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# National Emission Standards for Hazardous Air Pollutants for Brick and S t ructural Clay Products Manufacturing Background Information for Final Rule

Summary of Public Comments and Responses

September 2015ii This page intentionally left blank.iii National Emission Standards for Hazardous Air Pollutants

for Brick and Structural Clay Products Manufacturing Background Information for Final Rule

Summary of Public Comments and Responses

Contract No. EP

- D

- 11

- 084 Work Assignment No. 3

- 12

U.S. Environmental Protection Agency Office of Air Quality Planning and Standards Sector Policies and Programs Division Research Triangle Park, North Carolina 27711

September 2015iv Disclaimer

This report has been reviewed by the Sector Policies and Programs Division of the Office of Air Quality Planning and Standards, EPA, and approved for publication. Mention of trade names or commercial products is not intended to constitute endorsem ent or recommendation for use.v TABLE OF CONTENTS

LIST OF ACRONYMS AND UNITS OF MEASURE

................................ ................................ vii
1.0 Introduction

................................ ................................ ................................ ............................... 1 2.0 Legal

................................ ................................ ................................ ................................ ......... 4 3.0 Applicability

................................ ................................ ................................ ............................. 6 3.1 Source Category/NAICS Codes

................................ ................................ ............................ 6 3.2 Affected Sources

................................ ................................ ................................ ................... 6 3.3 Major/Area Sources

................................ ................................ ................................ .............. 7
4.0 Su bcategories

................................ ................................ ................................ ............................ 9
5.0 Test Data

................................ ................................ ................................ ................................ . 15 6.0 Type of Standard

................................ ................................ ................................ ..................... 18
7.0 MACT Floors

................................ ................................ ................................ .......................... 30 7.1 Determining Sources in Floor Pool

................................ ................................ .................... 30
7.2 UPL

................................ ................................ ................................ ................................ ..... 31
7.3 Emission Limit

................................ ................................ ................................ .................... 43 7.3.1 Manipulation of Data for MACT Floor

................................ ................................ ....... 43 7.3.2 Equivalent Limits

................................ ................................ ................................ ......... 49
7.3.3 3xRDL

................................ ................................ ................................ .......................... 50 7.3.4 Floor Calculations for Alternate Approaches

................................ .............................. 51 7.4 Achievability of Standards

................................ ................................ ................................ .. 53
8.0 Health

- Based Standards

................................ ................................ ................................ .......... 55
8.1 Health Thresholds

................................ ................................ ................................ ............... 55 8.2 Discretionary Authority

................................ ................................ ................................ ...... 55 8.3 Setting Level of Standard

................................ ................................ ................................ ... 55 8.3.1 Ample Margin of Safety

................................ ................................ .............................. 55
8.3.2 Risk Assessment

................................ ................................ ................................ .......... 55
8.3.3 Level of Standard

................................ ................................ ................................ ......... 56
8.3.4 Other

................................ ................................ ................................ ............................ 58 8.4 General Support

................................ ................................ ................................ .................. 59
9.0 Work Practice Standards

................................ ................................ ................................ ......... 61 10.0 Startup and Shutdown

................................ ................................ ................................ ........... 64
11.0 Malfunction

................................ ................................ ................................ ........................... 76 12.0 Testing and Initial Compliance Requirements

................................ ................................ ...... 82 13.0 Continuous Compliance Requirements

................................ ................................ ................. 84 14.0 Alternate Approaches

................................ ................................ ................................ ............ 86 15.0 Costs and Impacts

................................ ................................ ................................ ................. 88
15.1 Costs and Emissions Reductions

................................ ................................ ...................... 88vi 15.2 Economic Impacts

................................ ................................ ................................ ........... 102
16.0 S tatutory and Executive Order reviews

................................ ................................ .............. 105
16.1 Executive Orders 12866 and 13563

................................ ................................ ................ 105 16.2 Paperwork Reduction Act

................................ ................................ ............................... 106 16.3 Regulatory Flexibility Act

................................ ................................ .............................. 112
17.0 General Comments

................................ ................................ ................................ .............. 115 17.1 General Opposition

................................ ................................ ................................ ......... 115 17.2 Incorporation by Reference

................................ ................................ ............................ 115
18.0 Other Comments

................................ ................................ ................................ ................. 116vii LIST OF ACRONYMS AND UNITS OF MEASURE

$ dollars
μg microgram acfm actual cubic feet per minute ACI activated carbon injection ADL above detection limit APCD air pollution control device Ass ’ n association ASTM American Society for Testing and Materials ATSDR Agency for Toxic Substance s and Disease Registry BDL below detection limit BIA Brick Industry Association BSCP brick and structural clay products CAA Clean Air Act CBC Continental Brick Co. CEDRI Compliance and Emissions Data Reporting Interface CFR Code of Federal Regulations Cir. Circuit Court Cl 2 chlori n e CO 2 carbon dioxide CWA Clean Water Act D.C. District of Columbia D/F dioxins/furans DIFF dry injection fabric filter DLA dry limestone adsorber DLL detection level limited DLS/FF dry lime scrubber and fabric filter dscf dry standard cubic foot dscm dry standard cubic meter
e.g. exempli gratia (for example) EGU electric generating unit EO Executive Order EPA U.S. Environmental Protection Agency ERT electronic reporting tool ESP electrostatic precipitator F Fahrenheit FB field blank FF fabric filter FR Federal Register ft 3 cubic foot FTIR Fourier transform infrared
gr grain HAP hazardous air pollutants HBEL health

- based emission limitviii HCl h ydrogen chloride HCN hydrogen cyanide HEM

- 3 Human Exposure Model

, Version 3 HF h ydrogen fl uoride Hg mercury HI hazard index hr hour i.e. id est (that is) ICR information collection request id. idem (the same) IRIS Integrated Risk Information System KMnO 4 p otassium permanganate kWh kilowatt

- hour lb pound MACT maximum achievable control technology MACT TF MACT Task Force MDL method detection level MMBtu million British thermal units NACAA National Association of Clean Air Agencies NACWA National Association of Clean Water Agencies NAICS North American Industry Classification System NBC Na sh Brick Co. NESHAP national emission standards for hazardous air pollutants NOx nitrogen oxides NRDC Natural Resources Defense Council NSPS new source performance standard O&M operation and maintenance O 2 oxygen OM&M Operations, Maintenance and Monitoring OMB Office of Management and Budget PIC product of incomplete combustion PM particulate matter ppb parts per billion
ppm parts per million PS performance specification PTE potential to emit PTFE polytetrafluoroethylene QA quality assurance QA/QC quality assurance/quality control R2C Residual Risk Coalition RDL representative detection level RIA Regulatory Impact Analysis RTR Risk and Technology Review SAB Science Advisory Board SBA Small Business Administration SBREFA Small Business Regulatory Enforcement Fairness Actix SD/ESP spray dryer with ESP SO 2 sulfur dioxide SOx sulfur oxides SSM startup, shutdown and malfunction TOSHI target organ

- specific hazard index tpy tons per year UPL u pper prediction limit

v. versus VE visible emissions1 1.0 Introduction

Section 112(d) of the Clean Air Act (CAA) requires the U.S. Environmental Protection Agency (EPA) to set emissions standards for hazardous air pollutants (HAP) emitted by major stationary sources based on the performance of the maximum achievable control t echnology (MACT). The EPA issued the national emission standards for hazardous air pollutants ( NESHAP ) for Brick and Structural Clay Products (BSCP) Manufa cturing on May 16, 2003. The NESHAP w as subsequently challenged, and the U.S. Court of Appeals for th e D.C. Circuit vacated and remanded the standards on March 13, 2007. To address the vacatur and remand of the original NESHAP, new standards were p roposed and published in the Federal Register on December 18, 2014. The proposed standards regulate emissions of acid gases, hazardous metals, and dioxins/furans from affected sources in the BSCP ca tegory

.

An initial 60

- day period ending February 17, 2015 was provided for the public to submit comments to the EPA on the proposal. The public comment period was subsequently extended to 90 days, ending March 19, 2015. The following sections of this document summarize the public comments received on the proposal and present EPA ’ s responses to those comments. A total of 52 public comments were received on the propos ed BSCP NESHAP. See www.regulations.gov

, D ocket ID No. EPA

- HQ

- OAR

- 2013

- 0291 for the comp lete public comments on the BSCP NESHAP. Table 1 below list s the document numbers assigned to the public comments, the

names of the commenters, and their titles and affiliations. For simplicity, only the last four digits of the document numbers specific to each commenter are presented in this document (e.g., 0 543

, instead of EPA

- HQ

- OAR

- 2013

- 029 1

- 0 543 ).2 Table 1. List of Comment ers on Proposed NESHAP for BSCP Manufacturing

Document I tem No.

(EPA

- HQ

- OAR

2013

- 0291

- ) Commenter/ Title /Affiliation
0513 R on Stroh , W.L. Tucker Supply Co., Inc.
0514 Employees of Whitacre Greer Co.
0515 Em ployees of Glen

- Gery Corp.
0516 Dr. Garth Tayler, Techni cal Director, Acme Brick Co.
0517 Claudia R. Rodgers, Acting Chief Counsel

, and David Rostker

, Assistant Chief Counsel, Small Business Administration (SBA) Office of Advocacy
0518 Janet Whitacr e Kaboth, Whitacre Greer Co.
0519 G. Vinson Hellwig, Michigan

, and Robert H. Colby, Chattanooga, Tennessee, Co

- Chairs, National Association of Clean Air Agencies (NACAA)
0520 Carol Conley, Vice President, Human Resources and Environmental Affairs, Cherokee Brick & Tile Co.
0521 Ryan L. Parker, President and CEO, Endicott Clay Products Co.
0522 John E. Miller, Engineering, Environmental, Health and Safety Manager, Whitacre Greer Co.
0523 Creighton H. McAvoy, Presi d ent, The McAvoy Vitrified Brick Co.
0524 Glenn L. Unterberger and Ronal d M. Varnum, Ballard Spahr LLP
0525 Michael H. Winek, Attorney at Law, Babst Calland
0526 Anonymous
0527 Donald B. Sult, Vice President, Continental Brick Co

. (CBC)
0528 Allen Puckett III, President, Columbus Brick Co

. 0529 Michael B. Foster, Chairman of the Board an d CEO, Statesville Brick Co.
0530 Ray Leonhard, President and CEO, Brick Industry Association (BIA)
0531 Davis Henry, President, Henry Brick Co

. , Inc.
0532 Suzanne McAnaller, President, Donley Brick Co.
0533 SSM Coalitio n et al.
0534 Keith Depew, President, Cladding Operations, and Mary Ann Keon, Environmental Director, Boral Industries Inc.
0535 Gary S. Davis, V.P. of Sales , Endicott Clay Products Co.
0536 Matthew R. Welte, Chief Operating Officer, Summit Brick & Tile Co

. 0537 Keith Depew, President, Cladding Operations, and Mary Ann Keon, Environmental Director, Boral Industries Inc.
0538 E. J. Biernesser, Skyline Brick
0539 Michael Hartman, Air

- T ech Environmental, LLC
0540 B.T. Schimmel , Consultant, Boral Bricks, Inc., and Irene Kuo, RTP Environmental Associates, Inc., on behalf of the Brick Industry Association (BIA) MACT Task Force3 Document I tem No.

(EPA

- HQ

- OAR

2013

- 0291

- ) Commenter/ Title /Affiliation
0541 Michael Hartman, Principal Scientist, Air

- T ech Environmental, LLC
0542 Paul G. Regina, Regulatory Specialist, Brick Industry Association (BIA)
0543 Susan J. Miller, Vice President, EH&S, Brick Industry Association (BIA)

, on behalf of the Brick Industry Association (BIA) MACT Task Force
0544 Paul G. Regina, Regulatory Specialist, Brick Industry Association (BIA)
0545 Mike Rixner, Technical Manager, Brampton Brick, Inc.
0546 Anonymous
0547 William L. Wehrum, Counsel, Hunton & Williams LLP

, on behalf of the Brick Industry Association (BIA)
0548 J. R. Holton, Secretary, Lee Brick and Tile Co

. 0549 Matthew Todd, Chairman, Residual Risk Coalition (R2C)
0550 Bill Spakes, Plant Manager, Hanson Brick Elgin Facility
0551 Jason Smith, Plant Manager, Hanson Brick Monroe Facility
0552 Bob Studer, Area Operations Manager, Hanson Brick Mineral Wells Ea st and West Plants
0553 Steve Matsick, President, Glen

- Gery Corp

. 0554 Nicholas Morales, Earthjustice, on behalf of Natural Resources Defense Council & Sierra Club
0555 Warren Paschal, Manager of Environmental Compliance, General Shale Brick, Inc.
0556 Charles Smith, President and CEO , General Shale Brick, Inc.
0557 Martin Brown, Plant Manager, Hanson Brick Roseboro Facility
0558 Robert F. Belden, President and CEO

, and Bradley H. Belden, Director, Support Services, The Belden Brick Co

. 0559 Jeff A. Wyers, Plant Manager, Nash Brick Co. (NBC)
0560 Mass comment campaign, sponsoring organization unknown
0561 Mass comment campaign, sponsoring organization unknown
0562 Robert Clements, Plant Manager, Hanson Brick Michigan Plant, Corunna, Michigan
0563 W. Fletcher Steele, President, Pine Hall Brick Co., Inc.
0564 1 Harry Holder, Acme Brick Co.
Endicott 1 Ryan L. Parker, President and CEO, Endicott Clay Products Co.

1 Late comment4 2.0 Legal

Comment 1: Commenter 0554 stated that the EPA ’ s failure to set a standard for hydrogen cyanide (HCN) for Brick and Clay Ceramics violates CAA section 1 12. The commenter noted that the CAA mandates that EPA “ shall require the maximum degree of reduction in emissions of the hazardous air pollutants subj ect to [section 112 ]. ” Therefore, the EPA is required to limit all hazardous air pollutants emitted from the source categories. CAA s ection 1 12(d)(2)

- (3); Nat ’ l Lime Ass ’ n v. EPA , 233 F.3d 625 (D.C. Cir. 2000). It is unlawful for EPA to no t set a limit for a

s ection 1 12

- listed pollutant. Nat ’ l Lime Ass ’ n , 233 F.3d at 634.

The commenter noted that HCN is listed as a hazardous air pollutant. HCN exposure at high levels swiftly harms the brain and heart, beginning with rapid breathing, followed by convulsions, and loss of consciousness, and can even cause coma and death. More commonly, even low

- level exposure to HCN is associated with breathing difficulties, chest pain, vomiting, headaches, and enlargement of the thyroid gland (see Agency for Toxic Substances a nd Disease Registry ( ATSDR ) , ToxFaqs for Cyanide (July 2006)).

The commenter noted that electric generating units burning coal emit HCN and stated that it is also likely, then, that brick and clay ceramics units burning coal emit HCN. The EPA requested th at brick and clay ceramics facilities test for hydrogen chloride ( HCl )

, hydrogen fluoride ( HF )

, and chlorine (Cl 2 ) emissions but did not request they test for HCN emissions. T he commenter stated, the EPA ’ s failure to require testing cannot excuse the EPA f rom its legal obligation to regulate all emitted hazardous air pollutants. The commenter asserted that to fulfill its duty under the CAA, the EPA must set CAA section 1 12(d) standards for HCN.

Response 1: The EPA disagrees with the commenter that HCN standards must be set for coal

fired BSCP tunnel kilns. In the BSCP manufacturing inventory, there are 18 active BSCP tunnel kilns out of 220 kilns nationwide using coal as the primary fuel, located in Georgia, Indiana, Kentucky, North Carolina, South Caro lina, Tennessee, Virginia , and West Virginia

. The commenter argued that because electric generating units ( EGUs ) burning coal emit HCN, it is also likely that BSCP tunnel kilns burning coal also emit HCN and, therefore, the EPA must set HCN standards under section 112(d) for BSCP tunnel kilns.

To evaluate the quantity of HCN emitted from coal

- fired EGUs, we reviewed the available HCN data for EGUs fired with bituminous and subbituminous coal

. 1 We reviewed the run

- by

- run HCN emissions data; evaluated the cou nts of emissions runs labeled as above detection limit ( ADL )

, below detection limit ( BDL )

, and detection level limited ( DLL ) ; and calculated the percentage for each label. We found that 72 percent of test runs were BDL for all coal

- fired EGUs, and that 56 percent of the ADL test runs, for which there were emissions (lb/MMBtu) and heat i nput ( MM Btu/hr) data provided, were less than 1 lb HCN/hr; establish ing that there is not a significant quantity of HCN being emitted from coal

- fired EGUs. We also found that coal

- fired EGUs had an average heat input of 200 times the average for BSCP tunnel kiln s firing coal

. In addition, the highest EGU coal fired HCN lb/MMBtu run value multiplied by the highest BSCP

1 Spreadsheet Submissions from the Part III database, http://www.epa.gov/airtoxics/utility/utilitypg.html5 coal fired kiln heat input rate results in an insignif icant 0.2 lb HCN/hr value. Consequently , the EPA conclude s that: (1) HCN is even less likely to be emitted in measurable quantities from coal

- fired BSCP tunnel kilns

, (2) we were correct in not requiring the BSCP facilities test for HCN in the 2010 survey, and (3) there is no reason to require BSCP facilities to test for HCN in the future.6 3.0 Applicability
3.1 Source Category/NAICS Codes

Comment 1: Commenters 0524, 0525 , and 0543 recommended the EPA clarify the rule applicability. Commenter 0524 mentioned that a change in the North American Industry Classification System ( NAICS ) codes between 2003 ( when EPA promulgated the original NESHAP for BSCP manufacturing facilities ) and date of this current proposal raises a potential ambigui ty as to whether EPA is intending to regulate other facilities that were not subject to the original NESHAP and that are not part of the BSCP products manufacturing industry. To avoid any confusion, the commenter suggested th e EPA clarify the scope of the proposed rule to conform to the scope of the 2003 NESHAP.

Commenter 0525 and 0543 stated that there are at least two other MACT standards that have the potential to overlap brick and structural clay operations, including the Refractories MACT and the Ceram ic Tile MACT. The commenter noted that CAA section 112 plainly requires that only one categorical MACT standard apply to a given emission source. The commenter suggested that each rule should clearly delineate which emissions unit s are subject to the BSCP NESHAP and clarify that these emissions units are not simultaneously subject to another standard. Commenter 0525 requested EPA revise the applicability text and the definition of BSCP manufacturing facility in subpart JJJJJ

. Response 1: The EPA agree s wit h the commenters that additional clarity is needed concerning the applicability of subpart JJJJJ to BSCP manufacturing facilities and the applicability of subpart KKKKK to clay ceramics manufacturing facilities . Consequently

, for subpart JJJJJ, we have rev ised the applicability text in 40 CFR 63.8385(a) and the definition of BSCP manufacturing facility in 40 CFR 63.8515 to specifically exclude refractories manufacturing and clay ceramics manufacturing. Similarly, for subpart KKKKK, we have revised the applicability text in 40 CFR 63.8535(a) and the definition of clay ceramics manufacturing facility in 40 CFR 63.8665 to specifically exclude refractories manufacturing and BSCP manufacturing. We have also added a footnote to preamble Table 3 (NESHAP and In dustrial Source Categories Affected by this Action) , which lists the affected NAICS codes, clarify ing that refractories manufacturing is not included in the source categories affected by the final rule.

3.2 Affected Sources

Comment 1: Commenter 0525 reque sted the EPA revise proposed 40 CFR 63.8390(c) by add ing the underlined text:

(c) Process units not subject to the requirements of this subpart are listed in paragraphs (c)(1) through (3) (4) of this section.

(1) Kilns that are used exclusively for setting glazes on previously fired products are not subject to the requirements of this subpart. (2) Raw material processing and handling. (3) Dryers. (4) Sources covered by subpart SSSSS of this part.7 Response 1: The EPA agree s with the commenter that additional clarity is needed concerning the applicability of subpart JJJJJ (BSCP Manufacturing NESHAP) . Consequently , we have revised 40 CFR 63.8390(c) as requested to exclude sources covered by subpart SSSSS (i.e., refractory sources) . We have also revised 40 CFR 63 .8540(c) of subpart KKKKK (Clay Ceramics Manufacturing NESHAP) similarly.

Comment 2: Commenter 0543 noted the EPA defined small and large kilns based on the kiln ’ s

“ design capacity. ” The commenter stated that the “ design capacity ” of some kilns can vary based on the void space in the brick, the push rate for the kiln, and even the stacking pattern. The commenter suggested the EPA clarify that the “ design capacity ” for a kiln is the level that is f

ederally

- enforceable and listed in their Title V operating permit and typically expressed in units of tons of fired brick throughput per hour or per year. The commenter suggested that annual capacity should be converted to an hourly throughput for purposes of determining large or small by d ividing annual throughput by 8,760 hours per year.
Response 2: The EPA disagree s with the commenter that the definition for “ tunnel kiln design capacity ” should be revised to refer to the level that is federally

- enforceable and listed in the Title V operating permit. The large and small tunnel kiln subcategories were established based on the premise that there are distinct design differences between large and small tunnel kilns. Allowing a large tunnel kiln to be changed to a small tunnel kiln based on federally enforceable conditions provided in a Title V permit (such as limiting brick throughput) would be inappropriate because of the design difference bet ween large and small tunnel kilns. However, we agree with the commenter that other factors such as void space can influence the design capacity, and we have added language to the definition for “ tunnel kiln design capacity ” to account for th e se factors.

3. 3 Major/Area Sources

Comment 1: Commenter 0559 stated that as the proposed MACT will not apply to existing sources that are a true area source, or companies that do not grow or suffer major equipment damage that would require major repairs. The commenter n oted that all area sources are affected by the new source MACT, which means that they and other small businesses (area sources) would be unable to expand or rebuild due to the prohibitive costs of controls.
Response 1: Regarding the commenter ’ s concerns, t he EPA has taken significant steps to minimize the impacts of the rule on small entities while still achieving the objectives of the rule. In particular, EPA has developed the rule to accept recommendations from the Small Business Advocacy Review Panel t o the extent possible, including work practice standards for dioxins/furans and for periods of startup and shutdown

, a health

- based standard for acid gases, and kiln size subcategories

. Post

- proposal, EPA has taken additional steps to minimize the impacts of the rule on small entities, including developing raw material variability factors for
mercury (Hg) emission limits based on raw material data received during the comment period, and reevaluating stack test data used in developing the MACT floor particul ate matter ( PM ) emission limits

. Comment 2 : Commenter s 0531 , 0537, and 0543 were concerned the “once in

, always in ” provisions may prevent their plants from becoming synthetic minor sources

. Commenter 0531 noted that the EPA assumes sources can become s ynthetic m inor sources rather than complying8 with the BSCP NESHAP. However, t he commenter stated that when they contacted their state regulatory authority about the possibility of becoming a s ynthetic m inor source , they were told that since they fell under the 2003 rule they would always be subject to MACT. Therefore, the commenter asserted that they do not have the option of becoming a s ynthetic m inor source to avoid the proposed rule.

Commenter 0537 noted that another company ’ s application to become a syn thetic minor source was denied based on the “ once in

- always in rule ” for major sources.

Commenter 0543 asserted that the “ once in, always in ” policy is unlawful because the statutory definition of “ major source ” unambiguously specifies that a facility is a major source only if its potential to emit ( PTE ) exceeds the specified thresholds. If a facility is a major source and then reduces its PTE to below the HAP major source thresholds, then that facility ceases to be a major source and may no longer be subje ct to MACT standards for major sources.

Regardless of that assertion, Commenter 0543 noted o ne reason for th e confusion regarding the when the “once in, always

- in” provisions apply could be that 40 CFR part 63, subpart JJJJJ remains in the Code of Federal Regulations even though the rule was vacated almost 8 years ago. For those who could benefit from becoming a synthetic minor source, the commenter requested that EPA clarify that the “ once in, always in ” policy would not apply in this case since the 2003 B rick MACT was vacated by the courts.

Response 2 : Regarding the commenters ’ concerns, t he 2003 MACT rule was vacated in 2007 (see Sierra Club v. EPA , 479 F.3d 875 (D.C. Cir. 2007)) and the effect of that vacatur was to restore the status quo before the 2003 rule took effect. See Sierra Club v. EPA , 850 F.Supp. 2d 300, 303

- 304 (D.D.C. 2012). Thus, the “ once in/always in ” policy does not apply based on the vacated 2003 rule.9 4.0 Subcategories

Comment 1: Commenter 0522 stated that the previous vacated BS CP MACT included a subcategory for small kilns, and argued that subcategorization of kilns by size should be included in this rulemaking. The commenter stated that, beyond the obvious economic factors, the installation of an air pollution control device ( A PCD ) would have significant impact upon the products and, therefore, on the ability to successfully maintain the niche markets. As was acknowledged in the vacated MACT, brick color is an important factor in the consumer ’ s decision to buy one brick over ano ther and it is critical that color duplication be achieved on a regular basis. The commenter also noted that color is a key factor in the success of their niche paver product line. Color is affected by changes in airflow, which is greatly affected by APCD, certainly more so on a small tunnel kiln due to the slower production rates. According to the commenter, addition of an APCD would affect the historic color reproduction, possibly making duplication impossible.

The commenter stated that adding an APCD on an older small kiln would also be impractical, since the older kilns are not designed to be airtight, and the exit end has no door and the entrance to the kiln has a loosely fit non insulated sliding door. Sealing the kiln would cause changes in air pressu re distribution, moving the balance points, which in turn could cause the mixing of the waste heat and the products of combustion. The commenter asserted that this would affect the color and quality of the pavers. In order for a manufacturer of pavers to a ccount for years of wear, it is important that the color is consistent throughout the paver. Operating too lean or too rich of a mixture will result in a different firing curve, resulting in a different looking product and possibly weak inferior products.

Commenter 0522 noted several other specific differences between their small kilns and typical large kilns:

• The commenter ’ s small kilns are fired with high velocity side burners positioned at the bottom of the deck. Even with the high velocity burners, the temperature difference from top to bottom is as much as 100 degrees. Larger kilns are top

- fired with a more even temperature distribution.

• The commenter ’ s kiln cars are narrow (6 ’ wide) but higher (5 ’ in the larger kiln, a bit lower in the smaller kiln) wi th a large gap in the middle and loosely hacked to enhance airflow. A modern larger kiln is low and wide; typically 1

- 2 feet high and as much as 20 ’ wide, more densely hacked and require less airflow to achieve even heat distribution.

• The commenter ’ s kiln is not sealed, with the exit end completely open and a very loose fitting door on the entrance. Larger kilns are sealed with a vestibule. The airflow and temperature remain constant while the smaller kiln temperatures and airflow changes when the entrance is opened and shut to admit a car.

• The walls and ceilings of older smaller kilns are constructed with sizeable amounts of refractory bricks in the walls and arched ceilings. The arched ceilings allow for open spaces and airflow above the cars, something no t found in large kilns. Large kilns are typically designed with a fiber lined tight ceiling.

Response 1: The EPA agree s with the commenters that there are substantial differences based on size and type that warrant subcategorization. We will be retaining t he small and large tunnel kiln10 size subcategories for the final rule for emissions of Hg

. For the final rule, we are also exercising our discretion to subcategorize by kiln size for the PM and non

- Hg metals limits.

Concerning the issue that the installation of an APCD would have significant impact upon the products (and color variations due to airflow) , and, therefore, on the ability to successfully maintain the niche markets , the EPA did not receive data that would help to set a subcategory based on color or other categories for niche bricks, and thus cannot set a standard based on these types of products

.

C omment 2: C ommenters 0529, 0534

, 0543 , and 0559 recommended the EPA consider a subcategory for sawdust

- fired kilns venting to a sawdust dryer. Commenters 0529 and 0543 noted that sawdust dryer s were treated as a separate emissions source type under the previous BSCP NESHAP because e missions were recognized to be different based on AP

- 42 testing

. These commenters noted the previous rule required no additional numeric emission limits and exempted these units from control requirements . The commenters asserted that these sources may warrant separate treatment because there are no demonstrated controls for this source category. Commenters 0529 and 0543 stated that a sawdust

- fired kiln with a sawdust dryer represents a distinctly different operating scenario from other brick manufacturing operations.

Two c ommenter s ( 0529 and 0543) are considering conducting stack test s of their sawdust dryer exhaust.

Commenter 0534 stated that the proposed BSCP NESHAP would require that the exhaust from dryers meet the same emission requirements as exhaust from the kiln. The commenter stated their sawdust

- fired kiln would be classified as a large kiln, and the exhaust stream from the dryers cannot achieve the rule emissions limits. Adding control s to the dryer is complicated by the required temperatures and treating outlet air is limited due to the saturated airstream

. Furthermore

, the u nits intermittent operation complicate s what types of control s can be used . The commenter asserted that control options for their dryer appear to be limited, costly and would achieve minimal environmental benefits. Retrofitting the kiln and tunnel kiln to 100 percent natural gas would be expensive and would defeat the benefit of using a renewable fuel source.

Commenter 0559 questioned whether MACT is a technology forcing program or a readily available proven and sound technology regulation. The commenter r equested the EPA reinstate the appropriate subcategory for sawdust dryers that was included in the vacated 2003 BSCP NESHAP.

Response 2: The EPA does not agree with the commenters ’ request for a subcategory for sawdust

- fired kilns venting to a sawdust drye r

. Commenter 0529 stated that they are currently evaluating the potential to conduct a stack test of both their kiln and sawdust dryer exhaust. Commenter 0543 stated that

, to date, the company has been unable to finalize these plans but hopes to have the t est conducted in the near future. Commenter 0543 further stated that this company is one of only two that currently operate in this potential subcategory and is the only small business. The commenters stated they will keep EPA informed of the progress of t he testing and provide the data to EPA to support the consideration of a subcategory, if warranted.11 Until data becomes available to support subcategorization , we cannot establish a separate subcategory for sawdust

- fired kilns

.

Comment 3: Commenters 0522, 0543, and 0551 requested that the EPA consider a subcategory for kilns with low stack temperatures. Commenter 0543 stated that there are numerous uncontrolled kilns in the Brick industry that never attain the necessary stack temperature t o effectively vent their exhaust to the control devices currently identified by the EPA and used as the basis for all MACT burden calculations. These include kilns that never reach 300 degrees F and those kilns that do not maintain their stack temperatures above 300 degrees F. Commenters 0522, 0543, and 0551 noted that venting the exhaust from these kilns through a dry injection fabric filter ( DIFF ) or a dry limestone adsorber ( DLA ) would not be possible because the stack temperature will not remain above t he dewpoint for HF and HCl. Commenter 0543 noted that the EPA recognized the limitation of venting gas below the dewpoint when they established the proposed work practices for this proposed rule. Venting gas below the dewpoint would quickly and perhaps per manently render the controls useless. Commenter 0543 stated that, since the controllability of these kilns is inherently different, they warrant consideration for subcategorization as a different class or type of kiln. It is likely that these kilns will te nd to be smaller and older kilns. Commenter 0522 agreed that these units represent a different class of kilns. Based on the differences in the emissions profile, and the inability to use the controls EPA has presented for other kilns, the commenter request ed that EPA consider developing a subcategory for kilns with stack temperatures that never reach 300 degrees F.

Commenter 0543 noted that this issue was only identified recently, during the industry ’ s review of the proposed work practice requirements for s tartup and shutdown, and the commenter stated they do not yet have definitive information to provide to the EPA to support subcategorization. The commenter stated their intent to provide the information to the EPA by mid

- to late

- April, which will allow th em time to gather the information on these sources and identify a recommended approach for subcategorization and regulation.

Response 3: The EPA d oes not agree with the commenters ’ request for a subcategory for kilns with low stack temperatures. Commenter 0543 stated that they do not yet have definitive information to provide to the EPA to support subcategorization for kilns with low stack temperatures. Until we have received information to support subcategorization, w e cannot establish a separate subcatego ry for these kilns

. Comment 4: C ommenter 0517 stated the EPA should not set numeric Hg standards because no emissions controls have been demonstrated to be effective in controlling Hg emissions from the brick industry

.

Commenter 0517 noted the BIA believe s that any measured Hg emissions are the result of the input clay rather than any process differences between kilns or installed emissions control equipment (Memorandum to Jeff Telander from the Brick Industry Association MACT Task Force, October 22, 2014, Docket Item No. EPA

- HQ

- OAR

- 2013

- 0291

- 0202). The commenter stated this raises the question of whether any controls available to the industry would have any impact on Hg emissions , and whether they would be “ achievable ” according to the wording of the statu te

.12 Commenter 0517 recommended the EPA subcategoriz e based on raw material input type. According to the commenter, such a subcategorization may need to be combined with a significantly longer averaging time in order to avoid penalizing small businesses for the natural variation of clay at their location. The commenter suggested t he EPA may need to delay promulgation of a Hg emission standard in order to gather the information necessary to establish such a standard.

Two commenters (0517 and 0547) noted the EPA consider ed creating subcategories for Hg that reflect “ the mercury conce ntration of the raw materials in the kiln ’ s clay mine, or geographic location ” (79 FR 75650) , but currently lacks adequate data

.

C ommenter 0547 disputes the EPA ’ s claim that there is insufficient data and argued that :

(1) BIA data provides strong evidence that Hg emissions are tied to the Hg content of the clay raw material. The commenter noted that m ost brick kilns are fired by natural gas or a

non

- fossil fuel , which are inherently low in Hg

(2) BIA ’ s data show significant differences in the Hg content of clay both within particular mines and among the several mines that were tested. T he commenter asserted this data allows the EPA to “ differentiate among types of sources ” for purposes of creating subcategories based on the Hg content of clay.

(3) Alternative sources of clay are not reasonably available to most brick plants for a variety of reasons, including the high costs of t ransporting clay and the character and quality of the finished brick depends of the type of clay used

.
(4) The EPA does no t have the authority to prescribe the use of alternative sources of clay as a means of controlling Hg emissions

. The EPA does not have the authority set a Hg emissions limitation that would require plants to switch to low Hg clay.

Commenter 0547 stated tha t the most authoritative source of legislative history for the 1990 CAA Amendments is the Conference Report, H. Rep. No. 101

- 952, 101 51 Cong. 2nd sess. According to the commenter, one of the issues addressed by the report is the use of mined materials in MACT standard setting. The entire passage is quoted in the commenter ’ s letter as found in the docket, EPA

- HQ

- OAR

- 2013

- 0291.

The commenter further noted that the BIA had raised “ significant technological limitations ” that would prevent the proper applicatio n of EPA Method 29 to emissions from brick plants

. For example, the commenter noted that Method 29 was developed for gas streams with significantly higher concentrations of Hg than typically exists in brick plant emissions. In addition, Commenter 0547 note d that testing for Hg emissions is extremely costly and may be too expensive because of the marginal profitability of most brick plants. For these reasons, Commenter 0547 asserted there is ample justification for EPA to conclude that, due to these technica l and economic limitations, it is not feasible for a typical brick plant to demonstrate compliance with a numeric Hg emissions limitation.13 Response 4: The EPA disagree s with the commenters that there are no Hg emission controls available to the BSCP industry. Activated carbon injection, in concert with fabric filters like those used in the BSCP industry, has been demonstrated in a number of other industries as an effective control for Hg from their process unit s, including a similar process unit (kilns) used in the Portland Cement industry.
With respect to the suggestion that the EPA defer taking action on setting a Hg standard, the EPA notes that it is obligated to take final action to set NESHAP for BSCP facil ities located at major sources on or before September 24, 2015 pursuant to the consent decree in Sierra Club v. EPA , Case No. 08

- 00424 (D.D.C.). Moreover, there are already sufficient stack test data available to set a Hg emission limit now, so there is no need to defer action.

The EPA disagree s with Commenter 0547 that they have proven there is a strong positive correlation between Hg emissions and Hg content of clay. Arguing that most fuels used by brick kilns are low in Hg and therefore, by default, the Hg must be coming from the raw materials, is not a strong positive correlation. Without actual data that demonstrates this correlation, the EPA cannot subcategorize on this basis. However, the EPA agrees that variations in t he raw material can affect the long

- term performance of the best performers when complying with a particular standard. Thus, the EPA has incorporated the data received during the post comment period (as discussed in the docket entry entitled “ Final Maximum Achievable Control Technology (MACT) Floor Analysis for Brick and Structural Clay Products , Section IV.C.”) into the development of the final MACT Hg standard for this category.

The EPA disagree s with Commenter 0547 that there is ample information to differentiate among types of sources. The BIA itself note s that the association ’ s study is still a work in progress. Until comprehensive final results are available, we cannot justify creating subcate gories based on the Hg content of clay. However, t he EPA agree s with the c ommenter that the use of offsite raw materials is not a viable option for the BSCP industry.

The EPA disagree s tha t the measurement methodology for Hg emissions at a brick plant is n ot practical. During the information collection request ( ICR )

, Method 29 was used successfully to determine Hg concentration in the emissions from the brick plants. A majority of the Hg

conc entrations were above the detection limits . Since there are detect able numeric

conc entrations

, a work p ractice standard is not legally permissible.

In response to the commenter ’ s citation to certain legislative history concerning the substitu t ions of materials and mined minerals, the EPA first disagrees this text from the legislative history supports the commenters ’ argument

. First, as the commenter notes, this is legislative history and not statutory language. Indeed, the “ Joint Explanatory Statement ” cited by the commenter carries less weight than the Conference Commi ttee Report, Sierra Club v. EPA , 353 F.3d 976, 988 (D.C. Cir. 2004), and so is not even the most authoritative legislative history. This statement cannot be read to negate either EPA ’ s broader authority to set standards based on the MACT floor under sectio n 112(d) or the specific statutory language in section 112(d)(2)(A) that expressly provides that EPA consider substitution of materials as a measure to reduce or eliminate emissions. See Sierra Club v. EPA , 479 F.3d 875, 882

- 82 (D.C. Cir. 2007) (in calcula ting MACT floors for brick and ceramics kilns, EPA cannot ignore non

- technology measures such as the substitution of clay if those non

- technology measu res affect emissions levels).14 Second, the quoted text itself refers to sources “ engaged in mining, extrac tion, beneficiation, and processing ” of minerals, and does not extend to sources who use the minerals as raw materials to make a final product, such as brick

. The brick manufacturers covered by the se standards are not

“ engaged in mining, extraction, benefi ciation, and processing ” of minerals.

Third, even if this statement superseded the statutory text and case law (which it does not) and if the brick manufacturers covered by this rule would fall within the scope of this text (which they do not), the consid eration of the substitution of materials that this text addresses arises in the context of a beyond

- the

- floor analysis under section 112(b)(2), which is not what EPA is engaged in here. In this rule, EPA is setting standards based on the MACT floor, and is not considering any substitution of materials in setting the standards as part of a beyond

- the

- floor analysis under CAA 112(d)(2)(A) or otherwise.15 5.0 Test Data

Comment 1: Commenter 0554 stated that extending the testing time with Method 23 or other
met hods allows for the taking of a larger dioxin/furan sample. Thus, dioxin/furan emission levels that could not be measured in a one

- hour test can be measured in a two

- hour or five

- hour test. Moreover, it is well established that dioxins/furans can be measur ed down to levels measured in femtograms per cubic meter. [California Ambient Dioxin Air Monitoring Program (Oct. 2004)] In addition, dioxin/furan continuous emission monitors are available, and EPA could use these to measure emissions. [EPA, Environmental Technology Verification Program, Dioxin Emission Monitoring Systems]
Response 1: The EPA thanks the commenter for their comments. The EPA ag r ees that extending the sa mpling time increases the detection limit. In the tests conducted as part of the ICR for dioxin emissions, we required that EPA Method 23 be used and that the source collect a minimum volume of 2.5 cubic meters or have a minimum sample time of 4 hours per run that would result in low method detection lev els (MDLs) in order to increase the possibility of collecting measurable amounts of dioxins and minimize the number of non

- detects. The EPA recognizes the existence of other dioxin measurement methods and yet also recognizes the importance of consistency i n measurements of these low magnitudes as well as the necessity of using the measurement technique for compliance determinations that was used to establish the emissions limit. At this time the EPA holds that M ethod 23 is the appropriate tool for dioxin an d furan emissions determinations. We disagree that dioxin continuous emission monitors are available. There is currently no performance specification (PS) for continuous chlorinated dibenzo

- p

- dioxin (dioxins) or chlorinated dibenz o furan (furans) monitoring . None of the approaches evaluated during the Environmental Technology Verification Program for Dioxin Emission Monitoring Systems met our nominal performance criteria requirement of 20 percent relative accuracy. While EPA believes there is potential to im prove one or more of the continuous monitoring approaches for dioxins and furans to meet our performance requirements, we would need to further evaluate monitoring system performance and promulgate a PS before we would consider requiring continuous monitor ing for dioxins/furans on a broad basis.

