### United States Environmental Protection Agency

Region 9 Technical Support Document

Navajo Generating Station Salt River Project Agricultural Improvement and Power District Navajo Nation Indian Reservation Coconino County, Arizona

Refined Coal Treatment System February 2016
Tribal Minor NSR Permit: T

- 0004

- NN (See also, PSD Permit No. AZ 08

- 01A)

In accordance with the requirements of the Tribal Minor New Source Review (NSR) Permit Program (see 40 CFR Part 49 )

, EPA is proposing to approve a Federal permit to construct under authority of the
Clean Air Act (CAA) for a Refined Coal Treatment System (RCTS) at the Navajo Generating Station (NGS)

. T his T echnical S upport D ocument (TSD) describ es the equipment that is authorized to be installed and the additional per mit conditions that will be added to the existing PSD permit as a result
of this m inor NSR permit action

.

The final section of the TSD provides information for submitting comments on the proposed minor NSR permit to authorize construction and operation of the RCTS.2

Table of Contents

I. Facility Description 3

II. Refined Coal Treatment System Project Description 3

III. Existing Permits and Regulations Applicable to NGS 7

IV. Permitting Requirements under the Tribal NSR Rule 9

V. Summary of Emissions Increases 10

VI. Air Quality Impact Analysis 13

VII. Control Technology Review 15

VIII. Listed Species

- related Requirements 18

IX. Historic Properties

- related Requirements 19

X. Environmental Justice 19

XI. Authority 21

XII. Public Participation 213

I. Facility Description NGS is a participant owned coal

- fired generating station managed by Salt River Project Agricultural Improvement and Power District (SRP). The co

- owners of NGS are the U.S. Bureau of Reclamation (24.3% ownership), Los Angeles Department of Water and Power (21.2%), SRP (21.7%), Arizona Public

Service Co. (14.0%), N V Energy (11.3%)

, and Tucson Electric Power Co. (7.5%). Los Angeles Department
of Water and Power and N V Ener gy anticipate selling their ownership shares of the plant in the near
future. NGS is loca ted on the Navajo Nation about 5 miles east of Page, Arizona in Coconino County

. Coconino County is currently classified as attainment o r unclassifiable for all Nation al Ambient Air Quality Standards (NAAQS) pollutants ( see 40 CFR 81.303)

.

Facility Location:

Sec 2 T40N R9E
Latitude: 36.903135 N Longitude:

- 111.390242 W Coconino County, Arizona

NGS currently consists of three 750 megawatt (MW) coal

- fired electric steam

- generating units (EGUs), designated as Units 1, 2 and 3, with a total capacity of approximately 2,250 MW, and other ancillary equipment such as coal storage and transferring, coal pulverizing, lime handling operations, and dry ash handling operations. As discussed in detail below, t h is current minor NSR permit action proposes

to authorize installation of additional equipment called the R efined Coal Treatment S ystem (RCTS)

.

II. Refined Coal Treatment System Project Description On February 20, 2015, EPA received an application from SRP for a minor NSR permit allowing construction and operation of the R CTS within the plant boundaries on pre

- disturbed land at NGS. The permit would authorize SRP to construct and operate the RCTS, including ancillary equipment, in order to treat coal with cement kiln dust and calcium bromide for the further reduction of oxides of nitrogen (NO x ) and mercury emissions, respectively , and thus, to take advantage o f a federal tax credit

. SRP has an existing coal conveyor belt system that transfers untreated coal from railcar unloading piles to the pulverizers for crushing . The crushed coal is then fed into one of three existing boilers (Units 1, 2 or 3)
for combusti on to generate steam and produce electricity. SRP is proposing to construct the R CTS to add calcium bromide and cement kiln dust (CKD) to the coal prior to being pulverized and combusted.
Th e R CTS will consist of two new coal feed belt conveyors that will divert coal from the existing conveyor system to two new mixing pugmills where the coal will be mixed with the additives (calcium
bromide and CKD ) . The treated coal will then be fed back from the pugmills into the existing conveyor
system on two new return belt conveyors

. The CKD will be delivered by truck and stored in three new 150 ton silos and two new 20 ton day bins . The calcium bromide will also be delivered by truck and will
be stored in a n ew 8,700 gallon storage tank and two new 405 gallon day tan ks.

Emissions controls will be installed on the new equipment for the RCTS. The transfer points at the new and existing belt conveyors associated with the RCTS will be controlled by two high efficiency dust
collectors. The CKD silos and day bins w ill be c ontrolled by baghouses inherent to each storage device. The baghouses are inherent to the silos and day bins because they help recover CKD and keep the containers under negative pressure , preventing losses of CKD to the atmosphere through any potential
leaks . The baghouses would be present on the silos and day bins solely for material recovery even if
there were no need to install air pollution controls. There are no control devices associated with4

calcium bromide storage or application because it is not volatile will be stored and applied to the coal as a liquid.

The RCTS will result in emissions increases in PM, PM 10 , and PM 2.5

. The emissions increases are primarily from increased truck delivery traffic on existing unpaved roads at NGS, and to a lesser extent
from the new dust collectors to be installed on the belt conveyors and new baghouses associated with

CKD storage silos and day bins

. There will be no emission increases associated with the storage and
transfer of calcium bromide. In addition, there will be minimal increases in emissions of PM, PM 10 , and

PM 2.5 from Units 1, 2, and 3 due to the increased ash content of the coal following the a pplicatio n of

CKD (See Section V below for a summary of the emissions increases). However, the increase in emissions from Units 1, 2, and 3 will not result in changing the permitted emissions limits for the EGUs.

The construction and operation of the R CTS will be within the existing footprint of NGS and the increase in emissions from the changes will not exceed the PSD significance thresholds. Therefore, the

RCTS do es not trigger PSD . T he increase s in PM and PM 10 emissions from the proposed R CTS , however,
are abov e the Tribal NSR minor source thresholds for attainment areas

. Increases in PM 2.5 emissions
are below Tribal NSR minor source thresholds. As described below, the RCTS qualifies as a m inor NSR project , pursuant to 40 CFR 49.153(a)(1).

