v-xEPA
United! States
Environmental Protection
Agency
Office of Air Quality
Planning and Standards
Research Triangle Park NC 27711
EPA-45Q/3-85-022b
July 1989
Air
Polymeric
Coating Of
Supporting
Substrates—
Background
Information for
Promulgated
Standards
Final
EIS
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POLYMERIC COATING OF SUPPORTING SUBSTRATES--
BACKGROUND INFORMATION FOR PROMULGATED STANDARDS
Emission Standards Division
U. S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711
July 1989
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This report has been reviewed by the Emission Standards Division of the
Office of Air Quality Planning and Standards, EPA, and approved for
publication. Mention of trade names or commercial products is not
intended to constitute endorsement or recommendation for use. Copies of
this report are available through the Library Services Office (MD-35),
U. S. Environmental Protection Agency, Research Triangle Park, North
Carolina 27711, or from National Technical Information Services,
5285 Port Royal Road, Springfield, Virginia 22161.
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ENVIRONMENTAL PROTECTION AGENCY
Background Information
and Draft
Environmental Impact Statement
for the Polymeric Coating of Supporting Substrates
Prepared by:
JacXR. Farmer / (D*fte)'
Director, Emission Standards Division
U. S. Environmental Protection Agency
Research Triangle Park, N.C. 27711
1. The promulgated standards of performance will limit emissions of volatile
organic compounds (VOC) from new, modified, and reconstructed facilities
that perform polymeric coating of supporting substrates. Section 111 of
the Clean Air Act (42 U.S.C. 7411), as amended, directs the Administrator
to establish standards of performance for any category of new stationary
source of air pollution that "... causes or contributes significantly
to air pollution which may reasonably be anticipated to endanger public
health or welfare."
2. Copies of this document have been sent to the following Federal
Departments: Labor, Health and Human Services, Defense, Transportation,
Agriculture, Commerce, and Interior; the National Science Foundation; the
Council on Environmental Quality; State and Territorial Air Pollution
Program Administrators, EPA Regional Administrators; Association of Local
Air Pollution Control Officials; Office of Management and Budget; and
other interested parties.
3. For additional information contact:
Ms. Laura Butler or Mr. Doug Bell
Standards Development Branch (MD-13)
U. S. Environmental Protection Agency
Research Triangle Park, N.C. 27711
Telephone: (919) 541-5267
4. Copies of this document may be obtained from:
U.S. EPA Library (MD-35)
Research Triangle Park, N.C. 27711
Telephone: (919) 541-2777
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
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TABLE OF CONTENTS
Page
CHAPTER 1 SUMMARY 1_1
1.1 SUMMARY OF CHANGES SINCE PROPOSAL 1-1
1.2 SUMMARY OF IMPACTS OF PROMULGATED ACTION 1-8
CHAPTER 2 SUMMARY OF PUBLIC COMMENTS 2-1
2.1 SELECTION OF THE SOURCE CATEGORY 2-6
2.2 AFFECTED FACILITY 2-10
2.3 SELECTION OF BDT AND EMISSION LIMITS 2-12
2.4 CONTROL COSTS 2-43
2.5 ENVIRONMENTAL IMPACTS 2-50
2.6 ECONOMIC IMPACTS 2-52
2.7 COMPLIANCE 2-56
2.8 TEST METHODS AND MONITORING 2-59
2.9 REPORTING AND RECORDKEEPING 2-62
2.10 WORDING OF THE REGULATION 2-63
2.11 MODIFICATION/RECONSTRUCTION 2-73
2.12 REFERENCES FOR CHAPTER 2 2-75
TABLE 2-1
TABLE 2-2
TABLE 2-3
LIST OF TABLES
LIST OF COMMENTERS ON PROPOSED STANDARDS OF
PERFORMANCE FOR NEW STATIONARY SOURCES;
POLYMERIC COATING OF SUPPORTING SUBSTRATES,
SUMMARY OF TOTAL ENCLOSURE
CRITERIA
AVERAGE AND INCREMENTAL COST EFFECTIVENESS FOR MODEL
COATING OPERATIONS
2-2
2-15
2-24
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1. SUMMARY
On April 30, 1987, the U. S. Environmental Protection Agency (EPA)
proposed new source performance standards (NSPS) for the polymeric coating
of supporting substrates (52 FR 15906) under authority of Section 111 of
the Clean Air Act. Public comments were requested on the proposal
published in the Federal Register. A total of 24 comments were submitted
during the comment period, including 21 from industry, 2 from trade
associations, and 1 from a State agency. The comments that were
submitted, along with responses to these comments, are summarized in this
document. The summary of comments and responses serves as the basis for
the revisions made to the standards between proposal and promulgation.
1.1 SUMMARY OF CHANGES SINCE PROPOSAL
In response to the public comments and as a result of EPA
reevaluation, several changes have been made to the standards since
proposal. In addition, portions of the final regulation were reworded and
reorganized to clarify the intent of the rule. The more significant
changes, which are categorized under the section headings in the
regulation, are summarized below.
1.1.1 Applicability and Designation of Affected Facility
1.1.1.1 Coating Mix Preparation Equipment. A change was made to the
definition of coating mix preparation equipment to include only mixing
vessels, and not mills, holding tanks, or other equipment used in the
preparation of polymeric coatings. Equipment other than mixers was
included in the affected facility definition in the proposed standards
because it was believed that the controls required for mixers could be
easily applied to other types of mix equipment. However, based on a
reexamination of the information gathered during the development of the
standards and based on the information provided by a commenter, only
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mixing vessels are Included In the affected facility in the promulgated
standards.
1.1.1.2 Exclusions. The regulation has been revised to state
explicitly that graphic arts facilities are not covered by the
standards. The exclusion of paper, plastic film, metallic foil, and metal
coil coaters has been clarified by revising the definition of "polymeric
coating of supporting substrates." The exclusion of leather finishers has
been clarified by removing the reference to leather in the definition of
"web coating." Comments from the leather, graphic arts, and paper coating
Industries revealed that it was unclear if the proposed standards were
applicable to these particular industries. The EPA did not study these
industries and did not intend for the standards to be applicable to these
industries. An exemption also was added for waterborne coatings because
use of these coatings may be incompatible with the available control
technologies.
1.1.2 Standards for Volatile Organic Compounds (VOC)
1.1.2.1 Coating Mix Preparation Equipment—VOC Use at Least
130 mg/yr. The standards for mixing vessels serving coating operations
that use at least 130 cubic meters per year (Mg/yr) (144 tons per year
[tons/yr]) of VOC have been revised consistent with the application of
best demonstrated technology (BOT) in actual practice. The proposed
standards required "venting all VOC emissions to a 95 percent efficient
control device," which implies a 100 percent capture efficiency. The
promulgated standards require that mixing vessels be covered during mixing
and vented to a 95 percent efficient control device. Allowances for
opening the covers during periods of legitimate need are included in the
standards.
In addition, a provision has been added to the standards that allows
the use of covers alone on mix equipment at modified or reconstructed
affected facilities unless there is concurrent construction of a control
device. This change was made because 1t is not certain that the existing
control devices at all modified/reconstructed facilities would have
sufficient capacity in reserve to control emissions from the mix
equipment. As stated at proposal, the installation and use of a dedicated
control device for mix equipment emissions is not cost effective.
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Therefore, the standards have been revised to ensure that control of mix
equipment emissions is cost effective.
1.1.2.2 Coating Mix Preparation Equipment—VOC Use at Least 95 Mq/yr
But Less Than 130 Mq/yr. A change has been made to the standards for
mixing vessels serving coating operations that use at least 95 Mg/yr (105
tons/yr) but less than 130 Mg/yr (144 tons/yr) of VOC. The proposed
standards required each piece of affected coating mix preparation
equipment to have a vapor-tight cover with a conservation vent set at
17.2 kilopascals (2.5 pounds per square inch gauge). The promulgated
standards require a cover that meets specified requirements. This change
was made because there is no significant increase in efficiency gained by
using a vapor-tight cover with a conservation vent instead of a simple
tight-fitting cover. The chief benefit of conservation vents is the
control of "breathing losses," which result from diurnal temperature
changes. However, mix equipment is not normally exposed to such
temperature changes.
1.1.2.3 Coating Operation. The standards for the coating operation
have been revised to require a 90 percent overall emission reduction
rather than 93 percent as proposed. This change was made based on a
reevaluation of the feasibility of total enclosures in this industry and
of the test data available to support the standards. In general, EPA
concluded that while facilities that can use total enclosures and
95 percent efficient control devices may achieve 93 percent or greater
overall control, the use of this technology may not be available if
EPA-prescribed total enclosures cannot be used in existing plants. It was
determined that 90 percent overall control is universally achievable, and
the standards have been set at this level.
The standards also have been revised to include an alternative
standard, i.e., the use of a total enclosure and 95 percent efficient
control device, as an alternative to the 90 percent overall emission
reduction standard. While this alternative was allowed at proposal as an
alternative means of compliance with the emission reduction standard, EPA
has now decided to Include it as an alternative standard in order to
clarify the intent of the rule. This change is not a revision to the
substance of the proposed rule.
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1.1.3 Compliance Provisions
1.1.3.1 Total enclosure specifications. In order to provide sources
with guidelines for a total enclosure of the coating operation, specifica-
tions have been added that limit the total area of the natural draft
openings in the enclosure, specify the minimum allowable distance between
the openings and the sources of VOC, and require the maintenance of an
average inward face velocity of at least 3,600 meters per hour (m/h)
(200 feet per minute [ft/min]) across the openings. These restrictions
are necessary to ensure complete containment of the VOC emissions from the
coating operation. Flexibility has been maintained by allowing enclosures
not meeting the requirements to be considered for approval by the
Administrator on a case-by-case basis. Test procedures and monitoring,
recordkeeping, and reporting requirements for the use of total enclosures
also have been added.
1.1.3.2 Coating Operation Compliance Methods. The final standards
have been revised to clarify that the use of certain equipment, i.e., a
total enclosure and a 95 percent efficient control device, are available
as an alternate standard to the 90 percent emission reduction standard.
In other words, the owner or operator may choose to comply with either the
emission reduction standard or the alternative standard. In addition, the
compliance provisions for coating operations meeting the emission
reduction standard have been revised to clarify that owners or operators
may demonstrate compliance by any of the applicable methods. The option
of performing a one-time, short-term (3- to 7-day) material balance
followed by continuous monitoring was added as an optional compliance
method. This option may be attractive at facilities that cannot or do not
want to conduct the detailed continuous monthly measurements that are
required for the other liquid material balance option.
1.1.3.3 Equation 3. An error in Equation 3 (§ 60.743(b)(4)), which
is used to determine the efficiency of the vapor capture system, has been
corrected in the promulgated standards. The terms Qbl- and Cb1 have been
changed to Qd1 and Cd1, respectively.
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1.1.4 Monitoring Requirements
1.1.4.1 Accuracy Requirements for Temperature Monitoring. For
consistency with other VOC control regulations, the accuracy requirements
for temperature monitoring have been changed. In the proposed regulation,
the monitoring device was required to be accurate within ±2.5 Celsius
degrees (±4.2 Fahrenheit degrees). In the promulgated regulation, the
monitoring device is required to be accurate to within ±1 percent of the
temperature being measured in Celsius degrees.
1.1.4.2 VOC Concentration. The monitoring requirement for carbon
adsorbers has been revised to require devices that indicate and record the
"concentration level of organic compounds" instead of the "VOC
concentration in parts per million by volume." Although many monitors
give readings in terms of parts per million by volume, the revision is
intended to reflect the fact that EPA has not developed performance
specifications or other quality assurance procedures to ensure the
accuracy of such monitors. However, units are available that are
sufficiently precise to allow assessment of operation and maintenance
practices by comparing monitor data with the baseline value established
during the performance test.
1.1.4.3 Consistency of Monitoring and Performance Testing
Provisions. The monitoring and performance testing provisions for fixed
bed carbon adsorption systems have been revised to represent more
accurately the performance of multiple-bed systems. Performance tests are
the direct means of determining the compliance status of an affected
facility and serve as the basis for legal enforcement actions against
noncomplying sources. In contrast, the monitoring devices required by
these standards serve only as indicators of control device performance to
aid enforcement agencies in targeting inspections and performance tests
toward potential violators. The revised procedures will ensure that the
performance test runs and averaging periods for monitoring will parallel
the complete adsorption cycles of the individual adsorber vessels or the
system's complete sequential rotation through the adsorption cycles of all
the vessels. Use of a testing or monitoring period that does not
correspond to an Integral number of actual adsorber vessel cycles or
system rotations could bias the results slightly in either direction.
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Efficiencies would be biased high if the test run or monitoring period did
not include the elevated emissions typical at the beginning and end of a
vessel's adsorption cycle; efficiencies would be biased low if the period
included a disproportionate number of these emission peaks.
the performance testing provisions for carbon adsorption systems
included in the standards at proposal did not specifically index the test
period to discrete adsorber vessel cycles or system rotations. Rather,
each of the three requisite performance test runs was required to be a
minimum of 30 minutes duration. While this requirement would have allowed
the performance test runs to correspond to individual adsorber vessel
cycles or system rotations that were at least 30 minutes in duration, it
was not mandatory. Because adsorption cycles in different systems can
range from several minutes to several hours, performance tests based only
on 30-minute runs could be biased somewhat in either direction. The
proposed performance testing provisions would have resulted in adequate
determinations of the performance of these systems, but the final
provisions provide for improved accuracy.
The revised carbon adsorption system performance testing provisions
include separate requirements for systems with a single common exhaust
stack and for systems with individual stacks for each adsorber vessel.
The EPA believes that a common exhaust stack allows simpler performance
testing that is more representative of the entire system's performance but
has included provisions for individual exhaust stacks because this is
currently the more typical configuration.
For adsorption systems with a common exhaust stack serving all the
adsorber vessels, the final performance testing provisions require that
the system be tested as a whole. Three test runs are required; each run
must correspond to one or more complete rotations through the sequential
adsorption cycles of all the adsorber vessels.
For adsorption systems with individual exhaust stacks, the final
performance testing provisions require that each adsorber vessel be tested
individually. Three test runs are required for each vessel; each run must
correspond to one or more complete adsorption cycles. A procedure has
been added to the compliance provisions for computing a system efficiency
from the individual adsorber vessel efficiencies.
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The final performance testing provisions are likely to result in
somewhat increased testing costs in the case of a multiple-bed system
because each test run must include at least one cycle for each bed.
However, this increased cost would be very small relative to the control
system cost and is reasonable considering the increased accuracy that will
result.
The final adsorber monitoring provisions parallel the final
performance testing provisions. Again, separate provisions apply to
systems with a common exhaust stack and those with individual stacks. No
increase in monitoring costs is anticipated.
For adsorption systems with a common exhaust stack, a monitoring
device must be installed on the common exhaust stack and one also may be
installed on the common inlet duct. The owner or operator must report
each occurrence when the average emission level or system efficiency
(depending on whether only the outlet or both the inlet and outlet gas
streams are monitored) over three successive system rotations varies
outside the specified range.
For adsorption systems with individual vessel exhaust stacks, a
monitoring device must be installed on each individual exhaust stack, and
a monitoring device also may be installed on the common inlet duct or on
each individual inlet duct. Each adsorber vessel must be monitored for a
minimum of one complete adsorption cycle per day. A 3-day rolling average
emission level or efficiency for each vessel (depending on whether only
the outlet or both the inlet and outlet gas streams are monitored) must be
computed each day from the daily averages, and these 3-day rolling
averages must be reported when they vary outside the specified ranges.
1.1.4.4 General Wording. The section was reorganized for clarity,
and wording has been added to specify clearly that monitors must be in
place and operating during all performance tests.
1.1.5 Test Methods and Procedures
Because Method 25A is not appropriate for determining the efficiency
of a control device when the constitution of the gas stream varies from
the inlet to the outlet (e.g., when an incinerator is used), Method 25 has
been added for determining VOC concentrations, and is required when an
incinerator is used unless it is demonstrated to be technically infeasible
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under site-specific test conditions. The use of Method 25A is still
allowed when conditions are appropriate. In addition, Method 18 has been
included as a method to determine VOC concentration.
1.1.6 Alternative Means of Emission Limitation
Provisions have been added that allow a source to obtain approval
from the Administrator for an alternative to simple covers for controlling
VOC emissions from affected coating mix preparation equipment serving
coating lines using at least 95 Mg/yr (105 tons/yr) of VOC but less than
130 Mg/yr (144 tons/yr) of VOC or from equipment that is part of a
facility modified or reconstructed without concurrent construction of a
new control device. Provisions also have been added to allow facilities
to submit alternate total enclosure designs for the Administrator's
approval.
1.1.7 Reporting and Recordkeeping
1.1.7.1 Annual VOC Use. A requirement has been added to report when
actual annual VOC use exceeds the applicable cutoff. The proposed
standards required a report only when the estimated annual VOC use exceeds
the cutoff.
1.1.7.2 Monitoring Variations. A requirement has been added to
maintain records of all 3-hour (or applicable carbon adsorption system
rotations) periods during actual coating operations when the variations
specified in § 60.747(d)(l) through (6) occur, as well as to report such
periods. The reporting requirements have been revised to require
quarterly reports of exceedances. If none of the variations specified in
§ 60.747(d)(l)-(6) occur, a semiannual statement certifying this fact must
be submitted. This requirement has been added under § 60.747(d)(7).
1.2 SUMMARY OF IMPACTS OF PROMULGATED ACTION
1.2.1 Alternatives to Promulgated Action
The regulatory alternatives are discussed in Chapter 6 of the
Volume I background information document (BID) for the proposed standards
(EPA-450/3-85-022a). These regulatory alternatives reflect the different
levels of emission control from which one was selected that represents
BDT, considering costs, nonair quality health, and environmental, energy,
and economic impacts, for facilities performing polymeric coating of
supporting substrates. A new regulatory alternative, IIA, was developed
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post-proposal and represents a 90 percent overall level of control. This
alternative is identical to Regulatory Alternative II except that the
costs associated with total enclosures (from Regulatory Alternative III)
replace the partial enclosure costs. This change was made to represent
those facilities that cannot install and operate total enclosures as
defined in the final regulation. However, it more accurately reflects the
costs of the emission capture technology that the industry can (and
probably will) use.
1.2.2 Environmental Impacts of Promulgated Action
The environmental impacts projected at proposal are discussed in
Chapter 7 and Appendix B of the Volume I BIO. Because it is expected that
facilities will choose to comply with the coating operation standards by
means of the alternative standard, and thus achieve at least 93 percent
overall control, the environmental impacts have not changed since
proposal. Therefore, the Volume I BID becomes the final Environmental
Impact Statement for the promulgated standards.
1.2.3 Energy and Economic Impacts of the Promulgated Action
The energy Impacts of the proposed standards were evaluated in
Chapter 7 of the Volume I BID. It was determined that the control
technologies that are the basis for the regulatory alternatives have a
negligible effect on the energy requirements for facilities performing
polymeric coating of supporting substrates. Therefore, a negligible
energy impact was attributed to the proposed standards; this determination
remains unchanged for the final standards.
The economic impacts of the proposed standards were evaluated in
Chapter 9 of the Volume I BID. These impacts remain the same.
1.2.4 Other Considerations
1.2.4.1 Irreversible and Irretrievable Commitment of Resources. The
Volume I BID concluded in Chapter 7 that the regulatory alternatives will
result in the irreversible and irretrievable commitment of energy
resources. However, this increased energy demand for pollution control is
insignificant compared to the total energy demand of the production
line. No changes to these estimated impacts have occurred since proposal.
