i

NATIONAL EMISSIONS STANDARDS FOR HAZARDOUS AIR POLLUTANTS:

PORTLAND CEMENT

SUMMARY OF PUBLIC COMMENTS AND RESPONSES

U.S. Environmental Protection Agency

Office of Air Quality Planning and Standards

Sector Policies and Programs Division

Research Triangle Park, North Carolina 27711

12 20 2012
ii

The primary contact regarding questions or comments on this document is:

Sharon Nizich

U.S. Environmental Protection Agency

Metals and Minerals Group (D243-02)

Research Triangle Park, North Carolina 27711

Email: Nizich.Sharon@epa.gov
iii

Table of Contents

Section Page

Table of Contents.......................................................................................................................................iii

List of Acronyms and Abbreviations ........................................................................................................x

Introduction................................................................................................................................................xi

List of Commenters...................................................................................................................................xii

Section 1: Comments on Regulatory Deadlines and EPA Authority .....................................................1

1.1 One-Year Compliance Deadline Extension........................................................................................1

1.2 Two-Year Compliance Deadline Extension .......................................................................................2

Three-Year Compliance Deadline Extension...........................................................................................9

1.3 Authority to Reset Compliance Date..................................................................................................9

1.4 Extension of Altered Compliance Deadline to All NESHAP Standards..........................................13

1.5 New Source Applicability Date........................................................................................................17

Section 2: Comments on Definitions........................................................................................................19

2.1 Open Clinker Storage Pile Definition...............................................................................................19

2.2 Inline Coal Mill Definition...............................................................................................................20

2.3 Raw Material Dryer Definition.........................................................................................................21

2.4 Start-up/Shutdown Definition...........................................................................................................21

2.5 Kiln Operation Definition.................................................................................................................25

Section 3: Comments on Emission Standards/Limits............................................................................26

3.1 Particulate Matter (PM): General Support and Opposition for the Standard ...................................26
iv

3.2 PM: Clarification on Stack Test to be used ......................................................................................26

3.3 PM: UPL Calculation Method Under-predicts Variability...............................................................27

3.4 PM: Exemption from Operating Surrogate Limit for BACT and CAM CEMS Units.....................28

3.5 PM: Standard should not Apply to Modifications Made to an Existing Kiln and or Cooler............29

3.6 PM: Standard should not be Changed Until CISWI Rule is Finalized.............................................29

3.7 PM: Abandonment of PM CEMS Due to PS-11 Issues is Unlawful................................................31

3.8 PM: Utilization of the UPL Method is Unlawful and does not Account for Operator Efforts.........33

3.9 PM: Selection of Best Performing Sources was done Incorrectly...................................................35

3.10 PM: Rounding-up of UPL is Unlawful..........................................................................................36

3.11 PM: Comment Regarding Lack of PM Data for Kilns...................................................................36

3.12 PM: Beyond the Floor Rejection due to Cost Effectiveness is Unlawful.......................................37

3.13 Mercury (Hg): Opposition to Beyond the Floor Standard..............................................................39

3.14 Hg: Opposition to EPA’s Process of Setting the Standard.............................................................39

3.15 Hg: Significant Cost Should Negate Beyond the Floor, Limit is Unachievable ............................40

3.16 Hg: Environmental and Energy Impacts Have Not Been Evaluated..............................................40

3.17 Hg: Comment Regarding 63.1349(b)(5)(ii)....................................................................................42

3.18 Hg: General Support.......................................................................................................................42

3.19 Total Hydrocarbon (THC): Support for Including Union Bridge CISWI Kiln ..............................42

3.20 THC: Opposition to Including Union Bridge CISWI Kiln.............................................................43

3.21 Organic Hazardous Air Pollutants (oHAP) Alternative to THC: General Support........................44

3.22 o-HAP Alternative to THC: Use of Three Times the RDL is Unlawful ........................................45

3.23 oHAP Alternative to THC: Significant Opposition to the Use of Three Times the RDL ..............46

3.24 Hydrogen Chloride (HCl): General Support of Standard...............................................................49

3.25 Start-up/Shutdown: Opposition to Numerical Standards / Support for Work Practices.................49
v

3.26 Start-up/Shutdown: Support for Numerical Standards / Opposition to Work Practices.................51

3.27 Start-up/Shutdown: Opposition to Steady State Limits Being Applied Start-up/Shutdown ..........52

3.28 Start-up/Shutdown: Justification for Suggested Work Practices....................................................54

3.29 Start-up/Shutdown: Support for Recordkeeping ............................................................................54

3.30 Start-up/Shutdown: HCl Limit During Start-up and Shutdown .....................................................54

3.31 Clinker Piles: Additional Authorized Work Practices....................................................................55

3.32 Coal Mills/Alkali By-pass Stacks: General Support ......................................................................56

3.33 Coal Mills/Alkali By-pass Stacks: Standard is Unlawful because no Data has been Collected.....56

3.34 Coal Mills/Alkali By-pass Stacks: Request for More Time to Respond ........................................56

3.35 Coal Mills/Alkali By-pass Stacks: Backsliding with PM NSPS Option ........................................57

3.36 Coal Mills/Alkali By-pass Stacks: Alternative PM Standard.........................................................58

3.37 Raw Material Dryers: Support for Eliminating O2 Correction Factor...........................................58

Section 4: Comments on Monitoring Requirements..............................................................................59

4.1 Particulate Matter (PM): Opposition to Testing-based Standard......................................................59

4.2 PM: Request for Compliance Margin (Scaling) between Tested Value and Limit ..........................62

4.3 PM: Request for Language Revision................................................................................................64

4.4 PM: Request to Remove Testing Requirement Following CPMS ...................................................66

4.5 PM: Request for Reduced Testing Frequency due to Financial Burden...........................................66

4.6 PM: Request for COMS as a Parametric Monitor............................................................................67

4.7 PM: Suggested Corrections to PS 11 Issues.....................................................................................67

4.8 PM: Inconsistency between Length of Test Runs ............................................................................68

4.9 PM: Request for Beta Gauge PM Monitors or Multi Metal CEMS Options for Monitoring...........68

4.10 PM: Bag Leak Detection as a Parametric Monitor.........................................................................70

4.11 PM: Four CPMS Deviations in 12 Months Does Not Equate to a Violation .................................71
vi

4.12 PM: Clinker Production Monitoring...............................................................................................72

4.13 PM: Comment Regarding 63.1343(b) ............................................................................................72

4.14 PM: Comment Regarding 60.64(b)(1)(ii), 63.1349(b)(1)(i)(B), and 63.1350(b)(1) ......................73

4.15 PM: Comment Regarding 60.64(b)(1)(iii) and63.1349(b)(1)(i)(C)................................................73

4.16 PM: Comment Regarding 63.1350(b)(1)(iii)..................................................................................74

4.17 PM: Comment Regarding 63.1350(b)(1)(iv)..................................................................................74

4.18 PM: Comment Regarding 63.1349(b)(1)(ii) and (iv) .....................................................................75

4.19 PM: Comment Regarding 63.1350(b)(2)........................................................................................75

4.20 Hydrogen Chloride (HCl): General Support for Proposed Standard..............................................76

4.21 HCl: Opposition to HCl CEMS and PS 15.....................................................................................76

4.22 HCl: Comment on Pending Performance Specifications................................................................80

4.23 HCl: On-going Quality Assurance Requirements are Premature ...................................................80

4.24 HCl: Span Calibration Requirements.............................................................................................81

4.25 HCl: Above Span Calibration Requirements..................................................................................82

4.26 HCl: Opposition to Elimination of CEMs for Dry Scrubbers ........................................................84

4.27 HCl: Opposition to SO2 CEMS......................................................................................................84

4.28 HCl: Comment Regarding Part 63 Appendix A.............................................................................85

4.29 HCl: Comment Regarding 63.1349(b)(6)(i)(B) and 63.1350(1)(2) and (m)(5)(7) and (8) ............86

4.30 HCl: Comment Regarding 63.1348(a)(6)(iv), 63.1349(b)(6)(iii), and 63.1350(1)(3)....................87

4.31 Hg: Opposition to Quality Assurance of Hg CEMS Data (Options 1 and 2).................................89

4.32 Hg: Opposition to Cycle Time Test................................................................................................91

4.33 Hg: Modification to Quality Assurance of Hg CEMS Data (Option 3) .........................................92

4.34 Hg: Request to Monitor Upstream or Downstream of a Coal Mill Receiving Kiln Exhaust .........94

4.35 Hg: Request that Emissions During D/F Temperature Parameter Tests are not Considered 

“Normal Operations”..................................................................................................................95
vii

4.36 Hg: Request to Forego 30-month D/F Testing if it Will Impair Performance of Hg Controls.......96

4.37 Hg: Comment Regarding 63.1350(k) and (k)(3) and (4)................................................................96

4.38 Hg: Comment Regarding 63.1348(a)(5) and (b)(7) and 163.350(k)(3) and (k)(6).........................97

4.39 Hg: Comment Regarding 63.1346(f)..............................................................................................98

4.40 Start-up/Shutdown: PM Monitoring...............................................................................................98

4.41 Start-up/Shutdown: Hg Monitoring................................................................................................99

4.42 Start-up/Shutdown: Moisture Corrections....................................................................................100

4.43 Start-up/Shutdown: HCl Monitoring...........................................................................................100

4.44 Start-up/Shutdown: Effluent Flow Rate Monitoring ....................................................................101

4.45 Start-up/Shutdown: Emissions Testing Issues.............................................................................102

4.46 Start-up/Shutdown: Opposition to Record Keeping in Lieu of CEMS for Compliance 

Demonstration ..........................................................................................................................104

4.47 Dioxin/Furan: Monitoring of Carbon Injection Rates.................................................................104

4.48 THC and oHAP Alternative: Opposition to Annual Testing Requirement .................................106

4.49 THC and oHAP Alternative: Request for Five Year (60 months) Testing Frequency for Raw 

Material Dryers, Coal Mills and Alkali Bypass Stacks............................................................107

4.50 THC and oHAP Alternative: Support for Extending Testing Time and Number of Tests to 

Adequately Capture Variability................................................................................................110

4.51 THC and oHAP Alternative: Request for Compliance Margin (Scaling) between Tested Value and 

Limit .........................................................................................................................................112

4.52 THC and oHAP Alternative: Suggestions for Rule Improvement ...............................................114

4.53 THC and oHAP Alternative: General Support.............................................................................116

4.54 THC: Comment Regarding 63.1349(b)(4) and 63.1350(i)...........................................................116

4.55 Coal Mills/Alkali Bypass: General Support .................................................................................116

4.56 Coal Mills/Alkali Bypass: Correction to Kiln Gas Diversion Equation.......................................117

4.57 Coal Mills/Alkali Bypass: Request for Site Specific Monitoring Programs for Coal Mills........117
viii

4.58 Coal Mills/Alkali Bypass: Request for Additional Time to Comment.........................................118

4.59 Coal Mills/Alkali Bypass: Promulgation of Coal Mill Requirements would be Unlawful..........118

4.60 Coal Mills/Alkali By-pass Stacks: Issue with Upstream Monitoring of THC and HCl for Comingled Streams.......................................................................................................................120

4.61 Clinker Piles: Installation of Ambient Monitors ..........................................................................120

Section 5: Comments on Affirmative Defense......................................................................................122

5.1 Affirmative Defense: General Support...........................................................................................122

5.2 Affirmative Defense: Opposition to General Rationale .................................................................122

5.3 Affirmative Defense: Assessment of Penalties (113(e) and 304)...................................................124

5.4 Affirmative Defense: Burden and Duplication Issues....................................................................126

5.5 Affirmative Defense: Rebuttable Presumption...............................................................................127

5.6 Affirmative Defense: Suggested Revisions....................................................................................127

5.7 Affirmative Defense: Ferroalloys MACT Comments Incorporated by Reference.........................128

5.8 Affirmative Defense: Opposition to Independent Mandates to Qualify for the Defense ..............135

5.9 Affirmative Defense: Bypassing Control Equipment.....................................................................136

5.10 Affirmative Defense: Root Cause.................................................................................................136

Section 6: Comments on Impacts of the Rule.......................................................................................143

6.1 Impacts: ACI Cost Estimate Inaccurate..........................................................................................143

6.2 Impacts: PM Incremental Risk to Public Health ............................................................................143

Section 7: Comments Regarding Miscellaneous Other Issues............................................................144

7.1 Other Issues: Request to Reorganize Rule......................................................................................144

7.2 Other Issues: Request to Remove Flow Monitor Requirement for NSPS.....................................144

7.3 Other Issues: Clarification on Averaging Periods for NSPS.........................................................144

7.4 Other Issues: Proposed Administrative Correction to § 63.1343(b)...............................................145

7.5 Other Issues: Proposed Administrative Correction to § 63.1344(A)(1)(III)(2)..............................145
ix

7.6 Other Issues: Proposed Administrative Correction to § 63.1350(k)(4)..........................................146

7.7 Other Issues: Proposed Administrative Correction to § 63.1350(m)(4).........................................146

7.8 Other Issues: Proposed Regulatory Text Changes, Refer to (0505) Appendix G .........................146

7.9 Other Issues: Request for Testing and Monitoring Exemptions for Small/Area Sources ..............147

7.10 Other Issues: Duplication of Reporting Requirements.................................................................147

7.11 Other Issues: Comment Regarding 63.1343(a) ............................................................................148

7.12 Other Issues: Comment Regarding 63.1348(a) and 63.1349(b)...................................................149

7.13 Other Issues: Comment Regarding 60.64(b)(2) and (3)...............................................................149

7.14 Other Issues: Comment Regarding 63.1350(f)(1)(iv) ..................................................................150

7.15 Other Issues: Comment Regarding 60.64(c) ................................................................................150

7.16 Other Issues: Comment Regarding 63.1343.................................................................................151

7.17 Other Issues: Comment Regarding 63.1350(o)(4&5) ..................................................................151

7.18 Other Issues: Comment Regarding 63.1350(1) and 63.1350(m)..................................................152

7.19 Other Issues: Comment Regarding 63.1340(b)(6) and 63.1345...................................................153

7.20 Other Issues: Comment Regarding 63.1340(b)............................................................................153

7.21 Other Issues: Comment Regarding THC and Greenfield/Brownfield Dryers..............................154

7.22 Other Issues: Comment Regarding EPA Rationale and Authority for Startup and Shutdown 

Provisions and Revising SSM Provisions in Existing Rules....................................................154

Section 8: Comments Regarding General Support and Opposition to the Proposed Rule..............161

8.1 General Support for Proposed Standards........................................................................................161

8.2 General Support for Many of the Proposed Standards with Some Specific Concerns...................161

8.3 General Opposition to Weakening of Standards ............................................................................162

8.4 General Opposition – Mass Email Campaigns...............................................................................162
x

List of Acronyms and Abbreviations

CAA Clean Air Act

CBI Confidential Business Information

CRWI Coalition for Responsible Waste Incineration

D/F Dioxins and Furans

EPA U. S. Environmental Protection Agency

ERT Electronic Reporting Tool

FAX Fascimile

FR Federal Register

HAP Hazardous Air Pollutant

HF Hydrogen Fluoride

HON Hazardous Organic NESHAP

MACT Maximum Achievable Control Technology

MIR Maximum Individual Risk

MOA Mode of Action

NAAQS National Ambient Air Quality Standards

NATA National-Scale Air Toxics Assessment

NESHAP National Emission Standards for Hazardous 

Air Pollutants

NFFS Non-Ferrous Founders’ Society

OGC Office of General Counsel

OM&M Operation, Maintenance and Monitoring

PB-HAP Persistent Bioaccumulative Hazardous Air 

Pollutant

PSD Prevention of Significant Deterioration

RTR Risk and Technology Review

SAPU Secondary Aluminum Processing Unit

SIP State Implementation Plan

SSM Startup, Shutdown, and Malfunction

TTN Technology Transfer Network

URE Unit Risk Exposure
xi

Introduction

On July 18, 2012, EPA proposed revisions to the National Emission Standards for 

Hazardous Air Pollutants (NESHAP) for Portland Cement Plants as well as limited amendments 

to the New Source Performance Standard for particulate matter. This document contains 

summaries of all the public comments that the EPA received on the proposed standards. 

Significant comments and responses appear in the preamble to the final rules. Responses to all 

other comments are contained in this document. Copies of all comments submitted are available 

at the EPA docket Center Public Reading Room. Comment letters and transcripts of the public 

hearings are also available electronically through http://www.regulations.gov by searching 

Docket IDs EPA-HQ-OAR-2011-0817.
xii

List of Commenters

The EPA received over 22,000 comment letters on the proposed NESHAP for portland 

cement plants before the comment period closed on August 17, 2012. All comments are 

contained in Docket EPA-HQ-OAR-2011-0817. The commenter, affiliation, and item number in 

Docket EPA-HQ-OAR-2011-0817 is listed below in Table 1.

Table 1. Public Comments for Portland Cement, Proposed Rule, Docket EPA-HQ-OAR2011-0817

Docket No. 

EPA-HQOAR-2011-

0817 Commenter Name Affiliation

0241 Anonymous public comment Private Citizen Comment

0242 Anonymous public comment Private Citizen Comment

0243 Anonymous public comment Private Citizen Comment

0244 Anonymous public comment Private Citizen Comment

0245 Jennifer Anderson Anderson Psychological Associates

0246 Anonymous public comment Private Citizen Comment

0247 Anonymous public comment Private Citizen Comment

0249 Anonymous public comment Private Citizen Comment

0250 Walter H. Wulf, Jr., President The Monarch Cement Company

0251 Anonymous public comment Private Citizen Comment

0252 Anonymous public comment Private Citizen Comment

0253 Anonymous public comment Private Citizen Comment

0254 Lloyd Smith, President Cortech Solutions, Inc.

0255 K. Walser Private Citizen Comment

0256 Anonymous public comment Private Citizen Comment

0258 Anonymous public comment Private Citizen Comment

0259 D. Chambers Private Citizen Comment

0260 B. Alpert Private Citizen Comment

0261 Doug Roark, Vice President of 

Environmental Affairs

GCC America
xiii

Docket No. 

EPA-HQOAR-2011-

0817 Commenter Name Affiliation

0262 Anonymous public comment Private Citizen Comment

0263 C. Mckinney Private Citizen Comment

0264 M. D. Moderacki Private Citizen Comment

0265 M. Rooke Private Citizen Comment

0266 Dr. R. Gorringe Private Citizen Comment

0267 K. Van Dame Private Citizen Comment

0268 B. Dauerty Private Citizen Comment

0269 Dr. M. Ownby Private Citizen Comment

0270 L. Alfson Private Citizen Comment

0271 E. Smeltzer Private Citizen Comment

0272 S. Parsons Private Citizen Comment

0273 W. Handley Private Citizen Comment

0274 J. E. Johnson Private Citizen Comment

0275 J. Smith Private Citizen Comment

0276 R. J. Monteiro Private Citizen Comment

0277 Dr. G. Crouse Private Citizen Comment

0278 J. Fletcher Private Citizen Comment

0279 Dr. J. Chambers Private Citizen Comment

0280 J. Urbanas Private Citizen Comment

0281 R. Hastings Private Citizen Comment

0282 Dr. J. Tullis Private Citizen Comment

0283 D. Harris Private Citizen Comment

0284 B. Pardee Private Citizen Comment

0285 J. Puffinberger Private Citizen Comment

0286 H. Schlaff Private Citizen Comment

0287 E. Wedlock Private Citizen Comment

0288 M. Hadcock Private Citizen Comment

0289 Dr. R. Starr Private Citizen Comment

0290 Dr. G. Degarmo Private Citizen Comment

0291 A. Stonefield Private Citizen Comment

0292 K. Wilson Private Citizen Comment

0293 D. Krull Private Citizen Comment

0294 B. Fitzpatrick Private Citizen Comment

0295 L. Simms Private Citizen Comment
xiv

Docket No. 

EPA-HQOAR-2011-

0817 Commenter Name Affiliation

0296 P. Holmlund Private Citizen Comment

0297 G. Crawford Private Citizen Comment

0298 C. Hinman Private Citizen Comment

0299 E. Robinson Private Citizen Comment

0300 C. Gross Private Citizen Comment

0301 B. Bernstein Private Citizen Comment

0302 M. A. Smale Private Citizen Comment

0303 T. V. Lear Private Citizen Comment

0304 Dr. R. Alexander Private Citizen Comment

0305 R. Weddle Private Citizen Comment

0306 I. Alexakos Private Citizen Comment

0307 T. Hazelleaf Private Citizen Comment

0308 R. Kofler Private Citizen Comment

0309 H. Frank Private Citizen Comment

0310 N. Beck Private Citizen Comment

0311 T. Masanz Private Citizen Comment

0312 J. Black Private Citizen Comment

0313 L. Cox Private Citizen Comment

0314 T. Pretlow Private Citizen Comment

0315 A. Ross Private Citizen Comment

0316 E. Mayer Private Citizen Comment

0317 Holly R. Hart, Assistant to the 

International President, Legislative 

Director 

United Steelworkers (USW)

0318 N. Hemmelstein Private Citizen Comment

0319 D. Luck Private Citizen Comment

0320 Cecile M. Conroy, Director, Legislative 

Affairs

International Brotherhood of 

Boilermakers, Iron Ship Builders, 

Blacksmiths, Forgers & Helpers

0321 C. Crutcher Private Citizen Comment

0322 V. Rogers Private Citizen Comment

0323 M. Pezzati Private Citizen Comment

0324 Dr. J. Spitz Private Citizen Comment

0325 B. Kozik Private Citizen Comment
xv

Docket No. 

EPA-HQOAR-2011-

0817 Commenter Name Affiliation

0326 S. Hathaway Private Citizen Comment

0327 K. Gleeson Private Citizen Comment

0238 R. Hyer Private Citizen Comment

0329 D. Rencher Private Citizen Comment

0330 S. Schmidt Private Citizen Comment

0331 Anonymous public comment Private Citizen Comment

0332 D. Wood Private Citizen Comment

0333 K. Ash Private Citizen Comment

0334 I. Tower Private Citizen Comment

0335 Dr. C. Steinhart Private Citizen Comment

0336 A. Boomershine Private Citizen Comment

0337 Anonymous public comment Private Citizen Comment

0338 B. Santhuff Private Citizen Comment

0339 Anonymous public comment Private Citizen Comment

0340 Anonymous public comment Private Citizen Comment

0341 P. Nielsen Private Citizen Comment

0342 S. Davis Private Citizen Comment

0343 M. Martin Private Citizen Comment

0344 J. Gibson Private Citizen Comment

0345 B. Boone Private Citizen Comment

0346 Anonymous public comment Private Citizen Comment

0347 Anonymous public comment Private Citizen Comment

0348 Anonymous public comment Private Citizen Comment

0349 J. Glasenapp Private Citizen Comment

0350 Anonymous public comment Private Citizen Comment

0351 Anonymous public comment Private Citizen Comment

0352 Anonymous public comment Private Citizen Comment

0353 T. Erichsen Private Citizen Comment

0354 Anonymous public comment Private Citizen Comment

0355 Anonymous public comment Private Citizen Comment

0356 Anonymous public comment Private Citizen Comment

0357 Anonymous public comment Private Citizen Comment

0358 Anonymous public comment Private Citizen Comment
xvi

Docket No. 

EPA-HQOAR-2011-

0817 Commenter Name Affiliation

0359 Anonymous public comment Private Citizen Comment

0360 L. F. J. Gill Private Citizen Comment

0361 Anonymous public comment Private Citizen Comment

0362 J. SmilingCoyote Private Citizen Comment

0363 D. Rawlings Private Citizen Comment

0364 Anonymous public comment Private Citizen Comment

0365 D. Weber Private Citizen Comment

0366 Anonymous public comment Private Citizen Comment

0367 Anonymous public comment Private Citizen Comment

0368 Mass Comment Campaign sponsored by 

Earthjustice (email)

Earth Justice Campaign. The 

comments received are identical in 

content and format. A total of 20,020 

on-time comments have been 

received to date.

0369 D. Sachs Private Citizen Comment

0370 Anonymous public comment Private Citizen Comment

0371 W. Franzen Private Citizen Comment

0372 E. M. Scott Private Citizen Comment

0373 Anonymous public comment Private Citizen Comment

0374 Anonymous public comment Private Citizen Comment

0375 Anonymous public comment Private Citizen Comment

0376 Anonymous public comment Private Citizen Comment

0377 Ben Szafran, Stop Titan Cement.org Private Citizen Comment

0378 Jeff Sama NC Coastal Federation

0379 S. Boekell Private Citizen Comment

0380 T. Ferguson, Ph.D. Private Citizen Comment

0381 Anonymous public comment Private Citizen Comment

0382 Anonymous public comment Private Citizen Comment

0383 M. Erickson Private Citizen Comment

0384 C. Dawson Private Citizen Comment

0385 P. Menyuk Private Citizen Comment

0386 P. Mayer Private Citizen Comment

0387 Cheryl McGraw River Hills POA of Pender, Inc.

0388 Anonymous Public Comment Private Citizen Comment
xvii

Docket No. 

EPA-HQOAR-2011-

0817 Commenter Name Affiliation

0389 M. Harmon Private Citizen Comment

0390 A. R. Warren Private Citizen Comment

0391 J. Ehrlich Private Citizen Comment

0392 S. Bannister Private Citizen Comment

0393 A. Bowen Private Citizen Comment

0394 R. Zucchi Private Citizen Comment

0395 G. Clements Private Citizen Comment

0396 Dr. S. Schrader Private Citizen Comment

0397 J. Tache Private Citizen Comment

0398 A. Berry Private Citizen Comment

0399 B. Winholtz Private Citizen Comment

0400 C. Cicchi Private Citizen Comment

0401 Allie Sheffield, President Penderwatch & Conservancy, et al.

0402 J. Hubbard Private Citizen Comment

0403 M. Bergman Private Citizen Comment

0404 J. Adelfio Private Citizen Comment

0405 K. S. Vargas Private Citizen Comment

0406 G. James Private Citizen Comment

0407 F. Schilling Private Citizen Comment

0408 Dr. H. Corneli Private Citizen Comment

0409 L. Jobe Private Citizen Comment

0410 Dr. M. Bookbinder Private Citizen Comment

0411 C. Nelson Private Citizen Comment

0412 D. Fox Private Citizen Comment

0413 M. Myers Private Citizen Comment

0414 R. W. Houston Private Citizen Comment

0415 W. Ebersberger Private Citizen Comment

0416 P. Gordon Private Citizen Comment

0417 S. G. Campo Private Citizen Comment

0418 A. Weaver Private Citizen Comment

0419 J. Conroy Private Citizen Comment

0420 Dr. J. Munoz Private Citizen Comment

0421 Dr. H. Rice Private Citizen Comment

0422 K. Devries Private Citizen Comment
xviii

Docket No. 

EPA-HQOAR-2011-

0817 Commenter Name Affiliation

0423 J. Beverly Private Citizen Comment

0424 P. Matejcek Private Citizen Comment

0425 J. Boone Private Citizen Comment

0426 J. Bartas Private Citizen Comment

0427 P. Rizzo Private Citizen Comment

0428 Dr. J. R. Leonard Private Citizen Comment

0429 J. Grillo Private Citizen Comment

0430 Ken Derksen, COO Cadence Environmental Energy Inc.

0431 A. Banwart Private Citizen Comment

0432 V. Lepore Private Citizen Comment

0433 N. Lee Private Citizen Comment

0434 Dr. P. Richard-Amato Private Citizen Comment

0435 T. O'Neill Private Citizen Comment

0436 Dr. D. Harrison Private Citizen Comment

0437 S. Brown Private Citizen Comment

0438 K. Shimata Private Citizen Comment

0439 Dr. C. Leman Private Citizen Comment

0440 C. Schmalz Private Citizen Comment

0441 C. O. Dietrich Private Citizen Comment

0442 S. Marett Private Citizen Comment

0443 S. Kuticka Private Citizen Comment

0444 F. Salisbury Private Citizen Comment

0445 J. Steitz Private Citizen Comment

0446 B. Coulson Private Citizen Comment

0447 Dr. L. Young Private Citizen Comment

0448 S. Snypes Private Citizen Comment

0449 K. Rowlett Private Citizen Comment

0450 M. Hannum Private Citizen Comment

0451 L. Durham Private Citizen Comment

0452 V. Kopetz Private Citizen Comment

0453 J. Large Private Citizen Comment

0454 C. Hall Private Citizen Comment

0455 M. Delay Private Citizen Comment

0456 J. Stewart Private Citizen Comment
xix

Docket No. 

EPA-HQOAR-2011-

0817 Commenter Name Affiliation

0457 Dr. W. Amox Private Citizen Comment

0458 J. Newberry Private Citizen Comment

0459 R. Catley Private Citizen Comment

0460 M. Giles Private Citizen Comment

0461 K. Russell Private Citizen Comment

0462 P. Endo Private Citizen Comment

0463 Dr. M. Sowerwine Private Citizen Comment

0464 J. Fails Private Citizen Comment

0465 E. Jung Private Citizen Comment

0466 S. Fieldstein Private Citizen Comment

0467 S. Gilliam Private Citizen Comment

0468 J. Schall Private Citizen Comment

0469 M. Yoder Private Citizen Comment

0470 Mass Comment Campaign sponsored by 

Sierra Club (email)

Sierra Clue Campaign. The 

comments received are identical in 

content and format. A total of 594 

on-time comments have been 

received to date. 

0471 William L. Kovacs, Senior Vice President Environment, Technology & 

Regulatory Affairs, United States 

Chamber of Commerce

0472 Anonymous public comment Private Citizen Comment

0473 Robert A. Garbini, President National Ready Mixed Concrete 

Association (NRMCA)

0474 Vincent J. Brisini, Deputy Secretary, 

Waste, Air, Radiation and Remediation

Pennsylvania Department of 

Environmental Protection (DEP)

0475 Vincent J. Brisini, Deputy Secretary, 

Waste, Air, Radiation and Remediation 

Pennsylvania Department of 

Environmental Protection (DEP)

0476 Daniel B. Nugent, Senior Vice President Buzzi Unicem USA

0477 A. Daniels Private Citizen Comment

0478 William L. Kovacs, Senior Vice President 

Environment, Technology & Regulatory 

Affairs 

U.S. Chamber of Commerce

0479 Anonymous public comment Private Citizen Comment

0480 Anonymous public comment Private Citizen Comment
xx

Docket No. 

EPA-HQOAR-2011-

0817 Commenter Name Affiliation

0481 Sid J. Trant Bradley Arant Boult Cummings on 

behalf of National Cement Company 

of Alabama, Inc. (NCCA)

0482 Timothy L. Matz, Corporate Director of 

Environmental Affairs

Lehigh Hanson on behalf of Lehigh 

Cement Company LLC

0483 Cary Cohrs, Chairman, Manufacturing 

Technical Committee

Portland Cement Association (PCA)

0484 C. Crockett Private Citizen Comment

0485 N. Sharp Private Citizen Comment

0486 Dr. R. Parr Private Citizen Comment

0487 A. Cassebaum Private Citizen Comment

0488 J. Martin Private Citizen Comment

0489 T. McGraw Private Citizen Comment

0490 D. Weber Private Citizen Comment

0491 L. Hansen Private Citizen Comment

0492 L. Devlin Private Citizen Comment

0493 Anonymous public comment Private Citizen Comment

0494 Peter T. Kimmel, Vice President 

Operations

Armstrong Cement and Supply Co.

0495 Robert D. Bessette, President x Armstrong Cement and Supply Co.

0496 Ross Eisenberg, Vice President, Energy 

and Resources Policy 

National Association of 

Manufacturers (NAM)

0497 Dr. M. Merchant Private Citizen Comment

0498 D. Weber Private Citizen Comment

0499 L. Kellams Private Citizen Comment

0500 S. Oehler Private Citizen Comment

0501 J. Gage-Macdonald Private Citizen Comment

0502 J. Rath Private Citizen Comment

0503 T. Peter Ruane, President & Chief 

Executive Officer (CEO)

American Road & Transportation 

Builders Association (ARTBA)

0504 Andrea Geiger, MS Environmental 

Science

Cooper Environmental Services, 

LLC

0505 Andrew T. O‘Hare, Vice President, 

Regulatory Affairs 

Portland Cement Association (PCA)

0506 Melvin E. Keener, Executive Director Coalition for Responsible Waste 

Incineration (CRWI)
xxi

Docket No. 

EPA-HQOAR-2011-

0817 Commenter Name Affiliation

0507 Craig S. Campbell, Vice President, 

Environmental & Government Affairs, 

Cement Division

Lafarge North America, Inc.

0508 James Pew Earthjustice

0509 B. Scott Private Citizen Comment

0510 P. Scheirer Private Citizen Comment

0511 Curtis D. Leslie, Vice President of 

Environmental Affairs

Ash Grove Cement Company

0512 Ali Mirzakhalili, Director, Division of Air 

Quality

Delaware Department of Natural 

Resources & Environmental Control

0513 Zak Covar, Executive Director Texas Commission on Environment 

Quality (TCEQ)

0514 Dr. R. Stallman Private Citizen Comment

0515 R. Kermeen Private Citizen Comment

0516 S. Borrett Private Citizen Comment

0517 Krag Petterson and Douglas Barth Pall Corporation

0518 Jennifer Swearingen Montanans Against Toxic Burning

0519 David Perkins, Vice President, 

Environmental, Government and Public 

Affairs

Texas Industries, Inc. (TXI)

0520 M. Strawn Private Citizen Comment

0521 P. Fry Private Citizen Comment

0522 J. Sorrells Private Citizen Comment

0523 Hector Ybanez, Corporate Environmental 

Manager and Jason Morin, Vice 

President, Environmental and 

Government Affairs

Holcim (US) Inc.

0524 Satish Sheth, Vice President -

Environmental Affairs, US Operations 

CEMEX

0525 Stephen Minick, Vice President of 

Governmental Affairs

Texas Association of Business 

(TAB)

0526 W. J. Hart Private Citizen Comment

0527 C. E. Krause Private Citizen Comment

0528 Dr. R. Guldi Private Citizen Comment

0529 M. Kohn Private Citizen Comment

0530 A. Skari Private Citizen Comment
xxii

Docket No. 

EPA-HQOAR-2011-

0817 Commenter Name Affiliation

0531 P. Erickson Private Citizen Comment

0532 D. Hale Private Citizen Comment

0533 K. Polk Private Citizen Comment

0534 V. Court Private Citizen Comment

0535 The Byte Shop Private Citizen Comment

0536 S. A. Fuqua Private Citizen Comment

0537 T. W. Allgaier Jr. Private Citizen Comment

0538 P. Bradley Private Citizen Comment

0539 L. F. Jamison Private Citizen Comment

0540 E. Gonzalez Private Citizen Comment

0541 G. Hodges Private Citizen Comment

0542 S. Poole Private Citizen Comment

0543 B. Aycock Private Citizen Comment

0544 S. Zann Rosenthal Private Citizen Comment

0545 G. C. Rowley Private Citizen Comment

0546 E. Goulding Private Citizen Comment

0547 A. Robinson Private Citizen Comment

0548 L. Phail Private Citizen Comment

0549 G. Guard Private Citizen Comment

0550 P. Jackson Private Citizen Comment

0551 L. A. Chavez Private Citizen Comment

0552 B. Veals Private Citizen Comment

0553 J. Schmidt Private Citizen Comment

0554 John J. Knotts, Global Sales and 

Engineering Leader, Gas Phase Air 

Pollution Control Technologies Team

W.L. Gore & Associates, Inc.

0555 Mass Comment Campaign sponsoring 

organization unknown (email)

Sponsoring Organization Unknown. 

This is a mass e-mail campaign. The 

comments received are identical in 

content and format. A total of 36 ontime comments have been received to 

date. 
xxiii

Docket No. 

EPA-HQOAR-2011-

0817 Commenter Name Affiliation

0556 Mass Comment Campaign sponsored by 

Sierra Club (email)

Sierra Club Campaign. The 

comments received are identical in 

content and format. A total of 1025 

on-time comments have been 

received to date

0557 Mass Comment Campaign sponsoring 

organization unknown (postcard)

Sponsoring Organization Unknown. 

This is a mass postcard campaign. 

The comments received are identical 

in content and format. A total of 140 

on-time comments have been 

received to date. 

0558 A. and J. Gutman Private Citizen Comment

0559 L. Kain Private Citizen Comment

0560 C. Mitchell Private Citizen Comment

0561 D. Weber Private Citizen Comment

0562 R. Bradley Private Citizen Comment

0563 R. Shew Private Citizen Comment

0564 J. Collins Private Citizen Comment

0565 J. Hunter Private Citizen Comment

0566 J. Van Den Noort Private Citizen Comment

0567 Dr. W. E. Sisson, Jr. Private Citizen Comment

0568 Anonymous public comment Private Citizen Comment

0569 C. J. Paone Private Citizen Comment

0570 Anonymous public comment Private Citizen Comment

0571 S. Kessel Private Citizen Comment

0572 S. Kessel Private Citizen Comment

0573 J. Swearingen Private Citizen Comment

0574 Bruce S. Andersen, Director, Department 

of Air Quality, Public Health Department

Unified Government of Wyandotte 

County, Kansas City, Kansas

0575 P. Neubauer Private Citizen Comment

0576 E. Marum Private Citizen Comment

0577 C. Werre Private Citizen Comment

0578 Faith Chatham, Co-founder DFW Regional Concerned Citizens

0579 S. Woofter Private Citizen Comment

0580 J. Porter Private Citizen Comment

0581 J. Cooper Private Citizen Comment
xxiv

Docket No. 

EPA-HQOAR-2011-

0817 Commenter Name Affiliation

0582 K. and C. Takara Private Citizen Comment

Late comment received November 21, 2012: Curtis Leslie, Ash Grove Cement Company, 

labeled “AG” in this Summary of Comments and Responses document.

A public hearing was held in Arlington, TX on August 16, 2012. A copy of the transcript can be 

found in the docket
1

Section 1: Comments on Regulatory Deadlines and EPA Authority

1.1 One-Year Compliance Deadline Extension

One commenter (0505) stated that the same data and information they discussed in justifying a 

2-year reset of the compliance date likewise repudiates an alternative, 1-year reset of the 

compliance date, which the reconsideration notice also seeks comment. The proposed one-year 

reset alternative is not justified by the facts and would amount to an unreasonable and arbitrary 

decision, as the record clearly demonstrates that at least two years is required. In particular, it is 

not possible for facilities to conduct significant advance work on compliance strategies without 

knowing the standards that will be applicable. Thus, facilities will need to wait until this rule is 

finalized to be able to move forward with the detailed design, planning and optimization of their 

compliance strategies. Thus, a one year reset of the deadline would be insufficient to complete 

the work and the proposed two year reset of the compliance date is warranted. 

One commenter (0505) states that EPA’s assertion that the one-year option might be warranted 

because the industry “is not starting from scratch” and that “there should be on-going planning to 

meet the standards promulgated in 2010 which could shorten the time needed to come into 

compliance with these proposed revised standards (should the EPA adopt them),” is flawed. The 

basic flaw in EPA‘s logic here is demonstrated in EPA‘s closing parenthetical, i.e., “should the 

EPA adopt them.” According to the commenter, it will not and cannot be known until December, 

2012 what EPA‘s final rules may require. Only proposed rules are on the table, and for many 

components of the proposal, EPA‘s preamble requests comment on alternative approaches, even 

affecting the various numeric emission limits (going beyond PM) themselves. As EPA has well 

explained in its preamble, the control strategies companies may employ for controlling the 

various HAPs are highly inter-related. Moreover, EPA has included many new and unanticipated 

components for consideration with its new proposed rule (such as the very complicated coal mill 

provisions and a totally new approach to alternative THC compliance) that present additional 

significant uncertainty to the way the final rule might look. Consequently, companies are now 

very much on hold. They simply will not be able to initiate definitive planning and engineering 

until all these pending uncertainties are resolved and come together in a final rule. 

Commenter 0495 states that rather than considering expanding the compliance timeframe, EPA 

is instead taking comment on shortening the compliance timeframe. The commenter strongly 

opposes setting this type of precedent for MACT compliance. Industry will be hard pressed to 

meet all of the rule’s requirements even with a compliance date at September 2015. Even 

though individual sources could apply for a one-year extension on a case-by-case basis, EPA 

should not rely on that process to provide industry the time it needs to meet the new standards. 

Instead, EPA should provide all of industry with an adequate amount of time to prevent a crush 

of individual facilities seeking a one-year compliance extension.
2

Response: See section V. D of the preamble to the final rule. As noted there, the record supports 

the proposed compliance deadline to September 9, 2015 to meet the amended standards. 

Although a number of companies have in fact begun preparing to meet the standards in advance 

of finalizing amendments (see PCA Comments, App. D), there nonetheless is persuasive 

evidence that determining, bidding, installing, and testing new technology in integrated treatment 

trains will take this additional time. The time estimates provided in the individual company 

survey results are consistent with EPA’s general judgment as time needed to develop and 

implement multi-HAP pollution control technologies. See 77 FR 42386/2.

1.2 Two-Year Compliance Deadline Extension

Several commenters (0481, 0483, 0495, 0505, 0507, 0511, 0519, 0523, 0525) agree with the 

proposed reset of the compliance deadline from September 2013 to September 2015. The 

commenters noted that the re-proposal renders all the standards, other critical aspects of the 

rule, and subsequently compliance strategies, uncertain.

Commenter (0505) stated that there is justification in the record that many existing portland 

cement kilns will require until at least September 2015 to come into compliance with the new 

PM standard and other substantive rule revisions involving THC, Hg, and HCl. A similar 

timeframe is required for the planning, design, construction and implementation for a new or 

reconstructed kiln (and, as currently defined, a coal mill project may also trigger applicable 

standards for a kiln). EPA‘s justification for the need to reset the compliance deadline is set forth 

in the reconsideration notice, at 77 Fed. Reg. 42385-87. The notice expresses EPA‘s recognition 

that the proposed changes to emission standards, in particular to the PM standard and the way 

that all the limits are proposed to apply to sources other than the kiln, will require cement plants 

to assess and develop new control and compliance strategies.

Commenter (0505) stated that in response to a request from EPA to consider the impacts of a 

potential change in the PM limit from the 2010 limit of 0.04 to 0.06-0.08 lb/ton, the commenter 

supplied two documents (attachments to their comments and also in the docket) on which EPA 

relied to justify the reset of the compliance deadline to September 2015: 

• “The “Impact of a Change in the Cement NESHAP PM Limit On Compliance 

Strategies and Schedules” (April 9, 2012), and 

• “Implications of Altered Particulate Matter Limit on PCA Technology Analysis” 

(May 24, 2012). 

The commenter (0505) stated that the April 9, 2012 assessment addressed impacts of a less 

stringent PM limit on 1) the selection and implementation of the most appropriate control 
3

strategy for PM; 2) the effect of the change in the PM limit on the selection of the most 

appropriate control strategy for HCl, mercury, and THC under this rule; and 3) the time needed 

to determine and implement the appropriate control strategies, once a revised PM limit is 

established. The commenter summarized the assessment’s discussion on each of the three areas:

Selection/implementation of PM control strategies. A change in the PM limit from 0.04 to within 

0.06 to 0.08 lbs/ton clinker would provide cement plants with at least one other different control 

option to consider – adding cyclones upstream of an existing ESP or baghouse. This additional 

option would also require additional time to implement, including requiring engineering of the 

ductwork, layout, and associated local permitting.

Selection of the most appropriate control strategy for HCl, mercury, and THC. All of the control 

systems for these three pollutants (with the possible exception of a thermal oxidizer to control 

THC) increase the particulate loading in the exhaust. The options used for controlling HCl, 

mercury, and THC emissions require sources either to collect additional PM injected into the 

exhaust of the unit or consider the indirect impact on the nature and level of the PM to be 

controlled. Because the measures that cement plants use to control HCl, mercury, and THC rely 

on the injection and removal of added particulates, and because a change in the PM limit can 

cause a change in the strategy used for controlling one or more of these pollutants, it is essential 

that compliance with all four standards be coordinated. Specifically, 1) You cannot design these 

injection systems without knowing the ultimate PM limit; 2) The use of these injection strategies 

requires an upgrade in PM control not only to avoid a PM increase but also to manage properly 

the additional particulate materials; 3) Retrofitting of controls in plants with limited space (the 

majority) means that the fans, ductwork, and controls will need to be located and sized carefully 

in a coordinated manner; and 4) These controls require changes to current air permits, and state 

agencies will want to permit the integrated NESHAP compliance strategy rather than want to do 

so piecemeal. 

Commenter (0507) agreed with the EPA that the control strategies companies may employ for 

controlling the various HAPs are highly inter-related. The commenter noted that the EPA has 

included many new and unanticipated components for consideration with its new proposed rule 

that add great new uncertainty to the shape of the final rule, which could mean that the

commenter will need to redo testing done in response to the 2010 rule. The commenter stated 

that cement companies will not be able to initiate definitive planning and engineering until all 

these pending uncertainties are resolved and come together in a final rule.

Cement plants need time to determine and implement the appropriate control strategies, once the 

final NESHAP rule is established. Assuming that the amended NESHAP is finalized in 

December 2012, the earliest that cement plants would be able to commission new engineering 

studies to determine the specific options available to them, and the cost-effectiveness of those 

options, would be December 2012. December 2012 would become the earliest starting date for 

each cement company to initiate their process to conduct new engineering studies, make 
4

decisions regarding the most cost-effective combination of control strategies to implement, bid, 

purchase, build, install the new control equipment, and then test and confirm compliance; which 

obviously would all have to be done before the compliance deadline (footnote: because of the 

limited number of firms qualified to conduct the requisite engineering studies, it is highly 

unlikely that all of the studies that will be required could begin at the same time.)

The commenter (0505) stated that facts and findings that were cited in the April 9, 2012 

document were based on a survey of its membership and reflect almost 100 percent of 

members‘cement manufacturing operations in the United States, i.e., 92 out of the 97 domestic 

kilns in operation are entirely consistent with and supported by findings and conclusions that 

were reached by independent research conducted by EPA which the reconsideration notice cites.

The commenter (0505) stated that the time frame for implementing a new control strategy will 

depend on the particular control measures for all four pollutants and all of the regulated sources 

that, based on the engineering study, is determined to be best. Thus, the amount of time that 

cement plants will need to come into compliance is not cut and dry and will vary from plant to 

plant. The commenter included the following flow diagram to illustrate the time need to prepare 

to comply.

Commenter (0481) provided details of the compliance strategy scheduling issues that will need 

to be addressed before the compliance deadline. The commenter stated that any less time than the 

two-year extension will result in a less efficient, less effective and more costly compliance 
5

strategy.

In their May 24, 2012 document, the commenter (0505) stated that they were responding to an 

EPA request to reconsider its April 9, 2012 analysis and determine whether the conclusions 

would be impacted if EPA elected to propose a PM limit of 0.07 pounds/ton of clinker, with 

compliance demonstrated through a stack test and the use of a continuous parameter monitoring 

system (CPMS), rather than a continuous emission monitoring (CEM) device. The May 24, 2012 

document confirms that the conclusions previously set forth would still be accurate.

According to the commenter (0505), if the loosening of the PM standard allows new alternatives 

to be considered, then the CAA, and EPA‘s regulations regarding its implementation, must 

provide sufficient time for the “process of development and implementation” of those new 

alternatives, along with the implications that those new alternatives have on the best means of 

meeting the other limits of this NESHAP (i.e., THC, HCl, and Hg). To impose a time period that 

does not allow this process to occur would be unreasonable and arbitrary.

The commenter (0505) stated that EPA‘s decision to revise the definition of “kiln” to include 

some coal mill configurations further confounds design considerations for new kilns, thereby 

necessitating the same reset of the compliance date for new or reconstructed kilns.

Commenter (0505) stated that EPA‘s own research, “Engineering and Economic Factors 

Affecting the Installation of Control Technologies for Multipollutant Strategies” (October 

2002), which was cited by EPA at proposal, supports the commenter’s position and is, in itself, 

ample support for the September 2015 compliance deadline. In this completely unrelated 

research regarding the true extent of lead-time that sources require to identify and implement 

the most appropriate control and compliance strategies, EPA found that it is normal for the 

development and implementation of new compliance measures to take as long as 15-27 months, 

or even longer when multiple controls are required, as is the case here. EPA‘s failure to follow 

its own prior research and findings in setting the compliance deadline now would be arbitrary 

and capricious. EPA‘s research fully supports a two-year reset of the compliance deadline rather 

than the shorter period for which the reconsideration notice has also solicited comment. 

Adopting the shorter period would, therefore, be arbitrary and capricious.

The EPA research study uses as its starting point the notion that final rules have been issued that 

require new compliance measures. Here, however, the industry is not even at the starting point 

because the proposed rule, including the limits and the monitoring methodologies, could change 

even further. Once all the limits are established can the regulated community determine the 

proper control technology and begin the development and implementation process. The 

compliance process outlined by EPA‘s research study, which, for the cement NESHAP requires 

multiple controls for multiple pollutants, begins whenever the final rule is ultimately issued. This 

concept applies equally to both new (including reconstructed) and existing sources.
6

One commenter (0505) stated that in December, 2010, Steven W. Miller, the Product Manager 

for Pyroprocessing Technology at FLSmidth, Inc., the leading supplier of heavy equipment to 

the global cement and minerals industries, prepared a declaration that was submitted as an 

exhibit to the U.S. Court of Appeals for District of Columbia to support the motion to expedite 

that PCA had filed in its challenge of the 2010 cement NESHAP final rule. Miller‘s Declaration 

provides further corroboration of the information, findings and conclusions submitted by PCA 

to support and justify the need for a two-year reset. The commenter submitted a copy of the 

Miller Declaration as Appendix C to its comments.

The commenter (0505) stated that Miller‘s Declaration identified and described the following 

thirteen discrete phases of activities that each cement plant will, at a minimum, need to undergo, 

in sequence, in order to comply: (i) baseline testing; (ii) proposal and bid evaluation; (iii) 

permitting; (iv) equipment design and fabrication; (v) layout engineering; (vi) detailed 

engineering (civil, structural and electrical); (vii) shipping; (viii) installation and erection; (ix) tie 

in; (x) commissioning and optimization; (xi) training and updating of site documentation; (xii) 

operation; (xiii) validation testing. Based on Miller‘s experience and knowledge, his Declaration 

projected that the following time-line will be necessary in order to ensure that cement plants will 

be able to fully comply with the NESHAP emission standards for each of the regulated 

pollutants: 

• PM: 19-23 months 

• Hg: 27-31 months 

• HCl: 28-30 months 

• THC: 34-40 months 

One commenter (0505) stated that its members conducted an analysis of their plants in order to 

obtain a generalized assessment of the extent to which they will have to make changes to each 

plant‘s design, emission controls, and other components, in order to comply with the proposed 

revisions to the NESHAP standards. The results of these assessments provide plant-specific 

time-lines of the work and activities that each plant will have to undergo before they will be 

able to achieve compliance with the new standards and implementation requirements now being 

proposed. While the data obtained through these assessment can be considered preliminary 

because the details and requirements of the standards are yet to finalized (and further revisions 

to the standards and requirements are possible as a result of the comments EPA receives), the 

results of these assessments provide ample justification for why the two-year reset is absolutely 

necessary; or conversely why EPA‘s adoption of a one-year alternative reset would be 

unreasonable, inadequate and arbitrary. The results of these plant-specific assessments are 
7

presented in Appendix D to their comments.

