AMENDED 

PREVENTION OF SIGNIFICANT DETERIORATION PERMIT 

ISSUED PURSUANT TO THE 

REQUIREMENTS OF 40 CFR § 52.21 

U.S. ENVIRONMENTAL PROTECTION AGENCY, REGION 9 

PSD PERMIT NUMBER: SAC 06-01 

PERMITTEE: Pacific Gas & Electric Company 

915 Highland Point Drive, Suite 130 

Roseville, CA 95678 

FACILITY NAME: Colusa Generating Station 

FACILITY LOCATION: On approxima!ely 31-acres within a 100-acre 

parcel of agricultural land north of the City of 

Williams, in Colusa County, California 

(Section 35, Township 18N, Range 4W) 

Pursuant to the provisions ofthe Clean Air Act (CAA), Subchapter I, Part C (42 U.S.C. Section 

7470,et. seq.), and the Code of Federal Regulations (CFR) Title 40, Section 52.21, the United 

States Environmental Protection Agency Region 9 (EPA) is issuing an Amended Prevention of 

Significant Deterioration (PSD) air quality permit to the Pacific Gas & Electric Company 

(PG&E). This Amended PSD Permit revises the PSD permit issued to PG&E on September 29, 

2008, for the construction and operation of a new 660 mega-watt (MW) combined cycle power 

plant called Colusa Generating Station (CGS), in Colusa County, California. 

PG&E is authorized to construct and operate the CGS power plant as described herein, in 

accordance with the permit application as revised (and plans submitted with the permit 

application), the federal PSD regulations at 40 CFR § 52.21, and other terms and conditions set 

forth in this Amended PSD Permit. Failure to comply with any condition or term set forth in this 

Amended PSD Permit will be grounds for enforcement action pursuant to Section 113 of the 

Clean Air Act. This permit does not relieve CGS from the obligation to comply with applicable 

federal, state, and Colusa County Air Pollution Control District air pollution control rules and 

regulations. 

This Amended PSD Permit becomes effective 30 days after the date of issuance pursuant to 40 

CFR § 124.15(b). 

3-(1//0 i 

Date 
COLUSA GENERATING STATION 

PREVENTION OF SIGNIFICANT DETERIORATION PERMIT 

AMENDED PERMIT CONDITIONS 

PSD Permit No.: SAC 06-01 

PROJECT DESCRIPTION 

The Colusa Generating Station (CGS) will consist oftwo combustion turbine generators (CT), 

each vented to a heat recovery steam generator (HRSG). The facility will also consist of a single 

condensing reheat steam turbine generator (STG), dry cooling tower technology, and other 

associated equipment. Each HRSG will be equipped with a duct burner. Each of the CTs will be 

equipped with dry low NOx (DLN) combustors. The facility will install selective catalytic 

reduction (SCR) and oxidation catalyst systems. Pacific Gas & Electric Company (Permittee) 

will construct and operate CGS. The project is subject to the PSD program for nitrogen oxides 

(NOx), carbon monoxide (CO), volatile organic compounds (VOC), particulate matter (PM), and 

particulate matter less than 10 microns (PMIO). 

EQUIPMENT DESCRIPTION 

Emission Unit Id. Description 

EU-l One (1) natural gas-fired CT generator rated at 172 MW, vented to a 

HRSG with a 688 MMBtulhr duct burner 

EU-2 , One (1) natural gas-fired CT generator rated at 172 MW, vented to a 

HRSG with a 688 MMBtulhr duct burner 

EU-3 One (1) natural gas-fired 10 MMBtulhr water bath heater 

EU-4 One (1) 8,000 gpm wet surface air cooler 

PERMIT CONDITIONS 

I. Permit Expiration 

As provided in 40 CFR 52.21 (r), this PSD Permit shall become invalid if construction: 

A. is not commenced (as defined in 40 CFR 52.21 (b)(9)) within 18 months after the 

approval takes effect; or 

B. is discontinued for a period of 18 months or more; or 

C. is not completed within a reasonable time. 

II. Permit Notification Requirements 

Permittee shall notify EPA Region 9 in writing or by electronic mail of the: 

A. date construction is commenced, postmarked within 30 days of such date. 

Colusa Generating Station 

Amended PSD Permit 1 

March 19, 2010 

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B. actual date of initial startup, as defined in Condition X.E. 7., postmarked within 15 

days of such date. 