1.2.4.2 Environmental and Energy Impacts of Delayed Standards.
There is no significant benefit to be achieved from delaying the
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standards, as discussed in Chapter 7 of the Volume I BID. No changes in
the potential effects of delaying the standards have occurred since
proposal of the standards.
1.2.4.3 Urban and Community Impacts. These standards will have a
positive impact on urban areas and communities because of decreased VOC
emissions. There should be no decrease in employment in urban areas and
communities because the economic analysis indicated that the standards
would have little impact on retail price or profit.
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2. SUMMARY OF PUBLIC COMMENTS
Twenty-four letters commenting on the proposed standards and the
Volume I BID for the proposed standards were received. (One of these
simply corrected a minor error in an earlier letter.) A list of com-
menters, their affiliations, and the EPA document number assigned to their
correspondence is given in Table 2-1. No one requested to speak at a
public hearing; thus, none was held.
Docket items IV-D-11 through IV-D-24 were received after the close of
the public comment period. Nine of these commenters (IV-D-15, IV-D-17,
IV-D-18, IV-D-19, IV-D-20, IV-D-21, IV-D-22, IV-D-23, and IV-D-24)
petitioned for a reopening of the comment period so that EPA could
consider a separate textile subcategory. The EPA decided not to
officially reopen the comment period but did consider these late comments
in developing the final standards. In addition, EPA met with several
members of the American Textile Manufacturers Institute, Inc. (ATMI) at
their request to allow them to present followup information on their
public comments. This meeting is summarized in Docket Item IV-E-21.
Eight commenters (IV-D-11, IV-D-12, and IV-D-17, IV-D-18, IV-D-19,
IV-D-21 and IV-D-22, and IV-D-23) expressed their support for the comments
in Docket Item IV-D-7 or IV-D-15 as did ATMI members when they met with
EPA (IV-E-21). Docket Item IV-D-7 is a letter from the ATMI. Docket
Item IV-D-15, which addresses some of the same issues as Docket
Item IV-D-7, is from ATMI and the United States Industrial Fabrics
Institute (USIFI). The supporting commenters are referenced below only if
their comments expanded upon an issue discussed in IV-D-7 or IV-D-15 or
raised a new issue.
The comments and EPA's responses are discussed according to the
following topics:
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TABLE 2-1. LIST OF COMMENTERS ON PROPOSED STANDARDS OF PERFORMANCE
FOR NEW STATIONARY SOURCES: POLYMERIC COATING OF SUPPORTING SUBSTRATES
Docket
item No.a Commenter/affiliation
IV-D-1 Mr. E. W. Karger
Manager, PEPP
The Gates Rubber Company
999 South Broadway
Post Office Box 5887
Denver, Colorado 80217
IV-D-2 Mr. Frank H. Rutland
Technical Director
Leather Industries of America, Inc.
2501 M. Street, N.W.
Washington, D.C. 20037
IV-D-3 Mr. Roger D. Meadows
Vice President, Operations
Printing and Textile Products
DAY International
Post Office Box 360
Waynesville, North Carolina 28786
IV-D-4 Mr. Ray C. Woodcock, CIH
DAY International
Post Office Box 360
Waynesville, North Carolina 28786
(Correction to p. 5 of IV-D-3)
IV-D-5 Mr. Samuel I. Gutter
Attorney for W. R. Grace and Company
Polyfibron Division
Sidley and Austin
1722 Eye Street, N.W.
Washington, D.C. 20006
IV-D-6 Mr. M. F. Tanchuk
Environmental Engineer
Corporate Environmental Control Department
Reynolds Aluminum
Reynolds Metals Company
Richmond, Virginia 23261
IV-D-7 Ms. Maggie Dean
Director, Safety, Health and Environment
American Textile Manufacturers Institute, Inc.
1101 Connecticut Avenue, N.W.
Suite 300
Washington, D.C. 20036
~~~~(continued)
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TABLE 2-1. (continued)
Docket
Item No.a Commenter/affiliation
IV-D-8 Mr. V. A. D'Ippolito
Air Quality Coordinator
1CI Americas, Inc.
Wilmington, Delaware 19897
IV-D-9 Mr. William Juris, P.E.
Engineering Section
Division of Air Pollution Control
State of Ohio Environmental Protection Agency
Post Office Box 1049, 1800 Water Mark Drive
Columbus, Ohio 43266-0149
IV-D-10 Mr. Paul F. Cash
Manager, Environmental Control
Mobil Chemical Company
211 College Road East
Princeton Forrestal Center
Princeton, New Jersey 08540
IV-D-11 Mr. R. F. Cook
President
WestPoint Pepperell
Industrial Fabrics Division
Post Office Box 71
West Point, Georgia 31833
IV-D-12 Harold E. Sells
Managing Director
Coated Fabrics Division
American Recreation Products
500 Orchard Street
New Haven, Missouri 63068
IV-D-13 Jerry Stenner
President
James R. Ferron
Technical Director
Excello Fabric Finishers Incorporated
Box 711
810 South Second Street
Coshocton, Ohio 43812
IV-D-14 Robert Naujelis
Regulatory Affairs Manager
Paxar
530 Route 303
Orangeburg, New York 10962
"(continued)
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TABLE 2-1. (continued)
Docket
item No.a Commenter/affiliation
IV-D-15 Maggie Dean
Director, Safety, Health & Environment
American Textile Manufacturer's Institute, Inc.
1101 Connecticut Avenue, NW
Suite 300
Washington, D.C. 20036
and
Marcia Thomson
Director of Public Affairs
United States Industrial Fabrics Institute
IV-D-16 James F. Murphy, Jr.
Assistant Vice President
Polyfibron Division
W. R. Grace and Company
55 Hayden Avenue
Lexington, Massachusetts 02173
IV-D-17 Fred T. Eslick
General Manager, Engineering, Transportation,
and Plastics
American Thread Company
.Post Office Box 880
Old Fort, North Carolina 28762
IV-D-18 Marguerita C. Hindle
Vice President
Research and Development
Kenyon Industries, Inc.
Kenyon, Rhode Island 02836
IV-D-19 Walter L. Conine
John Boyle and Company
Salisbury Road
Post Office Box 791
Statesville, North Carolina 28677
IV-D-20 Paul B. Stelzner
Senior Vice President and C.0.0.
American Recreation Products
1224 Fern Ridge Parkway
St. Louis, Missouri 63141
IV-D-21 Guy A. Bivins
Manager, Plant Engineering
The Bibb Company
Post Office Box 4207
Macon, Georgia 31208
~~(continued)
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TABLE 2-1. (continued)
Docket
Item No»a Commenter/affiliation
IV-D-22 Wayne Holden
Technical Director
WestPoint Pepperell
Industrial Fabrics Division
Post Office Box 279
Pulaski, Virginia 24301
IV-D-23 Thomas Tantillo
Granitevilie Company
Graniteville, South Carolina 29829
IV-D-24 George E. Moseley
Secretary and General Counsel
Reeves Brothers, Inc.
Post Office Box 1898
Spartanburg, South Carolina 29304
aThe docket number for this project is A-83-42. Dockets are on file at
EPA Headquarters in Washington, D.C., and at the Office of Air Quality
Planning and Standards in Durham, North Carolina.
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1. Selection of the Source Category;
2. Affected Facility;
3. Selection of BOT and Emission Limits;
4. Control Costs;
5. Environmental Impacts;
6. Economic Impacts;
7. Compliance;
8. Test Methods and Monitoring;
9. Reporting and Recordkeeping;
10. Wording of the Regulation; and
11. Modification/Reconstruction.
2.1 SELECTION OF THE SOURCE CATEGORY
2.1.1 Applicability to the Leather Industry
Comment; One commenter (IV-D-2) wrote concerning the applicability
of the proposed standards to leather finishing. For certain products, a
thin polymeric coating is applied to the unfinished leather substrate.
Some coatings are applied'in organic solvent solution, although the use of
water-based emulsions is increasing. References ta leather as a substrate
found in the proposal preamble and in the proposed definition of web
coating seem to suggest that leather finishing operations would be covered
by the proposed rule. The commenter concluded that this would be improper
for the following reasons.
1. Leather finishing does not meet the applications criteria
established in the proposed standards. Leather is not handled as a
continuous web or substrate that is unrolled, finished, dried, and
rerolled. Rather, leather finishing is done on discrete skins, hides, or
sides. Also, most solvent-borne finishes are sprayed on the leather
rather than applied by seasoning machine or roll coater.
2. The leather-like materials that can be coated in continuous form
(bonded leather fiber products and artificial leathers) are not properly
or legally referred to as "leather" according to accepted trade practice
(American Society for Testing and Materials [ASTM] Method D1517) and
Federal Trade Commission guidelines. Therefore, these man-made substrates
should not be referred to as leather in the final standards.
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3. Leather Tanning and Finishing (Standard Industrial Classification
[SIC] 3111) is not among the eight SIC codes listed in the Volume I BID as
potentially affected by the proposed standards.
4. Consultation with a representative of the Emission Standards
Division (ESD) of EPA's Office of Air Quality Planning and Standards
confirmed that leather finishing was not intended to fall within the scope
of the proposed rule.
In view of these points, the commenter requested that all references
to "leather" be deleted in the final rule to avoid confusion.
Response; The commenter correctly noted that, as proposed, the
standards could be interpreted to apply to leather finishing operations.
The EPA concurs that leather, when defined as a "general term for hide or
skin . . ." (Annual Book of ASTM Standards), is not a continuous
substrate, and leather finishing was not intended to be covered under the
standards. Therefore, leather finishing has been excluded from the list
of web coating operations in the final standards. Leather-like materials,
such as urethane-coated and bonded leather fiber products are, however,
covered by the standards.
It should be noted that the exclusion of the "Leather Tanning and
Finishing" SIC code (SIC 3111) from the list of affected SIC's is not
grounds for exclusion from the standards. This list was intended to be
representative of potentially affected operations, not to be an inclusive
list.
2.1.2 Applicability to the Graphic Arts Industry
Comment; One commenter (IV-D-6) wrote that the proposed standards
could be erroneously construed to apply to the graphic arts industry. The
commenter stated that no facility in the graphic arts industry was studied
during the development of the proposed NSPS and that the Volume I BID
clearly excludes the* graphic arts industry. Furthermore, the commenter
met with a representative of the Chemicals and Petroleum Branch of ESD who
confirmed that EPA did not intend for this regulation to apply to the
graphic arts industry. The commenter recommended that the exclusion of
the graphic arts industry also be clearly stated in the preamble to the
final regulations.
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Response; The polymeric coating NSPS is not intended to include a
web coating category already subject to new source performance stan-
dards. As the commenter points out, the Volume I BID states that
polymeric coating of supporting substrates excludes "those operations that
print an image on the surface of the substrate." This exclusion also was
included in the proposal Preamble, Section IV.A.2. Exclusions.
Section 60.740(a)(3) has been added to the final standards to make this
exclusion clear. This section excludes "web coating operations that print
an image on the surface of the substrate or coating applied on the same
printing line that applies the image."
2.1.3 Applicability to the Paper Coating Industry
Comment; Two commenters (IV-D-9, IV-D-10) believed that the
exclusion of paper coating is unclear. One commenter (IV-D-9) stated that
the confusion results from the definition of "polymeric coating of sup-
porting substrates," which states "... a supporting web other than
paper," and from the lack of a definition for paper. The commenter
suggested the exclusion of "paper, paperboard, plastic film, metallic
foil, and metal coil" be stated in the "polymeric coating of supporting
substrates" definition. The commenter stated that if this suggestion were
followed, the definition of "paper coating" could be deleted, and that if
the suggestion were not followed, "paper coating" should be changed to
"paper" or "paper web."
The second commenter (IV-D-10) was concerned specifically with the
plastic film coating industry. This commenter concluded that the proposed
standards exclude coating on plastic film because; (1) the process is
considered a segment of the paper coating industry (which is excluded from
the proposed standards); (2) plastic film coating, to date, has been
regulated by the States under paper coating State implementation plan
(SIP) regulations; (3) the SIC code for this process (2671) was not
included in the list of potentially affected SIC codes; (4) the customers
who subsequently print or laminate the commenter's product are not
covered; and (5) the scope of the background study did not include plastic
film coating operations. The commenter stated that the plastic film
industry is different from the industries surveyed with respect to the
scale and type of equipment and the process itself.
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Also, the commenter (IV-D-10) stated that because the BID did not
survey the plastic film industry, several assumptions or conclusions
presented in the proposal preamble are invalid when applied to this
industry. According to the commenter, (1) statements in the proposed rule
concerning low-solvent coatings are not valid when applied to low-solvent
plastic film coating operations using large-scale equipment; (2) the
proposed NSPS implies that line speed and width increases are impractical;
however, this is untrue in the commenter's experience; (3) the incremental
cost of further reduction of the commenter's low-solvent coating formula-
tion emissions would be unreasonable; and (4) low-solvent waterborne
coatings should be 8DT for the plastic film industry regardless of the
volume of coating used.
If, in fact, plastic film coating operations are included under the
proposed regulations, the commenter requested that EPA:
1. Reopen the comment period for more detailed comments;
2. Revise the BID to include plastic film coating operations; and
3. Rescind the proposed NSPS until background Information for the
plastic film coating Industry is developed and evaluated.
Response; The proposed NSPS is intended to exclude paper coating
operations, which are defined in the proposed regulation as "the coating
of paper, plastic film, or metallic foil. . . ." These paper coating
operations are part of the industrial surface coating source category for
paper and were not Investigated during development of the standards for
polymeric coating of supporting substrates. The definition of polymeric
coating has been revised to clarify this point, and the definition of
paper coating has been deleted.
It should be noted that the exclusion of an industry segment from the
11st of affected SIC's does not mean the industry segment is excluded from
the standard. Such lists are not to be inclusive, but are intended to be
representative of potentially affected operations. Also, the fact that
subsequent processors of a coated product are not subject to the standards
does not, as suggested by one commenter, have any bearing on the applic-
ability of the standards to the initial coating process.
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2.1.4 Applicability to the Textile Coating Industry
Comment: Several commenters (IV-D-15, IV-D-18, IV-D-19, IV-D-20,
IV-D-21, IV-D-22, IV-D-23, and IV-D-24) requested that EPA establish a
separate subcategory in the standards for textile coating operations. The
commenters cited product and operational variability as factors limiting
this industry's ability to comply with the proposed standards.
Response; The EPA has carefully reviewed the technical comments
provided by ATMI and others. The specific comments and EPA's responses to
them are detailed elsewhere in this document (primarily in
Sections 2.3.1.1 and 2.3.1.3). As a result of this analysis, EPA has
decided not to create a separate subcategory or standard for the textile
coating industry. However, EPA has adjusted the overall level of the
coating operation standard downward to 90 percent in response to the
concerns raised by commenters. The EPA believes that this level of
control is universally achievable by the polymeric coating industry,
including textile coaters.
2.2 AFFECTED FACILITY
Comment; One commenter (IV-D-8) indicated that EPA should clarify
how the determination of the affected facility is to be made for coating
operations that share mix equipment. The commenter stated that this
situation, which is typical of the commenter's plants, is not adequately
addressed under the modification/reconstruction provisions. The commenter
presented a scenario that involved the installation of a new coating
operation served by an existing central mix room. The commenter was
concerned that existing coating operations served by the common mix equip-
ment would become affected facilities also.
Response; The affected facility is defined as "each coating
operation and any onsite coating mix preparation equipment used to prepare
coating for the coating operation." In the case presented by the com-
menter, the existing coating operations would not become subject to the
standards because they are not part of the affected facility that includes
the new coating operation. However, the existing mix equipment that
serves the new coating operation would become subject to the standards.
The only way that an existing coating operation would come under the
standards would be if the potentially affected facility of which it is a
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part (i.e., the coating operation with associated mix equipment) were to
be modified or reconstructed. A modification is defined in the General
Provisions (40 CFR 60.14) as ". . . any physical or operational change to
an existing facility which results in an increase in the emission rate to
the atmosphere of any pollutant to which a standard applies . . . ."
Certain exceptions are made, including the following: routine main-
tenance, repair, and replacement; an increase in production rate
accomplished without a capital expenditure; an increase in the hours of
operation; use of an alternative fuel or raw material if the existing
facility was originally designed to accommodate it; addition or replace-
ment of emission control equipment (as long as emissions are not
increased); and relocation or change of ownership. The General Provisions
(40 CFR 60.15) define reconstruction as the replacement of components of
an existing facility to the extent that the fixed capital cost of the new
components is greater than 50 percent of the fixed capital cost of a
comparable entirely new facility and that compliance with the standard is
technically and economically feasible. An increase in the emission rate
* *
need not occur.
Comment; Commenters noted (Docket Item IV-E-21) that it is not
always possible to dedicate a limited number of pieces of mix equipment to
a given affected coating line. The commenters were concerned that entire
mix rooms would become affected if a new coating operation is added.
Response; The commenters have interpreted the proposed regulation
correctly. However, EPA has revised the regulation to reduce the burden
on plants subject to the mix equipment standards. In most cases, venting
mix equipment emissions to a control device is judged to be cost effective
whether one piece or an entire mix room becomes affected. When a new
coating operation is constructed, a new control device would be necessary
to control its emissions. This control device could readily be designed
to accommodate emissions from the associated mix equipment that becomes
affected when the coating operation is constructed. Under this scenario,
the venting of mix equipment emissions to a control device is cost
effective.1
The hypothetical scenario of concern is that mix equipment could
become affected by the standards through modification or reconstruction of
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a coating operation that uses an existing control device. Although it is
considered unlikely, it is possible that the existing control device would
have insufficient capacity in reserve to handle all or part of the mix
equipment emissions.1 This would result in a requirement to install a
separate control device for these emissions; such separate control of mix
equipment emissions is not cost effective. Because it is possible that
mix equipment at some modified or reconstructed facilities could not be
controlled by existing control devices, the standards have been revised to
require use of covers alone (requirements discussed in response to
Comment 2.3.2.1) if a coating operation is modified or reconstructed
without concurrent construction of a control device. Concurrent construc-
tion is defined in the final regulation as the period of time in which
construction of an emission control device serving an affected facility is
commenced or completed, beginning 6 months prior to the date that
construction of the affected facility commences and ending 2 years after
the date that construction of the affected facility is completed. This
period is designated.because it is consistent with the normal planning and
purchase cycles for equipment of this type. The 2-year period also
coincides with the period for which records required under these standards
must be retained.
With this change to the standards, EPA considered whether the
affected facility definition should be changed from a combined defini-
tion. However, because growth in this industry is still expected to occur
in the form of new lines, the maximum emission reduction will be achieved
by retaining a combined affected facility definition (see proposal
preamble [52 FR 15916] for more discussion of the criteria applicable to
affected facility decisions).
2.3 SELECTION OF BDT AND EMISSION LIMITS
2.3.1 Control of Coating Operation
2.3.1.1 BDT and the Level of the Standard.
Comment; Seven commenters (IV-0-1, IV-D-7, IV-D-8, IV-0-11, IV-D-15,
IV-0-16, IV-D-17, and IV-0-18) questioned the capture, control device,
and/or overall efficiency required to comply with the proposed 93 percent
VOC emission reduction for coating operations. One commenter (IV-D-1)
said that the accessibility and clearances needed for feeding and
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retrieving products from a treater, the practicality of capturing
virtually 100 percent of vapors at all times, the reliability of
continuous monitoring equipment, and the number of different combinations
of substrates and coating solutions make compliance extremely doubtful.
The commenter suggested that, with diligent attention to the equipment, a
control device efficiency of 95 percent and a capture efficiency of
80 percent could be attained, allowing an overall efficiency of 76 percent
to be attained.
