Mr. Robert Kaplan 

Acting Regional Administrator 

U.S. EPA, Region 5 

77 West Jackson Boulevard 

Chicago, IL 60604-3950 

Dear Mr. Kaplan: 

Re: State Implementation Plan Submittal for 

Indiana Regarding 1-Hour S02 Attainment 

A.B. Brown Generating Station in Posey 

County; Request for Parallel Processing 

(Commissioner's Order #2016-01) 

Pursuant to Section 110 of the Clean Air Act and Title 13 of the Indiana Code, the 

Indiana Department of Environmental Management (IDEM) submits a request for parallel 

processing of an amendment to the Indiana state implementation plan (SIP). IDEM 

requests that United States Environmental Protection Agency (U .S. EPA) approve the 

requirements for A.B. Brown Generating Station (A.B. Brown) in Commissioner's Order 

#2016-01. 

IDEM issued. a Commissioner's Order on January 11, 2016, to establish permanent 

and enforceable sulfur dioxide (S02) emission limits for A.B. Brown, located in Posey 

County, in order to ensure continued attainment of the 2010 1-hour sulfur dioxide (S02) 

standard in the area surrounding the facility. The Commissioner's Order contains 

emission limitations for Units 1 & 2, as well as reporting and recordkeeping requirements 

and method for compliance. The effective date for the emission limitations in the 

Commissioner's Order is April 19, 2016. It contains and meets the requirements set forth 

in 42 U.S.C. § 7407(d)(3)(E)(iii) and the conditions will become applicable requirements as 

defined in 326 lAC 2-7-1 (6). 

The rulemaking documentation is being forwarded to U.S. EPA with a request for 

parallel processing while IDEM completes the steps necessary for public notice. When the 

public notice process is complete, this SIP submittal will be supplemented with an 

addendum that includes the public notice documentation. The public notice period is 

scheduled to end on February 16, 2016. 

An Equal Opportunity Employer 0 A State that~ (!} Recycled Paper 
Throughout the development of this Commissioner's Order, staff of the Office of Air 

Quality worked closely with your staff to ensure that any potential problems that might 

exist with this requested state implementation plan revision would be resolved. I request 

that U.S. EPA approve this modification of Indiana's state implementation plan. If you 

have any questions or need additional information, please contact Scott Deloney, Chief, 

Air Programs Branch, at (317) 233-5694. 

KB/mad 

Attachments: Supporting Documents 

Sincerely, 

Keith Baugues 

Assistant Commissioner 

Office of Air Quality 

cc: Doug Aburano, U.S. EPA Region 5 (no enclosures) 

John Mooney, U.S. EPA Region 5 (no enclosures) 

Steve Rosenthal, U.S. EPA Region 5 (no enclosures) 

Pamela Blakley, U.S. EPA Region 5 (no enclosures) 

John Summerhays, U.S. EPA Region 5 (no enclosures) 

Keith Baugues, IDEM-OAQ (no enclosures) 

Scott Deloney, IDEM-OAQ (no enclosures) 

Mark Derf, IDEM-OAQ (no enclosures) 

Mike Mosier, IDEM-OAQ (no enclosure) 

Christine Pedersen, IDEM-OAQ (no enclosures) 

Jessica Reiss, IDEM-OAQ (no enclosures) 

File Copy 
Attachment C: Legal Notice of Public Hearing and Certificates of Web Publication 

Attachment D: Modeling Summary 

Data, calculations and methodology for determining 24-hour rolling average SOz 

emission limits based on A.B. Brown's continuous emission monitoring data (available 

upon request). 

Attachment A 

Administrative Checklist 

y 

g

; 

p

agreement ("document"); in final fotm. 

a. Date of adoption or final issuance: 

b. The effective date of the plan, if different 

from the adoption/issuance date. 

3. Evidence that the State has the necessary legal authority 

under state law to adopt and implement the plan. 

4. A copy of the actual regulation or document submitted for 

approval and incorporation by reference into the plan, 

including the following: 

a. Indication of the changes made to the existing 

approved plan, where applicable. 

b. The submittal shall be a copy of the official State 

regulation or document signed, stamped, dated by 

the appropriate state official indicating that it is fully 

enforceable by the State. Effective date shall be stated 

in the document itself. 