One commenter (0519) stated that they need adequate time to design the appropriate controls 

for its existing kilns to meet the new standards when they are finalized by EPA. The commenter 

stated that engineering design is critical to appropriate sizing, production efficiency, energy 

efficiency, sustainable operations, and minimizing maintenance issues, all of which ensure 

proper control of the regulated pollutants. Commenter 0519 stated that design and installation of 

modifications to existing lines, including new controls, requires more time compared to building 

a new system, in order to prevent unnecessary ducting, conveyors, etc. which could conflict 

with other operational equipment and also to ensure proper consideration of the interrelated 

nature of the pollutants. Commenter 0519 stated that integration into current operational 

systems in a way that preserves the operational needs of the facility while also considering the 

overlapping nature of multiple pollutant control requirements requires significant evaluation and 

analysis to design the proper solution. Commenter 0519 emphasized changes to the PM 

standard, will have an impact on design and strategy to control other pollutants under the 

standard and refers to 77 Fed. Reg. 42386. Additionally, Commenter 0519 listed the general 

time schedules for design and installation of new equipment and concluded that the entire 

process will take 32 months. The commenter stated that assuming the rule is finalized in 

December 2012, even the proposed extended deadline leaves little time to allow facilities to 

comply with the revised standards.

Commenter 0519 stated that without the extended compliance facilities will likely be required to 

discontinue kiln operations while controls are installed in order to maintain compliance with the 

standards which will create economic impacts. Additionally the commenter stated that facilities 

will also be unable to meet the requirements of the existing NESHAP testing schedule, which 

does not allow for extensions if a source is not operating. 

One commenter (0525) expressed support for the relevant compliance deadline extension with 

the revised standards, citing PCA’s technical evidence that was submitted separately.

Commenter (0523) stated that there are no off-the-shelf solutions for THC as claimed by the 

2010 rule. The commenter stated that the reset would allow for more time to find solutions for 

controlling THC and/or oHAPs, thus avoiding the negative impact of an RTO.

Commenter (0250) requested that the EPA consider the specific, unique situations of single 

manufacturing facilities when determining the justification for a two year compliance extension. 

The commenter stated that due to the proposed changes in the regulations for the inclusion of an 

In‐line Coal Mill in the definition of “Kiln” and the PM emission limitations, the engineering 

for emission control equipment that is currently in progress, must be re‐evaluated. The 

commenter noted that the mandated modifications affect the time‐tested processes of the 

facility, and with such a limited time to comply with these requirements, the commenter 
8

believes that their facility would be at a competitive disadvantage without the two year 

extension for the following reasons:

1. Rural location with limited resources

2. Less leverage to compete for a limited number of vendors and resources

3. During the construction and process modifications, a lone facility cannot shift 

manufacturing to another facility to sustain short term cash flow, which is more 

critical in today’s long‐term recession with decreased market demand for cement

The commenter concluded that if a two year extension is granted, the process changes and 

environmental controls that are implemented will be more thoroughly engineered prior to 

installation, which will ensure an increase in the efficiency and optimized performance of the 

emission control equipment.

Commenter (0495) states that the EPA proposes to set the compliance deadline for existing 

sources to September 10, 2015. 77 Fed. Reg. 42,370. The commenter supports extending the 

compliance date, but is concerned that this still provides an inadequate amount of time for 

affected sources to meet the new standards. Under no circumstances should EPA reduce the 

amount of the compliance period from that provided in the CAA.

Commenter (0481) stated that the preferred compliance period would be three years, because 

the two year extension requires the commenter’s plant to shut down in August/September, and 

the time period for the commenter’s best commercial interest is in the winter.

Commenter (0512) does not support EPA’s proposal to delay the implementation of this rule, 

and the resulting public health protections, by two years.

Commenter (0518) states that delaying compliance with the 2010 cement rule by two years is 

absolutely unacceptable. The court did not require this extension, and nothing in the proposed 

rule change supports it. On the contrary, EPA’s analysis indicates that a two-year delay would 

cause between 1,920 and 5,000 avoidable deaths. This is simply unjustifiable. 

Response: See section V. D of the preamble to the final rule. We also question the commenter's 

premise that all of the predicted emission reductions and benefits would accrue if the existing 

source CEM-based PM standards took effect in September 2013. As explained at length in 
9

section V.A. of the preamble to the final rule and in other comment responses, PM CEMS would 

not reliably measure the level of the PM standard in many instances. One cannot assume the full 

range of emission reductions (and consequent health benefits) would accrue in the real world if 

the emission measurements themselves are uncertain. Thus, in a meaningful sense, today's 

amendments result in a regime where the required emission reductions will be reliably measured, 

so that the rule's health benefits will reliably occur. 

Three-Year Compliance Deadline Extension

Commenter (0494) suggested a full three year extension to the compliance date, to 

accommodate permitting delays, selection of compliance alternative, engineering, procurement, 

and the monitoring equipment certification process.

Response: See section V. D of the preamble to the final rule.

1.3 Authority to Reset Compliance Date

Regarding the resetting of the compliance date, two commenters (0505, 0519) agree with 

EPA‘s reading of the section 112(i)(A)(3), as well as the Agency‘s reading of NRDC v. EPA, 

489 F.3d 1364, 1373-74 (D.C. Cir. 2007) (NRDC). The commenters stated that EPA is 

amending the standards themselves, as opposed to adjusting ancillary features of the rule, as 

was the case in NRDC. EPA is proposing to fundamentally change the standards. Further, the 

changes in certain standards such as PM dramatically impact other standards and the available 

range of compliance options for those other standards. According to the commenter, section 112 

(i)(3)(A) of the Act requires require compliance “as expeditiously as practicable.” Given the 

significant interrelationship between the emissions of various constituents and the required 

control strategies discussed above, the commenter stated it would not be practicable to require 

compliance any earlier than September 2015.

Two commenters (0475, 0525) stated that the extension of the compliance deadline is clearly 

authorized by the Clean Air Act. The commenter (0525) believes there can be no reasonable 

argument that this schedule does not meet the Clean Air Act Section 112 requirement that 

compliance be achieved as “expeditiously as practicable.”

One commenter (0508) stated EPA proposes to extend the compliance date for existing sources 

by two years would be unlawful and arbitrary. According to the commenter, EPA claims, 

without explanation, that the changes to the PM standard themselves may justify the extension; 

that the new PM standard may be achievable by other, lesser, means although EPA does not say 

which plants would do this or what the changed control strategies might be and; that plants 

could need 15-27 months to design new control measures, although it doesn’t claim to know 
10

what different measures, if any, will be used at which plants. According to the commenter, 

EPA’s proposal to extend the compliance date is unlawful for several reasons. 

First, for the reasons given above, EPA’s proposed changes to the PM standards – on which the 

agency seeks to base its proposed extension of the compliance date – are themselves unlawful 

and arbitrary. Accordingly, basing a compliance date extension on those unlawful changes is also 

unlawful and arbitrary. 

Second, because § 112(d)(7) precludes backsliding, § 112(i)’s compliance date provision must be 

read as precluding compliance date extensions to provide for backsliding. 

Third, EPA ignores the “effective date” limitation in § 112(i)(3)(A) by pretending that it may reset the outside compliance date beyond the 3-year outside date following the effective date of the 

original standard. Moreover, Congress specified the exceptions from this provision, saying 

“except as provided” in the enumerated subparagraphs. For example, § 112(i) provides for caseby-case compliance extensions of up to one year to allow for the installation of controls. When 

Congress enumerates specific exceptions to a statutory scheme, an agency may not create 

additional or different exceptions from the prevailing prescription or proscription. Here that 

means compliance may not be extended beyond the effective date of the original standard. 

Congress did not intend to allow EPA to continually re-set the compliance dates any time it 

subsequently amended the standards. 

Fourth, EPA claims that overall emission reductions will be “roughly the same” as under the 

2010 rule and that “sources will still need to meet essentially the same daily average as they 

would under the 2010 standard.” To the extent EPA is not making significant changes to the PM 

standard but merely adjusting it to reflect a different compliance period – 3-hour stack tests 

rather than 30-day rolling averages – the agency lacks any authority to extend the compliance 

date and the extension violates § 112(i). See NRDC, 489 F.3d at 1373-1373.

The commenter stated that EPA must withdraw its proposed revisions to the cement plant rule 

and allow the 2010 rule to take effect as written.

One commenter (0508) stated that EPA suggestion that PCA’s holding on staying the clinker 

pile requirements supports its extension. To the contrary, that was discussion of staying rules 

that EPA was required to change. It lends no support to delaying compliance with rules that 

EPA seeks to revise as a discretionary matter, a fortiori where those changes are unlawful and 

arbitrary.

One commenter (0508) stated that if EPA promulgated new standards that were more stringent 
11

than existing standards -- i.e., took action that the CAA does allow – it would not extend the 

compliance date for the existing standards; rather it would require compliance with existing 

standards to take place in accordance with § 112(i) and then set new compliance dates for the 

new more stringent standards. Here, extending the compliance date so that some plants might be 

able to do less to control their emissions is egregiously unlawful and arbitrary. Indeed, it is 

irresponsible of EPA to propose to grant a compliance extension that it lacks authority to grant, 

and it would be irresponsible of plant owners or operators to rely on such an unlawful proposal 

to put off the steps they need to take to reach full compliance with the 2010 standards by the 

existing 2013 compliance date. If EPA promulgates the compliance date extension and it is 

vacated or stayed by a court, owners and operators will have only themselves to blame for 

having relied on EPA to take unlawful or arbitrary action on their behalf. 

One commenter (0508) stated that even if EPA could lawfully promulgate some extension to 

the compliance date, EPA does not show that the proposed compliance extension is necessary or 

that it is requiring compliance with the revised standards as expeditiously as possible, as § 

112(i) expressly requires. EPA does not say which plants will change their compliance 

strategies, or that any plants will change their compliance strategies in response to the proposed 

changes to the PM standards. Instead, the agency speculates that proposed .07 standard “may” 

be achievable by means other than a baghouse, implying that some hypothetical plant that may 

have been planning to install a baghouse might now choose to either cancel the installation and 

rely on its existing control equipment or to install less effective controls than it originally 

intended. Because such vague hypothesizing does not show that compliance by 2015 is as 

“expeditious as practicable,” EPA’s proposed extension of the compliance date violates § 

112(i).

One commenter (0508) stated that EPA does not even claim that its proposed 2015 compliance 

date is as expeditious as practicable but, if it did, any such claim would be unsupported by the 

record and therefore arbitrary. EPA argues – again without providing any specifics – that some 

types of change in compliance, which some unidentified plants might or might not undertake, 

could take up to 27 month and that the agency does not want cement plants to have to make 

changes except during winter months. But absent some showing that there are actual plants that 

will make actual changes and need EPA’s proposed extension to do so, the agency’s vague and 

abstract discussion of the amount of time that some types of change might take lends no support 

to the agency’s proposed action. Again, if additional time were needed by specific plants, those 

plants could obtain it lawfully under § 112(i)’s provision for case-by-case extensions, and EPA 

provides no reason to believe that mechanism would not suffice.

Response: EPA has the legal authority to establish the September, 2015 date for the existing 

source stack standards. EPA may extend compliance dates when it amends a section 112 (d) 

MACT standard. This is the thrust of the court’s opinion in NRDC v. EPA, 489 F. 3d at 1373-74 

where the court held that EPA could not extend a compliance date where it amends provisions 

ancillary to the standard, distinguishing the situation where EPA amends the standard itself. The 

court’s discussion of the issue indicates that an extension for an amended standard is legally 
12

permissible, since the court would otherwise have had no reason to allude to and distinguish the 

situation where EPA amends a standard. Section 112 (i)(3)(A) itself does not speak to the case 

where EPA amends a standard before that standard’s compliance date.1 A reasonable way to 

view that situation is that there is a single standard at issue – the amended one – and EPA must 

establish a compliance date for that standard which date is “as expeditiou[s] as practicable”. Any 

other reading would be very problematic as, for example, in the situation where a standard 

proves to be physically unachievable by any source. In this situation, the commenter’s reading 

would still mandate compliance as of the date of the impossible-to-achieve standard. Nor does 

section 112 (d)(7) bar extensions. It is not an anti-backsliding provision (as the commenter 

maintains), but rather is most naturally read as a provision which prevents MACT standards from 

overriding more stringent standards adopted pursuant to some authority other than section 112 

(d).2

 

The commenter’s factual arguments are misplaced. First, it is EPA’s engineering judgment, not 

uninformed speculation, that the amended PM standard affords compliance opportunities for 

existing sources (although not for new sources) which are not available under the 2010 final rule. 

These involve use of a primary PM control device other than a fabric filter with membrane bags, 

different sizing of a primary PM control device, different opportunities for configuring PM 

polishing devices (to capture PM generated in control of HCl, Hg, and non-dioxin organics), and 

different control possibilities for non-dioxin organic HAP by virtue of the amended oHAP 

standard. Second, plant-specific responses (PCA Comments App. D, Docket item EPA-HQOAR- 2011-0817-0505), confirm EPA’s engineering judgment and also provide plant- specific 

information which the commenter claims is lacking. The record further documents the steps 

needed to implement these new control strategies – including engineering studies, technical 

procurement, equipment fabrication and purchase, vendor selection, technology design, 

construction and testing. These processes typically take upwards of 30 months to carry out, 

consistent with both EPA and cement company experience. See 77 FR 42386 /2 and survey 

responses noted above. EPA thus believes that a compliance date of September 9, 2015 

requires compliance with the stack emission standard for existing sources as expeditiously as 

practicable, within the meaning of section 112 (i)(3)(A) of the Act.

Comment: Authority to Change (Weaken) Standard

In comments submitted to respond response to arguments of other commenters based on

section 112 (d)(7,) the commenter (0505, 0507) stated that the most natural and obvious reading 

of CAA § 112(d)(7) is that no Section 112 NESHAP standard can be deemed to override a more 

stringent standard issued under other provisions of the CAA or State law. Second, under the 

reading that section 112 (d)(7) prohibits any weakening of standards, EPA would be precluded 

 1 EPA may, of course, voluntarily amend a MACT standard at any time. PCA v. EPA, 665 F. 3d at 189. 2 Under the commenter’s reading, EPA both could not amend an impossible-to-achieve standard, and could not alter 

that standard’s initially-established compliance date. An example of such an impossible-to-achieve standard, which 

EPA is correcting in these amendments, was the HCl standard of zero (0) during startup and shutdown (which 

standard reflected erroneous information that no chlorine is present during startup and shutdown at cement kilns). 

EPA does not believe that Congress mandated this type of result.
13

from amending a Section 112 standard to make it less stringent even where EPA became

convinced through overwhelming information and data that a standard it had previously issued 

was blatantly unsupportable, which is of course absurd. According to the commenter, the D.C. 

Circuit has consistently ruled that federal agencies have an ongoing duty to assure that their 

rules and policies are updated and revised when it discovers that they are no longer supportable.

According to commenters (0505, 0519), challengers to EPA‘s settlement agreement with PCA 

that underpins this reconsideration of the 2010 final rule have also argued that EPA is barred 

from revising the standards set in the 2010 rule unless EPA finds, in responding to the remand in 

PCA, that its standards must be changed to reflect changed CISWI and cement kiln populations. 

They have further argued that, even if such circumstances exist, EPA cannot now revise the 2010 

standards in a manner which would “weaken” them unless in response to a court order. Even 

assuming their arguments to be correct (and the commenter does not agree that they are correct), 

both of those conditions exist here. Thus, the revisions which EPA is now proposing to make to 

the emission standards set initially in 2010, are changes to the standards which are required 

because EPA arbitrarily included CISWI kilns in its calculations of the limits of the 2010 

standards. Portland Cement Ass’n. v. EPA, 665 F.3d 177, 189 (DC. Cir. 2011) (PCA). As a 

result of the DC Circuit‘s decision in PCA, EPA‘s reconsideration and revision of the 2010 

standards is being done pursuant to the court‘s order. EPA is well within its authority to revise 

now the standards that were improperly set in 2010, as is now demonstrated to be necessary, 

including, as section 112(i)(3)(A) permits, the need to reset the compliance deadline up to three 

years after the new, revised standards become effective.

Response: See preamble section V.A to the final rule and previous response. In addition, the 

commenter is correct that the recalculation of the PM standard after removing CISWI kilns, in 

response to the remand in PCA v. EPA, changed the level of the PM floor and standard. See

EPA Docket item EPA-HQ-OAR-2011-0817-0225 and [the appendices to Final Portland Cement 

Reconsideration Technical Support Document, December 20, 2012 in this rulemaking docket]; 

see also 77 FR 42373/3 (“the existing source floor for PM increased from 0.04 lb ton clinker to 

0.05 lb per ton clinker” (in 30-day average space). For technical reasons, EPA made a further 

change to the standard’s compliance regime so that compliance is based on stack testing rather 

than continuous monitoring with a CEMS. This occasioned a further change in the numerical 

level of the standard (reflecting the difference in testing frequency, determined by the m term in 

the UPL equation). See EPA Docket item EPA-HQ-OAR-2011-0817-0225 and appendices to 

Final Portland Cement Reconsideration Technical Support Document, December 20, 2012 in this 

rulemaking docket. However, the numerical level of the PM standard would change as a result 

of recalculation whether or not expressed as a 30-day average or as a 3 test run average. EPA 

also agrees with the commenter that neither section 112 (d)(7) nor 112 (a)(3) bars EPA amending 

the standard or setting a September, 2015 compliance date for the stack emission standards.

1.4 Extension of Altered Compliance Deadline to All NESHAP Standards
14

Two commenters (0505, 0507) asked for a clarification between the preamble and rule 

language regarding the compliance date extension. One commenter (0505) stated that the 

reconsideration notice states “EPA is proposing that the compliance date for all existing source 

standards including standards for PM, mercury, HCl and THC, clinker piles and the standards 

for startup and shutdown be extended to September 9, 2015.” However, the foregoing 

statements appear to contrast with the regulatory text proposed for §§ 63.1351(c) and (e). 

According to the commenter, § 63.1351(c) can be interpreted to say that standards which are 

not being changed from the 2010 rule may not be subject to the two-year reset. Aside from the 

fact that this was not the intention of the litigation settlement agreement, because of the clear 

inter-relatedness of all of the NESHAP standards, any exclusion of a particular standard and 

related requirements from the two-year reset would be significantly problematic for all of the 

reasons discussed in these comments demonstrating the need for the compliance deadline to be 

uniformly reset two-years. The commenter notes that Section 63.1351(e) states: 

The compliance date for existing and new sources with the requirements for open clinker storage 

piles in §63.1343(c) is [INSERT DATE 180 DAYS AFTER PUBLICATION OF THESE 

AMENDMENTS IN THE FEDERAL REGISTER] or startup, whichever is later. The 

commenter believes that the inclusion of the bracketed text in § 63.1351(e) was in error and does 

not reflect EPA‘s actual intent.

The commenter (0507) suggested that the regulatory language should read:

(c) The compliance date for existing sources is September 10, 2015.

Commenter (0507) suggested that the proposed regulatory language should extend the 

compliance date for all of the new provisions in the September 9, 2010 final rule, not just those 

that are revised in this rulemaking, to avoid confusion.

One commenter (0519) believes that engineering efficiencies, cost efficiencies, and common 

sense all indicate that setting differing deadlines will cause undue complications for both EPA 

as well as the plant operations in demonstrating compliance as well as understanding what is 

needed to maintain compliance. To ensure that the designs and installation of controls are 

completed timely and efficiently, and to ensure that the entire plant operations will maintain 

compliance with the final standards, the commenter believes it is imperative that all of the 

controls be installed at the same time as a part of the entire control strategy addressed 

appropriately during the engineering phase. This ensures that incompatible equipment will not 

inadvertently be installed and cause significant issues with efficiencies, and potentially 

compliance. The commenter supports EPA’s statement that the compliance date for all existing 

source standards including for PM, mercury, HCl and THC, clinker piles and the standards for 

startup and shutdown should be the same, i.e., September 9, 2015.
15

Response: EPA agrees with the commenters that we intended for the extended compliance date 

to apply to the PM, THC, mercury and HCl standards for existing sources for kilns, clinker 

coolers and raw material dryers. However, the September 9, 2015 compliance date does not 

apply to open clinker storage piles.. We have extended the compliance date of that standard to 12 

months to allow time for sources to implement control measures, establish recordkeeping and 

reporting procedures, and to petition EPA to use alternative control measures to those listed in 

the final rule.

Comment: One commenter (0508) stated that even if EPA’s proposed changes to the PM 

standards provided a lawful and non-arbitrary basis for extending the compliance date for those 

standards, they do not support extending the compliance dates for all the other standards. EPA’s 

standards for mercury, THC, and HCl are first-time standards that are not in place at all now, 

even though the CAA required EPA to promulgate them in 1997 and the D.C. Circuit ordered 

EPA to promulgate them in 2000 in National Lime. Delaying compliance with these standards 

now, even though they are not changing, is not just unlawful and arbitrary but an abandonment 

of EPA’s fundamental mission to protect human health and the environment under the authority 

and requirements that Congress established in the CAA. EPA provides no rationale for 

extending the compliance dates for standards other than its PM standard. Instead, the agency 

merely notes in passing that “compliance strategies for the other HAP, all of which involve 

some element of PM control, also may be affected.” That sort of conclusory and self-serving 

speculation is no substitute for reasoned agency decision making. EPA’s failure to provide a 

rationale basis for extending the compliance dates for mercury, HCl and THC adds yet another 

arbitrary aspect to the agency’s action.

Response: EPA disagrees with the commenter that there is no basis for an extension of the 

compliance date for the pollutants other than PM. The PM standard is interrelated with the 

remaining standards in that PM control often is an aspect of control for the remaining standards. 

Thus, the control systems for Hg, HCl, and non-dioxin organics3 increase the particulate loading 

in the exhaust. The options used for controlling HCl, mercury, and THC emissions require 

sources either to collect additional PM injected into the exhaust of the unit or to consider the 

indirect impact on the nature and level of the PM to be controlled. Because the measures that 

cement plants use to control HCl, mercury, and THC rely on the injection, collection and 

removal of added particulates, and because a change in the PM limit can cause a change in the 

strategy used for controlling one or more of these pollutants, compliance strategies for all four 

standards are related and need to be coordinated. In their comments, the industry identified 

specific instances where the change in the PM limit is likely to result in changes to the control 

measures for mercury, THC and HCl. See Final Portland Cement Reconsideration Technical 

Support Document, December 20, 2012 Table 1 (showing estimated savings related to 

alternatives for PM control and PM control associated with capture of mercury and scrubbed 

HCl, and estimating the associated cost savings). Furthermore, as illustrated in the following 

 3 Some thermal oxidizers would not increase particulate loadings, but under the revised standards, EPA does not 

expect sources to use thermal oxidizers for organics control. See section VI.H of the preamble to the final rule. In 

addition, as explained in the text above, the amended alternative organic HAP standard will afford sources 

opportunities to use compliance strategies not involving RTOs.
16

paragraph, changes in the emission limits for organic HAP are also likely both to afford more 

compliance options for organic HAP control requiring time to implement, and also to impact 

controls for mercury. See docket item EPA-HQ-OAR-2011-0817-0505-A5. 

The record includes further specific examples illustrating these points. One facility (kiln A in the 

survey response in App. D to PCA comments) responding to an industry survey of the impacts 

that would result from the revised rule indicated that the revised PM limit would likely result in 

them changing their plans to replace an existing ESP with a new baghouse and instead convert 

the ESP to a baghouse or add a polishing baghouse downstream of the ESP. The facility 

indicated that if, as a result of the PM limit change, they did not replace the ESP with a new 

baghouse, it would impact their plans for installing an RTO for THC control downstream of the 

PM control device. The likely effects include installing the equipment in a different location, 

changing the layout for utilities (natural gas, power, compressed air, and water), new ductwork 

design to tie the main dust collection device outlet to the RTO and the RTO to the main stack, 

and a re-evaluation of the RTO ID fan design capacity. An option to the RTO for THC control 

being considered by the facility was catalytic ceramic filtration (CCF). The same adjustments 

would have to be made for this control option as for the RTO. Because the CCF technology has 

PM removal potential, a decision to install CCF instead of an RTO would impact their strategy 

for PM control possibly negating the need to convert their ESP because the CCF would function 

as a polishing baghouse. Moreover, the source is considering alternatives to a RTO or CCF as a 

result of the amended standard alternative standard for organic HAP. According to the facility, 

an alternative to the RTO or CCF installed upstream of the main dust collection device will 

increase the total volume of kiln gases and would then require a re-evaluation of the inlet 

specifications for any of the PM and mercury control options that were being considered.

For some facilities, the increased PM limit allows them to consider control options that they had 

previously ruled out. For example, one facility (kilns C and D) was planning to replace its ESP 

with a new baghouse. With the PM limit change, they are considering a hybrid ESP conversion 

instead. Their plan to use lime injection for HCl control with its increased PM loading on the 

downstream control was linked to their plan to replace the ESP with a new baghouse. Because of 

the increased PM limit, they can still use lime injection for HCl control despite the increased PM 

loading that will result from its use. As a result of the proposed compliance delay , the facility 

will be able to consider alternative solutions for THC control including SCR, CCF as well as 

other less energy-intense organic HAP specific control technologies. 

EPA also disagrees with industry’s position that the revised definition of kilns to include inline 

coal mills is further justification for the two-year compliance date extension. The end result of 

this provision is that all emissions from kilns meet the NESHAP emission limits for PM, THC, 

mercury and HCl – i.e. no change at all in the kiln emission standards. Essentially all that is 

changing are the means of accounting for meeting those standards when the kiln chooses to 

commingle its emissions with those from the associated coal mill. Emission limits in section 

63.1343 identify emission limits by source, of which the kiln is one. It is true that until now, the 

rule did not provide adequate instruction on how to calculate compliance in the case where a 
17

portion of kiln emissions were diverted to a coal mill or to an alkali bypass, although we 

previously addressed the situation where some kiln emissions were diverted to the alkali bypass. 

Industry understood that all emissions were to be properly accounted for as evidenced by their 

comments to EPA that in the 2010 provisions for the alternative PM limit (63.1343) EPA did not 

account for those situations where exhaust flows from other processes (e.g., coal mills and 

clinker coolers) were commingled with kiln exhaust in the main kiln stack. In this final rule, we 

have provided instructions on determining compliance with the kiln emissions limits for sources 

where a kiln is comprised of an inline alkali bypass and/or coal mill. So while we agree with 

industry that a 2 year extension of the compliance date for existing sources is necessary, we 

reject the argument that the revised definition of kilns to include inline coal mills further justifies 

the extensions. Also, see response to comment 2.2 comment #1 below.

1.5 New Source Applicability Date

Several commenters (0495, 0505, 0507) disagreed with EPA maintaining the definition of new 

sources as those that commenced construction after May 9, 2009. The commenter stated that if 

EPA maintains May 9, 2009 as the new source eligibility date, this will mean that sources 

commencing construction on or after that date will not know until December 2012 to what 

standard they are subject. This is a lag time of more than three and a half years of uncertainty. 

Especially when EPA has proposed major revisions to the rules more than two years after the 

May 9, 2009 date, it is virtually inconceivable that Congress intended such a disruptive result. It 

is clear that within the contemplation of the statute, it was on July 18, 2012 that EPA first 

proposed the standards which are scheduled to become final December 2012. Commenter 0505 

stated that EPA states that it is basing its unwillingness to reset the eligibility date on the 

assumption that the rulemaking record under which the standards were developed was proposed 

on May 6, 2009. But the rulemaking record for the July 18, 2012 proposal is dramatically 

different than the record that existed at the time of the May 9, 2009 proposal. The commenter 

notes that on May 17, 2011, EPA granted reconsideration on many issues associated with its 

final NESHAP and NSPS standards, including the NSPS PM standard for modified sources. 

And with its new proposed standard for PM of July 18, 2012, EPA is dramatically altering the 

basis for the standards, as well as the implementation scheme. Hundreds of new documents 

have been added to the record, many of which relate directly to the issue of the appropriate 

emission limits for all sources (including new sources).

One commenter (0511) stated that the same logic which compels the need for an extension of 

the existing source compliance date also compels an extension of the compliance date for new 

sources. As EPA noted in the preamble, the D.C. Circuit has upheld the idea that EPA may reset 

compliance dates for 112(d) standards if the agency materially amends the standards 

themselves. In the 2012 proposal, EPA makes significant changes to the nature of the regulated 

source, adding a materially changed definition of “kiln” and adding a wholly new definition of 

“coal mill.” The commenter emphasizes that the compliance and compliance monitoring 

requirements related to kiln PM emissions has also significantly changed. In addition, the way 

that THC compliance is calculated has materially changed in that EPA is now revising the rule 
18

to state that for any results below the method detection level, the affected source must assume 

emissions were occurring at the method detection level. This, the commenter states, is contrary 

to established practice as discussed in the 2009 preamble. 74 Fed. Reg. at 21162. The 

commenter goes on to say that the regulation of coal mills at both new and existing sources has 

changed from the 2010 rule. The commenter states that these examples of the significant 

changes proposed to the rule make it difficult for new sources that have begun construction to 

identify and plan for compliance. Assuming that the final rule is signed in December 2012, this 

would require sources that commenced construction after May 6, 2009 and so are already well 

into construction to amend their compliance strategies or simply put the projects on hold until 

greater clarity is available. The commenter believes this would be unfair and would further 

impact the delicate state of the economy. The commenter urges EPA to establish the new source 

compliance date as July 18, 2012 rather than May 6, 2009.

One commenter (0507) noted that the EPA has quite properly “reset” the new source 

applicability date several times since the EPA proposed standards for the Portland cement 

category in 1998.

Response: See section V. E of the final preamble. 
19

Section 2: Comments on Definitions

2.1 Open Clinker Storage Pile Definition

Several commenters (0505, 0507, 0523) stated that the definition is problematic as proposed. 

The commenter (0505) stated that the proposed definition is overly broad and therefore could be 

excessively stringent in practice. The definition needs to be clarified to specify with more 

particularity when an incidental ―pile of clinker will be considered to be a ―storage pile for 

purposes of triggering the regulations applicable to open clinker storage piles. In particular, the 

commenter is concerned that the definition is not limited to any particular quantity of clinker in 

a pile or period of time for the existence of a pile. For example, it is not uncommon for small 

amounts of clinker to be dropped, or fall off a front-loader, onto the ground when being moved 

from a kiln to a storage location or from such a location to the grinding mill. Because these are 

small amounts of clinker, it is also not uncommon that these small quantities of clinker will 

remain where they were dropped and may not be picked up or removed until the necessary 

manpower becomes available; in some cases this could be multiple days. The commenter 

believes that the definition currently being proposed needs to be revised to make clear when a 

pile of clinker will be considered a storage pile for purposes of compliance with the 

requirements of LLL. The commenter proposes the following definition: “Open clinker storage 

pile means an outdoor, unenclosed accumulation of clinker on the ground, which contains in 

excess of 50,000 tons of clinker, and is utilized for a continuous period in excess of 180 days.”

Commenter (0523) stated that the EPA is regulating all clinker piles, regardless of size or 

duration, which creates operational problems with little environmental benefit. The commenter 

discussed the differences between clinker storage piles and clinker stockpiles. The commenter 

noted that because of the short-term duration of temporary clinker stockpiles, the use of work 

practices similar to those proposed for clinker storage piles is not feasible. The commenter 

recommended that the EPA clarify that work practice standards apply only to outdoor (or open) 

clinker storage piles and not to temporary clinker stockpiles.

Commenter (0523) noted that clinker storage in open clinker piles should be defined as any 

clinker placed outside for the purpose of storage prior to being ground into cement. The 

commenter stated that clinker or similar materials that are spilled onto the ground from material 

handling operations such as temporary build up under conveyor belts, material removed from 

equipment to allow access into equipment, or plant clean up materials collected for removal, are 

not open clinker piles. The commenter stated that these potential activities will be defined in the 

facility’s operations and maintenance plan.
20

Commenter (0507) discussed the differences between clinker storage piles and clinker stockpiles, 

and noted that because of the short-term duration of temporary clinker stockpiles, the use of 

work practices similar to those proposed for clinker storage piles is not feasible. The commenter 

recommended that the EPA clarify that work practice standards apply only to outdoor (or open) 

clinker storage piles and not to temporary clinker stockpiles.

Response: See section V. C of the preamble.

2.2 Inline Coal Mill Definition

Two commenters (0505, 0519) expressed concern over the proposed definitions linking kilns 

and in-line coal mills. 

Commenter 0505 stated that by adding a definition of inline coal mill, linking the coal mill

directly to the definition of kiln EPA effectively creates a new affected source under the 

NESHAP not previously subject to regulation. It is commenter‘s view that the New Source 

compliance deadline date for kilns should be July 18, 2012, rather than May 6, 2009.

Commenter 0519 stated that inline coal mills are a complicated issue and that EPA should have 

provided previous notice prior to including them as part of this definition. The commenter 

emphasizes that little or no testing for HAP emissions from these stacks has been done by the 

industry and that the standards were set without the benefit of having measured the emissions 

from these stacks. The commenter believes we cannot anticipate the impact of these emissions, 

and feels that further analysis is necessary in order to properly understand the impact of these 

emissions.

Response: First, EPA rejects the notion that there was inadequate notice of a potential regulation 

addressing accounting for commingled kiln and coal mill emissions. The issue was discussed at 

length in the preamble to the proposed rule, 77 FR 42383-85, and regulatory language proposed

(77 FR 42398, 42399 – 42400, 42402 – 42406, 42408 – 42409). In addition, as we explained in 

our 2011 notice granting reconsideration of certain issues (76 FR 28318, May 17, 2011), the

EPA’s recent amendments to the Standards for Performance for Coal Mills exempted coal mills 

at cement manufacturing facilities whose only heat source was kiln exhaust. See 74 FR 51952, 

October 8, 2009. This change was made in response to comment from PCA which argued that 

coal mills whose only heat source was kiln exhaust were similar to inline raw mills. In the case 

of inline raw mills, we consider the raw mill to be an integral part of the kiln. PCA requested the 

same regulatory treatment for coal mills, and EPA agreed. 
21

Regarding the commenter’s claim that coal mills that are now regulated as an integral part of 

kilns should be considered new affected source whose new source eligibility date is July 18, 

2012, the EPA does not agree. Coal mills that are integral parts of the kiln are considered 

emission points that must be accounted for through various measurement mechanisms, and 

cannot be considered a new source. Thus, this action does not involve new standard setting and 

does not justify setting a revised, new source compliance date.

Regarding the commenter’s concern that EPA lacks test data from coal mills, the final rule 

requires that testing for mercury be done downstream of the coal mill to account for mercury 

from the kiln but to also account for the fact that mercury may be removed in the coal mill. 

Testing for THC and HCl is required upstream of the coal mill so that any HCl and THC that 

would be emitted from the coal is not counted as part of the kiln emissions. However, we are .

also allowing testing either downstream or upstream of the coal mill for all four pollutants. We 

believe that this approach will properly account for kiln emissions with inline coal mills. We 

note that the issue is one of accounting (assuring that coal mills are not used as a means of 

discharging uncaptured HAP emissions from kilns, or not controlling PM from the kiln to 

NESHAP levels ), and does not involve standard setting. Kilns combining emissions with coal 

mill emissions are not subject to different standards than those that do not. Rather, they just 

document compliance in a different manner. Furthermore, the commenter did not provide 

additional data that showed that our approach was not appropriate.

2.3 Raw Material Dryer Definition

Commenter 0505 stated that while it appears that the intent of the revised definition of raw 

material dryer is to exclude dryers used to remove moisture from other than kiln feed, as the 

currently written the new definition would have the opposite effect. For example, the revised 

definition would appear to encompass any piece of equipment used to dry a component of 

feedstock prior to the mixing of all of the components. The commenter believes the revised 

definition is too broad and therefore recommends that EPA retain the definition of raw material 

dryer definition that was adopted in the 2010 final rule.

Response: The intent of the revised definition was to clarify that raw material dryers may be 

used for removing the moisture from materials other than kiln feed. The definition in the final 

rule is the same as proposed.

2.4 Start-up/Shutdown Definition

Commenter (0505) stated that the proposed revisions to Subpart LLL include the adoption of a 

definition for start-up and shutdown but no definitions of startup and shutdown are found in the 

changes being proposed to the regulatory text of 40 CFR 60 Subpart F. The commenter stated 
22

that it is unclear whether EPA intends for the shutdown definitions to apply to both Subpart F 

and Subpart LLL and that it should be clarified to avoid confusion. 

Commenters (0505, 0519, 0523) stated that the definition proposed needs to be revised as it is 

overly simplistic and will create compliance challenges. According to the commenters, 

companies and plants use different definitions for startup and shutdown and do so for a variety 

of operational reasons. 

Some plants use criteria, such as reaching a nominal percentage of normal feed rates, to indicate 

the end of startup. Some plants may use production of clinker rather than initiation of feed to 

signify the end of startup in order to recognize the lag time required for material to move through 

the kiln system. The time required to increase feed to reach normal levels is short for 

contemporary preheater/precalciner kilns and considerably longer for older long kilns. Both 

types of kilns are prevalent throughout the industry. The time between initiating feed and 

reaching normal operating conditions may include some atypical emissions in the calculation of 

30-day averages. 

Site specific definitions have been negotiated with state agencies and then included in a 

company‘s applicable operating permit(s). State or district permits typically have a different 

definition of startup and shutdown, which could ultimately create confusion and conflict on 

interpretation and compliance with these startup and shutdown conditions. Commenter (0519) 

specifically points out, the Texas Commission on Environmental Quality is proposing a new and 

different definition for the Maintenance, Startup and Shutdown permitting that Texas plants will 

be required to address, which need to be reconciled with definitions in the NESHAP to ensure 

that facilities are able to demonstrate and maintain compliance. Commenter (0519) has concerns 

that facilities in Texas will not be able to meet all the differing definitions simultaneously and 

will be out of compliance any time a particular facility is not under normal operations.

According to commenter (0505), combustion may continue for a brief period following cessation 

of kiln feed to assist in moving the remaining material out of the kiln. The ID fan may also 

continue to run to assist in cooling the kiln for up to an additional 36 hours. Additionally, it is 

necessary for the kiln to continue to turn in order to protect the shell and refractory. 

Contrary to what EPA‘s proposed definition assumes, the ID fan is run alone for many legitimate 

maintenance reasons that are entirely unrelated to production. Commenter (0505) stated the 

proposed definition needs to be modified to exclude the starting of the fan during a maintenance 

period when the kiln is not operating. Commenter (0523) suggested a change to the definition of 

startup and shutdown to include the use of the induced draft fan to create a slight draft to vent the 

kiln with fresh ambient air when plant employees are working inside the kiln during a major 

outage. The commenter suggested an alternative definition:
23

“The period of time of kiln operation that does not include normal operations. 

Startup begins when the kiln’s induced fan is turned on and fuel is being 

introduced into the kiln from the discharge end of the kiln.”

Commenter (0505) stated that if EPA adopts a single, uniform, definition of start-up and 

shutdown, they recommend that the following definitions are far more representative and 

reflective of the variety of cement plant operations that currently exist than those definitions 

which EPA has proposed to adopt: 

• Start-up period Commences: when both the ID fan draft is running and fuel 

combustion is present in the main burner of the kiln. 

• Startup period Ends: when feed has been fed continuously to the kiln for a period of 

at least 120 minutes OR when the kiln feed rate exceeds 60 percent of the kiln design 

limitation rate. 

• Shutdown period Commences: when the kiln feeder is shut off.

• Shutdown period Ends when continuous kiln rotation ceases.

Start-up fuel is used only in the main burners. Also, auxiliary burners may be utilized to cure or 

prepare new refractory brick. These activities are – and should therefore be classified by EPA to 

be – maintenance activities rather than start-up activities.

Commenter (0505) stated that EPA‘s proposed definition and the preamble‘s discussion seem 

to be directed at startup after extended outages (e.g. annual maintenance outage, inventory 

outage or other ―cold start-ups). However, in the cement industry, startup occurs far more 

routinely and frequently when feed is stopped for a “kiln trip.” This is the period of time that 

occurs while the kiln is banked hot, rotated slowly, and the effluent flow rate drops to a small 

fraction of normal levels. EPA‘s definition of startup needs to reflect this circumstance. Actual 

emission rates and emission concentrations can be variable/different during such kiln trips as 

compared to levels occurring during normal operation. Thus, the emission monitoring data 

obtained during such periods is not likely to be reliable for purposes of determining actual 

compliance. 

One commenter (0508) stated that EPA’s proposed change to the definition of “startup” to 

mean until “continuous raw material feed is introduced” suggests that plants can introduce raw 

materials into the kiln during “startup” or “shutdown” mode so long as they do not introduce it 
24

“continuously.” Allowing sources to introduce raw materials into the kiln during startup and 

shutdown at all is inconsistent with the concept of startup and shutdown, and is, effectively, a 

loophole that allows plants to operate their kilns and produce cement without meeting the 

relevant emission standards. EPA does not provide any explanation for allowing plants to avoid 

compliance with normal emission standards when they are introducing any raw materials into 

the kiln at all.

Commenter (0523) agreed that kiln start-up concludes once kiln feed is being fed continuously 

into the kiln. The commenter noted, however, that “continuously” can be defined when the kiln 

feed rate exceeds 50% of the kiln’s nominal rate for more than 15 minutes.

Response: After reviewing the comments, EPA agrees that an ID fan can be operated for 

maintenance during periods other than startup. In order to account for the maintenance activities 

where the ID fan is operational, the definition of start-up /shutdown will be revised from 

proposal so that start-up commences when both the ID fan draft is running and fuel combustion 

is occurring in the main burner of the kiln. When feed is introduced into the kiln, HAP emissions 

will be immediately released as the feed heats up moving down the kiln. No emissions data were 

provided by the commenters to the contrary. Therefore, the definition retains the condition that 

the kiln is in startup mode until feed is continuously fed to the kiln. 

We also disagree that it is necessary to revise the definition to account for the “kiln trip” as 

suggested by one commenter. While the commenter’s claim that emissions may be more variable 

or different during kiln trips as compared to during normal operations, we believe it is likely that 

emissions will be less than normal because feed is not continuously being introduced into the 

kiln at a rate less than full operation mode..

Regarding the comment that the subpart LLL definition of startup and shutdown may conflict 

with some state definitions and lead to confusion and problems with compliance, state 

regulations cannot override federal regulation but can be more stringent. To the extent that a state 

regulation is defining startup and shutdown for the same reason, the definition must be consistent 

with subpart LLL. If the state definition is being used for other purposes, it may be appropriate 

that the state definition and subpart LLL definition are not identical.

We disagree with the commenter 0508’s claim that the rule can be circumvented and that cement 

plants will be able to manufacture cement using other than continuous feed to the kiln. The 

production of clinker requires steady-state conditions in the kiln which are dependent on an 

optimum mass of feed material in the kiln. The kiln operator would not be able to attain the 

necessary steady-state temperatures to produce quality clinker without proper loading of the kiln. 

Nor is it reasonable to think that operating a kiln for the production of clinker is economically 

viable without continuous feed to the kiln.
25

In the event that feed to the kiln is halted for some operational reason, the kiln is now in 

shutdown mode and is subject to the work practice standards for startup and shutdown. Even 

though feed to the kiln has stopped, there will still be residual feed in the kiln that may emit 

some HAP. As we said at proposal, any emissions that do occur during a startup or shutdown are 

likely to be much lower than during normal operation as a result of the presence of little or no 

feed in the kiln during the shutdown. For these reasons the final definition of startup and 

shutdown retains the condition that startup ends with the introduction of continuous feed for at 

least 120 minutes or when the feed rate exceeds 60 percent of the kiln design limitation rate, 

whichever occurs first.

2.5 Kiln Operation Definition

Commenter (0505 - Appendix G) recommended that EPA ensure that the definitions for 

“operating day” and “startup and shutdown” are consistent.

Response: After reviewing the definitions, we believe that the two definitions are consistent. 
26

Section 3: Comments on Emission Standards/Limits

3.1 Particulate Matter (PM): General Support and Opposition for the Standard 

Several commenters (0475, 0494, 0505, 0507 0525) stated that they support the revisions EPA 

has proposed to make to the PM standard for new and existing sources under both NESHAP and 

NSPS. 

Commenter (0507) stated that although the proposed stack testing-based PM emission 

standards are more stringent than those proposed in 2009, the commenter is not opposed to the 

proposed standards, and acknowledged that they allow cement companies greater flexibility. 

Commenter (0495) supports EPA’s approach that allows modified sources to comply with 

existing source NESHAP rather than NSPS. 

Response: EPA acknowledges the commenters’ general support of the amended PM standard.

3.2 PM: Clarification on Stack Test to be used

Commenter (0494) stated that if the EPA retains the requirement to demonstrate ongoing 

compliance by meeting an operational limit, the EPA should clarify in the rule that the 

operational limit need not be based on the most recent stack test. The commenter stated that in 

§63.1349(b)(1)(i)(C), the reference to "verify an existing ... operating limit" may address this 

concern. 

Response:. The EPA disagrees with the commenter and the final rule requires that the operating 

limit be reassessed and adjusted at least annually following the PM performance test. The EPA 

recognizes that the relationship of PM concentration to PM CPMS response may change based 

on the physical characteristics of the PM itself and, as such, it is appropriate to modify the 

operating limit to align with the most recent assessment of this relationship (i.e. the most recent 

performance test data).
27

3.3 PM: UPL Calculation Method Under-predicts Variability

Commenter (0523) discussed the collection of PM emissions data that was submitted to the 

EPA as part of a Petition for Reconsideration. The commenter noted that the EPA did not 

consider the data. The commenter responded that the petition was an example of real continuous 

variability; therefore, it should not matter if the source was classified as a LLL, EEE, or CISWI 

kiln. The commenter continued that the submittal was about the evidence that the variability 

calculation methodology used by the Agency was not accurate when applied to real data 

regardless of the regulatory classification of the source. The commenter stated that the data 

collected from PM CEMs demonstrated that the formula EPA used to predict variability and 

rolling averages for the PM standards in the Rule dramatically underestimated variability and 

resulted in inaccurate predictions.

Commenter (0523) presented concerns about the calculation of the proposed PM MACT floor. 

The commenter stated: 

“The final value predicted by the UPL formula used in the current proposed rule is fairly 

close because the second term (1/n + 1/m) in the UPL equation produces minimal 

deterioration of the measured variability since m=3. However, the UPL approach still has 

issues when EPA attempts to stretch it beyond its limitations. For example, if EPA were 

to convert the proposed PM limit to a 30-day rolling average, the measured variability 

would be reduced by more than 50% by the second term in the UPL equation. It is this 

reduction or damping of the second term that causes the UPL to underestimate when it is 

used to change from one sampling frequency to another. In Figure 1, the damping effect 

of the second term is graphically shown for the 28 PM floor kilns. According to the UPL, 

so long as the four kilns have at least six stack tests (i.e., 24 observations) the measured 

variability of the stack tests would be reduced by more than 50% when converted to a 30-

day rolling average. Clearly, this does not occur in reality. In reality, the variability 

increases from a three-hour observation to a 24-hour observation. Additionally, EPA has 

not considered source-to-source variability nor within plant variability. In the 2010, 

Holcim and PCA submitted detailed statistical analysis to show that long-term variability 

could be predicted from 30 to 40 data points as long as the data was collected over a long 

period of time (i.e., one year). Furthermore, the second term behaves in the same way for 

any pollutant and some pollutants have more variation than others. These are examples of 

why the UPL has limitations and EPA needs to be aware of them and use the UPL with 

caution and limits.” [The commenter] “recommends that EPA forgo using the UPL to 

predict limits with different sampling frequencies.”

The commenter provided a figure showing the damping effect of the second term. [page 5 

Figure 1].
28

Response: EPA reiterates its position at proposal as to these data: “because the EPA is 

proposing to no longer use a CEMS-based regime for the PM standard, the Holcim information 

[i.e., the CEMS data from 4 of their kilns] is no longer of direct relevance in setting the level of 

the PM standard. A further issue with the data is that they were not obtained using CEMS 

calibrated according to PS–11, the protocol specified in the rule. Accordingly, the EPA is not 

basing its proposal of a revised PM standard on these data.” 77 FR 42374 n. 3. The data also 

come from solid waste incinerator kilns, hazardous waste incinerator kilns, and non-best 

performing cement kilns, so the relevance of the data in setting PM standards is uncertain in any 

case. The commenter offered no quantified explanation in either its comments or its petition. 

explaining how the data were a valid predictor of best performing cement kilns’ variability in 

PM control. See Sierra Club v. EPA, 479 F. 3d at 882 (D.C. Cir. 2007) (there must be a 

demonstrated relationship between performance of non-best and best performers before data 

from non-best performers can be used as a predictor of best performers’ variability). 

The commenter also addresses issues related to the UPL equation, which is a predictor of source 

variability. 75 FR at 54974-75. EPA did not reopen this issue in this rulemaking. Rather , EPA 

recalculated floors after removing CISWI kilns from the 2010 and changed the compliance 

regime to be based on stack tests rather than CEMS. EPA did not reopen the issue of floor 

setting methodology, calculation of variability, or data to be used in establishing the standard. 

These issues were resolved in the 2010 final rule. In addition, the issue of application of the 

UPL to the PM standard was litigated and resolved in favor of EPA in PCA v. EPA . 665 F. 3d 

at 189. Since EPA did not reopen the issue, EPA is not addressing these comments. 

3.4 PM: Exemption from Operating Surrogate Limit for BACT and CAM CEMS 

Units

Commenter (0523) supported the proposed rule’s approach to calculating an operating limit, 

but noted that other environmental agencies might require a PM CEM to comply with BACT 

and/or CAM programs. The commenter discussed how different requirements could result in 

compliance under one program but possible non-compliance under another. The commenter 

suggested that the EPA exclude sources from developing and complying with an “operating 

surrogate limit” under NESHAP beyond the stack testing requirement if it has to comply with 

BACT or CAM limits using a PM CEM.

Response: A source can petition the Agency under section 63.8(f) to approve the use of a PM 

CEMS as an alternative compliance monitoring method provided the criteria of that provision are 

satisfied. Sources applying for an alternative compliance monitoring method using PM CEMS 

would need to address and resolve for the source all PS 11 issues as part of their application 

process. Also, the subpart LLL standard for PM could not be changed. EPA notes that the 

subpart LLL limit is not a 30-day average but is short-term stack test using EPA Method 5 

consisting of three separate runs of a minimum sample volume. 
29

3.5 PM: Standard should not Apply to Modifications Made to an Existing Kiln 

and or Cooler

Commenter 0505 does not agree that the PM standards should also apply to modifications 

made to an existing kiln and or cooler for NESHAP purposes, as the proposed language of § 

63.1343(b)(1) clearly directs. Unlike § 111(a) of the Clean Air Act, 42 U.S.C. 7411(a), which 

defines new source to apply to the construction or modification of a stationary source, § 112 

does not. Section 112 is the section of the Clean Air Act that applies here, not § 111. Section 

112, 42 U.S.C. 7412, defines new source to apply solely to the construction or reconstruction of 

a stationary source and defines modification separately, thereby signifying that reconstruction 

and modification are not intended to be the same thing.

Response: As we stated at proposal, “under the September 2010 final NESHAP, existing kilns 

and clinker coolers are subject to the PM limit of 0.04 lb/ton clinker. If the kiln or clinker cooler 

undergoes modification, it would continue to be subject to 0.04 lb/ton limit, but would now be 

subject as well to the NSPS limit of 0.01 lb/ton clinker as a modified kiln. Notwithstanding that 

there are independent justifications under section 111 that could justify this result (see PCA v. 