Figure 1

– Process Flow Diagram of Refind Coal Treatment System5

A. New Coal Feed Belt Conveyors

As discussed above, t wo new coal feed belt conveyors will be installed to deliver the coal to the R CTS and p articulate matter emissions will be controlled from the coal feed belt conveyors by two dust collectors. The maximum flowrate through the dust collector controlling the main transfer points of
coal (see DC

- 12 in the schematic above) will be 16,500 standard cubic feet per minute ( s cfm). The maximum flow rate through the dust collector controlling the particulate emissions from the RCTS building itself (see DC

- 13 in the schematic above) will be 6,000 s cfm. Emissions from the dust collectors
are based on a man ufacturer’s guaranteed emission factor of 0.01 gr/ s cf for standard filters. SRP is installing high

- efficiency filters which guarantee an emission factor of 0.003 gr/ s cf. However, EPA is calculating the potential to emit for this project based on the use of standard dust collection filters. The coal and CKD collected by the dust collectors will be recovered and returned into the RCTS. The dust collectors are being installed primarily to recover product, but have a secondary benefit of providing air pollution control. Therefore, the dust collectors are considered inherent to the process
and are taken into account in calculation of the potential emissions.

B. Calcium Bromide Application

The calcium bromide application system will consist of an 8,700 gallon storage tank, and two 405 gallon day tanks. Liquid calcium bromide will be delivered by truck to the 8,700 gallon storage tank, and then transferred as needed to the day tanks via trans fer pumps. From the day tanks, calcium bromide will be applied to the coal directly and then the treated coal will be fed to the pulverizer prior
to combustion in the boilers. The R CTS Project will consume approximately 45 gallons of calcium bromide per ho ur.

Calcium bromide is a non

- volatile liquid and no air emissions are expected from the storage tanks or during the application to coal. However, the application of calcium bromide can help to oxidize elemental mercury in coal, which makes it easier to re move from parti culate matter control devices.
The RCTS P roject will add calcium bromide to the coal in order to further reduce mercury emissions
from Units 1, 2, and 3. The Mercury Control System discussed in Section III.B was constructed in order
for NGS for comply with the Mercury and Air Toxics Standards ( MATS ) Rule

. The RCTS P roject i s not necessary for compliance with the MATS rule . Rather, it is being constructed to take advantage of a federal tax credit which incentivizes production of refined coal for the reduction of mercury emissions.

C. Cement Kiln Dust Application

Cement Kiln Dust (CKD) is a byproduct of the cement industry which consists mostly of calcium carbonate (lime) and silicon dioxide. Application of CKD to coal prior to combustion can have the benefit of reducing emissions of NO x from th e combustion process. The RCTS P roject will add CKD to
the coal to further reduce NO x emissions from Units 1, 2, and 3. The CKD application of the RCTS is also being constructed to take advantage of a federal tax credit which incentivizes production of refined
coal for the reduction of NO x emissions.

The CKD application system will consist of three 150 ton storage silos and two 20 ton day bins, each equipped with baghouse s . The maximum flowrate through the baghouses connected to each of the6

three 150 ton storage silos is 450 s cfm. The maximum flowrate through each baghouse connected to the two day bins is 1,200 s cfm.

CKD will be truck delivered into the main storage silos for bulk storage. From the storage silos, the CKD will be fed into the day bins and then through one of two screw conveyor s to be mixed with the coal
and calcium bromide in one of two pugmill s . The mixture is then fed back into the existing conveyor
system via two new return belts . The R CTS system will consume approximately 4 tons per hour of CKD.

Particula te matter emissions from the CKD application process are generated from the unloading of CKD into the storage silos and transfer of the CKD into the day bins. Baghouses to capture and control these particulate emissions are integral to the storage silos an d day bins and thus will be operated at all times. Emissions from the storage silo and day bin baghouses are based on manufacturer guaranteed emission factors 0.00025 gr/scf and 0.002 gr/scf, respectively. The baghouses are added to the silos and day bins primarily to recover CKD and have the secondary benefit of providing air pollution control. Therefore, the baghouses are considered integral to the process and are taken into consideration in calculating potential emissions.

D. Additional Truck Traffic

T he delivery of calcium bromide and CKD to NGS will cause an increase in fugitive particulate matter
emissions from increased truck traffic. Emission calculations are based on AP

- 42 Section 13.2.2
information. The a pplicant included an assumed 75 percent co ntrol efficiency for road watering.
However, given the difficu lty in practice of achieving 75 percent control efficiency, we believe that a 50
percent control efficiency is more representative of dust control using water sprays on road. Thus, we used a 50 percent control efficiency in our potential to emit calculations. As discussed in the Control Technology Review Section below, we are adding permit conditions which will be sufficient to ensure 50 percent control efficiency of fugitive dust emissions from roadways.

The minor NSR permit will limit truck traffic for CKD deliveries to a maximum of 720 vehicle miles traveled (VMT) per year and a maximum of 70 VMT per year for calcium bromide deliveries. Calcium
bromide deliveries for the existing Mercury Cont rol System to NGS are 365 VMT per year. The
additional 70 VMT for calcium bromide deliveries for the R CTS Project bring the total to 465 VMT per

year.

E. Emission Increases from Existing Units 1, 2, and 3

The addition of CKD to the coal prior to combustion in existing U nits 1, 2, and 3 will result in increased
emissions of PM, PM 10 , and PM 2.5 due to the increased ash content in the coal. Emission calculations of
these emission increases are based on emission factors from AP

- 4 2 Section 1.1. The evaluation of emission increases were based on an actual to projected actual emissions test allowed for determining applicability of PSD and m inor NSR consistent with requirements under NSR Reform. Coal feed rates
used in the emission ca lculation were based on hourly averages for the 24

- month time period between January 1, 2012 and Decemb er 31, 2013. It is not expected that the coal feed/combustion rates will change following construction of the RCTS project. Although the RCTS P roject is expected to increase projected actual emissions of PM, PM 10 , and PM 2.5 from U nits 1, 2, and 3, the emissions increase is not major under the PSD program . T here will be no change in any emission limits for any of the affected7

units as the facility can accommodate the actual emissions change within their current emissions limit

, and SRP will be required to comply with all existing emission limits in both the PSD and t itle V p ermits
for Units 1, 2 and 3

.

III. Existing Permits and Regulations Applicable to NGS

A. Existing PSD Permit

Currently, NGS has a PSD permit that was issued in late 2008 to allow installation of its Low NO x Burner Project. The PSD permit authorized NGS to install Low NO x Burners at each of its combustion boilers, Units 1, 2 and 3, in 2009

– 2011. Installation of the Low NO x Burner technology resulted in a substantial
decrease in NO x emissions and an increase in emissions of CO that exceeded the PSD significance
thresholds . The PSD permit established federally enforceable emissions limitations for NO x and CO from Units 1, 2 and 3. The emissions limit for NO x in the PSD permit is 0.24 lb/MMBtu on a 30

- day rolling average and CO emissions must remain below 0.23 lb/MMBtu on a 30

- day rolling average, and 0.15 lb/MMBtu based on a 12

- month rolling average.

