### PREVENTION OF SIGNIFICANT DETERIORATION PERMIT ISSUED PURSUANT TO THE REQUIREMENTS AT 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 approximately 31-acres within a 100-acre parcel ofagricultural land north ofthe City of Williams, in Colusa County, California (Section 35, Township 18N, Range 4W)
Pursuant to the provisions ofthe Clean Air Act (CAA), SubchapterI, Part C (42 U.s.C. Section 7470, et. seq.), and the Code ofFederal Regulations (CFR) Title 40, Section 52.21, the United States Environmental Protection AgencyRegion 9 (EPA) is issuing aPrevention of Significant Deterioration (PSD) air qualitypermit to the Pacific Gas & Electric Company (PG&E). The Permit applies to the construction and operation ofanew 660 mega-watt (MW) combined cycle powerplant called Colusa Generating Station (CGS), in Colusa County, Califorrtia. PG&E is authorized to construct and operate the CGS powerplant as described herein, in accordance with the permit application (andplans submitted with the permit application), the federal PSD regulations at 40 CFR § 52.21, and otherterms and conditions set forth in this PSD Permit. Failure to comply with any condition orterm set forth in this PSD Permit maybe subject to enforcement actionpursuant to Section 113 ofthe 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 (District) airpollution control rules and regulations. This PSDPermitbecomes effective on the date ofissuance pursuant to 40 CFR § 124.15(b)(3).

# ~~ebOrahJOrdan VDirector, Air Division

# ~zqlo( ae

### 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 ofa 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 ofthe 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 Prevention ofSignificant Deterioration Program for nitrogen oxides (NOx), carbon monoxide (CO), volatile organic compounds (VOC), particulate matter (PM), and particulate matter less than 10 microns (PMlO). 

### EQUIPMENT DESCRIPTION Emission Unit Id. Description EU-l One (1) natural gas-fired CT generatorrated at 172 MW, vented to a HRSG with a 688 MMBtulhr duct burner EU-2 One (1) natural gas-fired CT generatorrated at 172 MW, vented to a HRSG with a 688 MMBtulhr ductburner EU-3 One (1) natur:al gas-fired 40 MMBtulhr auxiliaryboiler EU-4 One (1) 1,340 brake horsepower, diesel-fueled emergency engine to power an electrical generator EU-5 One (1) 300 brake horsepower, diesel-fueled firewater pump engine to powera firewater pump 

### PERMIT CONDITIONS I. Permit Expiration As provided in 40 CFR 52.21(r), this PSD Permit shall become invalid ifconstruction: A. is not commenced (as defined in 40 CFR52.21(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. PermitNotification Requirements Permittee shall notify EPA Region 9 in writing orby electronic**~ail** ofthe: A. date construction is commenced, postmarked within 30 days ofsuch date. B. actual date ofinitial startup, as defined inCondition X.E.7., postmarked within 15 days ofsuch date.

Colusa Generating Station Final PSD Permit September 29, 2008 Page 2 of 13C. date upon which initial performance tests will commence, in accordance with the provisions ofCondition XF.l., postmarked not less than 30 days prior to such date. Notification maybe provided with the submittal ofthe performance test protocol required pursuant to Condition XF.2. D. date upon which initial performance evaluation ofthe CEMS will commence in accordance with 40 CFR 60. 13(c), postmarked not less than 30 days prior to such date. Notification maybe provided with the submittal ofthe CEMS performance test protocol requiredpursuant to Condition X.C.6.
III. Facility Operation At all times, including periods ofstartup, shutdown and malfunction, Permittee shall, to the extentpracticable, maintain and operate the facility including associated airpollution control equipment in a manner consistent with good airpollution control practice for minimizing emissions. Determination ofwhether acceptable operating and maintenance procedures are being used will be based on information available to the EPA which may include, but is not limited.to, monitoring results, opacity observations, review of operating maintenance procedures and inspection ofthe source.
IV. Malfunction Reporting. A. Permittee shall notify EPA by facsimile or electronic mail at R9.AEO@epa.gov withintwo (2) working days following the discovery ofany failure ofairpollution control equipment, process equipment, or ofaprocess to operate in a normal manner, which results in an increase in emissions above the allowable emission limits stated in Section XD. ofthis permit. B. In addition, Permittee shallnotify EPA in writing or electronic mail within fifteen (15) days ofany such failure described under Condition IV.A. The notification shall include a description.'ofthe malfunctioning equipment or abnormal operation, the date ofthe initial malfunction, the period oftime overwhich emissions were increased due to the failure; the cause ofthe 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 notificationprovision shall not excuse or otherwise constitute a defense to any violation ofthis 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 presentation ofcredentials, shall be permitted: A. to enter the premises where the source is located orwhere any records are required to be kept under the terms and conditions ofthis PSD Permit; and