C. date upon which initial performance tests will commence, in accordance with the 

provisions of Condition X.F .1., postmarked not less than 30 days prior to such 

date. Notification may be provided with the submittal of the performance test 

protocol required pursuant to Condition X.F.2. 

D. date upon which initial performance evaluation of the CEMS will commence in 

accordance with 40 CFR 60. 13 (c), postmarked not less than 30 days prior to such 

date. Notification may be provided with the submittal of the CEMS performance 

test protocol required pursuant to Condition X.C.6. 

III.· Facility Operation 

At all times, inCluding periods of startup, shutdown and malfunction, Permittee shall, to 

the extent practicable, maintain and operate the facility including associated air pollution 

control equipment in a manner consistent with good air pollution control practice for 

minimizing emissions. Determination of whether acceptable operating and maintenance 

procedures are being used will be based on information available to the EP A which may 

include, but is not limited to, monitoring results, opacity observations, review of 

operating maintenance procedures and inspection of the source. 

IV. Malfunction Reporting 

A. Permittee shall notify EPA by facsimile or electronic mail at R9.AEO@epa.gov 

within two (2) working days following the discovery of any failure of air pollution 

control equipment, process equipment, or of a process to operate in a normal 

manner, which results in an increase in emissions above the allowable emission 

limits stated in Section X.D. of this permit. 

B. In addition, Permittee shall notify EPA in writing or electronic mail within fifteen 

(15) days of any such failure described under Condition IV.A. The notification 

shall include a description of the malfunctioning equipment or abnormal 

operation, the date of the initial malfunction, the period of time over which 

emissions were increased due to the failure, the cause of the failure, the estimated 

resultant emissions in excess ofthose allowed in Section X.D., and the methods 

utilized to mitigate emissions and restore normal operations. 

C. Compliance with this malfunction notification provision shall not excuse or 

otherwise constitute a defense to any violation of this permit or any law or 

regulation such malfunction may cause. 

V. Right of Entry 

The EPA Regional Administrator, and/or an authorized representative, upon the 

Colusa Generating Station 

Amended PSD Permit 1 

March 19, 2010 

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presentation of credentials, shall be permitted: 

A. to enter the premises where the source is located or where any records are required 

to be kept under the terms and conditions of this PSD Permit; and 

B. during normal business hours, to have access to and to copy any records required 

to be kept under the terms and conditions of this PSD Permit; and 

C. . to inspect any equipment, operation, or method subject to requirements in this 

PSD Permit; and 

D. to sample materials and emissions from the source(s). 

VI. Transfer of Ownership 

In the event of any changes in control or ownership of the facilities to be constructed, this 

PSD Permit shall be binding on all subsequent owners and operators. Permittee shall 

notify the succeeding owner and operator of the existence of this PSD Permit and its 

conditions by letter, a copy of which shall be forwarded to EPA Region 9. 

VII. Severability 

The provisions of this PSD Permit are severable, and, if any provision of the PSD Permit 

is held invalid, the remainder of this PSD Permit shall not be affected. 

VIII. Other Applicable Regulations 

Permittee shall construct and op'erate this project in compliance with this PSD permit and 

all other applicable federal, state, and local air quality regulations. This PSDpermit does 

not release the Permittee from any liability for compliance with other applicable federal, 

state and local environmental laws and regulations, including the Clean Air Act. 

IX. Reserved 

X. Special Conditions 

A. Reserved 

B. Air Pollution Control Equipment and Operation 

1. Prior to initial startup, as defined in Condition X.E. 7, Permittee shall 

install, and thereafter continuously operate and maintain: 

a. Dry Low NOx Burners, Selective Catalytic Reduction (SCR) and 

Oxidation Catalyst units to control NOx and CO emissions from 

EU-l and EU-2; and 

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Amended PSD Permit 1 

March 19, 2010 
b. A low NOx burner for EU-3. 

