit under review. In the third step, all 

remaining control technologies are ranked by control effectiveness for the pollutant under 

review, with the most effective control alternative at the top. The list of control alternatives 

should include, for each alternative, information about control efficiencies, expected emission 

rate, expected emissions reduction, economic impacts, environmental impacts, and energy 

impacts. In the fourth step, the permitting agency evaluates the energy, environmental, and 

economic impacts of each of the listed control options, beginning from the top. If collateral 

environmental impacts justify elimination of the first option, the next most stringent alternative is 

considered. This process continues until the technology under consideration cannot be 

eliminated by any source-specific environmental, energy, or economic impacts that render the 

option inappropriate as BACT. See, e.g., In Re Prairie State Generating Company, LLC, PSD 

Appeal No. 05-05, slip op. at 17-18 (EAB, August 24, 2006), rev. denied, Sierra Club v. EPA, 

499 F.3d 653 (7th Cir. 2007); In Re Newmont Nevada Energy Investment, LLC, 12 E.A.D. 429 at 

435 (EAB 2005); In re Knauf Fiber Glass, 8 E.A.D. 121, 129-31 (EAB 1999); In Re Rockgen 

Energy Center, 8 E.A.D. 536 at 541-42 (EAB 1999).

As the EAB has noted, “[b]ecause BACT is a preconstruction site-specific determination, BACT 

review inherently requires a judgment regarding what can reasonably be expected in the future,” 

but also must be “solidly grounded on what is presently known about the selected technology’s 

effectiveness at controlling pollutant emissions.” In Re Newmont Nevada Energy Investment, 

LLC, 12 E.A.D. 429 at 440 (EAB 2005). The Board has further acknowledged that available 

data on the past performance of a selected technology may show that “the control efficiency 

achievable through the use of the technology may fluctuate so that it would not always achieve 

its optimal control efficiency,” and that application of identical technology may not yield 

identical emission limits at different facilities. Id. at 442. 

EPA does not currently have sufficient data to support a conclusion that the water bath heater 

proposed for the CGS facility can consistently achieve a CO emission limit of less than 100 ppm, 

and the commenter has not provided any such information. A CO emission limitation of 100 

ppm reflects good combustion practices and is within the range of emission limitations for 

comparable heating devices that we have identified in EPA’s RACT/BACT/LAER 

Clearinghouse and in the San Joaquin Valley Air Pollution Control District (SJVAPCD) BACT 
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

9

Clearinghouse.12 Accordingly, we conclude that the proposed 100 ppm emission limit for CO 

represents BACT for the water bath heater. 

Comment B.2: The commenter stated that the CGS’s water bath heater is expected to emit 

nitrogen oxides (NOx) at 30 ppmvd and that “[b]ased on a review of the EPA’s 

RACT/BACT/LAER Clearinghouse, California Air Resources Board Statewide [BACT] 

Clearinghouse, and the San Joaquin Valley Air Pollution Control Districts [BACT] 

Clearinghouse there are 4 sources which report a lower NOx emission rate than the CGS WBH, 

ranging from 9 to 20 ppmv of NOx.” The commenter identified the following sources and 

emission rates expressed in ppm at 3% oxygen: NELCO Products, application SCAQMD AN: 

371784 (12 ppm, force circulation oil heater), and South Cal Gas, application SCAQMD AN: 

347641 (20 ppm, heater). The commenter also asserted that “[t]he SJVUAPCD BACT 

clearinghouse lists [two] BACT determinations of 9 ppm and 12 ppm as BACT for NOx 

emissions from a pre heater,” referencing as support an e-mail dated April 8, 2009, from Jerry 

Salamy (CH2M, consultant to PG&E) to Shaheerah Kelly (EPA Region 9). 

Response B.2: EPA has concluded that the NOx emission limitation of 30 ppmvd for the CGS 

water bath heater is consistent with the BACT limits achieved to date by similar units at other 

facilities and, therefore, disagrees with the commenter. It appears that the commenter based his 

assertions on information provided by the applicant in an e-mail to EPA dated May 1, 2009, 

which transmitted the applicant’s BACT analysis for the water bath heater and also attached an 

earlier e-mail dated April 8, 2009. See e-mail dated May 1, 2009, from Jerry Salamy (CH2M, 

consultant to PG&E) to Shaheerah Kelly (EPA Region 9). The attachment to that e-mail 

identified the same facilities that the commenter referenced, together with NOx emissions 

limitations ranging from 9 ppm to 81 ppm for various heating devices. Other than simply 

reciting the lower figures among this range of emissions limitations, the commenter provided no 

information to support an argument that the CGS water bath heater is capable of consistently 

achieving any NOx emission limitation below 30 ppmvd. 

