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# National Emission Standards for Hazardous Air Pollutants for Clay Ceramics 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 Clay Ceramics Manufacturing Background Information for Final Rule

Summary of Public Comments and Responses

Contract No. EP

- D

- 11

- 084 Work Assignment No. 3

- 1 2

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

................................ ................................ ........................ vi
1.0 Introduction

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

................................ ................................ ................................ ................................ ......... 2 3.0 Applicability

................................ ................................ ................................ ............................. 6 3.1 Source Category

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

................................ ................................ ................................ ................... 6 3.3 Exempt Sources

................................ ................................ ................................ .................... 7 4.0 Subcat egories

................................ ................................ ................................ .......................... 10
5.0 Method 23

................................ ................................ ................................ ............................... 11 5.1 General Opposition

................................ ................................ ................................ ............. 11 5.2 Method 23 Not Revised

................................ ................................ ................................ ...... 12 5.3 Variations in Laboratory Execution

................................ ................................ .................... 14 5.4 Validation for Ball Clay Emission Sources

................................ ................................ ........ 15 5.5 Sensitivity of Method 23

................................ ................................ ................................ ..... 19
6.0 Format of Standards

................................ ................................ ................................ ................ 20 6.1 Emission Limit Format/Units

................................ ................................ ............................. 20 6.2 Type of Standard

................................ ................................ ................................ ................. 24
7.0 MACT Floors

................................ ................................ ................................ .......................... 28 7.1 Determining Sources in Floor Pool

................................ ................................ .................... 28 7.2 UPL

................................ ................................ ................................ ................................ ..... 28 7.3 Emission Limit

................................ ................................ ................................ .................... 38 7.3.1 Manipulation of Data for MACT Floor

................................ ................................ ....... 41 7.3.2 3xRDL

................................ ................................ ................................ .......................... 47
8.0 Health

- Based Standards

................................ ................................ ................................ .......... 50 8.1 Cumulative Effects

................................ ................................ ................................ ............. 50 8.2 General Support

................................ ................................ ................................ .................. 50
9.0 Work Practice Standards

................................ ................................ ................................ ......... 51 10.0 Startup and Shutdown

................................ ................................ ................................ ........... 56
11 .0 Malfunction

................................ ................................ ................................ ........................... 65 12.0 Testing and Initial Compliance Requirements

................................ ................................ ...... 75 13.0 Continuous Compliance Requirements

................................ ................................ ................. 82 14.0 Compliance Dates

................................ ................................ ................................ ................. 94 15.0 Recordkeeping and Reporting

................................ ................................ ............................... 95 16.0 Submission of Emission Test Results (ERT)

................................ ................................ ........ 97
17.0 Definitions

................................ ................................ ................................ ............................. 98 18.0 Costs and Impacts

................................ ................................ ................................ ................. 99 19.0 Statutory and Executive Order reviews

................................ ................................ .............. 100
20.0 General Comments

................................ ................................ ................................ .............. 102
21.0 Other Comments

................................ ................................ ................................ ................. 103vi List of Acronyms and Units of Measu re

$ dollars
μg microgram
ρg picogram ACI activated carbon injection ANPR Advanced Notice of Proposed Rulemaking ANSI American National Standards Institute APCD air pollution control device ASME American Society of Mechanical Engineers Ass’n association ASTM American Society for Testing and Materials ATSDR Agency for Toxic Substances and Disease Registry BDL below detection limit BLD bag leak detection BSCP brick and structural clay products C Celsius CAA Clean Air Act CAM Compliance As surance Monitoring CBI confidential business information CEDRI Compliance and Emissions Data Reporting Interface CFR Code of Federal Regulations Cir. Circuit Court Cl 2 chlorine CMS continuous monitoring system col. column CPMS continuous parameter m onitoring system D.C. District of Columbia D/F dioxins/furans DLL detection level limited dscm dry standard cubic meter EDL estimated detection limit EMPC estimated maximum possible concentration EO Executive Order EPA U.S. Environmental Protection Agency ERT electronic r eporting t ool F Fahrenheit FCC Federal Communications Commission FR Federal Register FTIR Fourier transform infrared GACT generally available control technology HAP hazardous air pollutants HCl hydrogen chloride HCN hydroge n cyanide HF hydrogen fluoride Hg mercuryvii HMIWI Hospital/Medical/Infectious Waste Incinerators hr hour HRGC high

- resolution gas chromatography HRMS high

- resolution mass spectrometry HxCDD hexachlorodibenzo

- p

- dioxin i.e. id est (that is) ICR Informat ion Collection Request i d. idem (the same) IQA Information Quality Act ISO International Standards Organization kg kilogram L&E Locating and Estimating lb pound MACT maximum achievable control technology MDL method detection level Mg megagram mg milligram Mn manganese NACAA National Association of Clean Air Agencies NACWA National Association of Clean Water Agencies Nat’l Hational NESHAP national emission standards for hazardous air pollutants
ng nanogram NRDC Natural Resources Defense Council NSPS new source performance standard NTTAA National Technology Transfer and Advancement Act O 2 oxygen OCDF octachlorodibenzofuran OM&M O peration s , Maintenance and M onitoring OMB Office of Management and Budget PCDD Polychlorinated dibenzo

- p

- dioxins P CDF Polychlorinated dibenzofurans PM particulate matter POC products of combustion POM polycyclic organic matter PRA Paperwork Reduction Act QA quality assurance QA/QC quality assurance/quality control RDL reference detection limit RDL representati ve d etection l evel RFA Regulatory Flexibility Act SBAR Small Business Advocacy Review SBREFA Small Business Regulatory Enforcement Fairness Act SSM startup, shutdown and malfunction TCDD tetrachlorodibenzo

- p

- dioxin TCNA Tile Council of North Americaviii TEF Toxic Equivalency Factor TEQ 2,3,7,8

- TCDD toxic equivalents tpy tons per year U.S.C. United States Code UPL upper p rediction l imit

v. versus VE visible emissions WHO World Health Organization1 1.0 Introd uction

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 co ntrol technology (MACT). The EPA issued the national emission standards for hazardous air pollutants ( NESHAP ) for Clay Ceramics Manufa cturing on May 16, 2003. The NESHAP w as subsequently challenged, and the U.S. Court of Appeals for the D.C. Circuit vacate d 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, hazar dous metals, and dioxins/furans ( D / F ) from affected sources in the Clay Ceramics 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 subsequent ly 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. Public
comments on the proposed Clay Ceramics NESHAP were received from seven commenters . See www.regulations.gov

, D ocket ID N o. EPA

- HQ

- OAR

- 2013

- 0290 for the complete public comments on the Clay Ceramics 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., 0 247 , instead of EPA

- HQ

- OAR

- 2013

- 029 0

- 0 247 ).

Table 1. List of Commenters on Proposed NESHAP for Clay Ceramics Manufacturing

Document I tem No.

(EPA

- HQ

- OAR

2013

- 0290

- ) Commenter/ Title /Affiliation
0244 Michael J. Cassidy, EHS Specialist, Kohler Co.
0245 Anonymous
0246 Robert E. Hurt, Director, Environmental, Health & Safety, Dal

- Tile Corp.
0247 Howard L. Gilberg, Counsel, Guida, Slavich & Flores, P.C., on behalf of Tile Council of North America (TCNA)
0248 Nicholas Morales, Earthjustice, on behalf of Natural Resources Defense Council & Sierra Club
0249 G. Vinson Hellwig, Michigan, and Robert H. Colby, Chattanooga, Tennessee, Co

- Chairs, National Association of Clean Air Agencies (NACAA)
0250 SSM Coalition et al.2 2.0 Legal
In addition to the comments summarized and responded to below, p ublic comments on legal issues can be found in section VI.A of the preamble to the Clay Ceramics final rule.

Comment 1 : C ommenter 0247 stated that past EPA actions recognize that the agency lacks the authority to list or develop a NESHAP where the subcategory has no major sources, and provided the following information supporting their statement :

• The EPA has recognized implicitly its lack of authority to list or develop a NESHAP for an industry that has no major sources. In the 2003 now

- vacated major source NESHAP for this industry, for example, the EPA excluded the dinnerware and pottery manufacturing industries because neither subsector had a major source. In the preamble, the EPA first stated the statutory qualification criteria: “ Today ’ s final rule for clay ceramics manufacturing applies to clay ceramics manufacturing facilities that are, are located at, or are part of, a major source o f HAP emissions. ” 68 FR 26715 (May 16, 2003). The EPA then acknowledged the statutory exclusion criteria: “ The clay ceramics industry also includes dinnerware and pottery manufacturing, but these industry segments are not covered by today ’ s final rule beca use we determined that there are no dinnerware or pottery manufacturing facilities that are major sources of HAP. ” The EPA ’ s contractor explained: ” EPA defined the clay ceramics manufacturing source category to include facilities that produce pressed floor tile, pressed wall tile, other pressed tile and sanitaryware because no major sources were identified in the other segments of the clay ceramics manufacturing industry.” 1

• The EPA recognized its constitutionally and statutorily imposed limitations at the
p roposal stage of the NESHAP rulemaking proposal process. For example, in its 2002 proposed major source NESHAP for this subcategory, the EPA announced its decision to not propose major source NESHAP regulations for the clay minerals processing industry and the lightweight aggregate manufacturing industry because the EPA had determined that there were no manufacturing facilities in those industries that met the definition of a major source. 67 FR 47896 (proposed July 22, 2002).

• The EPA has declined at least eleven times to promulgate major source NESHAP for originally listed CAA Section 112(b) categories based solely on a determination that no major sources existed in them. See Chromium Chemicals Manufacturing (61 FR 28197 (June 4, 1996)); Lead Acid Battery M anufacturing ( id .); Non

- Stainless Steel Manufacturing

- Electric Arc Furnace (EAF) Operation; Stainless Steel Manufacturing

EAF Operation ( id .); Wood Treatment ( id .); Aerosol Can

- Filling Facilities (64 FR 63025 (Nov. 18, 1999)); Antimony Oxides Manufacturing ( id .); Alumina Processing (66 FR 8220

- 01 (Jan. 30, 2001)); Dry Cleaning (Petroleum Solvent) ( id .); Asphalt Concrete Manufacturing (67 FR 6521 (Feb. 12, 2002)); Uranium Hexafluoride Production ( id .); Sewage Sludge Incineration ( id .).

Response 1 : This comment incorrectly merges two aspects of section 112 and thus fails to support the comment e rs ’ position

. As discussed in more detail in the preamble, the EPA list s

1 Economic Analysis of the Clay Ceramics Manufacturing NESHAP: Final Rule, EPA

- 452/R

- 03

- 007, at page 1

- 4, EPA Office of Air Quality Planning and Standards (Feb. 2003).3 categories and source categories of major sources under section 112(c)(1), and then s ets standards for them under other provisions in section 112. It is at the point of listing that the EPA determines that a category or subcategory contains major sources. All of the examples listed by the commenter cite to discussions of whether a category or subcategory should be on the section 112(c) list ; none are examples of what the commenter is advocating here: that EPA not set standards for a subcategory that is listed. The first two examples given by the comment e r cite discussions of EPA ’ s decision not to include certain groups of sources (dinnerware and pottery manufacturing, clay minerals processing and lightweight aggregate manufacturing) as part of the clay ceramics category because those groups of sources did not include any major sources. The
t hird set of eleven examples are all examples of where EPA delisted a group of sources after EPA determined that that they contained no major sources.

Comment 2 : C ommenter 0247 noted that CAA section 112(c)(1) instructed the EPA at the outset of the 1990s NESHAP program to develop a list of categories and subcategories in which a major source was operating. The EPA’s yardstick for the designation of categories and subcategories was whether: “there is reasonable certainty that at least one stationary source in the category is a major source or where sources in the category are commonly located on the premises of major sources.” Note that the EPA’s yardstick is temporal: it required the existence of a major source in the category before a major source standard could be lawfully developed. Here there is certainty that no major source exists. The basis for deciding whether to list a category is not whether there would be a major source in the category at an indeterminate time in the future.
Response 2 : As discuss ed above and in more detail in the preamble, EPA lists categories and subcategories of major sources under section 112(c) based the information that it has at the time of the listing. Subsequently, EPA sets standards for each category and subcategory based on the listing under section 112(c). Deletions from the 112(c) list must be done consistent with the provisions of section 112(c)(9). New Jersey v. EPA, 517 F.3d 574, 581

- 583 (D.C. Cir. 2008). If a person believes that a category or source category should be deleted from the list, it may petition EPA for such deletion consistent with the provisions of section 112(c)(9)(B).

Comment 3 : C ommenter 0247 stated that the CAA NESHAP program does not authorize the EPA to regulate HAP emissions originating in mined minerals. All HAP proposed to be regulated in this NESHAP originate in, and are mined from the earth’s crust to provide raw materials for the production of ceramic tile. The EPA must heed Congress’ unambiguous instructions in the Joint Explanatory Statemen t contained in the Conference Report to the 1990 CAA Amendments: “For categories and subcategories of sources of hazardous air pollutants engaged in mining, extraction, beneficiation, and processing of nonferrous ores, concentrates, minerals, metals, and r elated in

- process materials, the Administrator shall not consider the substitution of, or other changes in, metal

- or mineral

- bearing raw materials that are used as feedstocks or materials inputs, or metal

- or mineral

- bearing materials processed or derived from such feedstocks or materials in setting emission standards, work practice standards, operating standards or other prohibitions or requirements or limitations under this section for such categories and subcategories. The prohibition in the preceding s entence shall not apply to the substitution, modification, or changes of chemicals (not including metal

- or mineral

- bearing materials) used in mining, extraction, beneficiation, or processing of nonferrous ores, concentrates, minerals, metals, and related in

- process materials which is necessary to reduce air4 emissions of such chemicals and for which substitutes that are safe and effective in performing the intended function of the chemical to be substituted are reasonably available.” H.R. Rep. No. 101

- 952 ( 1990), at 339. While this is legislative history and not statutory language, it is noteworthy that it comes from the Conference Report, which is the best form of legislative history. The commenter stated that the EPA exceeded its statutory authority by pro posing and finalizing a NESHAP for mined mineral

- based emissions.
Response 3 : The EPA disagrees that this text from the legislative history supports the
commenters ’ argument that the EPA does not have the authority to set standards for the tile subcategories. First, as the commenter notes, this is legislative history and not statutory langu age. Indeed, the “Joint Explanatory Statement” cited by the commenter carries less weight than th e Conference Committee Report

, Sierra Club v. EPA , 353 F.3d 976, 988 (D.C. Cir. 2004)

, and so is not even the most authoritative legislative history . Th is statement cannot be read to negate either EPA’s broader authority to set standards based on the MACT floor under section 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) ( i n calculating MACT floors for brick and ceramics kilns , EPA cannot ignore non

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

- technology measures affect emissions levels).

Second, the quoted text itself refers to sources “ engaged in mining, extraction, 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 ceramic tile

. The tile manufacturers covered by the tile subcategory standards are not “engaged in mining, extraction, beneficiation, and processing” of minerals.

Third, even if this statement superseded the statutory text and case law (which it does not) and if the tile manufacturers covered by this rule would fall within the scope of this text (which they do not) , th e consideration 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

.

Comment 4 : C ommenter 0247 stated that the EPA’s request fo r comment on whether to finalize the proposed NESHAP for ceramic tile manufacturing demonstrated the EPA’s self

- doubt that it has the authority to finalize standards for the ceramic tile industry.
Response 4 : The EPA disagrees that a request for comment on a matter demonstrates anything concerning the EPA’s confidence in the matter on which comment is taken. Section 307(d) of the CAA requires the EPA to publish a proposed rulemaking and provide an opportunity for public comment on that proposal

, including c omment on the underlying data, methodologies, legal interpretations, and policy considerations. Interested parties had an opportunity to comment on all aspects of this proposed rule, including on whether the EPA has authority to finalize the actions propos ed. Whether EPA explicitly requested comment on a particular aspect of the proposal has no bearing whatsoever on legal arguments regarding the scope of the EPA’s authority and in no way suggests “self

- doubt” regarding the scope of that authority.5 Comment 5 : Two commenters (0246 and 0247) argued that the CAA does not require NESHAP regulation of purported 2,3,7,8

- tetrachlorodibenzo

- p

- dioxin (TCDD) emissions from the ceramic tile subcategory because the requirements of CAA section 112(c)(6) have already been met. The commenters noted that CAA section 112(c)(6) requires the EPA to NESHAP

- regulate TCDD until “not less than 90 per centum of the aggregate emissions of [this] pollutant” has been NESHAP

- regulated. The EPA announced in the Executive Summary to its Di oxin Reassessment Report, issued February 17, 2012, that the requirements of CAA section 112(c)(6) had been met. This provision, once met, preempts the EPA’s CAA section 112(d)(3) authority to regulate purported D/F emissions from this subcategory. The pro posed D/F standard contravenes CAA section 112(c)(6) and must be withdrawn.
Response 5 : Under CAA section 112(c)(6), the EPA is required to list and then regulate categories and subcategories that account for “not less than 90 per centum” of the emissions of seven enumerated hazardous air pollutants. The plain language of this provision sets a minimum of 90 percent and does not, as commenters argued, provide that regulations are preempted if they would result in the regulation of more than 90 percent of th ese HAP. In short, while the EPA is required to get to 90 percent, it is not precluded from further regulation of these HAP after it reaches 90 percent.

Comment 6: Commenter 0248 stated that the EPA’s failure to set a standard for hydrogen cyanide (HCN) fo r Brick and Clay Ceramics violates CAA section 112. The commenter noted that the CAA mandates that EPA “shall require the maximum degree of reduction in emissions of the hazardous air pollutants subject to [section 112].” Therefore, the EPA is required to limit all hazardous air pollutants emitted from the source categories. CAA section 112(d)(2)

- (3); Nat’l Lime Ass’n v. EPA , 233 F.3d 625 (D.C. Cir. 2000). It is unlawful for EPA to not set a limit for a section 112

- 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 d eath. 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 and 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 that 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. The commenter stated, the EPA’s failure to require testing cannot excuse the EPA from 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 112(d) standards for HCN.

Response 6 : The EPA disagrees with the commenter that HCN standards must be set for coal

f ired clay ceramics kilns. In the clay ceramics manufacturing inventory, there are no kilns using coal as a fuel. All kilns use natural gas. Consequently, we were correct in not requiring the clay ceramics facilities test for HCN in the 2010 survey, and the re is no reason to require clay ceramics facilities to test for HCN in the future.6 3.0 Applicability
3.1 Source Category

Comment 1 : Commenter 0244 noted that their company is the only one in the United States affected by the proposed rule for clay ceramic s. 2 The commenter ’ s company operates three sanitaryware operations that emit area source quantities of HAP. Their company ’ s three facilities

are co

- located with major HAP sources that are separate and distinct from the sanitaryware manufacturing operations. If these three facilities were not so co

- located, they would be area sources and not subject to the proposed rule. The c ommenter stated it is important for context to understand that this rulemaking applies a major source rule to three facilities that emit only area source quantities of HAP and so do not have major source impacts on health or the environment.
Response 1 : Th e EPA appreciate s the background context from the commenter on major source applicability for the sanitaryware manufacturing sector.

3.2 Affected Sources

Comment 1: Commenter 0244 recommended the applicability of first

- fire glaze spray operations in 40 CFR 63.8540(c)(3) be clarified to state that this is for first

- fire glaze application only, and that refire glaze spray operations are not subject to this subpart. This clarification is consistent with EPA ’ s intent per the November 6, 2014 memo from RTI Inter national to EPA (Telander) titled “ MACT Floor Analysis for Clay Ceramics, ” which clearly identifies first

- fire glaze operations in Section III.

The commenter also recommended the EPA specif y how the first

- fire glaze 0.1 percent metal HAP (dry basis) thresh old is determined. The commenter asked whether it was EPA ’ s intent to evaluate percent HAP by glaze color, or by each spray booth, or across the entire facility. The commenter further asked whether the percent HAP will be based on usage for an entire year. For instance, most glazes that the commenter sprays are less than 0.1 percent metal HAP. If, due to equipment breakdown or other reason, a booth that normally only sprays glazes less than 0.1 percent HAP needs to spray a first

- fire glaze color that is gre ater than 0.1 percent HAP for one or two work shifts over the course of a year, the commenter asked whether that booth would then be subject to the MACT rule and the emissions limitations. The commenter stated that clarification is needed for sanitaryware facilities to be able to consistently determine MACT applicability for first

- fire glaze application stations. The commenter requested th e applicability be determined for each first

- fire spray booth as expressed in the November 6, 2014 memo randum from RTI I nternational to EPA and that this intent be explained in this part of the rule. HAP content should be averaged for the amount of glaze sprayed over an entire calendar year per spray booth.

Response 1: The EPA agree s with the commenter’s request and ha s rev ised the applicability criteria as suggested for the final rule.

2 See preamble sections VI.J.d and VII.A and B; Memo from RTI International t o EPA (Telander), “Development of Cost and Emission Reduction Impacts for the Clay Ceramics NESHAP,” November 6, 2014; Memo from RTI International to EPA (Telander), “Updated Inventory Database and Documentation for Clay Ceramics Proposed Rule,” November 6 , 2014; and Memo from RTI International to EPA (Telander), “Test Data Used in Clay Ceramics Proposed Rule,” November 6, 2014.7 3.3 Exempt Sources

Comment 1: Commenters 0246 and 0247 argued that, since the EPA docket contains no D/F or other HAP emissions information for any ceramic tile production process that does n ot use ball clay as its primary raw material, EPA should add an exemption to the final NESHAP stating that any ceramic tile manufacturing process that does not use ball clay as its primary raw material is not subject to any aspect of the NESHAP, including a ny D/F standard. None are an “ affected facility ” for these purposes. Commenter 0247 noted that EPA assumes that the production of pressed ceramic tile requires the use of ball clay as the primary raw material. EPA ’ s assumption may or may not be correct to day and may not be correct in the future. Without emissions information on these other possible operations, EPA ’ s proposal to regulate D/F emissions from all major sources that produce pressed tile is overly broad, and thus arbitrary and capricious.
Respon se 1: The EPA disagrees with t he commenters ’ suggest ion that we revise the rule to exempt ceramic tile processes that do not use ball clay as the primary raw material from “ any aspect of the NESHAP. ” This option is not a viable one because ceramic tile kilns are still subject to acid gas, mercury ( Hg ) , and particulate matter ( PM ) surrogate limits

. Even if EPA
were to exempt these sources from D/F emission limits , that w ould not exempt them from the limits for other pollutants or from any applicable work practice standards

. An exemption from D/F emission limits based on primary raw material would also be problematic because a testing program conducted under the 2010 section 114 survey detected D/F in most test runs at all of the ceramic tile facilities tes ted. Therefore, there is no justification for an exemption , or even a work practice standard. The commenters’ exemption request is denied.

Comment 2: Commenters 0246 and 0247 supported the proposed exemption of glaze lines that include glaze spray operations that use wet glazes containing less than 0.1 (weight) percent metal HAP (dry basis) from the definition of affected source. 40 CFR 63.8540(c)(3). Glaze lines with glaze spray operations are correctly expected by EPA to be an “ insignificant source ” of HAP emissions at major sources (79 FR 75656 (col. 1) (Dec. 18, 2014))

.

Commenters 0246 and 0247 noted that EPA reached this same conclusion i n the gene rally available control technology ( GACT ) standards for area sources in the ceramic tile manufacturing subcategory. 3 The commenters asked that EPA follow its three

- tiered area source GACT in this major source context, in addition to the exemption for speci fied wet glazes proposed in 40 CFR 63.8540(c)(3) (Dec. 18, 2014). The commenters asked that EPA to: (1) exempt glaze lines with glaze spray operations that process less than 50 tons per year (tpy) of wet clay (40 CFR 63.11435(a) (2014)) ; (2) regulate PM su rrogate emissions from glaze lines with glaze spraying operations that process more than 50 but less than 250 tons of wet clay according to the amount of non

- exempt wet glazes they process using the same workplace standards as their area

- source numeric cou nterparts (40 CFR 63.11438(c) (2014)) ; and (3) regulate glaze lines with glaze spray operations that process 250 tpy or more of non

- exempt wet glaze in the final major source NESHAP emission limits.

Commenter 0247 requested clarification of one element of the proposed wet glaze exemption. The EPA docket contains the following exchange between Kohler, a proposed member of the

3 National Emission Standards for Hazardous Air Pollutants for Clay Ceramics Manufacturing Area Sources, 40 CFR Part 63, Subpart R RRRRR (2014)8 NESHAP sanitaryware subcategory, and EPA dated December 11, 2014 regarding the scope of this proposed exemption: [Kohler:] “ Spray booth emission limits: Proposed limits apply to spray booths using only if glaze containing >0.1% metal HAP. Is this an average of glaze used in a booth or does it apply to any color? For instance, most of thei r glazes are <0.1% HAP. If due to equipm ent breakdown or other reason a facility needs to spray some glaze color that contains >0.1% in a booth for 1 work shift, say once per year, does this make this booth subject to the MACT rule and the emission limitation? ” [EPA Response:] “ The 0.1% metal HA P is an average of glaze used in a booth, and would include all colors used in that booth. The average would be on an annual basis, consistent with the information requested in the section 114 survey. We will clarify this in the final rule. Since it would be an annual basis, spraying a glaze color with >0.1% metal HAP for just 1 work shift would not be enough on an annual basis to make this booth subject to the MACT rule and emission limitation. ” Commenter 0247 concurred with EPA ’ s response to Kohler and re quested EPA likewise confirm th is statement in the final NESHAP for the ceramic tile manufacturing subcategory and c larity the applicability criteria in the relevant portion of th e preamble to the final rule

. Response 2: The EPA appreciates the commenters’ support for the exemption of glaze spray operations that use wet glazes containing less than 0.1 (weight) percent metal HAP (dry basis). However, the EPA disagrees with the commenters’ request that we implement the GACT provisions from the Clay Ceramics a rea source NESHAP. First, the area source NESHAP is authorized under CAA section 112(d)(5), and its provisions are not applicable to the major sources in this rule regulated under CAA section 112(d)(3). Second, the commenters have misinterpreted the provis ions in que stion. T he first provision, cited as 40 CFR 63.11435(a)

, exempted clay ceramics manufacturing facilities, not glaze lines , as the commenters reported

. Regarding t he second provision, the commenters appear to have mistakenly combined two differen t thresholds

-- 50 tpy of wet clay in 40 CFR 63.11435(a) and 250 tpy of wet glaze(s) from 40 CFR 63.11438(c) to create a new threshold of 50

- 250 tpy of wet clay.
The EPA agrees with Commenter 0247’s interpretation of our response concerning the wet glaze

exe mption. We have revised the regulatory text in the final rule to clarify the exemption.

Comment 3: Commenter 0244 requested clarification of refire kiln applicability in 40 CFR 63.8540(c)(1). While the commenter almost exclusively uses shuttle kilns to re fire ware, some shuttle kilns may be permitted for first

- fire ware as an operational contingency in the event of a first

- fire tunnel kiln malfunction. Though permitted as such, these refire kilns have likely never processed a first

- fire batch of ware. The commenter asked EPA whether the fact that a shuttle kiln is permitted for first

- fire ware makes it subject to the rule, even though it likely has never processed first

- fire ware. Similarly, if a circumstance arises in which a shuttle kiln does fire a batch of first

- fire ware, the commenter asked whether it is now subject to the clay ceramics MACT rule. The commenter asserted that firing a single batch of first

- fire ware every few years should not subject that kiln to the rule, and suggested that a “ frequenc y of use ” delineator or threshold should be included in this section for determining rule applicability. The commenter proposed that any refire shuttle kiln firing 4 batches/year or less of first

- fire ware be excluded from rule applicability. Firing the eq uivalent of one batch of first

- fire ware per calendar quarter, as an average, is an inconsequentially small quantity of emissions that should not trigger MACT applicability. Records of first

- fire ware processing will be kept for applicability determination
purposes.9 Response 3: The EPA cannot grant the requested exemption for refire shuttle kilns firing four batches/year or less of first

- fire ware. The commenter has not provided the necessary data to substantiate their claim that firing four batches of firs t

- fire ware would result in an inconsequentially small quantity of emissions.

Comment 4: Commenters 0246 and 0247 supported the following exclusions from the definition of “ affected facility ” proposed in 40 CFR 63.8540(c)(1)

- (5) ( 79 FR 75694 (col. 1)(Dec. 18, 2014) : (1) Kilns that are used exclusively for refiring; (2) kilns that are used exclusively for setting glazes on previously fired products; (3) glaze spray operations that use wet glazes containing less than 0.1 (weight) percent metal HAP (dry basis) ; (4) raw material processing and handling; and (5) wall tile press dryers.
Response 4: The EPA appreciate s the commenters’ support for the applicability criteria in the proposed rule and direct s the commenters’ attention to additional clarifications to th e criteria that have been made for the final rule in response to other public comments

.10 4.0 Subcategories

Comment 1: Commenters 0246 and 0247 supported the subcategorization of ceramic floor tile manufacturing

, ceramic wall tile manufacturing

, and sanit aryware manufacturing.
Response 1: The EPA appreciate s the commenters’ support. As noted in the proposal preamble,

“ based on our review of the available information on the clay ceramics manufacturing industry, we determined that there are three distinct se ctors within the industry: (1) Ceramic floor tile; (2) ceramic wall tile; and (3) sanitaryware. Specifically, the EPA found that the ceramic floor tile, ceramic wall tile and sanitaryware sectors of the industry differ in terms of raw materials,
processes and final products. ” (79 FR 75655) It should be noted that th e determination of these industry sectors is distinct from our subcategorization of the industry sectors, which include s two subcategories for sanitaryware kilns

-- (1) sanitaryware periodic (shuttle) kilns and (2) sanitaryware continuous (tunnel) kilns; and three subcategories for sanitaryware glazing

-- (1) manual glaze spraying, (2) spray machine ( or chain

- on

- edge ) glaze application, and (3) robot glaze spraying.11 5.0 Method 23

5.1 General Opposition

Comment 1 : Commenters 0246 and 0247 o ppos ed the p roposed D/F standard . The commenters argued that EPA ’ s proposed D/F standard is arbitrary and capricious because it is not supported by scientifically and legally valid D/F emissions data. The com menters also noted that mass emissions of 2,3,7,8

- TCDD toxic equivalents ( TEQ ) from all ceramic tile manufacturing sources in the EPA docket are less than 3.5 grams per year and remarked that this is a miniscule amount dispersed over a huge area. The comme nters strongly question ed the validity of the emissions data and EPA ’ s right to regulate D/F emissions without a validated stack testing method

. The commenters asserted that n o judicial precedent supports regulating theoretical D/F emissions from this subcategory and challenged the EPA ’ s legal authority to continue wit h regulat ing D/F emissions from this sector

.