2. The aforementioned "continuous periods of operation" do not include 

periods of shakedown, startup and shutdown, as defined in Condition X.E. 

except as required by Condition X.B.3. 

3. During any turbine startup, ammonia injection shall be initiated as soon as 

the SCR catalyst temperature exceeds 500 degrees F. 

4. The SCR units for EU-I and EU-2 shall be designed to meet a NOx' 

emission limit of no more than 2.0 ppmvd (I-hr average) corrected to 15 

percent O2, for the life of the SCR catalyst. 

5. Permittee shall ensure that the duct burners are not operated unless the 

associated turbine units are in operation. 

C. Continuous Monitoring Systems 

1. At the earliest feasible, opportunity, in accordance with the 

recommendations of the equipment manufacturer and the construction 

contractor, Permittee shall install, and thereafter operate, maintain, certify, 

and quality-assure a continuous emission monitoring system (CEMS) for 

each CT which measures stack gas NOx , CO and O2 concentrations in 

ppmv. The pollutant concentrations shall be corrected to 15 percent 02 on 

a dry basis. 

2. The NOx and 02 CEMS shall meet the applicable requirements of 40 CFR 

Part 60 Appendix B, Performance Specifications 2 and 3, and 40 CFR Part 

60 Appendix F, Procedure 1. The operator may use the procedures in the 

Linearity Check of 40 CFR Part 75, Appendix A, section 6.2 in lieu ofthe 

cylinder gas audit procedures in 40 CFR Part 60, Appendix F, Procedure 1. 

3. The CO CEMS shall meet the applicable requirements of 40 CFR Part 60 

Appendix B, Performance Specification 4, and 40 CFR Part 60 Appendix 

F, Procedure 1, except the relative accuracy specified in section 13.2 of 40 

CFR Part 6Q Appendix B, Performance Specification 4 shall not exceed 20 

percent. 

4. The performance evaluation of the CEMS may either be conducted 

separately, as specified in 40 CFR 60.4405(b)(5), or as part ofthe initial 

performance test of each emission unit. 

5. The CEMS shall complete a minimum of one cycle of operations 

(sampling, analyzing and data recording) for each successive IS-minute 

period. 

6. Permittee shall submit a CEMS performance test protocol to the EPA no 

later than 30 days prior to the test date to allow review of the test plan and 

to arrange for an observer to be present at the test. The performance test 

shall be conducted in accordance with the submitted protocol, and any 

Colusa Generating Station Page 5 of 13 

Amended PSD Permit 1 

March 19,2010 I 
changes required by EPA. 

7. Permittee shall furnish the EPA a written report of the results of 

performance tests within 60 days of completion. 

8. The stack gas volumetric flow rates shall be calculated in accordance with 

the fuel flow meter requirements of 40 CFR Part 75 Appendix D in 

combination with the appropriate parts of EP A Method 19. 

9. Prior to the date of initial startup (as defined in this PSD permit), 

Permittee shall install, and thereafter maintain and operate, in accordance 

with X.C.1., continuous monitoring and recording systems to measure and 

record the following operational parameters: 

a. The ammonia injection rate of the ammonia injection system. 

b. Exhaust gas temperature at the inlet to the SCR reactor. 

D. Emission and Operational Limits 

The following emission and operational limits shall apply at all times, except as 

provided below: 

1. Total annual emissions from EU-1, EU-2, EU-3, and EU-4 shall not 

exceed the following: 

a. 184.7 tons NOx per rolling 12-month period 

b. 267.9 tons CO per rolling 12-month period 

c. 47.5 tons VOC per rolling 12-month period 

d. 103.4 tons PM per rolling 12-month period 

e. 103.4 tons PMIO per rolling 12-month period 

2. Daily emissions from each CT (EU-l' and EU-2) shall not exceed the 

following: 

a. 1,497.3 lbs NOx per day 

b. 3,829.5 lbs CO per day 

c. 315.3 lbs VOC per day 

d. 324lbs of PM per day 

e. 324lbs ofPMIO per day 

3. Emissions from each CT (EU-1 and EU-2) shall not exceed the following, 

except as provided by the provisions of Condition X.E.: 

