Year Total NOx (tons) Heat Input (MMBtu) Emission Rate

2001 34,019 191,638,695 0.355

2002 35,569 199,398,687 0.357

2003 31,620 183,478,417 0.345

2004 33,986 197,247,286 0.345

2005 33,221 191,786,039 0.346

2006 34,744 195,629,519 0.355

2007 35,253 196,676,299 0.358

2008 34,803 199,136,340 0.3495

2009 30,501 184,315,616 0.331

2010 24,427 173,473,615 0.282

2011 19,837 180,463,627 0.220

2012 16,468 164,966,570 0.200

AVG (01-08) 34,152 194,373,910 0.351

AVG (09-12) 175,804,857
This spreadsheet is from the proposed rulemaking, with the transcription error corrected in column C

Actual CAMD data

 Installation years

Avg of 01-08 34,152

final rule effective 

date of 1/1/2013

as reported in 

proposed rule, with 

transcription error

Step 1: with 

correction of 

transcription error

Step 2: PLUS with 

adjustment of final 

rule effective date 

to 12/31/13

Year

From proposal: 5-

yr BART as if LNB 

not yet installed

From Proposal 5 yr 

BART actual LNB 

install

5 yr BART actual 

LNB install

5 yr BART actual 

LNB install

install years by 2018 by 2018 by 2018 by 2018

2001 34,019 34,019 34,019 34,019

2002 35,569 35,569 35,569 35,569

2003 31,620 31,620 31,620 31,620

2004 33,986 33,986 33,986 33,986

2005 33,221 33,221 33,221 33,221

2006 34,744 34,744 34,744 34,744

2007 35,253 35,253 35,253 35,253

2008 34,803 34,803 34,803 34,803

2009 34,152 30,500 30,500 30,500

2010 34,152 24,427 24,427 24,427

2011 34,152 19,837 19,837 19,837

2012 34,152 23,325 23,325 23,325

2013 34,152 23,325 23,325 23,325

2014 34,152 23,325 23,325 23,325

2015 34,152 23,325 23,325 23,325

2016 34,152 23,325 23,325 23,325

2017 34,152 23,325 23,325 23,325

2018 5,345 5,343 5,345 23,325

2019 5,345 5,343 5,345 5,345

2020 5,345 5,343 5,345 5,345

2021 5,345 5,343 5,345 5,345

2022 5,345 5,343 5,345 5,345

2023 5,345 5,343 5,345 5,345

2024 5,345 5,343 5,345 5,345

2025 5,345 5,343 5,345 5,345

2026 5,345 5,343 5,345 5,345

2027 5,345 5,343 5,345 5,345

2028 5,345 5,343 5,345 5,345

2029 5,345 5,343 5,345 5,345

2030 5,345 5,343 5,345 5,345

2031 5,345 5,343 5,345 5,345

2032 5,345 5,343 5,345 5,345
2033 5,345 5,343 5,345 5,345

2034 5,345 5,343 5,345 5,345

2035 5,345 5,343 5,345 5,345

2036 5,345 5,343 5,345 5,345

2037 5,345 5,343 5,345 5,345

2038 5,345 5,343 5,345 5,345

2039 5,345 5,343 5,345 5,345

2040 5,345 5,343 5,345 5,345

2041 5,345 5,343 5,345 5,345

2042 5,345 5,343 5,345 5,345

2043 5,345 5,343 5,345 5,345

2044 5,345 5,343 5,345 5,345

sum (09-44) 451,689 358,974 359,028 377,008
Step 3: PLUS with 

LNB/SOFA credit

5-yr BART as if 

LNB not yet 

installed

by 2018

34,019

35,569

31,620

33,986

33,221

34,744

35,253

34,803

34,152

34,152

34,152

34,152

34,152

34,152

34,152

34,152

34,152

34,152

5,345

5,345

5,345

5,345

5,345

5,345

5,345

5,345

5,345

5,345

5,345

5,345

5,345

5,345
5,345

5,345

5,345

5,345

5,345

5,345

5,345

5,345

5,345

5,345

5,345

5,345

480,489
TWG used a different, but equivalent, method for applying the LNB/SOFA early installation credit compared to the metho