C ommenter 0247 noted that EPA ’ s basis for the proposed D/F standard is CAA Section 112(d)(3)(B), which requires emissions standards to be based on: “ 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 ... ” . The commenter stated that to set q uantitative emission standards, emissions information must be scientifically valid, quantitative data. The commenter objected to the D/F standard for the ceramic tile manufacturing subcategory because they claim Method 23 is incapable of producing accurate data for a MACT standard. Without this foundation, the commenter asserted, the proposed D/F standard must be withdrawn as arbitrary and capricious.

The commenter noted that the ceramic tile manufacturing industry conducted stack testing to

measure D/F emissions using Method 23 in response to a March 2010 EPA Information Collection Request (ICR). The results of that stack testing provide the only quantitative D/F information in the docket supporting the proposed D/F standard. However, the commenter
argu ed the Method 23 has never been validated for the ball clay matrix found in the ceramic tile manufacturing industry, and cannot be followed, as it is written. The companies that received the ICR went to great expense to comply and engaged a well

- respected companies with stack testing and laboratory experience with specific Method 23. However, the commenter asserted that Method 23 does not generate scientifically valid data usable for the development of a MACT standard. Method 23 was designed and validated a t a time when biogenic D/F encapsulated in a solid ball clay matrix was not known. The EPA ’ s Method 23 validation focused on anthropogenic D/F in a gaseous media as the only known D/F source at the time of the method

was development.

The commenter noted th at biogenic dioxin encapsulated in ball clay was discovered in Mississippi in 1996. Many types of ball clay do not contain D/F , but when it is present, it is encapsulated within highly charged clay platelets in a ball clay matrix. The commenter argued that t hese strong bonds severely limit the environmental availability of dioxin. They further noted that Method 23 was developed almost two decades before th is 1996 discovery and the method was based on the analytical requirements from the 30

- year old EPA Meth od 8290. Its clean

- up procedures date back to 1974. The commenters asserted that Method 23 cannot be validated as currently written for ball clay because it cannot distinguish between free dioxin and12 dioxin that is bound and encapsulated as a particulate i n the ball clay matrix and therefore, not environmentally available.

Response 1 : The EPA disagrees with the general comment that the proposed MACT dioxin and furan standard is without factual support. We have provided specific responses to individual

comme nts on the validity of stack testing methodology and data used to measure dioxin and furan concentration in stationary source stack emissions later in this section. We proposed limits to emissions for these classes of hazardous air pollutants based on empi rical data collected from potential emission source(s) for these compound classes in this source category. We take exception and disagree with the statement that 3.5 grams per year of chlorinated dibenzo(p)dioxin and chlorinated dibenzofuran emissions are insignificant since the regulatory mandate in the CAA of 1990 (CAA) for Title III hazardous air pollutants are based on the demonstrated ability to control the target pollutant and EPA is obligated under the CAA to set limits based on data demonstrating th e performance of sources in specific source categories. Our mandate to regulate in the CAA is not based on absolute mass of the emissions but rather on

1. the ability to control those emissions, 2. the emissions originate predominantly from a small number of sou rces and 3. the environmental effects of the chlorinated dioxin and furan classes of compounds are significant at low concentration.

While we do not dispute that there may be differences in the implementation of Method 23 among specialty laboratories perfor ming analysis for dioxins and furans, EPA asserts that the quality control inherent in the method provides adequate support for the validity and accuracy of the emission results.

We also disagree with comments about the validity of the test method used to determine chlorinated dioxin and furan emissions from this source category. Such a general statement that the chlorinated dioxin and furan classes emitted as particulate bound or gaseous hazardous air pollutants from stationary sources in the category are different from other stationary source categories where Method 23 has been successfully implemented is without merit and the commenter provides no data to support this claim. The same method requirements regarding the recovery of isotopically labeled diox in and furan congeners apply for evaluating the validity of data for this source as they would be from any other air emission source. Review of the data submitted by the industry through the ICR process provides adequate information to determine that the r ecovery of labeled dioxin and furan congeners met method requirements and that the analysis of said samples generated valid data on emission concentration.

5.2 Method 23 N ot R evised

Comment 1 : Commenter 0247 argued that Method 23 h as n ot b een revised and i s , t herefore

, n ot

v alid

. The c ommenter noted that standards developed by the American Society for Testing and Materials (ASTM), American National Standards Institute (ANSI), and the International Standards Organization (ISO) are require d to be periodicall y revised, reaffirmed, or withdrawn. Typically, the review process is required at least once every 5 years. The Information Quality Act, 44 U.S.C. 3501

- 3520, requires the EPA to review its methods. EPA ’ s stack testing methods13 experts are among those at EPA that hold memberships in these consensus standards

- setting organizations, and actively support their approaches and work.

The commenter stated that the EPA

, the private sector, and academ ia know Method 23 has problems. EPA had prioritized a broad rewriti ng of Method 23 in 2007, but to date EPA has failed to update the method

. The commenter asserted that EPA has had ongoing knowledge and has worked to rectify issues with Method 23. T he E PA first used Method 23 to measure D/F emissions from the ball clay ma trix in mid

- 2003 and , according to the commenter, the EPA realized at that time the unique challenges presented by the ball clay matrix. In 2009, the commenter stated the EPA initiated discussions with experts i n the field of dioxin stack measurement, incl uding Dr. Yves Tondeur, a principal author of Method 8290 and principal contributor to Method 23. Commenter 0247 stated that Dr. Tondeur developed and presented EPA with a major rewrite of Method 23, which was discussed at the public Source Evaluation Soci ety conference in Arizona in 2011. A substantial EPA contingent met in Wilmington, North Carolina in 2013 with Dr. Tondeur and other members of the dioxin measurement community with the goal of moving forward with drafting a new dioxin measurement method ( proposed EPA Method 8223) and revising the analytical portion of Method 23. Dr. Raymond Merrill, EPA Director of Methods Development delivered an internal presentation titled “ What You Always Wanted to Know About EMPC But Were Afraid to Ask ” at the internal EPA Measurement Technology Workshop in 2013. The commenter asserted that these facts establish that the EPA has been well aware of long

- standing inaccuracies and problems with Method 23 , and believes that since Method 23 was not revised, i t is not valid.

According to the commenter, public presentations by EPA ’ s dioxin policy and Method 23 experts also confirm that Method 23 is deeply flawed. The commenter also alleged that EPA staff acknowledge that no two analytical labs run Method 23 the same way or as required by the Method because of these flaws. The commenter stated the EPA has informally solicited those in private industry that it deems knowledgeable in this field, including its own certified contractors, seeking input and suggestions on how to rewrite Method 23. The commenter also stated that segments of the private stack testing industry and academics share these and other concerns. They also stated that the EPA is aware that the equipment, materials and processes specified for Method 23 have been replaced by more accurate technology , but note they have not been validated for Method 23 or for Method 23 use d to measure D/F in ball clay. The commenter alleged that Method 23 requires outdated equipment, materials, and processes, including some equipment have not been available for many years. If Method 23 was an ANSI, ASTM or ISO standard, the commenter noted it would have been updated multiple times since its initial issuance or withdrawn. The commenter stated that EPA ’ s failure to update Method 23 for known problems “ is alarming and egregious. ”

The c ommenter stated that while Method 23 is EPA ’ s only and thus “ best ” D/F air quality measurement tool

, it does not mean the D/F data submitted by the industry in response to EPA’s March 2010 ICR is scientifically valid or legally usable. The commenter understand s the EPA plans to issu e in late 2015 or 2016 an Advanced Notice of Proposed Rulemaking (ANPR) associated with a Method 23 rewrite that will include the ball clay matrix. The commenter sta ted the EPA first used Method 23 in an attempt to measure D/F emissions from the ball clay matrix14 in mid

- 2003 , and argued the EPA has had over eleven years to revise Method 23 and has failed to do so. Th e commenter argued that this ANPR is a required first step.

The commenter noted the EPA has issued guidance on category

- and subcategory

- specific patches for Method 23 that acknowledg e the flaws in Method 23, 4 and have issued NESHAP reflecting stack testing results generated by a modified Method 23. EPA has failed to do so for the ceramic tile manufacturing subcategory, the commenter contends, because EPA knows the method has not been validated for the ball clay matrix in this subcategory and that patches presume the method has been validated and need s only “ tweaks ” to provide data usable for regulatory purposes. Patches and other guidance have no legal effect because they have not been subject to the same Administrative Procedures Act process, including notice and comment, to which current EPA test methods ar e subject. The commenter alleged that n one of the other industry

- related changes or anything else in Method 23 address and resolve the issues specific to the ball clay matrix found in the ceramic tile manufacturing industry

.

The commenter further stated th at CAA section 112 deadline for EPA to issue the proposed NESHAP does not provide EPA authority to use results from test method s that ha ve not been validated to be “ emissions information ” as that term is used in CAA section 112(d)(3). The
commenter asserted the EPA must withdraw its proposed D/F standard for this subcategory because it is not based on “ emissions information. ”

Response 1 : The EPA disagrees with the fundamental tenant that a method is invalid on the grounds that it has not been revised or updated. When Method 23 is used to measure air emissions of chlorinated dioxins and furans from stationary source, the results from those tests are as valid today as they were when the method was first promulgated. It is true that improvements to all m easurement method evolve over time as experience grows using the method. Furthermore, facilities certified that the data was accurate and complete for the ICR process. As EPA reviews data from various ICR campaigns, variations in laboratory procedure that were documented in test reports were shown to be improvements to the existing Method 23 procedure making the data valid and useful for its purpose in the ICR.

5.3 Variations in Laboratory Execution

Comment 1 : Commenter 0247 argued that Method 23 d ata u sed to generate the MACT f loor a re

n ot v alid d ue to v ariations in l aboratory e xecution

. The c ommenter cite d flaws in Method 23 in the following areas:

1. AX

- 21 Activated Carbon 2. Methylene Chloride and Toluene Residual Quality Control 3. Verification 4. Benzene Usage 5. Chromic Acid Glass Soaking/Cleaning 6. Glass Cleaning Generally 7. Packed Columns

4 See (ALT

- 034) Approved Modifications to Method 23 for Secondary Aluminum Facilities, (ALT

- 036) Approval of Method 23 Modifications for Cement Kilns, (ALT

- 052) Approved Method 23 Modifications for Incinerators and Waste Combustors, and (ALT

- 065) Approval o f Methods 23 and 320 for 40 CFR part 63, subpart EEE.15 8. Gravity Column Chromatography Efficiency 9. Ion Mass Interferences/Coelutants

a. Molecular Interferences b. Ion Fragment Interferences 10. Precision and B ias 11. Comparison of Method 23 to Globally Recognized Standards for Scientific Reliability and Accuracy
Response 1 : Method 23 is a self

- validating method. The compounds that are on the list of required targets for this method have unique physical and chem ical properties. Implementation of Method 23 by each test team is evaluated against the recovery of isotopically labeled standards. The sampling media, XAD

- 2®, is spiked before it is used to collect stack gas samples. Samples are also spiked with isotopica lly labeled standards when they are prepared in the analysis laboratory to evaluate the extraction and preparation of the samples for analysis. If the spike recoveries are within the method specifications and other method quality control was met for the me thod, the data are considered valid. While EPA agrees Method 23 could be improved with modifications, EPA’s ongoing effort to update Method 23 does not invalidate the data that was collected from stack tests in 2010.

5. 4 V alidat ion for B all C lay E mission S ources

Comment 1 : Commenter 0246 and 0247 argued that Method 23 h as not been v alidated

s pecifically for b all c lay e mission s ources

. C ommenter 0247 alleged the EPA issu ed the March 2010 ICR with prior knowledge of the limitations of Method 23. Given EPA ’ s documented knowledge that Method 23 had not been validated for the ball clay matrix, along with the numerous limitations of the method, specifying its use for the 2010 ICR was egregious, extremely costly, scientifically flawed, and arbitrary and capricio us. The commenter alleged that some segment of EPA initiated this regulatory development process with a conclusion that D/F emissions might, or do, arise from the ball clay matrix used in the ceramic tile manufacturing industry, and then other segments wor ked backward to find D/F results using Method 23 to validate that conclusion. The commenter stated that using a test method that “ lacked validation to come to any conclusions in that context is unquestionably arbitrary and capricious ” and argued the EPA is obligated to withdraw the proposed D/F standard

. EPA should have develop ed and validate d a D/F stack testing method for biogenic, encapsulated D/F in the ball clay matrix before beginning this rulemaking . Only after it has a validated D/F method for the s olid ball clay matrix that encapsulates D/F , if it is present, is EPA legally permitted to proceed with an ICR and develop a D/F standard for the ceramic tile manufacturing subcategory.

Commenter 0247 claimed Method 23 is flawed in at least 17 ways and arg ued that any one of these flaws are legally sufficient to draw the conclusion that the proposed D/F standard is arbitrary and capricious and must be withdrawn. The ceramic tile manufacturing industry should have been advised by EPA of the problems with Met hod 23 prior to the ICR testing . The ceramic tile manufacturing industry learned after completion of the ICR

- mandated stack testing that several requirements of Method 23 are impossible to satisfy. These problems render the emissions data collected by indu stry unusable for this or any other regulatory purpose ; they are16 scientifically invalid, their accuracy is uncertain, and their legal eligibility for use in the development of a proposed D/F Standard for this industry has been voided. 5

Commenter 0247 note d a number of alleged failures in Method 23 applicable to the ceramic tile manufacturing industry and the ball clay matrix

, including:

1. Method 23 Has Not Been Validated for Use in the Biogenic Ball Clay Matrix 2. EPA ’ s Validation of Method 23 for Municipal Waste Combustors Does Not Carry Over to Ceramic Tile Manufacturing Sources 3. Method 23 Sample Gathering and Laboratory Handling Requirements Further Compromise the Validity of the Emissions “ Data ” Used by EPA to Support its MACT D/F Emissions Li mits

a. The Heated Method 23 Filter Alters the Solid Stack Gas Sample, So Method 23 Emission Data Do Not Reflect Actual D/F Stack Emissions b. Soxhlet Extraction is Accretive to the Unreliability of D/F Emissions Information 4. Moisture Removal Requirements 5. Absence of Recovery Methodology 6. Field Surrogates
Response 1 : The EPA disagrees with the conclusion that the Method 23 is incapable of generating scientifically valid data. M ethod 23 has been v alidated in previous test s and will be valida ted every time a source test is conducted as long as the recoveries of the spiked sample media m eet the recovery criteria in the m ethod. Method 23 as originally written and in all of the variations documented in the ICR results requires labeled isotope spi kes to determine the recovery of the target compound classes for this method. Isotopic label recovery as previously noted in this response to comment validates the sampling and chemical procedures to generate results within acceptable performance requireme nts. Our review of the ICR data showed that the recovery of isotopically labeled compounds used as quality checks of Method 23 performance for samples from ceramic tile exhaust were within acceptable limits for data submitted in response to the ICR. Subseq uent procedures to normalize the analysis data for recovery of is o topically labeled standards used in sample extraction and preparation were performed and correctly used to generate valid laboratory data. M ethod 23 validation for clay ball matrix occurred with the ICR test data and past method 23 test results that met the recovery standard requirements of the method

. These recoveries are presented in the following table.

Dioxin/ f urans were present in tests conducted on the ceramic tile exhaust. Me thod 23 has been used and proven to give valid data for particle bound and gaseous chlorinated dioxins and furans in several source categories including Hospital/Medical/Infectious Waste Incinerators ( HMIWI ) and Portland Cement MACT. While the method has r oom for improvement and the EPA is working on updating Method 23, the need for improvement does not invalidate the data that was collected from stack tests in 2010. Furthermore, the commenter provides no data to demonstrate their conclusion that Method 23 results as implemented by testing teams are less valid than the

5 This comment includes a non

- exclusive list and associated discussion of Method 23 flaws, omissions and issues. Commenter 0247 highlighted the most material of these as applied to the ceramic tile manu facturing industry. The commenter stated that each flaw, omission and issue in and of itself is sufficient basis to reject the data used by EPA to develop a MACT D/F floor, and to reject the proposed D/F standard.17 results generated by the method run as written. In fact, EPA asserts, testing teams that employed improvements including substitution for materials or supplies that were not available to them at the time of testing demonstrated results of equal or better validity, as demonstrated by isotopic labeled spike recovery

, than the requirements in Me thod 23 as written. We provide T able 1 as an example from ICR results to demonstrate labeled spike recov ery

. Commenters should note that modification requests to Method 23 during the ICRs have been granted to include the following:

Laboratory does not use silica gel in the soxhlet apparatus.

• All provided solvent rinses are combined, concentrated, and added t o the resin/filter components before soxhlet extraction.

• Prior to cleanup, the extract is dried with sodium sulfate and Cleanup Recovery Standard is added.

• The extract is split for archival. Tetradecane is added to the remaining half and the extract is con centrated to the tetradecane.

• The extract undergoes Acid/Base Silica Gel column and Florisil column cleanup. Basic Alumina and AX

- 21 Carbon/Celite 545 Columns are not used.

• After cleanup, the eluate is concentrated, added to a conical vial containing tetra decane and Recovery Standard Solution, and concentrated again to a final volume of 20:l.

• The internal standard mix includes 13C

- OCDF. The concentration of the 13C

- OCDF is 200pg:l. OCDF is quantified against 13C

- OCDF.

• The Initial Calibration curve include s six levels; the concentration of the lowest level is
at one

- half the low point of the curve in Table 2 of Method 23.

• Addition to Table 4 of Method 23 for CDD only:

o Number of Cl 2 Atoms

– 5

o Ion Type

– M+2/M+4

o Theoretical Ratio

– 0.65

o Lower Control Limit

– 0.55

o Upper Control Limit

– 0.7518 Table 1 ( generated from data in EPA

- HQ

- OAR

- 2013

- 0290

- 0069 )
Field Spike Standards L924489

- 1* % Recovery L924489

- 2 % Recovery L924489

- 3 % Recovery L924489

- 4 % Recovery
37Cl4

- 2,3,7,8

- TCDD 94 91 94 91
13C12

- 1,2,3,4,7,8

- HxCDD 97 121 82 104
13C12

- 2,3,4,7,8

- PeCDF 101 100 97 92
13C12

- 1,2,3,4,7,8

- HxCDF 96 94 73 98
13C12

- 1,2,3,4,7,8,9

- HpCDF 94 89 94 89 Field Spike Standards L924489

- 6 % Recovery L924489

- 7 % Recovery L924489

- 8 % Recovery L924489

- 9 % Recovery
37Cl4

- 2,3,7,8

- TCDD 93 92 89 93
13C12

- 1,2,3,4,7,8

- HxCDD 88 76 103 106
13C12

- 2,3,4,7,8

- PeCDF 91 95 101 106
13C12

- 1,2,3,4,7,8

- HxCDF 91 95 86 96
13C12

- 1,2,3,4,7,8,9

- HpCDF 102 112 98 107 Field Spike Standards L924489

- 10 % Recovery L924489

- 11 % Recovery L924489

- 12 % Recovery L924489

- 13 % Recovery
37Cl4

- 2,3,7,8

- TCDD 77 87 88 89
13C12

- 1,2,3,4,7,8

- HxCDD 89 96 127 99
13C12

- 2,3,4,7,8

- PeCDF 67 75 71 104
13C12

- 1,2,3,4,7,8

- HxCDF 86 89 79 115
13C12

- 1,2,3,4,7,8,9

- HpCDF 93 88 88 98 Field Spike Standards L924489

- 14 % Recovery L924489

- 15 % Recovery L924489

- 16 % Recovery L924489

- 17 % Recovery
37Cl4

- 2,3,7,8

- TCDD 89 91 105 105
13C12

- 1,2,3,4,7,8

- HxCDD 99 118 103 102
13C12

- 2,3,4,7,8

- PeCDF 104 99 118 115
13C12

- 1,2,3,4,7,8

- HxCDF 115 83 91 87
13C12

- 1,2,3,4,7,8,9

- HpCDF 98 103 103 107 Field Spike Standards L924489

- 18 % Recovery L924489

- 19 % Recovery
37Cl4

- 2,3,7,8

- TCDD 99 99
13C12

- 1,2,3,4,7,8

- HxCDD 90 103
13C12

- 2,3,4,7,8

- PeCDF 110 108
13C12

- 1,2,3,4,7,8

- HxCDF 86 89
13C12

- 1,2,3,4,7,8,9

- HpCDF 102 107
*Method Blank Train 1 was not spiked with field spike Standards19 5. 5 Sensitivity of Method 23

Comment 1 : Commente r 0247 argued that Method 23 is n ot s ensitive e nough to m easure the

c oncentration of chlorinated d ioxins and f urans at the level of the s tandard

. The EPA MACT floor calculations are at picogram ( ρg ) levels that require laboratory measurement quantification limits below calibration ranges for the high

- resolution gas chromatography and high

- resolution

ma ss spectrometry ( HRGC/HRMS ) equipment specified by Method 23. Commenter 0 2 47 was concerned because two of the proposed D/F emission standards are based on measurements below the r eference detection l imit (RDL)

. S cien tists ha ve devoted a great deal of atten tion to detection limits, and adherence to set quantification limits that have a strong statistical confidence in measured amounts of individual D/F analytes is necessary

. The commenter was also troubled by t he use of estimated maximum possible concentrati ons ( EMPCs ) and qualified emissions information measured at below detection limits and noted that Method 23 is completely silent on these important data quality issues.
Response 1 : EPA disagrees with the commenter’s conclusion that the detection limit capa bilities of their chosen test contractor were inadequate to justify the MACT floor calculations at picogram levels. Method 23 defines the detection limit as an estimated detection limit or “EDL”. The test contractor reported EDL in the range of 1.4 to 7.1 ρg. Quantitative limits based on these EDL could be estimated worst case of approximately 21 ρg for any target chlorinated dioxin or furan. (Compared to a Utility RDL laboratory community average of 77ρg by mass or 9 ρg by TEQ )

.

If there are errors associa ted with the extraction and recovery of the samples from the stack, EPA believes that the calculation of the floor by the upper predictive limit (UPL) takes into account these errors and general variability in the process of achieving detectable measuremen ts. Thus to ensure the process and measurement variability is adequately addressed when there are undetectable measurements, we compare the upper prediction limit ( UPL ) against three times the representative detection level (3 x RDL ). If the floor is less than three times the RDL , we adjust the floor level to three times the RDL . The dioxin and furan data was above the detection limit, so adjusting to the RDL was not necessary. However, we account for measurement variability via the use of the UPL, which was used to set the floor, and not 3 x RDL.20 6.0 Format of Standards

6.1 Emission Limit Format/Units

One significant public comment on emission limit format can be found in section V.C.2 of the preamble to the Clay Ceramics Manufacturing final rule. The remaining public comments and the EPA’s responses are presented in this section.

Comment 1 : Commenter 0247 challenged the Toxic Equivalency Factors (TEF) proposed in Table 5 [79 FR 75709 (Dec. 18, 2014)(proposed to be codified as Table 5 of 40 CFR 63, subpart KKKKK)] because those values do not follow EPA ’ s Recommended Toxicity Equivalence Factors (TEFs) for Human Health Risk Assessments of 2,3,7,8

- Tetrachlorodibenzop

- dioxin and Dioxin

- Like Compounds. [Risk Assessment Forum, EP A/600/R

- 10/005, U.S. EPA (2010)] According to the commenter, the proposed Table 5 reflects World Health Organization ( WHO ) 2005 TEF values. The commenter stated that EPA offered no explanation or justification for ignoring its own values published in 2010 in its arbitrary selection of the WHO 2005 values.
Response 1 : The EPA disagrees with the commenter that we did not use the recommended TEFs for dioxin/furan congeners in th e Clay Ceramics proposed rule. We attempted to find the EPA/600/R

- 10/005 document t hat the commenter reference s , but could only find the EPA/100/R

- 10/005 version , which is in the docket for the Clay Ceramics Manufacturing rule

. The citation from the commenter (EPA/600/R

- 10/005) is provided at the bottom of the Abstract in the EPA document, which is different from the citation on the cover page of the EPA document (EPA/100/R

- 10/005). This may explain the discrepancy. Regardless, t he EPA document in question recommended the use of the WHO 2005 TEF values (see Abstract). The TEF v alues listed in Table 2 of the EPA document are the same TE F values listed in Table 5 of the proposed rule

. Comment 2 : Commenter 0244 contended that the sa nitaryware kiln emission limits in Table 1 to the proposed rule should apply to each kiln ’ s POC (products of combustion) stack only. The commenter requested that this be stated in the table and elsewhere in the rule. Tunnel kilns are designed with a primar y exhaust stack in the front part of the kiln and with 2 or 3 auxiliary stacks used for ware cooling in the back half of the kiln. The primary exhaust stack discharges the products from combustion of natural gas, plus the vitrifying zone atmosphere contain ing the HAP emitted from the ware (i.e. HF). The cooling stacks essentially exhaust ambient air used for ware cooling in the kiln. Air movement (draft) in a tunnel kiln combustion section is always maintained in the direction of the POC stack to maintain p roper operating pressures in the pre

heat and vitrification zones. This means air moves from the end of the vitrification zone (middle of the kiln) toward the POC stack exhaust point. Proper draft maintains proper pressure in the kiln, which is key to prop er kiln operation and minimiz es scrap and fuel use. Tunnel kilns are designed and operated to restrict air flow from the vitrifying zone towards the cooling zone. Some tunnel kilns even have brick baffles on the downstream end of the vitrifying zone to inh ibit air flow into the ware cooling section. Th is design accomplishes two goals: (1) i t maximizes ware yield by eliminating multiple potential ware defects that are created by vitrifying zone atmosphere contacting vitrified ware; and (2) i t minimizes heat loss and fuel use (operating costs).21 According to the commenter, this issue was addressed with EPA during the ICR testing process when all cooling exhaust stacks on all kilns were screened for oxygen ( O 2 ) content. If the O 2 content measured 20.4 percent or higher, the stack was considered to essentially exhaust ambient air and no ICR testing was required. The cooling exhaust stacks on all tunnel kilns, except Spartanburg SC tunnel kiln 10, had O 2 concentrations greater than 20.4 percent and so
were not test ed under the ICR test program in accordance with a prior agreement with EPA. These results are included in the test reports submitted to EPA. The O 2 concentration in the TK10 cooling exhaust stack measured between 20.0 and 20.4 percent . For reference, the commenter indicated this was the kiln in which EPA forced the restart of the shutdown wet scrubber for ICR testing. As this was not how this existing kiln operated, and the scrubber had been shut down for the prior 17 months and only restarted days before the ICR testing, the commenter indicated it was likely that use of the scrubber for the short time the emissions testing took place affected normal airflow through and pressures in the kiln, which may not have been properly stabilized for ICR testing and p ossibly forc ed vitrifying zone atmosphere into the cooling zone.

If EPA does not find the commenter ’ s request acceptable, the commenter stated that EPA must clarify specific stack applicability criteria, as testing for the regulated HAP is very expensive, and requiring the testing on stacks exhausting ambient air is a very unreasonable burden to place on any sanitaryware facility, especially when these tunnel kilns have already been shown to only emit HAP in area source quantities (see Table 8 in the Novemb er 6, 2014 memo from RTI International to EPA titled “ Development of Cost and Emission Reduction Impacts for the Clay Ceramics NESHAP ” ).
Response 2 : W ith one small exception, the EPA agree s with the commenter’s understanding of the issue and ha s revised th e testing provisions for the final rule to clarify that stacks to be tested at sanitaryware manufacturing facilities are to be limited to POC stacks and those cooling stacks with an oxygen content at or below 20.5 percent. However, t he EPA’s review of the testing agreement indicates that an oxygen content of 20.5 percent, rather than 20.4 percent, was the threshold for testing.

Comment 3 : Commenter 0244 supported using PM as a surrogate parameter for non

- Hg HAP from tunnel kilns in the sanitaryware subcateg ory.

Commenter 0247 proposed that the ceramic tile subcategory be allowed to demonstrate compliance using the currently proposed PM surrogate limit

, a new total non

- Hg HAP limit , or

new metal

- by

- HAP metal emission limits. The commenter contended that limi ting the ceramic tile subcategory to a PM surrogate standard unnecessarily limits the flexibility of the industry to comply.

According to Commenter 0247, EPA ’ s decision to not provide this flexibility was questioned during the Interagency Review pursuant t o Executive Order 12866. Interagency Commenter asked “ For the BSCP source category, EPA explained that some owners/operators may find that meeting a total non

- Hg HAP metals limit is less costly than meeting a PM limit and provided that flexibility of using an alternative compliance option for total non

- Hg HAP metals. Does EPA have reason to believe that would not be the case for this source category? Or is there some other reason why EPA is only providing the option of meeting the PM standard as a surrogate for22 non

- Hg HAP metals? ” The EPA r esponde d by saying “ We do not have the data needed to establish an alternative non

- Hg HAP metals numerical limit for the clay ceramics source category. ” 6 The commenter stated EPA never identified in writing what data it lacked and argued that EPA ’ s dismissal of this question failed to satisfy its obligations under this and other Executive Orders. According to the commenter, the only remedy for this failure is for EPA to reinitiate this rulemaking and for EPA to discharge its legal obligations by providing a substantive respons e.

Commenter 0247 believed the EPA’s decision not to adopt individual metal HAP limits was due to issues related to the manganese (Mn) . The commenter noted the EPA rejected some of the industry ’ s Mn floor tile kiln and glaze line stack testing emissions re sults because of Mn contamination. 7 The commenter stated that since m any other Mn results were affirmed

, EPA ’ s response to the interagency comment omitted material data and facts in EPA ’ s possession. The
commenter further contended that EPA ’ s Mn contaminat ion findings are based on a statistical tool that has not been explained. C ome stack test runs that did not suffer from Mn contamination were declared invalid

, while others suffering from alleged Mn contamination were declared valid. The commenter also sta ted they were not made aware of these Mn concerns nor given the opportunity to address them. When EPA determined that a test run suffered from Mn contamination, the commenter stated the EPA arbitrarily determined that no other HAP metal data from that test run, except Hg , was valid and usable. The commenter argued the EPA discarded valid results and thereby reduced the number of eligible data points for each HAP metal in the respective MACT floor and thereby biased the pool . The commenter asserted that the proposed PM s urrogate emission limits are arbitrary and contrary to law , since the EPA has the data to set total non

- Hg HAP metals emission limitation for this subcategory.