A commenter (IV-D-8) stated that 93 percent overall efficiency has
not been demonstrated for a polymeric coating operation. Specifically,
the commenter stated that the capture efficiency of 98 percent that would
be required to obtain the overall efficiency of 93 percent has not been
demonstrated relative to the design factors assumed in the economic
analysis. Also, the commenter stated that the selection of a carbon
adsorber efficiency of 95 percent is based on insufficient data from the
polymeric coating industry. The 95 percent efficiency was based on test
data that included only one polymeric coating operation. According to the
commenter, these data cannot adequately demonstrate a control technology
for an entire industry that uses a multitude of solvents and coating
formulations. The commenter stated that EPA has failed to demonstrate
that a 95 percent efficiency is consistently achievable and that EPA needs
to review carbon adsorption data for the various solvents typically used
in the polymeric coating industry before concluding that such an effi-
ciency is consistently attainable. Another commenter (IV-D-11) stated
that, based on their best information, the overall efficiencies specified
in the regulation could not be consistently attained for new lines, except
for those that use low-solvent coatings.
Two commenters (IV-D-7, IV-D-15) cited batch operations, the use of
multiple solvents, and the need for frequent (to continuous) worker access
to the coating application/flashoff area as reasons for not being able to
comply with the proposed standards. In the first correspondence (IV-D-7),
only the 95 percent efficiency ascribed by EPA to carbon adsorption was
addressed. The commenter indicated that the data from a polymeric coating
plant, which are from a plant using a single solvent, do not adequately
reflect coating operations that use multiple solvents, other solvents, or
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multiple substrates and coating head configurations. The commenter said
that the solvent recovery efficiencies are biased because they rely on
data obtained with gas analyzers only under the most favorable short-term
operating conditions,, The second correspondence (IV-D-15) also addressed
the concern that a total enclosure that would meet the required capture
efficiency while maintaining worker access could not be designed. Case
studies from five plants were presented as documentation of these claims
(IV-D-15).
Response; The EPA has determined that the final standards for
coating operations are attainable. The following discussion of support
for this conclusion addresses: (1) capture efficiency, (2) control device
efficiency, (3) overall control efficiency, and (4) VOC recovery. For the
response to the comment about the reliability of continuous monitoring
equipment, see Section 2.8.3.
1. Capture efficiency. In response to comments, EPA has reevaluated
the feasibility of total enclosures 1n the polymeric coating industry.
The term "total enclosure" means a structure that is constructed around a
source of emissions and operated so that all VOC emissions are collected
and exhausted through a stack or duct. With a total enclosure, there will
be no fugitive emissions, only stack emissions. The drying oven itself
may be part of the total enclosure. A total enclosure must satisfy all of
the design and operational requirements as defined in the promulgated
regulation and summarized in Table 2-2. Alternatively, it must be
demonstrated, to the Administrator's satisfaction, to be equivalent to
these requirements. To evaluate the comments, Section 114 Information
requests were sent to three facilities that had indicated that enclosures
were in use, and plant visits were made to three facilities that had
indicated that they were batch operations and needed frequent access to
the coating equipment during operation. An expert in industrial
ventilation and a vendor of local ventilation systems were contacted.
Using the data gathered and standard ventilation principles and
guidelines, EPA reached the conclusions discussed below.2
As indicated by the commenters, a small total enclosure immediately
around the applicatlon/flashoff area is not feasible at facilities where
frequent, routine access to the coating equipment is required. At such
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TABLE 2-2. SUMMARY OF TOTAL ENCLOSURE CRITERIA
Definition; "Total enclosure" means a structure that Is constructed
around a source of emissions so that all VOC emissions are collected
and exhausted through a stack or duct to a control device. With a
total enclosure, there will be no fugitive emissions, only stack
emissions. The drying oven itself may be part of the total enclosure.
Design and operational criteria;
1. The only openings in the enclosure shall be forced makeup air and
exhaust ducts and natural draft openings such as those through which
raw materials enter and exit the coating operation.
2. The total area of all natural draft openings shall not exceed
5 percent of the total surface area of the total enclosure's walls,
floor, and ceiling.
3. All access doors and windows shall be closed during normal operation
of the enclosed coating operation, except for brief, occasional
openings to accommodate process equipment adjustments. If such
openings are frequent, or if the access door or window remains open
for a significant amount of time during the process operation, it must
be considered a natural draft opening. Access doors used routinely by
workers to enter and exit the enclosed area shall be equipped with
automatic closure devices.
4. Average inward face velocity (FV) across all natural draft openings is
a minimum of 3,600 meters per hour (200 feet per minute) and
demonstrably inward at all times.
5. All sources of emissions within the enclosure shall be a minimum of
four equivalent diameters away from each natural draft opening.
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facilities, it is doubtful that the access ports necessary to reach the
equipment will conform with the total enclosure specification for separa-
tion between sources of VOC and openings in the enclosure. Nevertheless,
even at facilities with extensive access requirements, local ventilation
systems can be constructed that will achieve a very high capture effi-
ciency while affording necessary access. The most universally applicable
approach consists of substantially enclosing the application/flashoff area
while providing ports that can be opened when access is needed. With a
well-designed system, capture will be sufficient to maintain the VOC
concentration below the threshold limit value (TLV) outside the enclosure,
protecting the health of the workers in the area. The airflow necessary
in a well-designed system will be reduced to the point that the total
volume can be used as makeup air in the drying oven, minimizing control
costs.
In most cases, the local ventilation system described above could be
used in conjunction with a larger enclosure to meet the specifications for
a total enclosure. The total enclosure could consist of the drying oven
itself coupled with a small room (large enough for workers) constructed
around the application/flashoff area, a small room constructed around the
entire coating operation, or even a large coating room with several
coating operations. The size of the total enclosure is immaterial as long
as the specifications are met.
Despite the range of acceptable total enclosure configurations, there
remains the possibility that some facilities may not be able to install an
enclosure that meets the specifications. For instance, at an existing
facility adding a new coating operation or modifying/reconstructing an
existing coating operation, space constraints might not allow construction
of any enclosure large enough for personnel to work within during
operation. If the same facility could not install a small total enclosure
immediately around the application/flashoff area because of access
requirements, the use of a total enclosure would not be feasible for that
facility. One of the facilities visited during the investigation of this
issue would probably encounter these constraints.
Because there may be facilities at which a total enclosure is not
feasible, EPA investigated capture systems that fell short of the
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requirements for a total enclosure. Based on EPA's analysis, a capture
efficiency of 95 percent can readily be achieved without a total enclosure
through the use of a well-designed local ventilation system. Although the
actual percentage varies from facility to facility, about 90 percent of
the VOC emissions from a coating operation are generated within the drying
oven. Assuming that all these emissions are captured, as they will be in
a well-designed oven operating under a slight negative pressure, only
50 percent of the emissions generated in the application/flashoff area
must be captured to achieve a total capture efficiency of 95 percent.
Even if only 80 percent of VOC emissions from the coating operation are
generated in the drying oven, only 75 percent of the application/flashoff
area emissions must be captured to achieve 95 percent overall capture.
The EPA has concluded that these capture efficiencies can be achieved in a
cost-effective manner with a well-designed local ventilation system.
2. Control device efficiency. Carbon adsorption has been used for
the last 50 years by many industries to recover a wide variety of
solvents. With the experience gained from extensive application under
very diverse conditions, the technology has matured to the point that an
adequately designed, operated, and maintained system can readily attain an
efficiency of 95 percent or higher on a continuous basis. This fact has
been demonstrated across many industries with many different solvents and
solvent blends. The efficiency of a carbon adsorption system is
determined by its design and operating parameters and the composition of
the solvent-laden airstream (SLA) vented to it, not by the process
equipment that generates the exhaust stream.3 Thus, it is reasonable to
expect the attainment of similar efficiencies through the application of
this technology in the polymeric coating Industry.
The efficiency of carbon adsorption in this and related web coating
industries was discussed in the Volume I BID. Measurements during tests
ranging from a short-term gaseous emissions test to a 78-hour material
balance Indicated adsorber efficiencies of 97 percent or higher. At a
pressure sensitive tapes and labels (PSTL) plant, an overall control
efficiency of 93 percent was achieved over a 4-week period. The fact that
this plant, which coated a number of products using a wide variety of
solvents, attained a control level of 93 percent demonstrates that a
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carbon adsorption system is capable of operating at an efficiency high
enough to meet the standards. As discussed in the next comment, data
received from a polymeric coating plant also support control efficiencies
capable of meeting the standards.
The EPA has recently concluded an extensive study of the ability of
carbon adsorbers to operate continuously at least 95 percent efficiency.
Thts report addresses many of the problems cited by commenters that could
be faced by a batch operator. In particular, there are two major ways
that batch operations could affect carbon adsorber performance."* One
effect would be expected to occur where multiple lines are ducted to a
carbon adsorption system. Under this scenario, it is possible that as
lines are brought off- and on-line, the resulting variable flowrates and
VOC concentrations of the SLA ducted to the control device could adversely
affect recovery efficiency. A second effect would be evident in a
situation where an SLA contains varying blends of solvents. If this
variable stream is ducted to a single control system, the result could be
decreased recovery efficiency.
The effect of variable flowrates should not be a problem with a
properly designed system. The primary effect of an increase in volumetric
flowrate is to change the width of the mass transfer zone within the
carbon bed. As the superficial velocity increases as a result of a higher
flowrate, the width of the mass transfer zone also increases because the
individual carbon pellets are exposed to the adsorbate for a shorter
period of time. With a wider mass transfer zone, the length of the
adsorption cycle prior to breakthrough will decrease. However, a bed
should be designed for worst-case flowrate conditions (the maximum
flowrate expected to be ducted to the system at a given time), so there
should be no periods of operation when breakthrough occurs before there is
sufficient time to have regenerated a fresh bed.1*
Another question related to flowrate is the effect of short-term
variations in flowrate on system efficiency. One report presents data
from a case where the flowrate varied randomly during the entire
adsorption cycle and ranged from 25,000 to 45,000 scfm. The recovery
efficiencies during this time period varied less than 0.5 percent with all
efficiencies being well above 99 percent.1* Therefore, short-term
variations in flowrate do not appear to be a problem.
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The remaining concern with respect to variable flowrates is whether
they could result in an increase in outlet concentration (rather than a
decrease in cycle length as discussed above). However, increases in
outlet concentration are due either to the inlet stream physically by-
passing a portion of the bed (through channeling, for example) or to a
buildup of heel in the last few inches of the bed. Neither of these
situations is expected to occur as a result of variations in the
flowrate.
The effect of variable VOC concentrations in the SLA on carbon
adsorber performance is also expected to be insignificant. Increasing the
concentration in the SLA increases the working capacity of the carbon, but
not to such an extent that the increase in mass loading is offset. The
result is that breakthrough occurs sooner. Over the long term, this could
affect the performance of the system if capacity is exceeded, but in a
well-designed system this should not occur.1*
The short-term effect of concern is whether variations in inlet
concentration affect; outlet concentration. The outlet concentration is a
function of the amount of heel that remains in the last few inches of the
bed after regeneration. Because the inlet stream reaches equilibrium with
the carbon within the mass transfer zone, the amount of heel at the
adsorber outlet is independent of inlet concentration.1* Thus, inlet
variations would not be expected to affect outlet concentration.
The carbon adsorption report presents test data from two performance
tests that verify this relationship. In the first case, inlet concentra-
tions ranged from 200 to 550 ppm while the outlet concentration varied
only from 5 to 15 ppm; the corresponding removal efficiency varied from 95
to 99 percent. In the second case, the inlet concentrations varied from
40 to 880 ppm while the outlet concentration remained relatively constant
(0 to 5 ppm). During the majority of the test period the removal effi-
ciency was well above 95 percent. However, when the inlet concentration
dropped below 50 ppm, the removal efficiency was also reduced to less than
95 percent. This was expected because properly designed and operated
carbon adsorbers are essentially constant outlet concentration devices, so
a very low inlet concentration for an extended period will reduce short-
term efficiency.1*
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The presence of low inlet concentrations or minor variations in
outlet concentrations should not pose a major problem for a facility
attempting to show compliance with the coating operation standard.
Performance test and monitoring data are averaged over adsorber system
cycles, so short-term inlet variations will not greatly affect the long-
term average. For the facility referenced above as having inlet
concentrations below 50 ppm, the data were reanalyzed using the averaging
periods that would apply under the polymeric coating regulation. The
results of this analysis show that the average efficiency is greater than
95 percent, and the facility would not generate excess emissions. Under
similar inlet concentration conditions, a carbon adsorber at a polymeric
coating plant should exhibit similar efficiencies. It is unlikely that
more extended periods of low inlet concentrations would occur at polymeric
coating plants. The standard has been revised to preclude periods of
startup and shutdown for purposes of the gas-phase test to prevent the
possibility that extended periods of startup and shutdown would bias test
results. (Liquid-phase testing is not as sensitive to this potential bias
because periods of startup and shutdown represent only a fraction of the
overall test period of 3 to 30 days.) This change is consistent with the
General Provisions (40 CFR 60.8(c)).1*
The carbon adsorption report notes that, because the outlet
concentration remains relatively constant throughout an adsorption cycle,
large variations in the inlet concentration will result in corresponding
variations 1n removal efficiency. However, if the bed is properly
designed and regenerated, a constant outlet concentration can be attained
such that greater than 95 percent removal is achieved for the entire range
of inlet concentrations. Furthermore, by diverting or shutting off the
airflow from Idle equipment, inlet concentrations can be consistently
maintained at higher levels to ensure the desired removal efficiency.1*
Variations in the solvent blend and VOC 1n the SLA ducted to a carbon
adsorber can affect either adsorption time or desorption steaming require-
ments. If this is not accounted for, particularly if timers are used to
trigger bed changeover, recovery efficiency could decline. The effects of
variable solvent blends are discussed further in Section 4 below.
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It is true that fixed-bed carbon adsorbers are not suited to every
VOC control application. In such cases, either a fluidized-bed carbon
adsorber or a condenser can be used. The analysis of costs carried out
prior to proposal and presented in the Volume I BID indicated that a
condenser would be less costly to purchase and operate than a carbon
adsorption system. Incinerators may also be cost effective in some
control situations.5
3. Overall control efficiency. An overall control efficiency of
93 percent has been demonstrated by a 4-week liquid material balance at a
plant in the PSTL industry that is equipped with a "total building air
evacuation system," which was assumed to be a total enclosure for purposes
of proposal analyses. The performance of this PSTL plant is considered
representative of the control efficiency attainable in the polymeric
coating industry because of the many similarities in the two industries.
In both, coatings with a similar range of solvent contents are applied
with the same types of applicators to continuous substrates and dried in
the same types of drying ovens. Capture and control systems for emissions
of VOC are very similar. The production at the PSTL plant during the test
period was characterized by many short runs of many different products
using a variety of solvents, as is often the case at polymeric coating
plants.
Since proposal of the polymeric coating standards, EPA received
liquid material balance data from a member of the industry (Grace) who
coats textile printing blankets (IV-0-16). This operation consists of two
coating lines in a room-type enclosure (the data presented by the
commenter [IV-D-16] are presented in detail in the section on
Comment 2.3.1.). The EPA concluded that these data, which show 93 percent
overall recovery based on a 3-day liquid material balance, substantiate,
along with the PSTL data, that emission capture and reduction systems are
capable of achieving 93 percent control.
The EPA, however, has reevaluated the proposed standards in light of
industry comments (particularly issues related to batch operations and
design and use of total enclosures discussed elsewhere in this response
and in Section 2.3.1.3). Although the polymeric coating standards
require demonstration of an overall level of control, the BDT for the
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standards is discussed typically in terms of the efficiency of capture and
control device efficiencies. The product of these efficiencies yields the
overall level of control. The control device component of BDT has been
demonstrated to be a minimum efficiency of 95 percent for this industry
(see Section 2 on control device efficiency for more discussion of this
issue). Therefore, the important variable in evaluating the overall level
of control that can be achieved by BDT is the efficiency associated with
capture component.
Any change in the assumed level of capture efficiency should be
evaluated considering that (1) the two data points at 93 percent overall
efficiency (PSTL and Grace) are associated with unknown capture and
control device efficiencies and (2) neither capture system demonstrated
complete consistency with EPA's total enclosure criteria. It is quite
possible (and perhaps probable) that capture efficiency at these plants
was less than the 98 percent minimum previously ascribed to a total
enclosure. Therefore, to conclude that capture efficiency was 98 percent,
based on an assumed control device efficiency of 95 percent (i.e.,
0.98 capture x 0.95 control = 0.93 overall control efficiency) may be
oversimplification. A more conservative means to estimate the capture
efficiency of these two facilities is to assume that the control device
efficiency was higher (i.e., 98 percent) instead of the minimum
95 percent. If so, the 93 percent overall control could have resulted
with only a 95 percent efficient capture device.
To ensure the selection of achievable standards for the entire
industry, the overall level of control required should be based on the
minimum efficiencies of the two components of BOT. The EPA has concluded
that control devices are at least 95 percent efficient, even while
acknowledging that they are capable of, and often achieve, much higher
efficiencies. Although EPA believes that total enclosures achieve
essentially 100 percent or total capture, it has not been adequately
demonstrated that all segments of this diverse industry can install and
operate total enclosures that meet EPA's specifications (see Section 1 on
capture efficiency for more information on this topic). It is, therefore,
reasonable to allow for this variability when setting the capture system
efficiency component of BDT for this industry. Based on these
2-22
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considerations, EPA has adjusted the standards downward from 93 percent to
90 percent overall control (i.e., 0.95 capture x 0.95 control =
0.90 overall control efficiency). The promulgated standards recognize
that strict adherence to EPA's total enclosure criteria may be neither
universally achievable nor required to meet the standards but would still
allow use of the alternative standard for those sources that can meet the
total enclosure specifications. The EPA believes that this will be an
attractive alternative for that majority of plants for which a total
enclosure is feasible. Because the compliance test provisions associated
with a total enclosure are simpler and less expensive to carry out than a
capture efficiency test, there is continuing incentive for sources to
install total enclosures.
It should also be noted that there is flexibility in the emission
reduction standard. Because only the overall emission reduction is
specified, sources may vary capture and control efficiencies as they wish
as long as the required overall emission reduction of 90 percent is
maintained. Thus, a source may choose to operate the control device in
excess of 95 percent efficiency and maintain a capture efficiency below
95 percent, or vice versa.
In conclusion, the standards have been established at an overall
control level of 90 percent, with BDT defined as a 90 percent efficient
emission reduction system that is composed of an emission capture system
and control device. The option of using a total enclosure as the emission
capture system is allowed where feasible and is attractive to the source
because it simplifies the performance test. This change to the standards
takes into account concerns about variability in measurement technique,
operating parameters, worker access requirements, etc. As Table 2-3
shows, the revised standards (represented by Regulatory Alternative IIA)
remain cost effective despite a lower emission reduction. This option
potentially results in a projected decrease in nationwide VOC reduction
over 5 years compared to the standards as proposed (964 Mg [1,062 tons]
compared to 1,060 Mg [1,168 tons]). However, because of the use of total
enclosures or control devices that achieve more than 95 percent
efficiency, in many cases, facilities will actually achieve emission
reductions much greater than 90 percent.
2-23
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2-24
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4. VOC recovery. The type of solvent used and VOC generated is a
key design criterion in any carbon adsorption system. The adsorption
characteristics of each compound are assessed using data on their physical
properties, and the system is designed to accommodate these properties.