Colusa Generating Station Final PSD Permit September 29, 2008 Page 3 of 13B. during normal business hours, to haveaccess to and to copy any records required to be kept under the terms and conditions ofthis 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 ofOwnership In the event ofany changes in control or ownership ofthe facilities to be constructed, this PSD Permitshall be binding on all subsequent owners and operators. Permittee shall notify the succeeding owner and operator ofthe existence ofthis PSD Permit and its conditions by letter, a copy ofwhich shall be forwarded to EPA Region 9.


### VII. Severability The provisions ofthis PSD Permit are severable, and, ifanyprovision ofthe PSD Permit is held invalid, the remainder ofthis PSD Permit shall notbe affected.


### VIII. Other Applicable Regulations Permittee shall construct and operate this project in compliance with this PSD permit and all other applicable federal, state, and local air qualityregulations. This PSD permit 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.**~eserved** 

### X. Special Conditions A. Reserved
B. 

### Air Pollution Control Equipment and Operation 1. Priorto initial startup, as defined in Condition X.E.7, Permittee shall install, and thereafter continuously operate and maintain:
a. Dry Low NOx combustors, Selective Catalytic Reduction (SCR) and Oxidation Catalyst units to control NOx and CO emissions from EU-l and EU-2; and b. An ultra low NOxburner for EU-3. 2. The aforementioned "continuous periods ofoperation" do not include periods ofshakedown, startup and shutdown, as defined in Condition XE. except as required by Condition X.B.3

.

. Colusa Generating Station Page 4 of 13

Final PSD Permit September 29, 2008

### 3. During anyturbine startup, ammonia injection shall be initiated as soon as the SCR catalyst temperature exceeds 500 degrees F. 4. The SCRunits for EU-l and EU-2 shall be designed to meet a NOx 

### emission limit ofno more than 2.0 ppmvd (I-hr average) corrected to 15 percent O2, 

### for the life ofthe SCR catalyst. 5. Permittee shall ensure that the ductburners 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 ofthe equipmentmanufacturer 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 02 concentrations in ppmv. The pollutant concentrations shall be corrected to 15 percent O2 

### on a drybasis. 2. The NOx 

### and O2 

### CEMS shall meet the applicable requirements of40 CFR Part 60 Appendix B, Performance Specifications 2 and 3, and 40 CFR Part 60 AppendixF, Procedure 1. The operatormay use the procedures in the Linearity Check of40 CFR Part 75, Appendix A, section 6.2 in lieu ofthe cylinder gas auditprocedures in 40 CFR Part 60, Appendix F, Procedure 1. 3. The CO CEMS shall meet the applicable requirements of40 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 of40 CFR Part 60 Appendix B, Performance Specification 4 shall not exceed 20 percent. 4. The performance evaluation ofthe CEMS may eitherbe conducted separately, as specified in 40 CFR 60.4405(b)(5), or as part ofthe initial performance test ofeach emission unit. 5. The CEMS shall complete aminimum ofone cycle ofoperations (sampling, analyzing and datarecording) for each successive IS-minute period. 6. Permittee shall submit a CEMS performance testprotocol to the EPA no laterthan 30 days priorto the test date to allow review ofthe testplan and to arrange for an observerto be present at the test. The performance test shall be conducted in accordance with the submittedprotocol, and any changes requiredby EPA. 7. Permittee shall furnish the EPA awritten report ofthe results of performance tests within 60 days ofcompletion.

