### 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: Onapproxima!ely 31-acres within a 100-acre parcel ofagricultural land north ofthe City of Williams, in Colusa County, California (Section 35, Township 18N, Range 4W)
Pursuantto the provisions ofthe CleanAir Act (CAA), Subchapter I, Part C (42 U.S.C. Section 

### 7470,et. seq.), and theCode ofFederal Regulations (CFR) Title 40, Section 52.21, the United States Environmental ProtectionAgency Region 9 (EPA) is issuing anAmended

### Prevention of SignificantDeterioration (PSD) air quality permitto the Pacific Gas & Electric Company (PG&E). This Amended PSD Permitrevises the PSD permit issued to PG&E on September 29, 2008, for the construction and operation ofa 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 powerplant 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 inthis Amended PSD Permit. Failure to comply with any condition orterm set forth in this Amended PSD Permit will be grounds for enforcement action pursuantto Section 113 ofthe CleanAir Act. This permit does notrelieve CGS from the obligationto comply with applicable federal, state, and Colusa County Air Pollution Control District air pollution control rules and regulations.
This Amended PSD Permitbecomes effective 30 days after the date ofissuance pursuantto 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 combustionturbine generators (CT), each vented to a heatrecovery 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 lowNOx (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, ventedto a HRSGwith 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 bathheater EU-4 One (1) 8,000 gpm wet surface air cooler


### PERMIT CONDITIONS I. Permit Expiration As provided in40 CFR 52.21(r), this PSD Permit shall become invalid ifconstruction: 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 inwriting orby electronic mail ofthe: A. date construction is commenced, postmarked within 30 days ofsuch date. Colusa Generating Station Amended PSD Permit 1 March 19, 2010 Page 2 of 13B. actual date ofinitial startup, as defined in ConditionX.E.7., postmarked within 15 days ofsuch date. C. date upon which initial performance tests will commence, in accordance withthe provisions ofConditionX.F.1., postmarked not less than 30 days priorto such date. Notification may be provided withthe submittal ofthe performance test protocol required pursuantto ConditionX.F.2. D. date upon which initial performance evaluation ofthe CEMS will commence in accordance with40 CFR 60. 13(c), postmarked not less than 30 days priorto such date. Notification may be provided withthe submittal ofthe CEMS performance test protocol requiredpursuantto ConditionX.C.6.


### III.· Facility Operation At all times, inCluding periods ofstartup, 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 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 EPAby facsimile or electronic mail at R9.AEO@epa.gov within two (2) working days following the discovery ofany failure ofair pollution control equipment, process equipment, or ofa process to operate in a normal manner, which results in an increase in emissions above the allowable emission limits stated in SectionX.D. ofthis permit. B. In addition, Permittee shall notify 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 over which emissions were increased due to the failure, the cause ofthe failure, the estimated resultant emissions in excess ofthose allowed in SectionX.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 ofthis permit or any law or regulation suchmalfunction may cause.


### V. Right ofEntry The EPA Regional Administrator, and/or an authorizedrepresentative, upon the
Colusa Generating Station Amended PSD Permit 1 March 19, 2010 Page 3 of 13presentation ofcredentials, shall be permitted: A. to enterthe premises where the source is located orwhere any records are required to be kept under the terms and conditions ofthis 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 ofthis PSD Permit; and C.

.to inspect any equipment, operation, ormethod subject to requirements inthis PSD Permit; and D. to sample materials and emissions from the source(s).


### VI. Transfer ofOwnership Inthe event ofany changes in control or ownership ofthe facilities to be constructed, this PSD Permit shall 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, ifany provision ofthe PSD Permit is held invalid, the remainder ofthis PSD Permit shall not be affected.


### VIII. OtherApplicable 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 PSDpermitdoes notrelease the Permittee from any liability for compliance with other applicable federal, state and local environmental laws and regulations, including the CleanAir 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 LowNOx Burners, Selective Catalytic Reduction (SCR) and Oxidation Catalyst units to control NOx and CO emissions from EU-l and EU-2; and
Colusa Generating Station Page 4 of 13 Amended PSD Permit 1 March 19, 2010b. A lowNOx burner for EU-3. 2. The aforementioned "continuous periods ofoperation" do not include periods ofshakedown, startup and shutdown, as defined in Condition X.E. except as required by ConditionX.B.3. 3. During any turbine startup, ammonia injection shall be initiated as soon as the SCRcatalyst temperature exceeds 500 degrees F. 4. The SCRunits for EU-I and EU-2 shall be designed to meet a NOx' emissionlimit ofno more than 2.0 ppmvd (I-hr average) correctedto 15 percent O2, for the life ofthe SCRcatalyst. 5. Permittee shall ensure that the duct burners are not operated unless the associated turbine units are in operation.