Commenter 0247 argued that the proposed limits are arbitrary and capricious

, becau se the EPA
cannot set supportable total PM surrogate emission limits where the EPA lacks the data to set total non

- Hg HAP metals emissions limits

. The commenter also challenged EPA ’ s use of Hg data from Mn contaminated test runs. The commenter stated t he d ocket contains no explanation for why Hg data were used, while all of the other HAP metals were excluded for Mn contaminated test runs

.

The commenter stated that EPA allowed the brick and structural clay products ( BSCP ) subcategory two options for the Hg l imit (i.e., micrograms per dry standard cubic meter ( μg /dscm) corrected to 7 percent oxygen or kilograms ( kg ) /mass in 79 FR 75683 (Dec. 18, 2014)(proposed to be codified as 40 CFR 63.8405, incorporating Table 1 of 40 CFR part 63, subpart JJJJJ) ), but provided only one option for the ceramic tile subcategory . The commenter argued that this disparate treatment is arbitrary and capricious. Expanding the available units of

measure , the commenter argued, creates incentive for the subcategory to attem pt to lower the HAP content of its glazes. The commenter stated that EPA must revisit and re

- sort the data

6 Docket Item No. EPA

- HQ OAR

- 2013

- 0290

- 023 7, Summary of Interagency Working Comments on Draft Language under E012866/13563, at page 177.

7 Docket Item No. EPA

- HQ OAR

- 2013

- 0290

- 0224, Test Data Used in Clay Ceramics Proposed Rule, at page 5 and Table 1 (Nov. 6, 2014)23 ranking for each HAP metal for each of the proposed alternative units of measure to assure the designation of the best performing source is accurate.

Response 3 : The compliance flexibility provided to the BSCP source category ( including non

Hg HAP metals limit, units of measure options) was solely related to Small Business Regulatory Enforcement Fairness Act ( SBREFA ) concerns, specifically reducing th e regulatory burden o f the numerous small entities in the BSCP category. It was not related to the availability or unavailability of HAP metals data in the Clay Ceramics source category. It should be noted that there are no major source small entities in t he Clay Ceramics source category. In addition, at the time of proposal, all Clay Ceramics sources were either estimated not to be impacted by the emission limits in the proposed rule, or had become synthetic area sources not subject to the major source pro posed rule. Consequently, the EPA concluded that no additional compliance flexibility was necessary or warranted for the Clay Ceramics source category. The arguments presented by the commenter do not change this conclusion

. The EPA disagrees that valid results w ere excluded. There was a testing issue with Mn contamination. Manganese 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. If Mn was determined contaminated then the total HAP metal run value w as not valid. Unlike the total HAP data, t he Hg data was valid because the Mn contamination was not inc luded in the calculation of the Hg data

.

Comment 4 : Commenter 0244 stated that units for the PM and Hg emission limitations f or sanitaryware tunnel kilns in Table 1 to the proposed rule should be per “ ton greenware fired, ” not per ton fired product. This is consistent with how process data were reported to EPA for the ICR.
Response 4 : The EPA agree s with the commenter’s request for a clarification in the units of measure for the PM and Hg emission limits and ha s revised the sanitaryware emission limits listed in Table 1 for the final rule as suggested.

Comment 5 : Commenter 0244 supported the use PM as a surrogate parameter for n on

- Hg metal HAP for sanitaryware glaze spray booths. The commenter requested that the unit of measure be clarified as “ per ton first fire glaze sprayed (dry weight basis), ” so there are no misunderstandings about the required process data. This is the same unit of measure as reported to EPA per ICR testing.

Conversely, Co mmenter 0247 stated that the proposed NESHAP should provide the opportunity for the regulated facility to choose among units of measure. The commenter noted that Equation 2 of proposed 40 C FR 63.8595(f), as reflected on Tables 1 and 6 (proposed to be codified in 40 CFR 63 subpart KKKKK, Tables 1 and 6) and all other relevant provisions of the proposed NESHAP

, express the PM surrogate emission limit for the glaze line with glaze spray operati ons

as “ PM emissions must not exceed [.X] kg/Mg ([.Y] lb/ton) of glaze sprayed. ” [79 FR 75655 (col. 1), preamble Table 10, note b, 79 FR 75658, and 79 FR 75658, note b, and preamble Table 11, 79 FR 75658 (Dec. 18, 2014)]

Commenter 0247 proposed that the em issions limit for PM surrogate emissions from a ceramic tile glaze line with glaze spray operation be expanded to allow compliance to be determined on a24 mass of HAP per ton of glazed tile production

- basis as an alternative to the units of measure proposed by EPA. The commenter noted that EPA proposed this approach for the BSCP subcategory in a PM context analogous to this one. The commenter argued that EPA must revisit and re

- sort the PM emissions data for the different units of measure to identify the best performing source. The commenter knew of no reason and nothing in the EPA docket that suggests why EPA could not or should not extend this flexibility to ceramic tile glaze lines. The commenter contended that a failure to do so would be arbitrary and capr icious.

Response 5 : The EPA appreciate s C ommenter 0244’s support for the PM surrogate for sanitaryware glaze spray booths. The EPA agree s with the commenter ’s request for a clarif ication in the unit s of measure for sanitaryware glaze spray booths and ha s revised Tables 1 and 6 as suggested.

The EPA does not agree with C ommenter 0247 ’s request for an equivalent limit for ceramic tile glaze lines in units of mass of HAP per ton of glazed tile production. Different glazes contain different types and amounts of HAP metals, so a single emission limit would not be representative of all the possible glazes that could be used in the process, and requiring sources to meet a different limit depending on the type of glaze used would be extremely burdensome to the ind ustry. For this reason, the EPA is not adding the requested equivalent limit for ceramic tile glaze lines to the final rule.

6.2 Type of Standard

Comment 1: Three commenters (0244, 0246, and 0247) proposed a work practice standard in lieu of an emission li mitation for D/F

. Commenters 0246 and 0247 argued there is no test method that will produce valid measurements of D/F emissions from the ceramic tile sector

. C ommenters 0246 and 0247 recommended the EPA adopt work practice standards if they regulate D/F emissions from ceramic tile kilns and tile dryers. The commenter suggested operators be required to fire their ware above 450 degrees C and operate tile dryers below 200 degrees C. They noted that EPA stated in a memorandum that

a tem perature range of 200

- 450 degrees C is “ conducive ” to the formation of D/F . [EPA Docket no. 229, at page 2 (Nov. 6, 2014), citing Characterization of the Ceramic Manufacturing Industry, RTI Memorandum Abraczinskas and Marinshaw (Dec. 3, 1999)] . While the

c ommenters disagreed that there is any temperature at which D/F is formed during tile production , they were prepared to accommodate EPA by accepting a work practice standard based on these temperature ranges

. The y noted that t emperature records recorded by existing process control equipment c ould be maintained as continuous parameter monitoring systems ( CPMS ) . The commenters supported this approach because they believe it would alleviate flaws, omissions and issues with Method 23.

Commenter 0244 opposed the proposed D/F emission limit for tunnel kilns in the sanitaryware
sector and recommended it be replaced with a work practice standard. The EPA ’ s analysis of the D/F test data for brick kilns determined that more than 55 percent of the data represented non d etects, and so qualified for a work practice standard, while only 25 percent of sanitaryware kiln data represented non detects. (See Table 4 in November 6, 2014 memo from RTI International to EPA (Telander) titled “ Determination of ‘ Non

- Detect ’ Test Data f or Clay Ceramics Proposed25 Rule. ” ) According to C ommenter 0244, brick kilns only conducted 2

- hour test runs for D/F for the ICR , while sanitaryware kilns completed 4

- hour test runs. The commenter stated it is reasonable to presume that a much higher proport ion of sanitaryware test data would be non

detect if only 2

- hour test runs were performed . The commenter asserts that the number of non

detects could have exceeded the 55 percent non

- detect threshold for allowing work practices. The commenter argued that i t is inappropriate to require different testing methodologies (2

- hour sampling runs vs. 4

- hour sampling runs) when those methodologies result in significantly different compliance requirements for the same HAP.

C ommenter 0244 stated that sanitaryware facilities have been shown to only emit HAP in area source quantities. (See Table 8 in the November 6, 2014 memo from RTI International to EPA titled “ Development of Cost and Emission Reduction Impacts for the Clay Ce ramics NESHAP. ” ) of less than 30 milligrams ( mg ) /kiln/year (80 μg /kiln/day) . W hile it ’ s possible to measure this low level of emissions, the commenters argued it is not practical to control emissions at such trace concentrations. For this reason, C ommenter 0244 asserted that a work practice standard for sanitaryware kilns similar to the work practice standard for brick kilns is justifiable for D/F

. Response 1: The EPA disagree s with Commenter 0244 ’s assertion that EPA allowed brick facilities to conduct 2

- h our test runs for D/F while requiring sanitaryware facilities to conduct 4

- hour test run s. We checked all section 114 test requests and all available electronic reporting tool ( ERT ) files and test reports of the stack tests conducted by industry in respons e to the test requests. A ll sources were required to conduct 4

- hour test runs for D/F, and all D/F test results

were documented as based on 4

- hour test runs . Based on EPA information, there i s no inconsistency between brick and sanitaryware in the length o f D/F test runs required or conducted

. Regarding the request for a D/F work practice standard, a testing program conducted under the 2010 section 114 survey detected D/F in most test runs at all of the clay ceramics facilities tested

, unlike the tests conducted at BSCP facilities . Therefore, there is no justific ation for replacing an emission limit with a work practice standard. The commenters’ request for a work practice standard is denied.

Comment 2: While Commenter 0244 supported the health

- based emi ssion limits for HF and HCl in the proposed rule, the commenter questioned why similar limits were not evaluated for the other HAP ( e.g., Hg and D/F ). Since a cid gases represent 99.3 percent of all HAP emitted from tunnel kilns per Section II.D of the prea mble and tunnel kilns emit only trace quantities of dioxin/furan and Hg, C ommenter 0244 asserted that health

- based limitations, rather than emission floors, may be also appropriate for tunnel kilns , especially since EPA has already documented that sanitary ware facilities emit only area source quantities of HAP.
Response 2: The EPA do es not agree with the commenter’s request for health

- based emission limits for D/F and Hg. Health

- based emission limits can only be established for threshold pollutants. Known, probable and possible carcinogens cannot be categorized as threshold pollutants. D/F is a probable human carcinogen, and some Hg compounds (e.g., methylmercury) are considered possible human carcinogens. Therefore, health

- based limits cannot be established for D/F and Hg.26 Comment 3: Commenter 0244 opposed the emission limitation for Hg and requested it be replaced with a work practice standard, similar to the dioxin/furan work practice standard proposed for brick kilns in the proposed Brick MACT rule (Subp art JJJJJ). Tunnel kilns have been shown to only emit HAP in area source quantities. (See Table 8 in the November 6, 2014 memo from RTI International to EPA titled “ Development of Cost and Emission Reduction Impacts for the Clay Ceramics NESHAP. ” ) Th is mem o randum shows Hg is emitted at a rate of less than 3 pounds ( lb ) /kiln/year (less than 3.5 grams/kiln/day), and while it i s possible to measure this low level of emissions, it i s not practical to control emissions at such trace concentrations. The commenter asserted that a work practice standard similar to the one proposed for dioxin/furan for brick kilns is justifiable for sanitaryware kilns. This work practice could also includ e a requirement for inside or covered storage of raw materials at each sanitaryware plant to prevent additional Hg contamination from atmospheric fallout.

According to the commenter, sanitaryware plants do not use any Hg

- containing additives and that w hile it may be possible that Hg is a trace contaminant in the raw materials, the Hg more likely comes from expos ure of raw materials to atmospheric Hg fallout from mining and processing activities. Atmospheric fallout of Hg is a confirmed environmental process (i.e., size

related fish consumption advisories for lakes all over the U.S. due to Hg levels in certain species caused by atmospheric fallout). The process of mining clays and raw materials, and the outside storage and processing, exposes the raw material s to atmospheric fallout of Hg, which is likely the single biggest factor in a raw material ’ s Hg content. All raw materials are stored indoors or in closed vessels once received at a sanitaryware plant, and there is no opportunity for additional Hg contami nation from atmospheric fallout. Sanitaryware facilities have no control over how raw materials are mined, processed, and stored by suppliers, and they should not be held accountable, through Hg emission limitations, for such potential contamination issues . The commenter stated that indoor storage of raw materials at sanitaryware facilities is a feasible work practice standard to limit Hg emissions from first

- fire tunnel kilns and should be included in this rule in lieu of Hg emission limitations.

Response 3 : The EPA do es not agree with C ommenter 0244 ’s request for work practice standards for Hg for sanitaryware tunnel kilns. Under CAA section 112(h), the EPA may set work practice standards in place of an emissions standard where it is not techn ologi cally or economically feasible to prescribe or enforce an emission standard. In this case, to support their contention that work practices are appropriate for Hg, the commenter needs to demonstrate that it is technically and economically infeasible to measure Hg f rom sanitaryware tunnel kilns. Based on available performance test results for sanitaryware tunnel kilns, w ork practice standards are not appropriate for Hg due to the levels of Hg found in the performance tests. There was only one facility that had non

- de tect levels from the laborat ory. However, those detection limits were higher than a test that had detectable values. Consequently, it is techn olog ically feasible to measure Hg from sanitaryware tunnel kilns. Based on the costs estimated for Method 29 testi ng of sanitaryware tunnel kilns, i t is also economically feasibl e to measure Hg from sanitaryware tunnel kilns. Therefore, there is no justification under section 112(h) to establish work practice standards in place of emission limits.

Comment 4: Commenter 0244 supported the option to allow emissions averaging across existing tunnel kilns and glaze spray booths for all HAP with applicable emission limits. While most of the criteria EPA cited for this alternative seemed reasonable, the commenter st ated that27 the requirement to develop an emissions averaging plan and submit it for approval by the regulatory authority was unnecessary. Averaging across similar sources is not a complicated endeavor, and asking a regulatory authority to review and approve such a plan would put this alternative out of reach for the facility if the approving authority does not act on the submittal in a timely manner. The regulated entity would have no means by which to prompt a response from the authority on this matter.

The commenter also did not support the use of a 10 percent discount factor for averaging. There
are many NESHAP in which EPA allows averaging across process lines, such as the Reinforced Plastics Composites NESHAP, which do not include any kind of safety or d iscount factor, and the commenter argued that no such factor is needed for this proposed rule. The commenter asserted that there are safety factors already incorporated into the rulemaking and standard setting process and argued that the proposed 10 percen t factor offers no practical additional environmental protection and should be excluded, particularly since sanitaryware facilities emit only area source quantities of HAP.

Response 4: The EPA does not agree with Commenter 0244’s request for emissions aver aging across tunnel kilns and glaze spray booths for their source category. The emissions averaging option discussed at proposal was meant only for the BSCP source category, as a n alternate option for addressing SBREFA concerns, specifically reducing the r egulatory burden of the numerous small entities in the BSCP category. It was never meant to be considered for the Clay Ceramics source category , which has no major source small entities. In addition, at the time of proposal, all Clay Ceramics sources were either estimated not to be impacted by the emission limits in the proposed rule, or had become synthetic area sources not subject to the major source proposed rule. Consequently, the EPA concluded that no additional compliance options (such as emissions

av eraging) were necessary or warranted for the Clay Ceramics source category. The arguments presented by the commenter do not change this conclusion

.28 7.0 MACT Floors
7.1 Determining Sources in Floor Pool
The public comments on determining sources in the M ACT floor pool can be found in section VI.B of the preamble to the Clay Ceramics final rule.

7.2 UPL

Comment 1: Commenter 0248 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 at 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 0248 stated the CAA section 112(d)(3) unambiguously requires floors to reflect the “averag e” 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 perf orming 12 percent of the existing sources.” See Webster’s Seventh 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 0248 stated in th e 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 according to the EPA, “Congress spoke with clarity in [section 112(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 0248 stated the EPA has consistently reaffirmed 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 pro cessing); 64 FR 2611, 2612 (Jan. 15, 1999) (natural gas transmission & storage); 61 FR 48208, 48210 (Sept. 12, 1996) (polymers & resins).

Commenter 0248 stated that CAA section 112(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. at29 877

- 79, 880

- 81; Cement Kiln Recycling Coalition v. EPA , 255 F.3d 855, 861 (D.C. Cir. 2001). The commenter stated speaking consistently in the past tens e, 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 0248 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 substantial evidence

- not mere assertions’ ....” Ne. Md. Waste Disposal Auth. v. EPA , 358 F.3d 936, 954 (D.C. Cir. 2004) (quoting Cement Kiln , 255 F.3d at 866 and Sierra Club v. EPA , 167 F.3d 658, 662 (D.C. Cir. 1999)).

Commenter 0248 stated although CAA section 112(d)(3) unambiguously requires floors to reflect the “average” emission level actually “achieved” by the best performing 12 percent of units, the EPA set floors at the upper prediction limit for the sources it claimed wer e 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 th e 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 best performing unit or units. The court did not state that the

“ average emissions limitation ach ieved 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
sta ndards. 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 Limi t for Calculating MACT Floors ” memo (EPA

- HQ

- O AR

- 2013

- 0290

- 0 217 ) found in the docket for this rule, for the EPA ’ s justification of the UPL approach.

Comment 2: Commenter 0248 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 other 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 Memo

- Brick at 3 ; MACT Floor Memo

- Clay Ceramics at 3.

Commenter 0248 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 member 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 emission level is n ot 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 estimate30 of the emission limitation “achieved by the average source.” UPL Memo at 10. The commenter stated the EPA does not adequately explain how the UPL is an “average.”

Commenter 0248 stated given its ordinary meaning and the meaning the EPA itself has adopted through notice

- and

- comment rulemaking, “the word ‘average’ in [section 112(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 percent to “fall bel ow” 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, an “upper bound” on what any of those sources might emit in a future test. MACT Floor Memo

- Brick at 3; MACT F loor 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 with in 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 emissio ns 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 emissions 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 analy ses 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 brick and clay ceramics manufactures

.

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

- HQ

- OAR

- 2013

- 0290

- 0 217 ) ( “ UPL memorandum ” ), in “ the context of development of MACT floors, the UPL is a value, calculated from a dataset, which identifies th e 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 predicted to be below during 99 out of 100 performance tests, including emissions tests conducted in th e 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 e xpected 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 (in the case of MACT standards, the31 dataset representing the performance of the best performers as spec ified 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 0248 stated the interpretation of the term “average” that the EPA advanced in this rulemaking 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 relevant sources’ emissions. Id . at 3. Yet the EPA also implied that the upper predic tion 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 source.” 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 stated 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 0248 stated the interpretation of the term “average” that 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 reaffirm ed many times. 59 FR 29199. The commenter stated although 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 pr ecisely the function of the UPL. The commenter stated 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 averag e emissions over time, based on both the calculated 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 upper 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, bu t is also an indication of the range of current average emissions performance of those units.

Comment 4: Commenter 0248 stated the authorities on which the EPA seeks to rest its claim that the upper prediction is an average confirm that the upper predicti on 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.h tml); Gibbons & Coleman, Statistical Methods for 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 & Ne ubauer at 1. Likewise, Gibbons and Coleman expressly note the32 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 “wide r” 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 0248 stated the EPA claimed th at 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 commenter stated the mere fact that the first el ement of the equation is an average does not demonstrate that the final product of the equation is the average over time. The EPA provided no basis on which it could reasonably conclude that just because its upper prediction equation starts with an average and then adds a number to “address variability,” this equation yields the average over time.

Commenter 0248 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 each 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 114 4.

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 co urt 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 0248 stated the EPA claimed that an emissions test dataset from another rulemaking demonstrates that the UPL for that dataset “represents t he 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 average above the 99 percent UPL,” and only the worst per forming 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 UPL 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 prediction, id ., is irrelevant. The commenter stated accordin g 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 achieved by the “average source” among the best performers, i d . 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.33 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 tha n 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 equ ation being added to the average component of the UPL equation. The variance component of the UPL equation is dependent on the variability of the test runs from the entire MACT floor pool. In the Case B example provided by the EPA in the UPL Memo

, the vari ance 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 no t always result in “all the best performers falling below the calculated UPL.” For MACT floor pools that contain sources with little variability between all the runs resulting in a low variability component, the likelihood of all the sources in the pool be ing able to meet the calculated UPL decreases. For MACT floor pools that contain sources with a great amount of variability between all the 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 0248 stated by setting floors at the upper prediction limit, the EPA also contravenes CAA section 112(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 “achieved,” not what EPA predicts they will achieve in the future. See Sierra Club , 479 F.3d at 880

- 81. The commenter stated th e 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 not 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 112(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 d oes 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 0248 stated Congress enacted section 112(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 0248 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.3d34 at 1131. The commenter stated nowhere in the record has the EPA demonstrated that its UPL is an accurate estimate of the “average” emis sion level that the relevant best sources have actually “achieved,” or that it reflects what the best controlled source “achieved in practice.” The commenter stated the UPL is neither the average emission level achieved by the best performing
sources nor t he emission level achieved by an average source; rather, it is a level the EPA expects sources in the top 12 percent

-- including the worst

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

Commenter 0248 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 achieved in the past

-- which it 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 operators take to control their emissions, including fuels they choose to burn, controls they install, and the care with wh ich 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 thes e factors as inherent variability results in floors that do not reflect the best source or sources’ actual performance. The commenter stated 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 reflect emission levels “a ctually a chieved. ” The commenter misunderstands the purpose of the UPL calculation. It is not intende d to only predict the best performing sources’ future performance, although it can be used to do that. Rather, for the purpose of setting MACT standards, it is used to estimate the best performing sources’ current emissions over time, rather than during th e very short

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

- term stack test. This is a reasonable in terpretation 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 because it incorporates the average performance of the best performing sources and the variability of the performance durin g testing conditions. The commenter is incorrect that the UPL calculation results in an emissions level that the worst source in the top 12 percent of sources will fall below. As explained in the “Use of the Upper Prediction Limit for Calculating MACT Floo rs” memo (EPA

- HQ

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- 029 0

- 0 217 ), the UPL calculation begins with the
average emissions level of the best performing sources, and then applies a second step in order to account for the variability in emissions performance of those sources. For the deve lopment of the Hg floor, the variability of the raw material was also taken into account. The UPL represents the value which one can expect the mean of a specified number of future observations to fall below for a specified level of confidence based upon t he results of an independent sample from35 the same population

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

- HQ

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- 029 0

- 0 217 ) 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 the 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 under which it was tested, is a necessary component of the UPL calculations; otherwise, the randomness to which the comm enter refers could creep in. As the emission limits are established on a certain set of practices and operations associated with a successful performance test of the best

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

Comment 7: Commenter 0248 stated the UPL is a particularly inaccurate representation of what the best source or sources “actually achieved” where th e emissions dataset is small; as the D.C. Circuit has recognized, the results generated by the EPA’s upper prediction approach depend heavily “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 of the UPL” for small datasets introduces “uncertainty” in the calculation of MACT standards. EPA, Approach for Apply ing the Upper Prediction Limit to Limited Datasets at 2 (Sept. 17, 2014), Docket Item No. EPA

- HQ

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- 0291

- 0127 (hereinafter “Limited Datasets Memo

- Brick”). The commenter stated the “number of values in a particular dataset[] is an important componen t 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 uncertainty and variability for a certain confidence level, and “is highly variable at the smallest sample sizes” and “can ha ve 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 lar ger (all other variables being constant). Id . at 4. The sample size is a “key component” in the calculation of two other variables in the EPA’s UPL equation: the mean and variance; “larger sample sizes provide better estimates of the population mean and va riance.” 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 0248 stated in light of the significant and pervasive uncertai nty that small sample sizes introduce into the UPL calculation, the UPL cannot represent the performance that the best sources “actually achieved,” as the Act requires, where sample sizes are small; and the EPA is frequently faced with the task of establis hing floors where it has limited data. The commenter stated for example, in these rules alone, the EPA identified 20 floors for which the EPA had fewer than 7 data points. See id . at 8; EPA, Approach for Applying the Upper Prediction Limit to Limited Datas ets at 8 (Sept. 17, 2014), Docket Item No. EPA

- HQ

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- 0290

- 0218 (hereinafter “Limited Datasets Memo

- Clay Ceramics”). The commenter stated the serious shortcomings in the UPL for small datasets alone highlights the need to abandon the UPL approach.36 C ommenter 0248 stated the EPA recognizes that the UPL generates higher and potentially inaccurate and unrepresentative floors where the sample 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 associated with a limited dataset does not cause the calculated emission limit to be so high” as to be illegal. Limite d 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 causes the UPL to be unacceptably “high,” except that the EPA will use its “experience” and “technical expertise” in i ts evaluation. Id . at 6

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

Commenter 0248 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 a ccurate limits. The commenter stated the EPA is asking that it be trusted to take a second look at an admittedly flawed formula and make sure it is “reasonable.” Id . at 7 (“we ... would ensure that the emission limit is reasonable”); id . at 6 (“The evaluat ion will include one or more of the following ...: confirming that the data distribution was selected correctly” and “ensuring that we use the 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 standa rd

- setting method being applied is undisputedly defective.

Commenter 0248 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 b ased on small datasets, the EPA concludes without much reasoning that no adjustments were warranted.

Commenter 0248 stated also, the EPA fails to rationally explain why sample sizes smaller than 7 require further evaluation, but slightly larger sample size s 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 ignored; it is irrelevant that the test data itself may have some uncertainty, as the EPA points out: uncertainty elsewhere i n the standard

- setting process does not justify use of a method to account for variability that adds even more uncertainty to the outcome. The commenter stated if anything, additional uncertainty caused by the EPA’s proposal to use a UPL is less justifiabl e 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 for limited datasets. A limited datase t does not automatically mean that the calculated UPL is flawed and should not be used; however, given the potential impact of uncertainty due solely to the number of samples, it is appropriate for the EPA to assess all factors used in the UPL calculations when determining an emissions limit, so that the emissions limit reflects the average performance of the units upon37 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 size dependent component of the UPL equation, the t

- statistic

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

- statistic for sample siz es 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 off and have a lesser contribution to the UPL equation. As such, the limited dataset cutoff was determined t o be below 7 samples.

Please see the “ Approach for Applying the Upper Prediction Limit to Limited Datasets ” memo (EPA

- HQ

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- 029 0

- 0 218 ) for more information regarding the UPL approach for limited datasets.

Comment 8: Commenter 0248 stated the EPA’s sp ecific 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 “reasonable assuranc e 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 it s 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 arbitrary. The comm enter 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 calc ulated 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 ( see Docket Item No. EPA

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- 029 0

- 0 217 ).

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, 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 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 units. In other words, the 99 percent UPL is th e 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.38 7. 3 Emission Limit

Comm ent 1: Commenter 0247 challenged the proposed D/F emissions standards for new and existing wall tile kilns. EPA proposed D/F emissions limits for existing and new wall tile kilns of 0.16 ng/dscm and 0.160.23 ng/dscm, respectively, each corrected to 7 perce nt oxygen. 8 EPA ’ s research and calculations showed the correct emissions rate in each scenario to be 0.17 ng/dscm. 9 Table 6 correctly reflects EPA ’ s research and calculations, identifying the correct emissions rate of 0.17 ng/dscm. 10 Commenter 0247 stated that EPA must correct the D/F standard for new and existing kilns to 0.17 ng/dscm in Table 1. The commenter argued that a failure to do so would be arbitrary and capricious.
Response 1: The EPA agrees with the commenter that the D/F emission limits for wall tile roller kilns in Table 1 t o subpart KKKKK were incorrect. In response to another comment from this and other commenters, we have changed the format of the D/F emission limits in Table 1 from nanograms per dry standard cubic met er ( ng/dscm ) to nanograms per megagram ( ng/Mg ) of fired product.

Comment 2: Commenter 0247 challenged the proposed Hg standards for new and existing wall tile kilns. EPA inaccurately proposed Hg emissions limits for existing and new wall tile kilns of 6.7 E

- 05 kg/Mg (1.3 E

- 04 lb/ton) and 1.9 E

- 05 kg/Mg (3.1 E

- 06 lb/ton) of fired product. 11 These values are inconsistent with the 2.0 E

- 4 kg/Mg proposed emission limit for new and existing wall tile kilns developed by EPA and presented in the EPA docket. 12 Table 6 correctly reflects the emissions limitations in the docket for existing and new wall tile kilns. 13 Commenter 0247 stated that Table 1 must be corrected to reflect the emission standards developed by EPA and provided in the docket. The commenter argued tha t a failure to do so would be arbitrary and capricious.
Response 2: The EPA agrees with the commenter that the Hg emission limits for wall tile roller kilns in Table 1 to subpart KKKKK were incorrect. Rounding up to the next decimal results in a limit of 2 .1E

- 04 lb/ton of fired product for wall tile roller kilns.

In our review of Table 1 values, we discovered that Table 1 also contains errors for wall tile PM emission limits, although Table 6 ha d the correct values . Under I tem 3.a , the PM emission limit for existing wall tile roller kilns was 0.099 kg/Mg (0.20 lb/ton)

, and it should have be en 0.10 kg/Mg (0.20 lb/ton) . Under I tem 13.a , the PM emission limit for new wall tile roller kilns was 0.15 kg/Mg (0.27 lb/ton)

, and it should have be en 0.10 kg/Mg (0.20 lb/ton)

. Since proposal, we have examined the PM test data more closely and found that a number of the EPA Method 5 test runs had probe or filter temperatures outside of the range of acceptable values. EPA Method 5 specifies that the temp erature should be maintained at 248 ± 25 degrees Fahrenheit (°F) ( i.e.

, between 223 and 273 °F). Test runs with temperatures outside that range were removed from the

8 79 FR 75704 (Dec. 18, 2014)(proposed to be codified as Table 1, rows 3c. and 13c. of 40 CFR 63, subpart KKKKK)

9 Docket Item No. EPA

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- 0226, Maximum Achievable Control Technology (MACT) Floor Analysis for Clay Ceramics , at Tables 2 and 3, pages 12 and 13 (Nov. 6, 2014).

