Document ID: EPA-HQ-OAR-2010-1042-0352
Agency: epa
Document Type: Rule
Title: National Emissions Standards for Hazardous Air Pollutants: Mineral Wool Production and Wool Fiberglass Manufacturing
Posted Date: 2015-07-29T04:00Z

[Federal Register Volume 80, Number 145 (Wednesday, July 29, 2015)]
[Rules and Regulations]
[Pages 45279-45338]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-16643]

[[Page 45279]]

Vol. 80

Wednesday,

No. 145

July 29, 2015

Part II

Environmental Protection Agency

-----------------------------------------------------------------------

40 CFR Part 63

National Emissions Standards for Hazardous Air Pollutants for Mineral 
Wool Production and Wool Fiberglass Manufacturing; Final Rule

  Federal Register / Vol. 80 , No. 145 / Wednesday, July 29, 2015 / 
Rules and Regulations  

[[Page 45280]]

-----------------------------------------------------------------------

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 63

[EPA-HQ-OAR-2010-1041 and EPA-HQ-OAR-2010-1042; FRL-9928-71-OAR]
RIN 2060-AQ90

National Emissions Standards for Hazardous Air Pollutants for 
Mineral Wool Production and Wool Fiberglass Manufacturing

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This action finalizes the residual risk and technology reviews 
(RTR) conducted for the Mineral Wool Production and Wool Fiberglass 
Manufacturing source categories regulated under national emission 
standards for hazardous air pollutants (NESHAP). Under this action, we 
are establishing pollutant-specific emissions limits for hazardous air 
pollutants (HAP) that were previously regulated (under a surrogate) and 
for HAP that were previously unregulated. This action finalizes first-
time generally available control technologies (GACT) standards for gas-
fired glass-melting furnaces at wool fiberglass manufacturing 
facilities that are area sources. We are also amending regulatory 
provisions related to emissions during periods of startup, shutdown, 
and malfunction (SSM); adding requirements for reporting of performance 
testing through the Electronic Reporting Tool (ERT); and making several 
minor clarifications and corrections. The revisions in these final 
rules increase the level of emissions control and environmental 
protection provided by the Mineral Wool Production and Wool Fiberglass 
Manufacturing NESHAP.

DATES: This final action is effective on July 29, 2015.

ADDRESSES: The Environmental Protection Agency (EPA) has established 
two dockets for this action under Docket ID Nos. EPA-HQ-OAR-2010-1041 
(for 40 CFR part 63, subpart DDD) and EPA-HQ-OAR-2010-1042 (for 40 CFR 
part 63, subparts NNN and NN). All documents in these dockets are 
listed on the www.regulations.gov Web site. Although listed in the 
index, some information is not publicly available, e.g., confidential 
business information (CBI) or other information whose disclosure is 
restricted by statute. Certain other material, such as copyrighted 
material, is not placed on the Internet and will be publicly available 
only in hard copy form. Publicly available docket materials are 
available either electronically through http://www.regulations.gov, or 
in hard copy at the EPA Docket Center, EPA WJC West Building, Room 
Number 3334, 1301 Constitution Ave. NW., Washington, DC. The Public 
Reading Room hours of operation are 8:30 a.m. to 4:30 p.m. Eastern 
Time, Monday through Friday. The telephone number for the Public 
Reading Room is (202) 566-1744, and the telephone number for the Air 
and Radiation Docket and Information Center is (202) 566-1742.

FOR FURTHER INFORMATION CONTACT: For questions about this final action, 
contact Ms. Susan Fairchild, Sector Policies and Programs Division (D 
234-04), Office of Air Quality Planning and Standards, U.S. 
Environmental Protection Agency, Research Triangle Park, North 
Carolina, 27711; telephone number: (919) 541-5167; fax number: (919) 
541-5600; and email address: fairchild.susan@epa.gov. For specific 
information regarding the risk modeling methodology, contact Mr. Chris 
Sarsony, Health and Environmental Impacts Division (C539-02), Office of 
Air Quality Planning and Standards, U.S. Environmental Protection 
Agency, Research Triangle Park, North Carolina 27711; telephone number: 
(919) 541-4843; fax number: (919) 541-0840; and email address: 
sarsony.chris@epa.gov. For information about the applicability of the 
NESHAP to a particular entity, contact Ms. Sara Ayres, Office of 
Enforcement and Compliance Assurance, U.S. Environmental Protection 
Agency Region 5, 77 West Jackson Boulevard, Mail Code E-19J, Chicago, 
IL 60604-3507; telephone number: (312) 343-6266; and email address: 
ayres.sara@epa.gov.

SUPPLEMENTARY INFORMATION: 
    Preamble Acronyms and Abbreviations. We use multiple acronyms and 
terms in this preamble. While this list may not be exhaustive, to ease 
the reading of this preamble and for reference purposes, the EPA 
defines the following terms and acronyms here:

ADAF Age-dependent adjustment factors
AEGL Acute Exposure Guideline Levels
ANSI American National Standards Institute
APA Administrative Procedures Act
BDL Below detection limit
BFS Batch Formulation System
CAA Clean Air Act
CA-REL California reference exposure level
CBI Confidential business information
CDX Central Data Exchange
CEDRI Compliance and Emissions Data Reporting Interface
CEMS Continuous emission monitoring system
CFR Code of Federal Regulations
CO Carbon monoxide
COS Carbonyl sulfide
CPMS Continuous parameter monitoring system
Cr Chromium
CRA Congressional Review Act
CRT Cathode ray tube
DESP Dry electrostatic precipitator
dscm Dry standard cubic meters
EPA Environmental Protection Agency
ERPG Emergency Response Planning Guidelines
ERT Electronic Reporting Tool
ESP Electrostatic precipitator
FA Flame attenuation
FR Federal Register
GACT Generally available control technology
HAP Hazardous air pollutants
HCl Hydrogen chloride
HEPA High efficiency particulate air
HF Hydrogen fluoride
HQ Hazard quotient
ICR Information collection request
IRIS Integrated Risk Information System
Lb/ton Pounds per ton
LOI Loss on ignition
MACT Maximum achievable control technology
MDL Minimum detection limit
MIR Maximum individual risk
NAICS North American Industry Classification System
NAIMA North American Insulation Manufacturers Association
NESHAP National Emission Standards for Hazardous Air Pollutants
NOX Nitrogen oxide
NPV Net present value
NSPS New Source Performance Standards
NSSN National Standards Systems Network
NTTAA National Technology Transfer and Advancement Act
OAQPS Office of Air Quality Planning and Standards
OMB Office of Management and Budget
PB-HAP Persistent and Bioaccumulative-HAP
PM Particulate matter
ppm Parts per million
PRA Paperwork Reduction Act
RACT/BACT/LAER Reasonably Available Control Technology/Best 
Available Control Technology/Lowest Achievable Emission Rate
RCRA Resource Conservation and Recovery Act
RDL Representative detection limit
REL Recommended exposure limit
RFA Regulatory Flexibility Act
RIA Regulatory Impact Analysis
RIN Regulatory Information Number
RS Rotary spin
RTR Risk and Technology Review
SAB Science Advisory Board
SBA Small Business Administration
SBAR Small Business Analytical Review
SBREFA Small Business Regulatory Enforcement Flexibility Act
SO2 Sulfur dioxide
SSM Startup, shutdown, malfunction
TOSHI Target organ specific hazard index
TTN Technology Transfer Network
UMRA Unfunded Mandates Reform Act
UPL Upper prediction limit

[[Page 45281]]

VCS Voluntary Consensus Standards

    Background Information. On November 25, 2011 (76 FR 72770), the EPA 
proposed revisions to the Mineral Wool Production and Wool Fiberglass 
Manufacturing NESHAP based on our RTR under Clean Air Act (CAA) 
sections 112(f)(2) and (d)(6). We proposed chromium compounds emissions 
limits for wool fiberglass furnaces at major sources after finding that 
chromium refractories used to construct furnaces degrade with age and 
emit continuously-increasing levels of chromium compounds. These 
findings were the result of emissions testing conducted on these types 
of furnaces indicating significant amounts (550 pounds) of chromium 
emissions, 93 percent of which was in the hexavalent (most toxic) form. 
The furnaces tested were considered representative of all furnaces at 
each facility. In the November 2011 proposal, we also announced that we 
had already issued a new information collection request (ICR) to the 
wool fiberglass industry to collect data on chromium emissions and 
chromium refractory use at all operating wool fiberglass furnaces with 
the intent of regulating area sources in a future action.
    In the November 2011 proposal we also proposed to discontinue using 
formaldehyde as a surrogate for phenol and methanol in both the Mineral 
Wool Production and Wool Fiberglass Manufacturing source categories and 
to discontinue using carbon monoxide (CO) as a surrogate for carbonyl 
sulfide (COS) in the Mineral Wool Production source category. This 
revision was proposed because we found that the surrogate for each 
pollutant is not necessarily a reasonable representation of the 
pollutant-specific emissions for these source categories (e.g., 
formaldehyde is not invariably present in the binder formulation). We 
proposed maximum achievable control technology (MACT) standards under 
CAA sections 112(d)(2) and (3) for the HAP phenol and methanol in both 
source categories, and COS in the Mineral Wool Production source 
category. We also proposed MACT standards for hydrogen fluoride (HF) 
and hydrochloric acid (HCl), which are emitted from these source 
categories, but were not regulated under the MACT standard.
    On April 15, 2013 (78 FR 22370), the EPA issued a supplemental 
proposal that was based on comments to the November 2011 proposal and 
new information on processes in both source categories. New emissions 
test data for all wool fiberglass furnaces across the industry showed 
that the same types of furnaces were in operation at both major and 
area sources, but that the emissions profile of electric furnaces 
differed from that of gas-fired furnaces (i.e., emissions that could 
endanger public health). In that notice, we listed wool fiberglass 
manufacturing area sources, and proposed chromium emission limits for 
gas-fired wool fiberglass furnaces at area sources, and announced that 
the chromium limits at major sources would be specific to gas-fired 
furnaces (such as air-gas and oxyfuel furnaces) and not electric 
furnaces (such as cold-top and steel shell furnaces).
    On November 13, 2014 (79 FR 68012), the EPA issued a second 
supplemental proposal to explain changes to previously proposed 
emissions limits for sources in these source categories. We proposed 
work practice standards under CAA section 112(h) in lieu of certain 
emissions limits, and clarified our use of the upper predictive limit 
(UPL) in setting MACT floors. In this action, we are finalizing 
decisions and revisions for these rules. We summarize some of the more 
significant comments we received regarding the proposed rules and 
provide our responses in this preamble. A summary of all other public 
comments on the proposal and the EPA's responses to those comments is 
available in the memorandum, ``National Emissions Standards for 
Hazardous Air Pollutants: Mineral Wool Production and Wool Fiberglass 
Manufacturing (Risk and Technology Review)--Summary of Public Comments 
and Responses'' (Docket ID Nos. EPA-HQ-OAR-2010-1041 and EPA-HQ-OAR-
2010-1042). ``Track-changes'' versions of the regulatory language that 
incorporates the changes in this action are available in the respective 
dockets.

Organization of This Document

    The information in this preamble is organized as follows:

I. General Information
    A. Does this action apply to me?
    B. Where can I get a copy of this document and other related 
information?
    C. Judicial Review and Administrative Reconsideration
II. Background
    A. What is the statutory authority for this action?
    B. What is the Mineral Wool Production source category and how 
does the NESHAP regulate HAP emissions from the source category?
    C. What changes did we propose for the Mineral Wool Production 
source category in our November 25, 2011 proposal; April 15, 2013 
supplemental proposal; and November 13, 2014 supplemental proposal?
    D. What is the Wool Fiberglass Manufacturing source category and 
how does the NESHAP regulate HAP emissions from the source category?
    E. What changes did we propose for major sources in the Wool 
Fiberglass Manufacturing source category in our November 25, 2011 
proposal; April 15, 2013 supplemental proposal; and November 13, 
2014 supplemental proposal?
    F. What did we propose for area sources in the Wool Fiberglass 
Manufacturing source category in our November 25, 2011 proposal; 
April 15, 2013 supplemental proposal; and November 13, 2014 
supplemental proposal?
III. What is Included in the Final Mineral Wool Production Rule?
    A. What are the final rule amendments based on the risk review 
for the Mineral Wool Production source category?
    B. What are the final rule amendments based on the technology 
review for the Mineral Wool Production source category?
    C. What are the final rule amendments pursuant to CAA sections 
112(d)(2) and (3) for the Mineral Wool Production source category?
    D. What are the final rule amendments addressing emissions 
during periods of startup and shutdown for the Mineral Wool 
Production source category?
    E. What other changes have been made to the Mineral Wool 
Production NESHAP?
    F. What are the effective and compliance dates of the new MACT 
standards for the Mineral Wool Production source category?
    G. What are the requirements for submission of performance test 
data to the EPA?
IV. What is the rationale for our final decisions and amendments for 
the Mineral Wool Production source category?
    A. Residual Risk Review for the Mineral Wool Production Source 
Category
    B. Technology Review for the Mineral Wool Production Source 
Category
    C. MACT Standards for Pollutants Previously Regulated Under a 
Surrogate and Previously Unregulated Pollutants
    D. Startup, Shutdown, and Malfunction Provisions for the Mineral 
Wool Production Source Category
    E. Other Changes Made to the Mineral Wool Production NESHAP
V. What is Included in the Final Wool Fiberglass Manufacturing Rule 
for major sources?
    A. What are the final rule amendments based on the risk review 
for the Wool Fiberglass Manufacturing (major sources) source 
category?
    B. What are the final rule amendments based on the technology 
review for the Wool Fiberglass Manufacturing (major sources) source 
category?
    C. What are the final rule amendments pursuant to CAA sections 
112(d)(2) and (3) for the Wool Fiberglass Manufacturing (major 
sources) source category?
    D. What are the final rule amendments pursuant to CAA section 
112(h) for the

[[Page 45282]]

Wool Fiberglass Manufacturing (major sources) source category?
    E. What are the final rule amendments for the Wool Fiberglass 
Manufacturing (major sources) source category addressing emissions 
during periods of startup and shutdown?
    F. What other changes have been made to the Wool Fiberglass 
Manufacturing NESHAP (major sources)?
    G. What are the effective and compliance dates of the standards?
    H. What is the status of the Wool Fiberglass Manufacturing MACT 
standard amendments under CAA sections 112(d)(2) and (3) for RS 
Manufacturing Lines?
    I. What are the requirements for submission of performance test 
data to the EPA for the Wool Fiberglass Manufacturing NESHAP?
VI. What is the rationale for our final decisions and amendments for 
the Wool Fiberglass Manufacturing source category (major sources)?
    A. Residual Risk Review for the Wool Fiberglass Manufacturing 
Source Category (Major Sources)
    B. Technology Review for the Wool Fiberglass Manufacturing 
Source Category (Major Sources)
    C. MACT Standards for Pollutants Previously Regulated Under a 
Surrogate and Previously Unregulated Pollutants for the Wool 
Fiberglass Manufacturing Source Category (Major Sources)
    D. Work Practice Standards for HCl and HF Emissions From 
Furnaces in the Wool Fiberglass Manufacturing Source Category (Major 
Sources)
    E. Startup, Shutdown, and Malfunction Provisions for the Wool 
Fiberglass Manufacturing Source Category (Major and Area Sources)
    F. Other Changes Made to the Wool Fiberglass Manufacturing 
NESHAP (Major and Area Sources)
VII. What is included in the Final Wool Fiberglass Manufacturing 
Rule for area sources?
    A. Generally Available Control Technology (GACT) Analysis for 
Wool Fiberglass Manufacturing Area Sources
    B. What are the final requirements for the Wool Fiberglass 
Manufacturing area sources?
    C. What are the effective and compliance dates of the standards 
for Wool Fiberglass Manufacturing area sources?
    D. What are the requirements for submission of performance test 
data to the EPA for Wool Fiberglass Manufacturing area sources?
VIII. Summary of Cost, Environmental and Economic Impacts and 
Additional Analyses Conducted
    A. What are the affected facilities?
    B. What are the air quality impacts?
    C. What are the cost impacts?
    D. What are the economic impacts?
    E. What are the benefits?
    F. What analysis of environmental justice did we conduct?
    G. What analysis of children's environmental health did we 
conduct?
IX. Statutory and Executive Order Reviews
    A. Executive Orders 12866: Regulatory Planning and Review and 
Executive Order 13563: Improving Regulation and Regulatory Review
    B. Paperwork Reduction Act (PRA)
    C. Regulatory Flexibility Act (RFA)
    D. Unfunded Mandates Reform Act (UMRA)
    E. Executive Order 13132: Federalism
    F. Executive Order 13175: Consultation and Coordination With 
Indian Tribal Governments
    G. Executive Order 13045: Protection of Children From 
Environmental Health Risks and Safety Risks
    H. Executive Order 13211: Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution or Use
    I. National Technology Transfer and Advancement Act (NTTAA)
    J. Executive Order 12898: Federal Actions To Address 
Environmental Justice in Minority Populations and Low-Income 
Populations
    K. Congressional Review Act (CRA)

I. General Information

A. Does this action apply to me?

    Regulated Entities. Categories and entities potentially regulated 
by this action are shown in Table 1 of this preamble.

 Table 1--NESHAP and Industrial Source Categories Affected by This Final
                                 Action
------------------------------------------------------------------------
               NESHAP and source  category                NAICS \a\ code
------------------------------------------------------------------------
Mineral Wool Production.................................          327993
Wool Fiberglass Manufacturing...........................          327993
------------------------------------------------------------------------
\a\ North American Industry Classification System.

    Table 1 of this preamble is not intended to be exhaustive, but 
rather to provide a guide for readers regarding entities likely to be 
affected by the final action for the source categories listed. To 
determine whether your facility is affected, you should examine the 
applicability criteria in the appropriate NESHAP. If you have any 
questions regarding the applicability of any aspect of this NESHAP, 
please contact the appropriate person listed in the preceding FOR 
FURTHER INFORMATION CONTACT section of this preamble.

B. Where can I get a copy of this document and other related 
information?

    In addition to being available in the docket, an electronic copy of 
this final action will also be available on the Internet through the 
Technology Transfer Network (TTN) Web site, a forum for information and 
technology exchange in various areas of air pollution control. 
Following signature by the EPA Administrator, the EPA will post a copy 
of this final action at:  http://www.epa.gov/ttn/atw/woolfib/woolfipg 
and at http://www.epa.gov/ttn/atw/minwool/minwopg. Following 
publication in the Federal Register, the EPA will post the Federal 
Register version and key technical documents at this same Web site.
    Additional information is available on the RTR Web site at http://www.epa.gov/ttn/atw/rrisk/rtrpg.html. This information includes an 
overview of the RTR program, links to project Web sites for the RTR 
source categories and detailed emissions and other data we used as 
inputs to the risk assessments.

C. Judicial Review and Administrative Reconsideration

    Under CAA section 307(b)(1), judicial review of this final action 
is available only by filing a petition for review in the United States 
Court of Appeals for the District of Columbia Circuit by September 28, 
2015. Under CAA section 307(b)(2), the requirements established by this 
final rule may not be challenged separately in any civil or criminal 
proceedings brought by the EPA to enforce the requirements.
    Section 307(d)(7)(B) of the CAA further provides that ``[o]nly an 
objection to a rule or procedure which was raised with reasonable 
specificity during the period for public comment (including any public 
hearing) may be raised during judicial review.'' This section also 
provides a mechanism for the EPA to reconsider the rule ``[i]f the 
person raising an objection can demonstrate to the Administrator that 
it was impracticable to raise such objection within [the period for 
public comment] or if the grounds for such objection arose after the 
period for public comment (but within the time specified for judicial 
review) and if such objection is of central relevance to the outcome of 
the rule.'' Any person seeking to make such a demonstration should 
submit a Petition for Reconsideration to the Office of the 
Administrator, U.S. EPA, Room 3000, EPA, WJC West Building, 1200 
Pennsylvania Ave. NW., Washington, DC 20460, with a copy to both the 
person(s) listed in the preceding FOR FURTHER INFORMATION CONTACT 
section, and the Associate General Counsel for the Air and Radiation 
Law Office, Office of General Counsel (Mail Code 2344A), U.S. EPA, 1200 
Pennsylvania Ave. NW., Washington, DC 20460.

[[Page 45283]]

II. Background

A. What is the statutory authority for this action?

    Section 112 of the CAA establishes a two-stage regulatory process 
to address emissions of HAP from stationary sources. In the first 
stage, we must identify categories of sources emitting one or more of 
the HAP listed in CAA section 112(b) and then promulgate technology-
based NESHAP for those sources. ``Major sources'' are those that emit, 
or have the potential to emit, any single HAP at a rate of 10 tons per 
year or more, or 25 tons per year or more of any combination of HAP. 
For major sources, these standards are commonly referred to as maximum 
achievable control technology or MACT standards and must reflect the 
maximum degree of emission reductions of HAP achievable (after 
considering cost, energy requirements, and non-air quality health and 
environmental impacts). In developing MACT standards, CAA section 
112(d)(2) directs the EPA to consider the application of measures, 
processes, methods, systems or techniques, including but not limited to 
those that reduce the volume of or eliminate HAP emissions through 
process changes, substitution of materials, or other modifications; 
enclose systems or processes to eliminate emissions; collect, capture, 
or treat HAP when released from a process, stack, storage, or fugitive 
emissions point; are design, equipment, work practice, or operational 
standards; or any combination of the above.
    For these MACT standards, the statute specifies certain minimum 
stringency requirements, which are referred to as MACT floor 
requirements, and which may not be based on cost considerations. See 
CAA section 112(d)(3). For new sources, the MACT floor cannot be less 
stringent than the emission control achieved in practice by the best-
controlled similar source. The MACT standards for existing sources can 
be less stringent than floors for new sources, but they cannot be less 
stringent than the average emission limitation achieved by the best-
performing 12 percent of existing sources in the category or 
subcategory (or the best-performing five sources for categories or 
subcategories with fewer than 30 sources). In developing MACT 
standards, we must also consider control options that are more 
stringent than the floor, under CAA section 112(d)(2). We may establish 
standards more stringent than the floor, based on the consideration of 
the cost of achieving the emissions reductions, any non-air quality 
health and environmental impacts, and energy requirements.
    In the second stage of the regulatory process, the CAA requires the 
EPA to undertake two different analyses, which we refer to as the 
technology review and the residual risk review. Under the technology 
review, we must review the technology-based standards and revise them 
``as necessary (taking into account developments in practices, 
processes, and control technologies)'' no less frequently than every 8 
years, pursuant to CAA section 112(d)(6). Under the residual risk 
review, we must evaluate the risk to public health remaining after 
application of the technology-based standards and revise the standards, 
if necessary, to provide an ample margin of safety to protect public 
health or to prevent, taking into consideration costs, energy, safety, 
and other relevant factors, an adverse environmental effect. The 
residual risk review is required within 8 years after promulgation of 
the technology-based standards, pursuant to CAA section 112(f). In 
conducting the residual risk review, if the EPA determines that the 
current standards provide an ample margin of safety to protect public 
health, it is not necessary to revise the MACT standards pursuant to 
CAA section 112(f).\1\ For more information on the statutory authority 
for this rule, see the November 25, 2011, proposal (76 FR 72773).
---------------------------------------------------------------------------

    \1\ The U.S. Court of Appeals has affirmed this approach of 
implementing CAA section 112(f)(2)(A): NRDC v. EPA, 529 F.3d 1077, 
1083 (D.C. Cir. 2008) (``If EPA determines that the existing 
technology-based standards provide an 'ample margin of safety,' then 
the Agency is free to readopt those standards during the residual 
risk rulemaking.'').
---------------------------------------------------------------------------

    CAA sections 112(c)(3), (d)(5), and (k)(3) address regulation of 
area sources. Collectively, these sections are the basis of the Area 
Source Program under the Urban Air Toxics Strategy (Strategy).\2\ Area 
sources are those that emit less than the major source threshold of HAP 
(i.e., less than 10 tons per year of a single pollutant or 25 tons per 
year of a combination of HAP. Under the Strategy, we must regulate 
emissions of the 30 most toxic HAP emitted by area sources, based on 
generally available control technology (GACT), at a minimum. These 
provisions do not require the EPA to regulate all HAP from all HAP-
emitting processes as we must do when setting MACT standards. On April 
15, 2013, consistent with the Strategy, the agency added gas-fired 
glass-melting furnaces located at area sources to the source category 
list \3\ \4\ and proposed emissions standards for particulate matter 
(PM) and chromium compounds from these sources at wool fiberglass 
manufacturing facilities (78 FR 22370). On November 13, 2014, we 
withdrew our previously proposed GACT limits for PM and proposed to 
only require total chromium compounds emissions limits for these 
sources. Reduction of PM is accomplished through chromium reductions 
because chromium is the toxic pollutant entrained within PM that is 
emitted by these sources. We are finalizing GACT limits for chromium 
compound emissions for gas-fired glass-melting furnaces in the Wool 
Fiberglass Manufacturing area source category.
---------------------------------------------------------------------------

    \2\ For EPA's document on the Urban Air Toxics Strategy, see 64 
FR 38706-38715-716 (July 19, 1999).
    \3\ For the listing documents of the Strategy, see 64 FR 38075, 
July 19, 1999; 67 FR 43112, June 26, 2002; 67 FR 70427, November 22, 
2002; 73 FR 78637, December 23, 2008; and 74 FR 30366, June 25, 
2009.
    \4\ We have made several revisions to the CAA section 112(c)(3) 
list since its issuance: 67 FR 43112, June 26, 2002; 67 FR 70427, 
November 22, 2002; 73 FR 78637, December 23, 2008; 74 FR 30366, June 
25, 2009.
---------------------------------------------------------------------------

    With this regulation, pursuant to CAA sections 112(c)(3) and 
(k)(3)(B), the agency will have subjected additional sources to 
regulation for the urban metal HAP chromium compounds, which is wholly 
consistent with the goals of the Strategy. For more information on the 
statutory authority for this rule, see the November 25, 2011, 
supplemental proposal (76 FR 72770), the April 15, 2013, supplemental 
proposal (78 FR 22375-22376), and the November 13, 2014, supplemental 
proposal (79 FR 68012).

B. What is the Mineral Wool Production source category and how does the 
NESHAP regulate HAP emissions from the source category?

    The EPA promulgated the Mineral Wool Production NESHAP on June 1, 
1999 (64 FR 29490). The standards are codified at 40 CFR part 63, 
subpart DDD. The Mineral Wool Production industry consists of 
facilities that produce mineral wool fiber from slag, rock, or other 
materials, excluding sand or glass. The source category covered by this 
MACT standard currently consists of eight facilities.
    Mineral wool is a material used mainly for thermal and acoustical 
insulation. This category includes, but is not limited to, the 
following process units: A cupola furnace for melting the mineral 
charge; a blow chamber in which air and, in some cases, a binder are 
drawn over the fibers, forming them to a screen; a curing oven to bond 
the fibers; and a cooling compartment. The 1999 NESHAP rule set 
emissions limits

[[Page 45284]]

for PM from new and existing cupolas, CO from new cupolas, and 
formaldehyde from new and existing curing ovens.

C. What changes did we propose for the Mineral Wool Production source 
category in our November 25, 2011 proposal; April 15, 2013 supplemental 
proposal; and November 13, 2014 supplemental proposal?

    On November 25, 2011, the EPA published a proposed rule for the 
Mineral Wool Production NESHAP, 40 CFR part 63, subpart DDD, that 
proposed RTR amendments to this standard under CAA sections 112(d)(6) 
and (f)(2). In that proposal, we stated that maximum individual risk 
(MIR) for cancer was 4-in-1 million based on available test data for 
actual emissions and 10-in-1 million based on the MACT-allowable 
emission limits of the rule. We proposed, considering all available 
information, that risks were acceptable.
    For PM, we reviewed the control technologies in use by the industry 
and did not find any improvements or developments in practices, 
processes, and control technologies since the 1999 MACT standard was 
promulgated. Therefore, we did not propose amendments to the PM 
standards under either CAA sections 112(f)(2) or (d)(6).
    We also proposed to discontinue use of surrogates where we 
determined that the surrogacy was not reasonable. We proposed to 
discontinue using CO as a surrogate for COS, and to discontinue use of 
formaldehyde as a surrogate for phenol and methanol. Based on new 
source test data and CAA sections 112(d)(2) and (3), we proposed MACT 
floor emission limits for existing and new sources of COS, phenol, and 
methanol, pollutants that were previously regulated under a surrogate; 
and MACT floor emission limits for formaldehyde, the former surrogate. 
We retained PM as a surrogate for non-mercury HAP metals because there 
is a reasonable surrogate relationship. We also proposed emissions 
limits for HF and HCl, two pollutants that were previously unregulated, 
and proposed alternative emission limits for periods of startup and 
shutdown.
    On April 15, 2013, we published a supplemental proposal for the 
Mineral Wool Production NESHAP that took into consideration the 
comments received on the November 2011 proposal, new emissions testing 
for horizontal lines, and subcategorization of cupolas based on design 
and raw material use. We withdrew our previously-proposed alternative 
emission limits for startup and shutdown, and instead proposed that 
sources may demonstrate compliance with the MACT floor emission limits 
during periods of startup and shutdown by keeping records showing that 
the emissions from cupolas were routed to air pollution control devices 
operated at the parameters established by the most recent performance 
test that showed compliance with the standard.
    On November 13, 2014, the EPA published a second supplemental 
proposal for the Mineral Wool Production NESHAP that took into 
consideration comments received on the 2013 supplemental proposal, 
explained changes to previously proposed MACT limits for sources in 
this source category and clarified our use of the UPL in setting the 
MACT floors. In that proposal, we also proposed work practice standards 
under CAA section 112(h) for periods of startup and shutdown based on 
the practices used by the best performers among mineral wool producers 
to minimize emissions during these activities.

D. What is the Wool Fiberglass Manufacturing source category and how 
does the NESHAP regulate HAP emissions from the source category?

    The EPA promulgated the Wool Fiberglass Manufacturing NESHAP on 
June 14, 1999 (62 FR 31695). The standards are codified at 40 CFR part 
63, subpart NNN. The Wool Fiberglass Manufacturing source category is 
defined as any facility engaged in producing wool fiberglass from sand, 
feldspar, sodium sulfate, anhydrous borax, boric acid or any other 
materials. The Wool Fiberglass Manufacturing industry consists of 
facilities that produce bonded building insulation using a rotary spin 
(RS) manufacturing line, and facilities that produce bonded pipe 
insulation and bonded heavy-density products using a flame attenuation 
(FA) manufacturing line. The 1999 MACT standards currently apply to 10 
major sources in the wool fiberglass industry. Another 20 facilities 
are area sources.
    Wool fiberglass is used primarily as a thermal and acoustical 
insulation for buildings, automobiles, aircraft, appliances, ductwork 
and pipes. This category includes, but is not limited to, the following 
process units: A furnace for melting the mineral charge; a bonded line 
operation in which air and a binder are drawn over the fibers and cured 
in an oven to bond the fibers; and a cooling compartment. The 1999 
NESHAP rule set emissions limits for PM from new and existing glass-
melting furnaces and formaldehyde emissions from new FA and new and 
existing RS bonded lines.

E. What changes did we propose for major sources in the Wool Fiberglass 
Manufacturing source category in our November 25, 2011 proposal; April 
15, 2013 supplemental proposal; and November 13, 2014 supplemental 
proposal?

    On November 25, 2011, the EPA published a proposed rule for the 
Wool Fiberglass Manufacturing NESHAP to amend the standard based on our 
RTR analyses. In that proposal, we found under CAA section 112(f)(2) 
that the MIR for cancer, primarily due to emissions of hexavalent 
chromium and formaldehyde, was 40-in-1 million based on actual 
emissions and 60-in-1 million based on MACT-allowable emissions. The 
maximum chronic non-cancer target organ specific hazard index (TOSHI) 
value based on actual emissions was 0.2 with emissions of formaldehyde 
dominating those impacts. The acute noncancer hazard quotient (HQ), 
based on the recommended exposure limit (REL) for formaldehyde, was 30. 
The acute noncancer HQ, based on the Acute Exposure Guideline Levels 
(AEGL-1) for formaldehyde, was 2. We determined that nothing prevents 
construction of a high chromium emitting furnace at any wool fiberglass 
facility. Therefore, we evaluated risk under an auxiliary risk 
assessment which asked, ``if all wool fiberglass facilities emitted 
hexavalent chromium at the level of the highest emitter (that is, 450 
pounds of hexavalent chromium annually), what would be the risk to 
human health?'' The MIR under the auxiliary risk analysis exceeded 100-
in-one million at four facilities, a level we consider unacceptable.
    Although the risk from actual emissions were considered to be well 
within a level we consider acceptable, we proposed that risk due to 
hexavalent chromium could be further reduced to achieve an ample margin 
of safety. The chromium compounds limit would also prevent operation of 
another high-chromium emitting furnace in this source category. We 
therefore proposed chromium compounds emission limits of 0.00006 pounds 
of chromium compounds per ton of glass pulled, under CAA section 
112(f)(2).
    We proposed under CAA section 112(d)(6) that the control 
technologies in place on wool fiberglass manufacturing furnaces were 
essentially the same as existed at the time the MACT standards were 
promulgated, but that there have been improvements in both the 
operation and the design of furnaces and their control technologies 
since that time. As a result, we proposed

[[Page 45285]]

emissions limits for both PM and total chromium compounds for gas-fired 
glass-melting furnaces at major sources, under CAA section 112(d)(6), 
and indicated our intent to list and regulate chromium compounds at 
area sources in a future action.
    In the November 2011 proposal, similar to how we addressed the 
mineral wool source category, we also proposed in wool fiberglass to 
discontinue use of formaldehyde as a surrogate for phenol and methanol 
because the surrogacy was not reasonable. We proposed phenol, 
formaldehyde, and methanol MACT floor emission limits based on 
information collected in 2010 for two subcategories of bonded lines 
under CAA sections 112(d)(2) and (3). We proposed limits for FA lines 
that apply to all lines without further subcategorization, and proposed 
alternative emission limits for periods of startup and shutdown. In 
that notice, we also announced that we had issued an ICR under our 
section 114 authority to gather additional emission information on 
furnace chromium emissions.
    In our April 2013 supplemental proposal, we took into consideration 
comments received on the November 2011 proposal, new process and 
chromium emissions test data, and related furnace data collected under 
a CAA section 114 ICR.
    We further proposed revised PM emission limits for glass-melting 
furnaces at wool fiberglass manufacturing facilities that are major 
sources under CAA section 112(d)(6), presented the results of the new 
chromium emission testing collected from glass-melting furnaces, and 
required that the chromium emission limits proposed under CAA sections 
112(d)(6) and (f)(2) would apply only to gas-fired glass-melting 
furnaces at major sources. We proposed an alternative compliance 
provision for startup and shutdown that would require sources to keep 
records showing that emissions were routed to the air pollution control 
devices and that these control devices were operated at the parameters 
established during the most recent performance test that showed 
compliance with the applicable emission limits. For electric cold-top 
furnaces, we proposed limiting raw material content to only cullet 
during startup and shutdown in recognition of the fact that these 
furnaces do not allow control devices to be operated during startup. 
For all other glass-melting furnaces, we also required preheating the 
empty furnace using only natural gas.
    On November 13, 2014, the EPA published a second supplemental 
proposal. For major sources, the 2014 supplemental proposal took into 
consideration comments received on the 2013 supplemental proposal, 
withdrew the previously proposed amendments for affirmative defense, 
explained changes to previously proposed limits for major sources in 
this source category, proposed work practice standards under CAA 
section 112(h) for periods of startup and shutdown, and clarified our 
use of the UPL in setting MACT floors.

F. What did we propose for area sources in the Wool Fiberglass 
Manufacturing source category in our November 25, 2011 proposal; April 
15, 2013 supplemental proposal; and November 13, 2014 supplemental 
proposal?

    In the November 2011 proposal, we noted our intent to potentially 
list wool fiberglass manufacturing area sources and to use data from 
the CAA section 114 letter noted above to regulate wool fiberglass area 
sources in a future action.
    On April 15, 2013, the EPA published a supplemental proposal that 
listed gas-fired glass-melting furnaces at wool fiberglass 
manufacturing facilities that are area sources as a source category 
under CAA sections 112(c)(3)and (k)(3). We also proposed first-time PM 
and total chromium compounds standards for gas-fired glass-melting 
furnaces at wool fiberglass manufacturing facilities that are area 
sources under CAA section 112(d)(5).
    We proposed GACT standards of 0.00006 pounds of chromium compounds 
per ton of glass pulled and 0.33 pounds of PM per ton of glass pulled. 
These were the same limits that we proposed for gas-fired glass-melting 
furnaces located at major sources in the Wool Fiberglass Manufacturing 
source category. To maintain consistency with the major source rule, we 
proposed the same provisions for startup, shutdown, malfunction, 
testing, monitoring, and recordkeeping that we proposed for major 
sources.
    On November 13, 2014, the EPA published a second supplemental 
proposal. For area sources, the 2014 supplemental proposal took into 
consideration comments received on the 2013 supplemental proposal, 
withdrew the previously proposed provisions for affirmative defense, 
explained changes to previously proposed limits for sources in this 
source category, and proposed work practice standards under CAA section 
112(h) for periods of startup and shutdown.

III. What is included in the final Mineral Wool Production rule?

    This action finalizes the EPA's determinations pursuant to the RTR 
provisions of CAA section 112 for the Mineral Wool Production source 
category and amends the Mineral Wool Production NESHAP based on those 
determinations. This action also finalizes MACT emission limits under 
CAA sections 112(d)(2) and (3), work practice standards for periods of 
startup and shutdown under CAA section 112(h), and other changes to the 
NESHAP discussed in section III.E of this preamble.
    In this action, we are finalizing, as previously proposed, the 
emission limits for HAP-emitting processes in the Mineral Wool 
Production source category, as shown in Table 2 of this preamble.

                                        Table 2--Emission Limits for the Mineral Wool Production Source Category
--------------------------------------------------------------------------------------------------------------------------------------------------------
           Process                  Subcategory              HAP           2011 Proposal        2013 Proposal        2014 Proposal         Final rule
--------------------------------------------------------------------------------------------------------------------------------------------------------
Cupolas......................  Existing Open-top....  COS.............  3.3................  6.8................  No change..........  6.8
                               New Open-top.........  COS.............  0.017..............  4.3................  3.2................  3.2
                               Existing Closed-top..  COS.............  3.3................  3.4................  No change..........  3.4
                               New Closed-top.......  COS.............  0.017..............  0.025..............  0.062..............  0.062
                               Existing Processing    HF..............  0.014..............  0.16...............  No change..........  0.16
                                Slag.
                                                      HCl.............  0.0096.............  0.21...............  0.44...............  0.44
                               New Processing Slag..  HF..............  0.014..............  0.16...............  0.015..............  0.015
                                                      HCl.............  0.0096.............  0.21...............  0.012..............  0.012
                               Existing Not           HF..............  0.014..............  0.13...............  No change..........  0.13
                                Processing Slag.
                                                      HCl.............  0.0096.............  0.43...............  No change..........  0.43
                               New Not Processing     HF..............  0.014..............  0.13...............  0.018..............  0.018
                                Slag.
                                                      HCl.............  0.0096.............  0.43...............  0.015..............  0.015

[[Page 45286]]

 
Bonded Lines.................  Vertical (Existing     Formaldehyde....  0.46...............  2.7................  2.4................  2.4
                                and New) Combined     Phenol..........  0.52...............  0.74...............  0.71...............  0.71
                                Collection and        Methanol........  0.63...............  1.0................  0.92...............  0.92
                                Curing Operations.
                               Horizontal (Existing   Formaldehyde....  0.054..............  No change..........  0.63...............  0.63
                                and New) Combined     Phenol..........  0.15...............  No change..........  0.12...............  0.12
                                Collection and        Methanol........  0.022..............  No change..........  0.49...............  0.49
                                Curing Operations.
                               Drum (Existing and     Formaldehyde....  0.067..............  0.18...............  0.17...............  0.17
                                New) Combined         Phenol..........  0.0023.............  1.3................  0.85...............  0.85
                                Collection and        Methanol........  0.00077............  0.48...............  0.28...............  0.28
                                Curing Operations.
--------------------------------------------------------------------------------------------------------------------------------------------------------

A. What are the final rule amendments based on the risk review for the 
Mineral Wool Production source category?

    As presented in the November 2014 supplemental proposal, we are 
finalizing our determination that risks from the Mineral Wool 
Production source category are acceptable, the current standards 
provide an ample margin of safety to protect public health and prevent 
an adverse environmental effect. We are, therefore, not requiring 
additional controls and are thus readopting the existing standards 
under section 112(f)(2).

B. What are the final rule amendments based on the technology review 
for the Mineral Wool Production source category?

    As discussed in the November 2011 proposal (76 FR 72786-72787, 
72798), we identified and evaluated the developments in practices, 
processes, and control technologies that have occurred since the 1999 
MACT rules were promulgated. In cases where we identified such 
developments, we analyzed the technical feasibility and the estimated 
impacts (e.g., costs, emissions reductions, risk reductions) of 
applying these developments. We then decided, based on impacts and 
feasibility, whether it was necessary to propose amendments to the 
regulation to require any of the identified developments.
    Based on our analyses of the data, information collected under the 
voluntary ICR, our general understanding of both of the industries and 
other available information on potential controls for these industries, 
we identified potential developments \5\ in practices, processes, and 
control technologies.
---------------------------------------------------------------------------

    \5\ For the purpose of this exercise, we considered developments 
not identified or considered during development of the 1999 MACT 
rules, including any add-on control technology or equipment; any 
improvements in technology or equipment that could result in 
significant additional emissions reduction; any work practice or 
operational procedure; any process change or pollution prevention 
alternative that could be broadly applied to the industry; and any 
development in equipment or technology that could result in 
decreased HAP emissions.
---------------------------------------------------------------------------

    In addition to reviewing the practices, processes, and technologies 
that were not considered at the time we developed the 1999 MACT rules, 
we reviewed a variety of data sources for the mineral wool industry. 
This review included the NESHAP for various industries promulgated 
after the 1999 MACT rules, regulatory requirements and technical 
analyses associated with these regulatory actions to identify any 
practices, processes, and control technologies considered in these 
efforts that could possibly be applied to emissions sources in the 
Mineral Wool Production source category, as well as the costs, non-air 
impacts, and energy implications associated with the use of these 
technologies.
    We additionally consulted the EPA's Reasonably Available Control 
Technology/Best Available Control Technology/Lowest Achievable Emission 
Rate (RACT/BACT/LAER) Clearinghouse to identify potential technology 
advances, and searched this database to determine whether it contained 
any practices, processes, or control technologies for the types of 
processes covered by the mineral wool production rule.
    We also requested information from facilities regarding 
developments in practices, processes or control technologies and we 
reviewed other information sources, such as state and local permitting 
agency databases and industry-supported databases. For more 
information, see the ``Technology Review for the Mineral Wool 
Production Source Category Memorandum'' in the docket to this rule.
    As a result of our technology review under CAA section 112(d)(6) 
for the Mineral Wool Production source category, we determined that 
there are no developments in practices, processes, and control 
technologies that warrant revisions to this MACT standard. We are 
therefore not amending the standards under CAA section 112(d)(6).

C. What are the final rule amendments pursuant to CAA sections 
112(d)(2) and (3) for the Mineral Wool Production source category?

    This action finalizes the removal of formaldehyde as a surrogate 
for phenol and methanol, and the removal of CO as a surrogate for COS, 
as earlier explained in this preamble and as proposed on November 25, 
2011 (76 FR 72770). We also are finalizing the proposed COS, HCl, and 
HF emission limits for cupolas and the proposed emission limits for 
formaldehyde, methanol, and phenol for bonded lines developed as a 
result of new representative detection limit (RDL) values, new source 
test data and our approach for calculating MACT floors based on limited 
data sets, as discussed in section III.B of the November 2014 
supplemental proposal preamble. These final rule requirements for the 
Mineral Wool Production NESHAP are consistent with the provisions 
discussed in our various proposals.

D. What are the final rule amendments addressing emissions during 
periods of startup and shutdown for the Mineral Wool Production source 
category?