EPA, 665 F 3d at 190–91), the EPA believes that it is more appropriate for modified kilns and 

clinker coolers to meet the NESHAP PM limit for existing sources. Therefore, the final rule 

specifies that existing kilns and clinker coolers that are subject to the NESHAP existing source 

emissions limit would continue to be subject to that limit and not to the more stringent limit for 

new sources under the NSPS.” 77 FR 42385. Thus, a modified kiln would be subject to the 

existing source limit of .07 lb/ton clinker. The commenter is correct that EPA incorporated this 

new source performance standard in the NESHAP provisions in proposed section 63.1343 (b)(1) 

(in the text preceding the table). This seems to EPA to be a legitimate way of drafting the 

provision. .

3.6 PM: Standard should not be Changed Until CISWI Rule is Finalized

Commenter (0518) states that EPA has recalculated and nearly doubled the emission limit for 

PM (from 0.04 to 0.07 lb/ton of clinker), after eliminating all data from kilns it presumes to be 

solid waste incinerators (or CISWI kilns). Yet, without EPA’s final rule on the definition of 

solid waste, there is absolutely no way to determine which kilns will remain CISWI kilns and 

which will be redefined as conventional kilns, since many wastes are slated to be redefined as 

“alternative fuels.” Therefore, EPA’s analysis supporting this proposed emission rate change is 

not valid. No changes to the NESHAP or the NSPS should be made before EPA has issued its 

final rule. 

Response: EPA based its determination of which kilns were CISWI on the NHSM rule as 

promulgated. See 76 FR 28322 (May 17, 2011) and 77 FR 42372. As noted in the preamble to 

the final rule, there was disagreement with EPA’s analysis with respect to only one kiln where 

commenters showed convincingly that the kiln was indeed a cement kiln under the NHSM rule. 
30

(See comment 3.19 below.) At the time of proposal, EPA also evaluated its analysis against the 

proposed clarifications to the NHSM rule being considered as part of the reconsideration process, 

and determined that none of these potential clarifications would affect EPA’s count of CISWI 

kilns. See “Consideration of Proposed Clarifications to NHSM Rule, January 25, 2012”, memo 

to Docket EPA-HQ-OAR-2011-0817. The reconsideration process for the NHSM rule has now 

concluded and EPA finds that the clarified NHSM rule, after reconsideration, does not have any 

effect on the count of CISWI kilns used in the reanalysis in the portland cement NESHAP. 

Comment: PM: Weakening of PM Standard is Unlawful

One commenter (0508) stated that weakening the PM standards would be unlawful. EPA does 

not claim to make this change in response to the remand in PCA, and the record makes clear 

that merely removing the waste-burning kilns from the agency’s floor analysis would not result 

in these changes. Instead, these changes result from EPA’s entirely voluntary decision to change 

the way in which compliance with the PM standard would be monitored. Without notifying or 

engaging the public, EPA came to agree with industry that conducting an audit of the PM 

CEMS in accordance with Performance Specification (PS) 11 could be problematic. Rather than 

attempting to solve these problems, EPA agreed with industry – again without providing any 

opportunity for public input – to propose different PM standards based on a different 

compliance method. Further, EPA elected to enter into an unnecessary post-decision 

“settlement” with industry which required the agency to make these changes within months. 

The agency now advances this elective settlement and schedule as an excuse for failing to 

address the alleged PM CEMS issues and, instead, simply abandon using PM CEMS for 

compliance.

Commenter 0508 stated that the specific changes EPA proposes – from .04 to .07 for existing 

sources and from .01 to .02 for new sources – is driven not by the agency’s response to the PCA 

decision but by its voluntary abandonment of the PM CEMS requirements. To the extent EPA’s 

proposed standards would diminish or replace more stringent standards in the existing rules, they 

are not consistent with 112(d)(7) and are, therefore, unlawful.

Indeed, the D.C. Circuit has already addressed a similar attempt by EPA to avoid plain statutory 

limits on its authority by claiming some extra-textual authority to correct errors. In New Jersey v. 

EPA, it squarely rejected EPA’s claim that it could delist power plants without satisfying the 

requirements of § 112(c)(9), 42 U.S.C. § 7412(c)(9), just by claiming that it was correcting its 

original decision to list them.

Response: As explained in section V. A of the preamble, EPA does not accept the commenter’s 

(strained) reading that section 112 (d)(7) must be read as an anti-backsliding provision. 
31

3.7 PM: Abandonment of PM CEMS Due to PS-11 Issues is Unlawful

One commenter (0508) stated that EPA’s own description of the alleged problems in using PM 

CEMS and PS 11 reveal that the changes to the proposed different PM standards based on a 

different compliance method are unnecessary. First, EPA admits that PS 11 is relevant to only 

some PM CEMS. The agency does not dispute that cement plants could use other types of PM 

CEMS for which any issues relating to PS 11 would be irrelevant. 

Second, EPA admits that “one can improve the method detection capabilities of the Method 5 or 

other filterable PM test method by increasing sampling volume and run time.”

EPA also states that PS 11 correlation calculations would have to “account for any PM CEMS 

measurement uncertainty,” but provides no reason that this would not be possible. 

EPA claims that because cement plants’ particles vary in size and other characteristics, PS 11 

correlations developed for one set of conditions may not apply to other conditions although EPA 

admits that some plants are already using CEMS for which this is not even an issue. 

EPA’s claim that its rule is not currently predicated on CEMS that can be correlated to PS 11 

regardless of variations in particle size is irrelevant. EPA is proposing to make significant 

changes in the way compliance with PM standards is demonstrated. Given that, the agency has 

no reason to rule out consideration of different PM CEMS. EPA speculates that predicating 

standards on a different type of CEMS “is likely to take several years.” EPA provides absolutely 

no explanation or record support for that speculation, however. Moreover, the agency’s refusal to 

consider other technologies for this purpose even though they are already in use at some plants is 

directly at odds with its willingness to let plants demonstrate compliance with the hydrogen 

chloride standards through the use of CEMS for SO2, even though it “had no data that 

demonstrated a direct link between HCl emissions and SO emissions.”

Even if it were not possible to use other PM CEMS, EPA further admits that “PS 11 provides for 

means to minimize the effects of changing particle sizes.” The agency states that it did not even 

“consider such an approach,” however. EPA states that technical work is needed to determine if 

this approach would work, but apparently did not even attempt to undertake this work.

Finally, EPA does not say why it is necessary to use PS 11 to audit PM CEMS. The agency does 

not deny that other performance specifications are available and, indeed, already in use in the 

United Kingdom. 

Response: The commenter is mistaken in stating that PS 11 only applies to some PM CEMS. 

For every installation of a PM CEMS where the instrumentation must demonstrate compliance 

with an emission limit, no matter the source category, the rule requires that instrumentation be 

certified pursuant to PS 11 . Extending the duration of the method 5 stack test gives this 

reference method additional opportunity to collect more sample mass, but this is no guarantee 

that the time added to the test will collect enough particulate mass to resolve detection issues, 
32

especially when testing is conducted at the better performing (lower emitting) sources. While 

compliance with a PM emissions limit is demonstrated with a Method 5 test result below the 

method detection limit which is also below the emissions limit, correlation with a PM CEMS is 

not resolved with this same presumption due to the higher level of uncertainty in the measured 

result. Additionally, longer test runs inherently increase the variability of the PM CEMS data 

collected during the test, which may cause further difficulties with the correlation between 

instrument and reference method.

The EPA maintains that special problems are posed by the size and variability of cement kilngenerated particulate. The EPA also maintains that the standard light-scintillation type of PM 

CEMS would likely encounter higher variability for the same PM concentration, and have 

difficulty satisfying correlation protocols as a result. The EPA holds that beta gauge CEMS 

could potentially resolve at least some issues related to cement particle variability but also 

maintains further that these devices are largely untested in the cement industry, and none (so far 

as the EPA is aware) has successfully completed a PS 11 certification, meaning that none are 

currently capable of providing compliance grade emissions data.

The mere existence of beta gauge CEMS does not resolve all questions as to their reliability in 

the cement industry. The EPA reiterates, as it did at proposal, that there needs to be some 

assurance of the reliability of that methodology to certify with PS 11 at low levels (as required 

by this final rule). That information does not presently exist. Relative to Portland cement 

sources, it would be speculative to assume that beta gauge CEMS would successfully pass a PS 

11 certification to reliably and quantifiably measure compliance with the NESHAP at all 

installations. The EPA cannot promulgate a rule wherein the compliance determination is 

predicated upon the presumptive success of an unproven technology.

The commenter further maintains that rather than amend the standard to change the compliance 

test methodology and averaging time, the EPA should revise PS 11 instead, evidently assuming 

that a revision can be done rapidly. The commenter’s assumption is mistaken. Performance 

specification development is a process that takes multiple years and involves data collection on 

types of technologies, field testing, comparison to reference measurement methodology, 

workgroup and stakeholder meetings, peer review, rule proposal and public comment period, as 

well as comment response and final promulgation of the Performance Specification. Performance 

Specification 11, at issue here, was over 3 years in development, from concept to final 

promulgation, and involved a budget of $250,000. Based on this past history, it is likely to result 

in a delay of 3 years or more were the EPA to delay promulgation of this final rule until we could 

undertake the process to research, propose and finalize solutions to PS-11 that may ameliorate 

some of the issues now present. Furthermore, such a process would not address the issues 

relating to measurement uncertainties using Method 5 at low PM concentration levels near its 

detection limit, and so there would remain significant technological hurdles to clear before the 

EPA could require the use of PM CEMS in respect to this final rule. 

With regard to the use of PM CEMS in European installations the EPA acknowledges the use of 

this instrumentation and would point out to the commenter that the European calibration and 

certification of this instrumentation is completely different than in the United States with our PS11 requirements. European monitors are certified in a laboratory environment, and calibrated on 
33

site by the instrument vendor when installed. CEMS installations in the US must meet more 

rigorous Performance Specification certification through a series of comparisons to reference 

measurements conducted on the stack and involving the flue gas matrix at the facility. The two 

certification regimes differ greatly in approach and simply adapting European standards to US 

facilities does nothing to mitigate the difference or improve instrument measurement reliability.

3.8 PM: Utilization of the UPL Method is Unlawful and does not Account for 

Operator Efforts

3.8, Comment #1: One commenter (0508) stated that the revised PM standards also would 

violate §112(d)(3) and binding D.C. Circuit precedent. Because Clean Air Act § 112 

unambiguously requires EPA to set floors reflecting the “average” emission level achieved by 

the best sources, setting floors that instead reflect a UPL for those sources is unlawful. By 

insisting that it can set floors at this level, EPA deprives the word “average” of meaning and 

substitutes its own policy preferences for Congress’s plainly expressed intent. See New York v. 

EPA, 443 F.3d 880, 885 (D.C. Cir. 2006) (“courts must give effect to each word of a statute”); 

New Jersey v. EPA, 517 F.3d 574, 582 (D.C. Cir. 2008) (rejecting statutory reading that 

“substitutes EPA’s desires for the plain text” of the statute”)

By claiming that it can use the UPL for all sources in the top twelve percent, EPA also misreads 

its authority to consider variability under the Clean Air Act and relevant caselaw. Although EPA 

may consider variability in estimating an individual source’s actual performance over time, 

nothing in the Act or the caselaw even suggests that the agency may account for differences in 

performance between sources except as § 129 provides, by averaging the emission levels 

achieved by the sources in the top twelve percent. Indeed, EPA errs by viewing the different 

emission levels achieved by different sources as “variability” at all. The different emission levels 

achieved by different sources are just differences in performance and provide no basis for 

applying statistical methods.

Commenter 0508 also stated that EPA also fails to explain its assumption that sources’ actual 

emission levels will vary to the full extent of the 99th percent UPL. By its nature, a UPL predicts 

sources’ variability in performance based on characteristics of the data already available for 

them, the number of data points, the median of the data points, and the standard deviation. The 

UPL does not consider an operator’s efforts to limit variability in emissions – or at least upward 

variability – by maintaining and operating the source carefully to control emissions. Yet, as both 

EPA and the D.C. Circuit have recognized, operator training and care and source maintenance do 

operate to control emissions. By using the UPL, EPA ignores the effect of operator training and 

care and source maintenance on emission levels. Doing so is just as unlawful and arbitrary as 

setting floors that ignore the effects of cleaner fuel use; it results in floors that do not reflect the 

best sources’ actual performance.

Commenter 0508 stated that the agency has not set the new source floor at the emission achieved 

in practice but rather the 99 percent UPL. Although it may be permissible to set new unit floors 

“at a level that reasonably estimates the performance of the ‘best controlled similar unit’ under 

the worst reasonably foreseeable circumstances,’” CKRC, 255 F.3d at 863 (quoting Sierra Club, 

167 F.3d at 665), the UPL is not an estimate of what the single best unit actually “achieved in 

practice” under any circumstances. By definition, it is a “prediction” of the level EPA expects all 
34

future tests by that unit to fall below. 42 U.S.C. § 7429(a)(2); Sierra Club, 479 F.3d at 880.

Response: EPA did not propose nor request comments regarding the utilization of the UPL. 

Since EPA did not repropose, reexamine, or otherwise reconsider this issue, EPA is not 

addressing these comments here. EPA also notes that the applicability of the UPL to the PM 

standard was litigated and resolved in EPA’s favor in the PCA v. EPA litigation. 665 F. 3d at 

189.

Comment: PM: Utilization of the UPL Method is Unlawful and does not Account for Operator 

Efforts

One commenter (0508) stated that the revised PM standards also would violate § 112(d)(3) and 

binding D.C. Circuit precedent. Because Clean Air Act § 112 unambiguously requires EPA to 

set floors reflecting the “average” emission level achieved by the best sources, setting floors 

that instead reflect a UPL for those sources is unlawful. By insisting that it can set floors at this 

level, EPA deprives the word “average” of meaning and substitutes its own policy preferences 

for Congress’s plainly expressed intent. See New York v. EPA, 443 F.3d 880, 885 (D.C. Cir. 

2006) (“courts must give effect to each word of a statute”); New Jersey v. EPA, 517 F.3d 574, 

582 (D.C. Cir. 2008) (rejecting statutory reading that “substitutes EPA’s desires for the plain 

text” of the statute”)

By claiming that it can use the UPL for all sources in the top twelve percent, EPA also misreads 

its authority to consider variability under the Clean Air Act and relevant caselaw. Although EPA 

may consider variability in estimating an individual source’s actual performance over time, 

nothing in the Act or the caselaw even suggests that the agency may account for differences in 

performance between sources except as § 129 provides, by averaging the emission levels 

achieved by the sources in the top twelve percent. Indeed, EPA errs by viewing the different 

emission levels achieved by different sources as “variability” at all. The different emission levels 

achieved by different sources are just differences in performance and provide no basis for 

applying statistical methods.

Commenter 0508 also stated that EPA also fails to explain its assumption that sources’ actual 

emission levels will vary to the full extent of the 99th percent UPL. By its nature, a UPL predicts 

sources’ variability in performance based on characteristics of the data already available for 

them, the number of data points, the median of the data points, and the standard deviation. The 

UPL does not consider an operator’s efforts to limit variability in emissions – or at least upward 

variability – by maintaining and operating the source carefully to control emissions. Yet, as both 

EPA and the D.C. Circuit have recognized, operator training and care and source maintenance do 

operate to control emissions. By using the UPL, EPA ignores the effect of operator training and 

care and source maintenance on emission levels. Doing so is just as unlawful and arbitrary as 

setting floors that ignore the effects of cleaner fuel use; it results in floors that do not reflect the 

best sources’ actual performance.
35

Commenter 0508 stated that the agency has not set the new source floor at the emission achieved 

in practice but rather the 99 percent UPL. Although it may be permissible to set new unit floors 

“at a level that reasonably estimates the performance of the ‘best controlled similar unit’ under 

the worst reasonably foreseeable circumstances,’” CKRC, 255 F.3d at 863 (quoting Sierra Club, 

167 F.3d at 665), the UPL is not an estimate of what the single best unit actually “achieved in 

practice” under any circumstances. By definition, it is a “prediction” of the level EPA expects all 

future tests by that unit to fall below. 42 U.S.C. § 7429(a)(2); Sierra Club, 479 F.3d at 880.

Response: EPA did not propose nor did we request comments regarding the utilization of the 

UPL. Since EPA did not repropose, reexamine, or otherwise reconsider this issue, EPA is not 

addressing these comments here. EPA also notes that the applicability of the UPL to the PM 

standard was litigated and resolved in EPA’s favor in the PCA v. EPA litigation. 665 F. 3d at 

189. 

3.9 PM: Selection of Best Performing Sources was done Incorrectly

Commenter 0508 stated that EPA’s floor approach is also unlawful and arbitrary in other 

respects. First, EPA selected the best performers based on each source’s lowest test result but 

then measured the best sources’ actual performance based on their average test results. EPA’s 

use of different measures of performance to identify the top sources on the one hand and to

evaluate their performance on the other is inconsistent, irrational, and unexplained. By using the 

lowest test result to identify the best performers but the average test result to reflect their 

performance, EPA artificially increases the variability of the data on which it bases floors. 

Specifically, the data for the top twelve percent of sources has more variability than if EPA had 

picked the top twelve percent based on the best average test result, and as a result the variability 

factor and the floors themselves are also higher. Given that EPA’s choice affects the outcome of 

its floor analysis, the absence of a rational explanation for that choice is especially arbitrary.

Response: The commenter again addresses issues not proposed, reexamined, or otherwise 

reopened in this proceeding. The database and methodology for establishing MACT floors was 

done as part of the 2010 final rule. See Docket item EPA-HQ-OAR- 2002-0051-3403. The only 

issues here were the effect of removing CISWI kilns from the database and the appropriate 

compliance regime for the PM standard. If, against our view, some response is considered to be 

necessary, we also note that this comment is not accurate. The commenter incorrectly describes 

the approach used in determining the MACT floor. According to the commenter, EPA selected 

the best performers based on each source’s lowest test result but then measured the best sources’ 

actual performance based on their average test results. In fact, using all the test results we had for 

each kiln, we calculated the average emissions for each kiln for which we had data and ranked 

their average emissions from lowest average emissions to highest. (See Docket item EPA-HQOAR- 2002-0051-3403 for an explanation of the process by which the MACT floors for existing 

and new kilns were developed. See also Docket item EPA-HQ-OAR-2011-0817-0225 for an 

explanation of how the MACT floor was updated for this rulemaking. ). The best performing 12 
36

percent made up the MACT floor kilns. However, we repeat that EPA is not reconsidering or 

reopening this issue.

3.10 PM: Rounding-up of UPL is Unlawful

Commenter 0508 stated that EPA rounds up its emission test results for the purpose of setting 

standards even though the agency’s policy is to round them down for the purpose of 

determining compliance. Specifically, EPA rounds up UPL values less than 100 to one 

significant figure, and rounds up UPL values between 100 and 1000 to two significant figures. 

EPA’s decision to round up is unlawful. The CAA requires floors to reflect the emission levels 

achieved by the best sources not those emission levels rounded up to the nearest whole number. 

EPA’s departure from normal rounding practices by always rounding up in setting floors – i.e., 

rounding up whether the fraction is above or below one half – exacerbates that unlawfulness 

and is arbitrary. And the agency’s inconsistent approach to rounding for standard setting and 

compliance determinations is inconsistent, irrational, unexplained, and therefore arbitrary.

Response: EPA did not propose nor did we request comments regarding rounding and the UPL. 

This issue has not been reopened. If, against our view, some response is deemed necessary we 

note that rounding conventions are an area in which EPA has great discretion and the rounding 

techniques used in the 2010 rule (which are not reopened) were well within that discretion. 

North Carolina v. EPA, 531 F. 3d 896, 925 (D.C. Cir. 2008). We believe that when setting 

standards, it is appropriate to round up. Rounding down of emission test results would be 

essentially setting beyond-the-floor limits without the appropriate analysis of impacts. However, 

the issue is not properly raised in this proceeding, as explained above.

3.11 PM: Comment Regarding Lack of PM Data for Kilns

Commenter (0523) expressed concern that the cement industry submitted PM emissions data 

for all kilns under the current NESHAP program to the EPA, yet the EPA can identify only 28 

cement kilns, after removing kilns identified as CISWI. 

Response: These comments again address issues that were not reopened or reconsidered here. 

The issue of the proper database for the 2010 rule was addressed as part of that rulemaking. At 

issue here was which kilns were CISWI and needed to be removed from that database. 

If, against our view, some response is considered to be necessary, we note that the data set used 

for the 2010 consisted of the results for 45 kilns. After removing CISWI kilns, the data set 

consisted of PM data for 28 kilns. While it is true that all kilns must conduct annual PM 
37

emissions test, the data are not as readily available as the commenter implies. Results of annual 

performance testing are typically sent to environmental agencies at various levels of government 

including local and state agencies. Within state agencies, jurisdiction may be divided 

geographically into multiple responsible units. Test report results are not typically readily 

available and responsible agencies must be contacted and requests made for the data. This 

situation will be improving as EPA implements its centralized electronic reporting tool for 

emissions test results. Until that system is fully implemented, we will continue to rely on 

receiving from a combination of reports from government agencies and the industry. For the 

2010 rule we have collected data from both. We note that test results obtained from industry 

were in response to a 2007 information collection request (ICR), industry comments on the 

proposed NSPS for portland cement, and a 2003 survey of state agencies.

Comment: Commenter 0508 stated that for new plants, EPA’s floors must reflect the emission 

level achieved by the single best performing kiln in the category, not the best performing kiln 

for which EPA happens to have emissions information. EPA does not even claim to know that 

its new source floors reflect the PM emission level achieved by the best performing kiln in the 

category, nor could it plausibly advance such a claim without information for more kilns than it 

has.

Response: This issue was again not reexamined, reconsidered or reopened by EPA so no 

response is necessary. See 77 FR 42372 n. 3. If a response is considered necessary (against our 

view), then we note that the language of section 112 (d)(3) ) can reasonably be interpreted to 

refer to sources for which EPA has emissions data, since floors are to reflect the performance of 

the best controlled similar source “as determined by the Administrator”.

3.12 PM: Beyond the Floor Rejection due to Cost Effectiveness is Unlawful

Commenter 0508 stated that EPA’s statement without any discussion that beyond-the-floor 

standards “do not appear to be justified for the same reasons in the 2010 final rule” is 

undermined by the agency’s own description of its proposed revisions and the impact they will 

have on plants’ compliance strategies. In both the 2010 rule and the 2009 proposal, the agency’s 

rationale for refusing to set beyond-the-floor standards was that the beyond-the-floor standard 

would reduce the total PM emissions from cement plants by just three tons a year at a cost of

$576,000 per ton of PM removed, a “cost-effectiveness” the agency regarded as inappropriate.

First, EPA predicts that the proposed revisions would increase PM emissions by 135 tons per 

year. Setting beyond-the-floor standards at the level of the 2010 rule therefore, would result in a 

reduction of 135 tons per year, not three tons per year.

Second, EPA does not attempt to show that the incremental cost of achieving the 2010 standards 
38

would be unachievable within the meaning of § 112(d)(2). To the contrary, EPA states that 

changes to the PM standard will result in annual savings of just $4.2 million spread across the 

entire cement industry. Thus, the annual cost of a beyond-the-floor standard set at the level of the 

current standard would also be $4.2 million. That is approximately $42,000 on average for each 

of the nation’s 100 cement plants, which is scarcely a number that would render such a standard 

economically unachievable. Further, beyond-the-floor standards set at the current level would 

yield additional reductions of PM at a cost-effectiveness of approximately $31,000 per ton. EPA 

does not even claim that this level of cost-effectiveness justifies refusing to set beyond-the-floor 

standards, let alone provide any rational basis for any such claim. 

To the extent EPA is offering its 2010 cost-effectiveness rationale for its current proposal not to 

set beyond-the-floor standards, its proposal is not only arbitrary for the reasons given above but 

unlawful. Clean Air Act § 112 require the “maximum” degree of reduction in emissions that is 

“achievable” considering cost. 42 U.S.C. § 7412(a)(2). Far from giving EPA discretion to base 

decisions on whether to set an emission standard on its subjective view about whether the costper-ton of that standard is appropriate, this language unambiguously requires the “maximum” 

degree of reduction that can be achieved considering cost and the other statutory factors. EPA’s 

contention that it can reject beyond-the-floor standards merely because it views their costeffectiveness as inappropriate contravenes Congress’s plainly expressed intent and essentially 

rewrites § 129(a)(2) to provide a far greater level of discretion than the statutory text confers. 

Congress directed EPA to set standards requiring the “maximum” degree of reduction that is 

“achievable,” not the degree of reduction EPA considers “cost-effective,” and its decision must 

be respected. Barnhart v. Sigmon Coal Co., Inc., 534 U.S. 438, 452-53 (2002) (“[W]hen 

Congress includes particular language in one section of a statute but omits it in another section of 

the same Act, it is generally presumed that Congress acts intentionally and purposely in the 

disparate inclusion or exclusion”).

Response: Following proposal, the industry provided additional information on how the 

industry may alter control strategies in light of the changes to the emission standards and 

compliance period that we proposed. (Docket item EPA-HQ-OAR-2011-0817-0505). Thus, we 

were able to update our previous estimate of potential savings that was presented at proposal, 

which was not intended to represent the total potential industry-wide savings but was a narrow

example of how the proposed rule could reduce compliance costs. Specifically, EPA estimates 

that a beyond the floor standard set at the level of the original (2010 final rule) standard would 

only result in 138 tons per year – nationwide – of PM reduction (a value not questioned by any 

of the commenters). See Final Portland Cement Reconsideration Technical Support Document, 

December 20, 2012, page 1. We further estimate that the cost of achieving this modest 

incremental reduction would be approximately $37 million (the estimated cost savings 

attributable to the amended PM standard (including savings attributable to ancillary PM controls 

related to collection of PM from the control of Hg, THC, and HCl). See Final Portland Cement 

Reconsideration Technical Support Document, December 20, 2012, included in the rule docket, 

EPA-HQ-OAR-2011-0817. These total costs are high compared to the small nationwide 

emission reductions, and the cost effectiveness of these reductions is correspondingly high: 

approximately $268,000 per ton of PM removed. As explained in section V.A.3 of the preamble 
39

to the final rule, this is significantly higher cost effectiveness for PM than the EPA has accepted 

in other NESHAP standards. A beyond the floor standard at the level of the 2010 standard would 

also involve slightly higher energy use, although this is not a major factor in EPA’s decision. 

EPA is therefore not adopting a beyond the floor standard for PM at the level of the 2010 

standard. A standard even more stringent would likewise not be justified. See 76 FR 54988.

3.13 Mercury (Hg): Opposition to Beyond the Floor Standard

Two commenters (0505, 0511) objected to EPA’s decision to set the existing mercury floor at a 

beyond-the-floor level of 55 lb/MM tons clinker. Commenters stated that although EPA is 

proposing to the retain the existing source standard for mercury at 55 lb/MM tons clinker 

produced, the preamble concedes “the recalculated existing source floor is 58 lb/MM tons 

clinker produced.” As such, the commenter does not believe that EPA has justified its need to 

ignore its recalculated existing source floor and instead retain the 2010 limit as a “beyond the 

floor standard.” The commenter therefore opposes EPA‘s proposal to adopt the recalculated 

existing source floor.

One commenter (0511) stated that EPA, in the May 6, 2009 preamble, evaluated costs and 

economic impacts in determining whether to adopt a beyond-the-floor standard for mercury and 

concluded that a beyond-the-floor limit would result in the removal of an additional 3 lbs/year 

of mercury at an annualized cost of $1.254 million per year, or $420,000/pound (assuming 90 

percent system removal efficiency of a second ACI system) or $540,000/pound (assuming a 70 

percent system removal efficiency). EPA concluded, based on this analysis that a beyond-thefloor standard that was 3 pounds/year more stringent was not justified. The commenter does not 

believe that the economic analysis has changed since 2009 and that EPA should not go beyond 

the floor standard of 58 lbs/million tons clinker.

Response: See Preamble section V. B

3.14 Hg: Opposition to EPA’s Process of Setting the Standard

One commenter (0508) stated that should EPA elect not to set beyond-the-floor standards for 

existing plants’ mercury emissions and to set standards at the new floors, its standards would be 

unlawful. The commenter repeats its statements summarized above in regarding EPA’s use of 

the 99% UPL and use of variability (Section 3.9), use of sources’s lowest test results v their 

average test results in setting MACT floors (Section 3.10), failure of the UPL to reflect operator 

efforts to reduce upward variability (Section3.9), EPA’s practice of rounding up (Section 3.11) 

and EPA’s approach to setting MACT floors for new sources (Sections 3.9, 3.10).

Response: Regarding the commenter’s first concern, the final emission standard for mercury is 
40

set at the beyond-the-floor level of 55 lb/MM tons, not the floor level of 55 lb/ton. The 

commenter’s remaining issues are not part of this proceeding because EPA did not reconsider, 

reexamine, re-propose, or otherwise reopen them for public comment. 

3.15 Hg: Significant Cost Should Negate Beyond the Floor, Limit is Unachievable

One commenter (0511) stated they have extensive experience with mercury controls and have 

been operating and collecting data on some of the most effective mercury controls known to 

exist on a cement kiln, which it has previously shared with EPA. The commenter points out that 

in the July 18, 2012 proposal and background documents, EPA states that the collection of an 

additional 3 lbs of mercury per million tons clinker is as simple as adding an additional pound 

of activated carbon per million ACFM. 

The commenter stated that EPA’s assumption that the addition of extra carbon in an ACI system 

results in materially higher control efficiency is false. According to the commenter, they have 

performed extensive testing and the addition of activated carbon per million ACFM of exhaust 

gas has little or no impact on mercury emissions. The commenter states that for plants such as 

Ash Grove’s Durkee plant, there is no known add-on control technology at this time that will 

assure achievement of the standard on a continuous basis. Therefore, the commenter believes the 

difference between the floor and the beyond-the-floor level of control needs to be evaluated 

based on the costs of additional control devices, such as those in the 2009 preamble.

The commenter emphasized that two years of process and pollution control optimization using 

the most advanced ACI system employed anywhere in the cement industry, the commenter has 

been unable to consistently achieve the 55 lbs/million ton limit using both an ACI system and 

dust shuttling. The commenter emphasizes that operating fully optimized ACI and dust shuttling 

systems has enabled their plant to achieve an average removal efficiency of 96.6 percent over the 

twelve month period ending in July. The commenter stated a control efficiency of at least 99 

percent is required to reach the necessary compliance emission rates EPA outlined in the 

background document. 

Response: See Preamble section V.B.

3.16 Hg: Environmental and Energy Impacts Have Not Been Evaluated

One commenter (0511) disagreed with EPA’s conclusion that a beyond-the-floor standard 

results in no environmental or energy impacts. Even if increasing the carbon injection rate was 

adequate to achieve the additional 3 lbs/million tons of reduction, the commenter states that 
41

there are environmental impacts associated with the disposal of the mercury laden carbon waste. 

This material cannot be added back to the kiln or the mercury would be re-emitted. Therefore, 

the nearly 3 tons/week of spent carbon generated must be deposited into an appropriate 

hazardous waste landfill with substantial environmental impacts. 

If, as EPA stated in 2009 and the commenter believes is still accurate today, the only way to 

reduce mercury emissions by an additional 3 lbs/million ton clinker is through an additional ACI 

system or comparable control, the additional spent carbon impacts would be increased. Similarly, 

if dust shuttling is used to gain the additional level of control, that affected source must waste a 

significant amount of dust which would otherwise be used to produce cement. This too has 

significant environmental impacts. 

In addition, EPA ignores the energy impacts associated with operating supplementary controls 

and trucking waste material to landfills, as well as the impacts of treating the carbon to meet land 

disposal restriction standards. An ACI system for a 900,000 ton/year kiln consumes nearly 4 

million kWhr/year of electricity. Adding a second ACI system, therefore, has a very large energy 

impact that was not considered in evaluating whether to move beyond the floor. The commenter 

believes that if EPA took into account all of the costs, as well as the environmental and energy 

impacts associated with controlling beyond the floor, the agency would again conclude (as it did 

in 2009) that going beyond the floor to reach an additional 3 pounds of mercury reduction is not 

justified. For these reasons, the commenter stated that EPA has not provided adequate 

justification for setting a beyond-the-floor mercury standard for existing sources. If EPA 

nevertheless insists on moving to a beyond-the-floor mercury standard for existing sources, Ash 

Grove requests that the agency only do so for the subcategory of sources that have inherently low 

mercury limestone and that it create a separate subcategory subject to the floor for existing 

affected sources with inherently higher mercury limestone.

Response: We disagree with the commenter that a beyond-the-floor standard will have 

significant additional environmental and energy impacts. We believe that any increase in cost 

and environmental impacts associated with this final rule are small because the control 

equipment needed for mercury would not alter, would not need to be sized differently, and would 

need to perform on average nearly identically at either a 55 lb/MM tons clinker or a 58 lb/MM 

tons clinker level. Much of the commenter’s claims of increased impacts are based on an 

assumption of the addition of a second ACI system for mercury control. We think that it is 

unlikely that the industry will find it necessary to install a second ACI system, or any other 

control system, solely for the purpose of mercury control. Indeed, none of the kilns responding to 

the industry survey (PCA Comments App. D) indicated that they intended such a course. In our 

impacts analysis for the 2010 rule, we did assume that most kilns would install ACI for mercury 

and they would also install a wet scrubber for HCl control. We estimated that the wet scrubber, 

in addition to removing HCl, would also reduce mercury emissions, although that was not their 

intended target. The commenter did not provide any data on facilities that were planning to 

install a second ACI system as part of their compliance strategy, so the commenter’s arguments 

are largely theoretical, and as noted, no kiln claimed that it intended to install an additional ACI 
42

system for mercury control as a result of the proposed mercury beyond the floor standard in the 

specific survey data provided as an Appendix to the commenter’s comments.

4

3.17 Hg: Comment Regarding 63.1349(b)(5)(ii)

Commenter (0505 - Appendix G) stated that equation 6 is missing the variable, P, kiln clinker 

production rate.

Response: The equation has been corrected.

3.18 Hg: General Support

One commenter (0508) supported EPA’s decision to set the final beyond-the-floor standards at 

the level of the existing limit, 55 lb/MM tons.

Response: EPA has noted the commenter’s support for this standard.

3.19 Total Hydrocarbon (THC): Support for Including Union Bridge CISWI Kiln

One commenter (0505) supported EPA‘s proposal to retain the existing and new source limit 

for THC at 24 ppmv stating that there are sound reasons why it is appropriate – and correct – for 

EPA to include the Lehigh Union Bridge kiln in its redetermination of the THC limits. First, as 

EPA notes in the preamble, the variability of the emissions of this unit are indicative of cement 

kilns, whether they are CISWI units or NESHAP units. Therefore, it is appropriate to consider 

that variability whether setting a limit for CISWI units or NESHAP units.

The commenter (0505) stated that based on the revised definition of non-hazardous solid waste 

(NHSW) that EPA is now proposing to adopt in docket EPA-HQ-RCRA-2008-0329, 77 Fed. 

Reg. 80452, and is on the verge of finalizing as the criteria for what is and is not “solid waste”, 

Lehigh has determined that the alternative fuel (dry biosolids) used by this kiln are not “solid 

 4 Moreover, even as to the single high-mercury feed source (Ash Grove, Durkee Oregon), our cost analysis 

conducted for the 2009 proposal and 2010 final rule already assumed that this plant would have to install multiple 

control systems in order to meet the limit for mercury. See EPA Docket item 2002-0051-3438. Therefore, if in this 

particular case the ACI system cannot achieve the small additional reductions required, then the facility has other 

mercury control options available such as further dust shuttling or pretreatment. Neither practice would result in 

significant adverse non-air environmental or energy impacts.
43

waste” under the pending CISWI rule. Thus, on the reasonable assumption that EPA will not 

adopt a final definition of NHSW that is significantly different, Union Bridge will not be a 

CISWI unit when those rules are finalized. The Union Bridge kiln is, therefore, correctly 

considered in the setting of the NESHAP THC floor.

Commenter 0505 also stated that, if EPA were to adopt a limit below 24 ppmv, the number of 

RTOs needed by this sector will not only increase, but will increase significantly. As EPA is well 

aware, RTOs are not only extremely expensive to install, they also result in more emissions than 

they remove. EPA therefore has a significant, valid reason to adopt a standard which avoids the 

need for a large number of RTOs to be used; especially when there is no demonstrated 

alternative to controlling THCs from kilns.

Response: EPA agrees that the Lehigh Union Bridge kiln is not a CISWI kiln..,During 

the comment period, the company provided reliable information in its comments regarding the 

secondary materials it processes indicating that one of these kilns is in fact a cement kiln (so that, 

in fact, the EPA had properly classified it as a cement kiln in the 2010 rulemaking).5

 According 

to the company, the alternative fuel (dry biosolids) used by this kiln is not “solid waste”. 

Specifically, the commenter stated that the proposed NHSM amendments would allow more 

flexibility regarding the comparison of groups of contaminants levels to traditional fuels and that 

EPA has re-proposed ranges of traditional fuel contaminant levels from EPA’s Office of Air 

Quality Planning and Standards (OAQPS) CISWI tables. EPA notes, however, that grouping of 

contaminants as well as contaminant comparisons based on ranges of traditional fuel 

contaminant levels from the OAQPS database is already allowable under EPA guidance 

implementing the existing NHSM rules so the same rationale applies under the original NHSM 

rule as well (see http://www.epa.gov/wastes/nonhaz/define/index.htm). Based on this 

determination, the limits set in the final 2010 rule (24 ppmv) will remain unchanged, since the 

database for the THC floor and standard is unchanged.

3.20 THC: Opposition to Including Union Bridge CISWI Kiln

One commenter (0508) stated that with respect to new plants, EPA’s primary argument is that 

although the plant it identified as the best performer for THC is a CISWI kiln, it is nonetheless 

“similar” to non-CISWI kilns within the meaning of § 112(d)(3). For the reasons given by the 

commenter on EPA’s mercury standards, the commenter does not oppose treating CISWI kilns 

as “similar.” 

The commenter stated that CAA § 112(d)(3) unambiguously requires EPA’s floors for new 

sources to reflect the emission level achieved by the single best performing source, not the 

source that in EPA’s view is “representative of variability” experienced by other sources. If EPA 

determines that it must exclude the Union Bridge kiln from its floor analysis because it does not 

 5 The company burns dried biosolids as a fuel which are not classified as solid wastes. Refer to the Docket, No. 

EPA-HQ-OAR-2011-0817-0482.
44

believe that kiln is “similar” for the purposes of § 112(d)(3), the agency cannot base floors on 

that kiln regardless of whether the agency believes that kiln’s variability is more representative 

than the next-best kiln’s. Likewise, if EPA concludes that the Union Bridge kiln is not the best 

controlled “similar” kiln, it cannot refuse to base floors on the next best-performing kiln (the 

Suwannee kiln) regardless of whether it thinks the Union Bridge kiln’s variability is more 

representative. In those circumstances, EPA could refuse to base new source floors on the 

Suwannee kiln only if that kiln were not “similar,” and EPA does not make any claim that the 

Suwannee kiln is not similar to other kilns in the category, far less provide any rational basis for 

such a claim. 

The commenter stated that EPA’s argument for refusing to set existing source floors at the level 

achieved by the best performing twelve percent of non-CISWI kilns for which it has emissions 

information is egregiously unlawful and borders on contemptuous of the Court’s decisions in 

PCA and in NRDC. Existing source floors must reflect the average emission level achieved by 

the relevant best performing sources. If the Union Bridge kiln is not among these sources – and 

EPA claims it is not – the agency may not base floors on the performance of the Union Bridge 

kiln in any sense. 

The commenter stated that because § 112(d)(3) requires floors to reflect the “average” emission 

level achieved by those sources, EPA may not set standards at a different level just because a 

source that is not among the relevant best performers (Union Bridge) has more variability. Nor, 

contrary to EPA’s claim, does the brick kilns decision hold or even suggest that EPA may import 

the variability of a source that is not even in a category to change the average emission level 

achieved by the relevant best sources that are in that category. Here, far from using the emission 

levels of the Union Bridge to estimate the variability to estimate the variability of the best 

performing non-CISWI kilns, EPA is expressly excluding these emission levels from its floor 

calculations. As a result, it is violating the requirements of § 112(d)(3) by seeking to import the 

Union Bridge’s variability into the floor calculations. EPA has not demonstrated any relationship 

between the variability of Union Bridge kiln and the variability experienced by the other kilns, 

and the mere fact that EPA has more data for the Union Bridge kilns does not demonstrate such a 

relationship.

Response: In our 2010 rule, the THC MACT floor was based on the Union Bridge kiln being 

classified as a Portland cement kiln. Since the facility has now sent information that they are not 

a CISWI kiln as was assumed for the July 2012 proposal, the 2010 determination of the THC 

MACT floor stands and issues of variability for existing sources is moot. EPA did not otherwise 

reopen the issue of methodology or data used to develop the standard in the 2010 final rule. 

Based on this information, the limits set in the Final 2010 rule (24 ppmv) will remain unchanged.

3.21 Organic Hazardous Air Pollutants (oHAP) Alternative to THC: General 

Support
45

Two commenters (0475, 0507) supported the EPA’s proposal to allow existing and new cement 

sources the option to comply with either a THC or an o-HAP standard.

Commenters 0505 and 0523 supported the adjustment of the alternative organic HAPs (oHAP) 

limit from 9 ppmv dry at 7 percent O2 to 12 ppmv dry at 7 percent O2 to take into account the 

method detection capabilities of the compliance test methods prescribed in the rule. The use of 3 

times the representative detection limit (RDL) to establish the limit is consistent with the 

approach that was used when setting the limit for HCl in the previous rulemaking. The RDLs as 

presented in the EPA technical support document for the EPA Methods 320 and 18 are 

representative of the test method capabilities. Increasing the limit to 12 ppmv allows for the use 

of currently available emissions testing procedures and technologies to measure the regulated 

organic HAPs with certainty sufficient to demonstrate compliance.

Response: EPA has noted the commenters’ support for this standard.

3.22 o-HAP Alternative to THC: Use of Three Times the RDL is Unlawful

One commenter (0508) stated that EPA’s proposal to raise the oHAP limit to 12 ppmvd 

because it is three times the RDL does not claim to reflect the emission level actually achieved 

by the relevant best performing sources and are therefore unlawful. Further any claim that such 

floors do reflect the relevant sources’ emission levels would be arbitrary. EPA provides no 

record basis for such a claim, far less demonstrates the validity of any such claim with 

substantial evidence. Indeed, the agency’s treatment of non-detect levels has no relation to the 

statutory requirements and amounts to an attempt by EPA to elevate its own policy views over 

Congress’ plainly expressed intent that standards must reflect the best sources’ actual 

performance.

Response: First, the commenter is incorrect in characterizing this issue as one of performance. 

It is an issue of measurement reliability. The EPA disagrees with the commenter and has 

established the RDL and 3xRDL evaluation process as part of MACT floor development to 

guide decision making in addressing measurement variability and reliability. The RDL is 

determined from the average of MDL’s reported in the MACT floor data set. This is not the 

best MDL reported for the MACT floor; there are approximately half of tests with better 

detection limits and half of tests with poorer detection limits. The RDL process was 

developed in this way in part to promote better method detection levels moving forward by not 

considering the higher half, and in part to provide the flexibility for sources to select testers and 

labs that are competitive and local rather than forcing the selection of the single best performing 

laboratory and/or tester. MDL is commonly defined as 3x the standard deviation of 7 

measurements of a sample blank. The 3x RDL process is based on the widely accepted 

definition of quantitation limit being 10 times the standard deviation of 7 measurements of a 

sample blank or 3.33 times the MDL . Refer to:
46

http://www.epa.gov/fem/pdfs/Env_Measurement_Glossary_Final_Jan_2010.pdf.

When we set an emission limit using 3x RDL it is because the UPL calculation, designed to 

assess source and operational variability, has determined that the floor would otherwise be set 

below the level of quantitation reasonably achieved in practice by the test method. By using the 

3 x RDL value we have determined that a level of quantitation reliably measured by the test 

method is the suitable emission floor as that test method is the determination of compliance 

necessary to write and enforce the rule. We do believe that measured values reported above the 

MDL but below the 3x RDL value are useful information, but we hold that they have higher 

degrees of uncertainty than those values at or above the 3x RDL level. 

The commenter’s claim that the oHAP alternative limit established in the 2010 final rule is 

improper was not reopened or reexamined by EPA in this proceeding. The only issue addressed 

by EPA here with regard to that standard was whether the promulgated standard could be 

measured reliably (as just explained). Consequently, EPA is not further addressing the issue 

here. 

3.23 oHAP Alternative to THC: Significant Opposition to the Use of Three Times 

the RDL

One commenter (0513) stated that EPA has not considered the enforceability of emission 

standards that have been arbitrarily set using the three-times-RDL approach that the EPA is 

using for the organic HAP emission standard. The commenter stated that the EPA has not 

adequately demonstrated the reliability and accuracy of the EPA test methods at such a narrow 

margin above the MDL of the methods. The three-times-RDL approach can set the emission 

standards close to or even less than the practical quantitation limit (PQL). Even if the emission 

standard is equivalent to the PQL, EPA’s own technical experts recognize the need for an 

additional margin between an emission standard and the PQL. If the three-times-RDL approach 

establishes an emission standard less than a method’s PQL, compliance with the standard 

becomes indemonstrable. 

EPA’s three-times-RDL approach is arbitrary and establishes emission standards near the MDL 

without determining the actual accuracy of the required methods at such low concentrations. 

While PQL is not typically defined in EPA test methods, the generally accepted definition of 

PQL is the minimum level that can be reported with a specified degree of confidence or 

certainty. It is also generally accepted that a method’s PQL will be greater than the MDL. While 

the PQL for some EPA methods has been estimated, such as the case with Method 5, many EPA 

stack test methods do not have a documented PQL. Therefore, the EPA cannot ensure that an 

arbitrary factor of three will establish an emission standard greater than the PQL of such 

methods. 
47

EPA should determine the PQL of the required methods before assuming that the methods are 

sufficiently accurate to demonstrate compliance with an emission standard established using the 

three-times-RDL approach. A fundamental flaw in the EPA’s reasoning for the three-times-RDL 

approach is that if the emission standard is near or less than the method PQL then the only 

emission data that can show compliance with the standard are data that is by definition of 

unknown certainty. If the data needed to determine compliance is questionable by default then 

enforceability of the emission standard is severely compromised unless the emission test results 

are substantially above the emission standard and clearly demonstrate non-compliance.

Technical support documents contained in the docket from EPA test method experts indicate that 

the margin between an emission standard and the MDL of the method used to demonstrate 

compliance should be greater than the factor of three. (The commenter included several 

references to comments about the EGU MATS rule.) In EPA’s technical memorandum 

regarding the capabilities of PM CEMS (EPA Docket ID No. EPA-HQ-OAR-2011-0817-0187) 

EPA staff also provided an analysis of the capabilities of EPA Method 5 for determining PM 

emissions. The memorandum indicates that a one-hour Method 5 test run would have an MDL of 

approximately 2 mg/dscm and that this MDL would equate to a PQL of approximately 6 

mg/dscm using a three-times-MDL approach. The memorandum also states that to “achieve a 

PQL of 1 mg/dscm (as would be necessary to demonstrate compliance with a 2 to 3 mg/dscm 

emission limit), one would need to conduct a Method 5 test of 6 hours or longer.” The analysis in 

the EPA technical memorandum indicates that the overall recommended margin between the 

Method 5 MDL and the emission standard is 6 – 9 and not an arbitrary factor of three. 

Depending on stack conditions and the Method 5 sample train parameters, a six-hour test run 

could exceed 5 dscm. 

While Method 5 sensitivity can be improved by sampling a greater volume of stack gas, longer 

Method 5 test runs raise practicality concerns. Using the same assumptions from the EPA 

technical memorandum, each Method 5 test run would have to be 12 – 18 hours in duration to 

achieve the recommended PQL. Method 5 was not designed to be conducted for test runs of this 

duration. 

The commenter encourages the EPA to consider the technical limitations of Method 5 as well as 

the other required methods for demonstrating compliance when setting emission standards in the 

current Portland cement NESHAP proposed rulemaking as well as in the recently announced 

reconsideration of the MATS rule new unit emission standards.

Commenter (0513) stated that EPA has made significant errors in determining the method RDL 

values in the technical support document entitled Data and procedure for handling below 

detection limit data in analyzing various pollutant emissions databases for MACT and RTR 

emission limits (EPA Docket ID No. EPA-HQ-OAR-2011-0817-0142). The commenter 

provided an example using the RDL determination for Method 26A for hydrogen chloride (HCl) 

and chlorine (Cl2).
48

Commenter (0513) stated that in the EPA document Portland Cement Reconsideration Technical 

Support Document (EPA Docket ID No. EPA-HQ-OAR-2011-0817-0225), the EPA’s indicates 

that using the three-times-RDL approach to set the organic HAP limit would result in “a standard 

where the method would produce measurement accuracy on the order of 10 to 20 percent, similar 

to other EPA test methods and the results found in the ASME ReMAP study.” The commenter 

states that EPA’s claim of accuracy for Methods 18 and 320 in the technical support document is 

baseless and without any scientific validity. According to the commenter, the ReMAP study only 

evaluated a limited set of EPA reference methods: Methods 5 and 5i for particulate matter; 

Method 23 for dioxin and furan; Method 26 for hydrogen chloride; Method 29 for multi-metals; 

Methods 101a and 101b for mercury; and Method 108 for arsenic. The EPA apparently has 

extrapolated the ReMAP study to apply to all EPA reference methods, yet the EPA has provided 

no technical basis for making such an extrapolation. In the case of the organic HAP emission 

standard for the Portland cement NESAHP, Methods 18 and 320 use sampling procedures, 

analytical technology, or instrumentation that is completely different from the methods evaluated 

in the ReMAP study.

The final report of the ReMAP study does not support EPA’s claims regarding the accuracy of 

the reference methods that were included in the study. The data presented in the ReMAP study 

shows no indication that the study evaluated the methods at concentration levels near three times 

the RDL. For example, the ReMAP study evaluation of Method 26 only included data for HCl 

concentrations at 1 mg/dscm, or a 1000 μg/dscm. However, the EPA technical support document 

on determining the three-times-RDL values shows the three-times-RDL value for a Method 26 

test to be between 83 – 250 μg/dscm. Further, the MATS rule does not allow Method 26 for HCl 

testing on coal-fired boilers. Either the isokinetic sampling HCl method, Method 26A, or the 

instrumentation methods Method 320 or ASTM D6348-03 are required for compliance 

demonstrations on coal-fired EGUs and these methods were not evaluated in the ReMAP study.

Response: EPA previously promulgated the final 2010 HCl limit using three times the RDL. 

Further, for the purposes of this rulemaking comments related to Method 26A are not relevant 

since this rulemaking does not list Method 26A as a method to conduct performance testing.

