EP/-453/R-94-G71.
                                   DEC  51994
                  United States
                  Environmental Protection
                  Agency
Office of Air Quality
Planning and Standards
Research Triangle Park NC 27711
EPA-453/R-94-071
November 1994
                  Air
          ERA     National Emission
                  Standards for Hazardous
                  Air Pollutants:
                  Halogenated Solvent
                  Cleaning- Background
                  Information for Final Standards

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                                    EPA-453/R-94-071
         NATIONAL  EMISSION STANDARDS
        FOR HAZARDOUS AIR POLLUTANTS
       HALOGENATED SOLVENT CLEANING -
         BACKGROUND INFORMATION FOR
               FINAL  STANDARDS
  Summary of Public Comments and Responses
         Emission  Standards Division
    U.S. Environmental Protection Agency
         Office  of Air and Radiation
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711
              November 8, 1994

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                       TABLE OF CONTENTS

                                                          Page


1.0  SUMMARY	   1-1

1.1  SUMMARY OF CHANGES SINCE PROPOSAL  	   1-1

1.2  SUMMARY OF IMPACTS OF PROMULGATED ACTION 	   1-4

2.0  SUMMARY OF PUBLIC COMMENTS .    	   2-1

2.1  SELECTION OF POLLUTANTS AND SOURCE CATEGORIES FOR
     REGULATION	2-11
     2.1.1  Pollutants	2-11
     2.1.2  Halogenated Solvent Cleaning Machines ....  2-16

2.2  EMISSION CONTROL OPTIONS 	  2-25
     2.2.1  Solvent Cleaning Machine Control Technologies  2-25
          2.2.1.1  General  	  2-25
          2.2.1.2  Freeboard refrigeration devices  .  .  .  2-25
          2.2.1.3  Cover  	  2-28
          2.2.1.4  Reduced room draft 	  2-29
          2.2.1.5  Lip exhaust	2-33
          2.2.1.6  Carbon adsorber  	  2-36
          2.2.1.7  Automated parts handling system  .  .  .  2-38
          2.2.1.8  Super-heated vapor 	  2-40
          2.2.1.9  Increased freeboard height 	  2-43
          2.2.1.10 Dwell time	2-44
          2.2.1.11 Sump cool-down coils 	  2-45
          2.2.1.12 Waterlayer (cold cleaning machines)  .  2-46
     2.2.2  Control Combinations  	  2-47
          2.2.2.1  Biparting cover and reduced room draft  2-49
          2.2.2.2  Super-heated vapor and freeboard
                   refrigeration devices  	  2-50
          2.2.2.3  Freeboard refrigeration device and
                   primary cooling coils  	  2-51
     2.2.3  Alternative Cleaning Technologies 	  2-52
     2.2.4  New Technologies	2-57
     2.2.5  Fugitive Emission Controls  	  2-59

2.3  REGULATORY ALTERNATIVES  	  2-60
     2.3.1  MACT Floor	2-61
     2.3.2  MACT Versus GACT	2-64
     2.3.3  Regulatory Alternatives 	  2-67
          2.3.3.1  Emission estimates 	  2-68
          2.3.3.2  National costs 	  2-69
          2.3.3.3  Number of cleaning machines  	  2-69
          2.3.3.4  Energy impacts 	  2-70
          2.3.3.5  Environmental impacts  	  2-70

2.4  BENEFITS ANALYSIS/ECONOMICS  	  2-73
                              11

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                 TABLE OF CONTENTS (Continued)

                                                          Page

2.5  PROPOSED STANDARDS 	  2-78
     2.5.1  Equipment Standards 	  2-82
     2.5.2  Idling Standards  	  2-86
     2.5.3  Work Practices	2-97
          2.5.3.1  Operator test	2-97
          2.5.3.2  Other work practices 	   2-101
     2.5.4  Overall Solvent Emission Limit Standard .  .   2-102

2.6  MODIFICATION AND RECONSTRUCTION CONSIDERATIONS .  .   2-115

2.7  MONITORING REQUIREMENTS  	   2-116

2.8  RECORDKEEPING AND REPORTING REQUIREMENTS 	   2-123
     2.8.1  General	   2-123
     2.8.2  General Provisions  	   2-134
     2.8.3  Solvent Consumption 	   2-137
     2.8.4  Exceedance Report 	   2-137

2.9  OPERATING PERMIT PROGRAM 	   2-139

2.10 CLARIFICATIONS	   2-141
     2.10.1  Definitions  	   2-141
     2.10.2  Toxicity	   2-145
     2.10.3  Wording of Regulation  	   2-147
     2.10.4  Other	 . . .	   2-150

2.11 MISCELLANEOUS	   2-152
     2.11.1  Guidance Documents 	   2-152
     2.11.2  Compliance 	   2-154
     2.11.3  Organization 	   2-156
     2.11.4  Other	   2-157
                              ill

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                         1.0  SUMMARY

     On November 29, 1993,  the Environmental Protection Agency
(EPA) proposed national emission standards for hazardous air
pollutants (NESHAP) for halogenated solvent cleaning
(58 FR 62566) under authority of section 112 of the Clean Air
Act (Act).  Public comments were requested on the proposal in
the Federal Register.  There were 57 commenters composed
mainly of States, solvent cleaning machine users, solvent
cleaning machine vendors, and industry trade associations.
     All of 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
     A.  Significant Changes
     Several changes have been made since the proposal of
these standards.  The majority of the changes have been made
to clarify portions of the rule that were unclear to the
commenters.  Other changes include adding additional control
combinations, reducing the monitoring frequencies, extending
reporting deadlines, extending the compliance period, and
adding an equation that allows cleaning machines that do not
have a solvent vapor/air interface area to comply with the
standard by meeting a solvent emission limit based on cleaning
capacity.  A summary of the major changes is presented below.
     (1)  Several comments were made about the complexity of
the rule, with many commenters offering suggested changes to
clarify different sections.   Many of these recommendations
have been incorporated into the final rule.  For example, the
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standards for batch cold cleaning machines have been moved to
a separate section, the operator test has been included as
appendix B, and a table summarizing the applicability of the
General Provisions to this rule has been included in
appendix C.
     (2)  The applicability section of the rule has been
clarified to ensure that the standard regulates only those
solvents originally intended for inclusion; namely, methylene
chloride (MC), perchloroetylene (PCE),
1,1,1-trichloroethane (TCA), trichloroethylene (TCE),
chloroform (C), and carbon tetrachloride (CT).  Throughout the
rest of this document, the term "halogenated HAP solvent,"
refers solely to these 6 solvents.  Several commenters were
concerned that, as proposed, the rule could be interpreted to
regulate non-halogenated solvents contaminated by trace
amounts of halogenated solvent.  The EPA never intended for
these solvents to be included in these standards.
     (3)  An equation has been added to the final rule to
allow solvent cleaning machines that do not have a solvent
vapor/air interface area to comply with these standards.
Several new cleaning machines are currently being developed by
industry that cannot install the equipment control devices
included in this final rule, do not have an idling mode, and
do not have a solvent vapor/air interface area to relate to
the solvent emission limit.  The equation and table in the
rule allow owners or operators of halogenated solvent cleaning
machines without a solvent vapor/air interface area to comply
with the standard by meeting a solvent emission limit based on
cleaning capacity that is equivalent to the overall solvent
emission limit for machines with a solvent vapor/air
interface.
     (4)  The list of equipment combinations has been modified
to remove overlapping controls and to add carbon adsorbers to
the control combinations.  There are multiple control
combinations  available for meeting the rule, many of which are
pollution prevention measures.  Many of these options also

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reduce worker exposure.  However, some sources may rely on lip
exhausts instead in order to meet OSHA requirements.  Use of a
lip exhaust without any controls, while reducing worker
exposure on the one hand, would dramatically increase the
overall emissions to air.  Thus, if lip exhausts are used on
solvent cleaning machines, the rule requires carbon adsorption
controls (which have been added explicitly as a control option
in the final rule).  Although the lip exhaust-carbon
adsorption combination reduces worker exposure and overall
emissions to air, it may impose additional cost and burden on
sources as well as on the environment for a number of reasons.
First, carbon adsorption units are generally more expensive
than other controls listed in the options.  Second, these
units may present cross-media impacts such as effluent
discharges if not properly operated and maintained, and spent
carbon beds that have to be disposed of as hazardous waste.
Thus, when making decisions about what controls to install on
halogenated solvent cleaning machines to meet the requirements
of this rule, all of these factors should be weighed and
pollution prevention measures are encouraged wherever
possible.
     The EPA acknowledges that data show little additional
emission reduction by the use of a working-mode cover in the
presence of reduced room draft  (RRD).  Therefore, these
controls are no longer included in the same control
combination.
      (5)  Some changes have also been made to the compliance
and reporting schedules.  The initial notification report
deadline for existing sources has been extended from 90 to 270
days after promulgation.  This overrides the 120 day deadline
in the final part 63 General Provisions.  The initial
statement of compliance report deadline for new and existing
sources has been extended from 30 days to 150 days after the
compliance date to allow time for owners or operators to
determine compliance with the 3-month rolling average emission
limit.  This is consistent with the General Provisions.  The

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compliance time for existing sources has been extended from 2
to 3 years.  This extension has been provided to allow sources
the maximum flexibility in complying with these standards,
including allowing time to consider alternative cleaning
technologies.  This change is consistent with the General
Provisions [§ 63.6(b)(3)].  The exceedance report schedule has
been changed to include a biannual exceedance report if there
is not an exceedance.  This change is consistent with the
General Provisions[§ 63.10(e)].
     (6)  Several commenters stated that the rule was complex
and difficult to understand.  They stated that additional
guidance should be provided, particularly for small
businesses.  The EPA agrees that additional guidance would be
helpful and has developed a brochure summarizing the rule, and
will be developing a guidance manual that is scheduled for
publication in early 1995.  This guidance manual will include
a detailed summary of the rule, example forms that can be used
for reporting and recordkeeping, and additional assistance for
evaluating alternative cleaning technologies.
     (7)  Several commenters recommended that the EPA reduce
the monitoring frequency of the emission control equipment.
The EPA evaluated the monitoring frequencies and has added a
provision to the final rule that allows the hoist monitoring
frequency to decrease from monthly to quarterly if, the owner
or operator has operated the hoist for one year without an
exceedance in the hoist speed.  The EPA has also changed the
reduced room draft (RRD) monitoring frequency from weekly to
quarterly with weekly monitoring of the parameters used to
obtain the PJ*D.
     (8)  Several comments were received on the batch cold
cleaning machine equipment requirement provisions.  A number
of commenters reported the use of TCA, MC, and TCE in
noncarburetor batch cold cleaning machine operations.  The
commenters stated that the proposed water layer control option
was not always possible for these cleaning machines,
particularly when TCA or TCE solvents are used.  In order to

                              1-4

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address this issue, alternative control equipment options were
added to the final rule to allow for the use of an increased
freeboard ratio and cover, or remote-reservoir and cover, in
lieu of a water layer and cover.  Owners or operators
complying with these alternative options must comply with work
practice requirements.  The final rule also allows an owner or
operator of a batch cold cleaning machine to use alternative
control equipment, if demonstrated to be equivalent to the
equipment requirements cited in the final rule and approved by
the Administrator.
     (9)  Several commenters requested revisions to the
proposal preamble.  The EPA does not revise proposal preambles
but issues a promulgation preamble that does not include the
background information presented at proposal.  Any
clarifications or requests for changes made by commenters are
therefore addressed in this document.
1.2  SUMMARY OF IMPACTS OF PROMULGATED ACTION
     These standards will reduce nationwide emissions of
hazardous air pollutants (HAP) from halogenated solvent
cleaning machines by 77,400 Mg/yr (85,300 tons per year), or
61 percent in 1997 compared to the emissions that would result
in the absence of the standards.  No adverse secondary air
impacts, water, or solid waste impacts are anticipated from
the promulgation of these standards.
     The national annual energy usage due to the installation
of the required control devices is expected to increase from
12.9 million KWH/yr to 66.9 million KWH/yr, which is
equivalent to approximately 29.3 thousand barrels of oil.
     The implementation of this regulation is expected to
result in an overall annual national net savings of
$19 million.  This includes a net annualized savings from
installation of control devices of $30.5 million and a total
monitoring, reporting, and recordkeeping cost of
$11.6 million.  These savings will come from the significant
decrease in solvent emissions and, therefore, solvent
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consumption,  which outweigh the overall cost of air pollution
control equipment and monitoring and recordkeeping costs.
     The economic impact analysis has not been revised for
promulgation because the changes in costs are not expected to
have any effect on the results of the analysis.  While the
estimated annual costs for the regulation have increased since
proposal, there are still cost savings for most affected
entities.  Only entities with small or medium-sized cleaning
machines will not have cost savings, and the costs for the
selected regulatory alternatives for these entities have
changed very little since proposal.  Since those entities that
do not have cost savings were the only ones analyzed in the
proposal, and these costs have changed little, the results
from the economic impact analysis at proposal should still
hold for promulgation.
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                2.0  SUMMARY OF PUBLIC COMMENTS

     A total of 57 letters commenting on the proposed
standards and the background information document (BID) for
the proposed standards were received.  Since no one requested
a public hearing on the proposed standards, no public hearing
was held.  A list of the commenters, their affiliations, and
the EPA docket number assigned to their correspondence is
given in table 2-1.
     For the purpose of orderly presentation, the comments
have been categorized under the following topics:
     •    Selection of pollutants and source categories for
          regulation.
     •    Emission control options.
     •    Regulatory alternatives.
     •    Benefits analysis/economics.
     •    Proposed standards.
     •    Modification and reconstruction considerations.
     •    Monitoring requirements.
     •    Recordkeeping and reporting requirements.
     •    Operating permit program.
     •    Clarifications.
     •    Miscellaneous.
                              2-1

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         TABLE 2-1.  LIST  OF  COMMENTERS ON PROPOSED
        NATIONAL EMISSION  STANDARD  FOR HAZARDOUS AIR
              POLLUTANTS FOR  SOURCE CATEGORIES:
                HALOGENATED SOLVENT CLEANERS


 Docket numbera'b	Comroenter and affiliation

 IV-D-Ol             Mr. Frank Penque, Jr.
                    Industrial Engineer
                    Greif Bros. Corporation
                    501 John James Audubon Parkway
                    Amherst, New York  14228


 IV-D-02             Mr. Courtney Garland,  P.E.
                    State of Arkansas
                    Department of Pollution Control
                      and Ecology, Air Division
                    8001 National Drive
                    Little Rock, Arkansas  72219-8913

 IV-D-03             Ms. Katy Wolf, Ph.D.
                    Executive Director
                    Institute for Research and
                      Technical Assistance
                    2800 Olympic Boulevard, Suite 101
                    Santa Monica, California  90404

 IV-D-04             Mr. Keith Duval
                    Manager, Rule Development Section
                    Ventura County Air Pollution
                      Control District
                    702 County Square Drive
                    Ventura, California  93003

 IV-D-05             Mr. Peter T. E. Gebhard, III
                    President
                    SEREC Corporation
                    Post Office Box 28129
                    Providence, Rhode Island  02908

 IV-D-06             Mr. I. N. Vaughan
                    Manager
                    City of Huntsville
                    Division of Natural Resources
                    305 Church Street
                    Huntsville, Alabama  35801

 IV-D-07             Mr. Bill Lanier
                    Bowden Industries
                    1004 Oster Drive, N.W.
	  	 Huntsville, Alabama  35816	
                              2-2

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         TABLE  2-1.  LIST OF COMMENTERS ON PROPOSED
        NATIONAL EMISSION STANDARD FOR HAZARDOUS AIR
              POLLUTANTS FOR SOURCE CATEGORIES:
                HALOGENATED SOLVENT CLEANERS
                         (CONTINUED)


 Docket numbera>k	Commenter and affiliation	

 IV-D-08             MS. Catherine R.  M.  Ehlhardt
                    Senior Project Engineer
                    Environmental Affairs Division
                    Eli Lilly and Company
                    Lilly Corporate Center
                    Indianapolis, Indiana  46285

 IV-D-09             Mr. John W. Walton,  P.E.
                    State of Tennessee
                    Department of Environment and Conservation
                    401 Church Street, 9th Floor L & C Annex
                    Nashville,  Tennessee  37243-1531

 IV-D-10             Mr. Peter E. Voytek,  Ph.D.
                    Vice-President
                    Halogenated Solvents Industry Alliance
                    2001 L Street, N.W.,  Suite 506
                    Washington, D.C.   20036

 IV-D-11             J.  Ohlmann, P.E.
                    Corporate Environmental Technology
                      and Compliance
                    Grumman Corporation
                    Mail Stop:  D08-GHQ
                    Bethpage,  New York  11714-3580

 IV-D-12             Mr. Ferd.  J. Chmielnicki
                    Detrex Corporation
                    Post Office Box 5111
                    Southfield, Michigan  48086-5111

 IV-D-13             Mr. Gerald W. Lancour, Director
                    Safety,  Health and Environmental
                      Affairs-MDC
                    McDonnell Douglas
                    Post Office Box 516
                    Saint Louis, Missouri  63166-0516

 IV-D-14             Mr. Desi M. Chari
                    Environmental Affairs Program Manager
                    Safety-Kleen
                    1000 North Randall Road
	Elgin,  Illinois  60123-7857	
                             2-3

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         TABLE 2-1.  LIST OF  COMMENTERS ON PROPOSED
        NATIONAL EMISSION STANDARD  FOR HAZARDOUS AIR
              POLLUTANTS FOR  SOURCE CATEGORIES:
                HALOGENATED SOLVENT CLEANERS
                          (CONTINUED)


 Docket numbera>k	Commenter and affiliation	

 IV-D-15             Mr. Charles D. Malloch
                    Director,  Regulatory Management
                    Monsanto Company
                    800 North Lindbergh Boulevard
                    St. Louis, Missouri  63167

 IV-D-16             Mr. B. C.  Carmine, P.E.
                    Manager,  Air Resources Division
                    The Light Company
                    Houston Lighting and Power
                    Post Office Box 1700
                    Houston,  Texas  77251-1700

 IV-D-17           .  Mr. J. H.  O'Brien
                    Staff Vice President
                    Environmental Affairs
                    Lockheed Corporation
                    4500 Park Granada Boulevard
                    Calabasas, California  91399-0330

 IV-D-18             Mr. Wayne H. Jochmann
                    Aluminum Company of America
                    Post Office Box 3567
                    Davenport, Iowa 52808

 IV-D-19             Mr. Robert W. Schenker
                    General Electric Company
                    Corporate Environmental Programs
                    3135 Easton Turnpike
                    Fairfield, Connecticut  06431

 IV-D-20             Mr. Donald Theiler
                    Mr. Robert Colby
                    STAPPA/ALAPCO
                    444 North Capitol Street, N.W.
                    Washington, D.C.  20001

 IV-D-21             Mr. Robert P. Stricter
                    Chairman,  Air Toxics Subcommittee
                    The Coalition for Clean Air Implementation
                    607 Fourteenth  Street, NW., Suite 800
	Washington, D.  C.  20005-2011	
                              2-4

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          TABLE 2-1.   LIST  OF  COMMENTERS  ON  PROPOSED
         NATIONAL EMISSION  STANDARD  FOR HAZARDOUS AIR
               POLLUTANTS FOR  SOURCE CATEGORIES:
                 HALOGENATED SOLVENT CLEANERS
                          (CONTINUED)


  Docket  numbera>b	Commenter and  affiliation	

 IV-D-22             Billie J.  McGarvey
                    Facilities Engineering Division
                    National Aeronautics and Space
                      Administration Headquarters
                    Washington, D.C.  20546-0001

 IV-D-23             Mr. Paul J. Yaroschak
                    Department of the Navy
                    Office of the Assistant Secretary
                    (Installations and Environment)
                    Washington, D.C.  20360-5000

 IV-D-24             Mr. Douglas I. Greenhaus
                    National Automobile Dealers Association
                    8400 Westpart Drive
                    McLean, Virginia  22102

 IV-D-25             Ms. Natalie Zlotin
                    Air Pollution Control District
                    County of San Diego
                    9150 Chesapeake Drive
                    San Diego, California  92123-1096

 IV-D-26             Mr. John F. Feeley
                    Director of Environmental Affairs
                    Risdon Corporation
                    One Risdon Street
                    Naugatuck, Connecticut  06770

 IV-D-27             Ms. Barbara H. Morin
                    Department of Environmental Management
                    Division of Air Resources
                    State of Rhode Island and Providence
                      Plantations
                    291 Promenade Street
                    Providence, Rhode Island  02908-5767

 IV-D-28             Mr. Brian L. Taranto
                    Exxon Chemical Americas
                    Environmental Affairs Department
                    Post Office Box 3272
	Houston,  Texas  77253-3272	
                             2-5

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         TABLE 2-1.  LIST OF COMMENTERS ON PROPOSED
        NATIONAL EMISSION STANDARD FOR HAZARDOUS AIR
              POLLUTANTS FOR SOURCE CATEGORIES:
                HALOGENATED SOLVENT CLEANERS
                          (CONTINUED)


 Docket numbera'b	Commenter and affiliation	

 IV-D-29             Ms. Margaret L.  Corbin
                    Air Pollution Engineer
                    Puget Sound Air Pollution Control Agency
                    110 Union Street,  Suite 500
                    Seattle, Washington  98101-2038

 IV-D-30             Ms. Lisa J. Thorvig
                    Minnesota Pollution Control Agency
                    Air Quality Division
                    520 Lafayette Road,  North
                    St. Paul,  Minnesota  55155-4194

 IV-D-31             Mr. Toby A. Threet
                    The Dow Chemical Company
                    Legal Department
                    2030 Dow Center
                    Midland, Michigan  48674-2030

 IV-D-32             Ms. Linda J. Liszewski
                    Manager Environmental Issues
                    Eastman Kodak Company
                    343 State Street
                    Rochester,  New York  14650

 IV-D-33             Mr. Michael J. Bradley
                    Executive Director
                    Northeast States for Coordinated
                      Air Use Management
                    129 Portland Street
                    Boston,  Massachusetts  02114

 IV-D-34             Mr. Marty Olberding
                    Vulcan Chemicals
                    Technical and Environmental Services
                    Post Office Box 530390
                    Birmingham, Alabama  35253-0390

 IV-D-35             Mi. William O'Sullivan, P.E.
                    State of New Jersey Department of
                      Environmental Protection and
                      Energy>  CN 027
                    Air Quality Regulation Program
	  Trenton, New Jersey  08625-0027	
                              2-6

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         TABLE  2-1.   LIST OF COMMENTERS ON PROPOSED
        NATIONAL  EMISSION STANDARD  FOR HAZARDOUS AIR
              POLLUTANTS FOR SOURCE CATEGORIES:
                HALOGENATED SOLVENT CLEANERS
                          (CONTINUED)


 Docket number3 '*>	Commenter and affiliation	

 IV-D-36             R. W.  Curtis
                    Specialist Engineering
                    American Airlines, Maintenance
                      and Engineering Center
                    Post Office Box 582809
                    Tulsa,  Oklahoma  74158-2809

 IV-D-37             Mr. Richard K. Ketler
                    Senior Attorney
                    Air Transport Association of America
                    1301 Pennsylvania Avenue,  N.W.
                    Suite 1100
                    Washington, D.C.  20004-1707

 IV-D-38             Mr. Edward Cruthcley
                    Henlopen Manufacturing Co., Inc.
                    Valley Buffing Division
                    401 Park Road
                    Watertown,  Connecticut  06795

 IV-D-39             Ms. Julia A. Hatcher
                    Latham and Watkins
                    [on behalf of the American Electronics
                      Association]
                    1001 Pennsylvania Avenue,  N.W.
                    Suite 1300
                    Washington, D.C.  20004

 IV-D-40             Mr. Steve Risotto
                    Center for Emissions Control
                    2000 L Street, Northwest,  Suite 730
                    Washington, D. C.   20036

 IV-D-41             Mr. Benjamin W. Shaw
                    South Coast Air Quality Management District
                    21865 East Copley Drive
                    Diamond Bar, California  91765-4182

 IV-D-42             Mr. Brian Bateman
                    Bay Area Air Quality Management District
                    Toxics Evaluation Section
                    939 Ellis Street
	San Francisco, California  94109	
                              2-7

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         TABLE 2-1.  LIST OF  COMMENTERS ON PROPOSED
        NATIONAL EMISSION STANDARD  FOR HAZARDOUS AIR
              POLLUTANTS FOR  SOURCE CATEGORIES:
                HALOGENATED SOLVENT CLEANERS
                         (CONTINUED)


 Docket number5>b	Commenter and affiliation

 IV-D-43             Mr. Michael I. Dougherty
                    3M Specialty Chemicals Division
                    Environmental and Regulatory Affairs
                    1101 Fifteenth Street, N.W.
                    Washington, D.C.  20005

 IV-D-44             Mr. Philip J. Ostrowski
                    Occidental Chemical Corporation
                    Post Office Box 344
                    Niagara Falls, New York  14302-0344