While adsorbers can be designed to recover a blend of solvents and other
VOC successfully, changes in the characteristics of a feed stream (i.e.,
the introduction of varying solvent blends due to a batch process and cure
volatiles) can affect both adsorption and desorption cycles.** If the
system cannot accommodate the new SLA stream, it is possible that the
working capacity of the bed could decrease below design conditions or that
costs of increased steam requirements or carbon bed replacement due to
excessive fouling could lead to poor performance or excessive costs of
operation.
The operator's responsibilities under these conditions are to design
the system to accommodate worst-case VOC composition conditions and to
monitor the adsorber outlet streams adequately to assure that the beds are
not operated after breakthrough. It is advantageous to standardize
*
solvent blends and minimize the number of "incompatible" solvents likely
to be ducted to the control device simultaneously. There may be cases
where these measures are impossible and carbon adsorber performance cannot
be continuously maintained at 95 percent efficiency at reasonable cost; in
these cases, carbon adsorption is not the appropriate control tech-
nology. Incineration is often selected because it can control a wide
variety of VOC with relative ease.
A preliminary cost analysis shows that, when compared to baseline
control assuming use of an incinerator, a 98 percent efficient incinerator
can cost-effectively control emissions from a coating operation equipped
with a total enclosure. Incinerators were not considered cost effective
at proposal because they were considered a more stringent regulatory
alternative, and the incremental cost compared to a carbon adsorber at
93 percent overall control was considered unreasonable. However, if
conditions at a new or modified line prohibit the use of carbon adsorp-
tion, these same conditions would prohibit the use of carbon adsorption
under baseline regulations. In fact, 67 percent of the VOC emission
control devices used by the industry at the time of proposal were
2-25
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Incinerators. Therefore, the cost of incineration under the NSPS should
more logically be compared to the cost of incineration under baseline
regulations. The cost effectiveness of control is reasonable in all cases
when analyzed using these assumptions.5
Even if the use of multiple solvents does not affect carbon adsorber
performance, it is possible that the cost of VOC recovery may be adversely
affected. The model plant analysis did include the cost of simple
distillation (one water-soluble solvent and one blend of two solvents),
but allowed a 100 percent credit for the recovered solvent. It is
possible that, in the case of multiple solvents that are difficult and
expensive to distill or where stringent solvent purity requirements exist,
a 100 percent credit may overstate the actual credit available to some
facilities. An analysis of the regulatory alternatives developed at
proposal (RA's I, II, and III) and of an alternative developed post-
proposal (RA IIA) shows that solvent credits less than 100 percent (i.e.,
60, 30, and 0) result in reasonable control costs in the majority of
cases. Reduced solvent recovery credits are not cost effective for some
lines, particularly small lines.5 However, these lines would likely have
the same problem at baseline conditions, and incineration would be the
control device of choice. Therefore, commenters are correct that VOC
recovery could be precluded under some conditions, but this is not the
result of the NSPS.
Comment; A commenter (IV-D-16) presented data that, according to the
commenter, indicated that only under ideal conditions could the plant
(Grace) recover 93 percent of the VOC applied at the coating operation and
that, on a day-to-day basis, recovering 93 percent is very unlikely. (The
data are claimed to be confidential business information and, therefore,
are not presented here.) The commenter stated that their equipment is the
same as Regulatory Alternative III. The commenter uses a knife-over-roll
coater with a substantially enclosed coater. The coating operation
(including the substantially enclosed coater) is enclosed in a room that
is under negative pressure. Exhaust from the room is sent to a carbon
adsorption system. Over a 3-day continuous run, the operation achieved
93 percent recovery based on a liquid-liquid material balance. The
average recovery efficiency over a month for this operation, also
2-26
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calculated using a liquid-liquid material balance, was 86 percent. The
commenter stated that even though 93 percent is theoretically possible,
85 percent is the maximum practical recovery rate.
Response; Followup contacts were made with the commenter to
determine the differences between the "ideal" conditions during the 3-day
run when a 93 percent overall efficiency was measured and the "typical"
operation during the remainder of the month when a monthly average of
86 percent was measured. The two major differences noted by that
commenter were (1) more careful measurement taken during the 3-day run and
(2) a shorter carbon bed adsorption time during the 3-day run. The com-
menter emphasized the extensive effort and extreme care used in obtaining
measurements for the 3-day material balance. The adsorption time was
decreased to 75 percent of the normal adsorption time during the 3-day run
to ensure that breakthrough would not occur. The commenter noted that
this reduction in adsorption cycle time was not cost effective because of
the increased steam requirements for desorption. However, the commenter
added that the difference in cycle time would probably not have a
significant effect on performance because the original cycle length is
"very conservative.1"7 The commenter stated that the plant would prefer to
use breakthrough monitors instead of timers to control
adsorption/desorption cycles; however, a reliable monitor has not been
found (IV-D-16).
Although it is not possible to determine quantitatively the cause of
the difference between the two data sets because separate control and
capture efficiency are not provided in either case, comparison of the
short-term and long-term performance data indicates that the measured
differences may largely be due to accounting for mix room losses, retained
VOC in the web, and waste VOC in the short-term calculations. These
losses were not taken into account in the monthly efficiency calcula-
tions. When the short-term efficiency is recalculated without accounting
for these losses, the value is consistent with the typical monthly
efficiencies reported by the source. Thus, it is reasonable to expect
that, if these types of losses were taken into account during the long-
term measurements, the measured overall efficiency would approximate the
short-term results. This indicates that short-term data may be reasonably
2-27
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representative of long-term performance if measured on the same basis.6
Furthermore, the short-term measurement techniques reflect the facility's
efficiency as it is to be determined for the purposes of conducting a
liquid material balance. Thus, EPA believes that rather than discredit
the level of the standard, these test data support the standard.
The information from the commenter does indicate that performing a
monthly material balance in some cases (i.e., when multiple coatings are
used) may require more resources than are reasonable to spend on
compliance demonstrations. However, alternative methods of demonstrating
compliance with the standards are available (see Section 2.7.2) such as the
alternative standard, gas-phase test, and short-term (3- to 7-day) liquid
material balance. In any case, the monthly liquid material balance
compliance provision has limited applicability and would not be an
appropriate compliance method for the situation described by the commenter
because multiple emission sources are ducted to the same control device.
Comment; One commenter (IV-0-17) stated that a major flaw in the
regulation is the lack of acknowledgment of the variability in any coating
process and in measuring its efficiency. The commenter stated that all
available data should be statistically analyzed and the control limit
based on, at a minimum, the average less three sigma. The commenter
pointed out that the results from this type of statistical analysis were
used in EPA's textile treated wastewater effluent regulations.
Response; The EPA has considered the range of variable operating
conditions likely to be found in this industry. Based on both the theory
and actual application of BDT, EPA has determined that these variable
operating conditions do not affect a facility's ability to meet an overall
control level of 90 percent, representative of BOT. For example, carbon
adsorption has been shown to achieve 95 percent efficiency on a continuous
basis despite the use of multiple solvents and multiple runs.** Enclosures
capable of achieving 95 percent or greater capture efficiency while
allowing safe worker access have been demonstrated.***6 Also, the PSTL
plant data that are used as the basis for determining the performance of
BDT resemble these operating conditions more closely than they resemble
cases of single solvents, long production runs, and limited worker access.
2-28
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The fact that statistical analysis has been used under other EPA
programs is not relevant to the NSPS program. Standards prepared under
this program are established under Section 111 of the Clean Air Act and
are required to reflect "the degree of emission limitation and the per-
centage reduction achievable through application of" best demonstrated
technology (BDT). The selection of BDT is to be based on:
. . . application of the best system of continuous
emission reduction which (taking into consideration the
cost of achieving such emission reduction, and nonair
quality health and environmental impacts and energy
requirements) the Administrator determines has been
adequately documented.
The selection of BDT from a range of alternatives is based on engineering
and cost evaluations of the technical feasibility and environmental and
cost impacts from application of the technology to the industries in the
source category. Once BOT is selected, it is assumed, by definition, to
apply uniformly to the source category. If a single BDT does not apply to
the entire source category, alternate BOT's may be designated for subcate-
gories. A statistical basis for the standard such as that suggested by
the commenter is not appropriate under the NSPS process described above.
2.3.1.2 Exemption Level.
Comment: A State agency (IV-D-9) recommended adding a requirement
for 90 percent control for facilities using less than 110 m3/yr
(29,059 gal/yr) (95 Mg/yr [105 tons/yr]) of VOC if the incremental cost
effectiveness is less than $l,100/Mg. The commenter stated that
(29,059 gal/yr) (95 Mg/yr [105 tons/yr]) of VOC and suggested evaluating
this option by using model operation(s) below 95 m3/yr (25,096 gal/yr)
(82 Mg/yr [91 tons/yr]) of VOC usage.
Response; With the development of Regulatory Alternative IIA and the
decision to reduce the overall level of control required by the standards
from 93 to 90 percent, EPA reevaluated the VOC use cutoff level for this
industry. This analysis focused on the same basic question as that raised
by the commenter, e.g., would cost-effective control be possible for
facilities that qualify for the lower cutoff level. As can be seen from
Table 2-3, cost effective control of such facilities at a 90 percent (or
2-29
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lower) overall control level (Regulatory Alternative IIA) is theoretically
possible. However, it is expected that the environmental impact of the
change would be relatively small. According to the economic impact
analysis conducted at proposal, it is expected that growth in this
industry will occur in lines with annual VOC usage greater than 110 m3/yr
(29,059 gal/yr) (95 Mg/yr [105 tons/yr]). Therefore, the promulgation of
a lower VOC use cutoff will not affect the costs and emission reductions
projected as a result of the NSPS and the cutoff level has been retained
as proposed. Furthermore, it is expected that most facilities will choose
to comply with the alternative standard, thus achieving at least 93
percent overall control. For these facilities, the analysis that
determined the proposed cutoff is still applicable. In any case, EPA will
reconsider the cutoff level at the 4-year review of the NSPS if additional
data indicate that there is an environmental benefit to use of a lower
cutoff.
2.3.1.3 Consideration of Variable Operating Conditions.
Comment; Ten commenters (IV-0-5, IV-D-7, IV-D-8, IV-0-12, IV-D-13,
IV-D-14, IV-D-15, IV-D-17, IV-0-18, IV-D-21) believed that EPA did not
properly consider the full range of practices in the industry in develop-
ment of the proposed standard. One of the commenters (IV-0-5) indicated
that the unique character of the printing blanket coating industry makes
total enclosure of the coating operation infeasible (see Section 2.4.1).
According to the commenter, EPA has failed to satisfy its statutory duty
to consider the range of relevant variables that may affect emissions in
different plants and promulgate achievable standards. Another commenter
(IV-D-8) stated that EPA needs to review a broader cross-section of the
fabric coating industry. Specifically, coating operations often have
traces of fine resin particulate matter entrained in the dryer exhaust
stream that would cause blinding of the carbon bed or catalytic incin-
erator. The issue of carbon bed contamination was also addressed by
another commenter (IV-D-12). This commenter stated that the carbon beds
would become contaminated by airborne plasticizers emitted during curing
processes and powders emitted during mixing.
Other commenters (IV-D-7, IV-D-13, IV-D-14, IV-D-15, IV-D-18,
IV-D-19, IV-D-20, IV-D-21, IV-D-22, IV-D-23, IV-D-24) believed that EPA's
2-30
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models do not adequately reflect the diversity in the polymeric coating
industry because the models are based on operations that use one solvent
on one substrate utilizing equipment dedicated to one method of coating.
However, according to the commenters, much of the coating equipment is
used with several solvents or solvent blends; substrates of several types,
thicknesses, and widths; and various impregnating and coating head
configurations. Also, because of the specialized properties of coated
fabrics, long, efficient runs are rare, and batch processing is typical.
One commenter (IV-D-13) stated that coating runs vary from 500 to
25,000 yards and that some days one coating formulation is run con-
tinuously, while other days as many as six different formulations may be
used. Another commenter (IV-D-14) presented production parameters that
may affect emission rates and that demonstrate the variety of substrates,
coatings, solvents, and manufacturing methods used. This commenter stated
that the coating processes use seven different solvents. A commenter
(IV-0-7) contended that models that base control efficiency only on size
and solvent use fail to consider adequately major differences in process
operations that affect both efficiencies and costs. One commenter
(IV-D-12) stated that a review of each plant should be made to determine
the final standard because of the diversity of formulated products in the
textile finishing market.
A commenter (IV-D-7) disagreed with the assumptions and models used
by EPA in developing the proposed standards. The commenter stated that
the characterization of magnetic tape coating operations as similar to the
polymeric coating industry is grossly inaccurate and jeopardizes the
validity and supportability of the proposed rule. Another commenter
(IV-D-13) also expressed concern about data transfer from an organic
solvent-based tape coating line because all polymeric coaters do not have
continuous production like the tape manufacturers.
A commenter (IV-0-7) indicated that EPA was in error in including a
model plant controlled by an air-atmosphere condensation system in its
analysis, while not considering the use of an inert-atmosphere condenser.
The commenter stated that no air-atmosphere condenser is in use in the
polymeric coating industry and that EPA has not demonstrated that one can
be designed to fit such operations. The commenter also stated that EPA
2-31
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was 1n error to assume the use of a VOC concentration of 25 percent of the
lower explosive limit (LEL) as the concentration in the oven exhaust and
the control device inlet stream. This assumption fails to account for the
lower concentrations found in air from solvent storage tanks, mixers, and
flashoff areas that would reduce the concentration in the inlet to the
control device, thus reducing efficiency. In addition, the commenter
stated that an oven cannot be safely operated at this VOC concentration.
According to the commenter, EPA has accepted the claims of vendors in this
matter, but has no factual data to support this contention.
Response; The EPA believes that the range of practices typical in
the polymeric coating industry have been adequately considered in the
development of the standards. Based on contacts with and visits to a
large number of polymeric coating plants over the course of standards
development, four different types of "model lines" were developed to
represent the diverse segments of the industry. To account for the range
of sizes typically found in each sector of the industry, the impacts of
the regulatory alternatives were analyzed for two or three annual VOC use
rates within each type of model facility. In all, a total of nine
different combinations of facility type and size were analyzed. In the
judgment of EPA, these model plants cover the range of variables that
affect VOC emissions, and these variables have been given proper
consideration in the development of the standards. In fact, after
proposal EPA visited and requested detailed process information from
representative plants in order to learn more about enclosure design and
capture efficiency parameters as well as batch operations. This
information confirmed the validity of EPA's approach.
The commenter that manufactures printing blankets (IV-0-5) has not
shown that the process used by his company cannot be controlled with
reasonable cost effectiveness. The EPA believes that cost-effective
control is feasible. A more detailed treatment of this issue is presented
in Section 2.4.1.
Difficulties with particulate matter in the SLA stream were not
raised as an issue by industry contacts during the background study.
However, they have been encountered in many applications of emission
control technology. Filters upstream of the VOC control device can
2-32
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generally alleviate the problem at low cost.8 In cases where participate
contamination is excessive or where the gas stream quickly deteriorates
the filters (assuming that there is no cost-effective, compatible filter
material), thermal incineration, rather than carbon adsorption or
catalytic incineration, may be the best control technique. In any case,
the source would encounter the same difficulties in the absence of the
NSPS under baseline control regulations, so the costs incurred cannot be
ascribed to the NSPS.
In response to the commenters who stated that EPA needs to review a
broader cross-section of the industry, EPA believes, as discussed above,
that the model line analysis carried out adequately considered the range
of practices in the industry. The model lines were developed based on
extensive contact with industry (including textile and other commission
coaters) in the form of plant visits, Section 114 information requests,
and telephone contacts. Because of the variability of the industry, plant
parameters were developed based on annual VOC consumption and basic
coating line configurations rather than product specific parameters. This
approach is feasible because control device efficiency depends on design
and operating parameters of the control device and the composition of the
SLA stream, not on the process or equipment that generates the exhaust
stream. Emission capture systems can be configured to achieve the
required capture efficiency without interfering with necessary process
operations.2 If the variations in VOC, substrates, coating heads, and run
lengths are properly considered during the design phase of the control and
capture systems and appropriate operation and maintenance procedures are
established and observed, process variations need not result in reduced
efficiency.
The EPA has determined that most coating operations can be totally
enclosed. The appropriate enclosure design may vary from a small struc-
ture fitting closely about the application/flashoff area to the entire
room in which the coating operation is located. Even in cases where
access requirements rule out a close-fitting total enclosure and space
constraints make a room-type enclosure impossible, a well-designed local
ventilation system can achieve adequate capture to meet the final
standards. Carbon adsorption, when designed for the worst-case
2-33
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conditions, can readily handle varied loading. (See Section 2.3.1.1 for
discussion of BDT and the level of the standard.) Two types of model
lines that were analyzed by EPA included distillation equipment for the
separation of blended or water-miscible solvents and were found to be cost
effective in meeting the standards. Thus, the use by some plants of
multiple solvents, substrates, and coating techniques does not render
invalid the analyses carried out by EPA.
The responses to the other points raised by commenter IV-0-7 are as
follows:
1. Although there are differences between magnetic tape and polymeric
coating lines, the general characterization of the two as similar is
justified. The basic configuration of unwind station, application/flashoff
area, drying oven, and rewind station is common to both. The VOC content
of the coatings found in the magnetic tape industry are within the range
of those found in the polymeric coating industry, and many of the same
solvents are used. Some coating application techniques are common to both
industries, and the mix equipment is often similar. The SLA streams
generated by the processes are similar in composition, as are the
applicable control technologies. Based on these considerations, EPA feels
it has made appropriate use of data derived from this industry. However,
the EPA does recognize that the magnetic tape coating process is largely
automated, requires little worker access compared to some polymeric
coating operations, and is characterized by a relatively narrow range of
coatings and substrates. It should be noted that the magnetic tape
industry data do not provide the basis of support for the polymeric
coating standard. Rather, data from the pressure sensitive tapes and
labels industry, flexible vinyl coating and printing, publication roto-
gravure, and the polymeric coating industry itself provide the basis for
the standard.
2. At least one air-atmosphere condenser has been used on a polymeric
coating operation. A representative of the plant indicated that no major
difficulties with the system had been encountered.9 However, it is
unlikely that this control technology will be used at polymeric plants
that are controlling mix equipment emissions as well as coating operation
emissions because the operation of a fine-tuned, closed-loop condenser can
2-34
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be adversely affected by the moist, intermittent airflow from mix
equipment. The use of an inert-atmosphere condenser was not analyzed
because use of this system is incompatible with a process where oxygen in
the application/flashoff area is essential for worker access. (See
Section 2.4.2.)
3. The assumption that the SLA stream at the inlet of the control
device has a concentration as high as 25 percent of the LEL is
justified. The standards contain no requirement that emissions from
solvent storage tanks be ducted to a control device. Moreover, a system
using dampers could be designed to deliver emissions from solvent storage
tanks to the control device at a concentration of 25 percent of the LEL.
Alternatively, a more dilute SLA stream could be used as makeup air in the
drying oven. Emissions from mix equipment are expected to be ducted to
the control device at a concentration of 25 percent of the LEL. In
addition, the airflow from this source 1s quite small in comparison to
that from the drying oven, so a reduced concentration would have little
effect on the overall concentration of the Inlet SLA stream. The air
containing the emissions from the applicatlon/flashoff area is expected to
be used as makeup air for the drying oven, not ducted directly to the
control device. Drying ovens in this and other industries are operated
safely at a concentration of 25 percent of the LEL. In fact, ovens
equipped with appropriate safety features are allowed to operate at up to
50 percent of the LEL.10
For the reasons presented above, EPA believes that the varied
production practices in this industry were adequately considered in the
standards development process and that the standards are achievable over
the range of production practices expected to occur.