The EPA feels that the commenter may misunderstand the Method 5 level of quantitation as 

described in the December 13, 2011 memorandum from Peter Westlin and Ray Merrill (EPA 

Docket item EPA-HQ-OAR-2011-0817-0142). With a level of detection at 1mg/m3 and a level 

of quantitation at 3mg/m3, a tester need only sample for one hour to provide the opportunity for 

their sample train to collect three milligrams of sample mass. If the target is 1.5 milligrams per 

cubic meter, the tester would run for two hours, and so on. We assume that a one hour Method 

5 test will collect approximately one cubic meter of stack gas and have based our guidance on 

that basis. Using this logic, a 12 hour Method 5 test would be able to demonstrate PM levels as 

low as 0.25 milligrams per cubic meter. 
49

The EPA acknowledges that the commenter makes the point that the ReMAP study only 

addressed isokinetic/manual methods that utilize analytical technologies different than M18 and 

M320. While this is true, the EPA would also point out that manual methods 1-4 commonly 

support Method 18 and Method 320 data with measurements of flow, molecular weight, and 

stack gas moisture content as they support the test methods listed in the ReMAP study. In the 

case of Method 18, each set of test data includes a recovery study demonstrating a site-specific 

accuracy within 30% which is data set specific and answers the question as to the quality of data 

at the low levels. The same is true for Method 320 where dynamic spiking must be performed 

and results achieving a +/- 30%method validation. 

As such, these test methods are considered to be self validating and limited by the QA and QC 

information determined through the individual sample analysis, not by independent study such as 

ReMAP. The analytical approaches used in method 18 and method 320 are well suited to a 

laboratory determination of MDL and, thereby, determination of a level of quantitation for the 

test method. Our analysis of this, as described in the proposed rule, provides for a fundamentally 

sound value of the emission limit, at 12 ppmv. For more discussion on RDL and 3x RDL see 

response to 3.24 above. 

3.24 Hydrogen Chloride (HCl): General Support of Standard

The commenter (0505) had significant comments regarding the capability of HCl CEMS and 

PS-15 to be used to demonstrate continuous compliance with the 3 ppm emission limits (refer to 

Comment 4.22). However, the commenter supported the concept that the limit should not be 

below the method detection limit (MDL) of the required monitoring method for both new and 

existing sources.

Response: EPA did not reopen, reconsider, or otherwise reexamine the issue of a compliance 

monitoring regime for HCl in this proceeding. EPA is consequently not addressing these 

comments here. 

One commenter (0508) stated that because removing the CISWI kilns did not change EPA’s 

floor calculations for hydrogen chloride, the agency proposes to leave the existing HCl 

standards unchanged. The commenter supports this decision.

Response: EPA has noted the support for this standard.

3.25 Start-up/Shutdown: Opposition to Numerical Standards / Support for Work 

Practices
50

Commenters (0475, 0494, 0505, 0506, 0507, 0523) stated that work practice standards should 

be imposed (not emission standards) during startup and shutdown because there is no data 

available to establish numerical limits.

Commenters (0494, 0507) noted that any numeric limit should be based on actual data gathered 

during startups and shutdowns, and measurement of emissions during startup and shutdown 

poses significant technical problems, mainly based on CEMS calibration issues, and the short 

duration of startups and shutdowns. 

Commenters (0505, 0507) stated that EPA has clearly stated in other MACT determinations that 

they cannot establish emission standards during startup and shutdown periods if they lack data to 

establish said standards. In the preamble to the Mercury and Air Toxics Standards (MATS) for 

electric generating units (77 Fed. Reg. 9381, February 16, 2012), EPA defends its decision to 

adopt work practice for electric utility boilers in lieu of emission standards during startup and 

shutdown periods because of insufficient data on emissions during startup and shutdown. 

Similarly to the MATS situation, EPA lacks any viable data on cement plant source emissions 

during startup and shutdown events.

Commenters (0505, 0507) stated that EPA believes that commenters may have a burden under 

CAA §112(h) to demonstrate why it is “not feasible” to prescribe numeric emission standards for 

startup and shutdown. 77 Fed. Reg. at 42383. The “not feasible” language in §112(h), however, 

is directed to emission standards in general and does not speak to the issue of startup and 

shutdown. Moreover, EPA‘s choice of work practices in the MATS context, as noted above, was 

based on the lack of sufficient emissions data, not “feasibility.” We believe EPA is thus fully 

authorized – and indeed required – to treat the portland cement industry just as it treated electric 

generating units and issue work practice standards for startup and shutdown events.

Commenter (0507) noted that a large portion of emissions from cement plants originate from the 

raw materials and not the fuels, so emissions during startup and shutdown periods will be 

considerably lower than during normal operations.

Commenter (0523) stated that the work practice standard should address site-specific kiln 

operations during the period when raw materials are not being continuously introduced into the 

kiln system. The commenter suggested that the work plan would address actions taken to 

minimize emissions during startup or shutdown.

Commenter 0506 stated that it is infeasible to gather data during startup, shutdowns, or 

malfunctions simply because there are no EPA approved methods to make measurement during 

non-steady-state conditions and malfunctions, by definition, are sudden and infrequent. In the 

final Hospital/Medical/Infectious Waste Incinerator rule, EPA agrees with this. At 74 Fed. Reg. 
51

51,394, EPA states “It would be very difficult to do any meaningful testing during such an event 

because the exhaust flow rates, temperatures, and other stack conditions would be highly 

variable and could foul up the isokinetic emissions test methods (thus invalidating the testing).” 

EPA followed this logic in the industrial boiler rule (76 Fed. Reg. 15,613) where they 

determined that it is not technically feasible to complete stack testing during periods of startup 

and shutdown due to the physical limitations and the short duration of the startup and shutdown 

periods. As a result, they set work practice standards for startup and shutdown events in this 

final rule. The commenter believes the same sets of circumstances are applicable to this rule and 

suggest that EPA set work practice standards in this final rule for startups and shutdowns. The 

commenter also believes that EPA should make a similar choice for malfunctions since we 

believe that malfunctions create the same set of circumstances pertaining to gathering data as do 

startups and shutdowns.

Response As discussed in the section IV.C of the Preamble to the final rule, we agree with the 

commenters that the operation of kilns at cement manufacturing plants is very different from 

other types of processes that involve combustion sources such that manual or continuous 

emission tests do not provide reliable and replicable data for the regulated HAP and HAP 

surrogates during cement kilns’ startup and shutdown periods..

3.26 Start-up/Shutdown: Support for Numerical Standards / Opposition to Work 

Practices

One commenter (0508) stated that EPA said it is amending the PM standards for startup and 

shutdown to be “consistent with” the revised PM standards for normal operations. Because the 

revised PM standards are unlawful and arbitrary for the reasons given by the commenter, 

revising the startup and shutdown standards to be “consistent” with them would also be 

unlawful and arbitrary. Further, relaxing the PM standards for startup and shutdown violates § 

112(d)(7) for the reasons given above. In addition, EPA does not even purport to show that the 

revised startup and shutdown standards comport with § 112(d)(3) far less demonstrate with 

substantial evidence that they do so, as the agency must. Even assuming that EPA could revise 

the startup and shutdown standards to be consistent with the agency’s revised PM standards for 

normal operations, the agency does not explain why it believes that they are “consistent.”

One commenter (0508) stated that EPA solicits comment on whether it should set work 

practice standards for startup and shutdown because emission standards are not feasible to 

prescribe or enforce. The commenter stated that CAA § 112(h) allows EPA to set work practice 

standards instead of emission standards only if it is “it is not feasible . . . to prescribe or enforce 

an emission standard,” because “a hazardous air pollutant or pollutants cannot be emitted 

through a conveyance designed and constructed to capture such pollutant,” or “the application 

of measurement methodology to a particular class of sources is not practicable due to 

technological and economic limitations.” 42 U.S.C. § 7412(h)(1)-(2). Nothing in the record 

shows that it is not feasible to prescribe or enforce emission standards during startup and 

shutdown nor does EPA even so claim. Accordingly, setting work practice standards instead of 
52

emission standards would violate § 112(h).

Commenter (0518) states that EPA is opening the door to dropping numerical emission 

standards during startup and shutdown, substituting “work practices” instead. In addition, the 

agency is proposing that “Monitoring during startup and shutdown would be accomplished by 

recordkeeping” (pages 82-83). The commenter states that these changes would be extremely 

irresponsible given that HAPs emissions are highest during these events. It is essential to have 

meaningful and protective limits during startup and shutdown. 

Response: As discussed in the Preamble section IV.C, EPA regards situations where a 

measurement may yield a value which is analytically suspect or so variable as to be arbitrary as 

being a situation where measurement is not “technologically practicable” within the meaning of 

section 112 (h)(2)(B) of the Act. Unreliable measurements raise issues of practicability and of 

feasibility and enforceability (see section 112 (h)(1)). 

Regarding the comment that emissions are highest during startup and shutdown, the EPA notes 

that emissions are not highest during these events at cement kilns since the primary source of 

emissions (raw materials) are not being added continuously to the kiln until the startup period is 

over (as per the regulatory definition of “startup” for this industry) and kilns burn cleaner fuels 

during startup than are used during normal operation. Thus, cement kiln emissions are lowest

during these events.

3.27 Start-up/Shutdown: Opposition to Steady State Limits Being Applied Startup/Shutdown

One commenter (0506) stated that EPA’s proposal to require Portland cement kilns to comply 

with what are essentially the same emission standards during periods of startup, shutdown, 

malfunction, and steady state conditions is neither logical nor lawful. MACT floor standards 

must be based on evidence that sources have already achieved them. However, EPA’s statement 

that sources can meet the standards during startup, shutdown, and malfunctions is not based on 

any data (at least there is no data in the record to show this). In fact, it is most likely wrong. 

The commenter stated that before the court’s decision in Sierra Club v. EPA, 551 F.3d 1019 

(DC. Cir 2008) (“SSM Decision”) the DC Circuit had consistently held that technology-based 

standards must contain exemptions or less stringent standards during periods of startup, 

shutdown, and malfunction (SSM) than would usually apply during steady state periods.

Now that the court has decided that MACT compliant standards must apply during periods of 

SSM, the Agency must develop standards that are “achievable” with this ruling in mind. The 

court has stated that for standards to be “achievable,” they must be achievable under the most 
53

adverse circumstances which can reasonably be expected to recur, Sierra Club, supra, 665 citing 

National Lime Ass’n v. EPA 627 F2.d 416 (D.C. Cir. 1980) (“National Lime I”).

The commenter (0506) provided examples of times when cement kilns may not be capable of 

complying with standards during SSM, such as bypassing baghouses until gas temperatures are 

above the condensation point. EPA states in the preamble that these units will not be feeding raw 

material during startup and shutdown and typically use cleaner fuels than used during normal 

operations (77 Fed. Reg. at 42.370). EPA is correct in both of those assertions. However, there 

are two major flaws in EPA’s reasoning.

The first is that even when using a cleaner fuel (e.g., natural gas), the combustion process is 

inefficient when starting up. Until ideal combustion conditions can be met in the combustion 

chamber (adequate temperature and turbulence), the combustion process will be incomplete. 

While this should not impact fuel-derived hazardous air pollutants (chlorine and mercury), it will 

impact the emissions of organics and possibly PM. As stated earlier, it is also not possible for 

certain air pollution control devices to work until a certain temperature and gas flow rates are 

achieved. 

The second is that EPA did not include emissions data during either startup or shutdown in the 

development of these standards; all data was collected under steady-state conditions. Since 

emissions under non-steady-state conditions may vary significantly, they could significantly alter 

the Agency’s calculations. As such, the standards are not properly set. Thus, from a physical and 

legal standpoint, it makes no sense to group startup, shutdown, malfunctions, and normal 

operation events under essentially the same set of standards.

One commenter (0508) stated that if EPA’s position that kilns’ actual emissions during startup 

and shutdown should be much less than in normal operations because feed contributes so much 

to emissions and if EPA insists on promulgating separate standards for startup and shutdown, it 

underscores that the emission standards applicable to startup and shutdown should be more 

stringent, not less stringent, than those that apply during normal operations. All of EPA’s 

numerical emissions standards must fully comply with the stringency requirements of § 

112(d)(2) and (3). EPA’s revised standards for startup and shutdown do not satisfy the floor 

requirements of §112(d)(3); EPA does not show or even claim that they reflect the emission 

level achieved by the relevant best performing plants. Likewise, they do not satisfy the 

requirements of § 112(d)(2); EPA does not show or even claim that they reflect the maximum 

degree of reduction in emissions that can be achieved. 

Response: Regarding the commenter’s statement on the inefficiency of combustion when 

startup, the EPA agrees and the final rule defines the period of startup to include the period when 

the ID fan is running and fuel combustion is occurring in the kiln’s primary combustion chamber
54

3.28 Start-up/Shutdown: Justification for Suggested Work Practices

Commenter (0507) discussed work practice requirements: (1) the operation of a pollution 

control device during startup and shutdown is a viable work practice as long as EPA recognizes 

that some pollution control devices require exhaust gases to have characteristics that will not 

contribute to degradation of equipment; (2) operators minimize startup and shutdown periods, 

because no product or profits are being made; (3) because kilns and situations are different, 

there is no single time period that can be defined for either startup or shutdown; (4) kiln 

operators are strongly motivated to follow manufacturer’s best practices when possible, as 

warrantees would be voided if they were not followed; (5) older kilns depend on operator’s 

long-time experience; (6) and operators will minimize the time periods under startup and 

shutdown to the greatest extent possible, while ensuring the safety of the persons working at the 

plant and the protection of the asset.

Response: The EPA acknowledges the commenter’s description of viable work practices in lieu 

of numerical emissions limits. We believe that the final work practices are largely consistent 

with the commenter’s suggestions. 

3.29 Start-up/Shutdown: Support for Recordkeeping

One commenter (0508) stated that EPA’s proposal to require reporting and recordkeeping for 

SSM events are necessary to prevent or reduce excess emissions during such events and to 

allow EPA, States, and the public to enforce violations of emissions standards. The commenter 

supports adding these requirements.

Response: EPA acknowledges the commenter’s support for the reporting and recordkeeping 

requirements. However, as discussed in preamble section IV. C, the final rule requires that 

affected sources comply with work practices to be in compliance during startup and shutdown 

instead of using recordkeeping to demonstrate compliance during startup and shutdown as was 

proposed.

3.30 Start-up/Shutdown: HCl Limit During Start-up and Shutdown

One commenter (0508) stated that EPA’s proposal to change the HCl standard applicable to 

periods of startup and shutdown from 0 to 3ppmvd contravenes §112(d)(7). Further, the new 

standard does not even purport to satisfy either the floor requirements in §112(d)(3) or the 

requirements for final standards in §112(d)(2) . It reflects neither the emission level achieved by 

the relevant best performing sources nor the maximum achievable degree of reduction. 
55

Response: The commenter is incorrect on both counts. First, section 112 (d)(7) does not 

preclude the EPA from correcting standards as it is doing here. The 2010 promulgated startup 

and shutdown standard was premised on no HCl being present in kilns during these periods, an 

assumption proven incorrect. See 77 FR 42382-83. Thus, those standards are literally impossible 

to achieve. Section 112 (d)(7) does not stand as a bar to amending such a standard. Second, as a 

factual matter, the limit of 3 ppmvd is the lowest level which can reliably be detected and so can 

only be a measure of best performance (since any lower measurement would have little reliable 

physical meaning for purposes of complying with the standard). See 75 FR 54984. However, 

this issue is now moot as the result of amending the standards to provide for work practices 

during startup and shutdown periods.

3.31 Clinker Piles: Additional Authorized Work Practices

Several commenters (0476, 0505, 0507, 0523) supported EPA‘s proposal to replace the clinker 

pile design and management requirements adopted in the 2010 rule with work practice 

standards. The commenter stated that there are other work practices, in addition to the five listed 

in the notice, that would be equally effective and could be also be utilized. In some cases, such 

practices have been incorporated into a particular plant‘s permit. Those and other such 

appropriate work practices should also be authorized by the final rule so that the final rule 

cannot be interpreted as having excluded (and therefore not permitted) additional work practices 

merely because they are not among the five specific work practices which the rule has listed. 

Commenter (0505) stated that the final rule should provide for an informal, expedited process 

by which individual plants could request the Administrator‘s approval of the plant‘s use of an 

additional work practice or practices.

Commenters (0476, 0507) asked that control measures in addition to the ones specifically 

outlined in the proposed rulemaking must be allowed by the Agency. The commenters suggested 

that the EPA consider providing a generic compliance option of “or other control measures 

approved for use by the Administrator.”

Commenter (0476) asked for clarification regarding a list of clinker pile controls for fugitive 

emissions in the preamble that are not reflected in the rule language at §63.1343(b)(2). The 

commenter requested that the regulatory language fully reflect the list of acceptable control 

measures found in the Preamble.

Commenter (0523) stated that fugitive dust control measures to minimize dust emissions from 

open clinker piles will be incorporated into the facility’s operations and maintenance plan, and 

that the facility should incorporate work practices to minimize dust emissions from clinker 

spills during material handling in its operations and maintenance plan.
56

Response: See Preamble section V.C.

3.32 Coal Mills/Alkali By-pass Stacks: General Support

Commenter (0507) supported the EPA’s determination that all coal mills that receive drying 

heat from a source other than the kiln gases should be regulated under the section 111 Subpart 

Y NSPS rule and not under the section 112 Subpart LLL NESHAP rule.

Commenter (0523) agreed that a cement kiln which commingles or returns its emissions from 

its coal mill along with all other emissions and discharges through kiln emission points would 

have to meet all of the NESHAP emission limits, and in the case of PM, the additional flow 

from the coal mill would be accounted for in the equation used to determine PM contributions 

from commingled flows.

Response: EPA has noted the commenters’ support for this standard.

3.33 Coal Mills/Alkali By-pass Stacks: Standard is Unlawful because no Data has 

been Collected

Commenter (0507) stated that the EPA should not be finalizing any coal mill standards based 

on this proposal, as there is no data in the record to support the coal mill provisions in the 

proposed rule. The commenter stated that to be faithful to the Administrative Procedure Act and 

CAA §307(d) rulemaking requirements, any rule that EPA may want to propose for coal mills 

in the future must be based on data and an awareness of which sources would be affected by 

various proposed requirements.

Response: The commenter is mistaken. The coal mill provisions, first of all, were properly 

noticed. See 77 FR 42383-85. Second, these provisions are not emission standards but rather a 

compliance mechanism for accounting for comingled emissions –similar to the equation for 

commingled emissions in the alternative PM standard (section 63.1343(b)(2)). Commenters are 

not claiming that the alternative PM equation involves a data-driven exercise. Thus, to reiterate, 

no new standard for either kilns or coal mills is involved but rather how to account for situations 

where emissions are commingled so that uncontrolled kiln or coal mill emissions (i.e. emissions 

greater than the level allowed by either the subpart LLL or subpart Y standards) are not emitted.

3.34 Coal Mills/Alkali By-pass Stacks: Request for More Time to Respond
57

One commenter (0505) stated that coal mills that have their own heat source or receive cooler 

air should be subject only to requirements under the coal mill preparation NSPS, 40 CFR Part 

60, Subpart Y. 

With respect to the two other configurations that EPA has proposed to address here, however, 

EPA needs to provide additional time for the commenter to consider and respond. As we 

discussed above, the issues involved with these configurations are highly involved. Further, what 

little discussion of the preamble provides for the proposal is confusing and does not provide an 

explanation for why EPA is addressing the two other coal mill configurations in the manner 

proposed to which the commenter can meaningfully respond. Accordingly, not only does EPA 

need to provide additional time for comment here, it clearly would be preferable for EPA to 

address and seek comment on the remaining two coal mill configuration through the publication 

of a separate notice that provides the underlying rationale that is currently missing from the 

proposed rule.

Response: There was ample public comment on this issue indicating both adequacy of notice 

and of time for response. Moreover, this issue was one which the industry itself asked EPA to 

reconsider. 76 FR 28326 (granting the industry’s request). Industry then negotiated a 

settlement agreement with EPA tying EPA to deadlines to complete the reconsideration process. 

Thus, EPA has acted on the issue on which the industry petitioned for reconsideration in the time 

agreed to by EPA and the industry in the settlement agreement. There is no valid basis for 

complaint about inadequate process under these circumstances.

3.35 Coal Mills/Alkali By-pass Stacks: Backsliding with PM NSPS Option

One commenter (0508) stated that EPA suggests that cement plants that choose to route their 

kiln emissions through a coal mill stack could be allowed to meet the 2009 new source 

performance standard for PM emissions. The commenter stated that such an approach would be 

lawful only if these NSPS are as stringent as or more stringent than lawful PM standards for 

cement plants under § 112. To the extent they are less stringent, allowing plants to meet them 

violates the anti-backsliding requirements of § 112(d)(7), the floor requirements of § 112(d)(3) 

and the beyond-the-floor requirements of § 112(d)(2).

Response: We consider the air pollution control technology used at subpart Y facilities, i.e., 

fabric filters, to be equivalent to the fabric filters used for PM control at portland cement plants. 

In the case of coal mills, the control device is capturing coal, which is the product of the coal 

mill. Thus there is a substantial incentive for efficiently capturing the coal. Nonetheless, we 

agree with the commenter and have revised Sections 1343(b)(2) and 1349(b)(1) as well as 

Section 60.62(b)(3). These revisions require that emissions from in line coal mills with separate 

stacks are combined with the alkali bypass and kiln emissions to meet the Subpart LLL PM limit.
58

3.36 Coal Mills/Alkali By-pass Stacks: Alternative PM Standard

Comment 0511 stated that the proposed language in. 63.1343(b)(2) appears to be missing 

language allowing coal mill exhaust to be accounted for in the alternative PM standard.

Response: The commenter is correct and section 63.1343(b)(2) in the final rule clearly identifies 

the sources that may be considered in developing a site-specific alternative PM emissions limit.

3.37 Raw Material Dryers: Support for Eliminating O2 Correction Factor

One commenter (0505) stated that they support EPA eliminating the oxygen correction factor 

associated with THC emissions from stand alone raw material dryers that was included in the 

2010 rule. The commenter stated their basis for that support in view of objections that are likely 

to be raised by other organizations.

Response: EPA has noted the commenter’s support for the removal of the O2 correction factor.
59

Section 4: Comments on Monitoring Requirements

4.1 Particulate Matter (PM): Opposition to Testing-based Standard

Commenter (0518) states that EPA’s proposal to rely on a performance test conducted every 

three years for PM compliance is unreasonable and does almost nothing in reality to assure 

compliance with any standard. 

Commenter (0523) requested that the EPA allow a source the option to use a PM CEM and 

comply with the proposed standard (0.07 lb/t 30-day rolling average) in lieu of the periodic 

stack test and surrogate.

Commenter (0518) states that the most egregious change is the proposed switch from 

continuous direct monitoring of PM to a “continuous parametric monitoring system” (CPMS). 

On page 38, EPA cites the potential technical issues associated with PM continuous emissions 

monitoring systems (CEMS), but it bases its assertions on the existing limit of “0.04 lb/ton of 

clinker [which] equates to 5 to 8 mg/dscm.” No analysis is provided for EPA’s proposed new 

limit of 0.07 lb/ton of clinker, which is almost double the existing limit. The detection 

capabilities and uncertainties cited by EPA will undoubtedly be significantly different between 

a limit of 5-8 mg/dscm and a limit of approximately 9 to 15 mg/dscm. Before throwing out 

direct monitoring altogether, EPA should analyze the inherent uncertainty of measurement at 

the proposed limit. Beyond this particular flaw, it is important to note that continuous monitors 

accurately measure very minute amounts of varying sizes of particulate matter in ambient air all 

across the United States, which leads one to question EPA’s assertions about the technical 

feasibility of PM CEMS. 

The commenter states that having asserted that PM CEMS are unreliable, EPA illogically 

proposes to use PM CEMS in conjunction with the monitoring of other operational parameters: 

“For monitoring continuous compliance, the rule would require PM CEMS equipment 

but ... that equipment would be used for continuous parametric monitoring rather than 

for direct measure of compliance with the numerical PM emissions limit” (page 44). 

The commenter states that the EPA proposes to allow facilities to submit a “site-specific 

monitoring plan” in which the reportable measurement output “may be expressed as milliamps, 
60

stack concentration or other raw data signal” [emphasis added]. Essentially, EPA is proposing to 

allow a facility to choose any operational parameter it desires and correlate it with PM emissions 

in a highly controlled performance test. On top of that, if a facility should exceed its preferred, 

site-specific parametric limit (after averaging over 30 days), it will be allowed to make multiple 

“adjustments,” until it achieves a limit it can easily comply with. It will not be considered a 

violation until it exceeds that limit four times, and even then, EPA would allow a facility to rebut 

any “presumption” of a violation. The commenter finds it outrageous and feel strongly that it is 

an unethical concession to industry pressure. 

The commenter believes that parametric monitoring is tailor-made for manipulation. This is 

exemplified by dioxin monitoring, which relies on temperature as a surrogate for actual 

emissions. The commenter noted that their local cement plant has repeatedly conducted 

performance tests designed to raise the operational limit, yet none of these tests were conducted 

at operational norms; production levels and fuel composition were manipulated to achieve 

desired outcomes. On several occasions, the kiln had upsets during testing that would have led to 

undesirable results, and so the testing was simply rescheduled for another day. The result is that 

the facility has achieved a surrogate limit that bears little correlation to actual emissions.

The commenter states that they find parametric monitoring so objectionable that they would 

prefer a return to continuous opacity monitoring—flawed as it is. At least it provided real-time, 

direct monitoring of PM emissions and held facilities accountable for their emissions 

exceedances. With the proposed changes, there is little or no accountability. Every kiln will have 

its own site-specific plan—some monitoring electric current, some monitoring stack gas 

concentration (or who knows what?). And that plan will be adjusted multiple times so that 

facilities can easily comply. This proposal is a bureaucratic nightmare! We predict that state 

agencies, many of which have had steep funding cuts, will not be able to provide adequate 

oversight for these ridiculously and unnecessarily arcane regulatory changes. 

The commenter states that because particulate matter is the arguably the most important pollutant 

emitted by cement kilns, it is imperative that PM be monitored both directly and continuously. 

The commenter feels very strongly that switching to parametric monitoring is simply a means of 

evading compliance with the standard. Without direct and continuous PM monitoring, facilities 

are highly unlikely to invest in the control technology needed to comply with the PM limit. EPA 

must not abandon appropriate, reasonable compliance assurance. That is the key to achieving 

cleaner air and better public health outcomes.

Response: The EPA is requiring PM performance tests annually in the final rule, with each 

performance test used to reevaluate the PM CPMS relationship to in stack PM concentration and 

reset the parametric PM operating limit. Sources wishing to use a PS 11 certified PM CEMS for 

compliance with the emission limit in the rule may apply for an alternate monitoring request 

using the process available in the Part 63 general provisions (40 CFR part 63.8 (f)). In using a 

PM CEMS as a CPMS to conduct continuous qualitative monitoring of PM concentration in the 
61

stack, we are not interested in specific output information from the instrument (e.g. lbs/ton 

clinker). We only need to know that PM concentration increases or decreases and the EPA 

recognizes that PM CPMS technologies are well suited to this task. The signal output from the 

instrument need not be correlated to PM concentration through PS-11 trials to achieve this, but 

rather we can accept the native signal output from the instrument, as is, in milliamps, and track 

that signal to determine trends in PM emissions. In this final rule we are requiring PM CPMS 

instruments to employ a 4-20 milliamp output, which is a standard electronic signal output 

common to many CEMS. With a PM CPMS the milliamp output would not represent an opacity 

value, but like an opacity analyzer, the milliamps would increase as PM concentration increases 

and decrease as PM concentration decreases. We can then monitor the milliamp signal while 

conducting a method 5 performance test and correlate the average milliamp signal to the average 

PM concentration during the testing. This relationship is notably coarser in terms of 

understanding the precise PM concentration in the stack through PS 11 certification, but the 

instruments’ sensitivity to changing PM concentration in the stack, and its changing milliamp 

signal output, does not deteriorate and may still be employed to qualitatively monitor PM 

emissions. PM CPMS technology is superior to opacity monitoring in terms of sensitivity to 

changing PM concentrations and in degrees of design freedom parameters such as light 

wavelength, scattering angle, and solid angle of detection.

(http://www.epa.gov/ttn/emc/cem/pmcemsknowfinalrep.pdf). The technology thus 

parametrically qualifies the performance of PM controls, and thus serves as a type of enhanced 

monitoring to document continuous compliance with the stack emission standard (see CAA 

section 114 (a)(3)) .

As the signal output is continuous and the measurement principle the same as a PM CEMS, the 

EPA disagrees with the comment stating that the signal is prone to manipulation. The output 

signal from a PM CPMS is no different than that from any other CEMS, except that it is not 

converted to a concentration value, but left in its raw milliamp state.

Finally, the EPA maintains that PM CPMS monitoring provides for continuous qualitative 

assessment of source PM emission controls and is protective of the emission standard – i.e. given 

the instrument sensitivity to detecting and reporting increases in the PM signal, there is virtually 

no likelihood of false negatives. . Never before has the public had the ability to see how PM 

emissions track between compliance tests and the EPA recognizes this as a significant step 

forward in emissions measurement related to PM standards. (Indeed, the sensitivity of the 

CPMS is such that EPA introduced a scaling factor into the rule to accommodate the situation of 

lower-emitting facilities, to avoid what in effect would be false positives – CPMS measurements 

where an increase in PM emissions would not implicate the emission standard itself. See section 

V.A.2 of the preamble to the final rule, and the following section of this document) .

Comment: PM: Support for Testing-based Standard. Commenter (0507) agreed with the 

EPA’s decision to move back to a stack testing-based standard and compliance demonstration 

methodology for PM.

Response: EPA has noted the commenter’s support for the stack testing-based standard.
62

4.2 PM: Request for Compliance Margin (Scaling) between Tested Value and 

Limit

Commenter 0505 supports EPA‘s decision to revise the 2010 rule and not require the use of 

continuous emission monitoring (CEM) in the manner that the 2010 rule had envisioned. PCA 

agrees with EPA‘s analysis supporting the proposed change set forth at 77 Fed. Reg. 42374. The 

commenter stated that this approach is similar to the compliance monitoring approach proposed 

for the organic HAP alternative and, just like the oHAP alternative, it too will expose 

complying cement kilns to excessive retests and create an unwarranted risk of erroneously being 

found to be in violation. The chief problems in this regard are as follows. 

First, no allowance has been made for the margin between measured PM emissions and the PM 

standard. Without such a margin, retests can be triggered based solely on an indication that 

emissions have increased. Because four retests are deemed to be a violation, complying kilns 

may actually be held to a more stringent standard than the one adopted by EPA.

Second, EPA creates a high risk of triggering frequent retests by basing the CPMS threshold on a 

1-hour value taken from the period of the annual performance test. Hourly CPMS values will 

have much more variability than 30-day CPMS. A single hour chosen from the period of the 30-

day average can vary from well-below the average to well-above the average.

Commenter 0505 stated that they discussed these issues at more length in their comments 

concerning the oHAP alternative and our proposed alternative methods to address the problems. 

The commenter stated that similar methods are needed to address the problems with PM CPMS. 

Based on the analysis presented in our comments concerning oHAPs, the commenter 

recommended that EPA take the following three actions:

• EPA should adopt a method to account for a compliance margin in the CPMS 

monitoring process. The commenter stated that as demonstrated for oHAPs, a 

compliance margin based on adjusted measurements can significantly reduce the risk 

that complying kilns are treated unfairly under the rule while protecting against the 

risk of inadequate monitoring. 

• EPA also should adopt a different method to determine the CPMS threshold used for 

compliance monitoring. This method would lengthen the time period for choosing the 

CPMS threshold.

• EPA should provide a compliance margin for sources that have PM emissions less 
63

than the limit. The approach of adding the compliance margin for the CPMS indicator 

can be the same one proposed for the alternative THC limit.

Commenter (0261) agrees with the agency’s intentions to eliminate the problematic issues 

discussed with the alternative monitoring approach to PM CEMs and PS11. However, the 

commenter suggests that rather than using the highest CPMS hourly value demonstrated during 

the three 2-hour Method 5 test runs, the agency consider the following approach:

1. First, demonstrate that the average of the Method 5 tests achieved compliance with 

the PM standard (i.e. 0.07 lb/ton clinker) during performance testing.

2. Second, establish the source-specific parametric monitoring emissions intensity in 

terms of CPMS units per lbs PM/ton clinker. Example: millivolts / [lb PM/ton 

clinker].

3. Scale this emissions intensity factor up to the LLL standards. Example: The PM 

monitoring device reads 5 millivolts average during the Method 5 testing. The 

measured average PM during those tests were 0.035 lb PM / ton clinker. The 30-day 

rolling average PM CPMS output value for purposes of compliance demonstration 

would become:

a. CPMS Compliance Point = [NESHAP standard ÷ Average Method 5 PM 

value] * Stack Test average millivolt

b. CPMS Compliance Point = [0.07 lb/ton clinker ÷ 0.035 lb / ton clinker] * 5 

millivolts

c. CPMS Compliance Point = 10 millivolts

The commenter believes that using another approach to determine the CPMS compliance point 

will likely result in the best-performers for PM emissions having a more strict standard in 

comparison with the 0.07 lb/ton clinker LLL standard. The commenter states that this approach 

also eliminates the likelihood that certain sources may establish a CPMS limit that actually 

exceeds the proposed numerical emissions limit of LLL and decreases the likelihood that better 

performers will be subject to a higher frequency of re-tests triggered by exceedance of the CPMS 

parametric limit.
64

The commenter concludes that at a minimum, the agency could establish a method to provide at 

least some credit in recognition of good PM emissions performance. A hypothetical example 

using the recommended approach is provided by the commenter. 

One commenter (0506) stated that the preamble and regulatory language do not appear to be 

clear or consistent on how to revise that operating limit based on subsequent tests. The 

commenter stated that the following would improve usability of PM CPMS:

a. The Agency should allow the use of all stack test data collected over time that has 

passed normal QA/QC requirements and their associated instrument reading to 

determine the most representative operating limit. 

b. The Agency should allow the use of all data collected over time that has passed 

QA/QC requirements to show that a PM CPMS can mean Performance Specification 

11. Once that demonstration has been made, the facility should be able to switch from 

a CPMS mode to a CEMs mode. 

c. The Agency should allow facilities to extrapolate the operating limit up to the 

standard using a simple ratio method.

Response: See Preamble section IV. A. and V.A.2, as well as the previous comment response. 

In short, these comments have identified a legitimate issue and EPA has introduced the scaling 

approach into the rule as a response.

4.3 PM: Request for Language Revision

Commenter (0476) requested that the EPA revise the proposed language in §63.1349(b)(1)(ii) 

to reflect testing under “conditions representative of normal operation.” The commenter noted 

that under the CAA NESHAP authority, EPA may only require testing under conditions 

representative of normal operations.

Response: While the text in amended 40 CFR 63.1349(b)(1)(ii) requires that the affected source 

be “operating at the highest load or capacity level reasonably expected to occur.”, and this is 

different than the text in the General Provisions of 40CFR 63.7 requiring “...normal 

operations...” we find that the text is reasonable when viewed in light of the guidance provided 

in the National Stack Test Guidance document, available at:
65

(http://www.epa.gov/compliance/resources/policies/monitoring/caa/stacktesting.pdf)

“...the CAA requires continuous compliance with emissions limits except where explicitly 

excused, EPA interprets applicable regulations to require that any stack test that is conducted 

within the scope of this guidance must demonstrate that a facility is capable of complying with 

the applicable emissions standards at all times.

4 

The NSPS and MACT programs require that 

performance tests be conducted under such conditions as the Administrator specifies based upon 

the representative performance of the affected facility. See 40 CFR §§ 60.8© and 63.7(e). The 

MACT program further defines representative performance as normal operating conditions. 

The Part 61 NESHAP program requires that emission tests be conducted “under such 

conditions as the Administrator shall specify "based on design and operational characteristics 

of the source.” Individual standards may more specifically define operating conditions under 

which performance tests should be conducted. In the absence of such specifications, the 

question often arises as to what operating conditions should be used when conducting a stack 

test. If operating conditions are not indicated by the applicable requirements in individual 

standards, they should be developed as part of the site-specific test plan. 

• In light of the fact that: (a) the Act requires that facilities continuously comply with emission 

limits; (b) the NSPS, MACT, and NESHAP programs all require that performance tests be 

conducted under such conditions as the Administrator specifies; and © the NSPS and MACT 

programs further require that such tests be conducted under representative operating 

conditions; EPA recommends that performance tests be performed under those representative 

(normal) conditions that: 

-represent the range of combined process and control measure conditions under which the 

facility expects to operate (regardless of the frequency of the conditions); and 

-are likely to most challenge the emissions control measures of the facility with regard to 

meeting the applicable emission standards, but without creating an unsafe condition. 

The following are factors that should be considered in developing the plan for a performance 

test that challenges to the fullest extent possible a facility’s ability to meet emissions limits. 

For a facility operating under an emission rate standard (e.g., lb/hr) or concentration standard 

(e.g., μg/m

3

), normal process operating conditions producing the highest emissions or loading to 

a control device would generally constitute the most challenging conditions with regard to the 

emissions standard. If operating at maximum capacity would result in the highest levels of 
66

emissions, operating at this level would not create an unsafe condition, and the facility expects to 

operate at that level at least some of the time, EPA recommends that the facility should conduct a 

stack test at maximum capacity or the allowable/permitted capacity.”

The logic of this guidance applies here. The stack test shows compliance while establishing 

ordinary operating variability. This provides means of establishing monitoring parameters 

correlated to the range of conditions which the kiln will experience in normal operation. See 

Cement Kiln Recycling Coalition v. EPA, 255 F. 3d 855, 867 (D.C. Cir. 2001) (in assessing 

sources’ performance for purposes of establishing MACT standards, EPA may permissibly allow 

sources to spike their hazardous waste feeds to “predict[t] their emissions under the worst 

reasonably forseeable circumstances”) .Therefore, the EPA disagrees with the commenter and 

will retain the language, as proposed, in the amended rule.

4.4 PM: Request to Remove Testing Requirement Following CPMS 

Commenter (0476) questioned the necessity of conducting a PM compliance test in the instance 

described in §63.1350(b)(1)(iii), when any deviation of the 30 process operating day PM CPMS 

average value occurs. The commenter stated that the PM CPMS value is effectively a surrogate 

for PM emissions, and compliance with the PM CPMS average value reflects compliance with 

the applicable PM standard. If a deviation of the average value is caused by a malfunction of the 

affected source or control device, and the required corrective actions are completed to reestablish compliance with the current PM CPMS average value, the source is deemed to be in 

compliance with the PM standard and the subsequent PM compliance test serves no purpose. 

The commenter requested that the EPA eliminate the requirement to conduct the subsequent PM 

emissions test following any deviation of the PM CPMS limit that is subsequently rectified with 

appropriate corrective actions.

Response: See Preamble section V.A.2. 

4.5 PM: Request for Reduced Testing Frequency due to Financial Burden

Commenter (0494) suggested allowing reduced stack testing frequency, particularly for small 

entities and area sources. The commenter stated that Method 5 stack testing for PM is a 

reasonable means of demonstrating compliance. The commenter requested a frequency of once 

every 30 months (similar to the D/F testing frequency) or a reduced frequency in subsequent 

years if tests routinely demonstrate compliance. The commenter asked that the EPA consider 

alternatives that could lessen the financial impact while still ensuring an adequate assurance of 

compliance.
67

Response: The final rule requires PM compliance testing to be conducted on an annual basis to 

show regular compliance with the PM emission limit and to verify the relationship between PM 

concentration in the stack and the PM CPMS monitor milliamp output.

4.6 PM: Request for COMS as a Parametric Monitor

Commenter (0494) suggested that a continuous opacity monitoring system ("COMS") is also a 

monitoring technology sensitive to changes in PM concentrations and can be used to serve the 

same purpose as the PM CEMS as a type of continuous parametric monitoring. The commenter 

noted that the EPA has accepted COMS as an acceptable monitoring approach in previous 

rulemakings and has accepted them as a means of assuring proper operation of PM control 

devices. The commenter stated that using COMS as a continuous parametric monitoring system 

would be more cost-effective and would certainly minimize the impact of this rulemaking on 

this small business.

Response: The EPA disagrees with the commenter in that we hold that a COMS is not sensitive 

enough to distinguish between subtle changes in low level PM concentrations that are necessary 

to allow sources to achieve compliance with an operating limit as required by the rule. There is 

discussion on this topic in the preamble to the rule, Section V. A.1 and in response unit 4.1 

above. 

4.7 PM: Suggested Corrections to PS 11 Issues

Commenter (0523) stated that on February 2, 2012, the commenter documented to EPA its 

concerns with the statistical criteria used in Performance Specification (PS) 11. The commenter 

stated that in that letter, the commenter pointed out that PS 11 requires an emission limit in the 

calculation and the NESHAP final 2010 PM limit was so low that when converted from lb 

PM/ton of clinker to the correct units used in PS 11 it would be somewhere between 3 to 5 

mg/acm depending on the kiln type. The commenter noted that at such low emission limits, the 

statistical performance criterion in PS 11 becomes problematic.

The commenter (0523) suggested two options as correction for the PS 11 issue: (1) increase the 

PM limit so that a PM CEM can be correlated; or (2) redefine the term “emission limit.” The 

commenter discussed how the NESHAP PM limit is a 30-day rolling average, and a facility may 

exceed the NESHAP numeric limit without causing a NESHAP violation. The commenter stated 

that the value that could be entered as the “emission limit” for PS11 is a site-specific number that 

fully captures the range in PM emissions that occur or could occur during a 30-day operating 

period and not the fixed numeric 30-day rolling average limit.
68

Response: Because we are not requiring PS 11 for the PM CEMS, there is no need to address 

this comment. A discussion on the effort and time needed to modify PS 11 can be found in the 

Preamble to the rule, Section V. A.1.

4.8 PM: Inconsistency between Length of Test Runs

Commenter (0523) noted that in the preamble of the proposed rule, PM is based on the average 

of three 2-hour runs at one point and is based on the average of three 1-hour test runs at another 

point. The commenter suggested that the final rule be modified to allow sources the flexibility 

to increase the duration of each run if needed to improve the accuracy of each run. 

Response: The EPA holds that PM emission test runs may be of sufficient duration determined 

by the tester on site to achieve a demonstration of compliance with a standard. While the EPA 

may require minimum sampling times and volumes for sources to demonstrate compliance , we 

will always make allowances for a tester who decides, based on information in the field or from 

past knowledge of the source, decides to collect additional sample volume to show compliance.

4.9 PM: Request for Beta Gauge PM Monitors or Multi Metal CEMS Options for 

Monitoring

One commenter (0504) stated that while they agree with the EPA that light-scattering and lightscintillating PM CEMS are not the appropriate monitoring tool for Portland cement emissions, 

we disagree with the alternate monitoring method, CPMS, suggested in the amendment. The 

commenter suggested the following revisions: 

• Unlike light-scattering or scintillation PM CEMS, beta gauge PM monitors are not 

significantly impacted by changes in PM size and density. Beta attenuation CEMS are 

clearly the more appropriate choice for measuring PM in Portland cement emissions. 

• EPA states in the proposed amendment that no independent standard reference materials 

exist for PM concentrations. This statement is inaccurate, as CES’ Quantitative Aerosol 

Generator (QAG) produces aerosols that are traced to NIST standards. We suggest that 

EPA includes this option for PM CEMS certification in the amended rule. 

• PM is intended to act as a surrogate for HAP metals. There is little to no data suggesting 

that the CPMS approach provides adequate PM data to be considered a surrogate for 

HAP metals. Considering the numerous adverse health effects caused by HAP metals 
69

present in Portland cement emissions, the commenter suggests that multi-metal CEMS 

should be required to provide adequate protection of human health and the environment. 

Response: The EPA does not have, nor has the commenter provided, any data to support the use 

of the QAG as an independent and NIST traceable calibration source for PM CEMS. PM is a 

surrogate for HAP metals in the rule, with the compliance determination predicated on the use of 

Method 5. PM CPMS are continuous qualitative parametric compliance monitors designed to 

provide assurance of adequate emission control operations between compliance tests. 

Comment: Commenter (0517) specifically request that EPA incorporate language in the final 

rule expressly allowing the use of a HAP metal CEMS to continuously monitor HAP metal 

emissions from existing and new sources. The commenter requests that the EPA expressly allow 

Portland cement plants who choose to monitor HAP metal emissions directly be relieved of the 

PM emissions monitoring requirements. The commenter states that the incorporation of this 

type language would give source operators an alternative and some assurance that monitoring 

with a multi-metals CEMS would be acceptable to the EPA. The commenter believes it is also 

likely to encourage the use of multi-metal CEMS on sources, which is beneficial to EPA’s 

understanding of the health effects associated with metal HAP. The commenter also believes 

multi-metal CEMS would provide source operators with more feed-back on control of metals 

and may allow them to optimize operations to minimize HAP metal emissions.

Commenter (0517) believes that the acknowledged difficulties with monitoring PM emissions 

continuously at Portland cement plants undermine one of the chief assumptions behind the 

choice of PM as surrogate (i.e. that PM is easier to monitor than HAP metals). The commenter 

states that there is plenty of evidence that HAP metal CEMS are viable and not difficult to use. 

The commenter noted that one HAP metals CEMS, the Xact, has been used to monitor HAP 

metals for compliance at a hazardous waste incinerator for six years as part of an EPA approved 

Alternative Monitoring Plan and that the procedures used to certify the Xact have been 

recognized by EPA as Other Test Methods and have been published in peer reviewed journals. 

The commenter further states that this same monitor has demonstrated accuracy in measuring 

both mercury and non-mercury HAP metals on several different types of sources including coalfired power plants, coal fired furnaces, and diesel fired incinerators.

Commenter (0517) would like to have either a total HAP metals MACT floor or individual metal 

emissions limits as an alternative to using PM CEMS. The commenter would like the EPA to 

develop either a total HAP metals MACT floor or individual HAP metal emissions limits for 

existing and new Portland cement facilities similar to the rule promulgated for the Electric 

Generating Utilities MACT rule. The commenter states that data gathered during the 1998 rule 

making process could be used to develop this floor. The commenter believes that this gives plant 

operators additional control options and flexibility in achieving emissions limits and that the 

direct monitoring of pollutants rather than a surrogate (PM) will contribute to a better 

understanding of the health effects associated with each metal. The commenter also believes that 
70

having these alternative non-Hg metal emissions standards will contribute to utilization of multimetals CEMS which represent the highest level of monitoring for these sources (i.e. directly 

monitoring the HAP pollutant of concern on a continuous basis).

Response: EPA agrees in principle with the commenter’s position that the direct measurement of 

individual metal HAP would be preferable to measuring PM as a surrogate. However, we do not 

have sufficient metal HAP emissions data nor did the commenter provide data sufficient to allow 

EPA to consider either individual metal HAP limits and monitoring. 

The EPA currently has no performance specification available to certify a Multi-Metals CEMS. 

The MATS rule allows for (and mentions in the preamble) a source to apply for a multi metals 

CEM as an alternative monitoring approach and, if accepted, use of such is approved. In that 

light we are also changing the requirements of the rule to allow for the use of PM CEMS with 

the provision that an alternate monitoring application which specifies a three-hour average 

compliance period be approved. At this time, EPA has no data on the ability of an independent 

standard to certify the accuracy of a PM CEMS or multi-metal CEMS. 

As discussed in section V.A.2 of the preamble to the proposed rule, the EPA allows for the use 

of beta gauge PM monitoring technology as a PM CPMS monitor. The EPA does not see beta 

gauge PM CEMS or multi metals CEMS as a panacea to resolve issues with PS-11, low PM 

concentrations, and variable PM characteristics of portland cement plants that were noted in the 

preamble to the proposed rule. 

4.10 PM: Bag Leak Detection as a Parametric Monitor

One commenter (0506) questioned the need for both a PM CPMS and a bag leak detection 

system.

Commenter (0495) states that as an alternative to the exceedingly expensive particulate matter 

CEMS installation EPA proposes, EPA should allow the installation and operation of bag leak 

detection systems. The bag leak detection system provides ongoing monitoring of the bag house 

component performance and provides for continuous compliance demonstration in a manner 

similar to PM CPMS and at a much lower cost than PM CPMS.

One commenter (0251) stated that it is unclear what kinds of PM CPMS equipment are 

acceptable. Since the proposed rule indicates that PM CPMS output may be expressed as mA, 

stack concentration or other raw data signal, can an existing stack opacity monitor or an in-stack 

bag leak detector system (BLDS) be used as a PM CPMS? The proposed rule has the following 

language: "Current PM CPMS have an operating principle based on in-stack or extractive light 
71

scatter, light scintillation or beta attenuation". Is this intended to mean that only these 

technologies qualify as PM CPMS under this rule?

Response: The proposed rule did not require affected sources to be monitored by both CPMS 

and a bag leak detection system. A CPMS is required on kiln stacks and alkali bypass stacks. A 

BLDS is an option for raw material dryers and finish mills. Where a PM CPMS is required for 

continuous PM monitoring, a BLDS is not required by the rule.

The EPA does not have information that shows BLDS are capable of the sensitivity and stability 

necessary to operate as a PM CPMS. As such, we have not included BLDS in our list of 

available PM CPMS technologies.

4.11 PM: Four CPMS Deviations in 12 Months Does Not Equate to a Violation

Commenter 0495 stated that the presumption that more than four PM CPMS deviations in a 12-

month operation period is a violation of PM standards is unreasonable. The commenter 

indicates that the proposed reconsideration provides that “PM CPMS deviations leading to more 

than four required performance tests in a 12-month process operating period [are] presumed a 

violation of this standard.” 77 Fed. Reg. 42,377. 

The only reason EPA provides for this is that EPA “believe[s]” that there should be few 

deviations from the limit because “the site-specific CPMS limit could represent an emissions 

level higher than the proposed numerical emissions limit since the PM CPMS operating limit 

corresponds to the highest of the three runs collected during the Method 5 performance test [and] 

the PM CPMS operating limit reflects a 30-day average that should represent an actual emissions 

level lower than the three test run numerical emissions limit since variability is mitigated over 

time.”

The commenter states that a belief alone is not a defensible basis for presuming a violation. 

Deviations are not violations, and EPA clearly distinguishes between these events. 77 Fed. Reg. 

42,398 (“A deviation is not always a violation”). If EPA has data showing that a facility 

frequently deviates in ways that lead to emissions increases, EPA would likely not have 

difficulty supporting a violation. Instead, what EPA seeks to do here is skip collecting actual data 

and instead shift the burden of proof to facilities. And the only way for facilities to rebut the 

presumption is with “information about process and control device operations in addition to the 

[test results].” EPA should not shift its burden of evidentiary proof to facilities. EPA should not 

finalize this presumption.

Response: See Preamble section V.A.2. As noted there, first, EPA is not using the term 
72

“deviation” in the final rule, in part because it created the type of confusion reflected in this 

comment. The basis of the rule establishing that four calendar year exceedances of the CPMS 

monitoring limit is presumptively a violation of the emission standard are: a) the CPMS 

measurements show an increase in PM emissions (see response unit 4.1 above); b) the parametric 

limit is established as a 30-day average (rolling), so that short-term increases and decreases will 

be averaged out over the 30-days of measurements (see, e.g. 75 FR 54988/2-3 explaining why 

variability is dampened as the number of measurements increases)6

; c) EPA has built a scaling 

factor into the rule to accommodate those situations where a measured increase in the PM signal 

would not indicate that emissions exceed the level of the stack-based standard.

4.12 PM: Clinker Production Monitoring

Comment: Commenter (0505 - Appendix G) stated PM compliance is based on stack tests. PM 

parametric monitoring does not require hourly clinker production monitoring. The commenter 

recommends that EPA remove “PM” from this sentence in 63.1350(d) to read: If you are subject 

to an emissions limitation on PM or mercury emissions (lb/ton clinker), you must...