We have nonetheless independently reviewed the permit limits referenced by the commenter and 

concluded that that none of them compels us to reevaluate the BACT emissions limitations for 

the CGS water bath heater. First, several of the identified heating devices appear to operate 

differently from the CGS water bath heater. For example, the heater at the NELCO Products 

facility, which manufactures plastic panels used in the manufacturing of printed circuit boards, is 

a thermal oil heater rated at 19 MMBtu/hour that is used to heat hot oil circulating inside 

 

12 See, e.g., Format RBLC Report, Crescent City Power, LLC, Crescent City Power, RBLC ID: 

LA-0192 (CO emission limits for Fuel Gas Heaters) and Format RBLC Report, AES Red Oak, 

LLC, AES Red Oak, RBLC ID: NJ-0036 (CO emission limits for fuel gas heater), available at

http://cfpub.epa.gov/RBLC/htm/bl02.cfm; SJVAPCD BACT Clearinghouse at section 1.8.4A 

(CO emission limit for heater treater) and section 1.8.4C (CO emission limit for heater treater), 

available at http://www.valleyair.org/busind/pto/bact/chapter1.pdf. The CARB BACT 

Clearinghouse does not identify CO emissions limits for heating devices that are comparable to 

the CGS heater. See BACT Clearinghouse Search Results, All Districts, Category: Heater-Other 

Process, Pollutant: CO, available at http://www.arb.ca.gov/bact/bactnew/rptpara.htm.
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

10

lamination presses.13 EPA does not currently have information demonstrating that the ultra-low 

NOx burner technology used in this thermal oil heater14 is an available control option for the 

CGS water bath heater, which is rated at 10 MMBtu/hour and is used to maintain the temperature

of the natural gas combusted at CGS at approximately 75 degrees (Fahrenheit) to minimize 

operational issues.15 The heater units at the Southern California Gas Company’s Aliso Canyon 

Station, as discussed in Response B.1 above, are integrated into dehydration plants that use a 

liquid absorbent (TEG) to remove moisture from natural gas and then regenerate the spent TEG 

by heating it to boil off the absorbed water.16 These heating devices also appear to operate 

differently from the CGS water bath heater, although the NOx control method is similar to that 

proposed for CGS, i.e., low-NOx burners and flue gas recirculation.17 In any case, neither of 

these permit limits demonstrates the availability of a NOx control method that could feasibly 

reduce NOx emissions from the CGS water bath heater below 30 ppm. 

Second, the commenter references a NOx emission limitation of 9 ppm in the SJVAPCD’s 

BACT Clearinghouse, but without identifying any particular facility or control method. We have 

reviewed the SJVAPCD’s BACT Clearinghouse and identified a source called Central Valley 

Meat Co. that had applied for a permit containing a NOx emission limit of 9 ppmvd at 3% 

oxygen (0.011 lb-NOx/MMBtu) for a dryer burner.18 According to the SJVAPCD, however, this 

application was denied and the source has not re-applied.19 Finally, the commenter references a 

NOx emission limitation of 12 ppm in the SJVAPCD’s BACT Clearinghouse, again without 

identifying any particular facility or control method. We have reviewed the SJVAPCD’s BACT 

Clearinghouse and identified a source called Occidental of Elk Hills, Inc., that applied for a 

permit containing a NOx emission limit of 12 ppmvd for a non-refinery process heater.20 

According to the SJVAPCD, this unit has not yet demonstrated compliance with the 12 ppm 

NOx limit.21 In the absence of any supporting analyses, the commenter’s mere references to the 

emissions limitations in these other permits do not compel us to change our analysis. 

 

13 See South Coast Air Quality Management District, Permit to Construct, A/N 371784, NELCO 

Prod. Inc., “Process Description.” 14 See CARB BACT Clearinghouse Report for NELCO Products, Inc., at 

http://www.arb.ca.gov/bact/bactnew/determination.php?var=685. 15 See letter dated November 18, 2008, from Jon Maring (PG&E) to Shaheerah Kelly (EPA 

Region 9), “Pacific Gas and Electric Company Colusa Generating Station, PSD Permit Number: 

SAC 06-01.” 

16 See South Coast Air Quality Management District, Permit No. 347641, Southern California 

Gas Company: Aliso Canyon Station, “Process Description.” 

17 See CARB BACT Clearinghouse Report for Southern California Gas Company at 

http://www.arb.ca.gov/bact/bactnew/determination.php?var=903. 18 See SJVAPCD BACT Clearinghouse, http://www.valleyair.org/busind/pto/bact/chapter1.pdf, 

at section 1.9.13. 19 See e-mail dated December 2, 2009, from Jim Swaney (SJVAPCD) to Shaheerah Kelly (EPA 

Region 9), “RE: Request for BACT/Permit information.” 

20 See SJVAPCD BACT Clearinghouse, http://www.valleyair.org/busind/pto/bact/chapter1.pdf, 

at section 1.8.5. 

21 See e-mail dated March 2, 2010, from Jim Swaney (SJVAPCD) to Shaheerah Kelly (EPA 

Region 9), “RE: Request for BACT/Permit information.” 
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

11

In sum, EPA does not currently have sufficient data to support a conclusion that the water bath 

heater proposed for the CGS facility can consistently achieve a NOx emission limit of less than 

30 ppm, or that pollution control technologies other than low-NOx burners are feasible for this 

heater, and the commenter has not provided any such information to support his assertion. A 

NOx limit of 30 ppm based on low-NOx burner technology is within the range of emission 

limitations for comparable heating devices that we have identified in EPA’s 

RACT/BACT/LAER Clearinghouse and in SJVAPCD’s BACT Clearinghouse.22 Accordingly, 

we conclude that the proposed 30 ppm emission limit for NOx represents BACT for the water 

bath heater. See also Response B.1. above. 