5. Evidence that the State followed all of the procedural 

requirements of the State's laws and constitution in 

conducting and completing the adoption/issuance ofthe plan. 

6. Evidence that public notice was given, including date of 

proof of publication. 

7. Certification that public hearings were held in accordance 

with information provided in public hearing notice. 

8. Compilation of public comments and State's response. 

9. Technical Support Document (if source specific change). 

January 11, 2016 

18 days after issuance 

IC 13-14-1-9 

IC 13-14-2-1 

Attachment B 

Attachment B 

Attachment C 

Include in Final Addendum 

Include in Final Addendum 

Attachment D 

Attachment B 

Commissioner's Order for A.B. Brown 

Generating Station addressing the 1-hour S02 

NAAQS 

Posey County 

IN THE MATTER OF: ) 

ORDER OF THE COMMISSIONER ) 

PURSUANT TO IC 13-14-2-1 ) 

FOR A.B. BROWN GENERATING STATION ) 

OF INDIANA ) 

) 

NOTICE AND ORDER OF THE 

COMMISSIONER OF THE 

DEPARTMENT OF ENVIRONMENTAL MANAGEMENT 

This Notice and Order of the Conunissioner of the Department of Environmental 

Management ("Order") is issued pursuant to Indiana Code ("IC") 13-14-1-9, IC 13-14-2-1, and 

IC 13-14-2-7. During the Commissioner's review, it was determined that the Petition should be 

granted according to the tenns specified below: 

PETITION 

Petitioner is Southern Indiana Gas and Electric Company (SIGECO) A.B. Brown 

Generating Station ("Petitioner"), a stationary electric power plant with Somce J.D. Number 

129-00010, located at 8511 Welborn Road in Mount Vernon, Posey County, Indiana, and 

permitted under the Pati 70 air operating permit program. 

On March 2, 2015, the U.S. District Comt for the Northern District of California accepted 

a Consent Decree between the U.S. Envirorunental Protection Agency ("U.S. EPA"), the Sierra 

Club, and the Natural Resources Defense Council to resolve litigation concerning deadlines for 

completing 1-hour sulfur dioxide ("S02") National Ambient Air Quality Standard ("NAAQS") 

designations. Under the Consent Decree, U.S. EPA must designate certain areas as 

nonattainment, attainment, or unclassifiable in tluee phases. 

The first Consent Decree phase requires U.S. EPA to designate areas that contain 

stationary sources that had not been announced for retirement as of March 2, 2015 and either 

emitted more than 16,000 tons of S02 in 2012 or emitted more than 2,600 tons of S02 and had an 

annual average emission rate of more than 0.45 pounds of S02 per one million British thermal 

units ("lb/MMBtu") in 2012, according to U.S. EPA's Air Quality Markets Database. 

On March 20, 2015, U.S. EPA identified five (5) sources in Indiana that met the criteria 

for the first phase of Consent Decree designations. U.S. EPA's list included the Petitioner, A.B. 

Brown Generating Station. 

An Equnl Opportunity Employer 0 (i) Recycled P11per A State ~ 
2 

On December 21, 2015, the Petitioner submitted a request to the Commissioner to impose 

permanent and enforceable S02 emission limitations and emission rates on the Petitioner in order 

to ensure continued attailll11ent of the S02 NAAQS in the area smTounding A.B. Brown 

Generating Station. · 

The Petitioner proposed S02 emission limitations, expressed in S02 lb/MMBtu, and 

emission rates, expressed in S02 pounds per hour ("lbllu·"), applicable to both Unit No. I and 

Unit No. 2, as follows: 

a. 0. 363 lb/MMBtu, twenty-four (24) hour rolling average; 

b. 183 I .61b/lu, twenty-four (24) hour rolling average; and 

c. 2152.2lb/hr, one (I) hour average. 

FINDINGS 

Pursuant to IC 13-14-2-l{b) aud IC 13-14-2-7(1), the Commissioner may issue Orders to 

secure compliance with Indiana's environmental statutes and rules, including the ambient air 

quality standard for S02 at 326 Indiana Administrative Code ("lAC") 1-3-4(b)(l)(A). 