    We are finalizing, as proposed, amendments to the Mineral Wool 
Production NESHAP to eliminate the SSM exemption. Consistent with 
Sierra Club v. EPA, 551 F. 3d 1019 (D.C. Cir. 2008), the EPA has 
established work practice standards for periods of startup and shutdown 
under CAA section 112(h) because measurement of the emissions is not 
practicable due to technological and economic limitations. Emissions 
are not at steady state during startup and shutdown (a necessary factor 
for accurate emissions testing), and the varying stack conditions, gas 
compositions and low emission rates make accurate emission measurements 
impracticable. In addition, the startup period for mineral wool cupolas 
is usually 2 hours, which is too short a

[[Page 45287]]

time in which to conduct source testing. We are finalizing under CAA 
section 112(h), as previously proposed in the November 2014 
supplemental proposal, standards requiring affected sources to comply 
with work practices that are used by the best performers during periods 
of startup and shutdown. The best performers in the mineral wool 
industry use one of two possible work practices: either they route any 
cupola emissions that occur during startup and shutdown to an operating 
baghouse, or, alternatively, operate the cupola during startup and 
shutdown with three percent excess oxygen. Regarding the first 
alternative, baghouses achieve the same outlet concentrations 
regardless of pollutant loading in the emission stream, and 
fluctuations in pollutants or exhaust flow rate do not affect the 
overall level of emissions at the outlet of this control device. 
Regarding the second alternative, operating the cupola with excess 
oxygen prevents the formation of pollutants that would otherwise be 
routed to existing controls.
    In the final rule, we are specifying work practice standards that 
require items of equipment that are required or utilized for compliance 
with subpart DDD to be operating during startup and shutdown, 
designating when startups and shutdowns begin, and specifying 
recordkeeping requirements for startup and shutdown periods. We are 
also revising Table 1 to subpart DDD of part 63 (General Provisions 
applicability table) to change several references related to 
requirements that apply during periods of SSM. We are eliminating or 
revising certain recordkeeping and reporting requirements related to 
the eliminated SSM exemption.

E. What other changes have been made to the Mineral Wool Production 
NESHAP?

    We are finalizing, as proposed, addition of EPA Methods 26A and 320 
in appendix A part 63 for measuring the concentrations of HCl and HF. 
We are finalizing, as proposed, the requirement for existing sources to 
conduct performance tests to demonstrate compliance with the emission 
limits for cupolas and combined collection/curing operations no later 
than July 30, 2018 and every 5 years thereafter. We are finalizing, as 
proposed, the requirement for new sources to comply with the emission 
limits of the final rule on July 29, 2015, or upon the first cupola 
campaign, whichever is later, and to conduct performance tests to 
demonstrate compliance with the emission limits for cupolas and 
combined collection/curing operations within 180 days of the applicable 
compliance date.
    We are also adding an alternative operating limit for cupolas that 
provides owners or operators the option of maintaining the percent 
excess oxygen in the cupola at or above the level established during 
the performance test. In addition, we are finalizing editorial changes 
to the performance testing and compliance procedures to specify 
formaldehyde, methanol, phenol, and COS rather than only the surrogates 
formaldehyde and CO. In this action, we are finalizing, as proposed, 
definitions for ``closed-top cupola,'' ``open-top cupola,'' ``combined 
collection/curing operations'' and ``incinerator.'' We are also adding 
a definition for ``slag.'' The 2013 supplemental proposal indicated 
that we would add such a definition (78 FR 22386). Slag is the primary 
contributing factor to the formation of HF and HCl in the cupola 
emissions, and is, for some mineral wool formulas, a necessary 
ingredient for the production of mineral wool. We subcategorized 
cupolas according to their use of slag as a raw material in the cupola, 
and are in this final rule defining slag in 40 CFR 63.1196 to mean the 
by-product materials separated from metals during smelting and refining 
of raw ore.
    We are also making minor corrections to the citations in Table 1 
(part 63 General Provision applicability table) to reflect both the 
final amendments in this action, and the revisions that have been made 
to the General Provisions since 1999.

F. What are the effective and compliance dates of the new MACT 
standards for the Mineral Wool Production source category?

    The new MACT standards for the Mineral Wool Production source 
category being promulgated in this action are effective on July 29, 
2015. The compliance date for existing cupolas and combined collection/
curing operations is July 30, 2018. New sources must comply with the 
all of the standards immediately upon the effective date of the 
standard, July 29, 2015, or upon initial startup, whichever is later.
    Mineral wool producers are predominantly small businesses. Prior to 
the November 25, 2011, proposal, we found there was potentially a 
significant impact to a substantial number of small entities (SISNOSE), 
and convened a small business advocacy review (SBAR) panel. In that 
process, the EPA conducted meetings with mineral wool companies and the 
Small Business Office of Advocacy in order to determine ways in which 
the impact and burden to small entities could be reduced while 
continuing to meet the requirements of the CAA. Stakeholders requested 
up to 3 years to comply with the standards once they were promulgated, 
in order to be able to install controls, find sources of low-sulfur 
coke and low-chloride slag, and to conduct performance testing. In 
subsequent proposals, we subcategorized cupolas according to design and 
according to raw material use, and can certify that the final rule will 
not have a SISNOSE. However, we believe that it is still appropriate to 
retain the proposed compliance date of 3 years after promulgation 
because the added compliance emissions testing and any process changes 
sources needed to comply could become significant if the compliance 
time were shortened to less than the 3 years allowed for standards 
developed under CAA sections 112(d)(2) and (3).

G. What are the requirements for submission of performance test data to 
the EPA?

    As stated in the proposed preamble to the November 2011 proposal, 
the EPA is taking a step to increase the ease and efficiency of data 
submittal and data accessibility. Specifically, the EPA is requiring 
owners and operators of affected facilities to submit electronic copies 
of certain required performance test reports.
    As mentioned in the preamble of the November 2011 proposal, data 
will be collected by direct computer-to-computer electronic transfer 
using EPA-provided software. As discussed in the November 2011 
proposal, the EPA-provided software is an electronic performance test 
report tool called the ERT. The ERT will generate an electronic report 
package which will be submitted to the Compliance and Emissions Data 
Reporting Interface (CEDRI) and then archived to the EPA's Central Data 
Exchange (CDX). A description and instructions for use of the ERT can 
be found at http://www.epa.gov/ttn/chief/ert/index.html, and CEDRI can 
be accessed through the CDX Web site at http://www.epa.gov/cdx.
    The requirement to submit performance test data electronically to 
the EPA does not create any additional performance testing and will 
apply only to those performance tests conducted using test methods that 
are supported by the ERT. A listing of the pollutants and test methods 
supported by the ERT is available at the ERT Web site. The EPA 
believes, through this approach, industry will save time in the

[[Page 45288]]

performance test submittal process. Additionally, this rulemaking 
benefits industry by cutting back on recordkeeping costs as the 
performance test reports that are submitted to the EPA using CEDRI are 
no longer required to be kept in hard copy.
    As mentioned in the preamble of the November 2011 proposal, state, 
local, and tribal agencies will benefit from more streamlined and 
accurate review of performance test data that will be available on the 
EPA WebFIRE database. The public will also benefit. Having these data 
publicly available enhances transparency and accountability. For a more 
thorough discussion of electronic reporting of performance tests using 
direct computer-to-computer electronic transfer and using EPA-provided 
software, see the discussion in the preamble of the November 2011 
proposal.
    In summary, in addition to supporting regulation development, 
control strategy development, and other air pollution control 
activities, having an electronic database populated with performance 
test data will save industry; state, local, and tribal agencies; and 
the EPA significant time, money, and effort, while improving the 
quality of emission inventories, air quality regulations and enhancing 
the public's access to this important information.

IV. What is the rationale for our final decisions and amendments for 
the Mineral Wool Production source category?

    For each topic, this section provides a description of what we 
proposed and what we are finalizing for the subject, the EPA's 
rationale for the final decisions and amendments and a summary of key 
comments and responses. For all comments not discussed in this 
preamble, comment summaries and the EPA's responses can be found in the 
comment summary and response document available in the dockets for each 
source category.

A. Residual Risk Review for the Mineral Wool Production Source Category

1. What did we propose pursuant to CAA section 112(f) for the Mineral 
Wool Production source category?
    Pursuant to CAA section 112(f), we conducted a residual risk 
assessment on the Mineral Wool Production source category and presented 
the results of this assessment, along with our proposed decisions 
regarding risk acceptability and ample margin of safety, in the 
November 2011 proposed rule (76 FR 72798). Based on the inhalation risk 
assessment, we estimated that the MIR could be up to 4-in-1 million due 
to actual emissions and up to 10-in-1 million due to MACT-allowable 
emissions, mainly due to formaldehyde stack emissions. We estimated 
that the incidence of cancer based on actual emissions is 0.0004 excess 
cancer cases per year or one case every 2,500 years, and that about 
1,700 people face a cancer risk greater than 1-in-1 million due to HAP 
emissions from the mineral wool production source category.
    That risk assessment indicated that the maximum modeled chronic 
non-cancer TOSHI value for the Mineral Wool Production source category 
could be up to 0.04 with emissions of formaldehyde dominating those 
impacts, indicating no significant potential for chronic non-cancer 
impacts.
    Our screening analysis for worst-case acute impacts indicated the 
potential for only one pollutant, formaldehyde, to exceed an HQ value 
of 1 at only one facility in the Mineral Wool Production source 
category, with a potential maximum HQ up to 8. A refined emissions 
multiplier of 3 was used to estimate the peak hourly emission rates 
from the average rates.
    Consequently, in November 2011 we proposed that risks from this 
source category were acceptable. In addition, we did not identify cost-
effective options that would further reduce risk under our ample margin 
of safety analysis. Therefore, we proposed that the current standards 
for the Mineral Wool Production source category provide an ample margin 
of safety to protect public health. We also determined that HAP 
emissions from this source category were not expected to result in 
adverse environmental effects.
    In the April 2013 supplemental proposal, we revised the risk 
assessment to reflect new emissions data submitted by the industry 
following the 2011 proposal, the development of subcategories for HCl 
and HF emissions from slag- and nonslag-processing cupolas, and 
subcategories for COS emissions from closed- and open-top cupolas. As 
noted in the 2013 supplemental proposal, the risks estimated in our 
revised assessment under CAA section 112(f)(2) from actual emissions 
increased slightly (based on the new data) compared to the risk 
assessment conducted for the 2011 proposal. The actual MIR for cancer 
increased from 4-in-1 million to 10-in-1 million. The maximum chronic 
non-cancer TOSHI value for the source category increased from 0.04 to 
0.12 with emissions of formaldehyde dominating those impacts, 
indicating no significant potential for chronic noncancer impacts. The 
acute noncancer HQ, based on the REL for formaldehyde, increased from 8 
to 20. The acute noncancer HQ, based on the AEGL-1 for formaldehyde, 
increased from 0.4 to 1.1. While the risk increased slightly based on 
the new source test data, we noted that that our findings regarding 
risk acceptability and ample margin of safety remained unchanged.
    In our November 2014 supplemental proposal, we also revised the 
draft risk assessment under CAA section 112(f)(2) based on new 
emissions data collected by the industry and updates to the model and 
model libraries. The new test data that were received did not change 
our estimate of risk from actual emissions when compared to the risk 
assessment conducted for the 2013 supplemental proposal. The risk from 
mineral wool production continued to be driven by formaldehyde and to 
be well within a level we consider to be acceptable. The MIR for cancer 
for actual baseline emissions remained 10-in-1 million, with the acute 
noncancer HQ remaining at 20 for the REL and at 1 for the AEGL-1. The 
maximum chronic non-cancer TOSHI value based on actual emissions 
remained at 0.1 with emissions of formaldehyde dominating those 
impacts, indicating no significant potential for chronic noncancer 
impacts.
    The MIR for cancer from mineral wool production due to allowable 
emissions (under the original MACT standard) was estimated to be 30-in-
1 million (formaldehyde). Facilities actually emit formaldehyde at 
levels lower than allowed under the 1999 MACT standard, and the limits 
in the final rule codify formaldehyde (and the other HAP) limits at the 
actual emissions levels. As a result, the potential MIR for cancer due 
to allowable emissions after implementation of the standard is 
estimated to be 10-in-1 million. Therefore, the MIR based on emissions 
at the level of this standard (i.e., what sources are permitted to 
emit) decreased by a factor of 3 from MACT-allowable levels. Additional 
information on the risk assessment can be found in the document titled, 
``Residual Risk Assessment for the Mineral Wool Production and Wool 
Fiberglass Manufacturing in Support of the June 2015 Final Rule'' 
available in the docket for this action (EPA-HQ-OAR-2010-1041).

[[Page 45289]]

2. How did the risk review change for the Mineral Wool Production 
source category?
    We have not changed any aspect of the risk assessment since the 
November 2014 supplemental proposal.
3. What key comments did we receive on the risk review for the Mineral 
Wool Production source category, and what are our responses?
    The comments received on the proposed risk review were generally 
supportive of our determination of risk acceptability and ample margin 
of safety analysis and requirement for additional control. A summary of 
the comments received regarding the risk acceptability and ample margin 
of safety analysis and our responses can be found in the comment 
summary and response document available in the docket for this action 
(EPA-HQ-OAR-2010-1041). None of the public comments resulted in changes 
to the conclusions of our risk analysis.
4. What is the rationale for our final approach and final decisions for 
the risk review for the Mineral Wool Production source category?
    As explained in the various proposals and in section IV.A.1 of this 
preamble, our assessment of residual risk from the Mineral Wool 
Production source category shows that risks from the source category 
are acceptable, the current standards provide an ample margin of safety 
to protect public health, and prevent an adverse environmental effect. 
We are, therefore, not requiring additional controls and are thus 
readopting the existing standards under section 112(f)(2).

B. Technology Review for the Mineral Wool Production Source Category

1. What did we propose pursuant to CAA section 112(d)(6) for the 
Mineral Wool Production source category?
    Pursuant to CAA section 112(d)(6), we conducted a technology review 
that focused on identifying and evaluating developments in practices, 
processes, and control technologies for sources of HAP in the Mineral 
Wool Production source category. As discussed in the 2011 proposal (76 
FR 72798), existing cupolas are controlled using baghouses, and bonded 
lines are controlled using thermal oxidizers. We did not identify any 
relevant cost-effective developments in technologies, practices, or 
processes since promulgation of the 1999 NESHAP that would further 
reduce HAP emissions. Therefore, we did not propose any changes to the 
1999 NESHAP as a result of our technology review under CAA section 
112(d)(6) for the Mineral Wool Production source category. Additional 
information regarding the technology review for the Mineral Wool 
Production source category can be found in the document titled, 
``Section 112(d)(6) Technology Review for the Final Mineral Wool 
NESHAP'' available in the docket for this action (EPA-HQ-OAR-2010-
1041).
2. How did the technology review change for the Mineral Wool Production 
source category?
    We have not changed any aspect of the technology review for this 
source category since the November 2014 supplemental proposal.
3. What key comments did we receive on the technology review, and what 
are our responses?
    The comments received on our technology review and findings were 
generally supportive. A summary of the comments received regarding the 
technology review and our responses can be found in the comment summary 
and response document available in the docket for this action (EPA-HQ-
OAR-2010-1041). We note that none of the public comments and 
information received in response to the November 2014 supplemental 
proposal provided data relevant to the technology review, and we made 
no changes to the technology review based on the comments.
4. What is the rationale for our final approach for the technology 
review?
    As explained in the various proposals and in section IV.B.1 of this 
preamble, we did not identify any cost-effective developments in 
practices, processes and controls used to reduce emissions from the 
mineral wool production industry. Therefore, consistent with our 
proposals, we are not making any changes to the standards as a result 
of the CAA section 112(d)(6) review.

C. MACT Standards for Pollutants Previously Regulated Under a Surrogate 
and Previously Unregulated Pollutants

1. What did we propose pursuant to CAA section 112(d)(2) and (3) for 
pollutants previously regulated under a surrogate and for previously 
unregulated pollutants?
    In our November 2011 proposal, we proposed revisions to the 1999 
NESHAP under CAA sections 112(d)(2) and (3). We proposed to remove 
unreasonable surrogates, to set limits for each HAP emitted that was 
previously regulated under a surrogate, and to set limits for 
previously unregulated HAP. These revisions included removing CO as a 
surrogate for COS and removing formaldehyde as a surrogate for methanol 
and phenol; proposing emission limits for COS from cupolas, 
formaldehyde, methanol, and phenol from combined collection and curing 
operations; and proposing emissions limits for previously unregulated 
pollutants (i.e., HCl and HF emitted from cupolas).
    In our April 2013 supplemental proposal, we made changes to the 
previously proposed emission limits for phenol, formaldehyde, and 
methanol based on new emissions test data. We further proposed 
subcategories for COS emissions from cupolas based on cupola design. 
Finally, we proposed subcategories for HF and HCl from cupolas based on 
whether they processed slag.
    In the November 2014 supplemental proposal, we revised emission 
limits under CAA sections 112(d)(2) and (3) for cupolas and bonded 
lines as a result of new information regarding detection limits (and 
consistent with our procedures for ensuring that emission limits are 
not set below the minimum level that can be accurately measured), new 
source test data and our approach for calculating MACT floors based on 
limited data sets.
2. How did we change our proposed emission limits for pollutants that 
were previously regulated under a surrogate or that were previously 
unregulated?
    Our final emission limits for pollutants previously regulated under 
a surrogate, and previously unregulated pollutants did not change since 
our most recent proposal in November 2014.
3. What key comments did we receive on pollutants previously regulated 
under a surrogate and on previously unregulated pollutants?
    We received comments both supporting and objecting to our use of 
the UPL in calculating MACT floors and the way we treat limited 
datasets for these pollutants. The commenters did not provide new 
information or a basis for the EPA to change the proposed emission 
limits, and did not show that facilities cannot comply with the MACT 
standards. The comments related to the proposed emission limits for 
pollutants that were previously regulated under a surrogate and that 
were previously unregulated are in the comment summary and the response 
document available in the docket for this action (EPA-HQ-OAR-2010-
1041).

[[Page 45290]]

4. What is the rationale for our final approach for pollutants 
previously regulated under a surrogate and for previously unregulated 
pollutants?
    As we discussed in the preamble for the November 2014 supplemental 
proposal and provided in the comment summary and response document 
available in the docket, we are finalizing, as proposed, the emission 
limits for pollutants previously regulated under a surrogate and for 
previously unregulated pollutants. Three surrogate relationships were 
in place in the Mineral Wool MACT standard, and we reviewed each of 
these to determine whether they were reasonable surrogates. We found 
that the relationship of formaldehyde, methanol and phenol emissions 
tend to be specific to the binder formulation of an individual product. 
We found that the surrogacy of CO for COS was not reasonable because 
the two pollutants are not invariably present and the relationships 
tend to be specific to the site. We retained the surrogacy of PM for 
non-mercury HAP metals because control of PM achieves the same level of 
control for non-mercury HAP metals, regardless of the concentration of 
those metals in the PM or whether the concentration of those metals 
varies in the PM.
    We requested and obtained HAP-specific emissions testing for all 
HAP emitted by all processes in the mineral wool industry. Emissions of 
PM, HF, HCl, and COS were measured from at least one cupola in 
operation at each facility, and emissions of formaldehyde, methanol, 
and phenol were measured at the three bonded lines that were in 
operation in 2010. As a result of the information we gathered, we are 
finalizing limits for all measured HAP and for the collection process, 
which emits HAP but was not regulated under the 1999 MACT standard. We 
are not changing the PM emission limit as a result of the information 
we gathered.
    HF and HCl were not previously regulated, and the emissions of 
these pollutants depend upon whether slag is used in the cupola. Slag 
is a raw material in the mineral wool industry that is a waste product 
of electric arc furnaces at steel plants. Depending on the end-use of 
the mineral wool product, slag is a needed ingredient in some mineral 
wool formulations and an undesirable ingredient in others. The use of 
slag as a raw material in the mineral wool cupola causes ``shot'' 
(small pellets of iron) to form in the mineral wool product. The 
quality of some mineral wool products (such as that used for hydroponic 
gardening) is affected by the presence of shot, and, as a result, 
facilities making such products do not use slag in their raw materials. 
Consequently, their emissions of HF and HCl are lower. Two 
subcategories of cupolas reflect whether slag is processed in the 
cupola.
    Emissions of COS are affected by whether a cupola is designed as a 
closed cupola (which results in lower COS emissions) or an open cupola 
(which results in higher COS emissions). Two subcategories of cupolas 
reflect this design criteria.
    Data collected from the mineral wool industry showed three bonded 
lines were in operation at the time of data collection in 2010. The 
bonded lines include both collection (the process in which the fibers 
are formed and sprayed with a phenol/formaldehyde binding agent); and 
curing, the thermosetting process that cures the binder. Collection was 
not regulated under the 1999 MACT standard, the emissions from both the 
curing and collection processes are vented to the same line, and the 
emissions from these processes can be measured together. These combined 
collection and curing operations emit phenol, formaldehyde, and 
methanol as a result of the phenolic resin used to produce the bonded 
product. We are finalizing limits for combined collection and curing 
operations according to three different designs: Vertical, horizontal, 
and drum. The final emission limits for the mineral wool industry are 
shown above in Table 2 of section III of this preamble.

D. Startup, Shutdown, and Malfunction Provisions for the Mineral Wool 
Production Source Category

1. What SSM provisions did we propose for the Mineral Wool Production 
source category?
    In its 2008 decision in Sierra Club v. EPA, 551 F.3d 1019 (D.C. 
Cir. 2008), the United States Court of Appeals for the District of 
Columbia Circuit vacated portions of two provisions in the EPA's CAA 
section 112 regulations governing the emissions of HAP during periods 
of SSM. Specifically, the Court vacated the SSM exemption contained in 
40 CFR 63.6(f)(1) and 40 CFR 63.6(h)(1), holding that under section 
302(k) of the CAA, emissions standards or limitations must be 
continuous in nature and that the SSM exemption violates the CAA's 
requirement that some CAA section 112 standards apply continuously.
    We have therefore eliminated the SSM exemption in this rule. 
Consistent with Sierra Club v. EPA, the EPA has established work 
practice standards for those periods. We also revised Table 1 of the 
General Provisions applicability table in several respects as is 
explained in more detail below. For example, we have eliminated the 
incorporation of the General Provisions' requirement that the source 
develop an SSM plan. We also eliminated and revised certain 
recordkeeping and reporting provisions that are related to the SSM 
exemption as described in detail in the proposed rule and summarized 
again in section IV.D of this preamble, in the rule at 40 CFR 63.1389, 
and in the General Provisions Table 1 to subpart DDD of part 63 (40 CFR 
part 63, subpart A).
2. How did the SSM provisions change for the Mineral Wool Production 
source category?
    We have not changed any aspect of the proposed SSM provisions since 
the November 2014 supplemental proposal.
3. What key comments did we receive on the SSM provisions, and what are 
our responses?
    We received comments regarding the proposed revisions to remove the 
SSM exemptions for the Mineral Wool Production source category. 
Comments from industry representatives expressed support for the 
proposed work practice standards. Another commenter contended that we 
should have established numerical emission limits. As we noted in the 
November 2014 supplemental proposal (79 FR 68016), the EPA may 
promulgate a work practice rather than an emissions standard when 
measurement of the emissions is technically and economically 
practicable. In the case of this source category, emissions are not at 
steady state during startup and shutdown (a necessary factor for 
accurate emissions testing), and the varying stack conditions, gas 
compositions, and flow rates make accurate emission measurements 
impracticable. In addition, startup period for mineral wool cupolas, 
typically 2 hours, is too short a time to conduct source testing.
    The commenters did not provide new information or a basis for the 
EPA to change the proposed provisions and did not show that facilities 
cannot comply with the work practice standards during periods of 
startup and shutdown. The comments related to the proposed revisions to 
remove the SSM exemptions and our specific responses to those comments 
can be found in the comment summary and response document available in 
the docket for this action (EPA-HQ-OAR-2010-1041).

[[Page 45291]]

4. What is the rationale for our final decisions for the SSM 
provisions?
    For the reasons provided above, in the preamble for the proposed 
rule and provided in the comment summary and response document 
available in the docket, we have removed the SSM exemption from the 
Mineral Wool Production NESHAP; eliminated or revised certain 
recordkeeping and reporting requirements related to the eliminated SSM 
exemption; and removed or modified inappropriate, unnecessary, or 
redundant language in the absence of the SSM exemption. For periods of 
startup and shutdown, we are finalizing the work practices of the best 
performers, as proposed in the November 2014 supplemental proposal. 
Owners/operators may choose to comply using two potential options 
during startup and shutdown. One, cupola emissions may be controlled 
using the control devices that meet the limits of the standard during 
normal operation, or two, the cupola may be operated during startup and 
shutdown with 3 percent or more excess oxygen. Additionally, sources 
must maintain records of the startup and shutdown option they practice, 
and must monitor and keep records of the parameters of the operating 
control device(s) or the oxygen level of the cupola during these 
periods. The controls of startup and shutdown emissions practiced by 
the best performers in the source category are sufficient so that no 
additional standards are needed to address emissions during startup or 
shutdown periods.

E. Other Changes Made to the Mineral Wool Production NESHAP

1. What other changes did we propose for the Mineral Wool Production 
NESHAP?
a. Electronic Reporting
    As stated in the preamble to the November 2011 proposed rule, the 
EPA proposed electronic reporting requirements. See section III.G of 
this preamble for more information on what we proposed (and what we are 
finalizing) for electronic reporting.
b. Test Methods and Testing Frequency
    We are finalizing, as proposed, the requirement for new sources to 
conduct performance tests to demonstrate compliance with the emission 
limits for cupolas and combined collection/curing operations within 180 
days of the applicable compliance date and every 5 years thereafter. We 
are finalizing, as proposed, the requirement for existing sources to 
conduct performance tests to demonstrate compliance with the emission 
limits for cupolas and combined collection/curing operations by July 
30, 2018 and every 5 years thereafter. We are finalizing, as proposed, 
the addition of EPA Methods 26A and 320 in appendix A of part 63 for 
measuring the concentrations of HCl and HF; and EPA Method 318 for 
measuring the concentrations of COS, formaldehyde, methanol, and 
phenol. In addition, we are finalizing editorial changes to the 
performance testing and compliance procedures to replace references in 
the 1999 NESHAP to the surrogates CO and formaldehyde with references 
to specific HAP (formaldehyde, methanol, and phenol for the surrogate 
formaldehyde, and COS for the surrogate CO).
2. How did the provisions regarding these other changes to the Mineral 
Wool Production NESHAP change since proposal?
    We have not made any changes to the proposed provisions for 
electronic reporting; testing methods and frequency; definitions or 
revisions to the General Provision applicability table.
3. What key comments did we receive on the other changes to the Mineral 
Wool Production NESHAP, and what are our responses?
    We received no key comments regarding electronic reporting, testing 
methods and frequency, definitions, and revisions to the General 
Provisions applicability table. A summary of the comments we did 
receive and our responses can be found in the comment summary and 
response document available in the docket for this action (EPA-HQ-OAR-
2010-1041).
4. What is the rationale for our final decisions regarding these other 
changes to the Mineral Wool Production NESHAP?
    There was no information in the public comments that affected the 
rationale for these provisions that was presented in the various 
proposals. Therefore, we are finalizing the proposed provisions 
regarding electronic reporting; testing methods and frequency; 
definitions and revisions to the General Provision applicability table.

V. What is included in the Final Wool Fiberglass Manufacturing Rule for 
major sources?

    This action finalizes the EPA's determinations pursuant to the RTR 
provisions of CAA section 112 for the Wool Fiberglass Manufacturing 
source category and amends the Wool Fiberglass Manufacturing NESHAP 
based on those determinations. This action also finalizes other changes 
to the NESHAP (e.g., compliance dates) as discussed in section V.F of 
this preamble. In addition, we are finalizing the emission limits for 
major sources in the Wool Fiberglass Manufacturing source category as 
shown in Table 3 of this preamble.

Table 3--Emission Limits for Wool Fiberglass Manufacturing Major Sources
                     [lb pollutant/ton glass pulled]
------------------------------------------------------------------------
              Process                        HAP          Emission limit
------------------------------------------------------------------------
Existing Flame Attenuation Lines..  Formaldehyde........             5.6
                                    Phenol..............             1.4
                                    Methanol............            0.50
New Flame Attenuation Lines.......  Formaldehyde........             2.6
                                    Phenol..............            0.44
                                    Methanol............            0.35
Existing and New Furnaces.........  PM..................            0.33
Existing and New Gas-Fired          Chromium compounds..         0.00025
 Furnaces.
------------------------------------------------------------------------

[[Page 45292]]

A. What are the final rule amendments based on the risk review for the 
Wool Fiberglass Manufacturing (major sources) source category?

    Pursuant to CAA section 112(f)(2), we are finalizing emission 
limits for chromium emissions from gas-fired glass-melting furnaces of 
0.00025 pounds of total chromium per ton of glass pulled to provide an 
ample margin of safety to protect public health. We are also requiring 
that facilities establish the materials mix, including the percentages 
of raw materials and cullet, used in gas-fired glass-melting furnaces 
during the performance test conducted to demonstrate compliance with 
the chromium emission limit. We are requiring that the percentage of 
cullet in the material mix be continually maintained at or below the 
level established during the most recent performance test showing 
compliance with the standard.
    We note that although we have adopted these same standards, under 
both CAA sections 112(f)(2) and 112(d)(6), these standards rest on 
independent statutory authorities and independent rationales. 
Consequently, these standards remain independent and legally severable.

B. What are the final rule amendments based on the technology review 
for the Wool Fiberglass Manufacturing (major sources) source category?

    We determined that there are developments in practices, processes, 
and control technologies that warrant revisions to the MACT standards 
for this source category. Therefore, to satisfy the requirements of CAA 
section 112(d)(6), we are revising the existing MACT standards to 
include an emission limit for glass-melting furnaces of 0.33 pounds of 
PM per ton of glass pulled as we proposed in April 2013. In this 
action, we are also revising the proposed chromium emission limit for 
gas-fired glass-melting furnaces from 0.00006 to 0.00025 pounds of 
total chromium per ton of glass pulled, based on our re-assessment of 
emissions data for newly-rebuilt gas-fired glass-melting furnaces.
    We note that although we have adopted the total chromium compounds 
standards under both CAA sections 112(f)(2) and 112(d)(6), these 
standards rest on independent statutory authorities and independent 
rationales. Consequently, these standards remain independent and 
legally severable.

C. What are the final rule amendments pursuant to CAA sections 
112(d)(2) and (3) for the Wool Fiberglass Manufacturing (major sources) 
source category?

    This action finalizes the HAP-specific limits proposed in November 
2014 that we developed under CAA sections 112(d)(2) and (3) as a result 
of removing the use of formaldehyde as a surrogate for methanol and 
phenol on FA lines. We are also eliminating the subcategories for FA 
lines because the technical bases for distinguishing the subcategories 
when the original rule was developed no longer exist and we are 
promulgating emission limits at the MACT floor level for formaldehyde, 
methanol, and phenol.
    As explained in section V.H of this preamble, we are not, at this 
time, finalizing limits under CAA sections 112(d)(2) and (3) for RS 
lines.

D. What are the final rule amendments pursuant to CAA section 112(h) 
for the Wool Fiberglass Manufacturing (major sources) source category?

    This action finalizes the work practice standards for HCl and HF 
emissions from glass-melting furnaces at wool fiberglass manufacturing 
facilities developed under CAA section 112(h) as proposed in November 
2014 (79 FR 68023). These amendments to the Wool Fiberglass 
Manufacturing NESHAP are consistent with the amendments discussed in 
the November 2014 supplemental proposal.

E. What are the final rule amendments for the Wool Fiberglass 
Manufacturing (major sources) source category addressing emissions 
during periods of startup and shutdown?

    We are finalizing, as proposed, changes to the Wool Fiberglass 
Manufacturing NESHAP to eliminate the SSM exemption. Consistent with 
Sierra Club v. EPA, 551 F. 3d 1019 (D.C. Cir. 2008), the EPA has 
established work practice standards in this rule that apply during 
startup and shutdown periods. We are revising Table 1 to subpart NNN of 
part 63 (General Provisions applicability table) to change several 
references related to requirements that apply during periods of SSM. We 
also eliminated or revised certain recordkeeping and reporting 
requirements related to the eliminated SSM exemption. We are specifying 
that items of equipment that are required or utilized for compliance 
with 40 CFR part 63, subpart NNN must be operated during startup and 
shutdown. We are finalizing the specifications designating when startup 
and shutdown begins and recordkeeping requirements for demonstrating 
compliance during startup and shutdown periods.
    We determined that facilities in this source category can meet the 
applicable work practice standards by following the startup and 
shutdown procedures that we identified as representative of the 
procedures employed by the best performing units during periods of 
startup and shutdown.
    Gas-fired furnaces use an electrostatic precipitator (ESP) to 
control emissions during normal operations. The best performing gas-
fired furnaces route emissions during startup and shutdown to the 
control device. We note that operators of gas-fired furnaces that 
formerly turned off the controls during startup or shutdown would no 
longer be allowed to do so.
    Electric furnaces use baghouses to control emissions during normal 
operations. Until the crust is formed on top of the molten glass (and 
startup ends) the temperature of the gases that would be routed to the 
baghouse would cause the bags to catch fire. The best performing 
electric furnaces use only cullet (which emits PM at extremely low 
levels when melted) and clean fuels (natural gas, which does not emit 
PM when combusted) during startup and shutdown in order to minimize PM 
emissions during these periods.

F. What other changes have been made to the Wool Fiberglass 
Manufacturing NESHAP (major sources)?

    We are finalizing, as proposed, the addition of EPA Method 29 for 
measuring the concentrations of chromium. We are finalizing the 
requirement, as proposed, to maintain the filter temperature at 248 
 25 [deg]F when using Method 5 to measure PM emissions from 
furnaces. We are also amending the NESHAP to allow owners or operators 
to measure PM emissions from furnaces using either EPA Method 5 or 
Method 29.
    We are finalizing, as proposed, the addition of EPA Method 318 as 
an alternative test method for measuring the concentration of phenol 
and methanol and EPA Method 308 as an alternative test method for 
measuring the concentration of methanol. We are finalizing, as proposed 
in the 2013 supplemental proposal (78 FR 22402), the replacement of a 
minimum sampling time of 1 hour with the specification to collect 10 
spectra when using EPA Method 318. When using Method 316 to measure 
formaldehyde, we are finalizing, as proposed, the requirement to 
collect a minimum sampling volume of 2 dry standard cubic meters 
(dscm); however, we are not finalizing the

[[Page 45293]]

proposed minimum sampling run time of 2 hours. We are also finalizing 
editorial changes to the performance testing and compliance procedures 
to specify formaldehyde, methanol, phenol (rather than the surrogate, 
formaldehyde), chromium, HCl, and HF. Additionally, for existing 
sources we are finalizing, as proposed, the requirement to conduct 
performance tests to demonstrate compliance with the chromium emission 
limit for furnaces no later than July 31, 2017 and annually thereafter; 
to demonstrate compliance with the PM emission limit for furnaces no 
later than July 31, 2017 and every 5 years thereafter; and to 
demonstrate compliance with the phenol, formaldehyde and methanol 
emission limits for FA lines no later than July 31, 2017 and every 5 
years thereafter.
    We are finalizing the requirement for new sources to comply with 
the emission limits on July 29, 2015, or upon the initial startup, 
whichever is later, and to conduct performance tests to demonstrate 
compliance with the emission limits for furnaces and FA lines no later 
than 180 days after the applicable compliance date. Following the 
initial test to demonstrate compliance with the chromium emission 
limit, owners or operators must test for chromium emissions annually. 
For all other pollutants, owners or operators must conduct performance 
tests every 5 years after the initial test to demonstrate compliance 
with the emissions limits. Table 4 of this preamble summarizes the 
compliance test schedule for major and area sources.

                Table 4--Wool Fiberglass Manufacturing Compliance Test Schedule for Major Sources
----------------------------------------------------------------------------------------------------------------
                                                                Initial test dates
             Process                 Pollutant(s)    ---------------------------------------- Subsequent testing
                                                       Existing sources       New sources          frequency
----------------------------------------------------------------------------------------------------------------
FA Line.........................  Phenol              2 years after       Within 180 days     Every 5 years
                                   Formaldehyde        publication of      after publication   thereafter.
                                   Methanol.           the final rule      in the Federal
                                                       amendments in the   Register, or 180
                                                       Federal Register.   days after
                                                                           initial startup,
                                                                           whichever is
                                                                           later.
All Furnace Types...............  PM
Gas-fired Furnace...............  Chromium compounds                                          Annually
                                                                                               thereafter.
----------------------------------------------------------------------------------------------------------------

    We are finalizing, as proposed, the clarification that 40 CFR part 
63, subpart NNN applies to FA lines, regardless of what products are 
manufactured on the FA line.
    In this action, we are finalizing, as proposed, definitions for 
``gas-fired glass-melting furnace'' and ``incinerator.'' We are also 
revising the definition of ``new source'' and the trigger date for the 
requirement to submit notifications of intent to construct/reconstruct 
an affected source to reflect the date of the initial RTR proposal 
(November 25, 2011).
    We are finalizing, as proposed, the monitoring requirement for 
furnaces and FA lines to provide flexibility in establishing an 
appropriate monitoring parameter.
    We are also making minor corrections to the citations in Table 1 
(part 63 General Provision applicability table) to reflect the final 
amendments in this action, and the revisions that have been made to the 
General Provisions since 1999.

G. What are the effective and compliance dates of the standards?

    The revisions to the MACT standards for the Wool Fiberglass 
Manufacturing source category being promulgated in this action are 
effective on July 29, 2015. The compliance date for existing sources is 
July 31, 2017. New sources must comply with the all of the standards 
immediately upon the effective date of the standard, July 29, 2015, or 
upon initial startup, whichever is later.
    The effective and compliance dates finalized in this action are 
consistent with the dates we presented in the 2014 supplemental 
proposal.

H. What is the status of the Wool Fiberglass Manufacturing MACT 
standard amendments under CAA sections 112(d)(2) and (3) for RS 
Manufacturing Lines?

    We are not finalizing the formaldehyde, methanol, and phenol 
standards under CAA sections 112(d)(2) and (3) for RS manufacturing 
lines in this final action. On November 25, 2011 (76 FR 72791), we 
proposed to discontinue use of formaldehyde as a surrogate for phenol 
and methanol and we proposed formaldehyde, methanol and phenol emission 
limits for RS and FA lines. On April 15, 2013 (72 FR 22387), we 
proposed revised emission limits for RS lines based on clarification of 
test data received from the industry during the comment period. We 
explained that since the 1999 promulgation of the MACT standards, many 
companies had discontinued the use of formaldehyde. However, they did 
not distinguish between the bonded lines that still used formaldehyde 
and those that did not. We had, therefore, included some data for HAP-
free lines along with the data for lines still using formaldehyde when 
we developed the emission limits proposed in the November 2011 proposal 
(78 FR 22387). In the November 2014 supplemental proposal (79 FR 
68203), we also proposed revised formaldehyde, methanol, and phenol 
emission limits for new RS lines as a result of our updated approach 
for evaluating limited datasets (79 FR 68023-24).
    The EPA is not finalizing these proposed CAA sections 112(d)(2) and 
(3) standards in this action because we believe the data that we relied 
on in proposing these standards are not sufficiently related to current 
operations or emissions from RS bonded lines. The emissions and process 
data available to EPA were collected beginning in 2003. As previously 
explained, since that time, sources have phased out the use of a 
phenol/formaldehyde binder from approximately 95 percent of the lines 
on which it was previously used. We have also found out that sources 
often can no longer either identify the products that were tested or on 
the lines on which those products had been manufactured. Moreover, when 
sources can identify the products that were tested, those products are 
now produced using a HAP-free binder, and the product lines that now 
operate using a phenol/formaldehyde binder do not bear similarity in 
size, end use, production rate or loss on ignition (LOI) percent to the 
tested product line. As a result, the data no longer represent current 
industry conditions, most notably the significant reduction in the use 
of phenol/formaldehyde binders in wool fiberglass manufacturing. 
Consequently, we have issued a CAA section 114 ICR to wool fiberglass 
facilities to obtain updated formaldehyde, methanol, and

[[Page 45294]]

phenol emissions and process data for RS manufacturing lines.

I. What are the requirements for submission of performance test data to 
the EPA for the Wool Fiberglass Manufacturing NESHAP?

    The requirements for electronic reporting of performance test data 
for wool fiberglass manufacturing major sources are the same as the 
requirements for the mineral wool production source category. See 
section III.G of this preamble for a description of the requirements.

VI. What is the rationale for our final decisions and amendments for 
the Wool Fiberglass Manufacturing source category (major sources)?

    For each issue, this section provides a description of what we 
proposed and what we are finalizing for the issue, the EPA's rationale 
for the final decisions and amendments and a summary of key comments 
and responses. For all comments not discussed in this preamble, comment 
summaries and the EPA's responses can be found in the comment summary 
and response document available in Docket ID No. EPA-HQ-OAR-2010-1042.