Comment B.3: The commenter stated that because the applicant is removing the auxiliary 

boiler, EPA’s statement of basis “needs to evaluate the impact and BACT for startup and 

shutdowns times and emissions.” Specifically, the commenter stated that according to the July 

12, 2006 application, this natural gas-fired auxiliary boiler rated at 44 million BTU/hr was to be 

“included to provide steam to shorten the time required for plant starts,” and that EPA “must 

require the project to meet lower startup and shut down times and emissions since they are 

allowing removal of the auxiliary Boiler....” The commenter also alleged that the permit’s 

current startup/shutdown limits do not meet BACT requirements, and that combined cycle 

turbines currently being permitted can achieve cold, warm, and hot starts taking no longer than 1 

hour to meet normal steady state emission limits. The commenter asserted that these “fast start 

machines are now being utilized in most new power plant applications such as the new proposed 

Contra Costa Generating Plant, the Willow Pass Generating Station and the Marsh Landing 

Project.” The commenter provided information about the technologies and emission rates 

associated with each of these three facilities and asserted that “EPA in a recent consent decree 

with PG&E has required fast start technology on GE Frame 7 machines the same equipment used 

at Colusa.” The commenter asserted that startup and shutdown emission rates “are much greater 

than steady state emissions for NOx and CO therefore, BACT for NOx emitted during startup 

and shutdown is not covered by the steady-state NOx Top-Down Analysis.” Finally, the 

commenter identified and described the GE “OpFlex” and “Rapid Response” technologies as two 

“possible control technologies [that] could be utilized.” 

Response B.3: We are not revising the BACT emission limits in the PSD permit for startup and 

shutdown periods as part of this permitting action, and we have no information indicating that 

the changes to the CGS facility design render the existing permit limits for startup and shutdown 

operations unachievable. To the extent the commenter intended to argue that removal of the 

auxiliary boiler from the facility design requires a reevaluation of the permit conditions for 

 

22 See, e.g., Format RBLC Report, Crescent City Power, LLC, Crescent City Power, RBLC ID: 

LA-0192 (NOx emission limits for Fuel Gas Heaters) and Format RBLC Report, Port 

Washington Generating Station, RBLC ID: WI-0227 (NOx emission limits for Gas Heater), 

available at http://cfpub.epa.gov/RBLC/htm/bl02.cfm; SJVAPCD BACT Clearinghouse at 

section 1.6.16 (NOx emission limit for Dryer – Seed Processing), section 1.6.21A (NOx 

emission limit for natural-gas fired, conveyor-fed, flake cereal dryer), section 1.6.21 (NOx 

emission limit for flake cereal dryer), and section 1.9.9 (NOx emission limit for natural gas fired 

paper products dryer), available at http://www.valleyair.org/busind/pto/bact/chapter1.pdf. 
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

12

startup and shutdown operations, these arguments are unsupported.23 To the extent the 

commenter intended to challenge the startup and shutdown limits in the initial PSD permit, 

which became final and effective on September 29, 2008, these arguments are late and are 

outside the scope of our current action. See Response A.4 above. The commenter has provided 

no justification for his late challenge to this prior action. We note also that it is not unusual for a 

permit applicant to make minor changes in engineering design during the construction phase and 

to request corresponding permit revisions to accommodate such changes. 

Comment B.4: The commenter asserted that the PSD analysis must include an evaluation of 

BACT to control PM2.5 emissions. The commenter quoted from EPA’s discussion of PM2.5 

emissions in the statement of basis for the initial PSD permit EPA proposed for comment in May 

2008 (May 2008 AAQIR), which stated that the review of PM10 emissions would serve as a 

surrogate for review of PM2.5 emissions consistent with EPA policy at that time. The 

commenter asserted that “EPA has decided to repeal its recently adopted provision in 40 C.F.R. 

52.21(i)(1)(xi) that directs permitting agencies to use the so called surrogate approach in 

addressing PM2.5 compliance issues.” 

Response B.4: EPA disagrees with the commenter’s assertion that EPA is required to evaluate 

BACT for PM2.5 emissions as part of this permit action. First, to the extent the commenter 

intended to challenge the rationale in EPA’s May 2008 AAQIR for treating the review of PM10 

emissions as a surrogate for review of PM2.5 emission, this challenge is late. EPA issued the 

final PSD permit for CGS on September 29, 200824, and the 30-day period within which 

challenges to that action could be brought under 40 CFR part 124 expired on October 30, 2008. 