Comment 2: Commenter 0543 stated that EPA Method 29, the test method used for gathering the data used to set the standard and required for demonstrating compliance, was designed for significantly higher concentrati on stacks. As a result, the lack of detailed quality assurance procedures that could lead to small errors could have significant impact on final assessments, since the size of the errors can be as large as or larger than the values being measured.
Response 2: The EPA thank s the commenter for their c omment s

. For a majority of the tests, the concentration of the Hg was above the Method 29 detection limits . Therefore, t he detection limits w e re sensitive e nough for the brick plants tested and d o not have a negative effect on measuring HAP metals from Brick sources. There were very few test reports for Hg not detected in any of the 5 fractions of the Method 29 test. The EPA will continue to use Method 29 data for developing MACT floors and use for compliance.

Comment 3: Commenter 0541 stated the existing Hg data collected using Method 29 indicated that the HCl rinse was much higher than the potassium permanganate ( KMNO 4 ) component of the analysis. The commenter stated that the HCl rinse part of the method to capture the last portions of the KMNO 4 solution that adheres to the side of the impinger, and it should be orders16 of magnitude lower than the KMNO 4 solution in total Hg. However, the commenter noted it is as much as two orders of magnitude highe r than the impinger solution in the BSCP data set.

Commenter 0541 noted that one possible explanation for this could be that the KMNO 4 solution was expended during the test due to interference of nitrogen oxides ( NO x ) and carbon dioxide ( CO 2 ), which are also collected in the KMNO 4 solution. The commenter noted while the method does not call for it, most samplers know that the solution turns clear when the solution is expended; these test reports did not have any comments one way or the other. T he commenter stated due to the suspected interference of NO x and CO 2 this would not be advisable for this industry.

Response 3: The E PA thanks the commenter for the ir comments. However, i n reviewing the KMNO 4 fraction data, there were no comments from the testers or laboratories indicating that the permanganate so lution was spent. Also, in comparison to Boilers, the results for b rick kilns are comparable in terms of the ratio of the HCl and KMnO 4 fractions. In general, the largest concentration of Hg was found in the nitric acid/hydrogen peroxide fraction. All five fraction concentrations are combined to get a total Hg concentration. The EPA will continue to use Method 29 data for developing MACT floors and use for compliance.

Comment 4: Commenter 054 1 stated there were no field blanks or proof blanks with the Method 29 Hg data. The commenter found no evidence of the required blanks; the only blanks indicated
were pre

- test filter blanks, post

- test filter blanks as well as field reagent blanks. A ll the blanks were the lab blanks, which did not allow for the correct subtraction of the blanks as allowed for in the method. The commenter asserted that the only way to achieve a true method blank is to take field blanks and proof blanks; the proof blank is obt ained by assembling the clean glassware and then recovering it in the prescribed manner. T he resulting numbers indicate the cleanliness of the sampling equipment and an approximate detection level.

Commenter 0541 stated the field blank is taken after the g lassware has been used for at least one run; it is assembled as a normal run, taken to the test location, leak checked and then recovered as a normal sample. The results indicate train contamination and carry over as well as ambient air components and samp le handling biases; none of these blanks were performed for this data and therefore not calculated for the standards.

Response 4: The EPA thanks the commenter for their comments. W hen following Method 29, f ield and proof blanks are not required . The test r esults are not invalid due to the lack of these types of blanks

. Reagent blanks are required by the method. In terms of “ blank correction ” to sample mass, the only subtraction allowed by the method is residue from the reagent blank. Field blanks are “ infor mative ” (and very good practice) but not required by the method. The correct blank in terms of data correction is the one labeled “ blank ” (FB would mean “ field blank ” )

. The EPA will continue to use Method 29 data for developing MACT floors and use for compliance.

Comment 5: Commenter 0541 stated that the Hg data reported is all total Hg ; it would be impossible to design or evaluate a control device based on this data. M ercury reduction requires differing controls based on the oxidation state of the emit ted Hg ; Method 29 does not differentiate these. T here are methods that do but none of that data is presented.17 Response 5: The EPA thanks the commenter for their comment s . The commenter is correct that Method 29 d id not speciate Hg but g ave a total Hg conce ntration. The EPA only has Method 29 data available for tot al Hg from Brick kilns. The ASTM D6784

- 02 Ontario Hydro Method quantifies Hg in different states, elemental, oxidized, and particulate bound

, however, that method was not a part of the Section 114 testing request. As such, the EPA does not have any oxidation state specific data available for Brick kilns. However, even without speciated mercury data it is still possible to develop cost estimates for potential controls based on typical emission control designs from other industries.

Comment 6: Commenter 0541 stated the detection limits and blanks presented in the Method 29 Hg results are only analytical data; no field or method detection data was presented. The
commenter noted the method stated variation in the metal analysis but did not include the Hg analysis.
Response 6: The EPA disagrees with this comment

. The EPA used the detection limits that were made available by the laboratories performing the analyses for both the me tals and the Hg fractions

. The EPA’s electronic reporting tool ( ERT ) was used by testers to calculate the emission concentration and rates utilizing the field sampling and laboratory data. If both fractions had non

- detectable quantities, the analytical detection limit was multiplied by the field sampling volume to calculat e the test

- specific detection limit. This data was presented in the performance test reports.18 6.0 Type of Standard

Comment 1: Commenter 0543 stated that the use of work practices is justified under CAA section 112(h) for the reasons detailed in the prea mble and commended the EPA on their use. Commenters 0543 also stated that the use of work practice standards should be expanded. Commenters 0555, 0556, and 0558 supported the EPA ’ s proposal of work practice standards and noted that their concerns with othe r provisions of the proposed rule do not take away from their support of work practice standards.
Response 1: The EPA appreciates the commenters ’ support for the use of work practice standards in the BSCP rule. Our response regarding Commenter 0543 ’ s reque st for expansion of work practice standards is presented elsewhere in this section.

Comment 2: Commenter 0554 stated that the work practice standards for dioxin/furan emissions from brick tunnel kilns violate CAA section 1 12(h) and section 1 12(d) because t he EPA did not identify any particular technological limitation associated with the measurement method

. The EPA ’ s argument that some test results were below the detection limits does not meet the relevant statutory standard. The EPA did not claim that it is not practicable to apply measurement technology to dioxins/furans

. M easurement technology has been applied to dioxins/furans and generated significant emissions test data. T he commenter asserted that setting work practice standards in lieu of emission s tandards for dioxins/furans would be unlawful and arbitrary.

U nder CAA section 1 12(h), the test is whether “ the application of measurement methodology to a particular class of sources is not practicable. ” The EPA did not identify any class of sources to wh ich measurement methodology for dioxins/furans is not practicable CAA section 1 12(h) does not allow the EPA to set work practice standards whenever a number of emission tests falls below detection limits. The EPA ’ s claim show s only that some sources ’ emiss ions are lower than the detection limits for some measurement methods, not that “ measurement methodology ” for dioxin/furan emissions from brick tunnel kilns is not practicable.

The commenter stated that the fact that some units recorded test results below the particular detection limit does not show that application of measurement methodologies is impracticable

. The commenter noted that some sources use d the cheapest and least accurate tests and submit ted data that lacked precision and incorporated high det ection limits. The EPA cannot use these imprecise data as an excuse to avoid setting emission standards because t he measurement methodologies that allowed many other kilns to use much lower detection levels are applicable to all sources.

Commenter 0554 qu oted Sierra Club v. EPA , 479 F.3d 875 , which vacat ed prior work practice standards for certain brick and clay ceramics plants on holding that the lack of available data does not provide a valid justification for work practice standards under CAA section 1 1 2(h)).

The commenter also noted that the CAA expressly authorizes the EPA to issue a “ prohibition ” on emissions where achievable

, and a fortiori , the EPA can issue standards at a specific detection limit higher than zero even if emissions cannot be measured below that detection limit. . Even if the test results that fall below a particular source ’ s detection limit are not used for the purposes of standard

- setting, the EPA must base floors on the sources for which the Administrator does19 have usable em issions data pursuant to CAA section 1 12(d)(3)(A)

. Since t he EPA has emissions data for dioxins/furans that are above the detection limits and has acknowledged that where

“ emissions can be precisely measured for at least some units in [a] subcategory ... t he statutory test for establishment of work practice standards

-- i.e. , that measurement of emissions is impracticable due to technological and economic limitations

-- is not met. ” National Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial, Commercial, and Institutional Boilers and Process Heaters, 76 FR 15608, 15640 (Mar. 21, 2011).

The commenter stated that the fact that some kilns might always record emission levels below their particular detection levels is irrelevant since d oes not show the measurement methodology is impracticable, but merely the kiln ha s low emission levels, high detection levels, or both. The commenter asserted that low emissions from brick tunnel kilns can be measured by methods in use today and noted the EPA propos ed roller kilns and first

- fire tunnel kilns at ceramic facilities measure dioxins/furans using EPA Method 23 or an approved alternative method ( 40 CFR 63.7(f) ) . If EPA Method 23 and alternative methods are technologically feasible for clay cerami cs first

- fire tunnel kilns, then they should also be feasible for brick tunnel kilns.

The commenter stated that w hatever imprecision is associated with monitoring emissions at levels near the detection level can be addressed by further statistical manipula tions, adjusting the limit ( e.g. , with a safety factor) that accommodates any uncertainty ( e.g. , 50 percent above the detection level), or establishing monitoring protocols that reduce the uncertainty to an acceptable level.

The commenter stated that even if EPA could not for some reason set standards based on the sources achieving emissions below the detection level, the EPA still has data above the detection limit that represents greater than 12 percent of the sources with data. CAA section 1 12(d)(3) dire cts EPA to base floors on emissions achieved by the best performing sources “ for which the Administrator has emissions information. ” The EPA has acknowledged that where “ emissions can be precisely measured for at least some units in [a] subcategory ... the statutory test for establishment of work practice standards

-- i.e. , that measurement of emissions is impracticable due to technological and economic limitations

-- is not met. ” 76 FR 15640. Thus, the EPA could base standards on these emissions and specif y a test method that would detect emissions at these levels.

Finally, Commenter 0554 argued the EPA had claim ed but failed to explain why methods for dioxins/furans would be economically infeasible. Even if the EPA is able to point to additional costs associated with use of a measurement methodology that would not demonstrate that economic limitations render the measurement of emissions “ impracticable. ”

Response 2: T he EPA disagrees with the c ommenter ’ s objections to work practice standards for dioxins/furans ( D/F ) from BSCP tunnel kilns. In the tests conducted as part of the ICR for dioxin emissions, the E PA required that EPA Method 23 be used and that the source col lect a minimum volume of 2.5 cubic meters or have a minimum sample time of 4 hours per run that would result in low MDLs in order to increase the possibility of collecting measurable amounts of dioxins and minimize the number of non

- detects. The EPA recogn izes the existence of other dioxin measurement methods and yet also recognizes the importance of consistency in measurements of20 these low magnitudes

, as well as the necessity of using the measurement technique for compliance determinations that was used to establish the emissions limit. At this time

, the EPA holds that M ethod 23 is the appropriate tool for dioxin and furan emissions determinations.
The majority of the data collected in order to set the D/F standards for B rick MACT are at levels below the c apability of the analytical and stack test methods to detect emissions of these compounds. Much of the test data are labeled as being below the method detection limit and the remainder of the data is often flagged as being below the level the laboratory ca n report with confidence.

The EPA based the need for implementing a work practice based on the low levels of emitted dioxin and furans and the resulting ability to accurately quantify and set emission limitations. In taking this action, the EPA recognize s that low emission levels are the result of good combustion practices. The EPA came to this same conclusion for electric utility boilers and also implemented dioxin and furan good combustion work practices in that rule. However, the clay ceramic dioxin da ta was detectable by Method 23 , and t herefore, it does not qualify for implementing a work practice.

Comment 3: Commenter 0554 stated that the proposed work practice standards for brick periodic kilns violate CAA section 1 12(h) and section 1 12(d).

The commenter disagreed with the EPA ’ s reasons for setting work practice standard because they do not satisf y the CAA section 1 12(h) requirement that measurement methodology “ is not practicable due to technological and economic limitations

. ” First, that br eakthrough “ can occur ” at times, which would require retesting, does not present a technological hurdle rendering the methods impracticable for the entire class of sources; it only means that additional time and costs may have to be expended in some instan ces. The commenter noted that the EPA had not demonstrated the additional costs or additional manpower for the methods make the measurement methodology not technologically or economically practicable

.

Commenter 0554 stated that although t he EPA ’ s data sho ws emissions spikes of HCl and HF, the EPA never asserted that emissions of other regulated pollutants would encounter the same issue. To the contrary, the EPA acknowledged that different methods ( i.e. , EPA Methods 5 or 17) would be used to test for PM as a surrogate for non

- Hg HAP. 79 FR 75645. The commenter asserted that w ork practice standards are only allowable where it is not feasible to prescribe or enforce “ an emission standard ” for control of “ a hazardous air pollutant or pollutants. ” The
commenter asserted the EPA must make a supportable determination that an emission standard is infeasible for each hazardous air pollutant for which it adopts work practice standards

. Commenter 0554 agreed with the EPA that Fourier transform infrared (FTIR) ( EPA Meth od 320 ) is a practicable alternative to Methods 26 and 26A, but disagreed with the EPA ’ s determination that economic limitations prevent the application of FTIR. The commenter argued that Congress did not allow the EPA to set work practice standards in lie u of numerical emission limits because the costs of compliance would be too high . The commenter asserted that Congress required MACT

- based emission limits be set at least as stringent as the floors, regardless of cost.

Commenter 0554 asserted that the EPA failed to explain why the cost

- to

- sales and cost

- to

- profit ratios it estimated would be economically infeasible. In addition, the cost ratios that the EPA21 calculated are on an individual kiln basis, yet the EPA used them to conclude that the ratios would f orce firm closures, without considering cost

- to

- sales or cost

- to

- profits on a firm

- wide scale. The commenter argued that c ost data for individual kilns is not interchangeable with cost data on firms.

The EPA asserted that variability would interfere with s tack testing. However, the commenter noted that emissions can be variable over time a nd noted stack testing will be used by for tunnel kilns. The commenter stated that the EPA failed to rationally explain why stack testing is practicable for tunnel kilns b ut not for periodic kilns, as they both can have variable emissions.

Response 3: The EPA disagree s with the commenter that testing of periodic kilns using Method 26 or 26A poses no technological or economic limitation. As noted in the subject memo, due to the variations in emissions during firing cycles and variations in emissions across the tests,

“ sampling a single kiln cycle might not be adequate for characterizing periodic kiln emissions and would mean testing each periodic kiln for more than 100 hours [emphasis added] in order to determine an emission rate that is representative of normal operating conditions. Furt hermore, because periodic kilns are used to fire specialty products that may have significantly differently time

- temperature profiles, it may be necessary to test the same kiln multiple times to characterize emissions from different types of products

. ” Add to that the possibility that such lengthy testing might have to be redone in the event of HCl breakthrough, and it is clear that Method 26/2 6A testing is not a practical method for testing acid gas emissions from periodic kilns. Consequently, the rest of our analysis focused on FTIR as the only practical alternative left to review.

While the commenter is correct that no costing was done for Me thod 26 or 26A, the exorbitant costs that would be expended for such testing are self

- evident, given the extremely lengthy period of testing that would be required. However, for purposes of this analysis, we estimated a cost of $46,000 for 100 hours of tes ting, which is likely to be an underestimate, given the need to test the same kiln multiple times to characterize the emissions from different types of products and the possible of retesting due to HCl breakthrough. Assuming the same kiln is tested three
t imes for three different products and then retested due to breakthrough, the cost of Method 26/26A testing for a single kiln could be as high as $276,000. It should also be noted that some BSCP facilities have multiple periodic kilns

-- on average, eight per facility for BSCP facilities with periodic kilns.

The same argument about cost could also be made for FTIR, since t he cost for testing by FTIR is estimated to be $ 49,750 for a single 5 0

- hour kiln cycle. To develop a representative emission rate, it might be necessary to test for two cycles at a cost of almost $ 100,000

, and the cost would be even higher when done again for different products. If testing were extended into the cooling period, the costs would be even higher. A dditional costs would also be inc urred for testing the kilns for PM and Hg emissions, which would have to be tested using a manual test method , such as EPA Method 5 /29, multiple times over very lengthy periods. This amount of testing and retesting for such lengthy periods poses substantial technological and economic limitations. Therefore

, we clearly believe that the section 112(h) criteria for setting work practice standards have been met.22 The cost to sales ratios were calculated on a firm basis rather than a kiln basis. The RIA clearly states this in Section 5.3.1 and gives the details of how the upper and lower bound estimates of closures were calculated. The section also addresses why the estimated range of closures might be too high or low.
Finally, the EPA disagree s w ith the commenter ’ s contention that the emissions variability for periodic kilns is comparable to that for tunnel kilns. As stated above, periodic kilns have variations during firing cycles and variations in emissions across tests. These variations are sub stantially greater than those observed for continuously operating tunnel kilns. In addition, unlike tunnel kilns, periodic kilns are used to fire specialty products that m ay have significantly different time

- temperature profiles , which also increases varia bility for a particular periodic kiln

. Comment 4: Numerous commenters (0514

- 0516, 0520, 0521, 0522, 0523, 0528, 0529, 0536, 0537, 0543, 0545, 0548, 0550, 0551, 0552, 0555, 0556, 0558, 0560, and 0562 ) stated that the EPA should replace the numeric limits for Hg and non

- Hg HAP metals with work practice standards under the authority of section 112(h) of the CAA

. Section 112(h) allows for the use of a work practice standard when compliance demonstration is technically and economical ly impracticable. Commenters asserted that the use of work practices is justified because the small uncontrolled emission levels and small potential incremental reductions would be technically and economically infeasible to demonstrate on a consistent and repeatable basis.

C ommenter 0543 stated that there is adequate information available for the EPA to conclude that a numeric emission limit is both technically and economically impracticable to enforce with reasonable confidence and repeatability and provid ed, along with other commenters, the following reasons that work practice standards are appropriate and necessary.

Commenter 0543 noted that test data submitted by the BSCP industry, developed by numerous stack testing firms and testing labs across the cou ntry, required significant manipulation to arrive at revised “ usable ” data. This is largely because data are very close to the detectable/measurable limits. Many BSCP companies will not have the technical expertise onsite to make these same adjustments. Th erefore, they will be unable to assess their own compliance status. The commenter contended that this makes the standard technically infeasible to enforce.

C ommenter 0543, along with Commenters 0522 and 0523

, stated that the EPA also did not account for th e additional cost of hiring consultants to conduct the compliance activities, review the test results to ensure their validity, and make any necessary test data adjustments. Commenter 0543 stated that these additional expenses would make compliance demonst rations economically infeasible.

Commenter 0543 noted that the EPA identified a number of issues with stack test reports, such as sample contamination, manganese contamination, and filter failure. If any of these errors are identified after a compliance st ack test is completed, the facility will have to rerun a stack test to attempt to get three acceptable runs. The commenter asserted that these expenses make compliance demonstrations economically infeasible.

Commenter 0543 , along with commenters 0527 and 0 558, also expressed concern about the reliability of the Method 29 stack test itself. C ommenter 0558 noted that stack testing results for23 Hg cannot be consid ered 100 percent reliable, as Method 29 was designed to be used on significantly higher concentrati on streams. Commenter 0527 asserted that there is too much uncertainty in the consistency of the stack test results to place numeric emission limits on BSCP plants.

Commenter 0553 asserted that there is not enough information or data available at this time to understand the true form or amounts of Hg being emitted to justify a specific Hg limit. Stack testing results from the EPA ’ s own 2010 survey revealed obvious inconsistencies between testing firms and laboratories. These inconsistencies lead to discrepa ncies in the values reported that were in many cases below the detection levels of Hg . Imposing a strict numeric limit on Hg without fully understanding its true form, quantity, and controllability within the BSCP industry is not responsible policy. A fair estimate of costs to control Hg at such low levels cannot be developed when there is not a true basis of understanding of what the EPA and industry are trying to control. Commenter 0553 requested that the EPA reevaluate the numeric limits on Hg and consid er removing them from the rule until a better understanding of Hg is established within the BSCP industry, or at the very least, consider increasing the proposed limits to more reasonably attainable levels while still allowing faciliti es to operate efficie ntly.

M ultiple commenters (0516, 0520, 0521, 0522, 0523, 0527, 0536, 0537, 0545, 0548, 0550, 0551, 0552, 0553, 0555, 0556, 0558, 0562 , and 0563 ) stated that a plant ’ s ability to meet the proposed Hg and non

- Hg metal HAP limits would be completely dependent on the trace elements in the mined raw material. Commenter 0516 added that Hg may be present in the natural gas used to fire the commenter ’ s kilns. Commenter 0563 n oted that Hg is typically present in extremely small quantities if at all; in many tests, the levels are undetectable. Commenter 0522 noted that the small amount of data used to set the proposed limits d id not take into account the variability of the mined raw materials and stated that

, at the very least, this is a flawed assumption due to the variability of the mined materials.

Commenter 0527 noted that m ost BSCP plants use raw material that is located near the plant site. Since dirt and brick both have lo w values to weight, no plant can afford to switch its source of raw material simply to try and comply with EPA emissions limits. There are no alternative operating methods that can change the raw material or reduce the minerals contained within it. Comment er 0558 noted that the BSCP industry is conductin g a raw material study and is learning that Hg contents vary across raw material type (clay, shale), by facility location, and even possibly within a mine.

Commenter 0543 sta ted that EPA is precluded from b asing any MACT limits on mined materials. However, the commenter stated that the industry is ready to work with EPA to establish work practice limits that are reasonable and meet the requirements of section 112.

M ultiple commenters (0516, 0520

- 0523, 0527, 0529, 0530, 0536, 0537, 0543, 0545, 0548, 0550

- 0553, 0555, 0556, 0558, 0559, and 0562) also asserted that the EPA failed to demonstrate that the controls for Hg and non

- Hg HAP metals that EPA cited are warranted or effective for the BSCP industry

. Commente r 0522 added that rather than the fabric filter used as a cost basis in the proposed rule, many kilns would require a DIFF, since the small amounts of HF and HCl in the gas stream would need to be controlled to maintain the integrity of the DIFF. Commenter24 0537 specifically noted that no one has ever installed a stand

- alone fabric filter ( FF ) without the dry injection system and no one has installed a fabric filter after a DLA in the BSCP industry, so there is no way of knowing that th is would actually work

.

Commenters 0537 , 0543, and 0562 noted that there is no way to know if activated carbon injection ( ACI ) would work with the low Hg concentrations and other loadings in kiln exhaust airstreams. Commenter 0559 understood that there have never been Hg controls on a BSCP kiln; the c ommenter asserted that the EPA should only be permitted to require control when it has been demonstrated that control is possible. According to Commenter 0543, if the ACI does not work, then the cost effectiveness of controlli ng Hg is infinite. If the cost effectiveness is infinite due to no available control, there is no technically or economically practicable way to demonstrate compliance with the limits.

Commenter 0545 expressed concern that here is simply no way to know that the technology proposed by EPA will get the reductions necessary to comply. Installing an “ add

- on ” to the existing DIFF will be operationally difficult, economically unfeasible, and f orce the company to commit more time, talent, and treasure to compliance and testing than the limited staff is capable of, and in the end, the device may not work. The commenter also noted that they consulted with the DIFF manufacturer, and the manufacture r expressed great concern that any Hg reduction equipment may cause underperformance of the scrubbing of the HAP that it was built to control, and that system replacement may be necessary. If replacing the DIFF altogether is necessary to achieve the Hg lim it, the commenter stated they would cease their business operations.

Commenter 0559 noted that since they provide a cosmetic product to homeowners and builders and they understand the vast effect of small changes of airflow in the tunnel kiln, they are

con cerned that the addition of a control device will make their product less desirable

.

C ommenters noted that the proposed rule includes limits that are based on very little data, including just a single controlled source for small kilns used as the basis for Hg limits. However, based on this single controlled source meeting the Hg limit, the EPA assumed that all uncontrolled small kilns will meet the limit. The EPA also assumed that the majority of untested large sources will meet the limit. M ultiple commente rs ( 0516, 0520, 0522, 0527, 0537, 0545, 0551, 0553, 0555, 0556, 0558, 0562 , and 0563) asserted that they will not or may not be able to meet the proposed Hg and non

- Hg HAP metals limits with current control configurations, and the installation of controls would be expensive and may cause their plants to shut down

. Multiple commenters (0516, 0527, 0529, 0530, 0545, 0551, 0553, 0558, 0559, 0562, and 0563) expressed concern about the expense of installing unproven controls if they cannot comply with
current c ontrols. Commenter 0530 stated that

, even assuming that technology is available and is effective, many companies in the BSCP industry will be unable to obtain the financing required for add

- on controls and will therefore be forced to shut down . Commenter 0 516 stated that the cost would be crippling to the company, and would factor into management ’ s decision of whether or not to re

- open many of the currently closed plants. Commenter 0527 noted that they will simply shut down if it is determined that the plan t is not in compliance with the BSCP MACT standards contained in the final rule.25 Commenter 0563 stated that if they cannot meet the Hg limits without control, they assume that all of their currently uncontrolled kilns would need to install DIFF with ACI an d the two DLA

controlled kilns would need to be retrofit with the same systems. The commenter asserted that they do not agree with EPA ’ s belief that stand

- alone fabric filters are demonstrated, so they used the EPA ’ s estimated costs for DIFFs with ACI for all kilns. The commenter also questioned the low cost of ACI systems but did use those numbers in their estimates. The commenter stated that the EPA ’ s estimated installed cost of the controls they would need is around $17.5 million and the estimate of the annual operating cost of these controls would be an additional $5.7 million. Industry

- wide calculations show the cost per ton of HAP reduced would be in the millions of dollars. The commenter asserted that the cost

- to

- benefit ratio of this approach is unre asonable and it will be economically impossible for this company and other companies in the industry to implement this part of the rule as proposed. The financial burden this rule will impose will force doors to close in many companies, possibly the commen ter ’ s. At a minimum, the commenter noted they have kilns that will never reopen if the upfront capital cost estimate is correct. Employees may lose their jobs.

Multiple commenters (0516, 0520, 0521, 0523, 0529, 0536, 0537, 0545, 0548, 0550, 0551, 0552, 055 3, 0555, 0556, 0558, 0562

, and 0563 ) also noted that the levels of potential emission reductions from BSCP facilities, by the EPA ’ s own estimates (i.e., 2

- 6 pounds of Hg per year and 150

- 380 pounds of non

- Hg HAP metals), are small. However, the commenters noted that the EPA assumed that multimillion dollar controls could be financed and operated to get the small reductions claimed by this rule. Commenter s stated that there would be no benefit to human health and th e environment resulting from the se expendit ures. Commenters 0523 and 0545 stated that the stack tests would also be very costly and would create a significant financial burden simply to determine the levels of th es e HAP. Commenters 0545 and 0562 asserted that costs in the millions or hundreds of mi llions of dollars per ton clearly indicate that EPA may have missed creating a necessary subcategory.

Finally, several commenters (0516, 0527, 0543, and 0563) provided suggestions for Hg work practice standards. Commenter 0543 stat ed that work practices could take several approaches. The work practices that were proposed in th e rule for dioxin/furan, i.e., burner checks, would ensure effective production of brick and reduce any additional trace Hg emissions that would occur for replacing lower quality bri ck with acceptable brick. Commenter 0527 requested that the EPA modify the rule to include a work practice standard which would establish the best operating practice for BSCP plants and monitor the compliance of the plants within these reasonable standards

. Commenter s 0516 and 0563 stated that work practices for Hg could be as simple as the work practices in the Boiler MACT , alone or in combination with facility

- specific measures. According to Commenter 0516, th ese measures could involve a requirement to se t bench

- mark Hg levels using raw material mass balance measures at each facility. Commenter 0563 suggested some assessment of the Hg content of the raw material for individual plant locations

, with a more extensive material monitoring plan when significant amounts of Hg are found.

Response 4: The EPA does not agree with the commenters ’ request for EPA to replace the numeric limits for Hg and non

- Hg HAP metals with work practice standards , for the reasons discussed in the paragraphs below. We have prepared r esponses to commenters ’ arguments26 against emission limits for Hg and non

- Hg HAP metals and their arguments supporting work practice standards for those pollutants.

The EPA disagrees with Commenter 0543 that significant data manipulation is required for BSC P companies to determine their compliance status with the Hg and non

- Hg metals emission limits . The types of data manipulations necessary to determine MACT floors are not required when comparing compliance testing results to an emissions limit.

The EPA als o disagrees with commenters that external consultants must be accounted for in the cost estimates for complying with the Hg and non

- Hg metals emission limits. As commenters have noted elsewhere in th eir comments , such costs would be company

- specific, so th e extent of these costs and the number of affected facilities would not be clear.

With regard to the issues with stack test reports that Commenter 0543 noted, in its test data review, the EPA did discard test runs when the EPA r eference method was not foll owed or the required quality assurance ( QA ) elements within the method failed, or sample contamination occurred. The EPA generally requires three test runs fo r demonstration of compliance , but d elegated authorities can approve less than three test runs at their discretion . Conse quently, facilities may not need to rerun stack tests to get three acceptable runs.

The EPA disagrees with commenters that the measurement methodology for Hg emissions at a BSCP plant is not reliable

. During the 2010 t esting program, Method 29 was used successfully to determine Hg concentration in the emissions from the BSC P plants. M ethod 29 w as sensitive enough to have a majority of the test repo rt above detection levels. Accordingly, because the Hg is at measurable l evels, work practice standards are not applicable

. With respect to the suggestion by Commenter 0553 that the EPA defer taking action on setting Hg emission limit s until more information becomes available , the EPA notes that it is obligated to take final ac tion to set NESHAP for BSCP facilities located at major sources on or before September 24, 2015 pursuant to the consent decree in Sierra Club v. EPA , Case No. 08

- 00424 (D.D.C.). However, the EPA agrees with commenters that variations in the raw material ca n affect the long

- term performance of the best performers when complying with a particular standard. Thus, the EPA has incorporated the data received during the post

- comment period into the development of the final Hg emission limits for the BSCP source ca tegory ; see Final Maximum Achievable Control Technology (MACT) Floor Analysis for Brick and Structural Clay Products Manufacturing for more information

. 2

The EPA agrees with Commenter 0527 that the use of offsite raw materials is not a viable option for the BSCP industry. We are not requiring the use of offsite raw materials in this rule.

The EPA disagrees with commenters that there are no demonstrated Hg or non

- Hg HAP metals emission controls available to the BSCP industry. Activated carbon injection and fabric filters ha ve been demonstrated in a number of other industries as an effective control for Hg and non

Hg HAP metals from their process units, including a similar process unit (kilns) used in the

2 Raymond, G., and K. Sroka. Final Maximum Achievable Control Technology (MACT) Floor Analysis for Brick

a nd Structural Clay Products Manufacturing . Memorandum from Gabrielle Raymond and Kristin Sroka

, RTI International , to Sharon Nizich

, EPA/OAQPS/SPPD . September 24, 2015

.27 Portland Cement industry. However, it is up to each f acility to determine the type of emission control that works best for their particular situation.

Concerning the issue cited by Commenter 0559 that the installation of a control device would have significant impact upon the products due to airflow , and, th erefore, on the ability to successfully market their products , the EPA has not receive d any data to support the
commenter ’ s contention. We also note that a number of BSCP plants have retrofitted DIFFs with no apparent adverse impact. 3 Similarly, we have no t received any data to support Commenter 0545 ’ s contention that the addition of Hg control equipment would cause the DIFF to underperform, requiring replacement of the DIFF control device.

With regard to commenters ’ concerns that they may not be able to co mply with the Hg and non

Hg HAP metals emission limits with their current controls and may need to install expensive controls to meet the limits, it should be noted that under section 112 we cannot consider costs and other impacts when establishing MACT fl oor requirements . However, t he EPA has taken significant steps to minimize the impacts of the rule on the small entities that are prevalent in the BSCP industry, while still achieving the objectives of the rule. In particular, the EPA has includ e d kiln size subcategories in the Hg and non

- Hg metals emission limits

, incorporate d raw material variability factors into the Hg emission limits, and reevaluat ed stack test data used in developing the MACT floor PM surrogate emission limits

. Regarding the c ontention by Commenters 0545 and 0562 that we may have missed creating a necessary subcategory, we evaluated public comments requesting a subcategory based on the Hg content of clay , but insufficient data are available to support subcategorization.

As note d elsewhere in this document (see section 15.2) , t he EPA understands that firms may have difficulty obtaining longer

- term financing needed to buy the control equipment and make process changes needed to comply with the proposed Hg and non

- Hg HAP metals emi ssion limits . The EPA ’ s closure estimates may be an underestimate because of the difficulty in obtaining financing at a 7 percent interest rate , or they might be an overestimate if the industry has become more robust by 2018 when the control must be in pla ce. O verall market impacts for the standard are estimated to be a less than 2 percent national average price increase and a less than 2 percent national average reduction in production. Please see the RIA, Regulatory Impact Analysis: Final Brick and Struct ural Clay Products NESHAP found in the docket for more details.

Regarding commenters’ suggestions for work practice standards, the EPA notes that if a numerical emission limit can be supported under section 112(d), a work practice standard is not legally p ermissible.

Comment 5: Commenter 0543 reiterated a previous suggestion that the EPA should set a health

based emission limit for Hg because it is a threshold pollutant. Commenter 0543 asserted that

3 Holloway, T., and K. Sroka, RTI International. Updated Inventory Database and Documentation for Brick and Structural Clay Products Manufacturing Final Rule . Memorandum from Thomas Holloway and Kristin Sroka, RTI International, to Sharon Nizich, EPA/OAQPS/SPPD. September 24, 2015.28 given that Hg has a reference concentration, there is a l evel deemed safe by EPA with regard to human health. Therefore, the commenter requested that the EPA fully consider establishing a health

- based emission limit for Hg emissions in lieu of a MACT floor

- based emission limit. A methodology similar to that perf ormed for the acid gases using acute health indices could be used to provide an allowable emission rate, below which, exposures would be considered safe.

Commenter 0547 agreed, adding that EPA has concluded that Hg is a threshold pollutant. Commenter 0547 stated that as with the proposed health

- based emission limit ( HBEL ) for HAP acid gases, the EPA could easily use this well

- established threshold for Hg , in conjunction with the site

- specific data the EPA has collected on virtually all of the potentially af fected brick plants, to determine a health

- protective alternative emissions limitation for Hg emissions.

Commenter 0543 also included a copy of a December 2013 memorandum they sent to the EPA outlining the results of modeling of Hg emissions from the 83 pl ants operating at the time. Specifically, the maximum individual non cancer health risks posted by existing major source kilns were modeled using the EPA Human Exposure Model version 3 (HEM

- 3) . The memorandum showed that all facilities in the BSCP source c ategory, under the worst case meteorological conditions and operating at full capacity, never exceeded a chronic neurological hazard index ( HI ) of 0.003, clearly below EPA ’ s “ safe ” level of 1. Further, 88 percent of the facilities modeled below an HI of 0.001.

Commenter 0543 noted that in order to provide a complete assessment for the source category, the kilns with no data were modeled with “ worst case ” default values, which are so conservative that it is unlikely that a kiln with such stack parameters could actually produce brick due to insufficient airflow. Emissions data used for each facility were based on site

- specific information, where available. If no data were available, in dustry average values were used.

Response 5: T he EPA disagrees with the comment that a health

- based emission limit should be established for Hg

. Also, the comment that the EPA has derived a reference concentration for Hg is incorrect. The EPA has derived a reference dose (for the oral route) for a form of Hg

, methyl
mercury , and in this assessment the EPA notes that there is no evidence for a biological threshold for the critical effect of neurological deficits in children in the principal studies of the Integrated Risk Information System ( IRIS ) assessment for this chemical. In addition, methyl mercury has been classified by the EPA as a possible human carcinogen. 4 For these reasons the EPA does not consider Hg a threshold pollutant.

Comment 6: Commenter 0534 requested alternative compliance options regarding the exhaust from a new subcategory of wood byproduct dryers. As an alternative to numeric limits for these sources, the commenter suggested implementing work practice standards, as this is the most reasonable and environmentally beneficial option. Implementing a numeric standard for these sources could be both technically infeasible and cost prohibitive.

The commenter stated that a primary constituent of this work practice standard would be to efficiently maintain and operate the dryers in such a way as to minimize the hours that they have

4 Integrated Risk Information System Assessment for Methylmercury. 2001. Available at http://www.epa.gov/iris/subst/0073.htm

.29 to operate. During a recent permit renewal at Commenter 0534 ’ s Salisbury plant, the company conducted extensive air modeling to demonstrate compliance w ith the air toxic standards in North Carolina. The company was able to demonstrate compliance with these stringent concentration based health and environmental standards using the operating scenario described above. The commenter asserted that this demonst ration supports the claim that the environmental benefit to imposing numeric limits on the wood byproduct dryer exhaust is minimal if at all.

Response 6: The EPA disagrees with the commenter ’ s request. The commenter has provided no data to justify adding a new subcategory of wood byproduct dryers . In addition, the commenter has provided no information to support setting a work practice standard for this emission unit under section 112(h).

Comment 7: Commenter 0522 asserted that work practices are warranted for the subcategory of kilns with low stack temperatures because the small uncontrolled emission levels and small potential incremental reductions would be technically and economically infeasible to demonstrate on a consistent and repeatable basis. The com menter requested that the EPA consider that work practices would meet the requirements of the CAA while still allowing facilities to operate.
Response 7 : The EPA disagrees with the commenter ’ s request. As noted in a previous response, the EPA do es not yet have definitive information to support subcategorization for kilns with low stack temperatures. We cannot establish a separate subcategory for these kilns until we have received information to support such subcategorization.30 7.0 MACT Floors

7.1 Determin ing Sources in Floor Pool

A major public comment on determining sources in the MACT floor pool and the EPA ’ s response to that comment can be found in section V.A of the preamble to the BSCP final rule. The remaining public comment on that subject and EPA ’ s response is presented below.

Comment 1 : Commenter 0540 asserted that work practice standards for Hg should be considered in a final rule; however, the commenter provided recommendations for alternate consideration of how the numerical limits are determine d in the event that the EPA does not agree to set work practice standards. The commenter stated that the primary underlying concern regarding the calculation of Hg upper prediction limits ( UPLs ) stems from EPA ’ s seemingly arbitrary selection of the number of sources to be included in the various UPL floor pools used in the calculation of proposed emission limits as well as in the discussion of the various alternate floor calculations that were not used in the final proposed limits. These variations range fr om PM UPL calculations based on 27 sources representing 12 percent of the “ total source population ” of 227 kilns to only 3 sources representing 12 percent of 19 kilns (20 kilns with one test being 2 co

vented kilns and split as 2 in database) “ sources with available data ” in Hg UPL calculations for large kilns. The EPA should include all data from the best performing sources in a UPL floor determination.

Commenter 0543 stated EPA correctly describes why it is appropriate to base the MACT floor for PM on the top performing 12 percent of sources in the category (or subcategory), as opposed to 12 percent of the sources for which there is stack test data. The commenter noted that first, the dataset was knowingly skewed by the EPA to only include the best perform ing sources for PM and Hg , i.e., the DIFF

- controlled systems; this was discussed at length during the ICR testing conducted for this proposed rule. S econd, while stack test data may not be available for each source in the category or subcategory, there is sufficient information to estimate the emissions of each unit since size, fuel, and other emissions information is available. The commenter requested that EPA extend the approach taken for PM to the approach for calculating the MACT floor for numeric Hg limits, if a numeric limits remain in the rule; this was specifically discussed with EPA during the ICR process and during a December 1, 2010 meeting w ith EPA upper management, when EPA assured industry that all tests would be included.