It is Region 9’s practice to include the requirements from the PSD and Tribal Minor NSR program in a single permit document. As such, we are revising NGS’s existing PSD permit, No. AZ 08

- 01A, to add the

T ribal Minor NSR requirements of this action . This means that if we finalize our proposed authorization
for NGS’ RCTS Project we will revise the PSD permit to include the new equipment and add conditions to the perm it associated with the addition of such equipment

. N GS’s Tribal Minor NSR permit number

is T

- 0004

- NN and that number will be added to PSD permit No . AZ 08

- 01A . All existing conditions in PSD permit No. AZ 08

- 01A remain unchanged by this action. The equipment being added at NGS pursuant to this minor NSR permit action will have no effect o n the existing emission limits for any pollutant s from Units 1, 2, and 3 , including those limits and requirements established by the PSD permit and the Federal Implementation Plans described below

.

B. August 2015 Administrative Amendment

– Mercury Control System

On August 26, 2015, EPA approved an administrative amendment to PSD Permit No. AZ 08

- 01A called the “Mercury Control System” . The administrative amendment authorized construction of a calcium
bromide application system and a powder ed activated carbon system within the existing facility footprint to reduce mercury emissions from Units 1, 2, and 3. The Mercury Control System was
installed at NGS to ensure compliance with the emissions standards in the Me rcury and Air Toxics Standards (MATS) rule

. The project resulted in very small emission increases of particulate matter (PM,

PM 10 , and PM 2.5 ) from the powder ed activated carbon system’s storage silos and fugitive emissions
due to increased VMT for truck tr affic for deliveries of calcium bromide and powder ed activated
carbon. Emission increases due to the Mercury Control System were below the minor NSR thresholds

in 40 CFR 49.153(a) ( 1)(ii)(A) and Table 1 . Therefore, the change to the existing PSD permit was an administrative amendment, pursuant to 40 CFR 49.159(f).

Although the RCTS Project and the Mercury Control System projects are separate because they have different purposes, we have also evaluated the emissions increases together to determine if they would trigger any additional control requirements (e.g. PSD) if the two projects had been aggregated.

T he combination of increased emissions from the Mercury Control System approved under the August8

2015 administrative amendment and t he proposed R CTS Project will not exceed the PSD thresholds for any pollutant. As described below, only the Tribal NSR minor source thresholds for PM and PM 10 are exceeded by the increases due to the RCTS P roject, and no additional minor NSR or PSD thresho lds would have been exceeded had the two projects been combined into one permitting action. Furthermore, the combination of increased emissions of PM 2.5 from the Mercury Control System and
the RCTS Project do not exceed the Tribal NSR minor source threshol d. However, when considering

m inor NSR and PSD applicability of future modifications at NGS, the increases in emissions for all pollutants from these two projects will be taken into account.

C. Federal Implementation Plans Promulgated Regulating NGS

NGS is currently subject to two Federal Implementation Plans regulating emissions from it s operations. In 2010, EPA finalized a FIP e stablish ing emissions limits for sulfur oxides (SO x ) an d particulate matter. The FIP requires SO x emissions to remain below 1.0 l b/MMBtu averaged over a 3

- hour period plant

wide and particulate matter emissions were limited to 0.060 lb/MMBtu on a plantwide basis. This FIP also required dust suppression on the coal handling and storage operations and established a 20% opacity limitat ion on Units 1, 2 and 3, excluding condensed uncombined water droplets. See 40 CFR 49.5513(d).

In 2014, EPA finalized a FIP that included regulations requiring reductions in NO x emissions as a “better

- than

- BART” alternative under the Regional Haze Rule to improve visibility in surr ounding
federal Class I areas. 79 Fed. Reg. 46,514 (Aug 8, 2014 , codified at 40 CFR 49.5513(j) ). The FIP contains regulations resulting in an 84% reduction in NO x emissions when fully implemented

.

D. Title V Operating Permit

EPA issued the first t itle V Operating permit to NGS on June 5, 2001. After Navajo Nation and SRP entered into a Voluntary Compliance Agreement on May 18, 2005 and EPA determined that it was appropriate to treat the Navajo Nation as a state, EPA delegated its t itle V Part 71 operating permit program to the Navajo Nation Environmental Protection Agency (NNEPA)

. See 69 FR 67578 and 71 FR

16773

. When the Part 71 de legation was final on March 21, 2006 , the NNEPA took over administration
of the t itle V permit for NGS. NNEPA has issued one renewal of the t itle V operating permit on July 3,

2008. NN EPA provided notice of a draft t itle V Permit renewal for NGS in Septem ber 2015. NNEPA will incorporate the requirements of this minor NSR permit , if finalized, into the t itle V permit as an administrative amendment pursuant to 40 CFR 71 .7(d)(1)(v).

E. Acid Rain Permit

– 40 CFR Parts 72

- 77

EPA issued the first Phase II Acid Rain Permit under 40 CFR Part 72 on November 14, 1997. Units 1, 2, and 3 at NGS are listed under Part 72, and are therefore subject to the Acid Rain Program , which places
limits for each emission unit on emissions of NO x and SO x . EPA typically issues Acid Rain Permits with
each t itle V p ermit renewal. NNEPA provided public notice of the draft Acid Rain Permit renewal in September 2015.9

IV. Tribal NSR Rule Permitting Requirements

The Tribal NSR Rule requires projects such as the RCTS at major stationary sources that cause a projected emissions increase above m inor NSR thresholds to obtain a permit prior to commencing construction of the proposed project . See 40 CFR 49.153(a)( 1 ). Based on the information submitted in SRP’s application th e RCTS P roject qualifies for a minor NSR permit because the emission increases for
PM and PM 10 shown in Table 1 below are above the minor NSR thresholds and below EPA’s PSD significance thresholds , as also shown in Table 1 below

.

As discussed above, EPA is proposing to add new permit operating conditions to t he existing PSD permit, pursuant to 40 CFR 49.151

- 161 . The new permit conditions will limit the VMT travelled on existing unpaved roads for truck traffic associated with deliveries of CKD and calcium bromide to NGS.
The limit on the number of VMT for truck traffic associated with calcium bromide deliveries has been updated to include the c ombination of existing deliveries and new deliveries to the RCTS . The limits on

VMT for all truck deliveries of CKD and calcium bromide will be on a rolling 12

- month basis. The permit will also contain other operational standards and associated monitoring and recordkeeping necessary to mitigate fugitive dust emissions from roadways, including requirements for watering and limiting the speed of truck delivery traffic.