Colusa Generating Station Page 5 of 13 Final PSD Permit September29, 20088. The stack gas volumetric flow rates shall be calculated in accordance with the fuel flow meterrequirements of40 CPR Part 75 Appendix D in combination with the appropriate parts ofEPA Method 19. 9. Priorto the date ofinitial startup (as defined in this PSD permit), Permittee shall install, and thereaftermaintain and operate, in accordance with XC. 1., continuous monitoring and recording systems to measure and record the following operational parameters:
a. The ammonia injection rate ofthe ammonia injection system. b. Exhaust gas temperature at the inletto the SCRreactor.


### 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-l, EU-2, EU-3, EU-4 and EU-5 shall not exceed the following:
a. 185.6 tons NOxperrolling 12-monthperiod b. 272.2 tons CO perrolling 12-monthperiod
c. 48.2 tons VOC perrolling 12-monthperiod d. 142.2 tons PM perrolling 12-monthperiod
e. 142.2 tons PMlO perrolling 12-monthperiod 2. Daily emissions from each CT (EU-l and EU-2) shall not exceed the following:
a. 1,497.3 lbs NOxper day b. 3,829.5 lbs CO per day
c. 315.3 lbs VOC per day d. 482.4lbs ofPM per day
e. 482.4lbs ofPMlO per day 3. Emissions from each CT (EU-l and EU-2) shall not exceed the following, except as provided bythe provisions ofCondition XE.:
a. 19.61bs ofNOx perhour or 2.0 ppmvdNOx,**corre~ted** to 15 percent 

### 02, averaged over any I-hourperiod

Colusa Generating Station Final PSD Permit September 29, 2008 b.

c.
d. 17.91bs ofCO perhour or 3.0 ppmvd CO, corrected to 15 percent O2, averaged over any consecutive 3-hourperiod 11.0lbs ofVOC perhour or 2.0 ppmvd VOC, corrected to 15 percent O2, averaged over any I-hourperiod 20 lbs ofPM perhour
Page 6 of 13

### e. 20 lbs ofPMlO 

### perhour 4. Emissions from EU-3 shall not exceed the following:
a. 0.48lbs ofNOx

### perhour or 9.0 ppmvdNOx, 

### correctedto 3 percent O2, 

### averaged over'any consecutive 3-hourperiod b. 1.63 lbs ofCO perJ:toUr or 50.0 ppmvd CO, correctedto 3 percent O2, 

### averaged over any consecutive 3-hourperiod
c. 0.181bs ofVOC perhour or 10.0 ppmvd VOC, corrected to 3 percent O2, 

### averaged over any consecutive 3-hourperiod d. 0.33 lbs ofPM perhour
e. 0.33 lbs ofPMlO 

### perhour 5. Emissions from EU-4 and EU-5 shall not exceed the following:
a. 13.88 lbs NOx

### perhour from EU-4 b. 1.98 lbs NOx

### perhour from EU-5

. 6. EU-3 shall operate no more than 3,744 hours peryear.

7. EU-4 and EU-5 shall each operate no more than 50 hours peryear and no more than 1 hourper day for testing and maintenance purposes.
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 shutdownperiods. During shakedown, startup and shutdown periods, the following requirements shall apply: 1. The CEMS shall be in operation during each startup and shutdownperiod. 2. No more than one CT shall be in startup mode at any time. 3. Duration ofcold 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 ofshutdowns shall not exceed 30 minutes per occurrence.

Colusa Generating Station Page 7 of 13 Final PSD Permit September 29, 20085. While in a startup or shutdownperiod, exhaust emissions for each CT shall not exceed the limits in the following table:



# co VOC

PM/PMlO 

### 333.3 373.6 27.7 0.40 12.0 779.10 1355.6 106.7 1.01 48.8 152.0 370.3 27.7 0.40 12.0 456.20 249.90 259.90 790.5 429.6 679.6 47.4 27.7 38.0 0.58 0.40 0.33 30.8 12.0 12.8 115.0 483.5 23.9 0.20 6.0 115.0 483.5 23.9 0.20 6.0