Commenter 0540 stated all but one of the Hg stack tests were done as a CAA s ection 114 mandate from the EPA; the sources were handpicked by the EPA and all included APCDs

-- all DIFFs and one electrostatic precipitator ( ESP ) . The commenter stated that in verbal discussions with the EPA, BIA asked that some DLAs and uncontrolled sources be included, and it was stated that it made no sense to test what was not thought to be best performing. The commenter recognized that the EPA was somewhat limited by the 9 entity hurdle in demanding testing; however, many of the entities included in the 114 demand have DLAs and uncontrolled kilns that could have been included in the testing request. The commenter noted that the EPA stated that the industry was welcome to test any kilns they wanted included; however, given $15,000 Method 29 testing costs and the economic times of 2010 just doing what was mandated in the 114 requirement was cha llenging for the industry as a whole. The commenter stated in addition, in a meeting with the EPA in Washington, DC on December 1, 2010, the EPA stated that their31 intention was to use all data from the tests since these units represented the best performin g sources. The commenter stated were there any thought that EPA would use only 12 percent of the sources with data as opposed to 12 percent of the source category kiln population as was done in the 2003 rule, the industry would have definitely considered t he ramifications of this limited testing and would have possibly pursued further testing options in spite of the costs. The
commenter stated the EPA ’ s comments at that meeting were critical to the BIA ’ s decision regarding additional testing.

Commenter 0540 stated in the proposed rule the EPA has demonstrated that DIFF controlled sources are the best source performers for PM of which 27 sources are used in the PM floor pool. The commenter stated of these 27 there are 13 DIFFs with Hg data plus the two small Belden kilns vented through an ESP discussed as being best performers in the proposed rule. The commenter stated as a minimum this should dictate the use of at least 15 sources in a Hg floor pool UPL determination.

Commenter 0540 stated the proper use of H g test data available to the EPA results in UPL limits of 2.24E

- 04 lb/ton, 85.28 micrograms per dry standard cubic meter ( μg /dscm ) and 1.53E

- 03 lb/hr as contrasted to the proposed rule limits for large kilns of 2.2E

- 05 lb/ton, 29 μ g/dscm and 2.7E

04 lb/hr and small kiln limits of 2.0E

- 04 lb/ton, 70 μg /dscm and 1.1E

- 04 lb/hr.

Commenter 0540 contended that the proposed rule Hg numerical limits based on a 3 pool floor for large kilns in particular are not representative of the best performing sources in the so urce category; the commenter recommended that the EPA take a fresh look at Hg UPL determinations using all available data.

Response 1 : The EPA disagrees with the commenter that it is a viable option to consider 12 percent of the industry when developing a MACT flo o r for Hg

. As was the case between proposal and final for the PM MACT floor development, the EPA asked for, but did not receive additional data to justify using 12 percent of the universe of kilns to develop a MACT floor. In addition, the EPA had t o remove several data points from the PM data base due to faulty emissions testing and thus further did not believe the entire dataset of best performing sources were on hand in order to develop a MACT floor based on 12 percent of the universe of kilns. Si nce EPA only had Hg data for limited kilns, there is no avenue to develop a MACT floor based on 12 percent of the universe of kilns. Thus, t he EPA is finalizing its proposed approach to use 12 percent of the data available to determine the number of kilns in the Hg MACT floor pools

. A s previously discussed above

, the EPA is also using 12 percent of data av ailable to determine the number of kilns in the PM MACT floor pools. However, as discussed in the MACT floor memo for the final rule, t he EPA has develope d a Hg raw material factor that has been incorporated in the Hg UPL calculations , which is based on data the EPA did receive between proposal and final

. Please see the MACT floor memo for the final rule for more information about the Hg raw material factor and the revised Hg MACT floors.

7.2 UPL

Comment 1: Commenter 0554 stated the EPA proposed to use the UPL to set floor standards, even after the D.C. Circuit remanded the EPA ’ s use of that method in NACWA . 734 F.3d at32 1139

- 45. The commenter stated the EPA ’ s use of the UPL in this rule is unlawful, arbitrary, and capricious for the following reasons.

Commenter 0554 stated the CAA s ection 1 12(d)(3) unambiguously requires floors to reflect the

“ average ” emission level achieved by the relevant best

- performing sources. The commenter stated by using the word “ average, ” Congress demanded a measure of ordinary, usual performance

-- a central tendency

-- of the “ emissions limitation achieved by the best performing 12 percent of the existing sources. ” See Webster ’ s S eventh New Collegiate Dictionary at 61 (1971) (defining “ average ” to mean “ equaling an arithmetic mean, ” “ approximating or resembling an arithmetic mean in being about midway between extremes, ” or “ not out of the ordinary ” ). See

, e.g. , Leocal v. Ashcroft

, 543 U.S. 1, 9 (2004) ( “ When interpreting a statute, we must give words their ‘ ordinary or natural ’ meaning. ” ) (quoting Smith v. United States , 508 U.S. 223, 228 (1993)).

Commenter 0554 stated in the EPA ’ s previous attempt to establish a rule for brick and clay ceramics sources, the EPA formally adopted an “ interpretation of average emission limitation ” acknowledging “ that it is a measure of central tendency, such as the arithmetic mean or the median. ” 68 FR 26700; see also 59 FR 29196, 29199 (Mar. 9, 1994) (formal rulemaking establishing that “ EPA construes the word ‘ average ’ in section 112(d)(3) to authorize the Agency to use any reasonable method, in a particular factual context, of determining the central tendency of a data set ” ). The commenter stated acc ording to the EPA, “ Congress spoke with clarity in [ s ection 1 12(d)(3)(A)] of the Clean Air Act, ” and that the section “ lends little support for an interpretation under which standards might be set at the emission limitation achieved by the worst performing member of the best performing 12 percent of existing sources, ” while the Act ’ s legislative history “ points strongly in the opposite direction ” from any such “ worst

- of

- the

- best ” construction. 59 FR 29199.

Commenter 0554 stated the EPA has consistently reaf firmed that interpretation in its rulemakings. E.g. , 68 FR 1276, 1286 (Jan. 9, 2003), (plywood); 67 FR 30848, 30853 (May 8, 2002) (semiconductors); 66 FR 58,610, 58,618 (Nov. 21, 2001) (asphalt processing); 64 FR 2611, 2612 (Jan. 15, 1999) (natural gas tra nsmission & storage); 61 FR 48208, 48210 (Sept. 12, 1996) (polymers & resins).

Commenter 0554 stated that CAA section 1 12(d)(3) also unambiguously requires that floors reflect the emission level actually “ achieved ” by the relevant best

- performing sources ( those with the lowest emission levels). Sierra Club , 479 F.3d at 880

- 81. The commenter stated the EPA may not override the floor requirements with its own notions about what is “ achievable. ” Id. at 877

- 79, 880

- 81; Cement Kiln Recycling Coalition v. EPA , 25 5 F.3d 855, 861 (D.C. Cir. 2001). The commenter stated speaking consistently in the past tense, Congress used the word

“ achieved ” four times in this provision. The commenter asserted that Congress meant what it said: “ section [1 12 ] (d)(3) requires floors based on the emission level actually achieved by the best performers. ” Sierra Club , 479 F.3d at 880

- 81.

Commenter 0554 stated to satisfy the CAA , therefore, existing source floors must reflect the average (i.e., a “ central tendency ” ) of the emission levels “ actually achieved ” by the relevant best

- performing sources. The commenter stated floors must be “‘ demonstrate[d] with substantial33 evidence

- not mere assertions ’

.... ” Ne. Md. Waste Disposal Auth. v. EPA , 358 F.3d 936, 954 (D.C. Cir. 2004) (quoting Cemen t Kiln , 255 F.3d at 866 and Sierra Club v. EPA , 167 F.3d 658, 662 (D.C. Cir. 1999)).

Commenter 0554 stated although CAA s ection 1 12(d)(3) unambiguously requires floors to reflect the “ average ” emission level actually “ achieved ” by the best performing 12 pe rcent of units, the EPA set floors at the upper prediction limit for the sources it claimed were the best performers.

Response 1: The EPA disagrees with the commenter. The NACWA court did not find the UPL to be an arbitrary approach, but simply asked for a better explanation from the Agency. The UPL memorandum in the docket for this rule provides the explanation of what the UPL represents sought by the NACWA Court. It also explains why the UPL is representative of the level of performance achieved by the be st performing unit or units. The court did not state that the

“ average emissions limitation achieved by the best performing 12 percent ” must be equal to the mean of the available data, as suggested by the commenter, and in past decisions the court has uphe ld that it is appropriate for EPA to account for variability when establishing numeric MACT standards. See Mossville Environmental Action Now v. EPA , 370 F.3d 1232, 1241

- 42 (D.C. Cir. 2004). Thus, t he EPA maintains the UPL approach to calculate the MACT floors for Brick tunnel kilns in the final rule . Please see the “ Use of the Upper Prediction Limit for Calculating MACT Floors ” memo (EPA

- HQ

- OAR

- 2013

- 0291

- 0128) found in the docket for this rule, for the EPA ’ s justification of the UPL approach.

Comment 2: Commenter 0554 stated as the EPA itself made clear, the upper prediction limit is the level that a best performing facility has one in 100 chance of exceeding. MACT Floor Memo

- Brick at 3; MACT Floor Memo

- Clay Ceramics at 3. The commenter stated in othe r words, it is a level that the EPA expects 99 out of 100 future compliance tests by any of the best performing facilities in the top 12 percent to “ fall below. ” 79 FR 75635. The “ UPL estimates what the upper bound of future values will be. ” MACT Floor Mem o

- Brick at 3; MACT Floor Memo

- Clay Ceramics at 3.

Commenter 0554 stated the EPA ’ s UPL is not an “ average ” or a measure of “ central tendency. ” The commenter stated it is, as its name indicates, an “ upper limit ”

-- the emission limitation that every memb er of the best

- performing 12 percent will “ fall below, ” virtually all of the time. 79 FR 75635; UPL Memo at 5 (describing UPL as “ a limit that can be met by all the existing sources in the floor at all times ” ). The commenter stated such a once

- in

- 100 emiss ion level is not a measure of “ average ” emissions any more than a hundred

- year flood can be a measure of

“ average ” water levels; thus, the EPA cannot support its claim that the UPL creates an estimate of the emission limitation “ achieved by the average sou rce. ” UPL Memo at 10. The commenter stated the EPA does not adequately explain how the UPL is an “ average. ”

Commenter 0554 stated given its ordinary meaning and the meaning the EPA itself has adopted through notice

- and

- comment rulemaking, “ the word ‘ averag e ’ in [ s ection 1 12(d)(3)], ” allows the EPA only to use a “ reasonable method ... of determining the central tendency of a data set. ” 59 FR 29199. The commenter stated a level that the EPA expects 99 out of 100 future tests by any source in the top 12 percen t to “ fall below ” is not a measure of the “ central tendency ” of the emission levels achieved by this group of sources; rather, it is a measure of one extreme, an34 “ upper bound ” on what any of those sources might emit in a future test. MACT Floor Memo

- Brick at 3; MACT Floor Memo

- Clay Ceramics at 3. The commenter stated the UPL does not, as the EPA claims, estimate an emission limitation “ achieved by the average source. ” 79 FR 75636. The commenter stated a floor that the EPA expects even the worst performing source within the top 12 percent to meet in 99 out of 100 future tests is not, in any sense, representative of “ average ” source in that group. See Natural Res. Def. Council v. Daley , 209 F.3d 747, 754 (D.C. Cir. 2000). The commenter stated the UPL does not aim for an “ average, ” it aims for an entirely different target: an “ upper limit ” that every source within the top 12 percent will meet at virtually all times.

Response 2: The EPA disagrees with the commenters that the UPL is not representative of the average emissions limitation achieved over time by the best performing sources or sources. T he CAA leaves to EPA ’ s discretion the manner in which to calculate “ the average emis sions limitation achieved ” by the best performing sources. The EPA has used the average of the lowest emission data from the top performing 12 percent of data available in calculating the MACT floors. The EPA has then incorporated variability in developing the final MACT floor limits in the final rule. The EPA has conducted traditional outlier analyses to remove from the data set any data determined to be statistical outlier data. The EPA believes that the data incorporated in the MACT floor pool represent the variability present at the various br ick and clay ceramics manufactures

.

As stated in the memorandum entitled “ Use of the Upper Prediction Limit for Calculating MACT Floors ” (Docket No. EPA

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- 0128) ( “ UPL memorandum ” ), in “ the context of development of MACT floors, the UPL is a value, calculated from a dataset, which identifies the average emissions level that a source or group of sources is meeting and would be expected to meet a specified percent of the time that the source is operating . That percent of time is based on the confidence level used in the UPL equation. For a single best controlled emission source that serves as the basis for a new source MACT floor, the 99 percent UPL is the emissions level that the source would be predicte d to be below during 99 out of 100 performance tests, including emissions tests conducted in the past, present, and future, based on the short term stack test data available for that source. It is important to note that the UPL does not represent the worst emissions performance of the best performing units at any time, but rather the average level expected to have been achieved over time, as the first element of the UPL equation is the average of the short

- term emissions test data from the best performing u nits.

In other words, the 99 percent UPL is the level of emissions that we are 99 percent confident is achieved by the average source represented in a dataset (in the case of MACT standards, the dataset representing the performance of the best performers as specified in the CAA) over a long

- term period based on its previous, measured performance history as reflected in short

- term stack test data. ”

Comment 3: Commenter 0554 stated the interpretation of the term “ average ” that the EPA advanced in this rulema king is internally inconsistent. The EPA “ interprets the average to mean the average emissions over time. ” UPL Memo at 3. The EPA also claimed that the UPL represents “ the average level expected to have been achieved over time ” by the relevant sources, id

. at 4, and represents a level of emissions the EPA does not expect the average source to exceed. Id . at 6. The EPA conceded the upper prediction limit is an “ upper limit ” on the relevant35 sources ’ emissions. Id . at 3. Yet the EPA also implied that the upper prediction limit may satisfy the Act by describing the “ average level ” achieved by the best performers over time, Id . at 4

- 5, and at others, the EPA suggests it satisfies the Act by describing the emission level constantly achieved by a single “ average so urce. ” Id . at 4, 10. The commenter stated claiming that the same statutory provision means different things “ diverges from any realistic meaning of the statute. ” Massachusetts v. Dep ’ t of Transportation , 93 F.3d 890, 893 (D.C. Cir. 1996). The commenter
sta ted it is also arbitrary. Dep ’ t of Treasury v. FLRA , 739 F.3d 13, 21 (D.C. Cir. 2014) ( “ set[ting] forth two inconsistent interpretations of the very same term ” is arbitrary and capricious).

Commenter 0554 stated the interpretation of the term “ average ” tha t the EPA advanced in this rulemaking is a departure from, and directly conflicts with, its own long

- standing interpretation of the Act, which it adopted through notice

- and

- comment rulemaking and reaffirmed many times. 59 FR 29199. The commenter stated alt hough the EPA previously rejected any understanding of the word “ average ” that would encompass an emission limitation “ achieved by all members of the best performing 12 percent, ” id . at 29,197, that is precisely the function of the UPL. The commenter state d the EPA does not acknowledge its prior interpretations, nor does it explain its reversals. See FCC v. Fox Television Stations , 556 U.S. 502, 515 (2009) (agencies may not “ depart from a prior policy sub silentio ” ); Mountain Commc ’ ns v. FCC , 355 F.3d 644, 648

- 49 (D.C. Cir. 2004) (action arbitrary where agency “ changed direction without explanation, indeed without even acknowledging the change ” ).

Response 3: The EPA interprets the average to mean the average emissions over time, based on both the calcu lated average of all emissions test data from the best performing source or sources and the available information regarding the variability of emissions. The UPL, which EPA uses to account for variability among the best performing sources, reflects an uppe r limit for the emissions of those sources at times other than when the emissions tests occurred. This not only is a prediction of the emissions performance of those sources in tests conducted in the future, but is also an indication of the range of curren t average emissions performance of those units.

Comment 4: Commenter 0554 stated the authorities on which the EPA seeks to rest its claim that the upper prediction is an average confirm that the upper prediction limit is not an average. See UPL Memo at 4 (citing Luko & Neubauer, Statistical Intervals Part 2: The Prediction Interval, Standardization News (October/Nov. 2011) (http://www.astm.org/standardization

news/datapoints/ statistical

- intervals

- part

- 2

- so11.html); Gibbons & Coleman, Statistical Methods f

or Detection and Quantification of Environmental Contamination (2001)). Luko and Neubauer state that the prediction limit is “ different ” from an “ interval for the mean with some degree of confidence. ” Luko & Neubauer at 1. Likewise, Gibbons and Coleman exp ressly note the difference between a prediction limit and a “ confidence interval for the mean. ” Gibbons & Coleman at 31. The commenter stated these sources further point out that prediction limits provide “ wider ” results

-- that is, higher upper limits

-- than an estimate of the mean, in part because they reflect “ the variability of future observations, ” rather than just the variability in

sources ’ actual performance. Id

. Commenter 0554 stated the EPA claimed that its upper prediction represents an average over time because “ the first element of the UPL equation is the average of the short

- term emissions test data from the best performing units. ” UPL Memo at 4. The commente r stated the mere fact that the first element of the equation is an average does not demonstrate that the final product of36 the equation is the average over time. The EPA provided no basis on which it could reasonably conclude that just because its upper pr ediction equation starts with an average and then adds a number to “ address variability, ” this equation yields the average over time.

Commenter 0554 stated the EPA also argued that because the average is in the first half of the equation, the UPL “ goes up or down ” with average emissions. Id . at 11. The EPA also admitted, however, that the upper prediction also goes up or down with factors that are entirely unrelated to the average: “ the number of runs in the dataset ” and “ the number of runs averaged for eac h emissions test. ” Id .; see also NACWA , 734 F.3d at 1144

- 45. The commenter stated that the record shows that the number of runs in a dataset can make the EPA ’ s upper prediction go up (i.e., get worse) even when the average emissions achieved go down (i.e., get better). See NACWA , 734 F.3d at 1144.

Response 4: As discussed above, the NACWA court did not state that the “ average emissions limitation achieved by the best performing 12 percent ” must be equal to the mean of the available data, as suggested by the commenter, and in past decisions the court has upheld that it is appropriate for EPA to account for variability when establishing numeric MACT standards. See Mossville Environmental Action Now v. EPA , 370 F.3d 1232, 1241

- 42 (D.C. Cir. 2004). Also the CAA leaves to EPA ’ s discretion the manner in which to calculate “ the average emissions limitation achieved ” by the best performing sources.

Comment 5: Commenter 0554 stated the EPA claimed that an emissions test dataset from another rulemaking de monstrates that the UPL for that dataset “ represents the average emission level achieved by the best performing sources. ” UPL Memo at 12

- 15. The commenter stated that EPA conceded, however, “ no source among the best performing 12 percent had an overall

ave rage above the 99 percent UPL, ” and only the worst performing source in the top 12 percent had even one “ 3

- run test average above the UPL. ” Id . at 14. The commenter asserted that to argue that just because one test result is higher than the UPL that the UP L is an “ average ” is like arguing that because a river will sometimes reach its 100

- year flood level, the 100

- year flood level is an “ average ” height for the river. The commenter stated that four units had “ one test run value ” above the EPA ’ s upper predict ion, id ., is irrelevant. The commenter stated according to the EPA, the UPL produces an estimate of a 3

- run test average, not a single “ test run. ” Id . The commenter asked if, as the EPA asserts, the UPL predicts the emission limitation consistently achieve d by the “ average source ” among the best performers, id . at 4, 10, or (as the EPA also, and contradictorily, contends) the “ average emissions limitation ” achieved by the best performing units

- why do all the best performers fall below it, virtually all of the time.
Response 5: The Case B example from the UPL Memo is an example from sewage sludge incinerators, where there are 150 existing units in the multiple hearth subcategory nationwide with 18 sources in the MACT floor pool. In general, the closer each individual unit ’ s average is to the overall MACT floor pool average, the greater the likelihood that the unit will be able to meet the calculated UPL MACT floor. In the Case B example provided by EPA in the UPL Memo located in the docket for this rule , 13 out of 18 sources had a unit average that was less than the average of the overall MACT floor pool. For the other 5 units of the 18 their average was above the overall MACT floor pool, thus their ability to meet or not meet the calculated UPL depends on the quantity of the variability component of the UPL equation being added to the average component of the UPL equation . The variance component of the UPL equation is37 dependent on the variabili ty of the test runs from the entire MACT floor pool. In the Case B example provided by the EPA in the UPL Memo the variance component added enough variability that all of the 18 units of the MACT floor pool could meet the calculated UPL. That is not always the case for every UPL calculation , adding the variance component to the average component in the UPL equation does not always result in “ all the best performers falling below the calculated UPL. ” For MACT floor pools that contain sources with little vari ability between all the runs resulting in a low variability component , the likelihood of all the sources in the pool being able to meet the calculated UPL decreases. For MACT floor pools that contain sources with a great amount of variability between all t he runs resulting in a high variability component

, the likelihood of all the sources in the pool being able to meet the calculated UPL increases.

Comment 6: Commenter 0554 stated by setting floors at the upper prediction limit, the EPA also
contravenes CAA section 1 12(d)(3) ’ s unambiguous requirement that floors reflect what the best

sources “ actually achieved. ” Sierra Club , 479 F.3d at 880

- 81. The commenter stated the statute unambiguously requires floors to reflect what the best performing sources “ achieve d, ” not what EPA predicts they will achieve in the future. S ee Sierra Club , 479 F.3d at 880

- 81. The commenter stated the UPL is not a measure of the performance of the source but a prediction value and does not represent the current sources; the UPL does n ot merely address the variability in the emission levels that sources actually “ achieved ” ; rather, it further inflates the floors to ensure that they will be higher than the level the EPA is 99 percent confident no source in the top 12 percent will exceed in a hypothetical “ future ” compliance test. The commenter stated by requiring floors to reflect what the relevant best sources actually “ achieved, ” however, the text of CAA section 1 12(d)(3) eliminates any discretion to set floors at levels EPA expects the relevant sources not to exceed in “ future ” compliance tests. The commenter stated for the new source floors, the UPL does not reflect what any source actually “ achieved, ” but rather is a value that the EPA expects the best controlled source to always fall below; the UPL approach is contrary to the CAA ’ s plain meaning.

Commenter 0554 stated Congress enacted section 1 12(d)(3) to put an objective constraint on the EPA ’ s discretion. New Jersey v. EPA , 517 F.3d 574, 578 (D.C. Cir. 2008). The commenter stated by substituting its subjective upper

- limit

- prediction for an objective measure of what sources have “ actually achieved, ” Sierra Club , 479 F.3d at 880

- 81, the EPA impermissibly “ nullifies [a] textually applicable provision[] meant to limit its discretion. ” Whitman v. Am. Trucking Ass ’ ns , 531 U.S. 457, 485 (2001).

Commenter 0554 stated to promulgate a non

- arbitrary rule, “ EPA ‘ must demonstrate with substantial evidence

- not mere assertions ’” that its floors satisfy the statute. NACWA , 734 F.3d at 1131. The c ommenter stated nowhere in the record has the EPA demonstrated that its UPL is an accurate estimate of the “ average ” emission level that the relevant best sources have actually

“ achieved, ” or that it reflects what the best controlled source “ achieved in pr actice. ” The commenter stated the UPL is neither the average emission level achieved by the best performing sources nor the emission level achieved by an average source; rather, it is a level the EPA expects sources in the top 12 percent

-- including the w orst

-- to fall below in any future test, and the best controlled source to always fall below.

Commenter 0554 stated even if the EPA could base floors on what it thinks the best

- performing sources will achieve in the future rather than what they actually a chieved in the past

-- which it38 cannot for the reasons given above

-- the EPA ’ s formula assumes that sources ’ future will vary randomly. The commenter stated that sources ’ performance is not random but, rather, is constrained by the steps that different op erators take to control their emissions, including fuels they choose to burn, controls they install, and the care with which they operate those controls. Sierra Club , 479 F.3d at 880

- 83; 67 FR 47907. The commenter stated the assumption that all variability is inherent variability over which operators have no control is unsupported and inaccurate; counting the effects of these factors as inherent variability results in floors that do not reflect the best source or sources ’ actual performance. The commenter s tated the EPA does not provide any explanation for its apparent assumption that sources ’ actual emission levels will vary to the full extent of the 99th percent UPL.

Response 6: The E PA disagrees with the commenter ’ s statement that the UPL does not reflec t emission levels “ a ctually a chieved. ” The commenter misunderstands the purpose of the UPL calculation. It is not intended to only predict the best performing sources ’ future performance, although it can be used to do that. Rather, for the purpose of setti ng MACT standards, it is used to estimate the best performing sources ’ current emissions over time, rather than during the very short

- term periods measured during stack testing.
The EPA interprets “ emissions performance, ” a s used in section 112(d)(3) to me an the emissions of a source over the long term, rather than just during a short

- term stack test. This is a reasonable interpretation of the statutory directive that the MACT s t andard be no less stringent than the average emissions limitation “ achieved by ” the best performing sources, since the emissions level of a source is not expected to always be the same as it is during stack testing. The EPA thus uses the UPL to assess the emissions achieved and achievable, for a prescribed confidence level, by the so urce based on its tested performance at times other than when stack testing was conducted. This enables EPA to calculate the average emissions performance of the best performing sources over time. The EPA uses the UPL approach in its MACT floor analysis be cause it incorporates the average performance of the best performing sources and the variability of the performance during testing conditions. The commenter is incorrect that the UPL calculation results in an emissions level that the worst source in the to p 12 percent of sources will fall below. As explained in the “ Use of the Upper Prediction Limit for Calculating MACT Floors ” memo (EPA

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average emissions level of the best performing sources, and t hen applies a second step in order to account for the variability in emissions performance of those sources. For the development of the Hg floor, the variability of the raw material was also taken into account. The UPL represents the value which one can ex pect the mean of a specified number of future observations to fall below for a specified level of confidence based upon the results of an independent sample from the same population

. Please see the “ Use of the Upper Prediction Limit for Calculating MACT Fl oors ” memo (EPA

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- 0128) for the EPA ’ s justification of the UPL approach.
The EPA disagrees with the commenter regarding randomness of emissions from sources imposed by use of the UPL formula. Use of that formula provides a way to restrict t he effect of randomness to a known range of values calculated from short term testing, as opposed to the
commenter ’ s notion that the effect of randomness is varied and unknown. Of course, similar operation of the source, consistent with the conditions unde r which it was tested, is a necessary component of the UPL calculations; otherwise, the randomness to which the commenter refers39 could creep in. As the emission limits are established on a certain set of practices and operations associated with a successfu l performance test of the best

- operating source, those good practices and operations are contained in the values calculated by the UPL and should also serve to reduce the randomness of which the commenter expresses concern.

Comment 7: Commenter 0554 stated the UPL is a particularly inaccurate representation of what the best source or sources “ actually achieved ” where the emissions dataset is small; as the D.C. Circuit has recognized, the results generated by the EPA ’ s upper prediction approach depend heavil y “ on the size of the dataset. ” NACWA , 734 F.3d at 1144

- 45. The commenter stated a smaller dataset causes the EPA ’ s statistical approach to generate higher (i.e., weaker) floors. Id

. The commenter stated in this record, the EPA “ recognize[s] that the use o f the UPL ” for small datasets introduces “ uncertainty ” in the calculation of MACT standards. EPA, Approach for Applying the Upper Prediction Limit to Limited Datasets at 2 (Sept. 17, 2014), Docket Item No. EPA

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- Brick ” ). The commenter stated the “ number of values in a particular dataset[] is an important component of the UPL approach, ” Id . at 1; the t

- score (or z

- score, depending on which equation is used) is used by the EPA to estimate the uncertain ty and variability for a certain confidence level, and “ is highly variable at the smallest sample sizes ” and “ can have a disproportionate effect, overwhelming the other components ” of the UPL calculation. Id . at 2. The commenter stated moreover, the sample size itself is a separate variable in the EPA ’ s UPL equation, and as the sample size gets smaller, the UPL gets larger (all other variables being constant). Id . at 4. The sample size is a “ key component ” in the calculation of two other variables in the EP A ’ s UPL equation: the mean and variance; “ larger sample sizes provide better estimates of the population mean and variance. ” Id . The commenter stated also, the confidence level chosen by the EPA influences the t

- score (or z

- score), which in turn is “ highly variable ” where there is limited data. Id

. Commenter 0554 stated in light of the significant and pervasive uncertainty that small sample sizes introduce into the UPL calculation, the UPL cannot represent the performance that the best

sources “ actually ach ieved, ” as the Act requires, where sample sizes are small; and the EPA is frequently faced with the task of establishing floors where it has limited data. The commenter stated for example, in these rules alone, the EPA identified 20 floors for which the EP A had fewer than 7 data points. See id . at 8; EPA, Approach for Applying the Upper Prediction Limit to Limited Datasets at 8 (Sept. 17, 2014), Docket Item No. EPA

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- 0218 (hereinafter “ Limited Datasets Memo

- Clay Ceramics ” ). The commenter st ated the serious shortcomings in the UPL for small datasets alone highlights the need to abandon the UPL approach.

Commenter 0554 stated the EPA recognizes that the UPL generates higher and potentially inaccurate and unrepresentative floors where the sampl e size is smaller; yet to address this fundamental problem with the UPL approach, EPA proposes that for sample sizes of fewer than 7, it will “ further evaluate ” the data in “ one or more ” ways “ on a case

- by

- case basis ” to check to see if “ the uncertainty as sociated with a limited dataset does not cause the calculated emission limit to be so high ” as to be illegal. Limited Datasets Memo

- Brick at 6. The commenter stated the EPA offers few details as to how, exactly, it will know when the small sample size ca uses the UPL to be unacceptably “ high, ” except that the EPA will use its “ experience ” and “ technical40 expertise ” in its evaluation. Id . at 6

- 7. The EPA specifies no standards to guide this ad hoc evaluation.

Commenter 0554 stated the EPA ’ s proposed solution to the significant flaw in the UPL identified by the D.C. Circuit provides no assurance that the UPL will produce accurate limits. The commenter stated the EPA is asking that it be trusted to take a second look at an admittedly flawed formula and make sur e it is “ reasonable. ” Id . at 7 ( “ we ... would ensure that the emission limit is reasonable ” ); id . at 6 ( “ The evaluation will include one or more of the following ...: confirming that the data distribution was selected correctly ” and “ ensuring that we use t he most appropriate UPL equation. ” ). The commenter stated the reasonableness is not the legal standard: the EPA must demonstrate with “ substantial evidence ” that use of the UPL for small datasets represents what the best source or sources “ actually achieved. ” The commenter stated the EPA needs to do more than double

- check its math to make such a showing where the standard

- setting method being applied is undisputedly defective.

Commenter 0554 stated the EPA ’ s application of its approach to evaluating and addressing UPL

based floors derived from limited data shows how insufficient this evaluation is; of the twenty floors based on small datasets, the EPA concludes without much reasoning that no adjustments were warranted.

Commenter 0554 stated also, the EPA fails to rationally explain why sample sizes smaller than 7 require further evaluation, but slightly larger sample sizes do not. The commenter stated the EPA ’ s own data demonstrates that uncertainty continues to decrease beyond 6 samples as the sample size increases. Id . at 3, 5

- 6 (showing a “ 7% reduction from 6 to 7 samples ” and a “ 5% reduction from 7 to 8 ” samples). The commenter stated the EPA fails to point to any statistical reason why the uncertainty caused by sample sizes greater than 6 can be ig nored; it is irrelevant that the test data itself may have some uncertainty, as the EPA points out: uncertainty elsewhere in the standard

- setting process does not justify use of a method to account for variability that adds even more uncertainty to the out come. The commenter stated if anything, additional uncertainty caused by the EPA ’ s proposal to use a UPL is less justifiable if it compounds existing concerns about accuracy.

Response 7: As discu ssed above, t he E PA disagrees with the commenter ’ s statement that the UPL does not reflect emission levels “ a ctually achieved ,” including the UPL fo r limited datasets. A limited dataset does not automatically mean that the calculated UPL is flawed and should not be used; however , given the potential impact of uncert ainty due solely to the n umber of samples, it is appropriate for the EPA to assess all factors used in the UP L calculations when determining an emissions limit, so that the emissions limit reflects the average performance of the units upon which the limit is based. The basis for the 6 sample cut off for limited datasets was determined based on the effect of the sample siz e dependent component of the UPL equation, the t

- statistic

. As the Limited Dataset Figure 1 and Table 1 demonstrate, the t

- statistic for sample sizes below 7 have a greater value and thus a greater contribution to the UPL equation. The t

- statistic for sample sizes at and above 7 start to level o ff and have a lesser contribution to the UPL equation. As such, the limited dataset cutoff was de termined to be below 7 samples.41 Please see the “ Approach for Applying the Upper Prediction Limit to Limited Datasets ” memo (EPA

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- 0127) for more information regarding the UPL approach for limited datasets

.

Comment 8: Commenter 0554 stated the EPA ’ s specific selection of the 99 percent UPL as opposed to a 95 percent UPL, a 90 percent UPL, or some other UPL is not adequately explained. The commenter stated the EPA merely states in conclusory fashion that the 99 percent level provides “ reasona ble assurance that the limit can be met all times ” by a best performing source, without any analysis or explanation of why a different level of confidence would not provide such “ reasonable assurance. ” UPL Memo at 10. The commenter stated the EPA fails to reconcile its choice of a confidence level that “ can be met all times ” with the statutory language, which requires that EPA use an “ average; ” thus, the EPA ’ s choice of this particular UPL, which then determines the outcome of its floor analysis, is arbitra ry. The commenter stated the EPA ’ s reason for deciding not to be more conservative in standard setting for air toxics with significant adverse public health effects should be adequately justified in the record; and yet, it is not.
Response 8: While the UPL can be calculated at different confidence levels, the EPA selected the 99 percent level in order to provide reasonable assurance that the limit can be met at all times by a source with emissions at the average level achieved by the best performing source or

sources

. 5

In the context of development of MACT floors, the UPL is a value, calculated from a dataset

, wh ich identifies the average emissions level that a source or group of sources is meeting and would be expected to meet a specified percent of the time that the source is operating. That percent of time is based on the confidence level used in the UPL equati on, as explained in more detail below. For a single best controlled emission source that serves as the basis for a new source MACT floor, the 99 percent UPL is the emissions level that the source would be predicted to be below during 99 out of 100 performa nce tests, including emissions tests conducted in the past, present, and future, based on the short term stack test data available for that source. It is important to note that the UPL does not represent the worst emissions performance of the best performi ng units at any time, but rather the average level expected to have been achieved over time, as the first element of the UPL equation is the average of the short

- term emissions test data from the best performing units. In other words, the 99 percent UPL is the level of emissions that we are 99 percent confident is achieved by the average source represented in a dataset over a long

- term period based on its previous, measured performance history as reflected in short term stack test data.

Comment 9: Commenter 0540 supports the EPA ’ s consideration of equivalent compliance methods for Hg and total non

- Hg metals; however, in developing the equivalent standards, the EPA relied on oxygen content data that may be difficult to replicate. The commenter stated for 19 o f 27 sources in the non

- Hg floor and 2 of the 4 sources in the combined subcategories for Hg, oxygen content was obtained using Method 3 (Gas Analysis for the Determination of Dry

5 Telander, J. Use of the Upper Prediction Limit for Calculating MACT Floors . Memorandum from Jeff Telander to Docket ID No. EPA

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- 0128.42 Molecular Weight). 6 The commenter stated the field reliability of the Orsat Analyzer used in Method 3 has been documented by the EPA to potentially introduce sizeable errors in the correction of particulate catches to reference conditions. 7 The commenter stated the results of the EPA ’ s study further concluded that the operator cri terion in Method 3 does not ensure that accurate results will be obtained. The commenter recommended that the equivalent standards be adjusted to UPL with 99.9 percent or 99.99 percent confidence interval to account for the uncertainty of the Method 3 oxyg en content data; this approach will reasonably ensure that the equivalent emission limit selected as the MACT floor adequately represents the level of emission actually achieved by the average of the units in the top 12 percent

. Response 9: Without being a ble to evaluate and quantify how “ uncertain ” the Method 3 measurements were, the EPA is not adjusting the confidence interval used in the UPL equation for the alternate concentration limits based on oxygen corrected data . However, the EPA has revised the e quivalent concentration based limits to be developed from 17 percent oxygen corrected concentrated data. The EPA asserts that correcting at 17 percent rather than 7 percent as proposed, with provide more representative values of kilns ’ operating conditions

. The EPA is retaining the 99 percent confidence interval in all UPL calculations.

Comment 10: Commenter 0540 support ed the EPA ’ s use of discretion to account for variability in setting the Hg standard, but recommends that if numerical emission limits are set for Hg, that they be revised to reflect the variability of the Hg in the mined material for the sources in the floor. The commenter stated just as the EPA determined the need to adjust the emission limits in the Boiler MACT to account for the variability of Hg in the fuel, so should the EPA consider the variability of Hg in the raw materials used to manufacture brick.

According to Commenter 0540

, in the preamble to the proposed Boiler MACT, the EPA stated:

However, after review of the available HAP data, including both emission test data and fuel analyses, we determined that it was inappropriate to use only the MACT floor approach to determine variability and to establish emission limits for boilers and process heaters, because this approach considers only the emissions test data. The main problem with using only the HAP emissions test data is that the data, which may reflect the variability of fuel

- related HAP of the best performing units, m ay not reflect the variability of fuel

- related HAP from the best performing units over the long term.

Commenter 0540 stated this logic is applicable to brick kilns not only with regard to the long

term variability of fuel Hg content, but to the variability of Hg in the clay and shale within a mine and between mines. The commenter stated subsequent to the stack testing performed in response to the EPA ’ s ICR, the brick industry began a raw material testing program to gather data to better understand the Hg le vels in the clay; while the average raw material data results in emission estimates that are in general alignment with Method 29 stack test results, the range of Hg raw material content for some facilities suggest that the variability within a mine could b e

6 Of the three sources in the Hg floor for large kilns, one used Method 3, one used Method 3A, and one is unknown. Attachment to Test Data Used in BSCP Proposed Rule , November 6, 2014. Docket Item No. EPA

- HQ

- OAR

- 2013

- 0291

- 0121.

7 William J. Mitchell & M. Rodney Midgett (1976) Field Reliability of the Orsat Analyzer, Journal of the Air Pollution Control Association, 26:5, 491

- 495, DOI 10.1080/00022470.1976.1047027643 considerable. The commenter stated for example, one facility has raw material data that ranges from 23 to 114 parts per billion ( ppb ) ; using a mass balance approach, emissions from a kiln at this facility are estimated to range from 2.5E

- 5 lb/ton to 1.2E

- 4 lb/ton. The commenter stated the UPL calculations based on this kiln clearly would be based on a single short term assessment of emissions (i.e., 3 one hour tests) and by default a short term, single assessment of the Hg content in the clay. The comment er stated as the EPA noted in the Boiler MACT preamble, the variability over the long term may not be adequately reflected in a UPL calculation based on a stack test alone. The commenter recommends that the EPA include the variability in the raw material i n setting the Hg numerical limits by adjusting the stack test based UPL by a raw material variability factor and/or by adjusting the test results prior to the UPL determination by an average raw material variability factor.

Commenter 0558 stated a stack te st for one of their company ’ s kiln was used to set the Hg limit for small kilns, however the very plant that was tested may have difficulty meeting the limit that was established as a result. The commenter stated their raw material contains varying amounts of Hg, especially between shale and fireclay; lab tests have shown that fireclay contains more Hg than shale. The commenter stated during the stack test that ultimately helped establish the limit, there was approximately 77 percent fireclay and 23 percent shale in the brick. The commenter asserted that had this test been performed with 100 percent fireclay, there is the strong possibility that the Hg result would have been higher, which may have ultimately resulted in a higher limit set by the EPA. The com menter also noted that there may be a wide variation of Hg even within fireclay itself, so setting a limit based on one stack test with 77 percent fireclay does not seem prudent unless the EPA also accounts for the variability of the raw material. The comm enter stated if EPA wants their assumption that no small kilns require Hg control to be valid, significant adjustments must be made to this floor calculation.

Response 1 0 : The EPA has received Hg raw material data during the comment period. The EPA has eva luated the data and developed a raw material variability factor that has been incorporated into the variability of the MACT floor pool data for each Hg MACT floor UPL equation. Please see the MACT floor memo for the final rule for more information.

7.3 Em ission Limit
7.3.1 Manipulation of Data for MACT Floor

Comment 1: Commenter 0543 stated the EPA identified a number of issues with stack test reports, often discarding a test run and evaluating only two runs for a facility; these tests were discarded for p roblems like sample contamination, manganese contamination, filter failure, and other failures that were not identifiable during the tests. The commenter stated some of these issues are due to the tested values being so close to method and analytical detec tion limits.
Response 1: The E PA agrees there were issues with stack reports ; however , the EPA disagrees that some of these issues were due to tested values being so close to method and analytical detection limits. No reports were discarded due to tested values being close t o method and analytical detection limits. The stack test reports list the filter temperatures in the field data collected during stack test. BIA identified several tests where the filter temperatures were below the required temperature for certain stack tests. Th e PM test reports were reviewed

, and test runs outside the required tem perature for the filter were excluded in the floor calculations. Manganese44 ( Mn ) contamination was identified by a simple calculation of the ratio of the back half Mn mass to the front half Mn mass. If the ratio was over 5, that test run was assumed to have Mn contamination

, and were excluded

. Comment 2 : Commenters 0543 and 0547 stated data from synthetic area sources should not have been used in MACT floor cal culations.