Response: The EPA agrees with the commenter in that PM CPMS is based on an operating limit 

and not an emissions limit and has revised the language in 63.1350(d).

4.13 PM: Comment Regarding 63.1343(b)

Comment: Commenter (0505 - Appendix G) asked why can’t the equation in 63.1343(b) (PM 

alt = (0.0060 x 1.65)(Qk + Qg + Qab + Qcm)/7000) just use the flow measured at the main 

stack for the CEMS. The basis for flow determination is not defined. It is unclear how the 

facility-specific PM limit is to be applied (i.e. on a flow capacity basis or on an actual flow 

basis.) If an actual flow basis is used, does the alternate PM need to be periodically revised? 

The issue of flow basis was also asked in Dec 2010, but it was not addressed by EPA. 

Commenter recommends that EPA simplify the equation by just using the total stack flow. Q 

should be main stack flow capacity, not what was measured during the stack test. Update 

equation variable descriptions to read “exhaust flow capacity of...” i.e. Qk = The exhaust flow 

capacity of the kiln (dscf/ton raw feed).

Response: The calculation referenced by the commenter is correct as stands. The requirement in 

this rule section is for combined PM emissions from kilns with an alkali bypass stack and/or 

inline coal mill stack. As such, the flow from each, and apportioned PM concentration from 

each, is included in the calculation. As this is an alternate PM emission limit compliance for 

kilns with these configurations must be demonstrated at each performance test.

 6 What is being averaged are milliamp signals from the CPMS, which are expressed numerically.
73

4.14 PM: Comment Regarding 60.64(b)(1)(ii), 63.1349(b)(1)(i)(B), and 

63.1350(b)(1)

Commenter (0505 - Appendix G) stated that Pg 44 of pre-publication preamble says 2-hr runs. 

They assume that preamble text is a typo. Same in published preamble – see 77 FR 42376, 1st 

column, 2nd paragraph. This comment is in reference to the following requirement: record all 

hourly average output values from the PM CPMS for periods corresponding to the test runs (e.g. 

three 1-hr average PM CPMS output values for three 1-hr test runs). Method 5 tests. 

[60.64(b)(1)(ii), 63.1349(b)(1)(i)(B), and 63.1350(b)(1)]. The commenter recommends that 

EPA allow additional test runs or longer test runs for setting operating parameters like allowed 

for Alternate THC limit. The commenter provided a recommended change to 63.1349(b)(1)(ii).

Response: The EPA requires minimum test volume for PM in places where test runs longer than 

one hour are likely necessary, though we do not require that this is the maximum volume or 

sampling time. We recognize the tester in the field as the ultimate determination of sample 

volume and/or duration as the onus is on them to show detection with the test method, and this is 

generally accomplished with a longer test run. While longer test runs may resolve many 

detection limit issues, an increased number of test runs is not allowable for compliance 

determination which is always based on three test runs.

4.15 PM: Comment Regarding 60.64(b)(1)(iii) and63.1349(b)(1)(i)(C)

Commenter (0505 - Appendix G) asked "whether it is the 1-hr average recorded during a 1-hr 

test run or is it in any 60 consecutive minutes during stack testing (e.g. last 20 minutes during 

run 1 and first 40 minutes during run 2) if they give the highest 1-hr average? If runs longer 

than 1-hour are allowed, then the average CPMS output value for the run should be used. This 

comment is in reference to the following requirement: operating limit is the highest 1-hour 

average PM CPMS output value recorded during the performance test. New limit established 

after each performance test. [60.64(b)(1)(iii) and63.1349(b)(1)(i)(C)]. 

Commenter recommends that EPA change the requirement to the “highest PM CPMS output” 

corresponding for run (regardless of the duration of the run) demonstrating compliance with PM 

standard. Allow testing over range of conditions or PM levels as an option. Provide protection 

from enforcement for a run exceeding the PM limit during test like PM CEMS calibration. The 

commenter recommends that EPA change text to: “Determine your operating limit as the highest 

1-hr average PM CPMS output value corresponding to a test run recorded during the 

performance test.”

Response: The EPA has modified the PM CPMS operating limit procedure in the final rule. The 

source must now use the average of all PM CPMS values recorded that correspond with the three 

compliance test runs when setting their site-specific operating limit. The source must also 
74

correlate these data with the average of all three PM compliance tests, as this is the number 

representing compliance determination.

4.16 PM: Comment Regarding 63.1350(b)(1)(iii)

Commenter (0505 - Appendix G) stated a “deviation” could be a lower value, which may not 

be a concern. What is a “process” operating day? Why not specify that the average is only a 

deviation if it is 10% greater than the limit like is done for the alternate THC limit? 

Commenter recommends that EPA clarify that a deviation only occurs if the 30-day average of 

the operating parameter exceeds the operating limit by 10%. Change text to: (iii) For any 

exceedance of the 30 process operating day PM CPMS average value...

Response: The EPA is not including the term “deviation” in the final rule. Moreover, the EPA 

disagrees with the commenter and is retaining the definition of PM CPMS in the final rule. In 

evaluating PM CPMS the EPA recognizes that this is not an instrument calibrated to known 

standards whereas a THC monitor functioning as a parametric organic HAP monitor with the 

alternate THC standard is operating within a known, calibrated, range. As such, we are 

protective of the emission limit and allow a very limited confidence to operations that would 

carry average measurements above the operating limit. For more discussion of this see the PM 

CPMS scaling discussion in the Preamble, Section V.A. 

4.17 PM: Comment Regarding 63.1350(b)(1)(iv)

Commenter (0505 - Appendix G) stated Pg 51 of the pre-publication preamble says this is 

rebuttable, but the basis for rebuttal is not in the rule." 

Commenter recommends that EPA add basis for rebuttal rule. Add text: The source may rebut 

the presumption that the PM CPMS deviations led to a violation by submitting information about 

process and control device operations in addition to Method 5 performance test results.

Response: EPA is not adding this language to the rule to avoid confusion that this might be the 

only way a source could rebut the presumption. We have, however, added this language to the 

preamble to the final rule as an example of how a source could rebut the presumption. 
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4.18 PM: Comment Regarding 63.1349(b)(1)(ii) and (iv)

Commenter (0505 - Appendix G) stated "Why is there a minimum value? This would support 

longer runs." 

This comment is in reference to the following requirement: use Method 5 for 3 runs under 

highest load or capacity reasonably expected to occur. Min sample vol of 2 dscm for new sources 

and 1 dscm for existing sources. Calculate the average results from the 3 runs. Separate 

performance tests for RM on and RM off. [63.1349(b)(1)(ii) and (iv)]. (Commenter mistakenly 

identified the affected section as 63.1350.)

Commenter recommends that text be changed to “at least three test runs” and allow testing over 

range of conditions or PM levels as option. Include a provision to allow test values above the PM 

limit while establishing parameters for CPMS. Change to “For each performance test, conduct at 

least three separate runs under the conditions...”

Response: The EPA bases compliance with the emission standard on three test runs, but also 

recognizes that sources may wish to assess PM variability during the testing and so we have 

allowed for the use of Method 5I in the final rule, which inherently provides for twice the 

emission data in three test runs. Method 5I specifies dual sample analysis, which provides for 

more emission test data (six data points from three test runs) and thereby provides more 

information with which to characterize emissions variability. Additionally, sources and their 

testers always have the option of conducting longer emission tests if this is needed to resolve 

detection issues.

4.19 PM: Comment Regarding 63.1350(b)(2)

Commenter (0505 - Appendix G) stated that this is confusing – there is no continuous 

determination of an hourly kiln PM emission rate. Deviation from the flow limit could be higher 

or lower than the limit established. Is the deviation a 30-day rolling average? 

This comment is in reference to the following requirement for alkali bypass stack: Continuous 

gas flow measurement and annual Method 5 test. Use emission factor and gas flow to determine 

continuous emissions. Sum with hourly kiln PM emissions to determine 30-day rolling average. 

Or set a maximum gas flow rate for alkali bypass during annual Method 5 test and continuously 

monitor the gas flow rate. If there is a deviation of more than 10% you must retest the kiln and 

bypass. [63.1350(b)(2)].
76

Commenter states that the gas flow rate as an operating parameter is the only way this works. 

Commenter recommended that EPA clarify that a deviation is only if the 30-day average of the 

operating parameter exceeds the operating limit. Allow for 10% exceedance. Change

63.1350(b)(2)(c) to “...If there is a deviation an exceedance of the monitored flow rate...”

Response: The change to PM CPMS monitoring from the main stack requires a change to this 

section, and the rule language has been modified appropriately. Flow apportionment is not 

required to demonstrate compliance with the PM operating limit, though it will be required to 

demonstrate compliance with other pollutant concentrations (e.g. mercury). PM CPMS 

monitoring will demonstrate compliance with an operating limit established during PM 

performance testing of all emission points. The term “deviation” is not used in the final rule.

4.20 Hydrogen Chloride (HCl): General Support for Proposed Standard

One commenter (0505) stated they support EPA‘s proposal not to require continuous 

monitoring for HCl by facilities equipped with dry sorbent control systems.

Two commenters (0475, 0506) supported EPA’s proposal to allow continuous monitoring of 

SO2 as a surrogate for continuous monitoring of HCl control device parameters.

Commenter (0475) also supports EPA’s proposal to allow HCl testing every 30 months to 

confirm the appropriateness of using SO2 monitoring in place of HCl monitoring. The 

commenter also supports the proposed use of the highest 1-hour average recorded during the HCl 

performance test as a surrogate for compliance with the HCl emission standard. 

Response: EPA has noted the commenters’ support for the compliance flexibilities allowed by 

the amendments. 

4.21 HCl: Opposition to HCl CEMS and PS 15 

Two commenters (0505, 0506) stated that EPA should remove references to Performance 

Specification (PS) 15 for continuous monitoring of HCl because it is impractical and will be 

replaced by a more robust contemporary HCl performance specification currently in preliminary 

draft form and still under development by EPA and, in part, the subject of industry field 

evaluations. Considerable additional technical work remains to be done to determine 

appropriate specifications and test procedures, to develop and validate traceable calibration gas 

standards, and to validate HCl CEMS which are still under development and not yet 
77

demonstrated to meet draft specifications. According to the commenter, PS 15 is a generalized 

“FTIR-based” CEMS performance specification and does not include the provisions for 

accurate measurement of HCl and will be replaced by a technology neutral and HCl-specific 

performance specification. According to the commenter, they had submitted comments on PS15 in response to EPA’s previous subpart LLL proposal and attached a copy of those comments 

(Appendix E to these comments) to their current submittal. The commenter presented those 

comments as follows:

1) PS 15 is not workable for the cement industry and EPA concurred with this comment. 

2) EPA is currently working on an HCl Performance Specification (PS-18) that is not 

technology specific. (PS-15 specifies use of FTIR CEMS only.) 

3) Work is being done by both industry and EPA in HCl CEMS evaluations in support of 

this new performance specification. 

a. Prototype and currently available HCl CEMS are being evaluated at cement kilns to 

establish limits of detection for these systems, 

b. Instrument manufacturers of numerous technologies are working on means to 

improve performance for low concentration HCl measurements on a continuous basis, 

c. Sampling system designers are undertaking measures to reduce adverse particulate 

loading effects on HCl measurements, 

d. Gas manufacturers are undertaking means to generate known accuracy low 

concentration gas standards in the absence of NIST Traceable standards, 

e. NIST is expected to begin working on HCl calibration gas standardization,

f. EPA ORD is conducting laboratory studies on HCl CEMs technology and calibration 

standards and these results are to be used in the development of the new EPA HCl 

Performance Specification, 

g. Numerous stakeholder conference calls and meetings have been held to discuss topics 

relevant to HCl continuous monitoring as it applies to the EPA draft performance 
78

specification. 

Response: . EPA did not propose, reconsider, or otherwise reopen the issue of the Performance 

Specification for HCl CEMS in this proceeding. Moreover, PS-15 is based on reference Method 

321 which has been shown to measure accurately over the range of operating conditions and HCl 

concentrations expected for facilities that are in compliance with this standard. However, we 

note that the EPA is on the verge of proposing a technology independent Performance 

Specification for HCl monitoring (which has taken years to develop) which (if finalized) will 

provide facilities with an additional option including the ability to use technologies other than 

FTIR as HCl CEMS. If facilities believe it would be preferable to use an alternative 

monitoring method for the HCl standard, they may submit for approval an alternative test 

method request under 63.7(f) to use an alternative approach to monitoring HCl to demonstrate 

compliance.

Comment: One commenter (0506) stated that if the Agency decides to require these CEMs, 

there is a better interim solution than PS 15. EPA has already approved two preliminary, Other 

Test Methods (OTM) for HCl CEMs. These are posted at www.epa.gov/ttnemc01/prelim.html as 

OTM 22 and 23. The commenter believes that it makes more sense to temporarily use a

preliminary test method already approved for HCl CEMs than to use an already promulgated 

performance specification that may not apply. The commenter suggested that EPA modify the 

final rule to allow the use of OTM 22 and 23 instead of PS 15.

Response: Other Test Methods (OTM 22 and 23) were provided on our website for evaluation 

and/or use by the stakeholder community and to encourage development of field test data 

supporting the procedures described in these methods. Significant improvements and additions 

to these OTM procedures are necessary before they will meet EPA’s HCl CEMS performance 

specification requirements. EPA’s efforts to prepare and distribute a technology neutral 

Performance Specification embraces the key components of OTM 22 and 23. If a facility 

manager believes that there is an alternative procedure that can better meet the HCl compliance 

monitoring requirements in this rule, they always have the option to submit it as an alternative 

test method under 63.7(f) as previously mentioned. 

Comment: One commenter (0505) stated that traceable HCl calibration standards of known 

quality are not available. Currently, there are two gas vendors who produce manufacturercertified HCl standards. No EPA or NIST Traceable standards exist. The lowest available 

concentration levels are 10 ppm as a commercial product with a 5 ppm “under development” 

standard available for special projects. Analysis accuracy of these standards is claimed to be 

±5%. This corresponds to ±0.5 ppm for the 10 ppm calibration gas standard. Clearly this is still 

a problem as the Subpart LLL standard is 3 ppm HCl dry at 7 percent O2. The actual asmeasured concentration on a wet basis and at the stack O2 concentration equivalent to the 

emission standard is about 2 to 2.5 ppm. The uncertainty of the calibration gas standards is the 
79

same as the calibration error and calibration drift specifications for a measurement system with 

a 10 ppm span. The general provisions of Part 63 require adjustment of the monitor when the 

zero or upscale calibration drift exceeds two times the drift limit, which is ±1.0 ppm (about 50 

percent of the Subpart LLL emission limit).

According to the commenter, stakeholder participants have stated that the use of dry compressed 

calibration gases will be unacceptable, due to the length of time such gases must be injected; 

instability in the compressed gas mixtures or adsorption in the regulators and deliver system; and 

because of the strong adsorption of dry HCl mixtures on Teflon tubing followed by desorption 

when wet gas is reintroduced. These phenomena have been observed in field trials. EPA is 

investigating a prototype system that actively humidifies the calibration gas mixtures and is also 

exploring the use of gas generators which create calibration standards from evaporation on 

known liquid solutions and quantitatively dilution similar to systems used by some Hg CEMS to 

produce HgCl2 calibration standards. 

The commenter stated that after the type of calibration standard is determined, along with its 

associated limitations, EPA will either need to develop and publish interim traceability protocols 

or revise the “EPA Traceability Protocol for Assay and Certification of Gaseous Calibration 

Standards,” EPA 600/R-12/531 (May 2012). 

According to the commenter, the above activities will take considerable time and the outcome 

cannot be predicted at this time. HCl CEMS monitoring requirements should be “reserved” until 

(1) reliable calibration standards of know accuracy and precision are available, (2) HCl CEMS 

performance specifications and quality assurance procedures are developed, (3) commercially 

available CEMS are demonstrated to be capable of meeting the requirements, and (4) EPA 

completes rulemaking for these requirements and promulgates appropriate regulations.

Response: EPA recognizes that NIST traceable HCl gas standards are not yet available, but we 

have been coordinating with NIST and the gas vendors as well as working on other options (gas 

generation techniques) to ensure that viable options will be available in time for the compliance 

date. In the interim, facilities can purchase certified gas standards for use in selecting and 

installing monitoring systems. EPA disagrees with the fundamental premise that a facility is 

limited to the maximum error implicit in zero or calibration drift that exceeds two times the drift 

limit. While the general provisions of Part 63 require adjustment of the monitor when the zero or 

upscale calibration drift exceeds two times the drift limit, there is no restriction on more frequent 

zero drift adjustment up to a frequency of once per day. In addition, measurement at ±1.0 ppm is 

on the order of three times lower than the HCl emission standard in Subpart LLL. Therefore, 

even using a 10 ppm calibration standard as the span, measurements are possible significantly 

below the standard; a lower span of 5 ppm would allow for additional accuracy. EPA’s advice to 

facilities concerned with making more accurate measurements below 1 ppm is to identify and use 

the necessary quality and sensitivity in instruments that measure at lower detection limits. 
80

4.22 HCl: Comment on Pending Performance Specifications

One commenter (0505) stated that HCl CEMS Performance Specifications are still under 

development and many technical issues remain to be resolved prior to proposal (expected late 

2012 or early 2013) and promulgation in 2013 or 2014 according to EPA representatives. EPA 

has undertaken a stakeholder participation effort to discuss fundamental issues affecting the 

development of appropriate HCl CEMS performance specifications. The commenter stated that 

EPA has circulated an initial draft and a revised “work in progress draft” (dated April 4, 2012) 

but many issues remain and need to be resolved. The commenter submitted comments in 

response to the most recent draft on April 22, 2012, (see Appendix E to these comments) and 

also met with EPA representatives on May 7, 2012 to discuss the issues and laboratory research 

efforts EPA has planned for the summer 2012 to address some of these issues. 

According to the commenter, one cement company has undertaken a field evaluation involving 

the concurrent testing of four HCl CEMS selected as promising candidates and installed at a 

contemporary cement kiln system, which is still ongoing. These projects are expected to provide 

essential technical insight and resolution of some of the critical issues central to the development 

of HCl CEMS performance specifications. Without the information and insights gained from 

these and other studies, the development of HCl CEMS performance specifications is based 

purely on speculation and the uncorroborated claims of some vendors. Until the work is 

completed, it is not possible to develop achievable technical specifications, performance test 

procedures, or quality assurance procedures.

Response: The subject of this comment is not within the scope of this rulemaking; no response is 

necessary.

4.23 HCl: On-going Quality Assurance Requirements are Premature

One commenter (0505) stated that the requirements for on-going quality assurance of HCl 

CEMS have yet to be developed. According to the commenter, the proposed requirements for 

quality assurance at § 63.1350(l)(1) are a placeholder at the current time, because no draft ongoing QA procedures have been circulated to stakeholders let alone finalized. Because the 

frequency and achievable criteria for on-going HCl monitoring must be based on the 

performance of actual CEMS meeting the performance specification requirements, and in view 

of the fact that these requirements are evolving, it is not yet possible to collect the necessary 

field data to serve as the basis for QA requirements. It is likely that neither Method 321 (nor any 

other test method) can be used for relative accuracy testing because the effluent HCl 

concentrations will be below the “limit of detection” (LOD) of both the test method and the 

installed CEMS. Instead, dramatically different “dynamic spiking” procedures will be needed 

for periodic accuracy assessment for initial certification and on-going QA. Dynamic spiking 

procedures have not been developed and included in any promulgated EPA regulations for any 
81

CEMS under any regulation. 

The commenter stated that EPA‘s request for comments on this provision is therefore premature 

and should be deferred until there is something of substance to review. 

Response: The subject of this comment is not within the scope of this rulemaking; no response 

is necessary.

4.24 HCl: Span Calibration Requirements

One commenter (0505) stated that the proposed HCl CEMS span requirements in 

§63.1350(l)(1)(i) (1) are not appropriate for HCl CEMS, (2) are set at too low a level for 

compressed gas calibration standards, and (3) require revision to avoid confusion in the 

implementation at cement kilns. According to the commenter, the proposed requirements would 

result in a span value of 5 ppm for cement kilns. The span value cannot be lower than 10 ppm 

for any kiln system, otherwise the calibration error, linearity, and calibration drift specifications 

are overly restrictive and unachievable. In addition, compressed calibration standards are 

certainly not available from any supplier to perform linearity tests and cylinder gas audits for 

CEMS with spans less than 10 ppm.

According to the commenter, the proposed requirements are inconsistent with the HCl 

concentrations seen at many cement kilns. Based on area source tests, many kiln systems with inline raw mills have HCl concentrations at or below 1 ppm for mill on operations, and mill off 

HCl concentrations of 5 to 15 ppm. Some kiln systems will be able to comply with a 30-day 

rolling average 3 ppm HCl concentration with mill off HCl concentrations approaching 30 ppm. 

HCl CEMS will need to quantify accurately HCl concentrations at both high and low levels. It 

may become necessary to apply different accuracy, calibration error, and drift specifications for 

the high and low levels. In current preliminary drafts, EPA has simply chosen to specify these 

parameters as a “percentage of span.” This may need to be replaced by tolerances that vary with 

concentration and also provide an absolute specification (e.g., ± 0.5 ppm) for low levels. 

Preliminary work at some kilns suggests that HCl measurement range of 0-30 ppm HCl is 

appropriate. 

Further, the phrase “approximately two times the emissions standard,” as used in the cited 

regulatory text, is confusing and should be changed to say “concentration equivalent to the 

emission standard.” The procedure to calculate this value must take into account the 

measurement basis of the CEMS, the average or typical effluent moisture content, and the 

average or typical oxygen concentration. If EPA does not provide guidance for the selection of 

these values, then it should be sufficient that the source operators use their own judgment and 

that assumptions and calculations are documented in site-specific monitoring plans and 
82

associated records.

Response: EPA appreciates the comment that the CEMS span and uncertainties of the data at 

low concentrations are interrelated and a limiting factor for measurement accuracy. However we 

disagree with the commenter’s conclusion. As previously noted, EPA acknowledges that NIST 

traceable HCl gas standards are not yet available, but we have been coordinating with NIST and 

the gas vendors as well as working on other options (gas generation techniques) to ensure that 

viable options will be available in time for the compliance date. We also know that gas vendors 

are working to provide qualified gas standards at lower concentrations at least down to 2ppm. 

Ongoing QC requirements in our performance specifications allow a zero drift of 10% of span 

before data are invalidated. CEMS operating at 10 ppm span should be able to measure 

accurately down to an HCl gas concentration of approximately 1 ppm, which is approximately 

one third of the emission limit. At 5 ppm span an HCl CEMS system is able to quantify HCl gas 

concentration down to 0.5 ppm which corresponds to approximately one sixth of the emission 

limit. As previously explained, EPA does not agree that a facility must always be limited by the 

maximum error allowed by calibration drift specifications, as drift may be adjusted up to once 

per day.

EPA has designed the HCl CEMS span requirements such that measurements during normal 

“mill on” operations will typically be made within the limits of the span while much of the “mill 

off” operations measurements will be ‘above span’. The traditional span-based accuracy, 

calibration error, and drift specifications will serve to quality assure the within span 

measurements while the ‘above span calibration’ requirements developed for this rule will serve 

to quality assure the measurements made ‘above span’. 

EPA agrees with the commenter regarding the wording of the paragraph specifying the HCl 

CEMS span and has added language saying “.....concentration equivalent to....the emissions 

standard...” as well as clarified that engineering judgment may be used in determining the span 

and that related assumptions and calculations must be documented in site-specific monitoring 

plans and associated records.

4.25 HCl: Above Span Calibration Requirements

One commenter (0505) stated that the proposed Subpart LLL “above span” HCl CEMS QA 

requirements and three options presented in §63.1350(l)(1)(ii) (A), (B) and (C) are not 

appropriate and should be substantially revised. These sections are simply a repetition of the 

similar, new proposed requirements for Hg CEMS, but are not applicable to HCl. Hg CEMS 

systems that have been demonstrated to meet PS12A requirements (e.g., Thermo and Tekran 

models) are both dilution extractive systems and both have analysis systems which have been 

demonstrated to be linear over very wide analytical ranges. These Hg CEMS are also operated 

on elemental Hg calibration gas generators and either evaporative oxidized gas generators or 

special systems that quantitatively convert elemental Hg to oxidized Hg. The elemental Hg 

generators are believed (but not yet demonstrated) to have the dynamic range capability and 
83

flexibility to do the normal level calibration checks and the “above span calibration checks.” 

However, the above characteristics of the Hg CEMS and their associated calibration gas 

generators are not applicable to HCl CEMS which utilize very different technologies and suffer 

different challenges. 

There is no technical basis to believe that HCl CEMS could meet the proposed requirements, and 

will likely not provide data of known quality if challenged using the proposed above span 

calibration requirements. 

HCl CEMS will need to quantify accurately HCl concentrations at both high and low levels in 

order to monitor compliance with the HCl standard and the site-specific measurement range will 

need to be determined to include all concentrations that will be encountered. The constraints on 

measurement range, and specification of “span value” should not make this more complicated or 

difficult. In addition, the traditional concept of measurement range based on analog outputs is 

obsolete. It should be understood that the measurement range of most FTIR analyzers and other 

sophisticated measurement devices is dependent on the fundamental design. Regardless of any 

regulatory specification, this does not change. The sensitivity, resolution, and limitation of 

detection of these systems are unaffected by external regulatory specifications, provided that data 

are acquired digitally from these measurement systems (rather than through analog outputs such 

as 4-20 ma circuits.) 

EPA‘s proposal of the “above span” HCl CEMS QA requirements is premature, lacks credible 

basis, cannot be demonstrated and should be withdrawn until relevant technical investigations 

are completed. HCl CEMS monitoring requirements should be “reserved” until (1) reliable 

calibration standards of know accuracy and precision are available, (2) HCl CEMS performance 

specifications and quality assurance procedures are developed, (3) commercially available 

CEMS are demonstrated to be capable of meeting the requirements, and (4) EPA completes 

rulemaking for these requirements and promulgates appropriate regulations.

Response: The EPA disagrees with the commenter’s contention that HCl CEMS measurements 

of standard concentrations do not respond in a linear way similar to Hg CEMS measurement 

technologies. There is no technical basis to believe that HCl CEMS could not meet the 

requirements and will likely not provide data of known quality if challenged using the proposed 

‘above span’ calibration requirements. The optical technologies that are being employed in the 

commercially available HCl CEMS that we are seeing are based on fundamental spectroscopic 

laws that support a linear response to HCl concentration. Standard optical spectra over a range 

of concentrations responsive to this standard are available that should be used to confirm the 

performance of a HCl CEMS. In responding to the comments regarding the ‘above span’

calibration requirements for Hg CEMS, the EPA developed simpler, more flexible requirements 

to accomplish ‘above span’ calibrations that are also applicable to HCl CEMS. These revised 

requirements allow for the ‘above span’ calibrations to be conducted either before or following 

‘above span’ measurements and offer wide latitude in calibration gas levels (50 to 150 percent of 
84

measured value) such that facilities can reasonably be expected to have calibration gases at 

appropriate levels on hand. The commenters concerns with availability of reliable calibration 

standards of known accuracy and precision and new HCl CEMS performance specifications and 

quality assurance procedures are addressed in prior response to comments. 

4.26 HCl: Opposition to Elimination of CEMs for Dry Scrubbers

One commenter (0508) stated that EPA’s rationale for allowing sources using wet scrubbers to 

comply with the HCl standards via periodic compliance tests rather than CEMs was that wet 

scrubbers are so efficient that that periodic monitoring rather than CEMS provide sufficient 

assurance of compliance. The commenter stated that dry scrubbers, however, are less efficient 

that wet scrubbers. EPA does not claim that they provide the sufficient assurance of compliance 

such that CEMS are not necessary. Indeed, sources equipped with dry scrubbers could 

nonetheless violate standards depending on whether the scrubbers are being operated efficiently 

and what the input of chlorine to the kiln is.

Response: The EPA disagrees with the commenter’s statement that dry scrubbers are not 

sufficiently efficient to assure that sources are in compliance with the HCl limits. As shown at 

proposal, dry scrubbers typically operate at greater than 95 percent removal efficiency. Coupled 

with the requirement to continuously monitor lime injection rates, we believe allowing sources 

equipped with dry scrubbers to use periodic performance test and parametric monitoring is an 

appropriate option to an HCl CEMS. Furthermore, there will be continuous parametric 

monitoring associated with the standard (in the form of SO2 monitoring, or (as just noted) 

monitoring of lime injection rate) so that there will in fact be continuous assurance that the 

scrubber system is operating efficiently at all times. 

4.27 HCl: Opposition to SO2 CEMS

One commenter (0508) stated that EPA’s proposal to allow plants to use SO2 CEMS instead of 

showing compliance with the HCl standard is unlawful. EPA must set standards for each 

hazardous air pollutant that cement plants emit, and cannot meet that obligation by setting 

standards for other pollutants instead, unless the agency establishes a valid surrogacy 

relationship. 

The commenter stated that EPA’s claim that “pilot scale tests” support the use of SO2 as a 

surrogate where wet or dry scrubbers are used is not relevant to the test for a valid surrogate. 

Indeed, EPA does not even mention the established test for demonstrating a valid surrogacy 

relationship, far less show that it has been met. In particular, EPA does not claim that HCl is 

invariably present in SO2, not that the agency could make any such claim, which would be 

obviously false. Likewise, EPA does not claim that methods to reduce SO2 are the only means of 
85

reducing HCl, which can be reduced through the use of fuels and feed materials with lower 

chlorine levels as well as the use of control technologies that reduce SO2 emissions. 

Accordingly, any claim that SO2 is a valid surrogate for HCl would be unlawful and arbitrary. 

The commenter stated that EPA would allow plants to set SO2 CEMS levels at “the highest 1 

hour average recorded during the HCl performance test” effectively making that SO2 level the 

source’s only compliance obligation with respect to HCl. Even if the source subsequently stayed 

below that SO2 level, it would not necessarily comply with the HCl standard. First, because the 

“highest” recorded HCl level during a compliance test would not necessarily comply with the 

HCl standard, EPA is effectively proposing to allow sources to meet an SO2 standard that is less 

stringent than the promulgated HCl standard. Thus, EPA is effectively proposing to allow 

sources to exceed emission standards that were set at the statutory minimum stringency. Second, 

even if the “highest” HCl level were below the standard, a source could subsequently operate in 

compliance with the associated SO2 level but out of compliance with the HCl standard if, for 

example, the level of chlorine in a source’s fuel or feed increased.

Response: As we stated at proposal, the use of SO2 CEMS is not intended to demonstrate 

compliance with the HCl limit. Rather, by establishing an SO2 level during an HCl performance 

test and then monitoring SO2 continuously, the source can demonstrate that the wet or dry 

scrubber is performing properly. Thus, SO2 is a monitored parameter to assure proper scrubber 

operation (see previous comment response). 

4.28 HCl: Comment Regarding Part 63 Appendix A

Commenter (0505 - Appendix G) stated that EPA has not provided a definition of how to 

calculate or a procedure to determine the quantification range, particularly in the presence of 

water vapor and as effected by the sampling train/PM filter. This was asked in Dec 2010 and not 

addressed by EPA. Current field test project by industry and lab studies by EPA should result in 

procedure for honest determination of Limitation of Detection for both Method 321 and HCl 

CEMS. Otherwise EPA will revert to revised Method 301 definitions. EPA should use ASTM 

methodology.

This comment is in reference to the following requirement: EPA has specified a “typical lower 

quantification range” of 0.1 – 1 ppm for Method 321. [Part 63 Appendix A] 

Commenter recommends that EPA delete “typical lower quantification range, revise Method 321 

and include DL and PQL determination procedures, performance based.

Response: The EPA plans to include an LOD procedure in proposal of PS 18 and will make note 

to consider a performance based approach to LOD/MDL in future revisions to M321.
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4.29 HCl: Comment Regarding 63.1349(b)(6)(i)(B) and 63.1350(1)(2) and (m)(5)(7) and 

(8)

Commenter (0505 - Appendix G) asked they are to measure and record the parameters for the 

24-hour day on which the three 1-hour tests were conducted. For sorbent, it says 24-hr average 

injection rate and average injection rate for each sampling run.

Wet scrubbers are high maintenance equipment and instrumentation reliability is an ongoing 

issue due to exposure to the slurry chemistry environment.

Flow rate monitors: Compliance should be achievable with routine QA/QC and PM practices

Differential pressure: Maintenance/reliability will be an ongoing issue due to the slurry 

chemistry environment; abnormal differential pressure variances will likely occur from nozzle 

port build-up and daily maintenance and cleaning of the injection nozzles.

PH Monitor: Appliance should be achievable with QA/QC and PM practices – Consider a 

density monitor as an alternative to a PH meter. In general, the SO2 CEMS is a better alternative 

to sustain compliance versus the wet scrubber CPMS method.”

This comment is in reference to the following requirement: for wet scrubber or tray tower 

measure/record pressure drop and/or liquid flow rate and pH in intervals of no more than 15 

minutes during the HCl test. Compute and record the 24-hour average pressure drop, pH and 

average scrubber water flow rate for each sampling run in which the applicable emission limit is 

met. For a dry scrubber measure/record sorbent injection rate in intervals of no more than 15 

minutes during the HCl test. Compute and record the 24-hour average sorbent injection rate and 

average sorbent injection rate for each sampling run in which the applicable emission limit is 

met. [ 63.1349(b)(6)(i)(B) and 63.1350(1)(2) and (m)(5)(7) and (8)]

Commenter asks EPA to clarify how the operating limits are set for a wet or dry scrubber. 

Fix reference in 63.1350(l)(2); (m)(8) does not exist – should be (m)(9), (m)(5) and (m)(7) 

should be (m)(5) through (m)(7).

Change parameter measurement period to only during the 1-hour tests.
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General comments 63.1349(b)(6)(i)(B): B) You must establish site specific parameter limits by 

using the CPMS required in 63.1350(l)(1). For a wet scrubber or tray tower, measure and record 

the pressure drop across the scrubber and/or effluent flow rate and pH in intervals of no more 

than 15 minutes during the HCl test. Compute and record the 24-hr average pressure drop, pH, 

and average scrubber effluent liquid water flow rate for each sampling run in which the 

applicable emissions limit is set. For a dry scrubber, measure and record the sorbent injection 

rate in intervals of no more than 15 minutes during the HCl test. Compute and record the 24-hr 

average sorbent injection rate and average sorbent injection rate for each sampling run in which 

the applicable emissions limit is met.

Response: We agree with the commenter that (m)(8) should be (m)(9) and we have revised the 

rule accordingly. Regarding wet scrubber monitoring requirements, we have not opened the 

provisions of the rule covering wet scrubber parameter monitoring to reconsideration and 

therefore are not revising them. However, the operating limits are listed in Section 1349(b)(6)(i) 

and we believe this language has provided adequate guidance on establishing operational 

parametric limits for wet and dry scrubbers.

4.30 HCl: Comment Regarding 63.1348(a)(6)(iv), 63.1349(b)(6)(iii), and 63.1350(1)(3)

Commenter (0505 - Appendix G) asked "Is it the 1-hr average recorded during a 1-hr test run or 

is it any 60 consecutive minutes during stack testing (e.g. last 20 min during run 1 and first 40 

minutes during run 2) if they give the highest 1-hr average? Is the exceedance of the 1-hr limit 

and SO2 reading above the limit or a 1-hr average reading above the limit or a 30-day rolling 

average above the limit?" 

This comment is in reference to the following requirement: for wet/dry scrubber as an alternative 

to setting scrubber parameters, establish an operating level based on an SO2 CEMS. The 

operating limit will be the highest 1-hr average recorded during the HCl stack test. If the 1-hr 

operating limit is exceeded, must; within 48 hours conduct an inspection and take corrective 

action to return the SO2 emissions to within the operating limit; within 60 days (or normal re-test 

date if earlier) conduct another HCl stack test and re-establish the SO2 CEMS operating limit. 

[63.1348(a)(6)(iv), 63.1349(b)(6)(iii), and 63.1350(1)(3)] 

Commenter states that operating limits should be highest value recorded for any 60 minute 

period during the test and compliance should be based on a 30-day rolling average exceeding the 

operating limit. Change 63.1349(b)(6)(iii): You must establish an SO2 operating limit equal to 

the highest 1-hour average corresponding to a test run recorded during the HCl stack test. 

Change 63.1350(l)(3):...If the 30-day rolling average SO2 levels increase above the 1-hour 

average SO2 operating limit established during your performance test, you must...
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Response: We have changed the procedure for setting the SO2 parameter to the average of the 

SO2 emissions measured during the entire test period. Exceedance of that parametric limit

occurs if the 30 day rolling average of the SO2 emissions exceeds the operating limit. Therefore 

the comment above is moot.

Mercury (Hg): Span Value Requirements

One commenter (0505) stated that changes to the Hg CEMS span value requirements may be 

unnecessarily restrictive for some cement kiln systems. Further clarification of the associated 

calculation procedures is needed to avoid confusion in the implementation of these 

requirements. The commenter compared the currently proposed §63.1350(k)(1) with the 

previous promulgated language . 

The commenter stated that first, the previous language on span included the phrase “at least” and 

thus, was a specification of the minimum span value. This is now replaced by a prescriptive 

requirement. In addition, the previous language required that the span value include the upper 

limit of the mercury measurement range during normal operation. For kiln systems with variable 

Hg concentrations during mill on operation (and kiln systems without in-line raw mills) the new 

wording is potentially overly restrictive and inflexible for some sources. 

For the reasons discussed above, the commenter stated that they believe the foregoing text needs 

to be revised to add the suggested the language show in bold underlined: 

(1) The span value for any Hg CEMS must include the intended upper limit of the mercury 

concentration measurement range during normal ―mill on‖ operation which may be exceeded 

during ―mill off‖ operation or other short term conditions lasting less than 24 consecutive kiln 

operating hours. However, the span should be at least equivalent to You must use a span value 

for any Hg CEMS that represents the mercury concentration corresponding to approximately two 

times the emissions standard and it may be rounded to the nearest multiple of 10 5 μg/m3 of total 

mercury or higher level if necessary to include Hg concentrations which occur (excluding 

concentrations during in-line raw “mill off” operation). As specified in PS 12A, Section 6.1.1, 

the data recorder output range must include the full range of expected Hg concentration values 

which would include those expected during “mill off” conditions. 

The revisions that the commenter proposed would address this, without undermining the 

objective EPA is seeking to achieve. 

The language currently being proposed includes the phrase “at least” and thus was a specification 

of the minimum span value. The text would also require that the span value include the upper 
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limit of the mercury measurement range during normal operation. For kiln systems with variable 

Hg concentrations during mill on operation (and kiln systems without in-line raw mills) the new 

wording is potentially, and unnecessarily, too restrictive for some sources. The revisions the 

commenter has proposed be made to text of this section would address this, without undermining 

the objective EPA is seeking to achieve. 

The commenter stated that second, it is assumed that the concentration equivalent to the emission 

standard is determined on an “as measured basis.” In other words, that the concentration 

equivalent to the emission standard is determined on a wet basis for Hg CEMS providing wet 

basis measurements (including all dilution measurement systems), and is determined on a dry 

basis for Hg CEMS providing dry basis measurements. 

The commenter stated that third, values for the “normal,” “typical,” or “maximum/minimum” 

clinker production rate, effluent flow rate, and in some cases effluent moisture content are 

needed for the calculation of the concentration equivalent to the emission standard. If EPA does 

not provide guidance for the selection of these values, EPA should make clear that it is 

appropriate for the source operator to use his/her own judgment and that assumptions and 

calculations be documented in site-specific monitoring plans and associated records.

Response: We agree with the commenter and revised proposed 63.1350(k)(1) so that the final 

rule reflects the commenter’s suggestion. We also agree that the assumptions and calculations 

needed to determine a mercury concentration corresponding to the emissions standard and other 

best engineering judgments necessary to set up the mercury monitoring systems should be 

documented in site-specific monitoring plans and associated records, which is reflected in the 

final rule.

4.31 Hg: Opposition to Quality Assurance of Hg CEMS Data (Options 1 and 2)

One commenter (0505) stated that two of the options for quality assurance of Hg CEMS data 

for periods when the span value is exceeded may substantially increase apparent monitor 

downtime. Also, the different options are inconsistent as to the level of the daily ‘above span” 

calibration check and impose different acceptance criteria. Proposed §§ 63.1350(k)(2)(i) and (ii) 

provide options where a daily upscale calibration check at a “above span” high level is needed. 

Under Option 1, the high level upscale check would define the measurement range because 

Performance Specification 12A, Section 7.1.3 requires that the high level value be 80 percent to 

100 percent of the “span values” and requires that this value be greater than any Hg 

concentration that is expected to be encountered. If actual concentrations exceed expectations, it 

would therefore be necessary to re-span the CEMS and perhaps repeat part or all of the 

certification tests.
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Under Option 2, the high level upscale check is required to be between 50 percent and 85 percent 

of the highest hourly Hg concentration expected during mill off operation. 

For Option 1, the PS12A requirements and Appendix F, Procedure 5 requirements would apply 

and thus for the daily above span high level calibrations:

• Results exceeding ± 5% of high range span would exceed the elemental Hg 

measurement error specification or results exceeding ±10% of high range span would 

exceed the oxidized measurement error specification in PS 12A; 

• Results exceeding ± 5% of high range span would exceed the 7-day calibration drift 

specification in PS12A; 

• Results exceeding ±10% of the high range span value would require adjustment to the 

monitor in Procedure 5; 

• Results exceeding ±10% of the high range span value for five consecutive days or 

results exceeding ±20% on any day would render the Hg CEMS out of control (data 

invalid and monitor down time) according to Procedure 5. 

In contrast for Option 2, the above span calibration acceptance tolerance is ±20 percent of the 

certified gas concentration. The criteria for when an adjustment of the monitor is required (or 

would be needed) is not clear. It might be interpreted as ±(2x 20%) = ±40% of the certified gas 

concentration. Additionally, the time required to perform the above span high level upscale 

checks may be substantially longer than the time required for the routine daily calibration check 

at the normal concentrations. Additional time may also be required for the calibration gas 

generator to reach equilibrium, for the monitor to reach equilibrium at concentration much higher 

than normal operation (i.e., greater than 50 times the mill on concentration for some sources), to 

measure a stable response, and/or for the system to recover and accurately measure low level 

concentrations devoid of residual Hg from the high level calibration. This could certainly 

invalidate one hour of monitoring data each day. Because time spent performing QA activities is 

considered monitor downtime for EPA reporting purposes, the loss of one-hour each day would 

reduce monitor availability to 95.8 percent before considering any other QA activities or 

monitoring issues. Achieving less than 90 percent monitor availability triggers special additional 

reporting (see § 63.1354(b)(10)) and could trigger enforcement actions in accordance with EPA 

and/or state CEMS enforcement policies. Accordingly the commenter believes that, the proposed 

rule as currently creates a strong disincentive for sources to select either Option 1 or 2. 

Furthermore, Option 1 would require additional calibration error and linearity checks for the 
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initial certification and quarterly calibration gas audits for both elemental and oxidized Hg, 

thereby creating additional opportunities to fail to meet requirements and render the monitoring 

system “out-of-control,” again increasing downtime and reporting. 

Finally, it is not apparent why EPA selected the “50 and 85% of the highest hourly Hg 

concentration expected during mill off operation” for the high range target under Option 2. 

Perhaps this is because choosing a higher value in conjunction with the allowed tolerance of ±20 

percent of the certified gas concentration leads to a very loose requirement such that the 

monitoring data cannot be considered to have any reasonable level of known quality. 

Nevertheless, calibration checks up to 100 percent or perhaps even 120 percent of the highest 

hour Hg concentration should be allowed as the CEMS operator cannot forecast the actual 

concentrations that will be encountered. Based on limited available data at this time, we have 

observed variable “peak” Hg concentrations from one planned raw mill maintenance outage to 

the next at the same kiln system. The reasons for this are not known, but are expected to be sitespecific. Until much more experience is gained, it will be difficult for Hg CEMS operators at 

cement plants to predict what concentration will be encountered during the “highest hour.”

If retained, Options 1 and 2 must both be revised to be consistent with each other regarding level 

of the check and acceptance criteria, and both options must apply the same explicit adjustment 

criteria.

Response: EPA notes that the second option for quality assuring Hg CEMS data when the span 

value is exceeded was provided in the rule for cases where a facility did not want to use a dual 

range Hg CEMS, but did desire to conduct daily 'above the span' calibration checks in 

anticipation of 'above the span' measurements, such as mill off operation or upsets. After 

considering the commenter’s concern with downtime caused by not meeting the calibration 

check acceptance criteria, we have combined the second option with the third option [i.e., 

63.1350(k)(1)(ii) with 63.1350(k)(1)(iii) in the proposed rule] in the final rule . This revision 

allows above the span' calibration checks both in anticipation of and following 'above the span' 

measurements. The revised approach incorporates a normalization equation for cases where the 

calibration check acceptance criteria is not met, eliminating invalidated data and the resulting 

downtime. In combining these Options 2 and 3, we have aligned the acceptance criteria between 

the two options and expanded the criteria for the ‘above span’ calibration gas from 50 to 85% to 

50 to 150% of the highest hourly concentration measured during the period of measurements 

above span. Option 1 to use a dual span monitoring approach remains for those facilities that 

may choose to use it.

4.32 Hg: Opposition to Cycle Time Test

Commenter (0517) states that as part of 40 CFR Parts 60 and 63 the EPA has required a cycle 

time test which specifies a CEMS response time to zero and upscale mercury standards. The 

proposed cycle time test criteria stipulates that the CEMS must reach a reading that is stable and 
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95% of the spiked concentration within fifteen minutes. The commenter strongly objects to the 

promulgating of this requirement for the following reasons: 

1. The Cycle Time test unfairly excludes technologies that can provide accurate mercury 

measurement. 

2. It is inconsistent with already promulgated mercury performance specifications.

3. It is inconsistent with other monitoring techniques that are explicitly allowed by the 

proposed rule.

4. There are no health benefits associated with highly time resolved monitoring of 

mercury. 

5. EPA–HQ–OAR–2009–0234 NESHAP and EPA–HQ–OAR– 2011–0044 removed the 

HG CEMS cycle time requirement. 

Response: The EPA agrees with the commenter and has modified the rule language to not 

exclude technologies that can provide an analytical reading every fifteen minutes.

4.33 Hg: Modification to Quality Assurance of Hg CEMS Data (Option 3)

One commenter (0505) stated that kiln systems where planned mill off periods are typically 

weekly, it is expected that most or all operators will choose Option 3 (Section 63.1350(k)(2(iii)) 

for quality assurance of Hg CEMS data for periods when the span value is exceeded. The 

commenter agrees with the provisions EPA has included for this Option because their 

application does not result in invalidation of data. Some minor modifications to the proposed 

approach may nonetheless be needed to accommodate practical limitations. 

It seems that the proposed approach could be implemented for Thermo and Tekran Hg CEMS 

and their associated certified Hg calibration gas generators and perhaps other Hg monitoring 

systems when they have certified calibration gas generators. However, actual field evaluations of 

these procedures have not been performed at cement kilns or other sources. The technical basis 

for these requirements has also not been subject to (a) the laboratory and field evaluation that 

was conducted for Hg CEMS nor (b) the subsequent technical evaluations and field studies that 

were performed during the development of the EPA Interim Traceability Protocols for Elemental 
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and Oxidized Hg Gas Generators. Because it is not possible to conduct the necessary technical 

evaluations during the compressed comment period, the commenter requests that EPA accept 

further comment on these procedures beyond the comment period as information becomes 

available from actual Hg CEMS installations over the next six months or longer period as the 

procedures have not been attempted by EPA or Hg CEMS vendors. 

Additionally, the commenter believes it is necessary to extend the trigger from “Any time the 

one hour average measured concentration of Hg exceeds the span value you must...” to 2 

consecutive hour averages or any two one-hour clock averages during a 24 hour period in order 

to recognize and therefore accommodate the potential for brief transient emissions to occur 

during a short mill outage or multiple short mill outages such as those caused when the feed silos 

are full. In any case, the “above span” upscale calibration check should never be required more 

than once per day, regardless of whether there is one or multiple periods of elevated emissions 

exceeding the span value. 

The commenter supports the simple mathematical adjustment of data in those cases where the Hg 

CEMS response differs from the certified gas concentration by more than 20 percent. Any 

adjustments that are attempted for the “above span” high level check would detract from the 

accuracy of the measurement data that is acquired for the 85-90 percent of operating hours under 

“normal conditions” (e.g., in line raw mill on). Thus, normalization of the data by applying a 

simple correction factor using the equation provided by EPA appears to be the only option. 

The last sentence of § 63.1350(k)(2(iii) explains that the correction (when applicable) applies to 

all one-hour averages preceding the “above span” calibration. For planned raw mill maintenance 

outages, it is likely that the plant personnel will perform the above span calibration during the 

raw mill down period while the elevated emissions are present. From a CEMS perspective, this is 

good practice because the emissions are elevated during this period and much less time will be 

required for the Hg CEMS to stabilize at the high concentration for the check and less time will 

be required for the Hg CEMS to recover and provide accurate measurements at the elevated 

effluent concentration. In addition, it is appropriate to perform a calibration check, which may 

result in application of a mathematical correction factor contemporaneously with the 

measurement data that will be adjusted. If a problem is discovered, corrective action can then be 

initiated sooner. Also, from a management perspective, scheduling and performing the above 

span Hg calibration check to occur during a planned mill off maintenance period associates 

related kiln operating conditions and related tasks requiring scarce personnel resources, even 

though it adds another task to a complex process. The commenter recommends the text of § 

63.1350(k)(2(iii) be revised in relevant part as follows to address this: 

If the value measured by the Hg CEMS exceeds 20 percent of the certified value of the reference 

gas, then you must normalize the one-hour average stack gas values measured above the span 

during the 24-hour period preceding associated with (i.e., preceding or following) the ‘above 

span‘ calibration for reporting based on the Hg CEMS response to the reference gas as follows:
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Response: We believe that both suggested changes to the language of 63.1350(k)(1)(iii) have 

merit, particularly in light of our combining the second and third options and we have modified 

the rule language accordingly. 

Hg: Use of Method 30B for Alkali Bypass or Coal Mill Stacks

One commenter (0505) stated that the procedures for quantification of Hg emitted from alkali 

bypass or coal mill stacks should allow the use of Method 30B in addition to Method 29. 

Section 63.1350(k)(5(ii) should be changed to allow the use of EPA Method 30B for 

measurement of Hg concentrations in the alkali bypass, coal mill, and any other effluent stream 

with characteristics consistent with the application of Method 30B. Method 30B has been 

demonstrated during numerous field studies at cement plants to provide highly accurate and 

precise measurement data. Method 30B results are equivalent to or better than Method 29 for 

mercury. Method 30B also includes provisions to determine precision (duplicate trains) and 

accuracy (spike recovery) which cannot be provided by EPA Method 29. Method 30B is also far 

less costly than Method 29 and can be performed with either on-site analysis for fast turnaround or using an off-site laboratory. Method 30B samples can be easily and safely shipped 

and analysis of the samples does not require dangerous chemicals and solvents. In contrast, 

Method 29 including its mercury analysis, requires the transport and use of dangerous 

chemicals, exposes test personnel to hazards, the shipments of samples are severely constrained 

by dangerous goods regulations (especially air freight), and requires a lengthy period for sample 

analysis. The performance of Method 29 also results in the generation of a large amount of 

hazardous chemical waste.