a. 19.61bs of NO x per hour or 2.0 ppmvd NOx, corrected to 15 

percent 02, averaged over any I-hour period 

b. 17.91bs of CO per hour or 3.0 ppmvd CO, corrected to 15 percent 

Colusa Generating Station Page 6 of 13 

Amended PSD Permit 1 

March 19, 2010 
02, averaged over any consecutive 3-hciur period 

c. 11.0 lbs ofVOC per hour or 2.0 ppmvd VOC, corrected to 15 

percent O2, averaged over any I-hour period 

d. 13.5 lbs of PM per hour 

e. 13.5 lbs of PM 10 per hour 

4. Emissions from EU-3 shall not exceed the following: 

a. 0.39 lbs of NO x per hour or 30.0 ppmvd NOx, corrected to 3 

percent O2, averaged over any consecutive 3-hour period 

b. 0.79 lbs of CO per hour or 100.0 ppmvd CO, corrected to 3 percent 

O2, averaged over any consecutive 3-hour period 

c. 0.0271bs ofVOC per hour or 7 ppmvd VOC, corrected to 3 

percent O2, averaged over any consecutive 3-hour period 

d. 0.029 lbs of PM per hour 

e. 0.0291bs ofPMlO per hour 

5. Emissions from EU-4 shall not exceed the following: 

a. 0.24 lbs PMlO per hour from EU-4 

E. Requirements during Shakedown, Startup and Shutdown Periods 

The CT emission limits in Section X.D.3. shall not apply during CT shakedown, 

startup and shutdown periods. During shakedown, startup and shutdown periods, 

the following requirements shall apply: 

1. The CEMS shall be in operation during each startup and shutdown period. 

2. No more than one CT shall be in startup mode at any time. 

3. Duration of cold startups shall not exceed 270 minutes, warm startups 

shall not exceed 180 minutes, and hot startups shall not exceed 90 minutes 

per occurrence. 

4. Duration of shutdowns shall not exceed 30 minutes per occurrence. 

Colusa Generating Station Page 7 of 13 

Amended PSD Permit 1 

March 19, 2010 
co 

VOC 

PM/PMlO 

5. While in a startup or shutdown period, exhaust emissions for each CT 

shall not exceed the limits in the following table: 

333.3 779.10 152.0 456.20 249.90 259.90 115.0 115.0 

373.6 1355.6 370.3 790.5 429.6 679.6 483.5 483.5 

27.7 106.7 27.7 47.4 27.7 38.0 23.9 23.9 

0.40 1.01 0.40 0.58 0.40 0.33 0.20 0.20 

12.0 48.8 12.0 30.8 12.0 12.8 6.0 6.0 

6. . The time, date and duration of each startup and shutdown event shall be 

recorded. The records shall include lbs/hour emission calculations based 

on the CEMS data. These records shall be kept for five years following the 

date of such events. 

7. For CTs, "initial startup" shall be defined as the first fire of each unit. 

8. Shakedown shall be defined as the period beginning with initial startup 

and ending no later than initial performance testing, during which the 

Permittee conducts operational and contractual testing and tuning to 

ensure the safe, efficient and reliable operation of the plant. 

9. Startup shall be defined as the.period beginning with ignition and lasting 

until the equipment has reached a continuous operating level and meets 

permit limits specified in Condition X.D.3. Cold startup means a startup 

when the combustion turbine has not been in operation during the 

preceding 72 hours. Hot startup means a startup when the combustion 

turbine has been in operation during the preceding 8 hours. Warm startup 

means a startup that is not a hot or cold startup. 

10. Shutdown shall be defined as the period beginning with the lowering of 

equipment from base load and lasting until fuel flow is completely off and 

combustion has ceased. 

11. Compliance with the PMlPMlO and S02 emission limits that apply during 

startup and shutdown periods may be demonstrated by compliance with 

Condition X.I.1. 

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Amended PSD Permit 1 

March 19, 2010 
12. Compliance with the VOC limits that apply during startup and shutdown 

periods shall be based on compliance with the CO limits during the startup 

and shutdown periods. 