2.3.1.4 Waterborne and Organic Solvent Coating Systems.
Comment: One commenter (IV-D-15) stated that there is no best
demonstrated technology for a coating operation that uses both aqueous and
organic solvent coating systems, nor is there a provision for handling
this type of operation where a common mixer is used.
Response: The commenter is correct that use of the proposed control
technologies may be incompatible with the use of waterborne coatings.
Therefore, an exemption for waterborne coatings has been added in
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§ 60.740, Applicability and Designation of Affected Facility, to specify
that the coating operation or mix equipment may be vented directly to the
atmosphere while waterborne coatings are used. A definition of waterborne
coatings sets the minimum water content (5 percent by weight of the
volatile fraction) necessary to be considered a waterborne coating.
Because "waterborne" coatings may actually contain organic solvent and
generate VOC emissions, the exemption for their use provides a VOC content
ceiling of 9 weight percent of the volatile fraction. This ceiling was
developed based on a "worst-case" baseline coating that is 85 percent VOC
(15 percent solids) by volume. The level specified in the exemption is
equivalent to a 90 percent VOC reduction for this coating. The VOC in
waterborne coatings is not to be included in the annual VOC usage rate
when determining if a facility is below the VOC use cutoff. However, the
amount of VOC in waterborne coatings reported by the industry is
negligible (zero to 2 percent by weight of coating applied) and the impact
of this exclusion is expected to be minor.11
2.3.2 Control of Coating Mix Preparation Equipment
2.3.2.1 Equipment Considered as Coating Mix Preparation Equipment.
Comment; One commenter (IV-D-3) recommended that coating mix
preparation equipment include only mixers and not mills, holding tanks, or
other equipment. The commenter observed that the only coating mix prepar-
ation equipment considered in developing the standards and demonstrating
the feasibility of the standards was the mix tank. The feasibility of the
proposed standard for mills, holding tanks, and other equipment, which are
included in the definition for coating mix preparation equipment, was not
considered. At the commenter's plant, portable containers are used to
transport coating from the mixing area to subsequent coating preparation
and application areas. These portable containers appear to be included in
the definition as "holding tanks," but, according to the commenter, there
is no feasible or practical way for these portable containers to comply
with the requirement that all VOC emissions be vented to a control device.
The commenter also questioned the feasibility of (1) capturing and venting
all VOC emissions from mills to a control device at a concentration range
within which the control device is efficient or (2) installing a vapor-
tight cover equipped with a conservation vent. The commenter said that
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only equipment that was specifically addressed in the development of the
standard should be included in the definition of coating mix preparation
equipment. The commenter recommended that "coating mix preparation
equipment" be defined as "mix tanks in which solvent and polymer are
blended to prepare polymeric coating formulations."
Response; The final rule requires that only affected mixing vessels
be covered and vented to a 95 percent efficient control device. The
definition of "coating mix preparation equipment" has been changed to "all
mixing vessels in which solvent and other materials are blended to prepare
polymeric coatings."
The commenter is correct in noting that only mixing vessels were
considered in the analysis of the cost and cost effectiveness of mix
equipment control. This approach was adopted because essentially all
mixing area emissions that were intended to be regulated are generated at
the mixers. Mills in this industry are most frequently operated using dry
ingredients alone and are often tightly sealed to contain the ingredients.
Emissions from holding tanks are negligible compared to those from the
mixers because both breathing and working losses are minimized. Breathing
losses are minimized because holding tanks are generally located indoors
at relatively constant temperatures and because the vessels typically are
covered during storage to minimize coating composition changes through
solvent loss and contamination. Working losses due to the filling of
vessels are minimized because holding tanks typically are cleaned between
uses; a clean, dry vessel does not have any vapor in the air space to be
displaced as the coating is introduced. Emissions during the cleaning
process are not regulated because of the inherent difficulties of
control. Nevertheless, mills, holding tanks, and other equipment were
included in the proposed rule because it had been determined that the
controls mandated for the mixers could be easily applied to such
equipment.
However, based on a reexamination of the information gathered during
the development of the standard and on the information presented by the
commenter, EPA has decided that the standards should be applied only to
mixers because they are the primary source of mix room emissions and the
costs of controlling emissions from mills were not demonstrated. The EPA
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also agrees with the commenter that it is infeasible to duct emissions
from portable equipment to a control device. However, during the actual
mixing process these portable containers are stationary and ducting
emissions to a control device is feasible. Thus, portable tanks,
including holding tanks, are required to be covered and vented during
those times that they are in use as mixing vessels.
2.3.2.2 Feasibility of 100 Percent Capture.
Comment; Three commenters (IV-D-3, IV-D-5, and IV-D-7) stated that
capture of all emissions from mix equipment has not been demonstrated.
The commenters questioned the technical feasibility of capturing and
venting all VOC emissions from coating mix preparation equipment.
One commenter (IV-D-3) whose plant was cited in the proposal preamble
as an example of BDT for mix equipment stated that the existing system
actually falls short of the technology specified as BDT. The mixer covers
are tight fitting but are not "sealed." The need for access to the mixers
makes sealed covers impractical. The plant has a system whereby dampers
open to increase the draft to the control device when mixer covers are
opened, but the commenter questioned the contention that all emissions are
prevented in this way. In addition, the commenter stated that EPA failed
to consider emissions during the transfer of coatings when EPA proposed
the requirement that all emissions from mix equipment be captured. Accord-
ing to the commenter, total enclosure of all transfers from mixers to
transfer containers, strainers, coaters, and other mixers is not feasible;
nor is it feasible to duct emissions from these transfer points or mix
equipment other than mixers (see Section 2.3.2.1) to the control device.
In addition, the commenter (IV-D-3) pointed out that, while the
proposal preamble states that BDT for mix equipment is the use of covers
vented to a control device and that the format for the standard is an
equipment format, the proposed standard does not mention equipment. The
commenter stated that: the requirement that all VOC emissions be captured
and vented makes the proposed standard a performance standard. The
commenter stated that as a performance standard the word "all" imposes a
condition that is impossible to meet because no engineered system is
100 percent effective, nor can it be operated with 100 percent reli-
ability. The commenter also stated that EPA does not present objective
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evidence to support the use of the terms "expected," "sufficient," and
"all" and does not define the term "sealed" in the proposal preamble,
Section IV(D)(l)(c). The commenter recommended that the performance
standard language be deleted and that the standard (§ 60.742(a)(2)as
proposed) be restated as an equipment standard as follows:
Control emissions from onsite coating mix preparation
equipment servicing coating lines using at least 150 m of
solvent/year by installing a cover on each piece of
affected coating mix preparation equipment and venting the
equipment to a 95 percent efficient control device; the
cover must be closed at all times except when adding
ingredients, withdrawing samples, transferring the con-
tents, or making visual inspections when such activities
cannot be carried out with covers in place; when possible,
such activities should be carried out through ports of the
minimum practical size. . . .
A second commenter (IV-D-5) focused on the portable containers or
"change cans" used specifically in the printing blanket industry for high-
viscosity coatings that cannot readily be pumped beyond the shortest
distances. According to the commenter, the change cans are generally
covered during storage, movement, and mixing .but cannot be ducted to a
control device because of their portable nature. Some VOC emissions from
these containers are inevitable when covers are necessarily removed
between the steps of the process. The commenter noted that EPA estimates
that coating mix preparation equipment accounts for only 10 percent of the
VOC emissions from a coating plant. The comnenter suggested that the
final rule allow the use on change cans of a plastic film cover at least
2 mils thick and taped around the periphery during storage, transport, and
piping of coating to the coating heads, which would result in control at a
"somewhat" less stringent standard. Fixed covers with conservation vents
are not a viable alternative based on the commenter's experience that such
covers are too heavy to be handled manually in a safe manner and that the
use of mechanical equipment is cumbersome and may damage the cover,
reducing its effectiveness as a control device. The commenter reiterated
these comments in Docket Item IV-D-16 and added that the minimum measured
VOC concentration at the carbon adsorber outlet was 25 ppm, which would
result in no net VOC reduction because of the low level (probably 10 to
25 ppm) of VOC in the air from the mixing room.
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The third commenter (IV-D-7) pointed out that companies frequently
use different types and sizes of mix equipment. Some are totally
enclosed, while others are virtually impossible to enclose well enough to
meet the proposed standard. The size of containers varies from a 5-gallon
pail to a 500-gallon portable tank. The commenter maintained that
companies would find it impossible to capture all emissions from mix
equipment because of the nature of the process, cleanups, color changes,
short runs, container handling, etc. The commenter also questioned the
validity of EPA's contention that coating lines that apply urethane
coatings, which are purchased premixed, do not use mix equipment.
According to the commenter, all such operations use mix equipment either
to adjust the specific properties of a batch of coating or to obtain the
proper coating consistency.
Response; The format of the standard for mix equipment was intended
to be an equipment standard. But, as noted by the commenters, the use of
the term "all" in the proposed standard implies 100 percent capture, which
has not been demonstrated in the polymeric coating industry. The
standards for mixing vessels that serve coating operations that use at
least 130 Mg/yr (144 tons/yr) of VOC (and are not associated with a
coating operation without concurrent construction of a control device)
have been revised to be consistent with actual workplace conditions as
described by the commenters. These mixing vessels are required to be
covered during mixing and vented to a 95 percent efficient control
device. The covers shall be closed at all times except when adding
ingredients, withdrawing samples, transferring the contents, or making
visual inspection when such activities cannot be carried out with the
cover in place. The cover must extend at least 2 centimeters (cm)
(0.8 inch (in.J) beyond the outer rim of the equipment or be attached to
the rim and must be of such design and construction that contact is
maintained between cover and rim along the entire perimeter. Any breach
in the cover (such as a slit for insertion of the mixer shaft or port for
addition of ingredients) must be covered as discussed above when not
actively in use. An opening sufficient to allow safe clearance for a
mixer shaft is acceptable during periods when the shaft is in place. A
polyethylene or other nonpermanent cover may be used provided it meets the
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requirements above. Such covers may not be reused after once being
removed. As discussed in Section 2.3.2.1, the requirements for mix
equipment other than mixing vessels have been dropped from the final rule.
The EPA does not believe that the use of portable containers or
containers of varying sizes precludes the venting of emissions to a
control device during the actual mixing process. In cases where portable
tanks are used, the mixing apparatus remains stationary. Ductwork can be
installed from this point to the control device. No evidence has been
presented that small mixing vessels cannot be similarly equipped. The
intent of the proposed mix equipment standards was not to require ducting
of the ventilation air from the entire mix room to the control device but
to allow installation of ductwork at the mixing station, which would
provide a higher solvent concentration for more efficient control. The
change from requiring the control of "all" mix equipment emissions to an
equipment format, with allowances for opening covers during periods of
legitimate need, addresses the concerns cited by the commenters.
The commenter's (IV-D-7) contention that sources applying urethane
coatings employ mix equipment does not change the conclusions of the
background study. Should these sources use mix equipment, the same cost
factors that apply to mix equipment at other plants would apply. In fact,
the higher value of the solvents saved by the application of control tech-
nology at this type of plant would improve the cost effectiveness of
control beyond that calculated for other types of polymeric coating
plants. Because of the direction of this change, the impacts of the
standards were not recalculated. When such sources use mixers, the
beneficial impacts of the standards will be obtained with reasonable cost
effectiveness and will far outweigh the negative impacts.
2.3.2.3 Efficiency of Mix Equipment Covers.
Comment; One commenter (IV-D-3) said that EPA appears to have
incorrectly applied information on emissions from solvent storage tanks to
emissions from mix tanks. The resulting estimate that vapor-tight covers
with conservation vents would reduce emissions by 40 percent significantly
understates the emission reduction that would be obtained. The commenter
went on to say that even a simple cover not equipped with vapor-tight
seals or a conservation vent would conserve much more than 40 percent of
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the solvent lost from an open mixer. The commenter presented the results
of a bench-scale experiment testing this hypothesis. A Pensky-Martens
flashpoint tester was used with a small amount of coating to approximate a
mixer. It was reported that, relative to an uncovered mixing vessel,
covers over 87 percent and 100 percent (not vapor tight) of the vessel
opening achieved emission reductions of about 74 percent and 96 percent,
respectively. The commenter contended that economic analysis would show
that the small gain in emissions control achieved by a vapor-tight cover
with a conservation vent as opposed to a simple cover would not be cost
effective. The commenter suggested that the standard for mix equipment
using at least 110 m;}/yr (29,059 gal/yr) (95 Mg/yr [105 tons/yrj) but less
than 150 m3/yr (39,626 gal/yr) (130 Mg/yr [144 tons/yr]) of VOC
(§ 60.742(a)(3) as proposed) be revised to require only a cover that
encloses at least 95 percent of the opening and that must be closed at all
times except when adding ingredients, withdrawing samples, transferring
the contents, or making visual inspection when such activities cannot be
carried out with the cover in place.
Response; The EPA agrees that the improvement in control efficiency
on mix equipment to be gained from a vapor-tight cover with a conservation
vent compared to that from a simple tight-fitting cover is insignificant.
The chief benefit to be gained from conservation vents is the control of
"breathing losses" resulting from diurnal temperature changes. Because
mix equipment is not normally exposed to such changes in this industry,
the requirement that covers be sealed and equipped with conservation vents
has been dropped. However, EPA does not agree that the emission reduction
ascribed to covers is significantly underestimated. The experiment
conducted by the commenter explored only evaporative losses during the
mixing process. This treatment neglects the impact of the "working
losses" that occur due to the filling and emptying of a vessel that
contains a solvent-saturated air space. An analysis of cover efficiency
was carried out for mix equipment in the magnetic tape manufacturing
industry, and the results of this analysis are considered representative
of the polymeric coating industry as well.12 The efficiency of covers was
determined by this analysis to be 40 percent.
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The standard for mixing vessels that use at least 95 Mg/yr
(105 tons/yr) but less than 130 Mg/yr (144 tons/yr) of VOC, § 60.742(c)(3),
has been revised to require the equipment to be covered at all times except
when adding ingredients, withdrawing samples, transferring the contents, or
making visual inspection when such activities cannot be carried out with
the cover in place. The same requirements have been extended to mix
equipment at facilities using at least 130 Mg/yr (144 tons/yr) of VOC that
are associated with coating operations without concurrent construction of
a control device. The cover must extend at least 2 cm (0.8 in.) beyond
the outer rim of the equipment or be attached to the rim and must be of
such design and construction that contact is maintained between cover and
rim along the entire perimeter. Any breach in the cover (such as a slit
for insertion of the mixer shaft or port for addition of ingredients) must
be covered as discussed above when not actively in use. An opening suffi-
cient to allow safe clearance for a mixer shaft is acceptable during
periods when the shaft is in place. A polyethylene or other nonpermanent
cover may be used provided it meets the requirements above. Such covers
may not be reused after once being removed. The cost of compliance with
the revised standard will be less than that associated with the use of
covers and conservation vents, which were cost effective under the
proposed standard. This is because the cost of covers is expected to be
included in the purchase price of new equipment so that there is no
incremental cost associated with the emission reduction.
2.4 CONTROL COSTS
2.4.1 Total Enclosure of Print Blanket Coating Equipment
Comment; One commenter (IV-D-5) stated that the cost of totally
enclosing print blanket coating equipment was seriously underestimated.
This segment of the polymeric coating industry uses very viscous coatings
that must be applied in precise thickness according to strict specifica-
tions. The operator must constantly observe for dirt contamination or
accumulations of dried coatings on the back of the blade and inspect for a
smooth appearance of the coating. These factors necessitate constant
operator access to the coater. Thus, according to the commenter, a small
enclosure immediately around the coating application/flashoff area cannot
be used. The commenter also stated that a total room enclosure is
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infeaslble for existing plants (see Section 2.11.1), because there are
typically multiple lines In a single large room with many openings and
ventilation systems. The remaining option 1s to enclose the equipment
within a smaller room of sufficient size to allow the constant presence
and mobility of equipment operators. However, for worker safety, the
concentration of solvent within this enclosure is currently limited to
100 parts per million by volume. According to the commenter, this limit
cannot be achieved using a blower system to supply fresh air to the area
where the operator is stationed because of the large size of the equipment
(up to 80 feet long) and the requirement that the workers be able to move
about the equipment to monitor and adjust critical parameters. The
commenter also rejected the use of airpacks, which are a serious incon-
venience to the worker. The commenter concluded that the only remaining
option would be to flush high volumes of air through the enclosure to
maintain the low solvent concentration required for employee safety.
The commenter presented an analysis of the costs and cost
effectiveness of this approach at one of his company's print blanket
coaters. The analysis was based on the capture of an additional
110 pounds of toluene per hour. To dilute this quantity of solvent to the
safe concentration, the air handling system would have to be designed for
approximately 77,000 cubic feet of air per minute. The commenter stated
that an additional carbon adsorption system sized to handle this airflow
would cost approximately $2.5 million. The cost-effectiveness calcula-
tions were based on the actual solvent use for the subject coating line.
(Many of the details of this analysis were claimed to be confidential
business information and are not presented here.) The commenter1s
analysis, taking Into account capital depreciation, steam costs, power
costs, and solvent recovery credits, resulted in a cost effectiveness of
$21,005 per ton of solvent recovered relative to the emission level
currently allowed by State regulations, which is represented by Regulatory
Alternative I.
Response; The commenter's analysis of costs and cost effectiveness
was based on the faulty assumption that the only way to protect workers
within a total enclosure is to assume that the emissions are released into
the enclosure and to dilute the emissions in the enclosure to the level
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considered safe for personnel. This assumption resulted in an airflow
rate so high that an entirely new carbon adsorption system would be
required to control the emissions. The capital cost of this system,
coupled with the high operating costs associated with maintaining a high
removal efficiency from such a dilute SLA stream, resulted in an
unreasonable cost-effectiveness value.
The commenter's assumption is unrealistic and erroneous. In
practice, localized pickup points (hoods or other partial enclosures)
should be placed within the total enclosure to both protect any workers
that must be inside and reduce the ventilation rate to a level such that
the air from the enclosure can be used as makeup air in the drying oven.
Thus, a new carbon adsorption system would not be required, and the
composition of the SLA stream ducted to the control device would be
similar to that assumed in EPA's analyses.
The EPA reworked the commenter's analysis using more realistic
assumptions. Based on the use of local ventilation devices within a total
enclosure, a reasonable concentration for the captured fugitive VOC is
5 percent of the LEL. The ventilation rate of the enclosure under these
conditions would be about 12,000 actual cubic feet per minute. Given the
drying requirements in the oven under the commenter's scenario, this
quantity of ventilation air could be readily accommodated as makeup air
for the drying oven, and a new carbon adsorber would not be necessary.
Using the commenter's values for annual VOC use, electricity and steam
costs, and the value of reclaimed solvent and the factors from EPA's
original analysis for adsorber steam and electricity demand, the cost
effectiveness of moving from the source's current control level to the
level required by the NSPS is less than $200 per ton of additional solvent
recovered. The EPA considers this to be a reasonable value. Thus, EPA
believes that the costs associated with totally enclosing equipment such
as that operated by the commenter were not underestimated.
2.4.2 Accuracy of Cost Analysis
Comment; Three commenters (IV-D-7, IV-D-8,. IV-D-14) questioned the
assumptions and models used in performing the cost analyses. The
commenters noted the following specifics:
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1. Leak-proof ovens. One commenter (IV-D-7) stated that the
efficiencies used 1n the cost analysis were based on leak-proof ovens,
which are virtually impossible to construct. The commenter suggested that
the efficiencies be based on demonstrated efficiencies such as monthly
averages rather than the maximum efficiency achieved over a short
period. Also, operating efficiencies for process lines are lower than
vendors' claims.