Response: The EPA agrees with the commenter and has modified the rule language to allow 

mercury testing using EPA Method 30B.

4.34 Hg: Request to Monitor Upstream or Downstream of a Coal Mill Receiving 

Kiln Exhaust

One commenter (0511) stated that the final rule should enable sources the option to monitor 

mercury in the same manner that they monitor THC and HCl. The commenter requests that EPA 

revise the proposal to allow affected sources the option to monitor (by periodic stack test) 

mercury upstream or downstream of a coal mill receiving kiln exhaust.

The commenter recognizes that the potential exists if it monitors mercury at the inlet to the coal 

mill to double-count some mercury. However, our research shows that this is unlikely to be 

material and that the benefits of monitoring all three pollutants in one location outweigh the 

minimal penalty associated with double-counting of mercury reintroduced into the kiln. 

Therefore, the commenter believes it is appropriate for EPA to allow affected sources that are 
95

willing to accept that there may be some double-counting of mercury to choose where they 

prefer to monitor mercury and states that it is more cost-effective and more robust to monitor all 

three pollutants at the same point.

Response: As the commenter states, conducting mercury stack test upstream of the coal mill 

could result in double counting mercury emissions because mercury may be removed from the 

kiln exhaust gas stream in the coal mill and then released when the coal is injected into the kiln 

for combustion. The mercury measured upstream of the coal mill will also be measured in the 

kiln stack exhaust. The commenter believes, however, that the advantage of measuring all three 

pollutants at the same point outweighs the risk of double counting the mercury emissions. EPA 

has considered the commenter’s request and the final rule allows periodic stack test to be 

conducted either upstream or downstream of the coal mill.

4.35 Hg: Request that Emissions During D/F Temperature Parameter Tests are 

not Considered “Normal Operations”

Commenter (0511) stated that EPA should clarify that mercury emissions that occur while 

affected sources are performing the periodic testing required for D/F are not a part of normal 

operation. Under the D/F portion of the rule, an affected source must re-establish its temperature 

parameter every 30 months or whenever the affected source plans to undertake a change in 

operations that might adversely affect compliance with the D/F standard. Because the limit is 

based on the average of the test run averages, it is necessary to operate the baghouse at elevated 

temperatures during the test runs to achieve operational flexibility. The commenter’s experience 

with monitoring mercury emissions indicates that increased baghouse temperatures result in 

increased mercury emissions. Therefore, this 30-month test does not represent normal 

operations. The commenter also believes it is environmentally counter-productive given the 

years of operation under Subpart LLL and the extensive documentation of kiln compliance with 

the D/F standard. The commenter included a table that illustrates that the Durkee kiln has 

demonstrated multiple times since 2002 that the D/F emissions are at least one order of 

magnitude below the limit. 

The commenter request that the final rule reflect that emissions during these D/F temperature 

parameter tests are not considered “normal operations.” 

Response The commenter has not indicated the magnitude of the mercury emissions variations 

during D/F testing, and we have no indication that mercury emissions would rise in every D/F 

testing instance, or that mercury variability would be any different than during normal 

operations. In addition, there is no requirement that temperature needs to be increased during 

D/F testing. This is a decision made by the source in order to have a higher temperature 

operating limit. We see no reason to excuse mercury emissions during this period. In addition, 

we have no indication that these increases (if they occur) over such a short period of time would 
96

significntly affect the 30-day average. 

4.36 Hg: Request to Forego 30-month D/F Testing if it Will Impair Performance of 

Hg Controls

Commenter (0511) requests that EPA grant affected sources the ability to forego 30-month D/F 

testing if it will impair performance of the mercury controls. Affected sources that make use of 

this exemption would continue to use the most recent temperature parameter established under 

LLL unless and until the affected source undertakes a change in operations that might adversely 

affect compliance with the D/F standard. The commenter concludes that this approach allows 

the highest level of mercury reductions while not compromising compliance with the D/F 

standards.

Response: We do not see a reason to forego the D/F testing. We know that D/F emissions can 

be significantly affected by operational changes such as changes in raw materials. Therefore, 

previous tests are no guarantee of future compliance. As noted above, we do not see the time 

spent performing D/F tests as being significant compared to the 30-day average. Also, no data 

were provided to indicate that D/F testing has any impact on the performance of mercury 

controls. 

4.37 Hg: Comment Regarding 63.1350(k) and (k)(3) and (4)

Commenter (0505 - Appendix G) stated "What if you do not have an in-line raw mill?" 

This comment is in reference to the following requirement: mercury CEMS per PS 12A or 12B. 

Sorbent trap CEMS QA by Procedure 5. RATA for PS12A, PS12B or Procedure 5 conducted 

with raw mill-on. [63.1350(k) and (k)(3) and (4)] 

Commenter recommends that the test be performed under normal operating conditions. Change 

63.1350(k)(4) to: “Relative accuracy testing of mercury monitoring systems under PS 12A, 

PS12B or Procedure 5 must be at normal operating conditions. If a facility has an inline raw mill 

the testing must occur with the raw mill on.”

Response: The EPA has clarified the rule language as the commenter suggests.
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4.38 Hg: Comment Regarding 63.1348(a)(5) and (b)(7) and 163.350(k)(3) and (k)(6)

Commenter (0505 - Appendix G) stated "If concentrations are assigned to each relevant hour, 

why should a sampling period be in multiples of 24 hours? Also 63.1348(b)(7) does not list 

testing option for alkali bypass in place of Hg CEMs as is discussed in 1348(b) for THC and 

HCl (note: it is included in 63.1350(k)(5))." 

This comment is in reference to the following requirement: for integrated sorbent trap CEMS 

assign the average concentration for an integrated period to each relevant hour spanned by each 

integrated sample. Therefore, not necessary to change traps at 12:00 midnight or only at integral 

24-hour intervals. But 1350(k)(6) states that you may use a monitoring period from 24 to 168 

hours in length and that is in a multiple of 24 hours. [63.1348(a)(5) and (b)(7) and 163.350(k)(6)] 

Commenter recommends that there is no reference to 24-hr intervals. Change 63.1350(k)(6): If 

you operated an integrated sampling Hg CEMS confirming to PS 12B, you may use a monitoring 

period from 24 hours to 168 hours in length. 

One commenter (AG) states that one issue with PS 12B is that when one is dealing with the 

small amounts of mercury caught in the Section 1 sorbent trap, the 5 percent breakthrough 

acceptance criteria is so small as to become unattainable. Because of the extremely low tolerance 

for breakthrough and the difficulty of avoiding cross contamination at those levels when 

analyzing the traps, the commenter has found that it is difficult to avoid invalidation of the traps. 

As a result, the commenter believes that there is a significant risk of a properly functioning 

sorbent trap system being unable to pass a RATA. The requirements in PS 12B are significantly 

more stringent than what is required under the comparable Reference Method against which the 

relative accuracy is evaluated. RA tests for sorbent trap systems are conducted with the source 

using PS 12B and the stack tester using EPA Method 30B. Unlike PS 12B, Method 30B allows 

up to 10 percent breakthrough on the Stage 1 sorbent traps unless the results are less than 1 

μg/dscm where they are then allowed up to 20 percent breakthrough. The commenter does not 

believe that there is a rational basis for holding the source’s Stage 1 sorbent trap breakthrough to 

5 percent while holding the stack tester’s Stage 1 sorbent trap breakthrough to 10 percent. They 

believe that EPA Method 30B establishes a much more reasonable and realistic acceptance 

criterion for breakthrough. Therefore, the commenter requests that EPA amend PS 12B to make 

it consistent with EPA Method 30B in this regard.

The commenter (AG) also requested that EPA specify that a source need only have a third, 

spiked section on the sorbent trap once per week, or better yet even once per quarter.. This would 

require a source that changed its sorbent trap once weekly to have a third, spiked section on 

every trap. However, for a source changing its traps every 24 hours, then a third, spiked section 

would only be required one day out of every 7 days.
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Response: The EPA has clarified the rule language for consistency and simplicity. A monitoring 

period from 24 to 168 hours in duration was intended to read “at least 24 hours but no longer 

than 168 hours.” 

The EPA agrees with the commenters’ concern regarding PS 12B and the section 63.1350(k)(3). 

The final rule allows for sources performing PS 12B to be held to the same breakthrough 

standard as the comparable Reference Method (i.e., EPA Method 30B).

The EPA does not agree with commenter’s request to only require third section on traps on a 

weekly or quarterly basis. The EPA designed PS-12B with the third section trap to provide 

accuracy information with each sample set and sees no reason to modify that requirement.

4.39 Hg: Comment Regarding 63.1346(f)

Commenter (0505 - Appendix G) stated "Must comply date is Sept 2015.Can a facility opt to 

comply with the Hg limit prior to that start date and then this would not apply at that point?" 

This comment is in reference to the following requirement: no fly ash with sorbent unless 

demonstrate no increase with mercury emissions. Does not apply once the facility must comply 

with a mercury limit. [63.1346(f)] 

Commenter recommends that if facility chooses to comply with Hg standard before compliance 

date, then fly ash restriction does not apply. Change 63.1346(f): ...Once the kiln must comply is 

in compliance with a mercury limit specified in 63.1343, this paragraph no longer applies.

Response: We agree and have made the suggested revision to 63.1346(f).

4.40 Start-up/Shutdown: PM Monitoring

One commenter (0505) stated that both proposed regulations (subparts F and LLL) require CEMS 

and CPMS be operated at all times the source is operating. The Subpart F requirements, however, do 

not address what is to be done with the CPMS measurements acquired during startup and shutdown. 

If the data are valid, they could be used to determine compliance with the general duty requirement 

to minimize air pollutant emissions under §60.11(d) at all times, including startup, shutdown and 

malfunction. In contrast, the proposed Subpart LLL includes explicit emission limits that apply 

during startup and shutdown for PM, D/F, Hg, THC, and HCl. The commenter expressed a number 

of concerns regarding EPA‘s proposed requirements to address startup and shutdown that fall into
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the three discrete areas: data-accuracy, emission testing, and emission calculation estimates. The 

commenter’s (0505) concerns are summarized in Sections 4.44 – 4.48.

Commenter (0519) is highly concerned about the impracticality and technical difficulties of 

measuring emissions during start up and shut down. The commenter notes that even when efforts 

are taken at plants to control emissions at all times, control devices are designed based on air 

flow rates within certain ranges, continuous emission monitoring systems (CEMS) 

measurements are only valid under normal operating conditions, and an arbitrary definition of 

startup and shut down makes it difficult to continue operations in a manner to ensure compliance 

with the various regulations and permits now in place for startup and shutdown. As such, the 

commenter supports PCA’s comments (Sections 4.44 – 4.48) addressing three key areas of 

concern related to startup and shutdown.

Commenter (0505) stated that PM monitoring data during kiln start-up and shutdown is not 

accurate or reliable and should not be used to determine compliance with the Subpart LLL PM 

concentration emission limit for startup and shutdown. PM CEMS and PM CPMS are inferential 

measurement systems that do not measure the PM concentration directly, but instead sense some 

other parameter that can be correlated to PM concentration under certain conditions. These 

monitors are not calibrated with National Institute of Standards and Technology (NIST) traceable 

standards. It is well known, and acknowledged by EPA in the preamble, that a PM CEMS 

accuracy response is affected by particle size distribution, refractive index, particle density and 

that these factors change over time even under normal operations due to varying feed materials 

and operating conditions, at cement plants. Particle size distribution, refractive index, particle 

density and other parameters are dramatically different during startup and shutdown (SS) as 

compared to normal kiln operations. During startup, these parameters continue to change as fuels 

are increased and feed is initiated and increased. Even a successful PM CEMS correlation 

established under normal conditions is not valid during start-up and shutdown. No valid measure 

of PM concentration can be provided by the required PM CPMS during start-up and shutdown.

Response: As discussed in the section IV.C. of the Preamble, the EPA agrees with the

commenter that measurement (either continuous or by stack test) of the regulated HAP and HAP 

surrogates during startup and shutdown events is too uncertain and unreliable to be used as a 

basis for compliance, and is adopting work practices instead. We thus agree with the thrust of 

these comments.

4.41 Start-up/Shutdown: Hg Monitoring

Commenter (0505) stated mercury monitoring data during kiln start-up and shutdown may not 

be accurate or reliable and should not be used to determine compliance with the Subpart LLL 

Hg concentration emission limits for start-up and shutdown. Inaccuracy in the mercury 

monitoring data may result from secondary effects due to changing molecular weight and/or 
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varying oxygen concentration that are not revealed by performing calibration gas injections or 

other quality assurance measures. For example, the commercially available mercury CEMS that 

have been demonstrated to be capable of meeting PS12A and Procedure 5 are dilution based 

CEMS. Varying effluent gas molecular weight during start-up and shutdown affect the sample 

flow rate through the critical orifice within the dilution module, which changes the sample 

dilution ratio and thus, biases the resulting monitoring data. Low gas molecular weight during 

startup (as compared to solid fuel during normal operation) without feed present (and without 

the associated CO2 from calcination of limestone) will bias monitoring data high. A second 

example was provided for mercury CEMS that use fluorescence based analyzers and nitrogen 

dilution to minimize effects of background oxygen quenching.

Response: We agree with the commenter that monitoring data during startup and shutdown 

events will not be sufficiently reliable to use as a basis for compliance during startup and 

shutdown and so have amended the standards to be work practices. We thus again agree with the 

thrust of this comment.

4.42 Start-up/Shutdown: Moisture Corrections

Commenter (0505) stated that inaccurate moisture correction factors will adversely affect the 

quality of CEMS data during start-up and shutdown. PM CPMS sense PM concentration on a 

“wet basis.” Hg, THC, and HCl CEMS are ―dilution extractive or “hot wet” monitoring 

technologies, and therefore provide wet basis concentration data. There is no need for effluent 

moisture values for calculating “normal operation” PM and Hg emissions, because these 

monitors are coupled with wet basis effluent flow rate monitors. A “normal operation moisture 

correction factors” is used to calculate dry basis THC and HCl emission concentrations and the 

site-specific moisture correction value(s) are determined during CEMS RATA, as allowed by

Part 98, Subpart C. Special moisture correction factors would be needed for start-up and 

shutdown because of the use of different fuels, different air flows, absence of kiln feed etc. and 

the factor may change during or between start-up and shutdown events. There is no practical 

means, under the proposed Subpart LLL start-up and shutdown emission limits, to determine or 

QA these factors which would need to be applied to adjust PM, Hg, HCl and THC 

concentrations to a dry basis.

Response: We agree with the commenter that monitoring data during startup and shutdown 

events will not be sufficiently reliable to use as a basis for compliance during startup and 

shutdown and so have amended the standards to be work practices. We thus agree with the thrust 

of this comment.

4.43 Start-up/Shutdown: HCl Monitoring
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Commenter (0505) stated the quality of HCl CEMS monitoring data at cement kilns is 

currently unknown and undocumented for both normal operating periods and start-up and 

shutdown periods, and many HCl CEMS are subject to potential spectral water vapor 

interference which may further detract from the accuracy of monitoring data, especially during 

start-up and shutdown when higher moisture levels may be encountered. HCl monitoring data of 

unknown quality should not be used to determine compliance with numerical HCl limits during 

start-up and shutdown. Representative sampling locations may not be present during start-up 

and shutdown and thereby render CEMS data inaccurate or non-representative. Brief spikes in 

Hg or HCl concentrations may occur during start-up and shutdown which are not-representative 

of actual emissions.

Response: We agree with the commenter that monitoring data during startup and shutdown 

events will not be sufficiently reliable to use as a basis for compliance and so have amended the 

standards to be work practices. We thus again agree with the thrust of this comment.

4.44 Start-up/Shutdown: Effluent Flow Rate Monitoring

Commenter (0505) stated effluent flow rate monitoring data will not be accurate or reliable 

during startup and shutdown and cannot be used even to estimate the “volume of pollutant 

emitted over the limit” in reporting deviations. The volume of pollutant emitted must be taken 

as the mass of pollutant emitted which is the product of the pollutant concentration times the 

effluent flow rate averaged over the startup and shutdown event. During much of the SS period 

for cold starts, and for almost all hot standby startup and shutdown periods, the effluent flow 

rate will be at a level below that which can be measured by effluent gas flow rate monitors. 

Neither ultrasonic time of flight flow monitors nor differential pressure monitors are capable of 

measuring accurately at very low gas flow rates. Neither can the EPA-reference Method 2 (used 

to calibrate flow rate monitors and perform flow monitor RATAs) be used to acquire accurate 

flow rate data. Effluent flow rate monitoring data cannot be used to estimate mass emissions 

during start-up and shutdown.

Emissions in hot kiln standby mode (stop fuel and feed, stop clinker production, minimum 

rotation of kiln, etc.) are start-up and shutdown emissions.

Application of a 7-day startup and shutdown average could result in an overly strict standard 

based on a few hours of data due to short duration kiln trips.

Response: We agree with the commenter that monitoring data use during startup and shutdown 

events at a cement kiln will not be as accurate as steady state conditions with respect to flow 

rates and contributes to the measurement uncertainty which justifies the change to work practices 

as the compliance regime (see section IV.C. of the Preamble).
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4.45 Start-up/Shutdown: Emissions Testing Issues

Commenter (0505) stated certain technical problems that adversely affect CEMS data quality 

would also adversely affect the quality of any emission testing data performed during startup 

and shutdown. For example, effluent stratification at very low flow rates during startup and 

shutdown could result in non-representative measurement locations or sampling points; 

especially for single-point sampling methods.

PM testing and D/F testing using the specified EPA isokinetic sampling procedures cannot be 

performed during very low gas velocities that may be encountered during startup and shutdown.

Transient effluent conditions and changing effluent concentrations during startup and shutdown 

present significant technical challenges and detract from emission test data quality. EPA test 

methods, such as Method 5 for PM and Method 23 for D/F and other methods that require 

traversing the stack cross-section to collect samples at specified points, are intended to be 

performed at constant, steady state conditions. Under steady-state conditions, the traversing test 

method is expected to provide results that account for spatial variation in the pollutant and gas 

velocity over the cross-section. If there are also concurrent temporal changes in the flow rate 

and/or pollutant concentration during the test run, then it is not possible to determine if the 

principal of proportional sampling is correctly applied (acquiring a sample volume proportional 

to the axial gas velocity at each sample point) so that the test run result approximates a surface 

integral over the cross section. Significant changes to the PM and D/F sampling methodologies 

would be required to apply these emission test methods for use during startup and shutdown at 

cement kilns.

Emission testing cannot be performed for startup and shutdown during short hot standby kiln 

outages. Rapid shutdowns and hot kiln standby operation are startup and shutdown emissions, 

but are unplanned and unpredictable events and of highly variable duration. Each such event may 

have very different emissions based on the specific circumstances. Test personnel and equipment 

cannot be mobilized for these events. No cement plant operator would simulate such an event for 

the purposes of emission testing in view of safety considerations for personnel and for the kiln 

system equipment.

Response: As discussed in section IV.C. of the Preamble, we agree with the commenter that the

transient and changing effluent conditions and concentrations at cement kilns during startup and 

shutdown create enormous uncertainty such that measurements cannot be compared to those 

under steady state conditions, and that measurements are too unreliable to be considered 

practicable within the meaning of section 112 (h) (2) (B) of the Act.
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Comment: Start-up/Shutdown: Emissions Calculation Estimates

Commenter (0505) stated the proposed emission limits and emission calculation requirements 

for startup and shutdown are inconsistent and need to be reconciled. The proposed kiln startup 

and shutdown emission limits for PM, D/F, Hg, THC, HCl are all expressed as concentrations 

and certainly do differ from the emission standards that apply during normal operation. “The 

volume of pollutant emitted” must be taken as the mass of pollutant emitted which is the 

product of the pollutant concentration times the effluent flow rate averaged over the startup and 

shutdown event. As written, the proposed regulation would require (i) reporting every kiln 

startup and shutdown event, (ii) identifying each such event that exceeds the specified 

concentration limit, and (iii) an estimate of the mass of pollutant emitted during the event. If the 

mass of pollutant emitted is the point of EPA concern, then expressing the startup and shutdown 

emission limits on the same mass basis would, at least, be consistent. The mass emitted to the 

atmosphere during startup and shutdown will certainly be a small amount compared to normal 

operation emission rates, even if there are some elevated transient pollutant concentrations.

The proposed pollutant mass emission calculation requirements for startup and shutdown cannot 

be expected to provide consistent results between plants or results having known quality. 

Without having accurate information regarding the pollutant concentrations and/or the effluent 

flow rate, the plant operator cannot estimate the volume of pollutant emitted with even a poor 

level of confidence. Consequently, in order to estimate mass emission, plant operators would be 

forced to engage in the following process: (i) use a guesstimate of pollutant concentration 

coupled with an estimate of fuel used, (ii) use look-up F-Factors (volume of effluent gas 

generated at zero% O2 per unit mass of fuel) for the fuel(s) and/or fuel combinations to determine 

stoichiometric flow rates, and (iii) engage in additional guesstimates of actual kiln and/or 

precalciner oxygen levels (too high to measure accurately with stack O2 monitor). Kiln-specific 

circumstances would also certainly need to be taken into account. 

Response: As discussed in section IV.C. of the Preamble, we agree with the commenter that the 

technical issues discussed above will decrease the level of confidence in the results of the 

emissions calculations. 

Comment: Commenter (0505) stated that for all the reasons they discussed, the startup and 

shutdown provisions proposed for Part 63 Subpart LLL cannot be applied in a consistent manner 

and do not rise to what can be called reasonable “standards” and need to be replaced by work 

practice standards. The commenter suggested the following work practices for start-up and 

shutdown: 

Proposed Start-up Work Practices: As a general matter, operators will focus on employing

good combustion practices for the purpose of minimizing emissions during these periods. 

Accordingly, the air pollution control device will be turned on and operating before any fuels are 

combusted. Once the air pollution control device is running, start up fuel (generally natural gas 
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or fuel oil) will be combusted to bring the kiln gradually up to approximately 1200-1300°F. 

Combustion of primary fuel (generally coal or petroleum coke) will then begin and small 

amounts of kiln feed may be introduced into the kiln concurrently. Start-up concludes when feed 

has been continuously fed to the kiln for at least 120 minutes or when the kiln feed rate exceeds 

sixty percent of the kiln design rate. Oxygen concentrations, feed input and the temperature 

profile in the kiln system will be monitored during start-up as a means of ensuring good 

combustion. The type and duration of each start-up will be recorded. 

Proposed Shutdown Work Practices: Shutdown will commence once the feed to the kiln is 

turned off. Emissions during this period will be minimized, as the air pollution control device 

will continue to run until the kiln ceases to rotate continuously, which is when the shutdown 

period concludes. The type and duration of each shutdown will be recorded.

Response: We agree with the commenter and have added work practice standards into the final 

rule.

4.46 Start-up/Shutdown: Opposition to Record Keeping in Lieu of CEMS for 

Compliance Demonstration

One commenter (0508) stated that EPA’s proposal to eliminate the requirement that sources use 

CEMs to demonstrate compliance during startup and shutdown and to allow them to show 

compliance through nothing more than their own records seeks to justify the change by claiming 

it expects emissions to be below standards. Even if the revised standards were lawful and nonarbitrary, recordkeeping by itself does not assure compliance and is therefore both unlawful and 

arbitrary.

Response: We have removed the numerical emissions limits from the final rule and have 

replaced them with work practice standards that require the type and duration of each startup and 

shutdown event to be recorded. As discussed in Section IV.C of the Preamble, numeric limits for 

these events is not feasible nor practicable within the meaning of CAA Section 112 (h).

4.47 Dioxin/Furan: Monitoring of Carbon Injection Rates

One commenter (0511) stated that the proposed rule is not clear as to when to monitor carbon 

injection rates when performing dioxin/furan (“D/F”) testing. The commenter stated that when 

Subpart LLL was first implemented, the only reason for utilizing ACI was for D/F control 

purposes. The rule required that if ACI is used, that the injection rate must be monitored and 

compliance demonstrated based on the 3-hour average sorbent injection rate. The commenter 
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stated that with the addition of mercury standards, there are affected sources that utilize carbon 

injection for mercury control but not for D/F control. Since all kilns are now required to 

continuously monitoring for mercury, the commenter concludes there is no reason to conduct 

parametric monitoring of the sorbent type/injection rate. The commenter therefore requests that 

the regulations be amended to clarify that if sorbent injection is used for D/F control, then the 

source must comply with the parametric monitoring requirements related to sorbent type and 

injection rate. However, if sorbent injection is used for mercury control, then these parametric 

monitoring requirements do not apply. Specifically, the commenter recommended that 

63.1346(c) be revised to read:

“For an affected source subject to a D/F emissions limitation under §63.1343 that 

employs sorbent injection as an emission control technique for D/F control, you must 

operate the sorbent injection system in accordance with...”

The commenter also request similar revisions to the proposed language in 40 C.F.R.63.1346(d) 

and (e) to clarify when the D/F sorbent monitoring requirements are applicable.

Response: This comment is outside the scope of this proceeding, since EPA did not reconsider, 

seek comment on, repropose, or otherwise reopen the issue of data used to establish the floors. 

EPA simply recalculated floors after removing CISWI kilns from the database. See 77 FR 42372. 

If, against our view, any response is deemed necessary, EPA notes that it did not establish any 

floors with our without non-detectable measurements. See Portland Cement Reconsideration 

Technical Support Document, June 15, 2012 (Docket item EPA-HQ-OAR-2011-0817-0225) 

where datasets are set out.

Comment: THC and oHAP Alternative: Opposition to non-detects being counted at the 

detection level

Commenter (0507) opposed the adoption of methodology to treat non-detects as detection-level 

emissions, as it is overly conservative and we believe falsely represents oHAP emissions when 

in fact they may not exist. The commenter stated that the EPA does not explain in either its 

preamble or its TSD its rationale for changes to this definition so as to treat non-detects as 

detection level emissions (as opposed to zero values, as the current definition provides.) The 

commenter stated that failure to explain such a reversal is a violation of CAA §307(d) and 

settled case law, and would be reversible on judicial review. E.g., Small Refiner Lead PhaseDown Task Force v. EPA, 705 F.2d 506, 551 (D.C. Cir. 1983) (holding that “a rule without a 

stated reason is necessarily arbitrary and capricious”). The commenter recommended that EPA 

reverse its decision to require all non-detects to be counted at the detection level.
106

Response: The EPA has responded to this comment in the National Emission Standards for 

Hazardous Air Pollutants for Major Sources: Industrial, Commercial, and Institutional Boilers 

and Process Heaters; Final Rule in 76 FR 15623 or available here: 

http://www.epa.gov/ttn/atw/boiler/fr21mr11m.pdf.

4.48 THC and oHAP Alternative: Opposition to Annual Testing Requirement

One commenter (0505) stated that testing for oHAPs and establishing the alternate THC limit 

should be conducted every 30 months as in the September 2010 promulgated NESHAP, not 

annually, as is proposed. The compliance testing required for the various pollutants (i.e., PM, 

HCl, THC, oHAP, Hg and dioxin/furans (D/F)) should be aligned and required to be done every 

30 months rather than staggered as the rule has currently proposed. This is not only practical 

from a testing perspective, but also much more cost effective when compared with staggered 

testing.

Commenter (0507) stated that annual THC/oHAP testing is unnecessary and overly burdensome. 

The commenter stated that if the EPA accepts that THC and oHAPs are reasonably correlated, 

then unless a source undertakes a major change in raw materials or fuels, it is unlikely that this 

correlation will change appreciably. The commenter recommended that the EPA revise the 

testing requirement to every 30 months, and adopt language similar to what exists for D/F 

testing, whereby if a change is made that is anticipated to impact the THC/oHAP correlation, that 

the source is obligated to retest.

According to commenter 0505, EPA provided no justification to increase the frequency of the 

oHAP/alternate THC limit testing from 30 months to annually. This testing is expensive with a 

stack test of the organic HAPs costing between $20,000 and $30,000 per test. Because the rule 

has a mechanism to trigger retesting if there is a significant change in the THC indicator level, 

the agency already has a mechanism to require retesting as appropriate, without the need for 

annual testing.

The commenter (0505) stated that there are benefits of a 30 month cycle for testing of HCl, D/F, 

oHAPs and other constituents. Testing every 30 months coincides with the currently required 

testing for HCl for wet scrubber equipped kilns (which is being extended to dry scrubbers) and 

testing for D/F. This is significant because FTIR Method 321 testing for HCl can be combined 

and performed simultaneously with oHAP FTIR Method 320 testing for formaldehyde and 

acetaldehyde. Concurrent testing for oHAPs using EPA Method 18 (benzene, toluene, xylene 

and naphthalene) would be combined with Method 320/321 by taking a slipstream from the 

FTIR sampling system to acquire adsorbent tube samples. This would allow for multiple 

adsorbent trap samples to be acquired along with the FTIR direct interface testing and reduce the 

costs for performing tests. Testing every 30 months also coincides with required testing for D/F, 

which are known to form thermally from HCl and organic compounds in the process at certain 

temperatures. It is a natural outcome that testing for HCl and oHAPs be conducted concurrently 
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with D/F testing on a 30 month basis. 

At some sources, re-tests inside of the 30 month time frame will be triggered to establish a new 

alternate THC limit when the existing alternative THC limit is exceeded. Therefore, these 

facilities would be required to conduct testing more frequently than every 30 months. However, a 

facility whose alternate THC limit is not exceeded and remains within the compliance margin 

should not be penalized by arbitrarily having to conduct annual testing. 

Response: EPA has considered the comment and reviewed the information provided by the 

commenter. EPA agrees with the commenter that testing every 30 months, instead of annually, 

will allow the industry to synchronize their organic HAP testing with their testing for D/F and 

HCl compliance and is, therefore, more efficient and cost effective. We also believe that that 

testing every 30 months will not have an adverse affect on organic HAP emissions since each 

source will be conducting continuous parametric monitoring of THC to demonstrate that proper 

control of organics is on-going. Therefore, the testing frequency in the final rule for organic 

HAP (for those sources opting for this compliance alternative) is every 30 months.

4.49 THC and oHAP Alternative: Request for Five Year (60 months) Testing 

Frequency for Raw Material Dryers, Coal Mills and Alkali Bypass Stacks

Commenter 0505 stated that oHAP emissions from regulated raw material dryers, coal mills 

and alkali bypass stacks should be tested every five years (60 months) or whenever a significant 

change in design or operation of these exhausts occurs. Alternatively, kiln operators should 

have the option of demonstrating on a one time basis that the oHAP concentration from these 

other sources are equal to or less than those in the kiln and not be required to test those stacks 

thereafter.

Response: The commenter provided no justification for a change in testing frequency. In order 

to assure that all emission points do not exceed the standard when emissions are summed, and to 

ensure consistency among testing timelines, we are keeping testing timelines for regulated raw 

material dryers, coal mills and alkali bypass stacks the same as the main stack testing timeline..

Comment: THC and oHAP Alternative: Request for Alternate Way to Select Monitored 

THC Level

The commenter (0505) stated that EPA‘s proposal to set the THC threshold for compliance 

monitoring at the highest 1-hour THC value during the organic HAP stack test plus 10 percent 

is virtually guaranteed to trigger frequent retests – even as soon as the day after the stack test –
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without regard to whether organic HAP emissions have actually increased. Requiring such 

retesting under such circumstances is unreasonable and arbitrary. 

To demonstrate this problem, the commenter obtained hourly THC CEMS data for 4 kilns over 

periods as long as one year. In all cases, 30-day average THC emissions for the kilns average 

more than 24 ppmv during the year and are, therefore, candidates for demonstrating compliance 

using the alternative oHAP standard. The commenter divided the period of operation into 3-hour 

blocks for each kiln. To simulate what would happen under EPA‘s proposed approach, the 

commenter selected a sample of one thousand 3-hour blocks for each kiln and set the THC 

threshold to be used in monitoring at 110 percent of the highest 1-hour THC reading in each 

block. The commenter then compared each of the one thousand threshold values against the 

kiln‘s sequence of 30-day THC averages, beginning with the day following the oHAP

performance test, to determine the date of the first oHAP retest trigger. The commenter 

summarized the results of their analysis in Table 1 below.

Table 1: Frequency of Retest Triggers Using EPA Proposed Method (Based on Highest 1-

Hour THC Value Plus 10%)

Kiln A Kiln B Kiln C Kiln D 

Length of Record (days) 123 113 355 238 

Average THC, ppmv dry at 

7% O2 

27 28 37 44 

Probability Distribution for Days Until First Retest Trigger 

Next Day 29% 56% 19% 29% 

Within 30 Days 43% 69% 26% 44% 

Within 90 Days 58% a/ 39% 61% 

Distribution of THC Retest Thresholds (110% of Highest 1-Hour THC during Stack Test) 

Maximum, ppmv 97 207 292 380 

Average, ppmv 32 33 46 50 

Minimum, ppmv 15 6 1 0 

Probability of Retest 

Threshold < 24 ppmv 

22% 48% 5% 2% 

a/ The length of record is too short to track Kiln B for 90 days following the performance test 

The commenter stated that for Kiln A (assuming that THC monitoring data preceding the oHAP 
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test are used to calculate 30-day rolling averages beginning the day after the oHAP test), the 

analysis showed that: 

• 29 percent of the time, the THC threshold will be set at a level that will trigger a retest on 

the day after the oHAP stack test, 

• 43 percent of the time, it will be set at a level that will trigger a retest within 30 days 

• 58 percent of the time, it will be set to trigger a retest within 90 days. 

• While this kiln has THC 30-day averages that are above 24 ppm on a regular basis, 

twenty two percent of the time EPA‘s proposed method for setting the retest trigger 

results in an alternative THC limit that is less than 24 ppmv. 

For Kiln A as an example, EPA’s method allows the retest trigger to be set as low as 15 ppmv 

and as high as 97 ppm compared to the kiln‘s average THC emission level of 27 ppmv. The 

commenter stated that the simulations for the other kilns support these findings. Therefore, the 

required retest that is triggered is unnecessary, unreasonable, and arbitrary. According to the 

commenter, the excessive frequency of organic HAP retests is an unintentional, but unavoidable, 

consequence of using only hourly THC emissions at the time of the stack test to set the retest 

trigger. Frequent retests will result in a significant, unwarranted, and unnecessary cost burden to 

the industry. EPA needs to address and correct this problem in the final rule.

The commenter (0505) proposed an alternative approach to setting the alternative THC limit 

based on the highest daily average THC level achieved in the 30 day period up to and inclusive 

of the day of the stack test. The THC threshold that triggers a retest would be the highest day 

value plus 10 percent. The commenter re-ran the simulations discussed above, using 110 percent 

of the highest daily THC average in the preceding 30 days as the threshold to trigger a retest. In 

no instance does the highest-day method trigger a retest on the day following the performance 

test. While oHAP retests may be triggered at later times during the period of the data for each 

kiln, the frequency of retests is more consistent with the intent of EPA‘s proposed approach. 

While this method eliminates the occurrence of immediate retests on the day following the 

performance test, it does not prevent a retest trigger from occurring relatively soon after the 

performance test. For Kiln A, we find that a retest will be triggered within 30 days 8 percent of 

the time, and within 90 days 15 percent of the time. In the highest day method, the THC 

threshold is almost always set at a level above the long-term THC emissions of the kiln (27 

ppmv). In no instance does the highest day method set the THC threshold below the 24 ppmv 

level of the primary THC standard. The commenter stated that the simulations for the other kilns 

support these findings.
110

The commenter stated that while the highest day method still can trigger retesting relatively soon 

after the performance test, the commenter concluded from these results that it is a much fairer 

and more reasonable approach than using a single hour from the time of the oHAP test. Once an 

appropriate compliance margin is established and used to adjust the THC threshold upward, a 

future 30-day average for THC emissions that exceeds the margin-adjusted threshold would be 

an indication that HAP emissions may have increased above the 12 ppm standard, which would 

justify an investigation of the cause and could be the basis for organic HAP retesting.

Response: The EPA understands the concerns of the commenter and has revised the organic

HAP parametric compliance option in the final rule to allow more flexibility for sources with 

variable THC emissions which show good compliance with the organic HAP compliance tests. 

While we understand that sources have variability and in the case of THC some of that 

variability is not avoidable, especially in terms of fuel variability, and we do not wish to create 

an undue testing burden for sources with high THC values and very low organic HAP emissions, 

we are not inclined to adopt the suggested approach offered by the commenter allowing them to 

choose their highest value from the previous 30 operating days and add ten percent to that value 

to construct their parametric monitor operating limit. We received other comments offering 

organic HAP scaling ideas as well, but found them to be not as protective of the emission 

standard (i.e reliably demonstrating continuous compliance) as we wish to remain. As an 

alternative to these approaches we adopted a version of the approach now used for PM CPMS 

monitoring whereby we allow a source who demonstrates compliance with the organic HAP 

standard below 75% of the emission limit to use their parametric THC monitor equivalent of that 

75% standard as their 30-day rolling average operating limit, and a source who demonstrates 

compliance with the organic HAP standard at or above 75% of the organic HAP standard will set 

its 30-day rolling average operating limit as the average THC parametric monitor value recorded 

during the three organic HAP compliance test runs. For example, if a source demonstrates 

compliance with the organic HAP limit with a set of Method 18 tests that show a total organic 

HAP average concentration of 5.2 ppmv, and during that testing the source parametric THC 

monitor recorded 45 ppmvw, the 30-day rolling average parametric THC operating limit would 

be calculated by dividing 9 (75% of the organic HAP emission limit) by the measured organic 

HAP value (5.2) and multiplying the parametric THC monitor (45 ppmvw) average by that value 

(1.73). This would establish a parametric THC 30-day rolling average operating limit of 81.3. A 

source which shows compliance with the organic HAP emission limit at or above 9 ppmv would 

set their parametric THC 30-day rolling average operating limit at the average parametric THC 

value recorded during the compliance test. More discussion on organic HAP scaling is found in 

sections III and IV to the preamble to this rule. 

4.50 THC and oHAP Alternative: Support for Extending Testing Time and 

Number of Tests to Adequately Capture Variability

Commenter 0505 stated that oHAP testing provisions and corresponding THC measurements 

should be changed to provide explicit flexibility in conducting these tests as discussed in the 

preamble and as needed to account for test method imprecision and detection limits, emissions 

variability, and other factors. The commenter supported the approach suggested by the preamble 
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“...allowing facilities to extend the testing time (or number of tests) if they believe extended 

testing is required to adequately capture THC variability over time. 77FR 42381

The commenter stated that longer duration test runs may be needed to achieve lower detection 

limits which will avoid overstating oHAP emissions by reporting non-detects at their detection 

limits and summing those values in the total oHAP measurement that is compared to the 12 

ppmv limit. Longer test runs may improve method precision for Method 18 adsorbent tube 

sampling due to collection of greater amounts of analyte. Additional test runs should be allowed 

to be performed at the discretion of the source operator in order to capture short-term emission 

variability, and to reduce the estimate of the standard deviation of the samples (which may be 

advantageous in scaling up oHAP values to conservative levels protecting the standard). 

Additional test series (3 or more runs per test) should be allowed to be conducted at the 

discretion of the source operator at conditions that reflect emission levels above normal 

representative emissions. 

The commenter requested that EPA revise the language EPA has proposed for 

§63.1349(b)(4)(iii), as follows:

(iii) Use Method 320 of appendix A to this part, Method 18 of Appendix A of part 60, ASTM 

D6348–03 or a combination to determine emissions of total organic HAP. Each performance test 

must consist of at least three separate runs. Additional and longer duration runs are allowed. The 

performance testing must be conducted under the conditions that exist when the affected source 

is operating at the representative performance conditions in accordance with § 63.7(e) and/or at 

the sole discretion of the plant operator, at such conditions that may represent higher emissions 

or worst case conditions. Each run must be conducted for at least 1 hour. You must conduct the 

performance test while the raw mill of the kiln is operating and while the raw mill of the kiln is 

not operating. 

The commenter stated that revisions to the text of § 63.1349(b)(4)(iv) are needed as follows: 

(iv) At the same time that you are conducting the performance test for total organic HAP, you 

must also determine a site-specific THC emissions limit by operating a CEMS in accordance 

with the requirements of § 63.1350(j). The duration of the performance test each test run must be 

3 hours and the highest 1-hour average THC concentration (as calculated from the 1-minute 

averages) during the 3-hour test must be calculated must be 1 hour or longer and each 

performance test must include three or more test runs. Using the fraction of time the raw mill is 

on and the fraction of time that the raw mill is off, calculate the site-specific THC emissions limit 

as a weighted average of the highest 60- minute or one-run average THC levels measured during 

raw mill on and raw mill off testing.
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Response: The EPA maintains the requirements of the general provisions that compliance is 

based on the arithmetic mean of three test runs but we do recognize the need to extend test 

duration to help ensure better detection and include an appropriate assessment of process 

variability. Sources and testers must use their best judgment to determine if the minimum sample 

volume specified in the rule is sufficient to provide data that appropriately characterizes the 

emissions of the source. 

4.51 THC and oHAP Alternative: Request for Compliance Margin (Scaling) 

between Tested Value and Limit

Several commenters (0505, 0506, 0507, 0523) stated that EPA should allow a scaling up of the 

alternative THC monitoring limit. The commenter (0505) stated that EPA should allow a 

performance-based mathematical scaling up of the alternative THC monitoring limit when the 

actual measurement results of total oHAP tests are below the 12 ppmv limit so that sources with 

low oHAP emissions below the oHAP limits are not unfairly penalized by having to retest when 

there is no evidence that the 12 ppmv limit has been exceeded. 

The commenter stated that a more appropriate response would be to apply a conservative 

statistical adjustment to the emissions determined during the performance test to control the risk 

that the allowed margin has been overstated. The following equation provides a conservative 

method to scale up the THC value established at the time of testing to an adjusted THC limit that 

is equivalent to the 12 ppmv oHAP limit: 

THCAdjusted= THCSelected × [12 /(oHAP@7%O2+STDM) ]

Where: 

• oHAP@7%O2 = Mean of the N test runs (3 or more runs) oHAP determinations 

corrected to 7%O2 dry basis 

• STDM = Standard deviation of the mean of the N oHAP determinations 

• THCSelected = The THC value selected as the threshold for monitoring oHAP

compliance. In PCA‘s proposed approach, this would be 110% of the highest dailyaverage THC value during the 30 days ending with the oHAP performance test. 
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• THCAdjusted = The adjusted alternative compliance limit, wich is a conservative 

estimate of the THC concentration equivalent to the 12 ppm OHAP limit at 7% O2 based 

on the mean and standard deviation of the mean of the oHAP test runs. 

• Note: The THCSelected and THCAdjusted values in the above equation are corrected to 

7% O2 

In this, the oHAP emissions would first be adjusted upward by 1 times the actual standard 

deviation of the mean of the triplicate (or more) test runs conducted during the stack testing. (If 

N test runs are conducted, the standard deviation of the mean equals the standard deviation of the 

test runs divided by the square root of N.)

According to the commenter, this method is a performance-based approach that provides an 

incentive for kiln operators and their testing contractors to achieve improved levels of accuracy 

and precision in organic HAP testing. This incentive will encourage the use of more skilled 

testing labs and give all testing contractors the incentive to improve their measurement precision. 

There would also be an incentive to increase the number of test runs that are conducted in order 

to reduce the uncertainty in average HAP emissions determined during the stack test.

Commenter (0507) disagreed with the proposed decision to not allow sources to scale up their 

surrogate THC levels to represent the full oHAP limit of 12 ppm. The commenter opposed the 

change in detection limits, which the EPA uses to justify raising the oHAP limit from 9 ppm to 

12 ppm. The commenter stated that this has no impact on the correlation between oHAP and 

THC for a particular kiln other than to dampen the true correlation ratio. The commenter stated 

that by requiring non-detects to be added to the oHAP concentration at the detection level, EPA 

could safely allow a scaling up with a high degree of assurance that the increase in the surrogate 

THC level is at its minimum and likely underestimates the true oHAP to surrogate THC ratio. 

The commenter stated that by allowing a scaling up, sources would be far less likely to trigger 

the need to retest than under the current proposal. The commenter recommended that EPA allow 

scaling up of the THC limit.

Commenter (0507) expressed concern that if a source emits oHAPs at a very low level and the 

surrogate THC level is marginally above the THC limit of 24 ppm, the source will actually be 

regulated to a much more stringent standard. The commenter stated that the EPA’s approach to 

resolve this, allowing sources to test repeatedly or for longer, is random and costly in lieu of 

allowing a scale up approach.

Commenter (0523) stated that in regard to the testing time needed to capture THC variability, the 

commenter stated that THC emissions are a function of the raw materials and emissions are 

cyclic and may vary significantly from month to month rather than hour to hour. The commenter 
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provided two options to address this issue: (1) change the language in §63.1349(b)(4)(vi); or (2) 

allow a source to scale up its emissions during the annual performance test. The commenter 

suggested that the language in §63.1349(b)(4)(vi) should simply be changed to add “30-day 

rolling average” as a clarification, so if the THC site-specific 30-day rolling average exceeds the 

established site-specific THC emission limit by 10 percent or more, then a source must comply 

with §63.1349(b)(4)(vi) (A) and §63.1349(b)(4)(vi)(B).

The commenter (0523) asked the EPA to reconsider its position and allow a source to scale up its 

emissions based on data provided in the comment letter as Figure 2 [page 7]. The commenter 

suggested that the relationship between oHAPs and THC is linear and can be used to scale up 

emissions therefore avoiding needless retesting.

The commenter (0523) stated that if the EPA does not allow emissions to be scaled upward 

based on the annual testing, it should at least allow a source to: (1) develop a site-specific oHAP

and THC relationship that may be used to scale up once the source has proven a relationship 

exists; or (2) develop a “performance based” approach by substituting the actual standard 

deviations (SD) of the OHAP and THC measurements for each particular test series. The 

commenter noted that the approach would provide the following advantages: (1) it’s a 

performance based approach; (2) the standard deviations are based on actual data not theoretical 

values; and (3) the approach is very similar to that in Subpart Da. The commenter provided an 

equation to calculate the THC operating limit:

THC operating limit = [12/(OHAP ppmdv + OHAP SD)] *(THC ppmdv – THC SD)

Response: See response to comment 4.50 above, and discussion in the sections IV.A and III.A.3 

to the final rule Preamble. EPA notes in addition that although organic HAP measurements

above 4 ppmv and below 12 ppmv are not sufficiently reliable to serve as a basis for 

compliance, these are real values (i.e. values below 12 ppmv would not indicate a non-detect). 

As such, EPA believes the values are sufficiently reliable to use as a basis for determining a THC 

level for purposes of parametric monitoring. Put another way, although imprecise, these 

measurements are sufficiently reliable to establish a calibrated THC parametric monitoring value 

that demonstrates continuous compliance with the organic HAP standard, as well as calculating 

emission rates, but not sufficiently reliable to ascertain compliance. This difference reflects a 

reasonable distinction between compliance monitoring and establishing the level of a monitored 

parameter. 

4.52 THC and oHAP Alternative: Suggestions for Rule Improvement

One commenter (0505) made the following recommendations regarding the THC/oHAP

standards: 
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Comment: oHAP retesting should not be triggered when it can be shown that the exceedance of 

the alternative THC limit is due to a malfunction, or the cause has been determined and 

corrected, or the THC exceedance is due to an increase in methane emissions only. 

Response: We believe the current malfunction provisions would preclude a requirement for 

a retest, as a result of a malfunction.

Comment: EPA should add an explicit option under the oHAP alternative that allows one to set 

a non-methane THC limit and track compliance with that limit rather than a THC limit that is 

used to determine when retesting is needed for sources with high levels, or highly variable levels 

of methane. The choice of monitoring non-methane THC should not be left as an option which 

requires approval on a case-by case basis. Several monitoring approaches should be allowed, 

including (a) the use of non-methane analyzers (flame ionization detectors with methane cutters), 

and (b) direct measurement of methane with a IR-based analyzer or other analyzer and 

subtraction of the methane ppmv measured divided by three from THC analyzer response. 

Response: For the purpose of demonstrating compliance with the oHAP limit, the EPA allows

parametric THC monitoring in the final rule. Sources wishing to set a site-specific non-methane 

THC limit and continuously monitor non-methane THC with a technology sufficient to measure 

methane directly, as well as THC, may apply for an alternate monitoring approval using the 

procedures for such applications in section 63.8(f) of the General Provisions. Technologies 

sufficient to conduct such measurements generally measure methane with a GC separation 

approach followed by a backflush with GC measurement of the remaining hydrocarbons. 

Comment: The text of proposed § 63.1349(b)(14)(iii) need to be revised to clarify that the 

requirements to conduct oHAP testing with and without the raw mill in operations will only 

apply to in-line kiln/raw mill systems. As currently written, all systems would be required to 

conduct raw mill on and off testing. Such expansive testing would serve no beneficial purpose 

and we do not believe that is what EPA intends. 

Response: The EPA has modified the requirement in the final rule to clarify that organic HAP 

testing with mill on and mill off conditions only apply to kilns with an in-line raw mill.

Comment: In the event that a source operator elects to conduct a series of performance tests 

under a series of operating conditions which may reflect variations in emissions for the purpose 

of determining appropriate operating conditions for control systems and methods, any 

performance test data exceeding the applicable limit should not be used as evidence of an 

emission violation during the test period, so long as the unit is returned to normal operating 

conditions and emissions determined during those conditions indicate compliance.
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Response: Section 112 of the CAA requires continuous compliance with all emission 

standards. For that reason, it is not appropriate to add provisions to the rule that would allow 

exceedance of an emissions limit.

4.53 THC and oHAP Alternative: General Support

One commenter (0475) supports EPA’s proposed changes to the continuously monitored 

parameters for alternative organic HAP Standard with THC monitoring parameter.

Response: EPA noted the commenter’s support for the oHAP alternative.

4.54 THC: Comment Regarding 63.1349(b)(4) and 63.1350(i)

Commenter (0505 - Appendix G) stated "Need Method 8 if a facility chooses a non-methane 

approach for THC monitoring for the Alternative OHAP option. For PS-8A, RATA does not 

apply." 

This comment is in reference to the following requirement: THC CEMS per PS-8A. Span value 

(as propane) is 50 ppmvd and reference method is Method 25A. If kiln gases are diverted 

through an alkali bypass or coal mil to separate stacks a kiln-specific THC limit must be 

calculated per Eq. 5. [63.1349(b)(4) and 63.1350(i)] 

Commenter recommends that option be provided of 8 or 8A. Change 63.1350(i)(1): You must 

install, operate and maintain a THC continuous emission monitoring system in accordance with 

Performance Specification 8 or 8A, of Appendix B to Part 60 of this chapter.

Response: The EPA agrees with the commenter and has modified the rule language as 

suggested.

4.55 Coal Mills/Alkali Bypass: General Support 

One commenter (0475) agreed with and supported EPA’s proposal that the aggregated sum of 

mercury, THC, and HCl measured in both the kiln exhaust and the coal mill exhaust streams 

must not exceed the Supbart LLL NESHAP emission limits for each respective HAP or HAP 

surrogate. The commenter believes that the performance tests for mercury, THC, and HCl on 
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the diverted kiln exhaust to the coal mill should be carried out downstream of the coal mill 

APCD.

Response: EPA noted the commenter’s support for the required accounting of diverted kiln gas.