 IV-D-45             Mr. Kenneth G. Ford,  P.E.
                    Thiokol Corporation
                    2475 Washington Boulevard
                    Ogden,  Utah  84401-2398

 IV-D-46             Mr. Mark T. Chiado
                    Sundstrand Corporation
                    Post Office Box 7003
                    Rockford, Illinois  61125-7003

 IV-D-47             Mr. Samuel B. Nelson
                    Richter Precision Incorporated
                    Post Office Box 159
                    East Petersburg, Pennsylvania  17520

 IV-D-48             Ms. Connie Ericson
                    Manager, Regulatory Affairs
                    Mitchell Energy & Development Corp.
                    Post Office Box 4000
                    The Woodlands, Texas 77387-4000

 IV-D-49             Mr. Thomas M. Allen
                    Division of Air Resources
                    New York State Department of
                      Environmental Conservation
                    50 Wolf Road
                    Albany, New York  12233

 IV-D-50             Win Sabatka
                    President
                    Finishing Equipment Inc.
                    3640 Kennebec Drive
	            	 St. Paul, Minnesota  55122	
                              2-8

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          TABLE  2-1.   LIST  OF  COMMENTERS ON  PROPOSED
        NATIONAL  EMISSION  STANDARD  FOR HAZARDOUS AIR
              POLLUTANTS FOR  SOURCE CATEGORIES:
                HALOGENATED SOLVENT CLEANERS
                          (CONTINUED)


 Docket number3'*3	Commenter and  affiliation	

 IV-D-51             Ms. Hannah Kimball
                    Manager,  Environmental Policy
                      and Operations
                    The Boeing Company
                    Post Office Box 3707
                    Seattle,  Washington  98124-2207

 IV-D-52             Billie J.  McGaryey
                    Director,  Facilities Engineering Division
                    National Aeronautics and Space
                      Administration Headquarters
                    Washington, DC  20546-0001

 IV-D-53             Mr. John Yavorsky, Ph.D.,  P.E.
                    Ambient Engineering Inc.
                    [on behalf of National Manufacturing
                      Company, Inc.]
                    180 Highway 34
                    Matawan,  New Jersey  07747

 IV-D-54             Mr. Raymond F. Pelletier
                    Director
                    Office of Environmental Guidance
                    Department of Energy
                    Washington, DC  20585

 IV-D-55             Mr. Joe J. Mayhew
                    Assistant Vice-President
                    Environmental and Policy Analysis
                    Chemical Manufacturers Association
                    2501 M Street, NW
                    Washington, DC  20037
 IV-D-56             Mr. Bob Olson
                    Corporate Sales Manager
                    Finishing Equipment Inc.
                    3640 Kennebec Drive
	St. Paul,  Minnesota  55122	
                             2-9

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          TABLE 2-1.   LIST OF COMMENTERS ON PROPOSED
         NATIONAL EMISSION STANDARD FOR HAZARDOUS AIR
               POLLUTANTS FOR SOURCE CATEGORIES:
                 HALOGENATED SOLVENT CLEANERS
                          (CONCLUDED)
  Docket number3
          Commenter  and  affiliation
 IV-D-60
Ms. Linda J. Liszewski
Eastman Kodak Company
343 State Street
Rochester, New York  14650
aThe docket number for the Halogenated Solvent Cleaners
 docket is A-92-39.
^Docket items IV-D-57, IV-D-58, and IV-D-59 are not comments
 specifically related to this rule.
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2.1  SELECTION OF POLLUTANTS AND SOURCE CATEGORIES FOR
     REGULATION
     Comment;   One commenter (IV-D-42) stated that it was
unclear why wipe cleaning operations were excluded from the
proposed NESHAP.  The commenter recommended that some minimum
handling, storage, and recordkeeping requirements for these
operations be included in the proposed regulation.  However,
the commenter felt that these operations should be exempt from
title V permits and the General Provisions.
     Response:  The EPA listed halogenated solvent cleaning
machines as the source category to regulate based on the
available data on these operations.   ("Documentation for
Developing the Initial Source Category List,11
EPA-450/3-91-030, July 1992.)  There was insufficient data to
support the inclusion of wipe cleaning operations.  Therefore,
these sources were not included in the NESHAP evaluation.
     Wipe cleaning operations might be listed as an HAP area
source as a result of an urban air toxics study currently
being conducted by the EPA.  If the category is listed,
standards will be evaluated for these sources including
required handling, storage, and recordkeeping requirements.
     An alternative control technology document (ACT) for VOC
emissions was developed by the EPA to address industrial
cleaning solvents, including wipe cleaning operations.  This
document EPA-453/R-94-015, finalized in February 1994,
summarizes a potential approach to identify and manage the
emissions from these operations.
2.1.1  Pollutants
     Comment:   Several commenters  (IV-D-08; IV-D-10; IV-D-21;
IV-D-28; IV-D-31; IV-D-32; IV-D-39; IV-D-43; IV-D-55) stated
that the applicability and designation of source section
(§ 63.460) of the proposed rule is unclear.  They felt the
wording might be misconstrued to cover halogenated solvents
not intended by the EPA.
     Several commenters (IV-D-08; IV-D-10; IV-D-21; IV-D-31;
IV-D-32; IV-D-55) stated that the EPA should clarify this

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ambiguity by limiting the applicability of the regulation to
methylene chloride (MC), perchloroethylene (PCE),
1,1,1-trichloroethane  (TCA), trichloroethylene  (TCE),
chloroform (CF), and carbon tetrachloride  (CT).
     Two commenters (IV-D-08; IV-D-10) stated that the rule
should only apply to the solvents listed because the EPA's
analysis was done on only 4 solvents.  One commenter (IV-D-08)
stated that the 4 halogenated solvents included in the
analysis and other covered solvents may have very different
properties.  If other solvents are included, the commenter
(IV-D-08) recommended that the EPA make separate MACT or GACT
determinations for them.  Another commenter  (IV-D-40) stated
that they did not know of any companies that currently use CT
or CF for solvent cleaning, whereas the preamble implies that
they are used to a "limited extent."
     Several commenters  (IV-D-06; IV-D-20; IV-D-28)
recommended that it be clarified that the NESHAP applies only
to cleaning machines that use halogenated solvents that are
hazardous air pollutants (HAP's) under section  112(k).
     Response:  The applicability section of the rule has been
clarified to reflect the intent of the halogenated solvent
cleaning NESHAP,  The NESHAP regulates each  individual batch
vapor, in-line vapor,  in-line cold, and batch cold solvent
cleaning machine that uses any solvent containing MC, PCE,
TCE, TCA, CT, or C, or any combination of these halogenated
HAP solvents, in a total concentration greater  than 5 percent
by weight, as a cleaning and/or drying agent.   The analysis
was based on MC, PCE, TCA, and TCE because these solvents are
the predominant halogenated HAP solvents used in these
cleaning machines.  Because these solvents are  the predominant
halogenated HAP solvents used in these cleaning machines, the
EPA believes that the  control and cost evaluation based on
these solvents is representative of the entire  category.
Although currently CT, C, and other halogenated HAP solvents
are not typically used in these cleaning machines, provisions
are included in the NESHAP to ensure that adequate controls

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are in-place if they are used.  No separate analysis or MACT
determination is required for these other halogenated HAP
solvents because the chosen MACT level of control would not
differ.
     The EPA has added a minimum total solvent content
concentration of 5 percent by weight.  By this definition, a
solvent cleaning machine must use a solvent that contains at
least 5 percent of halogenated HAP solvents by weight, in
order to be a regulated source under this NESHAP.  This level
was established to ensure that the standard does not apply to
those cleaning machines that use recycled solvents, such as
napthas or Stoddard solvents, that may have been contaminated
with halogenated compounds.  These solvents were never
intended to be included in this NESHAP.
     Comment;   Many commenters (IV-D-14; IV-D-15; IV-D-19;
IV-D-21; IV-D-28; IV-D-31; IV-D-32; IV-D-39; IV-D-40; IV-D-48;
IV-D-55) stated that the EPA should set a de minimis level for
the halogenated solvent content of the solvents.  The
recommended de minimis levels ranged from trace quantities to
a level of 5 percent.
     One commenter (IV-D-32) stated that the term "blend" used
in S 63.460 allows no latitude to accommodate situations where
a solvent mixture may contain a very small, even trace amount
of halogenated solvent.  The commenter maintained that this
situation can easily occur as a result of cross-contamination
when different types of solvent cleaners are used on the same
parts or as the result of shared conveyance systems.  The
commenter warned that solvent mixtures that are not the focus
of this standard, such as those that contain Stoddard
solvents, may be pulled into the regulation.  The commenters
suggested that solvents with a halogenated solvent content
below the de minimis level would not be considered halogenated
solvents and therefore would be exempt from the rule.  Another
commenter (IV-D-21)  stated that the EPA should limit the rule
only to those 6 solvents so that any listed detectable HAP
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that may be found in a solvent as a contaminant would not be
construed as a blend using a halogenated solvent as a cleaning
solvent.
     One commenter (IV-D-14) supplied an example exemption
that was cited in the context of the Ozone-Depleting
Substances (ODS) labeling rule which specifically excludes
products in which trace quantities of a controlled substance
remain as a residue or impurity due to a chemical reaction,
and where the controlled substance serves no useful purpose in
or for the product itself from regulation.  The commenter
stated that if the EPA does not make this clarification, many
of their customers will require that only virgin solvent be
supplied for their parts washers and they will have to dispose
of the waste solvent instead of recycling it.
     Another commenter (IV-D-21) requested that a de minimis
threshold level be established for each identified chemical.
The commenter strongly recommended that any established de
minimis level should be no more stringent than those required
by law to be reported by chemical manufacturers.  Two
commenters (IV-D-15; IV-D-21) stated that the reportable
thresholds are prescribed by the Occupational Safety and
Health Act (OSHA) 1910.1200 - Hazard Communication Standard,
which establishes a one percent (1 percent) ingredient
disclosure limit for non-carcinogens and a one-tenth percent
(0.1 percent) limit for suspected carcinogens.
     Three commenters  (IV-D-28; IV-D-39; IV-D-55) recommended
that the level be at least 1 percent halogenated HAP's.  One
commenter  (IV-D-55) stated that this level is necessary to
account for impurities in solvents used as replacements for
halogenated solvents.  The commenter stated that these
replacement solvents may contain 0 to 1 percent halogenated
HAP's as impurities.
     One commenter  (IV-D-31) recommended a level of 2 percent.
One commenter  (IV-D-40) recommended a 5 percent level.
                              2-14

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     Response;  The EPA concurs that it is undesirable for
this rule to regulate solvents that have become contaminated
with small amounts of halogenated HAP solvent.  The EPA did
not intend to discourage the recycling of solvent.  Therefore,
as mentioned previously, the EPA has clarified the
applicability section of the rule by adding a minimum
halogenated HAP solvent content concentration of 5 percent by
weight.  The EPA has determined that a level of 5 percent is
sufficient to exclude recycled solvents that have been
contaminated with halogenated HAP solvent.  These solvents
were never intended to be included in this NESHAP.
     Comment;  One commenter (IV-D-19) mentioned that the EPA
has begun development of de minimis thresholds for certain
halogenated solvents for draft regulations on constructed,
reconstructed, and modified major sources.  The commenter
recommended that the EPA establish such levels based on the
percentage of halogenated solvent used in the cleaning
mixture.
     Response;  The commenter is referring to de miniinis
levels established under section 112(g) of the CAA.  These
levels were established for the specific intent of 112(g) and
are not applicable to any other standard.  As discussed above,
a minimum halogenated HAP solvent content was added to ensure
that only those solvents intended for regulation are covered
by the final standards.
     Comment;  One commenter (IV-D-31) requested that the EPA
clarify in the preamble that CFC-113 is subject to a
production phaseout under other CAA mandated regulations.  The
commenter suggested that the following statement be
incorporated in the preamble to the final rule:
     "However, CFC-113 is not a recommended alternative.
     Like TCA, CFC-113 has been implicated as causing
     stratospheric ozone depletion, and is also being
     phased out under other EPA regulations under
     title VI of the CAA."
     Response;  The EPA's Significant New Alternative Policy
(SNAP)  program addresses the phase out of CFC-113.  The final

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SNAP program was published in the Federal Register on
March 18, 1994 (59 FR 13044).  The SNAP program presents
acceptable alternatives to CFC-113 for use in solvent cleaning
operations.  The EPA is also preparing a guidance document to
the halogenated solvent cleaning NESHAP.  One section of this
document will assist owners or operators of halogenated
solvent cleaning machines in the selection of acceptable
alternative solvents that can be used for their cleaning
needs.
2.1.2  Halogenated Solvent Cleaning Machines
     Comment:  Ten commenters (IV-D-15; IV-D-20; IV-D-21;
IV-D-31; IV-D-33; IV-D-34; IV-D-53; IV-D-54; IV-D-55; IV-D-60)
commented on the lack of a size cutoff for the proposed
standards.  One commenter (IV-D-33) supported the EPA's
decision to regulate all sources regardless of size.  However,
the commenter was concerned that the burden would be too great
on small sources that already have adequately controlled
residual emissions using different control equipment or
practices prescribed in this proposed regulation.
     One commenter  (IV-D-20) stated that one option would be
to exempt solvent cleaning machines that have solvent
interfaces of 1.0 square meter  (m2) or less,  because control
of such  small sources would not necessarily provide
substantial environmental benefits.  Another commenter
 (IV-D-34) requested that the EPA consider exempting very small
cleaning machines  (e.g., less than one gallon capacity) from
the requirements of the NESHAP.
     One commenter  (IV-D-54) stated that the EPA should
consider a de minimis threshold of solvent substitution beyond
which  a  source would no  longer be  a significant emitter of
halogenated HAP's  and would  also qualify for the source
category exemption.
      Another  commenter  (IV-D-31) recommended that the EPA
exempt small  units  from  the  regulation  and only require that  a
cover or an  enclosed reservoir  be  in place when the unit  is
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not in use, without requiring additional recordkeeping and
reporting requirements.  The commenter reasoned that this
would provide incentive for users to reduce their system below
the threshold quantity or surface area.
     One commenter (IV-D-53) recommended that the EPA set a
solvent emissions de minimis level of 3 Ib/hr (1.36 kg/hr).
Cleaning machines below this level would be exempt from the
rule.
     Two commenters (IV-D-15; IV-D-55) requested that a
halogenated HAP solvent quantity (threshold) be included as a
secondary screen for determining applicability, where if the
quantity is equal to or above the threshold level the
regulation would apply to them.  The commenters suggested that
10,000 Ib/yr (4,540 kg/yr), which is approximately 27 Ib/day
(12 kg/day), be used.
     Another commenter (IV-D-60) stated that the de minimis
level should be high enough so that small and seldomly used
cleaning machines are exempted from the rule, but low enough
so that 90 percent of area sources are covered by the
standard.
     Response;   The EPA believes that the cost effectiveness
associated with regulating halogenated HAP solvent cleaning
machines is reasonable.  There is insufficient evidence to
justify exempting a subset of small halogenated HAP solvent
cleaning machines from regulation.  Small halogenated solvent
cleaning machines [i.e.,  solvent-vapor air interface smaller
than (11 ft2)], in aggregate, are significant contributors to
national HAP emissions.
     The derivation of de minimis levels is required by law
under 112(g).  These levels are risk-based, and are therefore
different from the performance-based 112(d) MACT standards.
The EPA does not believe that a de minimis emission rate or
exemption based on solvent consumption is appropriate for this
source.  There is no justification to regulate a batch vapor
cleaning machine using a halogenated HAP solvent at one
                             2-17

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facility and not regulate a similar cleaning machine at
another facility based only on differences in frequency of use
or cleaning machine size.  If an owner or operator has already
installed controls, they could choose to comply with the
overall solvent emission limit standard, thereby reducing
their reporting and recordkeeping burden.
     Comment;   One commenter (IV-D-21) requested that the
proposed rule be revised to incorporate an exemption for
certain insignificant sources,  such as research operations and
other non-production operations, stating that this type of
exemption is consistent with the provisions of the Federal
Operating Permit Program, under Title V, which allows
exemptions for insignificant sources.
     Response:  The EPA is required by the Act [section
112(c)(7)] to establish a separate category covering research
or laboratory facilities, as necessary to assure the equitable
treatment of such facilities.  There is nothing inherently
different about research and laboratory facilities that would
justify a separate category or exemption.  The proposed and
final regulation for halogenated solvent cleaning machines
provide for equitable treatment of all halogenated HAP solvent
cleaning machine sources, by not exempting sources, such as
the ones described by the commenter.
     Comment;   Five commenters  (IV-D-28; IV-D-31; IV-D-40;
IV-D-48; IV-D-54) felt that the standards for batch cold
cleaning machines should be reevaluated.  One commenter
(IV-D-54) requested that the EPA establish a de minimis size
for batch cold cleaning machines (e.g., less than 50 gallons),
below which a machine would be exempt from all subpart T
requirements.   One commenter (IV-D-40) recommended adding an
exemption to the definition of cold cleaning machines and
solvent cleaning machines for very small cold cleaning
machines  (less than one gallon  (3.8 liters) capacity, or less
than  1.1 ft2  (0.1 m2) in surface area) from the NESHAP
requirements.
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     One commenter (IV-D-48) stated that they disagreed with
the extension of emission control standards and reporting
requirements to batch cold cleaning machines because these
machines typically use nonhalogenated solvents.  The commenter
stated that this requirement will result in excessive filing
requirements for industry and file management for regulatory
agencies and will negate any incentive for an operator to
practice source reduction by substituting for HAP solvents.
     Response;  The EPA does not believe that it is
appropriate to establish exemptions for cold cleaning
machines.  There is insufficient evidence to justify exempting
a subset of small cold cleaning machines from the regulation.
Small cold cleaning machines using halogenated HAP solvents,
in aggregate, could be significant contributors to national
HAP emissions.  The EPA concurs that the emission control
standards and reporting requirements of this NESHAP should not
be extended to batch cold cleaning machines that use solvents
not covered by this rule.  Batch cold cleaning machines using
nonhalogenated HAP solvents are not covered under the proposed
or final NESHAP.  The EPA has established a minimum
halogenated HAP solvent content concentration of 5 percent.
This halogenated HAP solvent content requirement will ensure
that cleaning machines using solvents containing a minimal
concentration of halogenated HAPs, which were never intended
to be regulated, are not regulated under this NESHAP.
     Comment:  Five commenters (IV-D-08; IV-D-25; IV-D-28;
IV-D-31; IV-D-34) discussed the scope of the batch cold
cleaning machine definitions.  One commenter (IV-D-34) stated
that cold cleaning machines encompass a wide variety of
specialized machines designed to clean small and specialized
parts, and are not limited to carburetor cleaning machines.
Another commenter (IV-D-25) stated that the proposed standards
for batch cold cleaning machines are inappropriate for
remote-reservoir cleaning machines.  The commenter felt it was
unclear whether the proposed standards are intended for
remote-reservoir cleaning machines.  One commenter (IV-D-08)

                             2-19

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suggested that the EPA combine the definitions of carburetor
cleaning machine and batch cold cleaning machine and regulate
only those machines that fit into the description now
appearing under the definition of carburetor cleaning
machines.  Under this approach, other solvent cleaning
operations not intended to be regulated by the EPA would not
be confused with those the EPA intended to regulate under the
NESHAP.
     Four commenters (IV-D-28; IV-D-31; IV-D-55; IV-D-60)
stated that batch cold cleaning machines should be defined
more narrowly.  Three commenters (IV-D-28; IV-D-55; IV-D-60)
suggested that the definitions of "carburetor cleaning
machine" and "cold cleaning machine" are unclear and imply
that the NESHAP would apply to any container of any size,
whether or not it incorporates any mechanical mechanism for
moving parts or solvents.  Two commenters (IV-D-28; IV-D-55)
recommended that a size or throughput cutoff be included for
the batch cold cleaning device or equipment to which the
NESHAP would apply.  Three commenters  (IV-D-28; IV-D-31;
IV-D-55) stated that the rule should not apply to containers
that do not incorporate all the components of a typical
carburetor cleaner.  One commenter (IV-D-60) recommended that
the EPA clarify the definition of cold cleaning machine to
include only discrete cleaning machines and exclude other
cleaning operations that do not use specialized equipment or
that are performed incidental to a particular industry's
process operation.
     Two comroenters (IV-D-55; IV-D-60) stated that the rule
should not apply to halogenated HAP solvents that are
circulated through process equipment for the cleaning of
process equipment.
     Response;  As stated at proposal, the EPA's intent is to
regulate emissions of the six listed halogenated HAP solvents
from all batch cold cleaning machines.  At proposal, the EPA
was not aware of any existing noncarburetor batch cold
cleaning machines using one of these halogenated HAP solvents.

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Therefore, the proposed standards applied to all batch cold
cleaning machines, but were based on controls for carburetor
cleaning machines.  Since proposal, the EPA has received
comment indicating that there are other noncarburetor cold
cleaning machines that use halogenated HAP solvents.  The EPA
has amended the final rule to include definitions for
remote-reservoir and other noncarburetor immersion batch cold
cleaning machines.  Batch cold cleaning machines are defined
in the final rule as including both immersion (including
carburetor cleaning machines) and remote-reservoir cold
cleaning machines, with the applicability of the rule applying
to batch cold cleaning machines that use one of the six
covered halogenated HAP solvents.
     The EPA agrees that the rule should not apply to
halogenated HAP solvents that are circulated through process
equipment.  The proposed and final rule do not apply to
cleaning machines that use halogenated HAP solvents that are
circulated through process equipment for cleaning.
     Comment:  Due to the low emissions from batch cold
cleaners and the fact that they are well controlled at
baseline, one commenter (IV-D-24) requested that batch cold
carburetor cleaning machines be classified as area sources.
     Response:   The EPA agrees that batch cold cleaning
machines are well controlled at baseline and by themselves are
area sources, which is why GACT rather than MACT was applied
to these area sources.  However, if a machine is located at,
and contributing to HAP emissions at a major source, it is
classified as part of that major source.  Therefore the EPA
has classified these sources as area and major sources.
     Comment;  One commenter (IV-D-33) suggested that the
regulation would be less confusing if the EPA subcategorized
the sources by small [less than 13 ft2  (1.21 m2)], and large
[greater than 13 ft2 (1.21 m2)] batch vapor cleaning machines,
in-line solvent cleaning machines, and batch cold cleaning
machines.
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     Response;  The EPA established the four size
subcategories for batch vapor cleaning machines during initial
regulatory development activities.  The sizes, based on known
cleaning machines, were used to evaluate control options and
impacts.  There is no added benefit to regrouping the cleaning
machines at this point in time.
     The EPA is currently preparing a guidance document to
help explain the final rule and assist owners or operators of
halogenated HAP solvent cleaning machines in complying with
the final rule.
     Comment;  One commenter (IV-D-33) stated that they do not
believe that there is sufficient basis to remove any
subcategories proposed by the EPA from the final rule based on
the delisting criteria in section 112(c)(9) of the Act.  The
commenter stated that it would not be possible for the EPA to
determine that "no source within the category" can be delisted
because a site-specific assessment of one degreaser cannot be
used to represent a subcategory of machines that have such
high variability in emissions.  The commenter does not believe
it is appropriate to compare the nation-wide exposure
estimates and other population-based risk estimates used in
the source category listing process to the acceptable risk
criteria for listing a subcategory established in
section 112(c)(9) of the Act.  The commenter  (IV-D-33)
suggested that the EPA develop a guidance document that
describes the approach being used to evaluate delisting
petitions according to the statutory requirements of
section 112(c)(9) of the Act.
     Response;  The EPA concurs with the commenter that there
is insufficient basis to remove any of the source
subcategories proposed and has therefore retained all of the
proposed subcategories in the final rule.  The EPA also agrees
that it is more difficult to go through the delisting process
than the listing process.  The EPA is developing a guidance
document that describes the approach being used to evaluate
delisting petitions according to the statutory requirements of

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section 112(c)(9) of the Act.  A draft of this document is
scheduled to be completed by fall of 1994.
     Comment;  One commenter (IV-D-23) stated that the
proposed NESHAP should not apply to halogenated solvent
cleaning machines on ships.  The commenter stated that the
proposed rule is linked in a number of essential provisions to
stationary sources (either major or area), which precludes
application to ships under existing definitions and applying
this rule to mobile sources is not practical.
     The commenter also stated that solvent cleaning machines
on ships have an insignificant potential for emissions since
there are existing economic incentives to avoid emissions and
existing standards that minimize emissions.  The commenter
added that there would be a heavy burden on both the Navy and
the regulating agency if the EPA tries to adapt the NESHAP to
these mobile sources.
     Response;  The EPA has considered this comment and
decided not to require compliance with these standards by
ships at this time.  The Agency will be considering the
generic issue of applicability of MACT or GACT standards to
ships at some time in the future.  Obviously, because they do
not remain in one location ships present complex issues
concerning compliance with Clean Air Act requirements.  At the
same time, it is clear that many large ships contain
operations that fit within the general applicability framework
for MACT standards.  These operations are not related to
whether or not the ships are regulated as mobile sources.  All
these factors will be considered when the EPA makes a
determination concerning whether to require ships to comply
with MACT standards.
     Comment:  One commenter (IV-D-04) was concerned that
halogenated solvents may also be used to dry parts and
suggested that standards should be written to cover those
operations.
     Response;  The EPA concurs with the commenter that there
is nothing inherently different about a machine that is used