2. Recovered solvent credit. Each of the commenters (IV-D-7,
IV-D-8, IV-0-14) stated that the cost credit from recovered solvent is
lower than the estimates in the proposed regulation. One commenter
(IV-D-7) stated that the costs were based on recovery of a single solvent
rather than mixed solvents, which are typically used in the industry.
Mixed solvents may have to be disposed of as hazardous wastes. The other
commenters (IV-D-8, IV-D-14) noted that the cost analysis did not address
processes for which the solvent cannot be reused. One commenter (IV-D-8)
said that recovered solvent would probably not meet the stringent quality
standards required for solvents used 1n aerospace and defense applica-
tions. The second commenter (IV-D-14) stated that solvent recovery is not
a viable alternative for fabric coating of labeling material for the
garment Industry because of the high purity solvents required. This
commenter said that recovered solvents would likely have to be disposed of
as hazardous waste. The commenter also stated that incineration would be
prohibitive because of the large volume of air and low VOC concentration.
3. Air-atmosphere condensation. One commenter (IV-D-7) stated that
the cost data were based on an air-atmosphere condensation system that has
not been demonstrated as a feasible technology for the polymeric coating
industry. The cost of modifications required to apply this technology to
the polymeric coating Industry was not considered in the analysis.
4- Costs of air pollution and wastewater controls. One commenter
(IV-D-7) stated that the cost of air and wastewater pollution control
equipment was not addressed. Specifically, the commenter cited that the
cost of distillation systems, which are needed to purify solvents and
clean up wastewaters, was not included in some models, and that the
capital costs for air pollution control equipment, which refer to a 1978
manual, seem low. A second commenter (IV-D-8) stated that the economic
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Impact of wastewater discharges should be reassessed because of the
recently passed Clean Water Act amendments. The preamble to the proposed
standards states that carbon adsorber wastewater discharges to municipal
sewer systems are permissible, but the commenter suggested that pretreat-
ment may be required by the recent Clean Water Act amendments.
Response; The EPA continues to believe that the assumptions used in
the cost analysis are valid and that the model plants are representative
of typical facilities expected to be constructed, modified, or recon-
structed in the near future. The following responds to the specific
comments summarized above:
1. First, EPA believes an essentially leak-proof oven is possible
with proper design and operation at a slightly negative pressure relative
to its surroundings. Second, the standards were based on demonstrated
effldences. An overall efficiency of 93 percent has been demonstrated
using a 30-day material balance at a PSTL facility using BDT (See
Section 2.3.1.1). This performance is considered representative of the
performance of a well-designed and well-operated control system in the
polymeric coating Industry. Thus, demonstrated performance over a 30-day
period was considered 1n the development of the standards.
2. The EPA's survey of existing plants indicates that typical
practice for the polymeric coating industry 1s to use a single solvent or
a reusable mixture, rather than mixed solvents that may have to be
disposed as stated by the commenter (IV-D-7). However, the model lines
analyzed by EPA also accounted for the use of two types of solvents that
required distillation, a two-solvent blend (dimethyl formamide and
toluene) and a water-soluble solvent (acetone). In both cases, it was
determined that control at the level of the standard is cost effective.
Onsite distillation is expected to become more attractive as
regulations on the disposal of liquid hazardous wastes become more
restrictive. As the cost of such disposal rises, the relative benefit of
distillation increases. Thus, while the cost of reclaiming solvents may
not be justified by the value of the solvents themselves, it may be
justified when the cost of disposal is considered. If onsite distillation
remains infeasible, and the solvent is sold to a reclaimer or disposed as
a hazardous waste, the operator will not accrue full value of the
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solvent. However, the same will hold true under any of the regulatory
alternatives; therefore, the incremental cost to go from one regulatory
alternative to the next most stringent regulatory alternative would in
most cases be small, and the regulatory decisions would not change.
As one commenter pointed out, the inability to reuse solvents is most
likely to occur in aerospace and defense applications because of stringent
quality specifications for solvents. However, EPA is working with the
Department of Defense to encourage development of end-product specifica-
tions. This may enable the defense industry to reuse solvents. If
solvents are not recovered and reused, the economic impact to the aero-
space and defense industries is expected to be small. Incineration is
currently used, without adverse economic impacts, as a VOC emission
control measure for these industries (including the commenter's [IV-D-8]
plant that was visited during the background study).
As discussed in the response to Comment 2.3.1.1, even solvent
recovery credits less than 100 percent (i.e., 60, 30, and 0) result in
reasonable control costs in the majority of cases. However, where carbon
adsorption control is not cost effective, incineration is a viable
alternative that has been successfully used by the polymeric coating
industry.1*
3. At least one polymeric coating plant has operated an
air-atmosphere condensation system. At the time the cost analyses for the
standard were performed, this condensation system had not been in opera-
tion long enough for meaningful efficiency data to be collected. However,
preliminary data indicated that the air-atmosphere condensation system
would be a viable option. A recent discussion with a representative at
the polymeric coating plant that uses an air-atmosphere condensation
system supported this conclusion.9 The air-atmosphere condenser at this
plant achieves a control efficiency of 90 to 95 percent. There have been
no problems with this system during approximately 3 years of operation.
However, as a result of EPA's analysis of the cost and performance of
various technologies applicable to the polymeric coating industry, carbon
adsorption, not air-atmosphere condensation, was chosen as the BDT on
which the standard 1s based. In addition, it is anticipated that most
affected lines, which will also have to duct and control mix equipment
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emissions, would be unable to use condensers because the moist,
intermittent airflow from mix equipment interferes with condenser perfor-
mance. The cost of an inert-gas atmosphere condenser was not developed
because of its limitations for application in this industry (i.e., the
need to purge the unit of inert atmosphere every time workers must access
the oven or application/flashoff area).
The costs to fit a coating operation with an air-atmosphere condenser
were included in EPA's analyses. These costs consist of the costs of the
total enclosure and ductwork.
4. The cost of distillation systems was included for all models
requiring distillation, that is, those.model coating operations using a
solvent blend or a water-soluble solvent. Capital costs for a condenser
were developed from estimates provided by a vendor. Capital costs for an
incinerator and carbon adsorber were developed using the 1978 Economic
Analysis Branch Control Cost manual. However, these costs were adjusted
to 1984 dollars using the Plant Cost Index in Chemical Engineering. (All
costs are reported in first quarter 1984 dollars.)
The commenter (IV-D-8) correctly points out that wastewater generated
because of compliance with the polymeric coating NSPS may be subject to
either effluent limitations if the wastewater is discharged to a receiving
stream or pretreatment standards if the wastewater is discharged to a
municipal sewer. Both the wastewater generated because of compliance with
the polymeric coating NSPS and the wastewater generated currently because
of compliance with existing State pollution regulations for VOC emissions
have to meet the applicable treatment requirements. Because the treatment
requirements have to be met under baseline conditions for wastewater
discharged currently and because the increase in the volume of wastewater
generated after compliance with the polymeric coating NSPS is small, the
cost to treat the wastewater was not included in the costs used in the
economic evaluation of the technology alternatives for the NSPS. The
small Increase in treatment costs because of the additional volume of
wastewater generated after compliance with the NSPS would affect neither
the results of the economic analysis of the technology alternatives nor
the selection of the technology used as the basis for the polymeric
coating NSPS.
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2.5 ENVIRONMENTAL IMPACTS
2.5.1 Total Enclosure Requirement
Comment; One commenter (IV-D-5) believed that EPA failed to account
for the environmental advantages of high-solids coatings. The commenter
stated that the need for constant operator access and attention while
applying the current high-solids coating formulations used in printing
blanket coating operations render the proposed standards economically
infeasible (see Section 2.4.1). To avoid this problem, a printing blanket
manufacturer contemplating a new coating line might attempt to develop a
new process that utilizes a low-solids coating formulation so that port-
able mix equipment and constant operator access to the coater are not
required. Such a process might comply with the proposed mix equipment and
coating operation standards while actually increasing emissions relative
to existing practice using high-solids coatings. (The commenter presented
an example of such a situation, but many of the details were claimed to be
confidential business information and, thus, are not presented here.) The
commenter suggested that Regulatory Alternative I, the prevailing SIP
limit in nonattainment areas, be adopted in the final rule.
Response; The EPA does not believe that any manufacturer would need
to develop a new process using a low-solids coating formulation in order
to comply with the standards. The commenter's assertion that a total
enclosure would be Infeasible for his company's high-solids coating
operation was based on faulty assumptions (see Section 2.4.1). Also, a
revision to the definition of coating mix preparation equipment excludes
the portable mix equipment described by the commenter except during those
periods when the portable vessels are in use as mixing vessels (see
Section 3.2.1). Thus, the hypothetical scenario presented by the
commenter is not expected to occur. The EPA has demonstrated that the
final standards (with a solvent use cutoff to exempt small sources)
provides a greater emission reduction than would be achieved under base-
line conditions for a reasonable cost. The commenter has not provided
information that would change this determination.
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2.5.2 Accuracy of Environmental Impact Analysis
Comment; One commenter (IV-D-9) questioned the accuracy of the
environmental and economic impact analyses because of discrepancies in the
data base for existing plants. The commenter stated that only 6 of the
13 Ohio plants listed in Table 9-7 of the Volume I BID (Plants Applying
Polymeric Coatings to Supporting Substrates . . .) actually apply a
polymeric coating; the others apply a printing ink to vinyl or vinyl
fabric. The commenter provided a list of the 13 plants and the process
used at each plant. The commenter stated that this discrepancy "casts a
shadow" over the analyses of environmental and economic impacts.
Response: The environmental and economic impact analyses were based
on a projection of sources expected to become subject to the NSPS in the
next 5 years. These sources are expected to be new coating lines rather
than modified or reconstructed lines. The analyses were performed using
model lines developed from information about existing polymeric coating
plants that are considered to be representative of new polymeric plants,
and not using the list of existing sources presented in Table 9-7 of the
Volume I BID. Thus,, any Inaccuracies 1n the Information presented in
Table 9-7 would not affect the environmental or economic impact analyses.
2.5.3 Baseline Control Level
Comment; Two commenters (IV-D-5, IV-D-9) questioned the determination
of the baseline emission level for coating operations. One commenter
(IV-D-5) stated that; the designated baseline, Regulatory Alternative I,
actually represents a control level that would require significant reduc-
tions in emissions from many coating operations. Many State regulations
allow a level of control that is considerably more lax than Regulatory
Alternative I, and various States that do require this level allow excep-
tions under some circumstances. On the basis of this and the analysis in
Section 2.5.1, this commenter suggested that Regulatory Alternative I be
adopted in the final standards. The second commenter (IV-D-9) noted that
some fabric coating plants in Ohio had variances from the SIP control
level requirement.
Response; The baseline control level is defined as the existing
level of control that is typical for the Industry. The baseline emission
level used in the analyses for coating operations is 0.35 kilogram of VOC
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per liter of coating (kg VOC/i) (2.9 pounds of VOC per gallon of coating
[15 VOC/gal]). This level is the most prevalent and among the most
stringent of the State standards. Because it is uncertain where faci-
lities subject to the NSPS will be located and it is uncertain whether
these facilities will be exempt from a particular State's standards,
0.35 kg VOCA (2.9 Ib VOC/gal) was judged to be the best choice for
baseline. If actual SIP requirements affecting a significant portion of
the industry are, in fact, less stringent than this baseline level, the
emission reductions for the regulatory alternatives have been under-
estimated, and average cost-effectiveness values have been overstated.
Because the choice of a baseline level of 0.35 kg VOCA (2.9 Ib VOC/gal)
results in a conservative analysis, raising the baseline emission level
would not alter but would actually reinforce the selection of the level of
the final standards.
2.6 ECONOMIC IMPACTS
2.6.1 Accuracy of Economic Impact Analysis
Comment; One commenter (IV-D-7) believed that the economic impact
was underestimated because the analysis was based on faulty data (see
Section 2.3.1.3). The Volume I BID states that for all regulatory
alternatives other than Regulatory Alternative IV, the use of incinera-
tion, price and cost increases would be relatively small. However, the
commenter contended that incineration is the only control method that
could achieve compliance with the proposed standard.
A second commenter (IV-0-12) stated that because the enclosures
recommended by EPA would create LEL concentrations that are unacceptable
for current insurance coverage, insurance rates would increase and it may
become difficult to get coverage. The commenter stated that this
increased cost would be passed on to the customers, decreasing their
competitiveness.
Response; As discussed in Sections 2.3.1.1 and 2.3.1.3, available
data support the selection of carbon adsorption system as BOT, even under
the variable operating conditions discussed by the commenter. However,
EPA does acknowledge that incineration may be cost effective in some
situations. In any case, EPA maintains that the economic impact of the
standards was correctly determined and supports the selection of
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90 percent overall control, for which price and cost increases are
relatively small, as the basis for the coating operation standard.
The LEL insurance requirements for enclosures are the same as for
ovens, i.e., enclosures would typically have to be maintained at less than
25 percent of the LEL. Analysis has indicated that a local ventilation
system in the application/flashoff area can be constructed so that the
bulk of the drying oven makeup air is drawn through the system, carrying
nearly all the emissions from this area with it.2 The very low level of
emissions escaping from such a local capture system would be far below the
level necessary to approach 25 percent of the LEL in the surrounding
area. In fact, a well-designed system would achieve sufficient capture to
maintain a safe level of worker exposure (i.e., a concentration below the
TLV) in the coating room. The concentration within the capture system
also would be well below 25 percent of the LEL. Emissions in the
application/flashoff area typically are on the order of 10 percent of
total emissions from the coating operation. Using most of the oven makeup
air (which is sufficient to dilute the 90 percent of the solvent
volatilized in the drying oven to below 25 percent of the LEL) to capture
this fraction of the total emissions will result in an SLA far below
25 percent of the LEL. Therefore, fire hazard and worker exposure will
not increase as a result of the NSPS, and insurance rates would not be
adversely affected. For these reasons, no changes have been made to the
economic analysis.
2.6.2 Trend Toward Reduced Solvent Usage
Comment; One commenter (IV-0-7) stated that a continued trend toward
reduced solvent usage as projected in the economic analysis may not be
accurate. The commenter noted that certain high-specification and
defense-related products must be made with solvents and must continue to
be manufactured in the United States.
Response; The number of new facilities likely to become subject to
the standards from 1986 to 1990 was derived from the estimated percentage
of industry production using organic solvent-based coatings and the
estimated change in industry capacity required to meet market demand
during this 5-year period. The percentage of production using organic
solvent-based coatings for each year was based on a linear extrapolation
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of values from 1976 and 1981.15 The calculated VOC use factors and new
VOC-based production capacity requirements for the 5-year period are
presented in Table 9-18 (page 9-44) of the Volume I BID. The estimated
number of new facilities and potential total fifth year net annualized
costs that would result from adoption of the most costly regulatory
alternatives are presented in Table 9-19 (page 9-48) of the Volume I BID.
If, as suggested by the commenter, the reduction in VOC use were less
than that projected over the 5-year period, there would be a larger number
of facilities subject to the standards, and the total fifth year net
annualized cost would be greater than that presented in the Volume I
BID. However, this would have no affect on the economic impacts of the
standards. Production cost and price impacts were calculated based on
individual facilities and products and would not be affected by the
increase in the total number of affected facilities.
If the VOC use factor were to remain constant at its 1981 level
instead of continuing the downward trend noted between 1976 and 1981, the
estimated new VOC-based production capacity necessary to meet projected
market demand would approximately double. As a result, the total number
of new facilities and the total net annualized costs shown in Table 9-19
(page 9-48) of the Volume I BID would also nearly double. As a
consequence of this change, the potential worst-case fifth year net
annual1zed cost of the standards would increase from $1.86 million to
about $3.7 million. Thus, even if the VOC use factor is assumed to remain
constant, the total estimated fifth year cost 1s considerably less than
the $100 million listed in Executive Order 12291 as indicative of a "major
rule."
If the number of facilities subject to the standards were nearly to
double, the environmental and energy impacts would be similarly Increased.
Thus, the reduction 1n nationwide VOC emissions in the fifth year would be
about 2,400 Mg beyond the emission level stated in the typical SIP. All
impacts would be Increased proportionally, so the judgment based on the
original analysis that the beneficial impacts outweigh the negative
impacts would not be altered.
The original analyses performed by EPA have not been revised as a
result of this comment. In EPA's judgment, the estimation techniques used
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previously remain valid. The commenter only speculated that the
"projection may not be accurate" and offered no data to support this
contention. As mentioned in Section 2.4.2, EPA is working with the
Defense Department toward end-product specifications that have the
potential of allowing increased use of low-solvent coatings in defense
applications. Because a change in the trend toward reduced VOC use in
this industry would have no effect on the production cost and price
impacts of the standards and the other impacts would be affected
proportionally, EPA sees no need for new impact analyses.
2.6.3 Industry Growth
Comment; One commenter (IV-D-15) questioned EPA's estimate that
18 new solvent-borne lines would be constructed by 1990. The commenter
predicted that, if the proposed regulations go into effect, no new lines
would be built in the U.S. because EPA has failed to demonstrate that
available technology can achieve the required emission reductions. The
commenter continued to say that no company can afford to invest in new
equipment without data to demonstrate that it will meet environmental
requirements. The commenter also stated that without relief, textile
coaters could not expand nor could they successfully compete with foreign
imports. Another commenter (IV-D-11) stated that no new lines other than
low-solvent lines will be built in the U.S. and expansion of solvent-borne
lines will move overseas. A third commenter (IV-D-18) stated that their
industry, which is one of the largest specialty fabric commission coaters
in the U.S., could not grow or may not even survive if they do not get
some relief from the proposed standards. A second commenter (IV-D-16)
stated that the standards, as proposed, would prevent the addition of new
equipment and the modification of existing equipment at their older
plants.
Response; Because the standards for coating lines are achievable and
cost effective for all segments of the polymeric coating industry (see
Section 2.3.1.1 and Chapter 8 of the Volume I BID), EPA continues to
support its estimate that 18 new lines will be constructed in the U.S. by
1990. The EPA believes that most affected facilities will choose to
demonstrate compliance for coating operations by the alternative standard
(§ 60.743(b)), which requires a total enclosure vented to a 95 percent
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efficient control device. These provisions have been clarified by adding
design and operating specifications for a total enclosure. This should
simplify the process of obtaining approval for a total enclosure and
reassure Industry that compliance can be demonstrated for new equipment
that 1s properly designed and operated. The EPA also continues to support
its position that the standards are achievable for most coating lines that
would be modified or reconstructed.
2.7 COMPLIANCE
2.7.1 Control Device Downtime
Comment; One comnenter (IV-0-3) stated that the standard should
allow for the fact that solvent recovery systems are not 100 percent
reliable and that some downtime is inevitable. The commenter cited design
deficiencies, steam and electric interruptions, mechanical breakdowns, and
major maintenance such as replacing the carbon or overhauling components
as causes for downtime. Since it 1s not always feasible to shut down
production during these Interruptions, the commenter recommended that
enforcement be based on failure to correct a solvent recovery system
deficiency 1n a reasonable time, rather than on the occurrence of such a
deficiency.
Response; The EPA recognizes the Inevitability of air pollution
control equipment downtime and accounts for this 1n the General Provi-
sions. Section 60.8(c) (Performance tests) states that emissions in
excess of the applicable emission limit during periods of malfunction are
not considered a violation unless otherwise specified in the applicable
standard. The polymeric coating standard does not specify that excess
emissions due to malfunctioning air pollution control equipment trigger a
violation. "Malfunction" is defined in § 60.2 (Definitions) as "any
sudden and unavoidable failure of air pollution control equipment or
process equipment or of a process to operate 1n a normal or usual manner.