Example from Calculation in 2/5/13 Proposal, except that it does not propagate a transcription error in the original spreadshe

** Original spreadsheet inadvertantly, resulting from transcription error, used "5,343" instead of "5,345" in many cells

Avg of 01-08 34,152

Year

5-yr BART 

as if LNB 

not yet 

installed

5 yr BART 

actual 

LNB 

install

Alt 1

install years by 2018 by 2018 21/22/23

2001 34,019 34,019 34,019

2002 35,569 35,569 35,569

2003 31,620 31,620 31,620

2004 33,986 33,986 33,986

2005 33,221 33,221 33,221

2006 34,744 34,744 34,744

2007 35,253 35,253 35,253

2008 34,803 34,803 34,803

2009 34,152 30,500 30,501

2010 34,152 24,427 24,427

2011 34,152 19,837 19,837

2012 34,152 23,325 23,325

2013 34,152 23,325 23,325

2014 34,152 23,325 23,325

2015 34,152 23,325 23,325

2016 34,152 23,325 23,325

2017 34,152 23,325 23,325

2018 34,152 23,325 23,325

2019 5,345 5,345 23,325

2020 5,345 5,345 23,325

2021 5,345 5,345 17,332

2022 5,345 5,345 11,338

2023 5,345 5,345 5,345

2024 5,345 5,345 5,345

2025 5,345 5,345 5,345

2026 5,345 5,345 5,345

2027 5,345 5,345 5,345

2028 5,345 5,345 5,345

2029 5,345 5,345 5,345

2030 5,345 5,345 5,345

2031 5,345 5,345 5,345

2032 5,345 5,345 5,345

2033 5,345 5,345 5,345

2034 5,345 5,345 5,345

2035 5,345 5,345 5,345
2036 5,345 5,345 5,345

2037 5,345 5,345 5,345

2038 5,345 5,345 5,345

2039 5,345 5,345 5,345

2040 5,345 5,345 5,345

2041 5,345 5,345 5,345

2042 5,345 5,345 5,345

2043 5,345 5,345 5,345

2044 5,345 5,345 5,345

sum (09-44) 480,489 377,008 430,948

LNB credit 103,481

Adjusted Emissions with LNB Credit 327,467

EPA Method for Comparing Alternative to BART applied the LNB/SOFA Credit to the Alternative (via subtraction), such tha

Total 2009-2044 BART Emissions = 377,008

Adjsuted 2009-2044 Emissions from Alternative = 327,467

Emissions from Alternative are less than BART by: 49,541

TWG Method for Comparing Alternative to BART applied the LNB/SOFA Credit to the BART Threshold (cap) (via addition)* 

*(In other words, the BART Cap is calculated "as if" LNB/SOFA were not installed early at NGS and are installed concurrent

Total 2009-2044 BART Emissions = 480,489

Adjsuted 2009-2044 Emissions from Alternative = 430,948

Emissions from Alternative are less than BART by: 49,541

The resulting difference between BART and the Alternative to BART are equivalent using both methods.

Therefore, EPA's analysis of the TWG Alternatives in the following spreadsheets use the TWG Method and apply the LNB/S
redit compared to the method EPA used in the February 5, 2013 proposal

error in the original spreadsheet from 2/5/13 Proposal

of "5,345" in many cells
ve (via subtraction), such that

reshold (cap) (via addition)* instead of the Alternative, such that

 and are installed concurrently with new controls by BART compliance date)

Method and apply the LNB/SOFA credit to the BART Cap/Threshold
Actual CAMD data Avg NOx 01-08 34,152 NOx limit

 Closure or Installation years Avg Heat Input 01-12 188,184,226 Avg NOx rate 11-12