4.56 Coal Mills/Alkali Bypass: Correction to Kiln Gas Diversion Equation

Commenter (0523) agreed with the EPA’s approach for the situation where a coal mill which 

receives and discharges some of the cement kiln exhaust gas directly to the atmosphere must 

demonstrate Hg, THC and HCL emissions. The commenter noted that the equation shown in the 

proposed rule contains a minor mistake. The commenter stated that in the example provided in 

the proposed rule, all of the volumetric concentrations are corrected to 7% Oxygen; however the 

exhaust flow rates were not correct to 7% oxygen. The commenter stated that because HCl and 

THC are measured upstream of the coal mill and the exhaust gas flow rate is the total flow from 

the coal mill, the commenter stated that these gas flow rates should also be normalized to 7% 

oxygen prior to calculating the above equation.

Response: Pollutant concentrations are commonly corrected to normalize their values respective 

to a diluent concentration (i.e. 7% oxygen) and we note that the equation handles oxygen 

correction appropriately respective to pollutant concentration correction. Flow rate values 

include measurement of the gas stream molecular weight (oxygen, nitrogen, and carbon dioxide) 

and are standardized respective to barometric pressure and reference temperatures, but are not 

corrected to a standard diluent value. As such, we disagree with the commenter and are not 

making the edit to the final rule that the commenter suggests.

4.57 Coal Mills/Alkali Bypass: Request for Site Specific Monitoring Programs for 

Coal Mills 

Commenter 0507suggested requiring cement kilns that use kiln gases as drying heat in their 

coal mills to develop site-specific alternative monitoring programs to account for the mercury, 

THC/oHAPs and HCl contribution in any gases that are either emitted directly to atmosphere 

through the coal mill stack, or that are returned to the kiln exhaust gas system and become comingled with the other kiln exhaust gases. The commenter noted that each kiln is unique, so 

standards that cover all situations are not feasible.

Response: We have included language in Sections 63.1349 and 63.1350 to accommodate the 

different configurations found at various facilities. For configurations that are not addressed, the 

facility can request approval for an alternative monitoring plan under Section 63.1350(o).
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4.58 Coal Mills/Alkali Bypass: Request for Additional Time to Comment

One commenter (0505) stated that the proposed monitoring and testing requirements for the 

various kiln configurations are very complex and will need additional time for the commenter’s 

consideration beyond the length of the comment period. The commenter requests that EPA be 

open to receiving additional comments on these requirements in the coming months.

Response: See response 3.35 above.

4.59 Coal Mills/Alkali Bypass: Promulgation of Coal Mill Requirements would be 

Unlawful

One commenter (0505) stated that the proposed monitoring and testing requirements are 

confusing. EPA appears to be suggesting all sorts of complex provisions for some cement plant 

coal mills with no data in the record to support these complex provisions. EPA states that it has 

no information on how many sources its proposal might be impacting. Although the proposed 

rule includes regulatory language in the proposed rule, EPA states in the preamble: “Though we 

are not proposing the coal mill requirements in this action, we have placed the appropriate 

regulatory text in the proposed rule language to allow comment on actual rule language.”

The commenter stated that they cannot understand why EPA is including the discussion about 

coal mills in the proposal, when they clearly state that it is not proposing coal mill requirements. 

With EPA‘s statement that it not proposing coal mill requirements in the July 18 Federal 

Register notice, it could not legally finalize any such requirements without a new proposed rule 

in accordance with Administrative Procedure Act and CAA §307(d) rulemaking requirements 

and be based on data and information on which sources would be affected by various proposed 

requirements.

Response: See response 3.35 above. Moreover, EPA has held a number of follow-up meetings 

with industry representatives on this issue, providing further notice and opportunity for

comment. See Docket items EPA-HQ-OAR-2011-0817-0196, 0612, 0828. EPA notes in 

addition that the provisions are not emission standards but rather means of accounting for 

commingled emissions that are already subject to emission standards. No sources need be 

affected by these provisions, since the choice whether or not to commingle coal mill and kiln 

emissions is voluntary. EPA has also calculated the (modest) impacts of the rule in assessing the 

rule’s costs and benefits. See section VI.H to the preamble to the final rule. Thus, EPA does not 

accept that there is any procedural deficiency in adopting the provisions relating to commingled 

coal mill and cement kiln emissions.
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Comment: Coal Mills/Alkali Bypass: Suggested Alternative to Testing Coal Mills

One commenter (0511) stated that EPA’s proposal to require that sources separately monitor or 

test emissions of the non-PM pollutants from coal mill vents is excessively conservative and 

expensive given, as EPA acknowledges in the preamble, that coal mills operate only 

intermittently. The commenter notes that none of the coal mills they operate are equipped with a 

flow monitor and it is not necessary to do so in order to reasonably estimate emissions based on 

those from the kiln stack. In-line coal mills using kiln gas as an indirect heat source are not 

inherent to the kiln, but are reliant upon the kiln in order to operate. The commenter stated that 

they are designed to utilize 6 to 10 percent of the kiln gas and cannot accept more than this 

amount without causing a fire in the coal mill. The commenter suggests that a reasonable means 

of addressing emissions from separately vented coal mills would be to allow sources to 

manually determine the average kiln exhaust flow routed to the coal mill as a percentage of the 

overall kiln exhaust and then monitor the operating hours of the coal mill. During those time 

periods while the coal mill is operating, the emissions measured in the main stack would be 

increased by the percentage reflecting flow attributable to the separately vented coal mill. If 

there is a change in operations that would negatively affect compliance with the mercury 

standard, the affected source would have to determine the flow rate under requirements 

comparable to those used under the D/F standards to reset the temperature parameter after 

changes. 

Response: EPA recognizes the intermittent nature of coal mills and the inherent flow constraints 

of kiln gas to the coal mill due to safety concerns and maximum design capacities. EPA agrees 

with the commenter that there are alternative methods to the use of flow monitors for 

determining the flow rate of kiln gas to separately vented coal mills. For example, the average 

kiln exhaust flow routed to the coal mill can be determined as a percentage of the overall kiln 

exhaust with knowledge of the maximum design capacity of the coal mill and the capacity at 

which it is being run. This information could be used in conjunction with monitored operating 

hours of the coal mill and the 30 month stack test results to determine mass emissions. Other 

parameters, such as degree of coal mill fan valve openings noted during a successful 

performance test, could be monitored as an indicator of a consistent flow rate. As an alternative 

to the requirement to use flow meters, the final rule allows the owner or operator to use 

parametric monitoring to insure that the flow to the coal mill will not result in an exceedance of 

the emission limits. If the owner or operator selects this approach, they must develop a plan 

demonstrating how parametric monitoring in combination with performance tests every 30 

months will ensure continuous compliance and submit the plan to their permitting authority for 

approval. Upon approval the plan must be incorporated into the facility’s operation, maintenance 

and monitoring plan.

EPA does not agree with the commenter’s suggestion that instead of monitoring emissions to 

separately vented coal mills the emissions measured in the main stack can simply be increased 

by the percentage of overall kiln exhaust going to the separately vented coal mill. The emissions 

measured in the main stack are controlled emissions. Increasing those emissions by the 

percentage reflecting flow attributable to the separately vented coal mill does not account for the 

fact that the emissions routed to the separately vented coal mill are uncontrolled. 
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4.60 Coal Mills/Alkali By-pass Stacks: Issue with Upstream Monitoring of THC 

and HCl for Co-mingled Streams

One commenter (0511) supported EPA’s proposal to allow affected sources to monitor THC 

and HCl upstream of the coal mill where a separately vented coal mill receives kiln exhaust as 

coal may contribute to these pollutants and EPA did not account for this contribution in 

establishing the standard. However, the commenter also believes that it is necessary to allow a 

source that vents coal mill emissions to a common main stack, the option to monitor THC and 

HCl upstream of the coal mill and upstream of the duct where the coal mill exhaust is 

introduced to the main stack. EPA’s data for developing the THC and HCl numbers did not take 

into account any contribution from the coal mill, EPA merely asserts that coal mill THC is 

primarily methane. 

While the commenter also believes this to be true, it is much more expensive to conduct annual 

oHAP stack tests to demonstrate the alternative compliance method when what is actually 

necessary is to characterize the kiln gas used by the coal mill prior to the gas being introduced to 

the coal mill. There is no support for counting the coal mill exhaust emissions towards 

compliance with the THC and HCl standards. Furthermore, the commenter believes it is arbitrary 

and capricious for EPA to count coal mill THC and HCl towards compliance for some sources, 

but not for other sources, based solely on how the emissions are ducted. The THC and HCl 

standards were established based on emissions from kilns. If an affected source monitors THC 

and HCl upstream of the coal mill inlet and upstream of the point in the common main stack 

where the coal mill emissions are introduced, then that source has accurately characterized the 

emissions from the kiln.

Response: We agree with the commenter and have revised the testing and monitoring 

requirements to allow testing upstream or downstream of the coal mill.

Coal Mills/Alkali Bypass: Rule Inconsistency

Comment 0511 stated that the proposed language in. 63.1343(b)(2) appears to be missing 

language allowing coal mill exhaust to be accounted for in the alternative PM standard.

Response: We have corrected this inconsistency in Section 63.1343(b)(2).

4.61 Clinker Piles: Installation of Ambient Monitors
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Commenter (0517) states that the conservative work practices proposed within the Portland 

cement rule assist the industry by reducing an overwhelming financial burden of enclosing all 

clinker piles on site. To insure that these work practices are properly protecting human health 

and the environment the commenter would like the EPA to consider and respond with 

comments to including with the clinker pile work practices a PM 10 ambient monitoring 

networks to measure HAP metals from existing and new sources. 

The commenter states that the capital cost to install a PM 10 monitoring network is far less 

burdensome than the $10-$25 million USD estimated in the rule for clinker pile enclosures. A 

PM 10 network will also consume less than the $400,000-$500,000 estimated to annually 

maintain a clinker pile enclosure. The secondary battery recycling industry has been operating 

this same type of monitoring network for years and it has proven itself to be reliable and cost 

effective. 

The commenter states that any fugitive emission impacts from the clinker piles would be 

detected by the ambient monitoring network and actions to modify and reduce the fugitive 

emissions quickly undertaken. The commenter believes EPA's Version 8.2 a free Chemical Mass 

Balance (CMB) model (EPA, 2005) should be used to analyze the data and apportionment the 

concentrations measured by the monitors and that EPA's Protocol for Applying and Validating 

the CMB Model (EPA, 1987) would allow the cement plant to use wind speed/wind direction 

and the CMB 8.2 software to locate which clinker pile was producing the fugitive emissions. 

The commenter indicates that although current PM 10 FRM could be deployed as samplers for a 

Portland cement ambient monitoring network the time delay between taking the sample and 

reporting the concentration wouldn’t allow for expeditious response to fugitive emission releases 

from clinker piles. A near-real-time monitor, which combines the sampling and monitoring into 

one instrument would be the best option for protection of human health and the environment. 

Response: The final rule includes work practice standards to be included in facilities’ operation 

and maintenance plans for approval by the appropriate permitting authority. Thus, the rule does 

not require permanent enclosures. With local oversight by permitting authorities, EPA is assured 

of compliance with emissions control.
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Section 5: Comments on Affirmative Defense

5.1 Affirmative Defense: General Support

One commenter (0505) stated that they supports EPA‘s retention of an affirmative defense. 

EPA has the legal authority to promulgate an affirmative defense for malfunctions.

One commenter (0475) stated that they agree that EPA has the authority to promulgate 

affirmative defense. However, the commenter stated that the affirmative defense criteria 

currently specified are too subjective. The commenter recommended that EPA more specifically 

define the circumstances related to a sudden, infrequent, and unavoidable failure of air pollution 

control and monitoring equipment to make the affirmative defense more useful to owners and 

operators. 

The commenter (0475) also supported EPA’s proposed revisions to § 63.1344 which delete the 

terms “short” and “severe” and add clarifying language requiring proof by a preponderance of 

the evidence that the affected source was being operated in a manner “consistent with good air 

pollution control practice for minimizing emissions.” EPA is also proposing to revise §

63.1344(b) to state that “[t]he owner or operator seeking to assert an affirmative defense shall 

submit a written report to the Administrator in a semiannual report with all necessary supporting 

documentation, that it has met the requirements set forth in § 63.1354(c) of this subpart.” The 

commenter supports the proposed revisions to S 63.1344.

Response: EPA has noted the support for the affirmative defense.

5.2 Affirmative Defense: Opposition to General Rationale

One commenter (0508) disagreed with EPA’s position that the affirmative defense meets the 

continuous compliance requirement “by ensuring that even where there is a malfunction, the 

emission limitation is still enforceable through injunctive relief.” To the contrary, the 

affirmative defense does not make injunctive relief available; it was already available under the 

CAA. All the affirmative defense does is restrict the availability of other relief. 

One commenter (0508) stated that EPA also claims it is reasonable to incorporate “flexibility” 
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into continuous compliance requirement. According to the commenter, EPA has no authority to 

alter the continuous compliance requirement at all. It is a statutory requirement, and EPA must 

implement it, not rewrite it to suit the agency’s policy preferences. 

Response: For malfunctions, the EPA is finalizing the proposed affirmative defense language for 

exceedances of the numerical emission limits that are caused by malfunctions with minor 

revisions as discussed below. As the EPA explained in the preamble to the proposed rule, the 

EPA recognizes that even equipment that is properly designed and maintained can fail and that 

such failure can cause an exceedance of the relevant emission standard. The EPA is including an 

affirmative defense in the final rule as we have in other recent section 112 and section 129 rules 

so as to balance the tension, inherent in many types of air regulation, to ensure adequate 

compliance while simultaneously recognizing that despite the most diligent of efforts, emission 

limits may be exceeded under circumstances beyond the control of the source. The EPA must 

establish emission standards that “limit the quantity, rate, or concentration of emissions of air 

pollutants on a continuous basis.” 42 U.S.C. § 7602(k)(defining “emission limitation and 

emission standard”). See generally Sierra Club v. EPA, 551 F.3d 1019, 1021 (D.C. Cir. 2008) 

(emissions limitations under CAA section 112 must both continuously apply and meet section 

112’s minimum stringency requirements, even during periods of startup, shutdown and 

malfunction). 

Thus, the EPA is required to ensure that section 112 emissions limitations are continuous. The 

affirmative defense for malfunction events meets this requirement by ensuring that even where 

there is a malfunction, the emission limitation is still enforceable through injunctive relief. While 

“continuous” limitations, on the one hand, are required, there is also caselaw indicating that in 

some situations it is appropriate for the EPA to account for the practical realities of technology. 

For example, in Essex Chemical v. Ruckelshaus, 486 F.2d 427, 433 (D.C. Cir. 1973), the D.C. 

Circuit acknowledged that in setting standards under CAA section 111 “variant provisions” such 

as provisions allowing for upsets during startup, shutdown and equipment malfunction “appear 

necessary to preserve the reasonableness of the standards as a whole and that the record does not 

support the ‘never to be exceeded’ standard currently in force.” See also, Portland Cement 

Association v. Ruckelshaus, 486 F.2d 375 (D.C.Cir. 1973). Though intervening caselaw such as 

Sierra Club v. EPA and the CAA 1977 amendments calls into question the relevance of these 

cases today, they support the EPA’s view that a system that incorporates some level of flexibility 

is reasonable. 

The affirmative defense simply provides for a defense to civil penalties for excess emissions that 

are proven to be beyond the control of the source. By incorporating an affirmative defense, the 

EPA has formalized its approach to upset events. In a Clean Water Act setting, the Ninth Circuit 

required this type of formalized approach when regulating “upsets beyond the control of the 

permit holder.” Marathon Oil Co. v. EPA, 564 F.2d 1253, 1272-73 (9th Cir. 1977). See also, 

Mont. Sulphur & Chem. Co. v. United States EPA, 2012 U.S. App. LEXIS 1056 (Jan 19, 

2012)(rejecting industry argument that reliance on the affirmative defense was not adequate). 

But see, Weyerhaeuser Co. v. Costle, 590 F.2d 1011, 1057-58 (D.C. Cir. 1978) (holding that an 
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informal approach is adequate). The affirmative defense provisions give the EPA the flexibility 

to both ensure that its emission limitations are “continuous” as required by 42 U.S.C. § 7602(k), 

and account for unplanned upsets and thus support the reasonableness of the standard as a whole. 

5.3 Affirmative Defense: Assessment of Penalties (113(e) and 304)

One commenter (0508) stated that EPA argues that “the affirmative defense ... is not relevant 

to the amount of any penalty to be assessed. If a court determines that the affirmative defense 

elements have been established, then a penalty is not appropriate and penalty assessment 

pursuant to the section 113(e)(1) factors does not occur.” According to the commenter, that 

argument is absurd; a provision that can prevent the assessment of any penalties at all is, at a 

minimum, “relevant” to penalties. 

One commenter (0508) stated that EPA also claims that where it “defines its emissions 

limitations and enforcement measures to allow a source the opportunity to prove its entitlement 

to a lesser degree of violation (not subject to penalties), penalties under § 304 are not 

“appropriate” under § 304.The commenter stated that neither the CAA nor even EPA’s own 

regulations, however, define the emission limitations to allow a source to avoid penalties. EPA 

is free to so define its own “enforcement measures,” but attempting to limit courts’ enforcement 

authority violates § 304 and §113(e)(1). In any event, there is no such thing as a “lesser degree 

of violation” under the CAA. Any violation is a violation, and Congress intended citizens to be 

able to bring enforcement actions where any violation occurs and to seek penalties in such 

actions. To be sure a court may determine that the some violations warrant smaller penalties or 

no penalties at all, but that is a decision for a court to make based on the facts before it and the 

penalty provisions in § 113(e)(1).

Response: EPA’s view is that the affirmative defense is consistent with CAA sections 113(e) 

and 304. Section 304 gives district courts jurisdiction “to apply appropriate civil penalties.” 

Section 113(e)(1) identifies the factors that the Administrator or a court shall take into 

consideration in determining the amount of a penalty to be assessed only after it has been 

determined that a penalty is appropriate. The affirmative defense regulatory provision is not 

relevant to the amount of any penalty to be assessed under section 113(e) because if a court 

determines that the affirmative defense elements have been established, then a penalty is not 

appropriate and penalty assessment pursuant to the section 113(e)(1) factors does not occur.

In exercising its authority under section 112 to establish emission standards (at a level that meets 

the stringency requirements of section 112), the EPA necessarily defines conduct that constitutes 

a violation. The EPA’s view is that the affirmative defense is part of the emission standard and 

defines two categories of violation. If there is a violation of the emission standard and the source 

demonstrates that all the elements of the affirmative defense are met, only injunctive relief is 

available. All other violations of the emission standard are subject to injunctive relief and 
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penalties. The CAA does not require that all violations be treated equally. Further, a citizen suit 

claim under section 304 allows citizens to commence a civil action against any person alleged to 

be in violation of “an emission standard or limitation under this chapter.” The CAA, however, 

allows the EPA to establish such “enforceable emission limitations.” Thus, the citizen suit 

provision clearly contemplates enforcement of the standards that are defined by the EPA. 

As a result, where the EPA defines its emissions limitations and enforcement measures to allow a 

source the opportunity to prove its entitlement to a lesser degree of violation (not subject to 

penalties) in narrow, specified circumstances, as the EPA did here, penalties are not 

“appropriate” under section 304. The EPA’s view is that an affirmative defense to civil penalties 

for exceedances of applicable emission standards during periods of malfunction appropriately 

balances competing concerns. On the one hand, citizen enforcers are concerned about additional 

complications in their enforcement actions. On the other hand, industrial sources are concerned 

about being penalized for violations caused by malfunctions that could not have prevented and 

were otherwise appropriately handled (as reflected in the affirmative defense criteria). The EPA 

has utilized its Section 301(a)(1) authority to issue regulations necessary to carry out the Act in a 

manner that appropriately balances these competing concerns.

The EPA disagrees that the affirmative defense provision will hamper citizen enforcement. First, 

injunctive relief is still available and the threat of penalties would not deter violations in cases 

where all of the conditions of the affirmative defense have been satisfied because the affirmative 

defense criteria ensure that all reasonable steps were taken to prevent a malfunction that causes 

excess emissions. Further, litigating whether a source has met the affirmative defense will not 

burden citizen group any more or less than would litigating the appropriate penalty amount in the 

penalty assessment stage of a citizen suit enforcement action, because the 113(e) penalty 

assessment criteria and the affirmative defense criteria are similar and in fact overlap. For 

example, the requirement that the Administrator or the court consider “good faith efforts to 

comply” is bound to generate the type of fact-intensive disputes that the commenter complains 

of. In addition, several of the affirmative defense criteria are exactly the type of criteria the 

Administrator or Court might consider in determining whether a source made “good faith efforts 

to comply.” For example, to take advantage of the affirmative defense, the source must prove by 

a preponderance of the evidence that, among other things, the excess emissions “were caused by 

an unavoidable failure of air pollution control and monitoring equipment, process equipment, or 

a process to operate in a normal or usual manner” and “could not have been prevented through 

careful planning, proper design or better operation and maintenance practices” and “did not stem 

from any activity or event that could have been foreseen and avoided, or planned for.”

Thus, the EPA does not expect the affirmative defense provision to significantly alter the burden 

of bringing a citizen enforcement action. For those cases that do proceed to trial, even in the 

absence of this affirmative defense, sources generally raise equitable arguments to argue for a 

low penalty and citizens often rebut such arguments. Therefore, as a practical matter, the EPA 

does not expect the affirmative defense provision to materially affect the practice of CAA 

enforcement. 
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5.4 Affirmative Defense: Burden and Duplication Issues

Commenter (0495) states that EPA should establish a work practice standard that requires pre 

determined malfunction plans with practices and procedures for potential malfunctions; require 

reasonable reporting of any malfunctions; address any malfunctions not contemplated and add 

to the plan and address as appropriate. In developing an affirmative defense to malfunctions 

(rather than setting work practice standards for those periods), EPA has inappropriately placed 

the burden on the source to prove that excess emissions were caused by a malfunction. 

Malfunctions clearly meet the CAA definition for when work practice standards are appropriate 

and EPA’s rationale for taking the affirmative defense approach in this proposal should not 

foreclose the work practice approach in other MACT standards. CAA §112(h). 

Alternatively, if EPA rejects such work practice standards and, instead, includes an affirmative 

defense for malfunctions, the terms of the defense need to be changed. First, a source should not 

have to prove it meets every criterion to successfully claim the affirmative defense. Rather, the 

different criteria should be factored in evaluating whether the excess emissions should be 

excused. 

Commenter (0495) is concerned that the affirmative defense structure proposed and implemented 

by EPA is needlessly complex and difficult for individual facilities to follow. 

Commenter (0495) indicates that the EPA proposes a streamlined reporting and notification 

requirement that eases the burden on facilities. The proposal requires that sources report 

affirmative defense claims as a part of a semi-annual report already required by the regulation. 

77 Fed. Reg. 42,400. The commenter supports this approach and encourages EPA to adapt it to 

the Boiler MACT rules still under reconsideration. In those rules, facilities are required to submit 

a separate affirmative defense report that duplicates other required reports and notifications. 76 

Fed. Reg. 80,629. The commenter supports any effort to reduce and eliminate duplicative reports 

and notifications.

Response: EPA disagrees with comments that criticize the affirmative defense for shifting the 

burden of proof. The affirmative defense does not require a facility to prove its innocence rather 

than requiring an enforcement authority to prove a violation of the CAA or change the burden of 

proof with respect to establishing a violation. The affirmative defense applies to penalties and 

thus is only utilized where a violation has been established. The burden of proof remains with the 

plaintiff in an enforcement action. See, e.g., 40 C.F.R. 22.24. If a violation has been established 

and a source wishes to assert the affirmative defense with respect to penalties, the source does 

bear the burden of establishing that the elements of the affirmative defense have been met. This 

burden-shifting is appropriate because the source is in a better position to determine the facts 

required to establish the defense. See, e.g., Arizona Pub. Serv. Co. v. EPA, 562 F.3d 1116, 1120, 

1129-30 (10th Cir. 2009) (rejecting industry challenge to the EPA’s use of an affirmative defense 
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to address excess emissions during malfunction events). 

EPA also disagrees with comments that criticize the affirmative defense criteria as being overly 

vague or unduly restrictive and complex. The EPA believes that courts are well equipped and 

often do evaluate and apply the type of criteria set forth is the affirmative defense. Many of the 

conditions were modeled after the conditions of the affirmative defense in EPA’s SIP SSM 

policy, which several states have adopted into their SIPs. (See, e.g., State Implementation Plans: 

Policy Regarding Excessive Emissions During Malfunctions, Startup, and Shutdown (Sept. 20, 

1999); Policy on Excess Emissions During Startup, Shutdown, Maintenance, and Malfunctions 

(Feb. 15, 1983)). We do not have any indication that parties to enforcement proceedings have 

had any significant difficulties applying the terms of these SIP affirmative defenses. In addition, 

the EPA’s view is that use of consistent terms in establishing affirmative defense regulations and 

policies across various CAA programs will promote consistent implementation of those rules and 

policies. 

5.5 Affirmative Defense: Rebuttable Presumption

One commenter (0506) suggested that EPA establish a rebuttable presumption (rather than 

affirmative defense) where it is presumed that any violation occurring during the malfunction 

was not the facility’s fault unless the Agency proves certain facts that are enumerated in the 

rules.

Response: With respect to the comment that the affirmative defense should be stated instead in 

terms that, once a source has claimed that its excess emissions were related to a malfunction, it 

will not be considered to be in violation of the standards unless the enforcement authority 

demonstrates that the source is not entitled to claim the malfunction, the EPA does not agree that 

the affirmative defense should operate as the commenter suggests. The commenter improperly 

seeks to shift the burden of proof from the source to the EPA. It is the source, not the EPA, that 

has the information relevant to assess whether a particular event qualifies as a malfunction and 

meets the affirmative defense.

5.6 Affirmative Defense: Suggested Revisions

One commenter (0506) stated that should the Agency keep the affirmative defense concept, 

they suggested several modifications to the language to make it more usable including: the use 

of “all;” “any activity;” the definition of “malfunction;” root cause analysis, recordkeeping, and 

use of affirmative defense for injunctive relief enforcement actions.
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Response: Many of the conditions in the affirmative defense are modeled after the affirmative 

defense in EPA’s State Implementation Plan (SIP) SSM policy, see, e.g., State Implementation 

Plans: Policy Regarding Excessive Emissions During Malfunctions, Startup, and Shutdown 

(Sept. 20, 1999); other conditions are modeled after a Federal Implementation Plan (FIP) 

promulgated by EPA (§50.1312). The EPA’s view is that use of consistent terms in establishing 

affirmative defense regulations and policies across various CAA programs will promote 

consistent implementation of those rules and policies.

5.7 Affirmative Defense: Ferroalloys MACT Comments Incorporated by 

Reference

 The SSM Coalition states that the EPA has not addressed apparent limitations and 

shortcomings of the affirmative defense, which make it an entirely inadequate substitute for 

setting MACT standards that include provisions for SSM events. The commenter states that the 

EPA has provided no analysis that would supersede its long-standing determination that it is not 

desirable to rely on enforcement, rather than regulatory language, to address the inability to 

comply with technology-based standards during SSM events.

The SSM Coalition also states that if the EPA refuses to set alternative emission standards that 

apply during SSM periods and continues to rely instead on the proposed affirmative defense, the 

affirmative defense must be substantially modified for it to provide any significant relief. First, 

the affirmative defense needs to state clearly that a source that qualifies for the affirmative 

defense shall not be deemed to have violated the applicable standards during that time. If the 

EPA does that, it may be unnecessary to state also that the affirmative defense relieves the source 

from liability for all types of penalties and injunctive relief (save criminal penalties), but that 

should be the clear effect of qualifying for the affirmative defense.

Response: The EPA disagrees that standards must be achievable during all malfunctions. The 

EPA agrees that standards must be achievable during startup and shutdown, and we have applied 

the standards applicable to normal operating conditions to periods of startup and shutdown. As 

stated previously, two sources submitting information in response to the information collection 

request sent to them as part of this rulemaking, provided information indicating that compliance 

during startup and shutdown is practicable.

As explained in the preamble to the proposed rule, the EPA has determined that CAA section 

112 does not require that emissions that occur during periods of malfunction be factored into 

development of CAA section 112 standards. The EPA's approach has been very clear that 

sources may raise an affirmative defense to penalties only, not to liability. Successful assertion of 

an affirmative defense would not exonerate a source from a violation and injunctive relief would 

be available.
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The SSM Coalition states that the EPA offers no defensible rationale for excluding startup and 

shutdown events from the proposed affirmative defense. The commenter believes that there is 

no rational basis for the EPA not to provide the same kind of affirmative defense that it 

proposes to provide for malfunctions if in fact excess emissions from those units cannot 

reasonably be avoided during a startup or shutdown, not because of failure of a process or 

equipment but because of the nature of conditions while starting up or shutting down the source.

Response: The EPA is promulgating the affirmative defense for malfunctions only, not for 

periods of startup and shutdown except that the affirmative defense would be available if there 

were a malfunction that occurs during a period of startup or shutdown. The EPA believes that 

malfunction events should be treated differently than periods of startup and shutdown, which are 

predictable and routine aspects of a source’s operations. Because startup and shutdown periods 

are part of a source’s normal operations, the same approach to compliance with, and enforcement 

of, applicable emissions standards during those periods should apply as otherwise applies during 

a source’s normal operations. Further, periods of startup and shutdown – but not malfunctions --

are taken into account when establishing section 112 emissions standards. For these reasons, the 

EPA believes it is appropriate to apply the affirmative defense based on the occurrence of a 

malfunction and not based on startup or shutdown status. Furthermore, the commenter provided 

no information to suggest that excess emissions during startup or shutdown cannot be avoided.

Felman states that, in general, the affirmative defense language should be replaced with the 

language used at 40 CFR 122.41(n), the upset defense provided under the Clean Water Act. The 

commenter adds that the language is generally too narrow and restrictive, noting that the 

proposed rules would excuse only events that do not “stem from any activity or event that could 

have been foreseen and avoided, or planned for”, while it is possible that events such as power 

failure or natural disasters may be “foreseen” and “planned for,” but still interfere with a 

facility’s ability to comply with the standards. The commenter states that these types of 

foreseeable yet unpreventable events must either be reflected in the overall MACT 

requirements, or excused as a malfunction. Felman also states that the EPA should expand the 

proposed defense to address foreseeable yet unpreventable events.

Response: The EPA disagrees with the comment that the language for affirmative defense 

proposed is too narrow. The EPA chose to use the language “foreseen and avoided...”from 

existing policy because it conveyed that certain actions or inactions have foreseeable results, 

such as improper maintenance leading to control device failure. It also conveys that while certain 

events can be foreseen and planned for, some cannot be avoided. Whether the events mentioned 

by the commenter, such as a power failure, were adequately planned for on the part of the source, 

will be the substance of an affirmative defense.
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Additionally, we do not find the commenter’s preference for the affirmative defense under the 

Clean Water Act persuasive enough to deviate from the affirmative defense approach that has 

been used under the CAA for nearly 20 years. While we recognize that certain characteristics of 

the two approaches are similar, our preference is to adopt an approach that has been practiced 

under the CAA. 

With respect to commenter’s concern that events such as power failures or natural disasters or 

other events that are foreseeable and have been planned for would not be eligible for the 

affirmative defense, the EPA believes that malfunctions that are caused by such events and that 

lead to violations could, depending on the circumstances, be eligible for the affirmative defense 

if the resulting violations could not have been prevented whether or not there was an attempt to 

plan for the event. Preparing and having a plan in place that addresses these events generally 

does not mean that all consequences of the foreseeable events can be planned for or avoided.

The SSM Coalition believes that many aspects of the affirmative defense would make it 

unavailable as a practical matter for many, if not most, malfunctions. The commenter states that 

many of these limitations on the affirmative defense also are not directly related to the question 

of whether an exceedance of the emission limitations due to a malfunction should be excused. 

The commenter adds that several of the conditions for establishing an affirmative defense in 

proposed §63.1627(a) list numerous items which may be appropriate considerations in 

determining whether excess emissions during a malfunction should be considered a violation, 

but should not to be listed as mandatory criteria. The SSM Coalition states that a number of the 

conditions for establishing an affirmative defense use phrases that are subject to a wide range of 

interpretations and that on their face do not recognize any need for reasonableness or costeffectiveness. The commenter believes that the affirmative defense, as proposed, leaves open 

the possibility that a source will be considered to be in violation because the enforcement 

authority decides subjectively that in one or more respects it would have been “proper” or 

“possible” for the source to take further steps to prevent or minimize the malfunction.

The SSM Coalition suggests modifying the affirmative defense language if it is to be retained. 

The SSM Coalition offer specific suggested language to remove ambiguity and contradictory 

language, and allow for notification via electronic communication methods. Specific comments 

regarding the affirmative defense criteria follow:

• Notification Requirements: Felman states that availability of the affirmative defense 

should not be negated by a failure to notify, especially for events with small emissions. 

The commenter adds that the immediate notification requirements are duplicative of 

notification requirements under other rules, but do not include emission threshold triggers 

which reduce the burden of the other requirements. 

• Infrequent Events: Felman states that restricting the malfunction defense to “infrequent” 

events is legally acceptable only if more “frequent” events are either included within the 

99% UPL or excepted under some version of the startup/shutdown defense. The 
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commenter adds that determining whether the event is sufficiently “infrequent” to merit 

application of the defense is highly subjective and vague and does not put Felman on 

notice of the type of behavior that is necessary to comply with the law.

• Off-Shift and Overtime Labor: The commenter requests that the EPA delete the 

requirement to use off-shift and overtime labor because it impairs the ability to respond in 

a manner that is most appropriate to the circumstances.

• Severe Property Damage: According to the commenter, the word “severe” should be 

removed from the requirement for measure of property damage due to its ambiguity.

• Signed Operating Logs: The commenter states that the requirement for “signed” 

operating logs should be removed because it conflicts with the common practice of using 

electronic logs.

• Control Systems Were Kept In Operation “If at All Possible”: The SSM Coalition states 

that the proposed §63.1627(a)(6) requires, as a condition for the affirmative defense, that 

all emissions “control systems were kept in operation if at all possible.” The commenter 

believes that the phrase “if at all possible” should not be used because it is an extreme 

term that bears no relation to good air pollution control practices. Additionally, the 

commenter believes that this provision should be qualified, as the EPA has qualified 

similar provisions in the NESHAP General Provisions in §63.6.

• By Passing Control Equipment: The SSM Coalition is also against the proposed 

§63.1627(a)(4) that would preclude a facility from taking advantage of the affirmative 

defense if the malfunction involved bypassing control equipment or a process and the 

bypass was not “unavoidable to prevent loss of life, severe personal injury, or severe 

property damage.” The commenter states that this language is stated in such strong terms 

that it may be difficult or impossible for a source to demonstrate that it meets this 

criterion, even though bypassing the control equipment or the process was an appropriate 

exercise of good air pollution control practices. The commenter adds that there is nothing 

inherent to standards under CAA section 112 that requires a source to avoid bypassing 

control equipment to such a degree. Lastly, the commenter states that it is not apparent, 

and the EPA has not attempted to explain, why the CAA would disfavor bypassing “a 

process” in this way.

• Excess Emissions: The SSM Coalition also believes the paragraph in proposed 

§63.1627(a)(5) should be eliminated: “All possible steps were taken to minimize the 

impact of the excess emissions on ambient air quality, the environment and human 

health.” In addition to the subjective term “all possible steps,” the commenter believes 

this provision again presents a disconnect between the absolute and extreme requirement 

of the affirmative defense and the provisions of the CAA designed to attain ambient air 

quality standards and protect human health and the environment. The commenter states 

that the CAA does not require sources to take “all possible steps” to control emissions, 

even to minimize the impact of hazardous air pollutant emissions on human health under 

CAA section 112(f). In addition, the commenter finds it is unclear how this criterion for 

qualifying for the affirmative defense differs from proposed §63.1627(a)(3) which 

requires that the frequency, amount, and duration of excess emissions “were minimized 

to the maximum extent practicable.” 

• Malfunction Report: The SSM Coalition states that the provision in the Proposed Rule for 

requesting and obtaining an extension of the reporting deadline of up to 30 days would 

provide little practical relief. The commenter explains that the source would have to 
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submit the report within 45 days unless the EPA Administrator granted the extension 

request before the expiration of the initial 45-day period, which is not likely to happen 

until shortly before, if not after, the report would otherwise be due. At a minimum, the 

commenter recommends the rule should provide that a request for extension of the 

reporting deadline that the Agency has not acted on within 10 days is considered granted.

Response: The EPA disagrees with comments that state that the affirmative defense is 

unavailable as a practical matter for many, if not most malfunctions. The EPA believes that 

courts are well equipped and often do evaluate and apply the type of criteria set forth is the 

affirmative defense. Many of the conditions were modeled after the conditions of the affirmative 

defense in the EPA’s SIP SSM policy, which several States have adopted into their SIPs. (See, 

e.g., State Implementation Plans: Policy Regarding Excessive Emissions During Malfunctions, 

Startup, and Shutdown (Sept. 20, 1999); Policy on Excess Emissions During Startup, Shutdown, 

Maintenance, and Malfunctions (Feb. 15, 1983)). The EPA does not have any indication that 

parties to enforcement proceedings have had any significant difficulties applying the terms of

these SIP affirmative defenses. In addition, the EPA’s view is that use of consistent terms in 

establishing affirmative defense regulations and policies across various CAA programs will 

promote consistent implementation of those rules and policies.

The EPA has considered the commenter’s suggestions associated with specific affirmative 

defense criteria and changes. Although not all of the changes were accepted, some are reflected 

in recent changes the EPA has made to these provisions:

• Notification Requirements: The EPA has removed the requirement to notify the EPA 

within 2 days of violation of a standard in order to be able to avail themselves to a claim 

for affirmative defense. Instead, the final rule requires the source to submit a written 

report to the Administrator in the first periodic compliance, deviation report or excess 

emission report otherwise required after the initial occurrence of the violation of the 

relevant standard (which may be the end of any applicable averaging period). If such 

compliance, deviation report or excess emission report is due less than 45 days after the 

initial occurrence of the violation, the affirmative defense report may be included in the 

second compliance, deviation report or excess emission report due after the initial 

occurrence of the violation of the relevant standard.

• Infrequent Events: The EPA believes that if malfunctions occur on a frequent basis that 

the basis for the malfunction more likely falls in the categories of poor design, poor 

operational decision making, or failure to operate a source in a normal manner and has 

retained the word “infrequent” in this criteria element. 

• Off-Shift and Overtime Labor: Refer to Comment 7.5: The regulation requires that to 

establish the affirmative defense the owner must prove by a preponderance of the evidence 

that repairs were made as expeditiously as possible when a violation occurs. In light 

comment 7.5,, we have re-evaluated the language concerning the use of off-shift and 

overtime labor to the extent practicable and believe that the language is not necessary. 

Although we believe that use of off-shift or overtime labor could be cited as evidence that the 
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owner or operator expedited repairs, we do not believe this level of detail is necessary in the 

regulatory text. 

• Severe Property Damage: The EPA believes that a bypass of control equipment or a 

process, which results in a violation, should be an exception and not undertaken lightly, 

and has maintained the word “severe” in this criteria. 

• Signed Operating Logs: As an alternative, the EPA accepts electronically signed 

operating logs where the format and method of submission meets the regulatory criteria 

and are compatible with the EPA and the delegated authorities’ electronic submission 

systems. Any source submitting records electronically should exercise due diligence to 

assure receipt by the EPA and the delegated authority.

• Control Systems Were Kept in Operation “If at All Possible”: The EPA does not agree 

with the commenters’ belief that the phrase “if at all possible” should not be used because 

it is an extreme term that bears no relation to good air pollution control practices or that 

the provision needs to be qualified. The EPA does not agree with the comment because 

the phrase “if at all possible” was qualified in the proposal. The full statement is “All 

emissions monitoring and control systems were kept in operation if at all possible, 

consistent with safety and good air pollution control practices;...”(See Federal Register / 

Vol. 76, No. 226 / Wednesday, November 23, 2011 / Proposed Rules 72554)

• By Passing Control Equipment: We maintain that bypassing control equipment or a 

process should only occur when it is “unavoidable to prevent loss of life, severe personal 

injury, or severe property damage.” CAA section 112 requires continuous compliance 

with the standard and therefore avoiding bypassing a control device that is in place to 

meet a standard under the CAA is inherent to standards under CAA section 112. We also 

believe that it is not unreasonable to require a source to provide a basis for bypassing a 

control device if a source does so for safety concerns. 

• Excess Emissions: The EPA disagrees with the commenter, but points out that sources 

are only required to minimize emissions to the level allowed during normal operations, 

during periods of malfunction. Sources are not required to reduce emissions below that 

level or reduce emissions more than is required by the standards during malfunctions.

• Affirmative Defense Report: The EPA has eliminated the requirement for a 45-day 

malfunction report in the final rule. Instead, the final rule allows owners or operators 

seeking to assert an affirmative defense to demonstrate, with all necessary supporting 

documentation (as was required under the proposed 45-day report), that it has met the 

affirmative defense in an affirmative defense report to be included in the first periodic 

compliance, deviation report or excess emission report otherwise required after the initial 

occurrence of the violation of the relevant standard (which may be the end of any 

applicable averaging period). If such compliance, deviation report or excess emission 

report is due less than 45 days after the initial occurrence of the violation, the affirmative 

defense report may be included in the second compliance, deviation report or excess 

emission report due after the initial occurrence of the violation of the relevant standard.

Commenter (0505) stated that while they support the adoption of an affirmative defense for 

malfunctions, they have concerns with aspects of the defense EPA has proposed. The detailed 

provisions of the proposed affirmative defense are virtually identical to provisions EPA has 

recently been proposing in other related CAA rules. Thus, the concerns which the commenter 
134

previously expressed with respect to those rules continue to apply here. 

More specifically, on January 31, 2012, an ad hoc coalition of eighteen trade associations and 

business organizations – the “SSM Coalition” – filed comments on the SSM provisions of the 

ferroalloys proposed MACT rule. The SSM Coalition‘s comments are included with these 

comments as Appendix F. The commenter has reviewed these comments and endorses them, and 

hereby incorporates them by reference into these comments.

Commenter (0505) stated that the first preference now, consistent with the SSM Coalition‘s 

comments, is that EPA authorize work practices to apply during periods of malfunctions to meet 

the affirmative defense. As the SSM Coalition notes by way of example, “there are work 

practices – such as monitoring operating parameters to identify a malfunction and stopping or 

cutting back the process accordingly – that represent the best practices for minimizing emissions 

during a malfunction.” 

Response: The EPA may set standards, be they numerical emission limits or work practices, to 

regulate emissions during startup, shutdown, and normal operation. The EPA is not required or 

directed by the CAA to address emissions from malfunctions by setting standards applicable to 

periods of malfunction. Neither Section 111 nor Section 112 include language directing that the 

Agency account for emissions due to malfunction when setting standards under these sections. 

Affirmative Defense: Frequency

One commenter (0505) stated that if EPA were to continue with the affirmative defense 

approach, however, we believe the currently-formulated version is excessively cumbersome and 

unworkable. The SSM Coalition‘s comments address problems with the proposed language. 

Commenter (0505) highlights just a few of these points and add some of our own: 

1. The provision is set up at the outset as a mechanism to be used “in response to an action to 

enforce.” § 63.1344, introductory paragraph. Yet for a party to qualify for the defense, the party 

must submit notifications to EPA almost immediately after a malfunction occurs, and submit 

voluminous detailed written reports to EPA within 45 days after the malfunction. § 63.1344(b). 

We believe that this is essentially “putting the cart before the horse,” and doing so in an 

unwieldy manner. As EPA has enforcement discretion and many malfunctions may be brief and 

inconsequential, one might reasonably expect that many malfunctions may never become the 

subject of an enforcement action. It is not reasonable to require a facility to go through such 

immediate notice and burdensome reporting when it may have good reason to believe that an 

enforcement action may never be brought. 
135

This immediate notice and quick development of extensive written reports appears to have its 

roots in the “force majeure” provisions of EPA‘s enforcement consent decrees. In the context of 

such decrees, the requirements can make sense, as the defendant will be seeking EPA‘s approval 

to extend compliance deadlines and time will be of the essence. The statute of limitations for 

bringing an enforcement action, however, is generally five years. These immediate notice and 

quick written report requirements simply make no sense in the affirmative defense for 

malfunction context. The commenter stated that EPA should require malfunction reports each six 

months. Then, if and when EPA might decide to initiate an enforcement action, the substantive 

elements of the defense could come into play. 

Response: The EPA has evaluated some of the affirmative defense criteria, and is revising both 

the immediate notification and 45-day malfunction report. Instead, the final rule allows owners 

or operators seeking to assert an affirmative defense to demonstrate, with all necessary 

supporting documentation (as was required under the proposed 45-day report), that it has met the 

affirmative defense criteria by submittal of the affirmative defense report in the first periodic 

compliance, deviation report, or excess emission report otherwise required after the initial 

occurrence of the violation of the relevant standard (which may be the end of any applicable 

averaging period). If such compliance, deviation report, or excess emission report is due less 

than 45 days after the initial occurrence of the violation, the affirmative defense report may be 

included in the second compliance, deviation report, or excess emission report due after the 

initial occurrence of the violation of the relevant standard. This change provides sources with 

sufficient time to demonstrate that they have met the required affirmative defense criteria.

5.8 Affirmative Defense: Opposition to Independent Mandates to Qualify for the 

Defense

2. One commenter (0505) stated that the litany of factors that must all be proven without 

exception could make the defense almost impossible to meet, even where it is clear that the 

malfunction occurred at a well-maintained plant and the operator took all reasonable steps to 

avoid it and correct it expeditiously. The commenter agrees with the SSM Coalition‘s comments 

that these numerous factors should be listed as relevant criteria to be considered and weighed on 

a case-by-case basis, but that they should not be independent mandates to qualify for the 

defense. 

Response: The EPA believes the affirmative defense criteria are well-defined and will assist 

EPA and the courts in making reasoned determinations as to the establishment of affirmative 

defenses. The EPA and the courts have expertise and experience in evaluating and applying 

criteria such as those for the affirmative defense. As noted above, many of the conditions were 

modeled after the conditions of the affirmative defense in EPA’s SIP SSM policy, which several 

states have adopted into their SIPs. We do not have any indication that parties to enforcement 

proceedings have had any significant difficulties applying the terms of these SIP affirmative 

defenses. 
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5.9 Affirmative Defense: Bypassing Control Equipment

3. One commenter (0505) stated that a particularly egregious requirement being proposed is § 

63.1344(a)(4), where a malfunction related to bypassing control equipment cannot qualify for 

the defense unless “the bypass was unavoidable to prevent loss of life, personal injury, or severe 

property damage.” There may be many types of situations where good air pollution control 

practice would dictate temporary bypass of control equipment that would not rise to avoidance 

of killing, maiming, or destruction, so the standard set by this language is extreme overkill. 

Response: Many of the conditions in the affirmative defense are modeled after the affirmative 

defense in EPA’s State Implementation Plan (SIP) SSM policy, see, e.g., State Implementation 

Plans: Policy Regarding Excessive Emissions During Malfunctions, Startup, and Shutdown 

(Sept. 20, 1999); other conditions are modeled after a Federal Implementation Plan (FIP) 

promulgated by EPA (§50.1312). The EPA’s view is that use of consistent terms in establishing 

affirmative defense regulations and policies across various CAA programs will promote 

consistent implementation of those rules and policies.

The EPA believes the affirmative defense criteria are well-defined and will assist EPA and the 

courts in making reasoned determinations as to the establishment of affirmative defenses. The 

EPA and the courts have expertise and experience in evaluating and applying criteria such as 

those for the affirmative defense. As noted above, many of the conditions were modeled after the 

conditions of the affirmative defense in EPA’s SIP SSM policy, which several states have 

adopted into their SIPs. We do not have any indication that parties to enforcement proceedings 

have had any significant difficulties applying the terms of these SIP affirmative defenses. The 

EPA considers the affirmative defense criteria to be clearly subordinate to safety and good air 

pollution control practices by defining that the actions must be “consistent with” these practices.

5.10 Affirmative Defense: Root Cause

One commenter (0505) stated that the requirement to prepare and file a detailed “root cause” 

report is, as pointed out by the SSM Coalition in many respects illogical and unworkable. If a 

malfunction is, as EPA states “unavoidable” and “unforeseeable,” in many situations a facility 

may simply not be able to determine the “root cause” of the malfunction. If indeed the facility 

has taken all reasonable steps to respond and correct the situation, it would be inconsistent with 

the very concept of malfunction to deny the defense to a party who is unable to pinpoint the 

“root cause” in a report.

Response: In the context of this rule, the term “root cause analysis” was used generically to 

imply an analysis of sufficient depth and complexity to indicate whether a malfunction did 

indeed cause a failure to meet a standard, provide sufficient information on the nature and cause 
137

of a malfunction to determine whether the source had a malfunction that met the definition of a 

malfunction, and whether civil penalties are an appropriate sanction for the violation if one 

occurred. The term “root cause analysis” is not defined in subpart A (the GP) or in the subpart

being promulgated. The EPA did not intend to prescribe a specific methodology, given that “root 

cause analysis” is not a defined term in the applicable subparts of part 63.

While conducting an analysis of every malfunction may be a “best practice,” for regulatory 

purposes, an analysis is only required for those malfunctions for which the source chooses to 

assert an affirmative defense, and not every malfunction is significant enough to warrant the 

assertion. The EPA believes that sources seeking to minimize emissions will endeavor to 

determine what went wrong anytime there is a minor or major malfunction, and the facility 

should decide what level of investigation is needed in each instance.

Comment: The SSM Coalition states that the requirement in proposed §63.1627(a)(9) that the 

source “have prepared a written root cause analysis to determine, correct and eliminate the 

primary causes of the malfunction and the excess emissions resulting from the malfunction 

event at issue” again does not implement the statutory criteria for standard-setting under section 

112. The commenter is concerned that read literally it would mean that a source could never 

take advantage of the affirmative defense if the source was unable to determine the primary 

cause of the malfunction or was unable to correct that cause. The EPA has defined a 

malfunction as an event that is “unavoidable” and unforeseeable, and “not reasonably 

preventable.” It therefore should be expected that in many cases the primary cause(s) of the 

malfunction will not be ascertainable, or it will not be possible to identify a way to ensure the 

malfunction will not recur. In addition, the commenter is concerned that requiring the facility to 

eliminate the primary causes of the malfunction, without regard to “taking into consideration the 

cost of achieving such” elimination and the “non-air quality health and environmental impacts 

and energy requirements” associated with its elimination is unreasonable and entirely 

inconsistent with the criteria for standards established under CAA section 112(d). 

Felman states that the requirement to perform a root cause analysis is vague and does not put 

Felman on notice of the type of analysis that the EPA will deem sufficient, or the time in which 

such an analysis must be performed. According to the commenter, such an analysis is also 

unnecessarily burdensome and serves no environmental protection purpose for many malfunction 

events where the “root cause” is clearly identifiable (e.g., power outage, hurricane).