Commenter 0543 asserted that the EPA can only consider kilns within the source category when establishing the MACT floor for each category or subcategory. The commenter stated the EPA incorrectly equates the terms “ source category ” and “ industry ” throughout this proposal; they are not the same, as the industry includes area sources (both “ true ” and “ synthetic ” ), as well as the major sources in the regulated source category. The commenter stated the EPA is permitted to consider the area sources on ly when evaluating options “ above the floor, ” but not for establishing the MACT floor. The commenter asserted that the EPA is unlawfully ignoring the phrase “ in the category or subcategory ” that is included in the CAA Section 112(d)(3)(A) because of an inc orrect belief that it would be “ unreasonable ” to ignore the best controlled sources in the industry. The commenter asserted that since the MACT floor precludes the consideration of costs that it is unreasonable to arbitrarily ignore key phrases within the CAA with respect to how the “ floor ” is established.

Commenter 0547 stated the proposed rule applies only to brick manufacturing operations located at a major source of HAP

. See

, e.g. , 79 FR 75673 (proposed section 63.8385

- “ You are subject to this subpart if you own or operate a BSCP manufacturing facility that is, is located at, or is part of, a major source of HAP emissions .... “ ). The commenter stated in other words, the rule applies to a major source category and is not applicable to non

- major sources , which do not belong to the source category. Yet the EPA relied on emissions data from a class of non

- major

sources

-- the so

- called “ synthetic area sources ”

-- in determining existing source MACT floors and the corresponding MACT standards. 8 The commente r stated relying on emissions data from sources that do not belong to the source category being regulated violates the unambiguous requirements of section 112(d); to correct this problem, EPA must recalculate the existing source standards using emissions d ata only from major source brick manufacturing plants.

Commenter 0547 stated CAA section 112(d)(3)(A) and (B) are the provisions that describe how EPA is required to determine the MACT floor for existing sources. These provisions state the following:

Emission standards promulgated under this subsection for existing sources in a category or subcategory may be less stringent than standards for new sources in the same category or subcategory but shall not be less stringent, and may be more stringent than

- (A) the average emission limitation achieved by the best performing 12 percent of the existing sources (for which the Administrator has emission information) ... in the category or subcategory for categories and subcategories with 30 or more sources, or (B) the average

8 See

, e.g. , 79 FR 75635 (“As of January 1, 2014, there were 225 operating BSCP tunnel kilns in the industry (including kilns at major sources and synthetic area sources); the top 12 percent of the kilns in the industry would be represented by the 27 best performing kilns . Therefore, we ranked the kilns with a FF

- based APCD in terms of lb/ton (as described in section IV.E of this preamble) and identified the 27 best performing sources from that group.”).45 emission limitation achieved by the best performing 5 sources (for which the Administrator has or could reasonably obtain emissions information) in the category or subcategory for categories or subcategories with fewer than 30 sources.

Comm enter 0547 stated these provisions plainly state the EPA ’ s obligations; the Agency must base the existing source MACT floor for source categories or subcategories containing 30 or more sources on emissions information from the best performing 12 percent of existing sources

“ in the category or subcategory. ” The commenter stated similarly, the EPA must base the existing source MACT floor for source categories or subcategories containing fewer than 30 sources on emissions information from the 5 best performing sources “ in the category or subcategory. ” The commenter stated in other words, for both large and small categories or subcategories, the existing source MACT floor must be based on emissions information from the better performing sources “ in the category or subcategory. ” The commenter stated this language is not ambiguous and cannot be construed to mean that the EPA may use emissions information from sources outside the given category or subcategory.

Commenter 0547 stated the U.S. Supreme Court has establi shed clear rules to guide administrative agencies in construing the statutes they implement; in Chevron USA. v. NRDC

, 467 U.S. 837 (1984), the court explained that “ [i]f the intent of Congress is clear, that is the end of the matter; for the court, as well as the agency, must give effect to the unambiguously expressed intent of Congress. ” Id . at 842

- 43. 9 The commenter stated under this so

- called

“ Chevron I ” analysis, because EPA is unambiguously directed to use emissions information from

sources “ in the cat egory or subcategory ” being regulated, the Agency has no choice but to follow this command.

Commenter 0547 stated the current proposal does not include any explanation as to why the EPA thinks it has authority to consider emissions data from synthetic area sources in setting existing source standards for facilities belonging to the major source category. The commenter stated in the 2003 BSCP rulemaking, however, an explanation was provided; the EPA reasoned that, in the section 112(a)(l) definition of “ majo r source, ” “ the reference to a source ’ s potential to emit considering controls allows the interpretation that a source ’ s potential to emit before and after controls is relevant, such that synthetic area sources may be considered within the meaning of this definition and included in MACT floor determinations for categories of major sources. ” 68 FR 26698.

Commenter 0547 stated this is an irrational interpretation of the definition of “ major source ” and, as such, it provides no support for the EPA ’ s position. The commenter stated under this interpretation, a synthetic area source actually would meet the definition of “ major source ” and, thus, should be regulated as a major source under applicable MACT standards; yet, the EPA has not sought to regula te synthetic area sources under this rule or any major source MACT standard issued to date. 10 The commenter stated if a “ synthetic minor ” area source is not a major source

9 The court goes on to explain that, if the statute is ambiguous, the n courts should defer to any reasonable interpretation adopted by the implementing agency

- the so

- called “Chevron II” analysis.

10 See

, e.g. , 79 FR 75665 (“There are no major sources producing ceramic tile. The five facilities that were major sources at the time of the 2008 and 2010 EPA surveys have already taken the necessary steps to become synthetic46 for purposes of applying a potentially applicable MACT standard for major sources, th ere is no rational basis for asserting that emissions data from the same source can be used in determining the existing source MACT floor for the major source standard.

Commenter 0547 stated alternatively, although the EPA has not advanced such an argument , the only way that the EPA could use emissions information from area sources in setting existing source MACT floors in the BSCP rule would be to include area sources within the source category and to regulate major and area sources together under a single standard. The commenter stated but, this approach is not plausible because it too would run afoul of unambiguous CAA requirements; Section 112(c)(3) provides authority for the EPA to list “ each category or subcategory of area sources which the Administrat or finds presents a threat of adverse effects to human health or the environment ... warranting regulation under this section. ” 11 The commenter stated this provision unambiguously authorizes the EPA only to list “ categor[ies] or subcatego[ies] of area sourc es ” based on findings specific to the given categories or subcategories. Id . (emphasis added). The commenter stated this language cannot be construed as meaning that an area source category or subcategory for which the requisite finding is made can somehow be extended such that it also include major sources or otherwise merged with a major source category. The commenter stated a “ category or subcategory of area sources ” must include only area sources

- plain and simple; in any event, there no longer is an ar ea source category for brick plants.

Commenter 0547 stated this is consistent with the BSCP area source listing notice, which unambiguously characterized the source category as a new “ area source category. ” See 67 FR 70428 ( “ The additional area source cate gories being listed pursuant to section 112(c)(3) and 112(k)(3)(B)(ii) are ... Brick and Structural Clay Products Manufacturing. ” ). The commenter stated thus, the statute requires an area source category for a given sector to be listed separately from a ma jor source category for the same sector; the EPA is without authority to take any other approach.
Response 2 : The EPA is continuing to use data from synthetic area sources (synthetic minor sources) in the rankings of sources and if applicable MACT floor ca lculations

. Section 112(d) of the CAA directs us to establish emission standards for each category or subcategory of major sources and minor sources of HAP listed for regulation pursuant to section 112(c) of the CAA. Each such standard must reflect a minim um level of control known as the MACT floor. (See CAA section 112(d).) However, section 112 of the CAA does not specifically address synthetic minor or synthetic area sources, which include those sources that emit fewer than 10 tons per year (tpy) of any H AP or fewer than 25 tpy of any combination of HAP because

area sources. Consequently, none of the known tile facilities will be subject to the provisions of the Clay Ceramics manufacturing rule...”). Also note that t his assessment does not take into account EPA’s “once in, always in” policy, where EPA asserts that once a major source is subject to substantive requirements under a major source MACT standard, that source cannot subsequently avoid the applicability of th e standard by becoming an area source. The commenter asserted that policy also is legally flawed and, thus, has no bearing on these arguments.

11 This was the authority EPA cited in listing BSCP as an area source category in 2002. See 67 FR 70427 (Nov. 22, 2002). EPA also cited section 112(k)(3)(B)(ii) as authority for the listing, but that provision is limited to “source categories or subcategories ... that are or will be listed pursuant to subsection (c).” So, section 112(k) provides no additional authorit y to list area source categories.47 they use some emission control device(s), pollution prevention techniques or other measures (collectively referred to as controls in this preamble) adopted under Federal or State regulations. If not for the enforceable controls they have implemented, synthetic minor sources would be major sources under section 112 of the CAA.

We believe that the appropriate interpretation of the CAA ’ s language and legislative history is that synthetic minor sources b e included in MACT floor determinations. First, the statute makes clear that our MACT floor determinations are to reflect the best sources in a category. For new sources in a category or subcategory, the MACT floor shall not be less stringent than the emis sion control that is achieved in practice by the best

- controlled similar source, as determined by EPA. (See CAA section 112(d)(3), emphasis added.) For existing sources in a category or subcategory with 30 or more sources, the MACT floor may be less string ent than the floor for new sources in the same category or subcategory but shall not be less stringent than the average emission limitation achieved by the best performing 12 percent of the existing sources (for which the Administrator has emissions information). (See CAA section 112(d)(3)(A), emphasis added. 12 ) Thus, section 112(d)(3) of the CAA requires that MACT floors reflect what the best

controlled new sources and the best

- performing existing sources achieve in practice. These phrases contain no exemptions and are not limited by references to sources with or without controls. Therefore, they suggest that all of the best

- controlled or best

- performing sources should be considered in MACT floor determinations, regardless of whether or not such source s rely upon controls.

Furthermore, section 112(d)(3) of the CAA expressly excludes certain sources that meet LAER requirements from MACT floor determinations for existing sources. (See CAA section 112(d)(3)(A).) The fact that Congress expressly excluded su ch LAER sources but did not also exclude synthetic minor sources suggests that no exclusion was intended for synthetic minor

sources.

Indeed, nothing in the statute suggests that EPA should exclude a control technology from its consideration of the MACT fl oor because the technology is so effective that it reduces source emissions such that the source qualifies as a synthetic area source . (See 67 FR 36460 and 36 464, May 23, 2002, stating this rationale for including synthetic minor sources in the floor deter mination for the proposed NESHAP for municipal solid waste landfills.)

Some commenters argue that because the BSCP source category only includes major sources and synthetic minor sources are not covered by the major source standard , synthetic minor source s (like true area sources) fall outside the regulated source category and should not be considered in MACT floor determinations. EPA agrees that the BSCP source category includes only major sources. (See 79 FR 75622 and 75626

, December 18, 2014 .) However, EPA disagrees that the CAA contemplates that synthetic minor sources must be treated like true area sources and

12 If a category or subcategory has fewer than 30 sources, the floor shall be ‘‘ the average emission limitation achieved by the best performing 5 sources (for which the Administrator has or could reasonably obtain emissions information) in the category or subcategory. ” (See CAA section 112(d)(3)(B), emphasis added.)48 excluded from MACT floor determinations. Section 112(a) of the CAA defines a major source

as:

any stationary source or group of stationary sour ces located within a contiguous area and under common control that emits or has the potential to emit considering controls, in the aggregate, 10 tons per year or more of any hazardous air pollutant or 25 tons per year or more of any combination of hazardou s air pollutants * * *.

( See CAA section 112(a)(1).) An area source is defined as any stationary source of hazardous air pollutants that is not a major source. (See CAA section 112(a)(1).) In the major source definition, the reference to a source ’ s potenti al to emit considering controls allows the interpretation that a

source ’ s potential to emit before and after controls is relevant, such that synthetic minor sources may be considered within the meaning of this definition and included in MACT floor determin ations for categories of major sources. 13 Some commenters appear to suggest that the reference to a source ’ s potential to emit considering controls can only mean a source ’ s potential to emit after controls have been implemented. While it is possible to read the phrase in this manner in isolation, this interpretation would have the effect of excluding the best

- performing sources in a category from MACT floor determinations and therefore would be contrary to the statutory mandate that EPA set MACT floors based on the levels the best

- controlled new sources and the best

- performing existing sources achieve in practice. We believe the statutory reference to potential to emit considering controls should be read in a manner consistent with the other requirements of s ection 112(d) of the CAA to allow for the consideration of synthetic minor sources in MACT floor determinations for categories of major sources.

In addition, the legislative history suggests that synthetic minor sources should be included in MACT floor det erminations. In a floor statement, Senator Durenberger stated that in implementing section 112(d)(3) of the CAA, ‘‘ the [Senate] managers intend the Administrator to take whatever steps are necessary to assure that [the Administrator] has collected data on all of the better

- performing sources within each category. [The Administrator] must have a data

gathering program sufficient to assure that [EPA] does not miss any sources that have superior levels of emission control

. ’’ (See Environment and Natural Resour ces Policy Division, Congressional Research Service, 103d Cong., S.Prt. 103

– 38 (prepared for the U.S. Senate Committee on Environment and Public Works), A Legislative History of the Clean Air Act Amendments of 1990 at 870, Nov. 1993, emphasis added.) This statement underscores that Congress intended for MACT floor determinations to reflect consideration of all of the sources in each category with the best emission controls. We believe it would be inconsistent with Congress ’ s intent and the plain language of the CAA to exclude synthetic minor sources

— those sources with superior controls which became synthetic minor sources by implementing such controls

— from MACT floor determinations.

13 We believe this approach is not inconsistent with our policy that existing sources that limit their potential to emit to below the major source threshold prio r to the first compliance deadline under a MACT standard will not be subject to the standard, as one commenter suggests. (See Memorandum from John S. Seitz, Director, Office of Air Quality Planning and Standards, EPA, to EPA Regions, “Potential to Emit for MACT Standards

— Guidance on Timing Issues,” May 16, 1995.) Including synthetic minor sources in MACT floor determinations ensures that MACT floors reflect the best

- performing sources, as the CAA requires. At the same time, our policy recognizes that

sourc es that already achieve or perform better than the MACT floors need not be subject to the MACT standards.49 We believe that the inclusion of synthetic minor sources in MACT floor deter minations is justified because of the reasons explained above.

Comment 3 : Commenter 0554 stated it does not appear that the EPA excluded startups and shutdowns from the data used to determine the MACT floor. See 79 FR 75626. The commenter stated by includi ng such data in its floor analysis, EPA inflated the proposed limits substantially (especially in light of the variability adjustment). The commenter stated that inflation is wholly unjustified if the limits do not apply during startup and shutdown; startu p and shutdown emissions do not reflect the sources ’ actual emissions during other operations.
Response 3 : The EPA does not agree with the commenter ’ s statement that EPA included startups and shutdowns from the data used to determine the MACT floor. The EPA does not have any data during startup or shutdown periods to exclude from the data set.

Comment 4 : Commenter 0543 requested that the impact of counting co

- vented sources twice in a floor calculation be reevaluated.
Response 4 : The EPA disagrees with the commenter. Co

- vented sources were treated as separate sources as opposed to one source

, to be consistent with the methodology used in the Mercury and Air Toxics Standards ( MATS )

. Having co

- vented sources ’ data repeated in a floor calculation does not a lways bias the variability one way.

There are several components of the UPL equation that have an effect on the final UPL value

-- the average of the data in the MACT floor pool, variability of the data in the MACT floor pool,
t

- statistic, and “ m ” future com pliance term. Adjusting any one of these can affect the values of the other terms and the final UPL value.

In general, the variability within the test runs for the unit affects the variability of the entire MACT pool. If the run

- by

- run data of the unit has little variability, then removing the duplicate kiln from the MACT floor pool will usually increase the overall variance and increase the UPL value. If the run

- by

- run data of the unit has significant variability, then removing the duplicate kiln from the MACT floor pool will usually decrease the overall variance and decrease the UPL value.

7.3.2 Equivalent Limits

A major public comment on equivalent limits and the EPA ’ s responses to that comment can be found in section V.A of the preamble to the BSCP final rule. The remaining public comment on that subject and EPA ’ s response is presented below.

Comment 1: Commenter 0519 noted that, for sources in the Brick and Structural Clay Manufacturing category, the EPA proposed two compliance options for Hg and total n on

- Hg HAP metals: a numerical emission rate limit as a mass of pollutant emitted per ton of bricks produced and a numerical emission limit in units of concentration. The commenter expressed concern that through the use of the mass

- based option, there will be many smaller kilns that will be able to meet the standard without the use of additional pollution controls. The commenter asserted that this outcome is not only inconsistent with the intent of section 112 of the CAA , but50 by allowing a significant number of sources to avoid additional controls altogether, it will limit the degree of health protection expected from this program.
Response 1: The EPA has set standards based on mass per ton of production/output for several industry rules, including Portland C ement, MATS, Boilers, etc. The EPA does not agree that through the use of the mass

- based option, small kilns will automatically be able to meet the lb/ton limits just because their production rate is smaller. That statement assumes the pounds of emissions for a small kilns are not relative to the amount of product going through the kiln

. The EPA is retaining the lb/ton limits for PM and Hg in the final rule.

7.3.3 3xRDL

Comment 1: Commenter 0554 stated for source datasets that contained BDL or DLL data, aft er the subcategory UPL is calculated, the EPA compares the results to “ the 3xRDL value of the relevant performance test method(s)

, ” where “RDL” means “representative detection level.” MACT Floor Memo

- Brick at 9; see also MACT Floor Memo

- Clay Ceramics a t 11. The commenter stated after a conversion step, the 3xRDL is compared to the calculated UPL; as the EPA explains:

“ If the calculated UPL value was less than the 3xRDL value, the 3xRDL value was used as the basis for the standard because the 3xRDL value provides the lowest emission rate that can be measured using the performance test method while maintaining a relative method precision on the order of 10 to 20 percent of the measured value. If the UPL value was equal to or greater than the 3xRDL value, t hen the UPL value was used as the basis for the standard. ” MACT Floor Memo

- Brick at 10; see also MACT Floor Memo

- Clay Ceramics at 11.

Commenter 0554 stated the following standards are based on the 3xRDL value rather than the UPL:

• New brick tunnel kilns (for non

- Hg HAP only)

• Existing clay ceramics floor tile press dryers

• Existing clay ceramics tile glaze lines (for Hg only)

• New clay ceramics floor tile press dryers

• New clay ceramics floor tile spray dryers

• New clay ceramics wall tile spray dryers

• New cla y ceramics tile glaze lines for Hg

Commenter 0554 stated the EPA did not “ demonstrate with substantial evidence ” that a 3xRDL value represents the level achieved in practice by the best performing source or sources, as is required by CAA section 1 12(d)(3)

. Ne. Md., 358 F.3d at 954. The commenter stated the record does not show that actual emissions of units reporting emissions below the detection limit are triple the detection limit. The commenter stated the RDL itself has nothing to do with the emission le vel achieved by a source; rather, according to the EPA, it is just the average of the method detection levels that were used by all the sources the EPA considered in its floor calculations for existing sources. EPA, Data and Procedure for Handling Below De tection Level Data in Analyzing Various Pollutant Emissions Databases for MACT and RTR Emissions Limits 1 (Dec. 13, 2011), EPA

- HQ

- OAR

- 2013

- 0291

- 0133. The commenter stated method detection51 levels are, themselves, simply the levels at which the laboratories that evaluated emission test results for the relevant sources could provide non

- zero readings; none of the method detection levels EPA considered is in any way an estimate of any source ’ s performance, let alone the performance of the best performing source or sources; nor does the average of those method detection levels purport to be an estimate of any source ’ s performance. The commenter stated therefore, a number equal to three times the RDL is not an estimate of the single best source ’ s emission level an d cannot possibly satisfy CAA s ection 1 12(d)(3) ’ s floor requirements.

Response 1: The purpose of the 3xRDL value is to confirm that a MACT floor value will be at a measureable value. UPLs developed from test data with BDL and DLL runs have a level of measureable uncertainty. If a calculated UPL is below the 3xRDL, then that means setting the MACT floor limit at the UPL would be setting the standard at a potentially unmeasurable value. The EPA used the data from the sources in each MACT floor pool to co nvert the standard 3xRDL value 14 into the units of measure of each UPL in order to be comparable. As such, the 3xRDL values are related to the sources in the MACT floor pools.
7.3.4 Floor Calculations for Alternate Approaches

Comment 1: Commenter 0540 state d in setting the alternate BSCP MACT floor for New Small Tunnel Kilns, the EPA deviated from the methodology presented in the memorandum for applying the upper prediction limit to limited datasets by setting arbitrary conditions on the variability for sele cting the best performing small kiln. As presented in the memo, the EPA decided that while the variability of the lb/ton test results for Kiln 599 is acceptable, the variability of the equivalent grains per dry standard cubic foot ( gr/dscf ) test results is not. The commenter stated this decision is based upon the determination that the variability of the equivalent gr/dscf results is approximately twice that of the dataset for the pool of best performing units used to calculate the existing source MACT floo r. The commenter could not make the same conclusion; using the concentration data presented in Appendix_B

1_Proposed_Standards_Existing_Source_UPL_Tables.xls, the variance of the existing source dataset is 7.3E

- 5 which is higher than that of Kiln 599.

Res ponse 1: The commenter is correct that the EPA followed limited dataset guidance when dealing with the alternate BSCP MACT floor for New Small Tunnel Kilns. However, the

c ommenter ’ s reference of the variance of the existing dataset is 7.3E

- 5 from Appendix_ B

1_Proposed_Standards_Existing_Source_UPL_Tables.xls is an incorrect reference because that is the variance for the proposed PM gr/dscf at 7 percent oxygen ( O 2 ) standard, NOT the variance for the alternate PM gr/dscf at 7 percent O 2 Small Tunnel Kiln standard. The variance of the alternate PM gr/dscf at 7 percent O 2 standard for Small Tunnel Kilns existing dataset is 1.2E

6 from the ” PM

- Small

- conc ” worksheet of the Appendix_B

3_Alternate_Standards_Existing_Source_UPL_Tables.xlsx file [EPA

- HQ

- OAR

- 2013

- 0291

- 0119].

14 Westlin, P.

, and R. Merrill. Data and procedure for handling below detection level data in analyzing various pollutant emissions databases for MACT and RTR emissions limits . Memorandum from Peter Westlin, SPPD/MPG and Raymond Merrill, AQAD/MTG, to SPPD man agement and MACT rule writers. December 13, 2011. Docket Item No. E PA

- HQ

- OAR

- 2013

- 0291

- 0133

.52 The Kiln 599 gr/dscf at 7 percent O 2 variance is 1.8E

- 6 . As such, the EP A ’ s determination that

“ the variability of the equivalent gr/dscf results is approximately twice that of the dataset for the pool of best performing units used to calculate the existing source MACT floor ” is accurate because 1.8E

- 6 divided by 1.2E

- 6 is approximately 2.

Further, t he EPA has revised its methodology for oxygen correcting data and is now using 17 percent. The EPA has also revised it ranking met hodology for the equivalent limits to use the

same units of measure for ranking as for the floor calculation (at proposal used lb/ton ranking for equivalent floor limits)

. The limited dataset issue of the new source variance being approximately twice that of the existing source variance is no longer an issue. In addition for those sources that did not have a reported O 2 percent available, they were not oxygen corrected and further removed from the oxygen corrected concentration rankings. Please see the MACT floor memo for the final rule for more information about the rankings and units used to calculate the new source limits.

Comment 2: Commenter 0540 stated in regards to the alternate small tunnel kiln equivalent PM gr/dscf at 7 percent O 2 new source limited dataset, even if selection of a different kiln as the best performer is considered, the logical progression would be to consider the second ranked kiln in terms of lb/ton, Kiln 549. The commenter stated the alternate MACT floor using da ta for Kiln 549 is 0.0065 gr/dscf, which is directly comparable to that of the top ranked kiln, Kiln 599 at 0.0072 gr/dscf.
Response 2: The commenter is correct that the logical progression would be to consider the second rank kiln in alternate small tunne l kiln equivalent PM gr/dscf at 7 percent O 2 new source limited dataset evaluation. The EPA did consider t he second ranked unit, 549, and it was not chosen for the basis of the new source because the average of kiln 549 was 3.7E

- 3 which

was greater than th e existing alternate equivalent small tunnel kiln PM gr/dscf at 7 percent O 2 MACT pool average of 2.9E

- 3 ; which results in a new source alternate equivalent small tunnel kiln PM 0.0065 gr/dscf at 7 percent O 2 UPL greater than the existing source alternate equivalent small tunnel kiln PM 0.0050 gr/dscf at 7 percent O 2 UPL. In accordance with the limited data set memo, EPA has the discretion to review the data from alternate units that would provide a more representative new source limit, as such the EPA revi ewed and set the small tunnel kiln equivalent PM gr/dscf at 7 percent O 2 new source floor on the third ranked unit 665

.

Further t he EPA has revised its methodology for oxygen correcting data and is now using 17 percent. The EPA has also revised it ranking methodology for the equivalent limits to use the same units of measure for ranking as for the floor calculation (at proposal used lb/ton ranking for equivalent floor limits). In addition for those sources that did not have a reported O 2 percent available, they were not oxygen corrected and further removed from the oxygen corrected concentration rankings. Please see the MACT floor memo for the final rule for more information about the rankings and un its used to calculate the new source limits.

Comment 3: Commenter 0540 stated any further consideration of Kiln 665 as the best performing kiln for setting the alternate equivalent standard should address the lack of a measured oxygen content for the data being used. The commenter stated in correcting the measured PM concentration to 7 percent , the EPA assumed the oxygen content in the stack was53 zero; based on other available stack test data, the average oxygen content is approximately 17 percent

. 15 The comm enter stated at this level, the UPL is 0.0278 gr/dscf at 7 percent O 2

. Commenter 0540 stated this comment is in direct response to the EPA ’ s request for comment on any of the alternate approaches under consideration.

Response 3: The commenter is correct th at kiln 665 gr/dscf at 7 percent O 2 data were incorrectly oxygen corrected . This occurred because kiln 665 did not have a reported O 2 percent available and as the commenter identified 0 percent was erroneously used in the calculation

.

The EPA has since rev iewed all the brick tunnel kiln PM test data

, identified sources that did not have a reported O 2 percent available , revised data to not ox ygen correct their concentration to 17 percent O 2 ( revised from 7 percent at proposal to 17 percent for final)

, and further removed them from the oxygen corrected concentration rankings. As a result kiln 665 is no longer in the alternate small tunnel kiln equivalent PM gr/dscf at 7 percent O 2 ranking. Please see the MACT floor memo for the final rule for more inform ation about the rankings and units used to calculate the new source limits.
7.4 Achievability of Standards

Comment 1: Commenters 0551, 0562, 0558, 0516, 0545, 0553, 0548, and 0563 asserted that the EPA has set unreasonably low Hg and non

- Hg metals limits t hat do not reflect the requirements of the CAA and that these limits should be revised. Alternatively, Commenter 0553 stated the Hg and non

- Hg metals limits should be eliminated from the rule.

Commenters 0551, 0562, 0558, 0516, 0545, and 0548 stated if num eric limits remain in the final rule, all three compliance alternatives should remain or EPA should re

- propose this rule. Commenter 0553 stated EPA should reevaluate the cost impacts of this rule.

Commenter 0563 stated their North Carolina operations, ther e are two controlled kilns and 4 uncontrolled kilns which operate or don ’ t operate depending on demand for products; the controlled kilns have DLAs. The commenter stated that they have not been required to conduct a stack test for Hg emissions from their k ilns, so they cannot be certain that they can comply with any of the compliance options. The commenter is currently participating in an industry raw material testing program to determine whether these limits are attainable for their operations.

Commenter 0545 stated the CAA was never meant to be a technology driver; this seems to be entirely contradicting that; there seems to be little to no proof that available technologies can achieve the levels warranted in the MACT.

Response 1: The EPA does not agree with the commenter that the Hg and non

- Hg limits are unreasonably low and do not reflect the requirements of the CAA. As such, the EPA is retaining the Hg and non

- Hg limits, but with some revisions. The EPA has received Hg raw materi al data during the comment period. The EPA has evaluated the data and developed a raw material

15 Attachment to Memorandum “Test Data Used in BSCP Proposed Rule,” Docket Item No. EPA

- HQ

- OAR

- 2013

- 0291

- 0121, November 6, 2014.54 variability factor that has been incorporated into the variability of the MACT floor pool data for each Hg MACT floor UPL equation. Please see the MACT floor mem o for the final rule for more information. The EPA is also retaining the alternative concentration (μg/dscm at 17 percent O 2 ) and emission rate (lb/hr) floors in addition to the emission factor (lb/ton) MACT floors. The EPA also revised the calculation of the n on

- Hg t otal HAP limit, discussed further in the MACT floor memo for the final rule.55 8.0 Health

- Based Standards

8.1 Health Thresholds

The major public comments on health thresholds and the EPA ’ s responses to those comments can be found in section V. B of the preamble to the BSCP final rule. The remaining public comment and EPA ’ s response are presented below.

Comment 1 : Commenters 0547 and 0549 stated that

, as EPA demonstrate d in the proposed rule, the available health data indicate that HCl, HF, and Cl 2 are all threshold pollutants. The
commenter stated that the data show that each of these pollutants has a discernible exposure threshold below which adverse human health effects are not expected to occur; in addition, none of the available data suggest that these pollutants reasonably should be expected to act as a carcinogen or mutagen, or exhibit a mode of action that would result in non

- threshold effects. See 79 FR 75638

- 75641.
Response 1 : The EPA appreciate s the commenters ’ support for EPA ’ s conclus ions that the acid gases HCl, HF, and Cl 2 are threshold pollutants.
8.2 Discretionary Authority

The public comments on co

- benefits, ecosystem impacts, and cumulative effects and EPA ’ s responses to those comments can be found in section V.B of the preamble to the BSCP final rule.

8.3 Setting Level of Standard
8.3.1 Ample Margin of Safety

The public comments on ample margin of safety and the EPA ’ s responses to those comments can be found in section V.B of the preamble to the BSCP final rule.

8.3.2 Risk Assess ment
The major public comment on risk assessment and the EPA ’ s response to that comment can be found in section V.B of the preamble to the BSCP final rule. The remaining public comment and EPA ’ s response are presented below.

Comment 1 : Commenter 0546 stated that the rationale and accompanying technical documents make it very difficult or impossible to determine the impact of this rule because they never report the ambient air concentrations that would result if this rule were adopted an d compare that to what they would be if the usual MACT approach were used. The commenter noted this is an essential step in any assessment process, because it is there concentrations that are germane to estimate exposures or to compare to concentrations al ready known to represent various hazards or risks.

Commenter 0546 stated there are concerns here for both acute and chronic effects, so this omission seems especially unfortunate. The commenter stated the attention of the writers was on56 the modeling of the emissions but that should not preclude estimation of what is related to health effects, which is the ambient concentration.

Response 1 : The EPA disagrees with the commenter ’ s assertion that there was insufficient information provided to determine the impa ct of the rule. The purpose of EPA ’ s risk assessment was to determine an emissions level that would ensure adverse health effects would not occur at any facility in the source category. The EPA did this by assigning the HBEL level of emissions to each faci lity, then determining whether that emissions level resulted in a chronic target organ

specific hazard index ( TOSHI ) exceeding one (or the potential for acute health effects) at any facility . The purpose of the assessment was not to characterize the expos ures at each facility due to the HBEL emissions level (beyond ensuring no health effects), nor to assess the ambient concentration at each facility that would result after the application of MACT. However, the docket does include the model input files the commenter would need to generate each facility ’ s estimated ambient concentration . The model itself, the Human Exposure Model 16 is also publicly available.

8.3.3 Level of Standard

Comment 1: Commenter s 0543 , 0547, 0549, and 0558 supported the health

- based approach for acid gases, but stated that an overly conservative approach was used to establish the limit.

C ommenter 0543 contended that the current proposed approach of setting a single “ one limit fits all ” for the entire industry is overl y restrictive and would cause at least one facility to install controls with no benefits. The commenter noted that single limit based on a single worst

- case source needlessly limits the potential for all facilities to expand at their current locations. The commenter stated that expansion close to raw materials is important in the brick industry because the mineral content and other properties of their locally mined raw materials give each brick its distinctive look

. The commenter stated that there is no rea son to limit growth for an existing plant when there is no adverse impact on the environment.

Despite using worst

- case modeling , the commenter noted that no facility was over 0.4 cumulative for all kilns in any single hour . The commenter stated that this d emonstrates no facility should have to control acid gas emissions

. Despite all facilities modeling well below the safe level, the commenter stated that the EPA ’ s proposed allowable emission level cannot be met by one facility and limits expansion and flexi bility at other facilities. The commenter noted that the EPA identified Belden Brick in Sugarcreek, Ohio as the facility that would not be able to meet the health

- based hourly emission limit for acid gases, however Belden ’ s cumulative HI when modeled using actual emissions and stack parameters is only 0.28. The commenter noted this indicate s the concentrations at the fence

- line would be below EPA ’ s safe levels even at maximum emissions . The commenter asserted that the proposed rule would needlessly require Belden to add controls to meet an overly restrictive emission limit that is well below levels required to protect human health and the environment . The commenter argued there is no justification to require this facility to install multimillion dollar contr ols. The commenter assert ed

16 http://www2.epa.gov/fera/risk

- assessment

- and

- modeling

- human

- exposure

- model

- hem57 that there should be no costs incurred when there is no benefit. Commenter 0558 concurred with this comment.

C ommenter 0543 asked the EPA to consider whether a large source, such as Belden, that can demonstrate no adverse impact s, but is over the conservatively set limit represents a different subcategory. If the EPA promulgates only one limit, the commenter suggested the limit must be higher.

Commenters 0547 and 0549 suggested the EPA ’ s approach means that for most facilities in the source category the HBEL emission standard would more stringent than needed to meet the section 112(d)(4) “ ample margin of safety ” criterion and would impose needless restrictions on current operations and growth. The commenters stated that this is an unreasonable and arbitrary and should be rectified by setting multiple HBEL emission standards to accommodate facilities with specified emissions and site characteristics. Given the relatively limited number of affected facilities in this source category, the commenters suggested that this approach should not be out of the question. Commenter 0547 noted the EPA already has “ site specific data on the operation of each tunnel kiln. ”

The commenters further asserted that the EPA has the legal authority to tak e this approach because CAA s ection 112(d)(1) states that the EPA “ may distinguish among classes, types, and sizes of sources within a category or subcategory in establishing standards

. ” The commenters stated that this would fulfill Congress ’ s clear intent that MACT emissions standards should not be “ far more stringent than is necessary to protect public health and the environment. ” S. Rep. No. 101

- 228 at 171.

While disagreeing with the setting of a single limit for all sources

, C ommenter 0543 asserted the EPA has established the proposed limit incorrectly. The commenter noted that i n setting the proposed emission limitation, the EPA modeled impacts a n emission rate of 1 tpy from kilns at active, major sources in the category, and selected the facility with the highest modeled chronic impact to derive an emissions level equivalent to a TOSHI of one. Following the EPA ’ s methodology, Commenter 0543 stated that the top three ranking sources (i.e., worst performing) with respect to their modeled chronic impacts a re : (1) International Chimney Corporation ’ s Continental Clay facility in Kittanning, P ennsylvania ; (2) Interpace Industries Inc. located in Ogden, U tah ; and (3) American Eagle Brick Co., located in Sunland Park New Mexico.

The commenter suggested that the first two facilities should be removed from the risk assessment because they do not meet the criteria of being active, major sources as specified in EPA ’ s technical memorandum. The commenter stated that, per Pennsylvania Department of Environmental Protec tion records, the Continental Clay facility is a true area source of HAP and is not within the source category being regulated. The commenter also noted that, according to a local Ogden, Utah publication, the Interpace Industries Inc. facility ceased opera tions in 2012 and will not continue as a brick

- manufacturing facility under its new ownership.

The commenter stated that they reevaluated the health

- based emissions limit using the modeled chronic impact posed by the American Eagle Brick Co. facility and d etermined that a non

- cancer TOSHI of one yields an emission level of 92 lb/hr HCl equivalent. Since the 92 lb/hr level of58 HCl

- equivalent emissions is determined such that no facility would exceed a TOSHI of one, the commenter suggested that no facility in individual acid gas model runs should exceed this level.

Response 1 : The EPA disagree s with the commenter that the emission limit should be raised to 92 lb/hr HCl equivalent

. The commenter does correctly list the facilities with the highest estimated TOSHI associated with chronic exposures, but there are other facilities that have the highest estimated acute hazard quotients. For the proposed limit of 57 lb/hr HCl equivalent emissions, the EPA concluded that the re would be low potential for acute health eff ects for all facilities ; however, increasing that limit by over 60 percent would increase the likelihood of acute health effects and would lessen the ample margin of safety

. Therefore, the EPA has not revised the emission limit in the final rule.

8.3.4 Oth er The major public comments and the EPA ’ s responses to those comments can be found in section V.B of the preamble to the BSCP final rule . The remaining public comments and EPA ’ s responses are presented below.

Comment 1 : Commenter 0546 stated that studies have been published since the entries to the EPA IRIS database for the substances at issue, and these are readily available; especially when the database entries are 20 years old as in this case, EPA needs to consider the relevant scientific literature.

Re sponse 1 : The EPA disagrees with the commenter that more recent studies necessarily represent the best science. The EPA has an approach for selecting appropriate chemical specific toxicity assessments and health effect reference values

, which is prioritized according to (1) conceptual consistency with EPA risk assessment guidelines and (2) level of review received. 17 This prioritization approach, which favors EPA toxicity assessments and reference values when they exist, has been endorsed by the EPA’s Science Advisory Board ( SAB )

. As part of the risk analysis conducted to support this rule

, EPA thoroughly evaluated all the available and relevant scientific evidence of the substances at issue ( see summary of the evidence in section V.A of t he preamble to the final rule ) and concluded that the current toxicity assessments and associated health effects reference values for HCl, Cl 2 and HF from EPA, ATSDR and California EPA, respectively, are the most appropriate assessments and reference value s to use in support of this regulatory decision.

Comment 2 : Commenter 0546 stated that greater attention is needed to the environmental fate of Cl 2 ; the gas may not last long in the environment but that is because it becomes an acidic liquid when coming in to contact with water or the lungs. The commenter noted it does not disappear; the document seems rather ill informed about this.

17 S cience A dvisory B oard. Memorandum to Lisa Jac kson, Administrator, U.S. EPA. R eview of EPA’s draft entitled, “Risk and Technology Review ( RTR ) Risk Assessment Methodologies : For Review by the EPA’s Science Advisory Board with Case Studies

– MACT I Petroleum Refining Sources and Portland Cement Manufac turing

. ” May 7, 2010. A vailable at: http://yosemite.epa.gov/sab/sabproduct.nsf/4AB3966E263D943A8525771F00668381/$File/EPA

- SAB

- 10

- 0 07

- unsigned.pdf

.59 Response 2 : The EPA did not state that Cl 2 disappear s in the environment, rather the EPA describes Cl 2 as a gas that is highly reactive with both organic and inorganic substances that comes into contact with. When Cl 2 gas is released into water, such as during water chlorination, it quickly dissolves and converts into chloride and hydrochlorous acid. With regard to inhaled Cl 2 , at low levels (1

- 5 parts per million ( ppm ) ) , 95 percent of the Cl 2 that touches the lung surface is rapidly cleared from the respiratory system with chloride eventually joining the chloride pool that already exists in the body. 18

Comment 3 : Commenter 0548 stated their company is currently permitted under North Carolina 112j using the health

- based standard. The commenter stated that K iln #696 with a DLA control device is subject to certain recordkeeping and reporting requirements associated with its
ope ration; the other, uncontrolled kilns are subject to recordkeeping and reporting requirements under work practices. The commenter stated that testing requirements are also in place to verify compliance with modeled emission rates. The commenter support ed EPA ’ s decision to propose a health

- based approach and work practices in the standard. The commenter stated this has shown to work well for facilities in North Carolina; North Carolina should be used as a model for application of the standard.
Response 3 : The EPA appreciate s the commenter ’ s support for the health

- based emission limit.