New monitoring and recordkeeping requirements will also be added to the existing PSD permi t for NGS pursuant to 40 CFR 49.151

- 161. SRP will be responsible for monitoring and recording the occurrence of each delivery of CKD and calcium bromide, the number of VMT associated with each delivery, and the
total number of deliveries and VMT on a rolli ng 12

- month basis. SRP will also be responsible for monitoring visible emissions from the dust collectors and baghouses which will be constructed as part of the RCTS Project. A weekly visible emissions survey is required to be conducted by a person trained
in EPA Method 22

– Visual Determination of Fugitive Emissions from Material Sources and Smoke Emissions from Flares . If visible emissions are detected at any point during these surveys, SRP must
take corrective action within 24 hours to ensure that no vis ible emissions are detectable. SRP will be responsible for properly operating and maintaining the baghouses and dust collectors, as well as keeping spare bags and filters on site for immediate replacement in the event of failure.

For more information on E PA’s determination of new permit conditions, see the Control Technology
Review Section below. In addition, we are also add ing the email address for Region’s 9 Air & TRI
Enforcement Section to Section XI (Agency Notifications) of the permit. We consider th e RCTS to
constitute issuance of a minor NSR permit pursuant to 40 CFR 49.153(a)(1).10

V. Summary of Emission Increases

Table 1 below summarizes the emission increases from this project and provides the applicable permitting thresholds for minor NSR and PSD . NGS is located in an area that is attainment or unclassifiable for all of the National Ambient Air Quality Standards. Therefore, this table reflects the permitting thresholds applicable in attainment areas. Table 1 demonstrates that the R CTS i s above the minor NSR permitting thresholds and below the PSD t hresholds.

Table 1 Refined Coal Treatment System Project Projected Emissions Increase Projected

Emissions

Increase (TPY) Minor NSR

Thresholds (TPY) PSD Thresholds

(TPY)

CO 0 10 100

NOx 0 10 40

SO2 0 10 40

VOC 0 5 40

PM 14.96 10 25

PM10 10.15 5 15

PM2.5 0.75 3 10

Lead 0 0.1 0.6

Fluorides 0 1 3

Sulfuric acid mist 0 2 7 Hydrogen sulfide 0 2 10

Total reduced sulfur 0 2 10 Reduced sulfur compounds 0 2 10

CO2e 0 NA 75,00011

Table 2 shows the potential to emit for each new emissions unit and increases in the projected increases in actual emissions for each existing emissions unit for the R CTS Project.

Table 2 Potential to Emit for Each New Emissions Unit and Projected Increases in Actual Emissions for

Existing Emission Units

– Refined Coal Treatment System

New Emission Unit s – Potential to Emit PM 2.5 (TPY) PM 10 (TPY) PM (TPY)

DC

- 12: Coal Handling Dust Collection System, 16,500 s cfm 0.33 6.19 6.19

DC

- 13: Coal Handling Dust Collection System, 6,000 s cfm 0.12 2.25 2.25

DC

- 14 : Cement Kiln Dust Silo 1, 450 s cfm < 0.01 < 0.01 < 0.01

DC

- 15 : Cement Kiln Dust Silo 2, 450 s cfm < 0.01 < 0.01 < 0.01

DC

- 16 : Cement Kiln Dust Silo 3, 450 s cfm < 0.01 < 0.01 < 0.01

DC

- 17: Cem ent Kiln Dust Day Bin 1, 1,200 s cfm < 0.01 0.09 0.09

DC

- 18: Cem ent Kiln Dust Day Bin 2, 1,200 s cfm < 0.01 0.09 0.09

TR

- 01: Truck Traffic on Existing Unpaved Roads for Cement Kiln Dust Delivery 0.05 0.53 2.05

TR

- 02: Truck Traffic on Existing Unpaved Roads for Calcium Bromide Delivery < 0.01 0. 04 0.14 Existing Emission Units

– Projected Increases
in Actual Emissions 1

U

- 1: Boiler 1 0.08 0.32 1.39

U

- 2: Boiler 2 0.08 0.31 1.33

U

- 3: Boiler 3 0.09 0.33 1.43
Totals 0.75 10.15 14.96

1

– SRP used an actual

- to

- projected

- actual applicability test to determine emission increases from existing Units 1, 2, and 3 for the purposes of m inor NSR and PSD applicability. An actual

- to

- projected

- actual test is allowed to determine NSR applicability f or existing units pursuant to 40 CFR 52.21(a)(2)(iv)(c) . New units which are proposed for construction as part of the RCTS Project are required to use potential to e mit for m inor NSR and PSD applicability purposes.12

Table 3 demonstrates that the Mercury Control System added under an administrative amendment in August 2015 is below both the minor NSR and PSD major permitting thresholds. Table 4 shows the potential to emit for each new emissions unit. (See also, Region 9 Emission Calcula tions Spreadsheet )

Table 3 Mercury Control System Project Potential to Emit

Projected

Emissions

Increase (TPY) Minor NSR

Thresholds (TPY) PSD Thresholds

(TPY)

CO 0 10 100

NOx 0 10 40

SO2 0 10 40

VOC 0 5 40

PM 1.71 10 25

PM10 1.11 5 15

PM2.5 0.9 2 3 10

Lead 0 0.1 0.6

Fluorides 0 1 3

Sulfuric acid mist 0 2 7 Hydrogen sulfide 0 2 10
Total reduced sulfur 0 2 10 Reduced sulfur compounds 0 2 10

CO2e 0 NA 75,000

Table 4 Potential to Emit for Each New Emissions Unit

– Mercury Control System

Emission Unit PM 2.5 (TPY) PM 10 (TPY) PM (TPY)
Truck Traffic PAC Deliveries on Existing Unpaved Roads < 0.01 0.02 0.08
Truck Traffic Calcium Bromide
Deliveries on Existing Unpaved Roads 0.0 2 0.19 0.72 PAC Storage Silo A 0.45 0.45 0.45

PAC Storage Silo B 0.45 0.45 0.45
Totals 0.9 2 1.11 1.7113

Table 5 demonstrates that the combination of the Refined Coal Treatment System added under this minor NSR permit and the Mercury Control System added under an administrative amendment in August 2015 are together above the m inor NSR t hresholds and below the PSD t hresholds.