Based on the foregoing information, IDEM finds the following: 

1. Pennanent and enforceable S02 emission limitations and emission rates for A.B. Brown 

Generating Station are required in order to model continued attainment of the !-hour S02 

NAAQS in the area sunounding the Petitioner. 

2. Adding S02 emission limitations and emission rates to the Petitioner's Part 70 Operating 

Permit is not adequately permanent to assure continued attainment of the S02 NAAQS. Instead, 

a Colllll1issioner's Order is required to ensure S02 emission limitations and emission rates 

remain permanent and enforceable, as required by 42 U.S.C. § 7407(d)(3)(E)(iii). 

3. Approval by U.S. EPA of the Conunissioner's Order into the Indiana State 

Implementation Plan ("SIP") is required to make Order requirements federally enforceable. 

Upon approval into the Indiana SIP, the Order requirements become applicable requirements as 

defined in 326 lAC 2-7-1(6). 

4. Based on modeling conducted by IDEM, the S02 emission limitations and emission rates 

proposed by the Petitioner must be clarified and adjusted in order to assure continued attainment 

of the SOz NAAQS. 
rates described below. 

2. When Unit No. 1 is operating alone, the unit shall not exceed 802 emission limitations 

and emission rates as follows: 

a. 2152.21b/ln·, one (I) hour average or emission rate of0.855 lb/MMBtu, one (1) 

hour average; and 

b. 1831.6 lb/hr, twenty-four (24) hour rolling average or emission rate of 0.727 

lb/MMBtu, twenty-four (24) hour rolling average. 

3. When both Unit No. 1 and Unit No. 2* are in operation, both units shall not exceed 

combined 802 emission limitations and emission rates as follows: 

a. 2152.2 lb/hr, one (I) hour average or emission rate of 0.426 lb/MMBtu, one (I) 

hour average; and 

b. 1831.6 lb/Ju·, twenty-four (24) hour rolling average or emission rate of 0.363 

lb/MMBtu, twenty-four (24) hour rolling average. 

4. When Unit No. 2* is operating alone, the unit shall not exceed S02 emission limitations 

and emission rates as follows: 

a. 1745.7lb/hr, one (1) hour average or emission rate of0.690 lb/MMBtu, one(!) 

hour average; and 

b. 1485.59 lb/Ju·, twenty-four (24) hour rolling average or emission rate of 0.588 

lb/MMBtu, twenty-four (24) hour rolling average. 

*Pursuant to PSD (65) 1355 issued on February 22, 1979, Unit No.2 shall not exceed an S02 

emission limitation of 0.69 lb/MMBtu, thirty (30) day rolling average. The S02 emission 

limitation applies to Unit No. 2 whenever Unit No. 2 is operating; this includes when Unit No. 2 

is operating alone and when both Unit No. 1 and Unit No. 2 are in operation. 

5. The Petitioner shall comply with the S02 emission limitations and emission rates 

beginning April 19, 2016. 

6. As required by 326 lAC 2-7-2(d)(l) and 326 IAC 2-7-5, the Petitioner shall apply to 

incorporate Order requirements, including reporting and recordkeeping requirements and 

methods to determine compliance, into its Part 70 Operating Permit within ninety (90) days of 

U.S. EPA approval of the Commissioner's Order into the Indiana SIP. 
a. Reporting: The Petitioner shall submit to IDEM, on a quarterly basis, a repmt of 

the daily maximum twenty-four (24) hour S02 rolling average for Unit No. I, for Unit 

No. 2, and for Unit No. I and Unit No. 2 combined. 

b. Recordkeeping: The Petitioner shall maintain records adequate to document 

compliance with the S02 emission limitations and emission rates. 

c. Method to determine compliance: Compliance shall be determined by a 

continuous emission monitoring system in accordance with 326 lAC 3-5. 

8. This Order shall apply to and be binding upon the Petitioner, its successors and assigns. 

No change in ownership, corporate, or partnership status of the Petitioner shall in any way alter 

its status or responsibilities under this Order. 

9. The requirements of this Order supersede any less stringent requirements applicable to 

the Petitioner. 