F. Performance Tests 

1. Within 60 days after achieving the maximum production rate the facility 

will operate at, but not later than 180 days after the initial startup of 

equipment, and annually thereafter (within 30 days 'ofthe initial 

performance test anniversary), Permittee shall conduct performance tests 

(as described in 40 CFR 60.8) for NOx, CO, VOC, PM, and PMlO 

emissions from each gas turbine. The annual test shall be performed in 

accordance with the requirements of 40 CFR Part 60, Appendix F, 

Procedure 1, Section 5.1.1. 

2. Permittee shall submit a performance test protocol to EPA no later than 30 

days prior to the test to allow review of the test plan and to arrange for an 

observer to be present at the test. The performance test shall be conducted 

in accordance with the submitted protocol, and any changes required by 

EPA. 

3. Performance tests shall be conducted in accordance with the test methods 

set forth in 40 CFR 60.8 and 40 CFR Part 60, Appendix A, as modified 

below: 

a. EPA Methods 1-4 and 7E ifNOx emissions are measured in ppmv. 

b. EPA Methods 1-4, 7E, and 19 ifNOx emissions are measured on a 

heat input basis. 

c. EPA Methods 1-4 and 10 for CO emissions. 

d. EPA Methods 25A or 25B for VOC emissions. 

e. EPA Methods 1-4 and 5 for PM emissions. 

f. EPA Methods 1-4, 5 and 202 - as modified below, for PMlO 

emISSIOns: 

1. EPA Method 202 test methodology must include the 

following: 

(A) A one-hour nitrogen purge, 

(B) The alternative procedure described in section 8.1 to 

neutralize the sulfuric acid, 

(C) Evaporation of the last 1 ml of the inorganic 

fraction by air drying following evaporation of the 

bulk of the impinger water in a 105°C oven as 

described " in the first sentence of section 5.3.2.3., 

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Amended PSD Permit 1 

March 19,2010 
, 

and 

(D) Each test run period shall be 2 hours. 

11. In lieu of Method 202, the Permittee may use EPA 

Conditional Test Methods for particulate matter: CTM-039 

or CTM-040. 

g. In lieu of the specified test methods, alternative methods may be 

used with prior written approval from EP A. 

4. In addition to the performance test for N02 required in condition X.F.1, 

the initial performance test conducted after 'initial startup' shall use the 

test procedures for a 'high N02 emission site,' as specified in San Diego 

Test Method 100, to measure N02 emissions. The source shall be 

classified as either a 'low' or 'high' N02 emission site based on these test 

results. If the emission source is classified as a: 

a. 'high N02 emission site,' then each subsequent performance test 

shall use the test procedures for a 'high N02 emission site,' as 

specified in San Diego Test Method 100. 

b. 'low N02 emission site,' then the test procedures for a 'high N02 

emission site,' as specified in San Diego Test Method 100, shall be 

performed once every five years to verify the source's 

classification as a 'low N02 emission site.' 

5. The performance test methods specified in Condition X.F.3., may be 

modified as follows: 

a. Perform a minimum of 9 reference method runs, with a minimum 

time per run of 21 minutes, at a single load level, between 90 and 

100 percent of peak (or the highest physically achievable) load. 

b. Use the test data both to demonstrate compliance with the 

applicable NOx emission limit and to provide the required 

reference method data for the RATA of the CEMS. 

6. For performance test purposes, sampling ports, platforms, and access shall 

be provided on the emission unit exhaust system in accordance with the 

requirements of 40 CFR 60.8(e). 

7. Pepnittee shall furnish the EPA a written report ofthe results of 

performance tests within 60 days of completion. 

8. Upon written request from the Permittee, and adequate justification, EPA 

may waive a specific annual test and/or allow for testing to be done at less 

than maximum operating capacity. 

9. ~ The CEMS shall be tested annually and quarterly in accordance with the 

requirements of 40 CFR 60 Appendix F, Procedure 1. 

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Amended PSD Permit 1 

March 19, 2010 
G. Recordkeeping and Reporting 

1. Permittee shall maintain records of the hours of operation for EU -3 and 

EU-4. 