Table 5 Emissions Increases for Refined Coal Treatment and Mercury Control Systems Combined
Combined Projected

Emissions

Increase (TPY) Minor NSR

Thresholds (TPY) PSD Thresholds

(TPY)

CO 0 10 100

NOx 0 10 40

SO2 0 10 40

VOC 0 5 40

PM 16.67 10 25

PM10 11.26 5 15

PM2.5 1. 67 3 10

Lead 0 0.1 0.6

Fluorides 0 1 3

Sulfuric acid mist 0 2 7 Hydrogen sulfide 0 2 10
Total reduced sulfur 0 2 10 Reduced sulfur compounds 0 2 10

CO2e 0 NA 75,000

VI. Air Quality Impact Analysis

The Tribal Minor NSR regulations at 40 CFR 49.154(d) require that an Air Quality Impact Assessment (AQIA) modeling analysis be performed if there is reason to ensure that new construction will not cause or contribute to a NAAQS or PSD increment violation. Modeling must be performed consistent with procedures outlined in 40 CFR Part 51, Appendix W. If an AQIA reveals that the proposed construction could cause or contribute to a NAAQS or PSD increment violation, such impacts must be addressed before a pre

- con struction permit can be issued.

The proposed RCTS Project at NGS will result in increased emissions of PM, PM 10 , and PM 2.5 . Although all emission increases due to the proposed project are below PSD thresholds, increases in PM and PM 10 exceed minor NSR per mitting thresholds

. An AQIA for PM is not required because there is no longer a NAAQS for P M. A primary and secondary NAAQ S exists for PM 10 , therefore , impacts due to PM 10 are being analyzed to ensure that they do not contribute or cause any impacts on the annual and 24

- hour

PM 10 NAAQS or a PSD increment violation.

SRP conducted a PM 10 and PM 2.5 modeling analysis for the RCTS Project to determine the impact of

emissions increases o n the annual and 24

- hour PM 10 and PM 2.5 NAAQS

. The m odeling protocol outlined in 40 CFR Part 51, Appendix W entails two major steps: a Significant Impact Analysis and a Full Impact14

Analysis. A Significant Impact Analysis considers the emissions associated with the proposed project to determine the air quality impacts on the surrounding area by comparing the modeled impacts using

met eorological data from the past five years to the est ablished Significant Impact Levels (SILs) (see table 6). SILs indicate the level at which emissions of a pollutant are likely to impact the NAAQS. If the modeled impacts from the proposed project are found to exceed the SILs, a Full Impact Analysis (includ ing impacts on both the NAAQS and PSD increments) must be performed.

Table 6 Significant Impact Analysis Results for RCTS Project

Pollutant Averaging Period Maximum Modeled
Ground

- level

Concentration 2 (μg/m 3 ) SILs (μg/m 3 )

PM 10 Annual 0. 60 1

24

- hour 4.24 5

PM 2.5 Annual 0. 04 0.3

24

- hour 0. 23 1.2

2

– The modeling protocol in 40 CFR Part 51 , Appendix W allows the use of five years of off

- site meteorological data or at least one year of on

- site data. For this modeling analysis, five years of surface data from the nearby Page Municipal Airport and upper air data from Flagstaff, AZ were processed to generate meteorological data which could be used in the model. The highest five

- year modeled value was used as the maximum modeled ground

- level concentration at the NGS facility
fence line

.

The AQIA submitted by SRP showed that maximum concentrations of PM 10 and PM 2.5 occur within the existing facility boundary and that increases of these pollutants due to the RCTS Project do not exceed the Significant Impact Levels (SILs) outside the facility boundary and do not result in ambient
concentrations that exceed the NAAQS. S RP submitted a modeling report for PM 2.5 to demonstrate
that PM 2.5 emissions from the RCTS Project are not expected to exceed the minor NSR threshold. Due
to the fact that the PM 2.5 SILs were vacated in 2013, EPA guidance in the memorandum, “Guidance for

P M 2.5 Permit Modeling”, dated May 20, 2014, suggests that an alternative test can be conducted to determine if a Full Impact Analysis is required for PM 2.5 . If th e maximum modeled ground

- level
concentration is below the PM 2.5 SILs and the differences between the background concentrations and the NAAQS are greater than the PM 2.5 SILs, a Full Impact Analysis would not be required. In this case,
the difference between the background concentrations and the NAAQS are greater than th e vacated

PM 2.5 SILs for both the annual and 24

- hour averaging periods (see table 7)

. Therefore, f or the RCTS Project

, a Full Impact Analysis is not required for PM 10 or PM 2.5

. D ue to the fact that the emissions beyond the facility boundary are insignificant, it is not expected that the construction or operation of the proposed RCTS P roject will have any adverse effect on ambient air quality.15 Table 7 PM 2.5 Background Concentrations

Pollutant Averaging

Period Background

Concentration (μg/m 3 ) 3 NAAQS

(μg/m 3 ) Difference

between NAAQS and Background (μg/m 3 ) SILs

(μg/m 3 )

PM 2.5 Annual 2.52 12 9.48 0.3

24

- hour 7.26 35 27.74 1.2

3

– Annual background concentration is based on 3

- year average of annual mean concentration for years 2010, 2011, and

2012. 24

- hour background concentration is based on 3

- year average of 98 th percentile concentration for years 2010, 2011,
and 2012 . All back ground data was obtained from the Glen Canyon monitoring site operated by SRP approximately 6 miles west of the NGS facility.

VII. Control Technology Review

EPA is required to conduct a case

- by

- case control technology review (CTR) pursuant to 40 CFR 49.154(c) to determine the appropriate level of pollution control for each pollutant subject to a minor NSR permit. This case

- by

- case control technology review is used to establish emission limitations for
the affected emissions units at the source

. An emission limitation means a requirement established by the reviewing authority that limits the quantity, rate or concentration of emission of air pollutants on a continuous basis, including any requirement relating to the operation or maint enance of a source to assure continuous emission reduction and any design standard, equipment standard, work practice, operational standard

, or pollution prevention technique.

As stated in 40 CFR 49.154(c), the case

- by

- case CTR considers the following fou r factors:

1. Local air quality conditions

2. Typical control technology or other emissions reduction measures used by similar sources in surrounding areas

3. Anticipated economic growth in the area

4. Cost

- effective emission reduction alternatives

Our final determination is not limited to the review process described below and may consider any
other relevant information related to the four CTR factors listed above.

A. Local Air Quality Conditions

The first step in the case

- by

- case CTR is to examine loca l air quality conditions and whether the proposed project is likely to have any effect on such conditions. The Air Quality Impact Analysis (AQIA) described in Section VI of this TSD outlines the process by which we determine whether the proposed project is likely to impact ambient air quality conditions. The area surrounding NGS is in attainment or unclassifiable for all National Ambient Air Quality Standards (NAAQS). The AQIA for the RCTS Project at NGS has shown that the expected emissions increases due t o the project are under all applicable SILs. Therefore, the proposed permit action is considered to have insignificant local air quality concerns.16

B. Anticipated Economic Growth in the Area

The second step in the case

- by

- case CTR process is to characterize the economic growth in the area by looking at population and population growth. If there is high population or population growth in an area, there may be some adverse impact on local ambient air quality.