10 79 FR 75709 (Dec. 18, 2014)(proposed to be codified as Table 6 of 40 CFR 63, subpart KKKKK)

11 79 FR 75704 (Dec. 18, 2014)(proposed to be codified as Table 1, rows 3b. and 13b. of 40 CFR 63, subpart KKKKK).

12 Docket Item No. 226, at Tables 2 and 3, pages 12 and 13 (Nov. 6, 2014).

13 79 FR 75709 (Dec. 18, 2014)(proposed to be codified as Table 6 of 40 CFR 63, subpart KKKKK).39 data set , including test runs from the wall tile roller kilns . As a result, the PM MACT fl oor for wall tile roller kilns was recalculated , resulting in a revised PM limit of 0.37 lb/ton of fired product for existing and new wall tile roller kilns.

Comment 3: Commenter 0247 argued that EPA has no legal authority to promulgate a D/F standard bec ause there is no certainty TCDD of biogenic origin is a listed HAP . The commenter stated that legislative history of the CAA and EPA guidance show the TCDD listing was intended to apply to only TCDD of anthropogenic origin

. Congress stated “ [T]here are hun dreds of air toxics of concern [including] . . . and dioxin (a product of combustion whenever there is chlorine in the fuel.) ” . S. REP. I 01

- 228 at Ill. The commenter stated that the phrase “ [D]ioxin (a product of combustion ... ) ” is an unmistakable refer ence to D/F emissions of anthropogenic origin. The commenter also noted that the pipeline

- quality natural gas used exclusively by these

sources does not contain Cl 2

. The commenter stated that Congress never intended biogenic D/F , including TCDD, to be a HA P subject to NESHAP regulation. The commenter argued that D/F emissions from the ceramic tile manufacturing industry, if they exist, are biogenic, not anthropogenic, and tightly encapsulated in

a ball clay matrix. There is no evidence in the docket that establishes it is of non

- anthropogenic origin. The commenter argued the D/F emissions do not have the D/F congener profile of new D/F created as a product of combustion. When Congress intended in the CAA to regulate biogenic compounds as hazardous air poll utants, the commenter noted that Congress explicitly granted EPA the authority to do so (e.g., regulat ion the emission s of “ naturally

- occurring ” radioactive materials as a HAP, S. REP. 95

- 564 at 142 )

. According to the commenter, t he fact that Congress chos e not to refer to naturally

- occurring or biogenic D/F is a strong indication, coupled with the legislative history that Congress chose not to regulate the emission of biogenic encapsulated D/F . EPA ’ s “ Locating and Estimating Air Emissions From Sources of D ioxins and Furans ” (United States Environmental Protection Agency, Office of Air and Radiation, EPA

454/R

- 97

- 003, May 1997) makes it clear that the section 112(b) listing of TCDD is strictly limited to D/F of anthropogenic origin: “ [chlorinated dibenzo

- p

- d ioxins] and [chlorinated dibenzofurans] .... are formed as unwanted byproducts of certain chemical processes during the manufacture of chlorinated intermediation and in the combustion of chlorinated materials.. ” The commenter noted that although the EPA li sted several examples of industries that emit D/F, they did not list a ceramics manufacturing operation in this guidance document. The commenter noted that when this document was written in 1997, the discovery of biogenic dioxin in ball clay was known to E PA.

Response 3: The EPA disagrees with the commenter that EPA has no legal authority to promulgate a D/F standard because biogenic D/F is not a HAP. In the congressional statement cited by the commenter, Congress never intended to make the distinction between anthropogenic and biogenic D/F when it stated that “dioxin [is]...a product of combustion whenever there is chlorine in the fuel.” Congress was simply stating the most common mechanism by which dioxin is created. There are many mechanisms by which so me HAP are created

-- some natural ly , some artificial ly through the manufacturing process. There is no basis for concluding that Congress intended for EPA to regulate HAP created by one mechanism and not another.

Comment 4: Commenter 0247 contended that EPA ’ s proposal to regulate congeners raised constitutional concerns by creat ing new law

. The commenter noted that d ioxin is not on the CAA40 section 112(b)(l) HAP list and the EPA propos al would regulate sixteen congeners as if they were TCDD, using toxicity equ ivalency factors ( see 79 FR 75709 (Dec. 18, 2014)(proposed to be codified as Table 5 of 40 CFR 63, Subpart KKKKK). The ability to mathematically compare the toxicity of each of the sixteen congeners to one another and to TCDD is interesting and may be usef ul in other public health contexts, but it does not overcome the statutory limitation that EPA is permitted to regulate only compounds listed by Congress as HAP in CAA section 112(b)(1).

The commenter stated there are constitutional and statutory limitatio ns to EPA ’ s authority and EPA has no authority to rewrite CAA section 112(b)(1). Congress specifically provided CAA section 112(b)(2) and (3) in the event EPA thought CAA section 112(b)(1) list needed amending. EPA can petition Congress to make such change s, and Congress will decide whether or not to rewrite this part of the law. Commenter 0247 argued that EPA ’ s proposal, which attempts to bypass the law by regulating possible emissions of the 16 D/F congeners as if they are TCDD, is arbitrary and capriciou s.

Commenter 0247 also stated that EPA did not address in this rulemaking their authority to regulate emissions of these 16 congeners within the HAP category of polycyclic organic matter (POM) and therefore, the EPA is barred from doing so in response to t hese public comments. The commenter argued that none of the 16 D/F congeners meets EPA ’ s definition of POM. EPA ’ s website defines POM as “ organic structures having two or more fused aromatic rings that have a boiling point greater than or equal to 212 degr ees F (100 degrees C). ” See Polycyclic Organic Matter (POM), United States Environmental Protection Agency, www.epa.gov/ttnatw0l/hlthef/polycycl.html . EPA ’ s guidance entitled Locating and Estimating Air Emissions from Sources of Polycyclic Organic Matter (p. 3

- 1, United States Environmental Protection Agency, Office of Air Quality Planning and Standards, EPA

- 454/R

- 98

- 014, July 1998) and EPA guidance defines POM as: “ ... a broad class of com pounds which generally includes all organic structures having two or more fused aromatic rings (i.e., rings which share a common border). ” Biogenic D/F , including non

- TCDD, in ball clay does not have two or more fused aromatic rings

. T he aromatic rings are connected by oxygen atoms without a common border. Since b iogenic dioxin falls outside EPA ’ s definition of POM , the proposed D/F standard that includes these sixteen congeners is arbitrary and capricious.

Response 4: The EPA disagrees with the comment er t hat the EPA is not authorized to regulate dioxin congeners beyond 2,3,7,8

- TCDD

. While 2,3,7,8 TCDD is one of the HAP listed in section 112, all dioxin congeners are considered to be POM (which is listed in CAA section 112(b)(1)) and, as such, the EPA has t he authority to regulate these compounds under section 112. The commenter cites two references in his argument that dioxin congeners are not POM:

• Polycyclic Organic Matter (POM), United States Environmental Protection Agency, www.epa.gov/ttnatw0l/hlthef/po lycycl.html; and

• Locating and Estimating Air Emissions from Sources of Polycyclic Organic Matter (p. 3

- 1, United States Environmental Protection Agency, Office of Air Quality Planning and Standards, EPA

- 454/R

- 98

- 014, July 1998).41 The first reference states that “[e] ight major categories of compounds have been defined by the EPA to constitute the class known as POM ,” and cites the second reference

-- the Locating and Estimating ( L&E ) document for POM sources

-- for the list of categories. That list of categories (provided on p. 3

- 2 of the L&E document ) includes polyhalo compounds, and the L&E states that “some polyhalo compounds, such as polychlorinated dibenzo

- p

- dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs)

, may be considered as POM although they do n ot have two or more fused aromatic rings.” Therefore, according to the commenter’s own references, the EPA is authorized to regulate dioxin congeners beyond 2,3,7,8

- TCDD.

Further, the EPA disagrees that it was required to explain the basis for its authority to set standards for dioxin congeners in the proposed rule preamble. Such authority has already been recognized previously in many other EPA rules (e.g., Boiler MACT, Hazardous Waste Combustors , Large/Small Municipal Waste Combustors

, Commercial and Institutional Solid Waste Incinerators , HMIWI, Other Solid Waste Incinerators

, and Sewage Sludge Incinerators )

. The c ommenter has raised this issue in his comments, and the EPA has provide d the response above. This is fully consistent with the procedural provisions of CAA section 307(d).

Comment 5: Commenter 0247 argued that EPA ’s propos al regulate s Hg emissions twice: on their own and as part of PM as a surrogate for HAP metals ( 79 FR 7565 1 (col. 3)

, Dec. 18, 2014 ; proposed to be codified at 40 CFR 63.8555(a), incorporating Table 1, and 40 CFR 63.8595(f)(1)). This problem arises from EPA ’ s proposed definition of PM , which includes Hg (see 79 FR 75682 (col. 3)

, Dec. 18, 2014 ; proposed to be codified as a portion of 40 CFR 63.8665). The commenter presumed that EPA intended to regulate Hg emissions once. The
commenter stated that double regulation of a pollutant in the same NESHAP is arbitrary and capricious, and unlawful. The co mmenter asserted the EPA must re

- propose the proposed NESHAP to provide the public the opportunity to provide public comment on the option that EPA chooses to correct this double regulation.
Response 5: The EPA agrees with the commenter that Hg should not have been included in the definition of PM, because PM is being regulated as a surrogate for non

- Hg metals. We have revis ed the definition of PM for the final rule to remove mention of Hg. Re

- proposal is
unnecessary , because commenter s w ere fully able to p rovide comment on this issue. Further, t he mass of Hg compared to the mass of filterable PM is very small, so the removal of Hg from the definition of PM will make essentially no difference in the calculation of filterable PM.

7. 3 .1 Manipulation of Data fo r MACT Floor

Comment 1: Commenter 0247 challenged the proposed floor tile kiln D/F MACT floor pool and resulting proposed D/F standards. The commenter argued that EPA ’ s proposed approach to establishing MACT floor pools in circumstances where common stack emissions are involved is internally inconsistent and inconsistent with EPA NESHAP precedent. For kilns, EPA divided common stack emissions equally among all kilns exhausting to that stack and ranked each kiln ’ s

“ emissions ” separately for MACT floor pool p urposes. By contrast, for glaze lines, EPA included the common stack emission factor as a single data point for MACT floor pool purposes, irrespective of the number of glaze lines exhausting to that common stack. The commenter contended that EPA ’ s treatmen t of the glaze line s is consistent with past EPA precedent; while its treatment of the kiln s is not

. EPA offered no explanation for this inconsistent treatment of42 kilns. The commenter stated that there is no distinction to be made and thus the treatment of the kilns is arbitrary and capricious, and must be corrected.

The commenter stated EPA’s approach to kilns skews the MACT floor pool and the proposed emissions standard for each HAP in two ways. First, for every kiln associated with a common stack include d in a MACT floor pool after the first one confirmed by EPA precedent, at least one kiln that would otherwise have ranked high enough to be included in that pool has been excluded. As a result, t he proposed kiln MACT floor pools lack the top five performin g sources, which violat es CAA section 112(d)(3)(B). In addition, by including the same emission result more than once in a MACT floor, the variability within a MACT floor pool is artificially and unlawfully narrowed. This distorts the statistical variability adjustment of the MACT floor data set required by the NACWA Court that a different statistical template (skewed, lognormal or normal) driven by the narrowed data set may add to the inaccurate calculation of the relevant emission standard.

Specifically, the commenter stated that EPA used the Oklahoma kiln ’ s common stack test result three times in the proposed floor tile kiln D/F MACT floor. Kilns 60, 61 and 62 are ranked second, third and fourth, respectively, in this pool. Commenter 0247 challenged the inclusion of three separat e kilns in this MACT floor when in fact there was only one test result from the common stack. F or the se reasons, the commenter proposed the more logically correct and historically consistent method of counting the Oklahoma test as a single data point. When this is done, kiln 77, which was the sixth

- ranked in this floor development, would be added to this MACT floor pool. There would be four values in this revised MACT floor pool.

Commenter 0247 argued that EPA ’ s proposed UPL

- based D/F standard of 4.6 ng/dsc m is arbitrary and capricious because it is oxygen

- corrected and based on the inclusion of kilns 60, 61 and 62 in the D/F MACT floor pool. Using EPA ’ s data , the commenter calculated the UPL

based D/F standard to be 6.41 ng/dscm, when the proper four kiln M ACT floor pool is used.

The removal of 7 percent oxygen correction results in a calculated equivalent to the 4.6 ng/dscm UPL

- based D/F standard of 0.68 ng/dscm at standard conditions of temperature and pressure. The commenter stated that the oxygen correct ion is in appropriate and the 0.68 ng/dscm limit is arbitrary and capricious because it is based on inclusion of kilns 60, 61 and 62 in the D/F MACT floor pool. T he commenter proposed a UPL

- based D/F standard of 2.68 ng/dscm at standard conditions of temper ature and pressure, exclusive of oxygen correction to 7 percent for the four kiln pool.

Response 1: For categories where a significant number of units are ducted to one outlet stack, the EPA designate d the outlet stack as the “source” instead of each indiv idual unit. The EPA used this methodology for tile glazing and the wall tile roller kiln categories. In the tile glazing category, several facilities have multiple glazing lines ducting to one stack. In the wall tile roller kiln category, there is one faci lity with 12 uncontrolled kilns going to one stack. For all other tile and sanitaryware categories where a less significant number of units du cted to the same outlet source, the EPA treated the units as distinct individual sources to be consistent with the methodology used in BSCP.43 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 compliance 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 t he unit ha ve 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 ha ve significant variability, then removing the duplicate k iln from the MACT floor pool will usually decrease the overall variance and decrease the UPL val ue.

In general

, treating units as distinct individual sources vs. a single source does not result in significant differences in the final UPL.

I t should be note d that, i n response to a public comment requesting different units of measurement for the D/F MACT floor , the EPA is now regulating D/F in units of ng/kg instead of ng/dscm at 7 percent O 2

.

Comment 2: Commenters 0246 and 0247 challenged the use of oxygen correction in the development of the proposed D/F standard (see 79 FR 75704

, Dec. 18, 2004 ; to be codified as Tables 1, 6 and 7)

. The commenters proposed instead that EPA use the raw D/F data without oxygen correction in developing the MACT D/F floor and s etting D/F standards, arguing that EPA ’ s selection of an oxygen

- corrected standard was arbitrary and capricious.

Commenter s acknowledged that EPA had used emissions results “ corrected to 7% oxygen ” to set D/F emission standards in other NESHAP , but stated that the nature of the processes in the ceramic tile subcategory is such that they must operate at near

- ambient air conditions. They argue t his distinction is critical because the oxygen correction equation creates distortion in the reported r esults at the near

- ambient oxygen concentration conditions found in the ceramic tile industry

. The commenter stated that oxygen correction of raw data to 7 percent obscures identification of the best performing sources. The reported floor tile kiln exhaust gas oxygen concentrations, for example, range from 16.13 percent to 19.23 percent

. A ssuming these are the only two floor tile kilns in this subcategory and that they each emit D/F at the same concentration , then t he oxygen correction s would be 2.914 and 8 .323 , respectively

. In this example, C ommenter 0247 noted that the kiln with the 19.23 percent oxygen concentration reports 7 percent oxygen

- corrected results that are higher by a factor of 8.323/2.914 (roughly three times higher) than those for the kiln w ith the 16.13 percent oxygen concentration. With the

same D/F concentration, the kiln with the 16.13 percent oxygen concentration would be deemed the best performing , when this kiln could actually emit more D/F on a concentration basis.

Commenter 0247 also noted EPA ’ s Method 3A and the oxygen measurement equipment do not yield precise oxygen concentration s

. A t near

- ambient oxygen concentrations, even a slight variation in oxygen concentration measurement has a material impact on oxygen

- corrected results

. The commenters argued that t hose impacts are not considered when EPA takes statistical variability of the data in the MACT floor pool into account. The assumption underlying that44 protocol is that the D/F MACT floor data pool are precise, when in fact the y too are subject to statistical variability associated with, among other things, the oxygen concentration measurement equipment. The commenter argued that the proposed D/F standard failed to satisfy the statistical variability requirements stated by the N ACWA Court and is therefore arbitrary and capricious.

C ommenter 0247 acknowledged that oxygen correction creates a disincentive for operators to lower their emission concentration by introduc ing dilution air. However, the commenter stated that this approac h is not possible in the ceramic tile manufacturing industry because the a ir flow is tightly controlled to assure a quality finished product. There is no incentive to introduce dilution air that could cause product quality problems.

C ommenters 0246 and 024 7 recommended that if D/F standards are included in the final rule, they should be based directly on raw D/F emissions data. If EPA decides to use data corrected for oxygen, then c ommenters 0246 and 0247 suggested the D/F emission limitations reflect
oxyge n correction to the maximum reported oxygen concentration for each source type (i.e., 19.23 percent for kilns ) . Commenter 0247 stated that any oxygen concentration over the maximum measured during ICR stack testing of that source type could be defined as “ excess. ”

Response 2: In response to a public comment requesting different units of measurement for the D/F MACT floor, the EPA is now regulating D/F in units of ng/kg instead of ng/dscm at 7 percent O 2

. Therefore, the commenter’s argument is no longer applicable.

Comment 3: Commenter 0247 challenged the proposed floor tile kiln Hg MACT floor pool and resulting proposed Hg standard. EPA has used the same Oklahoma kilns stack test result twice in the proposed floor tile kiln Hg MACT floor pool. EPA ranke d kilns 60, 61 and 62 fourth, fifth, and sixth, respectively, in this MACT floor. Commenter 0247 challenged the separate inclusion of each of these three kilns in this MACT floor, and the use of the common stack emission factor twice in the MACT floor pool . The commenter proposed that the MACT floor include only the single emissions factor from the common stack serving kilns 60, 61 and 62. Kiln 41, which was the seventh

- ranked in this floor development process, would become a MACT floor pool participant wit h this correction.

In addition, the commenter stated that the emission result for the common stack within this MACT floor pool must be corrected. There is a transcription error in the May 13

- 14, 2010 impinger lab data for run 2, which appears in EPA docket run

- by

- run spreadsheet cell AL6. A value of 41.1 was entered, but the laboratory reported 51.1. The commenter indicated this error must be corrected and the MACT floor calculations redone.

Commenter 0247 also stated that the production tonnage throughput rate for kiln 77 from the March 4

- 5, 2010 stack test in cells P17, P18, and P19 of EPA ’ s docket run

- by

- run spreadsheet does not reflect production tonnage rate reported in the stack testing report. The kiln run rate in the spreadsheet erroneously correspon ds to confidentially

- submitted run rate data for a press dryer. Inclusion of kiln 77 means there will still be five values in this revised MACT floor pool.

Commenter 0247 calculated the revised Hg UPL

- based standard for this revised five

- kiln pool to be 3. 72 E

- 04 lb./ton. The commenter argued that EPA ’ s UPL of 1.3 E

- 4 is erroneous, arbitrary and capricious.45 Response 3: The EPA is maintain ing its methodology for treating multiple units ducted to one outlet for the floor tile roller kiln subcategory. The unit s will be treated as individual sources. The EPA has revised the production rate for kiln 77 and recalculated the emissions for that unit. The EPA has reranked the units and recalculated the UPLs accordingly. Please see the MACT floor memo for changes to t he calculated UPL and final MACT floors.

Comment 4: Commenter 0244 stated that the analyses presented in Tables A

- 12 through A

- 14 of the November 6, 2014 memo from RTI International to EPA (Telander) titled “ MACT Floor Analysis for Clay Ceramics, ” show ki lns 19 and 20 as separate sources with the exact same average emission rate and variance. As these two kilns exhaust through the same stack, they were tested simultaneously. The commenter asked EPA whether they should be treated as a single kiln since a si ngle exhaust was tested. The commenter asked whether treating them as two distinct kilns, with identical emission rates and variability, minimizes the variability calculated via the UPL approach, resulting in a lower emission limit for sanitaryware kilns t han would be the case otherwise.
Response 4: The sanitaryware tunnel kilns were treated as two distinct kilns vs. a single kiln to be consistent with the MACT floor methodology used in both the BSCP and f loor t ile categories

. The same methodology for each sanitaryware tunnel kiln pollutant MACT floor was used, treating units going to the same stack as distinct kilns.

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, v ariability of the data in the MACT floor pool,
t

- statistic, and “ m ” future compliance 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 ha ve 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 ha ve significant variability, then removing the duplicate kiln from the MACT floor pool will usually decrease the overall variance and decrease the UPL value.

For sanitaryware kilns 19 and 20, treating them as two distinct kilns vs. a single kiln does not result in significant differences in the final UPL for Hg

, PM , or TEQ

.

Comment 5: Commenters 0246 and 0247 challenged the proposed MACT PM surrogate floor pool and resulting PM surrogate standard for floor tile kilns

. The commenters stated that EP A ’ s UPL

- based existing kiln emission standard of 0.18 lb/ton and new source emission standard of 0.027 lb/ton are arbitrary and capricious.

Specifically, c ommenters challenged EPA ’ s inclusion of PM data from kilns lacking air pollution control equipment. T he commenters stated that controlled versus uncontrolled are two different scenarios and noted that the one controlled kiln in this MACT floor pool ( kiln 41 ) has the highest reported PM emissions of the five kilns in the MACT pool. Kilns 77, 84, 36, and 76 , which are all uncontrolled, are ranked 1

- 4. While o ne would expect operations with air pollution control equipment have lower emissions than their uncontrolled counterparts

, air pollution control46 systems , such as DIFF system s , contribute to the higher me asured PM emissions. According to the commenters, EPA’s documentation for this industry confirms PM emissions from sources controlled by an air pollution control device are greater than uncontrolled sources.

If all major sources operate with controls, the commenters asserted that imposing an emission limitation on existing floor tile kilns that is strongly influenced by uncontrolled sources is arbitrary. Further, the commenters argued, imposing an emission limitation on new floor tile kilns at major sources based on an uncontrolled source (kiln 77) is arbitrary and capricious. The commenters asserted that f loor tile kilns with emission controls would be penalized because they are controlled.

To correct this situation, c ommenters 0246 and 0247 proposed an exi sting floor tile PM surrogate pool consisting of the best performing PM controlled sources (i.e., kilns 41, the single emission factor from the tests of the common stack (wet scrubber 1) serving kilns 59 and 60, and the single emission factor from the test s of the common stack (wet scrubber 2) serving kilns 60, 61 and 62 ) . The corrected UPL

- based emission standard for this three

- source existing source pool is 0.69 lb/ton.

The commenters also opposed the proposed standard for new sources because the standar d was based on data from an uncontrolled kiln ( i.e., kiln 77). Since the kilns in this MACT pool have already installed controls and will not be able to cease operation to meet the proposed standard, the commenters stated the correct UPL

- based new kiln emi ssion standard should be 0.447 lb/ton

, based on data from kiln 41

.

T he commenters also challenged EPA ’ s inclusion of the 2003 PM data for kiln 76 in th e MACT floor pool. The kiln throughput during that testing event was only 79 percent of design capacity, which is well below the 90 percent required for use in state permit compliance contexts. The commenters argued PM emissions data for this kiln should no t be included because : (1) operations at reduced throughput are not representative of the normal operation of a kiln ; (2) HAP metals were not tested ; and (3) EPA Method 5 was used instead of Method 29 specified by the ICR

. The commenters contended that the reported results in the 2003 test of kiln 76 do not speciate metals and thus, provide no correlation between metals and PM emissions.

In addition, the commenters identified a transcription error in the production tonnage for the kiln 77

, March 4

- 5, 2010 s tack test. They stated the error in the throughput affects the PM emissions pool for cells P65, P66 and P67 in the EPA ’ s kiln PM run

- by

- run spreadsheet. The commenters stated that EPA must use the production rate for kiln 77 d uring the stack test that was reported in the declassified confidential business information ( CBI ) letter dated August 6, 2010 (See EPA

HQ

- OAR

- 2013

- 0290

- 0090 )

. C ommenters 0246 and 0247 calculated the revised existing kiln PM UPL

- based emission standard based on the five

- source pool and corrected throughput for kiln 77 to be 0.23 lb/ton.

Response 5: The EPA cannot exclude kilns lacking air pollution control equipment from the MACT floor calculation

. Cement Kiln Recycling Coal v. EPA , 255 F.3d 855, 866 (D.C. Cir. 2001); Sierra Club v. EP A , 479 F.3d 875, 882

- 83 (D.C. Cir. 2007). T he EPA is continuing to47 rank all the sources for which they have data for the floor tile roller kiln category. The EPA has revised the production rate for kiln 77 and recalculated the emissions for that unit.

Comment 6 : Commenter 0248 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 including such data in its floor analysis, EPA inflated the proposed l imits 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; startup and shutdown emissions do not reflect the sources’ actual emi ssions during other operations.
Response 6 : 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

.
7. 3 .2 3xRDL

Comment 1: Commenter 0247 argued that EPA ’ s proposed Hg standards for existing and new floor tile glaze lines with glaze spray operations, new floor tile spray dryers, tile dryers and wall tile spray dryers fail to satisfy statistical confidence requirements. Commenter 0247 accepted EPA ’ s approach of comparing the appropriate 3xRDL value to the calculated UPL value for each pollutant and subcategory and selecting the larger value as the MACT floor emission limit. However, the commenter challenged the three

- times multiplier. Absent statistical conditions not present here, NESHAP UPL

- based emission standards are required by EPA precedent to be set at the 99 percent statistical confidence level (see Approach for Apply ing Upper Prediction Limit to Limited Datasets, EPA docket EPA

- HQ

- OAR

- 2010

- 0895, at 2

- 5 (Sept. 3, 2014) ). The statistical confidence level for 3xRDL is only 85

- 90 percent according to EPA: “ Relative pollutant measurement imprecision decreases to a consiste nt 10 to 15 percent for values measured at a level about three times the method detection limit (ASME, 2001). ” [ Id .] Elsewhere in this reference source, EPA suggests that the imprecision associated with the RDL is 10

- 20 percent. [ Id . at page 11] Therefore, 3xRDL

- based emission limits are at least 10 and as much as 15

- 20 times statistically less achievable than UPL

- based emissions limits. The commenter argued that the choice of the three

- times multiplier fails to correctly account for statistical variability as required by National Association of Clean Water Agencies, et al. v. United States Environmental Protection Agency , 734 F.3d 1115 (D.C. Cir. 2013) ( NACWA ), and is arbitrary.

Commenter 0247 stated that EPA must correct this inconsistency by increasing th e RDL multiplier so it is at the 99 percent statistical confidence level. An 8x multiplier may be supportable in its statistical comparability to the UPL. With that adjustment, the commenter would support EPA ’ s approach to setting the proposed Hg emission limit for each of the referenced units at the greater of the UPL and the revised, higher multiplier of the RDL.

Response 1: The EPA disagrees with the commenter, as he appears to mix two separate issues

– the confidence level necessary to determi ne presence or absence of a pollutant and the precision necessary for an accurate instrument measurement. In simple terms, the method detection level (MDL), which is comprised by multiplying the t

- test value for seven samples at a confidence level of 99 pe rcent (about 3) by the standard deviation obtained from seven replicate analyses, is the value above which one can say that the pollutant is present. Below the MDL, one can say the pollutant is absent. For MACT standard purposes, the MDLs from the best

- per forming sources48 are averaged together to provide the RDL. Following that the RDL is the average of the best performer’s MDLs, the RDL is about 3 times the standard deviation of the replicate analyses. With respect to instrument measurement precision, the E PA strives to make MACT standards consistent with measurement precision from new source performance standard ( NSPS ) and other MACT standards, as estimated by the American Society of Mechanical Engineer’s ( ASME’s ) ReMAP study. We find that multiplying the R DL value by three (3xRDL), or 9 times the standard deviation of the replicate analyses, yields such a consistent value, i.e., one that is within 10 to 20 percent of the relative standard deviation of the true measurement. This is why the limits
are compare d with the 3xRDL value.

With regard to a stricter measurement precision, the EPA finds the commenters suggestion to be too stringent. The Commenter suggests using 8 times the RDL (or 24 times the standard deviation of the replicate analyses) as the value t o account for measurement precision; such a value is 2.4 times larger than Lindstrom suggests as a conventional assumption for measured quantities 14 and 2.7 times larger than what the EPA uses. No changes to our methodology, or confidence intervals and meas urement precision levels will occur

Comment 2: Commenter 0248 stated for source datasets that contained below d etection limit ( BDL) or detection level limited (DLL) data, after the subcategory UPL is calculated, the EPA compares the results to “the 3xRDL v alue of the relevant performance test method(s).” MACT Floor Memo

- Brick at 9; see also MACT Floor Memo

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

“If the calculat ed 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 precisio n 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, then 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 0248 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 c eramics floor tile press dryers

• New clay ceramics floor tile spray dryers

• New clay ceramics wall tile spray dryers

• New clay ceramics tile glaze lines for Hg

14 See Limits for Qualitative Detection and Quantitative Determination , < http://nvlpubs.nist.gov/nistpubs/sp958

- lide/164

- 166.pdf >.49 Commenter 0248 stated the EPA did not “demonstrate with substantial evidence” that a 3xRDL value re presents the level achieved in practice by the best performing source or sources, as is required by CAA section 112(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 level achieved by a source; rather, according to the EPA, it is just the average of the method detection levels that were used by all th e sources the EPA considered in its floor calculations for existing sources. EPA, Data and Procedure for Handling Below Detection 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 detection 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 commente r stated therefore, a number equal to three times the RDL is not an estimate of the single best source’s emission level and cannot possibly satisfy CAA section 112(d)(3)’s floor requirements.

Response 2: 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 t he standard at a potentially unmeasurable value. The EPA used the data from the sources in each MACT floor pool to convert the standard 3xRDL value (provided in Westlin

- Merrill memo and found in the proposal docket at EPA

- HQ

OAR

- 2013

- 0291

- 0133 ) into the un its 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.50 8.0 Health

- Based Standards

8.1 Cumulative Effects

The public comments on cumulative effects can be found in section VI.C of the preamble to the Clay Ceramics final rule.

8. 2 General Support

Comment 1: Three commenters (0244, 0246, and 0247) supported the proposed acid gas health

based standard for clay ceramics manufacturing.