The commenter has provided no justification for his late challenge to this prior action. Second, 

as to the current permitting action, we explained in the AAQIR that the proposed changes to the 

source do not trigger new PSD requirements because they will not result in a significant net 

emissions increase as defined in 40 CFR 52.21(b)(3) and (23). We also explained that the 

proposed changes would significantly reduce the source’s annual and hourly emissions of both 

PM and PM10. See AAQIR at pp. 3 and 6. As a technical matter, the substantial reductions in 

PM/PM10 emissions resulting from the proposed changes will include reductions in the facility’s 

 

23 We note that the performance testing requirements in the permit remain unchanged. See 

Condition X.F of initial PSD permit and Amended PSD Permit. If EPA determines based on 

source testing data that the startup and shutdown BACT emission limits in the permit are not 

achievable, EPA will reevaluate these permit conditions, as well as the air quality impact 

analyses based on these emission limits. See AAQIR for initial PSD permit (May 2008 AAQIR) 

at pg. 20. 

24 As of this date, under a provision commonly referred to as the PSD “grandfathering provision” 

for PM2.5, permit applicants who had submitted complete PSD permit applications prior to July 

15, 2008 were specifically exempted from PSD requirements as applied to PM2.5. 40 CFR 

52.21(i)(1)(xi) (2008). EPA determined that the CGS’s permit application was complete on 

March 14, 2007. See Administrative Completeness letter for PSD application from Gerardo 

Rios, Chief, Permits Office, EPA Region 9, to Andrew Welch, Project Manager, E&L 

Westcoast, LLC (March 14, 2007). As such, the CGS’s initial PSD permit was exempt from 

PM2.5 PSD requirements under the regulations that were in effect at the time of permit issuance. 
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

13

PM2.5 emissions, which are a subset of PM/PM10. Absent a significant net emissions increase 

in PM2.5 emissions, PSD requirements for PM2.5 emissions do not apply. 

The commenter references EPA’s recent statements about the use of PM10 as a surrogate for 

PM2.5 in PSD permitting actions. It appears that the commenter is referring to EPA’s decision 

to stay the provision in 40 CFR 52.21(i)(1)(xi) (the “grandfathering” provision for PM2.5) that 

allows permit applicants who had submitted complete PSD permit applications prior to July 15, 

2008 to continue using PM10 analyses as surrogates for PM2.5 analyses. EPA administratively 

stayed this provision effective June 1, 2009 (74 FR 26098; see also 74 FR 48153, extending stay 

to June 22, 2010) and has recently proposed to repeal the provision entirely. 75 FR 6827 

(February 11, 2010). We note first that the Agency has not yet taken final action on this proposal. 

In any case, EPA is not interpreting its proposed repeal of the grandfathering provision to have 

any effect on permits that became final and effective before the June 1, 2009 stay of section 

52.21(i)(1)(xi) by the Administrator. 75 FR at 6833. As stated above, EPA issued the final PSD 

permit for CGS on September 29, 2008, prior to the Administrator’s June 1, 2009 stay of the 

PSD grandfathering provision for PM2.5. Accordingly, this proposed action has no effect on the 

CGS’s initial PSD permit. 

In sum, to the extent the commenter intended to argue that EPA was required to evaluate PM2.5 

emissions as part of the CGS’s initial PSD permit, which became final and effective on 

September 29, 2008, that argument is late and in any case has no merit for the reasons stated 

above. To the extent the commenter intended to argue that EPA is required to evaluate PM2.5 

emissions as part of the current permit revision, this argument also has no merit, because the 

changes do not result in any significant emissions increase as defined in 40 CFR 52.21(b)(40) 

(see 40 CFR 52.21(a)(2)(iv)). As such, EPA is not required to evaluate BACT or any other PSD 

requirement as applied to PM2.5 emissions as part of this permitting action. 

C. COMMENTS ON ANALYSIS OF SOURCE IMPACTS ON AIR QUALITY 

Comment C.1: The commenter asserted that the PSD air quality impact analysis must contain a 

demonstration that the CGS facility “will not contribute to an exceedance of the PM2.5 NAAQS 

for annual and 24 hour standards.” In support of this assertion, the commenter provided excerpts 

from the discussion in EPA’s AAQIR of the reasons why this permit revision did not require a 

reevaluation of EPA’s prior air quality modeling analyses, and asserted that “EPA never 

examined PM2.5 ambient air [quality] impacts in the 2008 [statement of basis].” The commenter 

also quoted from EPA’s discussion of PM2.5 emissions in the May 2008 AAQIR, which stated 

that the review of PM10 emissions would serve as a surrogate for review of PM2.5 emissions 

consistent with EPA policy at that time, and asserted that “EPA has decided to repeal its recently 

adopted provision in 40 C.F.R. 52.21(i)(1)(xi) that directs permitting agencies to use the so 

called surrogate approach in addressing PM2.5 compliance issues.” Additionally, the commenter 

stated that “[w]hile the project has proposed a reduction in PM2.5 emissions the change in the 

physical configuration has led to higher ambient air concentrations for PM2.5,” and that “[t]he 

projects PM2.5 ambient air quality impact change from 2.73 ug/m3 in the original FDOC to 3.3 

ug/m3 with the projects modifications triggering an assessment of the project PM2.5 impacts 

under the new EPA PM2.5 regulations.” In support of these assertions, the commenter 
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

14

referenced the Final Determination of Compliance issued by the CCAPCD to PG&E in June 

2007 and the petition for license amendment submitted by PG&E to the CEC in August 2008. 