The following data is taken from the U .S. Census Bureau for Coconino County, Arizona.

Coconino County, Arizona population in 2010: 134,421 Coconino County, Arizona population in 2000: 116,320 Percent change in population: +16 % Size of county: 18,661 mi 2 Current Population Density: 7 people /mi 2

The population in Coconino County has grown between 2000 and 2010 by about 16 percent. However,
the cou nty is very sparsely populated. Most of the population in Coconino County is centered in or
around Flagstaff (populati on 65,870 in 2010), Sedona, and Williams in the southern part of the county approximately 130 miles south of NGS . NGS is located in the more sparsely populated northern part of Coconino County. Page (population 7,247 in 2010) is the largest population center in the northern part of Coconino County. Page itself has had a six percent population growth between 2000 and 2010. The

RCTS P roject itself is not projected to increase economic growth in Coconino County. After review of this information, we have determined that there are no economic growth concerns due to the RCTS

P roject because the population in the area surrounding NGS is sparse and future economic growth is not expected to impact ambient air quality.

C. Equivalent Control Technologies

40 CFR 49.154(c)(4) requires that the reviewing authority assure that each affected emissions unit will comply will all requirements of 40 CFR P arts 60, 61, and 63 (NSPS/NESHAPS), as well as any Federal or Tribal Implementation Plans that apply to the unit.

As discussed above in Section III.C , there are currently two FIP s codified at 40 CFR 49.5513 (a)

– (i) and 49.5513(j) that apply to NGS. These FIPs contain emissions limits for criteria pollutants and also i nclud e limitations on du st emissions at 40 CFR 49.5513(d)(3). Under that provision, SRP was required to
submit a Dust Control Plan for NGS to EPA outlining dust suppression methods for controlling dust from existing coal handling and storage facilities, fly ash handling and stora ge, and road sweeping

activities. The Dust Control Plan has been included as an attachment to the most recent draft title V permit proposed by NNEPA in September 2015

. SRP is implement ing a variety of dust control measures

at NGS . We hav e ex amined these dust control techniques for the CTR of emissions associated with the

RCTS P roject.

The propos ed increase in emissions due to the RCTS is primarily a result of increased truck delivery traffic on existing unpaved roads at NGS . There will also be small incr eases in emissions from the new dust collectors to be installed on the RTCS, new baghouses associated with CKD storage silos and day
bins and very small increases from Units 1, 2, and 3 due to the increased ash content of the coal following the a pplication of CKD . However, SRP is not proposing to change the existing emission limits17

for Units 1, 2, and 3. Therefore, the CTR will focus on evaluation of emission limits for dust originating from unpaved roads, dust collectors, and baghouses.

SRP mitigates fugitive dust emissions at NGS due to truck delivery traffic on existing unpaved roads at
NGS by at least one of the following methods: applying daily water sprays, observing truck speed limits, restricting truck traffic flow, applying a gravel surface, an d chemical stabilization of the road surface.
SRP also mitigate s dust emissions from existing emission units, including coal handling and lime storage silos. Existing coal handling operations are controlled by fabric filter dust collectors. Weekly visible

emissions tests are conducted at coal handling dust collectors. If visible emissions are detected, then opacity r eadings conducted in accordance with EPA M ethod 9 are made and corrective action is taken
within 24 hours to ensure that no visible emissions a re detected. Limestone storage silos at NGS are similarly controlled by baghouses and subject to a requirement for weekly visible emissions tests as the coal handling dust collectors.

In this minor NSR permit, we are proposing to require SRP to limit the VMT for truck deliveries of CKD
and additional calcium bromide

, to water on roadways used for truck deliveries, as well as mitigate
visible emissions from the baghouses and dust collectors

. T he RCTS P roject is not expected to result in any local air qualit y concerns and there are not any economic growth concerns . Therefore, we are proposing that the control technologies described above which are currently in use at NGS would be sufficient to protect ambient air quality from further impacts due to the propos ed RCTS Project.

D. E mission Limits Determination

In our CTR for the proposed RCTS Project, we have determined that the control measures equivalent to
those used at comparable existing emission units at NGS are sufficient for the control of emission

increases from new emission units at the RCTS P roject. To control emissions from unpaved roads due
to increased CKD and calcium bromide truck delivery traffic, w e are proposing that a n operational limit

on VMT in a rolling 12

- month period is the most legally and practicably enforceable control measure.

EPA is propos ing to find that 720 VMT for CKD deliveries and that 70 VMT for calcium br omide deliveries are appropriate limits for any rolling 12

- month period. SRP will be required to record the
number of VMT for deliveries of each additive. In addition to limiting VMT for truck delivery traffic, we will require water spraying to the extent necessary to prevent fugitive dust emiss ions from unpaved
roads which exceed 20 percent opacity as measured using EPA Method 9. This opacity limit is consistent with that imposed on other activities at NGS through the facility’s title V permit. The potential to emit calculations for fugitive dus t emissions from unpaved roads due to the proposed RCTS Project are based on these proposed limits for VMT and the requirement to water the unpaved roads, assuming a control efficiency of 50%.

Fugitive dust emissions originating from roadways will also be mitigated by requiring SRP to implement work practice standards for loading of trucks with cement kiln dust in order to ensure that spillage or loss of material is minimized. If any spillage of cement kiln dust occurs on the roadway, it shall be
cleaned u p immediately. These work practice standards are consistent with those required at similar facilities in the region.

We have determined that fabric filter dust collectors and baghouse s proposed by SRP are sufficient control technology for the control of p articulate matter emissions , including PM 10 , from the RCTS , as18

well as for controlling the CKD storage silos and day bins

. To help control emissions from dust collectors and baghouses ass ociated with the proposed RCTS P roject, we are proposing that a weekly
emissions test on each emission unit by an individual trained in EPA Method 22 is sufficient to control excessive dust emissions. EPA Method 22 is a qualitative measurement to determine the presence or absence of visible emissions, which does not include the opacity measurement in EPA Method 9

. We have concluded that a weekly opacity measurement is not necessary due to the fact that i f visible emissions are detected during these weekly visible emissions tests, regardless of opacity, corrective

acti on will be required within 24 hours to eliminate the presence of visible emissions.