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to dry parts as opposed to clean parts.  The rule has been
clarified to include machines used to dry parts.
     Cold Cleaners Using Haloaenated Solvents
     Comment;   Several commenters (IV-D-06; IV-D-22; IV-D-25;
IV-D-42) presented examples of batch cold cleaners using
halogenated solvents.  One commenter (IV-D-06) stated that
several electronics manufacturing facilities in their
jurisdiction had used TCA cold cleaners until very recently to
clean printed circuit boards for which manual touch-up work
was required.   These cleaning machines did not utilize a water
blanket as an emission control measure.  These manufacturers
have currently eliminated the use of TCA.  One commenter
(IV-D-22) stated that many NASA and contractor operations have
vapor degreasers or batch cold cleaning systems that use TCA
as a solvent.
     Three conunenters (IV-D-25; IV-D-42; IV-D-60) stated that
batch cold cleaning machines other than carburetor cleaners
use halogenated solvents.  One commenter (IV-D-42) gave an
example of small solvent sinks used in semiconductor
manufacturing that often use TCA.  Another commenter (IV-D-25)
stated that a cursory review of permits in San Diego County
indicates that at least 15 percent of batch cold cleaning
machines use halogenated solvents.  The third commenter
(IV-D-60) stated that they have cold cleaning machines that
use a halogenated solvent blend.  The cleaning machines vary
from discrete, custom designed assemblies with specialized
solvent lines and exhausts, to a sink with a solvent hood.
During cleaning, the parts are flushed with solvent from a
remote reservoir.  When cleaning is complete, all remaining
used liquid solvent  is drained to a solvent recovery loop.
Solvent emissions during the working mode are collected using
a lip exhaust  (on custom designed units) or a solvent hood  (on
simple sink operations) and routed either to the atmosphere or
to an appropriate control device, such as a carbon adsorber.
Parts movement is controlled using a hoist.
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     Response;   The EPA acknowledges that there are existing
batch cold cleaning machine operations using halogenated HAP
solvents where the requirement of a water layer would be
impractical.  Therefore, the EPA has included additional batch
cold cleaning machine equipment requirement options to control
emissions in the final rule.  Additional equipment options
include an increased freeboard ratio and cover, or
remote-reservoir design and cover, in lieu of a water layer
and cover.  The EPA has also added *ork practice requirements
for owners or operators choosing these alternative controls.
2.2  EMISSION CONTROL OPTIONS
2.2.1  Solvent Cleaning Machine Control Technologies
     2.2.1.1  General
     Comment:  One commenter (IV-D-12) disagreed with the
statement in the preamble that implied that halogenated
solvent loss rates are typically lowest during the downtime
mode as compared to idling and working modes.  However, the
commenter supplied no information or data to support this
statement.
     Response:  Based on the available data, the EPA maintains
that emission rates from solvent cleaning machines are
typically the lowest during the downtime mode.  However, the
total solvent losses during the downtime mode may exceed the
idling and working losses depending upon the operating
schedule employed by an owner or operator.  Section 2.3 of the
Background Information Document (Docket Number A-92-39,
Document Number II-A-15) provides a discussion of the basis
for the idling, working and downtime emission rates.
     2.2.1.2  Freeboard refrigeration devices
     Comment;  Six commenters (IV-D-12; IV-D-29; IV-D-31;
IV-D-36; IV-D-40; IV-D-42) discussed the requirement for
freeboard refrigeration devices (FRD) to achieve a required
air blanket temperature.  Two commenters (IV-D-12; IV-D-40)
stated that requiring the temperature in the center of the air
blanket to be 20 degrees below room ambient temperature is not
achievable and results will vary from solvent to solvent.  One

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commenter (IV-D-12) presented the differences in the boiling
points for MC and PCE.  The commenter stated that it was
unrealistic to expect the temperature in the center of the
vapor blanket to be the same for all solvents.  Another
commenter (IV-D-31) suggested that the amount of cooling that
the EPA has proposed would make it impossible to generate
solvent vapor.
     Two commenters (IV-D-31; IV-D-36) stated that it may be
very difficult to maintain a temperature at the center of the
air blanket that is exactly 20 degrees below the ambient room
temperature.  One commenter (IV-D-36) recommended that, to
allow flexibility, the phrase "is 20 degrees below the ambient
room temperature" should be changed to "is at least 20 degrees
below the ambient room temperature."
     One commenter (IV-D-42) recommended that the FRD
requirement in the rule be consistent with the FRD requirement
in the CTG, namely 40 degrees F or 30 percent of the solvent
boiling point on a degree F basis.  Another commenter
(IV-D-31) stated that the units should be in degrees F, as it
is not possible to depress the temperature 20 degrees C.  Two
commenters  (IV-D-31; IV-D-36) recommended that, as an
alternative to a blanket temperature requirement, the rule
specify an acceptable temperature range for the refrigerant in
the expansion coil (perhaps -10 to +2 degrees C).  If the
specification must be in terms of air blanket temperature, the
commenter recommended that the EPA specify that the Fahrenheit
scale is used, or specify 10 degrees Celsius.
     One commenter (IV-D-29) recommended that the requirement
that the temperature at the center of the air blanket is 20
degrees below the ambient temperature should be eliminated
because it  is difficult to implement and enforce.  The
commenter also expressed concern that the inspector would be
exposed to HAP's during inspection.
     Response;  The FRD requirement has been changed in the
final rule to be consistent with the FRD requirement in the
CTG.  Specifically, the FRD must achieve a chilled air blanket

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temperature, measured at the center of the cleaning machine,
that is no greater than 30 percent of the solvent's boiling
point (degrees F).  This requirement accounts for the
differences in solvent boiling points and therefore should be
more achievable.  In addition, the requirement no longer
specifies that a particular temperature be maintained and,
therefore, allows for fluctuations in temperature, provided
that the temperature never exceeds 30 percent of the solvent's
boiling point.  Lastly, the temperature is specified in
degrees Fahrenheit.
     A FRD requirement defined in terms of the refrigerant
temperature, as recommended by commenter IV-D-31, would be
difficult to establish and enforce.  Ensuring that the
refrigerant is at a proper cooling temperature does not ensure
that the FRD will adequately cool the air in the freeboard.
For example, a FRD might have only one very thin coil that
circulates properly cooled refrigerant but is incapable of
properly cooling the air in the freeboard.  Therefore, if one
were to regulate a FRD on the basis of refrigerant
temperature, one would also have to specify the size and
number of cooling coils, etc.   This type of requirement was
rejected based on its complexity, monitoring cost, and lack of
enforceability.  However, under the general provisions, a
facility could always propose such a requirement to the
Administrator.
     The FRD requirement that has been written into the final
rule can be easily monitored using a temperature probe.  The
probe can be lowered into an open top vapor cleaning machine.
For enclosed open top vapor cleaning machines and in-line
cleaning machines, the probe can be placed in the parts basket
and moved into position using the hoist.  These tests will not
disturb the vapor layer and the inspector will not be exposed
to any additional HAP emissions.
     2.2.1.3  Cover
     Comment;  One commenter  (IV-D-40) stated that hinged
covers should be deleted from the definition of a cover

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because they contribute to solvent losses when opened and
closed.
     Response;  The EPA agrees and has removed hinged covers
from the definition of a cover in the final rule.
     Comment;   Three coramenters (IV-D-11; IV-D-31; IV-D-51)
stated that there are a number of other mechanical devices
available that achieve the same type of emissions control as a
biparting cover.  These include slotted covers and complete
enclosure of the cleaning machine during the cleaning phase.
One commenter (IV-D-11) requested that the EPA revise the
proposed cover requirement to read:  "...Biparting cover or
equivalent to allow cover to be closed during the cleaning
phase..."  Another commenter (IV-D-31) requested that the
cover requirements be revised to allow the use of slotted
covers, manual covers that can be closed during working, or
any equivalent device.
     One commenter (IV-D-31) stated that the definition of
biparting cover should be changed by removing the word
"automatic" to permit the use of manually operated biparting
covers.
     Response;  The requirement in the final rule has been
changed from a "biparting cover" to a "working-mode cover."
A definition of a "working-mode cover" has been added to the
final rule.  The definition includes bi-parting covers and
other equivalent covers or procedures that allow the cover to
be closed while parts are in the cleaning machine.  In
addition, the definition of a "biparting cover" has been
expanded to include manual biparting covers.
     Comment;  One commenter (IV-D-51) stated that, because
bi-parting covers on large cleaning machines frequently break
down in the open position, in practice they provide no
additional emission reduction over roll-top or horizontal
covers, which break down less frequently.  The commenter
requested that roll top and horizontal covers be considered
equivalent to bi-parting covers for larger cleaning machines.
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     Response:  If a biparting cover is being used as part of
the compliance determination, the owner or operator of the
solvent cleaning machine must maintain the cover in good
repair or be in violation of the standard.  As stated
previously, the requirement for a "biparting cover" has been
changed to a "working-mode cover" which includes biparting
covers and other equivalent covers or procedures that allow
the cover to be closed while parts nre in the cleaning
machine.  In addition, the expanded definition of bi-parting
cover would include manual bi-parting covers.
     2.2.1.4  Reduced room draft
     Comment;  Several commenters (IV-D-10; IV-D-30; IV-D-31;
IV-D-34; IV-D-40; IV-D-41; IV-D-51)  questioned the technical
basis and selected level for the RRD requirement.  Four
commenters (IV-D-10; IV-D-31; IV-D-34; IV-D-40) stated that
reducing the room draft to 15.2 meters per minute (mpm)
(50 feet per minute [fpm]) or less cannot be achieved in most
metal cleaning facilities without completely enclosing the
equipment.  One commenter (IV-D-40)  questioned whether the
costs for an enclosure were included in the EPA's analysis.
The commenter added that, if an enclosure is used, the
monitoring of the air flow above the freeboard would become
impractical due to inaccessibility.
     One commenter (IV-D-34) recommended that the EPA consider
a higher level for the RRD requirement and more clearly define
what would be acceptable technology for attaining RRD.
Another commenter (IV-D-40)  recommended that the EPA consider
a requirement that the room draft be reduced to 50 percent of
the "typical" air flow.
     Another commenter (IV-D-31) stated that the EPA should
either increase the allowable velocity of air movement to an
attainable figure, and exclude situations where a cover is in
place, or delete the concept of RRD from the rule.  The
commenter suggested that, in the absence of statistically
significant data, the EPA should consider any air velocity
below 50 mpm (164 fpm) to be unattainable.  The commenter felt

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that further study would be required to determine an
achievable figure.
     One conunenter (IV-D-41) stated that the RRD velocity
should be reduced from 15.2 mpm (50 fpm) to 9.1 mpm (30 fpm),
as measured parallel to the plane of the degreaser opening,
unless the additional air flow is required to meet OSHA
requirements.
     One commenter (IV-D-51) stated that allowances should be
made to account for vapor cleaning operations in clean rooms.
A constant downdraft of 30 mpm (100 fpm) of highly filtered
air is maintained in these rooms to prevent airborne
contaminants from affecting product quality.
     Response;  The RRD requirement is based on emission
tests.  These tests showed that by reducing room drafts to
15.2 mpm (50 fpm), emission rates can be significantly
reduced.  For instance, by RRD from 30 mpm  (100 fpm) to
15.2 mpm (50 fpm), both working and idling emissions are
reduced by approximately 50 percent.  Further discussion of
RRD is found in chapter 3 of the proposal BID (Docket A-92-39,
Docket Number II-A-13).
     While the tests conducted by the EPA used an enclosure to
reduce drafts across the machine, the rule was written to
allow compliance flexibility for the facility.  The EPA has
determined that a variety of methods can be used to reduce
drafts over solvent cleaning machines.  These techniques
include, but are not limited to, redirecting air vents and/or
fans, moving the solvent cleaning machine to an area with less
cross-ventilation, closing windows, or enclosing the machine.
To maintain the flexibility of the rule, the EPA has not
specified the specific methods that must be used to achieve a
RRD.  The owner or operator may use any method as long as the
requirements for RRD are met and maintained.
     The final rule has been clarified by specifying that an
enclosure is a method  of achieving a RRD.  The EPA's cost
analysis included the  cost of an enclosure, as described in
Document No. II-B-22 of Docket No. A-92-39.  If the cleaning

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machine is enclosed, the monitoring of the air flow is
measured within the confines of the enclosure.
     The EPA recognizes that a cover and RRD control emissions
from a solvent cleaning machine in a similar manner.  This was
taken into consideration when determining the control
efficiencies for the control combinations in the final rule.
     The RRD requirement of 15.2 mpm (50 fpm) has been
retained in the final rule.  The EPA believes that this RRD
can be reasonably attained and provides good control of
solvent emissions.  Owners or operators are not required to
use a RRD to comply with the rule.  Additional control options
have been added to the final rule that do not include RRD.
     Owners or operators with solvent cleaning machines in
clean rooms may choose to comply with another compliance
option if they feel that the RRD requirement cannot be
implemented.
     Comment;  Seven commenters (IV-D-27; IV-D-30; IV-D-31;
IV-D-33; IV-D-40; IV-D-49; IV-D-54) were concerned that the
RRD could be in conflict with federal and State regulations on
ventilation, such as OSHA, or with consensus standards such as
those developed by the American Society of Heating,
Refrigerating and Air-Conditioning Engineers (ASHRAE).  One
commenter (IV-D-33) recommended that the RRD requirement be
removed from the control combinations and be replaced with
effective general ventilation requirements.
     Several commenters (IV-D-27; IV-D-40; IV-D-49; IV-D-54)
were concerned that the RRD control strategy would increase
occupational exposure by reducing room ventilation.  One
commenter (IV-D-27) believed that the degreasing shops would
not be able to distinguish between too much and adequate room
ventilation.  One commenter (IV-D-54) stated that it is
unlikely that the RRD requirement can be met by cleaners with
lip exhausts or other ventilation systems required for
industrial hygiene purposes.  The commenter (IV-D-54)
recommended that the EPA provide flexibility in the RRD
requirement in situations where ventilation is needed to

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protect workers.  Another commenter (IV-D-49) stated that
there may be other industrial operations emitting HAP's in the
workroom that require effective general ventilation to protect
workers.  The commenter stated that most industrial
establishments are designed to have an air change every
5 minutes as per industrial ventilation requirements.  The
commenter recommended that the owner or operator be able to
elect to use a lip type local exhaust ventilation system and a
carbon adsorber in order to comply with the RRD requirement.
     One commenter (IV-D-30) stated that, because of the
complex monitoring associated with the RRD control option, it
should not be included unless it is an important factor in
reducing emissions.
     Response;  No data have been provided by the commenters
that show that reducing the room draft across a solvent
cleaning machine increases worker exposure.  If an enclosure
is used to achieve a RRD, the owner or operator may maintain
the exterior ventilation at any level, provided it does not
disturb the air within the cleaning machine.  The final rule
does not encourage the use of a lip exhaust, and if the RRD
requirements cannot be met, an owner or operator can choose to
comply with the idling emission limit or the overall solvent
emission standard.
     If a high level of ventilation is required due to other
operations in the vicinity of the cleaning machine, the owner
or operator could move the machine to another part of the
facility or enclose the machine.  If the owner or operator
does not wish to implement a RRD, the owner or operator may
choose other control options that do not include a RRD.  The
owner or operator can choose to comply with the idling
emission limit or the overall solvent emission standard, which
do not necessarily require a RRD.  The EPA has concluded that
RRD is an important factor in reducing emissions.  In the
proposed rule, owners or operators were required to monitor
the RRD windspeed on a weekly basis regardless of the
technique used.  In the final rule, there are separate

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monitoring requirements for owners or operators that achieve a
RRD by controlling room parameters and those that use an
enclosure.  Owners or operators achieving a RRD by controlling
room parameters must measure the windspeed on a quarterly
basis and monitor the room parameters on a weekly basis.
Owners or operators achieving a RRD using an enclosure must
monitor the windspeed within the enclosure on a monthly basis.
     Comment;  One commenter (IV-D-31) stated that the RRD
requirements should not limit the owner/operator to one set of
operating conditions as long as the wind speed remains within
acceptable levels, as determined by monitoring during the
changed conditions.
     Response;  An owner or operator complying with the RRD
requirement by controlling room parameters must establish
these parameters in their compliance report.  The parameters
must then be monitored weekly along with quarterly measurement
of the windspeed above the cleaning machine.  An owner or
operator must notify the EPA in writing if they choose to
change one of these parameters.  Any change in the parameters
without prior notification would be a violation of the
standard.
     An owner or operator not wishing to maintain room
parameters to achieve a RRD may choose to comply with the RRD
using an enclosure.  If an owner or operator does not wish to
use a RRD to comply with the standard, the owner or operator
may comply with the rule through a control option that does
not require RRD or through the idling emission or the overall
solvent emission standard.
     2.2.1.5  Lip exhaust
     Comment:  Five commenters (IV-D-01; IV-D-10; IV-D-22;
IV-D-27; IV-D-41) commented on the requirement that all lip
exhausts on solvent cleaning machines must be vented to carbon
adsorbers (CAD's).  Three commenters  (IV-D-01; IV-D-10;
IV-D-27) expressed concern about the relationship between the
lip exhaust requirement and the ability to meet OSHA
regulations.  One commenter (IV-D-01) was concerned about the

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requirement in § 63.462(a)(6) of the proposed standard that
"No lip exhaust shall be used unless all collected solvent
vapors are routed through a carbon adsorber."  The commenter
(IV-D-01) stated that their company had installed lip exhausts
on their vapor degreasers when they converted from the use of
TCA to TCE in order to meet OSHA's 50 part per million (ppm)
permissible exposure limit (PEL).  The commenter stated that,
although they had a below-freezing chiller, they could not
meet the PEL so they installed a lip exhaust.
     Other commenters (IV-D-10 and IV-D-27) agreed that
requiring CAD's may discourage the use of a lip exhaust system
and may cause OSHA compliance problems for some facilities.
The commenters acknowledged that OSHA does not require a lip
exhaust, but it is one of several engineering controls that
could be employed to meet the OSHA limits.  Therefore, there
are many existing operations that currently employ lip
exhausts to meet OSHA limits.  The commenters expressed
concern that worker exposure could be increased if the NESHAP
discourages the use of a lip exhaust.
     Two commenters (IV-D-22; IV-D-41) stated that the venting
of lip exhausts to CAD's should not be required for all units.
One commenter (IV-D-22) stated that requiring all lip exhausts
to be vented to a CAD would place an undue financial burden on
infrequently used small and medium batch cleaners in the
aerospace industry.  The commenter (IV-D-22)  recommended that
the venting of lip exhausts to CAD's be addressed on a case-
by-case basis, based on the level of solvent use.  Another
commenter (IV-D-41) requested that solvent cleaning machines
that have minimal emissions be allowed to operate lip exhausts
that are not vented to CAD's.
     Response;  One commenter (IV-D-01) provided solvent
cleaning machine emission data from instantaneous readings
from colorimetric detector tubes.  The PEL is a time-weighted
average concentration for a normal 8-hour workday and a
40-hour work week, to which most workers may be repeatedly
exposed, day after day, without adverse effect.  Insufficient

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information was supplied by the commenter to determine whether
the 8-hour time weighted average (TWA) level would exceed
50 ppm.  This would depend on the number of work loads
processed and hours of operation of the cleaning machine.
Further information on the operations and equipment design
would be required to determine whether, without the lip
exhaust, the cleaning machine would comply with the OSHA PEL.
The short-term exposure limit (STEL) of 200 ppm was not
exceeded, based on data provided.  A STEL is defined as a
15-minute time-weighted average exposure concentration that
should not be exceeded at any time during a workday even if
the 8-hour time-weighted average is within the PEL threshold
limit value.
     The proposed and final rules require that if a lip
exhaust is used to comply with the equipment standard or the
idling emission limit, that all collected solvent vapors be
routed through a CAD.  The alternative standard does not
contain this requirement.  It is not the EPA's intent to
increase worker exposure.  It is also not the EPA's intent to
increase and reroute HAP emissions to the atmosphere.
Therefore, the EPA has revised the final rule to include CAD
as an option in the equipment control combination options.
This change recognizes a lip exhaust/CAD system as an
acceptable method to control emissions.  A carbon adsorber can
also be used in conjunction with an enclosure.  An owner or
operator may also choose to comply with the alternative
standard.
     Comment:  Two commenters (IV-D-27; IV-D-40) commented on
the proper operation of a lip exhaust.  One commenter
(IV-D-40) stated that it is important that lip exhausts be
placed above the cover, so that the cover closes below the lip
exhaust inlet level.  Another commenter (IV-D-27) stated that
a properly sized lip exhaust would not disturb the solvent
cleaning machine's vapor layer.
     Response:  In the final rule the EPA has clarified that
the lip exhaust must be located above the cover, so that the

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cover closes below the lip exhaust level.  The data available
to the EPA, as discussed in chapter 3 of the BID, show that
even a properly designed lip exhaust induces a draft across
the cleaning machine and pulls solvent vapor out of the
freeboard area.  This draft can disturb the vapor zone and
will increase diffusion of solvent from the vapor zone to the
freeboard area.  The EPA is not aware of any data supporting
the claim that lip exhausts do not disturb the vapor zone.
     2.2.1.6  Carbon adsorber
     Comment:  Nine commenters (IV-D-04; IV-D-10; IV-D-27;
IV-D-31; IV-D-33; IV-D-40; IV-D-41; IV-D-42; IV-D-49) were
concerned that the use of CAD's was discouraged in the
proposed rule.  One commenter (IV-D-10) stated that
discouraging the use of CAD may cause compliance problems for
those facilities that already have CAD's in place.  One
commenter  (IV-D-31) stated that emission reduction credit
should be given for the level of emission control achieved by
CAD's on existing in-line cleaners.  Another commenter
(IV-D-33) felt the EPA should allow States to continue to
require CAD's.
     Several of the commenters (IV-D-27; IV-D-31; IV-D-33;
IV-D-40; IV-D-41) stated that CAD's are a viable and cost
effective means of achieving emission reductions and should
not be discouraged from use.  One commenter (IV-D-33) added
that the EPA should include CAD's as a control technique in
conjunction with a lip exhaust system because they reduce
worker exposure to solvent vapors.
     One commenter (IV-D-04) stated that a CAD control
efficiency standard and test method should be added to the
rule.  One commenter  (IV-D-42) recommended that a 90 percent
efficiency standard for CAD's be written into the regulation.
Another commenter  (IV-D-40) stated that the EPA should revise
the proposed standards to include provisions to allow owners
and operators to use existing CAD systems, provided the
systems are operated within specified parameters.  One
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commenter (IV-D-33) recommended that the EPA reanalyze the
MACT floor to include CAD's.
     One commenter (IV-D-41) stated that, even though there
are multi-media impacts with CAD's, these do not offset their
advantages in many cases.  One commenter (IV-D-31) stated that
although some CAD technologies have the potential to produce
solvent contaminated regeneration water, there are other CAD
technologies that do not present that concern, such as vacuum
regeneration on activated carbon.  This method does not
produce any contaminated steam condensate and has an extended
carbon bed life.  The commenter (IV-D-31) requested that a
statement be added to the preamble stating that the EPA did
not intend to discourage any CAD technology that effectively
minimizes concern for cross-media impacts.
     One commenter (IV-D-33) stated that to reduce the water
impacts from CAD's, they should only be used to control dilute
HAP emissions, where the adsorber would be steamstripped
infrequently.  Another commenter (IV-D-49)  stated that CAD's
used to control toxic organic emissions from most common vapor
degreasers would not be expected to be stripped frequently
with steam,  nor to generate much contaminated wastewater.  The
commenter added that if CAD's are to be used in conjunction
with a lip local exhaust system, a MACT control level of
50 ppm should be required in order to control HAP's, such as
TCE, which is considered to be a suspect carcinogen.
     Response:  Carbon adsorbers used in conjunction with lip
exhausts have been added to the equipment standard of the
final rule.   A control efficiency of 40 percent for the
working mode and 40 percent for the idling mode was
established for CAD's used in conjunction with lip exhausts.
For the purposes of determining control combinations, the
efficiency of a CAD during idling was set at 0 percent.  This
control efficiency was used because an idling-mode cover is
required in all control equipment combinations, and a lip
exhaust routed to a CAD would be located above the cover.
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     The MACT floor does not need to be re-evaluated to
consider CAD's.  As stated in the proposal preamble, the MACT
floor was established based on a survey in which vendors
reported the controls that were sold with solvent cleaning
machines.  No CAD's were reported in this survey.
     The EPA did not intend to discourage any CAD technology
that effectively minimizes cross-media impacts.  The air
stream entering CAD systems from a solvent cleaning machine
will typically contain dilute HAP emissions, as indicated by
commenter IV-D-49.  Therefore, most CAD's installed on solvent
cleaning machines would be stripped infrequently.
     An exhaust concentration limit of 100 ppm of any
halogenated HAP solvent has been established in the final rule
as a monitored parameter.  The EPA set this halogenated HAP
solvent concentration as an indicator of proper CAD
maintenance and operation, concentrations above this level
would indicate a saturated carbon bed, requiring desorption.
If this level is exceeded, more frequent desorption is
required.  This maximum allowable concentration level is
measured in the exhaust from a CAD to the atmosphere and not
the indoor air.  Therefore, the EPA has not set a MACT control
level of 50 ppm for CAD.  An owner or operator is referred to
the method in the final rule to aid in the determination of
their CAD exhaust concentration.
2.2.1.7  Automated parts handling system
     Comment:  One commenter  (IV-D-41) requested that the
automated parts handling system speed requirement be changed
from 3.3 ropm  (10.8 fpm) to 3.4 mpm (11.2 fpm) to make this
rule consistent with the SCAQMD's rule 1122.
     Response:  The hoist speed requirement has been changed
from 3.3 mpm  (10.8 fpm) to 3.4 mpm (11.2 fpm) to make the
requirement consistent with the SCAQMD's rule 1122.  The final
value is the  approximate equivalent to 3.35 mpm  (11 fpm), the
basis for the SCAQMD's rule.
     Comment;  One commenter  (IV-D-04) stated that  it should
be clarified  in the definition for an automated parts handling