Comment 4 : Commenters 0521 and 0545 noted that while they believe it is a reasonable assumption that the health

- based limits can be achieved without additional control, their facilities have not tested for Cl 2 ; as a small amount of Cl 2 will have a significant impact on the compliance determination, they cannot be assured that they will meet the health

- based limits until they stack
test.
Response 4 : The EPA appreciates the commenters ’ concern, but o ur impacts estimates indicate that all BSCP facilities except one will be able to meet the health

- based emission limit. (reference promulgation impacts memo

-- to be drafted ). Our test data also show Cl 2 emissions are, on average, a factor of ten less than HCl (reference promulgation test data memo

-- to be drafted)

.
8.4 General Support

Comment 1: Multiple commenters (0514

- 0516, 0520

- 0523, 0528

- 0530, 0535

- 0537, 0543, 0545, 0547

- 0553, 0555, 0556, and 0560

- 0563) commended the EPA for making positive steps in this regulation with health

- based standards for acid gases and work practice standards in lieu of numeric limits. However, the commenters suggested that additional steps are required to make this rule reasonable and attainable.

Commenter 0530 commended the EPA on the cooperation and willingness it has shown in considering and evaluating the data and testimony provided by their industry. The commenter was pleased that the EPA evaluated that data along with its own to reach the conclusion that a health

- based approach will protect the environment and public safety while at the same time reducing the tremendous financial burden faced by their industry without a health

- based rule.

18 U.S. Department of Health and Human Services, Agency for Toxic Substances and Disease Registry. Toxicological Profile for Chlorine. 2010. Available at http://www.atsdr.cdc.gov/toxprofiles/tp172.pdf

.60 The commenter noted that the health

- based approach covers over ninety

- nine percent of their industry ’ s emissions.

Response 1: The EPA appreciate s the c ommenters ’ support for the health

- based emission limit.61 9.0 Work Practice Standards

Comment 1: Multiple commenters (0521, 0545, 0550, 0551, 0552, 0553, and 0562) provided general support of EPA ’ s proposal of multiple work practice standards in lieu of nu meric limits. None of their concerns with other provisions of the proposed rule take away from their support of that decision.

Commenter 0554 asserted that the work practice standards that EPA proposed to set for dioxin/furan emissions from brick tunnel ki lns, startup and shutdown period emissions for all brick plants, and for all emissions from brick periodic kilns do not satisfy the CAA ’ s requirements. The commenter ’ s rationale for their objection to the work practice standards for dioxin/furan emissions and periodic kilns is summarized later in this section. The commenter ’ s rationale for their objection to the startup and shutdown period emissions is summarized in section 10.0 of this document, “ Startup and Shutdown. ”

Commenter 0554 noted that section 1 1 2(h) of the CAA allows EPA to set a work practice standard for a category or subcategory of industrial sources, only if it is “ not feasible ... to prescribe or enforce an emission standard for control of a hazardous air pollutant or pollutants. ” Congress d efines in the statute “ not feasible to prescribe or enforce an emission standard ” as meaning that:

(A) a hazardous air pollutant or pollutants cannot be emitted through a conveyance designed and constructed to emit or capture such pollutant or that any req uirement for, or use of, such a conveyance would be inconsistent with any Federal, State or local law, or

(B) the application of measurement methodology to a particular class of sources is not practicable due to technological and economic limitations.

Id

. CAA s ection 1 12(h)(2). If this requirement is met, the work practice standard nonetheless must be “ consistent with the provisions of subsection [ 1 12](d). ” Id

. CAA s ection 1 12(h)(1).

Response 1: The EPA appreciates the support from multiple commenters for t he work practice standards. The EPA ’ s responses to Commenter 0554 regarding their objection to the work practice standards for dioxin/furan emissions and periodic kilns are provided later in this section. The EPA ’ s response to the Commenter 0554 regarding their objection to the work practice standard for startup and shutdown period emissions is provided in section 10.0 of this document,

“ Startup and Shutdown. ”

Comment 2: Commenter 0543 stated that the proposed work practice requirements for control of dioxi n/furan emissions from tunnel kilns are acceptable and reasonable. Since tunnel kilns are designed to operate for extended periods of time, the maximum of a 3

- year time period between checks will allow owners and operators to check the systems during norma l shutdown and maintenance time. The commenter requested that the EPA allow the inspections conducted within 3 years of the initial compliance demonstration to be accepted.

Commenter 0554 disagreed with the proposed work practice standards for tunnel kilns ’ emissions of dioxins/furans. The commenter noted that even if was authorized to set work62 practice standards for these emissions, the work practice standards the EPA proposed would contravene CAA section 1 12(h)(1). To be consistent with CAA section 1 12(d) , as section 1 12(h)(1) requires, any work practice standards would have to reflect measures that yield the maximum achievable degree of reduction in these pollutants (i.e., pollutant reductions consistent with the reductions that would be achieved by a num erical standard) and that at a minimum reflect the measures adopted by the facilities with the lowest emission levels of dioxins/furans. The commenter noted that the EPA ’ s proposal did not purport to satisfy this requirement: these standards merely require sources to maintain and periodically tune up their kilns. The EPA did not attempt to show what level of emissions reduction, if any, such requirements would achieve, and the record

- keeping and reporting requirements themselves are neither work practices n or means for reducing emissions.

Commenter 0554 stated that the EPA ’ s previous MACT rules, including its standards for medical waste incinerators, show that the EPA knows perfectly well that the composition of the fuel being burned, temperature of the burner, the residence time in the burner, the temperature of the gas exiting that burner, the rapidity of the cooling of the gas, and the temperature of the air pollution control device all have significant effects on dioxin emissions. EPA, Chlorinated Dio xin and Furan Formation, Control and Monitoring (1997).

Commenter 0554 also stated that the EPA is well aware that dioxin/furan emissions are influenced by factors such as the content of surface coatings, body additives, and raw materials, as well as the f uel fired in the kilns, and that these factors could be addressed through work practice standards. See National Emission Standards for Hazardous Air Pollutants for Brick and Structural Clay Products Manufacturing; and National Emission Standards for Hazard ous Air Pollutants for Clay Ceramics Manufacturing, 67 FR 47984, 47907 (July 22, 2002) ( “ HAP metals may emanate from trace quantities of metals found in raw materials, metallic body additives and surface coatings commonly used in the industry, or from the fuels fired in the kilns. ” ); Id . at 47899. It is completely arbitrary and unlawful that these work practice standards do not even include limits on firing times, temperature cycles, and maximum loads that the EPA is proposing for brick and clay periodic ki lns, see 79 FR 75646, or requirements to use natural gas as the kiln fuel, as the EPA is proposing for clay ceramics sanitaryware shuttle kilns, Id . at 75663.
Response 2: The EPA appreciates the support from Commenters 0543 for the work practice standards for dioxin/furan emissions from tunnel kilns. We agree with the commenter ’ s request to allow the inspections conducted within 3 years of the initial compliance demonstration to be accepted as the initial compliance demonstration as long as the inspection m et the requirements of the regulation. The subsequent inspection must occur no later than 36 calendar months after the previous tune

- up.

The EPA disagree s with Commenter 0554 that the standards do not address dioxin/furan emissions from tunnel kilns. As noted in the preamble to the proposed rule (79 FR 75647), the work practice standard ensures that equipment is maintained and run so as to minimize emission s of dioxins and furans. Dioxins/furans are products of incomplete combustion (PIC) and optimizing combustion limits the formation of PICs , thereby minimizing emissions of dioxins/furans. Optimizing combustion addresses many of the factors noted by the com menter, such as temperature and residence time. The analogy that the commente r provided with regard to HAP metals is not applicable in this case, since any d ioxin/f uran from BSCP kilns would be63 formed as a result of incomplete combustion, and not due to an y dioxins/furans in the raw materials, additives, or coatings.

Comment 3: Commenter 0516 stated that the EPA has proposed logical and practicable work practice standards for periodic kiln operations and noted that the requirements are feasible and applicab le. Commenter 0543 agreed that the proposed work practice requirements for periodic kilns are acceptable and reasonable and requested that the EPA clarify that the facility may opt to list the maximum load on the required label in either dry or fired tons.

Conversely, Commenter 0554 stated that the EPA ’ s proposed work practice standards do not reflect measures that yield the maximum achievable degree of reduction in these pollutants (i.e., pollutant reductions consistent with the reductions that would be ac hieved by a numerical standard) and that at a minimum reflect the measures adopted by the periodic kilns with the lowest emission levels. Therefore, they are not “ consistent with ” CAA section 1 12(d) and violate CAA section 1 12(h). The proposed standards do not reflect the use of any control technology at all. EPA is well aware that hazardous air pollutant emissions are influenced by factors such as the content of surface coatings, body additives, and raw materials, as well as the fuel fired in the kilns, an d that these factors could be addressed through work practice standards. See 67 FR 47907 ( “ HAP metals may emanate from trace quantities of metals found in raw materials, metallic body additives and surface coatings commonly used in the industry, or from th e fuels fired in the kilns. ” ); Id . at 47,899. At a minimum, EPA could require sources to use natural gas (or the cleanest available alternative) as a fuel. Cf. 79 FR 75663 (proposed work practice standards for clay ceramics sanitaryware shuttle kilns would require each kiln “ to use natural gas or equivalent as the kiln fuel ” ).

Response 3: The EPA appreciate s the support from Commenter s 0516 and 0543 for the work practice standards for periodic kilns. However, we are not revis ing the work practice standard s to allow facilities to list the maximum load in either dry or fired tons. The maximum load refers to the tons of product that can be fired in the kiln during a single firing cycle and is compared to the total tonnage of product placed in the kiln, which i s referring to dry tons (before firing) and not fired tons (after firing).
As provided under CAA section 112(h)(1), a work practice standard "reflects the best technological system of continuous emission reduction which (taking into consideration the cost of achieving such emissions reductions, and any non

- air quality health and environmental impact and energy requirements) the Administrator determines has been adequately demonstrated. The EPA disagree s with Commenter 0554 that the work practice stand a rds f or emissions from periodic kilns do not address emissions from those sources . As noted in the preamble (79 FR 75645

- 6), “ information provided to the EPA indicates there are six operational factors that have a direct bearing on HAP emissions from BSCP perio dic kilns: Temperature, firing cycle, product quality, automatic control, combustion control and kiln load/kiln technology. ” The work practice standards address each of these factors to limit the emissions from periodic kilns.64 10.0 Startup and Shutdown

T he major public comments on startup and shutdown standards and the EPA ’ s responses to those comments can be found in section V. B of the preamble to the BSCP final rule. The remaining public comments and the EPA ’ s responses are presented in this section.

Comment 1: Multiple commenters (0516, 0520, 0521, 0528, 0533, 0537, 0543, 0548, 0551, 0553, and 0558) approved of the use of work practice standards for periods of startup and shutdown.

Commenter 0554 stated that the EPA ’ s proposed work practice standards for periods of startup and shutdown are unlawful because the EPA is authorized to set work practice standards only for classes of sources, not for periods of operation. CAA s ections 1 12(d)(1) and (2), read together, demonstrate that separate standards may be set only for categories or subcategories of sources, which must be of a different class, type, or size. The commenter stated that because the EPA does not claim or demonstrate that measurement is impracticable for the categories of brick, or for subcate gories of brick tunnel kilns as a class, the proposed work practice standards are unlawful.

C ommenter 0554 stated that the EPA ’ s statements in support of its proposal to implement work practice standards do not amount to the “ determin[ation] ” required by C AA section 1 12(h) that either section 1 12(h)(2)(A) or (2)(B) has been satisfied. The EPA does not articulate that measurement of emissions during startup and shutdown “ is not practicable ” due to technological or economic limitations. And, to the extent tha t EPA believes work practice standards are authorize d under section 1 12(h)(2)(A), the EPA does not “ determine[] ” that a pollutant “ cannot be emitted through a conveyance designed and constructed to emit or capture such pollutant ” during startup shutdown pe riods. The absence of the requisite statutory determination under section 1 12(h)(2) by the Administrator alone renders the proposed work practice standards unlawful.

Commenter 0554 further stated that the EPA has not satisfied the statutory requirement tha t testing “ is not practicable due to technological ... limitations, ” nor would the record support such a claim with substantial evidence. See Ass ’ n of Data Processing Serv. Org. v. Bd. of Governors of Fed. Reserve System , 745 F.2d 677, 684 (D.C. Cir. 1984) (substantial evidence standard applicable to agency ’ s factual judgments in informal rulemaking); Ne. Md.. 358 F.3d at 954 (applying substantial evidence standard to the EPA ’ s MACT floor determination); NACWA, 734 F.3d at 1138 (same). The EPA ’ s conclusory statements do not constitute a determination of impracticability under CAA section 1 12(h)(2)(A), nor do they amount to substantial evidence that it is not practicable to apply measurement technology during startup and shutdown periods under CA A section 1 12(h)(2)(B). The commenter stated that the EPA has not considered whether measurement methods other than the ones the EPA is proposing could be used for startup and shutdown periods, and the record does not contain information about such methods

. The EPA did not specifically address, or support with substantial evidence, why fluctuating conditions would make it impracticable to measure each type of hazardous air pollutant. The EPA must select a different method for such periods, or make and suppo rt with substantial evidence a determination that no such method is available. Work practice standards are permitted65 only where it is entirely “ infeasible to prescribe or enforce an emission standard, ” not just infeasible during certain periods.

Commenter 0554 noted that the EPA has not claimed that continuous emissions monitoring systems could not be used to measure emissions during startup and shutdown periods, and stated that the EPA must also consider whether the use of mass

- based limits would be techno logically feasible. Methods of estimating emissions during startup and shutdown, such as emission estimates based on the operating parameters of PM controls, could substitute for the direct monitoring of emissions.

Commenter 0554 stated that the problem th e EPA identifies with using the “ equivalent ” emission limits during startup and shutdown is irrelevant to the statutory standard, which is whether use of measurement methodology “ is not practicable due to technological and economic limitations. ” Id

. CAA s e ction 1 12(h)(2)(B). The format of the emissions standard is not a “ technological ” or

“ economic ” limitation, and has no bearing on whether there are methods that are technologically practicable for application to kilns during startup and shutdown. The comme nter stated that

, as the EPA recognized, the emission limits pounds per ton are appropriate and practicable for startup and shutdown periods. Nothing requires the EPA to provide the other “ equivalent ” emission limits, and if such limits are inappropriate f or startup and shutdown periods as the EPA claims, then the EPA need not offer them for such periods. Further, the EPA cannot devise the

“ equivalent ” limits itself (which are not required by the Act), and then point to them as a reason why MACT standards c annot be set for periods of startup and shutdown.

Commenter 0554 further stated that even if the EPA ’ s startup and shutdown work practice standards for plants with APCDs are valid, concerns about those sources ’ ability to vent exhaust through the control d evices lend no support to setting work practice standards for sources that do not employ control devices.

Commenter 0554 stated that the EPA ’ s proposed work practice standards for startup and shutdown periods contravene CAA section 1 12(h)(1) because they do not reflect measures that yield the maximum achievable degree of reduction in these pollutants (i.e., pollutant reductions consistent with the reductions that would be achieved by a numerical standard) and that at a minimum reflect the measures adopted by the facilities with the lowest emission levels during startup and shutdown. The EPA does not claim the work practice standards are “ consistent with the provisions of subsection (d) or (f) ” of section 1 12. The EPA provides no basis for assuming that sources operating during startup and shutdown periods would necessarily meet the pertinent section 1 12(d) numeric limits. Under the proposed work practice standards, sources would not be required to engage their poll ution control devices during startup and shutdown periods, and the recordkeeping and reporting requirements themselves are neither work practices nor means for reducing emissions. Even if the sources are not feeding bricks into the kiln, they will be burni ng fuel (including coal) during those time periods, which will result in hazardous air pollutant emissions that might be higher than the numerical limits.

Commenter 0554 stated that the D.C. Circuit has specifically held that the CAA requires that

“ there m ust be continuous section 112

- compliant standards. ” Sierra Club v. EPA , 551 F.3d 1019, 1027 (D.C. Cir. 2008). But the revised final rule includes no continuous, section 1 12

- compliant66 work practice or other emission standard to limit the rate of emissions d uring startup and shutdown. The commenter suggested that at a minimum, the EPA could require sources to use natural gas or the cleanest available alternative as a fuel during periods of startup and shutdown. Further, the EPA needs to set limits on the time that sources spend in startup and shutdown mode to prevent the startup and shutdown provisions from being abused as a means to avoid compliance with emission standards.

Response 1 : The EPA appreciates the support from multiple commenters for the use of wo rk practice standards for periods of startup and shutdown. As discussed later in this section, the EPA has revised the work practice standards for periods of startup and shutdown for BSCP tunnel kilns to provide requirements for minimizing emissions that a re feasible for all kilns.

The EPA disagrees with Commenter 0554 that work practice standards for periods of startup and shutdown are unlawful. We disagree with the commenter that the standards were set for periods of operation, rather than classes of sour ces. The standards were set for tunnel kilns, which is a subcategory of sources in the BSCP manufacturing source category. We also disagree with the commenter that we did not state that measurement was impracticable due to technological limitations . As we stated in the preamble to the proposed rule, “ we recognize that it is not feasible to conduct emission testing during periods of startup and shutdown. ” 79 FR 75647. The infeasibility of measuring emissions during periods of startup and shutdown is document ed in the memorandum “ Summary of Startup, Shutdown, and Malfunction Data for Brick and Structural Clay Products Industry, ” in the docket for this rulemaking.

The EPA further disagrees with Commenter 0554 that EPA must also demonstrate that a pollutant “ can not be emitted through a conveyance designed and constructed to emit or capture such pollutant ” during startup and shutdown periods

. S ection 112(h)(1) allows work practice standards only if pollution is not emitted through a conveyance or “ the application of measurement methodology to a particular class of sources is not practicable . (emphasis added) As noted in the previous paragraph, the EPA has already demonstrated the latter.

As stated previously, the EPA has revised the standards for promulgation, based on public comments and additional information provided by the BSCP industry following proposal on the procedures used during startup and shutdown for BSCP tunnel kilns that are more representative of the best performing kilns

. Consequently, the EPA is confident that t hese standards will provide the maximum limitation of emissions possible during periods of startup and shutdown, ensuring that the BSCP Manufacturing NESHAP include s continuous section 112

- compliant standards d uring all periods of operation.

Comment 2 : Commenter 0533 asked that the rule language be modified in sections 63.8405 and 63.8420(a) to include an exclusion from the numeric limit for periods of startup and sh utdown

. In support of this request for the rule language change, Commenter 0533 discussed requirements for the determination of an emission limit, and how the EPA had not met those requirements when setting an emission limit that is applied to startup and shutdown periods in the proposed rule. The commenter agreed with the reasons stated in the preamble that support work practice standards for startup and shutdown periods. However, the commenter also questioned whether the EPA had the data and had conducted sufficient analysis to demonstrate the achievability of67 the MACT emission limits established for normal operations during startup and shutdown
events. Commenter 0533 stated the following concerns:

• It is not apparent from the preamble discussion of alterna te standards for startup and shutdown periods that the EPA has actually analyzed sufficient data on emissions during startup and shutdown to justify the Agency ’ s conclusion that, “ the EPA has taken into account startup and shutdown periods .” 79 FR 75626. I nstead, based on the EPA ’ s statements about the timing of startup and shutdown of control equipment, as discussed above, it may be more that the EPA has merely assumed the preamble ’ s discussion to be correct (without need for such analysis).

• There are seve ral reasons why adequate data often do not exist to allow 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, which would c ause t he EPA to understate emissions.

o To the extent emissions data come from required performance tests, the applicable regulations generally prohibit testing during startup, shutdown, and malfunction ( SSM ) conditions, and further require that data not be used for compliance purposes if obtained during a startup, shutdown, or malfunction event. 19

o To the extent the EPA evaluates emissions data collected through continuous monitoring, the applicable regulations often require or allow the source to exclude from its reporting of continuous monitoring data those data reflecting SSM conditions.

o Atypical pollutant concentrations and other stack conditions that may exist during startup and shutdown can result in the continuous monitoring system producing unusable dat a, because the pollutant concentration may be outside of the monitoring equipment ’ s span or the stack conditions may not meet monitoring system QA/QC parameters, or the data may be truncated on the high end because of limitations of the monitoring equipmen t. 20

Commenter 0533 stated 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. Without a clear demarcation (both in EPA regulations and in practice), the EPA may be analyzing data sets that exclude events that the source treated as malfunctions but the Agency would instead say should be included in calculating average performance as startup or shutdown conditions.

Response 2 : The EPA disagrees with the comm enter that we are requiring sources to meet the same emission limits during periods of normal operation and periods of startup and shutdown. As noted in Table 3 to both the BSCP Manufacturing NESHAP and the Clay Ceramics Manufacturing NESHAP, we have set w ork practice standards to apply during periods of startup

19 See, for example, the NESHAP General Provisions, which state that performance tests can only be conducted under representative conditions and which specify that: “Operations during periods of startup, shutdown, and malfunction shall not constitute representative conditions for the purpose of a performance test....” 40 CFR 63.7(e)(1); see also 40 CFR 60.8(c) (same for performance testing for NSPS).

20 Note that data from periods when a monitoring system is outside of control limits are required to be excluded from emission averages under the NE SHAP General Provisions. See 40 CFR 63.8(c)(7)(ii).68 and shutdown. As stated in the previous response, the EPA has revised these standards for promulgation to provide requirements for minimizing emissions that are feasible for all kilns.

Comment 3 : Co mmenter 0533 asserted that emission limitations should not apply at all times, as is implied in 40 CFR 63.8420(a). The c ommenter noted that although the Sierra Club v. EPA (D.C. Cir. 2008) decision recognized that different standards, including non

- numeric al standards, may (and, in some cases, must) apply during non

- standard operating conditions, the Sierra Club decision does not prevent EPA from adopting emission standards for SSM periods that are different from those required during periods of normal oper ation. The commenter stated that the Sierra Club decision does not bar th e EPA from using a “ requirement relating to the operation or maintenance of a source to assure continuous emission reduction ” as the emission standard for SSM events. See 551 F.3d at 1027. The Sierra Club decision only rejected EPA ’ s assertion that it had discretion to decide not to impose any emission standard covering SSM periods. See id . at 1027

- 28, 1030 (noting that EPA was not claiming that the General Provisions SSM exemption

was either an emission standard under CAA section 112(d) or a design, equipment, work practice, or operational standard under section 112(h)). The commenter stated that the majority opinion was that “ Congress gave no indication that it intended the application of MACT standards to vary based on different time periods, ” 551 F.3d at 1028: (1) is contradicted by other statements in the opinion, referenced above, that a MACT standard need not continuously apply a single emission limitation, (2) is dicta, because that was not the situation presented by the challenged regulations and argued by EPA, (3) ignores the extensive case law about technology

based limitations referenced above, and (4) does not in any event say that the CAA precludes EPA from adoptin g different emission limitations that apply during SSM events.

Commenter 0533 stated that Cement Kiln Recycling Coalition v. EPA , 255 F.3d 855 (D.C. Cir. 2001) is the only court decision that addresses SSM issues under CAA section 112

, and noted the decisi on for this case is consistent with Essex Chemical and the other new source performance standard ( NSPS ) cases. In Cement Kiln Recycling Coalition , the D.C. Circuit court decided to vacate the standards part ly because of the Court ’ s concerns about EPA ’ s fai lure to exempt hazardous waste combustors from numerical emission limits during SSM periods, instead of

“ permitting sources to return to compliance by following the steps of a startup, shutdown, and malfunction plan filed with the Agency.... ” The Court had “ similar doubts about EPA ’ s decision to require sources to comply with standards even during openings of emergency safety valves caused by events beyond the sources ’ control. ” Id . at 872. In response to that decision, EPA revised the rule to exempt facili ties from the limitations during SSM events. See 40 CFR 68.1206(b)(1); 67 FR 6792, 6798, 6813 (February 13, 2002).Commenter 0533 disagreed with the EPA ’ s statement that its treatment of excess emissions during SSM events was “ required ” in order to make the standards “ consistent with ” the D.C. Circuit ’ s decision in Sierra Club v. EPA

, 551 F.3d 1019 (D.C. Cir. 2008), cert. denied, 130 S. Ct. 1735 (2010) . The commenter stated that the D.C. Circuit ’ s Sierra Club decision does not compel or even support EPA ’ s p roposed SSM
p rovisions. The commenter argued that t he Sierra Club decision did not address what the EPA may or may not include in category

- specific MACT standards. The commenter noted that court decisions have emphasized the need for standards to recognize and accommodate higher emission levels that occur at times other than normal operations. See, e.g.

, Sierra Club v. EPA

, 167 F.3d 658, 665 (D.C. Cir. 1999) (Section 112(d) standards based upon the performance of the best

- performing facilities are supposed to represent “ the emissions control that is achieved in practice ” by the best performers; this means that the best

- performing facilities will not violate the69 standards, and that will “ only result[] if ‘ achieved in practice ’ is interpreted to mean ‘ achieved under the worst foreseeable circumstances. ’” ); Cement Kiln Recycling Coalition v. EPA , 255 F.3d 855 (D.C. Cir 2001) (the Court choosing to vacate rather than simply remand MACT standards, based in part on the Agency ’ s failure to exempt hazardous waste com bustors from numerical emission limits during SSM periods and the Court ’ s “ similar doubts about EPA ’ s decision to require sources to comply with standards even during openings of emergency safety valves caused by events beyond the sources ’ control. ” Id . at 872).

The commenter further noted t he Sierra Club decision did not say that the same emission limitations derived for normal operations must apply during SSM events. Sierra Club does not preclude EPA from applying different standards during SSM events tha n apply during normal operations. In fact, the opinion acknowledges that section 302(k) ’ s “ inclusion of [the] broad phrase ” “ any requirement relating to the operation or maintenance of a source to assure continuous emission reduction ” in the definition of “ emission standard ” suggests the EPA can establish MACT standards consistent with CAA section 112 “ without necessarily continuously applying a single standard. ” See 551 F.3d at 1027. The commenter stated their interpretation i s also supported by the legislative history of section 302(k) , which stated that “ accepting that

‘ continuous ’ for purposes of the definition of ‘ emission standards ’ under CAA sectio n 302(k) does not mean unchanging ” and referring to “ the CAA ’ s requirement that some section 112
st andard apply continuously

. ” Moreover, the commenter noted, because it was addressing only a generic SSM exemption, the Sierra Club decision did not consider whether EPA, in the context of individual categorical standards, could determine that it is infeasi ble to apply the same limits, or any limits at all on the mass or concentration of pollutants emitted, during SSM events, or that it would lead to absurd results to do so.

The commenter also argued t here is precedent for the EPA applying a different standa rd during SSM events. They stated that f or over 30 years the EPA has not required sources to meet NSPS emission limitations under CAA section 111 established for normal operations during SSM events. See 40 CFR 60.8(c). According to the commenter

, Congress enacted the “ continuous basis ” language in section 302(k) with the knowledge that EPA ’ s emissions standards under section 111 exempted SSM periods. The commenters argue t here is nothing in the legislative history of the 1977 amendments to the CAA that sugg ests Congress intended to overturn that practice. Moreover, the commenter noted that court decisions both before and after the CAA Amendments of 1977 have affirmed the appropriateness of including special SSM provisions in standards issued under section 11 1 despite the “ continuous basis ” language in the definition of

“ emission limitation. ” Similarly, there is nothing in the legislative history of the CAA Amendments of 1990 that suggests Congress meant something completely different when it used the same defined terms, “ emission standard ” and “ emission limitation, ” in directing EPA, in amendments to section 112 that establish MACT standards.

The commenter also noted t he Sierra Club decision did not address whether 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 ” i n CAA section 302(k), in lieu of a numerical emission limitation during SSM events. The EPA told the Court that the General Provisions SSM exemption struck down in Sierra Club was not an alternative standard based on the work practice standard authority ( S ee 551 F.3d at 1028 ) but70 argued in that case that section 112(h) was irrelevant to its authority to exempt excess emissions during SSM events (see Id . at 1030 (Randolph, J. dissenting) )

.
Commenter 0533 stated that under CAA section 112(d)(2), MACT emission standards , including those that apply during SSM events, must be “ achievable ” with available technology, “ taking into consideration the cost of achieving such emission reduction, and any non

- air quality health and environmental impacts and energy requirem ents. ” A n emission limitation that applies during SSM events has not been demonstrated to be “ achieved ” by the best

- performing 12 percent of units in the category under CAA section 112(d)(3), unless EPA can show that those best performers actually meet tha t emission limitation during SSM events. The commenter argued the EPA can not establish “ continuous section 112

- compliant standards ” because EPA has not demonstrated that the emission would comply with section 112 when applied during SSM
events.

Commenter 0 533 explained that the courts have recognized that a “ technology based standard discards its fundamental premise when it ignores the limits inherent in technology. ” NRDC v. EPA , 859 F.2d 156, 208 (D.C. Cir. 1988). For example, the D.C. Circuit recognized, in Portland Cement Ass ’ n v. Ruckelshaus , 486 F.2d 375, 398 (D.C. Cir. 1973), a decision reviewing standards under CAA section 111, that “‘ start

- up ’ and ‘ upset ’ conditions due to plant or emission device malfunction, is an inescapable aspect of industrial life and that allowance must be made for such factors in the standards that are promulgated. ” Id . at 399. Similarly, in Essex Chem. Corp. v. Ruckelshaus , 486 F. 2d 427, 432 (D.C. Cir. 1973), cert. denied, 416 U.S. 969 (1974), another section 111 case, the D.C. Circuit held that SSM provisions are “ necessary to preserve the reasonableness of the standards as a whole. ” Id . at 433. In National Lime Ass ’ n v. EPA , 627 F.2d 416 (D.C. Cir. 1980), another case reviewing emission standards promulgated under CAA section 111, the D.C. Circuit held that the CAA requirement that NSPS be “ achievable ” means that the standards must be capable of being met “ on a regular basis, ” inc luding “ under most adverse circumstances which can reasonably be expected to recur, ” including during periods of SSM. 627 F.2d at 431 n.46.

Commenter 0533 also discussed analogous Clean Water Act requirements and noted that in one case the court held that where the EPA knew that there would be periods even with “ exemplary use of ” the identified best technology, the emissions would exceed the effluent limitations because of conditions “ beyond the control of the permit holder, ” EPA had violated the Clean Wate r Act by failing to provide an “ upset provision ” to address those periods. Marathon Oil Co. v. EPA , 564 F.2d 1253, 1273

- 74 (9th Cir. 1977). See also

, e.g. , NRDC v. EPA , 859 F.2d at 207 (distinguishing between technology

- based effluent limitations, where so me provision for

“ upsets ” is required, and water

- quality

- based effluent limitations, which are tied to achieving water quality standards rather than based on available technology, and, therefore, need not include an upset provision).

The commenter asserte d that the Weyerhaeuser Co. v. Costle decision EPA cites in the preamble to the Proposed Rule (i.e., 590 F.2d 1011 (D.C. Cir. 1978), does not support EPA ’ s position. In that case, the court was discussing a “ technology

- forcing ” standard and not a M ACT standard that must be based on what is demonstrated to be achievable. T he commenter also notes that SSM events are unus ual “ uncontrollable acts of third parties, such as strikes, sabotage, operator71 intoxication, or insanity ” that the Court was considering in the passage quoted by EPA, see id

. Industry is not requesting that the NESHAP provide relief from numerical emission limitations during those unusual types of events. Moreover, most of the cited events would not constitute

“ malfunctions, ” as EPA define s that term in 40 CFR 63.2 and in other policy statements, since they are the result of deliberate actions (e.g., deciding to continue to operate with inadequate staffing during a strike) or would constitute “ careless operation ” (e.g., operator intoxicatio n). The commenter also pointed out that the Weyerhaeuser decision was made before NRDC v. EPA , 859 F.2d 156 (D.C. Cir. 1988) which affirmed the need for an upset provision to address circumstances where compliance with effluent limitations is impossible th rough no fault of the permittee, and which endorsed Marathon Oil.

Response 3 : E xemptions for startup and shutdown are inconsistent with the holding in Sierra Club that emissions limitations under section 112 must apply continuously. T he Sierra Club decisio n does not constrain our authority to prescribe unique standards or work practice standards during SS periods where such standards are justified. We evaluated whether different standards during startup and shutdown periods are justified, and in this case, we established work practice standards to apply during startup and shutdown periods. T he decision to use a work practice standard is wholly within the discretion of the EPA. CAA section 112(h) ( “ [T]he Administrator may, in lieu [of a numeric standard], pro mulgate a design, equipment, work practice, or operational standard, or combination thereof. ” ). In exercising the option to establish a work practice standard, that standard must “ in the Administrator ’ s judgment [be] consistent with the provisions of subsection (d) or (f). ” CAA section 112(h)(1) (emphasis added). These subsections make clear that the EPA is to base emission standards on the emission levels already achieved by the best performing sources and to ensure that public health is protected, as applicable. This means that work practice standards, although written in non

- numeric form, must still satisfy statutory requirements such as those applicable to MACT standards, including the requirement to be no less stringent than the MACT floor.

C ontrar y to the commenter ’ s argument, we believe that the standards that apply during startup and shutdown periods will establish “ continuous section 112

- compliant standards ” that the Sierra Club decision concluded are required. We also disagree with the comment that the Sierra Club decision “ did not by its terms ” concern what EPA may or may not include in category

specific MACT standards. (Citing letter to counsel from Adam Kushner, Director of EPA ’ s Office of Civil Enforcement, July 22, 2009 (see Table 2 of the letter)). This letter, which addressed potential compliance issues arising from the Sierra Club court decision, contained EPA ’ s plans for addressing those concerns, including potential future revisions to section 112(d) standards. As explained in the lette r, our initial analysis indicated that certain rules, such as the mineral wool production NESHAP, included specific regulatory text exempting or excusing compliance during SSM events in addition to cross

- references to 40 CFR. Sections 63.6(f)(1) and 63.6(h )(1). At the time, we indicated that the vacatur in Sierra Club would have no direct impact on such source category

- specific SSM provisions because we believed these provisions were not challenged in Sierra Club . We, however, also recognized that the legal ity of those

source

- category specific provisions may have been called into question and indicated that we were evaluating them in light of Sierra Club

. “ The tables attached to this letter are based on the EPA ’ s initial analysis and are, therefore, subject to change. ” (p. 3) [footnote omitted]. We have now evaluated the relevant provisions and determined that they need to be revised to address the Sierra Club decision.72 We disagree with commenter ’ s claim that case law under the CAA and Clean Water Act ( CWA )

s upports its argument that EPA ’ s approach to startup and shutdown periods is inconsistent with CAA section 112. As explained above and in the preamble to the 2013 and 2014 proposed rules, the EPA has taken into account startup and shutdown periods in determ ining appropriate standards. T he relevance of Portland Cement and Essex Chem. Corp. is questionable in light of subsequent case law and the 1977 amendments to the CAA definition of emission standard requiring that such standards be continuous. As the D.C. Circuit noted in National Lime v. EPA

, 627 F.2d. 416, 434 at n 54, “ [w]hether the 1977 Amendments have effectively repealed the regulations permitting flexibility to account for startups, shutdowns and malfunctions regulations applauded by this court in Po rtland Cement I , 486 F.2d at 398

- 99 is certainly unclear. ”

The NRDC v. EPA (859 F. 2d 156, 207(D.C. Cir. 1988)) case cited by commenter interprets provisions of the CWA that are different in nature than provisions governing standards under section 112 of the CAA. Furthermore, the discussion of technology

- based standards in the NRDC case is dicta. Nevertheless, the EPA ’ s approach to malfunctions is also consistent with NRDC

. NRDC does not require exemptions or less stringent standards for malfunction period s. Further, the regulatory affirmative defense included in today ’ s final rule is consistent with the case cited in the NRDC decision; Marathon Oil Co. v. EPA , 564 F.2d 1253, 1272 (9th Cir. 1977). The court in Marathon Oil held that EPA must formalize its a pproach to upsets under the CWA. The affirmative defense does so. See, Mont. Sulphur & Chem. Co. v. United States EPA , 2012 U.S. App. LEXIS 1056 (5th Cir. Jan 19, 2012) (in rejecting industry argument based on Marathon Oil that reliance on the affirmative defense was not adequate, court stated “ [h]owever, here the EPA does not rely on enforcement discretion alone, but specifically promulgates an affirmative defense in the FIP, which clearly defines the requirements to avoid penalties. ” ). But see, Weyerhaeus er v

. Costle , 590 F.2d 1011, 1057

- 58 (D.C. Cir. 1978) (holding that an informal approach is adequate).

Comment 4 : Numerous commenters (0516, 0518, 0520, 0521, 0522, 0528, 0531, 0537, 0543, 0545, 0551, 0555, 0556, and 0563 ) asserted that the startup and shutdown procedures listed in the proposed rule cannot be met by all BSCP kilns and must be modified. C ommenters (0516, 0520, 0521, 0522, 0528, 0537, 0543, 0545, 0548, 0551, 0553, 0555, 0556, 0558, 0563) requested that the final langu age allow a more basic construct for the work practice requirements in the final rule and require facilities to develop site

- specific temperature s as part of their permitting
process. Alternatively, two c ommenters ( 0555, 0556 ) suggested the EPA require sit e

- specific
start

- up and shutdown procedure plan similar to the one required by the vacated 2003 Brick MACT. C ommenter 0543 agreed and stated that the final rule should allow facilities to formalize their procedures for various types of start

- up conditions, with approval by the regulating authority. The c ommenter noted that the EPA proposed site

- specific startup practices in the startup provisions for the Boiler MACT ( 80 FR 3090, 3095 ; Jan. 21, 2015). As a third option, the commenter suggested that the EPA c ould specify several different procedures in the final rule that reflect the variety of standard practices currently in use, and then allow affected facilities to select the procedure that matches their circumstances.

Multiple commenters (0516, 0518, 0520, 0522, 0537, 0543, 0545, 0548, 0551, 0553, 0558, and 0563 ) specifically stated that the requirement for an exhaust temperature of 400 ° F at startup is not workable because the kiln exhaust temperature in some kilns never reach es 400 ° F. Commenter s provided examples of about 10 kilns with average stack exhaust temperatures73 rang ing from 2 50

- 390 ° F ; two of these kilns had average exhaust temperatures below 300 °F

. C ommenter 0548 has a controlled kiln with exhaust that reaches 450 ° F during startup but drops during normal operation to 375 ° F.

Numerous commenters (0516, 0518, 0520, 0521, 0522, 0528, 0531, 0543, 0454, 0551, 0553, 0558, and 0563 ) noted that kiln s must have product at startup

. C ommenter 0537 stated that a tunnel kiln is always full of brick unless it is taken cold for a maintenance activity. C ommenter 0543 stated that in a tunnel kiln, the kiln cars form the bottom of the kiln envelope. A continuous line of kiln cars is needed to protect the wheels and underside of the ki ln cars from damage from the high heat. Typically, if a kiln has been previously fired, the bricks that were in the tunnel kiln during the previous firing are put back in the kiln in the position they were before a shutdown, or in some cases, moved back in the process a few car lengths. Commenter 0516 added that the owner or operator must push the kiln cars forward during the startup cycle to facilitate the development of the kiln ’ s temperature profile as it approaches normal production operational conditio ns. This procedure needs to take place before the exhaust temperature reaches the operating range. Commenter 0545 noted that some kilns cannot achieve 400 °F in the stack unless there are bricks in the kiln to trap the heat.

Therefore, C ommenter 0543 reque sted that the startup provisions apply to the introduction, or charging, of new brick or structural clay product through a kiln and do not impact the initial staging of kiln cars in a kiln before start

- up. Two commenters (0537 and 0543) agreed that facilit ies would not push product through a kiln before proper temperature is achieved because to do so would impact the final quality of the brick or structural clay product. Several other commenters (0520, 0521, 0537, and 0545 ) agreed that it would be appropria te to specify that no new production take place during startup, but the rule should not prohibit the presence of any bricks in the kiln during startup.

Specifically, two commenters (0543 and 0553 ) suggested revisions to the proposed language to

“ not put an y bricks into the kiln ” below specified temperatures. Commenter 0553 requested that the language reflect actual operating scenarios and read “ Do not push or index any brick into the kiln until the kiln exhaust temperature reaches... ” Commenter 0543 suggest ed that the EPA clarify that this language is intended to mean that brick production, i.e., pressing brick to make a saleable product, should not occur before the kiln is vented to the air pollution control device, if present. Further, the commenter sugges ted revising the proposed shutdown procedure language to read “ Do not charge new product into the kiln once kiln shutdown begins and the temperature in the exhaust stack reaches the shutdown temperature approved as part of your site

- specific parameters. ” The commenter noted that kilns burning solid fuel may sometimes need to push product from the initial gas fired zones into solid fired zones until a temperature proof can be established such that the solid fuel ignition temperatures in those zones is high enough to achieve combustion, so a one

- size

- fits

- all standard is not possible.