A. Residual Risk Review for the Wool Fiberglass Manufacturing Source 
Category (Major Sources)

1. What did we propose pursuant to CAA section 112(f) for the Wool 
Fiberglass Manufacturing source category (major sources)?
    Pursuant to CAA section 112(f)(2), we conducted a residual risk 
assessment and presented the results of this assessment, along with our 
proposed decisions regarding risk acceptability and ample margin of 
safety, in the November 2011 proposed rule (76 FR 72801). Based on the 
inhalation risk assessment, we estimated that the MIR could be as high 
as 40-in-1 million due to actual emissions and up to 60-in-1 million 
due to MACT-allowable emissions, mainly due to formaldehyde and 
hexavalent chromium emissions. We stated that the risk levels due to 
actual and MACT-allowable emissions were acceptable; however, we 
proposed an emission limit for total chromium (0.00006 pounds per ton 
of glass pulled) in order to provide an ample margin of safety to 
protect public health.
    In the April 2013 supplemental proposal, we revised the draft risk 
assessment to reflect new emissions data for hexavalent chromium that 
we collected from all glass-melting furnaces available for testing in 
response to our October 28, 2011, CAA section 114 ICR. These revisions 
reduced our estimate of risk from actual emissions when compared to the 
risk assessment conducted for the November 2011 proposal. The risk from 
wool fiberglass manufacturing was driven by formaldehyde and hexavalent 
chromium. The MIR for actual baseline emissions decreased from 40-in-1-
million to 20-in-1 million (formaldehyde), with the acute noncancer HQ 
remaining at 30 for the REL and at 2 for the AEGL-1 (formaldehyde). The 
maximum chronic non-cancer TOSHI value based on actual emissions 
remained at 0.2 with emissions of formaldehyde dominating those 
impacts, indicating no significant potential for chronic noncancer 
impacts.
    In the November 2014 supplemental proposal, we presented the 
revised draft risk assessment to reflect updates to the model and model 
libraries and also retained the proposed emission limits for chromium 
compounds for existing and new gas-fired glass-melting furnaces. These 
revisions did not significantly change our estimate of risk from actual 
emissions when compared to the risk assessment conducted for the April 
2013 supplemental proposal (79 FR 68020). The risk from wool fiberglass 
manufacturing was driven by formaldehyde and hexavalent chromium and 
continued to be well within a level we consider to be acceptable. The 
MIR for actual baseline emissions remained 20-in-1 million 
(formaldehyde), with the acute noncancer HQ remaining at 30 for the REL 
and decreased from 2 to 1 for the AEGL-1 (formaldehyde). The maximum 
chronic non-cancer TOSHI value based on actual emissions decreased from 
0.2 to 0.1 with emissions of formaldehyde dominating those impacts, 
indicating no significant potential for chronic noncancer impacts. 
Overall, we considered the risk to be acceptable.
    Based on information provided by the industry, 95 percent of the RS 
lines no longer use phenol-formaldehyde binders and are no longer major 
sources. However, this phase out is not reflected in the facility file 
data on which the risk assessment was based. Throughout the wool 
fiberglass manufacturing industry, these binders continued to be phased 
out as this rule was developed. The risk analysis we conducted for the 
Wool Fiberglass Manufacturing source category overstates the risk 
because of the continuing phase out. Therefore, we believe the risks 
from wool fiberglass manufacturing from actual emissions are lower than 
the risks we estimated.
2. How did the risk review change for the Wool Fiberglass Manufacturing 
source category (major sources)?
    The baseline risk assessment has not changed since the November 
2014 supplemental proposal. The MIR based on actual emissions remains 
at 20-in-1 million with the acute noncancer HQ remaining at 30 for the 
REL and 1 for the AEGL-1 (formaldehyde). The maximum chronic non-cancer 
TOSHI value based on actual emissions is 0.1 with emissions of 
formaldehyde dominating those impacts, indicating no significant 
potential for chronic noncancer impacts.
    The MIR based on MACT-allowable emissions could be as high as 60-
in-1 million, which we believe to be a conservative estimate based on 
four factors: (1) At one time, there were at least 60 RS lines in the 
industry, (2) industry has stated that 95 percent of RS lines no longer 
use formaldehyde as a binder, (3) Industry has stated that there are 
only 5 RS lines left that use a phenol/formaldehyde binder, and (4) 
Title V permit records indicate that 20 out of a total of 30 facilities 
have completely phased out their use of formaldehyde as a raw material 
throughout the facility.
    We conducted a new assessment of the risks remaining after 
implementation of these final rule revisions. The revised assessment of 
post-control risks reflects the adjustment of the chromium compounds 
emission limit and the EPA's deferral of setting standards for 
formaldehyde, methanol and phenol from RS lines. Specifically, the risk 
assessment takes into account the change in the chromium compounds 
emission limit for gas-fired glass-melting furnaces from 0.00006 pounds 
of chromium per ton of glass pulled to 0.00025 pounds of chromium per 
ton of glass pulled, the emission limits for formaldehyde at new and 
existing FA lines (2.6 pounds per ton and 5.6 pounds per ton, 
respectively) and the current emission estimates for formaldehyde, 
methanol and phenol from RS lines. The MIR for cancer after 
implementation of the RTR could be up to 60-in-1 million (equal to the 
current risk estimates for allowables) but, as discussed above, this is 
a conservative, upper-end estimate. Consequently, we believe risks are 
significantly lower than estimated and the standards provide an ample 
margin of safety.
    Emissions of chromium compounds are a secondary risk driver to 
formaldehyde, and the risk is 7-in-1 million based on current actual 
emissions. It is important to note that,

[[Page 45295]]

even though risks are acceptable, the health risks from hexavalent 
chromium emissions from wool fiberglass manufacturing facilities could 
be much higher in the future without a chromium compounds emission 
limit. To capture this scenario, we conducted an auxiliary risk 
analysis in which we assumed all wool fiberglass furnaces emitted 
hexavalent chromium at the same rate as the reasonable highest-emitting 
furnace. The results of the auxiliary risk analysis showed that, in the 
absence of a chromium emission limit and with furnaces emitting at the 
assumed emission rate, risk at four facilities is expected to increase 
over time to greater than 100-in-1 million, due to increasing chromium 
emissions occurring with furnace age. Therefore, we determined that the 
chromium emission limit in the final rule, which will limit the MIR 
cancer risk from hexavalent chromium emissions from this category to no 
higher than 3-in-1 million, is necessary to provide an ample margin of 
safety.
    Regarding chromium compounds, as discussed above, we received 
comments on the proposed chromium compounds limit that indicated that a 
newly-rebuilt furnace, which we believe is the likely compliance 
technology, may not be able to demonstrate compliance with the proposed 
emission limit. The comment was based on one specific example from the 
2012 test data that showed a 1-year old gas-fired glass-melting furnace 
emitting approximately 0.0002 pounds chromium per ton of glass. We re-
evaluated the proposed chromium compounds limit in light of information 
on this technology, and based on the data available, we have revised 
the chromium compounds limit and are now finalizing an emissions limit 
of 0.00025 pounds per ton of glass pulled for gas-fired glass-melting 
furnaces. We conducted an assessment of the risk attributable to all 
HAP for each facility and determined that increasing the chromium 
compound emission limit from 0.00006 to 0.00025 pounds total chromium 
per ton of glass pulled has a minimal effect on the post-RTR risks 
because these risks are largely driven by formaldehyde emissions. 
Specifically, at the chromium compounds emission limit of 0.00025 
pounds total chromium per ton of glass pulled, the MIR due to only 
chromium emissions for the source category is 3-in-1 million.
    The results of the risk assessment are presented in more detail in 
the final residual risk memorandum titled ``Residual Risk Assessment 
for the Mineral Wool Production and Wool Fiberglass Manufacturing 
Source Categories in Support of the June 2015 Final Rule,'' which can 
be found in Docket ID No. EPA-HQ-OAR-2010-1042.
3. What key comments did we receive on the risk review for Wool 
Fiberglass Manufacturing (major sources), and what are our responses?
    We received comments in support of and against our proposed 
determination of risk acceptability, ample margin of safety analysis, 
and requirement for additional control. A summary of these comments and 
our responses can be found in the comment summary and response document 
available in the docket for this action (EPA-HQ-OAR-2010-1042). The 
following is a summary of the key comments received regarding the risk 
assessment for the Wool Fiberglass Manufacturing source category and 
our responses to these comments. Additional comments on the risk 
assessment and our responses can be found in the comment summary and 
response document available in the docket for this action (EPA-HQ-OAR-
2010-1042).
    Comment: One commenter stated that the EPA should find the acute 
health risk from wool fiberglass manufacturing facilities to be 
unacceptable. The commenter noted that the EPA's assessment in the 
November 2011 proposal found an acute risk of 30 for the Wool 
Fiberglass Manufacturing source category and argued that the EPA should 
find the health risk to be unacceptable under CAA section 112(f)(2) 
based on this acute risk.
    The commenter stated that the EPA has a presumption that an HQ 
below 1 is safe, that the EPA has stated that a HQ less than or equal 
to 1 indicates that adverse noncancer effects are not likely to occur, 
and that exposure below that threshold level is safe. The commenter 
added that the EPA did not adequately explain why the formaldehyde 
risks were found to be acceptable although they are 30 times higher 
than the threshold.
    The commenter asserted that, by applying the outdated integrated 
risk information system (IRIS) dose-response values in determining 
formaldehyde inhalation exposure risk, the EPA is not basing the 
proposed rule on the best available science. The commenter urged the 
EPA to revise the proposed rule to accurately convey the best available 
science and a weight-of-evidence approach in compliance with the 
Information Quality Act (IQA) Guidelines and Executive Order 13563. In 
particular, the commenter argued that the EPA should reject the 1991 
IRIS dose-response value and incorporate the Chemical Industry 
Institute of Toxicology (CIIT, 1999) cancer dose-response value for 
formaldehyde.
    Response: As discussed in sections V.A and VI.A of this preamble, 
we revised the risk assessment for wool fiberglass facilities for the 
November 2014 supplemental proposal. For wool fiberglass facilities, 
the MIR for actual baseline emissions remained 20-in-1 million 
(formaldehyde), with the acute noncancer HQ remaining at 30 for the REL 
and decreased from 2 to 1 for the AEGL-1 (formaldehyde). The maximum 
chronic non-cancer TOSHI value based on actual emissions decreased from 
0.2 to 0.1 with emissions of formaldehyde dominating those impacts, 
indicating no significant potential for chronic noncancer impacts. We 
found that the risks were acceptable.
    We note that the acute risks are based on an REL value, which is 
defined as ``the concentration level at or below which no adverse 
health effects are anticipated for specified exposure duration.'' 
Moreover, we note that the acute risk assessment is a worst-case 
assessment. For example, the acute assessment assumes worst-case 
meteorology, peak emissions and an individual being located at the site 
of maximum concentration for an hour. Taken together, the EPA does not 
believe that in all RTR reviews, HQ values must be less than or equal 
to 1. Rather, the EPA finds that acute risks must be judged on a case-
by-case basis in the context of all the available health evidence and 
risk analyses.
    To better characterize the potential health risks associated with 
estimated acute exposures to HAP, and in response to a key 
recommendation from the Science Advisory Board's (SAB) peer review of 
the EPA's RTR risk assessment methodologies,\6\ we generally examine a 
wider range of available acute health metrics (e.g., RELs, AEGLs) than 
we do for our chronic risk assessments. This is in response to the 
SAB's acknowledgement that there are generally more data gaps and 
inconsistencies in acute reference values than there are in chronic 
reference values. In some cases, when Reference Value Arrays \7\ for 
HAP have been developed, we consider additional acute values (i.e., 
occupational and

[[Page 45296]]

international values) to provide a more complete risk characterization. 
The EPA uses AEGL and Emergency Response Planning Guidelines (ERPG) 
values (when available) in conjunction with REL values (again, when 
available) to characterize potential acute health risks. However, it is 
often the case that HAP do not have all of these acute reference 
benchmark values. In these instances, the EPA describes the potential 
acute health risk in relation to the acute health values that are 
available. Importantly, when interpreting the results, we are careful 
to identify the benchmark being used and the health implications 
associated with any specific benchmark being exceeded. By definition, 
the acute California reference exposure level (CA-REL) represents a 
health-protective level of exposure, with no risk anticipated below 
those levels, even for repeated exposures; however, the health risk 
from higher-level exposures is unknown. Therefore, when a CA-REL is 
exceeded and an AEGL-1 or ERPG-1 level is available (i.e., levels at 
which mild effects are anticipated in the general public for a single 
exposure), we have used them as a second comparative measure. 
Historically, comparisons of the estimated maximum off-site 1-hour 
exposure levels have not been typically made to occupational levels for 
the purpose of characterizing public health risks in RTR assessments. 
This is because occupational ceiling values are not generally 
considered protective for the general public since they are designed to 
protect the worker population (presumed healthy adults) for short 
duration (i.e., less than 15 minute) increases in exposure. As a 
result, for most chemicals, the 15-minute occupational ceiling values 
are set at levels higher than a 1-hour AEGL-1, making comparisons to 
them irrelevant unless the AEGL-1 or ERPG-1 levels are exceeded. Such 
is not the case when comparing the available acute inhalation health 
effect reference values for formaldehyde.\8\
---------------------------------------------------------------------------

    \6\ The SAB peer review of RTR Risk Assessment Methodologies is 
available at: http://yosemite.epa.gov/sab/sabproduct.nsf/
4AB3966E263D943A8525771F00668381/$File/EPA-SAB-10-007-unsigned.pdf.
    \7\ U.S. EPA. (2009) Chapter 2.9 Chemical Specific Reference 
Values for Formaldehyde in Graphical Arrays of Chemical-Specific 
Health Effect Reference Values for Inhalation Exposures (Final 
Report). U.S. EPA, Washington, DC, EPA/600/R-09/061, and available 
on-line at: http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=211003.
    \8\ U.S. EPA. (2009) Chapter 2.9 Chemical Specific Reference 
Values for Formaldehyde in Graphical Arrays of Chemical-Specific 
Health Effect Reference Values for Inhalation Exposures (Final 
Report). U.S. EPA, Washington, DC, EPA/600/R-09/061, and available 
on-line at: http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=211003.
---------------------------------------------------------------------------

    Thus, while this means we cannot rule out the potential for acute 
concerns due to formaldehyde emissions from these facilities, we note 
that the worst-case acute HQs are based on conservative assumptions 
(e.g., worst-case meteorology coinciding with peak short-term 1-hour 
emissions from each emission point, with a person located at the point 
of maximum concentration during that hour). We also note that, as 
stated earlier, the emissions estimates for formaldehyde are expected 
to be an overestimate of emissions, further supporting our 
determination that acute risks are not a significant concern for the 
wool fiberglass source category.
    Comment: One commenter stated that AEGLs or ERPGs were developed 
for accidental release emergency planning and are not appropriate for 
assessing daily human exposure to toxic air pollutants because they do 
not include adequate safety and uncertainty factors. The commenter 
stated that they are not meant to evaluate the acute impacts from 
routine emissions that occur over the life of a facility and cannot be 
relied upon to protect the public from the adverse effects of exposure 
to toxic air pollutants. The commenter concluded that their use is not 
appropriate in risk assessments and urged the EPA to increase its 
reliance on the California RELs to address acute exposures in the 
residual risk assessments.
    Response: The EPA does not rely exclusively upon AEGL or ERPG 
values for assessment of acute exposures. Rather, the EPA's approach is 
to consider various acute health effect reference values (see the 
preamble to the November 2011 proposal (76 FR 72781)), including the 
California REL, in assessing the potential for risks from acute 
exposures. To better characterize the potential health risks associated 
with estimated acute exposures to HAP, and in response to a key 
recommendation from the SAB's peer review of the EPA's RTR risk 
assessment methodologies, we generally examine a wider range of 
available acute health metrics (e.g., RELs, AEGLs) than we do for our 
chronic risk assessments. This is in response to the SAB's 
acknowledgement that there are generally more data gaps and 
inconsistencies in acute reference values than there are in chronic 
reference values. In some cases, when Reference Value Arrays for HAP 
have been developed, we consider additional acute values (i.e., 
occupational and international values) to provide a more complete risk 
characterization. As discussed in the preamble to the November 2011 
proposal, the exposure guidelines the EPA considers depends on which 
exposure guidelines are available for the various HAP emitted. The EPA 
uses AEGL and ERPG values (when available) in conjunction with REL 
values (when available) to characterize potential acute health risks. 
However, it is often the case that HAP do not have all of these acute 
reference benchmark values. In these instances, the EPA describes the 
potential acute health risk in relation to the acute health values that 
are available. Importantly, when interpreting the results, we are 
careful to identify the benchmark being used and the health 
implications associated with any specific benchmark being exceeded.
    Comment: According to one commenter, the EPA`s multipathway risk 
assessment fell short because the EPA did not use ``allowable'' 
emissions for this assessment and the proposed rule shows multipathway 
risks that are 60 times greater than the EPA's threshold. The commenter 
stated that the EPA acknowledged in its 2014 risk assessment that the 
emissions allowed by the standard may be up to 3 times greater than 
actual emissions for phenol, methanol, and formaldehyde, such that the 
HQ of 30 could be 3 times higher based on allowable emissions. The 
commenter stated that by using actual emissions, the EPA's analysis is 
likely to be an underestimate of the health risks from multipathway 
routes of exposure. The commenter supports the EPA's use of 
``allowable'' as well as ``actual'' emissions to assess inhalation 
risk.
    Response: Consistent with previous risk assessments, the EPA 
considers both allowable and actual emissions in assessing chronic 
risks under CAA section 112(f)(2) (See, e.g., National Emission 
Standards for Coke Oven Batteries (70 FR 19998-19999, April 15, 2005); 
proposed and final National Emission Standards for Organic Hazardous 
Air Pollutants from the Synthetic Organic Chemical Manufacturing 
Industry (71 FR 34428, June 14, 2006, and 71 FR 76603, December 21, 
2006). This approach is both reasonable and consistent with the 
flexibility inherent in the Benzene NESHAP framework for assessing 
acceptable risk and ample margin of safety, as developed in the Benzene 
NESHAP (54 FR 38044, September 14, 1989). As a general matter, modeling 
allowable emission levels is inherently reasonable since this reflects 
the maximum level sources could emit and still comply with national 
emission standards. But, it is also reasonable to consider actual 
emissions, where such data are available, in the acceptable risk and 
ample margin of safety analyses. See National Emission Standards for 
Coke Oven Batteries (70 FR 19992, 19998, April 15, 2005). The commenter 
claims that limiting our review to actual emissions would be 
inconsistent with the applicability section of Part 63 rules. As 
explained, however, we did not limit our review to actual emissions.
    The commenter also urged the agency to rely on allowable emissions 
for the purpose of our acute assessment. The

[[Page 45297]]

use of allowable emissions was not considered due to the conservative 
assumptions used to gauge worst-case potential acute health effects. 
The conservative assumptions built into the acute health risk screening 
analysis include: (1) Use of peak 1-hour emissions that are, on 
average, 10 times the annual average 1-hour emission rates; (2) that 
all emission points experience peak emissions concurrently; (3) worst-
case meteorology (from 1 year of local meteorology); and (4) that a 
person is located downwind at the point of maximum impact during this 
same 1-hour period. Thus, performing an acute screen based on allowable 
emissions would be overly conservative and at best, of questionable 
utility to decision makers.
    Comment: Two commenters stated that the EPA does not have authority 
to consider ``total facility'' emissions in conducting the residual 
risk assessments for a given source category. The commenter argued that 
it would be impossible for the EPA to fulfill its unambiguous 
obligation for CAA section 112(f) standards to protect public health 
with an ample margin of safety in cases where facilities contain 
sources in a category where the 8-year deadline for conducting the CAA 
section 112(f) risk review precedes the adoption of MACT standards for 
other sources at the facilities. One commenter added that CAA section 
112(f)(2)(A) requires EPA to promulgate standards on a source category 
basis. Another commenter continued that this provision unambiguously 
requires the CAA section 112(f) risk assessment to be focused 
exclusively on ``emissions from a source in the category or 
subcategory,'' asserting that the EPA does not have authority to 
consider emissions from any sources other than those in the source 
category or subcategory under review at that time.
    Response: We disagree that examining facility-wide risk in a risk 
assessment conducted under CAA section 112(f) exceeds the EPA's 
authority. The development of facility-wide risk estimates provides 
additional information about the potential cumulative risks in the 
vicinity of the RTR sources, as one means of informing potential risk-
based decisions about the RTR source category in question. While we 
recognize that, because these risk estimates were derived from 
facility-wide emissions estimates which have not generally been 
subjected to the same level of engineering review as the source 
category emission estimates, they may be less certain than our risk 
estimates for the source category in question, they remain important 
for providing context as long as their uncertainty is taken into 
consideration.
    Section 112(f)(2) of the CAA expressly preserves our use of the 
two-step process for developing standards to address residual risk and 
interpret ``acceptable risk'' and ``ample margin of safety'' as 
developed in the Benzene NESHAP (54 FR 38044, September 14, 1989). In 
the Benzene NESHAP, the EPA rejected approaches that would have 
mandated consideration of background levels of pollution in assessing 
the acceptability of risk, concluding that ``. . . comparison of 
acceptable risk should not be associated with levels in polluted urban 
air. With respect to considering other sources of risk from benzene 
exposure and determining the acceptable risk level for all exposures to 
benzene, the EPA considers this inappropriate because only the risk 
associated with the emissions under consideration are relevant to the 
regulation being established and, consequently, the decision being 
made.'' (54 FR 38044, 38061, September 14, 1989).
    Although not appropriate for consideration in the determination of 
acceptable risk, we note that background risks or contributions to risk 
from sources outside the source category under review could be one of 
the relevant factors considered in the ample margin of safety 
determination, along with cost and economic factors, technological 
feasibility, and other factors. Background risks and contributions to 
risk from sources outside the facilities under review were not 
considered in the ample margin of safety determination for this source 
category, mainly because of the significant uncertainties associated 
with emissions estimates for such sources. Our approach here is 
consistent with the approach we took regarding this issue in the 
Hazardous Organic NESHAP (HON) RTR (71 FR 76603, December 21, 2006), 
which the court upheld in the face of claims that the EPA had not 
adequately considered background.
    In our November 2011 proposal, we explained that for these source 
categories, there are no other significant HAP emissions sources 
present at wool fiberglass manufacturing and mineral wool production 
facilities beyond those included in the source category. We also 
explained that all significant HAP sources have been included in the 
source category risk analysis. We therefore concluded that the 
facility-wide risk is essentially the same as the source category risk 
and that no separate facility-wide analysis was necessary (76 FR 72783, 
November 25, 2011). Our evaluation of facility-wide risks did not 
change our decisions under CAA section 112(f)(2) about acceptability 
and ample margin of safety of the risks associated with the wool 
fiberglass source categories.
4. What is the rationale for our final approach and final decisions for 
the risk review for the Wool Fiberglass Manufacturing source category 
(major sources)?
    For the Wool Fiberglass Manufacturing source category, we have 
determined that the current MACT standards reduce risk to an acceptable 
level. We have further evaluated the cost, emissions reductions, energy 
implications and cost effectiveness of the total chromium compounds 
emission limits being promulgated in this final rule and have 
determined that they are cost effective, technically feasible and will 
provide an ample margin of safety to protect public health and prevent 
adverse environmental effects.
    For chromium emissions, we are finalizing the emission limit of 
0.00025 pounds total chromium per ton of glass pulled for gas-fired 
glass-melting furnaces, under CAA section 112(f)(2). This is based on 
our assessment of emissions from newly-rebuilt gas-fired glass-melting 
furnaces. Because commenters provided new information indicating that 
cullet use is tied to increasing chromium emissions from gas-fired 
glass-melting furnaces, we are also requiring that facilities establish 
the materials mix, including the percentages of raw materials and 
cullet, used in gas-fired glass-melting furnaces during the performance 
test conducted to demonstrate compliance with the chromium emission 
limit. Affected sources must maintain the percentage of cullet in the 
material mix at or below the level established during the most recent 
performance test showing compliance with the standard. If a gas-fired 
glass-melting furnace uses 100 percent cullet during the most recent 
performance test showing compliance with the standard, then monitoring 
of the cullet use on that furnace is not required until the next annual 
performance test.

[[Page 45298]]

B. Technology Review for the Wool Fiberglass Manufacturing Source 
Category (Major Sources)

1. What did we propose pursuant to CAA section 112(d)(6) for the Wool 
Fiberglass Manufacturing source category (major sources)?
    As discussed in the 2011 proposal (76 FR 72803-72804, 72798), we 
conducted a technology review for FA and RS bonded lines and for 
furnaces that focused on identifying and evaluating developments in 
practices, processes, and control technologies for the emission sources 
in the Wool Fiberglass Manufacturing source category that have occurred 
since the 1999 MACT rules were promulgated. We consulted the EPA's 
RACT/BACT/LAER Clearinghouse to identify potential technology advances 
for processes similar to those covered by the Wool Fiberglass 
Manufacturing NESHAP, as well as the costs, non-air impacts, and energy 
implications associated with the use of these technologies.
    We also requested information from facilities regarding 
developments in practices, processes, or control technologies, and 
conducted site visits, held meetings with industry representatives, and 
reviewed other information sources, such as technical literature, state 
and local permitting agency databases and industry-supported databases. 
For more information, see the ``Technology Review for the Wool 
Fiberglass Manufacturing Source Category Memorandum'' in the docket to 
this rule.
    Subsequent to the November 2011 proposal, we announced that we had 
issued a CAA section 114 ICR to collect emissions data and other 
information on glass-melting furnaces in order to regulate area sources 
in a future action. This resulted in a near complete dataset for 
emissions test data on all wool fiberglass furnaces, with the only 
exceptions being furnaces at facilities that were closed or that were 
shut down at the time of the 2012 testing. The data also indicated that 
three gas-fired glass-melting furnaces had been rebuilt and retested, 
and we also had emissions test data for these three furnaces for the 
years before and after the rebuild.
a. Technology Review for Reduction of PM From Furnaces
    For our technology review under CAA section 112(d)(6), for PM 
emissions from glass-melting furnaces, we identified advances in 
control measures for PM emissions. These included improvements and 
advances in control technology, such as application of ESPs, as well as 
developments in furnace design and the use of high-chromium furnace 
refractories that had been made since promulgation of the 1999 NESHAP.
    Our technology review included glass-melting furnaces at both area 
and major sources. As explained in our April 2013 supplemental 
proposal, the number of area sources is constantly increasing as a 
result of the definition of ``wool fiberglass facility'' in Subpart 
NNN. For example, in 2002, two out of 33 facilities were area sources, 
but by December 2012, 20 facilities were area sources (78 FR 22377). As 
also previously explained, there are no differences between the 
furnaces used at major and area sources (78 FR 22377). Therefore, we 
believed it was appropriate to consider all furnaces in the technology 
review, under CAA section 112(d)(6).
    In our November 2011 proposal, based on the responses to survey 
data regarding the performance of existing control measures, we 
proposed an emission limit of 0.014 pounds of PM per ton of glass 
pulled for glass-melting furnaces, under CAA section 112(d)(6).
    In the April 2013 supplemental proposal, in response to comments we 
received on our November 2011 proposal, we revised the PM limit for 
furnaces to 0.33 pounds per ton of glass pulled in order to be 
consistent with our intentions to set the new limit based on technology 
review.
    We did not propose any further revisions to the proposed PM limit 
in the November 2014 supplemental proposal.
b. Technology Review for Reduction of Chromium From Furnaces
    In our November 2011 proposal, we identified refractories having a 
high content of chromium, and their use in wool fiberglass furnaces, as 
a new development affecting the emissions of chromium compounds from 
sources since promulgation of the 1999 NESHAP. We reviewed the use of 
chromium refractories (as compared to non-chromium refractories), as 
well as other control technologies, such as caustic scrubbers. We 
analyzed the technical feasibility and the estimated impacts (e.g., 
costs, emissions reductions, risk reductions) of applying these 
developments. We then determined, based on impacts and feasibility, 
whether it was necessary to propose amendments to the regulation to 
require any of the identified developments.
    We found that, while the furnaces and control technologies are 
generally the same as those used at promulgation of the MACT standard 
in 1999, there have been some developments in furnace design and 
preference in control equipment. We found that developments in 
refractory technology and in furnace design are inextricably linked. 
Oxyfuel furnaces were not widely used prior to 1999 in the wool 
fiberglass industry, due to a number of factors, especially refractory 
degradation in the wool fiberglass furnace environment. At that time, 
new technology of the oxyfuel furnace constructed using conventional 
refractories of that time (e.g., alumina-silicate, zirconium) limited 
the furnace life to 4 or 5 years. As a result, air-gas and electric 
furnaces predominated in the years prior to 1999.
    With the advent of new refractory technology, new furnace designs 
were constructed that could be expected to last longer. With the 
industry focus upon new furnace designs and technology, the research to 
develop refractories that could withstand high temperatures, thermal 
shock and corrosive materials yielded the development of new types of 
chromium refractory products that could be used for construction of the 
high-temperature oxyfuel furnace.
    As a result, the wool fiberglass industry began a trend toward 
oxyfuel furnaces constructed using high-chromium refractory products, a 
trend that commenters noted is expected to continue into the future. 
This gives rise to increased chromium emissions as a result of both 
wool fiberglass raw material formulation (corrosivity) and associated 
refractory degradation (i.e., furnace wear). We explained the 
mechanisms of chromium emissions at length in our April 2013 
supplemental proposal (78 FR 22379-22382) and in our technology review 
memorandum.
    We therefore found that the development of new types of chromium 
refractories that could and would be used to construct entire gas-fired 
glass-melting furnaces for wool fiberglass manufacturing is a 
development that largely took place after promulgation of the MACT 
standard in 1999. We also proposed a total chromium compounds limit of 
0.00006 pounds per ton of glass pulled for all glass-melting furnaces.
    In the 2013 supplemental proposal, we did not revise the chromium 
emission limit for furnaces; however, we explained that there were two 
general types of furnaces used in this industry: Gas-fired (which 
include both air-gas and oxyfuel furnaces) and electric furnaces (which 
include both steel shell and cold-top electric furnaces). We proposed 
in the April 2013 supplemental proposal to limit the

[[Page 45299]]

applicability of the total chromium compounds emission limit to gas-
fired glass-melting furnaces for two reasons: (1) Electric furnaces do 
not have chromium refractories above the glass melt line, and (2) they 
do not reach the operating temperatures necessary to convert 
significant amounts of trivalent to hexavalent chromium. As a result, 
electric furnaces do not emit significant amounts of chromium 
compounds.
    We did not propose to revise the chromium compounds limit in our 
November 2014 supplemental proposal. However, based on comments 
received on our April 2013 supplemental proposal, we proposed that 
sources would be likely to rebuild the furnace rather than install a 
sodium hydroxide scrubber as previously proposed, due to revisions to 
our cost estimate for this control option.
2. How did the technology review change for the Wool Fiberglass 
Manufacturing source category (major sources)?
    We did not make any changes to the technology review for PM from 
furnaces since the November 2014 supplemental proposal, and we are 
finalizing the previously proposed emission limit for PM, which is 0.33 
lb per ton of glass pulled.
    For chromium compounds, based on the public comments and 
information for glass-melting furnaces received on our November 2014 
supplemental proposal, we believe it is necessary to revise our 
technology review under CAA section 112(d)(6) for gas-fired glass-
melting furnaces in the Wool Fiberglass Manufacturing source category. 
Data collected on gas-fired glass-melting furnaces in 2010 and 2012 
show that three furnaces tested their emissions for chromium in 2010, 
then shut down or repaired, and then retested in 2012 using the same 
test methods and protocols. In each case, chromium emissions were 
reduced by about 2/3 as a result of having rebuilt the furnaces. In two 
of the three cases, the chromium emissions before the repair or rebuild 
were higher than the proposed limit (0.00006 lb/ton of glass). In a 
third case, a furnace that measured 0.0006 lb/ton of glass in 2010 was 
rebuilt and retested for the 2012 ICR. The second test measured 
chromium at 0.0002 lb/ton of glass, a level slightly higher than our 
proposed chromium emission limit.
    While we recognize that the rebuilt furnaces had different designs 
depending on the company's objectives at the particular facility, at 
this time we believe the highest emitting rebuilt furnace was well 
designed for its intended use. This furnace was rebuilt only one year 
before testing, at a cost to the company of between $10-12 million. As 
this is a technology review standard, we consider cost when evaluating 
the technology. We consider it reasonable to evaluate the technology 
based on the emission limit achieved by new furnaces, and we are 
increasing the chromium limit above what was previously proposed to 
account for this new furnace.
    The final chromium limit also prevents operation of another furnace 
that could emit chromium at the reasonable high-end rate of the highest 
emitting furnace, as characterized in section VI of this preamble. 
Finally, we evaluated the cost, using our revised economic analysis, of 
compliance with the final limit and found that these costs are 
reasonable.
    Specifically, we are revising the estimated costs of rebuilding the 
furnace as an option to comply with the chromium limit. We have 
determined, based on the revised costs and data regarding the level of 
chromium emissions that is achieved by rebuilt furnaces, that it is 
necessary, pursuant to CAA section 112(d)(6), to revise the proposed 
emission limit for chromium from gas-fired glass-melting furnaces. We 
are finalizing a limit of 0.00025 pounds chromium compounds per ton of 
glass pulled. This is a higher limit for chromium compounds than 
previously proposed, because data show that this level can be achieved 
by furnaces that are rebuilt, while the previously proposed level was 
shown to be lower than the level supported by the data provided by 
industry. We explain our decision further in the responses to key 
comments below and in the Technology Review Memo for the Wool 
Fiberglass Manufacturing source category, available in the docket to 
the rule.
    We revised the cost estimate for rebuilding a gas-fired glass-
melting furnace; however, we did not revise our finding from our 
technology review that rebuilding the furnace is an effective approach 
for reducing chromium emissions. We also note, from our technology 
review, that other options to reduce chromium from furnaces are 
available to wool fiberglass manufacturers. These include raw material 
substitution and installation of a properly-designed caustic (sodium 
hydroxide) scrubber to the outlet of the dry electrostatic precipitator 
(DESP). These other options are presented in more detail in the 
Economic Analysis, which accompanied the April 2013 supplemental 
proposal.
3. What key comments did we receive on the technology review, and what 
are our responses?
    We received comments in support of and against our proposed 
technology review. The following is a summary of the key comments 
received regarding the technology review for the Wool Fiberglass 
Manufacturing source category and our responses. Additional comments on 
the technology review and responses can be found in the comment summary 
and response document available in the docket for this action (EPA-HQ-
OAR-2010-1042).
    Comment: One commenter stated that the EPA's depiction in the 2011 
proposal (76 FR 72770, November 25, 2011) of high-chromium refractories 
and furnace control technologies as new technology developments is 
inaccurate, as demonstrated by the following evidence: (1) High-
chromium refractories have been used in the wool fiberglass industry 
since the early 1980s; (2) the EPA was aware in 1999 that chromium was 
emitted from wool fiberglass plants, as demonstrated by the following 
statement in its 1999 promulgation preamble ``The hazardous air 
pollutants (HAP) emitted by the facilities covered by this rule include 
compounds of three metals (arsenic, chromium, lead) and three organic 
HAP,'' \9\ although chromium emissions (and all metal HAP) at that time 
were insignificant and PM was chosen as a surrogate for those low 
emissions; and (3) chromium emission reductions have been achieved by 
the industry since initial MACT implementation in 1999 without using 
any new control technologies.
---------------------------------------------------------------------------

    \9\ 64 FR 31695 (June 14, 1999).
---------------------------------------------------------------------------

    Response: Regarding the characterization of high chromium 
refractories as a new technology, chromium refractories for use in the 
glass industry have been a developing technology. According to 
information provided by the wool fiberglass and refractories industries 
as part of this rulemaking, significant problems with their use in the 
furnace had to be overcome before wool fiberglass furnaces could be 
constructed using them. For example, when fused-cast refractories 
started to be developed using high chromium materials, some companies 
discovered ways to manufacture those products that maintained the 
integrity of the refractory over a long time and in extreme 
temperatures, making these products candidates for trials in the wool 
fiberglass industry. At least two

[[Page 45300]]

major corporations \10\ have developed high chrome refractory product 
lines since 1999, and they characterize these refractories on their Web 
sites as `new' products developed for the fiberglass industry. 
Therefore, our characterization of these products as `new' refers to 
the improvements in refractory and is not meant to imply that using 
chromium refractories, in and of itself, is new.
---------------------------------------------------------------------------

    \10\ The North American Refractories Company (NARCO) and the 
Saint-Gobain Corporation Web sites advertise product lines of 
refractories that are 50%-95% chromium for use in the glass fiber 
and wool fiberglass industries. From NARCO's Web site: ``Wool and C-
Glass makers rely on NARCO's extensive line of chrome-alumina 
materials, the SERV and JADE brands, available in standard pressed 
brick, large cast shapes, and Cast-in-Place linings. Supplying the 
complete furnace refractory package required for this application is 
a strength of NARCO''. (http://www.anhrefractories.com/glass-refractory). From Saint-Gobain's Web site: ``High temperature 
sintered chromium oxide based refractories have unequalled 
resistance against high temperature corrosion by molten 
SiO2-Al2O3- 
Fe2O3-CaO/MgO slags and by certain glass wool 
compositions, in an oxidizing environment. Saint-Gobain Ceramics has 
pioneered and patented a unique range of chromium oxide-alumina-
zirconia refractory compositions, marketed as . . .'' (from http://www.refractories.saint-gobain.com/Chromium-Oxide.aspx).
---------------------------------------------------------------------------

    Further, we noted in the November 2011 proposal that we identified 
``improvements'' in PM emissions controls, not that we identified 
``new'' controls. We acknowledged in both our November 2011 and April 
2013 supplemental proposals that sodium hydroxide scrubbers are not 
currently used in the wool fiberglass industry for removal of chromium, 
but that these controls are used in metallurgical processes and in the 
chromium electroplating industry for the removal of hexavalent 
chromium. We stated in those proposals that we were considering 
applying scrubber technology to this source category; however, as 
discussed in the 2014 supplemental proposal (79 FR 68020-69024), the 
technology basis for the chromium standard is more frequent furnace 
rebuilds, not scrubber technology.
    Moreover, as we explained in our 2013 supplemental proposal (78 FR 
22380), the type of furnace used to produce wool fiberglass at the 
highest emitting wool fiberglass manufacturing source was the type of 
furnace that is expected to dominate the industry in the future as a 
new and very efficient energy source. The oxyfuel furnace was not 
identified in our 1999 MACT standard as a separate technology. While we 
acknowledge that wool fiberglass furnaces are not `new' technologies, 
the oxyfuel furnace is both new to this industry and its use is 
increasing. As the industry has commented, air-gas furnaces are 
becoming increasingly difficult to permit, while an oxyfuel furnace has 
no such restrictions due to its low PM and NOX emissions 
profile.
    We are not changing our assessment of the industry controls as 
having improved since 1999, and we are lowering the PM limit in the 
final rule from 0.5 to 0.33 pounds PM per ton of glass pulled. This 
limit codifies the current good practices and PM controls within the 
industry while not imposing additional costs to industry.
    Regarding the commenter's allegation that chromium emissions were 
insignificant in 1999, and on that basis the EPA should not set 
chromium limits for this industry, we do not agree. The EPA has the 
responsibility to regulate air toxics under section 112 and to protect 
the health and environment surrounding these facilities as we are doing 
in this final rule. Moreover, due to source testing at the wool 
fiberglass industry, we have more information now than we had in 1999, 
and the industry's technology (that is, both the furnaces and 
refractories used) has changed.
    Regarding the statement that, since initial MACT implementation in 
1999, industry has reduced chromium emissions without using any new 
control technologies, the industry did not provide data showing that 
chromium emissions have been reduced.
    Comment: One commenter argued that chromium emissions from glass 
furnaces do not increase with age and that a relationship between 
furnace age and chromium emissions is not statistically significant. 
The commenter argued that erosion of the refractories is slow and there 
is no substantial increase in chromium emissions over time. The 
commenter noted that the EPA asserted that ``when the glass-melting 
furnace is constructed using refractories containing high percentages 
of chromium, the emission levels of chromium compounds continuously 
increase over the life of the furnace according to the increasingly 
exposed refractory surface area.'' The commenter noted that the EPA 
further explains: ``It is our understanding that because of the 
corrosive properties of the molten glass, fresh refractory is 
continuously exposed to the molten glass along the metal/glass contact 
line in the glass-melting furnace process. This increases the surface 
area of the refractory that is exposed to the molten glass. As a 
result, when the glass furnace is constructed using high chromium 
refractories, the emission levels of chromium compounds continuously 
increase over the life of the furnace.'' The commenter stated that this 
is not correct. The commenter explained that surface area of refractory 
exposed to molten glass does not substantially increase, nor do the 
chromium emissions as a result. The commenter asserted that the slight 
increase in surface area as between uneven and smooth surfaces of new 
brick exposed to molten glass cannot explain the major difference that 
the one source exhibited on chromium emissions. In fact, the commenter 
observed, the testing results provided by the industry included 
furnaces in all stages of their life. The commenter argued that given 
the nearly constant surface area as refractory erodes, and the 
homogeneous chrome content throughout the brick, there would be no 
substantial increased chromium emissions over time in the manner the 
EPA asserts. Furthermore, according to the commenter, the erosion 
process is very slow given the lifespan of these furnaces.
    The commenter stated that the EPA reports that ``[o]ne industry 
spokesperson estimated that 20,000 pounds per year of refractory are 
worn away from the inside walls of one wool fiberglass furnace and 
ducted to the control device before venting to the atmosphere.'' The 
commenter contended that the context of that statement is that furnace 
emissions are going through control devices that already meet the 
definition of BACT for particulate and if this were normal for the 
industry furnaces, they could not have the long lives that they 
typically exhibit.
    The commenter provided a detailed statistical analysis to 
demonstrate that a furnace rebuild is not a viable control technology 
by using EPA's data to show that a relationship between furnace age and 
chromium emissions is not statistically significant. Using the EPA's 
data, the commenter also pointed out specific examples of apparent 
contradictions with the EPA's conclusions, such as the data from one 
oxyfuel furnace showing lower chromium emissions at the end of its life 
than at the beginning of its life, and showing no change in emissions 
after a furnace rebuild. The commenter also points to data from another 
furnace demonstrating that emissions lessen with furnace age.
    The commenter contended that the proposed chromium limit is based 
on unproven technology, and that experimental and theoretical 
technologies do not constitute ``available'' or ``generally available'' 
technology. The commenter provided the results of various analyses to

[[Page 45301]]

demonstrate that there is no proven technology that can meet the 
proposed limit. The technologies represented in the commenter's 
analyses include high efficiency particulate air (HEPA) filter, Venturi 
scrubber, 3-stage filter with water cleaning, membrane baghouse, and 
caustic scrubber. The commenter described these technologies as 
``theoretical'' and ``unproven,'' because they have never been 
installed at the outlet of a DESP serving a wool fiberglass 
manufacturing furnace. The commenter contended that a membrane baghouse 
is used to control emissions from the industry, but has not been 
demonstrated to achieve the proposed chromium limit. The commenter 
provided feedback from vendors of these technologies to demonstrate 
that pilot tests would need to be conducted prior to vendors committing 
to guaranteeing a specific performance level. The commenter also 
investigated the performance capacity of the sodium hydroxide scrubber 
and found that this technology is not transferable to a wool fiberglass 
manufacturing process.
    Response: We disagree with the commenters on the basis of direct 
statements, measurements and information on refractory content, 
production rates and furnace life received from industry sources. We 
issued a CAA section 114 ICR to all five wool fiberglass manufacturing 
companies and visited four of the manufacturing facilities in December 
2012 to improve our understanding of the source of the chromium 
emissions from this industry. The results of these activities include 
source test data, information on chromium content of refractories used 
to construct different parts of all types of furnaces, and a deeper 
understanding of the properties of materials and technologies used to 
manufacture wool fiberglass. We were able to confirm our earlier 
statements presenting our understanding of this industry. Specifically, 
we confirmed that the furnace refractory are eroded and corroded during 
the life of the furnace both beneath the level of the glass, at the 
glass/metal contact line, and, in the case of gas-fired furnaces, above 
the level of the glass. We also learned that electric furnaces do not 
have the same temperature profile as gas-fired furnaces and, therefore, 
typically do not emit chromium at the level of the gas-fired furnaces.
    We also learned that oxyfuel furnaces are an important new 
technology both in terms of energy consumption and potential to emit 
SO2 and NOX, but have the greatest potential 
(followed by gas-fired furnaces) to emit chromium. We have established 
that furnace age affects chromium emissions, as documented in 
``Memorandum Chromium Emissions and Furnace Age, August 14, 2014'' and 
``Explanation of the Mechanisms of Chromium Emissions from Gas-Fired 
Furnaces, June 3, 2015'', which are available in the public docket for 
this rulemaking.\11\ We also disagree with the commenter's statistical 
analysis and argument that the EPA has not sufficiently established 
that there is a relationship between furnace age and chromium 
emissions. We have based our conclusions on industry comments, furnace 
emissions testing, technical literature, and other available data.
---------------------------------------------------------------------------

    \11\ EPA-HQ-OAR-2010-1042 at www.regulations.gov.
---------------------------------------------------------------------------

    In the letter dated March 12, 2012, the commenter stated that 
``Fiber glass furnaces necessarily use chrome-based refractory products 
(see Appendices A and B, spreadsheets showing typical chrome 
content),'' and that ``Virtually all of the above-glass refractory in 
gas-oxy furnaces, unlike other furnace classes, is chrome-based 
refractory.''
    In that letter, the commenter continued, explaining that ``Since 
the advent of chrome-based refractory, insulation manufacturers have 
been able to extend furnace life more than 50 percent. Without these 
refractories, wool fiberglass manufacturers would not likely be 
competitive in the global marketplace. Moreover, there currently is no 
available material that is as good as and has the structural integrity 
of chrome-based refractory to handle the higher temperature and more 
corrosive atmosphere inside gas-oxy furnaces.''
    Regarding the use of chromium refractories in oxyfuel furnaces, and 
the continual increase in chromium emissions that result, the commenter 
added that oxyfuel furnaces have greater chromium emissions than other 
furnaces because, based on industry experience, the combination of 
furnace design, glass composition, higher flame temperatures, higher 
water vapor concentration, and an oxidizing atmosphere with increased 
concentration of oxides (filterable and condensable PM) can cause more 
rapid deterioration of the refractory in a gas-oxy fiberglass 
insulation manufacturing furnace than in other types of glass furnaces.
    Regarding the comparison of operating temperatures of oxyfuel to 
other furnaces, the commenter added that, ``One advantage of gas-oxy 
firing is the large reduction in NOX, due to the reduction 
of nitrogen from the air in combustion, and the reduction in the volume 
of flue gases. One disadvantage of gas-oxy firing is that the peak 
flame temperatures are up to 40 percent higher than gas-air furnaces. 
The gas-oxy burner flame does not have to heat the added air 
components. In gas-oxy glass furnaces, peak flame temperatures approach 
5,000 degrees Fahrenheit, whereas air-gas flame temperatures peak at 
about 3,560 degrees Fahrenheit, and cold-top electric melters are even 
lower due to having no heat input above the glass line.''
    Regarding the relationship of furnace temperature and glass 
chemistry to chromium emissions, the commenter explained that ``with 
the reduction in the flue gas volume, the concentration of glass batch 
ingredient volatiles and water vapor in the atmosphere (and flue gas) 
is also much higher. The higher temperature of the gas-oxy burners can 
volatize the glass batch components more readily than in other 
furnaces. These glass volatiles that contain alkaline earth oxides 
reduce the temperature that chrome can be vaporized to as low as 1,832 
degrees Fahrenheit. While the chrome must still reach temperatures of 
2,700 to 2,900 degrees Fahrenheit to oxidize the chromium from the 
trivalent to hexavalent state, the potentially increased volatiles can 
contribute to higher chrome emissions. The 40 percent higher peak flame 
temperature of oxyfuel burners also raises the probability that 
available chrome (sic) will encounter the conditions that will convert 
it to the hexavalent state. Combined, these differences generate 
conditions that are more corrosive to chrome refractory and can create 
favorable conditions for conversion to hex chrome (CR206) inside a gas-
oxyfueled furnace. These severe conditions do not exist in the other 
fiber glass furnace classes.''
    Regarding the commenters' assertion that wool fiberglass furnaces 
could not be eroded by the molten fiberglass at the rate stated by 
industry, we note that the range of furnace life and rates of erosion 
did not originate from the EPA, but from information obtained from the 
industry itself. Further, we note that at the rate stated by industry 
and the control efficiency achieved by fabric filters, that refractory 
degrading at a rate of 20,000 pounds per year and fabric filters 
achieving 99-percent efficiency would emit 200 pounds PM annually from 
the contribution of the refractory alone. Using industry refractory 
content of 95-percent chromium, 190 of the 200 pounds of annual PM 
would be chromium compounds; 93 percent (177 pounds) of that chromium 
would be in the hexavalent state, which is within the range measured at 
oxyfuel and air-gas furnaces in this industry.