2. Permittee shall maintain records ofthe fuel used in EU-I, EU-2, and 

EU-3. 

3. Permittee shall maintain all records on site of actual operating data and 

emissions calculations for lblhr, lb/event, lb/day and tpy emissions limits 

required in section X.D. ofthis PSD Permit. 

4. Permittee shall maintain CEMS records that contain the following: the 

occurrence and duration of any startup, shutdown or malfunction, 

performance testing, evaluations, calibrations, checks, adjustments, 

maintenance, duration of any periods during which a continuous 

monitoring system or monitoring device is inoperative, and emission 

measurements. 

5. Permittee shall maintain records and submit a written report of all excess 

emissions to EPA semi-annually. The report is due on the 30th day 

following the end of the calendar quarter and shall include the following: 

a. Time intervals, data and magnitude of the excess emissions, the 

nature and cause (if known), corrective actions taken and 

preventive measures adopted; 

b. Applicable time and· date of each period during which the CEMS 

was inoperative (monitor down time), except for zero and span 

checks, and the nature of system repairs or adjustments; arid 

c. A negative declaration when no excess emissions occurred or when 

the CEMS has not been inoperative, repaired, or adjusted. 

6. Excess emissions shall be defined as any operating hour in which the 4-

hour rolling average NOx concentration, or the 3-hour rolling average CO 

concentration, as measured by the CEMS, exceeds the maximum emission 

limits set forth in Condition X.D.3. 

7. A period of monitor down time shall be any unit operating hour in which 

'sufficient data are not obtained to validate the hour for NOx, CO or O2• 

8. Excess emissions indicated by the CEM system shall be considered 

violations of the applicable emission limit for the purpose of this permit. 

9. All records required by this PSD Permit shall be retained for five years 

following the date of such measurements, maintenance, and reports. 

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Amended PSD Permit 1 

March 19, 2010 
H. New Source Performance Standards 

The proposed power plant is subject to the federal regulations entitled Standards 

of Performance for New Stationary Sources (40 CFR Part 60). The owner or 

operator shall meet all applicable requirements of 40 CFR Part 60 Subparts A, Dc, 

andKKKK. 

1. Fuel Use 

1. Permittee shall use only pipeline quality natural gas to fire EU-1, EU-2, 

and EU-3. 

2. Permittee shall keep a monthly record of the quantity of natural gas used in 

EU-1, EU-2, and EU-3. 

3. Permittee shall sample and record the sulfur content of the natural gas fuel 

on a monthly basis. 

4. The monthly fuel sulfur content reading shall not exceed 0.75 grain per 

100 dry standard cubic feet, and the rolling 12-month average fuel sulfur 

content shall not exceed 0.68 grains per 100 dry standard cubic feet. 

5. The fuel sulfur content of the natural gas shall be determined using any of 

tre following test methods: ASTM D1072, D3246, D4468, D5504 or 

D6667. 

XI. Agency Notifications 

A. Unless otherwise directed by the EPA or this permit, the owner or operator shall 

submit a copy of all test plans, reports, certifications, notifications, and other 

information pertaining to compliance with this permit to: 

Director, Air Division (Attn: AIR-5) 

U. S. Environmental Protection Agency Region 9 

75 Hawthorne Street 

San Francisco, CA 94105-3901 

Email: R9.AEO@epa.gov 

Fax: (415) 947-3579 

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Amended PSD Permit 1 

March 19, 2010 

Page 12 of 13 
B. The owner or operator shall submit permit applications, permit amendments, and 

other applicable permit information, which includes but not limited to installation 

of control equipment, replacement of an emissions unit, and changes that 

contravene permit terms, to: 

Director, Air Division (Attn: AIR-3) 

. U. S. Environmental Protection Agency Region 9 

75 Hawthorne Street 

San Francisco, CA 94105-3901 

C. Copies of all correspondence required by this PSD Permit shall be forwarded to:, 

Air Pollution Control Officer 

Colusa County APCD 

100 Sunrise Blvd. #F 

Colusa, CA 95932-3246 

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Amended PSD Permit 1 

March 19, 2010 

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