Multiple commenters (0516, 0520, 0537, and 0545 ) agreed with the language that requires a kiln to vent to an APCD before the exhaust gas reaches 400 degrees F, because it can ve nt at any time up to that temperature. Multiple commenters (0516, 0537, 0543, and 0548 ) stated that for a controlled kiln, it is acceptable to require that no new product is allowed to be introduced to the controlled kiln until the kiln is vented to an APC D. C ommenter 0516 stated that a feasible work74 practice standard would be for the exhaust gases to be vented through the APCD during the startup process, with the reagent feed started on an intermittent basis during this period and then brought up to full f eed rate once the exhaust temperature has reached the normal operating temperature range.

A few commenters also requested specific revisions to the production requirements for periods of shutdown. C ommenter 0516 stated that during shutdown, a kiln operator would not be pushing any cars in the kiln after reaching a range of 250 to 300 °F in the exhaust stack (depending on the type of kiln and its operating parameters). The commenter asked that a minimum operating range be allowed during a shutdown cycle. C om menter 0543 noted that a limitation for a kiln to cease charging in new product before a kiln stops venting to an APCD may be a reasonable alternative to temperature requirements. Commenter 0543 asserted that to require anything different than typical oper ation for BSCP tunnel kilns during startup or shutdown would be considered

“ beyond the floor ” for the industry, and EPA must consider costs as well as the practicality of the revised procedures.

Response 4 : The EPA evaluated these comments and agrees that the proposed standards would not be achievable for some kilns. T he inten t of the proposed standards was to minimize emissions by limiting the amount of brick being fired and limiting the amount of time the exhaust is not being routed to the APCD, if applic able. As noted at proposal, the standards were based on information received through the 2010 EPA survey . Based on additional information received following proposal, the EPA has revised the wor k practice standards for periods of startup and shutdown for B SCP tunnel kilns to provide requirements for minimizing emissions that are feasible for all kilns.

Specifically, instead of defining the minimum inlet APCD temperature as 400 °F, the EPA is requiring the owner or operator to determine the minimum inlet tem perature for each APCD. If a kiln does not have an APCD, the owner or operator is required to determine the product

- specific kiln temperature profile that must be achieved before the kiln can reach full production. In addition, instead of specifying that n o product can be introduced to the kiln during startup, the EPA is requiring the owner or operator to determine the production rate needed to start up the kiln. The final startup standards specify that this startup production rate cannot be exceeded until the kiln exhaust reaches the APCD minimum inlet temperature or the product

- specific kiln temperature profile, whichever is applicable. The final shutdown standards specify that no additional product can be introduced once the kiln exhaust falls below the A PCD minimum inlet temperature or the product

- specific kiln temperature profile, whichever is applicable.

Comment 5 : Commenters made a number of requests for EPA to allow for alternate procedures with regard to startup and shutdown. Multiple commenters (0516, 0521, 0537, 0543, and 0545 ) suggested that in the case of a kiln car crash inside the kiln, the EPA should allow for an alternate procedure when the typical procedure cannot be followed. Commenter 0520 similarly asked that the EP A allow for an alternate procedure when the typical procedure cannot be followed. Commenter 0537 requested exemptions from generalized, routine written start

- up shutdown requirements for unanticipated, site specific non

- routine occurrences. Commenters 0537 and 0543 also asked that facilities be allowed to establish alternate procedures for cold start
up.75 Response 5 : The EPA does not agree with the commenters ’ requests for alternate procedures. Kiln car crashes and “ unanticipated, site specific non

- routine o ccurrences ” meet the definition of malfunction , and exemptions from standards during malfunctions are no longer allowed.

Comment 6 : Multiple commenters (0537, 0543, 0545, 0551, and 0553 ) stated that the requirements should be modified to pertain to control devices only, and not the kilns. Commenters 0516, 0520, 0521, 0537, 0543, and 0553 stated that for uncontrolled kilns, there is no environmental benefit gained from requiring specific start

- up or shutdown procedures.
Response 6 : The CAA requires that NESHAP emissions limitations under section 112 must apply continuously, including during periods of startup and shutdown. This would apply to all kilns, controlled and uncontrolled. T he EPA has revised the work practice standards for periods of startup and shutdown for BSCP tunnel kilns to provide requirements that are less prescriptive and more representative of the best performing kilns and ensure continuous section 112

- compliance standard s.

Comment 7 : Commenter 0543 asked that the EPA correct the rule to not simultaneously enforce work practice requirements under section 112(h) of the CAA and numeric limits under section 112(d). In the proposed rule, 40 CFR 63.8420(a) states that:

“ You mu st be in compliance with the emission limitations (including operating limits) in this subpart at all times, except during periods of routine control device maintenance as specified in paragraph (d) of this section. ”

Commenter 0543 stated that unless EPA a dds the exclusion for periods of start

- up and shutdown to this paragraph, the rule would be simultaneously requiring compliance with both a numeric limit under section 112(d) and a work practice limit under section 112(h). Section 112(h) clearly states tha t a work practice is allowed “ in lieu of ” a limit established under section 112(d). The commenter asked that EPA clarify that only the work practice requirements are in effect during periods of start

- up and shutdown by revising 40 CFR 63.8420 to read:

“ You must be in compliance with the emission limitations (including operating limits) in this subpart at all times, except during periods of routine control device maintenance as specified in paragraph (d) of this section and during periods of start

- up and shu tdown. ”

Response 7 : The EPA agrees with the commenter that 40 CFR 63.8420(a) should be clarified. We have revised 40 CFR 63.8420(a) as follows to account for start

- up and shutdown and also the alternative standard for routine control device maintenance :

You must be in compliance with the emission limitations (including operating limits) in this subpart at all times, except during periods that you are approved for and in compliance with the alternative standard for routine control device maintenance as
spe cified in paragraph (d) of this section, and except during periods of start

- up and shutdown, at which time you must comply with the applicable work practice standard specified in Table 3 to this subpart.76 11.0 Malfunction

Comment 1: Multiple commenters (0 516, 0520, 0537, 0543, and 0558) stated that it is not reasonable to take a stack test that was conducted on a kiln during normal operation and apply that emission limit to the kiln during a malfunction, nor does the variability of three test runs during n ormal operation account for periods of non

- normal operation. Commenters 0520, 0537, and 0558 stated that to apply a stack test that occurs during steady operation and apply it to malfunction periods is going beyond what is “ achieved ” by a source and into w hat EPA is assuming is “ achievable. ”

Multiple commenters (0516, 0537, 0543, and 0558) stated that if a facility were going to be able to be in compliance with numeric limits during a malfunction, a redundant control would be needed. Commenter 0537 stated t hat this is probably not even economically or technically feasible

, nor has it been included in the proposed rule cost.

Multiple commenters (0516, 0520, 0533, 0537, 0543, 0555, 0556, and 0558) stated that it is not possible to test during a malfunction. Mu ltiple commenters (0516, 0520, 0533, 0537, 0543, and 0558) also stated that because it is not technically or economically feasible to test during these periods, malfunctions meet the criteria of section 112(h) of the CAA that allows for work practice stand ards.

Response 1: The EPA disagrees with the commenters ’ argument that stack test data from periods of normal operation cannot be used to adequately account for the variability during periods of

non

- normal operation. We have set the MACT standards at a lev el that a well

- operated source should be able to meet during 99 percent of all stack tests, which we believe sufficiently accounts for variability. Consequently, we disagree that a redundant control would be necessary to comply with emission limits during periods of malfunction. With respect to the commenters ’ suggestion that the EPA consider work practice standards for periods of malfunction

, we refer to our response to the third comment in this section.

Comment 2: Multiple commenters (0516, 0537, 0543, 0555, 0556, and 0558) stated that a reasonable work practice would be to require each facility with a control device to develop a malfunction plan, similar to the one required by the now

- vacated 2003 Brick MACT. Comm enters 0558 and 0563 suggested that the work practice could require a facility to develop, maintain, and follow a plan for periods of malfunctions and revise a plan, as needed. For example, a plan revision would be warranted if a malfunction occurred that was not included in the current malfunction plan. It would be a deviation from the work practice, and a possible violation, if the plan was not followed during a malfunction or not updated.
Response 2: The EPA does not agree with the commenters ’ request fo r a work practice standard requiring facilities with control devices to develop a malfunction plan. In exercising the option to establish a work practice standard, that standard must “ in the Administrator ’ s judgment [be] consistent with the provisions of s ubsection (d) or (f). ” CAA section 112(h)(1) These subsections make clear that the EPA is to base emission standards on the emission levels already achieved by the best

- performing sources and to ensure that public health is protected, as applicable. There is no way to prescribe the s pecific requirements within a malfunction plan to ensure that each plan reflects the l evel of emission reductions achieved by the best

- performing sources

.77 Comment 3: Commenter 0533 stated that CAA section 112 does not require or even allow the EPA to ignore malfunctions when set ting MACT standards

. The commenter stated the EPA cannot ignore the requirement that MACT floor standards reflect performance actually achieved

. The commenter asserted that statutory language, congressiona l intent, and case law support EPA promulgating alternative emission standards for malfunction events ( either numerical limits or work practices )

. By setting standards for malfunction events, the EPA would not have to affect the stringency of the emission standards that apply during normal, steady

- state operations

.

Commenter 0533 also disagreed with the EPA ’ s view that applying the concept of “ best

performing ” is inconsistent with a source experiencing a malfunction. See 79 FR 75626. The commenter argued that best performers experience malfunctions and there are work practices ( such as monitoring of 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. Commenters 0516, 0533, and 0537 noted that the measures representing these best practices will depend on facility

- specific issues.

Commenter 0533 stated that facility

- specific best practices represent the “ the m aximum degree of reduction in emissions of the hazardous air pollutants...achievable...through application of measures, processes, methods, systems or techniques ” and reflect “ the emission control that is achieved in practice by the best controlled similar source[s] ” CAA section 112(d)(2) and (3)

.

Commenter 0533 stated that there is no basis for EPA ’ s conclusion that malfunction events are not representative of best

- performing sources. See id .; see also, e.g. , Cement Kiln Recycling Coalition , 255 F.3d at 8 62

- 865 (recognizing that there is variability in the performance of control technologies, which needs to be taken into account in establishing emission limitations based on the MACT floor); Sierra Club v. EPA , 167 F.3d 658, 665 (D.C. Cir. 1999). The commen ter asked that the EPA acknowledge the fact that best performing sources experience malfunction
events and not set MACT standards that even the best performing existing sources cannot achieve part of the time . The commenter asserted that the EPA is going b eyond the MACT floor without making the demonstrations that the statute and case law require the Agency to make in order to impose beyond

- the

- floor MACT standards (including the Agency ’ s obligation to consider costs). Commenters 0516, 0537, and 0543 concurred with this comment.

Commenter 0533 stated that when a facility experiences exceedances due to a malfunction, even though affirmative defense was struck down, the EPA ’ s response will be based on whether the facility had conducted “ root cause analyses to ascertain and rectify excess emissions. ” 79 FR 75627. The commenter argued the EPA made no attempt to justify those conditions as reasonable “ taking into consideration the cost of achieving such emission reduction, and any

non

- air quality health and environmental impacts and energy requirements, ” as required by CAA section 112(d)(2).

Commenter 0533 stated the EPA should include emissions data representing malfunctions (if such data exist) in calculating the MACT floor (see 79 FR 75626) or considering alternative work practice standards, instead of requiring that th e MACT floor limitations be met even during malfunctions. If it is possible to gather sufficient representative data reflecting emissions during malfunctions, then the EPA is obligated to con sider those data in its MACT floor calculations for78 steady

- state operating conditions. To the extent EPA had access to continuous monitoring data for emission units covered by the NESHAP, the commenters asserted the EPA could have conducted analyses of emi ssions levels during malfunction events. The commenter stated that even if continuous monitoring data are for parameters not regulated by the proposal, the monitoring data might form a reasonable basis for EPA ’ s assessment of what standards are achieved or achievable during malfunctions. Also, many types of sources are required by many state agencies to submit deviation reports or malfunction reports when they experience a malfunction that causes an exceedance of an applicable limitation. The commenters sta ted that the EPA does not appear to have made any attempt to obtain and analyze such reports, in order to assess what type of requirement might reasonably apply during malfunctions.

Commenter 0533 stated that before affirmative defense was struck down, the Agency believed that an affirmative defense provision was necessary so that MACT standards would be based on what is achievable with available technology

. The EPA not only does not include an affirmative defense, it does not explain why it is reasonable t o treat exceedances associated with malfunctions as violations. The commenter recommended the EPA include many of the concepts that it incorporated into the affirmative defense provisions of other recent NESHAP proposals into alternative, work practice sta ndards that would apply during malfunctions. Th ey argue that this approach would be consistent with NRDC v. EPA

.

Commenter 0533 stated that the EPA ’ s statement “

. . . the EPA would determine an appropriate response based on, among other things, the good fa ith efforts of the source to minimize emissions during malfunction periods, including preventative and corrective actions, as well as root cause analyses to ascertain and rectify excess emissions, ” (79 FR 7527) are inadequate . The
commenter questioned whet her there would ever be an appropriate time for EPA not to use its enforcement discretion. The EPA has provided no analysis that would supersede its long

standing determination that it is not appropriate to rely on enforcement, rather than regulatory langu age, to address the inability to comply with technology

- based standards during SSM events. See 37 FR 17214 (Aug. 25, 1972) (establishing SSM provision in NSPS). The commenter asserted that the courts have adopted the same view. See, e.g. , Portland Cement

, 486 F.2d at 398 n.1; National Lime , 627 F.2d at 431 n.46 ( “ the flexibility appropriate to enforcement will not render ‘ achievable ’ a standard which cannot be achieved on a regular basis, either for the reasons expressly taken into account in compliance det ermination regulations (here startup, shutdown and malfunction), or otherwise. ” ). 21

Commenter 0533 also noted the EPA ’ s exercise of its discretion not to bring an enforcement action for excusable malfunctions does nothing to prevent a source from having to defend itself from a citizen suit or state enforcement action for the same malfunctions, nor does the Agency

21 See also Marathon Oil Co. v. EPA , 564 F.2d at 1273 (explaining why EPA’s statement that it would not take enforcement action against sources that exceeded effluent limitations because of upset events wa s “not an adequate response” to the argument that standards that cannot be met during unavoidable upsets fail to reflect available technology). Also for these reasons, the commenter stated that EPA’s statements in the Proposed Rule preamble that EPA will “ determine an appropriate response” to reported exceedances of the Proposed Standards, based on, “among other things, the good faith efforts of the source to minimize emissions during malfunction periods, including preventative and corrective actions, as we ll as root cause analyses to ascertain and rectify excess emissions” (79 FR 75627), are not in any way a substitute for EPA setting the standards at an achievable level in the first place.79 state that it will exercise its enforcement discretion for events that meet the criteria it has applied in the past to the affirmative defense. The commenter noted that a fter

- the

- fact determinations of whether or not to penalize a source that has a malfunction do not require or encourage measures that may reduce the magnitude or duration of exceedances associated with malfunctions. The
commenter reco mmended that the EPA address compliance during malfunctions by promulgating an achievable alternative standard.

Commenter 0533 noted in a district court enforcement action or in a citizen enforcement action,

“ similarly, the presiding officer in an administ rative proceeding can consider any defense raised and determine whether Administrative penalties are appropriate. ” 79 FR 75627. The commenter noted that in NRDC v. EPA , the Court specifically recognized the EPA has authority to limit the situations in which it will impose administrative penalties in that manner. See 749 F.3d at 1063 ( “ By contrast, EPA ’ s ability to determine whether penalties should be assessed for CAA violations extends only to administrative penalties, not to civil penalties imposed by a court. ” (citation omitted)). The commenter recommended the EPA affirmatively state in the final rule that the Agency will not seek administrative penalties for excess emissions caused by malfunctions.

Comment er 0533 noted that in the portion of the proposed rule dealing with air pollution control device maintenance, the EPA allowed sources to bypass an APCD under certain circumstances to perform control device maintenance(see 40 CFR 63.8420(d)). The commenter stated that proposed 40 CFR 63.8420(d) is an example of how EPA has used its work practice authority to establish alternative emission standards in situations that are analogous to addressing emissions during malfunction events.

Response 3 : The EPA disagre es with the comment that it is required to take malfunctions into account when adopting MACT standards and that a separate standard be set for periods of malfunction. As explained in the preamble, the EPA has determined that CAA section 112 does not requir e that “ emissions that occur during periods of malfunction...be factored into development of CAA section 112 standards...There is nothing in CAA section 112 that directs the agency to consider malfunctions in determining the level “ achieved ” by the best

- perfor ming sources when setting emission standards. As the U.S. Court of Appeals for the District of Columbia Circuit has recognized, the phrase “ average emissions limitation achieved by the best performing 12 percent of ” sources “ says nothing about how the perf ormance of the best units is to be calculated. ” Nat ’ l Ass ’ n of Clean Water Agencies v. EPA , 734 F.3d 1115, 1141 (D.C. Cir. 2013). ”

As we further explained, “ accounting for malfunctions in setting emission standards would be difficult, if not impossible, gi ven the myriad different types of malfunctions that can occur across all sources in the category and given the difficulties associated with predicting or accounting for the frequency, degree, and duration of various malfunctions that might occur. For these reasons, the performance of units that are malfunctioning is not “ reasonably ” foreseeable. See, e.g., Sierra Club v. EPA , 167 F.3d 658, 662 (D.C. Cir. 1999) ( ‘‘ The EPA typically has wide latitude in determining the extent of data

- gathering necessary to so lve a problem. We generally defer to an
agency ’ s decision to proceed on the basis of imperfect scientific information, rather than to

‘ invest the resources to conduct the perfect study. ’” )80 With respect to the commenters ’ suggestion that EPA consider work p ractice standards, the decision to use a work practice standard is wholly within the discretion of the EPA. CAA section 112(h) ( “ [T]he Administrator may, in lieu [of a numeric standard], promulgate a design, equipment, work practice, or operational standard, or combination thereof. ” ). In exercising the option to establish a work practice standard, that standard must “ in the Administrator ’ s judgment [be] consistent with the provisions of subsection (d) or (f). ” CAA section 112(h)(1) (emphasis added). These subsections make clear that the EPA is to base emission standards on the emission levels already achieved by the best

- performing sources and to ensure that public health is protected, as applicable. This means that work practice standards, although w ritten in non

numeric form, must still satisfy statutory requirements such as those applicable to MACT standards, including the requirement to be no less stringent than the MACT floor.

It is just as difficult to establish a work practice standard for malfu nctions that can approximate the level of emission reduction achieved by the best

- performing sources during malfunctions as it would be to factor emission levels that occur during malfunctions into the numeric standards. The EPA would have to design a sing le work practice standard that applies equally to a tank explosion as it does to innumerable types of operator error, computer glitches or a myriad of other unknown events, or alternatively create innumerable work practice standards.

In summary, the EPA be lieves that, based on this rulemaking record, it would be clearly inappropriate to set a work practice standard for malfunctions in lieu of the otherwise applicable numerical emission limit. We also note that we would consider any response to violations ca used by a malfunction on a case

- by

- case basis through the exercise of enforcement discretion. However, we disagree with the commenter ’ s suggestion that the EPA limit its discretionary authority by affirmatively stating in the final rule that it will not se ek administrative penalties for excess emissions caused by malfunctions

.

Comment 4 : Commenter 0533 noted that in the proposed rule, the EPA replaced the NESHAP General Provisions section that establishes a “ general duty ” to operate a source consistent with safety and good air pollution control practices for minimizing emissions, 40 CFR 63.6(e)(1), with somewhat different “ general duty ” language in proposed 40 CFR 63.8420(b). The D.C. Circuit did not vacate the provision EPA replaced, 40 CFR 63.6(e)(1), in S ierra Club v. EPA (which vacated the “ exemption ” for SSM events in 40 CFR 63.6(f)(1) and (h)(1), not the requirement for good air pollution control practices), and, contrary to EPA ’ s assertion in the preamble to the Proposed Rule, 40 CFR 63.6(e)(1) does no t reference provisions that were vacated in Sierra Club v. EPA . Compare Table 8, 79 FR 75691, and Table 9, Id . at 75716 of the Proposed Rule with 79 FR 75626. The Agency must provide a cogent explanation of why the old rule was unacceptable and the new rul e is necessary. The commenter suggested that the proposed new general duty provisions be deleted, and delete proposed 40 CFR 63.8420(b) from the final rule. If the EPA does not delete 40 CFR 63.8420(b)

, the Agency should re

- propose the provision with some explanation of the basis and purpose for the provision, to allow the public an opportunity to provide meaningful comments, as required by CAA section 307(d)(3).
Response 4 : Section 63.6(e)(1)(i) describes the general duty to minimize emissions. The current language in 40 CFR 63.6(e)(1)(i) characterizes what the general duty entails during periods of SSM. With the elimination of the SSM exemption, there is no need to differentiate between normal operations, startup and shutdown, and malfunction events in des cribing the general duty.81 Consequently, we proposed that the entry for 40 CFR 63.6(e)(1)(i) in the General Provisions table (Table 8 to Subpart JJJJJ) in column 4 should be “ no. ” We also proposed adding general duty regulatory text at 40 CFR 63.8420(b) that reflects the general duty to minimize emissions while eliminating the reference to periods covered by an SSM exemption. Therefore, the language the EPA proposed for 40 CFR 63.8 420(b) does not include the current language in 40 CFR 63.6(e)(1). The proposed changes were necessary to clarify the general duty requirements in light of the elimination of the SSM exemption. Consequently, we must deny the commenter ’ s request to have pro posed 40 CFR 63.8420(b) deleted from the final rule . R eproposal of the section, with some explanation of the basis and purpose for the provision, is also unnecessary and is denied

.82 12.0 Testing and Initial Compliance Requirements

Comment 1: Commenter 05 40 suggested a mass balance calculation should be used instead of stack testing to determine compliance with the Hg standard. The commenter stated that stack testing a t up to $15,000 per test is a significant economic burden to the industry . The method

rec ommended by this commenter us e inexpensive raw material testing to determine compliance with the standard

.

The commenter has conducted a preliminary study in which they tested over 175 brick samples before and after firing using t est method M7473 with a reported detection of < 1.83 ppb

. The brick materials tested include alluvial clay deposits, various shale materials and coal major fireclays. Mercury content in the various materials before firing range from non

- detect levels to levels of slightly over 200 ppb.

The commenter estimat ed th e Hg emissions using the raw material Hg test data (i.e., the difference between the Hg levels in the fired and unfired samples) and the estimated Hg emissions from fuel combustion (estimated using AP

- 42 or other documented emission factors from the Boiler MACT ) . Where fired brick samples measured below detection, the commenter assumed all of the Hg in the unfired sample was released. For comparison to an existing Method 29 test, the commenter used the production rate during that test to determine a lb/ton emission rate. Since the lb/ton emission rate is expressed in terms of fired brick, the weight lost on ignition was factored into the determination. Although the raw material samples were not collected concurrently with the Method 29 tests, the commenter n oted the results are nonetheless promising for the use of raw material data as an indicator of emissions. According to the commenter, 85 percent of the predicted emissions using raw material data concur with the Method 29 tests The data for only three kiln s did not show good agreement; however, the commenter noted that the data for only one kiln suggested compliance when the stack test does not. Raw material based emissions for this particular kiln were 60 percent of the stack test emissions. Of the 20 kiln s with raw material and Method 29 data, 10 had a higher emissions estimate using the mass balance approach than the stack test. For the 10 with lower emissions, the raw

- material

- based emission estimates ranged from 60 percent to 94 percent of the stack tes t emissions. The suggested that this disparity could be address by the EPA setting a percentage of the numeric MACT limit that the raw material mass balance based emission estimate would have to meet to demonstrate compliance. The commenter further argued that the mass balance approach may be a better tool to demonstrate a compliance given the problems associated with Method 29 detailed in other comments submitted by Mike Hartman of AirTech Environmental.

Based on their initial findings, t he commenter sugge st ed that with continued raw material testing, the mass balance approach can be used as an adequate if not conservative indicator of kiln Hg emissions and a viable alternative to Method 29 testing. The commenter further recommended that if the EPA requires Method 29 testing for the initial compliance demonstration, the n raw material testing could be used as a surrogate for Method 29 testing for subsequent demonstrations of compliance.

Response 1: The EPA disagrees with the mass balance approach. M ass balanc e of Hg is very difficult to complete correctly. There would need to be complete HF diges tion of the raw material and a complete a ccounting of all sources of Hg

. A 60 percent to 85 percent comparison83 is not a good correlation. The raw material may be the major source of the Hg but it could not be the only source of Hg in a kiln. Because there is a measureable concentration of Hg in most of the ICR test data, work practice standards are not applicable. Method 29 can be utilized to d etermine the conc e ntratio n of Hg being emitted from the kiln stack. The variability of the raw material was taken into account in the development of the MACT floor within the UPL calculations. The data co llected utilizing Method 29 is the emission concentration from the stack and will be utilized to demonstrate compliance with the Hg limit unless an alternative method is petitioned and approved by the Measurement Technology Group of the EPA

. The alternative method needs to demonstrate similar results and a high correlation to Method 29 data.

Comment 2: Commenter 0543 noted the EPA identified a number of issues with stack test reports and had discard ed test run s because of sample contamination, manganese contamination, filter failure, and other failures (e.g., reported values be ing close to method and analytical detection limits) that were not identifiable during the tests. The commenter stated that while the EPA use d only two of three runs for establishing emission limits, the proposed Brick MACT requires a minimum of three qual ifying test runs for demonstrating compliance.
Response 2: The EPA disagrees with this comment. The EPA did discard test runs when the EPA Refe rence method was not followed or the required QA elements within the method failed

, or sample contamination occurred. Data did not get discarded if the test values were close to method and analytical detection limits

. For demonstrating compliance, the E PA requires in 40 CFR 63.7(e)(3) that “ [u]nless otherwise specified in a relevant standard or test method, ea ch performance test shall consist of three separate runs using the applicable test method. Each run shall be conducted for the time and under the conditions specified in the relevant standard. For the purpose of determining compliance with a relevant stand ard, the arithmetic mean of the results of the three runs shall apply. ”
Allowing for the use of less than three test runs to demonstrate compliance is generally not allowed. Under certain circumstances, results of a test run may be replace with an additio nal test run. This requires approval from the Administrator or a delegated authority. The specific circumstances when a test run may be replaced are listed in section 63.7(e)(3) of the general provisions and include:

(i) A sample is accidentally lost after the testing team leaves the site; or

(ii) Conditions occur in which one of the three runs must be discontinued because of forced shutdown; or

(iii) Extreme meteorological conditions occur; or

(iv) Other circumstances occur that are beyond the owner or operator ’ s control.84 13.0 Continuous Compliance Requirements

Comment 1: Multiple commenters (0516, 0520, 0521 /Endicott , 0543, 0552, 0553, and 0558 ) argued that EPA should provide an alternative to the “ no visible emissions ” requirements.

The commenters noted that the proposed rule requires that all facilities demonstrate that they can meet the non

- Hg metal standard (or PM surrogate) by conducting a stack test. Ongoing compliance is then demonstrated by daily documentation of “ no visible emissions. ” Howev er, a facility may be able to demonstrate compliance with the PM emission limits even though periodic visible emissions may be witnessed during their performance test. Having “ no visible emissions ” 100 percent of the time is not a feasible condition to mai ntain during normal production operations. For that reason, visible emissions ( VE ) is not a reasonable parameter to prescribe for purposes of assessing ongoing compliance with the non

- Hg metals/PM standard. At a minimum, in those instances, the facility sh ould be allowed to prove ongoing compliance by demonstrating that the percent of operating time with visible emissions does not exceed the percent of time with visible emissions observed during the performance test.

The commenters also made the following p oints:

1. I n some normal operating scenarios, periodic “ puffs ” of visually detectable opacity are sometimes observed. This can happen in uncontrolled scenarios when product is charged into the kiln. It can also happen when a DLA cycles limestone and durin g some flashing operations. In rare instances, a “ puff ” may be detected even on DIFFs during bag cleaning cycling. This is a normal part of these processes and does not mean there is a malfunction or even (necessarily) that any additional HAP are being emi tted.

2. If a facility can demonstrate compliance with one of the HAP emission limits (most likely the total metals per hour option if the visible emissions are carbon or limestone based) while having these periodic visible emissions, they should not be r equired to eliminate them under this MACT.

3. VE may also be visible during the filling of fresh reagent silos and emptying of spent reagent containments. This is normal operation and should not be considered a violation of the standard.

4. In some cases, visible emissions have nothing to do with HAP emissions. For example, condensable vapors, including water, can be visible under certain conditions. If a facility has demonstrated compliance with the hourly HAP metal limit, a “ no visible emis sions ” requirement would be unnecessarily problematic.

Commenter 0558 noted that they observe visible emissions from their kiln stacks as a result of sulfur dioxide ( SO 2 ) release. There is a possibility that these emissions could be visible while still com plying with MACT requirements for HAPs. Furthermore, there may be instances where a facility may be able to demonstrate compliance with the PM emission limits while still observing periodic visible emissions from control devices during their performance te st. If visible emissions were observed during the compliance test, then the rule should not limit those facilities to “ no visible emissions ” to demonstrate compliance going forward.85 Commenter 0543 stated that there should be an alternative approach that a facility could opt into if they have the visible emissions issues discussed above. The commenter would not recommend that EPA remove the current option

– just add an additional option if the duration of the puff is regular and anticipated. The commenter su ggested an addition to section 63.8470(f) that would allow periods of visible emissions during normal operations to accommodate circumstances like those described above.

Commenter 0521 /Endicott argued that ill

- chosen compliance demonstration requirements c an needlessly cause a huge burden on a facility, particularly when compliance may be initially demonstrated during a performance test, but then ongoing compliance cannot be demonstrated. The commenter expressed regret that EPA was not in a position to shar e such key requirements during the SBREFA panel process, as this would have allowed more time to consider other compliance demonstration requirements. The commenter asked that the rule be changed to accommodate a reasonable alternative method of ongoing co mpliance, such as the following:

1. A n opacity reading below 20 percent to demonstrate compliance, or

2. Demonstrating that the percent of operating time with visible emissions does not exceed the percent of time with visible emissions observed during the performance test, if the average opacity measured during the stack test did not exceed 20 percent.

The commenter asserted that this approach is more reasonable, demonstrates compliance as effectively, and does not penalize a small business such as theirs. The commenter estimated that their company will be forced to install approximately $6 million dollars of unnecessary air pollution control devices to comply with a no visible emission compliance requirement while having already complied with the underlying numerical limits of the rule in the first place. The commenter stated that they do not have the ability to pass these costs to their customers and that this requirement will create a huge financial burden on their company with little to no positive effect on the environment.

The commenter further noted that, based on thei r recent stack test , they comply with the PM limit as proposed for existing sources. In addition, the commenter indicated they have personnel that are trained and certified in Method 9 and thei r kiln stack test readings have been at or below 10 percent opacity.

Response 1 : In response to this comment, we are revising the VE monitoring option to allow sources to conduct a Method 9 opacity test if VE are observed during any daily Method 22 te st. If opacity greater than 10 percent is observed, sources are required to initiate and complete corrective actions according to their Operations, Maintenance and Monitoring ( OM&M ) plan. As an additional alternative, in lieu of meeting the VE monitoring r equirements, sources may conduct an annual Method 5 PM performance test

.86 14.0 Alternate Approaches

Comment 1: Commenter 0554 stated that CAA section 1 12(h) does not authorize the EPA set work practice standards for HAP metals emitted by brick tunnel ki lns. The commenter noted CAA s ection 1 12(h) allows the EPA to set a work practice standard for a category or subcategory of industrial sources, only if it is “ not feasible ... to prescribe or enforce an emission standard for control of a hazardous air poll utant or pollutants. ” The commenter also noted that the Congress defines in the statute “ not feasible to prescribe or enforce an emission standard ” as meaning that (A) a hazardous air pollutant or pollutants cannot be emitted through a conveyance designed and constructed to emit or capture such pollutant or that any requirement for, or use of, such a conveyance would be inconsistent with any Federal, State or local law; or (B) the application of measurement methodology to a particular class of sources is no t practicable due to technological and economic limitations. The commenter stated it would be unlawful for the EPA to set work practice standards for HAP metals. The commenter also disagreed with the industry ’ s justification that work practice standards we re needed because some test runs are below the detection limit. T he commenter stated that for Hg all test runs are above detection limits and for the other HAP metals only one is below the detection limit.

Commenter 0554 stated there is no technological limitation making “ the application of measurement methodology to a particular class of sources impracticable

, ” and even for units where test results fall below the detection limit, the application of measurement methodology is not impracti cable. Furthermore, t he commenter stated that the EPA cannot use its own choice to not set a detection limit as an excuse to avoid setting emission standards. The commenter noted that measurement methodologies with much lower detection levels exist and the refore, the fact that some data are below detection limits does not demonstrate technological barriers to measurement. See Sierra Club v. EPA , 479 F.3d 875 (vacating prior work practice standards for certain brick and clay ceramics plants on holding that t he lack of available data does not provide a valid justification for the EPA to set work practice standards under CAA s ection 1 12(h)).

The commenter noted the CAA authorizes the EPA to prohibit emissions where achievable and
can, a fortiori

, set standards at a specific detection limit higher than zero even if emissions cannot be measured below that detection limit. The commenter also mentioned that CAA s ection 1 12(d)(3) directs the EPA to base floors on the emission limitation achieved by the best performin g sources “ for which the Administrator has emissions information. ” CAA s ection 1 12(d)(3)(A). The commenter noted that the EPA can set standards based on the sources for which the Administrator does have usable emissions data. As long as the EPA has test ru n data above the detection limit that represents greater than 12 percent of the sources with data, the EPA can set standards and specify a test method that would detect emissions at these levels. T he commenter stated that the fact that some kilns might record emission levels below the detection limit is irrelevant because this fact does not show the application of the measurement methodology is impracticable, but rather that the source has low emission s or the method has high detection l evels.

Response 1: The EPA appreciates the commenter ’ s support for our decision not to set work practice standards for non

- Hg HAP metals.87 Comment 2: Two c ommenter s (0519 and 0554 ) opposed facility

- wide emissions averaging as an alternative means of compli ance with Hg and non

- Hg HAP standards for existing brick and clay tunnel kilns

. C ommenter 0554 argued that it is arbitrary for the EPA to view a “ source ” as an individual unit to set the floors, and then as a collection of individual units at a facility or plant, as the EPA does in the emissions averaging alternative. The commenter also noted that the EPA does not explain this inconsistency, and the unexplained inconsistency renders the emissions averaging alternative arbitrary and capricious.

Commenter 055 4 further stated that allowing emissions averaging is likely to result in higher facility

- wide emissions than if each kiln is required to comply with the MACT standards because many existing kilns are already meeting the proposed MACT standards. The commen ter stated that, for the Hg and non

- Hg HAP standards, the EPA estimates that under the proposed rule, 93 out of 132 brick tunnel kiln stacks will not need to change their air pollution control equipment in order to comply with the standards. T he commenter stated that averaging would allow some kilns that emit more than the standard to avoid installing control devices. Since the EPA did not factor the value of those lost pollution reductions in its impact analys e s, the commenter suggested the EPA should not allow emissions averaging.

Commenter 0519 was concern ed about implementation challenges, such as complications that averaging poses for inspectors and enforcement personnel in determining the requirements for individual units. This commenter expressed concern that inter

- pollutant trading may be allowed under an emissions averaging compliance approach. If the EPA decides to adopt emissions averaging, t he commenter urged the EPA to require (1) a ssurance that the environmental benefits of the averaging wi ll be equal to or greater than if each individual unit had complied separately; (2) a veraging is prohibited for new sources ; (3) a veraging between different pollutants, sources or source categories is prohibited ; and (4) a discount factor be applied to ens ure the average is as stringent as the MACT floor limits without averaging.
Response 2 : The EPA has conducted an analysis of the costs and impacts of the emissions averaging option as compared to the individual MACT emission limits and has determined that the emissions averaging option will result in substantially higher costs for the industry than the individual MACT limits

. Consequently, we have decided to finalize the individual MACT limits and not promulgate the emissions averaging opti on

.88 15.0 Costs and Impacts

15.1 Costs and Emissions Reductions

Comment 1: Commenters 0530 and 0543 stated that the EPA has significantly underestimated the cost, reliability, and effectiveness of available air pollution control devices and the number of brick manufacturers that will be impacted by the proposed numerical limits. Commenter 0543 stated that this rule, as proposed, has the potential to significantly and detrimentally impact the brick industry, while providing no commensurate improvement to h uman health or the environment; C ommenters 0514 and 0560 agreed with this comment.

Commenter 0543 stated that the EPA made numerous unsupported

, unsupportable , and unrealistic assumptions in the proposal and supporting documentation, including assumptions that virtually all sources that remain in the category can comply with the standard. 22 Without considering the complex factors that go into such a decision, the EPA assumed tha t numerous sources would become non

- major sources of HAP and avoid applicability of the rule. In fact, nearly all benefits reported for this proposed rule, including both HAP and non

- HAP emission reductions, result from the sources that the EPA assumed wil l install controls to avoid the rule. All but 4 of the 440 tons of the HAP emission reductions claimed in the proposal are for HF and HCl emission reductions, primarily from sources that the EPA assumes will become synthetic
area sources; H owever, the comm enter asserted that the EPA has already demonstrated through modeling that the HF and HCl emissions from these sources cause no adverse impact to the environment.

The commenter asserted that the EPA incorrectly reduced the reported burden estimate for the proposed MACT by more than 90 percent from the more accurate estimate provided during the Small Business SBREFA panel review, when the EPA estimated that the rule could cost $188 million per year. The commenter noted that the $188 million per year did not include the control of Hg , which adds significantly to overall costs. While the proposal of a health

- based standard negates the requirement for new APCD to control HF and HCl in most instances, the commenter stated that the regulation of small amounts of H g and non

- Hg HAP metals has the potential to require the same multi

- million dollar controls plus the additional of an undemonstrated activated carbon system to reduce Hg emissions. Multiple commenters (0516, 0520

- 0523, 0529, 0536, 0537, 0545, 0550

- 0553, 05 55, 0556, 0558, and 0562) supported this comment.

C ommenter 0543 noted that by the EPA ’ s own estimates, these controls (and controls used to avoid MACT applicability) would reduce 118 pounds of Hg and 3.79 tons of PM HAP, but would cost $19 million each ye ar. The commenter asserted that the costs could actually be significantly higher, with substantially more sources being impacted. The commenter stated that the minimal, if any, emission reductions would not be commensurate with these additional costs.

22 See “Methodology and Assumptions Used to Estimate the Model Costs and Impacts of BSCP Air Pollution Control Devices” (EPA

- HQ

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- 0291

- 0118) and “Development of Cost and Emission Reduction Impacts for the BSCP NESHAP” (EPA

- HQ

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- 2013

- 0291

- 0117).89 Com menter 0543 was concerned about the model cost memorandum since it contains numerous assumptions that are either not supported by anything and are just “ assumed ” or are supported by a single telecon from a vendor who is clearly motivated to state that his equipment can meet any requirement. However, the commenter stated that the EPA appears to have been selective in which pieces of information it accepts from a vendor and which it does not, ignoring costs or other information provided. The commenter provide d the following examples:

• In the previous cost analyses for the 2003 MACT, the EPA used a lifetime for APCD s of 10 years . However, in the analysis to support this rule, the EPA changed the lifetime used in the analysis to 20 years, without justification of documentation. Other costs were simply escalated to 2011 dollars.

• The costs are reported in 2011 dollars with no explanation. A rule proposed in 2014, promulgated in 2015 and largely implemented in 2018 and 2019 should have been estimated in more recent d ollar years.

• In one of the telecons documenting a discussion with a vendor (EPA

- HQ

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- 0221), in which the vendor says that ACI systems would work for brick operations. The telecon then discusses the vendor statement, stating, “ He said that they sell silos of carbon for $500K to $600K. ” Instead of following up to get the details of this cost, the EPA dismisses this cost because it was reportedly two to three times higher and “ may have been referring to processes with much higher flow rates than br ick kilns. ” Instead, the EPA took a lower number from a 2005 rulemaking and then still reduced that cost by scaling down to the flow rate of an average brick kiln.