C ommenters 0246 and 0247 support ed the proposal to establish HF and HCl emission limitations under the proposed HCl

- equivalent limit 15 under the authority of CAA section 112(d)(4). EPA has exercised this authority in other NESHAP contexts and judicial precedent supports its exercise here. EPA considered the correct prerequisites, used well

- established, health risk

- based thresholds, and met the ample margin of safety requirement of CAA section 112(d)(4) in proposing an emission standard that assures no adverse health effects.

Commenter 0247 stated that CAA se ction 112(d)(4) provides clear authority to EPA to set health

- based emission standards. In the 1990 Senate Report discussing Section 112(d)(4), Congress wrote: “ To avoid expenditures by regulated entities that secure no public health or environmental benef it, the Administrator is given discretionary authority to consider the evidence for a health threshold higher than MACT at the time the standard is under review ..... But where health thresholds are well established, ..., and the pollutant presents no risk of other adverse health effects, the Administrator may use the threshold with an ample margin of safety (and not considering cost) to set emissions limitations for sources in the category or subcategory. Employing a health threshold or safety level rather than the MACT criteria to set standards shall not result in adverse environmental effects which would otherwise be reduced or eliminated. ” S. Rep. No. 228 (1990).

Commenter 0247 also stated that the proposed HCl

- equivalent standard is based on considerabl e data and well

- established health

- based thresholds (79 FR 75660 (cols. 1 and 2) ) . The proposed HCl

- equivalent standard will not result in adverse environmental effects that would otherwise be reduced or eliminated by the CAA section 112(d)(3) NESHAP appro ach. There will be no observable adverse effects from the proposed health

- based standard. There are no proposed exclusions from compliance. EPA considered ecosystem benefits (79 FR 75660 (col. 3)) and cumulative effects (79 FR 75661 (col. 1) )

. Response 1: The EPA appreciate s the commenters’ support for the proposed health

- based standard for acid gases.

15 79 FR 75661 (cols. 2

- 3)

- 75663 (col. 1) (Dec. 18, 2014)(proposed to be codified as Tables 1, 6 and 7 of 40 CFR 63.8555(a)).51 9.0 Work Practice Standards

Comment 1: Commenter 0 248 asserted that the work practice standards that EPA proposed to set for startup and shutdown period e missions for all clay ceramics plants, and for all emissions from clay ceramics sanitaryware shuttle kilns do not satisfy the CAA ’s requirements. The commenter’s rationale for their objection to the startup and shutdown period emissions is summarized in se ction 10.0 of this document, “Startup and Shutdown.”

Commenter 0 248 noted that section 112(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 p ollutants.” 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 pol lutant 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 not practicable due to technological and econ omic limitations.

Id . CAA section 112(h)(2). If this requirement is met, the work practice standard nonetheless must be “consistent with the provisions of subsection [112](d).” Id . CAA section 112(h)(1).

Response 1 : The EPA ’ s responses to Commenter 0 248 re garding their objection to the work practice standards for sanitaryware shuttle kilns are provided later in this section. The EPA ’ s response to Commenter 0248 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 0248 argued that EPA ’ s work practice standards for clay ceramics sanitaryware shuttle kilns are unlawful and arbitrary and violat e CAA section 7412(h) and 7412(d). The commenter provided the following reasons in support of their statement s :

1. The EPA lacked factual basis for asserting HCl breakthrough presents problem s for EPA Methods 26 and 26A. EPA lacked any information for clay ceramics sanitaryware shuttle kilns about whether HCl emissions are variable and experience large spikes, and experience breakthrough during testing. EPA only speculated that shuttle kilns “ c ould encounter a similar problem ” as brick periodic kilns. ( 79 FR 75662 ) . Even if breakthrough can occur and retesting required , that does not present a technological hurdle rendering the methods impracticable for the entire class of sources . I t only means that additional time and costs may have to be expended in some instances , which does not show that the measurement methodology is not practicable, either technologically or economically. EPA did not claim that such costs would be high, nor did EPA attempt to estimate the costs.52 2. EPA ’ s assertion that additional manpower would be required does not constitute a technological or economic limitation and EPA did not assert that the costs of the additional manpower would be high and did not attempt to estimate the costs. 3. Even if EPA ’ s asserted reasons for the impracticability of applying conventional methods to HCl and HF emissions are supportable, they do not justify work practice standards for Hg and non

- Hg HAP metals because those pollutants would be measu red through PM testing. EPA did not say that emissions of other regulated pollutants would encounter the same issue s . To the contrary, EPA acknowledged that different methods (i.e., EPA Methods 5 or 17) would be used to test for PM as a surrogate for non

- H g HAP. Work 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. ” 42 U.S.C. Section 7412(h)(1). Thus, EPA must make a supportable determinatio n that an emission standard is infeasible for each hazardous air pollutant , which the EPA has not do ne

. Also, EPA Method 320 is a practicable alternative to Methods 26 and 26A . EPA has recognized that FTIR does not present technological limitations (see 79 FR 75662 ( “ With FTIR, HCl breakthrough is not an issue. ” ) )

. The EPA is allowed to set work practice standards in lieu of numerical emissions limits only if economic limitations rendered the measurement of emissions truly “ impracticable. ” Congress required MACT

- based emissions limits be set at least as stringent as the floors, regardless of cost. The EPA had not explained why Method 320 is economically infeasible for shuttle kilns. EPA did not compare testing costs to sales or to profits and only conducted an “ informal ” analysis based on allegedly confidential business data for which they provide d no documentation showing economic infeasibility

. 4. The EPA noted that variability would interfere with stack testing ; however, the commenter noted that stack testing is a snapshot of emissions at a certain period in time, and emissions can be variable over time. The commenter noted that the variability in stack testing did not prevent EPA from using stack testing as a measurement methodology for other so urces, such as tunnel kilns. The commenter stated that EPA had
not explain why stack testing is practicable for other sources but not for shuttle kilns. 5. The EPA did not specify whether the work practice standards for emissions from clay ceramics sanita ryware shuttle kilns apply to Cl 2 emissions. The commenter asserted that i t is illegal for EPA to fail to set a standard for a hazardous air pollutant emitted by a source. 42 U.S.C. Section 7412(d)(2)

- (3); Nat ’ l Lime Ass ’ n , 233 F.3d at 634. 6. The 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 achieved by a numerical standard)

. The commenter argued, the proposed standards are not consistent with Section 7412(d) and violate Section 7412(h). The commenter noted that EPA is aware that HAP emissions are influenced by factors such as the content of surface coatings, body additives, and raw materials, and 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 [or] metallic body additives and surface coatings commonly used in the industry. ” ); id. at 47 899.

The commenter also stated that the phrase “or equivalent” in the proposed work practice standard: “ [e]ach facility would have to use natural gas or equivalent as the kiln fuel, except53 during periods of natural gas curtailment or supply interruption ” ( 79 FR 75663) is ambiguous. The commenter recommended the EPA revise the proposed language to clarify that kilns are required to use natural gas or the cleanest available fuel. Also, the exclusion for “ periods of natural gas curtailment or supply interrupti on ” would not ensure pollutant reductions consistent with the reductions that would be achieved by a numerical standard, and therefore is unlawful and must be removed.

Response 2 : The EPA disagrees with the commenter that testing of sanitaryware shuttle kilns using Method 26 or 26A poses no technological or economic limitation. The EPA also disagrees with the commenter that we did not assert that the costs of manpower to conduct the tests would be high or that we did not attempt to estimate such costs ( s ee 79 FR 75662, col. 2). As noted in the preamble to the proposed rule, c onducting a shuttle kiln test on even the shortest cycle time would require a test crew to be on site for at least 24 hours and would require the test team to have at least a dozen or more sampling train set

- ups or additional manpower on site to recover samples and turn

- around sampling trains for subsequent use during the test. It is estimated that the test of a single shuttle kiln firing cycle with analysis would cost $20,000 or more (2009 dollars). D ue 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 shuttle kiln emissions

. To collect three test runs of data, two addi tional cycles would need to be tested, bringing the cost to $60,000 or more (2009 dollars) to test a single shuttle kiln. Furthermore, because shuttle kilns are used to fire a wide variety of products that may have significantly different time

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

. Furthermore, the sanitaryware facilities covered under this proposed Clay Ceramics manufacturing rule have three or more shuttle kilns each, requiring additional tests at each facility , potentially resulting in test costs of $180,000 or more per facility. Add to that the possibility that such lengthy testing might have to be redone in the event of HCl breakthrough, and it is clear t hat Method 26/26A testing is not a practical method for testing acid gas emissions from shuttle kilns. Consequently, the rest of our analysis focused on FTIR as the only practical alternative left to review.

The same argument about cost could also be made for FTIR, since the cost for testing by FTIR is estimated to be $49,750 (2009 dollars) for a single 5 0

- hour kiln cycle (the average cycle time for a BSCP periodic kiln)

. Assuming a 50 percent reduction in cost for an average 25

- hour

s anitaryware shuttle kiln cycle, the cost to test one cycle would still be substantial (nearly $25,000 (2009 dollars)). If it were determined that the variations in emissions from cycle to cycle

were significant, it might be necessary to test each kiln for two or more cycles i n order to develop a representative emission rate. Testing for a second cycle would double the testing cost to almost $50,000 and testing for a third cycle would triple the cost to almost $75,000 (2009 dollars). In addition to these costs, additional costs would be incurred for testing the kilns for PM emissions, which would have to be tested using a manual test method , such as EPA Method 5 /17, multiple times over very lengthy periods . If additional shuttle kilns needed to be tested at each facility, the co sts would be even higher

. 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 m et.54 While no formal cost

- to

- sales analysis was conducted for sanitaryware shuttle kilns like the one conducted for BSCP periodic kilns , a similar informal analysis was performed using the sales and production data provided in the 2008 EPA survey responses

. These data were claimed as CBI by the respondent and, therefore, were not in the public record, as the commenter noted

. Regardless, b ased on this analysis, a similar conclusion (that testing is not economically feasible)

can be reached. Because the test c osts are similar and shuttle kilns represent a small share of total sanitaryware production and revenues, the EPA has concluded that it would not be economically feasible to require testing for shuttle kilns.

T he EPA disagrees with the commenter’s contention that the emissions variability for shuttle kilns is comparable to that for tunnel kilns. As stated above, shuttle kilns have variations during firing cycles and variations in emissions across tests. These va riations are substantially greater than those observed for continuously operating tunnel kilns. In addition, unlike tunnel kilns, shuttle kilns are used to fire a wide variety of ceramic products that may have significantly different time

- temperature profi les, which also increases variability for a particular shuttle kiln.

In response to the commenter’s question, the w ork practice standards for emissions from sanitaryware shuttle kilns do not apply to Cl 2 emissions . T here are no valid Cl 2 emissions data for clay ceramics facilities

. 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 disagrees with Commenter 0248 that the standards for emissions from sanitaryware shuttle kilns do not address em issions 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 periodic kilns (such as shuttle 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 sanitaryware shuttle kilns. In addition, the work practice standards for san itaryware shuttle kilns requires e ach facility
to use natural gas or equivalent as the kiln fuel , except during periods of natural gas curtailment

or supply interruption

. The term “ equivalent ” is meant to refer to a fuel with equivalent properties, which would include emissions from fuel

- burning; no clarification is needed

. With regarding to the commenter’s request for EPA to remove t he provision allowing for alternative fuel during “ periods of natural gas curtailment or supply interruption

, ” this provisio n is essential for a workable standard, because natural gas may not always be available. To ensure close monitoring of such situations, t he rule includes a provision requiring sources to submit a notification of alternative fuel use within 48 hours of the declaration of a period of natural gas curtailment or supply interruption that specifies the r eason they are unable to use natural gas or equivalent fuel, including the date when the natural gas curtailment was declared or the natural gas supply interrupti on began; the type of alternative fuel that they intend to use; and d ates when the alternative fuel use is expected to begin and end. The rule also includes a provision requiring
sources to submit a report of alternative fuel use within 10 working days aft er terminating the use of the alternative fuel. The report must include the r eason for using the alternative fuel, the t ype55 of alternative fuel used to fire the affected kiln, the d ates that the use of the alternative fuel started and ended, and the a mount of alternative fuel used.

Comment 3 : Commenter 0244 supported the use of work practice standards for shuttle kilns. However, the commenter noted that their company has not developed and does not use designed firing time and temperature cycles for each product fired in a shuttle kiln. Any shuttle kiln batch will be comprised of a variety of different products being fired together, and so only one or two batch cycle curves are developed per kiln.
Response 3 : The EPA appreciate s the commenter’s support for the use of work practice standards for shuttle kilns and agree s with the commenter regarding the need for clarification. T he work practice standards in Table 3 have been revised for the final rule accordingly. Similar text has also been revised in 40 CFR 63.8640(c)(7)(i)

- (ii), Table 6 and Table 7 for the final rule.56 10.0 Startup and Shutdown

The significant public comments on startup and shutdown can be found in section VI.D of the preamble to the Clay Ceramics final rule. The remaining public comment and EPA’s response is presented in this section.

Comment 1: Commenter 0248 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 sections 112(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
t hat because the EPA does not claim or demonstrate that measurement is impracticable for the categories of brick, or for subcategories of clay ceramics kilns as a class, the proposed work practice standards are unlawful.

Commenter 0248 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 CAA section 112(h) that either section 112(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 that EPA believes work practice standards are authorized under section 112(h)(2)(A), the EPA does not “determine[]” that a pollutan t “cannot be emitted through a conveyance designed and constructed to emit or capture such pollutant” during startup shutdown periods. The absence of the requisite statutory determination under section 112(h)(2) by the Administrator alone renders the propo sed work practice standards unlawful.

Commenter 0248 further stated that the EPA has not satisfied the statutory requirement that 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 (appl ying 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 112(h)(2)(A), nor do they amount to substanti al evidence that it is not practicable to apply measurement technology during startup and shutdown periods under CAA section 112(h)(2)(B). The commenter stated that the EPA has not considered whether measurement methods other than the ones the EPA is propo sing 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 measu re each type of hazardous air pollutant. The EPA must select a different method for such periods, or make and support with substantial evidence a determination that no such method is available. Work practice standards are permitted only where it is entirel y “infeasible to prescribe or enforce an emission standard,” not just infeasible during certain periods.57 Commenter 0248 noted that the EPA has not claimed that CEMS 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 technologically feasible. Methods of estimating emissions during startup and shutdown, such as emission estimates based on the operating parameters of PM controls, could substitute f or the direct monitoring of emissions.

Commenter 0248 stated that the problem the EPA identifies with using the “equivalent” emission limits during startup and shutdown is irrelevant to the statutory standard, which is whether use of measurement methodolog y “is not practicable due to technological and economic limitations.” Id . CAA section 112(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 technologic ally practicable for application to kilns during startup and shutdown. The commenter 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 provid e the other “equivalent” emission limits, and if such limits are inappropriate for 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 n ot required by the Act), and then point to them as a reason why MACT standards cannot be set for periods of startup and shutdown.

Commenter 0248 further stated that even if the EPA’s startup and shutdown work practice standards for plants with air pollutio n control devices ( APCDs ) are valid, concerns about those sources’ ability to vent exhaust through the control devices lend no support to setting work practice standards for sources that do not employ control devices.

Commenter 0248 stated that the EPA’s p roposed work practice standards for startup and shutdown periods contravene CAA section 112(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 112. The EPA provides no basis for assuming that sources operating during startup and shutdown periods would necessarily meet the pertinent section 112(d) numeric limits. Under the proposed work pra ctice standards, sources would not be required to engage their pollution 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 t he sources are not feeding bricks into the kiln, they will be burning fuel during those time periods, which will result in hazardous air pollutant emissions that might be higher than the numerical limits.

Commenter 0248 stated that the D.C. Circuit has spe cifically held that the CAA requires that “there must 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 112

- compliant work practice or other emission standard to limit the rate of emissions during 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 mode58 to prevent the startu p 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 work practice standards for periods of startup and shutdown. As discusse d later in this section, the EPA has revised the work practice standards for periods of startup and shutdown for clay ceramics kilns to provide requirements for minimizing emissions that are feasible for all kilns.

The EPA disagrees with Commenter 0248 tha t 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 sources. The standards were set for ceramic tile roller kilns and sanita ryware tunnel kilns, which are sources in the clay ceramics 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 pr oposed rule,

“ we recognize that it is not feasible to conduct emission testing during periods of startup and shutdown. ” 79 FR 75647.

The EPA further disagrees with Commenter 0248 that EPA must also demonstrate that a pollutant “ cannot be emitted through a conveyance designed and constructed to emit or capture such pollutant ” during startup and shutdown periods . Section 112(h)(1) allows work practice standards only if pollution is not emitted through a conveyance or “ the application of measurement methodolog y to a particular class of sources is not practicable . (emphasis added) As noted in the previous paragraph, the EPA has already demonstrated the latter.

T he EPA has revised the standards for promulgation for both the BSCP and clay ceramics categories , base d 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 in both categories

. T he EPA is confident that these standards will provide the maximum limitation of emissions possible during periods of startup and shutdown, ensuring that the Clay Ceramics Manufacturing NESHAP includes continuous section 112

- compliant standards during all periods of operation.

Comment 2: Commenter 0250 asked that the rule language be modified in sections 63.8555 and 63.8 570 (a) to include an exclusion from the numeric limit for periods of startup and shutdown

. In support of this request for the rule language change, Commenter 0250 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 of the MAC T emission limits established for normal operations during startup and shutdown
events. Commenter 0250 stated the following concerns:

• It is not apparent from the preamble discussion of alternate standards for startup and shutdown periods that the EPA has a ctually analyzed sufficient data on emissions during startup and shutdown to justify the Agency’s conclusion that, “the EPA has taken into59 account startup and shutdown periods.” 79 FR 75626. Instead, based on the EPA’s statements about the timing of startu p 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 several 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 cause the EPA to understate emissions.

o To the extent emissions da ta 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, shutdo wn, or malfunction event. 16

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 reflectin g 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 data, because the pollutant concentration may be outside of the moni toring equipment’s span or the stack conditions may not meet monitoring system quality assurance/quality control ( QA/QC ) parameters, or the data may be truncated on the high end because of limitations of the monitoring equipment. 17

Commenter 0250 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 analyzin g 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 commenter that we are r equiring 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 work practice standa rds to apply during periods of startup 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: Commenter 0250 assert ed that emission limitations should not apply at all time s, as is implied in 40 CFR 63.857 0(a). The commenter noted that although the Sierra Club v. EPA (D.C. Cir. 2008) decision recognized that different standards, including non

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

- standard operating conditions, the Sierra Club

16 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).

17 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).60 decision does not prevent EPA from adopting emission standards for SSM periods that are different from those required during periods of normal operation. The commente r stated that the Sierra Club decision does not bar the 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 Cl ub 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 sit uation 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 adopting different emission limitati ons that apply during SSM events.

Commenter 0250 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 decision for this case is consisten t with Essex Chemical and the other NSPS cases. In Cement Kiln Recycling Coalition , the D.C. Circuit court decided to vacate the standards partly because of the Court’s concerns about EPA’s failure 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 mal function 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 t o that decision, EPA revised the rule to exempt facilities from the limitations during SSM events. See 40 CFR 68.1206(b)(1); 67 FR 6792, 6798, 6813 (February 13, 2002).Commenter 0250 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 proposed SSM provisions. The commenter argued that the Sierra Club decision did not address what the EPA may or may not include in category

- specific MACT standards. The commenter noted that court decision s 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 perfor mance 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 the standards, and that will “only result[] if ‘a chieved 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 combustors from numerical emission limits during SSM periods and the Court’s “similar doubts about EPA’s decision to require sources to comply61 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 fr om applying different standards during SSM events than 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 standard 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 infeasible 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 standard during SSM events. They stated that for 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 there is nothing in the legisl ative history of the 1977 amendments to the CAA that suggests 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 sp ecial SSM provisions in standards issued under section 111 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 the Sierra Club decision did not addr ess 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” in CAA section 302(k), in lieu of a numerical emi ssion 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 (See 551 F.3d at 1028) but argued in that case tha t section 112(h) was irrelevant to its authority to exempt excess emissions during SSM events (see Id . at 1030 (Randolph, J. dissenting)).

Commenter 0250 stated that under CAA section 112(d)(2), MACT emission standards, including those that apply during SS M events, must be “achievable” with available technology, “taking62 into consideration the cost of achieving such emission reduction, and any non

- air quality health and environmental impacts and energy requirements.” An emission limitation that applies durin g 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 that emission limitation during SSM events. The com menter argued the EPA cannot 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 0250 explained that the courts have recognized th at 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.2 d 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 fac tors 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 “necessa ry 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 requir ement that NSPS be “achievable” means that the standards must be capable of being met “on a regular basis,” including “under most adverse circumstances which can reasonably be expected to recur,” including during periods of SSM. 627 F.2d at 431 n.46.

Comme nter 0250 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 efflue nt limitations because of conditions “beyond the control of the permit holder,” EPA had violated the Clean Water 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 a lso

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

- based effluent limitations, where some provision for “upsets” is required, and water

- quality

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

The commenter asserted 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 sup port 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, operator 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 un usual types of events. Moreover, most of the cited events would not constitute

“ malfunctions, ” as EPA defines 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 wi th inadequate63 staffing during a strike) or would constitute “ careless operation ” (e.g., operator intoxication). 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 through no fault of the permittee, and which endorsed Marathon Oil

. Response 3: Exemptions for startup and shutdown are inconsistent with the holding in Sierra Club that emissions limitations under section 112 must apply continuously. The Sierra Club decision does not constrain our authority to prescribe unique standards or work pract ice 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 pe riods. 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 combin ation 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 m ake 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

- numer ic 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.
Contrary to the commenter’s argument, we believe that the standards that apply during star tup 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 no t 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 letter, our initial analysis indicated that certain rules, such as the mineral wool prod uction 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 direc t 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 legality 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 provision s and determined that they need to be revised to address the Sierra Club decision.
We disagree with commenter’s claim that case law under the CAA and CWA supports its argument that EPA’s approach to startup and shutdown periods is inconsistent with CAA sec tion 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 determining appropriate standards. The64 relevance of Portland Cement and Essex Chem. Corp. is questionable i n 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 hav e effectively repealed the regulations permitting flexibility to account for startups, shutdowns and malfunctions regulations applauded by this court in Portland 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 N RDC 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 periods. Further, the regulatory affirmative defense included in today’s final ru le 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 approach 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 re ly on enforcement discretion alone, but specifically promulgates an affirmative defense in the FIP, which clearly defines the requirements to avoid penalties.”). But see, Weyerhaeuser v. Costle , 590 F.2d 1011, 1057

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

Comment 4 : Commenter 0244 requested that EPA revise the work practice standards for startup/shutdown in Table 3: Item s 2.a.i and 3.a.i, to replace the term “ ceramics ” with

“ greenware ceramics ” to denote unfired ware. It is a sta ndard operating procedure for previously fired ware and/or refractory material to be run into a kiln to facilitate start

- up and shutdown, and these materials do not emit HAP. Adding these materials to a kiln upon start

- up or shutdown is not a violation of the proposed MACT.
Response 4 : The startup and shutdown work practice standards in Table 3 have been revised for promulgation and no longer include the term “ceramics,” so the requested revision is no longer applicable.65 11.0 Malfunction

Comment 1: Comment er 0250 stated that it is not possible to test during a malfunction. The commenter 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 standards.
Response 1: With respect to the commenter’s suggestion that the EPA consider work practice standards for periods of malfunction, the decision to use a work practice standard is wholly within the discretion of the EPA. CAA sect ion 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 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.

It is just as difficult to establish a work practice standard for malfunctions 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 single work practice standard that applies equally to a tank explosion as it does to innumerable types of operator error, compu ter glitches or a myriad of other unknown events, or alternatively create innumerable work practice standards.

In summary, the EPA believes that, based on this rulemaking record, it would be clearly inappropriate to set a work practice standard for malfunc tions in lieu of the otherwise applicable numerical emission limit. We also note that we would consider any response to violations caused 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 seek administrative penalties for excess emissions caused by malfunctions

.

Comment 2: Commenter 0250 stated that CAA section 112 does not require or even allow the EPA to ignore malfunctions when setting 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, congressional 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 str ingency of the emission standards that apply during normal, steady

- state operations

. Commenter 0250 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 cutting66 back the process accordingly) that represent the best practices fo r 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 0250 stated that facility

- specific best practices represent the “the maximum 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 simila r source[s]” CAA section 112(d)(2) and (3)

.

Commenter 0250 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 862

- 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 comme nter 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 beyond 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 concu rred with this comment.

Commenter 0250 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 envir onmental impacts and energy requirements, ” as required by CAA section 112(d)(2).

Commenter 0250 stated the EPA should include emissions data representing malfunctions (if such data exist) in calculating the MACT floor (see 79 FR 75626) or considering alter native work practice standards, instead of requiring that the 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 consider those data in its MACT floor calculations for 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 emission s 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 achi evable 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 stated t hat 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.67 Commenter 0250 stated that before affirmative defense was struck down, the Agen cy 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 to tre at 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 standard s that would apply during malfunctions. They argue that this approach would be consistent with NRDC v. EPA

. Commenter 0250 stated that the EPA’s statement “. . . the EPA would determine an appropriate response based on, among other things, the good faith e fforts 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 whether t here 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 language, 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 determin ation regulations (here startup, shutdown and malfunction), or otherwise.”). 18

Commenter 0250 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 defen d itself from a citizen suit or state enforcement action for the same malfunctions, nor does the Agency 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 comm enter noted that after

- 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 recommend ed that the EPA address compliance during malfunctions by promulgating an achievable alternative standard.

Commenter 0250 noted in a district court enforcement action or in a citizen enforcement action, “similarly, the presiding officer in an administrativ e 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

18 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.68 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 Clean Air Act violations extends only to administrative penalties, not to civil penalties imposed b y 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.

Commenter 0250 noted that in the portion of the pro posed 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 2: The EPA disagrees 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 require 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

- performing 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 ab out how the performance 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 no t impossible, given 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 solve 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. ’” )

With respect to the commenters ’ suggestion that EPA consider work practice standards, we refer to our response to the previous comment.

Comment 3: Commenter 0250 noted that in the proposed rule, the EPA replaced the NESHAP General Provisions section that establishes a “general duty” to operate a source con sistent 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 the69 preamble to the Proposed Rule, 40 CFR 63.6(e )(1) does not 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 rule 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 provisio n 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 3: 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 e vents in describing the general duty. 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 63.8420(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 proposed 40 CFR 63.8420(b) deleted from the final rule. Reproposal of the section, with some explanation of the basis and purpose for the provision, is also unnecessary and is denied.

Comment 4 : Commenter 0247 stated the EPA has taken inconsistent positions on what a

“ malfunction ” is and is not, and how emissions during periods of “ malfunction ” should be handled by this industry. On the one hand, EPA chooses not to define a malfunction for purposes of creating a distinct continuous compliance approach during periods of malfunction separate from normal operations, stating that the CAA does not require it to separately regulate emissions during malfunctions, 79 FR 75626 (cols

- 2

- 3)), leaving open the question, of what exactly a malfunction is.

The commenter argued that EPA ’ s proposal f orces malfunctions

- related emissions to meet the same requirements as normal operations, despite EPA stating that malfunctions are not normal operations . E missions during these periods are “ neither predicable nor routine. ” Id . Malfunctions

are “ sudden, inf requent and not reasonably preventable failures of emissions control, process or monitoring equipment. ” Id . EPA draws the comparison to “ upsets ” in other regulatory programs as the basis for its proposed choice not to define malfunctions ( 79 FR 75626 (col. 3) ) . While upsets were at one time difficult to define, definition has occurred.

The commenter noted that, in other places in the proposed NESHAP, EPA treated malfunctions as if it defined them. For example, EPA prohibited performance testing during “ malf unctions ” ( 79 FR 75696 (col. 2) ; proposed to be codified at 40 CFR 63.8595(d)). Also, EPA asserted that emissions during malfunction periods must be excluded in determining a MACT floor ( 79 FR 75627). EPA proposed that an exceedence of an emission limit or an operating limit during a

“ period of malfunction ” is a reportable Title V deviation ( 79 FR 75699

- 75700 ; proposed to be70 codified at 40 CFR 63.8620(c) and 63.8635(g)). The commenter argued the EPA leads the reader to the conclusion that EPA has defined ma lfunctions.

Commenter 0247 stated that EPA ’ s reliance on after

- the

- fact legal enforcement does not assure the continuous compliance required by the Courts. EPA has twice recognized that malfunctions occur; the fact that the Courts have twice struck down EP A ’ s attempts to acknowledge and address them in the NESHAP context (the Sierra Club case, and as an affirmative defense), does not mean that malfunctions do not occur, or that EPA is out of options for accommodating malfunctions. EPA has recognized for dec ades that malfunctions and upsets are part manufacturing and has judicial approval for New Source Performance Standards ( 40 CFR 60.8 (2014) ) that accommodated such events . The CAA has several provisions pursuant to which EPA can take the actions

. See NRDC v. EPA , 859 F.2d 156, 208 (D.C. Cir. 1988).

The commenter argued that EPA cannot write inconsistent regulations. The commenter encouraged EPA to develop and propose a definition of malfunction that will be used consistently throughout the NESHAP for this subcategory so that the regulated community is able to clearly understand what behaviors are lawful and what behaviors are prohibited. With no definition of a malfunction, the commenter argued, the public cannot comment on the emission standards proposed b y EPA. The commenter contended that the regulation, if finalized as proposed, would be arbitrary and capricious.

The commenter stated that it is only by reasonably defining malfunctions and creating a meaningful, achievable continuous compliance option dur ing them that EPA can avoid the inclusion of those emissions in the MACT floor. If emissions during malfunctions are deemed to be emissions during normal operations for compliance purposes, they must also be considered to be emissions during normal operati ons for purposes of setting the MACT floor pool. They would likewise be eligible for performance testing. If emissions during malfunctions are not deemed to be emissions during normal operations and separate standards are set, EPA may avoid these
outcomes it states in the preamble it is trying to avoid.

I f HAP emissions during periods of malfunction must comply with the same emission limits applicable to normal operations, EPA can expect major sources to report deviations in most title V certification repo rts. EPA has a strong incentive to define malfunctions in this rule to avoid that situation. Sudden and un preventable failures of emissions control, process or monitoring equipment are far from routine but they are not rare either. Even best performing sou rces have malfunctions.