Avg Heat Input 01-08 194,373,910

Year

Actual 

Emissions

5-yr BART as 

if LNB not yet 

installed

BART

Glide Path to 

Cap

EST. TWG A1 EST. TWG A1

install years by 7/1/19 cumulative cumulative cumulative

2001 34,019 34,019 34,019

2002 35,569 35,569 35,569

2003 31,620 31,620 31,620

2004 33,986 33,986 33,986

2005 33,221 33,221 33,221

2006 34,744 34,744 34,744

2007 35,253 35,253 35,253

2008 34,803 34,803 34,803

2009 30,501 34,152 34,152 34,152 30,501 30,501

2010 24,427 34,152 68,304 47,316 24,427 54,928

2011 19,837 34,152 102,456 60,480 19,837 74,765

2012 16,468 34,152 136,608 73,645 16,468 91,233

2013 34,152 170,759 86,809 19,752 110,985

2014 34,152 204,911 99,973 19,752 130,737

2015 34,152 239,063 113,137 19,752 150,489

2016 34,152 273,215 126,301 19,752 170,241

2017 34,152 307,367 139,466 19,752 189,993

2018 34,152 341,519 152,630 19,752 209,745

2019 19,749 361,267 165,794 19,752 229,497

2020 5,345 366,613 178,958 13,168 242,665

2021 5,345 371,958 192,122 13,168 255,833

2022 5,345 377,303 205,287 13,168 269,001

2023 5,345 382,648 218,451 13,168 282,169

2024 5,345 387,994 231,615 13,168 295,337

2025 5,345 393,339 244,779 13,168 308,505

2026 5,345 398,684 257,944 13,168 321,674

2027 5,345 404,030 271,108 13,168 334,842

2028 5,345 409,375 284,272 13,168 348,010

2029 5,345 414,720 297,436 13,168 361,178

2030 5,345 420,065 310,600 13,168 374,346

2031 5,345 425,411 323,765 4,391 378,737

2032 5,345 430,756 336,929 4,391 383,128

2033 5,345 436,101 350,093 4,391 387,519

2034 5,345 441,447 363,257 4,391 391,910

2035 5,345 446,792 376,421 4,391 396,300

2036 5,345 452,137 389,586 4,391 400,691

2037 5,345 457,482 402,750 4,391 405,082
2038 5,345 462,828 415,914 4,391 409,473

2039 5,345 468,173 429,078 4,391 413,864

2040 5,345 473,518 442,243 4,391 418,255

2041 5,345 478,864 455,407 4,391 422,646

2042 5,345 484,209 468,571 4,391 427,037

2043 5,345 489,554 481,735 4,391 431,428

2044 5,345 494,899 494,899 4,391 435,819

sum (09-44) 494,899 435,819

AVG

slope 13,164
0.24

0.21
0

100,000

200,000

300,000

400,000

500,000

600,000

20092010201120122013201420152016201720182019202020212022202320242025202620272028202920302031203220332034203520362037203820392040204120422043204

4

Cumulative N

Ox Emissions

Year

Comparison of NOx Cap with TWG Alternative A1 (1 unit closes in 2020, 

no capacity increase, 2 units meet 0.07 lb/MMBtu in 2031) 

Glide Path to Cap

BART

EST. TWG A1

NOx Cap over 2009 - 2044
Actual CAMD data Avg NOx 01-08 34,152 NOx limit

 Closure or Installation years Avg Heat Input 01-12 188,184,226 Avg NOx rate 11-12

Avg Heat Input 01-08 194,373,910

TWG A2 = close one unit with capacity increase up to 189 MW (19 MW + max 170 MW - depends on how much of NGS Nav

TWG A3 = curtail one unit by no less than 561 MW (Based on shares of (LADWP+NVE - Navajo Nation)=> 477 + 254 - (max o