• The justification for this less costly approach appears to be due to a second vendor who cla imed that you could just use a bag of activated carbon and a blower. The commenter stated that this is not a practical way to operate a system required for compliance. The commenter asserted that facilities would install a storage silo with a reliable, acc urate injection system with a variable injection rate so carbon isn ’ t wasted, and they could document the carbon flow rate, as required by the proposed MACT. No one would dump a bag of carbon in a bin with a blower, especially when they could have to inject 250 lb/day. In addition, the commenter stated that some of the ven dors that the brick industry has spoken to have indicated a concern that the addition of carbon could create an explosion danger that would need to be mitigated. The algorithm in the Hazardous Waste Combustor document is $90,000 capital cost scaled by (flo w rate in actual cubic feet per minute ( acfm ) /150,000)^0.7, making the cost for the much smaller flows in a typical brick plant about $30,000 for a 30,000 acfm kiln, before escalation to 2011 dollars. The commenter stated that it is not appropriate to scal e something as simple as the system they have casted by size

- it would likely be the same size system, you would just get deliveries of carbon more frequently for bigger kilns. The commenter noted that this algorithm also results in some ridiculous indire ct costs for the model kilns (startup $538

- $772, performance test $538

- $772, model study $1,076

- $1,544).

• The total capital investment is only $102,224 for the small model kiln , which is unrealistic and not based on current day facts. The commenter asserted that the EPA must, at a minimum, use costs that were provided for this industry and for a system that the vendor “ believed ” would work. The commenter noted that sound science would dictate that both the applicability to the industry and the costs should b e based on more90 than a vendor claims. The commenter noted that mixing costs for one system and claims for a more expensive system is bad science and should be corrected in the final rule.

• The EPA appears to use vendor claims that bag degradation will “ usua lly ” not occur if

“ the bags are continuously operated above the acid gas dew points .” ( p . 6 of Model Cost memo) The commenter stated that the EPA apparently uses this to justify costing out a fabric filter rather than a dry injection fabric filter for some applications, however, the EPA then goes on to use less than continuous operation for both small and large kilns by using only 7300 and 7800 hour s per year for small and large kilns, respectively. The commenter pointed out that there is no way that a kiln operated only those hours would remain above the acid gas dewpoints; therefore, the EPA either needs to use 8760 hours per year or cost out a DIFF. The commenter stated that there are some documents in the docket where the EPA is apparently trying to figu re out if they can just use a fabric filter to control PM/Hg on a brick kiln and refute industry concerns about the acid gas destroying the bags and a concern about bags degrading at high temperature. EPA

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- 0217 is correspondence from Gore t hat says “ HF destroys fiberglass, so PTFE bags would be needed if HF emissions are a concern. He noted that PTFE bags, unlike fiberglass bags, are chemically inert, but are very expensive, about 2 to 5 times more expensive than fiberglass. ” The commenter m entioned that there is no difference in bag cost between their DIFF model and their standalone FF model. The cost used in the analysis is based on the average from Section 114 survey response per cost memo EPA

HQ

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- 0118 Table B

- 2. The commenter noted that these would not be the polytetrafluoroethylene ( PTFE ) bags. The commenter also asserted that the EPA ignores the particulate reduction benefit that stems from the reagent filter cake buildup on the bags.

• While it is possible that a straight ave rage of values reported in a 2008 survey would give you average operating hours of 7300 and 7800 for small and large kilns, respectively, these are not reasonable hours to use for estimating the costs of a system. The average hours likely resulted from ave raging full operating kilns with kilns that were seasonal or only operated a fraction of the year, due to the downturned economy. In addition, as the commenter mentioned above, the EPA assumes that the temperature in the systems never drops below the dewpo int for the compounds when they determined that a DIFF was not needed and they based the rule costs on a DLA. The commenter stated that, as the EPA is aware, kilns are designed to remain operating constantly for months or even years once they begin operati on. To realistically estimate the impacts of a control, the EPA should use the more accurate estimate of 8760 hours. If not, the commenter suggested that the EPA must cost a DIFF for all applications and not a FF, as the HF and HCl, even in the small amoun ts emitted by a brick kiln would impact the APCD physical integrity and greatly reduce the lifetime of the unit.

• The EPA should also use the lower level of operating hours, perhaps as low as 50 percent of a full year, to better understand the impacts of th ese controls on companies with kilns that operate only part of the year due to low demand. These kilns are often located at their smallest businesses that will be most severely impacted by this rule.

Commenter 0543 stated that they conducted a brief survey of the industry to confirm or refute other key cost elements used in the cost analysis, the results of which were presented in a separate comment letter by C ommenter 0542. In the comment letter, C ommenter 0542 provided91 a summary table ( presented below) wi th several key factors that the commenter asserted the EPA had underestimated based on their findings, which provided the high, low, and average value obtained in their survey, as well as the number of respondents.

EPA Number of respondents High Low Average Hours of operation

-- small kiln (hours per year) 7300 7 8760 8760 8760

Hours of operation

-- large kiln (hours per year) 7600 7 8760 6840 8405 a

Electricity cost ($/kWh) b 0.07 19 0.143 0.055 0.083 Waste disposal cost ($/ton) 40 12 100 10 51.9 Limestone ($/ton) 40 12 120 10 58.17 Compressed air cost ($/1000 ft 3 ) c 0.024 3 0.4 0.3 0.363

a The commenter stated that the use of an average for this value is misleading, as 5 of the 7 respondents reported operating ho urs of 8760 and only 2 reported something other than 8760.

b kWh = kilowatt

- hour

c ft 3 = cubic feet

Commenter 0523 stated that the EPA underestimated the time and cost it will take for their company to implement this rule. The commenters requested that the EPA accept the information from their operations, along with other facilities within the industry, and develop more accurate esti mates for implementing this regulation. The commenters believed that the actual costs are unreasonable and unjustified giving the questionable ability for the untested controls to actually result in emission reductions. The commenter listed some examples o f the EPA ’ s underestimations:

• The EPA assumed that it takes about 2 hours per shift to operate a control device, with one hour of maintenance labor and 9 minutes of supervisory involvement.

• The EPA assumed that control devices will last for 20 years and th at the bags on lime

based systems will last for 5 years before they need replacement.

• The EPA assumed no turnover or need for retraining for APCD operators.

• The EPA assumed that they would have staff with enough technical expertise and available time to im plement this regulation.

• The EPA estimates did not account for the higher costs associated with the use of outside consultants, which would need to be utilized by small companies such as theirs.

Response 1: The EPA disagrees with the c ommenters ’ argument that EPA incorrectly reduced the burden estimate for the proposed MACT by more than 90 percent from the estimate provided during the SBREFA panel review . The commenters ’ argument is based on a fa ulty comparison. T he commenter s mistakenly compared the $188 million capital cost provided during the SBREFA panel review with the $18.4 million annual cost stated at proposal. The capital cost stated at proposal was $54.9 million . The difference in the $188 million and $54.9 million capital costs is due t o several factors. The $188 million cost estimate was for straight MACT floors for both acid gases and PM

, did not include compliance flexibilities such as the health

- based92 standard for acid gases, and did not account for the expectation at proposal that f acilities would install less expensive DLAs to become synthetic area sources rather than install more expensive DIFFs to meet the MACT limits.

The EPA disagrees with C ommenter 0543 ’ s objection to the assumptions used in the proposal cost estimates

. T he cos t memoranda document the assumptions that had to be made where EPA did not have data. The commenter referred to these assumptions as “ unsupported ” but did not provide anything better that EPA could use instead.

The EPA also disagrees with Commenter 0543 th at EPA ’ s change of APCD lifetime from 10 to 20 years was unjustified and undocumented. In fact, the reverse is true. We reviewed the documentation cited for the APCD costs for the 2003 MACT and could find no basis for the 10

- year equipment life that was used at t hat time. The OAQPS Control Cost Manual suggests an equipment life of 5 to 40 years for baghouses, with 20 years being typical. Consequently, a typical 20

- year equipment life was used in the proposal costs. Regarding the comment about documentation, the mo del cost memorandum clearly states that DIFF costs were estimated following guidelines in the OAQPS Control Cost Manual, which includes equipment life.

Regarding C ommenter 0543 ’ s comment concerning the 2011 base year for proposal costs , t he proposal costs were provided in 2011 dollars because, at the time that costs were first being developed for the proposed rule, 2011 was the latest year for which an annual cost index value was available for scaling costs.

The EPA agrees with the changes to the operating hours suggested by Commenter 0543, and we have revised the costs to use the 8,760 hours per year suggested by the commenter from the results of their 2015 survey of the brick industry. We have also revised the costs to incorporate the suggested unit costs for electricity, waste disposal, limestone, and compressed air from the
commenter ’ s 2015 survey results.

Regarding C ommenter 0543 ’ s objection s to the proposal ACI costs

, the ACI costs were developed based on the best information available from vendors and were extrapolated to apply to the BSCP model sizes using standard extrapolation methods

. While the commenter provided specific objections to the ACI costs in their public comments, t he commenter did not provide any changes specific to the ACI costs that can be incorporated into the costs for the final rule

. However, w e have incorporated the commenter ’ s suggested changes regarding operating hours, electricity cost, and waste disposal cost into the final ACI costs

. Commenter 0523 argued that EPA under estimated the cost to implement the rule and provided some examples of what they considered EPA ’ s underestimations. The commenter requested that EPA accept the information from their operations . However

, the commenter did not provide any specific changes i n their public comment s

.

Comment 2: Multiple commenters ( 0514, 0516, 0518, 0520

- 0523, 0529, 0536, 0537, 0545, 0550

- 0553, 0555, 0556, 0557, 0558 , 0559, and 0562) stated that the proposed rule represents unreasonable and unwarranted levels of control for PM

, Hg and non

- Hg metal HAPs that are too expensive for the industry

. The commenters argued that installing and operating controls for PM

,93 Hg and non

- Hg metal HAPs could cripple their facilities and the industry as a whole, while providing little to no protection to the environment.

Commenters 0514

, 0522 , 0527 , 0557, and 0558 argued the controls necessary for PM

, Hg

, and

non

- Hg HAPs are not cost effective. Commente r s 0514 and 0522 noted that the costs for installing and operating DIFF on a small uncontrolled kiln will require capital costs of $1,368,356 million and annual operating costs of $437,121

. This would result in an average emission reduction of 170 pounds o f PM HAP and less than 3 pounds of Hg . The cost effectiveness of the Hg and PM is $7,422,000 per ton, while the effectiveness of Hg alone just under $ 471,268,000 per ton. The commenter s noted that these costs are based on using DIFF, because the commenter s believed that a FF will not work.

Commenter 0557 noted the HAP reductions for Hg and non

- Hg metal HAP total less than 4 tpy and that the average cost would be $4,750,000 per ton of HAP reduced. The commenter noted that the remaining 336 tons of HAP reduc tion claimed as a benefit of this rule is HF and HCl, which the EPA demonstrated do not impact human health and the environment in the quantities emitted. This commenter suggested the EPA reassess whether the rule is justifiable given the costs of this rul e compared to the benefits.

Commenter 0527 stated the EPA ’ s estimate of the cost to install and operate FF ( $1.22 million with an annual operating cost of $544,000 ) is too expensive for the ir company.

Commenter 0558 stated that their company has multiple kilns that do not have control devices but may be required to purchase and install control devices to comply with the Hg and non

- Hg metal/PM limits. Even if their kilns meet the acid gas emission limit without controls, the
commenter noted th at the limits for Hg and non

- Hg metal/PM emissions would still require them to purchase and install control devices. This would mean that millions of dollars will be spent to control emissions that represent less than 1 percent of the HAPs originally conside red for regulation in this rule. The commenter recommended the EPA consider the costs for situations where a plant must install a DIFF with lime and activated carbon injection to meet the Hg and

non

- Hg metal/PM limits. Commenter 0518 stated that the abilit y of clay brick manufacturers to meet the proposed Hg and non

- Hg metals has been over simplified and is a costly item.

Some c ommenter s (0518 and 0537 ) thought the EPA ’ s cost estimates were oversimplified and

unre a listic, and asserted that EPA had underest imate d the true costs of installing and operating controls. Commenter 0537 noted the EPA based costs on operating hours of 7300 and 7800 hours per year for small and large kilns, respectively. Th is commenter stated that kilns are designed to operate contin ually and the average used by the EPA appears to be based on a kiln that only operated for a fraction of the year.

Commenter 0559 expressed concern that the costs of control devices will make their product less desirable and that they would need to make ch anges to all the product styles.

Commenter s 0514, 0522, 0559, and 0563 stated that the controls are unproven and some of the controls may not work

. These commenters stated that if there is no assurance the controls will work, there can be no assurance that the limits will be met, and a huge amount of money could94 be spent for nothing.

. Commenter 0563 asserted that fabric filters with carbon injection has never been used in their industry

, there fore, there is no assurance that it would technically work. Commenter 0537 stated that the controls are not demonstrated since no one has installed a fabric filter after a DLA in the brick industry. This commenter also noted that no one has ever installed a standalone fabric filter without the dry injection system. Commenter 0527 noted that the FF for PM control has never been used at a brick plant and may not be feasible.

Commenter 0537 stated that the control devices they currently have installed (all DIFFs and 1 DLA) demonstrate very limited if any Hg reduction. They further noted that in one case of concurrent inlet and outlet testing, the Hg emissions were slightly higher at the control outlet. As a result, the commenter questioned the EPA ’s modeling results and asked what the cost of controls would be if they can ’ t make the limit using the modeled add on controls.

Response 2: Regarding commenters ’ objections to the high cost effectiveness of meeting the limits for PM

, Hg and non

- Hg metal HAPs

, while cost cannot be considered a factor for MACT floor standards, E PA has revised the Hg emission limits for the final rule based on information received from the industry, which is estimated to reduce the number of sources subject to the limits and thereby reduce the compliance costs. Regarding commenters ’ claims that th e emission controls needed to meet the limits may not be feasible, t he commenters have not provided

s pecific data to demonstrate the infeasibility of the emission controls, which have been demonstrated for similar sources

, e.g., Portland cement kilns

. Comm ent 3: Commenter 0539 commented on the cost of Hg sampling for compliance with the Brick MACT. The commenter mentioned the EPA suggested the testing be done by EPA Method 29. The commenter noted that the sampling costs for 3 runs and blanks coupled with th e pre

- test cleaning and calibrations are $6

, 900 including a normal report, and the analytical costs for the samples and blanks are $2

, 000. The commenter stated that these costs include the method stated blanks and the field/proof blanks that should be incl uded. The commenter stated the new requirements are Audits ($1

, 000), ERT ($2

, 000) and Compliance and Emissions Data Reporting Interface ( CEDRI ) ($2

, 000) , which mak es the total cost about $15,000.00 per test . The commenter stated that method 29 is one of the more expensive test methods. The commenter stated that this cost does not include the other metals that might be required, and suggested that the EPA needs to adjust all of their cost estimates to include realistic costs.
Response 3: T he EPA agr ees with the commenter ’ s request and has revised the t esting costs for the final rule to incorporate the additional cost items mentioned above.

Comment 4: Commenter 0543 stated that the EPA assumed numerous facilities are already or will become synthetic minor/area sources if they have existing APCD on all tunnel kilns within the facility . According to the commenter, the EPA state d that the sources would already be synthetic area/minor sources and not subject to the MACT because the change could be made “ a t little to no cost ” and then account ed for no costs from these sources. The commenter asserted that this is not valid because such facilit ies would need to conduct stack test s to verify emissions, develop a permit application, and develop and implement a program to implement the permit requirements. The commenter suggested that these costs would not be incurred in the absence of the rule and must be considered as costs imposed by this rule. Th is commenter mentioned that the EPA ’ s approach also ignores the following additional concerns that must be addressed :95 • According to the EPA, if the tunnel kilns are co

- located with periodic kilns, the periodic kiln emissions must be included in the determination of major source status. There is no evidence in this memor andum that the EPA included emissions from co

- located periodic kilns in their analysis.

• According to the EPA, the remainder of the EPA ’ s assessment basically concludes that virtually all small kilns can meet the proposed rule. If the EPA makes this assumption, it is unclear why a facility would unnecessarily take a limit that could potentially impact future growth.

• According to the EPA, a synthetic minor/area permit can also have an impact on future growth and can also add to a facility ’ s reporting b urden as some states have different requirements for sources that are attempting to remain below regulatory limits. The EPA cannot simply assume that a facility that has thus far elected to remain a major source has not considered the options and chosen to remain a major source.

Commenter 0543 suggested that any potential cost savings would need to be considered and weighed against the impacts of becoming synthetic minor/area. The commenter noted that it appears that the EPA ’ s assumption reduced the annual cost of the rule by less than $2 million per year, less than other assumptions discussed in this section, however, the assumptions seemed to be used to provide the EPA with virtually all of the benefits claimed by this rule. The commenter noted that, in to tal, the 14 sources assumed to install DLAs to avoid the rule provide 87.7 percent of the annual HAP emission reduction claimed by this rule (386 tons of the 440 tons), 23 as well as 99.6 percent (254 of the 255 tons) of the annual S O 2 reduction. The comment er suggested the EPA reassess the potential for sources becoming synthetic area/minor sources, and greatly reduce the number of kilns assumed to do this. While it is a viable approach that the industry will consider, the commenter asserted that the EPA ’ s a nalysis does not address the real evaluations that must be considered. While 14 sources is not a large percent of the industry, it represents 25 percent of the sources that the EPA had determined would otherwise be subject to the Brick MACT. The commenter also questioned whether the ability for the sources to borrow the money
to “ avoid ” the rule was included in the Regulatory Impacts Analysis.

Multiple c ommenters ( 0516, 0518, 0521, 0522, 0523, 0528, 0536, 0543, 0545, 0550, 0555 0556, and 0557 ) argued that E PA has oversimplified or does not understand the complexity of the decision to become a synthetic minor/area source. While companies will evaluate whether installing a DLA to becom e a synthetic minor source is a possible and less expensive option

, other fa ctors must be addressed. Commenters gave the following reasons for this assertion:

• A facility could not make the determination of non

- major status exempt from the MACT requirements without completing stack tests.

• Becoming a minor source can be an expensive proposition. At the June 2013 SBREFA meeting, the costs to “ opt

- out ” were estimated as $2.6 million with annual operating expenses of $800,000. C ommenter 0522 suggested the EPA refer to the attached comments submitted after the June SBREFA meeting.

23 An additional 46.8 tons of the HAP emission reduction (10.6 percent) is shown by EPA as coming from gaseous HAP emission reductions from one facility needlessly removing an ESP/SD and replacing it with a DIFF to meet the HCl equivalent standard. This facility models as well below the level established by EPA as safe, but w ould be required to install a control nonetheless to meet the HCl equivalent limit.96 • One co mmenter observed that the kiln exhaust stack temperature for one of their kilns never/rarely reaches 300 degrees F, the temperature at which the EPA states facilities must stop venting to the control device to avoid damaging the system.

• State agencies can impose additional permit limits, special requirements, and restrictions on facilities that become synthetic minor/area sources. The commenters asserted that these restrictions and special requirements would limit their ability to respond to market changes and grow if demand for their product increases.

• The majority of the small kilns in the EPA ’ s analysis have never been stack tested. Even though the EPA used slightly more conservative assumptions for facilities with no test data, there is no assurance tha t a facility would be able to comply with the synthetic area/minor emission levels without a stack test and any regulatory authority would require such a test.

• There may be additional state limits and restrictions that, should they become a synthetic minor, may limit their ability to respond to market changes.

• Switching back to a major source would be burdensome and costly, if a company becomes a minor source and then needs to expand.

• Some companies currently have facilities with a DLA (installed as a result of the first NESHAP) that will not meet the synthetic minor source definition and will require additional controls.

• Commenter (0528) stated that, while their company is operating a dry limestone absorber, DLA, on one kiln, they also have two small uncontrolled kilns that would also need to be controlled to consider this option.

• Companies would need to evaluate whether they could comply with the MACT limits before they e xpend any effort to determine whether they could become a synthetic minor

source.

• C ommenter 0528 stated that they have heard of cases where a state will include additional restrictions on plants that request synthetic minor source status and that these restrictions limits the facilities ability to fully operate and grow. The com menter asserted that such operating limits would affect a company ’ s ability to survive long term because they must be able to grow their business.

Multiple commenters (0516, 0521, 0522, 0523, 0536, 0537, 0543, 0548, and 0550) stated that DLAs are not effe ctive if S O 2 and HCl concentrations are too high. Another commenter stated that DLA would be impractical for plants that use clay that is very high in sulfur due the high sulfur dioxide concentration. Before considering installing a DLA, the commenters sta ted that they would need to evaluate their overall stack emissions and determine whether a DLA is a viable option. The commenters noted that, according to one vendor experienced with the brick industry, SO 2 emissions above 18 ppm would make DLAs impractica ble [see docket for 2003 Brick MACT, Docket A

- 99

- 30, Item IV

- H

- 5], which means that the more expensive DIFF option would be required for many sources , resulting in additional capital expenditure. Therefore, before making multimillion dollar decisions, the commenters asserted that companies would have to evaluate far more information than the EPA considered in their analysis.

Commenter s asserted that they would need to consider all of these factors when deciding how best to approach compliance with the propo sed Brick MACT.97 Commenter 0557 stated that install ing a DLA to become a synthetic minor source was a reasonable approach, but questioned why they should be asked to install a DLA to control other pollutants (HF and HCl) that do not have a significant impac t on human health or the environment , when the DLA would not control Hg and non

- Hg hazardous air pollutants. This
commenter noted that installing the DLA would be a multi

- million dollar cost that may put the facility out of business.

Five commenters (0521, 0523, 0536, 0537, and 0550) suggested the only reasonable approach for evaluating the impacts of the rule, was to assume all impacted plants would be required to install a DIFF with ACI unless comprehensive test data for that plant is available to demonst rate otherwise.

Response 4: The EPA agree s with the commenters that the cost to become a synthetic area source should include the cost to conduct a stack test to verify emissions. Consequently, we have revised the cost to include the cost of Methods 26A and 29 testing for tunnel kilns. Because testing for periodic kilns is considered technically and economically infeasible, facilities would be expected to estimate their p otential

- to

- emit through other means (e.g., emission factors), so no testing cost would be applied to periodic kilns.

The cost to apply for a permit modification would vary from facility to facility, depending on their location and how close they are to pe rmit renewal. If the facility is in the last 2 years of its permit, then the permit would simply be revised during the next permit renewal, with no additional cost expected. If the facility is in the first 3 years of its permit, then the permit would need to be revised prior to the compliance date 3 years after promulgation , with no additional cost expected above what would be incurred if the facility decided to comply with the rule

. Any impact of this option on the potential future growth of a facility wo uld be hypothetical and cannot be estimated. Similarly, the impact of any additional compliance requirements that a state might potentially inflict also cannot be estimated.

Regarding the comment about the viability of DLA installation if sulfur oxides ( SO x ) stack emissions are >18

- 20 ppm , the amount of sulfur in the raw materials would be very site

- specific, even within a particular site, and the commenters have not provided any specific information to the EPA in their public comments to enable the EPA to include such information in its analysis

. With the addition of Method 26A/29 testing costs, we have reevaluated the potential for sources to become synthetic area sources and revised the cost analysis accordingly. The results are documented in the nationw ide impacts memorandum for the final rule.

The Regulatory Impact Analysis has also been revised for the final rule to consider the ability of sources to borrow the funds necessary to install controls to become synthetic area sources. The results are docume nted in the final RIA.

Comment 5: Commenter 0543 stated while the use of sources with data as a predictor of compliance percentage for units with no data has a history in MACT development, it must be used with caution. It is important to consider the popul ation of sources that are being evaluated98 to ensure that the types of sources are reasonably similar and that the data has a reasonable potential to predict the likely outcome of remaining sources. The commenter stated for example, when evaluating the abil ity to comply with the PM limits, the EPA grouped kilns by control status and evaluated percent of sources with data meeting the proposed limit within these distinct categories; it is impossible with the data provided in this memorandum to calculate the pe rcent of kilns within the category with stack data since the EPA changes between the number of sources in the category and the number of sources in the industry interchangeable and generally without explanations. 24 However, the commenter recognizes that the re is a reasonable population of data for large kilns and concur that it is reasonable to assume that the PM data for DIFF and dry lime scrubber and fabric filter ( DLS/FF ) controlled units that meet the standard represent a reasonable estimate of the number of similarly controlled kilns without data that would be able to meet the limits; however, the EPA should assess whether these assumptions make sense each time they

use them and use more conservative approaches, as necessary, to ensure that they are not irresponsibly lowering their burden estimates.

Commenter 0543 stated the EPA should not base the ability for all 77 small, uncontrolled kilns to meet the Hg standard on a single stack test of a controlled kiln, even if that control is

“ believed ” to not control Hg . This is particularly egregious when a single test was the only test used to set the standard. The commenter stated it is clear that the stack test that was used t o set the emissions limit would meet the standard based on that single stack test; however, that same facility has identified that the brick being produced on the day of the test do not represent the material believed to be the highest Hg emitting; therefo re, this same kiln may not be able to demonstrate compliance with the current limits if the test were to be conducted with a different product.

Commenter 0543 stated using the fact that the stack test for the single tested small kiln could meet the limit t hat was calculated based on that stack test, the EPA assumed all small kilns could meet the standard, thus avoiding inclusion of any Hg controls on 77 small kilns; without th is assumption, the EPA would have had to include the cost, at a minimum, to instal l and operate a FF and ACI system. The commenter asserted a DIFF with ACI would be need to be costed out for this scenario, although the commenter continued to assert that there is no data to support the EPA ’ s assumption that these controls could reduce Hg to the proposed limits. The commenter stated the EPA does not even present the costs of a DIFF with ACI option on a small kiln in the memorandum; the EPA estimates that the FF alone would cost $1.2 million control, with an annual cost of $437,849. The com menter stated an ACI system for a large kiln is estimated by the EPA to cost $146,697 in capital costs with annual costs of $96,482. The commenter asserted that these costs are an underestimate for a large system, as well as a small system. The
commenter u sed the large kiln ACI cost as an estimate for a small kiln to calculate cost effectiveness; using the available the EPA costs, installation of a DIFF with ACI on a small kiln

24 Table provides the Nationwide Baseline Estimates for the source category; however, when assessing data, EPA considered the entire industry, including synthetic minor sour ces that are not part of the regulated category. Therefore, for example, Table 3 lists 14 DIFF or DLS/FF controlled kilns in total for the category, but Table 5 lists 28 DIFF or DLS/FF having data.99 would cost $534,331 annually to reduce approximately 0.00136 tons (2.7 pounds) f or a cost effectiveness of $393 million per ton, if ACI would even work for brick sources.

Commenter 0543 stated because there is no Hg testing for uncontrolled small kilns, there is no way to able to accurately predict at this time what percent of the facilities would be able to comply with this standard. The brick industry has begun a raw material testing program to begin to assess the potential compliance; 25 based on preliminary review of the data, the commenter asserted that some fraction of small kilns will be able to comply with the standard, but the Hg study is not complete. The commenter stated those that cannot meet the standard wi ll face these astronomical costs that the EPA ignores in their analysis.

Commenter 0543 asserted that it is wrong for the EPA to assume 100 percent of small kilns can achieve compliance with the Hg standard; the ability to comply or not comply will complet ely depend on the amount of Hg that was deposited in the mined material millennia ago. The commenter stated if a facility cannot meet the limit without control, they will either have to install the control listed above and hope that it works, attempt to be come a non

- major source if that is possible, or cease operations.

Commenter 0543 stated similar to small kilns, the EPA grouped uncontrolled and controlled large kilns into a single evaluation; this time the EPA has data from 18 DIFF

- controlled kilns and f

ound that 16.7 percent met the lb/ton limit and 55.6 percent met the concentration limit. The commenter stated the EPA then applied 55.6 percent to all categories of large kilns to arrive at the number of kilns that they believed could meet the standard; w ithout a determination that a DIFF achieves no Hg control, there is no justification for applying this percentage to any other group. In fact, absent data, the commenter stated the EPA should take the conservative approach of assuming that no kiln meets th e Hg limits; at most, the lower percentage of 16.7 might be used; however, there is no real basis for its application.

Commenter 0543 stated this highlights the brick industry ’ s concern that there is simply insufficient data available to justify a numeric limit for Hg at this time; absent more data, the EPA must assume a higher percentage of noncompliant sources and accept that the potential cost of this rule is far higher than they stated in the proposed rule.

Commenter 0543 listed some additional assumpti ons made in the “ Development of Cost and Emission Reduction Impacts for the BSCP NESHAP ” memorandum that apparently have data support; while the commenter understands that assumptions need to be made, the commenter requests that the EPA provide some justif ication and support in the final memorandum to support this rulemaking.

Commenter 0543 stated for large kilns with a DIFF or DLS/FF, it was assumed that the kiln stack not meeting either the PM lb/ton or concentration limits would meet the total non

- Hg HAP metals lb/hr limit.

• There is no reference to a memo or data that supports this assumption.

25 See BIA MACT TF letter submitted by Terry Schimmel and I rene Kuo for more information on this study.100 • The EPA based the lb/hr limit on an average percentage of the best performing sources in the floor pool; taking an average of the best performing sources further bi ases the data set. The commenter did not assert that this is the correct approach since it would automatically mean that anyone above this “ average ” metal content would be out of compliance with the rule. The commenter asserted that this overstates the num ber of sources that will comply with this limit format.

• The high potential for problems Test Method 29, used for metals measurements, such as permanganate contamination, could further challenge sources to demonstrate compliance with this alternate limit.

C ommenter 0543 stated for large kilns with a DLA, it was assumed that one of the kiln stacks not meeting the Hg lb/ton or concentration limits would meet the Hg lb/hr limit; it was also assumed that this kiln stack is one of the 12 stacks that can meet one of the PM limits, so no FF would be needed.

• No basis or reference to a memo or to data that supports that this one kiln can meet any one of these numbers; since the two emission rates were established from completely separate populations of sources, there is absolutely no data to support that both limits would be able to be met by the same source.

Commenter 0543 stated based on the results of the analysis described in Section III of this memorandum, a total of 12 large uncontrolled kiln stacks are located a t facilities that could become synthetic area sources with installation of a DLA on those stacks; for large uncontrolled kilns, it was assumed that owners or operators of three

- fourths of these kiln stacks, or nine total stacks, would elect to install a DL A. The commenter stated to be conservative, it was estimated that most of the remaining kiln stacks would not be able to meet any of the Hg limits.

• In other areas of this memo, the EPA assumes that all who could potentially meet the synth levels automatica lly do; while assuming that only 75 percent meet it may be slightly more conservative, there is again, no basis for even this high an assumption provided by the EPA.

Commenter 0543 stated it was expected that most small uncontrolled kilns would be able to meet the total non

- Hg HAP metals lb/hr limit and would not need to install DLA to become a synthetic area source; therefore, for small uncontrolled kilns, it was assumed that a little over 5 percent of the total kiln stacks, or five total stacks, were loca ted at facilities that would elect to become synthetic area sources by installing a DLA. The commenter stated it was also assumed that 21 of the 24 remaining kiln stacks not meeting the PM lb/ton or concentration limits (88 percent) would be able to meet t he total non

- Hg HAP metals lb/hr limit.

• There is no basis provided for any of these numbers; the decision to become a synthetic area source is complicated and not without limitations.

• The metals percentage used for this calculation was not based on the sub set of small kilns, further weakening any rationale for its use.

Response 5 : When the EPA does not have emissions data for all sources that are expected to be affected by a rulemaking, some assumptions and estimation procedures are necessary to estimate101 t he cost and emission reduction impacts of the rulemaking on those sources. The assumptions and estimation procedures are based on the best information available at the time. However, where data are not available and there is not a clear “best” estimation p rocedure , the EPA must use best engineering judgment to complete the analysis

. Some of the assumptions noted by the commenter are the result of engineering judgment based on experience with air emission controls from similar industries. The EPA does note that some assumptions and calculations were updated for the final rule analysis, including the incorporation of Hg content in raw material samples provided to the EPA by BIA. The methodology that the EPA used for the final BSCP Manufacturing NESHAP is docu mented in Development of Cost and Emission Reduction Impacts for the Final BSCP Manufacturing NESHAP in Docket ID No. EPA

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Comment 6: Commenter 0543 stated that there are several places within the cost and emission reduction impacts memor andum where numbers do not agree with previous tables. The commenter asserted that the EPA does not clearly state when the population they are counting includes only those major sources in the regulated source category and when they are referring to the en tire industry. The commenter disagreed that the EPA uses these terms interchangeably, especially when looking at the MACT floor for existing sources. However, the commenter noted that it is clear that the EPA understands that these are two distinct populat ions when determining the impacts of the proposed rule. The commenter suggested that EPA clarify the table headings or footnotes to indicate which group they are summarizing in each table.

In addition, Commenter 0543 noted the following apparent typos in t he memorandum:

• Table 3 indicates a total of 75 small kiln stacks (out of a total of 150) with one vented to a DIFF; Table 4 shows 79 small kiln stacks (out of a total of 132 stacks, reduced based on first “synth” cut) with 1 vented to a spray dryer with ES P ( SD/ESP ) ; Table 5 repeats the numbers contained in Table 4.

• Page 5 states that 15 of 86 would become synthetic sources; Page 8 says 14 sources would become synthetic area sources.

• Table 6, p 9, has a typo

- the large kiln, DIFF line indicates 4 kilns would install ACI , but the total in that column is only 3.

• Table 7 indicates that 3 small kilns would need to install a FF to comply with the rule (this is supported by the text that st ates that “21 of 24” would meet the hourly rate). However, the next two tables include only 2 small kilns.

Response 6: The EPA agrees with the commenter that the population counts should be clear in
t he memorandum documenting costs and emission reduction i mpacts. The memorandum for the final rule, Development of Cost and Emission Reduction Impacts for the Final BSCP Manufacturing NESHAP in Docket ID No. EPA

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26 Sroka, K. Development of Cost and Emission Reduction Impacts for the Final BSCP Manufacturing NESHAP

. Memorandum from Kristin Sroka, RTI International, to Sharon Nizich , EPA/OAQPS/SPPD. September 24, 2015.

27 Sroka, K. Development of Cost and Emission Reduction Impacts for the Final BSCP Manufacturing NESHAP

. Memorandum from Kristin Sroka, RTI International, to Sharon Nizich , EPA/OAQPS/SPPD. September 24, 2015.102 Specific apparent typos are addre ssed below:

• The difference between Table 3 and Table 4 is related to the difference between kiln size and APCD size . Two small kilns vented to one stack may have a large enough capacity to require a “large” size APCD. Table 3 is grouped by APCD size, and T able 4 is grouped by kiln size. For example, the SD/ESP controls multiple small kilns with a combined capacity large enough that the APCD is modeled as large. Therefore, it shows up as a large APCD in Table 3, but as controlling three small kilns in Table 4. We note that this difference was explained on page 11 of the memorandum, and we agree that the concept should be introduced earlier. Therefore, it has been moved in the final memorandum.

• The commenter is correct that the numbers of potential synthetic a rea sources and the kiln stack summations were not consistent at proposal; the errors have been fixed for the final version.

• Again, this is related to the difference between APCD size and kiln size. The total number of FF expected to be installed is four in both Table 7 and Table 8, and the bottom of page 11 explains that Belden Brick Company’s facility in Sugarcreek, Ohio, operates one of the small kilns that would not be able to meet the PM limit and would need a FF. This kiln is co

- vented with two other small kilns though, so for the purposes of this analysis, it was assumed that a large FF would be needed on one of the small kiln stacks.

15.2 Economic Impacts

Comment 1: Numerous commenters (0515, 0527, 0529, 0532, 0534, 0535, 0538, 0556, 0559, 0560, and 0562) expressed concern about the economic impacts the proposed rule could have

on their companies and the industry as a whole. Three c ommenters (0515, 0532, and 0538) argued the proposed rule is overly stringent and would force brick manufacturers to install unnecessary air pollution control devices

. The commenters argued that the high costs of control devices would do irreparable harm to the industry by causing some companies to take on large amounts of debt and many businesses to close

. C ommenter 055 9 stated that their plant will be unable to add even a small kiln because the proposed standard would impose an “ unbearable economic burden. ” Other commenters indicated their compan ies ha ve been impacted substantially as a result of the economic downtown a nd will be further impacted by the proposed rule. Commenter 0523 noted that obtaining financing for controls would hurt a company ’ s ability to obtain future financing for other projects, such as cost saving capital projects or expansion. This commenter als o noted that incurring the amount of debt necessary to finance control devices would impede a small company ’ s ability to weather future economic downturns. Many small companies in his industry, borrowed to finance expansions and other plant improvements be fore the last recession. More than a few of them went into bankruptcy, foreclosure, liquidation, or were forced to sell their plant to a large corporation because of that debt. C ommenter 0556 argued the industry has already suffered the consequences of a p oorly supported and constructed rule due to the previous MACT being vacated in 2007. They noted that their company installed 10 controls at its brick manufacturing facilities and spent considerable resources ensuring compliance with the MACT prior to the r ule being vacated.

C ommenter 0538 noted that the proposed rule would require kiln refurbishing that could cost up to two million dollars per kiln and cripple their industry. For their industry to make up two million dollars, the commenter noted that each kiln would have to produce at least 7 million103 extra bricks each, but doubted there would be demand due to continuing economic weakness in the construction sector

.

Commenter 0559 stated that the rule would prevent their company increas ing production because if they build a new small kiln or replace their existing kiln they would have to install costly control device s that may not even work. They argued that the proposed rule prevents them from becoming more efficient and more competitive.

C ommenter 0560 argu ed that companies would have to finance multi

- million dollar controls that have not been demonstrated to be effective in the brick industry. If the controls are installed and fail to perform as assumed, companies would have to close.

Many commenters (0518, 0522, 0523, 0529, 0530, 0531, 0548, and 0563) stated that their companies may be unable to obtain the financing for add

- on controls and may be forced to close

. Several c ommenter s ( 0522 , 0518 , 0523 , 0548

, and 0563 ) indicated the funding re quired to add controls may not be available to small businesses

. These commenters argued that such loans are not available for projects that do not increase production, enhance their product, or increase quality

. C ommenter 0518 stated that their recent exp erience indicate d it would be impossible for their company to borrow enough money for control devices. Another commenter stated that their company has been under strict borrowing limits since 2008 and have had to internally finance any equipment replacemen ts or upgrades. They noted that a lthough they were able to recently obtain $4 million for new equipment, this financing was possible because they were able to demonstrate that the purchase had a 3

- 4 year payback. Equipment financing without an economic ben efit that will pay back the loan is currently not available to their company through normal banking channels. Commenter 0548 stated that financing the controls would be out of range for small businesses and noted that their company recently had to seek pro tection under Chapter 11

.
Other commenters (0518 , 0531 , 0515, 0527, 0531, and 0532 ) stated that they may have to close the p lant if they are unable to obtain a loan. C ommenter 0531 also noted that the economy for the last 8 years has been extremely hard and stated that the financial burden placed on their company by adding Hg controls could mean the end of their company. The commenter was not sure that a bank would be willing to loan them 7 to 8 million dollars based on their financial situation over the last 8 years.

Two c ommenter s ( 0518 and 0531 ) were concern about the cost of compliance with the Hg and

non

- Hg metals standards

.

C ommenter 0529 argued that small kilns with production und er the 10 ton/year threshold should not be required to install and operate expensive control devices. This commenter noted t h eir
company spent millions of dollars to upgrading their existing plants but keeping their existing kiln in order to remain “ under 10 tons per hour ” to meet the definition of a small kiln . Without this limitation, they would have built an entirely different facility that would have been larger and more efficient. This com menter also noted that they have heard from a vendor that the co sts for controls on kilns operating at less than 10 tons will be about the same as controls for a kiln at 10 ton per hour. The commenter asserted it is definitely not cost

- effective to install control devices on small kilns such as theirs

-- existing or ne w.104 Two c ommenter s ( 0535 and 0559 ) asserted that the costs of installing and operating controls could not be passed onto their customers. The commenters stated that in today ’ s still recovering construction environment, passing on the costs of controls is n ot feasible.