Response 4 : These comments are based on two incorrect premises. First, contrary to the
commenter ’ s statements, the EPA has defined malfunctions, in 40 CFR 63.2, and does not need to define malfunctions further for this rule. Second, the EPA does not need to factor emissions that occur during malfunctions into the emiss i ons standard, or develop a different emissions limit or other special rules for malfunctions. The EPA interprets CAA section 112 as not requiring emissions that occur during periods of malfunction to be factored into development of CAA section 112 standards. Under section 112, emissions standards for new sources must be no less stringent than the level “achieved” by the best controlled similar source and for existing so urces generally must be no less stringent than the average emission limitation “achieved” by the best71 performing 12 percent of sources in the category. There is nothing in section 112 that directs the Agency to consider malfunctions in determining the leve l “achieved” by the best performing sources when setting emission standards. As the D.C. Circuit has recognized, the phrase “average emissions limitation achieved by the best performing 12 percent of” sources “says nothing about how the performance 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). While the EPA accounts for variability in setting emissions standards, nothing in section 112 requires the Agency to consider malfunctions as part of that analysis. A malfunction should not be treated in the same manner as the type of variation in performance that occurs during routine operations of a source. A malfunction is a failure of the source to perform in a “normal or usual manner” and no statutory language compels EPA to consider such events in setting section 112 standards. Further, accounting for malfunctions in setting emission standards would be difficult, if not impossible, given 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. As such, 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 solve a problem. We generally defer to an agency ’ s decision to
procee d on the basis of imperfect scientific information, rather than to ‘ invest the resources to conduct the perfect study. ’” ) See also, Weyerhaeuser v

. Costle , 590 F.2d 1011, 1058 (D.C. Cir. 1978) (“ In the nature of things, no general limit, individual permit, or even any upset provision can anticipate all upset situations. After a certain point, the transgression of regulatory limits caused by ‘uncontrollable acts of third parties,’ such as strikes, sabotage, operator intoxication or insanity, and a var iety of other eventualities, must be a matter for the administrative exercise of

case

- by

- case enforcement discretion, not for specification in advance by regulation.”). In addition, emissions during a malfunction event can be significantly higher than emis sions at any other time of source operation. For example, if an air pollution control device with 99 percent removal goes off

- line as a result of a malfunction (as might happen if, for example, the bags in a baghouse catch fire) and the emission unit is a steady state type unit that would take days to shut down, the source would go from 99 percent control to zero control until the control device was repaired. The source’s emissions during the malfunction would be 100 times higher than during normal operatio ns. As such, the emissions over a 4

- day malfunction period would exceed the annual emissions of the source during normal operations. As this example illustrates, accounting for malfunctions could lead to standards that are not reflective of (and significan tly less stringent than) levels that are achieved by a well

- performing non

- malfunctioning source. It is reasonable to interpret section 112 to avoid such a result. The EPA’s approach to malfunctions is consistent with section 112 and is a reasonable interp retation of the statute.

In the event that a source fails to comply with the applicable CAA section 112(d) standards as a result of a malfunction event, the EPA would determine an appropriate response based on, among other things, the good faith efforts o f 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. The EPA would also consider whether the source ’ s failure to comply with the CAA section 112(d) standard was, in fact, sudden, infrequent, not reasonably preventable and was not instead caused in part by poor maintenance or careless operation. 40 CFR 63.2 (definition of malfunction).72 If the EPA determines in a particular case t hat an enforcement action against a source for violation of an emission standard is warranted, the source can raise any and all defenses in that enforcement action and the federal district court will determine what, if any, relief is appropriate. The same is true for citizen enforcement actions. Similarly, the presiding officer in an administrative proceeding can consider any defense raised and determine whether administrative penalties are appropriate.

In summary , consistent with Sierra Club v. EPA , the EP A has established standards in this rule that apply at all times, including periods of malfunction. The EPA interpretation of the CAA and, in particular, section 112 is reasonable and encourages practices that will avoid malfunctions. Administrative and ju dicial procedures for addressing exceedances of the standards fully recognize that violations may occur despite good faith efforts to comply and can accommodate those situations.

Comment 5 : C ommenter 0247 argued that the regulated community can assert def enses to malfunction

- related emissions in excess of emission limits applicable during normal operations, citing Weyerhaeuser v. C o stle , 590 F.2d 1011 (D.C. Cir. 1978). “ The source can raise any and all defenses, ” the preamble declares ( 79 FR 75627 (col. 1) ). The proposed NESHAP regulation, however, made no defenses legally available. The preamble suggested defenses such as good faith efforts to minimize emissions, including preventative and corrective actions, as well as root cause analyses. The commenter s tated it is “ illusory, arbitrary and capricious for EPA to assert in a preamble that defenses are legally available and then not to include those defenses in its regulation. ” The commenter also noted that a common definition of “ malfunction ” for compliance and enforcement purposes is also necessary . The commenter contended that EPA ’ s proposed approach create s a new enforcement process for NESHAPs that worsens the situation and violates Executive Orders.
Response 5 : We disagree with the commenter’s contention that the EPA is obligated to create a regulatory affirmative defense that would protect a source that fails to comply with the applicable CAA section 112 standards as a result of a malfunction event. Though EPA has in the past included such an affirmative defense in some rules, the United States Court of Appeals for the District of Columbia Circuit recently vacated an affirmative defense in one of the EPA’s Section 112 regulations. NRDC v. EPA , 749 F.3 d 1055 (D.C. Cir., 2014) (vacating affirmative defense provisions in Section 112 rule establishing emission standards for Portland cement kilns). The court found that the EPA lacked authority to establish an affirmative defense for private civil suits and held that under the CAA, the authority to determine civil penalty amounts in such cases lies exclusively with the courts, not the EPA. Specifically, the Court found: “As the language of the statute makes clear, the courts determine,

on a case

- by

- case basis , whether civil penalties are ‘appropriate.’” See NRDC at 1063 (“[U]nder this statute, deciding whether penalties are ‘appropriate’ in a given private civil suit is a job for the courts, not EPA.”). In light of NRDC , the EPA is not including a regulatory a ffirmative defense provision in the final rule. If a source is unable to comply with emissions standards as a result of a malfunction, the EPA may use its case

- by

- case enforcement discretion to provide flexibility, as appropriate. Further, as the D.C. Circ uit recognized, in an EPA or citizen enforcement action, the court has the discretion to consider any defense raised and determine whether penalties are appropriate. Cf. NRDC , at 1064 (arguments that violation were caused by73 unavoidable technology failure can be made to the courts in future civil cases when the issue arises). The same is true for the presiding officer in EPA administrative enforcement actions.

Comment 6 : C ommenter 0247 argued that EPA attempted to justify its proposed approach to malfunctio ns on the Court ’ 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 EPA ’ s proposal may be at odds with that decision since t hat case struck down a portion of the NESHAP General Pr ovisions and NESHAP category

- specific requirements were not before the Court. The Court did not rule that category

- specific emissions limitations must be the same for periods of normal operations and periods of malfunction because malfunctions are a challenging subject or difficult to define.
Response 6 : We disagree with the commenter’s suggestion that Sierra Club v. EPA , 551 F.3d 1019 (D.C. Cir. 2008) is not relevant because it addressed the SSM exemption in the NESHAP General Provisions and did not address what EPA may or may not include in category

- specific MACT standards. The holding in Sierra Club that emissions limitations under section 112 must apply continuously is clearly applicable to category

- specific MACT standards. Moreover, as discussed a bove, the EPA’s approach to malfunctions in this rule is consistent with the D.C. Circuit’s decision in NRDC v. EPA , 749 F.3d 1055 (D.C. Cir. 2014).

Comment 7 : According to C ommenter 0247 , CAA section 112(d) and the courts require establishment of NESHAP standards that can be achieved in practice by the regulated community. The commenter contended that EPA failed to survey the industry on this subject, as it surveyed other subcategories, and thus it has almost no basis for its implied conclusion that durin g a period of malfunction, major sources in this subcategory achieve in practice emissions limitations established on the basis of stack testing during normal operations. The commenter disputed that major sources in this subcategory always achieve such emi ssions limitations during periods of malfunction. The commenter stated that EPA ’ s proposal legally must be considered a beyond

- the floor proposal, which has not undergone that analysis. Therefore, the commenter concluded it is unlawful.

Commenter 0247 indi cated that their organization provided EPA with PM emissions data for a floor tile kiln during periods of malfunction ( see 79 FR 75627 (col. 2) ) and the citation therein to EPA ’ s “ 2010 EPA Survey. ” (Dec. 18, 2014). EPA could have developed a PM surrogate

e missions limitation for periods of malfunction from these data. Courts have indicated that EPA has the authority to develop NESHAP emissions limitations during periods of malfunction when it has actual relevant emissions data. The commenter contended that EPA ’ s failure to develop a PM surrogate emissions limitation for floor tile kilns during periods of malfunction is arbitrary and capricious.

By analogy, the commenter also noted that EPA had the opportunity to develop D/F and Hg emissions limitations for f loor tile kilns during periods of malfunction, and failed to do so. The commenter stated that failure is also arbitrary and capricious.

Re sponse 7 : As explained in the preamble of the proposed rule, the EPA has determined that CAA section 112 does not require that emissions that occur during periods of malfunction be factored into development of CAA section 112 standards. While the EPA accounts for variability in setting emissions standards, a malfunction is a failure of the source to perform in a ‘‘nor mal or74 usual manner’’ and no statutory language compels the EPA to consider such events in setting section 112 standards. Further, accounting for malfunctions in setting emission standards would be difficult, if not impossible, given the myriad different t ypes 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. Consequently, we disagree with the c ommenter that a survey of the industry on the subject of malfunctions would have produced data sufficient to establish standards that account for all possible malfunctions in the industry, or that we could have used the data they provided from one kiln for one pollutant for a limited number and type of malfunctions to establish standards that account for all possible malfunctions in the industry.75 12.0 Testing and Initial Compliance Requirements

Comment 1: Commenter 0244 argued that the temperature operati ng limit listed in Table 2 for sanitaryware kilns does not account for normal temperature variability in a tunnel kiln and is unnecessarily restrictive. The commenter requested the temperature limit be set at a temperature above 2000 degrees F. Alternative ly, the commenter suggested the temperature limit be the 3

- hour block average measured during the performance test minus 100 degrees F. The commenter stated that such a limit would not comprom ise compliance with the MACT.

The commenter argued that some fl exibility in the temperature operating limit is necessary to account for normal variability and to allow kiln processes to operate in a manner that meet s market demand

, minimize s scrap, fuel consumption and greenhouse gas emissions, and allow s process inno vation and optimization.

According to the commenter, scientific literature recognizes incineration as the best available method to destroy dioxins/furans and noted The World Health Organization ’ s Fact Sheet No. 225 (Dioxins and Their Effects on Human Healt h

- June 2014) states that most published research
papers on D / F control indicate temperatures over 1000 degrees C (1830 degrees F) are effective for D/F destruction. F irst

- fire tunnel kilns operate at over 2000 degrees F and therefore, continuous compliance with the D/F emission limitation can be assured by maintaining the peak kiln temperature at 2000 degrees F. The commenter requested the operating limit in Table 2 : Item 5.c, be changed to reflect this minimum operating temperature lim it . The commenter noted the same format was used in t he Clay MACT area source rule (s ubpart RRRRRR) , where kiln temperature was limited to a maximum of 2800 degrees F and kilns must be fired by natural gas or equivalent. Subpart RRRRRR shows a precedent fo r this type of format for a temperature operating limit.

The commenter also noted that peak kiln temperature has some normal day

- to

- day variation and provided time

- temperature plot for the ir first

- fire tunnel kiln in Wisconsin. This plot shows the same fir ing cycle on two different days is almost 20 degrees C (68 degrees F) different. The commenter noted that e stablishing an operating limit for peak temperature will be problematic because it does not account for normal variability.

According to the commente r, kiln temperature is also related to ware throughput . A s throughput rates are reduced, operating temperatures can also be reduced, leading to a situation where a kiln could violate the temperature operating limit when it scales back production below the level achieved during the performance test.

The commenter also provided a pyrometric cone chart from a kiln operating manual show ing that the temperature variation between fast and slow cycle times can be up to 100 degrees F for any specific cone number be tween cone 6 and cone 10. The chart shows that as kilns migrate from a fast cycle cone 10 schedule to a slow cycle cone 6 schedule, the peak temperature in the same kiln can drop by over 200 degrees F.

Commenter 0244 stated it is normal for peak kiln tempe rature s to fluctuate as much as 50 degrees F from fast to slow cycle times and provided time

- temperature plots showing the temperature fluctuations for two of their tunnel kilns. The commenter also noted that kiln76 temperature is also controlled to meet certain industry standards , such as sanitaryware products that are required to meet the ASME A112.19.2 plumbing fixture standard for sale in the United States and Canada. Chapter 6.1 of this standard requires all ware to meet a maximum water absorption spe cification. Ware that exceeds this maximum specification must be scrapped. Fired ware is checked daily against this specification, and kiln temperature is managed to minimize water absorption of fired ware. Sanitaryware facilities need flexibility to manag e kiln temperature to meet these types of industry standards.

Commenter 0244 stated their company operate s its processes as energy efficiently as possible and investigat es process alternatives that may allow vitrification to occur at lower temperatures. Ev en a minor temperature reduction at a kiln can represent a significant reduction in fuel use, with an equivalent reduction in greenhouse gas emissions. The commenter stated that facilities need flexibility to pursue process strategies without having to rep eat performance testing. Commenter 0244 noted that vitreous sanitaryware plants are highly integrated and noted that it takes considerable time (many weeks) to increase production across a facility so that performance testing can be completed

.

Commenter 02 44 further stated that more information is needed on how redoing performance tests to set new operational limits can be completed without violating the MACT/permit (Table 4: Item 4.a)

. For instance, the source operator may need to decrease production from t hat measured during the previous performance test, which may lead to an operating temperature below the previously established minimum

. T he commenter asked how that can be accomplished without violating the minimum temperature limit established in the pri or performance test

, noting that i t can take several weeks to optimize a new throughput cycle

. W hile this is being done, the kiln may be in non

- compliance (under the minimum temperature limit measured during the previous performance test) as it migrates to the new throughput rate. The commenter asked how this should be handled for MACT compliance demonstration purposes. The commenter requested a temporary waiver be available for a source so that when kiln cycle changes are implemented they do not result in periods of non

- compliance until the performance test is redone. The commenter asserted that the optimization period should not be considered non

compliant operation unless a subsequent performance test documents it to be. The commenter stated that their re quest to establish a minimum temperature operating limit at 2000 degrees F would resolve any compliance issues on this matter, and still allow compliance with the dioxin/furan emission limit to be demonstrated.
Response 1 : New operational parameter s are set by completing a performance test to demonstrate compliance and by establishing the new operating parameters that correspond with that compliance demonst r ation

. Thus, if a source wishes to change its operating practices such that it will no longer meet its applicable operational limits, the source must conduct performance testing at the time that it makes the operational change and must establish the new operating parameter limits that will be used to monitor compliance. Until the results of the performa nce test under the new operational conditions confirm that the facility is in compliance, the facility should continue to meet the original operational parameters

. On a related point, b ecause the kiln temperature can vary and no quenching is occur r ing in t he process system, a better parameter for demonstrating compliance would be the stack temperature. Dioxins and f urans are known to form in post

- combustion gases in temperature ranges of 200 to77 400 degrees C (392 to 752 degrees F), 19 so assuring that the maximum stack temperature recorded during the compliance test is never exceeded will assure that the dioxin limit is continuously met. Therefore, we are revising the requirement by basing the performance parameter on the stack temperatur e and not the kiln temperature.

Comment 2 : Commenter 0247 argued th e initial (for D/F ) and subsequent (for all proposed HAP ) performance testing is unlawful and unnecessary due to issues with EPA Method 23 and duplication of ongoing Compliance Assurance Monitoring (CAM) and the proposed CPMS. The commenter objected to the proposed requirement to conduct initial and subsequent D/F compliance testing using Method 23 ( 79 FR 75695 (col. 3)

- 75696 (col. 1) ; proposed t o be codified at 40 CFR 63.8590) because of issues with the reliability, accuracy and validity of Method 23. Until M ethod 23 or another method is developed and validated by EPA for use in the context of the ball clay matrix found in the ceramic tile manufa cturing industry, the commenter contended there is no lawful means to set a D/F standard or to measure compliance.

The commenter also challenged subsequent performance testing, whether within five years after NESHAP

- proposed initial compliance testing or i n connection with the proposed renewal of a Title V permit ( 75,695 (col. 3)

- 75,996 (col. 1) )

. The proposed subsequent performance testing is duplicative since it overlap s EPA ’ s CAM program and is unnecessary given the results that EPA anticipates will be d erived from the proposed CPMS. EPA offers no explanation and suggests no value

- added associated with subsequent performance testing. EPA and delegated states retain discretionary authority to require stack testing where emissions problems at a specific fac ility are reported or evident. This proposed expensive subsequent performance test will be an unnecessary burden on the regulated community that EPA has not justif ied, and is arbitrary and capricious.

Commenter 0247 recommended the EPA adopt the approach t aken to stack testing in the March 2010 ICR. Major sources should have the option to designate like sources as representative and to test the compliance status of one, or at least fewer than all of them. Since this was acceptable to EPA in the ICR context, the commenter saw no valid objection to the continuation of this practice. Failure to allow designation of like sources and to consider testing results to be representative would be arbitrary and capricious.

Response 2 : The EPA di sagrees with th e comment er , since i nitial compliance testing and follow

- up testing for D/F are necessary for showing compliance with the emission limit

, setting the CAM requirements

, and complying with the proposed CPMS operating limits.

The EPA also disagrees with the commenter’ s contention that

, because the ICR did not require testing of every stack at a facility, compliance status should be demonstrated by representative

sources. ICR s are used to gather information . However, actual stack testing after promulgation is required t o demonstrate compliance. Choosing several sources for compliance status is not an option , since it is unknown whether the remaining facilities are in compliance. Each source is

19 Observations on the Effects of Process Parameters on Dioxin/Furan Yield in Municipal Waste and Coal Systems, Gullett, Brian K. and Raghunathan K., Chemosphere, Vol 34 Nos 5

- 7, p. 1027, 1997.78 different and will have different test results. For compliance

, it is essentia l to have stack tests for each source

.

Comment 3 : Commenter 0247 argued that proposed Table 4, rows 2 and 11 impose erroneous PM performance test requirements on glaze spray operations. The glaze spray operations in this subcategory occur in a “ glaze spray booth, ” as defined in proposed 40 CFR 63.8665 (commonly described in the ceramic tile manufacturing industry as a “ cabinet ” ). Baffles at the entry and exit of these cabinets keep sprayed glaze in the cabinet.

The commenter noted that EPA proposed to regul ate HAP emissions from those glaze lines at major source ceramic tile manufacturing facilities whose glaze spraying operations emit HAP

, unless the spray glazes used in those operations satisfy the proposed exemption in 40 CFR 63.8540(c)(3), Table 1, rows 5 and 15. 20 EPA refers to the entire glaze line over twenty times in the preamble and in the proposed NESHAP, most critically in the emission standards presented in proposed Table 1, rows 5 and 17, 21 and the comparable provisions in Tables 6 and 7.

Commenter 0247 stated that EPA must alter proposed Table 4, rows 2 and 11 to meet its intentions 22 and to assure consistency with Table 1. Table 4 proposes measurement of emissions from glaze spray operations. Th e se requirements should be deleted because compliance is not measured for the glaze spray operations standing alone; it is measured for the entire glaze line, Table 1, rows 5 and 15. 23 HAP emissions, if any, from glaze spray operations are irrelevant to the Table 1 compliance determination. Moreover, in most c eramic tile manufacturing facilities, emissions from glaze spray operations are not separately routed to a pollution control device; they are commingled with emissions from other glazing line activities and routed to a common control device. Thus, their ph ysical measurement independent of those other activities is unworkable. F ailure to delete the Table 4 performance testing requirements for glaze spray operations would be arbitrary and capricious.

Response 3 : The EPA thanks the commenter for this comment. Given the various terms used for glaze spraying in the Clay Ceramics manufacturing industry, the term “glaze spray operation” was used generically at proposal to refer to all types of glaze spray application when a requirement (such as emissions testing) a pplies to all types of glaze spraying, including tile glaze lines with glaze spraying and glaze spray booths such as sanitaryware manual glaze application, sanitaryware spray machine glaze application , and sanitaryware robot glaze application. A definition for “glaze spray operation” has be en added to the final rule to clarify the meaning of this term.

Comment 4 : Commenter 0244 noted that nowhere in the rule is non

- operating equipment addressed. The commenter asked whether, if a kiln is not operational duri ng the period of the required performance testing, it would need to be turned on just for performance testing. The commenter requested that non

- operational equipment not be restarted just to complete performance testing, and that performance testing be don e within 180 days of whenever the

20 79 FR 75704 and 75694 (Dec. 18, 2014) (proposed to be codified as Table 1 of 40 CFR Part 63, Subpart KKKKK).

21 Id . at 75704 (Dec . 18, 2014) (proposed to be codified as Table 1 of 40 CFR Part 63, Subpart KKKKK).

22 Id . at 75706 (Dec. 18, 2014) (proposed to be codified as Table 4 of 40 CFR Part 63, Subpart KKKKK).

23 Id . at 75704 (Dec. 18, 2014) (proposed to be codified as Table 1 of 4 0 CFR Part 63, Subpart KKKKK).79 equipment is next put into service. The commenter stated this approach is consistent with how this issue is addressed in the Boiler MACT rule (Subpart DDDDD).
Response 4 : The final rule does not require that an idled source be turned on just to perform a performance test. The G eneral P rovisions al ready cover the case where a source goes beyond the required date of the performance test because it is idle d (40 CFR 63.7(a)(4)) , and it is not necessary to spe cifically address or otherwise take any action on that issue in this rule. The G eneral P rovisions state that once the source is started up, performance testing is required to be completed within 180 days of starting up the source (40 CFR 63.7(a)(2) )

. Comme nt 5 : Commenter 0244 stated that average scrubber liquid flow rate and scrubber chemical feed rate should be deleted from Table 4 (i tem s 7.c and 8), as they are secondary parameters unnecessary for compliance determination. 24

Response 5 : The EPA disagrees w ith the commenter on one point. The EPA d isagrees that scrubber liquid flow rate is not an essential parameter. The p acked bed scrubbers installed on kilns to control acid gas emissions are designed to operate at a specific liquid

- to

- gas ratio to ensure ad equate gas

- to

- liquid contact in the scrubber. Maintaining adequate liquid flow in the scrubber is essential to scrubber performance. However, we do agree with the commenter that it is not necessary to monitor scrubber chemical feed rate . As long as the scrubber liquid pH is maintained at or above the level determined during the performance test, the chemical addition rate is simply not relevant. Scrubber pressure drop is also not a good indicator of performance for either PM or acid gases for this type o f scrubber. Therefore, we have modified the operating parameter requirements for this type of kiln to state that scrubber liquid pH and scrubber liquid flow rate must be monitored, and have removed the requirements to monitor chemical addition rate and scr ubber pressure drop. This revision has been made to both the clay ceramics and BSCP manufacturing rulemakings, since this issue is the same for both industries. Nonetheless

, r equests for approval of alternate monitoring procedure s to the Ad ministrator can be submitted according to the General Provisions under 40 CFR 63.8 (f)

. The EPA understand s that each facility may have different configuration s and different parameters for monitoring.

Comment 6 : Commenter 0244 noted that Table 6

, i tem 4.a requires a production rate limit be established for compliance with the HCl

- equivalent emission rate during the performance test . I f the performance test shows maximum potential HCl

- equivalent emissions from the facility do not have the potential to exceed the lim itation in Table 1, th en the commenter believed no throughput operating limit is needed and throughput monitoring is not required. The commenter requested EPA confirm th eir interpretation of the rule provision s is correct

. Response 6 : The EPA agrees with t he commenter. Clarifying language ha s be en added to the operating limit in Table 2 for the final rule.

Comment 7 : Commenter 0244 requested Table 6

, i tem 22 be revised because e ach batch processed in a shuttle kiln consists of a combination of products . S hu ttle kiln cycles are not developed on a “ per product ” basis, but time and temperature cycles are programmed and tracked for each batch. This condition should be reworded to remove reference to “ a designed firing time and temperature cycle for each product produced... ”

24 See Commenter 0244’s comments for Table 2, items 2.c and d.80 Response 7 : The EPA agrees with the commenter’s request and has revised Table 6 for the final rule accordingly. Similar text has also been revised in 40 CFR 63.8640(c)(7)(i)

- (ii), Table 3 and Table 7 for the final rule.

Comment 8 : Commenter 0244 asked how kiln compliance should be determined for the D/F concentration limit in Table 1

, Item 4.c if multiple stacks are tested. The commenter asked whether an air flow

- weighted average will need to be calculated to determine compliance w ith this limitation and recommended the rule specify how this should be done.
Response 8 : The A dministrator or delegated authority should be consulted if an alternative test plan is required for multiple stack testing

. . If an alte r native test method n eeds to be applied

, approval must be given by the Administrator according to the General Provisions under 40 CFR 63.7(c).

Comment 9 : Commenter 0244 made several requests for EPA to change process rate references in the rule from “ fired product ” to “ greenware, ” as this is the measure most often used for production rate tracking and how the commenter ’ s company specifically reported process rate data for the ICR test reports. The following specific changes were requested:

• 40 CFR 63.8595: How do I conduct performance tests and establish operating limits?: Several of the equations presented in this part reference process rate as “ fired product ” (i.e., Equation 1 variables “ MP ” and “ P ” ). These references should all be changed to

“ greenware product. ”

• Table 4: Item 4.a: This condition states that the operating limit for tunnel kiln process rate is based on HCl

- equivalent emissions testing. The requirement references equation 6, which identifies “ fired product ” for variable “ Capi. ” The commenter requested

“ greenware ” be identified for process weight monitoring, not fired product.

• Table 4: Item 5: This condition states the production rate must be on a fired

- product weight basis. The commenter requested greenware be used for process weight monitoring.

• Table 6: Item 4.a and a.i: The PM emission limit unit of measure should be tons of

“ greenware, ” not “ fired product. ”

• Table 6: Item 4.b and b.i: The Hg emission limit unit of measure should be tons of

“ greenware, ” not “ fired product. ”

• Tab le 6: Item 14: References to “ fired product ” should be changed to “ greenware, ” as previously discussed.

Response 9 : Because Equations 1 and 6 and Table 4: Item 5 are intended to apply to both sanitaryware and ceramic tile kilns, t he EPA cannot grant the commenter’s request to change “fired product” to “greenware product.” While the production rates reported by the sanitaryware
company in the ir section 114 survey response s are in terms of “greenware fired” into the kiln , the production rat es reported by the ceramic tile companies are in terms of “fired product” coming out of the kiln (as requested in the section 114 survey). However, we have changed the term “fired product” in Equations 1 and 6 and Table 4: Item 5 to the more generic term “ throughput” to eliminate any inconsistency with how the commenter’s company reported their production
rates. The EPA agree s with the commenter’s request to revise Table 6 : Items 4 and 14, which are specific to sanitaryware, and has made the revisions for t he final rule as suggested.81 Comment 1 0 : Commenter 0244 noted that several of the equations presented in 40 CFR 63.8595 (How do I conduct performance tests and establish operating limits?) reference process rate as

“ tons glaze sprayed ” (i.e., Equation 2 var iables “ MG ” and “ G ” ). These references should state the glaze application rate is the quantity of first fire glaze sprayed per hour on a dry basis. The commenter specifically reported process data as tons first

- fire glaze sprayed, on a dry basis, for the I CR test reports. The commenter also requested unit of measure for the PM emission limit be tons 1F glaze sprayed (dry basis) in Items 6

- 8 and 16

- 18 in Table 6.
Response 1 0 : The EPA agree s with the commenter’s request and ha s revised 40 CFR 63.8598 and Tabl e 6 for the final rule as suggested. Similar text has also been revised in Table 1 for the final rule.

Comment 1 1 : Commenter 0244 requested clarification from EPA about whether the term “ 3

- hour performance test ” used in Table 6 ( Items 4.a.ii, 4.b.ii, 4.c.ii, and 6

- 8) means three 1

- hour runs, asking if this was EPA ’ s intent based on 40 CFR 63.8595(e).
Response 1 1 : The EPA agrees with the commenter ’s interpretation of the term “3

- hour performance test

. ” The term is referring to the combination of three 1

- hour test runs.82 13.0 Continuous Compliance Requirements

Comment 1: Commenters 0244 and 0247 disagreed with the proposed monitoring requirements in 40 CFR 63.8600(a)(2). Commenter 0244 stated that the proposed requirement that the continuous monitoring sy stem ( CMS ) complete a minimum of one cycle of operation for each successive 15

- minute period does not align with how tunnel kilns operate, and is not applicable to tracking greenware throughput for a tunnel kiln. A new kiln car is typically pushed into a
t unnel kiln every 20

- 30 minutes. As proposed, this will result in many 15

- minute values being zero, which is not meaningful for determining hourly rates, or even 3

- hour block average rates (40 CFR 63.8600(a)(3)). It is standard kiln practice to document thr oughput on a daily basis, and so while an hourly push rate can be calculated, it is based on the daily throughput value, not on a collection of values recorded every 15

- minutes for one or two hours. As proposed, this monitoring requirement documenting tunn el kiln process rate s un workable. Commenter 0244 requested the hourly process rate be determined from the daily total throughput to more accurately account for the push rate schedule.

Commenter 0244 similarly objected to the requirement in 40 CFR 63.8615(b ) for continuous monitoring when the affected source is operating (except for periods of monitor malfunctions, associated repairs, and required QA or control activities). As explained above, continuous monitoring for tunnel kiln ware throughput cannot occu r in a manner that will allow reasonable hourly rates or 3

- hour block average rates to be determined . T he commenter requested hourly ware throughput values be determined from daily throughput monitoring.

C ommenter 0247 stated the EPA had no t provided a sat isfactory explanation in the docket for this unusually short averaging period. The commenter recommended the proposed monitoring requirements be replaced with daily, monthly and/or annual requirements consistent with existing state and federal air permit r equirements. Th e requirement as proposed provides no incremental compliance value, and is arbitrary and capricious.

Response 1: For parameter monitoring, the final rule uses a 3

- hour block average. EPA based the operating parameter 3

- hour block average on the estimated sampling time required to perform a three run performance test under this rule. However, the commenter appears to think that the requirements of the CMS 15

- minute measurements apply to throughput. This is not correct: the requirements apply t o continuously measured parameters, such as control device pressure drop.