In addition to weekly visible emissions tests, we are proposing to require that SRP inspect and/or replace bags or filters for baghouses or dust collectors as often as necessary to ensure proper operation or more often as indicated by pressure differential readings or other indicators of filter failure. Baghouses and dust collectors are typically equipped with pressure different ial monitors which
indicate if the equipment is functioning properly or needs to be cleaned or replaced . SRP must keep an adequate supply of replacement bags and filters on site so that they may be replaced immedia tely upon the detection of failure. These monitoring techniques are consistent with those required for similar equipment throughout the country and are necessary to ensure that equipment is functioning properly and excess emissions of particulate matter ar e prevented.

VIII. Listed Spec ies

- r elated Requirements

EPA is responsible for complying with ESA Section 7 requirements with respect to federal Tribal Minor NSR permitting, and is the lead federal agency for Section 7(a)(2) compliance for the R CTS Project. EPA
has determined that the proposed action on SRP’s Tribal Minor NSR permit application for the R CTS Project is consistent with the substantive and procedural requirements of the ESA.

On November 20 , 2015, EPA initially sought concurrence from the Arizona U .S. Fish and Wildlife Service (Service) in the form of a letter for its finding that the R CTS P roject may affect, but is not likely to adversely affect, any federally

- listed endangered or threatened species or designated critical habitat for such species. However, after subsequent telephone conversations with the Service, EPA determined that there would be no effect due to the RCTS Project on any federally

- listed endangered or threatened species or critical habitat for such species. The Service wrote to EPA Region 9 in concurrence with this finding on December 18 , 2015.

Based on the information provided with SRP’s Tribal Minor NSR permit application for the R CTS Project, including the PM 10 modeling AQIA , the 2008 ESA Analysis, our recent communications with the Service concerning the R CTS Project, the fact that the c onstruction and operation of the R CTS Project
will occur solely within the existing boundary of the facility , EPA has concluded that our proposed
Tribal M inor NSR permit action for the p roject, specifically including consideration of the RCTS Project’s

increase in PM and PM 10 emissions will have no effect on any federally

- listed threatened or endangered species or designated critical habitat for such species, and no further action is nece ssary in
accordance with 50 CFR 402.13 (a)

.19

IX. Historic Properties

- r elated Requirements

EPA is responsible, as the lead federal agency for the R CTS P roject, for complying with the requirements under Section 106 of the National Historic Preservation Act by initiating consultation with the Navajo Nation Tribal Historic Preservation Officer, an undertaking, in accordance with 36 CFR

800.3. EPA initiated c onsultation with the Navajo Nation Historic Preservation Officer in writing on October 23, 2015.

The const ruction and operation of the NGS R CTS Project is considered a minor permit action under the Tribal NSR program and will be adding the RCTS to the existing coal handling operation. The effects of the proposed construction and operation will occur only within the existing footprint of the NGS. As such, the proposed area of potential effects (APE) includes the existing footprint of the NGS powe r plant. In addition, the incr eases in emissions due to this p roject do not exceed SILs beyond the existing facility boundary. Therefore, EPA expects no effects due to this proposed permit action on any historic properties or cultural resources which may e xist outside the NGS facility footprint.

EPA was advised by the Navajo Nation Tribal Historic Preservation Officer that the NGS facility itself is eligible for inclusion in the National Register of Historic Places. NGS has been in existence since the
earl y 1970’s and has been an integral part of the economy and community of Navajo Nation since that

time.

The area in which the construction of the NGS R CTS Project and associated infrastructure, such as the

CKD storage silos and new coal feed belt conveyors, is within the built

- up environment of the power plant. The area of the facility footprint has been mechanically excavated and leveled and contains an established complex of structures, roads, parking areas, and electrical lines to the degree that the area no longer resembles natural conditions.

The onsite construction and operation of the NGS R CTS Project will not diminish the integrity of the location, design, setting, materials, workmanship, feeling, or association of the NGS facility . While the
underta king will result in additional equipment at the plant, these changes are expected to be minimal and will not change the overall significance of NGS to the Navajo Nation.

Emissions of PM, PM 10 , and PM 2.5 associated with the NGS R CTS Project have the potent ial to impact visibility in the nearby area. Reduced visibility could adversely affect visual elements of NGS and the surrounding area. As such, EPA evaluated visibility impacts associated with the RCTS Project . EPA has determined that air impacts due to increased PM, PM 10 , and PM 2.5 emissions do not exceed the SILs or the NAAQS at the facility boundary. Therefore, there will be no effects due to the R CTS P roject on the visibility of the facility or the surrounding area.

X. Environmental Justice Analysis

On February 11, 1994, the President issued Executive Order 12898, entit led "Federal Actions to
Address Environmental Justice in Minority Populations and Low

- Income Populations." The Executive Order calls on each federal agency to make environmental justice a part of its mission by “identifying and addressing, as appropriate, disproportionately high and adverse human health or environmental effects of its programs, policies and activities on minority populations and low

- income populations.”20

The EPA defines “E nvironmental Justice” to include meaningful involvement of all people regardless of race, color, national origin, or income with respect to the development, implementation, and enforcement of environmental laws, regulations, and polices. The EPA’s goal is to address the needs of overburdened populations or communities to participate in the permitting process. Overburdened is used to describe the minority, low

- income, tribal and indigenous populations or communities in the United States that potentially experience disproportionate environmental harms and risks due to exposures or cumulative impacts or greater vulnerability to environmental hazards.

Based on the findings described in the memorandum dated November 24 , 2015, “Navajo Nation Indian

Reservatio n; Salt River Project, Navajo Generating Station Refined Coal Treatment System ; Environmental Justice,” we conclude that issuance of this m inor NSR permit is not expected to have disproportionately high or adverse human health effects on overburdened commu nities in the vicinity
of the fa cility on the Navajo Nation Reservation or in surrounding areas

.

This discussion describes the EPA’s efforts to identify potentially overburdened communities and assess potential effects in connection with issuing this prop osed m inor NSR permit for the RCTS Project

at NGS

.

A. Environmental Impacts to Potentially Overburdened Communities

This m inor NSR permit action authorizes the construction of new equipment and changes in operational standards which will cause an increase in air emissions of particulate matter at the NGS facility. The increased air emissions at the existing facility will not contribute to or cause any violation of the NAAQS. All emissions due to the RTCS P roject will be well controlled at all times and subject to federally enforceable permit conditions . This permit action will have no adverse ambient air quality impacts.