Two commenters (0531 and 0532) asked the EPA to take a hard look at the costs and find a way to keep small family businesses viable, while still meeting the requirements of the CAA

. Response 1 : The EPA has been informed that firms may have difficulty obtaining longer

- term financing needed to buy the control equipment and make process changes needed to comply with the proposed standards. Firms may not have cash on hand or the ability to convert assets into cash in order to make these purchase s; as a result, firms would have to consider other long

- term financing options. Affected firms are less likely to be publicly traded and thus would be more likely to consider debt versus equity options. The additional liabilities can put firms at additiona l risk of closure if market conditions do not improve during the period when the rule is adopted. In addition, if creditors are concerned about existing or future market conditions in the brick industry, they may be less willing to enter a loan contract or may require higher rates of interest than the 7 percent interest rate used to annualize the capital costs associated with the rule. The EPA estimates of the range of the number of ultimate parent companies that may close rather than comply with the regula tion may be an underestimate because of the difficulty in obtaining financing at a 7 percent interest rate. The estimates might be an overestimate if the industry has become more robust by 2018 when the control must be in place. The closure estimate did no t include net effects on revenue due to price increases or reductions in sales attributable to the regulation.

Overall market impacts for the standard are estimated to be a less than 2 percent national average price increase and a less than 2 percent natio nal average reduction in production. Please see the RIA, Regulatory Impact Analysis: Final Brick and Structural Clay Products NESHAP found in the docket for more details.105 16.0 Statutory and Executive Order reviews

16.1 Executive Orders 12866 and 13563

C omment 1: Commenters 0530 and 0543 stated that the requirements of Executive Orders (EO) 13563/12866 were not met by this proposal because EO 13563 “ Improving Regulation and Regulatory Review, ” which supplements and reaffirms EO 12866 “ Regulatory Planning and Review, ” requires all federal agencies to adopt the least burdensome regulations that obtain regulatory objectives. EPA has failed to meet these requirements in this rulemaking since a significantly less burdensome option that achieves indistinguishabl e benefits exists, but was not proposed by EPA. While the EPA requested comment on a lower

- burden alternative that would require work practices rather than a numeric limit, the alternative was not the option selected by the EPA for the proposed rule langua ge. Compliance with the proposed numeric limit poses a significant economic burden for this industry and needlessly threatens the viability of numerous small businesses. However, EPA has not provided any information to support that the more burdensome nume ric limits creates any additional environmental benefit. Besides simply relieving costs, the commenter contended that a work practice standard is allowed under the requirements of the CAA section 112(h) because it is technically and economically infeasible to demonstrate compliance with a numeric limit. A work practice standard would fully meet the requirements for standards for these pollutants. Since this option is both acceptable under the CAA and represents less burden to the industry, the commenter bel ieves EO 13563 clearly directs the EPA to propose work practices for both Hg and non

- Hg metal HAP/PM.

According to the commenter, the EPA has yet to demonstrate that the controls they describe for costing purposes would even be viable for the process strea m characteristics (e.g., volumetric flow, PM loading, acid gas) found in a brick plant. Instead, the EPA justified the control of Hg from brick kilns using a transfer of technology demonstrated on larger process flows in other, larger industries and based on claims and assurances from control device vendors posturing to market their products. If the controls were as effective as EPA claims, EPA ’ s proposed approach would cost in excess of $300,000,000 per ton of Hg reduced. This per ton cost estimate is base d on EPA ’ s own analysis of the likely need to install and operate multi

- million dollar APCD to potentially reduce only a few pounds of Hg per year from a brick kiln. Since work practices under section 112(h) are justified in this case, selection of a more costly option based on undemonstrated technology is not justifiable.

Response 1: The EPA disagrees with commenters ’ contention that EPA was obligated to set work practice standards instead of emission limits for Hg

. During the 2010 testing program, Method 29 was used successfully to determine Hg and non

- Hg HAP metals in the emissions from BSCP plants. Method 29 was sensitive enough to have a majority of the test report above detection levels. Accordingly, because Hg and non

- Hg HAP metals are at measurable l evels, work practice standards for these pollutants are not applicable under CAA section 112(h)

.
The EPA also disagrees with commenters that there are no demonstrated emission controls available to the BSCP industry. Activated carbon injection and fabric filters have been demonstrated in a number of other industries as an effective control for Hg from their process units, including a similar process unit (kilns) used in the Portland Ceme nt industry. However, it106 is up to each facility to determine the type of emission control that works best for their particular situation.

Regarding commenters ’ argument about cost, it should be noted that under section 112 we cannot consider costs and oth er impacts when establishing MACT floor requirements. However, the EPA has taken significant steps to minimize the impacts of the rule on the small entities that are prevalent in the BSCP industry, while still achieving the objectives of the rule. In parti cular, the EPA has includ ed kiln size subcategories

, incorporated raw material variability factors into the Hg emission limits, and reevaluat ed stack test data used in developing the MACT floor PM surrogate emission limits

. 16.2 Paperwork Reduction Act

Com ment 1: Multiple commenters (0523, 0542, 0543, and 0563) asserted that the EPA has underestimated the burden and cost for the BSCP industry to comply with the proposed rule. The

c ommenter s variously gave the following reasons supporting their argument that the EPA significant ly underestimate d the burden estimate :

• The EPA underestimated the amount of time needed for each activity, the number of occurrences of each activity, and the level of staff needed to comply with the rule.

• E PA under estimate d time needed for “ reading and understanding ” the regulation

. The EPA estimated it will take a facility 2 hours to “ Read and understand rule requirements ” and argued this was insufficient time for an individual to read both the final preamble and regulation

, particularly if the final rulemaking is as long as the proposal. T he preamble and rule for the proposal the BSCP was 57,658 words and argued a single individual would have to read at a speed of 480 words per minute to read the preamble and rule in 2 hours

. T he BSCP rule is 18,088 words and would require the person to read and retain information at a speed of 150 words per minute. T he 2

- hour estimate is not reasonable and argued the average person can proofread at about 200 words per minute on paper and 180 words per minute on a monitor. 28 T he EPA incorrectly assumes only one person would read the regulation for a facility. A rule of this importance would be reviewed by managers and not by hourly, technical staff, as indicated in the EPA ’ s burden estimates. A manager would spend significantly more than the 6 minutes the EPA allocated to “ read and understand ” this rulemaking and would need to not only read the rule, but would need to develop calculations to determine how the rule would impact their operations a nd determine which sections of the rule required more understanding. For the brick industry, this level of expertise does not always exist at the plant or company level and consultants would need to be hired. T hese costs should be reflected in the burden a nalysis.

• The EPA underestimated the number of hours for annual employee retraining and training new employees. The EPA used data provided by stakeholders and the estimate of six plant personnel for 40 hours each is likely still reasonable; however, it is n ot reasonable to assume this is a one

- time training. Most facilities would need at least annual training, as well as training of new employees. A more reasonable approach would be to include a lesser level of training every year after the first year

. .

28 Ziefle, M (December 1988). “Effects of Display Resolution on Visual Performance.” Human Factors 40 (4): 554

- 68.107 • T he EPA incorrectly attributed costs to each facility , when those costs appl y to each kiln. C ompliance demonstration through initial performance tests, monitoring of parameters, and submittal of compliance tests must be conducted for each kiln. In some instanc es where kilns are co

- vented through a single APCD, counting each facility may seem reasonable; however, in most cases there is no co

- venting, and costs would be incurred for each individual tunnel and periodic kiln. It is not reasonable to assume all kiln s within a facility will be ready for compliance testing at the same time.

• The EPA omitted costs to research untested control strategies . These control devices would require significant research and probably pilot studies before a control device can be se lected

, costs quote s from vendors reviewed and the unit installed. M any facilities would likely require a preliminary stack test to determine their baseline and to ensure the controls will m eet numeric limits. T hese costs, whether incurred by the individual companies or the industry as a whole, cannot be ignored when assessing the financial impacts of th e regulation, because they are costs th e industry “ would not have been incurred in the absence of a rule ” and shoul d be included in the “ capital/startup ” costs begin ning in the first y ear.

• The EPA failed to correctly include hours for completing daily VE checks and preparing documentation of the checks

. I t would take a trained hourly technician three

- quarters of an hou r to an hour per kiln per day to conduct VE checks

, including arriving at appropriate spot, conducting the minimum 15 minute of observations, and returning to office and documenting results

. For 67 affected entities, this would be a minimum increase in the average burden per facility of 274 to 365 hours per entity. T he EPA should not include the burden estimate for the daily VE checks in the “ annual O & M
costs ” because this approach masks a significant annual burden and incorrectly excludes the total hours for daily VE checks from the total hours.

• T he EPA made unrealistic assumptions that were not based on input from industry. While the brick industry did provide some limited data to the EPA during the previous and now vacated rulemaking, the EPA made little attempt to gather new or additional data during the current rulemaking. The EPA omitted costs incurred by sources that the EPA anticipates will become synthetic area sources to avoid MACT applicability. If a facility opts to become a synthetic area source, it will continue to have reporting, recordkeeping and monitoring requirements. T hese burdens would not have been incurred in the absence of this rulemaking and therefore, they should be counted as a direct impact from this rulemaking. I t is reasonable to assume that these burdens would be similar to most, if not all, of the burdens associated with compliance. While it may be reasonable to exclude their count from some requirements (e.g., electronic filing of reports, burner checks), the costs for these facilities should be included for performance testing, some level of parametric monitoring, and maintenance procedures.

• T he EPA failed to provide the basis for the number of facilities estimated to become synthetic area sources. T he EPA ’ s burden estimates assumed 25 sources would become synthetic area sources to avoid MACT applicability. The proposal did not clearly indicate whether the 67 facilities impacted by the rule refers to individual kilns or total facilities

, and the numbers of sources/facilities in the memorandum that addresses the capital and108 annualized costs of the rule 29 do not match this count. The supporting sta tement should fully explain all assumptions.

• The EPA ’ s estimates are based on unsupportable assumptions about the number of kilns that will be able to meet the floor limits. The EPA assumed all 78 small kilns would be able to meet the Hg limits because th e one small kiln with stack data, which was used to set the standard, could meet the limit that was set based on their own performance test.

• The EPA incorrectly divided the total number of average hours by an average number of

“ responses. ” The EPA should h ave calculated an average burden per respondent or affected entity. By dividing by responses rather than respondents, the EPA is artificially lowering the burden estimates. Since a facility may have multiple “ responses ” in a single
year, the total response s should be in excess of the 67 facilities the EPA estimates are impacted by the rule , particularly for Years 4

- 6 (e.g., Table 1

- 4 in Appendix 1)

. T he number of reports submitted does not provide useful information as the EPA could arbitrarily lower the im pact per “ response ” simply by adding in another report per facility. Correcting this error decrease s the average cost per respondent for Years 1

- 3, but increases the costs per respondent for Years 4

- 6

. The EPA should use the average cost per respondent in all analyses. The EPA failed to account for the costs associated with preparing the documentation needed to request a routine maintenance exemption under 40 CFR 63.8420(d)(1). I t is reasonable to assume that managerial level staff would develop this request, with some support from technical/hourly workers.

• The EPA underestimated burden for preparing the notification of compliance status and the first compliance report . The EPA estimated these documents would take 16 hours of an hourly technical staff to complete. B oth reports would take longer, with the initial compliance report taking significantly longer and would be prepared by managerial staff, not hourly workers. The EPA underestimated the costs of developing an operating, maintenance, and monito ring plan. T he EPA used stakeholder data from 2003 to estimate costs for develop ing an operating, maintenance and monitoring plan. Even if the estimates are reasonable, the plan would be prepared by key senior staff from several departments and not by hour ly technical staff as included in the cost estimate

. Consultants are also generally used to help generate these documents. I t is incorrect to assume that no revisions are required to these documents after initial development. These documents are typically reviewed and revised as new issues are identified.

• The EPA has not clearly indicated how many tests EPA is assuming or the costs of the tests. For example, it is impossible to definitively determine whether EPA used 67 facilities and whether that number ac curately reflects the number of kilns that will require stack tests or if EPA erroneously assumed that all kilns at a single facility would be tested simultaneously for the price to test a single kiln.

• The EPA estimates do not account for the higher costs associated with the use of outside consultants

. T he EPA should include as an operation and maintenance ( O&M ) cost the cost of external consulting help that will be required for most sources, particularly the small businesses, to assess their company

- specif ic impacts from this rule, assess compliance options, and obtain necessary quotes and permits to install and operate air pollution control devices.

29 “Development of Cost and Emission Reduction Impacts for the BSCP NESHAP,” November 6, 2014. K. Sroka, RTI International to J. Telander, EPA/OAQPS/SPPD.109 One c ommenter ( 0542 ) provided the EPA with results of a survey of 14 companies they conducted to assess the validity of the EPA ’ s hours and other cost factors used in the cost estimations for monitoring and reporting. The results are summarized below:

• Time required for r eading the preamble and the regulation : Survey responses ranged from twelve (12) hours to forty (40) hours for technical persons, one (1) hour to sixteen (16) hours for management persons and a half hour to ten hours (10) for clerical persons. These numbers are consistently higher than what the EPA has assumed.

• Time required for preparing an OM &M plan : The average time spent on this is expected to be 214 hours. The EPA did not include annual updates to the plan , which s urvey responses indicate would require an average of 34 hours for updates. Member companies estimated that they will be spending far more time on the OM&M plan than the EPA assumed, including some use of consultants at hourly rates far exceeding EPA ’ s estimates for plant personnel.

• Additional work not accounted for in the estimated burden: Members of the brick industry that were su rveyed noted th e following additional work will be need to comply with the rule:

o Update System for recording all monitoring parameters

-- Brick Industry estimated an average of 20 hours per facility

. o Recalculating all values in test report based on EPA ’ s gui dance on how to report values that are at or below the detection level of the test : Brick Industry estimated an average of 21 hours per facility

. o Annual re

- training or training of new employees : Brick Industry estimated 104 hours per facility

.

• W hen it come s to annual maintenance and inspection, the EPA estimated that 20 hours of a technical person, one hour of management, and two hours of clerical would be sufficient to complete the work. Respondents to the BIA survey asserted that this number is not so far off for a single kiln; however, for companies who have multiple kilns, or multiple plants, this number becomes an underestimation of the actual time needed. The EPA assumed a facility needs 20 hours of a technical person to complete all the maintenance an d inspection regardless of facility size. In their industry, a facility could have a single tunnel kiln or can have multiple tunnel kilns (up to 8 is known to occur) and dozens of periodic kilns. Clearly, the more kilns or locations, the more time will be dedicated to this task. The EPA also has numbers for annual burner inspection and tune

up that seem more appropriate for one kiln.

Response 1: The EPA disagree s with c ommenter s that capital/startup costs must include costs associated with demonstrating th e use of control devices for the BSCP industry. The control devices in question, baghouses and activated carbon injection, have already been demonstrated on similar processes (kilns) in other industries (Portland Cement).

The EPA agree s with commenter s th at the 67 sources refers to plants, not kilns. The supporting statement for the proposal referred to “ 92...major sources of HAP, ” 25 of which “ are projected to become synthetic area sources, ” with “ the remaining 67...expected to be subject to the rule. ” Major and synthetic area sources are determined on the facility level, not the affected source110 (e.g., kiln) level. The EPA disagree s with commenter s that the number of kilns subject to a particular limit is relevant in the calculation of facility burden for the BSCP rule.

The EPA agree s with commenter s that performance test costs associated with demonstrating synthetic area status should be included i n the cost of the rule, and the performance test costs for the final rule have been revised to include those costs. However, the EPA disagree s that the costs of continuous compliance, such as parametric monitoring and maintenance procedures, and the
costs of recordkeeping and reporting should be included for these synthetic area sources. Once the facilities have demonstrated their synthetic area source status, they are no longer subject to the requirements of the major source rule, including any continuous compliance requirements or recordkeeping and reporting requirements.

The EPA agree s with commenter s that the facility burden estimates should account for the number of kilns at a facility, and we have increased the burden estimates for each facility where necessary, based on the average number of kilns per facility. The performance test costs already account for whether kilns are vented individually or co

- vented (see BSCP Impacts memo).

The EPA disagree s with commenters ’ objection to the calculation of the burden per response. This calculation is required for Office of Management and Budget ( OMB ) review.

In response to commenters ’ concerns about the burden of the rule being underestimated, w e have made a number of changes to the burden estimates for the fina l rule. We have increased the burden estimates for respondents to read and understand the rule requirements, calculating a total of 12 hours for this task, using the methodology suggested by commenter s , based on a conservative reading rate of 100 words per minute for the 72,054

- word draft preamble and final rule (BSCP portions only). This burden estimate is within the range of the estimates provided in BIA ’ s survey of the BSCP industry . We have also revised the burden calculation to include only technical a nd managerial labor for this task, split 50/50, in response to commenters ’ concern.

W e have also increased the burden estimates for requesting a routine maintenance exemption (i.e., alternative standard as revised in the final rule), preparing the notifica tion of compliance status and first compliance report, developing the OM&M plan, etc. , based on estimates from the BIA survey. The EPA agree s with C ommenter 0542 that annual updates to the OM&M plan should also be accounted for, and we have estimated the b urden for this task based on estimates from the BIA survey

. The EPA disagree s with c ommenters that we assumed only one person would be involved in conducting these and other tasks, since we also included manageria l and clerical staff in the burden estimates . In addition, the burden estimates do not specify the number of people involved in conducting these tasks , only the number of hours. The EPA disagree s with

c ommenter s that manageri al staff should account for the majority of the burden for these t asks, which also conflicts with the labor breakdown of the burden estimates provided in BIA ’ s own survey results. There is also a great deal of variability in the labor breakdown (technical, managerial, clerical) in the BIA survey results, between companie s and between burden items. Consequently, f or consistency , we have retained the current ratio of technical to managerial and clerical burden for these and all remaining burden estimates. The EPA disagree s with commenters that external consulting labor must be accounted for in the burden estimates . As one111 commenter noted, these impacts are “ company

- specific. ” T he extent of th is burden and the number of affected facilities are not clear, based on public comments

. In response to comments from c ommenters on th e burden estimate associated with training personnel , w e have increased the estimate of training burden from 40 to 48 hours based on estimates from the BIA survey, and we have also added burden estimates for annual training from the survey results, to allo w for initial training for new staff and refresh er training for existing staff

.

The EPA agree s with c ommenter s that additional clarification is needed for the basis for the VE and stack testing costs at the bottom of the burden tables. We have added a stat ement in the corresponding footnote to clarify that these estimates come from the nationwide BSCP cost estimates in the BSCP Impacts memo. We direct the commenter s to this memo for further information on how these nationwide costs were estimated. We disagr ee with commenter s ’ contention that the VE tests are not an O&M activity but a labor burden. The VE tests are used as a monitoring method for demonstrating continuous compliance, and are not a recordkeeping or reporting requirement.

The EPA disagree s with C ommenter 0542 that burden estimates need to be added for the following:

• Development of title V permit application

-- all major source BSCP facilities already have title V permits, which would already be updated every 5 years even in the absence of a BSCP rule.

• Evaluation of control devices

-- the control devices that facilities may need to install to meet the BSCP emission limits have already been demonstrated on similar processes (kilns) in other industries (Portland Cement)

.

• Selection of control device ven dor

-- this cost should already be included in the capital
cost of the control device.

• Recalculating test report values at or below the detection level

-- this task is unnecessary to demonstrate compliance.

• U pdating system for recording monitoring parameters

-- t he BSCP rule has been designed to allow facilities to use existing systems to gather the necessary information to demonstrate compliance , so no system updating should be necessary

.
Comment 2: Commenter 0543 stated that the EPA should not use Years 1

- 3 aft er promulgation as representative of the actual data collection burden of this rule. The formal analysis of the three

- year average burden for the Brick MACT should not start in the year the rule is promulgated, since the rule primarily impacts existing sou rces, where compliance is not required until after the end of Year 3. Therefore, while control device costs would be occurring, the majority of reporting and recordkeeping requirements would be more limited until Years 4

- 6.

According to the commenter, by f ocusing on Years 1 through 3, EPA essentially cuts the true ongoing annual burden to one

- third of the actual burden using this approach. To truly evaluate the impact of a rule that largely impacts existing sources, the commenter stated that EPA should be r equired to conduct their formal burden assessment for Years 4

- 6 and address Years 1

- 3 in an appendix.112 Response 2: The EPA disagrees with the commenter ’ s argument that the EPA should not have

use d Years 1

- 3 after promulgation in estimating the data collecti on burden of the rule. The EPA is required to follow the requirements of the PRA in conducting its evaluation of the burden associated with a particular rule. Under the PRA, the EPA is required to estimate the burden every 3 years, beginning with the effec tive date of the rule (i.e., Years 1

- 3). Consequently, the EPA is following accepted guidance in providing the burden estimates for Years 1

- 3. As the commenter noted, most of the burden for the BSCP rule falls in Years 4

- 6 and beyond. While the EPA was not required under the PRA to do so, to provide a better understanding of the burden of the rule, we provided estimates of the burden for Years 4

- 6 in an appendix to the supporting statement. The burden estimates for Years 4

- 6 will be formally updated by the EPA 3 years after the effective date.
16.3 Regulatory Flexibility Act

Comment 1: Commenter 0517 stated that the burden a new MACT would impose on small businesses in the industry exceeds the purpose and intent of the CAA . The commenter noted that MACT is a technology

- based standard, set without respect to costs and benefits, and also noted that subsequent changes to the NESHAP must take into account costs. While the CAA provides no guarantees that all sources should be able to continue operating under a MACT

- based standard, the commenter mentioned that this particular industry had already complied with a MACT, and the need to set a new, more stringent MACT is due to the court ’ s decision to vacate and remand the previous rule rather than simply remand. The commenter therefore suggested that EPA should exercise its discretion under the CAA to the maximum extent possible to minimize the impacts on these already

- struggling sm all businesses. The commenter supported EPA ’ s proposals to set work practice standards and health

- based emission standards in all instances allowed by statute.

Commenter 0517 expressed concern that some of EPA ’ s assumptions in the economic analysis (as dis cussed in the paragraphs below) lead to significant underestimates of the disruption this rule would have on small brick producers.

First, Commenter 0517 suggested that the annualization of EPA ’ s cost estimates at seven percent over 20 years is inappropria te when considering the small business impacts. The commenter noted that annualization of costs assumes the availability of financing at these same terms, seven percent over 20 years. The commenter has heard from small businesses and BIA that financing is generally unavailable to small firms in the industry, even to expand productive capacity, and definitely not at these terms. The commenter stated that if financing is unavailable, then the small business must finance the initial capital costs out of cash

- o n

- hand and profits. The commenter stated that, given the size of the businesses involved and the capital costs required, most small businesses would have difficulty complying without financing.

Second, Commenter 0517 was concerned that EPA has underestimat ed the impact of the rule by assuming a number of small business can avoid compliance with the MACT by reclassifying themselves as “ synthetic minor ” sources, i.e., sources that do not emit enough to be major sources. The commenter noted that EPA estimates that 15 of the 86 facilities affected by this rule would only need to submit paperwork to come into compliance, but was concerned that this oversimplifies the decision. The commenter pointed out that if a small entity is already emitting113 below the threshol d, it is unclear why they would not already have been classified as a “ synthetic minor ” when negotiating their CAA permits. Given the permitting requirements that accompany the “ major source ” designation, the commenter asserted that it is more likely that small entities have other reasons for remaining “ major source, ” such as the desire to maintain capacity in the hope that demand for bricks will recover to pre

- 2007 levels. The commenter noted that, if so, reclassification can have real costs to the future viability of the firm.

Third, Commenter 0517 stated that EPA makes assumptions about the cost of reducing Hg emissions that affect its estimated impact on small entities. The commenter noted that EPA has Hg emission data for less than 10 percent of kilns b ut assumes some mix of controls used in other industries will be effective in bringing all sources into compliance with the Hg standard. The commenter stated that EPA ’ s estimates may not accurately capture the range of costs that would be imposed on small entities. The commenter also mentioned that small entities may not have the ability to develop a compliance strategy or understand what control equipment may be necessary, and providers of control equipment may be unwilling to guarantee performance. The

co mmenter was concerned that EPA has not recognized the significant disruption this proposed rule would have on the industry, and suggested that the economic analysis should reflect the practical difficulties this industry will likely experience in planning for compliance.

Finally, Commenter 0517 stated that small brick producers are very concerned that EPA ’ s proposed NESHAP for their industry will put many of them out of business. The commenter suggested EPA use its discretion to minimize the significant eco nomic impact on small entities consistent with the stated objectives of applicable statutes. The commenter recommended further consultation with small businesses to gather the data necessary to justify greater flexibilities, including a delay in promulgati ng a Hg emission standard to better understand the sources and possible controls for Hg in this industry if necessary.

Response 1: Regarding the commenter ’ s concern about some of the EPA ’ s assumptions in the economic analysis, the EPA understands that firm s may have difficulty obtaining longer

- term financing needed to buy the control equipment and make process changes needed to comply with the rule. Further discussion of this issue is provided in our response to the public comments in section 15.2 of this d ocument and in the RIA, Regulatory Impact Analysis: Final Brick and Structural Clay Products NESHAP found in the docket for this rule.

With re spect to the commenter ’ s concern about the EPA ’ s assumptions regarding the number of small entities that may choos e to avoid compliance with the MACT by reclassifying themselves as synthetic area sources , we have reevaluated the potential for sources to become synthetic area sources and revised the cost analysis accordingly. In response to other public comments, we ha ve also revised the cost to become a synthetic area source to include the cost to conduct a stack test to verify emissions. These results are documented in the nationwide impacts memorandum for the final rule. Concerning the commenter ’ s assumption for why small entities choose to remain major sources, such speculation o n the potential future growth of a facility would be purely hypothetical and, therefore, was not accounted for in our cost analysi s

. Regarding the commenter ’ s suggestion that the EPA should exercise its discretion to minimize the impacts of the BSCP manufacturing NESHAP on small entities, it should be noted that in114 addition to the work practice standards and HBEL mentioned by the commenter, the EPA has taken other significant steps to minimize the impacts of the rule on small entities

, while still achieving the objectives of the rule. In particular, the EPA has includ ed kiln size subcategories

, incorporated raw material variability factors into the Hg emission limits, and reevaluat ed s tack test data used in developing the MACT floor PM surrogate emission limits

. The incorporation of raw material variability factors into the Hg emission limits and the inclusion of updated cost factors from industry into our cost analyses were designed to address the concern about the adequately estimating the impact on small entities of complying with the Hg standards.
With respect to the suggestion by the commenter that the EPA defer taking action on setting Hg emission limits until more information beco mes available, the EPA notes that it is obligated to take final action to set NESHAP for BSCP facilities located at major sources on or before September 24, 2015 pursuant to the consent decree in Sierra Club v. EPA , Case No. 08

- 00424 (D.D.C.).115 17.0 General Comments
17.1 General Opposition

Comment 1: Commenter 0561 asserted that the rule could have unwarranted and unreasonable negative impacts on brick manufacturing operations and encouraged EPA to minimize these impacts. The y acknowledged the governm ent has the responsibility to protect human health and the environment , but asserted the country ’ s manufacturing base should be supported and encouraged to prosper at the same time. The CAA provides the tools for EPA to balance both of these goals

, and the commenter encourage d the EPA ensure that the regulation of small amounts of emissions from trace minerals in the mined material s does not needlessly jeopardize the viability of th e American brick industry. The commenter urged EPA to do more to create a ru le that meets the requirements of the CAA and allows brick manufacturing to remain a viable American industry.
Response 1: As stated previously, the EPA understands that variations in the raw material can affect the long

- term performance of the best perfor mers when complyi ng with a particular standard. Thus, the EPA has incorporated the data received during the post comment period into the development of the final MACT Hg standard for this category ; see Final Maximum Achievable Control Technology (MACT) Flo or Analysis for Brick and Structural Clay Products Manufacturing for more information. 30

17.2 Incorporation by Reference

Comment 1: Multiple c ommenters ( 0513, 0514, 0515, 0516, 0520, 0521, 0522, 0523, 0529, 0532, 0534, 0535, 0536, 0537, 0545, 0548, 0549, 05 50, 0551, 0552, 0553, 0555, 0556, 0558, 0559, 0560, 0562, and 0563 ) stated they support ed the comment letter submitted on their industry ’ s behalf by the Brick Industry Association (BIA), as well as all supplemental letters mentioned in that letter (letter from Susan Miller, Brick Industry Association, submitted March 2015 to Docket ID No. EPA

- HQ

- OAR

- 2013

- 0291).
Response 1: The EPA acknowledges the commenters ’ incorporation by reference of BIA ’ s comment letter and all supplemental letters mentioned therein

.

30 Raymond, G., and K. Sroka. Final M aximum Achievable Control Technology (MACT) Floor Analysis for Brick and Structural Clay Products Manufacturing . Memorandum from Gabrielle Raymond and Kristin Sroka

, RTI International , to Sharon Nizich

, EPA/OAQPS/SPPD . September 24, 2015

.116 18.0 Other Comments

Comment 1: Commenter 0543 noted the following typo graphical errors and clarifications in regulatory language:

• In Table 5 of the regulation, in the first column, the “ 8. Existing, new or reconstructed periodic kilns ” is missing.

• The BIA MACT TF requests that EPA allow that stack tests conducted within 5 years of date of notification of compliance status be acceptable as long as the company can assert that the operations a during the test are still representative of current operations and that all required data were collected during the test.

• In some cases, two or more kilns are vented to a single control device. EPA acknowledges this in their analyses. However, the compliance demonstration requirements do not appear to address this sit uation. The BIA MACT TF requests that EPA clarify that co

- venting through a common control device is acceptable.

• The EPA provides compliance demonstration procedures for the HCl equivalent standard for uncontrolled kilns and for controlled kilns. The BIA M ACT TF requests that EPA specifically state that a combination of controlled and uncontrolled kilns can be used to meet this limit.

• EPA should provide specific instruction on the use of “ non

- detects ” when demonstrating compliance with the HCl equivalent st andard. Specifically, a “ zero ” emission rate should be used for non

- detects found during Method 26A testing. Any value other than zero used for a non

- detect for Cl 2 would be multiplied by 133 and could make it appear that a facility was violating the HCl e quivalent standard when they have non

- detectable Cl 2 emissions.

Response 1: Concerning the comments on the regulatory language , we have the following
responses :

• We have revised Table 5 to subpart JJJJJ include the missing language for existing, new

or reco nstructed periodic kilns.

• We have elected not to provide for the use of prior test results in lieu of initial performance testing that the commenter requested . Given the recurring testing required under this rule, the allowance for prior test results seems unnecessary as a general allowance. However, a source can discuss with their delegated authority whether this option is available and feasible for their plant. In addition, a source may seek a waiver of testing under 40 CFR 63.7(h) of the General Provisio ns.

• Item 1 in Table 4 to subpart JJJJJ already specifies that sampling sites be located at the outlet of the APCD . No further clarification is necessary.

• Section 63.8445(f)(2) refers to each tunnel kiln at the facility, which would include all controlled and uncontrolled kilns. No further clarification is necessary.

• Regarding the commenter ’ s question regarding how non

- detects discovered during Method 26A testing should be treated

, calculation of the analytical detection limit is described i n Section 13.3 o f Method 26 A

. The detection limit needs to be calculated on a

run

- by

- run basis

, and the non

- detects should be the detection limit of the run which will include the analytical detection limit of the laboratory and the gas sample volume measured by the dry g as meter

.117 Comment 2: Commenter 0544 noted one of the challenges with an indexless, searchable docket is that you also need to have a general idea of the title of the document in order to find it. The commenter stated that when you have limited resources an d limited time to find and read everything, using multiple search parameters for the documents delays forward progress. The commenter suggested that a docket index would help speed up the process.

In addition, Commenter 0544 noted that once you are actuall y able to find the documents you are looking for, any attachments they may have are not labeled, have no page numbers, and are not formatted to be readable without printing and cutting out each page and reassembling it into usable format. The commenter not ed that this frequently happened with large tables that were

“ printed to file ” without first being formatted for printing. The commenter stated that what it comes down to is that the attachments to documents in their current form are often essentially
wort hless, unless you know exactly what you are looking for. The commenter asserted that being able to quickly understand what you are seeing when looking at an attachment is critical with thousands of documents to go through. The commenter stated that it is i mpossible to reference these pages in a comment letter and impossible to follow where key decisions were made. The commenter also stated that when writing a comment on the rule, understanding the assumptions that were made is very important. The commenter was concerned that if a comment letter cannot properly reference an attachment, how would the EPA even be able to figure out what the commenter is trying to say, or even be able to look into the claims of the commenter?

In addition, Commenter 0544 noted th at there seemed to be issues with the docket being loaded to regulations.gov early in the comment period. The commenter asserted that every moment that you have a document is critical to understanding the rule and preparing your comments. The
commenter not ed that Brick MACT appeared in the federal register on December 18, 2014, but as of December 19, there were no documents uploaded to the docket. The commenter noted that there were still many documents that were not available and many that had a title had no PDFs or other documents to download by December 22. The commenter criticized that this was a loss of critical time before the holidays. The commenter also noted that it was not until we moved past Christmas that most of the documents were available, and even then, there were duplicate copies of some documents under different item numbers, requiring additional review to determine whether they are in fact identical, which they were. The commenter noted that it was not until sometime later when going back t o review these identical files for this comment letter that we noted that they were changed to different files. The commenter stated that it would have been beneficial to have these files initially as the main comment letter for the Brick Industry Associat ion was formed. The commenter also noted that there were also docket items that apparently belong in the Ceramic Tile MACT docket. The commenter stated that this raises the question of whether all brick documents are included in the docket and how industry would ever be able to know if items are missing, and also leaves concerns if these documents were meant to go into the Brick MACT docket because the EPA used it to make assumptions or if their placement was just an accident.

Commen ter 0544 listed the docket items that were at one point duplicated:

• Docket Items 121 and 221 were once the same document, but are long and verification ended up being a waste time as the document was eventually corrected.118 • Docket Items 123 and 291 were once identical

• Docket Items 125 and 220 were once identical

• There are several Clay Ceramics MACT related documents in the Brick docket. The commenter stated they assumed these were included in error since they did not see them referenced in any of the memorand a that were reviewed. If this is not in error, the commenter asked for additional time to review these items.

Following is Commenter 0544 ’ s list of items that were believed to be missing from the docket and should be added. The commenter attached copies of each to their letter.

• March 16, 2009 BIA to Jeff Telander

• September 4, 2009 BIA to Jeff Telander

• May 10, 2010 letter from Pinehall Brick to Jeff Telander

• July 1, 2010 letter from BIA to Peter Tsirigotis

• September 29, 2010 Letter from BIA to Jeffrey Teland er

• December 13, 2010 letter from members of the United States Senate to Lisa Jackson

• January 17, 2013 BIA letter to Jeff Telander

The commenter stated that the EPA inconsistently docketed items related to the SBREFA panel meetings in 2010 and 2013. For exa mple, several short emails sent after the first informal SBREFA meeting in 2010 are included in a separate docket item. The commenter noted that several items submitted after the informal SBREFA panel in 2013 are also separately docketed, however comment l etters submitted after the formal SBREFA panel are generally only included as an attachment to the final SBREFA report, rather than being listed as separate correspondence to the EPA in the docket. The commenter stated that this is not a consistent practic e, however, as at least one of the comment letters on the SBREFA process (a letter from Continental Brick) is included as both an attachment and as a separate docket item (see docket item 189). The commenter asserted that this inconsistent treatment of doc uments naturally caused them to worry that there are additional items missing from this docket.

In conclusion, Commenter 0544 asserted that the lack of organization in the docket has made a difficult task for a small association more difficult. The comment er stated that they have spent numerous hours tracking down information, verifying duplicate documents, and searching for missing items. The commenter questioned whether the docket meets the requirements of a complete docket required by law for a rulemakin g and requested that the EPA conduct a more thorough review of all correspondence and certify that the final docket is complete. If significant omissions are noted, the commenter requested that the EPA re

- open the public comment period to allow us to comme nt on the new material. The commenter also recommended that the EPA provide clear docket indices for rules to eliminate confusion and create the transparent rulemaking process that they profess to have.

Response 2: The EPA disagrees with the commenter that no docket index was available for the BSCP manufacturing NESHAP. An index can be generated at regulations.gov by first entering the docket number on the main page, opening the docket folder on the next page, selecting

“ View all documents and comments in t his Docket ” on the next page, and then selecting

“ Export. ”119 The commenter did not identify which documents in the docket they had difficulty reviewing, so it is not possible to evaluate their claim. However, the commenter should be aware that some attachments are Excel spreadsheets, which due to their size are more easily reviewed on screen in their spreadsheet form than as printouts.

With regard to the timing of materials appearing in the docket, all materials supporting the proposed rule were uplo aded to the docket by the date of publication, as required. No materials were uploaded late to the docket. However, there can be a delay from when we upload materials to the docket and when the docket office posts them to regulations.gov. With regard to th e commenter ’ s finding some duplicate items in the docket, we acknowledge there was some duplication by the docket office of some docket items, for reasons unknown.

The commenter did not identify which documents in the BSCP Manufacturing docket they think b elong to the Clay Ceramics Manufacturing docket, so it is not possible to evaluate their claim. There are some BSCP companies that include the word “ Ceramics ” in their name. However, we are certain that no BSCP docket items were accidentally placed in the Clay Ceramics Manufacturing docket and left out of the BSCP Manufacturing docket. The items included in the BSCP and Clay Ceramics Manufacturing dockets were compiled separately into different folders prior to any indexing or uploading.

We have reviewed th e list of docket items that the commenter indicated were missing from the docket. We were able to find the first three in the docket

-- under items EPA

- HQ

- OAR

- 2013

- 0291

- 0215 , 0210, and 0197

-- but we were unable to find the rest. We thank the commenter for
pro viding copies of the letters.

Concerning the commenter ’ s statement that the SBREFA panel items were docketed inconsistently, the EPA tries to avoid duplication of docket items where possible, which is why the docket items attached to the final SBREFA repor t were not duplicated in the index as separate items.

Based on a review of the missing materials, the EPA has found no significant omissions that would require re

- opening the public comment period. We thank the commenter for adding these items to the recor d as attachments to their public comment.

Comment 3: Commenter 0543 expressed concern that there are inconsistencies across the EPA ’ s supporting documentation. For example, the commenter noted that the reported number of sources potentially impacted by the regulation does not match in at least two memoranda:

• The Supporting Statement (Docket Item No. EPA

- HQ

- OAR

- 2013

- 0291

- 0129), states that there are 92 major sources and projects 25 will become synthetic area sources to avoid the MACT, leaving 67 major source s subject to the rule. The commenter stated it was not clear whether this number is referencing facilities or kilns at major source facilities.

• The memorandum Development of Cost and Emission Reduction Impacts for the BSCP NESHAP (Docket Item No. EPA

- HQ

- OA R

- 2013

- 0291

- 0117) states that there are 86 major sources and that 15 sources plus 14 stacks located at an unidentified number of sources would become synthetic area.120 In order to provide comments on the overall preamble and rule, the commenter stated that i t is important that all underlying documents consistently support the overall proposed rule and preamble. Due to these inconsistencies, the commenter requested an additional opportunity to review and comment on these memoranda once they are fixed and consi stent.

Response 3: The number of major source facilities in the Supporting Statement includes facilities with tunnel kilns and periodic kilns, as all major sources would incur some burden to comply with the rule. The number of major source facilities in th e Impacts memo excludes facilities with only periodic kilns, as those facilities would only be subject to work practice standards, which were not expected to have significant cost s

. Therefore, the two documents are working from two sets of inventory data. Regardless, both documents have been revised for promulgation, with revised facility counts. The facility counts in both documents have been reviewed for promulgation and found to be consistent. We see no need for additional review and
comment

. Comment 4: Commenter 0548 noted that the current table for Lee Brick has the control device for Kiln ID #695 listed as “ Other. ” However, the commenter stated that this kiln has never been
contr olled and should be listed as “ Uncontrolled. ”
Response 4: We c hecked the MACT floor memo

, and the control device for Lee Brick is listed

as “ None ” in Table A

- 4. The test data memo appendices also list the APCD as “ None. ” We also

c hecked the inventory memo, and the APCD column lists “ Uncontrolled ” for K iln #695

. The 2008 BIA survey results are t he only place the APCD is listed as “ Other ” for K iln #695. Therefore, we think the commenter is referring to the BIA survey summary when they say “ the current table. ” Our assessment that K iln #695 is uncontrolled is based on the April 22, 2005 stack test for this kiln, which specifies that the kiln is uncontrolled. We thank the commenter for confirming that the kiln is uncontrolled. Note: The inventory memo for proposa l listed the APCD

as “ Uncontrolled ” for all three kilns at the Lee Brick facility, but this is actually a copy

- paste error, since we only have control device information for Kiln #695. The inventory memo has been revised for promulgation to correct this er ror.