Comment 2: Commenter 0247 challenged EPA ’ s proposal of semi

- annual calibration of the flow sensor in each liquid flow measurement device subject to the proposed NESHAP79 FR 75698 (co l. 2) ; proposed to be codified at 40 CFR 63.8600(b)(3)). The commenter recommended the semi

- annual calibration of flow sensors be replaced with a requirement to adher e to the sensor manufacturer ’ s written specifications and recommendations. The industry ha s adhered to flow sensor manufacturers ’ maintenance specifications and recommendations for at least a decade and their use was satisfactory to EPA and state agencies. EPA offered no reason why adherence to the manufacturer ’ s written specifications and reco mmendations should not be the approach taken in this NESHAP. The commenter noted the EPA proposed bag leak detection (BLD) systems be “ installed, operated, calibrated and maintained in accordance with the manufacturer ’ s written specifications and recommend ations ” ( 79 FR 75698 (col. 2

- 3) ; proposed83 codified at 40 CFR 63.8600(e)(l)). Since EPA allows this approach for BLD, it would be arbitrary and capricious for EPA to not take the same approach for flow sensors, or at least offer it as an alternative.

Commen ter 0247 stated that the EPA should be aware that calibration often requires removal of the sensor from service. Removal of these sensors for calibration purposes may result in a violation of one or more non

- NESHAP air quality requirements. The industry wi ll consider this routine maintenance of control equipment. EPA should not require c alibration of equipment that must be remov ed from service , unless calibration is specified by the manufacturer ’ s recommendations. The commenter concluded that the requiremen t as proposed is arbitrary and capricious.

Response 2: Semi

- annual calibrations of flow sensors ensure that the monitoring equipment are properly installed and maintained. EPA believes that, as finalized, the monitoring, recordkeeping, and reporting requir ements of the rule are the minimum necessary to determine continuous compliance. The requirements are generally consistent with the NESHAP general provisions and are reasonably consistent with other NESHAPs. The monitoring systems require periodic inspecti on, maintenance, and calibration to ensure continued accuracy. The EPA believes the proposed requirements for ensuring data quality and for site

- specific monitoring plans (where applicable) are reasonable and contends that the information required in the s ite

specific monitoring plans is necessary for regulators to ensure that the monitoring equipment are properly installed and maintained. The required information provides a written record of the calibration, maintenance, data quality, and recordkeeping and reporting procedures to be followed by the facility. EPA also notes that owners / operators can always seek approval for Operating Maintenance and Monitoring (OM&M) plan. The EPA intends that actions to deal with problems associated with monitor malfuncti on and instrument calibration for affected sources be addressed in the OM&M plan. The agency also believes that owners / operators can develop procedures in the OM&M plan to calibrate parameter measurements without causing safety or environmental release i ncidents.

Comment 3: Commenter 0247 challenged EPA ’ s proposed requirement for monthly inspections of electrical connections in pressure measurement devices subject to the proposed NESHAP ( 79 FR 75698 (col. 2) ; proposed codified at 40 CFR 63.8600(c)(7)). The commenter recommended the proposed monthly inspections be replaced with a requirement to follow the manufacturer ’ s written specifications and recommendations. The electrical department of a major source cera mic tile manufacturing facility routinely checks electrical connections in these devices according to manufacturer ’ s written specifications and recommendations and good electrical practices. Inspections, whether visible or mechanical, are recorded, and adj ustments made to equipment to the extent necessary. In practice, these electrical connections are not known to fail in large part because of integrity of the equipment and because these inspections are successful.

The commenter noted that EPA ’ s BLD proposa l relies on manufacturer ’ s written specifications and recommendations ( 79 FR 75698 (col. 2

- 3) ) . Since EPA allows this approach for BLD

, it would be arbitrary and capricious for EPA not to allow this approach or at least offer it as an alternative to the ce ramic tile industry . EPA offers no reason in the docket that adherence to the manufacturers ’ written specifications and recommendations and good electrical practices should84 not be the approach taken with respect to these electrical connections. The comment er concluded that EPA ’ s proposal is arbitrary and not supported by the docket.

Response 3: As stated by the commenter, the electrical department of a major source ceramic tile manufacturing facility responsibly and routinely checks electrical connections i n these devices according to manufacturer ’ s written specifications and recommendations and good electrical practices. Inspections, whether visible or mechanical, are recorded, and adjustments made to equipment to the extent necessary. EPA believes the mont hly inspections will ensure that the electrical connections in the pressure measurement devices are properly maintained.

Comment 4: Commenter 0247 challenged the proposed requirement for calibration of the pH meter in pH measurement devices subject to the proposed NESHAP once every eight (8) hours ( 79 FR 75698 (col. 2) ; proposed to be codified at 40 CFR 63.8600(d)(3)). The commenter recommended these proposed calibration requirements be replaced with a requirement to follow manufacturer ’ s written specificat ions and recommendations. T he industry already adheres to manufacturers ’ written specifications and recommendations , and have been satisfactory to EPA and state agencies. The commenter also noted EPA ’ s BLD proposal relies on manufacturer ’ s written specific ations and recommendations ( 79 FR 75698 (col. 2

- 3)). Since EPA allows this approach for BLD, it would be arbitrary and capricious for EPA to not allow this approach for the ceramic tile industry . EPA offered no reason why adherence to the manufacturer ’ s written specifications and recommendations should not be the approach taken for pH meters.

T he commenter stated the EPA should be aware that calibration often requires removal of the pH meter from service , which may result in a violation of one or more non

- NESHAP air quality requirements. The industry will consider calibration to be routine maintenance of control equipment. A ccording to the manufacturer ’ s written specifications and recommendations, comparison and not calibration assures continuous readings. Calibration should not be required, unless specified by the manufacturer ’ s written specifications and recommendations. The commenter concluded that the requirement as proposed is arbitrary and capricious.

Respon se 4: The pH meter check language has been modified to call for a one point calibration daily , and not a two point calibration every 8 hours of process operations

. The EPA believes that, as finalized, the monitoring, recordkeeping, and reporting requiremen ts of the rule are the minimum necessary to determine continuous compliance and are not overly burdensome. The requirements are generally consistent with the NESHAP general provisions and are reasonably consistent with other NESHAPs. The monitoring systems require periodic inspection, maintenance, and calibration to ensure continued accuracy. The EPA believes the proposed requirements for ensuring data quality and for OM&M plans (where applicable) are reasonable and contends that the information required in the site

- specific monitoring plans is necessary for regulators to ensure that the monitoring equipment are properly installed and maintained. The required information provides a written record of the calibration, maintenance, data quality, and recordkeepi ng and reporting procedures to be followed by the facility. The EPA also notes that owners / operators can always seek approval for site

- specific monitoring. This could include, as some commenters noted, requesting alternative calibration frequencies using consensus

- based approaches that can require fairly sophisticated analyses of past experience and failure rates. The
agency also believes that owners / operators can develop procedures to calibrate parameter measurements without causing safety or environme ntal release incidents.85 Comment 5 : Commenters 0244 and 0247 challenged EPA ’ s proposed requirement for semiannual calibration checks for temperature sensors ( 79 FR 75,622 at 75,699 ( col. 1) ; proposed to be codified at 40 CFR 63.8600(g)). Commenter 0247 argued no new temperature monitoring requirement should be imposed, provided the major source facility is capable of demonstrating through production monitoring equipment that the relevant tempe rature in any given unit is above 450 degrees C or below 200 degrees C

. The commenter stated this approach reflects the monitoring and testing requirements memo randum in EPA ’ s docket. 25 The C ommenter 0247 stated that the proposed regulation, if finalized wi th a temperature sensor requirement, would be arbitrary and capricious.

If EPA decides not to withdraw the proposed temperature sensor monitoring requirement, C ommenter 0247 noted that adherence to the manufacturer ’ s written specifications and recommendati ons is the best approach. The commenter noted that its members ’ actual experience with temperature monitoring equipment built in to the process equipment device in this industry has been excellent. It is among the most reliable of measurement devices it us es since it is critical to assure production quality. The industry adheres to temperature sensor manufacturer ’ s written specifications and recommendations for accuracy checks and/or replacement. Commenter 0244 also recommended that all sensor calibration c hecks should be based on the manufacturer ’ s recommendations, and asserted these checks should not arbitrarily be assigned a schedule of “ at least semiannually, ” as specified in 40 CFR 63.8600(g)(3). Commenter 0244 requested that this condition be revised a ccordingly.

Commenter 0244 challenged proposed 40 CFR 63.8600(g)(2) , stating a one percent or less temperature sensitivity bears no relationship to any emission standard in the proposed NESHAP. The commenter argued that the temperature measurement is irrel evant to D/F formation because

no new D/F is formed in the clay ceramics industry. EPA recommends that the monitoring equipment assure operations reflect these ranges, 26 not that the sensors have a one percent tolerance. A requirement that sensors irrelevan t to NESHAP maintain a narrow temperature tolerance is arbitrary and unnecessary to the NESHAP goal of continuous compliance.

Finally, Commenter 0247 commented that temperature sensors must be “ compared ” and not

“ calibrated

. ” Calibration typically requires removal of the device from service, per manufacturer specifications. During calibration, temperature measurements do not occur and hence calibration may result in a violation of one or more non

- NESHAP air quality requirements. For some sensors, calibratio n is not possible. For those sensors that are possible to calibrate, the industry will consider calibration to be routine maintenance of control equipment. However, the commenter argued that calibration should not be required, unless specified by the manuf acturer ’ s written specifications and recommendations. Commenter 0247 concluded the proposed calibration requirement is arbitrary and capricious.

25 Monitoring and Testing Requirements and Costs for Clay Ceramic NESHAP, at page 2 (Nov. 6, 2014). Docket Item No. EPA

- HQ

- OAR

- 2013

- 0290

- 0229.

26 Id

.86 Response 5 : Semi

- annual calibrations of temperature sensors ensure that the monitoring equipment are properly installed and maintained. The EPA disagrees that temperature is irrelevant to D/F formation. For further discussion on this issue, see Section 13.0 Continuous compliance Requirements Response 12

. The EPA believes that, as finalized, the monitoring, recordkeeping, and reporting requirements of the rule are the minimum necessary to determine continuous compliance and are not overly burdensome. The EP A agrees with the commenter that calibration is and sho uld be routine maintenance of the control device. The requirements are generally consistent with the NESHAP general provisions and are reasonably consistent with other NESHAPs. The monitoring systems require period ic inspection, maintenance, and calibration to ensure continued accuracy. The required information provides a written record of the calibration, maintenance, data quality, and recordkeeping and reporting procedures to be followed by the facility. The EPA a lso notes that owners /operators can always seek approval for site

- specific monitoring. This could include requesting alternative calibration frequencies using

consensus

- based approaches that can require fairly sophisticated analyses of past experience and failure rates. The Agency also believes that owners/operators can develop procedures to calibrate parameter measurements without causing safety or environmental release incidents.

Comment 6 : Commenters 0244 and 0247 challenged the operating limits in Table 2 proposed for kilns equipped with wet scrubbers. Commenter 0247 argued that packed bed wet scrubber technology manufacturers do not provide warranties for abate ment of PM emissions. It is designed to control HF, HCl, and other non

- HAP acid gases. P ropose d Table 2, items 2.a and 2.c state or imply that these wet scrubbers are expected to abate PM in PM performance tests ( 79 FR 75695 ; proposed to be codified as Table 2 of 40 CFR 63, Subpart KKKKK) ; t he commenter contended that they will not and that these p roposed requirements are inapplicable and must be removed. The commenter stated failure to do so would be arbitrary and capricious.

Commenter 0244 requested that items 2c (scrubber liquid flow rate) and 2d ( scrubber chemical feed rate) be removed from Tabl e 2 and items 2.a.iii (scrubber liquid flow rate) and 2.a.iv (scrubber chemical feed rate) be removed from Table 7 because they add no value for compliance assurance. The commenter noted these two items are secondary parameters to the parameters the scrubber pressure drop and scrubber liquid pH and that any deviation is immediately detected by monitoring pressure drop and pH

. O nly the pressure drop and pH are needed to assure proper operation of the scrubber. Also, there are some scrubber designs (i.e

., orifice plate scrubber) that do not actively circulate scrubber liquid and so item 2c in Table 2 and item 2.a.iv in Table 7 are not universally applicable.

Response 6: The E PA disagrees with the comment er s on two points. First, the manufacturers’

warran ties concerning PM removal are not relevant. Though packed bed scrubbers are primarily designed to remove acid gases, some PM removal would be expected to occur. Therefore,

e nsuring the scrubber is performing at the level demonstrated during the compliance test is important from the perspective of both PM and acid gas removal. The EPA also disagrees that liquid flow rate is not an essential parameter. Packed bed scrubbers are designed to operate at a specific liquid

- to

- gas ratio to e nsure adequate gas

- to

- li quid contact in the scrubber. Maintaining adequate liquid flow in the scrubber is essential to scrubber performance. However, we do agree with the commenter s that it is not necessary to monitor all four parameters. It is the scrubber pH that drives the aci d gas removal rate. As long as the pH is maintained at or above the level determined during the performance test, the chemical addition rate is simply not relevant.87 Scrubber pressure drop is not a good indicator of performance for either PM or acid gases f or this type of scrubber. Therefore, we have modified the operating parameters requirements to state that pH and liquid flow rate must be monitored, and have removed the requirements to monitor chemical addition rate and scrubber pressure drop . This revisi on has been made to both the clay ceramics and BSCP manufacturing rulemakings, since this issue is the same for both industries.

Comment 7 : Commenter 0247 accept ed the following parameters for continuous monitoring in relation to the manufacturer ’ s written specifications, as applicable to sources subject to a final NESHAP:

1. Pressure drop 2. Dry sorbent feed rate 3. Scrubber recirculation water flow rate 4. Scrubber recirculation water pH 5. Kiln firing temperature 6. Tile dryer temperature 7. Hours of routine control device maintenance 8. Method 22 and 9 observations/measurements, if required to be performed.

Response 7 : The EPA ha s outlined in the final rule what parameters are necessary to ensure proper operations of the process and control devices and to ensure continuing com pliance with emission standards. If specific monitoring parameters do not correlate to the site specific control devices, the delegated authority can be petitioned for alternative monitoring options.

Comment 8 : Commenters 0244 and 0247 objected to EPA ’ s pr oposed approach in 40 CFR 63.8620(e) to include visible emissions (VE) observations as a continuous compliance option ( 79 FR 75699 (col. 3) ) and recommended the VE requirement be deleted

. C ommenter 0247 noted that spray dryers, tile dryers, glaze spray ope rations and kilns are subject to VE and/or PM emissions limits established in state air permits and regulations. EPA ’ s proposal to establish a VE requirement for exhaust gases composed of both non

- HAP particulate and possibly HAP particulate is technically infeasible and beyond EPA ’ s CAA section 112(d) authority. The commenter noted that EPA ’ s records indicate the percentage of HAP in the overall kiln particulate loading ranges from a high of 3 percent to a low of 0.5 percent. The commenter asserted the EPA does not have the authority to regulate the other 97

- 99.5 percent that is non

HAP particulate and therefore, the propos ed VE requirement is unlawful

, arbitrary and capricious

.

C ommenter 0247 further argued the proposed VE requirement would be inconsistent and possibly conflict with state VE requirements. The commenter noted s tate VE requirements are sufficiently stringent and it would be arbitrary and capricious for a final NESHAP to negate or supersede VE limitations in state permit s on the basis that a very small fraction of the PM resulting in VE might be a HAP. The commenter argued that NESHAP compliance should be deemed achieved if a source is in compliance with its state air permit.

Commenter 0244 argued the EPA’s data show a PM emission rate of approximately 0.2 lb /hr and noted that t here are no visible emissions associated with this magnitude of emissions. There are88 only a few reasons that may lead to increased VE from a tunnel kiln (i.e., malfunction of the combustion gas trai n, kiln car malfunction (wreck)), and none are associated with increased metal HAP emissions. The commenter stated that n one of these occurrences correlate with HAP emissions from the ware, and each occurrence will be readily detectable by process operator s before any daily VE reading is made. The commenter further noted that all of their first

- fire tunnel kilns are natural gas

- fired (propane as backup) and that t here are no active processing of materials in kilns. Sprayed greenware is placed on kiln cars a nd the kiln cars transported from the kiln entrance to the kiln exit

. This process does not generate any significant particulate emissions. The commenter stated that k iln temperature monitoring is sufficient to document compliance and is also consistent wi th the monitoring required under the Clay MACT area source rule ( s ubpart RRRRRR). The commenter stated the VE requirement should be deleted as it is costly to conduct, does not add to compliance assurance, and is unnecessary because the kiln temperature mo nitoring is sufficient to demonstrate kiln performance and process control.

Commenter 0244 also noted that most tunnel kilns have two or three cooling exhaust stacks, in addition to the primary exhaust stack (POC

- products of combustion). The commenter st ated that daily VE readings at c ooling exhausts should not be required because these stacks have no VE under any circumstance. The commenter further noted that t est data show PM emissions from tunnel kiln POC stacks are very low and the stack exhaust conta ins no VE. The commenter also argued that t est data has not show n increased VE are related to increased HAP emissions.

Response 8 : As noted by C ommenter 0244

, there are only a few reasons that may lead to increased VE from a tunnel kiln (i.e., malfunction of the combustion gas train, kiln car malfunction (wreck). If VE are seen, it is an indicator that there is an issue with the process and the process needs to be inspected and fixed. There are daily visual emission readings required in
t he Clay MACT area source rule (s ubpart RRRRRR)

. Also the rule does not require VE readings at cooling exhaust stacks, but rather only at kiln exhaust stacks.

Comment 9 : Commente r 0247 proposed two alternatives to EPA ’ s proposed daily Method 22 VE observations

, fabric filter pressure drop and Method 9 opacity measurements.

In the first alternative, Commenter 0247 proposed daily reading and recording of fabric filter pressure drop using a magnahelic gauge or other equivalent pressure measurement device as an alternative. The magnahelic gauge or other equivalent pressure measurement devices are objective and have a long

- standing record in the industry of quality and accuracy, in cont rast to the VE observations that are subjectiv e

. Pressure gauges have been specified, preferred by, and satisfactory to EPA and delegated states in other contexts where VE observation was an alternative. The commenter argued the re is no basis for EPA to no t, at a minimum, add pressure gauges as an alternative option.

In the second alternative, C ommenter 0247 recommended sources have the option, but not the obligation

, to conduct Method 9 opacity measurements for the stack or stacks in geographic/operational proximity to a Method 22 noncompliant observation or non

- compliant magnahelic measurement and to base their compliance determination and title V deviation reporting on the results of the Method 9 measurement. T he commenter asserted 40 CFR 63.8620(e)(3) is inconsistent with Title V and state air permit provisions and the changes the commenter recommended would be more consistent with the title V program . The commenter89 stated there is nothing in the docket at odds with their recommendation and failure to ado pt it would be arbitrary and capricious.

Response 9 : The EPA thanks the commenter for their comments. The fabric filter pressure drop is not an effective means by which to detect changes in performance of a fabric filter relative to compliance. The BLD systems alert the operator or owne r of an issue in the baghouse. Pressure drop is not an early indicator of continued compliance. O nce the pressure drop is seen, the system could very well be out of compliance.
The operating limit for o pacity is no visual emissions. Method 22 is the appropriate method for application because it is a yes/no reading and does not give a quantifiable reading like Method 9. It should be noted that VE is merely a tool to gauge whether the system is working properly and the remedy for a VE failure is to take corrective action. If no VE is observed, then no action is warranted.

Comment 10 : Commenters 0244 and 0247 opposed the 15

- minute Method 22 observation requirement. The commenters noted that Section 11.4.2 of Method 22 specifies a 6

- minute observation, while proposed 40 CFR 63.8620(e)(l) requires a 15

- minute observation. Commenter 0247 stated there is no explanation or justification provided for the difference and argued that

a 15

- minute observation period is arbitrary and capric ious.

Commenter 0247 stated that the proposed 15

- minute VE observation period would require them to hire more than one full time employee whose only job would be to perform VE observations. Major sources in this subcategory have one or more than one manufa cturing building

, several hundred yards in length or width, or both, multiple factories or other configurations, and multiple emission points all on one contiguous property. The commenter claimed that EPA either did not understand or ignored these proporti ons because its economic impact analysis is inaccurate. Compliance with this VE proposal would take all day, every day. T he annual estimated cost for the proposed VE measurements of $2,984 27 is unrealistic. Industry representatives estimate the actual cost with benefits to comply with this proposal would be 15

- 30 times more than this estimate. Even a reduction in observation time to 6 minutes, or the weekly observation frequency that is proposed compliant VE observations, 28 are more than is necessary to assur e NESHAP compliance.

Commenter s 0244 and 0247 recommended daily magnahelic gauging of pressure drop should be added as an alternative to VE observations. If EPA keeps the VE requirements , the n the
commenter recommended 6

- minute Method 22 observations as th ey will yield the same compliance determinations as the 15 minute observations at lower cost. The commenter further proposed that NESHAP VE observations be required to satisfy state permit requirements and not a separate NESHAP

- imposed requirement. Requiri ng VE for longer than 6 minutes serves no lawful purpose, is unduly burdensome, and is unnecessary. If finalized as proposed, C ommenter 0247 stated this proposal would be arbitrary and capricious.

27 Docket Item N o. EPA

- HQ

- OAR

- 2013

- 0290

- 0229, at Tables 1 and 4 (Nov. 6, 2014).

28 40 CFR 63.8620(e)(2) and (3), 79 FR 75699 (col. 3) (Dec. 18, 2014)90 Response 10 : Method 22 does not specify 6 minute observations. It leaves the observation period up to the subpart. According to the Method

, n o observation may be less than 6 minutes and observers must take a break after 15

- 20 minutes. Many su bparts designate 1 to 2 hou rs of observations. A 15

- minute period allows for only one observer and is consistent with the 15

- minute requirement for collecting the CMS data

. In addition the cost for daily VE is for the kiln stack only and thus shou l d not be more than 15 minutes per day per stack. Unless there are 32 kiln stacks per contiguous source in operation in any one 8

- hour shift , the need for a full time reader of VE is not substantiated.

Comment 11 : Commenter 0244 noted that Table 2

, Item 5.c requires the kiln operating tempe rature to be maintained at or below the average temperature established during the dioxin/furan performance test. The commenter stated this condition seems contrary to Item 4 of this table, which states that kiln temperature should be at or above the average temperature established during the dioxin/furan performance test. Commenter 0244 requested EPA confirm how this operating limit will be applied.
Response 11 : T he EPA agrees with the commenter that there is a discrepancy. Item 5.c should have stated that sources must maintain the operating temperature at or “ above ” the average temperature established during the D/F performance test. Regardless, as noted in our re sponse to the following comment, we are revising the operating limit for promulgation to require sources
to m aintain the stack temperature and not the kiln temperature, at or below the highest 4

- hour average stack temperature established during the D/F per formance test

. Comment 12 : Commenters 0244 and 0247 expressed concern about the kiln temperature requirement s in Table 2

, i tem 5.c . and Table 7, 5.a.iii. Commenter 0244 asserted that the operating temperature limit needs to be established at a level that affords some operational flexibility 29 and requested the temperature limitation be revised to either: (1) the peak kiln temperature must be maintained above 2000 degrees F ; or (2) set at least 100 degrees F below the average temperature achieved in the perf ormance test. Noting that a tunnel kiln is comprised of many different temperature zones across the ramp

- up, soak, and rapid cool temperature profile of the tunnel kiln, the commenter also requested that EPA specify exactly what temperature is to be used f or monitoring for the operating limit.

Commenter 0247 stated that there is no justification for a CPMS

- specific temperature measurement requirement so long as the major source facility is capable of demonstrating through production monitoring equipment tha t the relevant temperature is above 450 degrees C for kilns and below 200 degrees C for tile dryers. The commenter stated EPA ’ s CPMS proposal is unnecessary, unduly burdensome

, does not result in incremental protection of air quality , and would be arbitrar y and capricious.

Commenter 0247 also challenged EPA ’ s proposal to require D/F CPMS as proposed in 40 CFR 63.8570. The commenter argued the EPA has no technical foundation for D/F CPMS because there are no scientifically valid D/F emissions information for this subcategory and no available D/F

- specific CPMS technology.

29 Assuming EPA’s intent is to limit the minimum operating temperature of a kiln to at or above the average temperature esta blished during the dioxin/furan performance test.91 The commenter requested clarification that CPMS applies only to the air pollution control equipment employed during NESHAP compliance performance testing and that CPMS does not apply to e quipment or air pollutants not subject to this NESHAP. The commenter also stated EPA failed to provide the public with adequate detail regarding the extent of the proposed CPMS. 30 EPA ’ s failure unlawfully precludes the public ’ s opportunity to comment fully. It would be arbitrary and capricious for EPA to finalize detailed CPMS regulations without proposing such details and provid ing an opportunity for the public to comment.

F ederal laws and Executive Orders 12866 and 13563 require EPA to consider the requir ements of other EPA programs in establishing NESHAP monitoring system requirements to assure a lack of duplication and overlap. Those facilities in this industry subject to Part 70 or 71 Title V permitting must comply with CAM requirements, which are exten sive. EPA failed to consider CAM or to explain why compliance with CAM requirements is not legally and technically adequate to demonstrate continuous compliance with a final NESHAP. The commenter argued there is no justification for a CPMS program where, a s here, other already

- applicable requirements achieve the same outcome.

Response 12 : We agree with the commenter that redoing performance tests based on variations in kiln temperatures is not an efficient use of resources when the small kiln temperature

va riations most likely do not have an effect on the dioxin emissions level. The better parameter for demonstrating compliance would be the stack temperature. Dioxins and Furans are known to form in post

- combustion gases in temperature ranges of 200 to 400 d egrees C (392 to 752 degrees F)

. 31 A ssuring that the maximum stack temperature recorded during the compliance test is never exceeded will assure that the dioxin limit is continuously met. Therefore, we are revising the requirement by basing the performance parameter on the stack temperature and not the kiln temperature. Thus, the new requirements in Table 2 to Subpart KKKKK of Part 63

-- Operating Limits, and Table 4 to Subpart KKKKK of Part 63

-- Requirements for Performance Tests, will read as follows:

You mu st continuously measure the stack temperature and determine and record the temperature values for the three test runs. The highest 4

- hour average stack temperature of the three test runs establishes your maximum site

- specific stack temperature operating li mit.

The EPA disagrees with the comment that “ EPA has no technical foundation for proposing or imposing CPMS for D/F unless and until scientifically valid D/F emissions information is presented that demonstrates significant D/F emissions from this subcateg ory. ” Valid D/F emissions were presented in the ICR and represented levels that a MACT limit was set. Because the performance tests are required, a CPMS is needed to demonstrate the system is working in a similar mann er that demonstrated compliance with th e D/F limit. If an owner or operator have a different parameter t hey use to monitor the system and emission, he/she can su bmit an

30 79 FR 75695 and 75698 (Dec. 18, 2014)(proposed to be codified at 40 CFR 63.8575 and 63.8600).

31 Observations on the Effects of Process Parameters on Dioxin/Furan Yield in Municipal Waste and Coal Systems, Gullett, Brian K. and Raghunathan K., Chemosphere, Vol

. 34 Nos

. 5

- 7, p. 1027, 1997

.92 application to use of an altern ative monitoring procedure by following the G en er al P rovisions section 63.8 ( f ) ( 4).

Comment 13 : Commenter 0244 requested that EPA revise Table 2

, Item 8 and Table 7

, Item 8.a to change the frequency of leak inspections for system ductwork and control device equipment. The proposed requirement to conduct “ weekly ” visual inspections is more frequent t han necessary for compliance assurance. A weekly inspection is unnecessarily burdensome for equipment that is not prone to leaks, where any leaks would develop slowly, and even if a leak at a water curtain spray booth were to occur, it would not result in added emissions to the atmosphere or a violation of an emission limitation. The commenter requested the frequency of the proposed inspection be revised to no more than once/year.
Response 13 : This visual inspection is to ensure the process and control devi ce is working properly and there are no glaring issues with the process. It is common practice to have a walk through before shift change in many industry sectors. This visual check should be easily incorporated in daily operations.

Comment 14 : Commenter 0 244 stated that more information is needed on how redoing performance tests to set new operating limits can be completed without violating the MACT/permit (see Table 7: Item 5.a.iii). For instance, if 6 months after the initial performance test, the source operator wants to make process improvements that may decrease the peak operating temperature of the kiln by 100 degrees F from that measured during the first performance, the operator must redo the performance test at the lower temperature. It can take

se veral weeks to optimize a new throughput cycle, and while this is being done, the kiln will be in constant noncompliance (below the average temperature measured during the previous performance test) as it migrates to the new process curve. The commenter as ked how this situation should be handled. The commenter requested that an appropriate temperature limit is to maintain the peak kiln temperature above 2000 degrees F as previously discussed, for continuous compliance demonstration. Alternatively, the comme nter requested some type of temporary waiver be available for a source so that when kiln cycle changes are implemented they do not result in non

- compliance with the rule

. Response 14 : We have revised the requirement for continuous compliance in Table 7, it em 5.a.iii. so that the owner or operator must maintain stack temperatures, and not kiln temperatures, to assure continuous compliance with the D/F limit. We believe this new requirement will assure D/F does not reform and is a better parameter for which to assure compliance. The revised requirement reads as follows:

Collecting the stack temperature data according to §63.8600(a); and maintaining the stack
t emperature at or below the highest stack temperature established during the dioxin/furan performance test in which compliance was demonstrated.

Please refer to Comment 12, Response 12 for more background on this revision.