Furthermore, the existing PSD permit that was issued in 2008 contains provisions stating, “ At all times, including periods of startup, shutdown and malfunction, Permittee shall, to the extent practicable, maintain and operate the facility including associa ted air pollution control equipment in a manner consistent with good air pollution control practices for minimizing emissions

, ” and “ Permittee shall construct and operate this project in compliance with this PSD Permit, the application on which this

Permit is based, and all other applicable federal, state, and local air quality regulations. This PSD Permit does not release the Permittee from any liability for compliance with other applicable federal, state and local environmental laws and regulations, inclu ding the Clean Air Act. ” Noncompliance with these permit provisions is a violation of the permit and is grounds for enforcement action and for permit termination or revocation. As a result, the EPA concludes that proposed issuance of th is m inor NSR permit and incorporating its conditions into the existing PSD permit will not have disproportionately high or adverse human health effects on communities in the vicinity of the Navajo Nation Indian

Reservation.

B. Enhanced Public Participation

Given the presence o f potentially overburdened communities in t he vicinity of the NGS facility, we are providing an enhanced public participation process for this permit.21

1

. The m inor NSR permit application was submitted to both the EPA and NNEPA per the application instructions (see http://www3.epa.gov/air/tribal/tribalnsr.html ).

2

. NNEPA ha d 10 business days to communicate to u s any preliminary questions and comments on the application.

3 . In the event an Air Quality Impacts Analysis is necessary in addition to the initial application , we typically email a copy of tha t document to NNEPA within 5 business days from the date we receive it. This step was not necessary because t he applicant ha s attached the Air Quality Impact Analysis to the application and submitted it to NNEPA.

4 . We are notify ing NNEPA , other affected states and tribes, and other interested parties of the public comment period for the proposed minor NSR permit and provid ing copies of the notice of public comment opportunity to pos t in various locations on and around the Reservation. We will also notify

NNEPA , other affected states and tribes, and other interested parties of the issuance of the final permit.

XI. Authority

The Clean Air Act (CAA) provides EPA with broad authority to protect air resources throughout the nation, including air resources in Indian Country. Unlike States, Indian Tribes are not required to develop CAA new source review (NSR) permitting programs. See, e.g., Indian Tribes: Air Quality Planning and Management, 63 Fed. Reg. 7253 (Feb. 12, 1998) (also known as the Tribal Authority Rule)
codified at 40 CFR Part 49 . In the absence of an adequately implemented EPA

- approved NSR program on the Navajo Nation, EPA has the authority to implement a Federal Implementation Plan (FIP) in order to protect tribal air resources from impacts due to the construction of new or modified stationary sources of air pollutants. In 2011, EPA finalized the Tribal NSR Rule, codified at 40 CFR Part 49, as part of a FIP under the CAA for Indian Country. 76 Fed. Reg. 38748 (July 1, 2011). Among other requirements, the Tribal NSR Rule set forth procedures and terms under which the Agency would administer a minor NSR permitting program in Indian Country. Pursuant to Section 301(d)(4) of the CAA (42 U.S.C. Section 7601(d)), the EPA is authorized to implement the Tribal Minor NSR regulations
at 40 CFR 49.151 in Indian C ountry.

XII. Public Participation

A. Public Comment Period

In accordance with 40 CFR 49.157, we must provide public not ice and a 30

- day public comment period to ensure that the affected community and the general p ublic have reasonable access to the application and proposed permit information. The applica tion, the proposed permit, th is technical support document, and all other supporting materi als for the proposed permit are available for review

at:

Page Public Library
479 South Lake Powell Blvd Page, Arizona 86040 (928) 64 5

- 4270

Hours: Tues.

– Thurs. 9AM

– 8PM, Fri. 9AM

– 6PM, Sat. 10AM

– 6PM, Sun.

– Mon. Closed

Contact: Debbie Winlock, Director22

LeChee Chapter House 5 miles south on Coppermine Road LeChee, Arizona 86040 (928) 698

- 2800

Navajo Nation Environmental Protection Agency

Air Quality Control Program

Route 112, North Bldg. #2837

Fort Defiance, Arizona 86504 (928) 871‐6790

EPA Region 9 Air Permits Office (AIR

- 3)
75 Hawthorne Street San Francisco, CA 94105 (866) 372

- 9378

The administrative record for this action is available at http://www.regulations.gov / under docket ID
number EPA

- R09

- OAR

- 2016

- 0026 and is available for review at our office Monday through Friday from

9:00 a.m. to 4 :00 p.m. (excluding Federal holidays). Additionally, the proposed permit

, technical support document

, and supporting material can be reviewed on our website anytime during the public comment period at http://www2.epa.gov/caa

- permitting/tribal

- nsr

- permits

- region

- 9

. Any person may submit written comments on the proposed permit or EPA’s finding under this action
pursuant to Section 106 of the National Historic Preservation Act during the public comment period. These comments must raise any reasonably ascertainable issue s with supporting arguments by the close of the public comment period. Anyone may request a public hearing pursuant to 40 CFR 49.157(c) prior to the end of the public comment period. EPA accepts comments and requests for a public hearing by mail to the EPA a ddress listed above , on http://regulations.gov/ under docket ID number

EPA

- R09

- OAR

- 2016

- 0026, and via email to R9AirPermits@epa.gov

. In your written comments, please include the subject line: “Comments on Proposed Minor NSR Permit for SRP Navajo Generating
Station”.

B. Final Minor NSR Permit Action

In accordance with 40 CFR 49.159, a final permit becomes effective 30 days after permit issuance, unless: (1) a later effec tive date is specified in the per mit; or (2) appeal of the final permit is made as detailed in the next section; or (3) we may make the permit eff ective immediately upon issuance if no
comments resulted in a cha nge in the proposed permit or a denial of the permit. We will send notice of the final perm it action to any individual who commented on the proposed permit during the public comment period. I n addition, we will add the source to a list of final NSR permit actions wh ich is posted
on our website at http://www2.epa.gov/caa

- permitting/tribal

- nsr

- permits

- region

- 9 . Anyone may
request a copy of the final permit at any time by contacting the Region 9 Air Permits O ffice at R9AirPermits@epa.gov or by calling EPA Region 9’s toll

- free general information line at (866) 372

- 9378

.23

C. Appeals to the Environmental Appeals Board (EAB)

In accordance with 40 CFR 49.159, within 30 days after a final p ermit decision has been issued, any person who filed comments on the proposed permit or partici pated in the public hearing may petition the EAB to review any condition of the permit dec ision. The 30

- day period within which a person may request review under this section begins wh en the Region has fulfilled the notice requirements for the final permit decision. A petition to the EAB is, un der Section 307(b) of the Act, a prerequisite to seeking judicial rev iew of the final agency action. For purposes of judic ial review, final agency action occurs
when we deny or issue a final permit and agency review procedures are exhausted.