EFFECTIVE DATE OF ORDER 

Pursuant to IC 13-14-2-1(d), IC 4-21.5-3-1, IC 4-21.5-3-5(a)(6), and 40 Code of Federal 

Regulations ("CFR") 51.102, IDEM will give notice of this Order to each entity to whom the 

Order is directed and affected neighbors by mailing and to the general public by web publication. 

Pursuant to IC 4-21.5-3-7(a)(3), IC 4-21.5-3-2(e), and IC 4-21.5-3-5, this Order may be 

appealed by filing a Petition for review within eighteen (18) days after the date affected persons 

were given notice of the Order by U.S. mail. Information on petitions for review of this Order 

can be found at IC 4-21.5-3-7. 

Pursuant to IC 4-21.5-3-5(f) and IC 4-21.5-3-2(e), the Order is effective eighteen (18) 

days from mailing of notice unless a Petition for review has been filed before or on the 

eighteenth (181") day. However, the compliance date for the emission limitations in this Order is 

Aprill9, 2016. 

Pursuant to 40 CFR 51.103, IDEM will submit this Order to U.S. EPA as a revision to the 

Indiana SIP. Upon approval by the U.S. EPA, this Order will be part of the Indiana SIP. 

Persons seeking judicial review of this Order may do so in accordance with IC 4-21.5-5. 
Dated at Indianapolis, Indiana day of January, 2016. 

Commissioner 

Indiana Department of Environmental Management 

Attachment C 

Public Notice and Certificate of Publication for 

the Commissioner's Order for A.B. Brown 

Generating Station addressing the 1-hour S02 

NAAQS 

Posey County 

Commissioner's Order No 2016-01 

Notice is hereby given under 40 CFR 51.102 that the Indiana Department of Environmental 

Management ("IDEM") is accepting written comments and providing an opportunity for a public 

hearing regarding a revision to the Indiana state implementation plan (SIP) for Southern Indiana 

Gas and Electric Company, A.B. Brown Generating Station, Source I.D. Number 129-00010, 

located at 8511 Welborn Road in Mount Vernon, Posey County, Indiana. All interested persons 

are invited and will be given reasonable oppmiunity to express their views concerning the 

proposed revision to the SIP. 

The purpose of this notice is to solicit public connnent on a proposed revision to the SIP that is 

accomplished by Commissioner's Order No. 2016-01 for A.B. Brown Generating Station. The 

Commissioner's Order imposes sulfur dioxide emissions limits and emissions rates upon A.B. 

Brown Generating Station. This Commissioner's Order will be submitted to the United States 

Environmental Protection Agency ("U.S. EPA") for approval as a revision to the Indiana SIP. 

Any person may submit written comments on the proposed SIP revision. Written comments must 

be postmarked or delivered in person on or before February 16, 2016. 

Any person may request a public hearing on the proposed SIP revision. Requests for a public 

hearing must be submitted on or before February 16,2016. If no timely request for a public 

hearing is received, a hearing will not be held. If a hearing is scheduled, another legal notice will 

be published stating the date, time, and location of the meeting. Interested parties may present 

oral or written comments at the public hearing, if held. 

Comments and suppotiing documentation, or a request for a public hearing must be sent in 

writing to Mark Derf via the information provided below. Interested pmiies can also contact 

Mark Derfto see if a hearing has been scheduled. Please refer to Commissioner's Order 2016-01 

in all con·espondence. 

MarkDerf 

Indiana Depmiment of Environmental Management 

Office of Air Quality 

I 00 North Senate Avenue 

Mail Code 61-50 IGCN 1003 

Indianapolis, Indiana 46204 

Phone: (317) 233-5682 . 

Fax: (317) 233-2342 

E-mail: MDERF@idem.IN.gov. 
lOth Floor 

Indianapolis, Indiana 46204. 

and 

Indiana Department of Environmental Management 

Southwest Regional Office 

1120 Notth Vincennes Avenue 

Petersburg, Indiana 47567. 

and 

Alexandrian Public Library 

115 West Fifth Street 

Mount Vernon, Indiana 4 7620. 

The Commissioner's Order is also available on the IDEM website at: 

http://www.in.gov/idem/4686.htm. 