Response C.1: We disagree with the commenter’s assertion that EPA is required to evaluate 

PM2.5 ambient air quality impacts as part of this action. See Response B.4 above. The 

commenter’s assertion that the proposed changes will result in increased ambient concentrations 

of PM2.5 is unsupported, and his references to the CCAPCD’s Final Determination of 

Compliance (FDOC) and materials submitted by the applicant to the CEC pursuant to CEC 

licensing requirements are outside the scope of our action. EPA is issuing this PSD permit 

pursuant to the federal requirements in Section 165 of the CAA and EPA’s implementing 

regulations in 40 CFR 52.21 and part 124. 40 CFR 52.21(q). The CCAPCD and CEC 

implement state and local requirements, which do not govern EPA’s permit action. 

Comment C.2: The commenter asserted that EPA’s nitrogen deposition analysis is defective 

because it relies on the assessment provided in the applicant’s 2006 PSD permit application, 

which did not include nitrogen deposition impacts from the project’s ammonia emissions. The 

commenter asserted that the CGS facility will emit 159 tpy of ammonia and that these emissions 

will have a larger impact than the project’s NOx (including NO2) or SO2 emissions. The 

commenter also stated that “the original nitrogen deposition analysis” did not include the impacts 

from the Delevan Compressor Station. 

Response C.2: It appears the commenter is challenging the adequacy of the soils and vegetation 

analyses that EPA provided in the May 2008 AAQIR. See May 2008 AAQIR, section 10.2 

(discussing applicant’s analysis of the potential effects of NO2 and SO2 emissions from the 

source as well as estimates of total nitrogen deposition). These challenges are late. As we have 

noted above, EPA issued the final PSD permit for CGS on September 29, 2008, and the period 

within which challenges to that action could be brought has long expired. The commenter has 

provided no justification for his late challenge to this prior action. 

To the extent the commenter intended to argue that EPA is required to reevaluate the effects of 

nitrogen deposition as part of the AAQIR for the Draft Amended Permit, this argument has no 

merit. As we explained in the AAQIR, the proposed permit revisions do not alter any of the 

assumptions underlying our prior analyses of air quality and additional impacts. AAQIR at 4. In 

fact, because the proposed revisions reduce the facility-wide emission limits for all pollutants 

covered by the permit and significantly reduce the annual and short-term emission limitations for 

PM and PM10, our prior analyses of air quality and additional impacts are even more 

conservative (i.e., overestimated) than they were for the initial PSD permit. Finally, the 

comment about impacts from the Delevan Compressor Station (DCS) is outside the scope of this 

permitting action as the DCS is not covered by this Draft Amended Permit. See Response C.3 

below. 

Comment C.3: The commenter stated that “the modification of the CGS triggers the adjustment 

of baseline emissions to include the adjacent Delevan compressor Station.” The commenter 

asserted that the Delevan compressor station has NOx emissions of 356 tpy and that these 

emissions, added to the CGS facility’s emission, would amount to 540 tpy of NOx on “adjacent 

parcels owned and operated by PG&E connected by a common pipeline,” which “equates to 1.47 
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

15

tons per day of NOx emissions from the same company PG&E.” The commenter asserted that 

the combined NOx emissions from the CGS and the Delevan compressor station “must be 

included in the soils and vegetation analysis to determine if there are any significant impacts to 

biological and agricultural resources.” Apparently in support of these assertions, the commenter 

pasted an excerpt from EPA’s description of the nearby Delevan compressor station in the May 

2008 AAQIR. 

Response C.3: First, to the extent the commenter intended to argue that emissions from the 

Delevan Compressor Station (DCS) should be treated as emissions of the source under this Draft 

Amended Permit, this is incorrect. The PSD program applies to any “new major stationary 

source” or “major modification” to an existing source as those terms are defined in 40 CFR 

52.21(b). 40 CFR 52.21(a)(2)(ii). The existing DCS is neither part of the new major stationary 

source authorized by the initial PSD permit nor part of any major modification to an existing 

source. As such, the DCS is not subject to PSD requirements. 

Second, the commenter’s reference to EPA’s discussion of the DCS in the May 2008 AAQIR 

appears to rest on an incorrect understanding of that discussion. EPA stated in the May 2008 

AAQIR that the DCS and the CGS would be treated as a single source for purposes of title V 

operating permit requirements. See May 2008 AAQIR at pg. 7. This has no bearing on the PSD 

analysis, as title V permits implement separate CAA authorities. EPA also stated in the May 

2008 AAQIR that if the CGS facility were subsequently modified, the source’s “baseline actual 

emissions” under 40 CFR 52.21(b)(48) would comprise emissions from both the CGS and the 

DCS. Id. This will be true after the source begins normal operations, at which point it will be 

required to calculate the emissions increase resulting from any source modification in accordance 

with the definitions of “baseline actual emissions” (§ 52.21(b)(48)) and “projected actual 

emissions” (§52.21(b)(41)) or “potential to emit” (§ 52.21(b)(4)), as applicable. 40 CFR 

52.21(a)(2)(iv).25 Thus, the discussion in our May 2008 AAQIR addresses requirements that 

may apply to the DCS if the CGS facility seeks to modify after it begins normal operations. It 

does not affect our analysis for the current permit revision, which is designed to ensure that the 

PSD requirements that applied to the initial construction authorization continue to be satisfied. 