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system whether the system can be manually operated (e.g., a
chain hoist) or must be motorized.
     Response;  An automated parts handling system must be
able to consistently move parts within the confines of the
cleaning machine at a maximum speed of 3.4 mpm (11 fpm).  The
EPA feels that this is best achieved using a motorized system.
Non-motorized systems may be used if the owner or operator has
demonstrated in the compliance report, to the satisfaction of
the Administrator, that the system limits the speed of parts
movement within the confines of the cleaning machine to 3.3
mpm (10.8 fpm) or less.
     Comment:  One commenter (IV-D-22) stated that the
automated parts handling system is not applicable or
appropriate for many operations of batch cleaning machines in
the aerospace industry.  The commenter indicated that the
automated parts handling system is best suited for cleaning
machines that are in a production line.  The commenter
recommended that the requirement for an automated parts
handling system be addressed on a case-by-case basis within
the aerospace industry.
     Response;  As stated in the rule in the definition of an
automated parts handling system, automated parts handling
systems include, but are not limited to, hoists and conveyors.
The hoist required by the rule for open top vapor cleaning
machines can be any system that limits the speed of the parts,
as they move within the confines of the machine, to 3.4 mpm
(11 fpm).  Hoists can be easily installed for use in most
batch solvent cleaning operations.  Since the commenter does
not provide information on the design of their machines, the
EPA cannot evaluate the applicability of a hoist on their
machines.
     As an alternative, an owner or operator of a solvent
cleaning machine can choose to comply with the alternative
standard.  The alternative standard has no automated parts
handling system requirement.
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     The EPA believes that a case-by-case examination of the
automated parts handling system requirement is unnecessary and
would impose excessive burdens on the regulating authority.
     Comment:   Two commenters (IV-D-42; IV-D-50) provided
comments on the costs and savings associated with automated
parts handling systems.  One commenter (IV-D-42) was concerned
that the automated parts handling system requirement for all
batch vapor solvent cleaning machines is too burdensome for
small sources and that substantial justification for this
requirement needs to be provided.  One commenter (IV-D-50)
supported the automated parts handling requirement in the
proposed rule by stating that the manual cycling of parts is
not suitable because cycle times are not consistent.  The
commenter added that automatic handling provides significant
economic advantages in saving labor and provides much improved
employee working conditions.
     Response:  The costs of all the controls required by the
equipment standard have been evaluated and considered to be
reasonable.  However, an owner or operator of a solvent
cleaning machine can choose to comply with the alternative
standard, which has no automated parts handling system
requirement.  The automated parts handling requirement has
been maintained for the equipment standard and the idling
standard in the final rule.
     2.2.1.8  Super-heated vapor
     Comment:  Five commenters  (IV-D-12; IV-D-34; IV-D-40;
IV-D-50; IV-D-56) provided comments on the applicability and
design requirements of super-heated vapor  (SHV).  Three
commenters  (IV-D-12; IV-D-34; IV-D-40) expressed concern about
the applicability of SHV technology.  One commenter  (IV-D-34)
stated that the practicality of retrofitting SHV is still
unproven.  Two commenters  (IV-D-50; IV-D-56), both
representing the same vendor of SHV technology, indicated
that, due to new developments with the technology, SHV is
currently available for retrofitting on existing cleaning
machines.  The cleaning machine to be retrofitted must be  in

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good operating condition, have automated operation, and meet
the other basic equipment requirements as proposed in the MACT
control combinations.
     Two commenters  (IV-D-34; IV-D-40) stated that SHV is
unrealistic for solvents with a higher boiling point such as
PCE, which would require a minimum vapor temperature of 360
degrees F (1.5 times the boiling point).  One commenter
(IV-D-56), representing a vendor of SHV technology, stated
that the requirement that the super-heated vapor zone be
1.5 times the boiling point of the solvent should be changed.
The commenter indicated that the proper temperature would be a
minimum of 10 degrees Fahrenheit above the boiling point of
the solvent.  The commenter noted that it only takes a slight
increase in temperature difference between parts and the
solvent boiling point before the parts will no longer condense
solvent.
     Another commenter (IV-D-50), representing the same vendor
of SHV technology, stated that SHV has been effective on
machines using fluorocarbons, TCA, TCE, MC and PCE.
     One commenter (IV-D-12) had several comments on SHV:
     (1) a control efficiency should be listed for SHV;
     (2) super-heated vapor should not be described as an
idling emission control device because it is utilized for
drying parts during the working mode;
     (3) hot vapor recycle should not be defined as a cleaning
technology because it is employed in vapor degreasers to
remove or evaporate entrapped solvent after parts are cleaned;
     (4) the definition for SHV systems should exclude the
phrase "more than 1.5 times greater than the solvent boiling
point" because thermal decomposition can occur when
temperatures exceed 1.5 the atmospheric boiling point of the
solvent; and
     (5) super-heated vapor should only be utilized when
rotation or part orientation does not allow entrapped solvent
to be removed.
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     Besponse;  A vendor of SHV technology (IV-D-50; IV-D-56)
has stated that SHV is currently available for retrofitting
and therefore control combinations containing SHV may be
available for existing machines.
     The EPA has addressed SHV applicability concerns by
modifying the SHV requirements in the final rule as
recommended by commenters IV-D-50 and IV-D-56.  The
requirement that the SHV system heat the solvent vapor to 1.5
times the solvent's boiling point has been removed.  The final
rule states that the SHV system must heat the solvent vapor to
at least 10 degrees Fahrenheit above the solvent's boiling
point.  Using this SHV requirement, commenters IV-D-50 and
IV-D-56 stated that SHV is effective on cleaning machines
using fluorocarbons, TCA, TCE, MC, and PCE.
     Super-heated vapor has a control efficiency of 50 percent
during the working mode and 0 percent during the idling and
downtime modes.  Contrary to commenter IV-D-12, SHV was not
described in the proposed rule as an idling control device.
As required in § 63.465(a)(3) of the proposed rule, the
monitoring of the SHV temperature is done during the idling
mode when there is no disturbance of the vapor zone due to
parts movement.  This monitoring requirement is not meant to
imply that SHV controls idling emissions.
     The reference to hot vapor recycle as a cleaning
technology has been removed from the hot vapor recycle
definition in the final rule.
     Comment;  Two commenters (IV-D-31; IV-D-34) asked whether
all technologies using SHV would be considered equally
effective by the proposed standards.  One commenter (IV-D-31)
stated that super-heated vapors are a source of turbulence
and, in some cases, are injected into the vapor zone with
considerable velocity.  Because of this, a SHV system can
actually increase emissions.  One commenter (IV-D-34)  stated
that non-disruptive radiative heating is the best method of
super-heating.  The commenter stated that the EPA should
clarify whether hot vapor recycle  (HVR) is an acceptable means

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of employing SHV under the rule.  If it is, the commenter
would be concerned that the hot vapor recycle could actually
increase emissions due to vapor zone disturbance.
     Response;  All technologies using SHV that meet the SHV
requirements specified in the final rule are considered to be
equally effective.  The EPA has not identified any data that
show that active SHV systems, which circulate solvent vapor in
the vapor zone, increase solvent emissions.  However, it is
reasonable to expect that this could occur in some situations.
     Hot vapor recycle systems that meet the SHV requirements
in the final rule can be used to comply with the equipment
standard.
     2.2.1.9  Increased freeboard height
     Comment:  Two commenters (IV-D-31; IV-D-34) stated that
in order to raise the freeboard of an in-line cleaner, the
entrance and exit port must be extended in order to compensate
for longer incline runs.  They stated that this would have the
effect of increasing the overall length, as well as the
height, of the machine.  The commenters stated that this would
have a dramatic economic impact on operations limited by
existing facility space.  One commenter (IV-D-34) stated that
the agency should consider this impact in its economic
analysis and the proposal to require all existing in-line
cleaners to comply with a 1.0 freeboard ratio should be
re-evaluated.  Another commenter stated that the requirement
to increase the freeboard ratio to 1.0 is more appropriate for
new in-line cleaners than for existing in-line cleaners.  The
commenter (IV-D-31) stated that the EPA should provide other
compliance options, such as carbon adsorption, that are
realistically attainable for in-line cleaning machines.
     Response:  The EPA added additional in-line cleaning
machine equipment control combinations in the final rule that
do not include an increased freeboard height.
     2.2.1.10  Dwell time
     Comment;  Several commenters (IV-D-20; IV-D-29; IV-D-30;
IV-D-35) recommended removing the dwell as a control option.

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One coitumenter (IV-D-30) stated that the dwell time should be
removed because it seems to be a very unreliable control
method.  Three commenters (IV-D-20; IV-D-29; IV-D-35)
recommended eliminating the dwell time option because it is
difficult for industry to implement and enforce.
     Response;  Available test data show that the dwell-time
technique can reduce working emissions by 30 percent.  These
test data are presented in section 3.10 of the technical
memorandum titled, "Summary of Emission Reductions for
Selected Control Techniques for Halogenated Solvent Cleaners"
(Docket Number A-92-39, Document Number II-B-19).
     When a hoist is used, a dwell can be implemented
relatively easily.  This is especially the case for machines
that have programmable hoists.  If an owner or operator does
not wish to use the dwell-time control technique, the
equipment standard provides other control options.  In
addition, owners or operators have the option to comply with
the idling emission limit or the alternative standard, neither
of which require the dwell-time control technique.
     Comment:  Two commenters (IV-D-37; IV-D-40) referred to
the dwell determination procedure in § 63.464(c) of the
proposed rule, and stated that it would be impractical to
determine dwell times  for each of the thousands of different
part combinations that are cleaned each day.  One commenter
(IV-D-37) recommended  that the EPA state in the rule that the
drip and dwell time determinations may be based on operator
judgement considering  the type and quantity of parts being
cleaned.  The other commenter (IV-D-40) recommended that the
EPA specify  a dwell time.  The commenter suggested that the
dwell  time could be specified as a number of seconds  (e.g.,
15, 30, 45)  after the  last liquid contact.  The commenter
recommended  that, in the case of in-line cleaners, the
equipment manufacturer may specify a minimum dwell that the
EPA could require operators to follow.
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     One commenter (IV-D-40) stated that the dwell time is
considered the amount of time the part is held above, not in,
the vapor zone.
     Response:  The provisions for calculating the proper
dwell time are based on the proper cleaning time that the
owner or operator should already have established.  If one
ideal cycle time has been determined for a group of load
types, then the same dwell time can be used for these loads.
The EPA has added a provision to the final rule that allows an
owner or operator to determine the dwell time for the most
complex part  (i.e., the maximum dwell) and then use this dwell
time for all parts.  The EPA will not specify a dwell time,
but will maintain the flexibility of the proposed dwell
requirement in the final rule.
     The EPA has defined the dwell time correctly in the
proposed rule and has included this definition in the final
rule.  The dwell time is defined as the technique of holding
parts within the freeboard area but above the vapor zone of
the solvent cleaning machine.  The commenter (IV-D-40) may
have been confusing this definition with the method of
determining the appropriate dwell time.  The proper dwell time
is equal to 35 percent of the time for the part or parts
basket to cease dripping once placed in the vapor zone.
     2.2.1.11  Sump cool-down coils
     Comment;  One commenter (IV-D-12) mentioned that solvent
sump cool-down coils, though not considered in the EPA's
proposed rule, can significantly reduce downtime emissions.
     Response;  Very limited data were available on the
control efficiency of sump cooling devices.  Therefore, they
were not included in the rule.  However, the rule does not
preclude their use to comply with the overall solvent emission
limit standard.  In addition, the equivalent methods of
control section of the rule allows an owner or operator to
demonstrate that sump cooling devices are equivalent to a
control specified in the equipment standard.
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     2.2.1.12  Waterlayer (cold cleaning machines)
     Comment;  Many commenters (IV-D-08; IV-D-31; IV-D-34;
IV-D-40; IV-D-42; IV-D-44; IV-D-54; IV-D-60),  stated that a
water layer cannot be used on non-carburetor batch cold
cleaners.  The reasons include:  the parts that are being
cleaned are water sensitive (such as iron parts or electronic
components); the cleaner design makes a water layer
impractical (such as an enclosed "glove box" solvent spray
cleaner); or the solvent being used is miscible in water or is
reactive in water (such as TCA).
     One commenter (IV-D-45) stated that they have water
intolerant parts and are currently evaluating switching to a
cold cleaning system.  The commenter is concerned about the
water cover requirement for batch cold cleaners in
§ 63.462(g)(2) of the proposed rule and proposed that a cold
solvent rinse variation be added to the cold solvent cleaning
option.  The commenter offered to provide data from their
evaluation of cold cleaners and requested the opportunity to
comment on what the EPA decides regarding this issue.
     Another commenter (IV-D-25) stated that the provisions of
§ 63.462(g) of the proposed rule do not represent GACT for all
batch cold cleaners using halogenated solvents.  The commenter
stated that the nature of some operations would make it
difficult to have a closed, tightly fitted cover at all times
except during parts entry and removal as required in
§ 63.462(g)(l) of the proposed rule.
     The commenters recommended that the EPA provide
flexibility in the batch cold cleaning machine requirements to
allow the use of other controls in lieu of a water layer.  One
commenter  (IV-D-31) recommended that a water layer should only
be required for carburetor cleaners.  The commenter  (IV-D-31)
suggested that a tightly fitting cover, or remote reservoir be
required for non-carburetor cold batch cleaners.  One
commenter  (IV-D-08) asked the EPA to consider an exemption
from the use of a water layer in batch cold solvent cleaning
machines in situations where residual water cannot be

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tolerated.  One commenter (IV-D-54) asked the EPA to accept
the enclosed "glove box" cleaner as GACT or develop emission
standards for cold cleaners based on a solvent mass balance.
Two commenters (IV-D-34; IV-D-40) asked the EPA to add the
combination of a cover and an extended freeboard to the batch
cold cleaner compliance options.  One commenter (IV-D-25)
recommended that the rule allow a freeboard ratio of at least
0.75 as an alternative to the water layer.
     Another commenter (IV-D-60) st.ited that the proposed
standards for cold cleaning machines that were fashioned after
the carburetor cleaning machine would not readily apply to
their batch cold cleaning machines because their cleaning
system uses solvent flushing and a remote reservoir.  The
commenter recommend that the EPA eliminate the mandatory
requirement for a water layer and allow for "enclosing" the
device as an alternative to "covering".  The commenter
provided recommended language for this change.
     Response:  The EPA acknowledges that a water layer cannot
be used in batch cold cleaning machines that clean parts that
are water sensitive; where the solvent used is miscible in, or
reactive with, water; or where the cleaning machine design
makes a water layer impractical.  Therefore, the EPA has
included flexibility in the batch cold cleaning machine
control equipment requirements in the final rule.  As
previously discussed, the use of a remote-reservoir and cover,
or a freeboard ratio of 0.75 and a cover, in lieu of a water
layer have been included in the final rule as alternative
options for batch cold cleaning machines.  The final rule also
allows for the use of alternative control equipment to those
included in the final rule if approved by the Administrator.
2.2.2  Control Combinations
     Comment;  One commenter (IV-D-40) stated that the
combined control efficiency formula [Eeff = E^ + £2 - (EiE2)]
does not accurately predict emission reductions for control
equipment combinations.
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     Response;  The commenter provided no data or reasoning
that would allow the EPA to assess the validity of this
comment.  The EPA feels that this equation is a proper method
of calculating the efficiency of multiple controls acting in
series.  The formula has been checked using actual test data
and has been found to be a reasonable representation.
     Comment;  One commenter (IV-D-33) stated that it would be
useful for the EPA to present the analysis that was performed
to develop the control combinations in tables 1 and 2 of the
regulation.  The commenter would like to determine whether
certain control combinations achieve the same control
efficiency.  The commenter stated that further comments on the
control combinations is dependent on this information.
     Response:  The development of the control combinations is
described in section 4.2 of the Background Information
Document  (Docket Number A-92-39, Document Number II-A-15).
The control combinations have been revised based on public
comments.  Specifically, CAD has been added to the analysis
and redundant controls have been removed.
     Comment;  One commenter (IV-D-34) stated that the EPA may
be relying too heavily on super-heated vapor  (SHV) technology
in its control combination options for large open top vapor
solvent cleaning machines.
     Response:  The EPA does not agree that it is relying too
heavily on SHV technology in its control combination options
for large open top vapor solvent cleaning machines.  Two
equipment options exist for large open top vapor cleaning
machines that do not contain SHV.  In addition, an owner or
operator can choose to comply with the idling emission limit
or the alternative standard, which do not have a SHV
requirement.
     Comment:  One commenter (IV-D-51) recommended increasing
the flexibility of the rule by adding the following control
combination for batch vapor cleaning machines:  FRD, 1.0 FBR,
horizontal cover, hoist at 3 mpm  (10 fpm), and RRD 15.2 mpm
 (50 fpm).

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     Response;  The control combination of a hoist at 3.4 mpm
(11 fpm) ,  idling-mode cover, FRD, 1.0 FBR, and RRD, was
included in the analysis of control combinations when
developing regulatory alternatives for the final rule.  A
small or medium batch vapor cleaning machine with these
controls could comply with the rule using control option 5 or
6 in table 1 of the final rule.  A large or very large batch
vapor cleaning machine with these controls could comply with
the rule using control option 6 in table 2 of the final rule.
     Comment;  One commenter (IV-D-42) asked why the proposed
rule has fewer control options for small units than there are
for large units.
     Response:  The difference in the number of control
combinations between small and large open top vapor cleaning
machines was a result of the control combination analysis.  At
proposal, four control combinations were found to achieve the
MACT level of control for small cleaning machines, whereas 7
controls achieved the MACT level of control for large
machines.  In the final rule, there are 10 control options for
small and medium solvent cleaning machines and 7 control
options for large and very large cleaning machines.  This
increase in the number of control options for small and medium
solvent cleaning machines is the result of lowering the MACT
level of control for these subcategories and including carbon
adsorbers.
     2.2.2.1  Bipartinq cover and reduced room draft
     Comment:  Several commenters (IV-D-10; IV-D-32; IV-D-34;
IV-D-40) stated that RRD and a cover are redundant.  One
commenter (IV-D-10) recommended that the RRD control be
removed from all combinations that also include a cover.  This
would give metal cleaning operations the flexibility to choose
control options that do not include RRD.  One commenter
(IV-D-32) referred to the Background Information Document
(BID) to support their conclusions.
     Response;  The EPA agrees that the combined efficiency
formula overstates the emission reduction when a RRD and a

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bi-parting cover are used in the same control combination.
Therefore, RRD a bi-parting cover are no longer included in
the same combination.  Removing the control combinations that
contained both RRD and a bi-parting cover resulted in a
reduction of the MACT level of control for small and medium
solvent cleaning machines from 60 percent to 50 percent.  This
increased the number of control options available to owners
and operators of these cleaning machines from 4 to 10.
2.2.2.2  Super—heated vapor and freeboard refrigeration
devices
     Comment:  Two commenters (IV-D-31; IV-D-32) felt that a
SHV device and FRD were not a viable combination.  One
commenter (IV-D-32) stated that the combination of a SHV
device and a FRD is technically impractical and has the added
risk of being excessively costly and energy dependant.
Furthermore, because super-heated vapor is a new technology,
the commenter doubted whether the control combination would be
available for installation.  One commenter (IV-D-31) stated
that they suspected that the control combination of a SHV
system and a FRD would not achieve the desired results in many
instances.
     Response;  No data has been provided to the EPA to
indicate that the combination of a SHV system and a FRD is not
viable.  On the contrary, suppliers of SHV recommend that
additional cooling capacity through the use of a super-cooled
primary condenser be added to the solvent cleaning machine
when retrofitting a SHV system  (Docket Number A-92-39,
Document Number II-E-23 and II-E-24).  The EPA believes that a
FRD could provide such additional cooling capacity.
Therefore, combinations containing both SHV and FRD have not
been removed from the rule.
     A vendor of SHV systems has indicated to the EPA that SHV
is currently available on new solvent cleaning machines and
for retrofitting on existing solvent cleaning machines  (Docket
Number A-92-39, Document Number IV-D-56).  Therefore, SHV is
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considered to be an available technology and has not been
removed from the rule.
     2.2.2.3  Freeboard refrigeration device and primary
cooling cools
     Comment;  One commenter (IV-D-27) was concerned that if
the EPA stated in the rule that cooling coils are redundant
with a refrigerated condensing system some facilities may
disconnect their cooling coils.  The commenter suggested that
the standard should state that the primary cooling coils
should be used even if a refrigerated system is present.
     Response;  When citing the example discussed by the
commenter (IV-D-27),  the EPA was referring to a super-cooled
primary condenser and an FRD (both a primary condenser and an
FRD must achieve a chilled air blanket temperature that is no
greater than 30 percent of the solvent's boiling point).  Data
show that a limited additional emission reduction is achieved,
when an FRD is added to a cleaning machine using a super-
cooled primary condenser.  The rule requires that the primary
condensing coils be operated according to the manufacturer's
recommendations.
     In-line cleaners
     Comment:  One commenter (IV-D-25) stated that requiring
controls in § 63.462(c)(l)(i) of the proposed rule that reduce
convection and diffusion losses from in-line cleaning machines
is excessive.  The commenter stated that the emission controls
for in-line cleaners should focus on the reduction of solvent
losses from parts movement since in-line cleaners are enclosed
except for typically small parts inlet and exit openings.
     Response:  In-line cleaning machines typically have two
openings, and therefore drafts can pass through the machine
and increase solvent emissions.  The requirements for a
1.0 FBR and FRD in § 63.462(c)(1)(i) of the proposed rule and
the cover requirement in § 63.462(a)(1) and § 63.462(d)(l) of
the proposed rule would help reduce the convection and
diffusion losses associated with drafts passing through the
openings in the cleaning machine.  The required provision

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remains in the final rule to ensure adequate design of all
in-line cleaning machines.
     The control of working losses is addressed in the rule.
There are several requirements to control solvent losses from
parts movement that are applicable to all in-line cleaning
machines complying with § 63.462 of the proposed rule.
Examples are the hoist speed requirements in § 63.462(a)(3)
limiting hoist speed and the work practice requirement in
§ 63.462(d)(5) that requires parts to be orientated so that
solvent drains from them freely.
     Comment:   One commenter (IV-D-31) stated that the
combination of a freeboard ratio of 1.0 and a FRD should be
added as a compliance option for new in-line cleaning
machines.
     Response;  The combination of a 1.0 freeboard ratio and a
FRD achieves an overall emission reduction of 50 percent on an
in-line cleaning machine.  MACT for new in-line cleaning
machines is 60 percent overall control.  Therefore, the
commenter's proposed control option does not achieve the MACT
level of control for new in-line cleaning machines and has not
been added to the final rule.  However, if a cleaning machine
with a combination of a 1.0 freeboard ratio and a FRD can meet
the overall emission limit standard, this combination can be
used to comply with the rule.
2.2.3  Alternative Cleaning Technologies
     Comment;   Eight commenters (IV-D-03; IV-D-10; IV-D-20;
IV-D-29; IV-D-35; IV-D-40; IV-D-49; IV-D-54) discussed
potential impacts of switching to alternative control
technologies.   One commenter (IV-D-10) presented a number of
examples where cleaning technology alternatives cited in the
preamble presented potential application, health, or
environmental problems.
     Two commenters  (IV-D-20; IV-D-29) were concerned with a
switch to an alternative solvent that may not be presently
classified as a toxic air contaminant, but may cause toxic
health effects, global warming impacts, or stratospheric ozone