[[Page 45302]]

    Regarding the comment that there is no other technology available 
to meet the chromium limit, we note that all furnaces at existing area 
sources and all but two furnaces at existing major sources currently 
meet the final chromium limit. Regarding these two furnaces, the EPA 
has established that a furnace rebuild is an approach that existing 
facilities have used to reduce their chromium emissions for furnaces 
over 6 years old, as discussed in section III.D of the preamble to the 
2014 supplemental proposal. Further, the rule requires sources to meet 
the emission limits, but does not require the use of any specific 
control device or vendor. Sources may use whatever means they choose to 
meet the limits, such as more frequent furnace rebuilds, using non-
chromium or low chromium refractories in furnace rebuilds, enhanced 
baghouse operation, improved maintenance and alternative controls, and 
furnace design features, changes in raw material, or scrubbers.
    Comment: Two commenters asserted that the proposed chromium 
emissions limit would require technological controls that are not cost 
effective. According to one commenter, the installation of these 
controls would be economically damaging to the fiberglass insulation 
industry.
    The commenters cited the agency's estimated cost of $300 per pound 
of hexavalent chromium removed if a scrubber is used to comply and the 
agency's estimated cost of $12,000 per pound of chromium compounds 
removed if operations with high-chromium refractory are rebricked with 
low-chromium refractory. According to the commenters, the conclusion 
that the proposed new chromium limit is ``feasible and cost effective'' 
is unreasonable and arbitrary. One commenter observed that the EPA's 
cost-effectiveness values would be $600,000 per ton of chromium removed 
for scrubbers and $24 million per ton of chromium removed for 
rebricking, assuming either proposed compliance solution would actually 
be successful. As such, the commenters stated that the agency's cost-
effectiveness analysis does not support the conclusion that the new 
chromium limit is authorized and justified under CAA section 112(d)(6). 
One commenter claimed that the EPA's conclusion is arbitrary because 
the cost-effectiveness values are far in excess of the cost-
effectiveness values the EPA has found acceptable in prior CAA section 
112 cost-effectiveness analyses and the EPA has not explained why such 
high cost-effectiveness values are justified, especially considering 
risk.
    According to the commenters, fiberglass insulation producers 
provide economic benefits by adding manufacturing jobs to the U.S. 
economy, shipment of finished product to markets throughout the 
country, and export of product to foreign markets. According to one 
commenter, one reason jobs are being sent overseas is the existing 
regulatory requirements and concerns about the future regulatory 
climate growing even more stringent. If revisions are not made to the 
proposal as recommended by the commenter, many of the companies will 
cease operation and it is likely that foreign competitors will flood 
the market with substandard product.
    Response: We have reviewed the available chromium test data and 
information provided in response to our 2011 proposal, 2013 
supplemental proposal, and 2014 supplemental proposal (76 FR 72770, 
November 25, 2011; 78 FR 22370, April 15, 2013; and 79 FR 68011, 
November 13, 2014) and we have revised our technology review, the 
chromium limit and our economic impact analysis for the final rule.
    The EPA is finalizing a chromium limit of 0.00025 pounds per ton of 
glass pulled. Based on emissions data submitted in 2010 and 2012 by all 
wool fiberglass manufacturers on every furnace type, the EPA determined 
that this is a limit reflected by well-designed furnaces in this source 
category.
    As discussed in section VI.B of this preamble, all three of the 
furnaces that were tested in 2010, then rebuilt or repaired and 
retested in 2012, showed lower chromium emissions as a result of the 
furnace rebuild or repair. Of these three furnaces, two emitted 
chromium below the previously proposed limit of 0.00006 pounds of 
chromium per ton of glass pulled after the rebuild or repair. One, a 
new furnace, tested at about 0.0002 pounds of chromium per ton of 
glass, and had been rebuilt at a cost of about $10 million. 
Consequently, we revised our limit to reflect the level of chromium 
emissions that is achieved by a well-designed rebuilt furnace.
    Thus, the final emission limit is a level that has been 
demonstrated by recently rebuilt furnaces. We note that a key aspect of 
our changing the final chromium limit was to account for this new 
furnace, which measured chromium emissions at a level slightly higher 
than the limit we proposed.
    In our November 2014 supplemental proposal (79 FR 68012 at 68021), 
we presented a chart showing chromium emissions by furnace age. That 
chart indicates 0.00025 pounds per ton represents the level below which 
rebuilt furnaces operate and many gas-fired furnaces operate below this 
level beyond their tenth year. We are aware of new developments in the 
field of chromium refractories that reduce the spalling and degradation 
of the refractory face. We consider many of these to be design features 
which a wool fiberglass company would consider when planning to rebuild 
a furnace. These data demonstrate that well-designed furnaces (that is, 
furnaces designed and operated to minimize chromium emissions) can 
continue to meet the chromium limit as they age.
    This final rule does not limit the materials with which a gas-fired 
furnace may be constructed. Specifically, we recognize from industry 
commenters that gas-fired glass-melting furnaces used by the wool 
fiberglass industry will continue to use chromium refractories in their 
glass-melting furnaces. To help ensure that these sources are well-
designed to minimize chromium emissions, wool fiberglass gas-fired 
glass-melting furnaces will be required to conduct chromium emissions 
performance testing annually.
    Two facilities are projected to need to improve performance. For 
these two facilities, the total capital costs are $21.4 million and the 
total annualized compliance costs are estimated to be $944,000 for 
furnace rebuilds and compliance testing. For all other major source 
facilities subject to the chromium limit, the cost of compliance will 
include only the cost of emissions testing ($10,000 per furnace for a 
total of $80,000). Based on the EPA's economic impact analysis, which 
shows that the impacts to wool fiberglass manufacturers should be low, 
we believe that the compliance costs of the final rule are reasonable 
and will not be economically devastating to the wool fiberglass 
insulation industry.
    Regarding the comment requesting that the EPA compare the cost-
effectiveness of the proposed chromium limit (i.e., 0.00006 lb/ton of 
glass) to the cost effectiveness of standards finalized under other 
rulemakings, cost-effectiveness values for hexavalent chromium are 
generally not comparable to values for other less toxic pollutants. We 
note, however, that the values now estimated for hexavalent chromium 
are now well within the range that we have considered cost effective 
for other highly toxic pollutants (e.g., mercury and lead) in past 
actions. CAA section 112(d) neither specifies nor mandates a cost 
methodology. We note that in Husqvarna AB v. EPA, 254 F.3d 195, 200 
D.C. Cir. 2001), the D.C. Circuit found the EPA's chosen methodology 
``reasonable'' because the statute ``did

[[Page 45303]]

not mandate a specific method of cost analysis.''
    Comment: One commenter stated that the EPA's cost analysis for 
furnace rebuilds in support of the 2014 supplemental proposal (79 FR 
68011, November 13, 2014) underestimated the cost effectiveness by 
using the wrong costing method, incorrectly applying the costing method 
used, using the wrong discount rate, and considering costs over only 
the short term. The commenter provided the document ``National Emission 
Standards for Hazardous Air Pollutants (NESHAP) Risk and Technology 
Review (RTR) For the Mineral Wool and Wool Fiberglass Industries 
Economic Analysis Report,'' January 2015, as the source of this 
critique of the EPA's analysis.
    The commenter argued that the Net Present Value (NPV) methodology 
is not an appropriate method for calculating cost effectiveness of the 
proposed accelerated rebuild schedule if the EPA is evaluating the cost 
of a control as the single factor to consider, and also stated that 
they could not identify any EPA rules that have used this approach. The 
commenter suggested that a replacement cost analysis, as described in 
section 2.5.5.6 of the EPA Air Pollution Control Cost Manual,\12\ is 
more appropriate, and more commonly used by the EPA for this situation. 
The commenter provided cost-effectiveness results (dollars per pound of 
chromium emission reduction), as follows: Using a replacement cost 
methodology, the cost effectiveness was estimated by the commenter to 
be in the range of $366,161 to $527,334 at major source facilities and 
$67,808 to $97,654 at area sources; and using the NPV methodology, the 
cost effectiveness was estimated by the commenter to be in the range of 
$398,939 to $403,532 at major source facilities and $206,857 to 
$209,239 at area sources (each range represents the cost effectiveness 
calculated over 10 years versus 30 years).
---------------------------------------------------------------------------

    \12\ http://www.epa.gov/ttncatc1/dir1/c_allchs.pdf.
---------------------------------------------------------------------------

    The commenter further contended that the EPA erred in applying the 
NPV methodology in that the EPA excluded from its cost analysis the 
cost of losing the residual value (1 to 3 years) of a furnace's life, 
which contradicts the EPA's NPV methodology. The commenter explained 
that the EPA calculated what a $10 million investment losing 7 percent 
a year would lose in 7 years versus 10 years, and then concluded that 
the difference was the cost difference of the investments. The 
commenter contended, however, that both calculations are incorrect in 
how the process of NPV is used for comparison: With a furnace re-
bricking, the $10 million represents the investment that is consumed 
over the periods of comparison; and using the 10 years as a base case, 
the $10 million is consumed and has no residual value remaining at the 
end of the 10 year period. The commenter concluded that, therefore, the 
$10 million consumed with no residual value must be compared to a $10 
million investment that retains a residual value at the end of 7 years, 
but yet must be replaced (i.e., discounting the residual value at the 
end of the 7 years to present value (``PV'') and adding that to the 
annual costs).
    The commenter also objected to the EPA's use of a 7-percent 
discount rate because small variations in the discount rate can 
significantly bias the cost-benefit analysis. The commenter alleged 
that the EPA chooses radically different discount rates for different 
regulations, generally providing no explanation for this variation, 
which appears arbitrary and capricious because it often chooses 
relatively high discount rates (between 7 and 10 percent) for 
regulations imposing future costs and low rates (around 3 percent) for 
regulations creating future benefits.
    The commenter further argued that the EPA's cost analysis failed to 
look at the longer-term cost of 7-year rebuilds, beyond 10 years into 
the future. The commenter provided the results of an analysis that 
presented the impact over 30 years, which show higher costs for both 
area and major sources.
    Response: Regarding the comment that the EPA used the wrong costing 
method in the 2014 supplemental proposal, the EPA has reviewed the 
information provided by the commenter and, based on that information, 
which discussed the estimation of costs for changes in equipment that 
may occur as a route to comply with NESHAPs, we agree that the EPA's 
replacement costing approach described in section 2.5.5.6 of the EPA 
Air Pollution Control Cost Manual \13\ is more appropriate for 
estimating the cost of furnace rebuilds than the NPV approach used for 
the 2014 supplemental proposal.
---------------------------------------------------------------------------

    \13\ http://www.epa.gov/ttncatc1/dir1/c_allchs.pdf.
---------------------------------------------------------------------------

    We received new information from the industry that they believed 
the replacement costing (RC) approach was a better fit for the 
situation and approach than the NPV approach, which is what we had used 
at proposal. The NPV evaluated the loss to the company from having to 
rebuild a furnace earlier, (i.e., at 7 years into the furnace campaign 
instead of at 10 years.) The RC approach applies the equivalent uniform 
cost method as defined in the control cost manual. This is different 
because it calculates a uniform, or equal cost across the time of the 
investment, and the NPV is not calculated in the same way. While we 
note that use of the NPV is not necessarily incorrect in this case, we 
agree that in other similar rules whereby this type of approach was 
introduced (that is, replacing a process unit before the end of its 
useful life, or campaign in this case), the replacement costing 
approach was applied instead of the NPV. Therefore, we agree with the 
commenter and have changed our cost estimation method to be consistent.
    We also revised the capital cost estimate for rebuilding a furnace 
to include the cost ($700,000) of transferring production to another 
facility while the furnace is being rebuilt, based on information 
provided by the commenter. Based on the revised cost-estimating 
procedure and capital cost ($10.7 million), we estimated the total 
annualized cost for rebuilding a furnace to be $462,000.
    Regarding the comment that the EPA used the wrong discount rate, 
the EPA's use of a 7-percent interest rate is in accordance with OMB 
guidance under Circular A-4 and Circular A-94. This interest rate has 
been used in the cost estimates for all rulemakings issued by the 
Office of Air Quality Planning and Standards (OAQPS) since Circular A-
94 was issued in 1992 and affirmed by Circular A-4 in 2003. This 
includes the 2011 proposal for the mineral wool and wool fiberglass 
rules, and both supplemental proposals. In addition, the EPA Air 
Pollution Control Cost Manual \14\, a key cost guidance document 
prepared by the EPA and widely used in the Agency as a basis for cost 
estimation that has been available in its current edition since 2003, 
discusses the use of the 7-percent interest rate for rulemakings at 
length. The adherence by OAQPS to OMB guidance with regards to 
annualizing capital costs in its rulemaking has been consistent, and 
the information provided by the commenter on interest rates is not 
germane to the analysis for this rulemaking.
---------------------------------------------------------------------------

    \14\ http://www.epa.gov/ttncatc1/dir1/c_allchs.pdf.
---------------------------------------------------------------------------

    Comment: One commenter stated that the EPA's proposed chromium 
limit in the 2014 supplemental proposal (79 FR 68011, November 13, 
2014) was not cost effective because the EPA's cost analysis was 
missing the following costs associated with furnace rebuilds: New 
materials (refractory bricks); recycling and disposal of old material; 
installation

[[Page 45304]]

labor; maintenance; loss of production; and loss of labor force. The 
commenter retained a consultant to conduct a cost analysis of a furnace 
rebuild, and the analysis is provided by the commenter. The analysis 
concluded that the total investment of a furnace refractory rebuild is 
estimated to be about $28 million, assuming the EPA's furnace rebuild 
cost of $10 million. The $28 million includes approximately $7.9 
million for all materials, $2 million for installation labor, $60,000 
for brick recycling/disposal, $8 million for additional maintenance, $9 
million for loss of production, and $384,000 for loss of labor force. 
The commenter explained that the loss of production cost is based on 
200 tons per day throughput, $0.65 per pound of reproduction, and 35-
day shutdown period. These costs are listed in Table 2 of Appendix 2 of 
Docket ID No. EPA-HQ-OAR-1042-0348. The commenter explained that the 
additional maintenance cost includes maintenance of control equipment 
---------------------------------------------------------------------------
performed while the furnace is shut down during rebuild, as follows:

    Maintaining safe and proper operation at a wool fiberglass 
manufacturing facility requires that the facility maintain melted 
glass within the furnace at all times. In addition to the furnace 
operating continuously, all other equipment used in the 
manufacturing process, including air pollution control equipment 
operates continuously during normal operation. During a scheduled 
rebuild of the furnace refractory, a facility will use that downtime 
to perform routine maintenance on the entire manufacturing line. 
This maintenance requires longer downtimes to accomplish because it 
includes the support equipment for the furnaces as well as the major 
down line equipment such as forming sections, curing ovens, and line 
drives. This maintenance is done at this time to avoid the other 
operational expenses and product supply issues incurred when taking 
extended downtimes. Therefore, when a facility plans a refractory 
rebuild, it must consider the additional costs and logistics 
associated with the routine repair and general maintenance of the 
entire manufacturing line. NAIMA [North American Insulation 
Manufacturers Association] members estimate these additional costs 
to be in the range of $6,000,000 to $10,000,000, and include 
material (wear part replacements, pollution control device 
maintenance, electrical preventative maintenance, etc.) and labor to 
perform this maintenance. (Appendix 2 of Docket ID No. EPA-HQ-OAR-
1042-0348).

    Response: As noted in the information provided by the commenter 
(see Appendix 2 of Docket ID No. EPA-HQ-OAR-2010-1042-0348), the EPA's 
capital cost estimate of $10 million includes material costs, 
installation labor, and brick recycling/disposal costs. We also revised 
the capital cost estimate for rebuilding a furnace to include the cost 
($700,000) of transferring production to another facility while the 
furnace is being rebuilt, based on information provided by the 
commenter. We disagree that the cost of additional maintenance for 
control devices performed while the furnace is being rebuilt should be 
included in the total capital cost estimate because these costs are not 
directly related to rebuilding the furnace (i.e., the furnace could be 
rebuilt without performing maintenance on control equipment). We also 
disagree with the commenter that the cost of lost labor force suggested 
by the comment should be included because we believe that workers would 
be reassigned to other duties at the facility (including activities 
related to rebuilding the furnace) while the furnace is shut down.
    Comment: One commenter indicated that facilities will need to 
install control equipment to achieve the proposed chromium standard and 
that the EPA has grossly underestimated the cost of this equipment for 
major sources. One commenter provided cost-effectiveness estimates (in 
dollars per pound of chromium emission reduction) developed by Trinity 
Consultants for various technologies: HEPA filter would be $18,500 to 
$24,100; Venturi scrubber would be $29,700 to $41,700; 3-stage filter 
after DESP would be $49,100 to $63,900.
    Response: The EPA amended the proposed chromium limit for major 
sources to be 0.00025 pounds chromium per ton of glass pulled. Based on 
emission data submitted to the EPA in 2010 and 2012 by all major source 
wool fiberglass manufacturers for every furnace type, the EPA 
determined that all but two major source furnaces currently meet this 
chromium limit. For those two sources that will not initially meet the 
finalized chromium limit, the EPA determined that a furnace rebuild may 
be conducted to achieve the limit with no additional control 
technologies (e.g., scrubber).
    Note that the finalized chromium limit applies to gas-fired 
furnaces and does not apply to electric furnaces. Electric furnaces at 
major sources will not be subject to the final chromium emission 
limits, so wool fiberglass manufacturing facilities operating electric 
furnaces will not incur any additional costs for compliance with the 
finalized chromium limits.
    Comment: One commenter asserted that the EPA should subcategorize 
sources by furnace type because the chromium emissions test data 
indicate significant differences among wool fiberglass furnaces and 
furnace type. The commenter further asserted that non-oxyfuel furnaces 
should not have a chromium limit, and that oxyfuel furnaces should be 
further subcategorized to limit any applicable chromium emission limits 
to only those furnaces that warrant such limits. A second commenter 
asserted that the EPA should not subcategorize by furnace type.
    One commenter suggested the following list of subcategories: 
Oxyfuel, specialty, steel shell, air-gas, cold-top electric. The 
commenter characterized the EPA's authority to subcategorize as broad 
and discretionary, noting that the CAA authorizes the EPA to 
``distinguish among classes, types, and sizes of sources within a 
category'' in establishing MACT standards, and that the EPA retains 
discretion in important respects in setting floors for MACT standards 
within the statutory framework in order to promulgate MACT standards 
that best serve the public interest. The commenter continued, 
``Congress authorized EPA to subcategorize source categories based on 
classes, types and sizes of sources which will result in different 
[f]loors for different subcategories.'' The commenter observed that the 
EPA's criteria for subcategorization include ``air pollution control 
differences, process operation . . ., emissions characteristics, 
control device applicability and costs, safety, and opportunities for 
pollution prevention.'' The commenter also noted that the EPA had 
incorrectly stated ``[f]urnace construction and refractory composition 
were not factors that were presented by industry as having an effect on 
HAP emissions, and those factors were not used as a basis of 
representativeness for the resulting data set,'' which contradicted the 
May 5, 2010 testing proposal letter sent to the EPA that categorized 
furnaces by construction and identified furnaces as having an effect on 
emissions. The commenter stated that this identification by furnace 
type in the May 5, 2010 letter is precisely what the EPA should 
consider when subcategorizing.
    The commenter asserted that no subcategories except oxyfuel 
furnaces should have a chromium limit, noting that non-oxyfuel furnaces 
(steel shell, cold-top electric, air-gas, and specialty) have extremely 
low to non-detectable chromium emissions and referred to three 
supporting references: A summary of the chromium content of 
refractories and chromium emissions (attachment 8 of comment letter), 
the test reports sent to the EPA as a basis for the comment, and a 
technology review of glass furnaces (attachment 10 of the comment

[[Page 45305]]

letter).\15\ The commenter stated that the technology review 
(attachment 10) concluded that oxyfuel combustion has a much higher 
potential for generating hexavalent chromium emissions as compared to 
air-gas or other types of furnaces based on the following conclusions: 
(1) Chromium emissions result from volatilization from the surface of 
chromium alumina refractories used at or above the glass line in the 
melting furnaces, and (2) the most significant variable with respect to 
quantity of chromium volatilized and to the presence of hexavalent 
chromium is the flame temperature. The commenter cited the study's 
recommendations regarding subcategorization: ``Because of the very 
significant flame temperature differences between oxyfuel and air-gas 
furnaces (5,035 degrees Fahrenheit versus 3,562 degrees Fahrenheit, 
respectively), there is engineering rationale to differentiate or 
subcategorize the furnaces by combustion type from a standpoint of 
emissions . . . Other furnaces, such as cold-top melters and steel 
shell melters, should be in any lower emissions subcategory'' 
(attachment 10, p. 10).
---------------------------------------------------------------------------

    \15\ Denis A. Brosnan, Ph.D., PE, ``Technology Review, Chromium 
Emissions in Wool Fiberglass Melting Furnaces,'' December 10, 2011.
---------------------------------------------------------------------------

    The commenter further asserted that the EPA should go a step 
further and subcategorize oxyfuel furnaces to regulate only those 
furnaces that pose a concern. The commenter stated that the other 
oxyfuel furnaces other than the CertainTeed Kansas City, Kansas 
facility (a total of 12 furnaces) do not pose a concern because they 
show low chromium emissions and do not approach a level of emissions 
that would trigger MACT applicability. The commenter recommended the 
following possible approaches for subcategorizing oxyfuel furnaces: (1) 
Establish a subcategory of the oxyfuel furnaces based on variation in 
demonstrated chromium emissions; and (2) establish a subcategory of the 
oxyfuel furnaces based on sources that can demonstrate a less than 1-
in-1 million risk (using a risk-based source threshold limit of 25 
pounds per year).
    Another commenter urged the EPA not to subcategorize the glass-
melting furnaces used in the Wool Fiberglass Manufacturing source 
category. The commenter supported the EPA's recognition at proposal 
that it was inappropriate to subcategorize in the wool fiberglass 
source category, given that there are no relevant differences that 
distinguish among classes, types, and sizes of sources within the 
category. The commenter argued that use of different types of furnace 
bricks does not qualify as a basis for subcategorization because 
sources of the same class, type, and size use different bricks. 
According to the commenter, the EPA may not subcategorize the source 
category into high chromium-emitters and low chromium-emitters because 
that would violate the purpose of protecting public health and the 
purpose of ensuring that the best-performers drive CAA section 112(d) 
standards to become stronger. The commenter observed that best-
performers may have lower emissions, in part, because of the materials 
they use in their process or in their equipment. The commenter 
emphasized that the EPA may not lawfully subcategorize in a way that 
would place the best and worst performers into their own separate 
subcategories. The commenter asserted that the EPA should ensure that 
it sets standards for the entire source category that meet CAA section 
112 requirements, rather than subcategorizing in a way that may allow a 
source to evade stronger emission requirements.
    Response: In today's final rule, we are promulgating a PM limit 
under CAA section 112(d)(6) that is applicable to all glass melting 
furnaces in the Wool Fiberglass Manufacturing major source category. In 
our November 2011 proposal, we explained that in conducting our 
technology review, we found that most sources had reported PM emissions 
that were less than 10 percent of the current limit with several 
sources achieving PM emissions that were two to three orders of 
magnitude lower than the current MACT limit. We reasoned that new 
furnace designs and improvements in control devices operations, design, 
and bags since promulgation of the 1999 MACT were most likely 
responsible for reductions in PM emissions. As previously explained, 
the EPA may use surrogates to regulate HAP if there is reasonable basis 
to do so. In several rulemakings, we have used PM as a surrogate ``for 
HAP metals because PM control technology traps HAP metal particles and 
other particulates indiscriminately.'' National Lime Association v. 
EPA, 233 F.3d at 639. We continue to believe that PM controls would be 
effective for chromium emissions commensurate with the levels from both 
steel and electric furnaces used by wool fiberglass manufacturing 
facilities.
    In today's rule, we are also promulgating a chromium compounds 
limit under CAA section 112(d)(6) that will apply to gas-fired glass-
melting furnaces. As explained in the April 2013 supplemental proposal, 
electric furnaces emit metal HAP including chromium at generally lower 
emission levels than gas-fired furnaces. For example, because they 
operate at higher temperatures, gas-fired furnaces are constructed with 
chromium refractories at various parts of the furnace that are above 
the molten glass, including the crown. Temperatures above the melt in 
gas-fired furnaces range from 2500 to 4500 degrees Fahrenheit, and 
these temperatures are sufficient to convert chromium to its hexavalent 
state. When chromium is available, as it is in the refractories above 
the melt in gas-fired furnaces, it may be converted to the hexavalent 
state by the heat of the gas-fired furnace. Thus, gas-fired furnaces 
have the potential to emit elevated levels of chromium, even when 
meeting the total PM limit (78 FR 22379-82; 78 FR 22386). These higher 
chromium emissions do not occur with electric furnaces because they are 
constructed with either non-chromium refractories (cold-top electric) 
or steel in place of refractories (electric steel shell) above the 
glass/metal line. As also explained in our 2013 supplemental proposal, 
available test data from both electric and steel shell glass-melting 
furnaces consistently showed chromium emissions below the detection 
level of the emissions measurement method (78 FR 22379-80). Furnace 
construction and source test data also show that electric furnaces are 
not constructed using high-chromium refractories above the glass-metal 
line, do not reach the temperatures necessary to transform chromium to 
the hexavalent state, and do not emit significant amounts of chromium 
compounds, as do the gas-fired furnaces. In fact, all test data for 
electric furnaces show that chromium emissions were below the detection 
limit or were at least one order of magnitude below the proposed limit. 
Based on test data and statements from industry, we confirmed that gas-
fired glass-melting furnaces are constructed using similar high-
chromium refractories as one high emitting glass-melting furnace, that 
chromium emissions increase with furnace age as the refractories age, 
and that the type of furnace at the high emitter is an emerging new 
technology that is preferred across the industry where a source of 
industrial oxygen is economically available.
    Additionally, as also explained in today's final rule, we are 
finalizing a chromium compounds limit, under the ample margin of safety 
step of CAA section 112(f)(2), that will also apply to gas-fired glass-
melting furnaces. As explained above, gas-fired (oxyfuel and

[[Page 45306]]

air-gas) furnaces have the greatest potential to emit chromium 
compounds because they have the internal temperature, the availability 
of oxygen, reactivity, and corrosivity of the furnace environment that 
are typical of wool fiberglass furnaces. In the 2013 supplemental 
proposal, we explained that the elevated chromium emissions from gas-
fired furnaces are of concern due to the toxic nature of the type of 
chromium emitted--hexavalent chromium--and the effects associated with 
its inhalation. For example, hexavalent chromium is classified as a 
Class A known human carcinogen (78 FR 22374). In the November 2011 
proposal, we also explained that an auxiliary risk characterization 
analysis, to assess the potential maximum individual lifetime cancer 
risks in the event that all wool fiberglass manufacturing facilities 
emitted at the level of the highest hexavalent chromium emitter, 
indicated that if other facilities were to emit at that reasonable 
highest measured level, emissions of hexavalent chromium could 
potentially pose unacceptable risks to public health due to inhalation 
exposures resulting from stack emissions of hexavalent chromium (76 FR 
72801-80). We provided a detailed explanation on our decision to set 
both PM and total chromium standards in the memorandum titled 
``Technical Basis for Separate Chromium Emission Limits for Wool 
Fiberglass Glass-Melting Furnaces'', which is in the docket for this 
rulemaking.
    Comment: Two commenters predicted that the environmentally 
beneficial use of recycled mixed and green glass (cullet), and the 
businesses that provide it, will be adversely impacted by the chromium 
limit. The commenters pointed out that in 2008-2011, member companies 
used more than 5.4 billion pounds of recycled glass, and that they are 
the largest user of mixed glass and the only large user of green glass. 
These commenters surmise that some chromium may be emitted from cullet 
when it is remelted in the furnace, and that companies may reduce their 
use of green cullet to meet the chromium emission limits, an outcome 
that the commenters see as undesirable. The commenters added that the 
highest chromium emissions were measured from the furnace that also fed 
the most green glass cullet as a fraction of total raw materials into 
the furnace during the test period. One commenter noted that ``not all 
chrome was retained in the glass (cullet),'' and that green glass 
cullet ``can be a primary contributor of chrome emissions.''
    Response: As discussed in an attachment to comments submitted on 
the EPA's 2011 proposal, the wool fiberglass ``recipe'' uses alkali or 
alkaline earth oxides, or boron oxide (borax) for its properties to 
terminate chains and sheets of silicon and oxygen tetrahedral in the 
glass melt.\16\ The result of this process is the formation of 
macromolecules. These macromolecules are kinetically unable to 
crystallize at low temperature and, as a result, essentially polymerize 
the glass.
---------------------------------------------------------------------------

    \16\ Technology Review. Chromium Emissions from Wool Fiberglass 
Melting Furnaces. Brosnan, Denis A. Ph.D., PE. Clemson University, 
Clemson, SC February 1, 2012.
---------------------------------------------------------------------------

    The comment attachment further explains that chromium enters the 
glass in wool fiberglass furnaces below the glass line, and goes into 
solution without having the potential for volatilization at glass-
melting temperatures.\17\ Chromium enters the silicate network 
structure of the glass as a ``modifier'' of the network, and cannot 
form glass on its own due to thermodynamic constraints. Chromium is 
held ``rigidly'' in the silicate structure in interstices in the atomic 
network, and is present in coordinated complexes with oxygen.\18\
---------------------------------------------------------------------------

    \17\ Chromium volatilization is only reported in the non-
equilibrium melting of glasses at plasma processing temperatures, 
i.e., with flame temperatures typically reported as above 7,000 
degrees Celsius (>12,000 degrees Fahrenheit). Brosnan, 2012.
    \18\ C. Nelson, Transition Metal Ions in Glasses: Nework 
Modifiers or Quasi-Molecular Complexes, Mat. Res. Bull. 18 (1983) 
959-966.
---------------------------------------------------------------------------

    Further, based upon comments from industry, technical literature, 
refractory product specifications, and other data, we conclude that the 
chromium is not released from the cullet when it is melted, but from 
the chromium refractories due to several influencing factors: The glass 
chemistry, furnace temperatures, refractory wear rate and glass pull 
rate. For more information regarding this topic, see memo titled 
``Mechanisms of Chromium Emissions From Wool Fiberglass Glass-Melting 
Furnaces, June 2015'' in the docket to this rule.
    However, we agree that the chemistry of the internal furnace 
environment may be influenced when green glass cullet comprises most or 
nearly all of the raw material mixture used in the furnace. This may be 
due to reaction of submetallic oxides (boron) with the chromium oxide 
of the refractory. As described in the comment attachment, ``the basics 
of glass melting are well-known, with fluxes acting on silicon dioxide 
or SiO2 to achieve a melted state that forms an amorphous 
``network'' of atoms of oxygen and silicon with ``fluxing'' metals 
resulting in rigid solids at room temperature.'' \19\ The attachment 
concludes that, ``Below the glass line in mineral wool \20\ (sic) 
furnaces, chromium from refractory corrosion enters the network 
structure of the molten glass where it is held to the extent that it is 
not volatile at the flame temperatures of batch temperature within 
these furnaces. Therefore, volatilization from chromium refractories 
within mineral fiberglass furnaces originates at or above the glass 
line in the furnaces from the exposed refractory surfaces.''
---------------------------------------------------------------------------

    \19\ W. David Kingery, H. Bowen, and D. Uhlmann, Introduction to 
Ceramics (2nd Edition), Wiley (1976).
    \20\ This report was attached to a comment to the November 25, 
2011, Wool Fiberglass Manufacturing proposed RTR rule, and offers 
the author's view on the technology review for wool fiberglass 
furnaces. We conclude his use of the term `mineral wool' in this 
context may have been either an error (the author advises on both 
industries) or an inclusion of wool fiberglass as a sub-
classification under the overall classification (see NAICS codes) of 
mineral wool.
---------------------------------------------------------------------------

    To summarize, according to the commenter, the minerals used to 
color these glasses is not re-emitted from the cullet when it is melted 
at the temperatures of wool fiberglass furnaces. According to the 
commenter, studies show that in order to volatilize chromium from 
glass, temperatures above 7,000 degrees Celsius (12,000 degrees 
Fahrenheit) (such as occurs at plasma processing temperatures) are 
required (Brosnan, 2012).
    Therefore, we disagree with the commenter's assertion of the 
mechanism of chromium emissions from the furnace, i.e., that chromium 
is volatilized from green glass cullet when it is remelted in the wool 
fiberglass furnace.
    To the contrary, we maintain that chromium emissions are due to 
chromium refractory products in wool fiberglass furnaces. According to 
the literature and references, many of which were provided by the 
commenter, chromium emissions increase from the wool fiberglass furnace 
as a result of degradation of chromium refractories, which is 
influenced by the thermochemical interactions within the furnace 
environment. The rate of degradation of the chromium refractory in the 
wool fiberglass furnace is influenced by the thermochemical 
interactions which are influenced by the raw material mixture processed 
in the furnace and the use of cullet (of any color).
    We note that the test results upon which the final limits are based 
include tests conducted while the furnace was processing cullet in the 
raw material

[[Page 45307]]

mixture. While the technology basis for the final standard is more 
frequent furnace rebuilds, wool fiberglass furnace operators may choose 
among a variety of options, as explained in section III.D of the 2014 
preamble. Commenters previously identified several options to meet the 
final standard, including raw material substitution, i.e., reducing the 
amount of cullet processed in the furnace. In addition to raw material 
substitution, industry commenters included the furnace rebuild and 
installation of a control technology at the outlet of the DESP as 
potential chromium reduction measures.
    Regarding the prediction of the commenters that negative 
environmental impacts will result from the chromium limits because 
green glass will be landfilled instead of remelted by the wool 
fiberglass industry, we disagree for the following reasons. First, 
glass recycling in the past was accomplished through the color 
segregation of glass materials: Brown, or amber glass for amber 
containers; clear, or ``flint'' for flint containers; and green glass 
for green containers. Recycling centers no longer segregate their glass 
by color, but instead separate recyclable materials according to type: 
Paper, aluminum, steel, and glass, where glass of all colors is 
combined together in a single stream. Therefore, we disagree with the 
commenter that vast amounts of green glass would be landfilled because 
glass recycling no longer segregates waste glass by color.
    Second, we acknowledge that while mixed glass from single stream 
recycling may be difficult to sell as a raw material, recyclers now 
decolorize used glass for resale into all glass markets (container 
glass in particular). One recycler (GMG) in particular shared a 
description of their process: ``GMG's basic technology provides for the 
de-colorization and subsequent recolorization of mixed color cullet in 
the production of glass containers. In so doing, it allows the glass 
manufacturer to use multiple colored cullet (amber, green, flint) to 
produce a single color glass, matching rigorous color and 
transmissivity standards required for many glass products. It 
accomplishes this in a manner that allows the glass manufacturer to 
replace virgin raw materials with a former waste product (mixed 
cullet). GMG's Batch Formulation System (BFS) is a user-friendly 
software program based upon a GMG proprietary series of algorithms 
representing the full spectrum of furnace batch materials and their 
chemistry. The BFS technology, combined with the optical scanning 
equipment, enables the manufacturer to further increase savings through 
the use of start-of-the-art optical scanner/feeder with advanced 
software that instantaneously reports color distribution weights and 
cullet chemistry in each batch sent to the furnace. Using these real 
time reports on the incoming cullet stream, the furnace operator can 
make formula modifications in chemicals and virgin materials to ensure 
uniform colored glass production.''
    Third, the wool fiberglass industry is one of several glass 
industries, including mineral wool, container glass, pressed and blown 
glass, and flat glass, that purchase glass cullet as an inexpensive and 
energy efficient raw material. Therefore, we disagree that glass cullet 
would necessarily be landfilled instead of used in one of any number of 
glass industries.
    Fourth, because chromium does not readily leach out of vitrified 
materials such as glasses, and would not further pollute the 
environment if disposed in a landfill, we believe that even if green 
glass cullet were landfilled in some areas, that would not result in a 
worse environmental impact than for chromium (particularly in its 
hexavalent form, as is most of the chromium from wool fiberglass) to be 
released into the air upon remelting.
    Finally, according to the commenter, the use of cullet is required 
by Executive Order, and wool fiberglass companies avail themselves of 
cullet as a low-cost, energy efficient raw material which is also used 
to increase wool fiberglass production rates due to the lower melting 
temperature and eutectic point (as compared to all raw minerals). Wool 
fiberglass manufacturers have stated that they would need to greatly 
reduce or eliminate their use of cullet in the oxyfuel furnaces in 
order to meet the proposed chromium limit (0.00006 lb/ton of glass 
pulled), but that it is a moot point at the final chromium limit 
(0.00025 lb/ton of glass pulled). During meetings held in December 2014 
and March 2015, industry stated that reducing or eliminating the use of 
cullet in the oxyfuel furnaces as a way to meet the chromium emission 
limit was no longer a concern to them. Furthermore, use of cullet in 
electric furnaces (which are not impacted by the chromium limit) does 
not seem to increase emissions of chromium as it does in gas-fired 
furnaces. Therefore, this is not an issue for electric furnaces, which 
will continue to use cullet. Therefore, we disagree with the commenter 
that cullet providers will be adversely affected by these final rules.
    For the reasons stated above, we disagree with the commenter that 
there are environmental impacts associated with glass recycling that 
should be included in the impacts analysis. However, changing the 
content and mixture of raw materials used in a process can be a viable 
option for regulated sources to meet emissions limits.
4. What is the rationale for our final approach for the technology 
review?
    In our technology review under CAA section 112(d)(6), for PM we 
found that while the use of ESPs is not new to this industry, the use 
of the DESPs in combination with gas-fired furnaces is more prevalent. 
We found that, in general, baghouses are no longer used for gas-fired 
glass-melting furnaces. We also found that all glass-melting furnaces 
were achieving emissions reductions that were well below the existing 
MACT standards regardless of the control technology in use.
    Therefore, we determined that emissions controls on furnaces are 
capable of reducing PM to levels below those in the MACT standard, and, 
as previously proposed in our April 2013 supplemental proposal, we are 
finalizing under CAA section 112(d)(6) the PM limit for new and 
existing glass-melting furnaces.
    Section 112(d)(6) of the CAA provides that the agency must review 
and revise ``as necessary'' existing MACT standards taking into 
consideration developments in practices, processes and control 
technologies by affected sources. The ``as necessary'' language must be 
read in the context of the provision, which focuses on the review of 
developments that have occurred in the industry since the time of the 
original promulgation of the MACT standard. Thus, our technology review 
was for all glass-melting furnaces located at both area and major 
sources, since all area sources were originally major sources. As 
explained in our April 2013 supplemental proposal, the number of area 
sources is continually increasing as a result of the definition of 
``wool fiberglass facility'' in 40 CFR 63, subpart NNN. For example in 
2002, two out of 33 facilities were area sources, but by December 2012, 
20 facilities were area sources (78 FR 22377). As also previously 
explained, there are no differences between gas-fired glass-melting 
furnaces used at major and area sources (78 FR 22377). Therefore, we 
believe it was appropriate to consider all furnaces in our technology 
review under CAA section 112(d)(6).
    Based on public comments and test data, we found that the DESP 
achieves an average of 97.5-percent efficiency in reducing PM, a 
fraction of which is

[[Page 45308]]

chromium compounds. Test data indicate that the majority of this 
chromium is in the hexavalent state, which is the most toxic form of 
this pollutant. We concluded that, as earlier discussed, the mechanism 
of formation, the increasing rate of emission release (due to 
refractory degradation), and the pollutant toxicity warrant additional 
investigation. Our technology review indicates that options effective 
in reducing the chromium compound emissions from the furnaces are 
available to wool fiberglass companies. We, therefore, conclude that it 
is appropriate for us to set standards for the fraction of chromium in 
the total PM that is still emitted from the DESP.
    Based on comments we received on the November 2014 supplemental 
proposal, we again reviewed the cost and control options and found 
using new cost information that the limit as proposed was not as cost 
effective as we initially believed. We reviewed the data to determine 
whether a higher limit than previously proposed would be more cost 
effective while still significantly reducing chromium emissions from 
wool fiberglass gas-fired glass-melting furnaces. We found that most 
wool fiberglass gas-fired glass-melting furnaces and all recently 
rebuilt gas-fired furnaces currently emit chromium compounds at rates 
below 0.00025 pounds chromium per ton of glass pulled. Two furnaces 
located at major sources, which together emit 583 pounds of chromium 
compounds per year after DESP control, would still have to reduce 
chromium emissions to meet the limit.
    We compared the chromium emission reductions that would have 
resulted under the previously proposed emission limit of 0.00006 pounds 
chromium per ton of glass pulled to the reductions that result from the 
final limit of 0.00025 pounds chromium per ton of glass pulled. We 
found that the proposed limit would have reduced chromium from major 
sources by 567 pounds per year, and that the final limit reduces 
chromium by 524 pounds per year. These are comparable and substantial 
reductions in chromium due to two high-emitting furnaces at major 
sources. Moreover, the final limit sets a backstop so that another 
high-chromium-emitting, gas-fired glass-melting furnace cannot be 
operated again at a major source in this industry.
    We revised our technology review to reflect our conclusions on the 
most cost-effective ways to meet the final chromium limit. We find that 
two approaches are likely to be used by industry to reduce chromium 
emissions from gas-fired furnaces. One approach is to rebuild the 
furnace early (instead of a furnace life of 10 or more years, rebuild 
the furnace after 7 years of service) at an annualized cost of $462,000 
per year, and the other approach is to replace one raw material 
(cullet) with another material (raw minerals), which the industry 
stated would result in lower chromium emissions, at an average cost of 
about $620,000 per year. Industry test data show that major sources 
will reduce chromium emission by 524 pounds per year to meet the 
0.00025 pounds chromium per ton of glass pulled limit. The cost 
effectiveness of both approaches is reasonable, and the option to 
rebuild the furnace has a cost effectiveness of approximately $880 per 
pound of chromium, which appears for most companies to be the most 
cost-effective option. This cost is extremely affordably compared to 
costs for chromium control in other rules. For example, in the Chromium 
Electroplating RTR (77 FR 58226, September 19, 2012), we accepted a 
cost effectiveness of $11,000 per pound of hexavalent chromium reduced. 
We also note that section 112(d) neither specifies nor mandates a cost 
methodology. We note that in Husqvarna AB v. EPA, 254 F.3d 195, 200 
D.C. Cir. 2001), the DC Circuit Court found the EPA's chosen 
methodology ``reasonable'' because the statute ``did not mandate a 
specific method of cost analysis.''
    Sources may choose a combination of these approaches to meet the 
final chromium limit: Raw material substitution may be used as the 
furnace begins to show refractory wear (and associated increase in 
chromium emissions), and then, toward the end of the useful life of the 
furnace, sources may choose to rebuild their process equipment. We 
discuss the technology review in more detail in the November 2011 (76 
FR 72803-72804) and the April 2013 (78 FR 22379-382) proposals; in the 
``Technology Review Memorandum for the Wool Fiberglass Manufacturing 
NESHAP''; and in the paper titled, ``Mechanisms of Chromium Emissions 
From Wool Fiberglass Glass-Melting Furnaces,'' June 2015; which are 
available in the docket to this rule.