See Response A.4 above. As such, the commenter’s assertion that the DCS should be included 

in our current PSD analysis is incorrect. 

Finally, to the extent the commenter intended to challenge the adequacy of the soils and 

vegetation analyses that EPA provided in the May 2008 AAQIR, this challenge is late. See

Response C.2 above. 

D. COMMENTS ON ENDANGERED SPECIES ACT (ESA) CONSULTATION 

PROCESS 

Comment D.1: The commenter asserted that consultation with the U.S. Fish & Wildlife Service 

(FWS) must be reinitiated to address the project’s impacts on the Swainson’s Hawk. The 

commenter stated that the applicant had recently requested an amendment to its CEC license “to 

 

25 Currently, because the source has not yet begun normal operations, emissions are calculated 

based on the source’s potential to emit. 40 CFR 52.21(b)(21)(iv). 
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

16

allow slight modification of the size and layout of the switchyard and the electric transmission 

interconnection route.” The commenter stated that the “CEC final decision approved a total of 

12 new towers, four on site (within the 100 acre parcel and eight offsite[)],” and that “[t]he 

applicant’s new proposal will add a total of 20 new towers with eight on site and 12 offsite.” 

The commenter stated that “[a]s stated on page 2-2 of the amendment, ‘Construction of the new 

towers has the potential to slightly increase permanent impacts to Swainson’s hawk foraging 

habitat,’” that “[t]he reconfigured switchyard/substation will result in an additional 0.87 acre of 

disturbance of annual grassland,” and that “[t]he two project component changes will result in a 

total of 1.15 acres of additional impacts to annual grassland beyond what was originally 

permitted in the CEC’s Final Decision for the CGS project.’” The commenter provided excerpts 

from the May 2008 AAQIR and asserted that “[t]he Biological opinion did not include impacts 

and mitigation for the Swainson hawk.” In sum, the commenter stated that “[n]either the original 

biological opinion nor the current [AAQIR] has analyzed the impacts from the placement of six 

new transmission towers or the realignment of the original transmission towers.” The 

commenter referenced 50 CFR § 402.1(3) in support of these assertions. 

Response D.1: These arguments have no merit. ESA section 7 consultation requirements do not 

currently apply to the Swainson’s hawk because it is not a listed species under the Federal ESA. 

See U.S. Fish and Wildlife Service (FWS), Species Profile for Swainson’s hawk (Buteo 

swainsoni) at http://ecos.fws.gov/speciesProfile/profile/speciesProfile.action?spcode=B070. We 

note that EPA contacted the FWS to discuss the potential need for additional consultation as a 

result of the proposed permit revisions. Specifically, we evaluated the proposed changes to the 

CGS design and determined that issuance of this amended PSD permit would have no effect on 

federally listed endangered species or critical habitats. We provided our analysis to the FWS and 

requested a response as to whether the FWS objected to our conclusion. In response, the FWS 

confirmed that it would not need to amend the Biological Opinion issued on March 14, 2008 for 

the CGS's initial construction authorizations. See e-mail dated August 13, 2009, from Michelle 

Tovar, FWS, to Shaheerah Kelly, EPA Region 9, “Re: ESA Consultation for Colusa Generating 

Station.” As such, EPA has satisfied its obligations under the ESA for this permit. Finally, the 

commenter’s assertions about the CEC license and the applicant’s petition to amend the license 

are outside the scope of this permitting action. EPA is issuing this PSD permit pursuant to the 

federal requirements in Section 165 of the CAA and EPA’s implementing regulations in 40 CFR 

52.21 and part 124. 40 CFR 52.21(q). The CEC implements State law, which does not govern 

EPA’s permit action. 

Comment D.2: The commenter stated that the applicant’s addition of the wet surface air cooler 

(WSAC) unit will increase operational water use by 21 acre feet per year (AFY), from 130 AFY 

to 151 AFY, and asserted that the implications and environmental impact of this additional water 

usage should be discussed in EPA’s statement of basis. The commenter also asserted that “[t]he 

applicant’s agreement with the Glen-Colusa Water District guarantees 130 AFY for the project 

but any additional water is subject to the water shortage provisions in Article 9A of the 

agreement.” 