Comment 15 : Commenter 0244 stated that the two conditions in Table 7

, i tem s 12.a.ii and iii for making an alternative fuel notification within 48 hours of a declaration of a natural gas curtailment event and submitting a written report of alternative fuel use within 10 days of93 terminating alternative fuel use are inappropriate and unnecessary. Alternative fuel use during periods of natural gas curtailment is already an approved operating scenario in air permits. These instances are already required to be addressed in the facility ’ s semi

- ann ual monitoring report, even though they technically do not constitute a permit deviation. This is sufficient notification for this type of activity, and special 48

- hour notification and 10

- day reporting for non

- deviation activity serves no useful purpose. Commenter 0244 requested these two requirements be removed and that EPA also confirm that similar requirements do not apply to tunnel kilns.
Response 15 : The EPA disagrees with the commenter’s request to remove the 48

- hour notification of alternative fuel use and the 10

- working day report of terminating alternative fuel use. The commenter argues that the notification and report are unnecessary and that using an alternative fuel is not considered a deviation. However, failure to give EPA timely notice that t he facility is no longer complying with the work practice standard requiring natural gas usage would be considered a violation of the standard. Providing notice to EPA in a semiannual monitoring report could mean that the facility is operating as long as 6 months in a manner inconsistent with the work practice standard. Timely notice is essential to ensure that the facility remains in compliance with the standard. We believe that a 48

- hour notification of alternative fuel use and 10

- working day report of te rminating alternative fuel use provide timely notice to EPA without imposing an undue burden on the facility. Regarding the commenter’s other request that EPA also confirm that similar requirements do not apply to tunnel kilns , the regulatory language clea rly references the periodic kiln work practice standard in Table 3 to the subpart, so no further clarification is necessary.

Comment 16 : Commenter 0244 requested clarification concerning the impact of power outages on compliance. The commenter noted that it is not uncommon for power outages to affect a facility, and so affect tunnel kiln operation by shutting down the natural gas fuel train. It can take a few hours to get kilns relit and operating . A s a result, the kiln temperature can drop a few hund red degrees in response to the outage and may fall below the operating limit for temperature. The commenter asked whether such a power outage event will be classified as a noncompliance event or a deviation. The commenter stated that issues with electrical grid reliability are out side their company ’ s control.
Response 16 : A power outage that results in “sudden, infrequent, not reasonably preventable failures of emissions control, process or monitoring equipment, ” such as a tunnel kiln, would, by definition, fall into the category of a malfunction ( 40 CFR 63.2)

. In the event that a source fails to comply with the applicable CAA section 112 standards as a result of a malfunction event, the EPA would determine an appropriate response based on, among other thing s, the good faith 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.94 14.0 Compliance Dates

Comment 1: Commenters 0246 and 0247 supported the compliance deadlines proposed in 40 CFR 63.8545, 79 FR 75694 (col. 2), which they stated are consistent with CAA section 112(i)(3), and 40 CFR 63.6(c)(5) and 63.6(b)(7).
Response 1: The EPA appreciates the comme nt ers ’ support for the compliance deadlines

.95 15.0 Recordkeeping and Reporting

Comment 1: Commenter 0244 requested EPA change the performance test notification in 40 CFR 63.8630(d) from 60 to 30 days. The commenter asserted that 30 days is sufficient for notification for a performance test. It is common for state agencies to only require 30

- day notice for emissions testing, and this condition should be consistent with state requirements. Th e State of Wisconsin only requires a 20

- day notification of intent to test [NR439.07(2)].

Commenter 0244 also requested that the performance test reporting and Notification of Compliance Status submittals in 40 CFR 63.8630(e)(1) and 40 CFR 63.8635(i) be ch anged from 60 to 120 days. The commenter asserted that 120 days is needed for reporting due to the magnitude and complexity of the testing and analysis being required, and to account for documented ERT tool use issues. The commenter contended that 60 days is an unreasonably short amount of time to report results, as acknowledged by EPA in Section V of the September 9, 2014 memo randum from EPA to the docket titled “ Use of the Upper Prediction Limit for Calculating MACT Floors, ” which specifically refers to t he collection of HAP emissions data as

a “ ...time

- and resource

- intensive effort, as emissions tests can take more than a week to perform, analyses of samples from the tests can take more than a month, preparation of test reports typically takes several mo nths, and costs range up to $40,000 per test per pollutant. ”

Response 1 : State and local agencies have varying requirements depending on the permit. The 60 days required for the performance test notification and notification of compliance status is the fe deral requirement for part 63 in the G eneral P rovisions when states do not have delegation. In 40 CFR 63.9(i) of the General Provisions

, the A dministrator can be petitioned for an adjustment to the notification deadline and can approve or deny the request for an adjustment.

Comment 2 : Commenter 0244 requested EPA delete the alternative fuel notification in 40 CFR 63.8630(g) and the alternative fuel use report in 40 CFR 63.8635(h) . The requirement s to submit a notification of alternative fuel use within 48 h ours of a period of natural gas curtailment and submit a written report of alternative fuel use within 10 days of terminating alternative fuel use

are unnecessary. Alternative fuel use during such periods is already an approved operating scenario in air pe rmits. These instances are already required to be addressed in the facility ’ s semi

- annual monitoring report, even though they technically do not constitute a permit deviation. This is sufficient notification for this type of activity, and special 48

- hour n otification and 10

- day reporting for non

- deviation activity serves no useful purpose and is an undue burden.
Response 2 : The EPA disagrees with the commenter’s request to remove the 48

- hour notification of alternative fuel use and the 10

- working day report of terminating alternative fuel use. The commenter argues that the notification and report are unnecessary and that using an alternative fuel is not considered a deviation. However, failure to give EPA timely notice that the facility is no longer complyin g with the work practice standard requiring natural gas usage would be considered a violation of the standard. Providing notice to EPA in a semiannual monitoring report could mean that the facility is operating as long as 6 months in a manner inconsistent with the work practice standard. Timely notice is essential to ensure that the facility remains in compliance with the standard. We believe that a 48

- hour notification of alternative fuel use and 10

- working day report of terminating alternative fuel use pr ovide timely notice to EPA without imposing an undue burden on the facility.96 Comment 3 : Commenter 0244 requested EPA revise the provisions in 40 CFR 63.8640(c)(3) to require all kiln throughput data be reported on a “ ton greenware processed ” basis, rather than on

a “ fired

- product weight ” basis. ICR testing production data were greenware

- based, not fired product

- based . T his record should be based on greenware weight since th is is consistent with how process data was reported to EPA for the ICR.
Response 3 : B ecause the recordkeeping requirement in 40 CFR 63.8640(c)(3) is intended to apply to both sanitaryware and ceramic tile kilns, the EPA cannot grant the commenter’s request to change “fired

- product weight ” to “ ton greenware pro cessed .” As noted previously i n this document, w hile the production rates reported by the sanitaryware company in their section 114 survey responses are in terms of “greenware fired” into the kiln, the production rates reported by the ceramic tile companies are in terms of “fired produ ct” coming out of the kiln (as requested in the section 114 survey). However, we have changed the term “fired

- product weight ” in 40 CFR 63.8640(c)(3) to the more generic term “ ton throughput processed ” to eliminate any inconsistency with how the commenter’ s company reported their production rates.97 16.0 Submission of Emission Test Results (ERT)

Comment 1: Commenter 0247 opposed the proposed use of EPA ’ s ERT for reporting data from the ceramic tile subcategory. According to the commenter, EPA ’ s ERT software is a

“ bureaucratic disaster, acknowledged as such by EPA and the regulated community. ” The commenter noted that the March 2010 ICR required the ceramic tile industry to submit stack testing information to EPA through the ERT. The industry ha s no objection to the use of electronic submissions that are usable and quality assured. However, the commenter ’ s consultants, who had prior experience with the ERT, experienced problems enter ing data into ERT

. C orrectly entered data was randomly changed o r deleted by the software and data was inaccurately converted by the ERT from one draft to the next. Breakdowns and errors in the software were observed and the ultimate ly EPA went back to the stack testing reports themselves for reliable data, and maybe t o verify and correct ERT

- reported data. Under these circumstances, the commenter objected to EPA ’ s proposal to continue to require the industry to submit future data using the ERT. The commenter proposed that EPA delete the requirement to submit data using the ERT and instead only require the underlying stack testing report to be submitted.
Response 1: The EPA disagrees with the commenter that the EPA delete the requirement to submit data using the ERT. The ERT has continually improved over the past 5 years based on comments from users. It is currently required in over two dozen federal rules and the EPA has currently proposed to require its use in the majority of NSPS rules. States are well aware of the ERT and some states are requiring its use for state te sting as well as federal testing. Some states allow ERT reports instead of hard copies. The ERT equations have be validated and if the data is entered correctly, the final results are accurate and reliable. Over 500 test reports have been submitted via ERT

. The ERT has a c ompleten ess c heck to assist users in completing the ERT file. Users will still need to review their data and make sure the ERT data was entered correctly.

The ERT is designed to streamline, standardize, and incorporate quality assurance an d quality control information for all the test reports and facilitate their submittal to th e EPA. The ERT will also make the process of developing emissions factors much more transparent. All the steps taken and data used to develop emissions factors will be much clearer with our new system. We understand that there will be little or no reduction in the effort needed to produce the test report initially, but as users gain expertise with the system and it improves over time, the time, resources, and consiste ncy for review and evaluation will be improved.98 17.0 Definitions

Comment 1: Commenter 0244 stated that the definition for “ Kiln design capacity ” in 40 CFR 63.8665 should be revised to state “ maximum amount of greenware clay ceramics. ”
Response 1: The EPA cannot grant the commenter’s request

, because this definition is intended to apply to both sanitaryware and ceramic tile. As noted previously in this document, w hile the production rates reported by the sanitaryware company in the ir section 114 survey res ponse s are in terms of “greenware fired” into the kiln , the production rates reported by the ceramic tile companies are in terms of “fired product” coming out of the kiln (as requested in the section 114 survey). Consequently, we will continue using the mo re generic term “clay ceramics” in this def inition.

Comment 2: Commenter 0244 recommended the definition for “ Particulate matter (PM) ” in 40 CFR 63.8665 be revised to state “ ...emission of filterable PM... ” The commenter stated this change would confirm th at Reference Method 5 front

- half applies and would be consistent with the wording used in Section II of the November 6, 2014 memo randum from RTI International to EPA titled “ MACT Floor Analysis for Clay Ceramics. ”
Response 2: The EPA agree s with the commen ter’s request and ha s revised the definition of “Particulate matter (PM)” in 40 CFR 8655 as suggested. In response to another comment (in section 7.2 of this document) , the EPA has also removed mention of Hg from the definition, since Hg is being regulated separately, and PM is intended to serve as a surrogate for non

- Hg metal HAP.99 18.0 Costs and Impacts

Comment 1: Commenter 0244 argued that EPA has significantly underestimated emissions testing costs in preamble section I.A.2, Table 2 ($102,000, which i s $24,900 annualized cost). The commenter ’ s actual cost for emissions testing in 2010 per EPA ’ s ICR exceeded $320,000 at their three facilities. As this proposed rule is currently drafted, the scope for performance testing will include more stacks than com pleted under the ICR, and when testing is required in 2019, costs will likely exceed $400,000, and potentially much higher if performance test adjustments are needed to meet variable process conditions, including market demand. This is significantly higher than EPA ’ s estimate, and is based on actual costs incurred in 2010 at the commenter ’ s three facilities. The commenter stated the EPA should revise the cost estimate. Commenter 0244 argued that the costs in Table 5 of the November 6, 2014 memo randum from R TI International (Holloway) to EPA (Telander) titled “ Monitoring and Testing Requirements and Costs for the Clay Ceramics NESHAP ” are also underestimated and T able 5 needs to be redone with real cost data to make this a valid assessment.
Response 1: Testin g costs for both BSCP and Clay Ceramics have been revised to include costs for audits ($1000), ERT ($2000) and Compliance and Emissions Data Reporting Interface ( CEDRI ) ($2000), based on information provided by Commenter EPA

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- 0539 on the pr oposed BSCP rule. The inclusion of these costs (50 percent of which was assumed to apply to each individual test) is estimated to increase testing costs close to Commenter 0244’s estimate. We are unable to use the commenter’s total estimates, because our t esting cost estimates are developed on a more specific basis, based on the number of sources tested, the test methods used, and costs for equipment rental, travel, testing, laboratory analysis, test report, and the additional three items noted above.100 19 .0 Statutory and Executive Order reviews

Comment 1: Commenter 0247 argued that the proposed NESHAP is invalid because EPA failed to comply with the Regulatory Flexibility Act (RFA) and SBREFA and that ignoring small business interests and impacts in the ce ramic tile manufacturing industry violated the RFA and the SBREFA. The cost of major source compliance with the proposed NESHAP would be an economic barrier to the expansion of small businesses and will provide non

- market

- based economic advantages to foreign producers importing their products into the U.S . Financing of capital projects will be more expensive and difficult and small businesses will bear a disproportionate burden

. The EPA ’ s economic analysis was based on three existing major sources in t his subcategory and is flawed.

The commenter noted that the RFA and SBREFA require the EPA to consider the impact of a proposed regulation on small business and to adjust its regulatory approach when necessary. On a per capita basis, the commenter argued, the vast majority of the ceramic tile industry in the United States is comprised of small businesses that fall under the small business size standards of the U.S. Small Business Administration, 13 CFR 121.201 (2014). Together, they make up a

“ substantial ” portion of the industry ; however, the EPA recognized 12 small businesses in this subcategory in 2003 for the vacated 2003 NESHAP for this subcategory, 32 but ignored economic impacts on small business for this rulemaking . The commenter stated that the indust ry has changed markedly since 2003 and hence the 2003 analysis is inadequate support for this rulemaking

. According to the commenter, EPA ’ s failure to accurately evaluate the industry deprived small ceramic tile manufacturing businesses of their RFA and SB REFA rights, including their right to a Small Business Advocacy Review (SBAR) panel.

The commenter argued that RFA and SBREFA also require EPA to consider whether the possible future sources subject to the NESHAP might be small businesses. The commenter s tated that EPA cannot lawfully promulgate a final NESHAP unless it consider s the needs of small business by follow ing the requirements of the RFA and the SBREFA.

Response 1: The EPA disagrees with the commenter that we failed to comply with the RFA and SBREFA. Under the RFA, the EPA is required to determine whether the NESHAP will have a significant economic impact on a substantial number of small entities, in which case the EPA would have to take action under the RFA and SBREFA to minimize the impacts. Because there are currently no major source ceramic tile manufacturing facilities that would be subject to the NESHAP, there is no economic impact to evaluate, and no action to be taken under the RFA and SBREFA.

Comment 2: Commenter 0247 argued the propose d NESHAP was issued in violation of the Information Quality Act (IQA) and the Paperwork Reduction Act (PRA) , as amended

. According to the commenter, the re is no evidence th e EPA considered and discharged its IQA or PRA obligations in the development of the proposed NESHAP. T he commenter alleged the March 2010 ICR violated the PRA because it required stack testing using a method “ known by EPA to not generate scientifically valid data useable for purposes of development of the NESHAP. ”

32 Economic Analysis of the Clay Ceramics Manufacturing NESHAP: Final Rule, EPA

- 452/R

- 03

- 007, at pages 5

- 1 and 5

- 2, and Table A, EPA Office of Air Quality Planning and Sta ndards (Feb. 2003).101 The commenter noted th e PRA allows the Office of Management and Budget ( OMB ) to approve an information collection request only if it has first determined the data collection is necessary and has “ practical utility. ” See, e.g., 44 U.S.C. 3508 (2014). It is EPA ’ s legal burden to demonstrate to OMB that the data is seeks to collect through an ICR meets this burden. 5 CFR 1320.9 (2014). According to OMB ’ s implementing regulations, the term “ practical utility ”

means: “ the actual, not merely the theoretical or potential, usefulness of information to or for an agency, taking into account its accuracy, validity, adequacy, and reliability, and the agency ’ s ability to process the information it collects (or a person ’ s ability to receive and process that which is disclosed, in the case of a third

- party or public disclosure) in a useful and timely fashion. ” 5 CFR 1320.3(1) (2014). The commenter alleged that the EPA knew at the time it sought OMB approval for the March 2010 ICR that Method 23 was seriously flawed, that EPA had plans to rewrite Method 23 to address those flaws, and that Method 23 did not generate scientifically valid data

. The commenter further alleged the EPA failed to inform OMB of these problems, preventing OMB from making an informed decision.

Response 2: The EPA disagrees with this comment. First, it should be noted that because the section 114 survey of the clay ceramics industry was submitted to less than nine sources, formal OMB approval of the ICR was not necessary. Second, we refer to our response in section 5.4 of thi s document refuting the commenter’ s argument that Method 23 does not generate valid D/F data for the ceramic tile industry sector. Because these D/F data are valid, we conclude that no violation of the IQA and PRA has occurred.

Comment 3: Commenter 0247 argued that the proposed D/F standard fails to satisfy the requirements of the National Technology Transfer and Advancement Act (NTTAA). EPA states that it has complied with section 12(d) of the NTTAA by accepting alternative consensus stac k testing methods for all regulated HAP , except D/F and Method 23. The docket reflects that EPA evaluated an alternative method to Method 23: EN 1948

- 3 (1996) (European Committee for Standardization)

-- Determination of the Mass Concentration of PCDD ’ S/PCDF ’ S Part 3: Identification and Quantification. 33 EPA was required to consider the limitations and inadequacies of Method 23 and provide a reasoned explanation for not adopting this voluntary standard as equal to, or as an improvement to, Method 23. EPA failed to do so. EPA is now obligated to correct its failure through the re

- proposal process.
Response 3: The EPA disagrees with the commenter that we failed to provide a reasoned explanation for not adopting EN 1948

- 3 as an alternative to EPA Method 23. As noted in Attachment 1 to the memorandum cited by the commenter , which was used as support for the EPA’s NTTAA review, EN 1948

- 3 provides additional sampling options other than what is acceptable in EPA Method 23. Consequently, it was concluded that this method would not be practical to use as an alternative to EPA Method 23. We conclude that t he EPA’s NTTAA review is sound, and no re

- proposal is necessary.

33 Voluntary Consensus Standard Results for 40 CFR Part 63, Subpart KKKKK National Emission Standards for Hazardous Air Pollutants for Clay Ceramics Manufacturing, at page 10 (June 30, 2014). Docket Item No. EPA

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- 0215.102 20.0 General Comments

Comment 1: Commenter 0246 supported, and incorporated by reference, the comments and positions prepared and submitted by the Tile Council of North America (TCNA). Commenter 0246 agre ed with the TCNA ’ s conclusion that the proposed NESHAP would, if finalized as proposed, be arbitrary and capricious.
Response 1: Commenter 0246’s support for, and incorporation by reference of, the comments from TCNA ( C ommenter 0247) are duly noted.103 21. 0 Other Comments

Comment 1: Commenter 0247 challenged EPA ’ s proposal to require the installation of an activated carbon injection (ACI) system and the proposed alternative workplace production limitations. The commenter stated both requirements are arbitra ry and capricious. The commenter noted that EPA proposed the installation of an ACI system as an option to achieve compliance with the proposed D/F and Hg emission limits ( 79 FR 75694 (col. 2) ; proposed to be codified at 40 CFR 63.8560(a) ) . In practical terms, ACI would be mandatory, not optional, because EPA proposes no other options to meet proposed D/F and Hg emission limits and the proposed no

- ACI option could effectively reduce production to the point of shutting down a major source. T he commenter contended the regulatory approach taken by EPA in proposing ACI is unlawful, and the EPA

- anticipated abatement efficiency of ACI is erroneous.

The commenter also argued that ACI is unlawfully proposed as part of EPA ’ s MACT floor analysis. CAA Section 112(d)(3)(B) requires the MACT floor to reflect the degree of reduction in HAP emissions “ achieved in practice ” by the “ five best performing sources ” in the subcategory proposed to be regulated. EPA is aware ACI is not, and has never been use d in t he ceramic tile manufacturing industry. 34 Therefore, ACI is not by definition eligible for consideration in a MACT floor analysis.

The commenter stated that ACI was eligible for consideration in a beyond

- the

- floor analysis, but noted that EPA did not perfor m a beyond

- the

- floor analysis on ACI. Had EPA performed a beyond

- the

- floor analysis on ACI, the commenter stated ACI would not have been proposed since the cost of further D/F and Hg emissions reductions would be trillions of dollars per ton of pollutant a bated. The commenter stated it would also be arbitrary and capricious for the EPA to propose ACI based on a beyond

- the

- floor analysis

. Response 1: The EPA disagrees with the commenter that we are requiring the installation of an ACI system. It is up to eac h source to determine which control methodology to employ to comply with the emission limits. ACI was not part of any MACT floor analysis, which would be inappropriate, but simply a means of estimating the potential cost and environmental impacts of MACT f loor (and beyond

- the

- floor) options

. Comment 2: Commenter 0247 challenged the use of ACI and argued the EPA should not include ACI in the final rule because the abatement efficiency is technically inaccurate and there is a lack of independent foundation for requiring ACI

. The reasons provided by the commenter support ing their statements include d :

1. The commenter noted the EPA referenced the use of ACI for abatement of Hg in waste incinerators, boilers and cement kilns and argued th e EPA failed to consid er the following differences between ceramic kilns and these other industries:

o In these other industries, Hg is in gaseous phase when activated carbon is injected ; c eramic kilns have very little organic carbon

. The EPA should have

34 Docket Item No. EPA

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- 0227, Methodology and Assumptions Used to Estimate Model Costs and Impacts of Clay Ceramics Air Pollution Control Devices, at page 6 (Nov. 6, 2014) (hereinafter “EPA Docket no. 227”)104 compared the gaseous stat e of the Hg in the comparative industries with the physicochemical state of the Hg in the ball clay matrix.

o The EPA did not investigate the use of ACI for spray dryers or tile dryers. There is no possible analogy (and none offered in the docket) between AC I usage in other industries and control of emissions from a spray dryer or tile press dryer in the ceramic tile manufacturing industry.

2. I t would be arbitrary and capricious to require ACI for ceramic tile kilns , when t he particulate emissions from spray dryers are already controlled, and ACI would be duplicative. 3. A n ACI vendor contacted by the EPA admitted ACI had not been used in the ceramic tile manufacturing industry and indicated his only experience was with gaseous Hg associated with medical wast e combustors. The docket does not show that EPA independently verified the vendor ’ s mostly inapplicable opinions and the EPA failed to ask the vendor or any independent source if ACI had been used in the context of Hg in an encapsulated solid matrix. 4. A lt hough the EPA proposed ACI as a control strategy for D/F

, one vendor offered no opinion on ACI ’ s efficacy for D/F and another vendor never responded

. 5. Although the EPA ’ s contractor stated it “ would be prudent to explore this technology ” (see EPA Docket no. 227, at page 6 (Nov. 6, 2014) ) and did not recommend ACI for the control of D/F or Hg emissions from this subcategory , the EPA never explored this technology further in the development of the proposed NESHAP. 6. The EPA previously recogniz ed that pore size is essential for ACI to be effective (see Choosing an Adsorption System for VOC: Carbon, Zeolite, or Polymers? , EPA 456/F

- 99

- 004 (May 1999). EPA cited gaseous adsorption and outline physico

- chemical parameters for gas adsorption; e.g., is otherms, vapor pressure, mass transfer, etc. F or ACI to be technically effective, the pollutant must be in a physicochemical form capable to be sorbed by the carbon . The commenter argued that Hg and D/F encapsulated in a solid ball clay matrix are not avai lable to be sorbed and therefore, ACI would be ineffective for ceramic tile kilns. The EPA ’ s contractor noted a decrease in D/F emissions associated with the application of ACI to a ceramic tile kiln in EPA Docket no. 227 at Tables F

- 8 and F

- 10 (Nov. 6, 20 14) ; however, the commenter stated the EPA had provided no mathematical or other technical foundation or support for this statement

. Response 2: As noted in our previous response, the EPA is not requiring the use of ACI to comply with the emission limits. Each source would determine how it plans to comply. Regarding the commenter’s technical comments, the commenter has provided no evidence that Hg and D/F would be completely encapsulated in a ball clay matrix and thus not available for control in the gaseous phase, either for kilns or dryers. In addition, we have stated previously that there is ample ev idence in other industries, and in similar process units (Portland cement kilns), that ACI is an effective means of reducing Hg and D/F emissions. The commenter has provided no evidence that the technology would be ineffective for the clay ceramics industr y, only conjecture

. Without any actual evidence to the contrary, we conclude that ACI is an appropriate technology for controlling Hg and D/F from the clay ceramics industry and that its inclusion in our cost and impacts analyses was entirely appropriate

.105 Comment 3: Commenter 0247 requested that EPA confirm sources may use whatever means and methods they deem necessary to demonstrate and achieve compliance with NESHAP emission limitations, including those for Hg and D/F . EPA ’ s goal should be achieving NESHA P compliance and not dictating an individual facility ’ s approach . EPA stated in the preamble that:

“ its proposal was intended to allow a regulated source to choose any control technology or technique to meet emissions limits, rather than requiring each uni t to use a prescribed control method that may not be appropriate in each case. ” ( 79 FR 75656 (col. 1)).

The commenter recommended the final NESHAP clarify that each major source in this subcategory can decide to install ACI , another type of pollution contr ol equipment or decide not to install pollution control equipment

. Procedures for monitoring, recordkeeping and reporting for control equipment other than ACI would be developed by the source and incorporated into its OM&M plan, which would be subject to r eview by EPA or the delegated

- state authority.

Response 3: The EPA agree s with the commenter that industry may use whatever means and methods they deem necessary to achieve compliance with the emission limits in the NESHAP. As noted in our previous responses in this section , it was never our intention to require sources to

use ACI to comply with the emission limits for Hg and D/F. Regarding the commenter’s request that the final NESHAP reflect that each major source in this subcategory has the right to choose to install or not install pollution c ontrol equipment other than ACI, the NESHAP already includes such provisions. While the NESHAP includes monitoring provisions for ACI, sources also have the option to use alternative monitoring procedures under 40 CFR 63.8595(h). These sources would also maintain records for approved alternative monitoring under 40 CFR 63.8640(c)(3). Compliance reports prepared and submitted under 40 CFR 63.8635 would contain information pertinent to the se alternative monitoring procedures , and t h e OM&M plan developed under 63.8575 would include the alternative control device and monitoring procedures.

Comment 4: Commenter 0247 agreed with EPA that routine maintenance, including routine maintenance of air pollution control devices

, is essential fo r air quality and the health and safety of employees and the surrounding community. It is essential for successful operation of a ceramic tile manufacturing facility as well. However, the commenter challenged EPA ’ s proposed routine control device maintenan ce approach ( 79 FR 75694 (col. 3)

- 75695 (col. 1) ; proposed to be codified at 40 CFR 63.8570(b)). The commenter contended that the proposed pre

- approval process frustrate s good air pollution control practices and force s major source s to choose between : (1) violating the NESHAP and legal enforcement for not waiting for government approval, or (2) not being able to lawfully abate unacceptable and unnecessary environmental, health and safety risks in a timely manner. The commenter recommended EPA delete the
pro pos ed EPA pre

- approval process

. The commenter was concerned that government staff will not be assigned in a timely manner, and that there will be little priority assigned to this type of review. The commenter was also concerned that those government staff that potentially would be assigned to the proposed pre

- approval process are unlikely to have the requisite background for the necessary decision making. Decisions will be delayed and be unpredictable

. Waiting to perform necessary routine maintenance is a b urden on the regulated community. EPA provided no explanation why pre

- approval is necessary and potentially defeats the goal of assur ing routine maintenance occurs in a timely manner.106 Commenter 0247 recommended 40 CFR 63.8570(d)(1) and 40 CFR 63.8570(d)(3) be deleted ( 79 FR 75695 (col. 1)). The commenter supported proposed 40 CFR 63.8570(d)(2) ( 79 FR 75695 (col. 1)), as a rewritten compliance recordkeeping requirement. An exceedence of the four percent annual limitation would be considered a deviation under a revised 40 CFR 63.8620(d).

The commenter also challenged proposed 40 CFR 63.8570(d)(4) and (d)(5) ( 79 FR 75695 (col. 1)), because they do nothing more than qualitatively emphasize behaviors already strongly encouraged by the proposed NESHAP. Their qual itative nature precludes advance notice and understanding of unlawful or prohibited conduct

, invites uncertainty in enforcement and in the assertion of defenses to enforcement , and are unnecessary.

Alternatively, C ommenter 0247 suggested EPA could modify proposed 40 CFR 63.8570(d)(1) to state that failure by the Administrator (or a delegated state agency) to make a timely decision within a short period of time, for example 15 days, constitutes approval of the routine maintenance notice. In this context, t he commenter would accept proposed 40 CFR 63.8570(d)(2) as a compliance recordkeeping requirement. An exceedence of the four percent annual limitation in proposed 40 CFR 63.8570(d)(2) would still be considered a deviation under a revised 40 CFR 63.8620(d). However, there is no basis for the proposed 40 CFR 63.8570(d)(3), (4) and (5) in this alternate scenario. T he commenter agreed with EPA that the facility would continue to operate.

Response 4 : The EPA does not agree with the commenter’s request to elimina te the pre

- approval process for the routine control device maintenance provision in 40 CFR 63.8570(d). Pre

- approval is essential to ensure that the need and timing for routine control device maintenance are justified, describe the maintenance activities an d their frequency, explain why the maintenance cannot be accomplished during source shutdowns, provide information comparing the emissions resulting from shutting down the control device to the emissions resulting from shutting down the source entirely, de scribe how the source plans to comply with applicable requirements while the control device is not operating, and provide any other documentation that the Administrator needs. EPA notes that its expectation is that this provision will be rarely invoked, be cause sources should normally conduct routine maintenance of the control device when the source is not operating.

We also disagree that the provisions in 40 CFR 63.8570(d)(4) and (5) are not needed. We have revised paragraph (d)(4) to reference the applica ble work practice standard in Table 3 of the rule that would ensure continuous compliance, including during periods of control device maintenance.

With respect to the suggestion that the EPA modify the routine maintenance provision to state that it will a pply if EPA does not act on a source’s request within a set time frame, the EPA disagrees that this would be appropriate. As we note above, it is important that the EPA ensure that this provision is appropriately applied in each case based on the informati on provided by the source. However, to address the commenter’s underlying concern that EPA might not act within sufficient time before the source would want to rely on this provision, EPA is revising the time frame for the submission of requests under this provision from 30 days as proposed (see 79 FR107 75700 (proposed section 63.8630(f)) to 120 days, which provides EPA with additional time to review and act on any requests before the source’s compliance date.

Finally, as a result of its consideration of thi s provision to address these comments, the EPA has made certain other changes to this provision, including (1) calling it an “alternative standard” rather than an “exemption” because sources covered by this provision are subject to the alternative requirem ents under this provision and are not exempt from the rule, and (2) stating the 120

- day submission period in the routine maintenance provision itself rather than only in the notification provisions.