For additional information, please contact Mark Derf at the contact information provided above. 
MIDhfll R. Pen!lll 

(il.>..:nult 

(ll00)451-&127 • • 

January 13,2016 

CERTIFICATE OF PUBLICATION 

a. Comor 

This is to certify that the Indiana Department of Envirorunental Management (IDEM) notice of 

public comment period and opportunity for a Public Hearing regarding the following: 

• Commissione•·ts Order #2016-0l fo1· A.B. Bro1rn Gtntl'ating Station of Indiana 

was published on IDEM's web site on January 13,2016. It is that it will remain posted 

on the site until at least Febm:uy 16,2016. 

The notice in fnll was also made available the same day online at the following web address, 

under "Commissioner's Orden;"_ 

http://wmv.ingovlidem/4686.h1m 

Web publication of the notice was at the request of Scott Deloney, Branch Chief, Programs 

Branch, Office of Air Quality, IDEM. 

Attachments: 

Copy of web page as published 

All Eqn! Oppurtullity :Emplo-yw 

By: 

Mike Finklestein 

IDEM Webmaster 

Attachment D 

A.B. Brown Generating Station: 

Modeling Summary 

Posey County 

using Mercury and Air Toxics Standard (MATS) S02 compliance emission rates, was then 

provided in Indiana's Preliminary Recommendations Concerning Round 2 Air Quality 

Designations for the 20 I 0 Primary !-hour SOz Standard submitted to United States 

Environmental Protection Agency for review/consideration on September 16, 2015. 1 Since A.B. 

Brown decided to use the hydrochloric acid (HCl) emission limit to comply with the MATS 

instead of the SOz emission limits, those rates could not be used and would not satisfy the 

Consent Decree. As requested by A.B. Brown, IDEM issued a Commissioner's Order on 

January II, 2016, to establish permanent and enforceable sulfur dioxide (S02) emission limits 

for A.B. Brown in order to ensure continued attainment of the 2010 primary !-hour S02 standard 

in the area surrounding the facility. The Commissioner's Order contains emission limitations 

and emission rates for Units I & 2, as well as reporting and recordkeeping requirements and 

method for compliance. 

Modeled Limits 

The Commissioner's Order limits A.B. Brown's S02 emissions to 0.855 lbs S02/MMBtu 

(pounds per one million British thermal units) for Unit I and 0.69 lbs S02/MMBtu limit for Unit 

2 when operating alone based on a 1-hour S02 averaging time. Both units can never exceed 

2,152.2 lbs SOz/hr. (0.426 lbs SOz/MMBtu) when operating together. Therefore, Indiana 

modeled the S02 proposed emission limitations recommended by A.B. Brown. Five scenarios 

were modeled. Modeled concentrations for all five of A.B. Brown's operating scenarios were 

added to the temporally varying seasonal SOz background concentrations, as well as the emission 

limitations and emission rates for all five scenarios as outlined in Table 1. The worst case 

operating scenario was Scenario 5: Unit 2 operating at 0.69 lbs SOz/MMBtu and Unit I operating 

at 0.1611bs SOz/MMBtu. Again, both units, when operating, cannot exceed 2,152.2lbs S02/hr. 

Since that is the case, Unit I cannot operate at full capacity when Unit 2 is running at 0.69 lbs 

SOz/MMBtu. Also, when Unit 1 is operating at 0.855 lbs S02/MMBtu, Unit 2 cannot be 

operating. 

Table 1 

Scenaro 1 Scenario 2 Scenario 3 Scenario4 Scenario 5 

Group ID Emission Rate Bl BGAII Bl GOAII 43_AII B2 GOAII B2 69AII 

Boilerl lb/MMBtu 0.854725973 0.6 0.4275 0.256417792 0.161437649 

Boiler2 lb/MMBtu - 0.253517787 0.4275 0.595470356 0.69 

Boilerl Modeled lb/hr 2152.2 1510.8 1076.445 645.66 406.5 

Boiler2 Modeled lb/hr 641.4 1081.575 1506.54 1745.7 

Total lb/hr 2152.2 2152.2 2152.2 2152.2 2152.2 

Concentration 

ug/m3 188.64213 190.57711 193.45872 194.71424 195.51998 

1 http://www.in.gov/idem/airgualitv/2432.htm 

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