Response D.2: These arguments have no merit. Neither the CAA nor EPA’s implementing 

regulations requires EPA to evaluate the impacts of water usage in the statement of basis 

(AAQIR) for this Draft Amended Permit, and the commenter identifies no such support for his 
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

17

contention. EPA has, however, evaluated these potential impacts as part of its ESA consultation 

process with the FWS. Based on the information EPA provided to the FWS about the project’s 

water usage, the FWS confirmed that it would not need to amend the Biological Opinion issued 

on March 14, 2008 for the CGS's initial construction authorizations. See e-mail dated August 13, 

2009, from Michelle Tovar, FWS, to Shaheerah Kelly, EPA Region 9, “Re: ESA Consultation 

for Colusa Generating Station.” The commenter’s assertion about the applicant’s agreement 

with the Glen-Colusa Water District is outside the scope of this permitting action, as that 

agreement is not subject to PSD. 

E. OTHER COMMENTS 

Comment E.1: The commenter requested that EPA inform him of whether this permit revision 

“includes an extension of the permit term” or when the permit expires. The commenter further 

asserted that “this modification (while not disclosed in the public notice) appears to constitute an 

extension of the 18 month commencement of construction deadline found in 40 CFR 52.21 and 

so it should be disclosed as such in the public notice and be processed consistent with ‘EPA 

Region IX Policy on PSD Permit Extensions Dated September 8, 1988....” 

Response E.1: These arguments have no merit. The commenter appears to be referring to the 

provision in 40 CFR 52.21(r)(2) that states that a PSD permit “shall become invalid if 

construction is not commenced within 18 months after receipt of such approval, if construction is 

discontinued for a period of 18 months or more, or if construction is not completed within a 

reasonable time.” The purpose of this provision is to ensure that sources constructed long after 

receipt of a PSD permit are reevaluated in accordance with current BACT requirements. EPA 

issued the PSD permit for CGS on September 29, 2008, and the permittee commenced 

construction of the CGS facility on October 1, 2008,26 well within the 18-month commencement 

of construction deadline in section 52.21(r)(2). The permittee has no need for an extension of 

the18-month commencement of construction deadline and, indeed, EPA did not propose any 

such extension in the Draft Amended Permit. Accordingly, the EPA policy document on PSD 

permit extensions that the commenter references is not relevant to this action. 

Comment E.2: The commenter stated that this permit “appears to be based upon a PSD 

application which was received by Region 9 on December 22, 2006,” and that “[t]his data 

appears to be outdated.” 

Response E.2: This generalized statement lacks sufficient specificity for EPA to provide a 

meaningful response. Moreover, this permit revision is based upon an application for permit 

revision that EPA received on November 24, 2008, not December 22, 2006. The commenter’s 

assertion is unsupported.

 

26 See letter dated August 26, 2009, from Jon Maring (PG&E) to Director, Air Division (EPA 

Region 9), “RE: Pacific Gas and Electric Company Colusa Generating Station, PSD Permit 

Number SAC 06-01.” As of March 2010, construction on the CGS is 74% complete, according 

to the CEC website. See http://www.energy.ca.gov/sitingcases/all_projects.html#construction. 
Colusa Generating Station - Response to Comments March 19, 2010 

Amended PSD Permit No. SAC 06-01 

18

Comment E.3: The commenter stated that “[i]t appears that comments were received from 

CARE then withdrawn on the original permit after some settlement with CARE. I hereby submit 

those comments of CARE as my own at this time.” 

Response E.3: This generalized statement lacks sufficient specificity for EPA to provide a 

meaningful response. Moreover, part 124 states that materials submitted in support of comments 

“shall be included in full and may not be incorporated by reference, unless they are already part 

of the administrative record in the same proceeding, or consist of State or Federal statutes and 

regulations, EPA documents of general applicability, or other generally available reference 

materials.” 40 CFR 124.13. Comments that EPA received during the public comment period on 

the initial PSD permit are neither part of the administrative record for this action nor properly 

treated as generally available reference materials. As such, the commenter cannot incorporate by 

reference those public comments into this proceeding. 

Comment E.4: The commenter stated that “[i]t appears that greenhouse gases were not 

adequately analyzed for the original permit or the modification,” and that he “would like to 

understand what greenhouse gases will be emitted, [and whether] the EPA considers them 

subject to regulation and comment.” In what appears to be a related argument, the commenter 

asserted that he recalled no response to his previous inquiries regarding this facility, which 

“would seem to discourage public participation,” and that “[w]hile the polluters appear to enjoy 

unbridled cooperation even the Remand from the EAB has not encouraged regulators to respond 

to the public.” The commenter further asserted that the public would “likely be interested” if 

they were informed of the effects of this plant through outreach, that he did not have the 

“expertise or resources to participate to a degree that other organizations have in other PSD 

permits,” and that “[i]f the other organizations that have participated in other PSD permits in the 

region received Notice of this proceeding they may participate.” 

Response E.4: First, as to the comments about greenhouse gases, EPA interprets the definition 

of “regulated NSR pollutant” in 40 CFR § 52.21(b)(50) to exclude pollutants for which EPA 

regulations only require monitoring or reporting, but to include each pollutant subject to either a 

provision in the CAA or a regulation adopted by EPA under the CAA that requires actual control 

of emissions of that pollutant. See Memorandum from Stephen L. Johnson, Administrator, EPA, 

to Regional Administrators, “RE: EPA’s Interpretation of Regulations that Determine Pollutants 

Covered By Federal Prevention of Significant Deterioration (PSD) Permit Program” (December 

18, 2008). Since there are presently no EPA regulations limiting emissions of greenhouse gases, 

we are not currently establishing limitations on greenhouse gases in PSD permits for sources that 

emit these substances. Accordingly, we have not evaluated greenhouse gases either in CGS’s 

initial PSD permit or in this amended permit. 