C. MACT Standards for Pollutants Previously Regulated Under a Surrogate 
and Previously Unregulated Pollutants for the Wool Fiberglass 
Manufacturing Source Category (Major Sources)

1. What did we propose pursuant to CAA sections 112(d)(2) and (3) for 
the Wool Fiberglass Manufacturing source category (major sources)?
    In the November 2011 proposal, we proposed to establish emissions 
limits for formaldehyde, methanol, and phenol from FA and RS 
manufacturing lines that were previously regulated under a surrogate, 
and previously unregulated HCl and HF from glass-melting furnaces. In 
the April 2013 supplemental proposal, we retained the proposed emission 
limits for formaldehyde, methanol, and phenol for FA and RS 
manufacturing lines; however, we proposed work practice standards under 
CAA section 112(h) for control of HF and HCl emissions from furnaces, 
instead of the numeric emission limits in the November 2011 proposal 
(see section V.D of this preamble). In the November 2014 supplemental 
proposal, we proposed revised emissions limits for formaldehyde, 
methanol, and phenol from RS and FA lines for new sources as a result 
of our updated approach to evaluate limited datasets. The emission 
limits for existing RS and FA lines in the November 2014 supplemental 
proposal remained the same as in the April 2013 supplemental proposal 
because the size of these datasets was sufficiently large that the 
limits were not changed by the updated approach.
    For the sake of simplicity, we discuss these pollutants together in 
the following sections.
2. How did the formaldehyde, methanol, and phenol emission limits 
change for the Wool Fiberglass Manufacturing source category?
    We have not changed any aspect of the emission limits for 
formaldehyde, methanol, and phenol for existing and new FA 
manufacturing lines since the November 2014 supplemental proposal. 
However, as explained in section V.H of this preamble, we are deferring 
evaluation of emissions limits for RS lines pending collection of new 
process and emissions data from the industry.
3. What key comments did we receive on the formaldehyde, methanol, and 
phenol emission limits, and what are our responses?
    We received comments in support of and against our proposed 
formaldehyde, methanol, and phenol emission limits for FA lines. The 
following is a summary of the key comments received

[[Page 45309]]

regarding the revised formaldehyde, methanol, and phenol emission 
limits for FA lines in the Wool Fiberglass Manufacturing source 
category and our responses to these comments. Additional comments on 
the standards and our responses can be found in the comment summary and 
response document available in the docket for this action (EPA-HQ-OAR-
2010-1042).
    Comment: One commenter expressed concern that the EPA is changing 
the applicability of the MACT standard for products made on FA 
manufacturing lines, as the 2013 supplemental proposal (78 FR 22370, 
April 15, 2013) indicated that the limits apply to all products 
manufactured on an FA line, not only to pipe and heavy density 
products. The commenter interpreted this to expand applicability of 
MACT to lines not previously regulated, which is beyond the EPA's 
authority under section 112 of the CAA. In the commenter's opinion, the 
limits for FA lines should continue to apply only to pipe and heavy 
density products, and not to any other product made on an FA line.
    Response: The EPA changed the applicability of the MACT standard 
for products made on FA manufacturing lines for two reasons. First, the 
EPA determined under this rulemaking that the EPA established the 1999 
MACT floor as no control (i.e., no limit was established) for 
formaldehyde emissions from FA lines producing light density products 
(new and existing), automotive products (new and existing), and heavy 
density products (existing). As stated in the March 31, 1997, proposal 
for the Wool Fiberglass Manufacturing NESHAP (61 FR 15230), we divided 
FA lines into four subcategories: light density, automotive, heavy 
density, and pipe products. In that proposal (61 FR 15239), we noted 
that we did not establish emission limits for existing FA manufacturing 
lines producing light-density, automotive or heavy-density products or 
emission limits for new FA manufacturing lines producing light-density 
or automotive products because the MACT floor was no control and 
because the cost effectiveness of additional controls beyond the floor 
was not reasonable. The DC Circuit Court explicitly rejected this 
approach--establishing the MACT floor as no control--in both National 
Lime Association v. EPA, 233 F. 3d at 633-34 and in Portland Cement 
Association v. EPA, 665 F.3d 177, 189 (D.C. Cir. 2011). Therefore, the 
EPA has both the authority and the obligation to change applicability 
for FA lines to ensure that all sources of HAP are regulated.
    Furthermore, we believe that the data for these facilities clearly 
support the establishment of MACT floors that assure emissions 
controls. The standards are based on data we received on tested FA 
lines. The commenter did not provide additional test data or 
information on ``any other product made on an FA line'' that would lead 
us to change to the emission limits previously proposed for FA lines.
    Second, in our April 2013 supplemental proposal, in response to 
comments on our November 2011 proposal, and consistent with our intent 
in the 2011 proposal, we stated that we were eliminating the 
subcategories for FA bonded lines because we believe that the technical 
or design differences that distinguished these subcategories in 1999 no 
longer exist (78 FR 22387). We stated in the 2013 preamble that, as 
part of rule development, industry provided test data that they claimed 
were representative of products manufactured on FA lines (refer to 
industry's May 10, 2010, letter to the EPA, available in the docket). 
The 2011 and 2012 ICR response data indicate that only one company uses 
FA processes to manufacture wool fiberglass products. This is the 
company that provided the test data on which the limits for FA lines 
are based. In comments, companies asked that the limits for FA lines 
apply only to pipe and heavy density, and not to ``any other product 
made on an FA line.'' However, no other companies provided additional 
data that could serve as a basis for a change to the proposed limits 
for FA lines for any other products being produced on FA lines. The 
data provided by industry, therefore, indicate that this one company is 
the only company engaged in manufacturing wool fiberglass products on 
an FA line. Because test data exist for multiple products from this one 
company reporting these activities, we disagree with the commenter that 
the limits for FA lines should continue to apply only to pipe and heavy 
density products, and we are finalizing limits developed for FA lines 
that are representative of all product types made on FA lines. 
Consistent with our 2013 supplemental proposal, we are establishing 
standards at the MACT floor level of control for phenol, formaldehyde 
and methanol emissions from FA bonded lines.
    In 2007, the D.C. Circuit Court found that the EPA had erred in 
establishing emissions standards for sources of HAP in the NESHAP for 
Brick and Structural Clay Products Manufacturing and Clay Ceramics 
Manufacturing, 67 FR 26690 (May 16, 2003), and consequently vacated the 
rules. (Sierra Club v. EPA, 479 F. 3d 875 (D.C. Cir. March 13, 2007)). 
Among other things, the Court found the EPA erred by failing to 
regulate processes that emitted HAP. As required by CAA section 112, we 
must establish emission limits for all processes that emit HAP based on 
the information available to us. The data available to the EPA indicate 
that FA lines producing products other than pipe and heavy density 
products do emit HAP. Therefore, the EPA is obligated to set limits for 
formaldehyde, phenol, and methanol for any such FA lines.
    Comment: One commenter expressed concerns regarding the EPA's 
proposed limits for formaldehyde, phenol, and methanol. Regarding the 
2011 proposal, the commenter asked the EPA to consider the example of 
one company whose compliance test data indicate that after switching to 
a non-phenol/formaldehyde binder, the level of formaldehyde and 
methanol for its RS line would exceed the 2011 proposed standard of 
0.02 pounds per ton for formaldehyde for RS lines and the proposed 
standard for methanol of 0.00067 pounds per ton for new and 
reconstructed RS lines. According to the commenter, the data also 
suggested that an RS line at an existing source using non-phenol/
formaldehyde binders would not meet the 2011 proposed formaldehyde 
standard of 0.17 pounds per ton for RS lines. The commenter also 
contended that the phenol limit of 0.0011 pounds per ton in the 2011 
proposal for RS lines is so low that it cannot be measured with normal 
test times or with the proposed method if the process is performing 
close to the limit. The commenter concluded that the sources that 
switch to non-phenol/formaldehyde binders would not be able to comply 
with the proposed standards without installing controls such as a 
thermal oxidizer, which suggested the proposed standards are 
inappropriate. The commenter objected to the EPA's calculating the MACT 
floor using data for RS lines using non-phenol/formaldehyde binders. 
The commenter asserted that non-phenol/formaldehyde binder lines are 
not representative of emissions in the affected units within the 
industry, and non-phenol/formaldehyde binder lines should not be used 
to set the MACT floor for formaldehyde, phenol, and methanol. The 
commenter requested that the EPA confirm that all test data used to set 
new and revised limits are based only on data from sources running a 
bonded product, and to confirm that none of the test data used to set 
the new and revised limits are based on data from sources

[[Page 45310]]

running a non-phenol/formaldehyde binder or unbonded product.
    Regarding the 2013 supplemental proposal, the commenter maintained 
that formaldehyde and methanol standards are not feasible for certain 
RS lines without installing both non-phenol/formaldehyde binder and 
additional controls such as thermal oxidizers, because of the 
formaldehyde created through combustion of natural gas. The commenter 
specifically mentioned the formaldehyde standard of 0.19 pounds per ton 
for RS lines as being borderline achievable for non-phenol/formaldehyde 
binders in RS lines for existing sources.
    Regarding the 2014 supplemental proposal, the commenter indicated 
that the level of formaldehyde and methanol emitted by RS lines would 
exceed the 2014 proposed standard of 0.087 pounds per ton for 
formaldehyde and the 2014 proposed standard for methanol of 0.61 pounds 
per ton for new and reconstructed sources because of the formaldehyde 
created through combustion of natural gas. The commenter added that the 
data also suggest that the formaldehyde standard of 0.19 pounds per ton 
is borderline passing for non-phenol/formaldehyde binder on some 
existing sources. The commenter explained that formaldehyde is a by-
product of natural gas combustion from burners used in the process. The 
commenter indicated that the proposed phenol limit of 0.26 pounds per 
ton is greatly improved since the 2011 proposed limit, but that it is 
still not consistently achievable. The commenter concluded that the 
proposed standards may not be able to be achieved even after switching 
to non-phenol/formaldehyde binders without installing controls such as 
a thermal oxidizer, which themselves will emit additional formaldehyde 
as a result of the combustion of natural gas to operate the control 
device.
    Response: We agree with the commenter that the data used to 
calculate MACT for major sources must not include data for RS lines 
that run a non-phenol/formaldehyde binder or unbonded product. As 
discussed in the 2013 supplemental proposal (78 FR 22387), in response 
to the comment on the 2011 proposed emission limits for RS lines, we 
recalculated the emission limits after removing the emission test data 
for RS lines using non-phenol/formaldehyde binders, and we re-proposed 
emission limits for RS lines. However, based on this comment, we 
determined that our proposed formaldehyde, phenol, and methanol limits 
for RS lines may not accurately represent the average performance of 
the best performing sources. In 2015, after considering further 
information provided by industry representatives, we determined that 
the limits proposed in 2014 for RS lines likely included RS lines using 
non-phenol/formaldehyde binders and that the EPA could not determine 
(based on the 2011 ICR data) which data represented manufacturing lines 
that were using phenol/formaldehyde binders, and which data represented 
manufacturing lines that were not using the phenol/formaldehyde binder. 
As a result, we are not establishing in this final action RTR standards 
for formaldehyde, phenol, and methanol for RS manufacturing lines at 
wool fiberglass manufacturing facilities. We have issued an ICR under 
section 114 of the CAA to collect updated emissions and process 
information from the industry, and we will analyze the ICR data and 
evaluate limits for RS lines at wool fiberglass manufacturing 
facilities at a future date.
    Comment: One commenter argued that the EPA should not recalculate 
the MACT floor for formaldehyde emissions and that the current MACT 
floor for formaldehyde emissions is still valid. The commenter 
contended that the EPA should not set a MACT floor for formaldehyde for 
the second time, explaining that (1) the EPA has not provided an 
explanation or asserted any rational basis for choosing to calculate a 
new MACT floor and standard for formaldehyde, as opposed to using its 
discretion under CAA section 112(d)(6) to make an appropriate 
adjustment without recalculating the floor and standard; and (2) there 
is no basis under the technology review to recalculate a MACT floor.
    The commenter stated that nothing in CAA section 112(d) suggests 
that the EPA is required to establish a floor under CAA section 
112(d)(3) more than once in issuing or revising MACT standards under 
CAA section 112(d). The commenter pointed out that this proposal is not 
consistent with other RTRs, for which the EPA has taken the position 
that Congress did not intend EPA to establish MACT floors for a second 
time when it revised a standard. The commenter provided the example of 
the Coke Oven RTR rulemaking, in which the EPA stated its rationale for 
CAA section 112(d)(6) not requiring additional floor determinations 
because this would ``effectively convert existing source standards into 
new source standards . . . The EPA sees no indication that section 
112(d)(6) was intended to have this type of inexorable downward 
ratcheting effect.'' The commenter further pointed out litigation 
challenging the Hazardous Organic NESHAP RTR rule, in which the DC 
Circuit Court upheld the position that there should not be an 
inexorable downward ratcheting effect for the MACT floors (NRDC v. EPA, 
529 F.3d 1077, 1083-84 (D.C. Cir. 2008)). The commenter urged the EPA 
to consider the statutorily-prescribed factors in recalculating the 
MACT floor.
    The commenter stated that the EPA is conducting a MACT on MACT 
analysis by recalculating the MACT floor, citing NRDC v. EPA, 529 F.3d 
1077, 1083-84 (D.C. Cir. 2008), where the U.S. Court of Appeals for the 
D.C. Circuit upheld the position that there should not be an inexorable 
downward ratcheting effect for the MACT floors. The commenter agreed 
that the EPA should calculate the floor for phenol and methanol, since 
standards for these HAP were missing from the NESHAP.
    The commenter urged the EPA to retain the 1999 formaldehyde limit, 
saying that the 1999 limit is still the MACT floor and lowering the 
limit would be ``beyond-the-floor'' and would need to be justified 
accordingly. The commenter noted that in the proposal for the 1999 MACT 
rule, the EPA found that the floor for FA lines making both heavy 
density and pipe products was no control. The commenter observed that 
the EPA had also considered controls beyond-the-floor at the time, but 
concluded that the cost effectiveness was unreasonable. According to 
the commenter, nothing has changed since this proposal for FA lines. 
The commenter noted that because no new HAP controls have been added, 
the floor is still no control for these products.
    Response: The EPA does not agree that CAA section 112(d)(6) 
provides the exclusive authority to address MACT standards when a MACT 
determination has already been issued for the source category. The D.C. 
Circuit Court has held that the EPA may permissibly amend improper MACT 
determinations, including amendments to improperly promulgated floor 
determinations, using its authority under CAA sections 112(d)(2) and 
(3). Medical Waste Institute and Energy Recovery Council v. EPA, 645 F. 
3d 420, 425-27 (D.C. Cir. 2011). The absence of standards for these HAP 
is not proper. National Lime Association v. EPA, 233 F. 3d at 633-34; 
see also Medical Waste Institute and Energy Recovery Council v. EPA, 
645 F. 3d at 426 (resetting MACT floor, based on post-compliance data, 
is permissible when originally-established floor was improperly 
established, and permissibility of EPA's action does not turn on 
whether the prior standard was remanded or vacated). Similarly, the 
D.C. Circuit Court's December 9, 2011

[[Page 45311]]

decision in Portland Cement Association v. EPA, 665 F.3d 177, 189 (D.C. 
Cir. 2011) confirms that CAA section 112(d)(6) does not constrain the 
EPA and it may reassess its standards more often, including revising 
existing floors if need be. The commenter is, thus, incorrect in 
arguing that CAA section 112(d)(6) provides the exclusive authority to 
address MACT standards when a MACT determination has already been 
issued for the source category. Further, CAA section 112(d)(6) itself 
provides that the agency must review and revise ``as necessary.'' The 
``as necessary'' language must be read in the context of CAA section 
112(d)(6), which focuses on the review of developments that have 
occurred since the time of the original promulgation of the MACT 
standard and, thus, can be used as an opportunity to correct flaws that 
existed at the time of the original promulgation.
    The EPA is amending the 1999 formaldehyde MACT floor for FA lines 
because the floor was improperly determined. First, the EPA determined 
under this rulemaking that the MACT floor for formaldehyde emissions 
for new FA lines making heavy density products and for new and existing 
FA lines making pipe products were set at the highest measured value 
for each of the subcategories. As such, the 1999 MACT floor for 
formaldehyde was improperly set at a level achievable by all sources 
within the Wool Fiberglass Manufacturing source category and not at a 
level defined by the CAA. Again, as explained in the November 2011 
proposal, when the EPA had in the past (incorrectly) interpreted CAA 
section 112(d) as requiring standards that can be achieved by all 
sources, the D.C. Circuit Court has rejected that interpretation. ``EPA 
may not deviate from section 7413(d)(3)'s requirement that floors 
reflect what the best performers actually achieve by claiming that 
floors must be achievable by all sources using MACT technology.'' 
Cement Kiln Recycling Coalition v. EPA, 255 F.3d at 861. ``EPA may not 
deviate from section 7413(d)(3)'s requirement that floors reflect what 
the best performers actually achieve by claiming that floors must be 
achievable by all sources using MACT technology.'' Cement Kiln 
Recycling Coalition v. EPA, 255 F.3d at 861 (``EPA cannot circumvent 
Cement Kiln's holding that section 7412(d)(3) requires floors based on 
the emission level actually achieved by the best performers (those with 
the lowest emission levels), not the emission level achievable by all 
sources, simply by redefining ``best performing'' to mean those sources 
with emission levels achievable by all sources.'' Sierra Club v. EPA, 
479 F. 3d at 881. (Emphasis in original). In revising the MACT floor 
for formaldehyde, the EPA is ensuring that the floor reflects the 
method established in CAA section 112(d) for establishing the MACT 
floor for major sources of HAP: (1) For existing sources, MACT 
standards must be at least as stringent as the average emissions 
limitation achieved by the best performing 12 percent of existing 
sources (for which the Administrator has emissions information) or the 
best performing five sources for source categories with less than 30 
sources, as is the case here; and (2) for new sources, the MACT 
standards must be at least as stringent as the control level achieved 
in practice by the best controlled similar source (CAA section 
112(d)(3)).
    Second, the EPA determined under this rulemaking that the EPA 
established the MACT floor for the formaldehyde limits for FA lines 
producing light density products (new and existing), automotive 
products (new and existing), and heavy density products (existing) as 
no control (i.e., no limit was established). Therefore, these sources 
of HAP emissions are unregulated under the NESHAP, which is an approach 
soundly rejected by the D.C. Circuit Court in both National Lime 
Association v. EPA, 233 F. 3d at 633-34 and in Portland Cement 
Association v. EPA, 665 F.3d 177, 189 (D.C. Cir. 2011). The EPA 
disagrees with the commenter that the EPA should retain the current 
MACT floor of ``no control'' and that the EPA's recalculating the floor 
represents a level ``beyond the floor.'' Put another way, since the EPA 
did not adopt a proper MACT standard initially, it is not amending a 
MACT standard but adopting one for the first time. Consequently, the 
EPA is not barred from making MACT floor determinations and issuing 
MACT standards for formaldehyde pursuant to CAA sections 112(d)(2) and 
(3).
    Third, the EPA is removing formaldehyde as a surrogate for phenol 
and methanol emissions, as supported by the commenter. The EPA may 
attribute characteristics of a subclass of substances to an entire 
class of substances if doing so is scientifically reasonable. 
Dithiocarbamate Task Force v. EPA, 98 F.3d 1394, 1399 (D.C. Cir. 1996). 
We no longer believe that there is a correlation and, therefore, 
reasonable bases, between formaldehyde and phenol and methanol. Further 
discussion of the EPA's rationale for removing formaldehyde as a 
surrogate for phenol and methanol emissions is provided in the preamble 
to the 2011 proposal (76 FR 72788, 72791, and 72796) for.
    Regarding the comment that this proposal is not consistent with 
other RTRs, we note that in several recent rulemakings we have chosen 
to fix underlying defects in existing MACT standards under CAA sections 
112(d)(2) and (3), provisions that directly govern the initial 
promulgation of MACT standards (see National Emission Standards for 
Hazardous Air Pollutants From Petroleum Refineries, October 28, 2009, 
74 FR 55670; and National Emission Standards for Hazardous Air 
Pollutants: Group I Polymers and Resins; Marine Tank Vessel Loading 
Operations; Pharmaceuticals Production; and the Printing and Publishing 
Industry, April 21, 2011, 76 FR 22566). Regarding the comment that the 
EPA had not provided an explanation or asserted any rational basis for 
choosing to calculate a new MACT floor and standard for formaldehyde, 
in our 2011 proposal, we explained that the D.C. Circuit Court had 
found that we erred in establishing emissions standards for sources of 
HAP in the NESHAP for Brick and Structural Clay Products Manufacturing 
and Clay Ceramics Manufacturing, and, consequently, vacated the rule. 
Sierra Club v. EPA, 479 F. 3d 875 (D.C. Cir. 2007). These errors 
included incorrectly calculating MACT emissions limit, failure to set 
emission limits and failure to regulated processes that emitted HAP. We 
explained that we were taking action to correct similar errors in the 
1999 Wool Fiberglass Manufacturing NESHAP. We identified certain HAP 
that we failed to establish standards for in these rules. We also 
explained that we had not established standards for phenol and methanol 
because they were represented by a surrogate (i.e., formaldehyde).
    With regard to formaldehyde emissions from the Wool Fiberglass 
Manufacturing source category, we explained we were proposing MACT 
limits for existing, new, and reconstructed RS and FA manufacturing 
lines and presented these limits in Tables 4-6 of the 2011 proposal (76 
FR 72791). We also explained that we had a ``clear obligation to set 
emissions standards for each listed HAP.'' National Lime Association v. 
EPA, 233 F. 3d 625, 634 (D.C. Cir. 2000).
4. What is the rationale for our final approach for the formaldehyde, 
methanol, and phenol emission limits?
    As explained elsewhere in this preamble, we are eliminating the 
subcategories for FA bonded lines because we believe that the technical 
or

[[Page 45312]]

design differences that distinguished these subcategories when the 
original rule was developed no longer exist (CAA section 112(d)(1)). We 
are also establishing standards at the MACT floor level of control for 
formaldehyde, methanol, and phenol emissions from FA bonded lines.
    The data available to us at proposal were emissions test data from 
various products within the heavy density products subcategory only, 
and industry indicated that the test data for this subcategory were 
representative of all products manufactured on FA bonded lines. Since 
our various proposals, no additional source test data have been 
provided to support continued subcategorization of FA lines. We, 
therefore, concluded in the various proposals that the limits developed 
for FA lines were representative of all products made on FA lines and 
that further subcategorization was no longer supportable.
    As also explained in our November 25, 2011 proposal, we examined 
the 1999 MACT rule and found that it does not include emissions 
standards for certain products manufactured on FA lines which do not 
fall into the regulated subcategories ``pipe'' and ``heavy density.'' 
\21\ The EPA has a ``clear statutory obligation to set emission 
standards for each listed HAP. Although Sierra Club v. EPA permits the 
Agency to look at technological controls to set emissions standards, it 
does not say that the EPA may avoid setting standards for HAP not 
controlled with technology.'' National Lime Association v. EPA, 233 
F.3d 625, 634 (D.C. Cir. 2000) (internal citation omitted). In our 
review, we found that the foundation supporting the 1999 MACT standard 
for formaldehyde was developed incorrectly. Instead of being based upon 
the emission limit achieved by the average of the best performing 12 
percent of existing sources, it was set at a level that was achievable 
by all existing sources. As explained in our November 25, 2011 
proposal, this approach has been consistently rejected by the D.C. 
Circuit. ``EPA may not deviate from section 7413(d)(3)'s requirement 
that floors reflect what the best performers actually achieve by 
claiming that floors must be achievable by all sources using MACT 
technology.'' Cement Kiln Recycling Coalition v. EPA, 255 F.3d at 861.
---------------------------------------------------------------------------

    \21\ We divided the FA lines into four subcategories: 1. Light 
density, 2. automotive, 3. heavy density and 4. pipe products, but 
set standards for only two subcategories--heavy density (new) and 
pipe product (new and existing). We explained that ``[b]ecause no 
controls are currently used, the MACT floor is no control and 
because the cost effectiveness of additional controls beyond the 
floor is not reasonable, the Agency is not setting emission limits 
for existing FA manufacturing lines producing light-density, 
automotive or heavy-density products or new FA manufacturing lines 
producing light-density or automotive products.'' 61 FR 15239 (March 
31, 1997).
---------------------------------------------------------------------------

    For the reasons provided above, as proposed in the November 2014 
supplemental proposal and in the comment summary and response document 
available in the docket, we are eliminating the subcategories for FA 
lines and finalizing emissions limits at the MACT level of control for 
formaldehyde, phenol, and methanol, as shown in Table 3 of this 
preamble.

D. Work Practice Standards for HCl and HF Emissions From Furnaces in 
the Wool Fiberglass Manufacturing Source Category (Major Sources)

1. What did we propose pursuant to CAA section 112(h) for wool 
fiberglass manufacturing (major sources)?
    In our November 2011 proposal, we proposed emission limits for HF 
and HCl from glass-melting furnaces. In our April 2013 supplemental 
proposal, we proposed work practice standards in lieu of numeric 
emission limits, under CAA section 112(h), in response to comments and 
our evaluation of test data from industry regarding our November 2011 
proposed limits. We explained that in response to comments on the 
November 2011 proposed limits, we re-evaluated test data that we used 
to calculate the MACT floor for the proposed HCl and HF standards and 
found that most of the test data reflected values below the detection 
limit of the test method. Specifically, over 80 percent of the test 
results were values indicating that either HCl or HF, or both 
pollutants, in the exhaust gas stream were below the detection limit of 
the test methods. We, therefore, proposed work practice standards for 
the control of HCl and HF emissions from furnaces. However, in the 2013 
supplemental proposal we did not specifically identify the work 
practice standards. In our November 2014 supplemental proposal, we 
noted that the source of HF and HCl in furnace emissions was cullet 
made from glass used in products such as cathode ray tubes (CRTs), 
microwave ovens, televisions, computer screens, and other electronics. 
Therefore, we proposed work practice standards that would require 
owners and operators of wool fiberglass glass-melting furnaces to 
ensure that the cullet did not contain glass from these types of 
sources either by conducting their own internal inspection and 
recordkeeping program, or by receiving certification from their cullet 
suppliers.
2. How did the work practice standards change for the Wool Fiberglass 
Manufacturing source category since proposal?
    In the November 2014 supplemental proposal, we explained the 
proposed work practice standards for HF and HCl in the preamble, but 
received comment that because the rule language did not accurately 
reflect the preamble language, that it left to interpretation the other 
sources of fluoride in the cullet (such as municipal water supply used 
to wash cullet). We did not intend that interpretation, which would be 
beyond the purposes of the NESHAP. In this final rule, we are 
correcting that deficiency in the November 2014 supplemental proposal, 
withdrawing that previously proposed rule language and specifying in 
the rule text at 40 CFR 63.1382(a)(1)(iii) the correct requirements, as 
previously proposed and as indicated above.
3. What key comments did we receive on the work practice standards, and 
what are our responses?
    We received comments in support of and against our work practice 
standards for HCl and HF emissions from furnaces at wool fiberglass 
facilities. The following is a summary of the key comments received 
regarding the work practice standards and our responses to these 
comments. Additional comments on the work practice standards and our 
responses can be found in the comment summary and response document 
available in the docket for this action (EPA-HQ-OAR-2010-1042).
    Comment: One commenter objected to the EPA establishing work 
practice standards for HCl and HF instead of numerical emission limits 
without first establishing that ``measuring emission levels is 
technologically or economically impracticable'' (Sierra Club v. EPA, 
479 F.3d at 883-84) or that setting work practice standards ``is 
consistent with the provisions of subsection (d) or (f).'' 42 U.S.C. 
7412(h)(1). The commenter understands that 80 percent of emission tests 
were below the detection limit, but contends that this fact 
demonstrates that measuring emissions is difficult, not technologically 
impracticable. The commenter argues that the EPA must explain why it 
cannot use the 20 percent of the tests above that limit, taking the 
detection level into account, to set appropriate emission limits.
    Another commenter requested that the EPA remove all of these 
sources from the calculation for the MACT floor because data that are 
below the minimum detection limit (MDL) of the

[[Page 45313]]

test method (BDL) are unquantifiable and that using BDL data are likely 
to set limits so stringent that the best performing sources cannot even 
meet those limits. The commenter observed that the data for every 
source in the MACT floor ranking is BDL; and the majority of HCl data 
points are BDL. The commenter contended that facilities will have 
difficulty showing compliance with an emission limit that is based on 
data from testing that was BDL. The commenter cited a memorandum from 
RMB Consulting about relying on BDL data.\22\
---------------------------------------------------------------------------

    \22\ RMB Consulting & Research, Inc. Memorandum, Comments on 
Proposed EGU MACT Rule, July 19, 2011, p. 18.
---------------------------------------------------------------------------

    According to the commenter, the EPA should only use values that are 
above the MDL (i.e., actual values) in calculating the MACT floor, and 
that the emissions floor must be determined by quantifiable data. 
According to the commenter, in the Boiler MACT, the EPA reassessed the 
proposed emission limits for dioxins/furans. The commenter noted that, 
as explained by the EPA, a large amount of the emission measurement 
used to set the dioxin/furan limits were below the level that could be 
accurately measured.
    Alternatively, the commenter stated that the EPA could propose a 
work practice standard in order for facilities to show compliance. 
Under the Boiler MACT, the commenter noted that the EPA chose to 
regulate dioxins/furans by using a work practice standard. In that 
case, the commenter stated that 55 percent of facilities tested had 
dioxin/furan emissions below the MDL for EPA Method 23. The commenter 
stated that a work practice standard would allow facilities to decrease 
HCl and HF emissions and be able to show compliance.
    In addition, the commenter stated that the EPA has made no effort 
to take into account reductions achieved as a result of the original 
MACT implementation as part of establishing the MACT floor. If a MACT 
floor is calculated, the commenter contended that it must consider what 
the emissions would have been at the time of the initial MACT 
promulgation in establishing the floor.
    Response: The EPA did not set any standard for HCl and HF in the 
original 1999 MACT rule and is rectifying that deficiency (see National 
Lime Association v. EPA, 233 F. 3d at 634) here by establishing 
standards pursuant to CAA sections 112(d)(2) and (3). Sections 
112(h)(1) and (2)(B) of the CAA indicate that the EPA may adopt a work 
practice standard rather than a numeric standard when ``the application 
of measurement methodology to a particular class of sources is not 
practicable due to technological and economic limitations.'' We 
evaluated test data that we originally used to calculate the MACT floor 
limits for HCl and HF in response to comments such as this one. 
Industry conducted testing in an attempt to obtain data for the acid 
gases HF and HCl, under the terms of the voluntary survey. Emissions 
tests were conducted over three 1-hour test runs, which is, for similar 
industries, sufficient time to detect these acid gases when they are 
emitted. However, we found that most of the test data reflected values 
that were BDL. Specifically, over 80 percent of the test results were 
values BDL for both HF and HCl, indicating that neither HF nor HCl are 
present in measurable amounts in the exhaust gas stream for these 
sources.
    Because of the high percentage on non-detect test runs, we proposed 
work practice standards for HF and HCl in our April 2013 supplemental 
proposal. As explained in our April 2013 supplemental proposal, the EPA 
regards situations where, as here, the majority of measurements are BDL 
as being a situation where measurement is not ``technologically 
practicable'' within the meaning of CAA section 112(h). The EPA also 
believes that unreliable measurements raise issues of practicability, 
feasibility and enforceability. The application of measurement 
methodology in this situation would also not be ``practicable due to . 
. . economic limitation'' within the meaning of CAA section 112(h) 
because it would result in cost expended to produce analytically 
suspect measurements (78 FR 22387).
    As discussed in the preamble to the 2013 supplemental proposal (78 
FR 22387, April 15, 2013), under these circumstances, the EPA does not 
believe that it is technologically and economically practicable to 
measure HCl and HF emissions from this source category. ``[A]pplication 
of measurement methodologies'' (CAA section 112(h)(2)(B)) means more 
than taking a measurement. It must also mean that a measurement has 
some reasonable relation to what the source is emitting (i.e., that the 
measurement yields a meaningful value). That is not the case here and 
the EPA does not believe it reasonable to establish numeric emission 
limits for HCl and HF in this rule. Therefore, in the final rule, we 
are promulgating work practice standards consistent with our April 2013 
supplemental proposal.
    However, we disagree with the comment that in revising or 
promulgating MACT standards, the EPA may not use current test data 
showing that sources may have achieved much lower emissions levels as a 
result of complying with earlier standards. ``EPA acted lawfully, in 
resetting the MACT floors based on post-compliance emissions data.'' 
Medical Waste Institute and Energy Recovery Council v. EPA, 645 F. 3d 
420, 426-27 (D.C. Cir. 2011). In addition to the work practice 
standards in the final rule, control of HCl and HF can also occur as a 
``cobenefit'' of conventional control technologies that have been 
installed for other purposes. These acid gases may be absorbed and 
neutralized when a scrubber is present. We, thus, believe that the work 
practice standards will result in the level of control of the 
exceedingly small amounts of HCl and HF present in wool fiberglass 
furnace emissions achieved by the best performing facilities in the 
source category.
    When testing for indications that a pollutant is emitted by a 
source, if the results are below the detection limits of the method, 
that means that the pollutant was not, in fact, detected. We do not set 
emission limits for all 188 HAP on the list in CAA section 112(b), but 
only for those that are emitted from the processes. We required sources 
to test for HF and HCl, and most (over 80 percent) of sources did not 
detect either of those HAP in their emissions streams. When this is the 
case for over half the sources in the category, we believe it is not 
appropriate to set numerical limits for such pollutants.
    Comment: One commenter stated that glass cullet cannot be 
guaranteed by providers or facilities to be ``free of chloride-, 
fluoride-, and fluorine-bearing constituents,'' as we proposed because 
(1) cullet must be cleaned before use and city supplied water contains 
chloride and fluoride; (2) non-glass materials in cullet (including 
coatings on the glass) contain fluorides or chlorides; (3) recycled 
cullet currently used by the industry may contain trace amounts of 
chlorides and fluorides; and (4) to meet product performance 
requirements, certain glass formulations require glass fibers to 
contain small levels of fluoride. The commenter argued that the 
proposed requirement goes beyond what the industry is currently doing 
to achieve HF and HCl emissions below the detection limit, and to 
achieve the requirement, facilities would need to cease cullet use and 
substitute with other materials.
    The commenter recommended revising the rule to require facilities 
to ``maintain internal documentation that work practices are in place 
that

[[Page 45314]]

maintain low HF and HCl emissions,'' for 5 years, including but not 
limited to the following options:

 Record that cullet is reasonably consistent with previous 
cullet used that has sustained low to non-detect HF and HCl 
emissions; or
 Monitor chloride and/or fluoride content of the cullet or 
finished glass to verify and maintain insignificant trace levels of 
emissions using standard chemical analytic techniques; or
 Use feedstock of raw materials having a 12-month rolling 
average of chloride content at or below 0.1 percent as measured once 
a year using methods similar to ASTM 1152C/1152M or company-
developed methods; or
 Maintain glass formulation records that show that no 
ingredient contains intentionally added chloride; or
 Maintain records from a sampling program, or obtain annual 
certification from cullet providers verifying that the cullet does 
not contain excessive CRT glass; or
 Monitor fluoride content of the finished glass to verify 
that the content is consistent with historic levels of similar glass 
formulations; or
 In lieu of work practices, measure HF and HCl emissions 
during emission testing once every 5 years to confirm that the level 
of HF and HCl emissions is not a statistically significant higher 
level than the level measured for the furnace during the rulemaking 
process.

    The commenter also expressed support for the proposed requirement 
that these records would be maintained for inspection by a permitting 
authority.
    Response: We acknowledge that municipal water can contain chloride 
and fluoride; however, our prohibition on chlorides and fluorides 
pertains to the cullet composition. In the final rule, we are revising 
the proposed work practice standards for the Wool Fiberglass 
Manufacturing source category to address this comment. Specifically, we 
are replacing the proposed requirement that cullet be ``free of 
chloride-, fluoride-, and fluorine-bearing constituents'' with work 
practice standards that require wool fiberglass facilities to maintain 
records from either cullet suppliers or their internal inspections 
showing that cullet is free of the following components that would form 
HF or HCl in the furnace exhaust (i.e., chlorides, fluorides, and 
fluorine): Glass from industrial (also known as continuous strand, or 
textile) fiberglass, CRTs, computer monitors that include CRTs, and 
glass from microwave ovens, televisions or other electronics. Wool 
fiberglass facilities would ensure their feedstock does not contain 
chloride-, fluoride-, or fluorine-bearing cullet by one of two 
approaches: (1) Require the providers of external cullet to verify that 
the cullet does not include waste glass from the chloride-, fluoride- 
or fluorine-bearing sources mentioned above, or (2) Sample their raw 
materials to show the cullet entering the furnace does not contain 
glass from these types of sources. To demonstrate compliance, 
facilities would maintain quality assurance records for raw materials 
and/or records of glass formulations indicating the facility does not 
process fluoride-, fluorine-, or chloride-bearing materials in their 
furnaces, and that they thereby maintain low HF and HCl emissions. 
Major source facilities would be required to make these records 
available for inspection by the permitting authority upon demand.
4. What is the rationale for our final decisions for the work practice 
standards?
    The EPA may adopt a work practice standard rather than a numeric 
standard when ``the application of measurement methodology to a 
particular class of sources is not practicable due to technological and 
economic limitations.'' CAA sections 112(h)(1) and (2)(B). As 
previously explained, in response to comments, we had re-evaluated test 
data that we used to calculate the MACT floor for the proposed HCl and 
HF standards in our November 2011 proposal, and found that most of the 
test data reflected values below the detection limit of the test 
method. Specifically, over 80 percent of the test results were values 
indicating that both HCl and HF in the exhaust gas stream were below 
the detection limit of the methods. We believe such values are not a 
measurement of pollutants but rather an indication that such pollutants 
are not present in measurable concentrations. The EPA regards 
situations where, as here, the majority of measurements are below the 
detection limit as being a situation where measurement is not 
``technologically practicable'' within the meaning of CAA section 
112(h). The EPA also believes that unreliable measurements raise issues 
of practicability, feasibility and enforceability. The application of 
measurement methodology in this situation would also not be 
``practicable due to . . . economic limitation'' within the meaning of 
CAA section 112(h) because it would result in cost expended to produce 
analytically suspect measurements. Therefore, for the reasons provided 
above, in the preambles for the 2013 and 2014 supplemental proposals, 
and in the comment summary and response document available in the 
docket, we are finalizing the work practice standards for HCl and HF 
emissions from furnaces at wool fiberglass manufacturing facilities 
that are major sources.
    As we explained in our November 2014 supplemental proposal (79 FR 
68012 at 68023), in order to protect furnace components, wool 
fiberglass facilities identify, isolate and screen out fluoride- and 
chloride-bearing materials such as glass from industrial (also known as 
continuous strand, or textile) fiberglass, CRTs, computer monitors that 
include CRTs, glass from microwave ovens and glass from televisions. 
The furnace emissions testing shows this is an effective work practice 
to reduce emissions of these acid gases. HF and HCl emissions occur 
when recycled glass from these types of materials enters the external 
cullet stream from the recycling center.
    Owners/operators have two options for work practice standards. The 
first option is to require the providers of the external cullet to 
verify that the cullet does not include waste glass from the chloride-, 
fluoride, or fluorine-bearing sources mentioned above. The second 
option is to sample the raw materials to show the cullet entering the 
furnace does not contain glass from these types of sources.
    We are finalizing work practice standards for the Wool Fiberglass 
Manufacturing source category that require wool fiberglass facilities 
to maintain records from either cullet suppliers or their internal 
inspections showing that the external cullet is free of components that 
can form HF or HCl in the furnace exhaust (i.e., chlorides, fluorides 
and fluorine). Facilities are required to maintain quality assurance 
records for raw materials and/or records of glass formulations 
indicating the facility does not process fluoride-, fluorine-, or 
chloride-bearing materials in their furnaces, and that they thereby 
maintain low HF and HCl emissions. Major source facilities are required 
to make these records available for inspection by the permitting 
authority upon demand. Failure to maintain such records constitutes a 
violation from the requirement.

E. Startup, Shutdown, and Malfunction Provisions for the Wool 
Fiberglass Manufacturing Source Category (Major and Area Sources)

1. What SSM provisions did we propose for the Wool Fiberglass 
Manufacturing source category (major and area sources)?
    In its 2008 decision in Sierra Club v. EPA, 551 F.3d 1019 (D.C. 
Cir. 2008), the DC Circuit Court vacated portions of

[[Page 45315]]

two provisions in the EPA's CAA section 112 regulations governing the 
emissions of HAP during periods of SSM. Specifically, the Court vacated 
the SSM exemption contained in 40 CFR 63.6(f)(1) and 40 CFR 63.6(h)(1), 
holding that under section 302(k) of the CAA, emissions standards or 
limitations must be continuous in nature and that the SSM exemption 
violates the CAA's requirement that some CAA section 112 standards 
apply continuously. We proposed eliminating the SSM exemption in the 
Wool Fiberglass Manufacturing rules for major sources (40 CFR part 63, 
subpart NNN). Consistent with Sierra Club v. EPA, the EPA proposed work 
practice standards in these rules (both 40 CFR part 63, subpart NNN and 
the new 40 CFR part 63, subpart NN) for periods of startup and 
shutdown. We proposed the incorporation of work practice standards at 
startup and shutdown for major sources into the GACT standards for area 
sources. This would mean that gas-fired glass-melting furnaces at area 
sources would have to comply with an alternative compliance provision 
for startup and shutdown that would require sources to keep records 
showing that emissions were routed to the air pollution control devices 
and that these control devices were operated at the parameters 
established during the most recent performance test that showed 
compliance with the applicable emission limits.
    We also provided proposed regulatory text in the General Provisions 
applicability tables in each subpart in several respects consistent 
with vacatur of the SSM exemption. For example, we proposed eliminating 
the incorporation of the General Provisions' requirement in 40 CFR part 
63, subpart NNN that the source develop an SSM plan. We also proposed 
eliminating and revising certain recordkeeping and reporting 
requirements that are related to the SSM exemption.
    In our November 2014 supplemental proposal, we proposed that 
affected sources comply with practices that are used by the best 
performers in the source category (7968016).
2. How did the SSM provisions change for the Wool Fiberglass 
Manufacturing source category (major and area sources)?
    We have not changed any aspect of the proposed SSM provisions for 
40 CFR part 63, subparts NN and NNN since the 2014 supplemental 
proposal.
3. What key comments did we receive on the SSM provisions for the Wool 
Fiberglass Manufacturing source category (major and area sources), and 
what are our responses?
    We received comments for and against the proposed revisions to 
remove the SSM exemptions for the Wool Fiberglass Manufacturing source 
category. The commenters who were against the proposed revisions did 
not provide new information or a basis for the EPA to change the 
proposed provisions and did not provide sufficient information to show 
that facilities cannot comply with the work practice standards during 
periods of startup and shutdown. The comments and our specific 
responses to those comments can be found in the comment summary and 
response document available in the docket for this action (EPA-HQ-OAR-
2010-1042).
4. What is the rationale for our final decisions for the SSM provisions 
for the Wool Fiberglass Manufacturing source category (major and area 
sources)?
    For the reasons provided above, in the preamble for the proposed 
rules, and in the comment summary and response document available in 
the docket, we have removed the SSM exemption from the Wool Fiberglass 
Manufacturing NESHAP for major and area sources; eliminated or revised 
certain recordkeeping and reporting requirements related to the 
eliminated SSM exemption; and removed or modified inappropriate, 
unnecessary, or redundant language in the absence of the SSM exemption. 
We are, therefore, finalizing our proposed determination that 
facilities comply with the work practice standards for periods of 
startup and shutdown for gas-fired glass-melting furnaces in 40 CFR 
part 63, subparts NN and NNN.