C. Continuous Monitoring Systems 1. Atthe earliest feasible,opportunity, in accordance withthe recommendations ofthe 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 of40 CFR Part 60 Appendix B, Performance Specifications 2 and 3, and 40 CFRPart 60 Appendix F, Procedure 1. The operator mayuse the procedures in the Linearity Check of40 CFRPart 75, Appendix A, section 6.2 inlieu ofthe cylinder gas audit procedures in 40 CFRPart 60, Appendix F, Procedure 1. 3. The CO CEMS shall meetthe applicable requirements of40 CFRPart 60 Appendix B, Performance Specification 4, and 40 CFRPart 60 Appendix F, Procedure 1, exceptthe relative accuracy specified in section 13.2 of40 CFRPart 6Q Appendix B, Performance Specification 4 shall not exceed 20 percent. 4. The performance evaluation ofthe CEMS may eitherbe conducted separately, as specified in40 CFR 60.4405(b)(5), or as part ofthe initial performance test ofeach emissionunit. 5. The CEMS shall complete a minimum ofone cycle ofoperations (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 ofthe test plan and to arrange for an observer to be present atthe 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 ofthe results of performance tests within 60 days ofcompletion. 8. The stack gas volumetric flow rates shall be calculated in accordance with the fuel flow meter requirements of40 CFRPart 75 Appendix D in combination with the appropriate parts ofEPA Method 19. 9. Prior to the date ofinitial startup (as defined inthis 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 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-1, EU-2, EU-3, and EU-4 shall not exceed the following:
a. 184.7 tons NOx

### perrolling 12-monthperiod b. 267.9 tons CO perrolling 12-monthperiod
c. 47.5 tons VOC per rolling 12-monthperiod d. 103.4 tons PM perrolling 12-monthperiod
e. 103.4 tons PMIO perrolling 12-monthperiod 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 ofPMper day
e. 324lbsofPMIO per day 3. Emissions from each CT (EU-1 and EU-2) shall not exceed the following, except as provided by the provisions ofCondition X.E.:
a. 19.61bs ofNOx

### per hour or 2.0 ppmvd NOx, 

### corrected to 15 percent 02, 

### averaged over any I-hourperiod b. 17.91bs ofCO perhour or 3.0 ppmvd CO, corrected to 15 percent Colusa Generating Station Page 6 of 13 Amended PSD Permit 1 March 19, 201002, 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-hourperiod d. 13.5 lbs ofPM perhour
e. 13.5 lbs ofPM10 perhour 4. Emissions from EU-3 shall not exceed the following:
a. 0.39 lbs ofNOxperhour or 30.0 ppmvdNOx, corrected to 3 percent O2, averaged over any consecutive 3-hourperiod b. 0.79 lbs ofCO perhour or 100.0 ppmvd CO, corrected to 3 percent O2, averaged over any consecutive 3-hourperiod
c. 0.0271bs ofVOC perhour or 7 ppmvd VOC, correctedto 3 percent O2, averaged over any consecutive 3-hourperiod d. 0.029 lbs ofPMper hour
e. 0.0291bs ofPMlO perhour 5. Emissions from EU-4 shall not exceed the following:
a. 0.24 lbs PMlO perhour from EU-4



### E. Requirements during Shakedown, Startup and Shutdown Periods The CT emission limits in SectionX.D.3. shall not apply during CT shakedown, startup and shutdown periods. During shakedown, startup and shutdownperiods, 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 Amended PSD Permit 1 March 19, 2010

## co VOC



### PM/PMlO 5. While in a startup or shutdownperiod, exhaust emissions for each CT shall not exceedthe limits inthe 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 ofeach startup and shutdown event shall be recorded. The records shall include lbs/hour emission calculations based onthe CEMS data. These records shall be kept for five years following the date ofsuch events. 7. For CTs, "initial startup" shall be defined as the first fire ofeachunit. 8. Shakedown shall be defined as the periodbeginning 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 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 whenthe 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 offand combustion has ceased. 