Failures that are caused entirely or in part by poor maintenance careless
operation, or any other preventable equipment breakdown shall not be
considered malfunctions."
Section 60.7(b) (Notification and Recordkeeping) requires that
records of the occurrence and duration of any malfunction of air pollution
control equipment be maintained. Also, § 60.11(d) (Compliance with
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standards and maintenance requirements) requires that at all times,
including periods of malfunction, owners and operators shall, to the
extent practical, maintain and operate any affected facility including
associated air pollution control equipment in a manner consistent with
.good air pollution control practice for minimizing emissions. Information
used to determine whether operating and maintenance procedures are
acceptable includes monitoring results, opacity observations, review of
operating and maintenance procedures, and inspection of the source. Thus,
the reporting of an exceedance is only an indication that the facility may
not be in compliance.
2.7.2 Comp1iance Provisions
Comment; One commenter (IV-D-16) sought confirmation that under the
proposed regulations compliance could be demonstrated with an "approved"
room enclosure around the coating equipment and data that indicate proper
operation of collecting equipment. The commenter's interpretation is that
the design of the room enclosure will be approved by EPA on a case-by-case
basis and that the major requirement for approval is that the room be
under negative pressure and the exhaust which produces this negative
pressure be vented to a 95 percent efficient control device. Data to prove
proper operation of the control device would be taken from continuous
recordings of the pollutant concentration in the gas vented from the
carbon beds.
Response; The final standards have been revised to clarify that the
use of certain equipment, i.e., a total enclosure and a 95 percent
efficient control device, is available as an alternative standard to the
90 percent emission reduction standard. In other words, the owner or
operator may choose to comply with either the emission reduction standard
or the alternative standard. The EPA also has revised the compliance
provisions to include specifications for a total enclosure. Case-by-case
approval by the Administrator is not required if these specifications are
met. After the initial determination of compliance, an approved parameter
(such as fan amperage or duct flow rates) shall be monitored to demon-
strate proper operation of the vapor capture system. Also, the control
device must be monitored in accordance with the same provisions that apply
when the two-part gaseous emissions test is used to demonstrate
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compliance. If the control device is a carbon adsorber, monitoring of the
pollutant concentration in either the control device outlet stream or both
inlet and outlet streams is required.
In addition, the compliance provisions for coating operations meeting
the emission reduction standard have been clarified and revised since
proposal. In the final standards, one method of demonstrating compliance
is to perform a two-part gaseous emissions test to measure both capture
efficiency and control device efficiency. Compliance is demonstrated if
the product of these two efficiencies is equal to or greater than 0.90.
This compliance method is available to all affected facilities. Another
alternative to performing the gaseous emissions tests is performing a
liquid-liquid material balance. However, this compliance provision has
limited applicability. A liquid-liquid material balance can only be used
when a single coating operation is vented to a dedicated control device
(i.e., the control device may not be used to control emissions from any
other emission source, including mix equipment). This compliance
provision is most likely to be applicable for facilities with mix
equipment that is not; required to be vented to the control device. The
liquid-liquid material balance compliance provisions include two
options. The first option requires that a liquid-liquid material balance
be performed for each nominal 1-month period. When using this option, no
monitoring is required beyond that necessary to perform the material
balance. The second option, which has been added since proposal, requires
performing a one-time material balance over 3 to 7 days followed by con-
tinuous monitoring. The number of days for the performance test is
selected by the operator and shall provide data that represent the plant's
typical coating practices. The monitoring requirements are the same as
those specified for the two-part gaseous emissions test and alternative
standard. This second option may be attractive for facilities that cannot
or do not want to conduct the detailed continuous monthly liquid material
balance measurements that are required for an accurate balance (e.g., VOC
applied at the coater, retained VOC [optional], VOC waste losses).
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2.8 TEST METHODS AND MONITORING
2.8.1 Proposed Compliance Provisions
Comment; One commenter (IV-D-1) stated that the 93 percent reduction
required of coating operations will be unattainable because of the inher-
ent vagaries of the parameters that must be measured to perform the liquid
material balance compliance test. The commenter stated that the method
requires measurement techniques that are not currently used. Factors
anticipated to affect the accuracy of the measurements are residual
materials left in dip tanks, the change in solvent concentration during a
normal process run, and water entrained in the recovered VOC following
carbon adsorption.
The commenter stated that the measurement techniques and formula for
the control device efficiency in the gas balance compliance test are
realistic but that the formula for capture efficiency appears to assume
that all uncontrolled solvent vapors will be discharged through a
measurable point and! that there will be no "stray" fugitive emissions.
Response; The EPA acknowledges that short-term variations in process
conditions could affect a facility's ability to perform the measurements
required to demonstrate compliance in the short term by means of a liquid
material balance. For this reason, a relatively long averaging time (in
this case, 1 month) is available to allow for a representative variety of
coatings and products, as well as to reduce the impact of short-term
variations due to process upsets, solvent spills, and variable amounts of
solvent in use in the process (Vol. I BID, p. D-16). Facilities should
already keep at least some of the required records as part of normal
business practices and should be able to negotiate any specific problems
faced by an individual facility with the enforcing agency. As stated in
the previous section, facilities that find the recordkeeping and measure-
ments burdensome may opt to conduct the short-term liquid balance or gas-
phase test to demonstrate compliance. In any case, the alternative
standard, use of a total enclosure and a 95 percent efficient control
device, is available to facilities that do not wish to perform the testing
and measurements associated with the capture portion of emission reduction
standard. Because EPA has determined that facilities can conduct the
measurements required for a liquid material balance and because several
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alternatives are available, the month-long liquid material balance has
been retained in the final standards.
In response to the commenter's other concern, it appears that the
commenter has misinterpreted the requirements of the gaseous emissions
compliance test. The standard requires (not assumes) that all uncon-
trolled solvent vapors will be passed through stacks suitable for
measurement. To carry out the compliance test, the source must ensure
that all VOC emissions will either be directed to the control device or be
measured at the exit stack of a temporary enclosure or at all room exhaust
points. In other words, there should be no "stray" fugitive emissions
that are not accounted for in the compliance test.
2.8.2 Plant-Wide Material Balance
Comment; One commenter (IV-D-3) recommended that the standard
include a plant-wide solvent recovery of 85 percent as an alternative
method of demonstrating compliance. The commenter stated that using a
plant-wide material balance to demonstrate compliance is justified because
1t is a simple, inexpensive, and effective method. The proposed standards
regulate some processes within a polymeric coating plant at different
levels and leave other emissions, such as those from storage, cleaning,
and transfers, unregulated. In the commenter's experience, enforcement
officers prefer methods such as a plant-wide material balance and
invariably ask for this information along with the data required by a
particular standard.
According to the commenter, a plant-wide material balance can be
easily obtained. The solvent disbursed to the plant can be readily
measured by metering solvent withdrawals from solvent tanks. Solvent
purchases, which are always measured accurately, are a direct measure of
emissions from the plant because recovered solvent is replaced into
inventory. Thus, the plant's VOC recovery efficiency can be calculated as
the difference between VOC used and VOC (including solvent) purchased,
divided by the VOC used.
Based on the fact that some emissions in the plant would be
unregulated, the commenter concluded that the proposed standards assume
and accept a plant-wide recovery of less than 93 percent. It was
suggested that EPA analyze plant-wide solvent recovery data from
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representative plants in this and related industries to determine an
appropriate recovery level under the final standard. Using several years
of data from a modern facility that nearly conforms with the proposed
standard, the commeriter concluded that a plant-wide recovery of 85 percent
would be a reasonable level for a new plant designed to comply with the
proposed standard.
Response; The option of demonstrating compliance using a plant-wide
material balance has not been incorporated into the final standards.
Section 111 of the CAA requires that the standards be based on BDT.
Compliance methods must demonstrate that the affected facility meets
standards that reflect BOT. If a plant-wide material balance were used to
demonstrate compliance for polymeric coating operations, a plant-wide
control efficiency that ensures 90 (formerly 93) percent control of VOC
emissions from the affected coating operation(s) would be required.
Without extensive testing to apportion emissions from all VOC sources in
the plant, a pi ant-wide material balance demonstrating less than
90 percent control would not ensure that the affected facility initially
achieves 90 percent control or maintains 90 percent control over each
month of operation.
It is not feasible to select a plant-wide VOC recovery value because
of the wide range of potential emission points that differ from plant to
plant. These include existing coating operations and mix equipment,
solvent storage tanks, and cleanup operations. With the variation in
emissions from such sources, it is not possible to select a single plant-
wide recovery efficiency value that would reflect BDT, yet be achievable
in all cases. Even if such a level were established, it would be
impossible to tell whether the affected facilities within the plant were
in compliance with the standards applicable to them individually. For
these reasons, a pi ant-wide material balance has not been added to the
standards as an alternative method of demonstrating compliance.
2.8.3 Carbon Adsorber Monitors
Comment; One commenter (IV-D-4) noted the unreliability and the
expense of maintaining a continuous monitoring device for a carbon
adsorber. The commenter stated that these monitors work well for short-
term measurements but are not reliable for continuous measurements because
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the high water content of the carbon adsorber exhaust immediately after
desorption damages the monitors. Thus, the industry may have difficulty
maintaining continuous monitoring over the long term as required in the
proposed regulation.
Response; The EPA must have available the means to determine whether
proper carbon adsorber operation and maintenance practices are being
carried out. The monitoring of organic compounds is the only parameter
that has been identified that adequately relates to adsorber
performance. Without these monitors, sources are unable to detect when
they may be operating out of compliance. Tests on existing systems show
that the lack of proper monitoring is a major cause of poor performance of
carbon adsorbers systems. Discussions with carbon adsorber experts
indicated that continuous monitors are available that are reliable when
the proper calibrations and maintenance procedures are used.16'17
2.9 REPORTING AND RECORDKEEPING
Comment; One commenter (IV-D-1) recommended deleting § 60.747(d),
which requires monitoring and reporting of all 3-hour periods when a
control device discharge exceeds allowable limits. The commenter stated
that reporting of monthly compliance or noncompllance based on a liquid
material balance 1s sufficient and that the 3-hour requirement places an
unwarranted burden on the facility. The commenter also stated that the
recordkeeplng needed for the monthly calculation of the VOC balance using
the formula in § 60.743(a) (as proposed) would be overwhelming.
A second commenter (IV-D-9) noted similarly that the requirement for
reporting 3-hour periods during which the average VOC concentration is
more than 20 percent greater than the average test value appears improper
when the compliance test goes beyond 3 hours (e.g., a 1-month recovery
test). The commenter suggested that a frequency requirement would be more
appropriate. The same comment applies to any other 3-hour limit that does
not adequately relate to a test exceeding 3 hours.
Response; Commenter IV-D-1 implies that an owner or operator must
comply with the requirements of § 60.747(d) as well as those of
§ 60.747(e). The observations of Commenter IV-D-9 also reflect a
misunderstanding of the requirements of the proposed standards. The
proposed standards required that either § 60.747(d) or § 60.747(e),
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depending upon the method used to demonstrate compliance, would be used to
determine reporting and recordkeeping requirements. The reportable
monitoring exceedance periods were consistent with the compliance test
periods in those cases when monitoring is required.
The final standards have been revised to attempt to avoid
misconceptions of this nature. Cross-reference tables have been added to
the standards that summarize the final standards as well as compliance,
reporting, and recordkeeping provisions.
Although the final standards allow the option of a short-term liquid
material balance, EPA believes the recordkeeping needed for the month-long
liquid material balance calculation is reasonable and not excessive. Most
companies routinely maintain records of at least some of the information
needed for the calculation, such as the amount of VOC used in the coating
operation, the amount of VOC recovered, and formulation data. Also, the
liquid material balance is used to determine compliance only when the VOC
recovery device is dedicated to a single affected coating operation. It
is anticipated that only a small number of facilities will meet the
criteria for the use of this compliance method and that most of these will
choose to demonstrate compliance by means of the alternative standard.
2.10 WORDING OF THE REGULATION
2.10.1 General Wording
Comment: One commenter (IV-0-1) recommended converting all
references to m3 to pounds. This would be consistent with the units
normally used by the industry for recordkeeping, solvent purchases, and
pollution control system and equipment specifications.
Response: Consistent with U.S. government policy, EPA has chosen the
International System of Units as the format for regulations. However, EPA
has revised all references in the final standards of m3 to Mg to be
consistent with the mass reporting basis typically used by industry and
enforcing agencies. Reporting emissions and VOC usage rates on a mass
basis rather than a volume basis also avoids the need to select average or
typical densities of materials when reporting general values.
Comment: One commenter (IV-D-1) recommended eliminating the
references to § 60.742(a)(3) (as proposed) found in § 60.744(a) (as
proposed) and §§ 60.747(b) and (c). The commenter believes that the
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wording in the latter sections, which establishes the reporting and
recordkeeping requirements for affected facilities using less than
110 m3/yr (29,059 gal/yr) (95 Mg/yr [105 tons/yr]) of VOC and for affected
facilities using at least 110 m3/yr (29,059 gal/yr) (95 Mg/yr
[105 tons/yr]) but less than 150 m3/yr (39,626 gal/yr) (130 Mg/yr
[144 tons/yr]) of VOC, is misleading. The commenter stated that, because
of the reference to § 60.742(a)(3) (as proposed), strict interpretation of
these provisions seems to require vapor-tight covers for coating mix
equipment servicing coating lines using less than 110 m3/yr
(29,059 gal/yr) (95 Mg/yr [105 tons/yr]) of VOC.
Response; References to § 60.742(a)(3) (now § 60.742(c)(3)) are made
in order to avoid repetition of affected facility classifications and
requirements. This section clearly refers to equipment serving coating
lines that use "at least 95 Mg of VOC per year but less than 130 Mg of VOC
per year."
Section 60.744(a) (now § 60.744(b)) sets forth monitoring requirements
for coating operations that utilize less than 95 Mg/yr (105 tons/yr) of VOC
and coating operations described in § 60.742(a)(3) (now § 60.742(c)(3)).
Section 60.744(a) (now § 60.744(b)) does not state that coating operations
that use less than 95 Mg/yr (105 tons/yr) of VOC are subject to the
requirements specified in § 60.742(a)(3) (now § 60.742(c)(3)).
Section 60.747(b) presents reporting and recordkeeping requirements
for coating operations described in § 60.742(a)(3) (now § 60.742(c)(3))
and coating operations that use less than 95 Mg (105 tons) of VOC in the
first year of operations. Section 60.747(c) specifies requirements for
operations described in § 60.742(a)(3) (now § 60.742(c)(3)) that initially
use less than 130 Mg/yr (144 tons/yr) of VOC and operations that initially
use less than 95 Mg/yr (105 tons/yr) of VOC. Neither section states that
coating operations that use less than 95 Mg/yr (105 tons/yr) of VOC are
subject to § 60.742(a)(3) (now § 60.742(c)(3)).
Elimination of the references to § 60.742(a)(3) (now § 60.742(c)(3))
would exclude from the monitoring, reporting, and recordkeeping require-
ments of the standards those coating operations using at least 95 Mg/yr
(105 tons/yr) but less; than 130 Mg/yr (144 tons/yr) of VOC, leaving no
means of monitoring the continued applicability of the standards for mix
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equipment in this VOC use range. Thus, the requested change has not been
made.
Comment; One commenter (IV-D-1) recommended revising the words "by
other means" to "by alternate readily available, economically feasible
means" in § 60.743(a)(l)(iv) (as proposed). Section 60.743(a)(l) sets
provisions for demonstrating that the VOC retained (RS1 in Equation 1 for
demonstrating compliance with § 60.742[a][lJ) is greater than zero.
Specifically, § 60.743(a)(l)(iv) states that the owner or operator must
submit "documentation that the inherent properties of the product require
higher levels and that such properties cannot be achieved by other
means." The commenter believes that the words "by other means" are too
comprehensive and do not take into account economic and technical
feasibility.
Response; The intent of § 60.743(a)(l)(iv) (now § 60.742(c)(3)) as
proposed was to ensure that all facilities take steps to minimize
uncontrolled emissions from retained VOC whenever possible. The exemption
for retained VOC was written to permit the facility as much flexibility as
possible in demonstrating to the Administrator the level of, and need for,
retained VOC. However, EPA has revised this requirement to minimize the
burden on both enforcement and plant personnel. The revised requirement
eliminates the need for the plant to justify the need for retained VOC if
the measured value of RS^ is less than or equal to 6 percent by weight of
the liquid VOC applied. A limited survey of the Industry indicated that
6 percent is a common breakpoint in retained VOC values and would
encompass the majority of plants reporting retained VOC.18 Plants
reporting RS1 values above 6 percent by weight of the liquid VOC applied
would still be required to demonstrate to the satisfaction of the
Administrator that the retained VOC 1s required for product quality or to
meet product specifications. In all cases, plants would be required to
submit for approval data on the specific measurement techniques used to
determine RS^.
Comment; One commenter (IV-D-9) recommended that a continuous
monitoring device (CMD) be required for a carbon adsorber that controls
just one emission source. The wording in the proposal preamble indicated
that a CMD is required when two emission sources are controlled, but not
just one.
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Response; When a source chooses to make a monthly compliance
demonstration using a liquid material balance, no monitoring of the sol-
vent recovery device is required. This compliance method is applicable
only when emissions from a single affected coating operation are recovered
by a dedicated control device. The wording in the proposal preamble was
based on the use of this compliance method. However, should such a source
choose to demonstrate compliance with the alternative standard, the
monitor appropriate for the control device in use would be required.
Comment; One commenter (IV-D-3) recommended that § 60.742(a)(l) (as
proposed) read "Reduce VOC emissions to the atmosphere by at least
93 percent, compared to an uncontrolled coating operation, from each
coating operation; and. ..." Adding the words "compared to an
uncontrolled coating operation" would eliminate any confusion that the
93 percent reduction may be compared to a controlled source before
modification or reconstruction.
Response; The intent of the emission reduction standard for coating
operations is to require that at least 90 percent (93 percent at proposal)
of the VOC content of the coating applied at the coating applicator(s) be
prevented from entering the atmosphere. The EPA believes this intent to
be clear in § 60.742(a)(l) (now § 60.742(b)(l)) as written. The
compliance provisions also make the intent of the standard clear. Deter-
mination of 90 percent control is based on all VOC 1n the coating applied
at the coating applicator(s) and not just the incremental increase in VOC
resulting from modification or reconstruction. Therefore, no changes to
the wording of the standard have been made.
Comment; One commenter (IV-D-7) noted that the allowance for
2 percent fugitive losses from nix equipment is not clearly stated in the
proposal.
Response; The standards do not make an allowance for 2 percent
fugitive losses from mix equipment. Section 60.742(a)(2) (now
§ 60.742(c)), as proposed, clearly stated that alj VOC emissions shall be
captured. However, in response to other comments, the language of the
section has been modified. A detailed explanation of the change can be
found in the response to Comment 2.4.2.
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Comment; One commenter (IV-D-9) suggested that the volumetric flow
rate be stated on a wet basis rather than a dry basis since, according to
a contact at EPA, Method 25A results in parts per million by volume on a
wet basis.
Response; The commenter is correct. Measurements made using
Method 25A are in terms of parts per million by volume on a wet basis;
therefore, the volumetric flow rate also should be stated on a wet basis
when this method is used. The final standard has been corrected to
specify that volumetric flow rates used in conjunction with Method 25A
concentration measurements are to be expressed in standard cubic meters
per hour (wet basis). However, volumetric flow rates used in conjunction
with Method 25 concentration measurements are to be expressed in dry
standard cubic meters per hour.