The CRWI asserts that the EPA’s use of the term “root cause analysis” implies a specific formal 

process. The commenter notes that for many malfunctions, the cause is immediately obvious and 

a formal process for determining the cause is not needed. The commenter adds that a formal root 

cause analysis is typically limited to very significant events or repeat events (e.g., the first time a 

thermocouple fails, the most likely cause is a bad thermocouple, but if a second one fails within a 

short period of time, then something else may be causing that event to happen and a more 

detailed analysis may be needed.) The commenter adds that the proposed language assumes that 
138

all malfunctions are equally significant and need an identical degree of investigation (e.g., a 

missing data point due to a malfunction of the data acquisition system is not as significant as a 

power failure or a catastrophic event such as fire or explosion). The CRWI believes that a formal 

root cause analysis should only be used when other reasonable methods fail to show what caused 

the malfunction or when the serious nature of an event might make such an analysis necessary. 

The commenter states that other tools may be more appropriate (e.g., failure mode and effect, 

fault tree, etc.) or more powerful tools may be introduced in the future. The commenter 

concludes that the facility is the only one that can and should decide what tool to use to 

determine the cause of the malfunction. 

The commenter states that if the EPA intends for the facility to investigate and fix the source of 

the malfunction so that it is less likely to recur, the CRWI supports that concept but suggests that 

the Agency use an alternative term that does not carry a specific meaning. However, if the 

Agency envisions a formal process for determining the root cause for every malfunction, no 

matter how simple, the CRWI believes this is unnecessary and would result in excess efforts with 

no environmental gains.

Response: The EPA believes that a minor administrative burden will result in sources analyzing 

their violative emissions to reduce or avoid those emissions in the future, which is an 

environmental benefit. A root cause analysis is only required if a source seeks to assert an 

affirmative defense. However, such an analysis is beneficial in resolving or preventing violations 

and excess emissions whether the source seeks to assert the affirmative defense or not. A root 

cause analysis is one example of what constitutes good air pollution control practices to 

minimize emissions. A root cause analysis is not required for every malfunction - - only those 

malfunctions for which the source chooses to assert an affirmative defense. We agree with the 

commenter that not every malfunction is so significant that it would require asserting an 

affirmative defense. The EPA believes that sources seeking to minimize emissions will endeavor 

to find out what went wrong anytime there is a minor or major malfunction. The facility should 

decide what level of investigation is needed in each instance. We agree with the commenter that 

sources should use appropriate techniques of analysis to achieve the desired results and 

conclusions in the event of a malfunction. The EPA joins the commenter in seeking meaningful 

results which successfully identify, and address the cause of the malfunction. However, if the 

malfunction rises to the level of one that the source seeks to avail themselves of the affirmative 

defense, then a root cause analysis is required. In the context of part 63 section 112, the term 

“root cause analysis” was used generically to imply an analysis of sufficient depth and 

complexity to indicate whether a malfunction did indeed cause a failure to meet a standard, 

provide sufficient information on the nature and causes of a malfunction to determine whether 

the source had a malfunction that met the definition of a malfunction, and whether civil penalties 

are an appropriate sanction for the violation, if one occurred. The term “root cause analysis” is 

not defined in subpart A (the General Provisions) or in the subpart being promulgated, subpart 

LLL. The EPA did not intend to prescribe a specific methodology, given that “root cause 

analysis” is not a defined term in the applicable subparts of Part 63. 
139

A root cause analysis is not mandatory and is only required if a source seeks to assert an 

affirmative defense. However, such an analysis is beneficial in resolving or preventing violations 

and excess emissions whether the source seeks to assert the affirmative defense or not. A root 

cause analysis is one example of what constitutes good air pollution control practices to 

minimize emissions. A root cause analysis is not required for every malfunction, as specified 

above, and is only required for those malfunctions for which the source chooses to assert an 

affirmative defense.

With respect to commenter’s concern that certain events such as power outages or earthquakes 

would not require a root cause analysis to determine the cause of a malfunction, the EPA again 

reiterates that not all malfunctions will require the same level of analysis to determine the cause 

of the event. The EPA understands that some malfunctions will be relatively straightforward to 

analyze for the purpose of determining the basic cause of the event, and submittal of the analysis 

that addresses the criteria of the affirmative defense, will fulfill the requirement to assert an 

affirmative defense. 

The EPA believes it has provided clear criteria within the affirmative defense provisions to 

support the development of an affirmative defense report. Additionally, the EPA believes that 

these provisions will result in a minor administrative burden, but will result in sources analyzing 

their violation emissions to reduce or avoid those emissions in the future, which is an 

environmental benefit. A root cause analysis is not mandatory and is only required if a source 

seeks to assert an affirmative defense. However, such an analysis is beneficial in resolving or 

preventing violations and excess emissions whether the source seeks to assert the affirmative 

defense or not. A root cause analysis is one example of what constitutes good air pollution 

control practices to minimize emissions. A root cause analysis is not required for every 

malfunction, as specified above, and is only required for those malfunctions for which the source 

chooses to assert an affirmative defense.

Comment: The CRWI expresses concern that labeling malfunctions as an affirmative defense 

before it has been established to be a deviation improperly shifts the burden to the facility. The 

commenter suggests that the EPA should establish a rebuttable presumption where it is 

presumed that the facility did everything in their power to minimize emissions during 

malfunctions, unless the Agency proves certain facts that are enumerated in the rules, allowing 

the Agency to challenge the alleged deviation without compromising the legal rights of either 

party. 

The SSM Coalition states that even if the proposed affirmative defense were not unreasonably 

restrictive, being able to assert a defense obviously is not the same as complying with emission 

limitations that are properly set in accordance with CAA section 112. The commenter believes 

that the affirmative defense places the source in the position of proving its innocence, rather than 

the EPA or another enforcement authority having to prove that the source violated the CAA. 
140

The commenter also finds it unclear where the EPA finds the legal authority in the CAA to shift 

the burden to the regulated community of proving (or disproving) essential elements of an 

alleged violation. The commenter states that the EPA has not provided any statutory authority for 

requiring a source to prove its innocence, including fully demonstrating its innocence within 45 

days of the event, without even being charged. 

Response: The EPA disagrees with comments that criticize the affirmative defense for shifting 

the burden of proof. The affirmative defense does not require a facility to prove its innocence 

rather than requiring an enforcement authority to prove a violation of the CAA or change the 

burden of proof with respect to establishing a violation. Further, the EPA does not presume a 

violation unless the reporting requirements are met as the commenter suggests. An affirmative 

defense to civil penalties for exceedances of emission limits that are caused by malfunctions is 

available to a source owner or operator, but the decision to use the affirmative defense and meet 

the reporting and recordkeeping requirements rests with the source owner or operator, who must 

weigh the cost of meeting the requirements against their perceived need to prepare for assertion 

of an affirmative defense if a violation is established. The affirmative defense applies to 

penalties; thus it is only used where a violation has been established. The burden of proof 

remains with the plaintiff in an enforcement action. See, e.g., 40 C.F.R. 22.24. If a violation has 

been established and a source owner or operator wishes to assert the affirmative defense with 

respect to penalties, the source owner or operator bears the burden of establishing that the 

elements of the affirmative defense have been met. This burden-shifting is appropriate because 

the source owner or operator is in a better position to determine the facts required to establish the 

defense. See, e.g., Arizona Pub. Serv. Co. v. EPA, 562 F.3d 1116, 1120, 1129-30 (10th Cir. 

2009) (rejecting industry challenge to the EPA’s use of an affirmative defense to address excess 

emissions during malfunction events).

Our judgment is that the affirmative defense criteria capture the appropriate considerations in 

determining whether penalties are appropriate when a violation occurs as the result of a 

malfunction. Many of the conditions were modeled after the conditions of the affirmative 

defense in the EPA’s SIP SSM policy, which several states have adopted into their SIPs. (See, 

e.g., State Implementation Plans: Policy Regarding Excessive Emissions During Malfunctions, 

Startup, and Shutdown (Sept. 20, 1999); Policy on Excess Emissions During Startup, Shutdown, 

Maintenance, and Malfunctions (Feb. 15, 1983)). We do not have any indication that parties to 

enforcement proceedings have had any significant difficulties applying the terms of these SIP 

affirmative defenses.

Comment: The SSM Coalition believes it is not clear what the affirmative defense covers. 

According to the commenter, where the EPA states that the affirmative defense is “to a claim 

for civil penalties for exceedances of such standards that are caused by malfunction, as defined 

in §63.2,” the term “civil penalties,” is ambiguous. The commenter states that it is also unclear 

how the affirmative defense would apply to enforcement actions by State and local 

governments, or to private citizen enforcement actions under CAA section 304. 
141

The commenter also states that the preamble to the Proposed Rule does not give any explanation 

for why the affirmative defense would not apply to injunctive relief. The commenter states, as a 

matter of law, injunctive relief may not be available in cases where a civil penalty cannot be 

imposed. The commenter adds that maintaining liability for injunctive relief renders the 

affirmative defense particularly ineffective with respect to citizen suits. According to the 

commenter, if the source is even potentially subject to injunctive relief, and therefore could be 

required to pay the citizen-plaintiff’s attorneys fees even if the source successfully demonstrated 

that it otherwise qualified for the affirmative defense, then the affirmative defense would not 

accomplish the EPA’s stated objective of providing relief in situations where the emission 

limitations cannot be met despite proper design and operation of process and control equipment.

The commenter believes, at a minimum, the EPA should state that the affirmative defense 

applies to civil penalties, civil administrative penalties, noncompliance penalties, and injunctive 

relief, in an action brought by the EPA, a state, or a citizen-suit plaintiff. The commenter adds 

that the EPA also should reword the “affirmative defense,” so that it states that a source “will not 

be deemed in violation of” the MACT standards for excess emissions or other deviations from 

the standards, associated with a startup, shutdown, or malfunction event, unless the event, and 

the source’s response to the event, do not meet the criteria spelled out in the regulations. The 

commenter suggests this provision for malfunction should be called something other than an 

“affirmative defense,” such as an “alternative standard for SSM events.”

Response: The EPA’s view is that the affirmative defense is consistent with CAA sections 

113(e) and 304. Section 304 gives district court’s jurisdiction “to apply appropriate civil 

penalties.” Section 113(e)(1) identifies the factors that the Administrator or a court shall take into 

consideration in determining the amount of a penalty to be assessed only after it has been 

determined that a penalty is appropriate. The affirmative defense regulatory provision is not 

relevant to the amount of any penalty to be assessed under section 113(e) because if a court 

determines that the affirmative defense elements have been established, then a penalty is not 

appropriate and penalty assessment pursuant to the section 113(e)(1) factors does not occur.

In exercising its authority under section 112 to establish emission standards (at a level that meets 

the stringency requirements of section 112), the EPA necessarily defines conduct that constitutes 

a violation. The EPA’s view is that the affirmative defense is part of the emission standard and 

defines two categories of violation. If there is a violation of the emission standard and the source 

demonstrates that all the elements of the affirmative defense are met, only injunctive relief is 

available. All other violations of the emission standard are subject to injunctive relief and 

penalties. The CAA does not require that all violations be treated equally. Further, a citizen suit 

claim under section 304 allows citizens to commence a civil action against any person alleged to 

be in violation of “an emission standard or limitation under this chapter.” The CAA, however, 

allows the EPA to establish such “enforceable emission limitations.” Thus, the citizen suit 

provision clearly contemplates enforcement of the standards that are defined by the EPA. As a 

result, where the EPA defines its emissions limitations and enforcement measures to allow a 

source the opportunity to prove its entitlement to a lesser degree of violation (not subject to 
142

penalties) in narrow, specified circumstances, as the EPA did here, penalties are not 

“appropriate” under section 304.

The EPA’s view is that an affirmative defense to civil penalties for exceedances of applicable 

emission standards during periods of malfunction appropriately balances competing concerns. 

On the one hand, citizen enforcers are concerned about additional complications in their 

enforcement actions. On the other hand, industrial sources are concerned about being penalized 

for violations caused by malfunctions that could not have prevented and were otherwise 

appropriately handled (as reflected in the affirmative defense criteria). The EPA has utilized its 

Section 301(a)(1) authority to issue regulations necessary to carry out the Act in a manner that 

appropriately balances these competing concerns.

The affirmative defense applies to civil penalties, including civil administrative penalties and 

penalties under section 120, but does not apply to injunctive relief or criminal penalties. The 

affirmative defense is available in any civil action to enforce the standards set forth in this rule, 

whether such action is brought by the EPA, a state or local authority or a citizen. The EPA agrees 

that in some cases, injunctive relief may not be appropriate if all the criteria of the affirmative 

defense have been satisfied. In such cases, liability for attorney’s fees is not a real issue. 

However, some form of injunctive relief may be appropriate. The affirmative defense is not a 

time-bar to civil penalties. The EPA does not intend to provide an affirmative defense to criminal 

charges as the very nature of criminal charges is that there is alleged to be a knowing violation 

(CAA Section 113(c)(1-3), or a knowing or negligence release that threatens imminent danger to 

persons (CAA Section 113(c)(4)and (5)). In these circumstances, it is likely that the source did

not do all that could be done to prevent the excess emissions. However, if there are 

circumstances that justify a knowing release as is suggested by the commenter, such 

circumstances can be raised in any enforcement action and may be the basis for a defense.

The EPA reminds the commenter that the EPA must establish emission standards that “limit the 

quantity, rate, or concentration of emissions of air pollutants on a continuous basis.” 42 U.S.C. 

7602(k) (defining “emission limitation and emission standard”). See generally Sierra Club v. 

EPA, 551 F.3d 1019, 1021 (D.C. Cir. 2008) (emissions limitations under CAA section 112 must 

both continuously apply and meet section 112’s minimum stringency requirements, even during 

periods of startup, shutdown and malfunction). Thus, the EPA is required to ensure that section 

112 emissions limitations are continuous. The affirmative defense for malfunction events meets 

this requirement by ensuring that, even where there is a malfunction, the emission limitation is 

still continuous by being enforceable through injunctive relief.

The affirmative defense is available in any action to enforce the standards set forth in this rule, 

whether such action is brought by the EPA, a state or local authority or a citizen. Although the 

preamble‘s reference to the “Administrator” may have caused some confusion, there is nothing 

in the language of the regulatory text establishing the affirmative defense that suggests that the 

affirmative defense is limited to the EPA enforcement actions.
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Section 6: Comments on Impacts of the Rule

6.1 Impacts: ACI Cost Estimate Inaccurate

One commenter (0511) stated that EPA’s cost estimate in the 2012 preamble is grossly 

inaccurate. The commenter notes that if an affected source has to consider a second ACI system 

then it is the commenter’s experience that the additional capital cost would be between $15 and 

$20 million and the annual operating cost (exclusive of capital, administrative, labor, safety or 

lab costs) of operating the ACI system is in excess of $1 million/year. The commenter believes 

the costs associated with moving to a beyond-the-floor limit are considerably more than what 

EPA estimated in the 2012 preamble. The commenter’s extensive experience suggests that the 

cost estimates in the 2009 rulemaking are reasonably accurate and capture the cost of 

consistently achieving a 55 lbs/million ton v. a 58 lbs/million ton limit. Based on the additional 

cost associated with reaching the beyond-the-floor limit, the commenter believes that EPA 

should maintain the limit at the floor.

Response: See response 3.14 and preamble section V.B.. 

6.2 Impacts: PM Incremental Risk to Public Health

One commenter (0525) stated that they are very concerned about the technical justification and 

scientific validity of the analysis upon which the ambient air quality standards for PM are based. 

The significant issues with scientific justification of that standard have lead to an unfortunate 

perception on the part of the public as to the perceived benefits of the rule as initially adopted 

and an equally unfortunate perception that the proposal under the reconsidered rule will 

compromise those benefits. The commenter fundamentally disagrees that this reconsideration 

represents a significant incremental risk to public health, but will address that position in 

supplemental comments within the extended comment period that will follow the public hearing 

of this date in Arlington, Texas.

The commenter continued that they support the proposed modifications to emission standards for 

PM.

Response: The ambient air quality standards for PM are not part of this rulemaking and thus a 

response to this comment has not been developed.
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Section 7: Comments Regarding Miscellaneous Other Issues

7.1 Other Issues: Request to Reorganize Rule

One commenter (0505) requested that EPA re-organize the rule requirements to once again 

place, for example, all recordkeeping requirements under one regulatory subsection. 

Recordkeeping requirements may now be found in multiple sections creating compliance 

confusion.

Response: We believe we have organized this rule in a manner that makes it as easy to read and 

understand as possible.

7.2 Other Issues: Request to Remove Flow Monitor Requirement for NSPS

One commenter (0505) stated that the requirement to install flow monitors is over-broad and 

should exclude cases where PM is the only NSPS pollutant (§ 60.63(h)). Because PM CEMS 

are no longer being applied to collect lb/hour data, flow is not required.

One commenter (0252) stated that since the proposed rule requires a PM CPMS for PM 

compliance in lieu of a PS-11 certified PM CEMS, EPA should clarify whether a stack flow rate 

monitoring system would no longer be required on a clinker cooler stack at an existing source ?

Response: We do not believe it is overly burdensome to require facilities to install stack flow 

monitors for these types of large sources. We note that only in the case of clinker coolers is there 

a situation where a mass flow rate is not required to be measured on a continuous basis. 

However, we believe that stack flow information is an important emissions parameter and may 

be useful in determining actual annual emissions for other purposes, such as annual emissions 

reporting.

7.3 Other Issues: Clarification on Averaging Periods for NSPS 

The commenter (0505) stated that the requirement to establish the operating limit based on the 

highest 1-hour average [§ 60.64(b)(iii)] should specify whether it should be derived from block 
145

averages or rolling averages.

Response: This has been clarified in the final rule.

7.4 Other Issues: Proposed Administrative Correction to § 63.1343(b)

One commenter (0505) stated that the heading of § 63.1343(b) does not include raw mills or 

finish mills, even though the requirements of the section would apply to such units. The heading 

should be revised to include these units to avoid confusion or other unintended consequences.

Response: EPA will review the proposed language in § 63.1343(b) and make changes as 

necessary.

7.5 Other Issues: Proposed Administrative Correction to § 63.1344(A)(1)(III)(2)

One commenter (0505) stated that the wording in § 63.1344(A)(1)(III)(2) implies that off-shift 

and overtime labor is required to demonstrate the affirmative defense. The language should be 

revised to reflect that these measures should be used ―as necessary to correct the malfunction 

expeditiously. 

Response: The regulation requires that to establish the affirmative defense the owner must prove 

by a preponderance of the evidence that repairs were made as expeditiously as possible when a 

violation occurs. In light of the above comment, we have re-evaluated the language concerning 

the use of off-shift and overtime labor to the extent practicable and believe that the language is 

not necessary. Although we believe that use of off-shift or overtime labor could be cited as 

evidence that the owner or operator expedited repairs, we do not believe this level of detail is 

necessary in the regulatory text. 

Other Issues: Hourly Clinker Monitoring § 63.1348(b)(1)(iv) Requirement

One commenter (0505) stated that because PM-CEMS will no longer be used to monitor 

continuous compliance on a lb/ton clinker basis, the provisions for hourly clinker monitoring [§ 

63.1348(b)(1)(iv)] should not be connected to the PM standard. This would be specifically 

applicable to hazardous waste kilns that have the cooler PM limit apply, but not to any of the 

kiln limits. In these cases, hourly clinker monitoring serves no useful purpose. Facilities should 

not be required to make costly changes to accommodate (or comply with) and unnecessary 

monitoring requirement.
146

Response: The EPA has made the requested change to the rule language. 

7.6 Other Issues: Proposed Administrative Correction to § 63.1350(k)(4)

One commenter (0505) stated that all references to performing QA procedures in conjunction 

with raw mill operations [§ 63.1350(k)(4)] need to be revised to clarify that they are only 

applicable to in-line kiln/raw mill systems.

Response: The EPA has made the requested change to the rule language

7.7 Other Issues: Proposed Administrative Correction to § 63.1350(m)(4)

One commenter (0505) stated that if the performance tests required to be conducted in order to 

establish a particular site-specific CPMS limit are not required until up to 180 days from the 

compliance date, it makes no sense why the CPMS need to be installed and operated by the 

compliance date [§ 63.1350(m)(4)]. The requirement should be revised to state that the CPMS 

need to be installed and operated by the time the initial performance test is conducted.

Response: Having the CPMS installed prior to the performance test date assures that the CPMS 

will be operational and installed properly before performance testing is required. 

Comment: Other Issues: Proposed Administrative Correction to § 63.1355(f)(ii)

One commenter (0505) stated that EPA‘s discussion of the recordkeeping requirements [§ 

63.1355(f)(ii)] does not make clear what is meant by “the type of raw feed.” This needs to be 

clarified in the final rule.

Response: Note recordkeeping requirements have been revised due to changes in startup and 

shutdown standards. Therefore this comment is moot.

7.8 Other Issues: Proposed Regulatory Text Changes, Refer to (0505) 

Appendix G

One commenter (0505) stated that they have concerns regarding the regulatory text of a number 
147

of other regulatory provisions being proposed. A detailed matrix identifying these specific 

provisions together with a discussion of our particular concerns and recommended changes to 

the regulatory text of each provision is provided with these comments as Appendix G. 

Response: Appendix G comments have been incorporated and addressed in the applicable 

sections of this document.

7.9 Other Issues: Request for Testing and Monitoring Exemptions for 

Small/Area Sources 

Commenter (0494) stated that the EPA should promulgate final revisions to the NESHAP that 

minimize the impacts on small entities and area sources. The commenter stated that the EPA 

could minimize the impact on small entities and areas sources through flexibility through costeffective testing and monitoring requirements.

Response: This comment addresses issues which were settled in the 2010 final rule, and not 

reconsidered, reopened, or otherwise reexamined here. Consequently, no response is required 

for this comment. If (against our view) a response is deemed necessary, EPA’s assessment of 

impacts on small businesses determined that 3 of the 26 existing entities were small businesses. 

Moreover, costs to such entities would be reduced as compared to the 2010 rule. For example, 

HCl CEMS are not required for sources equipped with scrubbers and those sources may use 

periodic performance testing in combination with parametric monitoring.. Also, the final rule 

does not require PM CEMS with its PS 11 requirements but instead requires sources to perform 

an annual performance test in combination with parametric monitoring. Also, the revised PM 

standard will provide additional flexibility to the industry in developing a comprehensive 

compliance strategy with many sources able to take advantage of less costly to control measures 

in order to comply with the standards.

7.10 Other Issues: Duplication of Reporting Requirements

One commenter (0506) stated that as proposed, § 63.1354(b)(9)(vi) requires facilities to report 

all PM, HCl, Hg, and THC CEMs or Hg sorbent trap 30-day rolling average data using EPA’s 

WebFIRE database. Facilities are already required to report deviations as a part of their semiannual report (see the requirements in § 63.1354(b)(9)(vii) that require the date, duration, and 

description of each deviation). It appears that requiring facilities to report daily rolling averages 

and deviations is a duplication of effort, increasing costs without any environmental benefit. 

The commenter stated that they see no reason to report daily CEMs data and suggests that EPA 

remove this requirement when promulgating the final rule.
148

Response: The EPA disagrees with the commenter that reporting the 30-day rolling averages 

from all PM, HCl, Hg, and THC CEMs or Hg sorbent trap in addition to higher measured levels

in the semi-annual report is a duplication of effort. The requirement to report excess emissions 

in §63.1354(b)(8) also requires the elements in §63.10(c)(5) – (13) to be reported in excess 

emissions reports. The elements include information such as the specific identification (i.e., the 

date and time of commencement and completion) of each time period of excess emissions and 

parameter monitoring exceedances that occurs during periods other than startups, shutdowns, and 

malfunctions of the affected source, the nature and cause of any malfunction (if known), the 

corrective action taken or preventive measures adopted, the nature of the repairs or adjustments 

to the CMS that was inoperative or out of control, and total process operating time during the 

reporting period. This information is much more specific and very different than what is 

required to be reported in §63.1354(b)(9)(vi). Thus, we are not revising these paragraphs to 

address potential duplicative reporting.

7.11 Other Issues: Comment Regarding 63.1343(a)

Commenter (0505 - Appendix G) stated "the 30-day rolling average is not defined in equations 

for Hg, THC ad HCl as it is for NOx and SO2 in NSPS for CPMS monitoring for PM. Further 

Eq. 6 for mercury is wrong. The commenter indicates that calculations would be easier, 

particularly when accounting for clinker inventory adjustments per standard business practices, 

if total mass emissions for 30 kiln operating days can be divided by total clinker production for 

30 kiln operating days." 

This comment is in reference to the following requirement: standards for mercury and THC, and 

HCl if CEMS is used, are based on 30-day rolling average. [63.1343(a)] 

Commenter states that this needs to be consistent with methodology for 30-day rolling average 

calculations. Equations should be similar to those used for NOx and SO2 (i.e. based on hourly 

data, not average of daily averages. Allow for alternate calculation by dividing total emissions 

over 30 consecutive kiln operating days by total clinker production for the same 30 kiln 

operating days.

Response: We have corrected the equation in the rule.
149

7.12 Other Issues: Comment Regarding 63.1348(a) and 63.1349(b)

Commenter (0505 - Appendix G) stated "Is this after the compliance date or at any time the 

CEMS or CPMS meets the PS even if more than 30 days prior to the compliance date? Also, 

must the alternate THC limit be determined prior to the compliance date if the first 30 days after 

the compliance date must be used? What is “consecutive”, is it “continuous”?" 

This comment is in reference to the following requirement: the first day of the 30 operating day 

performance test is the first day following completion of the field testing and data collection that 

demonstrates that the CPMS or CEMS has satisfied the relevant CPMS performance evaluation 

or CEMS performance specification acceptance criteria. The performance test period is complete 

at the end of the 30th consecutive operating day. [63.1348(a) and 63.1349(b)] 

Commenter recommends that EPA clarify that it is the first 30 operating days after the 

compliance date. Modify text: The first day of the 30 operating day performance test is the first 

day after the compliance date following completion of the field testing and data collection that 

demonstrates that the CPMS or CEMS has satisfied the relevant CPMS performance evaluation 

or CEMS performance specification acceptance criteria. The performance test period is complete 

at the end of the 30th consecutive operating day.

Response: The EPA agrees with the comment and has modified the rule text to add clarity 

regarding the effective date of compliance with the operating limits.

7.13 Other Issues: Comment Regarding 60.64(b)(2) and (3)

Commenter (0505 - Appendix G) stated "This requirement appears to require that any source, 

other than kilns, in the NSPS F source category constructed, reconstructed or modified after 

Aug. 17, 1971 is currently subject to the NESHAP monitoring requirements. These monitoring 

requirements should only apply to sources constructed, reconstructed, or modified after June 16, 

2008." 

This comment is in reference to the following requirement: for sources subject to capacity 

standards at major sources, use Method 9 and follow procedures in 63.1350(f), (m)(1) through 

(m)(4), m(10) through (11), (o) and (p). [60.64(b)(2) and (3)] 

Commenter recommends that EPA clarify that opacity monitoring requirements in NESHAP, 

referenced by NSPS F, only apply to sources constructed, reconstructed, or modified after June 

16, 2008.
150

Response: It was EPA’s intent that the modified opacity monitoring provisions apply to all 

sources subject to NSPS.

7.14 Other Issues: Comment Regarding 63.1350(f)(1)(iv)

Commenter (0505 - Appendix G) stated "Published version reads “30 opacity observations”. 

What is “30 observations”?" 

This comment is in reference to the following requirement: for other subject sources, monthly 

10-minute VEs per Method 22. If any VE observed must conduct 30 observations by Method 9, 

beginning within 1 hour. [63.1350(f)(1)(iv)] 

Commenter recommends that the following change be made: “...conduct 30 observations 

(recorded at 15-second intervals) in accordance with Method 9..."

Response: The EPA has reviewed the proposed language and has made the necessary changes to 

the rule.

7.15 Other Issues: Comment Regarding 60.64(c)

Commenter (0505 - Appendix G) stated "Calculations would be easier, particularly when 

accounting for clinker inventory adjustments per standard business practices, if total mass 

emissions for 30 kiln operating days can be divided by total clinker production for 30 kiln 

operating days."

This comment is in reference to the following requirement: calculate rolling 30 kiln operating 

day average emission per Eq. 3: Ed = (k/n)∑CiQi/Pi, where Ci is hourly concentration time in 

ppm; Qi is hourly average gas flow rate in scf/hr; Pi is total clinker produced for that hour; k is a 

conversion factor; and n is the number of kiln operating hours over the 30 kiln operating days. 

[60.64(c)] 

Commenter recommends that EPA allow for alternate calculation by dividing total emissions 

over 30 consecutive kiln operating days by total clinker production for the same 30 kiln 

operating days.

Response: We have reviewed the equations and have made the necessary corrections.
151

7.16 Other Issues: Comment Regarding 63.1343

Commenter (0505 - Appendix G) stated "Table 1 does not indicate D/F for normal operations 

(existing or new kiln) as TEQ basis." 

This comment is in reference to the following requirement: Table 1: D/F limits for normal 

operations. [63.1343] 

Commenter recommends that EPA fix Table 1.Add TEQ to Table 1 for Existing Kiln – Normal 

operation and New Kiln – Normal operation.

Response: The EPA agrees with the comment and has added TEQ to Table 1.

7.17 Other Issues: Comment Regarding 63.1350(o)(4&5)

Commenter (0505 - Appendix G) stated "Even if you submit information in a timely manner if 

the Administrator does not take action, the facility must still be in compliance. This was asked 

in Dec 2010, but it was not addressed by the EPA." 

This comment is in reference to the following requirement: alternate monitoring – Administrator 

will notify you of approval or denial within 90 days...Neither submittal of the application or the 

Administrator’s failure to approve or disapprove the application relieves you of the responsibility 

to comply with any provision... [63.1350(o)(4&5)] 

Commenter states that if Administrator does not take action with the specified timeframe, the 

alternate method should be approved.

Response: The commenter is correct that the Administrator's failure to approve or disapprove an 

alternative monitoring application or request under 63.8(f) does not relieve a source of the 

responsibility to comply with the rule provisions. Nevertheless, if the application or request is 

for an alternative test method (which would be the case if the monitoring serves as the 

performance test method, e.g., mercury monitoring, HCl monitoring, THC monitoring, or flow 

monitoring under Subpart LLL), then the General Provisions (63.8(f)(3)) do allow the 

owner/operator to use an alternative test method in the absence of notification of 

approval/disapproval within 45 days after submission of a request. However, under 63.8(f)(4)) 

should the Administrator find reasonable grounds to dispute the results obtained by the 

alternative test method, he/she can require that the specified method be used in a retest.
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Other Issues: Comment Regarding 63.1350(o)(4&5)

Commenter (0505 - Appendix G) stated "Why only applicable to Hg? Standards on a dry basis 

should be allowed to rely on default moisture from annual RATA as is allowed under GHG 

monitoring. For Hg, both Hg and flow monitors are on a wet basis, so no moisture correction 

factor is needed to calculate mass emission rates, which are then divided by production rates to 

get to units of standard. Should not be an issue. This was asked in Dec 2010, but it was not 

addressed by the EPA." 

This comment is in reference to the following requirement: ensure appropriate corrections for 

moisture are made when measuring flow rates used to calculate mercury emissions. 

[63.1350(o)(4&5)] 

Commenter states that if moisture corrections are required, the default moisture from annual 

RATA is acceptable.

Response: The EPA does not see a need to modify the requirement for use of appropriate 

connections for moisture when measuring flow rates used to calculate mercury emissions. We 

are only pointing out that sources should be aware of their measurement parameters and report 

appropriate and consistent data. RATA tests should not involve the use of ‘default’ values, but 

rather should consist of measured values during the testing.

7.18 Other Issues: Comment Regarding 63.1350(1) and 63.1350(m)

Commenter (0505 - Appendix G) stated "The regulation at (m)(3) requires the determination 

(and presumably recording) of 3-hour block averages. Since the limit is on a 30-day RA basis, 

why are 3-hour blocks needed? This was asked in Dec 2010, but it was not addressed by the 

EPA." 

This comment is in reference to the following requirement: must comply with (m)(1) through 

(m)(4) for CMS or CPMS. [63.1350(1) and 63.1350(m)] 

Commenter recommends that EPA eliminate the requirement for 3-hr block averages. Delete 

(m)(3): Determine the 3-hour block average of all recorded readings.
153

Response: We have changed the requirement to 1 hour block averages. One hour block 

averages are necessary to calculate the average hourly emission rates that are then used to 

calculate emissions overs a 30 day period.

7.19 Other Issues: Comment Regarding 63.1340(b)(6) and 63.1345

Commenter (0505 - Appendix G) stated "Previously 63.134(c) stated: “Furthermore, the first 

conveyor transfer point subject to this subpart is the transfer point associated with the conveyor 

transferring material from the raw material storage to the raw mill”. Industry needs greater 

clarification as to where LLL starts. Further, the preamble does not address why the change was 

made to 63.1340(c). The proposed change suggests that all affected sources onsite are subject 

unless they are subject to NSPS Subpart OOO." 

This comment is in reference to the following requirement: both include raw material storage 

bins as affected sources. [63.1340(b)(6) and 63.1345] 

Commenter recommends that the EPA reconsider its decision and restore the amended regulatory 

text of 63.1340(c).

Response: We believe the amendatory language as proposed makes it clear what sources are 

subject to Subpart LLL. The reasons for the original change to the text of 63.1340(c) were 

previously discussed in both the 2006 and the 2010 rulemakings.

7.20 Other Issues: Comment Regarding 63.1340(b)

Commenter (0505 - Appendix G) stated "Commenter (0505) states that coal mill receiving kiln 

gas and having separate exhaust is not listed as an affected source." 

This comment is in reference to the following requirement: clarified affected sources 

[63.1340(b)] 

Commenter recommends that EPA change language of 63.1340(b)(1) to: Each kiln, including 

alkali bypasses and inline coal mills, except for kilns that burn hazardous waste and are subject 

to and regulated under subpart EEE of this part.
154

Response: All coal mills receiving kiln exhaust are defined as in line coal mills in rule text. 

This would include coal mills which have a separate coal mill exhaust. In addition, we have 

added the phrase, “and inline coal mills” to 1340(b)(1).

7.21 Other Issues: Comment Regarding THC and Greenfield/Brownfield Dryers

One commenter (0472) asked if the THC limits on raw material dryers apply to both greenfield 

and brownfield raw material dryers?

Response: Yes, the THC limits apply to both greenfield and brownfield raw material dryers. In 

the 2010 rule, we make no distinction between brownfield and greenfield sources.

7.22 Other Issues: Comment Regarding EPA Rationale and Authority for Startup and 

Shutdown Provisions and Revising SSM Provisions in Existing Rules

The SSM Coalition states that the EPA does not have authority to amend existing MACT 

standards to make them more stringent. The commenter asserts that the EPA’s authority under 

CAA section 112(d)(6) is to “review and revise as necessary (taking into account developments 

in practices, processes, and control technologies), emissions standards promulgated under this 

section no less often than every 8 years.” According to the commenter, the EPA did not invoke 

its section 112(d)(6) authority to support the proposed SSM provisions, but even if it had, 

section 112(d)(6) does not provide broad authority to reconsider aspects of previously issued 

MACT standards unrelated to “developments in practices, processes, and control technologies.” 

Thus, the commenter concludes, the EPA cannot simply revisit and redo a MACT determination 

long after it has been issued, as the EPA attempts to do with the proposed SSM provisions.

Response: No amendments to this rule are based on CAA section 112(d)(6)., therefore, this 

comment does not apply to this rulemaking action. [This comment was carried over by 

incorporation by reference by PCA of comments on the Ferroalloy RTR proposal].
155

Comment: The SSM Coalition states the proposed SSM provisions are not required in order to 

be consistent with Sierra Club v. EPA. The commenter states that the Sierra Club decision does 

not prevent the EPA from adopting emission standards for SSM periods that are different from 

those required during periods of normal operation. The commenter adds that the Sierra Club 

decision does not mean that the EPA is barred from using a “requirement relating to the 

operation or maintenance of a source to assure continuous emission reduction” as the emission 

standard that applies during such events. The commenter asserts that the Sierra Club decision 

only rejected the EPA’s assertion that it had discretion to decide not to impose any emission 

standard covering SSM periods. Thus, according to the commenter, despite the EPA’s 

implications to the contrary, the Sierra Club decision expressly recognized that different 

standards, including non-numerical standards, may (and in some cases must) apply during nonstandard operating conditions, such SSM.

First, the commenter explains that the Sierra Club decision interpreted the NESHAPs General 

Provisions. The commenter adds that it did not by its terms address what the EPA may or may 

not include in category-specific MACT standards. Second, the commenter states that the Sierra 

Club decision did not say that the same emission limitations that the EPA has derived for normal 

operations must also apply during SSM events. The commenter states that Sierra Club does not 

preclude the EPA from applying different standards during SSM events than apply during 

normal operations. The commenter concludes that there is ample precedent for the EPA applying 

a different standard during SSM events. 

Third, the commenter states that the Sierra Club decision did not address whether the EPA could 

use a “design, equipment, work practice or operational standard,” as authorized under CAA 

section 112(h) and included in the definition of “emission limitation” and “emission standard” in 

CAA section 302(k), in lieu of a numerical emission limitation during SSM events. The 

commenter adds that the EPA cannot hide behind the Sierra Club decision as a justification for 

ignoring an inability of even the “best performers” to achieve during SSM events the emission 

limitations the EPA has established for normal operations. Moreover, the commenter concludes 

that the approach the EPA is proposing would not establish “continuous section 112-compliant 

standards” that the Sierra Club decision concluded are required. 

Felman states that the EPA has interpreted the Sierra Club decision regarding SSM too broadly, 

that the decision focused on the manner in which the EPA had implemented the SSM exemption 

under section 112 – not the validity of the exemption itself. The commenter asserts that the 

Sierra Club decision requires the EPA to establish standards under section 112 that apply during 

all facets of a facility’s operation – whether an emission standard under section 112(d) or a workpractice standard under section 112(h), but that it did not overrule significant pre-existing case 

law controlling how these standards must be developed. Thus, the commenter reasons, because a 

MACT standard is technology-based, it must be based on what technology can achieve, with the 

only difference being how the EPA must treat the 1% of operational periods when the EPA’s 

99% UPL predicts even MACT cannot achieve the emission standards. The commenter states 

that these periods must be included within the MACT standard itself, regulated through an 
156

independent standard, such as a work practice standard where a specific emissions limit is 

impracticable, or excused through the mechanism of an affirmative defense. The commenter 

agrees with the EPA’s decision that an affirmative defense is the appropriate mechanism to 

implement the Sierra Club decision but it must remain in compliance with established case law 

regarding development of MACT standards.

Response: This comment (which was incorporated indiscriminately by reference) relates to 

issues settled in the 2010 rule and not reopened here. (The comment also fails to note that all 

issues related to startup and shutdown standards were resolved in EPA’s favor in the PCA v. 

EPA litigation (665 F. 3d at 189)). The issue of including malfunction conditions in floor 

calculations thus is not part of this proceeding and EPA is not required to address these untimely 

comments. If any response is considered necessary, the EPA does not claim that the Sierra Club

case constrains its authority to prescribe different standards for periods of start and shutdown 

(and adopted such standards in this rule) or for periods of malfunction. However, , the EPA has 

determined that CAA section 112 does not require that emissions that occur during periods of 

malfunction be factored into development of CAA section 112 standards. The EPA must 

establish emission standards that “limit the quantity, rate, or concentration of emissions of air 

pollutants on a continuous basis.” 42 U.S.C. § 7602(k)(defining “emission limitation and 

emission standard”). See generally Sierra Club v. EPA, 551 F.3d 1019, 1021 (D.C. Cir. 2008) 

(emissions limitations under CAA section 112 must both continuously apply and meet section 

112’s minimum stringency requirements, even during periods of startup, shutdown and 

malfunction). We have set the MACT standard at a level that a well-operated source should be 

able to meet during 99% of all stack tests, which we believe sufficiently accounts for normal 

operating variability. 

In the event that a facility is unable to meet the MACT standard, the EPA is finalizing the 

proposed affirmative defense to civil penalties language, with minor revisions, for violations of 

the standards that are caused by malfunctions (discussed elsewhere in this document). 

Additionally, the EPA does not agree that it is possible to gather representative data reflecting 

emissions during malfunctions, in order to consider malfunctions in its MACT floor calculations. 

The EPA asserts that data collected during an event that meets the definition of malfunction is 

only representative of that malfunction, and the EPA could not assert that the event would be 

representative of the same kind of malfunctions that might happen in the future, even at the same 

source. The EPA further disagrees that the EPA could characterize any specific malfunction 

event or events as representative for a source category.
157

Comment: The SSM Coalition states that the EPA must fully justify applying the same 

emission limitations during startup and shutdown as during normal operations. The commenter 

states that there are numerous reasons why a source might not be able to comply, during periods 

of startup or shutdown, with emission limitations established based on performance during 

steady-state operation, even if the control devices used are started up before the process units 

and are operational during the shutdown phase of a process. The commenter believes the EPA 

must conduct a thorough analysis and determine whether it is representative of the performance 

of best-performing sources (the MACT floor) to require ferroalloys plants to achieve the same 

emission limitation during startup and shutdown as during normal operations. The commenter 

states that the EPA cannot conclude that special provisions for emissions during startup and 

shutdown are not needed based on “mere speculation.” The commenter believes that the default 

assumption must be that they are needed. The EPA previously determined, in establishing the 

existing Subpart XXX standards, that the best performers on which the MACT standards were 

based may not achieve those standards during startup and shutdown. The SSM Coalition is 

skeptical that the EPA has conducted a sufficient analysis to demonstrate the achievability of 

the MACT emission limits established for normal operations during startup and shutdown 

events, because of likely limitations in the available data.

The commenter notes there are several reasons why adequate data often do not exist to allow the 

EPA to conclude that an emission limitation established for normal operations also represents the 

performance of the best demonstrated control technology during startups and shutdowns. The 

commenter adds that these factors would cause the EPA to understate emissions occurring during 

startup and shutdown.

The commenter adds that an additional problem is that it can be unclear whether a condition that 

leads to excess emissions should be characterized as a startup or shutdown event or a 

malfunction event. The commenter believes that without a clear demarcation (both in the EPA 

regulations and in practice), the EPA may be analyzing data sets that exclude events that were 

treated as malfunctions but that the EPA would say should be included in calculating average 

performance as startup or shutdown conditions.

Response: These comments are moot given that EPA is adopting work practices as the standards 

during startup and shutdown in the amended rule.
158

Comment: The SSM Coalition believes the EPA is required to take malfunctions into account 

when adopting emission standards. The commenter states that the EPA offers very little support 

for their assertion that “EPA‘s approach to malfunctions” in setting emissions standards “is 

consistent with CAA section 112 and is a reasonable interpretation of the statute.” The 

commenter states that there is nothing in CAA section 112 that allows the EPA to ignore 

malfunctions and set MACT standards based on a level of emissions that even best-performing 

sources only achieve part of the time.

The commenter believes the EPA offers a backwards, results-driven rationale for ignoring 

malfunctions, which directly contravenes congressional intent that MACT floor standards be 

based on what the best sources actually achieve: “accounting for malfunctions could lead to 

standards that are significantly less stringent than levels that are achieved by a well-performing 

non-malfunctioning source.” The commenter states that the EPA cannot ignore the requirement 

that MACT floor standards reflect performance actually achieved just because the EPA would 

like the standards to be more stringent than that actual performance reflects.

The commenter believes that by proposing MACT standards that the EPA recognizes even the 

best performing existing sources cannot achieve part of the time, the EPA is going beyond the 

MACT floor, yet without making the demonstrations that the statute and case law require the

Agency to make in order to impose beyond-the-floor MACT standards. The commenter 

disagrees that the EPA acknowledges that malfunctions are inevitable, even for the best 

performing sources, and yet refuse to include emissions data representing malfunctions in 

calculating the MACT floor, and then require that those MACT floor limitations be met even 

during malfunctions. The commenter asserts that if it is possible to gather sufficient 

representative data reflecting emissions during malfunctions, then the EPA is obligated to 

consider those data in its MACT floor calculations for steady-state operating conditions.

The SSM Coalition suggests several options the EPA could use for setting MACT standards 

under CAA section 112 that would apply during malfunction events. The commenter states that 

the EPA might be able to establish an emission limitation that applies at all times, but that has an 

averaging time of sufficient duration that short, infrequent spikes in emissions due to 

malfunctions would not cause the source to exceed the emission limitation (while at the same 

time ensuring that the source does not operate in a way that causes frequent, lengthy excursions 

above the normal controlled emission rate). As an alternative, the commenter suggests that the 

EPA also could use the flexibility accorded by CAA section 302(k) (defining “emission 

limitation” and “emission standard” to include “any requirement relating to the operation or 

maintenance of a source to ensure continuous emission reduction, and any design, equipment, 

work practice or operational standard promulgated under” the CAA) to address emissions during 

malfunction events through operational requirements rather than by applying the same limits on 

pollutant concentrations in exhaust gases that apply during normal operations. The commenter 

adds that the EPA could have concluded that it has grounds to exercise its authority under CAA 

section 112(h) to promulgate a design, equipment, work practice, or operational standard, or 

combination thereof, because it is not feasible to prescribe or enforce an emission standard.
159

The SSM Coalition states that the proposed affirmative defense is not a substitute for addressing 

malfunction events in the emission standards themselves. The commenter asserts that the 

Proposed Standards, incorporating the affirmative defense, still do not represent emission 

limitations “achieved” by best-performing existing sources under CAA section 112(d)(3), nor do 

they meet the criteria for establishing beyond-the-floor emission standards under CAA section 

112(d)(2).

Response: See previous response. Moreover, as explained in earlier comment responses, we are 

including an affirmative defense in the final rule as we have in other recent section 112 rules so 

as to balance the tension, inherent in many types of air regulation, to ensure adequate compliance 

while simultaneously recognizing that despite the most diligent of efforts, emission limits may be 

exceeded under circumstances beyond the control of the source. Mont. Sulphur & Chem. Co. v.

EPA, 2012 U.S. App. LEXIS 1056 (Jan 19, 2012) (rejecting argument that reliance on the 

affirmative defense was not adequate). The EPA must establish emission standards that “limit the 

quantity, rate, or concentration of emissions of air pollutants on a continuous basis.” 42 U.S.C. § 

7602(k) (defining “emission limitation and emission standard”). See generally Sierra Club v. 

EPA, 551 F.3d 1019, 1021 (D.C. Cir. 2008) (emissions limitations under CAA section 112 must 

both continuously apply and meet section 112’s minimum stringency requirements, even during 

periods of startup, shutdown and malfunction). Thus, we are required to ensure that section 112 

emissions limitations are continuous.

Comment: The SSM Coalition requests that malfunction reporting be required on a semiannual basis, for malfunctions that occurred during the preceding 6 months, which is the same 

frequency as similar reports pursuant to NESHAPs and Title V requirements. The commenter 

states that this change would enable the EPA to review the source’s compliance history and the 

measures being taken to address malfunctions, without imposing unworkable reporting 

deadlines, or potentially encouraging sources to bombard the Agency with reports for 

malfunctions that may not ultimately result in the source exceeding the 30-day average emission 

limitation. The commenter adds that the EPA has not justified departing from its conclusion, 

reflected in the current subpart XXX standards, that semi-annual reporting of malfunctions is 

sufficient.

The SSM Coalition states that the requirement in proposed §63.1627(b) to notify the 

Administrator by telephone or fax as soon as possible, but no later than two business days after 

the malfunction begins, and then to submit a written report within 45 days of the initial 

occurrence of the malfunction that demonstrates, “with all necessary supporting documentation,” 

that the source met all of the multitude of criteria for the affirmative defense, is unreasonable and 

unnecessary. The commenter believes it is extremely inefficient and burdensome, for both 

sources and regulators, to require a complete justification of the affirmative defense before the 

enforcement authority has indicated any need for further investigation.
160

Response: The rule’s affirmative defense provisions in §63.1627 (and §63.1662) have been 

revised, in the final rule, to remove the 2-day notification requirement. In addition, we have 

revised the final rule to allow an owner or operator of the affected source seeking to assert an 

affirmative defense for violations of an emission standard during a malfunction to submit a 

written report to the Administrator in the first periodic compliance, deviation report or excess 

emission report otherwise required after the initial occurrence of the violation of the relevant 

standard (which may be the end of any applicable averaging period). If such compliance, 

deviation report or excess emission report is due less than 45 days after the initial occurrence of 

the violation, the affirmative defense report may be included in the second compliance, deviation 

report or excess emission report due after the initial occurrence of the violation of the relevant 

standard.

The EPA inadvertently omitted specific references to changes made to §63.1656(a)(6) in the 

proposal preamble. However, as noted, we did discuss the comparable changes made to 

§1625(a)(5). 
161

Section 8: Comments Regarding General Support and Opposition 

to the Proposed Rule

8.1 General Support for Proposed Standards

One commenter (0519) stated that they are generally supportive of many modifications which 

EPA has proposed in the reconsideration, but have implementation and operational concerns 

with some areas of the proposed rule modifications being proposed. Overall, the commenter 

feels that the proposed rule, with certain modifications to address the practical concerns we have 

identified, will accomplish the goal of reducing the emissions of hazardous air pollutants from 

cement kilns throughout the United States while preserving critical jobs at our facilities and 

others across the U.S.

Commenter (0512) is pleased the EPA adopted regulations on September 9, 2010 for new and 

existing portland cement kilns and believe that they were necessary to protect public health.

Response: EPA has noted the commenters’ support for this rule.

8.2 General Support for Many of the Proposed Standards with Some Specific 

Concerns

One commenter (0525) fully supports the position taken by PCA. Specifically, they support 

issues related to clarifying certain definitions, clarifying the basis for determination of certain 

emission standards for PM and other constituents, amending or clarifying testing and 

monitoring protocols, and Start up and shutdown requirements.

One commenter (0525) fully supports the position taken by PCA. Specifically, they support 

issues related to clarifying certain definitions, clarifying the basis for determination of certain 

emission standards for PM and other constituents, amending or clarifying testing and 

monitoring protocols, and Start up and shutdown requirements.

 Commenter (0476) incorporated by reference the comments submitted by the Portland Cement 

Association (PCA) (docket ids: EPA-HQ-OAR-2011-0817-0505, EPA-HQ-OAR-2011-0817-
162

0483).

Commenter (0507) incorporated by reference comments from the Portland Cement Association 

(PCA) (docket id: EPA-HQ-OAR-2011-0817-0505).

Commenter (0523) stated support for the most part of comments from the Portland Cement 

Association (PCA) (docket id: EPA-HQ-OAR-2011-0817-0505).

One commenter (0483) stated that they concur with the PCA’s analysis assessing the time 

necessary for a typical plant to prepare for compliance and agree with the conclusion that this 

process will take at least two years to complete for most plants. Consequently, we endorse the 

EPA proposed reset of the compliance deadline from September 2013 to September 2015.

Commenter 0519 supports PCA’s comments regarding industry’s concerns about definitions 

which EPA proposes or has failed to propose. 

Response: EPA has noted the opposition to this rule.

8.3 General Opposition to Weakening of Standards

Commenter (0512) is disappointed in the EPA’s failure to fully consider multi-pollutant sector 

based approach by overlooking the emissions of nitrogen oxides (NOx) from portland cement 

plants constructed, reconstructed, or modified on or before June 6, 2008. The commenter urges 

EPA to take action to mitigate NOx emissions from the portland cement plants that were 

constructed, reconstructed, or modified on or before June 6, 2008.

Response: This comment relates to issues not posed by the reconsideration proposal, and 

therefore requires no response. 

8.4 General Opposition – Mass Email Campaigns

We received over 22,000 comments as part of mass email campaigns that opposed weakening 

of standards and extending the compliance period.
163

Response: See preamble section V.