F. Other Changes Made to the Wool Fiberglass Manufacturing NESHAP 
(Major and Area Sources)

1. What other changes did we propose for the Wool Fiberglass 
Manufacturing NESHAP (major and area sources)?
a. Electronic Reporting (Wool Fiberglass Manufacturing Major and Area 
Sources)
    As stated in the preamble to the November 2011 proposal, the EPA is 
taking a step to increase the ease and efficiency of data submittal and 
data accessibility. Specifically, the EPA is requiring owners and 
operators of wool manufacturing facilities to submit electronic copies 
of certain required performance test reports. See the discussion in 
section III.G of this preamble for more detail.
b. Test Methods and Testing Frequency (Wool Fiberglass Manufacturing 
Major and Area Sources)
    For both major and area sources, we are finalizing, as proposed, 
the addition of EPA Method 29 for measuring the concentrations of 
chromium.
    For major sources only, we are finalizing requirements for methods 
to measure PM, phenol, formaldehyde, and methanol. We are finalizing 
the requirement, as proposed, to maintain the filter temperature at 248 
 25 degrees Fahrenheit when using Method 5 to measure PM 
emissions from furnaces. We are also amending the NESHAP to allow 
owners or operators to measure PM emissions from furnaces using either 
EPA Method 5 or Method 29.
    We are finalizing, as proposed, the addition of EPA Method 318 for 
measuring the concentration of phenol and alternative test methods for 
measuring the concentration of methanol (EPA Methods 318 or 308). We 
are finalizing, as proposed, the replacement of a minimum sampling time 
of 1 hour with the specification to collect 10 spectra when using EPA 
Method 318. For Method 316, we are finalizing, as proposed, the 
requirement to collect a minimum sampling volume of 2 dscm; however, we 
are not finalizing the proposed minimum sampling run time for EPA 
Method 316 of 2 hours. We are also finalizing editorial changes to the 
performance testing and compliance procedures to specify formaldehyde, 
methanol, phenol, and chromium; and compliance procedures for HF and 
HCl.
    Additionally, we are finalizing, as proposed, the requirement for 
existing sources to conduct performance tests to demonstrate compliance 
with the chromium emission limit for gas-fired furnaces no later than 
July 31, 2017, and annually thereafter. We are also finalizing, as 
proposed, the requirement for existing sources to conduct performance 
tests to demonstrate compliance with the phenol, formaldehyde, and 
methanol emissions limits for FA lines no later than July 31, 2017, and 
every 5 years thereafter. We are finalizing the requirement for new 
sources to conduct performance tests to demonstrate compliance with the 
emissions limits no later than January 25, 2016 or 180 days after 
initial startup, whichever is later. Gas-fired glass-melting furnaces 
must demonstrate compliance with the chromium emission limits annually 
after the first compliance test, and whenever the amount of cullet 
increases from that used in the most recent performance test

[[Page 45316]]

showing compliance with the standard, and all other processes must 
demonstrate compliance with the other emission limits every 5 years 
after the first successful compliance test.
c. Applicability and Compliance Period (Wool Fiberglass Manufacturing 
Major and Area Sources)
    For major sources, we are clarifying, as proposed, that 40 CFR part 
63, NNN applies to FA lines regardless of the product being 
manufactured on the FA line and we are finalizing the compliance period 
of 2 years for existing sources subject to the chromium, formaldehyde, 
HCl, HF, phenol, PM, and methanol emission limits.
    For area sources, we are finalizing, as proposed, the compliance 
period of 2 years for existing sources subject to the chromium emission 
limits.
d. Definitions (Wool Fiberglass Manufacturing Major and Area Sources)
    In this action, we are finalizing, as proposed, definitions that 
apply to both major and area sources. These include a definition for 
``gas-fired glass-melting furnace'', revisions to the definition of 
``new source'', and the notification requirements to update the 
citation to the November 2011 proposal. We are finalizing, as proposed, 
a definition for ``incinerator'' in 40 CFR part 63, NNN (major 
sources).
e. Parameter Monitoring (Wool Fiberglass Manufacturing Major and Area 
Sources)
    For both major and area sources, we are finalizing, as proposed, 
the monitoring requirements for furnaces to provide flexibility in 
establishing appropriate monitoring parameters. We are also requiring 
that facilities operating gas-fired furnaces maintain a 30-day rolling 
average of the percentage of cullet used in the raw materials fed to 
the furnace. To demonstrate compliance with this operating parameter, 
owners or operators must record a daily average value of the percentage 
of cullet used for each operating day and must include all of the daily 
averages recorded during the previous 30 operating days in calculating 
the rolling 30-day average.
    For major sources only, we are also finalizing, as proposed, the 
monitoring requirements for FA lines, to provide flexibility in 
establishing appropriate monitoring parameters.
f. General Provisions Applicability Table (Wool Fiberglass 
Manufacturing Major and Area Sources)
    For major sources, we are also making minor corrections to the 
citations in Table 1 (40 CFR part 63 General Provision applicability 
table) to reflect the final amendments in this action, and the 
revisions that have been made to the General Provisions since 1999.
    For area sources, we are identifying the applicability of part 40 
CFR part 63 General Provisions to subpart NN.
2. How did the provisions regarding these other changes to the Wool 
Fiberglass Manufacturing NESHAP (major and area sources) change since 
proposal?
    We have not made any changes to the proposed provisions for 
electronic reporting; testing methods and frequency; applicability; 
compliance period; definitions; or the General Provision applicability 
table. However, we are revising the parameter monitoring standards of 
40 CFR part 63, subpart NNN to require daily monitoring and recording 
of the percentage of cullet used in the raw materials fed to gas-fired 
glass-melting furnaces and calculation of a rolling 30-day average. The 
parameter monitoring requirements for area sources regulated by subpart 
NN reference the same requirements for major sources in 40 CFR part 63, 
subpart NNN.
3. What key comments did we receive on the other changes to the Wool 
Fiberglass Manufacturing NESHAP (major and area sources), and what are 
our responses?
    We received several comments received regarding electronic 
reporting; testing methods and frequency; applicability; compliance 
period; parameter monitoring; definitions or revisions to the General 
Provisions applicability table. The following is a summary of the key 
comments received regarding the technology review and our responses to 
these comments. Additional comments regarding these changes to the 
NESHAP and our responses can be found in the comment summary and 
response document available in the docket for this action (EPA-HQ-OAR-
2010-1042).
    Comment: For both the major (NNN) and the area (NN) source rules, 
one commenter requested a one-time performance test, or alternatively a 
5-year testing requirement for furnaces, instead of the proposed annual 
performance tests, and asked that sources be allowed to test one 
`representative' furnace instead of having to test every furnace 
subject to the rule. The commenter contended that the EPA's rationale 
that chromium emissions increase with age has no factual basis because 
age is not a causative factor for increased chromium emissions. The 
commenter also pointed out that annual testing is not consistent with 
other MACT (the Hazardous Waste MACT requires testing every 5 years), 
GACT, and NSPS standards, as well as state performance testing 
requirements.
    Response: In our April 2013 supplemental proposal (72 FR 22378), 
the EPA proposed reduced testing requirements for sources with 
emissions that are 75 percent or less of the proposed chromium limit. 
Subsequent to that proposal, the EPA determined that this reduced 
testing frequency would not provide sufficient information to determine 
compliance with the rule for either the plant operator or the EPA 
because chromium emissions increase with furnace age. Refer to the 
EPA's memorandum ``Chromium Emissions and Furnace Age'' (EPA-HQ-OAR-
2010-1042-0332) for a summary of the data and information that EPA used 
to determine that furnace age causes and increase in chromium emissions 
for gas-fired furnaces. Regarding the comment that there are some 
federal and state regulations that require only initial testing, there 
are also federal and state regulations that require annual testing 
(e.g., Portland Cement NESHAP, 40 CFR part 63, subpart LLL). Each 
regulation establishes a testing frequency based on the particular 
characteristics of the industry that will allow the EPA to ensure 
compliance with the standards. We have determined that annual testing 
is appropriate here because the data and the technical literature show 
that a furnace's chromium emissions can increase over a period of a few 
years. The wool fiberglass furnace refractory products degrade due to 
the corrosive and erosive nature of the wool fiberglass furnace 
environment. The wool fiberglass oxyfuel furnaces operate continuously 
over the furnace campaign of 10-12 years, and, according to industry 
statements, as the furnace ages, it loses an average of 20,000 pounds 
annually from the refractory. The pattern of refractory erosion is 
semi-spherical, and the exposed refractory surface area increases 
exponentially because it is constantly being eroded in a curved 3-
dimensional surface pattern. This pattern of furnace refractory wear is 
responsible for the exponential increase in chromium emissions from 
wool fiberglass furnaces. For more information on the relationship 
between

[[Page 45317]]

wool fiberglass furnace age and increasing chromium emissions, see the 
paper ``Mechanisms of Chromium Emissions From Wool Fiberglass 
Furnaces,'' June 2015, in the docket to this rule).
    Comment: One commenter disagreed with the EPA's listing all gas-
fired furnaces for regulation under the area source rule for chromium 
emissions, and asserted that for both the major source rule and the 
area source rule, only certain gas-fired furnaces, oxyfuel furnaces, 
should be regulated for emissions of chromium compounds. The commenter 
suggested that the furnace type and design, not the chromium content of 
furnace refractories, impacts chrome emissions, and only oxyfuel 
furnaces have the specific design features associated with high 
chromium emissions. The commenter listed the following factors as 
responsible for oxyfuel furnaces emitting high hexavalent chromium: 
Higher flame temperature, high bulk wall temperature (oxyfuel 
temperatures peak at 5,000 degrees Fahrenheit; other gas furnaces peak 
at 3,560 degrees Fahrenheit), more chrome refractory brick above glass 
level, higher water vapor concentration, and an oxidizing atmosphere. 
The commenter argued that some of the air-gas furnaces that are not 
oxyfuel have lower surface temperature, and the surface temperature 
above the glass line is the single most influential variable 
influencing hexavalent chromium emissions, not the fuel type. In the 
commenter's opinion, air-gas furnaces should not be regulated in the 
area source rule alongside oxyfuel furnaces.
    The commenter noted that one air-gas furnace was measured emitting 
high levels of chromium compounds, pointing out that it is different 
from other non-oxyfuel air-gas furnaces because it is not standard 
construction and it was at the end of its life. The commenter also 
added that furnace has now been shut down.
    The commenter also indicated that, despite their potential for 
increased chrome emissions, oxyfuel furnaces will continue to be used 
for a number of important reasons, including environmental benefits: 
(1) Oxyfuel furnaces reduce NOX and CO emissions because 
they emit less of these pollutants than does combustion with air, and 
some state and local regulations require reduced NOX 
emissions; (2) oxyfuel firing reduces NOX emissions because 
it does not introduce nitrogen from combustion air into the furnace; 
(3) oxyfuel furnaces use less energy than air-gas furnaces by obviating 
the need to heat nitrogen contained in ambient air and, thus, produce 
less greenhouse gas emissions; and (4) oxyfuel firing also produces a 
reduced volume of flue gases which lowers the gas velocity in the 
furnace combustion zone and lowers the potential to entrain PM.
    Response: We note that this is a comment addressing the furnace 
technology of the wool fiberglass manufacturing industry, and as such 
applies to both major sources (under NNN) and area sources (under NN). 
This comment is addressed here as it first applies to major sources. We 
note that the same principles apply to area sources in this source 
category.
    We disagree with the commenter that air-gas furnaces do not warrant 
a chromium emission limit. Furnace emissions test data were collected 
from all wool fiberglass manufacturing facilities to determine the 
scope and extent of the area source rule limits. The data collected for 
gas-fired furnaces show that oxyfuel furnaces, as the commenter 
correctly points out, have the greatest potential to emit chromium 
compounds, followed by air-gas furnaces. This is because both types of 
gas-fired furnaces operate at elevated temperatures (exceeding 3,000 
degrees Fahrenheit) at and above the level of the glass melt (well in 
excess of the temperature required to liberate and oxidize chromium 
compounds from the chromium refractory of the furnace vessel), are 
heated with natural gas and air (air-gas) or natural gas and oxygen 
(oxyfuel), and are constructed using chromium refractories that are 
capable of resisting the corrosive and erosive wear inherent in wool 
fiberglass furnace environment.
    In addition, as the commenter acknowledged, one air-gas furnace 
constructed using what the commenter described as a ``non-standard 
design,'' measured chromium emissions at levels higher than most of the 
oxyfuel furnaces that were tested. Additionally, according to industry 
comments and the information we collected under the 2012 ICR, all the 
oxyfuel furnaces in the source category are constructed using materials 
similar in type and chromium content to those used to construct the 
highest emitting oxyfuel furnace. There is nothing to prevent a similar 
furnace from being constructed at any site. However, as required, we 
set emissions limits based on the information available to us, and we 
find that both oxyfuel furnaces and air-gas furnaces have greater 
propensity than electric furnaces, by virtue of their construction, 
design, and operating temperatures, to form and emit chromium 
compounds.
    As explained in the preamble to the 2013 supplemental proposal, 
these conditions (high temperatures, available chromium and corrosive 
furnace gases) are factors that contribute to higher chromium emissions 
at wool fiberglass furnaces. As stated by the commenter and by other 
industry representatives, wool fiberglass companies intend to expand 
their use of chromium refractories in furnace designs.
    We disagree with the commenter's view that we should address 
specific facilities only for this regulation. First, we note that 
NESHAP are national rules that apply to source categories rather than 
individual facilities, and while we do have the ability to 
subcategorize by process size, type, or class, we cannot simply target 
an individual facility or facilities. Second, nothing prevents an 
oxyfuel or air-gas furnace similar to the high emitting furnaces to be 
constructed at any existing or new wool fiberglass facility, and it is 
incumbent upon the EPA to prevent the danger to public health that 
would result from such a furnace being located at other sites. As the 
commenter pointed out, ``Despite their potential for increased chrome 
emissions, oxyfuel furnaces will continue to be used for a number of 
important reasons . . ..'', and as discussed in our 2011 proposal, we 
considered the resulting impact if the same furnace were to be 
constructed at any other existing wool fiberglass manufacturing site. 
As documented in our auxiliary risk characterization ``Draft Residual 
Risk Assessment for the Mineral Wool Production and Wool Fiberglass 
Manufacturing Source Categories'' and ``Maximum Predicted HEM-3 Chronic 
Risks (Wool Fiberglass Manufacturing) based on Revised--What If 
Analysis,'' available in the docket for this rulemaking (EPA-HQ-OAR-
2010-1042-0086 and EPA-HQ-OAR-2010-1042-0263, respectively), we found 
that the CertainTeed facility in Athens, Georgia would have a risk of 
400-in-1 million if it were to install a furnace similar to the high-
chromium emitting furnace at Kansas City; and that the Athens, GA 
facility is now an area source that will be subject to the new area 
source standard (having recently phased out the use of phenol/
formaldehyde on the bonded lines). While most wool fiberglass furnaces 
at area sources currently emit chromium at levels well below the 
proposed level of the chromium emission limits, the limits serve as a 
backstop to prevent high emitters from emitting chromium compounds in 
an uncontrolled manner.
    Comment: One commenter expressed concern about the proposed changes 
to Method 5 that reduced the testing temperature of the probe by 100 
degrees to improve the accuracy of the method,

[[Page 45318]]

and whether this change will increase the potential for noncompliance 
with the PM standard. Specifically, the commenter stated that ``what 
once may have passed through the apparatus now may become filterable'' 
and, thus, be counted as PM because of the temperature difference. 
Further, the commenter pointed out that the data used to establish MACT 
for PM were collected at the higher temperature specified in 40 CFR 
63.1385(a)(5) of subpart NNN.
    Response: In the final regulation, we are requiring that owners or 
operators conduct annual emissions tests for chromium, and to test for 
PM emissions every 5 years. To reduce the testing burden on facilities, 
the final rule specifies that owners or operators can measure PM 
emissions from furnaces using either EPA Method 5 or Method 29. 
Consequently, for the years when the facility must test for both 
chromium and filterable PM emissions, owners or operators can use 
Method 29 to obtain measurements for both chromium and filterable PM, 
rather than having to use Methods 5 and 29 separately.
    The 1999 NESHAP specified that owners or operators must use EPA 
Method 5 with the filter temperature maintained at 350  25 
degrees Fahrenheit during for the test. However, Method 29 refers to 
the filter temperature specifications in Method 5 which requires that 
the filter be maintained at 248  25 degrees Fahrenheit 
during testing. To maintain consistency with Method 29, we are amending 
the NESHAP to specify that owners or operators must maintain the filter 
temperature at 248  25 degrees Fahrenheit when using Method 
5 to measure filterable PM concentrations. We acknowledge that 
maintaining the Method 5 filter at 248  25 degrees 
Fahrenheit during testing has the potential capture to more PM than 
would be captured at the higher filter temperature; however, we do not 
believe that the change in filter temperature that we are specifying in 
the final rule will result in wool fiberglass manufacturing facilities 
being in noncompliance with the final PM standards. As noted in the 
2013 supplemental proposal (78 FR 22383), the data submitted to EPA, 
which includes filterable PM data collected using Method 29 and a 
filter temperature operating at 248  25 degrees Fahrenheit, 
show that all gas-fired glass-melting furnaces are currently meeting 
the PM standard, as proposed, of 0.33 pounds of PM per ton of glass 
pulled.
    Comment: One commenter disagreed with the EPA's proposal to reduce 
testing frequency to every 3 years. Due to the past history of unknown 
and unreported chromium emissions, innovation and changes within the 
wool fiberglass industry, the potential for unpredictable changes in 
chromium emissions, and the environmental justice impacts of the 
industry, the commenter requested the EPA to increase the frequency and 
quality of the monitoring and reporting requirements of the rules.
    Response: The EPA is finalizing annual testing, and removing the 
option proposed in 2013 to test every 3 years. The EPA agrees with the 
commenter that annual testing is required due to the fact that emission 
test data show that emissions can significantly increase with furnace 
age. Refer to section III.D.4 of this preamble and to the 2014 
supplemental proposal for further discussion about the EPA's rationale 
for requiring annual testing.
4. What is the rationale for our final decisions regarding these other 
changes to the Wool Fiberglass Manufacturing NESHAP (major and area 
sources)?
    For the reasons provided above and in the preamble for the proposed 
rule, we are finalizing the proposed provisions regarding electronic 
reporting; testing methods and frequency; applicability; compliance 
period; parameter monitoring; definitions; and the General Provision 
applicability table.

VII. What is included in the final Wool Fiberglass Manufacturing Rule 
for area sources?

A. Generally Available Control Technology (GACT) Analysis for Wool 
Fiberglass Manufacturing Area Sources

    We are finalizing, as described in this final action, the chromium 
emission limits for both new and existing gas-fired glass-melting 
furnaces at area sources in the Wool Fiberglass Manufacturing source 
category (see Table 4 in section V.E of this preamble).
1. What did we propose pursuant to CAA sections 112(c)(3) and (d)(5) 
for area sources in the Wool Fiberglass Manufacturing source category?
    We initially proposed GACT standards for area sources in the Wool 
Fiberglass Manufacturing source category on April 15, 2013 (78 FR 
22377). In that proposal, we proposed emission limits for chromium 
(0.00006 pounds per ton of glass pulled) and PM (0.33 pounds per ton of 
glass pulled) for gas-fired glass-melting furnaces at area sources. To 
maintain consistency with the major source rule, we proposed that 
facilities use the same requirements for PM and chromium test methods 
and monitoring, reporting and recordkeeping specified in 40 CFR part 
63, subpart NNN. We also proposed to include an affirmative defense to 
civil penalties for violations of emission limits that are caused by 
malfunctions. In the 2014 supplemental proposal (79 FR 68024), we 
proposed removal of the PM emission limit based on public comments the 
EPA received asserting that setting both PM and chromium limits was not 
necessary. We reviewed the technologies and emissions test data for 
controls that are in place at wool fiberglass furnaces. In some test 
reports, we had both inlet and outlet measurements of both PM and 
chromium. From these tests we saw that, in order for furnaces to meet 
the chromium limit, they would have to control PM, a fraction of which 
is chromium compounds. Because chromium is the specific pollutant of 
concern from the furnace process, and because under the Strategy we may 
either address pollutants of concern through an appropriate surrogate, 
or directly regulate the pollutant of concern, we are setting emission 
limits only for chromium from area sources. However, affected sources 
will still need to achieve PM reductions in order to meet the chromium 
limit. The PM controls in place at gas-fired glass-melting furnaces 
achieve an average efficiency of 98 percent. PM in the furnace exhaust 
includes chromium, and due to the high production rate of the 
continuous furnace process, this can be a significant amount of 
chromium emitted during the course of a year. Source testing conducted 
on two wool fiberglass furnaces at one facility \23\ measured chromium 
at both the inlet and the outlet of the DESP. This test showed chromium 
entering the DESP averaged 1,500 pounds per year. Both PM and chromium 
were measured at the outlet of the DESP: Emissions of PM averaged 1.5 
tons per year, and emissions of chromium averaged 11.4 pounds per year. 
This indicates to us that if sources attempted to remove their PM 
controls they would not be able to meet the chromium limit.
---------------------------------------------------------------------------

    \23\ Testing was conducted at the Certainteed, Inc. facility in 
Mountaintop, PA in December 1991, October 1995, and during several 
tests conducted during the 1998-1999 time period for the state 
compliance reports.
---------------------------------------------------------------------------

    In the 2014 supplemental proposal, we also withdrew our proposal to 
include an affirmative defense to civil penalties for violations of 
emission limits that are caused by malfunctions (79 FR 68015).

[[Page 45319]]

2. How did the GACT analysis change for Wool Fiberglass Manufacturing 
area sources?
    In response to comments on our proposed chromium compounds limits, 
and as discussed in section VI.A of this preamble, we are finalizing a 
chromium compounds emission limit for gas-fired glass-melting furnaces 
for major sources at wool fiberglass manufacturing facilities of 
0.00025 pounds per ton of glass pulled. Consistent with our November 
2014 supplemental proposal, we are not finalizing a PM emissions limit 
for gas-fired glass-melting furnaces at area sources.
    Based on comments we received in response to the November 2014 
supplemental proposal, we again reviewed the cost and control options 
and found using new cost information that the limit as proposed was not 
as cost effective as we initially believed. We determined that it was 
appropriate to modify the proposed limit of 0.00006 pounds per ton of 
glass pulled because the cost effectiveness for the emission reduction 
option was $660,000 per pound of chromium reduced for the raw material 
substitution option, and $620,000 per pound chromium reduced for the 
furnace rebuild option. We believe these costs are not reasonable 
compared to other cases where the EPA has regulated highly toxic 
pollutants, such as hexavalent chromium. We, therefore, reviewed the 
data to determine whether a higher limit than previously proposed would 
be more cost effective while still significantly reducing chromium 
emissions from wool fiberglass gas-fired glass-melting furnaces. We 
found that all gas-fired glass-melting furnaces located at wool 
fiberglass area sources currently emit chromium compounds at rates 
below 0.00025 pounds per ton of glass pulled. These area sources 
together emit 18 pounds of chromium compounds annually.
    We compared the chromium emission reductions that would have 
resulted under the previously proposed emission limit of 0.00006 pounds 
per ton of glass pulled to the reductions that result from the final 
limit of 0.00025 pounds per ton of glass pulled. The limit of 0.00006 
pounds per ton of glass pulled would have resulted in a chromium 
emissions reduction of 8.5 pounds per year at area sources. The final 
limit of 0.00025 pounds per ton of glass pulled does not result in any 
chromium emissions reductions. This is due to the overall low emissions 
of chromium at area sources based on the most recent test data. The 
furnaces at area sources are mostly new furnaces of advanced design. 
While immediate emission reductions would not be realized, this final 
limit sets a backstop so that another high-chromium-emitting, gas-fired 
glass-melting furnace cannot be operated at an area source in this 
industry. This is important for this industry because certain furnaces 
have been shown to emit increasing amounts of chromium as their high-
chromium refractory lining begins to degrade.
    We revised our GACT analysis as two approaches could be used by 
industry to reduce chromium emissions from gas-fired furnaces. One 
approach is to rebuild the furnace at an annualized cost of $462,000 
per year per furnace, and the other is to replace one raw material 
(cullet) with another material (raw minerals), which the industry 
stated would result in lower chromium emissions, at an average cost of 
about $1.3 million per year, depending on the production rate of each 
area source facility. Industry test data show that area sources will 
need to maintain their currently low levels of chromium emissions to 
meet the 0.00025 pounds per ton limit.
    Further, in evaluating available technology at area sources, we 
also considered the furnace technology for gas-fired glass-melting 
furnaces in use at major sources. Under CAA section 112(d)(5), we may 
set the GACT emission limit for area sources that provides for the use 
of generally available control technologies to reduce HAP, and we are 
not precluded from setting the limits for area sources equivalent to 
the limits for major sources. In this instance, as previously 
explained, there are no differences between gas-fired glass-melting 
furnaces in use at area and major sources. Moreover, major sources 
become area sources only by virtue of eliminating formaldehyde from 
their processes. Therefore, we believe that the control measure for 
reducing chromium emissions (i.e., furnace rebuild) used by major 
sources is generally available for area sources, and we are finalizing 
the same emission limit of 0.00025 pounds total chromium per ton of 
glass pulled for gas-fired glass-melting furnaces at area sources, 
under CAA section 112(d)(5).
3. What key comments did we receive on the GACT analysis for Wool 
Fiberglass Manufacturing area sources, and what are our responses?
    We received comments in support of and against our GACT analyses. 
The following is a summary of the key comments received regarding the 
GACT analysis for area sources in the Wool Fiberglass Manufacturing 
source category and our responses to these comments. Additional 
comments on the risk assessment and our responses can be found in the 
comment summary and response document available in the docket for this 
action (EPA-HQ-OAR-2010-1042).
    Comment: One commenter asserted that the EPA has not met procedural 
requirements necessary to regulate area sources under CAA section 112. 
The commenter contended that the EPA does not have the authority to 
list or regulate area sources under CAA section 112 unless the agency 
first finds that the source category presents a threat of adverse 
effects to human health or the environment. The commenter argued that 
the EPA's own risk assessment indicates ``risks due to hexavalent 
chromium and formaldehyde are acceptable.'' In the commenter's opinion 
``all the EPA has done is claim that: (1) Because area sources, like 
major sources, contribute chromium compounds, and (2) because many 
sources that once were major sources have since become area sources, it 
follows that area sources should also be regulated.'' Further, the 
commenter stated that the EPA, in listing area sources, has not 
complied with section 307 of the CAA, which requires the EPA to provide 
to the public a summary of the basis for its decision to list the wool 
fiberglass industry as an area source (i.e., factual data underlying 
the decision, methodology used in obtaining data, and the major legal 
interpretations and policy considerations underlying the proposal). The 
commenter also argued that section 553 of the Administrative Procedures 
Act (APA) mandates a ``notice and comment'' period for the EPA's 
decision to list this industry as an area source due to an ``adverse 
effects'' finding, to give stakeholders an opportunity to comment on 
findings that form the basis of the proposed rulemaking.
    Response: In section II.D of the preamble to our 2013 supplemental 
proposal (78 FR 22375, April 15, 2013), we presented the legal basis 
for our decision to add gas-fired glass-melting furnaces to the list of 
area source categories to be regulated. Sections 112(c) and 112(k) of 
the CAA require the EPA to identify and list the area source categories 
that represent not less than 90 percent of the emissions of the 30 
urban air toxics associated with area sources and subject them to 
standards under the CAA section 112(d). Specifically, sections 
112(c)(3) and 112(k)(3)(B)(ii) of the CAA require the EPA to list area 
sources representing 90 percent or more of emissions of the 30 urban 
HAP regardless of whether the EPA has

[[Page 45320]]

issued an adverse effects finding for each individual area source 
category that contributes to achieving the 90 percent emissions goal.
    As documented in the preamble to the 2013 supplemental proposal (78 
FR 22375, April 15, 2013) and in the memorandum ``Technical 
Memorandum--Emission Standards for Meeting the 90 Percent Requirement 
under Section 112(c)(3) and Section 112(k)(3)(B) of the Clean Air Act'' 
(February 18, 2011; EPA-HQ-OAR-2010-1042-0262), the EPA has achieved 
the 90 percent reduction of national chromium emissions required by the 
Strategy; however, as further stated in the 2013 supplemental proposal, 
nothing in the CAA prevents the agency from going beyond the statutory 
minimum of 90 percent, especially if generally available control 
technology for the source category is available at a reasonable cost. 
Indeed, to date, we have established emission standards for sources 
accounting for almost 100 percent of area source emissions of certain 
urban HAP (e.g., 99 percent of arsenic and beryllium compound 
emissions).
    Regarding the commenter's opinion that the reason the EPA is 
regulating gas-fired glass-melting furnaces as area sources is that 
these sources were once regulated under the NESHAP and that they are 
similar to major sources, the EPA did discuss these facts in the 
preamble to the 2013 supplemental proposal (78 FR 22382, April 15, 
2013). These facts serve to inform the EPA's understanding of this area 
source category, but they are not the reason the EPA is regulating 
these area sources. The EPA is regulating gas-fired furnaces located at 
area sources to comply with the Strategy to address the annual 
emissions of chromium from these sources, as the EPA explained in the 
preamble to the 2013 supplemental proposal (78 FR 22375, April 15, 
2013). In doing so, the EPA is addressing the high levels of chromium 
emissions, in particular hexavalent chromium emissions. As explained in 
the 2013 supplemental proposal preamble, gas-fired glass-melting 
furnaces in this source category have the potential to emit high 
emissions of chromium and to experience emission increases in the 
future:

``. . . we have determined that gas-fired glass-melting furnaces at 
wool fiberglass manufacturing facilities can emit higher levels of 
metal HAP, and also higher than expected levels of chromium than 
electric glass-melting furnaces. This is due to the use of high 
chromium refractories above the glass melt line, and use of these 
refractories is essential to obtain the desired glass-melting 
furnace life. Also, the industry has indicated that the current 
trend is to replace air-gas glass-melting furnaces with oxyfuel 
glass-melting furnaces. Oxyfuel glass-melting furnaces have the 
highest potential for elevated chromium emissions as discussed 
further in section IV.A of this preamble. Accordingly, we believe it 
is appropriate to add gas-fired glass-melting furnaces at wool 
fiberglass manufacturing facilities that are located at area sources 
to the list of area sources regulated in the Urban Air Toxics 
Program.'' (78 FR 22377, April 15, 2013)

    Based on the chromium emissions data for gas-fired glass-melting 
furnaces in the source category available to the EPA, we have 
established that emissions for a furnace can vary according to its 
type, design, operation, and age. The EPA provided an example in the 
preamble to the 2013 supplemental proposal of such variability for the 
CertainTeed's Kansas City facility, the highest-emitting glass-melting 
furnace, for which chromium emissions (93 percent of which were in the 
hexavalent state) increased from 5 pounds per year to 540 pounds per 
year over a period of 7 years (78 FR 22381). These facts demonstrate 
the current and potential future high levels of chromium emitted from 
area sources. Further, the EPA has clearly indicated the high level of 
health risk associated with chromium emissions. In the preamble to the 
2013 supplemental proposal, the EPA stated ``Hexavalent chromium 
inhalation is associated with lung cancer, and EPA has classified it as 
a Class A known human carcinogen, per EPA's classification system for 
the characterization of the overall weight of evidence for 
carcinogenicity'' (78 FR 22374, April 15, 2013).
    Regarding the comment that the EPA has not complied with section 
307 of the CAA because it has not provided to the public a summary of 
the basis for its decision to list gas-fired glass-melting furnaces as 
area sources (i.e., factual data underlying the decision, methodology 
used in obtaining data, and the major legal interpretations and policy 
considerations underlying the proposal), the EPA disagrees. We stated 
our intention in our 2013 supplemental proposal to exceed the 90 
percent threshold for chromium emissions under the Strategy by listing 
gas-fired glass-melting furnaces at area sources (78 FR 22376, April 
15, 2013), and we made clear our intent to regulate chromium due to the 
toxicity of the substance (78 FR 22374, April 15, 2013). We did not 
conduct a health assessment and finding for chromium from this area 
source category because we are not obligated to do so under sections 
112(c)(3), (d)(5), or (k) of the CAA. For example, in our notice of 
revision to the area source category list in 2002 (67 FR 70427, 
November 22, 2002), we listed 23 new source categories as area sources 
to meet or exceed the 90 percent threshold for all 30 HAP addressed by 
the Strategy, and the document included no risk-based rationale for 
listing each source category that exceeded the 90 percent target.
    Further, regarding the comment that the EPA has not complied with 
APA section 553 and section 307 of the CAA, we described our 
methodology for collecting these emissions data, as described in 
section II.E of the 2013 supplemental proposal preamble (78 FR 22376, 
April 15, 2013), and provided an opportunity for comment following that 
supplemental proposal. Regarding the legal basis for our listing area 
sources in section II.D, we presented this information in section II.E 
of the preamble to the 2013 supplemental proposal (78 FR 22376, April 
15, 2013) in compliance with section 307.
    Comment: One commenter objected to the proposed regulation of area 
sources because it is inappropriate and unjustified for the EPA to draw 
firm conclusions at this time about the need to regulate area sources, 
in particular regarding a threat of adverse effects to human health 
from area sources. The commenter contended that the EPA's assessment of 
chromium emissions from the major source category in the 2011 proposal 
was fundamentally flawed and did not support the 2011 proposal, and 
that the EPA admitted in the 2011 proposal preamble that it must 
collect more information before drawing a conclusion regarding the wool 
fiberglass area source category and ``a threat of adverse effects to 
human health or the environment.'' The commenter argued that both of 
these facts reflect on the EPA's readiness to regulate area sources. 
The commenter further observed that the EPA may regulate a category of 
area sources only after making a finding under CAA section 112(c)(3) 
that HAP emissions from such source category present ``a threat of 
adverse effects to human health or the environment'' that warrant 
regulation.
    Another commenter objected to the proposed regulation of area 
sources, given the limited value such a rule would provide. The 
commenter stated that the majority of wool fiberglass manufacturers are 
no longer major sources, observing that the most significant change 
since 1999 is the voluntary substitution of phenol/formaldehyde binders 
with non-phenol/formaldehyde binders, resulting in reduction in HAP 
emissions from this industry of the chief HAP regulated by the Wool 
Fiberglass MACT Standard.

[[Page 45321]]

The commenter suggested that the health risk arising from the 
production of wool fiber glass insulation products has been 
significantly and sufficiently reduced and that any remaining residual 
risk does not justify subjecting the industry to additional regulatory 
requirements in the form of an area source standard.
    Response: As described in the preamble to the April 2013 
supplemental proposal (78 FR 22379), the EPA conducted a CAA section 
114 survey to collect additional test data on chromium emissions from 
glass-melting furnaces, so that the EPA would have test data for all 
glass-melting furnaces. The area source standards proposed in 2013 and 
being finalized in this rulemaking are based on this complete set of 
emission data. Regarding the comments that there is insufficient health 
risk to warrant regulation of area sources and that the EPA is required 
to establish a ``threat of adverse health effects'' to regulate area 
sources, as noted in the comment above, the legal basis for our 
decision to add gas-fired glass-melting furnaces to the list of area 
source categories to be regulated is based on sections 112(c) and 
112(k) of the CAA which require the EPA to identify and list the area 
source categories that represent not less than 90 percent of the 
emissions of the 30 urban air toxics associated with area sources and 
subject them to standards under the CAA section 112(d), and is not 
based on CAA section 112(c)(3).
4. What is the rationale for our final approach for the GACT analysis 
for Wool Fiberglass Manufacturing area sources?
    Because of the considerations discussed above in this preamble, as 
well as in the preamble for the November 2014 supplemental proposal and 
in the comment summary and response document available in the docket 
(EPA-HQ-OAR-2010-1042), we are finalizing revised GACT standards.

B. What are the final requirements for the Wool Fiberglass 
Manufacturing area sources?

    In this action, we are revising the proposed chromium emission 
limit for gas-fired, glass-melting furnaces from 0.00006 to 0.00025 
pounds of total chromium per ton of glass pulled, based on our re-
assessment of emissions data for newly-rebuilt furnaces (see section 
VI.A.2 of this preamble for a discussion of the basis of the revised 
emission limit for chromium compounds). We are also requiring that 
facilities at both major and area sources establish the materials mix, 
including the percentages of raw minerals and cullet used in gas-fired 
glass-melting furnaces during the performance test conducted to 
demonstrate compliance with the chromium emission limit. The source 
must maintain the percentage of cullet in the raw material mixture at 
or below the level established during the most recent performance test 
showing compliance with the standard. If the gas-fired glass-melting 
furnace uses 100-percent cullet during the performance test and is in 
compliance with the chromium emissions limit, then the source is not 
required to monitor cullet usage. Other requirements for Wool 
Fiberglass Manufacturing area sources, including startup and shutdown, 
compliance dates, test methods, monitoring, recordkeeping, and 
reporting are the same requirements as those specified for major source 
facilities in 40 CFR part 63, subpart NNN. Therefore, 40 CFR part 63, 
subpart NN cites 40 CFR part 63, subpart NNN, for these requirements.

C. What are the effective and compliance dates of the standards for 
Wool Fiberglass Manufacturing area sources?

    The GACT standards for gas-fired glass-melting furnaces located at 
Wool Fiberglass Manufacturing area sources being promulgated in this 
action are effective on July 29, 2015. The compliance date for existing 
sources is July 31, 2017. New sources must comply with the all of the 
standards immediately upon the effective date of the standard, July 29, 
2015, or upon initial startup, whichever is later.
    The effective and compliance dates finalized in this action are 
consistent with the dates we presented in the 2014 supplemental 
proposal.

D. What are the requirements for submission of performance test data to 
the EPA for Wool Fiberglass Manufacturing area sources?

    The requirements for electronic reporting of performance test data 
for wool fiberglass manufacturing area sources are the same as the 
requirements for the mineral wool production source category. See 
section III.G of this preamble for a description of the requirements.

VIII. Summary of Cost, Environmental and Economic Impacts and 
Additional Analyses Conducted

A. What are the affected facilities?

1. Mineral Wool Production Source Category
    We estimate that there are eight mineral wool facilities that are 
major sources and, therefore, would be subject to the final NESHAP 
provisions.
2. Wool Fiberglass Manufacturing Source Category (Major and Area 
Sources)
    We estimate that there are 30 facilities in this source category 
(10 major sources and 20 area sources). Based on the responses to the 
CAA section 114 ICR, we believe that two of the 10 wool fiberglass 
manufacturing facilities that are major sources would rebuild two 
furnaces before the end of their operational lifecycles. We believe 
that all furnaces at area sources can comply with the final chromium 
emission limit without rebuilding before the end of their operational 
lifecycles.

B. What are the air quality impacts?

1. Mineral Wool Production Source Category
    Emissions of HAP from mineral wool production facilities have 
declined over the last decade as a result of federal and state rules 
and the industry's own initiatives. The amendments we are finalizing in 
this action would maintain COS, formaldehyde, phenol, and methanol 
emissions at their current low levels.
2. Wool Fiberglass Manufacturing Source Category (Major and Area 
Sources)
    We expect that these final RTR amendments would result in 
reductions of 524 pounds of chromium compounds, 490 pounds of which is 
in the hexavalent form. Available information indicates that all 
affected facilities will be able to comply with the final work practice 
standards for HF and HCl without additional controls, and that there 
will be no measurable reduction in emissions of these gases.
    Also, we anticipate that there will be continued reductions in PM 
emissions due to these final PM standards, which all sources currently 
are meeting due to the use of well-performing PM controls. Industry 
comments, statements, and sources in the technical literature indicate 
that as sources of industrial oxygen become available in areas 
proximate to wool fiberglass facilities, such sources will convert 
their existing furnaces to oxyfuel technology. As described in the 
``Mechanisms of Chromium Emissions From Wool Fiberglass Glass-Melting 
Furnaces,'' June 2015, PM emissions are greatly reduced compared to 
electric furnaces and air-gas furnace technology.
    Indirect or secondary air quality impacts include impacts that will 
result from the increased electricity usage

[[Page 45322]]

associated with the operation of control devices. We do not anticipate 
significant secondary impacts from the final amendments to the Wool 
Fiberglass Manufacturing MACT.

C. What are the cost impacts?

1. Mineral Wool Production Source Category
    All lines currently in operation can meet the emission limits 
finalized in this action without installing new control equipment or 
using different input materials. The total annualized costs for these 
final amendments are estimated at $48,800 (2013 dollars) for additional 
testing and monitoring.
2. Wool Fiberglass Manufacturing Source Category (Major and Area 
Sources)
    The capital costs for each facility were estimated based on the 
ability of each facility to meet the final emissions limits for PM, 
chromium compounds, formaldehyde, phenol, and methanol. The memorandum, 
``Cost Impacts of the Final NESHAP RTR Amendments for the Wool 
Fiberglass Manufacturing Source Category,'' includes a complete 
description of the cost estimate methods used for this analysis and is 
available in the docket.
    There are a total of eight gas-fired glass-melting furnaces located 
at five major source facilities. Compliance testing is $10,000 per 
furnace, resulting in total testing costs for glass-melting furnaces of 
$80,000. At this time, there are two facilities with a total of two 
gas-fired glass-melting furnaces that do not meet the final emissions 
limit for chromium compounds. We anticipate that these facilities would 
opt to reduce the operational lifecycle for both of the gas-fired 
glass-melting furnaces.
    Based on the public comments and information received in response 
to November 2014 supplemental proposal, we revised our cost estimate 
from reducing the operational furnace lifecycle (from 10 to 7 years), 
to a cost estimate for rebuilding gas-fired glass-melting furnaces. In 
this cost estimate, we included the cost of transferring production to 
another facility while the furnace is being rebuilt.
    For major sources, the estimated capital cost of rebuilding the 
furnace is $10.7 million per furnace with a total annualized cost of 
$462,000 per furnace.
    Two major source facilities operate 13 FA manufacturing lines, and, 
therefore, would incur testing costs (annualized cost of $10,400 in 
2013 dollars). The total annualized costs for the final amendments to 
the Wool Fiberglass Manufacturing NESHAP for major sources are 
estimated at $1.01 million (2013 dollars).
    Of the 20 area source facilities, five facilities operate a total 
of eight gas-fired glass-melting furnaces. Under these final 
amendments, none of the area source wool fiberglass facilities will 
incur any capital costs to comply with the final chromium compounds 
emissions limit. Five area source facilities would be subject to new 
costs for compliance testing on gas-fired glass-melting furnaces, which 
will total $80,000 annually (2013 dollars).

D. What are the economic impacts?

1. Mineral Wool Production Source Category
    As noted in the November 2014 supplemental proposal (79 FR 68025), 
we performed an economic impact analysis for mineral wool consumers and 
producers nationally. The impacts to producers affected by this final 
rule are annualized costs of less than 0.01 percent of their revenues, 
using 2013 year revenue data to be consistent with the cost year for 
our analysis. Prices and output for mineral wool products should 
increase by no more than the impact of cost to revenues for producers; 
thus, mineral wool prices should increase by less than 0.01 percent. 
Hence, the overall economic impact of this final rule would be 
negligible to the affected industries and their consumers. For more 
information, please refer to the ``Economic Impact and Small Business 
Analysis'' for this final rulemaking that is in the docket (EPA-HQ-OAR-
2010-1042).
2. Wool Fiberglass Manufacturing Source Category (Major and Area 
Sources)
    We performed an economic impact analysis for wool fiberglass 
consumers and producers nationally, using the annual compliance costs 
estimated for both the RTR and area source final rules. The impacts to 
producers affected by this final rule are annualized costs of less than 
0.01 percent of their revenues, using 2013 revenue data to be 
consistent with the cost year for our analysis. Prices and output for 
wool fiberglass products should increase by no more than the impact on 
cost to revenues for producers; thus, wool fiberglass prices should 
increase by less than 0.01 percent. Hence, the overall economic impact 
of this final rule would be negligible on the affected industries and 
their consumers. For more information, please refer to the ``Economic 
Impact and Small Business Analysis'' for this final rulemaking that is 
in the docket (EPA-HQ-OAR-2010-1042).

E. What are the benefits?

1. Mineral Wool Production Source Category
    The amendments we are finalizing in this action will maintain the 
reductions in COS, formaldehyde, phenol, and methanol emissions that 
the industry has achieved over time at their currently low levels.
2. Wool Fiberglass Manufacturing Source Category (Major and Area 
Sources)
    We estimate that this action will achieve HAP emissions reduction 
of 524 pounds per year of chromium compounds from the Wool Fiberglass 
Manufacturing source category. The final standards will result in 
significant reductions in the actual and MACT-allowable emissions of 
chromium compounds and will reduce the actual and potential cancer 
risks and non-cancer health effects due to emissions of chromium 
compounds from this source category.
    In the November 2014 supplemental proposal (79 FR 68026), we 
estimated that the proposed emission limits for FA and RS manufacturing 
lines would reduce organic HAP emissions by 123 tons per year. Based on 
the available data, we believe that all FA lines currently meet the 
final emission limits; therefore, all of the emission reductions of 
organic HAP presented in the 2014 supplemental proposal were attributed 
to RS lines. As discussed in section V.H of this preamble, we are not 
establishing emission limits for RS manufacturing lines in this final 
action. Consequently, the emissions limits for formaldehyde, methanol, 
and phenol finalized in this action do not achieve reductions of 
organic HAP; however, the emission limits codify the reductions in 
organic HAP from FA lines that have been achieved by the industry since 
the 1999 NESHAP was promulgated. We have issued a CAA section 114 ICR 
to obtain process and emissions data for RS manufacturing lines and we 
will evaluate RTR limits for these sources, based on the CAA section 
114 ICR data, at a future date.