6. The time, date and duration ofeach startup and shutdown event shall be recorded. The records shall include Ibs/hour emission calculations based on the CEMS data. These records shall be kept for five years following the

. date ofsuch events. 7. For CTs and boilers, "initial startup" shall be defined as the first fire of each unit. 8. Shakedown shall be defined as the periodbeginning withinitial startup and ending no laterthan initial performance testing, during which the Permittee conducts operational and contractual testing .and tuning to ensurethe safe, efficient and reliable operation ofthe plant. 9. Startup shall be defined as the period beginnIng with ignition and lasting until the equipmenthas 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 notbeen in operation during the preceding 

### 72 hours. Hot startup means a startup when the combustion turbine has been in operation during the preceding 8hours. Warm startup means a startup that is not ahot or cold startup. 

### 10. Shutdown shall be defined as the periodbeginning with the lowering of equipment from base load and lasting until fuel flow is completely offand combustion has ceased. 

### 11. Compliance with the PM/PMlO and S02 emission limits that apply during startup and shutdown periods maybe demonstratedby compliance with Condition X.ll.

Colusa Generating Station Page 8 of 13 Final PSD Permit September 29, 200812. Compliance with the VOC limits that apply during startup and shutdown periods shall be based on compliancewith 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 laterthan 180 days after the initial startup of equipment, and annually thereafter (within 30 days ofthe initial performance test anniversary), Permittee shall conductperformance tests (as described in 40 CFR 60.8) for NOx, CO, VOC, PM, and PMlO emissions from each gas turbine and the auxiliaryboiler. The annual test shall be performed in accordance with the requirements of40 CFR Part 60, Appendix F, Procedure 1, Section 5.1.1. 2. Permittee shall submit aperformance test protocol to EPA no laterthan 30 days priorto the test to allow review ofthe test plan and to arrange for an observerto 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 inppmv. b. EPA Methods 1-4, 7E, and 19 ifNOx emissions are measured on a heat inputbasis.
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 PM10 emISSIOns:
1. EPA Method 202 test methodologymust include the following: (A) A one-hour nitrogen purge, (B) The alternative procedure described in section 8.1 to neutralize the sulfuric acid,

Colusa Generating Station Final PSD Permit September 29, 2008 (C) Evaporation ofthe last 1 ml ofthe inorganic fraction by air drying following evaporation ofthe bulk ofthe impinger water in a 105°C oven as described in the first sentence ofsection 5.3.2.3., and
Page 9 of 13(D) Each test run period shall be 2 hours.
11. In lieu ofMethod 202, the Permittee may use EPA Conditional Test Methods for particulate matter: CTM-039 or CTM-040. g. In lieu ofthe specified test methods, alternative methods maybe used withpriorwritten approval from EPA. 4. In addition to the performancetest for N02 required in condition XF.1, the initial**per~ormance** test conducted after 'initial startup' shall use the test procedures for a 'high N02 emission site,' as specified in San Diego TestMethod 100, to measure N02 emissions. The source shall be classified as either a 'low' or 'high' N02 emission site based on these test results. Ifthe emission source is classified as a:
a. 'high N02 emission site,' then each subsequentperformance test shall use the testprocedures for a 'high N02 emission site,' as specified in San Diego TestMethod 100. b. 'low N02emission 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., maybe modified as follows:
a. Perform a minimum of9 reference method runs, with a minimum time perrun of21 minutes, at a single load level, between 90 and 100 percent ofpeak (or the highest physically achievable) load. b. Use the test databoth to demonstrate compliance with the applicable NOx emission limit and to provide the required reference method data for the RATA ofthe CEMS. 6. Forperformance testpurposes, sampling ports, platforms, and access shall be provided on the emission unit exhaust system in accordance with the requirements of40 CFR 60.8(e). 7. Permittee shall furnish the EPA a written report ofthe results of performance tests within 60 days ofcompletion. 8. Upon writtenrequest from the Permittee, and adequatejustification, 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 of40 CFR 60 Appendix F,Procedure 1.