### 11. Compliance withthe PMlPMlO and S02 emission limits that apply during startup and shutdownperiods may be demonstrated by compliance with Condition

### X.I.1.

Colusa Generating Station Page 8 of 13 Amended PSD Permit 1 March 19, 201012. 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 maximumproduction 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 conductperformance 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 of40 CFRPart 60, Appendix F, Procedure 1, Section 5.1.1. 2. Permittee shall submit a performance test protocol to EPAno later than 30 days priorto the test to allow review ofthe test plan and to arrange for an observer to be present atthe 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 CFRPart 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 PMlO emISSIOns:
1. EPA Method 202 test methodology mustinclude the following: (A) A one-hour nitrogen purge, (B) The alternative procedure described in section 8.1 to neutralize the sulfuric acid, (C) Evaporation ofthe last 1ml ofthe inorganic fraction by air drying following evaporation ofthe bulk ofthe impinger water in a 105°C oven as 

### " described inthe first sentence ofsection 5.3.2.3.,
Colusa Generating Station Page 9 of 13 Amended PSD Permit 1 March 19,2010

### , and (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 may be used withprior written approval from EPA. 4. In additionto the performance test for N02required in condition X.F.1, the initial performance test conducted after 'initial startup' shall use the test procedures for a 'highN02 emission site,' as specified in SanDiego Test Method 100, to measure N02 emissions. The source shall be classified as either a 'low' or 'high' N02 emission site based onthese test results. Ifthe 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. 'lowN02 emission site,' then the test procedures for a 'high N02 emission site,' as specified in San Diego TestMethod 100, shall be performed once every five years to verify the source's classification as a 'lowN02 emission site.' 5. The performance test methods specified in Condition X.F.3., may be 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 highestphysically 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 ofthe CEMS. 6. Forperformance test purposes, sampling ports, platforms, and access shall be provided onthe emission unit exhaust system in accordance with the requirements of40 CFR 60.8(e). 7. Pepnittee shall furnish the EPA a writtenreport oftheresults of performance tests within 60 days ofcompletion. 8. Upon written request 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 1 0 of 13 Amended PSD Permit 1 March 19, 2010G. Recordkeeping and Reporting 1. Permittee shall maintainrecords ofthe hours ofoperation for EU-3 and EU-4. 2. Permittee shall maintainrecords ofthe fuel used in EU-I, EU-2, and EU-3. 3. Permittee shall maintain all records on site ofactual operating data and emissions calculations for lblhr, lb/event, lb/day and tpy emissions limits required in sectionX.D. ofthis PSD Permit. 4. Permittee shall maintain CEMS records that containthe following: the occurrence and duration ofany startup, shutdown or malfunction, performance testing, evaluations, calibrations, checks, adjustments, maintenance, duration ofany periods during which a continuous monitoring system ormonitoring device is inoperative, and emission measurements. 5. Permittee shall maintainrecords and submit a writtenreport ofall excess emissions to EPA semi-annually. The report is due onthe 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 whichthe CEMS was inoperative (monitor down time), except for zero and span checks, and the nature ofsystem repairs or adjustments; arid
c. A negative declaration when no excess emissions occurred or when the CEMS has notbeen inoperative, repaired, or adjusted. 6. Excess emissions shall be defined as any operating hour in whichthe 4- hourrolling average NOx concentration, orthe 3-hourrolling average CO concentration, as measured by the CEMS, exceeds the maximum emission limits set forth in ConditionX.D.3. 7. A period ofmonitor down time shall be any unit operatinghour 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 ofthe applicable emission limit for the purpose ofthis permit. 9. All records required bythis PSD Permit shall be retained for five years following the date ofsuch measurements, maintenance, and reports.

Colusa Generating Station Page 11 of 13 Amended PSD Permit 1 March 19, 2010H. New Source Performance Standards The proposed powerplant is subject to the federal regulations entitled Standards ofPerformance for New Stationary Sources (40 CFRPart 60). The owner or operator shall meet all applicable requirements of40 CFRPart 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 ofthe quantity ofnatural gas used in EU-1, EU-2, and EU-3. 3. Permittee shall sample and record the sulfur content ofthe natural gas fuel on a monthly basis. 4. 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. 5. The fuel sulfur content ofthe 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 orthis 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, 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

Colusa Generating Station Amended PSD Permit 1 March 19, 2010 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 permitterms, to: Director, Air Division (Attn: AIR-3)

. U. S. Environmental Protection Agency Region 9

75 Hawthorne Street San Francisco, CA 94105-3901
C. Copies ofall 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

Colusa Generating Station Amended PSD Permit 1 March 19, 2010 Page 13 of 13