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depletion effects [e.g., hydrochlorofluorocarbons (HCFC's)].
The commenters believe that if the EPA does not prohibit
facilities from switching to an HCFC, CFC-113, or another
alternative solvent, many facilities may switch to another,
possibly equally damaging chemical, to escape burdensome
regulation under the NESHAP.
     Three commenters (IV-D-03; IV-D-10; IV-D-40) were
concerned that the proposal preamble referred to HCFC's as
potential alternatives to the chlorinated solvents in cleaning
machine operations.   Two commenters (IV-D-03; IV-D-10) stated
that HCFC's are not viable alternatives since they will be
phased out because of their potential to deplete stratospheric
ozone.  The third commenter (IV-D-03) recommended that OAQPS
coordinate -with the EPA's Global Change Division, in its
Significant New Alternatives Policy (SNAP)  for the latest
information on potential alternatives to the chlorinated
solvents used in cleaning machine operations.
     One commenter (IV-D-40) stated that under the proposed
SNAP program, HCFC's are not generally considered acceptable
substitutes to MCF and CFC-113 in solvent cleaning,  except for
certain precision applications.  The commenter (IV-D-40)
stated that the alternative processes listed on page 62526 of
the proposed preamble are unlikely to be viewed as
alternatives to halogenated solvent cleaning.  Many are still
in development and most are limited in their ability to clean
oils and greases.  All are significantly more expensive than
halogenated solvent cleaning.
     One commenter (IV-D-35) suggested that the exemption of
alternative solvents that are VOC's is not beneficial in areas
where ground-level ozone is a problem.  These alternative
solvents may cause other detrimental health and environmental
effects, despite not being listed as HAP's.  The commenter
suggested that the consequences of using such alternative
solvents be evaluated and appropriate control required.
     Two commenters (IV-D-03; IV-D-54) stated that the rule
should provide incentives for the substitution of halogenated

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solvents with alternative cleaning technologies.  One
commenter (IV-D-03) stated that these alternative methods
should be designated as MACT and a cost analysis performed.
Another commenter  (IV-D-54) stated that, if a source makes a
complete switch from halogenated solvent cleaners to
alternative cleaners or cleaning technologies, it should be
immediately exempt from the halogenated solvent cleaners
source category.  Another commenter (IV-D-49) supported the
pollution prevention strategy of using alternative cleaning
technologies to replace halogenated solvents as the primary
means of minimizing these toxic emissions.
     Response;  The EPA recognizes that alternative cleaning
technologies are potential substitutes for halogenated solvent
cleaning technologies.  As stated in the proposal preamble,
the EPA did not mandate a switch from halogenated solvents to
an alternative solvent or technology for the following
reasons:
     1.  Controls  exist that can significantly and efficiently
reduce the emissions of halogenated solvents from solvent
cleaning machines.  These controls can reduce emissions to a
level more stringent than the MACT floor for these units.
     2.  Determination of an acceptable alternative cleaning
technology is site- and application-specific and can take
years.  Not all of the applications are known, and it is
uncertain whether  an acceptable alternative technology exists
for every application.
     3.  While HAP use could be eliminated or reduced,
discharges of HAP  to wastewater or air could be increased.
Because the switch from a halogenated solvent cleaning machine
system to an alternative solvent system is application
specific, the relative impacts of making a total switch cannot
be confidently assessed.
     Before proposal of these standards, alternative cleaning
agents and technologies were fully evaluated as potential
control options.   The EPA agrees that a number of the cited
alternative cleaning technologies may have associated

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application, health, or environmental problems.  No new data
were provided during the public comment period to change this
position.  Therefore, the EPA has concluded that mandating
facilities to switch from the use of a halogenated HAP solvent
to an alternative nonhalogenated HAP solvent that may have
potential adverse environmental impacts is not warranted under
this NESHAP.
     The EPA has extended the compliance time for the rule
from 2 years to 3 years.  This will give owners or operators
of solvent cleaning machines more time to evaluate
alternatives to halogenated HAP solvent cleaning.
     The EPA will be developing a guidance document to the
final rule that will include a discussion on the EPA's Global
Change Division's Significant New Alternatives Policy (SNAP)
and the Solvent Alternatives Guide (SAGE).  The document will
offer guidance on where to obtain the best alternative
cleaning options for particular cleaning needs.  The document
will also include a list of those solvents that are not viable
replacement options because they will be phased out due to
their potential to deplete stratospheric ozone.
     The EPA agrees that an owner or operator of a halogenated
solvent cleaning machine that switches to an alternative
nonhalogenated solvent technology should not have to comply
with the NESHAP.  The proposal and final rule applicability
pertains to the owners and operators of solvent cleaning
machines that use halogenated HAP solvents.  If alternative
solvents are used that are not halogenated HAP's the rule does
not apply.  However, the EPA does not agree that people are
likely to change from the use of halogenated HAP solvents
solely to escape this rule.  This rule is not sufficiently
burdensome to cause this and will actually result in a cost
savings for many facilities.
     Comment:  One commenter (IV-D-30) recommended that the
EPA use the Puget Sound Air Pollution Control Agency's
(PSAPCA's) experience to improve the regulation.  The PSAPCA
program could be used to develop the contents of, and minimum

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standards for, required alternatives analysis.  The commenter
indicated that the PSAPCA has a regulation that makes it
unlawful to operate a vapor degreaser employing a toxic air
contaminant unless an analysis has been conducted which
demonstrates that no acceptable alternative exists.  According
to the commenter, this regulation has been very successful in
reducing the number of sources using halogenated solvent
cleaners.  The commenter claimed that the initial review could
eliminate the need to undertake the various complicated
control, recordkeeping, and reporting requirements by
encouraging these sources to use more "environmentally safe"
cleaning options.  These options could include replacing
existing halogenated solvent degreasers with aqueous or
semi-aqueous parts washers, aqueous immersion tanks, alkaline
cleaners or a combination of these.
     Response;  The PSAPCA's program has merit.  However, the
EPA does not have the resources to adopt this program
nationally.  The EPA's final standard encourages owners or
operators to evaluate alternatives.  However, since
alternatives can have adverse impacts and may not be usable in
all cases, the EPA did not mandate the use of alternatives.
The Agency is developing a guidance document to aid owners and
operators of halogenated solvent cleaning machines in
evaluating available alternatives.  The EPA has determined
that the final standards sufficiently control halogenated HAP
emissions for this source.
     Comment;  Three commenters (IV-D-10; IV-D-31; IV-D-54)
expressed concern that the EPA may require alternative
technologies  for specific applications based on information
obtained before the rule is promulgated.  One commenter
(IV-D-54) stated that a substantial change to the basis of the
rule could be disruptive to the planning that has begun based
on the proposed rule.  Two commenters (IV-D-10; IV-D-31)
stated that it would be inappropriate for the rule to require
alternative technologies for particular cleaning applications
without a separate proposal and opportunity for comment.

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     One commenter (IV-D-10) agreed with the EPA's position
that the NESHAP should not mandate the use of any particular
alternative cleaning technology.  The commenter stated that
the EPA should allow sources affected by the rule as much
flexibility as possible in complying with the MACT standards.
Another commenter (IV-D-31) stated that the EPA could
facilitate the alternative evaluation process by maintaining a
nonbinding list of consulting services, available to
businesses on request.
     Response;  The EPA has retained the rule's flexibility
and has not mandated the use of any particular alternative
cleaning technology.   The flexibility of the rule has been
increased by the addition of multiple new control combinations
and by providing a means of compliance for solvent cleaning
machines that do not have a solvent/air interface.
     The EPA does not have the ability to continually update
and maintain a nonbinding list of consulting services.
     Comment:  In reference to the discussion in the proposed
preamble on no-clean technologies (page 62572), one commenter
(IV-D-40) stated that the cleaning of metals can rarely be
eliminated, although reducing the amount of cleaning required
is often possible.  The commenter (IV-D-40) also stated that,
contrary to the discussion in the preamble, dry-film
lubricants still must be cleaned.
     Response:  The EPA has noted the clarifications provided
by commenter IV-D-40.  However, since the promulgation
preamble does not contain the background information contained
in the proposal preamble, these corrections are acknowledged
here.
2.2.4  New Technologies
     Comment:  Four commenters  (IV-D-05; IV-D-21; IV-D-40;
IV-D-51) addressed EPA's position on the new solvent cleaning
technologies.  One commenter (IV-D-21) questioned why the EPA
requested comments on new technologies since the EPA is
mandated by the statute to establish a standard that is
achieved in practice, not a standard that is "under

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development" at this time.  The conunenter indicated that new
and innovative technologies may be addressed when emission
reductions are confirmed as equivalent and achievable in
practice.
     One commenter (IV-D-40) recommended that any decision to
require new or alternative technologies for specific
applications should be subject to public review and comment
prior to finalization of the regulation.
     Two commenters (IV-D-05; IV-D-51) requested that the rule
be expanded to allow owners or operators using vacuum solvent
cleaning machines (which have no solvent/air interface) to
determine their compliance with the rule.  One commenter
(IV-D-05) requested that their company's vacuum degreasing and
cleaning technology be recognized by the EPA as MACT
technology.  The commenter believes that data from operations,
laboratory analysis, and EPA sponsored testing by the Research
Triangle Institute supports their request.  The commenter
feels that the data show that solvent recovery for their
cleaning equipment, not including carbon adsorption, is
96 percent or better.  This translates to a solvent usage of
less than 0.00205 kilograms  (kg) (0.00045 pounds [Ibs]) per
pound of material cleaned.  Additionally, the commenter stated
that, since the equipment is "closed-loop," the actual
emissions are "zero."  The commenter stated that since their
cleaning system and its technology are not mentioned in the
regulations, its installation would require extensive, and
expensive alternative testing detailed in § 63.465 through
§ 63.467 of the proposed rule.  The commenter also stated that
because their technology is not included in the definition
under § 63.461 or the applicability statement of § 63.460, the
proposed rule will discourage the use of their equipment.
     Another commenter  (IV-D-51) stated that vacuum degreasers
emit much less solvent than traditional equipment.  The
commenter  (IV-D-51) stated that these machines are too
expensive for general use throughout the commenter's
manufacturing areas, but they are well suited for specific

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applications because of their cleaning effectiveness and low
emissions.  The commenter requested that the rule be more
clearly written to allow the use of this type of equipment.
     Response;  The EPA requested comments on new technologies
to validate that there were no existing new technologies (in
practice) that should be included as part of the MACT
analysis.  As stated in the proposal preamble, because of the
lack of data, and the developmental nature of these new
technologies the EPA has not included them in the selection of
MACT.  A technology can only be included in the MACT floor
determination if it is being used in practice in industry.
       The proposed and final standards allow the use of new
technologies where they can be demonstrated to be equivalent
to the MACT control levels delineated for each subcategory.
An owner or operator of a vacuum-to-vacuum or chamber cleaning
machine should be able to comply with the overall solvent
emission limit.
     In order to more easily allow vacuum-to-vacuum and
chamber cleaning machines to determine compliance with the
rule, a table that provides emission equivalency limits for
these cleaning machines was added to the alternative standard
in the final rule.  The table was developed by identifying the
relationship between the cleaning capacity and the solvent/air
interface area for an open top vapor cleaning machine.  This
relationship was then used to equate the cleaning capacity
volume of a solvent cleaning machine without a solvent/air
interface area to a solvent/air interface area.   This table
will enable cleaning machines that do not have a solvent/air
interface to determine their 3-month rolling emission
compliance requirement limit.
2.2.5  Fugitive Emission Controls
     Comment:  One commenter (IV-D-40) stated that room
enclosures should be considered as an effective means to
collect fugitive emissions and potentially reduce worker
exposure.  The use of an enclosure may be the only way to
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reduce drafts at the top of the freeboard area of the cleaner
to the levels proposed by the EPA.
     Response;  In the equipment standard, an enclosure is an
acceptable method of achieving a RRD.  A cleaning machine that
is in an enclosure with the emissions vented to a regenerative
carbon adsorber should be able to comply with the alternative
standard.
2.3  REGULATORY ALTERNATIVES
     Comment:  One commenter (IV-D-04) was concerned that the
proposed NESHAP standards for halogenated solvent cleaning
machines were less stringent than the EPA's Model VOC RACT
guidelines for Solvent Metal Cleaning.  The commenter
suggested that the NESHAP be at least as stringent as the RACT
regulations and that the following requirements be included in
the proposed standards:
      (1)  Degrease only materials that are neither porous nor
absorbent.
      (2)  Repair solvent leaks immediately, or shut down the
degreaser.
      (3)  Hold parts in the vapor zone at least 30 seconds or
until condensation ceases, whichever is longer, and allow
parts to dry within the degreaser for at least 15 seconds or
until visually dry, whichever is longer.
      (4)  Use no ventilation fans near the degreaser opening,
      (5)  Provide a permanent, conspicuous label summarizing
the operating procedures.
     Response:  The EPA does not agree that the NESHAP is less
stringent than the EPA's Model VOC RACT guidelines for Solvent
Metal Cleaning.  Equipment control requirements are more
stringent in the NESHAP.  For example, an increased freeboard
ratio requirement for OTVC's in the NESHAP is 1.0, whereas it
is 0.75  in VOC RACT guidelines.  In addition, the NESHAP work
practice reporting and recordkeeping requirements better
assure emissions reductions than the EPA's RACT guidelines.
The NESHAP has included work practice requirements in the rule
that  control emissions analogous to some of those controlled

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by RACT requirements cited by the commenter (e.g.,  RRD
requirement versus ventilation fan restriction).   The final
rule has been amended to include a ban on cleaning of
materials such as sponges, fabric, wood, and paper products.
2.3.1  MACT Floor
     Comment;  Three commenters (IV-D-09; IV-D-33;  IV-D-42)
discussed the Agency's overall approach to establishing the
MACT floor for the proposed rule.  One commenter (IV-D-09)
agreed with the EPA's approach to setting MACT for this
category of HAP emitting equipment.  One commenter (IV-D-33)
stated that they were unable to determine how the EPA
calculated the values used for the MACT floor.  The commenter
suggested that the EPA clearly define their approach in
calculating the floor and the MACT standard.  One commenter
(IV-D-42) stated that a discussion of the specific
considerations for the MACT floor determinations should be
added to the preamble.
     Response;  The proposal preamble (58 FR 62566) for the
halogenated HAP solvent cleaning machine source discussed that
the MACT floor was calculated based on the emissions
limitations achieved by the average of the best performing
12 percent of existing cleaning machines.  Specifics regarding
the MACT floor determination for the halogenated solvent
cleaner NESHAP are documented in a memo entitled, "MACT floor
determination for solvent cleaning NESHAP."  This memorandum
was submitted to the docket prior to proposal.  This memo can
be accessed through Air Docket Number A-92-39, Document
Number II-B-21.
     Comment;  One commenter (IV-D-36) stated that by
calculating the MACT floor by averaging the upper 12 percent
of the solvent cleaning machines, the EPA has raised the MACT
floor above the 88th percentile.  The commenter stated that
the EPA has taken an overly restrictive view and narrowly read
the MACT floor requirements of the Act.  The commenter stated
that the statute does not require averaging of the emissions
limitations achieved by the best performing halogenated

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solvent cleaning machine sources above the 88th percentile.
The commenter stated that the Act requires averaging of the
halogenated solvent cleaning machine test results before
plotting them by their relative control efficiency in order to
determine an "average" measurement for a particular process.
The commenter stated that the EPA's means of calculating the
MACT floor may not establish a floor that is related to any
particular technology.  The commenter recommended that the EPA
set the MACT floor at a control efficiency that is at the
88th percentile.
     Response;  The EPA does not agree with the commenter's
argument that the MACT floor should be set at the 88th
percentile and does not agree that it has taken an overly
restrictive view of the MACT floor requirements.
     Section 112(d)(3) of the Act provides that:
     Emissions standards promulgated under this subsection for
existing sources shall not be less stringent than
     (A)  the average emission limitation achieved by the best
performing 12 percent of existing sources ... 42 U.S.C.
7412(d)(3).  The minimum level of stringency defined by this
language has come to be known as the MACT floor.  In several
Federal Register notices proposing MACT standards the EPA has
solicited comment on the appropriate interpretation of section
112(d)(3)(A).  Two interpretations were discussed   Under one
interpretation, the EPA  would look at emission limitations
achieved by  each of the best performing 12 percent of existing
sources, and average those limitations.  "Average" would be
interpreted  to mean a measure of central tendency such as the
arithmetic mean or median.  Under the second interpretation,
the EPA would look at the average emission limits achieved by
each of the  best performing 12 percent of existing sources,
and take the lowest.
     The EPA believes that the first interpretation is a
better reading of section 112  (d)(3)(A) than the second.  A
detailed discussion of the reasons for this position are
contained in a Federal Register notice relating to the

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Hazardous Organic NESHAP (HON) MACT standard, signed by the
Administrator on May 27, 1994 and published on June 6,  1994
(59 FR 29196).   In summary, that notice states that the most
natural reading of the statutory language would have the EPA
first determine the emission limitations achieved by sources
within the best performing 12 percent, and then average those
limitations.  In addition,  if Congress had intended the second
interpretation, language other than that actually used in
section 112(d)(3)(A) would have been far more natural.   For
example. Congress could have said that standards must be no
less stringent than "the emission limitation achieved by all
sources within the best performing 12 percent."
     Therefore, consistent with the position taken in the
final HON MACT standard, the EPA has determined the MACT floor
for today's rule on the basis of the first interpretation of
the floor language of the statutes discussed above.
     Comment:  One commenter (IV-D-42) stated that there are
sources that are better controlled than the general
requirements of the rule and that new sources should be
required to meet this level of control.
     Response:   Based on data provided to the EPA on current
existing in-practice controls at proposal there were no
combinations of controls that achieved an emission reduction
greater than the new source MACT in this rule.  The EPA
evaluated new emerging technology prior to proposal.  However,
as discussed in the preamble, these technologies are still
under development and insufficient data are available to
include these technologies in the MACT analysis.  Since the
EPA has not received sufficient data to corroborate that there
are existing sources that are better controlled than the
general requirements of the rule, the EPA has not based the
final rule on these new technologies.  The flexibility of the
final rule, however, allows the use of new technologies where
they are demonstrated to be equivalent to the control levels
of MACT for each solvent cleaning machine subcategory.
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     Comment:   Several commenters (IV-D-21; IV-D-31; IV-D-32;
IV-D-35) stated a concern that the EPA did not determine MACT
through an analysis of emission control data achieved by
existing, operating sources "in practice."  Two commenters
(IV-D-21; IV-D-31) indicated that the vendor control
efficiency and laboratory data used to establish the MACT
"floor" is not necessarily representative of the control
levels achieved by the industry in practice.  One commenter
(IV-D-21) warned that vendor's claims may be based upon the
performance of control equipment that is new and/or used under
the best possible conditions.  Since degreasing operations are
diverse in design and age, it is unlikely that the information
analyzed is representative of what is "achieved in practice"
by the degreasing industry as a whole.  Another commenter
(IV-D-32) stated that other control combinations might
represent preferred methods of control.  The commenter
(IV-D-32) recommended that the EPA revisit the data and
analytical methods used to establish the selection of MACT and
repropose the rule.
     Response;  The EPA solicited data through section 114
questionnaires at two different times, at the NAPCTAC meeting
in November 1992 prior to proposal, and in the NESHAP
proposal.  The EPA did not receive any new data.  Therefore,
the EPA used the best and only available data in their
analysis, which are vendor data and data obtained on cleaning
machines studied under controlled conditions.  The EPA does
not require that a performance level be met.  An owner or
operator of a cleaning machine can meet the equipment standard
to comply with the regulation.
     2.3.2  MACT versus GACT
     Comment;  Five commenters (IV-D-10; IV-D-21; IV-D-31;
IV-D-33; IV-D-35) stated that the EPA should support the
promulgation of GACT standards for area sources.  One
commenter  (IV-D-10) stated that the data collected by the EPA
in preparing the NESHAP does not appear to support
classifying/designating small and medium cleaning machines as

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major sources and, therefore, subject to MACT.  The commenter
further elaborated that there are a number of economic,
technological, or feasibility issues that warrant the use of
GACT rather than MACT for small and medium batch vapor
cleaning machines.  Another commenter (IV-D-35) stated that
setting GACT standards for area sources would reduce the
reporting burden on small businesses.
     One commenter (IV-D-34) stated that small businesses,
operating smaller solvent cleaning equipment, would be
unfairly burdened with expenses aimed at controlling emissions
that are inherently less severe than emissions from larger
equipment.  The commenter recommended that small and medium
vapor degreasers should be designated as area sources.
Another commenter (IV-D-40) recommended that small vapor'
cleaners be designated as area sources.  This would allow the
EPA to forego a residual-risk analysis on these sources and
would allow the EPA to specify a lesser level of control for
these sources.  One commenter (IV-D-21) requested that the
major source versus area source emission determination and
technical standard classification (MACT versus GACT) be
distinguished separately.  The commenter (IV-D-21) then
requested that the residual risk analysis apply to only the
"major" emission sources.
     One commenter (IV-D-40) stated that because many small
cleaners are used to a very limited degree, the need for
flexibility in regulatory compliance in this category is
greater than elsewhere.  The commenter stated that reducing
the required level of control from 60 to 50 percent of
uncontrolled emissions for small sources reduces the cost of
the regulation by only 5 to 10 percent, but increases the
number of available control equipment combinations from 4 to
18 for existing small sources and from 4 to 28 for new small
sources.
     Another commenter (IV-D-33) disagrees with the position
that if the same control limit is determined for MACT and
GACT, the standard should default to GACT in order to avoid

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residual risk requirements.  The commenter stated that the
purpose of GACT is to require less stringent controls on
smaller sources that pose less of a threat to public health
and the environment and would be subject to severe economic
impacts as a result of complying with the federal regulation.
     Another commenter (IV-D-35) stated that the EPA should
consider the impact of a MACT or GACT designation on the
ability of State and local agencies to implement this
regulation.
     Response:  The EPA considered establishing GACT for
solvent cleaning machines.  As discussed in the proposal
preamble, there is no reason for the use of GACT as opposed to
MACT for solvent cleaning machines.  The use of GACT as
opposed to MACT for area sources is not required by the Act.
A GACT approach might be warranted if significant adverse
economic impacts are expected on small sources, or if there is
a technological limitation to installing a control device on
smaller emission sources.  Although a number of halogenated
HAP solvent cleaning machines are expected to be located at
small businesses, the use and operation of these cleaning
machines does not represent a significant portion of the
operating costs for these businesses (0.1 to 9.7 percent).
Furthermore, adopting GACT standards for halogenated HAP
cleaners would not reduce the reporting burden on small
businesses.  The reporting requirements are based on what is
needed to determine compliance.  No data were provided that
supported regulating area sources at a lesser control level
than major sources.  Therefore, MACT has been maintained in
the final rule for all of the halogenated solvent cleaner
NESHAP subcategories except for batch cold cleaning machines,
as proposed.
     A MACT or GACT determination is not made based on the
impact that a particular determination would have on the
regulatory agencies.  However, the regulatory agency burden of
this rule was evaluated.  The EPA concluded that the
regulatory agency burden was not unreasonably burdensome given

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the potential emission reductions that would result from the
implementation of the rule.
2.3.3  Regulatory Alternatives
     Comment:  One commenter (IV-D-42) stated that there are
some requirements that are unnecessarily burdensome for
existing sources and cannot be justified on a
cost-effectiveness basis.  To address this, the commenter
recommended that the rule present separate requirements for
new and existing sources.
     Response;  The EPA's analysis did not confirm that there
would be an unnecessary burden for existing sources as a
result of this rule.  Furthermore, the commenter (IV-D-42) did
not identify the specific requirements that they believed were
unnecessarily burdensome for existing sources.  When
conducting the regulatory alternative analysis, the EPA
evaluated new and existing solvent cleaning machines
separately.  The EPA chose the most stringent regulatory
alternative for each solvent cleaning machine source
subcategory for both existing and new cleaning machines, after
considering emission reduction, cost, economic, and other
environmental impacts.  The impacts of the rule on both
existing and new sources were determined to be reasonable.
The proposal MACT selection is discussed further in
section VI.E., Selection of Maximum Achievable Control
Technologies of the proposal preamble (58 FR 62566).
     Comment;  Two commenters (IV-D-20; IV-D-29) stated that
the regulation would be much easier to implement and enforce
if the EPA determined which additional requirements were
necessary to meet their objectives.  The commenters believed
that the EPA should further evaluate the requirements imposing
a higher capital expense to determine if the reduction of
hazardous air pollutants outweighs the costs.  The EPA could
differentiate between small and large cleaning machines by
applying only these more extensive requirements to large batch
vapor or in-line solvent cleaning machines.  The commenters
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supported clearly enforceable specific requirements that have
been shown to significantly reduce emissions.
     Response:  The EPA is required to set MACT standards for
halogenated solvent cleaners that requires "the maximum degree
of reduction in emissions of the HAP . .  . that the
Administrator, taking into consideration the cost of achieving
such emission reduction, and any nonair quality health and
environmental impacts and energy requirements, determine is
achievable for new or existing sources in the category or
subcategory to which such emission standard applies ..."
[the Act section 112(d)(2)].  In complying with this
requirement, the EPA evaluated the requirements proposed under
the NESHAP, including the cost-effectiveness [cost in $/year/
reduction of HAP (Mg/yr)] of the equipment standard options
when determining MACT.  Further, the EPA has incorporated a
number of options to comply with the NESHAP to allow an owner
or operator of a cleaning machine the flexibility to choose
the most cost-effective or feasible control option.  The
cost-effectiveness analysis considered capital costs,
monitoring costs, and reporting and recordkeeping costs
associated with each of the options.  The EPA has re-evaluated
the monitoring, reporting, and recordkeeping enforcement
requirements included in the proposed rule and has reduced
them where possible while still ensuring that the MACT
established for halogenated HAP batch vapor and in-line
cleaning machines, and GACT established for halogenated HAP
batch cold cleaning machines are met.
     2.3.3.1  Emission estimates
     Comment;  One commenter (IV-D-24) stated that, due to the
decline in the number of halogenated carburetor cleaning
machines, the total nationwide emissions rate is well below
the 1,400 Mg/year estimated in the proposal.
     Response;  No data were submitted that indicated that
there were less carburetor cleaning machines or emissions than
the estimate presented  in the proposal preamble.  However,
even if emissions from these sources were estimated to be