F. What analysis of environmental justice did we conduct?

    The EPA is making environmental justice part of its mission by 
identifying and addressing, as appropriate, disproportionately high and 
adverse human health or environmental effects of its programs, policies 
and activities on minority populations and low income populations in 
the United States. The EPA has established policies regarding the 
integration of

[[Page 45323]]

environmental justice into the agency's rulemaking efforts, including 
recommendations for the consideration and conduct of analyses to 
evaluate potential environmental justice concerns during the 
development of a rule.
    Following these recommendations, to gain a better understanding of 
the source category and near source populations, the EPA conducted a 
proximity analysis for mineral wool production and wool fiberglass 
manufacturing facilities prior to proposal to identify any 
overrepresentation of minority, low income, or indigenous populations. 
This analysis gives an indication of the prevalence of sub-populations 
that may be exposed to air pollution from the sources.
    The EPA also conducted a risk-based socio-economic analysis for 
populations living near wool fiberglass facilities titled ``Risk and 
Technology Review--Analysis of Socio-Economic Factors for Populations 
Living Near Wool Fiberglass Facilities,'' which is available in the 
docket. The analysis indicated that 1,207,000 individuals living within 
50 km of the wool fiberglass facilities have a cancer risk of 1-in-1 
million or greater due to emissions from wool fiberglass facilities. 
The specific demographic results indicate that the percentage of 
minority population potentially impacted by emissions from wool 
fiberglass facilities (i.e., within 50 km) is greater than the national 
minority percentage (44 percent for the source category compared to 28-
percent nationwide). Furthermore, other demographic groups with source 
category percentages greater than the corresponding national percentage 
include: The population over 25 without a high school diploma (18 
percent compared to 15 percent); the population from 18 to 64 years of 
age (66 percent compared to 63 percent), and the population below the 
poverty level (15 percent compared to 14 percent). The other 
demographic categories potentially impacted by emissions from wool 
fiberglass facilities (i.e., African American, Native American, ages 
less than 18, and ages 65 and up) are less than or equal to the 
corresponding national percentage.
    The EPA's integration of environmental justice into the agency's 
rulemaking efforts was also thoroughly demonstrated by EPA's Region 7 
response to emissions data obtained through this rulemaking. Region 7 
proactively engaged the local community and identified potential 
environmental concerns; conducted air monitoring and modeling; and 
opened lines of communication and launched several opportunities for 
the community to voice concerns, ask questions, and receive additional 
information. Additionally, EPA Headquarters and Region 7 worked 
together to provide resources for communities, as well as to ensure 
that feedback received from the Region 7 communities was being 
considered in this rulemaking.
    Through our analyses, the EPA has determined that these final rules 
for 40 CFR part 63, subparts NN, DDD, and NNN will not have 
disproportionately high and adverse human health or environmental 
effects on minority, low income, or indigenous populations. 
Additionally, the final changes to the NESHAP for Mineral Wool 
Production and Wool Fiberglass Manufacturing source categories increase 
the level of environmental protection for all affected populations by 
reducing emissions of chromium compounds by over 524 pounds per year 
and will not cause any disproportionately high and adverse human health 
or environmental effects on any population, including any minority, low 
income, or indigenous populations. Our demographic analysis shows that 
disproportionately impacted minority areas will benefit from the lower 
emissions. Further details concerning this analysis are presented in 
the memorandum titled, ``Updated Environmental Justice Review: Mineral 
Wool Production and Wool Fiberglass Manufacturing RTR,'' a copy of 
which is available in the dockets for this action.

G. What analysis of children's environmental health did we conduct?

    As part of the health and risk assessments, risk-based demographic 
analysis conducted for this action, risks to infants and children were 
assessed. This analysis is documented in the following memoranda which 
are available in the dockets for this action:

     ``Residual Risk Assessment for the Mineral Wool 
Production and Wool Fiberglass Manufacturing Source Categories in 
Support of the June 2015 Final Rule''
     ``Risk and Technology Review--Analysis of Socio-
Economic Factors for Populations Living Near Wool Fiberglass 
Facilities''

    The results of the risk-based socio-economic analysis for 
populations living near wool fiberglass facilities indicates that there 
are 1,207,000 individuals living within 50 km of the wool fiberglass 
facilities have a cancer risk of 1-in-1-million or greater (based on 
actual emissions). The distribution of the population with risks above 
1-in-1 million is 24 percent for ages 0 to 17, 66 percent for ages 18 
to 64, and 10 percent for ages 65 and up. Children ages 0 to 17 also 
constitute 24 percent of the population nationwide. Therefore, the 
analysis shows that actual emissions from wool fiberglass facilities do 
not have a disproportionate impacts on children ages 0 to 17.
    The results of the demographic analysis show that the average 
percentage of children 17 years and younger in close proximity to 
mineral wool production and wool fiberglass manufacturing facilities is 
similar to the percentage of the national population in this age group. 
The difference in the absolute number of percentage points of the 
population 17 years and younger from the national average indicates a 
7-percent over-representation near mineral wool production and wool 
fiberglass manufacturing facilities.
    Consistent with the EPA's ``Policy on Evaluating Health Risks to 
Children'', we conducted inhalation and multipathway risk assessments 
for the Mineral Wool Production and Wool Fiberglass Manufacturing 
source categories considering risk to infants and children.\24\ 
Children are exposed to chemicals emitted to the atmosphere via two 
primary routes: Either directly via inhalation, or indirectly via 
ingestion or dermal contact with various media that have been 
contaminated with the emitted chemicals. The EPA considers the 
possibility that children might be more sensitive than adults might be 
to toxic chemicals, including chemical carcinogens.
---------------------------------------------------------------------------

    \24\ Policy on Evaluating Health Risks to Children, U.S. 
Environmental Protection Agency, Washington, DC. May 2014. Available 
at http://www2.epa.gov/sites/production/files/2014-05/documents/1995_childrens_health_policy_statement.pdf.
---------------------------------------------------------------------------

    For our multipathway screening assessment (i.e., ingestion), we 
assessed risks for adults and various age groups of children to 
determine what age group was most at risk for purposes of developing 
the screening/emission threshold for each persistent and 
bioaccumulative--HAP (PB-HAP). Childrens' exposures are expected to 
differ from exposures of adults due to differences in body weights, 
ingestion rates, dietary preferences, and other factors. It is 
important, therefore, to evaluate the contribution of exposures during 
childhood to total lifetime risk using appropriate exposure factor 
values, applying age-dependent adjustment factors (ADAF) as 
appropriate. The EPA developed a health protective exposure scenario 
whereby the receptor, at various lifestages, receives ingestion 
exposure via both the farm food chain and the fish ingestion pathways.
    Based on the analyses described above, the EPA has determined that 
the

[[Page 45324]]

changes to these rules, which will reduce emissions of chromium 
compounds by over 524 pounds per year, will lead to reduced risk to 
children and infants. The final amendments will also codify the 
reductions in emissions (COS, formaldehyde, phenol, and methanol from 
mineral wool facilities, and formaldehyde, methanol, and phenol from 
wool fiberglass facilities) that the industries have achieved since the 
NESHAP for the respective source categories were promulgated in 1999.

IX. Statutory and Executive Order Reviews

    Additional information about these statutes and Executive Orders 
can be found at http://www2.epa.gov/lawsregulations/laws-and-executive-order.

A. Executive Orders 12866: Regulatory Planning and Review and Executive 
Order 13563: Improving Regulation and Regulatory Review

    This action is not a significant regulatory action and was, 
therefore, not submitted to the Office of Management and Budget (OMB) 
for review.

B. Paperwork Reduction Act (PRA)

    The information collection activities in these rules have been 
submitted for approval to the OMB under the PRA. The ICR document that 
the EPA prepared for the Mineral Wool Production source category has 
been assigned EPA ICR number 1799.06. The ICR document that the EPA 
prepared for the Wool Fiberglass Manufacturing source category has been 
assigned EPA ICR number 1160.10. You can find a copy of these ICRs in 
the dockets for these rules, and they are briefly summarized here. The 
information collection requirements are not enforceable until OMB 
approves them.
    The information requirements in these rulemakings are based on the 
notification, recordkeeping and reporting requirements in the NESHAP 
General Provisions (40 CFR part 63, subpart A), which are mandatory for 
all operators subject to national emission standards. These 
notifications, reports and records are essential in determining 
compliance, and are specifically authorized by CAA section 114 (42 
U.S.C. 7414).
    Mineral Wool Production source category:
    Respondents/affected entities: Existing, new, or reconstructed 
mineral wool production facilities that are major sources.
    Respondent's obligation to respond: Mandatory (42 U.S.C 7414).
    Estimated number of respondents: 8.
    Frequency of response: Annual.
    Total estimated burden: 123 hours (per year). Burden is defined at 
5 CFR 1320.3(b).
    Total estimated cost: $25,150 (per year), includes $0 annualized 
capital or operation and maintenance costs.
    Wool Fiberglass Manufacturing source category (major sources):
    Respondents/affected entities: Existing, new, or reconstructed wool 
fiberglass manufacturing facilities that are major sources.
    Respondent's obligation to respond: Mandatory (42 U.S.C 7414).
    Estimated number of respondents: 10.
    Frequency of response: Annual.
    Total estimated burden: 156 hours (per year). Burden is defined at 
5 CFR 1320.3(b).
    Total estimated cost: $46,142 (per year), includes $0 annualized 
capital or operation & maintenance costs.
    Wool Fiberglass Manufacturing source category (area sources):
    Respondents/affected entities: Existing, new, or reconstructed gas-
fired glass-melting furnaces at a wool fiberglass manufacturing 
facility that are located at a plant site that is an area source.
    Respondent's obligation to respond: Mandatory (42 U.S.C 7414).
    Estimated number of respondents: 5.
    Frequency of response: Annual.
    Total estimated burden: 78 hours (per year). Burden is defined at 5 
CFR 1320.3(b).
    Total estimated cost: $32,334 (per year), includes $0 annualized 
capital or operation and maintenance costs.
    An agency may not conduct or sponsor, and a person is not required 
to respond to, a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for the 
EPA's regulations in 40 CFR are listed in 40 CFR part 9. When OMB 
approves this ICR, the Agency will announce that approval in the 
Federal Register and publish a technical amendment to 40 CFR part 9 to 
display the OMB control number for the approved information collection 
activities contained in this final rule.

C. Regulatory Flexibility Act (RFA)

    I certify that this action will not have a significant economic 
impact on a substantial number of small entities under the RFA. Five of 
the eight mineral wool production parent companies affected in the 
final rule are considered to be small entities per the definition 
provided in this section. There are no small businesses in the Wool 
Fiberglass Manufacturing source category. We estimate that these final 
rules will not have a significant economic impact on any of those 
companies.
    While there are some costs imposed on affected small businesses as 
a result of these rulemakings, the costs associated with this action 
are less than the costs associated with the limits proposed on November 
25, 2011. Specifically, the cost to small entities in the Mineral Wool 
Production source category due to the changes in COS, HF, and HCl are 
lower as compared to the limits proposed on November 25, 2011, and 
April 15, 2013. None of the five small mineral wool parent companies is 
expected to have an annualized compliance cost of greater than 1 
percent of its revenues. All other affected parent companies are not 
small businesses according to the SBA small business size standard for 
the affected NAICS code (NAICS 327993). Therefore, we have determined 
that the impacts for this final rule do not constitute a significant 
economic impact on a substantial number of small entities.
    Although these final rules would not have a significant economic 
impact on a substantial number of small entities, the EPA nonetheless 
has tried to mitigate the impact that these rules would have on small 
entities. The actions we took to mitigate impacts on small businesses 
include less frequent compliance testing for the entire mineral wool 
industry and subcategorizing the Mineral Wool Production source 
category in developing the proposed COS, HF and HCl emissions limits. 
For more information, please refer to the economic impact and small 
business analysis that is in the docket.

D. Unfunded Mandates Reform Act (UMRA)

    This action does not contain an unfunded mandate of $100 million or 
more as described in UMRA, 2 U.S.C. 1531-1538, and does not 
significantly or uniquely affect small governments. The action imposes 
no enforceable duty on any state, local, or tribal governments, or on 
the private sector.

E. Executive Order 13132: Federalism

    This action does not have federalism implications. It will not have 
substantial direct effects on the states, on the relationship between 
the national government and the states, or on the distribution of power 
and responsibilities among the various levels of government.

[[Page 45325]]

F. Executive Order 13175: Consultation and Coordination With Indian 
Tribal Governments

    This action does not have tribal implications, as specified in 
Executive Order 13175. These final rules impose requirements on owners 
and operators of specified area and major sources, and not tribal 
governments. There are no wool fiberglass manufacturing facilities or 
mineral wool production facilities owned or operated by Indian tribal 
governments. Thus, Executive Order 13175 does not apply to this action.

G. Executive Order 13045: Protection of Children From Environmental 
Health Risks and Safety Risks

    This action is not subject to Executive Order 13045 because it is 
not economically significant as defined in Executive Order 12866, and 
because the EPA does not believe the environmental health or safety 
risks addressed by this action present a disproportionate risk to 
children. This action's health and risk assessments are contained in 
sections IV.A, VI.A, VIII.F, VIII.G of this preamble and in the 
``Residual Risk Assessment for the Mineral Wool Production and Wool 
Fiberglass Manufacturing Source Categories'' memorandum available in 
the dockets for this rulemaking.

H. Executive Order 13211: Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution or Use

    This action is not subject to Executive Order 13211 because it is 
not a significant regulatory action under Executive Order 12866.

I. National Technology Transfer and Advancement Act (NTTAA)

    This rulemaking involves technical standards. Therefore, the EPA 
conducted searches for the Wool Fiberglass Manufacturing Area Source 
NESHAP through the Enhanced National Standards Systems Network (NSSN) 
Database managed by the American National Standards Institute (ANSI). 
We also contacted voluntary consensus standards (VCS) organizations and 
accessed and searched their databases.
    As discussed in the November 2014 supplemental proposal (79 FR 
68029), under 40 CFR part 63 subpart DDD, we conducted searches for EPA 
Methods 5, 318, and 320 of 40 CFR part 60, Appendix A. Under 40 CFR 
part 63, subpart NNN, we conducted searches for EPA Methods 5, 318, 
320, 29, and 0061 of 40 CFR part 60, Appendix A. Under 40 CFR part 63, 
subpart NN, we conducted searches for EPA Methods 5 and 29. These 
searches did not identify any VCS that were potentially applicable for 
this rule in lieu of EPA reference methods. The EPA solicited comments 
on VCS and invited the public to identify potentially-applicable VCS; 
however, we did not receive comments regarding this aspect of 40 CFR 
part 63, subparts NN, DDD, or NNN.

J. Executive Order 12898: Federal Actions To Address Environmental 
Justice in Minority Populations and Low-Income Populations

    The EPA believes the human health or environmental risk addressed 
by this action will not have potential disproportionately high and 
adverse human health or environmental effects on minority, low-income, 
or indigenous populations because it does not affect the level of 
protection provided to human health or the environment. As explained in 
the November 2014 supplemental proposal (79 FR 68029), the EPA 
determined that this final rule will not have disproportionately high 
and adverse human health or environmental effects on minority or low-
income populations, because it increases the level of environmental 
protection for all affected populations without having any 
disproportionately high and adverse human health or environmental 
effects on any population, including any minority or low-income 
population. Further details concerning this analysis are presented in 
the memorandum titled, ``Updated Environmental Justice Review: Mineral 
Wool Production and Wool Fiberglass Manufacturing RTR'', a copy of 
which is available in the dockets for this action. Additionally, the 
EPA engaged meaningfully with communities throughout this rulemaking 
process, to help them engage in the rulemaking process and to get their 
feedback on the proposed rulemaking. Also, EPA worked closely with 
Region 7, to ensure that communities that raised concerns by the 
sectors covered in this rulemaking, were being adequately engaged 
throughout this process.

K. Congressional Review Act (CRA)

    This action is subject to the CRA, and the EPA will submit a rule 
report to each House of the Congress and to the Comptroller General of 
the United States. This action is not a ``major rule'' as defined by 5 
U.S.C. 804(2).

List of Subjects in 40 CFR Part 63

    Environmental protection, Administrative practice and procedures, 
Air pollution control, Hazardous substances, Incorporation by 
reference, Intergovernmental relations, Mineral wool production, 
Reporting and recordkeeping requirements, Wool fiberglass 
manufacturing.

    Dated: June 25, 2015.
Gina McCarthy,
Administrator.

    For the reasons stated in the preamble, part 63 of title 40, 
chapter I, of the Code of Federal Regulations is amended as follows:

PART 63--NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS 
FOR SOURCE CATEGORIES

0
1. The authority citation for part 63 continues to read as follows:

    Authority: 42 U.S.C. 7401 et seq.

0
2. Subpart NN is added to part 63 to read as follows:
Subpart NN--National Emission Standards for Hazardous Air Pollutants 
for Wool Fiberglass Manufacturing at Area Sources
Sec.
63.880 Applicability.
63.881 Definitions.
63.882 Emission standards.
63.883 Monitoring requirements.
63.884 Performance test requirements.
63.885 Test methods and procedures.
63.886 Notification, recordkeeping, and reporting requirements.
63.887 Compliance dates.
63.888 Startups and shutdowns.
63.889-63.899 [Reserved]
Table 1 to Subpart NN of Part 63-- Applicability of General 
Provisions (40 CFR part 63, Subpart A) to Subpart NN

Subpart NN--National Emission Standards for Hazardous Air 
Pollutants for Wool Fiberglass Manufacturing at Area Sources

Sec.  63.880  Applicability.

    (a) The requirements of this subpart apply to the owner or operator 
of each wool fiberglass manufacturing facility that is an area source 
or is located at a facility that is an area source.
    (b) The requirements of this subpart apply to emissions of chromium 
compounds, as measured according to the methods and procedures in this 
subpart, emitted from each new and existing gas-fired glass-melting 
furnace located at a wool fiberglass manufacturing facility that is an 
area source.
    (c) The provisions of subpart A of this part that apply and those 
that do not apply to this subpart are specified in Table 1 to this 
subpart.
    (d) Gas-fired glass-melting furnaces that are not subject to 
subpart NNN of this part are subject to this subpart.

[[Page 45326]]

    (e) Gas-fired glass-melting furnaces using electricity as a 
supplemental energy source are subject to this subpart.

Sec.  63.881  Definitions.

    Terms used in this subpart are defined in the Clean Air Act, in 
Sec.  63.2, or in this section as follows:
    Bag leak detection system means systems that include, but are not 
limited to, devices using triboelectric, light scattering, and other 
effects to monitor relative or absolute particulate matter emissions.
    Gas-fired glass-melting furnace means a unit comprising a 
refractory vessel in which raw materials are charged, melted at high 
temperature using natural gas and other fuels, refined, and conditioned 
to produce molten glass. The unit includes foundations, superstructure 
and retaining walls, raw material charger systems, heat exchangers, 
exhaust system, refractory brick work, fuel supply and electrical 
boosting equipment, integral control systems and instrumentation, and 
appendages for conditioning and distributing molten glass to forming 
processes. The forming apparatus, including flow channels, is not 
considered part of the gas-fired glass-melting furnace. Cold-top 
electric glass-melting furnaces as defined in subpart NNN of this part 
are not gas-fired glass-melting furnaces.
    Glass pull rate means the mass of molten glass that is produced by 
a single glass-melting furnace or that is used in the manufacture of 
wool fiberglass at a single manufacturing line in a specified time 
period.
    Incinerator means an enclosed air pollution control device that 
uses controlled flame combustion to convert combustible materials to 
noncombustible gases. For the purposes of this subpart, the term 
``incinerator'' means ``regenerative thermal oxidizer''.
    Manufacturing line means the manufacturing equipment for the 
production of wool fiberglass that consists of a forming section where 
molten glass is fiberized and a fiberglass mat is formed and which may 
include a curing section where binder resin in the mat is thermally set 
and a cooling section where the mat is cooled.
    New source means any affected source the construction or 
reconstruction of which is commenced after April 15, 2013.
    Wool fiberglass means insulation materials composed of glass fibers 
made from glass produced or melted at the same facility where the 
manufacturing line is located.
    Wool fiberglass manufacturing facility means any facility 
manufacturing wool fiberglass.

Sec.  63.882  Emission standards.

    (a) Emission limits for gas-fired glass-melting furnaces. For each 
existing, new, or reconstructed gas-fired glass-melting furnace, on and 
after the compliance date specified in Sec.  63.887 whichever date is 
earlier, you must not discharge or cause to be discharged into the 
atmosphere emissions in excess of 0.00025 lb of chromium compounds per 
ton of glass pulled (0.25 lb per thousand tons glass pulled).
    (b) Operating limits. On and after the date on which the 
performance test required by Sec. Sec.  63.7 and 63.1384 is completed, 
you must operate all affected control equipment and processes according 
to the following requirements.
    (1)(i) You must initiate corrective action within one hour of an 
alarm from a bag leak detection system and complete corrective actions 
in a timely manner according to the procedures in the operations, 
maintenance, and monitoring plan.
    (ii) You must implement a Quality Improvement Plan consistent with 
the compliance assurance monitoring provisions of 40 CFR part 64, 
subpart D when the bag leak detection system alarm is sounded for more 
than 5 percent of the total operating time in a 6-month block reporting 
period.
    (2)(i) You must initiate corrective action within one hour when any 
3-hour block average of the monitored electrostatic precipitator (ESP) 
parameter is outside the limit(s) established during the performance 
test as specified in Sec.  63.884 and complete corrective actions in a 
timely manner according to the procedures in the operations, 
maintenance, and monitoring plan.
    (ii) You must implement a Quality Improvement Plan consistent with 
the compliance assurance monitoring provisions of 40 CFR part 64, 
subpart D when the monitored ESP parameter is outside the limit(s) 
established during the performance test as specified in Sec.  63.884 
for more than 5 percent of the total operating time in a 6-month block 
reporting period.
    (iii) You must operate the ESP such that the monitored ESP 
parameter is not outside the limit(s) established during the 
performance test as specified in Sec.  63.884 for more than 10 percent 
of the total operating time in a 6-month block reporting period.
    (3)(i) You must initiate corrective action within one hour when any 
3-hour block average value for the monitored parameter(s) for a gas-
fired glass-melting furnace, which uses no add-on controls, is outside 
the limit(s) established during the performance test as specified in 
Sec.  63.884 and complete corrective actions in a timely manner 
according to the procedures in the operations, maintenance, and 
monitoring plan.
    (ii) You must implement a Quality Improvement Plan consistent with 
the compliance assurance monitoring provisions of 40 CFR part 64, 
subpart D when the monitored parameter(s) is outside the limit(s) 
established during the performance test as specified in Sec.  63.884 
for more than 5 percent of the total operating time in a 6-month block 
reporting period.
    (iii) You must operate a gas-fired glass-melting furnace, which 
uses no add-on technology, such that the monitored parameter(s) is not 
outside the limit(s) established during the performance test as 
specified in Sec.  63.884 for more than 10 percent of the total 
operating time in a 6-month block reporting period.
    (4)(i) You must initiate corrective action within one hour when the 
average glass pull rate of any 4-hour block period for gas-fired glass-
melting furnaces equipped with continuous glass pull rate monitors, or 
daily glass pull rate for glass-melting furnaces not so equipped, 
exceeds the average glass pull rate established during the performance 
test as specified in Sec.  63.884, by greater than 20 percent and 
complete corrective actions in a timely manner according to the 
procedures in the operations, maintenance, and monitoring plan.
    (ii) You must implement a Quality Improvement Plan consistent with 
the compliance assurance monitoring provisions of 40 CFR part 64, 
subpart D when the glass pull rate exceeds, by more than 20 percent, 
the average glass pull rate established during the performance test as 
specified in Sec.  63.884 for more than 5 percent of the total 
operating time in a 6-month block reporting period.
    (iii) You must operate each gas-fired glass-melting furnace such 
that the glass pull rate does not exceed, by more than 20 percent, the 
average glass pull rate established during the most recent successful 
performance test as specified in Sec.  63.884 for more than 10 percent 
of the total operating time in a 6-month block reporting period.
    (5)(i) You must initiate corrective action within one hour when the 
average pH (for a caustic scrubber) or pressure drop (for a venturi 
scrubber) for any 3-hour block period is outside the limits established 
during the performance tests as specified in Sec.  63.884 for each wet 
scrubbing control

[[Page 45327]]

device and complete corrective actions in a timely manner according to 
the procedures in the operations, maintenance, and monitoring plan.
    (ii) You must implement a Quality Improvement Plan consistent with 
the compliance assurance monitoring provisions of 40 CFR part 64, 
subpart D when any scrubber parameter is outside the limit(s) 
established during the performance test as specified in Sec.  63.884 
for more than 5 percent of the total operating time in a 6-month block 
reporting period.
    (iii) You must operate each scrubber such that each monitored 
parameter is not outside the limit(s) established during the 
performance test as specified in Sec.  63.884 for more than 10 percent 
of the total operating time in a 6-month block reporting period.

Sec.  63.883  Monitoring requirements.

    You must meet all applicable monitoring requirements contained in 
subpart NNN of this part.

Sec.  63.884  Performance test requirements.

    (a) If you are subject to the provisions of this subpart you must 
conduct a performance test to demonstrate compliance with the 
applicable emission limits in Sec.  63.882. For existing sources, 
compliance is demonstrated when the emission rate of the pollutant is 
equal to or less than each of the applicable emission limits in Sec.  
63.882 by July 31, 2017. For new sources compliance is demonstrated 
when the emission rate of the pollutant is equal to or less than each 
of the applicable emission limits in Sec.  63.882 by January 25, 2016 
or 180 days after initial startup, whichever is later. You must conduct 
the performance test according to the procedures in subpart A of this 
part and in this section.
    (b) You must meet all applicable performance test requirements 
contained in subpart NNN of this part.

Sec.  63.885  Test methods and procedures.

    (a) You must use the following methods to determine compliance with 
the applicable emission limits:
    (1) Method 1 at 40 CFR part 60, appendix A-1 for the selection of 
the sampling port location and number of sampling ports;
    (2) Method 2 at 40 CFR part 60, appendix A-1 for volumetric flow 
rate;
    (3) Method 3 or 3A (40 CFR part 60, appendix A-2) for oxygen and 
carbon dioxide for diluent measurements needed to correct the 
concentration measurements to a standard basis;
    (4) Method 4 at 40 CFR part 60, appendix A-4 for moisture content 
of the stack gas;
    (5) Method 29 (40 CFR part 60, appendix A-8) for the concentration 
of chromium compounds. Each run must consist of a minimum sample volume 
of two dry standard cubic meters.
    (6) An alternative method, subject to approval by the 
Administrator.
    (b) Each performance test must consist of three runs. You must use 
the average of the three runs in the applicable equation for 
determining compliance.

Sec.  63.886  Notification, recordkeeping, and reporting requirements.

    You must meet all applicable notification, recordkeeping and 
reporting requirements contained in subpart NNN of this part.

Sec.  63.887  Compliance dates.

    (a) Compliance dates. The owner or operator subject to the 
provisions of this subpart must be in compliance with the requirements 
of this subpart by no later than:
    (1) Except as noted in paragraph (a)(3) of this section, the 
compliance date for an owner or operator of an existing source subject 
to the provisions in this subpart would be July 31, 2017.
    (2) Except as noted in paragraph (a)(3) of this section, the 
compliance date for new and reconstructed sources is upon initial 
startup of a new gas-fired glass-melting furnace or on July 29, 2015, 
whichever is later.
    (3) The compliance date for the provisions related to the 
electronic reporting provisions of Sec.  63.886 is on July 29, 2015.
    (b) Compliance extension. The owner or operator of an existing 
source subject to this subpart may request from the Administrator an 
extension of the compliance date for the emission standards for one 
additional year if such additional period is necessary for the 
installation of controls. You must submit a request for an extension 
according to the procedures in Sec.  63.6(i)(3).

Sec.  63.888  Startups and shutdowns.

    You must meet all applicable startup and shutdown provisions 
contained in subpart NNN of this part.

Sec. Sec.  63.889-63.899  [Reserved]

 Table 1 to Subpart NN of Part 63--Applicability of General Provisions (40 CFR Part 63, Subpart A) to Subpart NN
----------------------------------------------------------------------------------------------------------------
   General provisions  citation             Requirement         Applies to subpart NN         Explanation
----------------------------------------------------------------------------------------------------------------
Sec.   63.1(a)(1)-(5).............  Applicability.............  Yes
Sec.   63.1(a)(6).................  ..........................  Yes
Sec.   63.1(a)(7)-(9).............  ..........................  No...................  [Reserved].
Sec.   63.1(a)(10)-(12)...........  ..........................  Yes
Sec.   63.1(b)(1).................  Initial Applicability       Yes
                                     Determination.
Sec.   63.1(b)(2).................  ..........................  No...................  [Reserved].
Sec.   63.1(b)(3).................  ..........................  Yes
Sec.   63.1(c)(1)-(2).............  ..........................  Yes
Sec.   63.1(c)(3)-(4).............  ..........................  No...................  [Reserved].
Sec.   63.1(c)(5)-(e).............  ..........................  Yes
Sec.   63.2.......................  Definitions...............  Yes..................  Additional definitions in
                                                                                        Sec.   63.881.
Sec.   63.3.......................  Units and Abbreviations...  Yes
Sec.   63.4(a)(1)-(2).............  Prohibited Activities.....  Yes
Sec.   63.4(a)(3)-(5).............  ..........................  No...................  [Reserved].
Sec.   63.4(b)-(c)................  ..........................  Yes
Sec.   63.5(a)-(b)(2).............  Construction/               Yes
                                     Reconstruction
                                     Applicability.
Sec.   63.5(b)(3)-(4).............  ..........................  Yes
Sec.   63.5(b)(5).................  ..........................  No...................  [Reserved].
Sec.   63.5(b)(6).................  ..........................  Yes
Sec.   63.5(c)....................  ..........................  No...................  [Reserved].
Sec.   63.5(d)....................  Application for Approval    Yes
                                     of Construction/
                                     Reconstruction.

[[Page 45328]]

 
Sec.   63.5(e)....................  Approval of Construction/   Yes
                                     Reconstruction.
Sec.   63.5(f)....................  Approval of Construction/   Yes
                                     Reconstruction Based on
                                     State Review.
Sec.   63.6(a)-(d)................  Compliance with Standards   Yes
                                     and Maintenance
                                     Requirements.
Sec.   63.6(e)(1)(i)..............  General Duty to Minimize    No...................  See Sec.   63.882 for
                                     Emissions.                                         general duty
                                                                                        requirements.
Sec.   63.6(e)(1)(ii).............  Requirement to Correct      No
                                     Malfunctions As Soon As
                                     Possible.
Sec.   63.6(e)(1)(iii)............  ..........................  Yes
Sec.   63.6(e)(2).................  ..........................  No...................  [Reserved].
Sec.   63.6(e)(3).................  Startup, Shutdown, and      No...................  Startups and shutdowns
                                     Malfunction (SSM) Plan.                            addressed in Sec.
                                                                                        63.888.
Sec.   63.6(f)(1).................  SSM Exemption.............  No
Sec.   63.6(f)(2)-(3).............  Methods for Determining     Yes
                                     Compliance.
Sec.   63.6(g)....................  Use of an Alternative       Yes
                                     Nonopacity Emission.
Sec.   63.6(h)(1).................  SSM Exemption.............  No
Sec.   63.6(h)(2)-(j).............  ..........................  Yes
Sec.   63.7(a)-(d)................  ..........................  Yes..................  Sec.   63.884 has
                                                                                        specific requirements.
Sec.   63.7(e)(1).................  Performance Testing.......  No...................  See Sec.   63.882.
Sec.   63.7(e)(2)-(4).............  ..........................  Yes
Sec.   63.7(f)....................  Alternative Test Method...  Yes
Sec.   63.7(g)(1).................  Data Analysis.............  Yes
Sec.   63.7(g)(2).................  ..........................  No...................  [Reserved].
Sec.   63.7(g)(3).................  ..........................  Yes
Sec.   63.7(h)....................  Waiver of Performance Test  Yes
Sec.   63.8(a)-(b)................  Monitoring Requirements...  Yes
Sec.   63.8(c)(1)(i)..............  General Duty to Minimize    No...................  See Sec.   63.882(b) for
                                     Emissions and CMS                                  general duty
                                     Operation.                                         requirement.
Sec.   63.8(c)(1)(ii).............  ..........................  Yes
Sec.   63.8(c)(1)(iii)............  Requirement to Develop SSM  No
                                     Plan for CMS.
Sec.   63.8(c)(2)-(d)(2)..........  ..........................  Yes
Sec.   63.8(d)(3).................  Written Procedures for CMS  Yes, except for last
                                                                 sentence, which
                                                                 refers to SSM plan.
                                                                 SSM plans are not
                                                                 required
Sec.   63.8(e)-(g)................  ..........................  Yes
Sec.   63.9(a)....................  Notification Requirements.  Yes
Sec.   63.9(b)(1)-(2).............  Initial Notifications.....  Yes
Sec.   63.9(b)(3).................  ..........................  No...................  [Reserved].
Sec.   63.9(b)(4)-(5).............  ..........................  Yes
Sec.   63.9(c)-(j)................  ..........................  Yes
Sec.   63.10(a)...................  Recordkeeping and           Yes
                                     Reporting-Requirements.
Sec.   63.10(b)(1)................  General Recordkeeping       Yes
                                     Requirements.
Sec.   63.10(b)(2)(i).............  Recordkeeping of            No
                                     Occurrence and Duration
                                     of Startups and Shutdowns.
Sec.   63.10(b)(2)(ii)............  Recordkeeping of            No...................  See Sec.   63.886 for
                                     Malfunctions.                                      recordkeeping of
                                                                                        occurrence and duration
                                                                                        of malfunctions and
                                                                                        recordkeeping of actions
                                                                                        taken during
                                                                                        malfunction.
Sec.   63.10(b)(2)(iii)...........  Maintenance Records.......  Yes
Sec.   63.10(b)(2)(iv)-(v)........  Actions Taken to Minimize   No
                                     Emissions During SSM.
Sec.   63.10(b)(2)(vi)............  Recordkeeping for CMS       Yes
                                     Malfunctions.
Sec.   63.10(b)(2)(vii)-(xiv).....  Other CMS Requirements....  Yes
Sec.   63.10(b)(3)................  Recordkeeping Requirement   Yes
                                     for Applicability
                                     Determinations.
Sec.   63.10(c)(1)-(6)............  Additional Recordkeeping    Yes
                                     Requirements for Sources
                                     with CMS.
Sec.   63.10(c)(7)-(8)............  Additional Recordkeeping    Yes
                                     Requirements for CMS--
                                     Identifying Exceedances
                                     and Excess Emissions.
Sec.   63.10(c)(9)................  ..........................  No...................  [Reserved].
Sec.   63.10(c)(10)-(11)..........  ..........................  No...................  See Sec.   63.886 for
                                                                                        recordkeeping of
                                                                                        malfunctions.
Sec.   63.10(c)(12)-(14)..........  ..........................  Yes
Sec.   63.10(c)(15)...............  Use of SSM Plan...........  No
Sec.   63.10(d)(1)-(4)............  General Reporting           Yes
                                     Requirements.
Sec.   63.10(d)(5)................  SSM Reports...............  No...................  See Sec.   63.886(c)(2)
                                                                                        for reporting of
                                                                                        malfunctions.

[[Page 45329]]

 
Sec.   63.10(e)-(f)...............  Additional CMS Reports      Yes
                                     Excess Emission/CMS
                                     Performance Reports COMS
                                     Data Reports
                                     Recordkeeping/Reporting
                                     Waiver.
Sec.   63.11(a)-(b)...............  Control Device              No...................  Flares will not be used
                                     Requirements                                       to comply with the
                                     Applicability Flares.                              emissions limits.
Sec.   63.11(c)...................  Alternative Work Practice   Yes
                                     for Monitoring Equipment
                                     for Leaks.
Sec.   63.11(d)...................  Alternative Work Practice   Yes
                                     Standard.
Sec.   63.11(e)...................  Alternative Work Practice   Yes
                                     Requirements.
Sec.   63.12......................  State Authority and         Yes
                                     Delegations.
Sec.   63.13......................  Addresses.................  Yes
Sec.   63.14......................  Incorporation by Reference  Yes
Sec.   63.15......................  Information Availability/   Yes
                                     Confidentiality.
Sec.   63.16......................  Performance Track           Yes
                                     Provisions.
----------------------------------------------------------------------------------------------------------------

Subpart DDD--National Emission Standards for Hazardous Air 
Pollutants for Mineral Wool Production

0
3. Section 63.1178 is amended by revising paragraphs (a) and (b)(3) to 
read as follows:

Sec.  63.1178  For cupolas, what standards must I meet?

    (a) You must control emissions from each cupola as specified in 
Table 2 to this subpart.
    (b) * * *
    (3) Additionally, on or after the applicable compliance date for 
each new or reconstructed cupola, you must either:
    (i) Maintain the operating temperature of the incinerator so that 
the average operating temperature for each three-hour block period 
never falls below the average temperature established during the 
performance test, or
    (ii) Maintain the percent excess oxygen in the cupola at or above 
the level established during the performance test. You must determine 
the percent excess oxygen using the following equation:
[GRAPHIC] [TIFF OMITTED] TR29JY15.000

Where:

Percent excess oxygen = Percentage of excess oxygen present above 
the stoichiometric balance of 1.00, (%).
1.00 = Ratio of oxygen in a cupola combustion chamber divided by the 
stoichiometric quantity of oxygen required to obtain complete 
combustion of fuel.
Oxygen available = Quantity of oxygen introduced into the cupola 
combustion zone.
Fuel demand for oxygen = Required quantity of oxygen for 
stoichiometric combustion of the quantity of fuel present.

0
4. Section 63.1179 is amended by revising the section heading, 
paragraph (a), and paragraph (b) introductory text to read as follows:

Sec.  63.1179  For curing ovens or combined collection/curing 
operations, what standards must I meet?

    (a) You must control emissions from each curing oven or combined 
collection/curing operations as specified in Table 2 to this subpart.
    (b) You must meet the following operating limits for each curing 
oven or combined collection/curing operation:
* * * * *

0
5. Section 63.1180 is revised to read as follows:

Sec.  63.1180  When must I meet these standards?

    (a) Cupolas and curing ovens or combined collection/curing 
operations. You must comply with the emissions limits specified in 
Table 2 to this subpart no later than the dates specified in Table 2 to 
this subpart.
    (b) At all times, you must operate and maintain any affected 
source, including associated air pollution control equipment and 
monitoring equipment, in a manner consistent with safety and good air 
pollution control practices for minimizing emissions. Determination of 
whether such operation and maintenance procedures are being used will 
be based on information available to the Administrator which may 
include, but is not limited to, monitoring results, review of operation 
and maintenance procedures, review of operation and maintenance 
records, and inspection of the source.

0
6. Section 63.1182 is amended by revising the section heading, the 
introductory text, and paragraphs (a) and (b) to read as follows:

Sec.  63.1182  How do I comply with the carbon monoxide, carbonyl 
sulfide, hydrogen fluoride, and hydrogen chloride standards for 
existing, new, and reconstructed cupolas?

    To comply with the carbon monoxide, carbonyl sulfide, hydrogen 
fluoride, and hydrogen chloride standards, you must meet the following:
    (a) Install, calibrate, maintain, and operate a device that 
continuously measures the operating temperature in the firebox of each 
thermal incinerator.
    (b) Conduct a performance test as specified in Sec.  63.1188 that 
shows compliance with the carbon monoxide, carbonyl sulfide, hydrogen 
fluoride, and hydrogen chloride emissions limits specified in Table 2 
to this subpart, while the device for measuring incinerator operating 
temperature is installed, operational, and properly calibrated. 
Establish the average operating temperature based on the performance 
test as specified in Sec.  63.1185(a).
* * * * *

[[Page 45330]]

0
7. Section 63.1183 is amended by revising the section heading, the 
introductory text, and paragraphs (b) and (d) to read as follows:

Sec.  63.1183  How do I comply with the formaldehyde, phenol, and 
methanol standards for existing, new, and reconstructed combined 
collection/curing operations?

    To comply with the formaldehyde, phenol, and methanol standards, 
you must meet all of the following:
* * * * *
    (b) Conduct a performance test as specified in Sec.  63.1188 while 
manufacturing the product that requires a binder formulation made with 
the resin containing the highest free-formaldehyde content 
specification range. Show compliance with the formaldehyde, phenol, and 
methanol emissions limits, specified in Table 2 to this subpart, while 
the device for measuring the control device operating parameter is 
installed, operational, and properly calibrated. Establish the average 
operating parameter based on the performance test as specified in Sec.  
63.1185(a).
* * * * *
    (d) Following the performance test, monitor and record the free-
formaldehyde content of each resin lot and the formulation of each 
batch of binder used, including the formaldehyde, phenol, and methanol 
content.
* * * * *

0
8. Section 63.1188 is amended by revising paragraphs (b), (c), (d), 
(e), and (f) to read as follows:

Sec.  63.1188  What performance test requirements must I meet?

* * * * *
    (b) Conduct a performance test, consisting of three test runs, for 
each cupola and curing oven or combined collection/curing operation 
subject to this subpart at the maximum production rate to demonstrate 
compliance with each of the applicable emissions limits specified in 
Table 2 to this subpart.
    (c) Following the initial performance or compliance test to be 
conducted within 180 days of the effective date of this rule, you must 
conduct a performance test to demonstrate compliance with each of the 
applicable emissions limits specified in Table 2 to this subpart, at 
least once every 5 years.
    (d) To demonstrate compliance with the applicable emission limits 
specified in Table 2 to this subpart, measure emissions of PM, carbon 
monoxide, carbonyl sulfide, hydrogen fluoride, and hydrogen chloride 
from each existing, new, or reconstructed cupola.
    (e) To demonstrate compliance with the applicable emission limits 
specified in Table 2 to this subpart, measure emissions of 
formaldehyde, phenol, and methanol from each existing, new, or 
reconstructed curing oven or combined collection/curing operation.
    (f) To demonstrate compliance with the applicable emission limits 
specified in Table 2 to this subpart, measure emissions at the outlet 
of the control device for PM, carbon monoxide, carbonyl sulfide, 
hydrogen fluoride, hydrogen chloride, formaldehyde, phenol, and 
methanol.
* * * * *

0
9. Section 63.1189 is amended by revising paragraph (g) and adding 
paragraph (i) to read as follows:

Sec.  63.1189  What test methods do I use?

* * * * *
    (g) Method 318 at 40 CFR part 60, appendix A to this part for the 
concentration of formaldehyde, phenol, methanol, and carbonyl sulfide.
* * * * *
    (i) Method 26A or 320 at 40 CFR part 60, appendix A to this part 
for the concentration of hydrogen fluoride and hydrogen chloride.

0
10. Section 63.1190 is amended by revising paragraph (b) introductory 
text and the definition of ``MW,'' and by removing paragraph (c) to 
read as follows:

Sec.  63.1190  How do I determine compliance?

* * * * *
    (b) Using the results from the performance tests, you must use the 
following equation to determine compliance with the carbon monoxide, 
carbonyl sulfide, hydrogen fluoride, hydrogen chloride, formaldehyde, 
phenol, and methanol numerical emissions limits as specified in Table 2 
to this subpart:
* * * * *

MW = Molecular weight of measured pollutant, g/g-mole: Carbon 
monoxide = 28.01, carbonyl sulfide = 60.07, hydrogen fluoride = 
20.01, hydrogen chloride = 36.46, Formaldehyde = 30.03, Phenol = 
94.11, Methanol = 32.04.

* * * * *

0
11. Section 63.1191 is amended by revising the introductory text to 
read as follows:

Sec.  63.1191  What notifications must I submit?

    You must submit written or electronic notifications to the 
Administrator as required by Sec.  63.9(b) through (h). Electronic 
notifications are encouraged when possible. These notifications 
include, but are not limited to, the following:
* * * * *

0
12. Section 63.1192 is amended by revising paragraph (d) to read as 
follows:

Sec.  63.1192  What recordkeeping requirements must I meet?

* * * * *
    (d) Records must be maintained in a form suitable and readily 
available for expeditious review, according to Sec.  63.10 of the 
General Provisions that are referenced in Table 1 to this subpart. 
Electronic recordkeeping is encouraged.
* * * * *

0
13. Section 63.1193 is amended by revising paragraph (a), removing and 
reserving paragraph (b), and adding a new paragraph (g) to read as 
follows:

Sec.  63.1193  What reports must I submit?