Year

Actual 

Emissions

5-yr BART as 

if LNB not yet 

installed

BART

Glide Path to 

Cap

EST. TWG A2 EST. TWG A2

install years by 7/1/19 cumulative cumulative cumulative

2001 34,019 34,019 34,019

2002 35,569 35,569 35,569

2003 31,620 31,620 31,620

2004 33,986 33,986 33,986

2005 33,221 33,221 33,221

2006 34,744 34,744 34,744

2007 35,253 35,253 35,253

2008 34,803 34,803 34,803

2009 30,501 34,152 34,152 34,152 30,501 30,501

2010 24,427 34,152 68,304 47,316 24,427 54,928

2011 19,837 34,152 102,456 60,480 19,837 74,765

2012 16,468 34,152 136,608 73,645 16,468 91,233

2013 34,152 170,759 86,809 19,752 110,985

2014 34,152 204,911 99,973 19,752 130,737

2015 34,152 239,063 113,137 19,752 150,489

2016 34,152 273,215 126,301 19,752 170,241

2017 34,152 307,367 139,466 19,752 189,993

2018 34,152 341,519 152,630 19,752 209,745

2019 19,749 361,267 165,794 19,752 229,497

2020 5,345 366,613 178,958 14,827 244,325

2021 5,345 371,958 192,122 14,827 259,152

2022 5,345 377,303 205,287 14,827 273,979

2023 5,345 382,648 218,451 14,827 288,806

2024 5,345 387,994 231,615 14,827 303,633

2025 5,345 393,339 244,779 14,827 318,461

2026 5,345 398,684 257,944 14,827 333,288

2027 5,345 404,030 271,108 14,827 348,115

2028 5,345 409,375 284,272 14,827 362,942

2029 5,345 414,720 297,436 14,827 377,769

2030 5,345 420,065 310,600 14,827 392,597

2031 5,345 425,411 323,765 4,944 397,541

2032 5,345 430,756 336,929 4,944 402,485

2033 5,345 436,101 350,093 4,944 407,429

2034 5,345 441,447 363,257 4,944 412,373

2035 5,345 446,792 376,421 4,944 417,318

2036 5,345 452,137 389,586 4,944 422,262
2037 5,345 457,482 402,750 4,944 427,206

2038 5,345 462,828 415,914 4,944 432,150

2039 5,345 468,173 429,078 4,944 437,095

2040 5,345 473,518 442,243 4,944 442,039

2041 5,345 478,864 455,407 4,944 446,983

2042 5,345 484,209 468,571 4,944 451,927

2043 5,345 489,554 481,735 4,944 456,871

2044 5,345 494,899 494,899 4,944 461,816

sum (09-44) 494,899 461,816

AVG

slope 13,164

** TWG A2 and A3 result in equivalent MW reductions

i.e., assuming Navajo Nation elects to purchase 170 MW, and capacity icnrease also include 19 MW to make up for LADWP 

Under A2, close one unit, increase capacity by 170 + 19 MW = capacity reduction of 750 - 170 MW - 19 MW = 561 MW

Under A3, curtail one unit by LADWP + NVEnergy - Navajo Nation share = 477 + 254 - 170 = 561 MW
0.24

0.21

on how much of NGS Navajo Nation buys)

tion)=> 477 + 254 - (max of 170) MW = 561 MW
W to make up for LADWP and NV Energy shortfall from 1 750 MW unit

W - 19 MW = 561 MW
0

100,000

200,000

300,000

400,000

500,000

600,000

20092010201120122013201420152016201720182019202020212022202320242025202620272028202920302031203220332034203520362037203820392040204120422043204

4

Cumulative N

Ox Emissions

Year

Comparison of NOx Cap with TWG Alternative A2 and A3 (1 unit closes 

plus maximum capacity increase (189 MW), or curtailment of 561 MW, 

in 2020; and 2 units meet 0.07 lb/MMBtu in 2031)