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significantly less, the control requirements in the rule for
these cleaning machines would not change.
     2.3.3.2  National costs
     Comment:  One commenter (IV-D-37)  asked whether the EPA
included the replacement of solvent required by § 63.464(b)(1)
of the proposed rule in the estimated national costs of the
proposed standards.
     Response:  The intent of § 63.464(b)(l) of the proposed
rule was not to replace the solvent every month, but to assure
that the solvent is clean.  Clean liquid solvent was defined
in the proposed regulation to include "solvent that has been
filtered, skimmed, and/or distilled to remove soils
(e.g., skimmed of oils or sludge and strained of metal
chips)."  The EPA has revised the final definition of "clean
liquid solvent" to allow for additional methods to ensure that
the solvent is clean, and revised § 63.464(b)(l) to clarify
that clean liquid solvent does not mean only virgin solvent.
     2.3.3.3  Number of cleaning machines
     Comment;  One commenter (IV-D-40)  stated that the EPA's
regulatory analysis assumes a lower level of control for
existing small and very large vapor cleaning and in-line
cleaning machines than the levels used in the calculation of
the total number of cleaning machines outlined in the May 26,
1993 memorandum titled, "Estimate of the Number of Halogenated
Solvent Cleaners" (Docket Number A-92-39,  Document
Number II-B-18.
     Response;  The EPA recognizes that the level of control
used for existing small and very large vapor cleaning and
in-line cleaning machine levels differ from the levels used in
the estimate of the total number of cleaning machines outlined
in the May memo.  This difference is because the refined
control levels used in the regulatory analysis were developed
after the number of cleaning machines was estimated.  The
estimated number of batch vapor cleaning machines was not
revised because the EPA determined that the decision would not
change if these numbers were recalculated.  The differing

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control levels have negligible effects on the number of batch
vapor cleaning machines (16,100 versus 16,400).  The number of
in-line cleaning machines is nearly half the number of
machines (4,090 versus 8,080) given the control levels used in
the EPA's regulatory analysis as compared with those used in
the estimate of the number of in-line cleaning machines.  This
difference would not affect the regulatory options chosen
because the incremental cost-effectiveness is not affected by
the number of cleaners.  The reduced number of in-line
cleaning machines would, however, affect (reduce) the national
HAP emission reduction estimate associated with control.
Since the differing control levels would not affect the
regulatory options chosen, the estimated number of cleaning
machines used for the regulatory analysis was not revised.
     2.3.3.4  Energy impacts
     Comment:  One commenter (IV-D-54) stated that the EPA
should recognize that increased energy use (for additional air
pollution control devices) can result in secondary air quality
impacts.
     Response:  The EPA evaluated the increased energy use
that would potentially occur as a result of the rule and
concluded that the increased energy impacts would be
negligible, while the primary benefits of the rule would be
significant.  Because the increased energy impacts were
considered to be negligible, it was determined that it was not
necessary to analyze the secondary air quality impacts that
might occur from increased energy use.
     2.3.3.5  Environmental impacts
     Comment;  Two commenters (IV-D-03; IV-D-06) commented on
potential water contamination due to the proposed standards.
One commenter  (IV-D-06), in reference to section V.B.  Water
and Solid Waste of the proposal preamble, stated that the
increased use of refrigerated condensers will cause adverse
water impacts.  This would result from an increase in the
amount of water condensed from the air blanket.  It is
possible that the increased amount of water condensate will

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hasten solvent decomposition due to acidification, thereby
shortening the solvent life and necessitating more frequent
solvent disposal.  After separation, this water will
presumably be discharged in the sanitary sewer.  The commenter
(IV-D-06) added that although the amount of halogenated
solvent thereby discharged to publicly owned treatment works
(POTW's) is probably small, these compounds are priority
pollutants regulated under water regulations and may be a
water quality concern.  Furthermore, if the EPA proceeds with
development of a POTW MACT air emission standard in 1995,
local sewer authorities may respond by banning water separator
discharges to the sanitary sewer in an effort to achieve
source reduction as an alternative to installing emission
controls.  The EPA's POTW MACT workgroup should be consulted
regarding possible impacts of the solvent cleaning machine
standard on POTWs, and possible interaction between the
solvent cleaning machine MACT and any future POTW MACT
standards.
     Another commenter (IV-D-03) stated that the EPA should
not recommend that users pour decanted water that may be
contaminated with halogenated solvents down the sewer.  The
commenter further stated that the EPA has recently ruled that
aqueous-based hazardous waste (such as halogenated solvents
dissolved in water) can be evaporated without the requirement
for a treatment permit.  However, since the EPA has not set
standards for such evaporators,  a plastic tub may be used as
the evaporator and the separator water can be evaporated as it
is generated, preventing further sewer contamination.
     Response:  The EPA has not received any data to support
the claim that refrigerated condensers will hasten solvent
decomposition.  Furthermore, the proposed and final NESHAP do
not recommend that users pour decanted water that may be
contaminated with halogenated solvent down the sewer.  The EPA
allows for the use of separator water evaporators if their
design meets the definition of a "wastewater treatment unit"
under the Resource Conservation and Recovery Act (RCRA).

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Tanks that meet the definition of a wastewater treatment unit
are exempt from RCRA permitting under 40 CFR sections
264.1(g)(6) and 270.l(c)(2)(v).  Therefore, these units would
not require RCRA permits,  provided they meet the criteria to
qualify as wastewater treatment units outlined in 40 CFR
section 260.1.
     Under the definitions and criteria contained in RCRA, a
plastic tub that is not designed to contain an accumulation of
hazardous waste would not be considered an acceptable
treatment unit for decanted water.  The definition of
wastewater treatment unit consists of three parts enumerated
at 40 CFR section 260.10.   First, the evaporator unit must
meet the definition of "tank" or "tank system" also found in
section 260.10.  Second, the evaporator must be receiving and
treating or storing an influent wastewater (or wastewater
treatment sludge) that is a hazardous waste, which includes
all halogenated HAP.  Finally, the facility must be subject to
sections 307(b) or 402 of the Clean Water Act; this includes
wastewater treatment units at facilities that  (1) discharge
treated wastewater effluent into surface waters or into a
Publicly-Owned Treatment Works (POTW) sewer system, or  (2)
produce no treated wastewater effluent as a direct result of
such requirements.  Tank as defined in the RCRA regulation,
means a stationary device, designed to contain an accumulation
of hazardous waste, which is constructed primarily of
nonearthern materials  (e.g., wood, concrete, steel, plastic)
which provide structural support.  Tank system means a
hazardous waste storage or treatment tank and  its associated
ancillary equipment and containment system.
     Comment;  Two commenters  (IV-D-12; IV-D-27) discussed the
impacts of CAD's.  One commenter  (IV-D-12) stated that  some
CAD systems that use steam injection for the regeneration of
carbon beds can be provided with special water treatment
systems designed to minimize organic contact from the effluent
water prior to disposal.  These systems minimize the potential
impact of CAD's on water quality.

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     According to one commenter (IV-D-27) ,  CAD's do not
produce substantial amounts of contaminated wastewater.  This
is due to the fact that the inlet air from a properly operated
lip exhaust on a degreaser is relatively dilute and the CAD
desorption cycle is much longer than those controlling other
processes, such as dry cleaning.  In addition, many facilities
reclaim the solvent from the wastewater and recycle it to the
process.
     Response;  The EPA acknowledges that CAD's do not
adversely impact water quality if the unit is properly
operated and solvent is reclaimed.  The EPA has added CAD's to
the list of control options in the equipment standard.
2.4  BENEFITS ANALYSIS/ECONOMICS
     Comment:  One commenter (IV-D-33) does not support EPA's
use of a cost-benefit analysis to justify a more stringent
MACT standard than the minimal floor identified in the
analysis.
     Response;  The proposed standard was selected based on
the EPA's analysis of the potential emission reduction, and
the cost, economic, and other environmental impacts associated
with differing levels of control.  The EPA did not use the
cost-benefit analysis in selecting the MACT standard.  The EPA
did a preliminary benefits analysis to see if a further
cost-benefit analysis might aid the EPA in the selection of
MACT.  It was determined that a full cost-benefit analysis was
not warranted.
     Comment;  Two commenters (IV-D-31; IV-D-54) stated that
the reduction in health risk was overestimated in the benefits
analysis.  One commenter (IV-D-54) felt that, since
halogenated solvent cleaners are widely distributed, the
average national population density should have been used
instead of the population density of major cities.  Another
commenter (IV-D-31) stated that the EPA should discard the
current benefits analysis, design a protocol with public
comment or outside peer review,  and recalculate the benefits.
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     Response;  The EPA contends that the reduction in health
risk is highly uncertain.  The benefit analysis did not assign
a subjective value to human life.  The analysis values small
reductions in risk using empirical studies of the relationship
between wages and risks.  Constructing a model city with
national average population density would be unlikely to
reduce the uncertainty for the risk or benefit analysis.
Since further refinement of the risk or benefit analysis would
be resource intensive and unlikely to reduce the uncertainty,
the EPA has chosen not to pursue an analysis beyond the risk
characterization already performed.
     Comment:  One commenter  (IV-D-31) stated they were
concerned and disagreed with the EPA's decision to count the
reduced solvent usage as an economic benefit to the rule.
They suggested that the EPA only consider the direct costs and
benefits, because one company's "savings" is another company's
"loss."
     Response:  Although solvent producers would experience a
reduction in certain solvent product sales, they would also
reduce production of those solvents no longer in demand.
Initially, producers could experience a reduction in revenue
exceeding the reduction in production costs for those solvent
product lines no longer in demand.  This reduction would
result from adjustment difficulties associated with certain
production costs (particularly capital costs).  However,
within a short period of time, a company should experience a
reduction in production costs that would equal the reduction
in revenues for those solvent product lines.  Once these
equilibrate, the company profits would be minimally affected.
Therefore, the reduced solvent usage attributable to the
regulation would cause little change in profits for solvent
producers in the long run.  Recovery of revenue through other
chemical product sales could also offset any reduced revenue
from reduced solvent product  line sales.  Therefore, the final
rule analysis maintains reduced solvent usage as an economic
benefit.

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     Comment:  Several coirunenters (IV-D-12; IV-D-27; IV-D-33)
were concerned that the EPA has not adequately evaluated the
economic burden of this standard on small businesses.  One
commenter (IV-D-33) said that annual costs may not be
sufficient to determine the impact of this regulation,
particularly on small businesses that do not have a large
profit margin.  The commenter suggested that it would be
helpful for the EPA to evaluate the costs for each subcategory
based on whether it presently has controls or is uncontrolled.
     Response;  The EPA's economic impacts analysis focused on
businesses that own and operate small and medium-sized solvent
cleaning machines.  The impacts were small enough that a
Regulatory Flexibility Analysis (5 U.S.C. 601 et seq.> was not
warranted.
     The EPA's economic analysis (Docket No. A-92-39,
Document No. II-A-14) included more than an estimate of annual
costs to determine the possible impacts to affected
businesses.   The analysis also examined the ability of a small
firm to obtain capital to finance additional emissions
control.  Since the capital costs incurred as a result of
investment in control equipment needed for small businesses to
meet the standard was less than 10 percent of the businesses1
total assets in all 39 affected SIC codes, it was concluded
that the assets and earnings of small businesses would not be
so adversely affected by the rule that they would require
outside financing.
     The EPA also evaluated whether there was a potential for
small businesses to close because of the proposed rule.  The
EPA's analysis was based on earnings impacts under a
worst-case scenario.  This scenario assumed that affected
businesses completely absorbed the entire cost of control and
could not recover control costs through price increases on
their products.  This analysis indicated that facilities in
only two of thirty-nine standard industrial classification
(SIC) codes were at risk of closing as a result of the burden
of complying with the regulation.  This analysis also

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indicated that the number of possible closures in those SIC
codes is small (less than 3.4 percent).
     Comment:  One Commenter (IV-D-50)  stated that,  even
though the EPA's benefit analysis estimated that halogenated
solvent cleaning machines cause as many as six cancer cases a
year, they believe halogenated solvents actually provide
health benefits.  The commenter stated that the aircraft
industry depends on halogenated solvents for proper cleaning.
The commenter pointed out that some alternatives to
halogenated solvents are flammable, and others are being used
without adequate testing and experience.
     Response;  The EPA acknowledges that there may be health
benefits associated with the use of halogenated HAP solvents
as compared with some halogenated solvent alternatives.
However, the benefits in health are uncertain and depend on
the chosen compliance alternative.  The EPA could not estimate
the benefits of halogenated HAP solvent use compared to an
unknown chosen alternative.
     Comment;  Two commenters (IV-D-12; IV-D-27) questioned
whether the economic impact of the proposed standard was
justified.  One commenter  (IV-D-12) was concerned that
existing equipment owners are required to upgrade existing
equipment to the proposed standards.  The major concern was
that the industry is comprised mostly of small businesses that
would not be able to meet the financial obligation to make
these retrofits, monitoring, and other requirements as listed
in the proposed ruling and would therefore affect the economy
of the United States, and increase the unemployment ratios
across the nation.
     One commenter  (IV-D-27) was concerned that the costs
associated with installing mechanical hoist systems in
conjunction with the equipment identified under the control
options would be too great a financial strain for very small
businesses.  The commenter believes that the requirements for
control devices should be associated with decreasing health
risks.  The  commenter would like to see an economic analysis

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illustrating the impact of the proposed rule on the small
businesses.
     Response;  As mentioned in a previous response, the EPA's
economic analysis examined the ability of a small firm to
obtain capital to finance additional emissions control.
Through this analysis it was determined that the assets of
small businesses would not be so adversely affected by the
rule that they would require outside financing.
     The EPA also evaluated whether there was a potential for
small businesses to close because of the proposed rule.  The
EPA's analysis evaluated impacts on earnings impacts under a
worst-case scenario.  This scenario assumed that affected
businesses completely absorbed the entire cost of control and
could not recover control costs through price increases on
their products.  This analysis indicated that businesses in
only two of thirty-nine standard industrial classification
(SIC) codes were at risk of closing as a result of the burden
of complying with the regulation.  This analysis also
indicated that the number of possible closures in those SIC
codes is small (less than 3.4 percent).  The EPA's economic
analysis for the proposed rule is available for public viewing
through the docket.  This document is entitled, "Economic
Impact Analysis of the Degreasing NESHAP," Docket No. A-92-39,
Document No. II-A-14.
     Comment;  One commenter (IV-D-12) disagreed with the
statement in the preamble that the economic impact would be
minimal if the proposed NESHAP is promulgated.  They felt that
there would be a major impact as a result of owners and
operators switching to aqueous cleaners and other alternative
cleaning technologies due to the high cost and reporting
burdens associated with the standards.
     Response:  The EPA's economic analysis did not quantify
the impacts of switching from the use of halogenated solvents
to aqueous or other alternative cleaning technologies.  There
is little stimulus to substitute halogenated solvent cleaning
machines with aqueous cleaning machines or other alternative

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cleaning technologies.  This is because there would only be a
small increase in annual costs associated with controlling
existing machines and because businesses would generally be
able to finance the necessary capital investments.
     Comment:   Two commenters (IV-D-20; IV-D-29)  asked that
the EPA evaluate the impact of the NESHAP on regulatory
agencies and determine whether the cost of enforcement is
worth the HAP reduction.
     Response;  The EPA believes that the halogenated HAP
solvent reduction is worth the cost of enforcement on
regulatory agencies.  Under the Paperwork Reduction Act, 44
U.S.C. 3501 et sea.. information collection requirements in
the proposed rule were evaluated.  The only costs that
regulatory agencies will incur are costs associated with the
review of reported information.  The annual cost incurred by
regulatory agencies was estimated to be $1.5 million per year
for the first 3 years.  The regulatory agency cost of the
regulation will decrease by approximately 50 percent after the
first 2 years of implementation.  These cost estimates include
time for reviewing instructions, searching existing data
sources, gathering and maintaining the data needed, and
completing and reviewing the collection of information.
2.5  PROPOSED STANDARDS
     Comment:  Several commenters (IV-D-09; IV-D-13; IV-D-27;
IV-D-29; IV-D-30; IV-D-35; IV-D-50)  discussed the complexity
and flexibility of the proposed standards.  One commenter
(IV-D-09) commended the EPA for including multiple alternative
methods for achieving MACT.  Another commenter (IV-D-50)
stated that they generally agree with the proposed standards
for batch vapor degreasers and feel that they are appropriate.
One commenter  (II-D-13) requested that the EPA consider
incorporating more  flexibility into the proposed NESHAP to
allow for advances  in emission control technology for those
operations that cannot be switched to aqueous cleaners and to
encourage the development and use of new cost-effective
emission reduction technologies.  Specifically, the commenter

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recommended that the EPA include a provision in the final rule
that allows new equipment that is designed to meet or exceed
the equivalent emissions limitation of the proposed standard.
     Three of the commenters (IV-D-27; IV-D-29; IV-D-35)
suggested that the EPA should reduce the flexibility of the
rule.  One commenter (IV-D-35)  recommended that the EPA
endorse a single preferred method of control for this source
category, followed by acceptable alternatives that can be
adopted by the source operator.  Another commenter (IV-D-29)
recommended requiring a freeboard refrigeration device or
super-heated vapor, a biparting cover (batch cleaner only),
and the automated parts handling system at a maximum speed of
3.3 mpm (10.8 fpm) (batch cleaner only)  for all machines
subject to this rule.  One commenter (IV-D-27) recommended
that the most effective control methods be identified as
standard control requirements,  with the stipulation that other
options would be allowed if equivalency could be demonstrated.
     Response:  The EPA evaluated the relative benefits of a
single compliance alternative or flexible alternatives.  The
EPA concluded that flexibility was warranted because this
approach reduces owner or operator burden by allowing a
facility to adopt the most cost effective control strategy for
their specific situation.  The high level of compliance
flexibility found in the proposed rule has been increased in
the final rule.  The EPA included in both the proposed and
final rule, a provision that allows new equipment that is
designed to meet or exceed the equivalent emissions limit to
comply with rule.  The EPA has also added a means for owners
or operators of solvent cleaning machines that do not have a
solvent/air interface to determine compliance with the final
rule.  The EPA has also included additional control
combinations in the final rule.  The EPA retains the position
of flexibility of compliance options in the final rule in
order to promote innovation and to minimize the burden for
owners and operators of existing halogenated solvent cleaning
machines.

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     Comment;   One commenter (IV-D-34)  was concerned that the
EPA has not sufficiently addressed the physical differences
between the solvents generally used in degreasing:   PCE,  TCE,
and MC.  These differences can result in significant variances
in emission rates.  The commenter believes that the EPA's data
were derived from tests using TCA and thus the NESHAP
penalizes operations that use PCE and MC.  The commenter
pointed out that this discrimination is apparent not only in
the emission limits, but in the requirements associated with
SHV and freeboard refrigeration, which are more difficult to
operate with PCE.
     Response;  The EPA used data from multiple HAP's (MC,
PCE, TCA, and TCE) when looking at the efficiencies of the
various controls.  However, the EPA has not developed separate
standards for different solvents in this rule.  Based on
available data, and as stated in the BID, the EPA concluded
that halogenated HAP emissions are more dependant on operating
parameters and control devices than on the solvent used.
     The EPA has modified the requirements for SHV and FRD in
the final rule.  The SHV requirement has been changed to
require the solvent vapor to be heated to at least 10 degrees
Fahrenheit above the solvent's boiling point.  The FRD
requirement has been changed to require that the temperature,
measured at the center of the air blanket, shall be no greater
than 30 percent of the solvent's boiling point.  The EPA
believes that these changes will make the rule more sensitive
to the differences between solvents.
     Comment;  One commenter (IV-D-18)  requested that
"Continuous web cold cleaning" be evaluated separately and
emission limits or performance standards be developed for that
subgroup.  They based their request on their continuous web
cold cleaning machines, which have PCE as a cleaning agent.
Although they believe their existing emission controls reflect
the best available emission control technology for their
machines, they have emission levels two to three times higher
than the proposed limits.  Their cleaning machines are

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covered, the entrance and exit openings are approximately
6 inches high, have an exhaust system, carbon adsorption beds,
and air stripper for condensate from regeneration of carbon
adsorber beds, and use squeegee rolls to remove residual PCE
from sheet metal prior to exiting the cleaning chamber.
     Response;  The EPA acknowledges that the "continuous web
cleaning process" fits the description for an existing in-line
cleaning machine, covered under the halogenated solvent
cleaner NESHAP.  Under the final rule, owners or operators of
existing in-line cleaning machines have the option of
complying with the equipment standard in lieu of the emission
limit.  The equipment standard for existing in-line cleaning
machines allows for four different control combinations in
conjunction with work practices.  The commenter (IV-D-18) can
demonstrate compliance with the equipment standard through
addition of appropriate controls (e.g., increased freeboard
ratio, freeboard refrigeration device, superheated vapor) and
by following appropriate work practices.  The EPA has also
changed the final rule to allow for alternative work practices
to those delineated if equivalent control (e.g., use of
squeegee rolls in lieu of parts orientation and drainage
practices required for parts cleaning) can be demonstrated.
     Comment;  One commenter (IV-D-55) stated that all the
solvent calculation procedures required by §§ 63.462, 63.463,
and the test method of the proposed rule, should be modified
to only address the use and/or emissions of halogenated
solvents that are HAP's.  The calculations should be corrected
by adding a halogenated HAP concentration factor so that only
the actual concentration of halogenated HAP solvent is
accounted for.
     Response:  The calculations in the final rule have been
clarified to indicate that only halogenated HAP solvent should
be included.  This was the intent of the proposed rule.
     Comment;  Two commenters (IV-D-29; IV-D-42) provided
recommended control requirements.  One commenter (IV-D-42)
stated that freeboard chillers are a reasonable alternative to

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increasing the freeboard ratio.  This commenter suggested that
freeboard chillers or carbon adsorber recovery mechanisms be
added to the baseline option requirements in 63.462.
     Another commenter (IV-D-29) recommended that existing and
new batch vapor or in-line solvent cleaning machines meet all
of the following control technology requirements:
     (1)  A cover that is fully closed at all times except
when processing work in the degreaser.  The cover shall be
closed to the maximum extent possible when parts are being
degreased.
     (2)  A freeboard ratio greater than or equal to 1.0.
     (3)  A vapor leveD control device which shuts off the
sump heat if the vapor level rises above the height of the
primary condenser.
     (4)  A device which shuts off the sump heat if the sump
liquid solvent level drops below the height of the sump heater
coils.
     (5)  When equipped with a lip exhaust, a CAD to which all
solvent vapors must be routed.
     Response;  The EPA has not adopted the commenters'
recommended language in the final rule.  The EPA has
determined that multiple compliance options are warranted for
the halogenated solvent cleaning machine source category.
These options accomplish an equivalent or greater level of
control than suggested by the commenter.  Further, the EPA has
included operator training in the proposed and final rule to
ensure that all operators are aware of and comply with the
work practices required to limit emissions from this source.
2.5.1  Equipment Standards
     Comment:  One commenter  (IV-D-49) stated that it is
unlikely that an owner or operator will use the complex
formulas for determining the net efficiency of multiple
control techniques.  In addition, the actual efficiencies of
these control techniques is highly variable, making the actual
emission reduction uncertain.  The commenter added that the
format of the standard, which includes equipment standards

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coupled with work practices, is desirable, but very difficult,
if not impossible, to enforce at the field level.  Therefore,
the commenter suggested that a 50 ppm HAP instantaneous
fugitive emission control standard be added to the rule.
     Response;  The owner or operator that chooses to comply
with the equipment standard is not required to calculate the
net efficiencies of the multiple control techniques.  The
owner or operator is required to follow the work practices,
basic design requirements, and ensure that the solvent
cleaning machine is utilizing one of the control combinations
listed.
     It is true that the control efficiency of a particular
control device can vary under different conditions and
therefore there is a degree of uncertainty with the actual
emission reduction that is achieved.  However, the EPA has
based the control efficiencies of the solvent cleaning machine
controls on the best data available to the Agency.
     The EPA regulatory analysis for the proposed equipment
and work practice standards shows that these compliance
options are technically effective and cost effective means of
achieving halogenated HAP emission reductions.  The monitoring
section of the rule contains the parameters that must be
monitored to ensure the proper functioning of these controls.
The EPA believes that these monitoring procedures are neither
complex nor difficult to enforce.
     The EPA has not set a 50 ppm instantaneous fugitive
emission control standard for solvent cleaning machines in the
final rule.  The statutory authority under section 112 of the
Act is performance based but allows equipment standards under
the following conditions: (1) if the HAP cannot be emitted
through a conveyance device, or  (2) if the application of
measurement methodology to a particular class of sources is
not practicable due to technological or economic limitations.
The control technologies upon which MACT is based would result
in different concentrations, depending upon a number of
factors.  The statutory basis of the standard is technology.