* * * * *
    (a) Within 60 days after the date of completing each performance 
test (as defined in Sec.  63.2) required by this subpart, you must 
submit the results of the performance tests, including any associated 
fuel analyses, following the procedure specified in either paragraph 
(a)(1) or (2) of this section.
    (1) For data collected using test methods supported by the EPA's 
Electronic Reporting Tool (ERT) as listed on the EPA's ERT Web site 
(http://www.epa.gov/ttn/chief/ert/index.html), you must submit the 
results of the performance test to the EPA via the Compliance and 
Emissions Data Reporting Interface (CEDRI). CEDRI can be accessed 
through the EPA's Central Data Exchange (CDX) (http://cdx.epa.gov/epa_home.asp). Performance test data must be submitted in a file format 
generated through the use of the EPA's ERT. Alternatively, you may 
submit performance test data in an electronic file format consistent 
with the extensible markup language (XML) schema listed on the EPA's 
ERT Web site, once the XML schema is available. If you claim that some 
of the performance test information being submitted is confidential 
business information (CBI), you must submit a complete file generated 
through the use of the EPA's ERT or an alternate electronic file 
consistent with the XML schema listed on the EPA's ERT Web site, 
including information claimed to be CBI, on a compact disc, flash 
drive, or other commonly used electronic storage media to the EPA. The 
electronic media must be clearly marked as CBI and mailed to U.S. EPA/
OAPQS/CORE CBI Office, Attention: Group Leader, Measurement Policy 
Group, MD C404-

[[Page 45331]]

02, 4930 Old Page Rd., Durham, NC 27703. The same ERT or alternate file 
with the CBI omitted must be submitted to the EPA via the EPA's CDX as 
described earlier in this paragraph.
    (2) For data collected using test methods that are not supported by 
the EPA's ERT as listed on the EPA's ERT Web site, you must submit the 
results of the performance test to the Administrator at the appropriate 
address listed in Sec.  63.13.
    (b) [Reserved]
* * * * *
    (g) All reports required by this subpart not subject to the 
requirements in paragraph (a) of this section must be sent to the 
Administrator at the appropriate address listed in Sec.  63.13. If 
acceptable to both the Administrator and the owner or operator of a 
source, these reports may be submitted on electronic media. The 
Administrator retains the right to require submittal of reports subject 
to paragraph (a) of this section in paper format.

0
14. Section 63.1196 is amended by:
0
a. Adding in alphabetical order definitions for ``Closed-top cupola'', 
``Combined collection/curing operations'', ``Open-top cupola'', and 
``Slag''; and
0
b. Revising the definition of ``Incinerator'' and ``New Source''.
    The additions and revision read as follows:

Sec.  63.1196  What definitions should I be aware of?

* * * * *
    Closed-top cupola means a cupola that operates as a closed 
(process) system and has a restricted air flow rate.
* * * * *
    Combined collection/curing operations means the combination of 
fiber collection operations and curing ovens used to make bonded 
products.
* * * * *
    Incinerator means an enclosed air pollution control device that 
uses controlled flame combustion to convert combustible materials to 
noncombustible gases. For the purposes of this subpart, the term 
``incinerator'' means ``regenerative thermal oxidizer''.
* * * * *
    New Source means any affected source that commences construction or 
reconstruction after May 8, 1997 for purposes of determining the 
applicability of the emissions limits in Rows 1-4 of Table 2. For all 
other emission limits new source means any affected source that 
commences construction or reconstruction after November 25, 2011.
* * * * *
    Open-top cupola means a cupola that is open to the outside air and 
operates with an air flow rate that is unrestricted and at low 
pressure.
* * * * *
    Slag means the by-product materials separated from metals during 
smelting and refining of raw ore.
* * * * *

0
15. Section 63.1197 is added to read as follows:

Sec.  63.1197  Startups and shutdowns.

    (a) The provisions set forth in this subpart apply at all times.
    (b) You must not shut down items of equipment that are utilized for 
compliance with this subpart during times when emissions are being, or 
are otherwise required to be, routed to such items of equipment.
    (c) Startup begins when fuels are ignited in the cupola. Startup 
ends when the cupola produces molten material.
    (d) Shutdown begins when the cupola has reached the end of the 
melting campaign and is empty. No molten material continues to flow 
from the cupola during shutdown.
    (e) During periods of startups and shutdowns you must operate your 
cupola according to one of the following methods:
    (1) You must keep records showing that your emissions were 
controlled using air pollution control devices operated at the 
parameters established by the most recent performance test that showed 
compliance with the standard; or
    (2) You must keep records showing the following:
    (i) You used only clean fuels during startup and shutdown; and
    (ii) You operate the cupola during startup and shutdown with three 
percent oxygen over the fuel demand for oxygen.

0
16. Table 1 to subpart DDD of part 63 is revised to read as follows:

  Table 1 to Subpart DDD of Part 63--Applicability of General Provisions (40 CFR Part 63, Subpart A) to Subpart
                                                       DDD
----------------------------------------------------------------------------------------------------------------
                                                                  Applies to subpart
   General provisions  citation             Requirement                  DDD?                 Explanation
----------------------------------------------------------------------------------------------------------------
Sec.   63.1(a)(1)-(6).............  General Applicability.....  Yes..................
Sec.   63.1(a)(7)-(9).............  ..........................  No...................  [Reserved].
Sec.   63.1(a)(10)-(12)...........  ..........................  Yes..................
Sec.   63.1(b)(1).................  Initial Applicability       Yes..................
                                     Determination.
Sec.   63.1(b)(2).................  ..........................  No...................  [Reserved].
Sec.   63.1(b)(3).................  ..........................  Yes..................
Sec.   63.1(c)(1)-(2).............  Applicability After         Yes..................
                                     Standard Established.
Sec.   63.1(c)(3)-(4).............  ..........................  No...................  [Reserved].
Sec.   63.1(c)(5)-(e).............  ..........................  Yes..................
Sec.   63.2.......................  Definitions...............  Yes..................
Sec.   63.3.......................  Units and Abbreviations...  Yes..................
Sec.   63.4(a)(1)-(2).............  Prohibited Activities.....  Yes..................
Sec.   63.4(a)(3)-(5).............  ..........................  No...................  [Reserved].
Sec.   63.4(b)-(c)................  ..........................  Yes..................
Sec.   63.5(a)(1)-(b)(2)..........  Construction/               Yes..................
                                     Reconstruction
                                     Applicability.
Sec.   63.5(b)(3)-(4).............  ..........................  Yes..................
Sec.   63.5(b)(5).................  ..........................  No...................  [Reserved].
Sec.   63.5(b)(6).................  ..........................  Yes..................
Sec.   63.5(c)....................  ..........................  No...................  [Reserved].
Sec.   63.5(d)-(f)................  ..........................  Yes..................
Sec.   63.6(a)-(d)................  ..........................  Yes..................
Sec.   63.6(e)(1)(i)..............  General Duty to Minimize    No...................  See Sec.   63.1180(d) for
                                     Emissions.                                         general duty
                                                                                        requirement.

[[Page 45332]]

 
Sec.   63.6(e)(1)(ii).............  Requirement to Correct      No...................  Sec.   63.1187(b)
                                     Malfunctions As Soon As                            specifies additional
                                     Possible.                                          requirements.
Sec.   63.6(e)(1)(iii)............  ..........................  Yes..................
Sec.   63.6(e)(2).................  ..........................  No...................  [Reserved].
Sec.   63.6(e)(3).................  Startup, Shutdown,          No...................  Startups and shutdowns
                                     Malfunction (SSM) Plan.                            addressed in Sec.
                                                                                        63.1197.
Sec.   63.6(f)(1).................  SSM Exemption.............  No...................
Sec.   63.6(f)(2)-(g).............  ..........................  Yes..................
Sec.   63.6(h)(1).................  SSM Exemption.............  No...................
Sec.   63.6(h)(2)-(j).............  ..........................  Yes..................
Sec.   63.7(a)-(d)................  Performance Testing         Yes..................
                                     Requirements.
Sec.   63.7(e)(1).................  Conduct of Performance      No...................  See Sec.   63.1180.
                                     Tests.
Sec.   63.7(e)(2)-(f).............  ..........................  Yes..................
Sec.   63.7(g)(1).................  Data Analysis,              Yes..................
                                     Recordkeeping, and
                                     Reporting.
Sec.   63.7(g)(2).................  ..........................  No...................  [Reserved].
Sec.   63.7(g)(3)-(h).............  ..........................  Yes..................
Sec.   63.8(a)-(b)................  Monitoring Requirements...  Yes..................
Sec.   63.8(c)(1)(i)..............  General Duty to Minimize    No...................  See Sec.   63.1180(e) for
                                     Emissions and CMS                                  general duty
                                     Operation.                                         requirement.
Sec.   63.8(c)(1)(ii).............  ..........................  Yes..................
Sec.   63.8(c)(1)(iii)............  Requirement to Develop SSM  No...................
                                     Plan for CMS.
Sec.   63.8(c)(2)-(d)(2)..........  ..........................  Yes..................
Sec.   63.8(d)(3).................  Written Procedures for CMS  Yes, except for last   .........................
                                                                 sentence, which
                                                                 refers to SSM plan.
                                                                 SSM plans are not
                                                                 required..
Sec.   63.8(e)-(g)................  ..........................  Yes..................
Sec.   63.9(a)....................  Applicability and General   Yes..................
                                     Information.
Sec.   63.9(b)(1)-(2).............  Initial Notifications.....  Yes..................
Sec.   63.9(b)(3).................  ..........................  No...................  [Reserved].
Sec.   63.9(b)(4)-(b)(5)..........  ..........................  Yes..................
Sec.   63.9(c)-(j)................  ..........................  Yes..................
Sec.   63.10(a)...................  Recordkeeping and           Yes..................
                                     Reporting Requirements.
Sec.   63.10(b)(1)................  General Recordkeeping       Yes..................
                                     Requirements.
Sec.   63.10(b)(2)(i).............  Recordkeeping of            No...................
                                     Occurrence and Duration
                                     of Startups and Shutdowns.
Sec.   63.10(b)(2)(ii)............  Recordkeeping of            No...................  See Sec.   63.1193(c) for
                                     Malfunctions.                                      recordkeeping of (ii)
                                                                                        occurrence and duration
                                                                                        and (iii) actions taken
                                                                                        during malfunction.
Sec.   63.10(b)(2)(iii)...........  Maintenance Records.......  Yes..................
Sec.   63.10(b)(2)(iv)-(v)........  Actions Taken to Minimize   No...................
                                     Emissions During SSM.
Sec.   63.10(b)(2)(vi)............  Recordkeeping for CMS       Yes..................
                                     Malfunctions.
Sec.   63.10(b)(2)(vii)-(xiv).....  Other CMS Requirements....  Yes..................
Sec.   63.10(b)(3)................  Recordkeeping Requirement   Yes..................
                                     for Applicability
                                     Determinations.
Sec.   63.10(c)(1)-(6)............  Additional Recordkeeping    Yes..................
                                     Requirements for Sources
                                     with CMS.
Sec.   63.10(c)(7)-(8)............  Additional Recordkeeping    Yes..................
                                     Requirements for CMS--
                                     Identifying Exceedances
                                     and Excess Emissions.
Sec.   63.10(c)(9)................  ..........................  No...................  [Reserved].
Sec.   63.10(c)(10)-(11)..........  ..........................  No...................  See Sec.   63.1192 for
                                                                                        recordkeeping of
                                                                                        malfunctions.
Sec.   63.10(c)(12)-(14)..........  ..........................  Yes..................
Sec.   63.10(c)(15)...............  Use of SSM Plan...........  No...................
Sec.   63.10(d)(1)-(4)............  General Reporting           Yes..................
                                     Requirements.
Sec.   63.10(d)(5)................  SSM Reports...............  No...................  See Sec.   63.1193(f) for
                                                                                        reporting of
                                                                                        malfunctions.
Sec.   63.10(e)-(f)...............  Additional CMS Reports      Yes..................
                                     Excess Emission/CMS
                                     Performance Reports COMS
                                     Data Reports
                                     Recordkeeping/Reporting
                                     Waiver.
Sec.   63.11(a)-(b)...............  Control Device              No...................  Flares will not be used
                                     Requirements                                       to comply with the
                                     Applicability Flares.                              emissions limits.
Sec.   63.11(c)...................  Alternative Work Practice   Yes..................
                                     for Monitoring Equipment
                                     for Leaks.
Sec.   63.11(d)...................  Alternative Work Practice   Yes..................
                                     Standard.
Sec.   63.11(e)...................  ..........................  Yes..................
Sec.   63.12......................  State Authority and         Yes..................
                                     Delegations.
Sec.   63.13......................  Addresses.................  Yes..................

[[Page 45333]]

 
Sec.   63.14......................  Incorporation by Reference  Yes..................
Sec.   63.15......................  Information Availability/   Yes..................
                                     Confidentiality.
Sec.   63.16......................  Performance Track           Yes..................
                                     Provisions.
----------------------------------------------------------------------------------------------------------------

0
17. Subpart DDD is amended by adding Table 2 to read as follows:

                    Table 2 to Subpart DDD of Part 63--Emissions Limits and Compliance Dates
----------------------------------------------------------------------------------------------------------------
                                      And you commenced    Your emission limits
       If your source is a:             construction:            are: \1\          And you must comply by: \2\
----------------------------------------------------------------------------------------------------------------
1. Cupola.........................  On or before May 8,    0.10 lb PM per ton    June 2, 2002.
                                     1997.                  of melt.
2. Cupola.........................  After May 8, 1997....  0.10 lb PM per ton    June 1, 1999.
                                                            of melt.
3. Cupola.........................  On or before May 8,    a. 0.10 lb carbon     June 2, 2002.
                                     1997.                  monoxide (CO) per
                                                            ton of melt,\3\ or
                                                           b. Reduction of
                                                            uncontrolled CO by
                                                            at least 99 percent
                                                            \3\.
4. Cupola.........................  After May 8, 1997 but  a. 0.10 lb CO per     June 1, 1999.
                                     on or before           ton of melt,\3\ or
                                     November 25, 2011.    b. Reduction of
                                                            uncontrolled CO by
                                                            at least 99
                                                            percent.\3\.
5. Closed-top cupola..............  On or before November  3.4 lb of carbonyl    July 30, 2018.
                                     25, 2011.              sulfide (COS) per
                                                            ton melt.
6. Closed-top cupola..............  After November 25,     0.062 lb of COS per   July 29, 2015.\4\
                                     2011.                  ton melt.
7. Open-top cupola................  On or before November  6.8 lb of COS per     July 30, 2018.
                                     25, 2011.              ton melt.
8. Open-top cupola................  After November 25,     3.2 lb of COS per     July 29, 2015.\4\
                                     2011.                  ton melt.
9. Cupola using slag as a raw       On or before November  0.16 lb of hydrogen   July 30, 2018.
 material.                           25, 2011.              fluoride (HF) per
                                                            ton melt.
                                                           0.44 lb of hydrogen
                                                            chloride (HCl) per
                                                            ton melt..
10. Cupola using slag as a raw      After November 25,     0.015 lb of HF per    July 29, 2015.\4\
 material.                           2011.                  ton melt.
                                                           0.012 lb of HCl per
                                                            ton melt..
11. Cupola not using slag as a raw  On or before November  0.13 lb of HF per     July 30, 2018.
 material.                           25, 2011.              ton melt.
                                                           0.43 lb of HCl per
                                                            ton melt..
12. Cupola not using slag as a raw  After November 25,     0.018 lb of HF per    July 29, 2015.\4\
 material.                           2011.                  ton melt.
                                                           0.015 lb of HCl per
                                                            ton melt..
17. Curing oven...................  On or before May 8,    a. 0.06 lb of         June 2, 2002.
                                     1997.                  formaldehyde per
                                                            ton of melt,\3\ or
                                                           b. Reduction of
                                                            uncontrolled
                                                            formaldehyde by at
                                                            least 80
                                                            percent.\3\.
18. Curing oven...................  After May 8, 1997 but  a. 0.06 lb of         June 1, 1999.
                                     before November 25,    formaldehyde per
                                     2011.                  ton of melt,\3\ or
                                                           b. Reduction of
                                                            uncontrolled
                                                            formaldehyde by at
                                                            least 80
                                                            percent.\3\.
19. Combined drum collection/       On or before November  0.17 lb of            July 30, 2018.
 curing operation.                   25, 2011.              formaldehyde per
                                                            ton of melt.
                                                           0.28 lb of methanol
                                                            per ton melt..
                                                           0.85 lb of phenol
                                                            per ton melt..
20. Combined drum collection/       After November 25,     0.17 lb of            July 29, 2015.\4\
 curing operation.                   2011.                  formaldehyde per
                                                            ton of melt.
                                                           0.28 lb of methanol
                                                            per ton melt..
                                                           0.85 lb of phenol
                                                            per ton melt..
21. Combined horizontal collection/ On or before November  0.63 lb of            July 30, 2018.
 curing operation.                   25, 2011.              formaldehyde per
                                                            ton of melt.
                                                           0.049 lb of methanol
                                                            per ton melt..
                                                           0.12 lb of phenol
                                                            per ton melt..
22. Combined horizontal collection/ After November 25,     0.63 lb of            July 29, 2015.\4\
 curing operation.                   2011.                  formaldehyde per
                                                            ton of melt.
                                                           0.049 lb of methanol
                                                            per ton melt..
                                                           0.12 lb of phenol
                                                            per ton melt..
23. Combined vertical collection/   On or before November  2.4 lb of             July 30, 2018.
 curing operation.                   25, 2011.              formaldehyde per
                                                            ton melt.
                                                           0.92 lb of methanol
                                                            per ton melt..
                                                           0.71 lb of phenol
                                                            per ton melt..
24. Combined vertical collection/   After November 25,     2.4 lb of             July 29, 2015.\4\
 curing operation.                   2011.                  formaldehyde per
                                                            ton melt.
                                                           0.92 lb of methanol
                                                            per ton melt..
                                                           0.71 lb of phenol
                                                            per ton melt..
----------------------------------------------------------------------------------------------------------------
\1\ The numeric emissions limits do not apply during startup and shutdown.
\2\ Existing sources must demonstrate compliance by the compliance dates specified in this table. New sources
  have 180 days after the applicable compliance date to demonstrate compliance.
\3\ This emissions limit does not apply after July 30, 2018.
\4\ Or upon initial startup, whichever is later.

[[Page 45334]]

Subpart NNN--National Emission Standards for Hazardous Air 
Pollutants for Wool Fiberglass Manufacturing

0
18. Section 63.1380 is amended by revising paragraph (b)(3) to read as 
follows:

Sec.  63.1380  Applicability.

* * * * *
    (b) * * *
    (3) Each new and existing flame attenuation wool fiberglass 
manufacturing line producing a bonded product.
* * * * *

0
19. Section 63.1381 is amended by:
0
a. Adding in alphabetical order a definition for ``Gas-fired glass-
melting furnace''; and
0
b. Revising the definitions of ``Incinerator'' and ``New source''.
    The addition and revisions read as follows:

Sec.  63.1381  Definitions.

* * * * *
    Gas-fired glass-melting furnace means a unit comprising a 
refractory vessel in which raw materials are charged, melted at high 
temperature using natural gas and other fuels, refined, and conditioned 
to produce molten glass. The unit includes foundations, superstructure 
and retaining walls, raw material charger systems, heat exchangers, 
exhaust system, refractory brick work, fuel supply and electrical 
boosting equipment, integral control systems and instrumentation, and 
appendages for conditioning and distributing molten glass to forming 
processes. The forming apparatus, including flow channels, is not 
considered part of the gas-fired glass-melting furnace. Cold-top 
electric furnaces as defined in this subpart are not gas-fired glass-
melting furnaces.
* * * * *
    Incinerator means an enclosed air pollution control device that 
uses controlled flame combustion to convert combustible materials to 
noncombustible gases. For the purposes of this subpart, the term 
``incinerator'' means ``regenerative thermal oxidizer''.
* * * * *
    New source means any affected source that commences construction or 
reconstruction after March 31, 1997 for purposes of determining the 
applicability of the emission limits in rows 1, 2 and 7 through 11 in 
Table 2. New source means any affected source that commences 
construction or reconstruction after November 25, 2011 for purposes of 
determining the applicability of all other emissions limits.
* * * * *

0
20. Section 63.1382 is amended by revising paragraph (a), redesignating 
paragraph (b) as paragraph (c), and adding new pargraph (b) and 
paragraph (c)(11) to read as follows:

Sec.  63.1382  Emission standards.

    (a) You must control emissions from each glass-melting furnace, 
rotary spin manufacturing line, and flame attenuation manufacturing 
line as specified in Table 2 to this subpart.
    (b) On or after July 29, 2015 to reduce emissions of hydrogen 
chloride and hydrogen fluoride from each existing, new, or 
reconstructed glass-melting furnace, you must either:
    (1) Require cullet providers to provide records of their 
inspections showing that no glass from industrial (also known as 
continuous strand, or textile) fiberglass, cathode ray tubes (CRT), 
computer monitors that include CRT, and glass from microwave ovens, 
televisions or other electronics is included in the cullet; or
    (2) Sample your raw materials and maintain records of your sampling 
showing that the cullet is free of glass from industrial fiberglass, 
cathode ray tubes, computer monitors that include cathode ray tubes, 
and glass from microwave ovens, televisions or other electronics.
    (c) * * *
    (11) The owner or operator must maintain the percentage of cullet 
in the materials mix for each gas-fired glass-melting furnace at or 
below the level established during the performance test as specified in 
Sec.  63.1384(a)(4).

0
21. Section 63.1383 is amended by revising paragraphs (f) and (m) to 
read as follows:

Sec.  63.1383  Monitoring requirements.

* * * * *
    (f) If you use a control device to control HAP emissions from a 
glass-melting furnace, RS manufacturing line, or FA manufacturing line, 
you must install, calibrate, maintain, and operate a monitoring device 
that continuously measures an appropriate parameter for the control 
device. You must establish the value of that parameter during the 
performance test conducted to demonstrate compliance with the 
applicable emission limit as specified in Table 2 to this subpart.
* * * * *
    (m) For all control device and process operating parameters 
measured during the initial performance tests, including the materials 
mix used in the test, you may change the limits established during the 
initial performance tests if you conduct additional performance testing 
to verify that, at the new control device or process parameter levels, 
you comply with the applicable emission limits specified in Table 2 to 
this subpart. You must conduct all additional performance tests 
according to the procedures in this part 63, subpart A and in Sec.  
63.1384.

0
22. Section 63.1384 is amended by revising paragraphs (a)(4) and (c) 
introductory text, and the definitions of ``E'', ``C'', and ``MW'', and 
adding paragraphs (d) and (e) to read as follows:

Sec.  63.1384  Performance test requirements.

    (a) * * *
    (4) The owner or operator shall conduct a performance test for each 
existing and new gas-fired glass-melting furnace. During the 
performance test of each gas-fired glass-melting furnace, the owner or 
operator must measure and record the materials mix, including the 
percentages of raw materials and cullet, melted in the furnace during 
the performance test.
* * * * *
    (c) To determine compliance with the emission limits specified in 
Table 2 to this subpart, for formaldehyde for RS manufacturing lines; 
formaldehyde, phenol, and methanol for FA manufacturing lines; and 
chromium compounds for gas-fired glass-melting furnaces, use the 
following equation:
* * * * *
E = Emission rate of formaldehyde, phenol, methanol, chromium 
compounds, kg/Mg (lb/ton) of glass pulled;
C = Measured volume fraction of formaldehyde, phenol, methanol, 
chromium compounds, ppm;
MW = Molecular weight of formaldehyde, 30.03 g/g-mol; molecular 
weight of phenol, 94.11 g/g-mol; molecular weight of methanol, 32.04 
g/g-mol; molecular weight of chromium compounds tested in g/g-mol.
* * * * *
    (d) Following the initial performance or compliance test conducted 
to demonstrate compliance with the chromium compounds emissions limit 
specified in Table 2 to this subpart, you must conduct an annual 
performance test for chromium compounds emissions from each gas-fired 
glass-melting furnace (no later than 12 calendar months following the 
previous compliance test).
    (e) Following the initial performance or compliance test to 
demonstrate compliance with the PM, formaldehyde, phenol, and methanol 
emissions limits specified in Table 2 to this subpart, you must conduct 
a performance test to

[[Page 45335]]

demonstrate compliance with each of the applicable PM, formaldehyde, 
phenol, and methanol emissions limits in Sec.  63.1382 at least once 
every five years.

0
23. Section 63.1385 is amended by revising paragraphs (a)(5) and (6), 
redesignating paragraph (a)(10) as paragraph (a)(13), and adding 
paragraphs (a)(10) through (12) to read as follows:

Sec.  63.1385  Test methods and procedures.

    (a) * * *
    (5) Method 5 or Method 29 (40 CFR part 60, appendix A-3) for the 
concentration of total PM. When using Method 5, each run must consist 
of a minimum sample volume of 2 dry standard cubic meters (dscm). When 
using Method 29, each run must consist of a minimum sample volume of 3 
dscm. When measuring PM concentration using either Method 5 or 29, the 
probe and filter holder heating system must be set to provide a gas 
temperature no greater than 12014[deg]C (24825[emsp14][deg]F).
    (6) For measuring the concentration of formaldehyde, use one of the 
following test methods:
    (i) Method 318 (appendix A of this part). Each test run must 
consist of a minimum of 10 spectra.
    (ii) Method 316 (appendix A of this part). Each test run must 
consist of a minimum of 2 dry standard cubic meters (dscm) of sample 
volume.
* * * * *
    (10) For measuring the concentration of phenol, use Method 318 
(appendix A of this part). Each test run must consist of a minimum of 
10 spectra.
    (11) For measuring the concentration of methanol, use one of the 
following test methods:
    (i) Method 318 (appendix A of this part). Each test run must 
consist of a minimum of 10 spectra.
    (ii) Method 308 (appendix A of this part). Each test run must 
consist of a minimum of 2 hours.
    (12) Method 29 (40 CFR part 60, appendix A-8) for the concentration 
of chromium compounds. Each test run must consist of a minimum sample 
volume of 3 dscm.
* * * * *

0
24. Section 63.1386 is amended by revising paragraphs (a)(2) through 
(4), removing and reserving paragraph (b), revising paragraph (c), and 
adding paragraphs (d)(2)(x) and (xi), (f) and (g) to read as follows:

Sec.  63.1386  Notification, recordkeeping, and reporting requirements.

    (a) * * *
    (2) Notification that a source is subject to the standard, where 
the initial startup is before November 25, 2011.
    (3) Notification that a source is subject to the standard, where 
the source is new or has been reconstructed the initial startup is 
after November 25, 2011, and for which an application for approval of 
construction or reconstruction is not required;
    (4) Notification of intention to construct a new affected source or 
reconstruct an affected source; of the date construction or 
reconstruction commenced; of the anticipated date of startup; of the 
actual date of startup, where the initial startup of a new or 
reconstructed source occurs after November 25, 2011, and for which an 
application for approval or construction or reconstruction is required 
(See Sec.  63.9(b)(4) and (5));
* * * * *
    (c) Records and reports for a failure to meet a standard. (1) In 
the event that an affected unit fails to meet a standard, record the 
number of failures since the prior notification of compliance status. 
For each failure record the date, time, and duration of each failure.
    (2) For each failure to meet a standard record and retain a list of 
the affected source or equipment, an estimate of the volume of each 
regulated pollutant emitted over the standard for which the source 
failed to meet the standard, and a description of the method used to 
estimate the emissions.
    (3) Record actions taken to minimize emissions in accordance with 
Sec.  63.1382, including corrective actions to restore process and air 
pollution control and monitoring equipment to its normal or usual 
manner of operation.
    (4) If an affected unit fails to meet a standard, report such 
events in the notification of compliance status required by Sec.  
63.1386(a)(7). Report the number of failures to meet a standard since 
the prior notification. For each instance, report the date, time, and 
duration of each failure. For each failure the report must include a 
list of the affected units or equipment, an estimate of the volume of 
each regulated pollutant emitted over the standard, and a description 
of the method used to estimate the emissions.
    (d) * * *
    (2) * * *
    (x) Records of your cullet sampling or records of inspections from 
cullet providers.
    (xi) For each gas-fired glass-melting furnace that uses cullet, 
records of the daily average cullet percentage, and the 30-day rolling 
average percent cullet in the materials mix charged to the furnace. The 
initial daily average should be recorded on the compliance date and the 
first 30-day rolling average should be calculated 30 days after the 
compliance date.
* * * * *
    (f) Within 60 days after the date of completing each performance 
test (as defined in Sec.  63.2) required in this subpart, you must 
submit the results of the performance tests, including any associated 
fuel analyses, following the procedure specified in either paragraph 
(f)(1) or (2) of this section.
    (1) For data collected using test methods supported by the EPA's 
Electronic Reporting Tool (ERT) as listed on the EPA's ERT Web site 
(http://www.epa.gov/ttn/chief/ert/index.html), you must submit the 
results of the performance test to the EPA via the Compliance and 
Emissions Data Reporting Interface (CEDRI). CEDRI can be accessed 
through the EPA's Central Data Exchange (CDX) (http://cdx.epa.gov/epa_home.asp). Performance test data must be submitted in a file format 
generated through the use of the EPA's ERT. Alternatively, you may 
submit performance test data in an electronic file format consistent 
with the extensible markup language (XML) schema listed on the EPA's 
ERT Web site, once the XML schema is available. If you claim that some 
of the performance test information being submitted is confidential 
business information (CBI), you must submit a complete file generated 
through the use of the EPA's ERT or an alternate electronic file 
consistent with the XML schema listed on the EPA's ERT Web site, 
including information claimed to be CBI, on a compact disc, flash drive 
or other commonly used electronic storage media to the EPA. The 
electronic media must be clearly marked as CBI and mailed to U.S. EPA/
OAPQS/CORE CBI Office, Attention: Group Leader, Measurement Policy 
Group, C404-02, 4930 Old Page Rd., Durham, NC 27703. The same ERT or 
alternate file with the CBI omitted must be submitted to the EPA via 
the EPA's CDX as described earlier in this paragraph.
    (2) For data collected using test methods that are not supported by 
the EPA's ERT as listed on the EPA's ERT Web site, you must submit the 
results of the performance test to the Administrator at the appropriate 
address listed in Sec.  63.13.
    (g) All reports required by this subpart not subject to the 
requirements in paragraph (f) of this section must be sent to the 
Administrator at the appropriate address listed in Sec.  63.13. If 
acceptable to both the Administrator and the owner or

[[Page 45336]]

operator of a source, these reports may be submitted on electronic 
media. The Administrator retains the right to require submittal of 
reports subject to paragraph (f) of this section in paper format.

0
25. Section 63.1387 is amended by revising paragraph (a) and adding 
paragraph (c) to read as follows:

Sec.  63.1387  Compliance dates.

    (a) Compliance dates. You must comply with the emissions limits by 
the dates specified in Table 2 to this subpart.
* * * * *
    (c) At all times, you must operate and maintain any affected 
source, including associated air pollution control equipment and 
monitoring equipment, in a manner consistent with safety and good air 
pollution control practices for minimizing emissions. Determination of 
whether such operation and maintenance procedures are being used will 
be based on information available to the Administrator which may 
include, but is not limited to, monitoring results, review of operation 
and maintenance procedures, review of operation and maintenance 
records, and inspection of the source.

0
26. Section 63.1389 is added to read as follows:

Sec.  63.1389  Startups and shutdowns.

    (a) The provisions set forth in this subpart apply at all times.
    (b) You must not shut down items of equipment that are required or 
utilized for compliance with the provisions of this subpart during 
times when emissions are being, or are otherwise required to be, routed 
to such items of equipment.
    (c) Startup begins when the wool fiberglass glass-melting furnace 
has any raw materials added and reaches 50 percent of its typical 
operating temperature. Startup ends when molten glass begins to flow 
from the wool fiberglass glass-melting furnace. For cold-top electric 
furnaces, startup ends when the batch cover is established and the 
temperature of the glass batch-cover surface is below 
300[emsp14][deg]F.
    (d) Shutdown begins when the heat sources to the glass-melting 
furnace are reduced to begin the glass-melting furnace shut down 
process. Shutdown ends when the glass-melting furnace is empty or the 
contents are sufficiently viscous to preclude glass flow from the 
glass-melting furnace.
    (e) During periods of startup and shutdown in a cold-top furnace 
that is routed to a baghouse during normal operation, you must 
establish the batch cover and operate your furnace according to the 
following requirements during startup and shutdown:
    (1) You must keep records showing that you used only natural gas or 
other clean fuels to heat each furnace; and
    (2) Except after batch cover is established, you must keep records 
showing that you used only cullet as a raw material during the startup 
of each cold-top furnace; and
    (3) Once a batch cover is established and a control device can be 
safely operated, you must keep records showing that furnace emissions 
were controlled using air pollution control devices operated at the 
parameters established by the most recent performance test that showed 
compliance with the standard.
    (4) During periods of shutdown in a cold-top furnace, until the 
conditions above the glass reach a point at which the control device 
may be damaged if it continues to operate, you must keep records 
showing furnace emissions were controlled using air pollution control 
devices operated at the parameters established by the most recent 
performance test that showed compliance with the standard.
    (f) During both periods of startups and shutdowns for all furnace 
types other than cold-top furnaces, you must operate each furnace 
according to the following requirements:
    (1) You must record the type of fuel used to heat the furnace 
during startup and shutdown to demonstrate that you used only natural 
gas or other clean fuels; and
    (2) You must keep records showing that furnace emissions were 
controlled using air pollution control devices operated at the 
parameters established by the most recent performance test that showed 
compliance with the standard.
0
27. Table 1 to subpart NNN of part 63 is revised to read as follows:

  Table 1 to Subpart NNN of Part 63--Applicability of General Provisions (40 CFR Part 63, Subpart A) to Subpart
                                                       NNN
----------------------------------------------------------------------------------------------------------------
                                                                  Applies to subpart
   General provisions  citation             Requirement                  NNN?                 Explanation
----------------------------------------------------------------------------------------------------------------
Sec.   63.1(a)(1)-(5).............  Applicability.............  Yes..................
Sec.   63.1(a)(6).................  ..........................  Yes..................
Sec.   63.1(a)(7)-(9).............  ..........................  No...................  [Reserved].
Sec.   63.1(a)(10)-(12)...........  ..........................  Yes..................
Sec.   63.1(b)(1).................  Initial Applicability       Yes..................
                                     Determination.
Sec.   63.1(b)(2).................  ..........................  No...................  [Reserved].
Sec.   63.1(b)(3).................  ..........................  Yes..................
Sec.   63.1(c)(1)-(2).............  ..........................  Yes..................
Sec.   63.1(c)(3)-(4).............  ..........................  No...................  [Reserved].
Sec.   63.1(c)(5)-(e).............  ..........................  Yes..................
Sec.   63.2.......................  Definitions...............  Yes..................
Sec.   63.3.......................  Units and Abbreviations...  Yes..................
Sec.   63.4(a)(1)-(2).............  Prohibited Activities.....  Yes..................
Sec.   63.4(a)(3)-(5).............  ..........................  No...................  [Reserved].
Sec.   63.4(b)-(c)................  ..........................  Yes..................
Sec.   63.5(a)-(b)(2).............  Construction/               Yes..................
                                     Reconstruction
                                     Applicability.
Sec.   63.5(b)(3)-(4).............  ..........................  Yes..................
Sec.   63.5(b)(5).................  ..........................  No...................  [Reserved].
Sec.   63.5(b)(6).................  ..........................  Yes..................
Sec.   63.5(c)....................  ..........................  No...................  [Reserved].
Sec.   63.5(d)....................  Application for Approval    Yes..................
                                     of Construction or
                                     Reconstruction.
Sec.   63.5(e)....................  Approval of Construction/   Yes..................
                                     Reconstruction.
Sec.   63.5(f)....................  Approval of Construction/   Yes..................
                                     Reconstruction Based on
                                     State Review.

[[Page 45337]]

 
Sec.   63.6(a)-(d)................  Compliance with Standards   Yes..................
                                     and Maintenance
                                     Requirements.
Sec.   63.6(e)(1)(i)..............  General Duty to Minimize    No...................  See Sec.   63.1382(b) for
                                     Emissions.                                         general duty
                                                                                        requirement.
Sec.   63.6(e)(1)(ii).............  Requirement to Correct      No...................  Sec.   63.1382(b)
                                     Malfunctions As Soon As                            specifies additional
                                     Possible.                                          requirements.
Sec.   63.6(e)(1)(iii)............  ..........................  Yes..................
Sec.   63.6(e)(2).................  ..........................  No...................  [Reserved].
Sec.   63.6(e)(3).................  Startup, Shutdown,          No...................  Startups and shutdowns
                                     Malfunction (SSM) Plan.                            addressed in Sec.
                                                                                        63.1388.
Sec.   63.6(f)(1).................  SSM Exemption.............  No...................
Sec.   63.6(f)(2)-(3).............  Methods for Determining     Yes..................
                                     Compliance.
Sec.   63.6(g)....................  Use of an Alternative       Yes..................
                                     Nonopacity Emission
                                     Standard.
Sec.   63.6(h)(1).................  SSM Exemption.............  No...................
Sec.   63.6(h)(2)-(j).............  ..........................  Yes..................
Sec.   63.7(a)-(d)................  ..........................  Yes..................
Sec.   63.7(e)(1).................  Performance Testing.......  No...................  See Sec.   63.1382(b).
Sec.   63.7(e)(2)-(e)(4)..........  ..........................  Yes..................
Sec.   63.7(f)....................  Alternative Test Method...  Yes..................
Sec.   63.7(g)(1).................  Data Analysis.............  Yes..................
Sec.   63.7(g)(2).................  ..........................  No...................  [Reserved].
Sec.   63.7(g)(3).................  ..........................  Yes..................
Sec.   63.7(h)....................  Waiver of Performance Test  Yes..................
Sec.   63.8(a)-(b)................  Monitoring Requirements...  Yes..................
Sec.   63.8(c)(1)(i)..............  General Duty to Minimize    No...................  See Sec.   63.1382(c) for
                                     Emissions and CMS                                  general duty
                                     Operation.                                         requirement.
Sec.   63.8(c)(1)(ii).............  ..........................  Yes..................
Sec.   63.8(c)(1)(iii)............  Requirement to Develop SSM  No...................
                                     Plan for CMS.
Sec.   63.8(d)(1)-(2).............  Quality Control Program...  Yes..................
Sec.   63.8(d)(3).................  Written Procedures for CMS  Yes, except for last
                                                                 sentence, which
                                                                 refers to SSM plan.
                                                                 SSM plans are not
                                                                 required.
Sec.   63.8(e)-(g)................  ..........................  Yes..................
Sec.   63.9(a)....................  Notification Requirements.  Yes..................
Sec.   63.9(b)(1)-(2).............  Initial Notifications.....  Yes..................
Sec.   63.9(b)(3).................  ..........................  No...................  [Reserved].
Sec.   63.9(b)(4)-(j).............  ..........................  Yes..................
Sec.   63.10(a)...................  Recordkeeping and           Yes..................
                                     Reporting Requirements.
Sec.   63.10(b)(1)................  General Recordkeeping       Yes..................
                                     Requirements.
Sec.   63.10(b)(2)(i).............  Recordkeeping of            No...................
                                     Occurrence and Duration
                                     of Startups and Shutdowns.
Sec.   63.10(b)(2)(ii)............  Recordkeeping of            No...................  See Sec.   63.1386 (c)(1)
                                     Malfunctions.                                      through (3) for
                                                                                        recordkeeping of
                                                                                        occurrence and duration
                                                                                        and actions taken during
                                                                                        a failure to meet a
                                                                                        standard.
Sec.   63.10(b)(2)(iii)...........  Maintenance Records.......  Yes..................
Sec.   63.10(b)(2)(iv)-(v)........  Actions Taken to Minimize   No...................
                                     Emissions During SSM.
Sec.   63.10(b)(2)(vi)............  Recordkeeping for CMS       Yes..................
                                     Malfunctions.
Sec.   63.10(b)(2)(vii)-(xiv).....  Other CMS Requirements....  Yes..................
Sec.   63.10(b)(3)................  Recordkeeping Requirements  Yes..................
                                     for Applicability
                                     Determinations.
Sec.   63.10(c)(1)-(6)............  Additional Recordkeeping    Yes..................
                                     Requirements for Sources
                                     with CMS.
Sec.   63.10(c)(7)-(8)............  Additional Recordkeeping    Yes..................
                                     Requirements for CMS--
                                     Identifying Exceedances
                                     and Excess Emissions.
Sec.   63.10(c)(9)................  ..........................  No...................  [Reserved].
Sec.   63.10(c)(10)-(11)..........  ..........................  No...................  See Sec.   63.1386 for
                                                                                        recordkeeping of
                                                                                        malfunctions.
Sec.   63.10(c)(12)-(c)(14).......  ..........................  Yes..................
Sec.   63.10(c)(15)...............  Use of SSM Plan...........  No...................
Sec.   63.10(d)(1)-(4)............  General Reporting           Yes..................
                                     Requirements.
Sec.   63.10(d)(5)................  SSM Reports...............  No...................  See Sec.
                                                                                        63.1386(c)(iii) for
                                                                                        reporting of
                                                                                        malfunctions.

[[Page 45338]]

 
Sec.   63.10(e)-(f)...............  Additional CMS Reports      Yes..................
                                     Excess Emission/CMS
                                     Performance Reports COMS
                                     Data Reports
                                     Recordkeeping/Reporting
                                     Waiver.
Sec.   63.11(a)-(b)...............  Control Device              No...................  Flares will not be used
                                     Requirements                                       to comply with the
                                     Applicability Flares.                              emissions limits.
Sec.   63.11(c)...................  Alternative Work Practice   Yes..................
                                     for Monitoring Equipment
                                     for Leaks.
Sec.   63.11(d)...................  Alternative Work Practice   Yes..................
                                     Standard.
Sec.   63.11(e)...................  Alternative Work Practice   Yes..................
                                     Requirements.
Sec.   63.12......................  State Authority and         Yes..................
                                     Delegations.
Sec.   63.13......................  Addresses.................  Yes..................
Sec.   63.14......................  Incorporation by Reference  Yes..................
Sec.   63.15......................  Availability of             Yes..................
                                     Information/
                                     Confidentiality.
Sec.   63.16......................  Performance Track           Yes..................
                                     Provisions.
----------------------------------------------------------------------------------------------------------------

0
28. Subpart NNN is amended by adding Table 2 to read as follows:

                    Table 2 to Subpart NNN of Part 63--Emissions Limits and Compliance Dates
----------------------------------------------------------------------------------------------------------------
                                      And you commenced    Your emission limits
       If your source is a:             construction:            are: \1\          And you must comply by: \2\
----------------------------------------------------------------------------------------------------------------
1. Glass-melting furnace..........  On or before March     0.5 lb PM per ton of  June 14, 2002.
                                     31, 1997.              glass pulled \3\.
2. Glass-melting furnace..........  After March 31, 1997   0.5 lb PM per ton of  June 14, 1999.
                                     but on or before       glass pulled \3\.
                                     November 25, 2011.
3. Glass-melting furnace..........  On or before November  0.33 lb PM per ton    July 31, 2017.
                                     25, 2011.              of glass pulled.
4. Glass-melting furnace..........  After November 25,     0.33 lb PM per ton    July 29, 2015.\4\
                                     2011.                  of glass pulled.
5. Gas-fired glass-melting furnace  On or before November  0.00025 lb chromium   July 31, 2017.
                                     25, 2011.              compounds per ton
                                                            of glass pulled.
6. Gas-fired glass-melting furnace  After November 25,     0.00025 lb chromium   July 29, 2015.\4\
                                     2011.                  compounds per ton
                                                            of glass pulled.
7. Rotary spin manufacturing line.  On or before March     1.2 lb Formaldehyde   June 14, 2002.
                                     31, 1997.              per ton of glass
                                                            pulled.
8. Rotary spin manufacturing line.  After March 31, 1997.  0.8 lb Formaldehyde   June 14, 1999.
                                                            per ton of glass
                                                            pulled.
9. Flame-attenuation line           After March 31, 1997   7.8 lb formaldehyde   June 14, 1999.
 manufacturing a heavy-density       but on or before       per ton of glass
 product.                            November 25, 2011.     pulled \3\.
10. Flame-attenuation line          On or before March     6.8 lb formaldehyde   June 14, 2002.
 manufacturing a pipe product.       31, 1997.              per ton of glass
                                                            pulled \3\.
11. Flame-attenuation line          After March 31, 1997   6.8 lb formaldehyde   June 14, 1999.
 manufacturing a pipe product.       but before November    per ton of glass
                                     25, 2011.              pulled \3\.
12. Flame-attenuation line          On or before November  1.4 lb phenol per     July 31, 2017.
 manufacturing any product.          25, 2011.              ton of glass pulled.
                                                           5.6 lb formaldehyde
                                                            per ton of glass
                                                            pulled.
                                                           0.50 lb methanol per
                                                            ton of glass pulled.
13. Flame-attenuation line          After November 25,     0.44 lb phenol per    July 29, 2015.\4\
 manufacturing any product.          2011.                  ton of glass pulled.
                                                           2.6 lb formaldehyde
                                                            per ton of glass
                                                            pulled.
                                                           0.35 lb methanol per
                                                            ton of glass pulled.
----------------------------------------------------------------------------------------------------------------
\1\ The numeric limits do not apply during startup and shutdown.
\2\ Existing sources must demonstrate compliance by the compliance dates specified in this table. New sources
  have 180 days after the applicable compliance date to demonstrate compliance.
\3\ This limit does not apply after July 31, 2017.
\4\ Or initial startup, whichever is later.

[FR Doc. 2015-16643 Filed 7-28-15; 8:45 am]
 BILLING CODE 6560-50-P