Glide Path to Cap

BART

Est TWG A2 or A3

NOx Cap over 2009 - 2044
Actual CAMD data Avg NOx 01-08 34,152

 Installation years Avg Heat Input 01-12 188,184,226 Avg NOx rate 11-12

Avg Heat Input 01-08 194,373,910

Year

Actual 

Emissions

5-yr BART as 

if LNB not yet 

installed

BART

Glide Path to 

Cap

Alt B Alt B

install years by 7/1/19 cumulative cumulative Est cumulative

2001 34,019 34,019

2002 35,569 35,569

2003 31,620 31,620

2004 33,986 33,986

2005 33,221 33,221

2006 34,744 34,744

2007 35,253 35,253

2008 34,803 34,803

2009 30,501 34,152 34,152 34,152 30,501

2010 24,427 34,152 68,304 53,288 24,427

2011 19,837 34,152 102,456 72,423 19,837

2012 16,468 34,152 136,608 91,559 23,325

2013 34,152 170,759 110,695 23,325

2014 34,152 204,911 129,830 23,325

2015 34,152 239,063 148,966 23,325

2016 34,152 273,215 168,101 23,325

2017 34,152 307,367 187,237 23,325

2018 34,152 341,519 206,373 23,325

2019 19,749 361,268 225,508 23,325

2020 5,345 366,613 244,644 15,550

2021 5,345 371,958 263,780 15,550

2022 5,345 377,304 282,915 15,550

2023 5,345 382,649 302,051 15,550

2024 5,345 387,994 321,187 15,550

2025 5,345 393,339 340,322 15,550

2026 5,345 398,685 359,458 15,550

2027 5,345 404,030 378,594 15,550

2028 5,345 409,375 397,729 15,550

2029 5,345 414,720 416,865 15,550

2030 5,345 420,066 422,067

2031 5,345 425,411 427,270

2032 5,345 430,756 432,472

2033 5,345 436,101 437,674

2034 5,345 441,447 442,876

2035 5,345 446,792 448,079

2036 5,345 452,137 453,281

2037 5,345 457,482 458,483

416,865
2038 5,345 462,828 463,686

2039 5,345 468,173 468,888

2040 5,345 473,518 474,090

2041 5,345 478,864 479,292

2042 5,345 484,209 484,495

2043 5,345 489,554 489,697

2044 5,345 494,899 494,899

sum (09-44) 494,899

slope (2029 cap) 19,136

slope (2044 cap) 5,202

494,899
NOx limit 0.24

Avg NOx rate 11-12 0.21

Est. 3 SCR 

meeting 

0.055

Est. 3 SCR 

meeting 

0.055

Est. 3 SCR 

meeting 

0.07

Est. 3 SCR 

meeting 

0.07

cumulative cumulative

30,501 30,501 30,501 30,501

24,427 54,928 24,427 54,928

19,837 74,765 19,837 74,765

16,468 91,233 16,468 91,233

19,752 110,985 19,752 110,985

19,752 130,737 19,752 130,737

19,752 150,489 19,752 150,489

19,752 170,241 19,752 170,241

19,752 189,993 19,752 189,993

19,752 209,745 19,752 209,745

19,752 229,497 19,752 229,497

19,752 249,249 19,752 249,249

19,752 269,001 19,752 269,001

19,752 288,753 19,752 288,753

19,752 308,505 19,752 308,505

19,752 328,258 19,752 328,258

19,752 348,010 19,752 348,010

19,752 367,762 15,874 363,883

19,752 387,514 11,338 375,222

15,388 402,902 6,803 382,025

10,367 413,268 6,803 388,828

5,345 418,613 6,803 395,631

5,345 423,959 6,803 402,434

5,345 429,304 6,803 409,237

5,345 434,649 6,803 416,040

5,345 439,995 6,803 422,844

5,345 445,340 6,803 429,647

5,345 450,685 6,803 436,450

5,345 456,030 6,803 443,253
5,345 461,376 6,803 450,056

5,345 466,721 6,803 456,859

5,345 472,066 6,803 463,662

5,345 477,412 6,803 470,465

5,345 482,757 6,803 477,268

5,345 488,102 6,803 484,071

5,345 493,447 6,803 490,874
0

100,000

200,000

300,000

400,000

500,000

600,000

20092010201120122013201420152016201720182019202020212022202320242025202620272028202920302031203220332034203520362037203820392040204120422043204

4

Cumulative N

Ox Emissions

Year

Comparison of Nested NOx Caps with TWG Alternative B (assuming 

installation of 3 SCR to meet Nested Caps) 

Glide Path to Cap

BART

Est. 3 SCR meeting 0.055

Est. 3 SCR meeting 0.07

NOx Cap over 2009 - 2044

NOx Cap over 2009 - 2029
Unit # Year

2009 3 2009

2010 2 2010

2011 1 2011

2012 3 2012

2013 2 2013

2014 1 2014

2015 3 2015

2016 2 2016

2017 1 2017

2018 3 2018

2019 2 2019

2020 1 2020

2021 3 2021

2022 2 2022

2023 1 2023

2024 3 2024

2025 2 2025

2026 1 2026

2027 3 2027

2028 2 2028

2029 1 2029

Major

Major

Minor

Major

Minor

Major

Minor