Colusa Generating Station Page 10 of 13 Final PSD Permit September 29, 2008G. Recordkeeping and Reporting 

### '1. Permittee shall maintain recordsofthe hours ofoperation for EU-3, EU-4 and EU-5. 2. Permittee shall maintain records ofthe fuelused·in EU-1, EU-2, EU-3, EU-4 and EU-5. 3. Permittee shall maintain records ofthe sulfur content ofthe diesel fuel used in EU-4 and EU-5. 4. Permittee shall maintain all records on site ofactual operating data and emissions calculations for lblhr, lb/event, lb/day arid tpy emissions limits required in section X.D. ofthis PSD Permit. 5. Permittee shall maintain CEMS records that contain the following: the occurrence and duration ofany startup, shutdown ormalfunction, performance testing, evaluations, calibrations, checks, adjustments, maintenance, duration ofanyperiods during which a continuous monitoring system ormonitoring device is inoperative, and emission measurements. 6. Permittee shall maintain records and submit a written report ofall excess emissions to EPA semi-annually. The report is due on the 30th 

### day following the end ofthe calendar quarter and shall include the following:
a. Time intervals, data and magnitude ofthe excess emissions, the nature and cause (ifknown), corrective actions taken and preventive measures adopted; b. Applicable time and date ofeachperiod during which the CEMS was inoperative (monitor down time), except for zero and span checks, and the nature ofsystem repairs or adjustments; and
c. A negative-declaration when no excess emissions occurred or when the CEMS has notbeen inoperative, repaired, or adjusted. 7. Excess emissions shall be defined as any operating hour in which the 4- hourrolling average NOx 

### concentration, orthe 3-hourrolling average CO concentration, as measured bythe CEMS, exceeds the maximum emission limits set forth in Condition XD.3. 8. 

### A period ofmonitor down time shall be any unit operating hourin which sufficient data are not obtained to validate the hour for NOx, 

### CO or O2• 

### 9. Excess emissions indicatedbythe CEM system shall be considered violations ofthe applicable emission limit for the purpose ofthis permit. 10. All records requiredbythis PSD Permit shall be retained for five years following the date ofsuch measurements, maintenance, and reports.

Colusa Generating Station Page 11 of 13 Final PSD Permit September 29, 2008H. 

### New Source Performance Standards The proposed powerplant is subject to the federal regulations entitled Standards ofPerformance for New Stationary Sources (40 CFR Part 60). The owner or operator shall meet all applicable requirements of40 CFR Part 60 Subparts A, Dc, IIll and KKKK.
1. 

### Fuel Use 1. Natural Gas Usage:
a. Permittee shall use onlypipeline quality natural gas to fire EU-1, EU-2, and EU-3. b. Permittee shall keep a monthlyrecord ofthe quantity ofnatural gas used in EU-1, EU-2, and EU-3.
c. Permittee shall sample and record the sulfur content ofthe natural gas fuel on a monthly basis. d. The monthly fuel sulfur contentreading 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.
e. The fuel sulfur content ofthe natural gas shall be determinedusing any ofthe following test methods: ASTM D1072, D3246, D4468, D5504 or D6667. 2. Diesel Usage:
a. The sulfur content ofdiesel fuel used in EU-4 and EU-5 shall not exceed 15 ppm.



### XI. Agency Notifications A. Unless otherwise directed by the EPA or this permit, the owner or operator shall submit a copy ofall test plans, reports, certifications, notifications, and other information pertaining to compliance with this permit to: Director, AirDivision (Attn: Air-5) EPA Region IX 75 Hawthorne Street San Francisco, CA 94105-3901 Email: R9.AEO@epa.gov Fax: (415) 947-3579

Colusa Generating Station Final PSD Permit September 29, 2008 Page 12 of 13B. The owner or operator shall submitpermit applications, permit amendments, and other applicable permit information, which includes but not limited to installation ofcontrol equipment, replacement ofan 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 C. Copies ofall correspondence requiredby this PSD,Permit shall be forwarded to: Air Pollution Control Officer Colusa County APCD 100 Sunrise Blvd. #F Colusa, CA 95932-3246

Colusa Generating station Final PSD Permit September 29, 2008 Page 13 of 1?