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Furthermore, there is insufficient data to derive accurate
and/or appropriate concentrations for each of the halogenated
solvent cleaner subcategories.
     Comment:   Two commenters (IV-D-31; IV-D-40)  stated that
covers should be used during both idling and downtime.  One
commenter (IV-D-31) recommended that section 63.462(d)(l) be
revised to say:
     "The cover(s) to each solvent cleaning machine shall
     be closed during the idling mode, and during the
     downtime mode unless either the solvent has been
     removed from the machine, or maintenance is being
     performed which requires the cover(s) to be open."
     Response:  The EPA reevaluated the control combinations
between proposal and promulgation based on information
received.  During this evaluation, the EPA concluded that
there is nothing that would prohibit an owner or operator, who
is already required to use a cover during the downtime mode,
from using the same cover during the idling mode.  Therefore,
the EPA has amended the final rule to clearly require that the
cover or equivalent (includes RED) shall be in place during
the idling mode.
     Comment:   Two commenters (IV-D-38; IV-D-42)  were
concerned about the overlap between the NESHAP and existing
State programs.  One commenter (IV-D-38) stated that the.
proposed national standards do not include the concept of
total enclosure and CAD recommended to the commenter by the
Connecticut Department of Environmental Protection.  Another
commenter (IV-D-42) stated that many solvent cleaning machines
in their State have installed CAD systems as BACT to meet
State requirements.  They felt it would be punitive to require
additional controls when these systems control emissions
effectively.
     Response:  Carbon adsorbers have been added to the
control combinations in the equipment standard.  In addition,
enclosures are included in the final rule as a means of
achieving RRD.  All the control combinations in the equipment
standard have been calculated to achieve the MACT level of
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control.  A CAD or an enclosure alone do not achieve the MACT
level of control.  However, an owner or operator complying
with the alternative standard emission limit is not required
to install any specific piece of emission control equipment.
If the owner or operator demonstrates that their cleaning
machine meets the limit using only a carbon adsorber, then
they need not install additional equipment.
     Comment:  One commenter (IV-D-40) stated that several of
the proposed equipment options are not reasonably available to
existing cleaning machines.  For example, if it is not
possible to retrofit batch vapor cleaning machines with
super-heated vapor systems, four of the seven equipment
options proposed for existing large and very large batch vapor
cleaning machines would be unavailable.  Further, the design
of some in-line cleaning machines limits how much the
freeboard ratio can be extended.
     Response;  Vendors of SHV technology have indicated to
the EPA that SHV is currently available for retrofitting onto
existing solvent cleaning machines.  However, the EPA
acknowledges that some of the equipment control options in the
rule are not practical for retrofitting to some existing
cleaning machines.  For this reason, the EPA adopted a number
of equipment options, and provided the idling emission limit
and the overall solvent emission limit standard with which an
owner or operator can choose to comply.
     Comment:  Two commenters (IV-D-21; IV-D-31) recommended
that the language in § 63.462(d)(9) be changed to allow
alternatives to the maintenance practices recommended by the
equipment manufacturers, provided that the alternatives
achieve the same result as the manufacturer's recommendations.
     Response;  The rule allows the use of maintenance
practices other than those recommended by the equipment
manufacturers provided that the owner or operator can
demonstrate, to the satisfaction of the Administrator, that
the same or better results are obtained.
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     Comment:  One commenter (IV-D-41) supported the inclusion
of batch cold cleaning machines in the regulation, provided
that they meet the requirements of South Coast Air Quality
Management District's (SCAQMD's) Rule 1122.  Rule 1122
requires for batch loaded cold cleaners that have:
     (1)  A freeboard ratio of at least 0.5 if they use low
volatility solvents; or
     (2)  A freeboard ratio of at least 0.75 if they use high
volatility solvents or a water cover over the surface of the
solvent if the high volatility solvent has low solubility in
water.
     Response:  The EPA acknowledges that additional equipment
options should be included in the final rule to account for
those batch cold cleaning machines for which a water cover
over the surface of the solvent is impractical.  The EPA has
included a freeboard ratio of 0.75 and a cover, and
remote-reservoir and a cover equipment options in the final
rule.  Work practice requirements have also been added for
these alternatives.
     Comment:  One commenter (IV-D-31) requested that the rule
allow the State, as well as the Administrator, to approve
equivalent methods of control.
     Response:  The General Provisions define the
Administrator as "the Administrator, or delegated authority."
It is maintained in the final rule that the EPA retain the
authority to choose whether to delegate the authority for this
rule to the State.  The EPA has clarified in the final rule
that the Administrator will retain the authority to approve of
equivalent methods of control.  Section 112(1) of the Act
states that a program submitted by a State under this
subsection may provide for partial or complete delegation of
the Administrator's authorities and responsibilities to
implement and enforce emissions standards and prevention
requirements but shall not include authority to set standards
less stringent than those promulgated by the Administrator.
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2.5.2  Idling Standards
     Comment:  Two commenters (IV-D-34; IV-D-40) stated that
the EPA had limited data for setting emission limits.  One
commenter (IV-D-40) stated that setting a reliable idling
emission limit for an in-line cleaning machine, with no
available test data, is difficult.  One commenter (IV-D-34)
stated a concern that there is a lack of test data to support
the EPA's conclusions and that the proposed limits may be
difficult to attain.
     One commenter  (IV-D-40) stated that the idling emission
limits were determined by mathematical calculations, and do
not reflect actual reductions.  The commenter stated that the
idling emission limit for batch vapor cleaning machines should
be somewhere between the 0.4 kg/m2-hr (0.08 Ib/ft2-hr) (based
on the available test data) and 60 percent of that figure, or
0.24 kg/m2-hr (0.05 Ib/ft2-hr).  The commenter stated that
this emission limit should be verified with test data, and
recommended that this limit also be used for in-line cleaners.
     Response:  The EPA acknowledges that limited data were
available to establish this level.  The idling emission limit,
was calculated by first determining the maximum idling-mode
emission reduction that is achieved by the MACT controls.
This is 70 percent control for all solvent cleaning machines.
The uncontrolled idling-mode emission rates, 0.73 kg/m2-hr
(0.15 Ib/ft2-hr) for batch vapor cleaning machines and
0.34 kg/m2-hr (0.07 Ib/ft2-hr) for in-line cleaning machines,
were then multiplied by one minus the maximum idling-mode
emission reduction  (i.e., 0.3).  For batch vapor cleaning
machines, the idling limit is 0.22 kg/m2-hr (0.045 Ib/ft2-hr).
For in-line cleaning machines, the idling limit is
0.10 kg/m2-hr (0.02 Ib/ft2-hr).
     The sixty percent reduction referred to by commenter
IV-D-40 is the overall emission reduction, not the reduction
in idling emissions.
     Comment;  Six commenters (IV-D-20; IV-D-27; IV-D-29;
IV-D-30; IV-D-33; IV-D-35)  stated that the EPA should

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eliminate the option for an idling emission limit because it
would be difficult for a regulatory agency to implement and
even more difficult to enforce.  Several commenters (IV-D-20;
IV-D-29; IV-D-30; IV-D-33; IV-D-35) stated that more practical
procedures are available, such as limiting emissions or
applying specific control technologies, that still meet the
goals of the title III program.  Another commenter (IV-D-27)
stated that it is very difficult to document idling emissions
from solvent cleaning machines.  The commenter noted that the
total emission rate limitations are much easier to monitor on
an ongoing basis.
     Response:  The EPA has maintained the idling emission
limit in the final rule.  The EPA believes that the idling
emission limit is as practical to enforce as the equipment
standard.  Under the idling emission limit, the
facility/vendor completes a one-time idling test to establish
the equipment parameters that will be monitored and to
establish the frequency of monitoring.  One test can be used
for all vendor and/or facility cleaning machines that have the
same model design, solvent vapor/air interface, and controls.
Once the test report is approved by the Administrator, the
owner or operator conducts monitoring of the equipment
specified in the report to determine compliance.  Enforcement
is conducted by ensuring that the proper controls are
maintained, operated, and monitored.  Therefore, the
enforcement of the idling emission limit and the equipment
standard are very similar.
     The EPA does not require that an owner or operator comply
with the regulation using the idling emission limit.  An owner
or operator can choose to comply through the equipment
standards or the alternative overall solvent emission
standard.  The idling emission limit is maintained as an
option to add flexibility to the rule and to encourage
innovation and pollution prevention.
     Comment:  Two commenters  (IV-D-33; IV-D-49) stated that
the idling emission limit is impractical to measure and

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enforce.  However, one commenter (IV-D-33) supported the EPA's
objective to provide an option for existing sources to
demonstrate compliance with the minimum federal MACT
requirements with existing controls.  Both commenters
(IV-D-33; IV-D-49) suggested that one alternative approach to
the idling emissions limit would be to specify a health-based
fugitive halogenated solvent emission limit, such as a 50 ppm
limit measured 1 cm from the edge of the degreaser tank.  One
commenter (IV-D-49) stated that the fugitive emission limit
should not be exceeded at any time on an instantaneous basis.
If the limit cannot be achieved with an effective freeboard
ratio and a freeboard refrigeration device, then a lip-type
local exhaust system and carbon adsorber should be required.
The commenter added that this fugitive emission limit should
also apply to batch cold cleaning machines using halogenated
solvents.  The commenters (IV-D-33; IV-D-49) stated that this
fugitive emission limit can be easily measured by an
inspector.
     Response;  The EPA has not adopted a health-based
fugitive emission limit as an alternative in the final rule.
The EPA is required to set MACT based on the evaluation of
control levels that are achievable by a source.  The statutory
authority under section 112(d) of the Act is performance based
but allows iequipment standards under the following conditions:
(1) if the HAP cannot be emitted through a conveyance device,
or (2) if the application of measurement methodology to a
particular class of sources is not practicable due to
technological or economic limitations.  A risk based format is
not practicable due to technological and economic limitations.
Furthermore, there is insufficient data available to set
performance based fugitive HAP concentration limits for this
source.  A residual risk assessment will be performed at a
later date under the authority of section 112(f) of the Act.
     Comment:  One commenter  (IV-D-31) requested that the EPA
amend § 63.462(b)(1)(iii) of the proposed rule to allow idling
emissions of 0.5 kg/m2-hr (0.03 Ib/ft2-hr).  The commenter

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also suggested that the EPA amend § 63.462(c)(1)(ii) and
(c)(2)(ii)  of the proposed rule to allow idling emissions of
1.0 kg/m2-hr (0.2 Ib/ft2-hr) .  The cominenter stated that the
proposed idling emission limits appear to be unachievable for
both open-top and conveyorized cleaning machines.
     Response:  The commenter supplied no information or data
to support this statement.  Therefore, the EPA is unable to
reevaluate or make suggested changes to the idling emission
rate limits.  As discussed previously, an owner or operator is
not required to meet these limits.  An owner or operator can
choose to comply with this rule through the equipment standard
or overall solvent emission limit.  The idling emission limits
are maintained as an option that would allow for new/compliant
control equipment not specified in the equipment standard
control combinations.
     Comment;  Two commenters (IV-D-50; IV-D-56),  representing
the same company, stated that controlling idling emissions
will not guarantee that solvent emissions are low.  One
commenter (IV-D-50) stated that when parts are free draining
and production volume is low, solvent emissions can be
adequately controlled by reducing air movement, automating
parts movement, and proper operation.  The commenter pointed
out that when parts are not free draining and production
volumes are high, the dragout losses must be controlled.  The
commenter reasoned that the idling emission limit, which only
controls idling emissions, would not effectively control
dragout losses.  As an alternative, the cominenter suggested
that if dragout losses exceed a certain amount
(e.g. 227 kg/month [500 lb/month]) then the elimination or
minimization of dragout using a SHV system should be required.
     The other commenter  (IV-D-56) stated that as currently
written, a solvent cleaning machine meeting an idling emission
rate of 0.151 kg/m2-hr (0.031 Ibs/ft2-hr) could use an
unlimited amount of solvent.  The commenter recommended two
ways to correct this "loop-hole" in the idling emission limit:
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     (1)  Limit the working hours of the solvent cleaning
machine as part of idling emission compliance, or
     (2)  Remove the idling emission limit and rely on the
alternative standard for low end users of solvent.
     Response:  The EPA has not required SHV for all owners or
operators cleaning parts that are not free draining or with
high production volumes and has retained the flexibility of
the proposed rule.  Super-heated vapor is offered as one of
the controls in the equipment standard and could be used to
comply with the alternative standard.
     The EPA acknowledges that only idling emission losses are
controlled by the idling controls (e.g., cover, increased
freeboard ratio, freeboard refrigeration device); however, the
idling standard alternative includes work practice
requirements to limit other losses,  such as drag-out losses.
The regulation does not ignore the amount of dragout and
production.  In the equipment standard, dragout is addressed
by requiring a hoist at a regulated speed, the proper racking
of parts so that solvent drains freely, the dwell control
option, and the SHV control option.   The ban on the cleaning
of materials such as sponges, fabric, wood, and paper
addresses carryout emissions.  In the equipment standard, the
amount of production was taken into account when developing
the operating schedules that were used to calculate the
overall emission reduction efficiency of the control
combinations.  Dragout is addressed in the idling standard by
the following provisions:  (1) Requiring a hoist at a
regulated speed and work practices,  such as the requirements
for the proper racking of parts so that solvent drains
freely; (2) the requirement that all condensation and dripping
must stop before the part can be removed from the freeboard
area; and (3) the requirement that materials such as sponges,
fabric wood, and paper shall not be cleaned in the solvent
cleaning machine.
     In order to meet the alternative standard's limit, the
owner or operator would probably need to reduce carryout

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losses.  The alternative standard is based on a 2 hour working
schedule 365 days a year, and therefore addresses production
volume.
     Idling Test Method
     Comment;   One commenter (IV-D-50) stated that the 16 hour
idling emission test may not necessarily be accurate.  The
commenter stated that they have conducted hundreds of slant
inclinometer tests on dozens of different types and sizes of
solvent cleaning machines over 15 years, both in the idling
mode and during working.  The commenter found that the results
of the tests could vary widely due to the following factors:
     1.  The temperature in the immersion sump will fluctuate
with room and condensing coil temperature.
     2.  The amount or rate of boiling can change
significantly and rapidly, especially in a steam heated
solvent cleaning machine.  Fluctuations in voltage can affect
electric sump coils.  If the boiling rate is high, the
presence of more vaporized solvent in the boiling sump will
raise its apparent level.  Also, as boiling rate increases,
more vapor is present in the vapor zone.
     3.  One hundred and eighty-nine liters (50 gallons) of
TCE, if heated or cooled 10 degrees, represents a change in
volume of 1.23 liters (0.325 gallons) or 1.8 kg (4 Ibs) from
vaporization/condensation.  This change can occur in the non-
boiling sump.   This change either doubles the apparent loss,
or perhaps eliminates it entirely, depending on whether the
temperature is increased or decreased.
     4.  Condensing temperatures can vary, causing significant
variations in the amount of solvent vapor in the vapor zone.
     Any vapor volume change will alter the amount of liquid
that seems to be in the liquid sumps.  The commenter stated
that in order to use the idling emission test recommended by
the EPA, it is necessary that room temperature, rate of
heating, cooling temperature and barometric pressure remain
constant.  The commenter believes that slant inclinometer
tests are useful, but one must record room temperature, steam

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pressure, sump temperature, voltage, cooling temperatures, and
barometric pressure.
     Response;  The EPA acknowledges that the results of an
idling emission test could be affected by the operating
parameters under which the test is conducted.  The EPA does
not think it is unreasonable to require owners or operators of
tested cleaning machines to maintain measured parameters
relatively constant.  The EPA has, therefore, maintained the
use of a slant inclinometer in the idling emission test.
     Comment;  Two commenters (IV-D-31; IV-D-34) had the
following comments on the proposed test method:
     (1)  One commenter (IV-D-31) requested that the test
method clearly state that the idling emission rate is
determined with the cover(s) in place.
     (2)  One commenter (IV-D-31) requested that EPA's test
method 307 should allow use of any suitable tubing, and not
require the use of Teflon tubing because it refers to a
specific product and company.
     (3)  One commenter (IV-D-31) requested that the EPA
change section 3.4 of Method 307 in appendix A from "(check
with manufacturer)" to "(it may be helpful to check with
manufacturer)" because of the mandatory nature of the
appendix, which would require the tester to check with the
manufacturer each time the test was performed.
     (4)  One commenter (IV-D-34) stated that Method 307 could
be made more flexible by allowing the use of a sight glass or
sample profile thief, in lieu of incline level indicators, for
determining sump liquid levels.   The commenter  (IV-D-34) also
stated that the principle behind the calculation employed in
Method 307 could be summarized to aid in clarity.
     (5)  One commenter (IV-D-40) was concerned that the
proposed Test Method 307 may allow TCE and MC to reach
explosion limits and would increase worker exposure.
     Response:  The EPA has not delineated conditions for
which a cleaning machine is tested.  The conditions are to be
determined by the user.  The tested conditions, if determined

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to be compliant, are then required to be maintained.  The
final rule requires that all batch vapor cleaning machines
have a cover or equivalent in place during the idling mode.
Therefore, it would be a violation of the rule if the cover
was not in place during the idling test.  The EPA has modified
the test method to allow for the use of tubing material that
will not react with solvent and does not allow solvent vapors
to permeate the tubing material, which allows the use of
Teflon®.
     The EPA did not intend that a tester should be required
to check with a manufacturer each time the idling test was
performed.  Therefore, the phrase "check with manufacturer" in
Method 307, appendix A,  was revised to read, "it may be
helpful to check with the manufacturer."
     The EPA would allow for the use of a sight glass or
sample profile thief, in lieu of an incline level indicator if
the owner or operator demonstrates to the Administrator's
satisfaction that these measuring devices are equivalent.
     The EPA does not agree with the commenter's concern that
the proposed method may allow levels of TCE and MC to reach
explosion limits or increase worker exposure.  No data were
supplied to support this claim.  The cleaning machine is run
under normal operating conditions.  Explosion limits are no
more likely to be reached than during normal idling
conditions.  Furthermore, both MC and TCE have nonexplosive
nonflammable properties.  Worker exposure is no greater under
test conditions than under normal idling conditions.  In fact,
worker exposure during the idling test is likely to be less
than during normal working conditions.
     Comment;  Three commenters (IV-D-06; IV-D-31; IV-D-40)
requested clarification on the provisions for demonstrating
compliance with the idling standard.  Two commenters (IV-D-06;
IV-D-40) commented on the compliance requirements for the
idling standards.  One commenter  (IV-D-06) stated that
§ 63.467(c)(3) (i) of the proposed rule indicates that the test
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must be performed on the same model cleaner as the one at the
source, whereas § 63.467(c)(3)(iv)(A) of the proposed rule
states that the vendor must supply a statement that "the unit
tested is the same as that for which the report is being
submitted."  The intent of the rule should be clarified to
state whether each machine must be tested or whether it is
sufficient for the vendor to perform testing on each model.
Two commenters (IV-D-34; IV-D-40) stated that the time and
frequency of idling compliance testing was unclear.  One
commenter (IV-D-40) felt it was not clear in the preamble and
proposed regulations whether the idling emission rates
proposed can be met and how often, or in what manner,
operators would be required to demonstrate compliance.
     One commenter (IV-D-40)  recommended that the EPA simplify
the requirements for compliance with the idling emission
limit, stating that separate EPA approval of monitoring
parameters and frequency appears unnecessary.  The commenter
stated that vendors may be unwilling to provide a statement to
an operator based on vendor data that demonstrates compliance
with the idling emission limit without testing the actual
equipment, rather than a similar model.  Two commenters
(IV-D-31; IV-D-34) stated that the EPA should clarify whether
the idling mode emission test is a one-time test or whether
subsequent testing would be required.
     One commenter (IV-D-31)  suggested that the EPA allow an
idling emission test report from persons or companies other
than the vendor [e.g., private testing organization,
manufacturer (who may not be the vendor), another company that
runs the same model of machine] as an acceptable report.  The
commenter suggested that the EPA amend § 63.467(c)(3)(i) of
the proposed rule by deleting the phrase "the vendor of that
solvent cleaning machine," and simply say "others."
     Response:   The EPA's intent was to allow for the vendor
or other third party to perform testing on each of their
models.  The vendor or other third party could then supply the
test results to the owner or operator of a compliant model.

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The EPA has clarified in the final rule that the idling
emission test report can be performed by persons or companies
other than the vendor.
     The idling compliance test is a one-time test.
Compliance thereafter is determined by monitoring the control
parameters that need to be maintained to demonstrate
continuous compliance, by keeping records of this monitoring,
and by submitting the appropriate reports.  A control device
monitoring report is required beginning one year after the
compliance date.  The idling compliance test is to be kept
on-site for the lifetime of the cleaning machine.  Records of
control device monitoring are to be maintained on-site for
5 years.  The EPA reserves the right to approve monitoring
parameters and the monitoring frequency used to determine
compliance with the idling emission limit.
     A guidance document to the final halogenated solvent
cleaner NESHAP is currently being prepared to aid owners or
operators of halogenated solvent cleaning machines in
complying with the rule.  This guidance document should
further assist an owner or operator to comply with the idling
emission limit.
     Comment:  One commenter (IV-D-04) pointed out that the
units of the standard are in kilograms/square meters-month
(kg/m2-month) while the equations presented in § 63.464(b)
yield emission rates in kilograms of solvent/month (kg/month).
The commenter  (IV-D-04) suggested that the equation be
corrected in the regulation to be consistent with the units of
the standard.
     Response:  The EPA has modified the equation that
appeared as equation 1 in the proposed rule to be consistent
with the units of the limits that were listed in table 2 of
the proposed rule.  Specifically, the EPA has divided the
right side of the equation by the solvent-air interface area
of the cleaning machine (m2 [ft2]).  The EPA has also modified
the equation that appeared as equation 3 in the proposed rule
to be consistent with this change.

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     Comment:   One commenter (IV-D-04) stated that equation
307-4 yields an emission rate in grains per cubic meter per
hour (m3/hr),  while the emission limit standard is in terms of
kilograms per hour per square meter of solvent/air interface
(kg/m2-hr).  The commenter (IV-D-04) suggested that this
discrepancy be corrected.
     Response;  The EPA has modified equation 307-4 of the
proposed rule so that the units of E are in kg/m2-hr
(Ib/ft2-hr).  This makes the equation consistent with the
idling emission limits in the standard.
2.5.3  Work Practices
     Comment;   One commenter (IV-D-54) stated that, to avoid
duplication or conflicting requirements, the EPA should either
coordinate waste-related issues associated with this
rulemaking with expected RCRA decisions, or delete
§ 63.462(d)(11) of the proposed rule, which requires the waste
to be stored in closed containers.
     Response:  The requirements under RCRA are applicable
only to those facilities that are required to obtain a RCRA
permit.  Not all facilities using halogenated solvent cleaning
machines are required to obtain a RCRA permit.  Therefore, the
requirements in § 63.462(d)(11) of the proposed rule were
included to ensure that all owners or operators of solvent
cleaning machines handle their solvent wastes properly.  These
requirements are consistent with the RCRA requirements and
have not been removed from the rule.
     2.5.3.1  Operator test
     Comment:  Several commenters (IV-D-20; IV-D-29; IV-D-31;
IV-D-33; IV-D-35; IV-D-46; IV-D-54) questioned the
enforceability of and need for the operator test in
§ 63.462(d)(10) of the proposed rule.  One commenter (IV-D-46)
listed the following problems with the operator test:
     (1)  A disgruntled employee could purposely "flunk" the
test and put the company in violation and subject to fines.
     (2)  The test method is not specified (oral, written or
other).