We note, however, that EPA is moving forward in a careful and deliberate manner to fashion a 

reasonable and common-sense approach to address greenhouse gases emissions and climate 

change. See 74 FR 49454 (September 28, 2009) (Proposed Rulemaking To Establish Light-Duty 

Vehicle Greenhouse Gas Emission Standards and Corporate Average Fuel Economy 

Standards); 74 FR 55292 (October 27, 2009) (Prevention of Significant Deterioration and Title V 

Greenhouse Gas Tailoring Rule, Proposed Rule); 74 FR 56260 (October 30, 2009) (Mandatory 

Reporting of Greenhouse Gases, Final Rule). 
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Amended PSD Permit No. SAC 06-01 

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Second, as to the commenter’s apparently related arguments about inadequacy in EPA’s public 

process on the Draft Amended Permit, see Responses A.1, A.2, and A.3 above. 

Comment E.5: The commenter stated that the revised permit reduces the facility’s hourly PM2.5 

emissions from 20 pounds per hour (lb/hr) to 13.5 lb/hr and asserted that “[t]his is an 

administrative change as no new pollution control equipment or operating changes are being 

proposed.” The commenter also asserted that the permit “fails to establish a basis for these 

reductions and they appear to lower the projects PM2.5 emission to address the project’s 

[exceedance] of the 5% FLAG level of concern for visibility at the Yolla Bolly-Middle Eel 

Wilderness Area.” Apparently in support of these assertions, the commenter quoted extensively 

from an EPA policy document on “sham permits” under the New Source Review permit 

program. 

Response E.5: These arguments have no merit. First, we assume the commenter intended to 

reference the permit conditions and evaluations related to PM and PM10, rather than PM2.5, as 

the permit does not contain any requirements specific to PM2.5. See Response B.4 above. EPA 

believes the substantial reductions in the emission limitations for PM and PM10 in permit are 

environmentally beneficial and permissible under the CAA and its implementing regulations. 

The AAQIR and Draft Amended Permit describe the proposed new equipment and provide our 

evaluation of the applicable requirements, including BACT and ambient air quality impact 

analyses. As the commenter’s generalized references to the EPA policy document on sham 

permits lack sufficient specificity for EPA to provide a meaningful response, we decline to 

address those references. We note, however, that all conditions of this PSD permit are 

enforceable by EPA and by citizens under section 304 of the CAA. 

Comment E.6: The commenter referenced CCAPCD Rule 2.6(c)7 and asserted that this rule 

“requires that ‘The owner or operator of a proposed new or modified source shall to the 

satisfaction of the APCO that all major stationary sources owned or operated by such person (or 

by an controlling, controlled by, or under common control with such person) in California which 

are subject to emission limitations are in compliance or on a schedule of compliance with all 

applicable emission limitations and standards.’” The commenter stated that PG&E owns a 

facility in Contra Costa County called the Gateway Generating Station, which is currently 

“undergoing compliance review at the [CEC]” and “is the subject of an FNOV and a proposed 

consent decree,” and that this facility “is not in compliance with State and Federal Air Quality 

Regulations and will not be in compliance until the activities required by the consent decree are 

completed.” In conclusion, the commenter asserted that this PSD permit cannot be approved 

until PG&E “completes the requirements of the consent decree and comes into compliance with 

these new air quality requirements.” 

Response E.6: These arguments have no merit. EPA is issuing this PSD permit pursuant to the 

federal requirements in Section 165 of the CAA and EPA’s implementing regulations in 40 CFR 

52.21 and part 124. The rule that the commenter references (CCAPCD Rule 2.6(c)7) is a local 

requirement that is not relevant to this action. 
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Amended PSD Permit No. SAC 06-01 

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Comment E.7: The commenter requested that EPA “consider these comments and decline the 

permit or recirculate the draft permit after addressing these comments.” 

Response E.7: EPA disagrees for the reasons stated above. 

III. Administrative Corrections 

EPA has made the following administrative corrections to the Draft Amended Permit: 

1. Project Description: EPA is eliminating the minor revisions to this paragraph that we had 

proposed to make in the Draft Amended Permit, as the proposed revisions were not 

necessary. Thus, the project description remains unchanged from description in the 

initial PSD permit issued on September 29, 2008. 

2. Permit condition X.D.1: EPA corrected the VOC limit from 47.4 tpy to 47.5, which is in 

accordance with PG&E’s permit application. The 47.4 tpy figure in the Draft Amended 

Permit was a typographical error. 

3. Permit condition X.H: EPA removed the reference to Subpart IIII of the New Source 

Performance Standards (NSPS), which apply to compression ignition internal combustion 

engines. The provisions of Subpart IIII do not apply to CGS because the diesel 

emergency generator has been removed from the facility design.