2.10.2 Definitions
2.10.2.1 "Coating Line".
Comment; One commenter (IV-D-9) stated that, for consistency with
other NSPS and State regulations, coating mix preparation equipment should
not be included in the definition for a coating line. The commenter
believed that the term "coating line" was unnecessary since "coating
operations" and "coating mix preparation equipment" are described. The
commenter suggested changing all references to "coating operations" to
"coating lines" since these two terms, by his definition, are synonymous.
Response; In the proposed NSPS, coating line was defined as "the
coating operation(s) and coating mix preparation equipment that service
the coating operation(s)." According to the commenter, the term coating
line is commonly used interchangeably with coating operation. To avoid
confusion, the term "coating line" is not used in the final standard. The
term "coating operation" has been retained in order to maintain consistency
with the Volume I BID and proposal preamble.
2.10.2.2 "Common Emission Control Device".
Comment; One commenter (IV-D-9) requested clarification of the
definition of "common emission control device." He stated that it was
unclear whether the proposed definition referred to a device controlling
both a coating operation and mix equipment or a device that controls two
or more coating operations.
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Response: In response to the commenter and for clarification, the
definition has been amended to read: "'Common emission control device1
means a control device controlling emissions from an affected coating
operation as well as from any other emission source." The "other emission
source" may be a coating operation(s), mix equipment, or any other point
of emissions.
2.10.2.3 "Drying Oven".
Comment; One commenter (IV-D-3) recommended eliminating references
to baking, curing, and polymerizing from the definition for drying oven.
In the commenter1s process, drying and curing are done in separate ovens.
Although the preamble makes clear that the curing oven is not covered by
the standard, the proposed definition for "drying oven" suggests that the
curing oven is included.
Response: The definition of drying oven has been changed to "a
chamber within which heat is used to dry a surface coating; drying may be
the only process or one of multiple processes performed in the chamber."
By eliminating references to baking, curing, and polymerizing, this
revised definition makes it clear that the standard does not apply to
chambers in which drying is not performed. The definition also makes it
clear that the standard does apply to any chamber within which drying is
performed, regardless of the other processes performed in the chamber.
This change is consistent with the fact that cure volatiles resulting from
separate curing ovens are expected to be minimal 1n this industry and to
occur off-site, and thus, are not available for control.
2.10.2.4 "Knife Coater".
Comment; One commenter (IV-D-9) believed that a definition of "knife
coater" would be useful. The commenter pointed out that the term "blade"
is used in the "web coating" definition.
Response: A definition of "knife coater" has not been added because
EPA believes that the term is self-explanatory. Knife coating and blade
coating were used interchangeably in the proposed regulation. To avoid
confusion, the reference to blade coating in the definition of "web
coating" has been changed to knife coating. The new definition of "web
coating" is "the coating of products, such as fabric, paper, plastic film,
metallic foil, metal coil, cord, and yarn, that are flexible enough to be
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unrolled from a large roll; coated as a continuous substrate by methods
including, but not limited to, knife coating, roll coating, dip coating,
impregnation, rotogravure, and extrusion; and, after drying, rerolled."
2.10.2.5 "Solvent".
Comment; One commenter (IV-D-2) suggested adding a definition of
"solvent" to clarify that the regulation addresses only volatile organic
liquids. The commenter stated that an increased amount of polymeric
coating is done with waterborne emulsions. Without a specific definition
for solvent, one could erroneously conclude that polymeric coating sol-
vents other than volatile organic liquids (e.g., water) are included in
the "solvent used" for purposes of determining the applicability of the
emission limits.
Response: The commenter correctly pointed out that for the purposes
of this regulation as proposed, solvent refers only to volatile organic
liquids and does not Include water. Part of the confusion resulted from
the use of the term's "VOC" and "solvent" interchangeably in the proposed
rule and supporting documents. The final rule has corrected this problem
by specifying that VOC 1s the pollutant of concern. Organic solvent is a
major component of VOC, not water. (See Section 2.10.2.6 for this
definition.)
2.10.2.6 "Solvent (VOC) Used".
Comment: One commenter (IV-D-8) recommended changing the definition
for solvent used from "the amount of solvent delivered to the coating mix
preparation equipment of the affected facility" to "the net quantity con-
sumed 1n the coating operation line." With this change, the amount of
solvent (VOC) used would represent the amount actually applied to the
substrate. According to the commenter, coating mixes are typically
prepared in greater quantities than required for a specific production
run. The excess coating may be recycled, which would result in double
counting, or disposed as a waste material.
Response; "Solvent used" was defined at proposal as the amount of
solvent delivered to the coating mix preparation equipment because
(1) this is the simplest and most direct measurement point, and (2) it
reflects the quantity used in determining the cutoff. The commenter's
suggested definition of "solvent use" would make accurate measurement
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considerably more difficult because sampling and analysis of the applied
coating would be required. Also, the commenter's suggested definition
does not take into account VOC emitted during mixing, which were included
1n the computation of the solvent-(VOC-)use cutoff. The cutoff was
computed by determining the minimum quantity of applied VOC that could be
cost-effectively controlled and then adjusting this volume to account for
VOC emitted before the coating reaches the applicator of the affected
coating operation.
The proposed definition was not intended to result in double
counting. However, it may require the owner or operator to keep careful
records of VOC use in cases where prepared coatings are not used
immediately.
To clarify the meaning of this term, the definition has been changed
to MVOC used." The amount of "VOC used" should be computed as the sum of
(1) the VOC to the mix equipment from storage, (2) any VOC added after
initial formulation 1s complete (e.g., dilution solvent added at the
coating operation), and (3) the VOC content of any Ingredients prepared
off the plant site that are used in the preparation of coatings. When
excess coating 1s recycled for use in a later coating run, the VOC it
contains should not be counted a second time. Should a source reclaim the
VOC from excess coatings, the VOC will enter the VOC recovery system just
as if it were applied to a substrate. When this reclaimed VOC 1s reused,
it will be properly counted toward the volume of VOC used. It is true
that coatings disposed as waste materials were not considered when the
annual VOC use cutoff was calculated. However, EPA believes that such
wastes should be minimized. Thus, to provide an incentive to minimize
these wastes, no change has been made to this aspect of the definition.
A change has been made to the proposed definition to account for
facilities that purchase premixed coatings or other ingredients that
contain VOC. The new definition reads "the amount of VOC delivered to the
coating mix preparation equipment of the affected facility (including any
contained 1n premixed coatings or other ingredients prepared off the plant
site). If premixed coatings that require no mixing at the plant site are
used, "VOC used" means the amount of VOC delivered to the coating
applicator(s) of the affected facility.
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2.10.2.7 "Web Coating".
Comment: One commenter (IV-D-9) questioned whether the definition of
"web coating," which states "... flexible enough to be unrolled from a
large roll; . . .; and, after drying, rerolled," should include the
requirement that the web be rerolled. The commenter pointed out that at
some facilities products are cut into strips or sheets after drying. In
addition, the commenter suggested including extrusion (i.e., the use of a
slotted die) as an application method.
Response; Taken literally, the proposed definition of "web coating"
requires only that the substrate be flexible enough to be unrolled,
coated, and rerolled, not that these operations actually be carried out.
However, to avoid confusion concerning the EPA's intent, the definition of
"coating operation" has been modified to clarify the point that no poly-
meric coating facility is to be exempt simply because it lacks a rewind
station. The definition has been changed to "any coating applicator(s),
flashoff area(s), and drying oven(s) located between a substrate unwind
station and a rewind station that coat a continuous web to produce a
substrate with a polymeric coating. Should the coating process not employ
a rewind station, the end of the coating operation is at the end of the
last drying oven in the process." In addition, the definition of web
coating has been refined to eliminate reference to rerolling.
The commenter's suggestion that extrusion be added to the list of web
coating techniques contained 1n the definition of "web coating" has been
adopted. Also, wording has been added to make 1t clear that the list of
coating techniques is not intended to be inclusive. As discussed in
Section 1.1, leather has been removed from the list of substrates. The
definition of "web coating" has been revised to "the coating of products,
such as fabric, paper, plastic film, metallic foil, metal coil, cord, and
yarn, that are flexible enough to be unrolled from a large roll; coated as
a continuous substrate by methods including, but not limited to, knife
coating, roll coating, dip coating, impregnation, rotogravure, and extru-
sion."
2.10.2.8 "Mr^.
Comment; One commenter (IV-D-8) suggested redefining the symbol Mr
used in Equation 1 as the total VOC recovered before purification. The
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proposed definition does not allow for VOC losses during separation/
purification.
Response; As proposed, the definition of "Mr" does not specify
whether the recovered VOC is to be measured before or after separation/
purification. The 93 percent recovery efficiency required to demonstrate
compliance using Equation 1 was determined considering the VOC recovered
after carbon adsorption and not after separation/purification. Therefore,
EPA cannot require measuring "Mr" after separation/purification. There
may be cases, however, where it is more convenient to measure "Mr" after
separation/purification. Thus, a measurement point for "Mr" has not been
specified, but it is to be established when the compliance procedures are
approved. This is explained in § 60.743(a)(3)(vi), which has been added
to the compliance provisions.
2.10.2.9 "RS^.
Comment; One commenter (IV-D-8) suggested redefining the term RS1 in
Equation 1 to include all VOC, not just the solvent, retained on the
substrate. A portion of the VOC 1n some coating formulations is monomer
that 1s retained in the substrate as either free monomer or polymer. The
suggested definition change would make it clear that any monomer retained
1n the substrate would be included in the term RS^.
Response; In response to the commenter's suggestion, the definition
of RSj has been changed to "the total mass (kg) of VOC retained in the
substrate after oven drying for a given combination of coating and
substrate." Without this change, coatings that release reaction by-
products when tested by Method 24 would Indicate the presence of some VOC
which may not be available for recovery by the VOC recovery system unless
the coating is exposed to a similar temperature within the oven. If the
amount of monomer retained on the substrate is significant, this may
affect a source's ability to demonstrate compliance. Changing "solvent"
to VOC in the definition of RS1 enables the source to account for the
amount of VOC retained on the substrate. The source is responsible for
demonstrating the quantity retained on the substrate.
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2.11 MODIFICATION/RECONSTRUCTION
2.11.1 Retrofitting Total Enclosures in Printing Blanket Manufacturing
Comment; One commenter (IV-D-5) stated that EPA failed to consider
the feasibility of the proposed regulation for modified facilities. The
commenter stated that, while it may be possible to develop new coating
techniques that would allow new coating equipment to be totally enclosed,
it is virtually impossible to retrofit total enclosures to existing
coating equipment in the printing blanket manufacturing industry. Citing
practical limitations, the commenter ruled out a small enclosure around
the coater, as well as the possibility of enclosing the entire coating
room. The commenter stated that the only feasible method of capturing VOC
emissions from existing printing blanket coaters is to construct a small
room enclosing the affected coating equipment. The commenter determined
that the only practical means of ensuring worker safety while implementing
this method would be to exhaust high volumes of air from the enclosure.
However, in the commenter's analysis, this would drive up the cost of
control equipment significantly and result in an unacceptably high cost
effectiveness (see Section 2.4.1).
Response; The EPA has considered the feasibility of the standards
for modified facilities. This subject was discussed both in the preamble
to the proposed standards and in the Volume I BID. It was concluded that
changes to coating operations that would be considered modifications under
the General Provisions of 40 CFR Part 60 are unlikely. In those cases
where modifications do occur, the same capture and control techniques that
can be used at new facilities can be applied at modified facilities at a
reasonable cost. However, since proposal EPA has reexamined the
feasibility of total enclosures and reached the following conclusions.2
1. Because frequent access to the application/flashoff area is
required in some segments of this industry, a small total enclosure
immediately around the application/flashoff area could not be used in all
cases.
2. A local ventilation system could be constructed in all cases that
would capture emissions from the application/flashoff area very effi-
ciently and be protective of worker health and safety at a reasonable
cost. In conjunction with an appropriately designed larger, room-type
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enclosure, the capture system would meet the total enclosure specifica-
tions added since proposal.
3. A room-type total enclosure may not be universally feasible.
Space constraints at existing plants may not allow construction of a room
to enclose a new or modified/reconstructed coating operation.
As a result of this analysis, the standards for new and modified/
reconstructed coating operations have been revised to require either a
90 percent overall emission reduction or a total enclosure and 95 percent
efficient control device (alternative standard).
The EPA does not accept the commenter's conclusion that workers
inside a room-type total enclosure cannot be protected in a cost-effective
manner. The commenter's analysis was based on the assumption that the
only way to ensure the safety of workers within the total enclosure is to
ventilate the enclosure with enough air to dilute emissions to a safe
level. However, as discussed above, localized pickups can be designed to
direct emissions away from the workers while reducing the airflow to a
level allowing cost-effective control. This issue is more fully examined
in Section 2.4.1.
2.11.2 NSPS Applicability Date
Comment; One commenter (IV-D-7) stated that compliance with the NSPS
will be required of facilities where modifications or reconstruction began
after the issuance of the proposed rule rather than upon adoption of the
final rule. In the commenter's view, this policy is onerous. The com-
menter stated that EPA has not demonstrated that control technology exists
for this industry that would comply with the proposed regulations (see
Sections 2.3.1.1, 2.3.1.3, and 2.3.2.2). Thus, companies must delay the
installation of new equipment or modification of existing equipment,
including pollution control devices, because they may not meet the final
standards. Companies that have incurred major capital expenditures to
meet State requirements would be at an even greater disadvantage if their
new control equipment fails to meet EPA's standards but is considered
subject to them.
Response; Section lll(a)(2) of the CAA requires that the
applicability date for NSPS be the date of proposal. For the polymeric
coating NSPS, the standard is applicable to affected facilities that are
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constructed, modified, or reconstructed on or after April 30, 1987. This
date could be adjusted if it were determined that BOT was not available
for use on that date. In this case, EPA believes that BDT is available
and is not aware of a technical problem that has prevented sources from
proceeding with modifications.
As discussed in the proposal preamble and Volume I BID, changes to
polymeric coating operations with associated mix equipment that would be
considered modifications under the General Provisions (40 CFR 60.14) are
expected to occur rarely, if at all. In any case, sources that installed
control equipment prior to April 30, 1987, to meet existing State require-
ments and that subsequently modify their facilities are expected only to
have to modify the capture systems at those facilities in order to comply
with the NSPS. The existing control devices will, with some operational
changes, be capable of achieving the efficiency necessary to meet the
standards. The cost to retrofit capture systems may be slightly more than
the cost of capture systems installed at the time of original construc-
tion, but this increase is not expected to be so large as to make the
costs unreasonable. The cost effectiveness for such facilities is no
different than for other existing sources at the same level of control
efficiency.
2.12 REFERENCES FOR CHAPTER 2
1. Memo from Lang,, C. and Friedman, B., Midwest Research Institute, to
Polymeric Coating project file. December 22, 1988. Affected
Facility Options for Polymeric Coating NSPS: Mix Equipment.
2. Memo from Edgerton, S., Midwest Research Institute, to Polymeric
Coating project; file. January 6, 1989. Permanent Total Enclosures
in the Polymeric Coating Industry.
3. Radian Corporation. Carbon Adsorption for the Control of VOC
Emissions: Theory and Full-Scale Performance. Prepared for U.S.
Environmental Protection Agency. Research Triangle Park, N.C.
Publication No. 88-239-003-20-09. June 6, 1988. p. 3-67.
4. Memo from Friedman, B., Midwest Research Institute, to Polymeric
Coating project file. January 6, 1989. The Effects of Batch
Operations on Control Device Performance and Costs.
5. Memo from Shine, B., and Srebro, S., Midwest Research Institute, to
Polymeric Coating project file. August 25, 1988. Cost Effectiveness
of Incinerators to Control VOC Emissions from Polymeric Coating
Operations.
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6. Memo from Friedman, B., Midwest Research Institute, to Polymeric
Coating Coating project file. December 21, 1988. Basis of the
Polymeric Coating NSPS.
7. Letter from Murphy, J., W. R. Grace & Co., to Soltls, V., Midwest
Research Institute. April 21, 1988. Comments on telephone contact
reports regarding coating operation liquid material balance test
results.
8. Telecon. Shine., B., Midwest Research Institute, with Woodcock, R.,
Day International. Effect of filters on carbon bed blinding.
9. Telecon. Soltls, V., Midwest Research Institute, with Troup, T., Dow
Corning Corp. September 11, 1987. Discussion about the performance
of an air-atmosphere condensation system.
10. VOC RACT Clearinghouse Newsletter. Vol. 2, No. 1, March 1985.
pp. 1-3.
11. Memo from Friedman, B., Midwest Research Institute, to Polymeric
Coating project file. January 6, 1989. Calculation of Allowable VOC
Content of "Waterborne" Coatings.
12. Memo to the Magnetic Tapes file. Docket A-82-45, Item IV-B-4.
December 17, 1986.
13. Memo from Edgerton, S., Midwest Research Institute, to Polymeric
Coating project file. January 6, 1989. Cost Effectiveness of Total
Enclosure at W. R. Grace plant.
14. Memorandum from Wade, J., Department of Defense, to Secretaries of
the Military Departments. July 18, 1986. Policy Guidance for VOC
Compliance Planning.
15. Frost and Sullivan, Inc., Flexible Coated and Laminated Materials and
Products Market in the United States. New York. Spring 1982.
p. 22.
16. Telecon. Hecht, D., Midwest Research Institute, with Reber, R.,
Allied Baron Blackeslee. October 15, 1987. Performance of carbon
adsorber monitors.
17. Telecon. Hecht, D., Midwest Research Institute, with Hartman, M.,
Radian Corporation. October 9, 1987. Performance of carbon adsorber
monitors.
18. Memo from Friedman, B., Midwest Research Institute, to Polymeric
Coating project file. December 8, 1988. Retained Solvent Provision.
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-450/3-85-022b
2.
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
Polymeric Coating and Supporting Substrates-Background
Information for Promulgated Standards
5. REPORT DATE
July 1989
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Office of Air Quality Planning and Standards
U. S. Environmental Protection Agency
Research Triangle Park, North Carolina 27711
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-02-3817
12. SPONSORING AGENCY NAME AND ADDRESS
DAA for Air Quality Planning and Standards
Office of Air and Radiation
U. S. Environmental Protection Agency
Research Triangle Park, North Carolina 27711
13. TYPE OF REPORT AND PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
EPA/200/04
15. SUPPLEMENTARY NOTES
16. ABSTRACT
Standards of performance for the control of VOC emissions from the polymeric
coating of supporting substrates are being promulgated under the authority of
Section 111 of the Clean Air Act. These standards apply to all new, modified, or
reconstructed polymeric coating lines using at least 95 mg/yr of VOC per year in the
production of polymeric-coated supporting substrates. This document contains a
detailed summary of the public comments on the proposed standards (52 FR 15906),
responses to these comments, and a summary of the changes to the proposed standards.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COS AT I Field/Group
Air Pollution
Pollution Control
Standards of Performance
Volatile Organic Compounds
Web Coating
Polymeric Coating of Supporting Substrates
Air Pollution Control
13B
18. DISTRIBUTION STATEMENT
Unlimited
19. SECURITY CLASS (TIlis Report)
Unclassified
21. NO. OF PAGES
76
20. SECURITY CLASS (This page)
Unclassifed
22. PRICE
EPA Form 2220-1 (R«v. 4-77) PREVIOUS EDITION is OBSOLETE
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