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     (3)   If the test material is presented in a manner that
is inconsistent with the training an employee was given, then
the employee could fail the test and place the company in
violation and subject to fines.
     (4)   The consistency of application of the operator test
seems very subjective and dependant on the inspector.
     Two commenters (IV-D-31; IV-D-33) suggested deleting the
EPA's proposed operator test.  One commenter (IV-D-31)
provided the following reasons:
     (1)   The test is not identified;
     (2)   They do not train "all operators" or train them to
use "solvent cleaning machines."  They train their operators
to use the specific machine(s) they will be operating.
     (3)   An employer does not have control over each
employee's ability to answer questions on a particular test at
a particular moment.
     (4)   There will not necessarily be a link between the
elements of the test, and the work practices required by the
rule.  For example there may be no need for any specific
employee using the machine to know how to do the dwell
calculations.
     (5)   The number of employees that operate a solvent
cleaning machine could be anywhere from 10 to 100 and it could
be cost-prohibitive to train them all.  The operators of a
cleaning machine only need to know how to operate the machine
with properly functioning control devices.  Lessors,
supervisors, engineers, or maintenance workers would need to
know how to conduct the required tests to verify that the
control devices are functioning properly.
     (6)   The commenter was concerned that the EPA had not
described how it would assure that the test was "a good one."
     One commenter  (IV-D-36) stated that, since different
individuals may be familiar with different aspects of the
solvent cleaning machine operation and monitoring, the EPA
should allow the different sections of the test to be taken by
different individuals.

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     One commenter (IV-D-21) requested that § 63.462 (d) (10) of
the proposed rule be revised to reflect that the machine
operator, not necessarily the owner, must be familiar with the
required work practices for that equipment.  The commenter
also indicated that the content of the "test" supplied and
administered by an inspector is not defined.  The commenter
pointed out that the preamble stated that the "operator
qualification test" would include such information as the
"method for calculating correct work practices."  The
commenter argued that the cleaning machine operator may
understand the procedures and work practices without needing
to understand the methodology for determining such parameters.
The commenter recommended that compliance with the work
practice standard, or operator qualifications, be determined
through visual observation of the operator while performing
the work practice standards.
     One commenter (IV-D-35) recommended that the operator
test be replaced with a provision that requires copies of
operating and maintenance instructions be located at the
cleaning machine.  Another commenter (IV-D-54) recommended
replacing the operator test with a requirement for annual
training of operators.  The commenter (IV-D-54) recommended
placing the following wording in § 63.467 (e)(2) of the
proposed rule "...all operators of solvent cleaning machines
have received training on the proper operation of solvent
cleaning machines and their control devices."  The commenter
(IV-D-54) stated that the training records and documentation
could be maintained at the site and kept available for
inspection by the EPA.
     Response:  The EPA has maintained the operator
performance test.  The EPA concluded that the intentional
failure of the operator test by a solvent cleaning machine
operator would be rare and could be contested by the owner of
the solvent cleaning machine.  This test is a basic test,
which an employee given basic training in the operation of the
solvent cleaning machine should be able to pass.  The final

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operator test does not require that an operator of a solvent
cleaning machine know how to perform the dwell calculations or
other methods for calculating correct work practices.  Nothing
in this rule precludes the owner or operator from posting the
requirements or even the completed test - in the view of all
employees.  This sign would only need to be covered during the
actual testing process.
     The EPA has included the actual operator test and answers
in the final rule.  The EPA believes that the operator test is
effective because it includes questions that, if answered
correctly, demonstrate an operators knowledge of the proper
operation of their particular cleaning machine.  Proper
operation means operating the cleaning machine in such a way
as to minimize halogenated HAP emissions, as specified in the
rule.  Only those work practices essential for an operator to
know are included in the test.  It is not necessary to include
two different tests.  The final rule clarifies that the
halogenated solvent cleaning machine operator, and not
necessarily the owner, must be familiar with the required work
practices for that equipment.  The EPA does not believe that
visual observance of an operator while performing work
practice standards is sufficient to determine whether an
operator knows the required work practices.
     The EPA considered a number of options to determine
compliance with work practices.  Operator training in adjunct
to labels specifying work practices, and the potential for
on-site inspections and testing was determined to be the best
means of achieving such a determination.
     Comment;  One commenter  (IV-D-51) stated that the
operator qualification test should be administered during
in-house training classes rather than during inspections.  The
commenter stated that if the test is administered at the end
of the training class, the test results would provide valuable
feedback to the instructor on the effectiveness of the
training.  The commenter recommended that the training should
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consist of an initial training class, followed by annual
refresher training.
     Response;  The owner or operator may administer an
operator test during in-house training classes.  However, the
EPA does not require these classes and an operator would still
be required to take the test during inspections.  The EPA
considered annual testing; however, it was determined that
this testing would be too burdensome on owners or operators.
The EPA concluded that in-house training was already in-place.
The EPA believes that the best method for the EPA to determine
compliance without excessive burden to an owner or operator is
to test during inspections.
     2.5.3.2  Other work practices
     Comment:  One commenter (IV-D-27) questioned whether the
small solvent savings from the solvent transfer requirements
in § 63.462(d)(8) of the proposed rule outweighed the costs.
The commenter stated that the cost of replumbing would be a
significant investment for smaller sources.
     Response:  The proposed requirements do not require
sophisticated plumbing.  The solvent transfer requirements
only require that solvent be transferred using leakproof
tubing and that the solvent is removed or added below the
liquid surface.  This requirement is in place to avoid solvent
losses due to leakage, spills,  and splashing.
     Comment:  One commenter (IV-D-35),  in reference to the
spraying operations requirements, requested that a statement
similar to the following be added to § 63.462 (d)(3) of the
proposed rule: "the machine be devoid of any flushing wand
which produces any VOC droplets or mist or which delivers a
stream of any VOC under a line pressure in excess of 15 pounds
per square inch gauge."
     Response:  Provisions in the proposed and final rules are
sufficient to limit emissions from spraying.  The EPA has not
added the commenter's suggested language to the rule because
the commenter has not provided data that show that the
additional emission reductions that would result from these

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requirements would justify the added costs.  However, nothing
in this rule would preclude a State or regulatory agency from
adding such a requirement.
     Comment:  Two commenters (IV-D-50; IV-D-54) commented on
the requirement in the proposed rule for owners or operators
to orient parts or rotate them so that solvent drains
properly.  One commenter  (IV-D-54) stated that the requirement
in § 63.462(d) of the proposed rule to tip or rotate parts
before removal from the machine may be difficult to implement
on certain existing equipment without major modifications.
Another commenter (IV-D-50) stated that, even with proper
racking and/or rotation, some parts require the use of SHV to
reduce the carry out of solvent.
     Response;  Owners or operators that find the tipping
and/or rotating of parts to be difficult or impractical to
incorporate into their cleaning operations, may either apply
to the Administrator for alternative requirements or choose to
comply with the alternative standards.  There are several
methods of reducing carry out emissions in the rule.
Superheated vapor is one of these.
2.5.4  Overall Solvent Emission Limit Standard
     Comment;  Several commenters (IV-D-06; IV-D-12; IV-D-20;
IV-D-30; IV-D-32) voiced concern that the alternative standard
may allow some facilities to avoid emission control
completely.  They stated that a facility could install a large
number of solvent cleaning machines with no controls and limit
their individual hours of operation on each machine.  They
would then be in compliance with the standard, without
controlling emissions.  One commenter (IV-D-06) stated that
the value of uncontrolled solvent cleaning machines will
significantly decrease after promulgation of this NESHAP and
could therefore be purchased cheaply.  While this approach
would result in an increase in operating costs, it could
provide short-term savings due to the lower capital
investment.
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     Another commenter (IV-D-30) stated that the alternative
standards should be removed.  The commenter stated that the
alternative standard is too complex, requires too much effort
to show compliance, and it would allow companies to operate
poorly for shorter periods rather than controlling emissions
properly.  The commenter reasoned that while reducing the
number of options available to sources may inhibit some of
their operating flexibility, this will be outweighed by
increased clarity and better compliance with the standard.
     As an alternative, several commenters (IV-D-06; IV-D-12;
IV-D-20; IV-D-32) recommended that the overall solvent usage
be expressed as a rate (i.e., tied to hours of operation of
individual degreasing machines).  Two commenters (IV-D-20;
IV-D-32) recommended that facilities with emissions above a
certain threshold value should be unable to choose the
alternative standard.  Another commenter (IV-D-12)  stated that
the emission limit could be based on work throughput.
     Response;  The EPA does not believe that industry would
opt to use multiple cleaning machines to avoid regulation
under this NESHAP.  Such an approach would involve significant
additional costs, such as the capital cost of the additional
cleaning machines, the cost of the additional floor space,
installation and maintenance costs, and utility costs.  Even
though the total working time of all the machines may be kept
the same as before, the idling emissions and downtime
emissions will increase, causing an increase in solvent use.
This increased solvent usage could be a significant expense.
In addition, the owner or operator would experience additional
recordkeeping and reporting costs for the added cleaning
machines.  It seems unlikely that an owner or operator would
go through such trouble and expense to avoid being regulated.
In addition, if there were to be a demand for uncontrolled
cleaners as the commenter suggests, the costs of these units
would not likely "decrease significantly."  This would only
happened if an owner chose to buy a new compliant cleaning
machine in-lieu of retrofitting their existing noncompliant

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cleaning machine.  Since retrofit capital costs are less than
purchasing a new cleaning machine, this is an unlikely
scenario.
     The cost analysis, conducted by the EPA, shows that the
rule will actually result in a cost savings for many owners or
operators as a result of decreased solvent usage.  Therefore,
the alternative standard has not been changed.
     Comment:  One commenter (IV-D-60) recommended that the
EPA provide an alternative standard for batch cold cleaning
machines similar to the one that is provided for batch vapor
and in-line cleaning machines in § 63.463 of the proposed
rule.
     Response:  The EPA does not have sufficient data to
establish an alternative standard emission limit for batch
cold cleaning machines.  The EPA requested additional
information on batch cold cleaning machines in the proposed
rule.  No additional information was received that would
assist the EPA in setting an emission limit for batch cold
cleaning machines.
     Comment:  Seven commenters (IV-D-26; IV-D-27; IV-D-31;
IV-D-34; IV-D-40; IV-D-50; IV-D-56) felt that the alternative
standard emission limits were unreasonable.  Four commenters
(IV-D-26; IV-D-34; IV-D-40; IV-D-50) stated that solvent
emissions are underestimated and larger machines are penalized
by assuming that they are operated under the same schedule as
smaller machines.  Two commenters  (IV-D-31; IV-D-40)
recommended that the EPA establish per-shift emission limits
for cleaners operating more than one shift.
     One commenter (IV-D-50) stated that the emissions allowed
by the alternative standard are no more than those from a
cleaning machine that was idling for one month, thereby
ignoring the volume of production and the number of shifts per
day that the cleaning machine operates.  Out of 20 cleaning
machines they have built and that used the following controls:
high freeboard, enclosure, automatic handling, parts rotation,
a proper condensing system and/or freeboard cooling, no lip

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exhaust, and SHV, only 4 could meet the 3-month rolling
average limits.  The commenter stated that if the 3-month
rolling average limit was increased by 50 percent then nine of
the cleaning machines would comply, if the limit was increased
by 100 percent then 16 would comply.  The commenter
recommended that the 3-month rolling average emission limit be
increased by 100 percent.  The commenter offered to provide
the EPA data on the size and emissions of the 20 solvent
cleaning machines they studied, plus many more machines.
     Another commenter (IV-D-56) from the same company stated
that if the EPA doubled the alternative standard emission
limit, 75 percent of the machines their company manufactures
would comply.  For example a 4.8 m2 (52 ft2) cleaning machine
with a 1.0 freeboard ratio, enclosure, SHV, dwell,
refrigeration device, automated hoist, and automatic rotation
does not meet the proposed alternative standard.  The cleaning
machine emits solvent at a rate of 0.29 kg/m2-hr
(0.06 Ib/ft2-hr), which is double the proposed 3-month rolling
average.  The machine processes 1,864 kg (4,100 Ibs) of parts
per hour averaging 8 loads/hr and is run 16 hours per day.
The commenter's concern was that the owners or operators of
these machines would be needlessly subjected to excessive
monitoring and testing requirements.
     One commenter (IV-D-53) stated that their client's small
(29" by 35" [0.74 m by 0.89 m]) open-top solvent cleaning
machine does not meet the emission limit, despite having been
recently permitted by the New Jersey Department of
Environmental Protection and Energy (NJDEPE) for emissions of
MC at a rate of 0.91 kg/hr (2 Ib/hr).  The cleaning machine
operates 44-hours a week and emits as much as 2.34 kg/m2-month
(55.3 lb/ft2-month), which exceeds the EPA proposed limit of
0.95 kg/m2-month (22.49 Ib/ft2-month).  The unit has a
freeboard ratio of 0.75, cool-down coils, and a hoist with
parts rotation.
     Another commenter (IV-D-27) stated that several small
degreasers which currently comply with their regulations on a

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kg/m2 basis had emissions in excess of the alternative
standard.  The conunenter stated that some of the cleaners that
exceeded the alternative standard were considerably smaller
than 0.93 m2 (10 ft2), operated only one shift per day, five
days per week, and used less than a ton of solvent per year.
     One conunenter (IV-D-34) stated that the alternative
overall emission limits would:
     (I)  Effectively prohibit many operations utilizing large
machines from considering this option.
     (2)  Penalize those operations that maximize the use of
their existing equipment.
     (3)  Create an unnecessary barrier to increased
production and business growth for those complying with this
option.
     Several commenters (IV-D-31; IV-D-34; IV-D-40)
recommended that the EPA establish total emission limits that
are based on the typical operating schedules and emissions of
both batch and in-line cleaners,  one commenter (IV-D-40)
provided some recommended limits that provide a level of
control comparable to that proposed by the EPA for MACT for
all vapor cleaner subcategories.  The commenter stated that
they view the conservative assumptions used to calculate the
proposed total emission limits as an unnecessary safeguard
against deliberate under-utilization of equipment capacity,
particularly for in-line equipment.  The higher costs of large
and very large batch vapor cleaners makes it unlikely that
this equipment would be under-used unless warranted by the
workload.  Another commenter  (IV-D-31) estimated that a hourly
emission limit for working emissions should be two to four
times the idling emission rate, or approximately 1.5 kg/m2
(0.31 lb/ft2 per working hour) for in-line cleaners.
     Response:  As stated in the preamble, it is expected that
this alternate standard will be more difficult to meet for
larger machines and machines operating for more than one shift
or that clean parts with difficult configurations.  It was not

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possible to account for these variables when establishing
alternative emission limits without making the alternative
standard unenforceable or overburdensome.
     When establishing the limits for the alternative
standard, the EPA considered, but rejected, establishing a
limit based on the number of hours or shifts operated.  The
EPA concluded that providing a limit based on the number of
hours or shifts operated was unreasonable for several reasons.
Since no capital cost would be involved, a limit per shift
would encourage a facility to keep a machine "on" for longer
periods, while cleaning no additional parts.  A limit per hour
or shift would also require that the owner or operator conduct
additional reporting and recordkeeping to establish the
operating schedule.
     If a cleaning machine can not meet the alternative
standard as operated, the owner or operator could install
additional controls or employ better work practices to meet
the alternative standard.  Other compliance options, such as
the equipment standard and idling emission standard are also
available for situations where a cleaning machine cannot meet
the alternative standard.
     The overall solvent emission limit for batch vapor
cleaning machines has been increased in the final rule.  This
is the result of removing the redundancy in control
combinations.  The final batch vapor solvent cleaning machine
overall solvent emission limit is 150 kg/m^-month.
     Comment;  Three commenters (IV-D-38; IV-D-41; IV-D-47)
commented on the achievability of the standard.  One commenter
(IV-D-38) stated that the numerical emission limits are too
stringent, unproven, and become effective too soon.  However,
no data were provided to support these statements.  Another
commenter (IV-D-47) stated that the emissions limits in the
proposed regulations are not reasonable and would cripple or
destroy their business.  The company uses TCA and, despite
controls on the cleaning machines, they still lose as much as
two gallons per day per machine.  The commenter asked that the

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EPA reconsider the regulation until such time that suitable
alternatives are available.
     The other conunenter (IV-D-41) was concerned about the
alternative standards proposed in § 63.463 of the proposed
rule, but was unable to comment at this time as to whether the
emissions levels allowed in the NESHAP will meet SCAQMD's Rule
1401 for new or modified permit units.  The commenter
requested additional time and copies of the data that were
used for the derivation of the emission limits so that they
could conduct their own risk assessments to determine
equivalency with SCAQMD's Rule 1401.
     Response;  If the owner or operator cannot meet the
alternative standard, the owner or operator can choose to
comply with either the equipment standard or the idling
emission limit.  The EPA has extended the compliance time from
2 years to 3 years to allow owners or operators additional
time to determine the most efficient method for complying with
the rule.
     As requested, the EPA has sent commenter IV-D-41 the data
that were used in the derivation of the emission limits.  It
should be noted that this background information is available
to the public in the docket (Docket No. A-92-39).  The comment
period for the rule was not extended.
     Comment:  Five commenters (IV-D-06; IV-D-20; IV-D-29;
IV-D-40; IV-D-46) discussed the equation presented in
§ 63.464(b)(3) of the proposed rule.  Three commenters
(IV-D-06; IV-D-20; IV-D-46) questioned the validity of the
emission factor that is used in equation 2 in § 63.464(b)(3)
of the proposed rule.  One commenter  (IV-D-06) stated that the
emission factor is excessive because it provides a credit
against emissions ranging from over one-third to nearly half
of all solvent used in an effort to account for the solvent
disposed as solid waste.  The commenter stated that the
emission factor is unnecessary because halogenated solvent
wastes from solvent cleaning machine operations are regulated
as hazardous wastes under RCRA and therefore must be

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manifested and accounted for.  Waste disposal records required
under RCRA should be utilized in the NESHAP material balance.
The weight of waste is a known quantity and should not be
estimated as a fraction of solvent used.  The solvent percent,
by weight, of the waste should be based either on waste
profiles required under RCRA or on a conservative emission
factor.
     One commenter (IV-D-46) stated that the use of one
emission factor for all solvents is questionable because of
the wide variety of solvents and cleaning requirements.
     Two commenters (IV-D-29; IV-D-40) felt the approach for
determining solvent loss was overly complicated.  One
commenter (IV-D-29) recommended that the test methods should
include the following paragraph, if the EPA continues to keep
emission limits in the rule:
     11 (a)  Each owner or operator of a batch vapor or
     in-line solvent machine choosing to comply with the
     requirements of the regulation through the emission
     limits shall demonstrate compliance with the
     applicable 3-month rolling average monthly emission
     limit on a monthly basis.  Total solvent emissions
     can be calculated by material balance."
     This paragraph would allow an owner or operator to
develop their own approach for developing a material balance.
Another commenter  (IV-D-40) suggested that the formulas in
this section should be simplified to make them more
understandable.
     Response;  The EPA reviewed RCRA forms 8700-22 and
8700-22A and determined that the information required on these
may not be detailed enough to determine the amount of solvent
waste that is removed from a particular solvent cleaning
machine.  The forms request the quantity of the waste, but not
the composition of the waste.  For example, a barrel of waste
solvent may contain a significant amount of the contaminants
that were removed from the parts being cleaned.  The forms do
not request a breakdown of the content of the waste to that
level of detail.  In addition, the RCRA forms do not require
that the specific sources of the solvent be listed separately.

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The information must be for a specific cleaning machine if
emissions are to be calculated for each cleaning machine.
     However, the EPA acknowledges that an emission factor may
not accurately estimate the amount of solvent that is
contained in the solid waste for all types of cleaning
operations.  In addition, the EPA wants to provide each owner
or operator the flexibility to choose the estimation method
that is the most effective for their operations.  Therefore,
the EPA has removed the emission factor equation from the
final rule, and has added provisions to the rule that allow
the owner or operator to calculate the amount of solvent in
the solid waste using Method 25d or engineering calculations.
     Comment:  Four commenters (IV-D-10; IV-D-26; IV-D-31;
IV-D-40) stated that older machines may have difficulty
achieving the solvent emission limit.  The commenters stated
that the proposed alternative standard emissions limit assumes
that the same level of control can be achieved by installing
control equipment on existing, older machines as can be
achieved by applying control technology to new machines.  The
EPA should take the differences between new and existing
equipment into account in formulating any alternative
emissions limit, as well as in specifying control equipment
options that are applicable to all machines.  One commenter
(IV-D-10) recommended a variable rate that would allow larger
and older machines to use the alternative standard.
     Response;  As stated in the response to a previous
comment, the EPA does not expect that every cleaning machine
will be able to meet the alternative standard emission limit.
This standard was established based on a limited operating
schedule.  The rule offers owners or operators of cleaning
machines the additional flexibility to comply using the
equipment standard or the idling emission limit.  The EPA
believes that a variable rate, allowing larger and older
machines to use the alternative standard, would encourage
owners or operators of these cleaning machines to continue to
use otherwise noncompliant cleaning machines.

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     The alternative standard emission limits for in-line
cleaning machines have not been changed.  However,  as
discussed previously, the overall solvent emission limit for
batch vapor cleaning machines has been increased in the final
rule.  The final overall solvent emission limit for batch
vapor cleaning machines is 150 kg/m2 month.
     Comment;   One commenter (IV-D-33) agreed that use of an
emission limit provides an incentive for innovative emissions
control strategies that limit solvent use.  However, the
commenter argued that the EPA should allow States to implement
individual emission limits for each solvent.  The commenter
stated that the single monthly average does not reflect the
relative toxicity of the variety of halogenated solvents being
regulated.
     Response;  There is nothing in the NESHAP that would
preclude a State from setting a more stringent standard for
each halogenated HAP solvent being regulated.  The NESHAP is
based on the maximum degree of emission control for all the
halogenated HAP solvents being regulated and does not reflect
relative toxicity.
     Comment;   Six commenters (IV-D~27; IV-D-31; IV-D-40;
IV-D-46; IV-D-47; IV-D-54) commented on the requirement to
have only clean solvent in the machine before determining
solvent consumption (§ 63.464(b)(l) of the proposed rule).
Two commenters (IV-D-40; IV-D-46) stated that the requirement
to empty and clean the cleaner every month seems to conflict
with the EPA's waste minimization objectives.  Two commenters
(IV-D-06; IV-D-20) did not see the purpose for this
requirement and recommended deleting the requirement.
     One commenter (IV-D-31) stated that the EPA should not
require unnecessary cleaning of solvent, and should add
flexibility to the timing of determining that solvent is
clean, and to the methods that may be used to clean solvent.
The commenter suggested that the EPA require verification of
"clean" solvent monthly, where if the solvent is still within
acceptable specifications for use, it would not require

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cleaning and that the cleaning methods not be limited to
filtering, skimming, and/or distillation.  The commenter
suggested that the definition of "clean liquid solvent" be
revised as follows:
     "Clean liquid solvent means fresh unused solvent or
     used solvent that has been cleaned of soils
     (e.g., skimmed of oils or sludge, strained of metal
     chips.)"
     Another commenter (IV-D-37) stated that the period for
calculating the average emissions under the alternative
standard should be extended to avoid the necessity for
premature solvent replacement.
     One commenter  (IV-D-37) stated that the solvent in large
vapor degreasing machines at some airline maintenance
facilities is replaced every three to five months, and that
the proposed standard would require replacement of the solvent
on a monthly basis, incurring an additional cost to the
operator/owner.  The commenter also stated that, with more
frequent changes, total emissions would increase as a
consequence of repeated draining, transportation, and disposal
of only partially spent solvent.
     One commenter  (IV-D-46) stated that the cleaning machines
at their facilities are emptied only when the solvent is "too
dirty" to clean parts to specification.  The commenter
(IV-D-46) also stated that the more frequent solvent transfers
required in this section of the rule will create additional
labor and solvent costs.
     One commenter  (IV-D-54) stated that in § 63.464(b)(l) of
the proposed rule the EPA should clarify that "clean solvent"
means solvent that still retains adequate capacity to clean
materials, rather than requiring replacement with fresh
solvent.  Another commenter (IV-D-27) stated that
equation  (1) in § 63.464(b)(2) of the proposed rule is
confusing because "clean liquid solvent" would not generally
be removed from the solvent, cleaning machine.
     Response:  The EPA did not intend for "clean liquid
solvent" to mean fresh unused solvent, and thereby require

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solvent replacement.  It was EPA's intention for "clean liquid
solvent" to mean solvent that is free of soils as was
specified in the proposed definition of "clean liquid
solvent."  This requirement is included so that the amount of
solvent remaining in the tank is not overestimated due to
accumulated soils.  To avoid confusion, the distinction
between "fresh unused solvent" and "clean liquid solvent" has
been clarified in the final rule.
     Methods of removing soils from the solvent include, but
are not limited to, skimming, straining, and filtering.  The
definition of "clean liquid solvent" has been expanded, as
recommended by commenter IV-D-31, to allow for the use of
other methods for cleaning the solvent.
     Some cleaning machines have screens in the sump bottoms
that collect the soils.  To clean the solvent with this type
of system, the owner or operator would simply need to remove
the soils on the screen.
     Comment;  Two commenters (IV-D-27; IV-D-54) stated that
if separate emission factors are to be specified in equation 2
in § 63.464(b)(3)(1) of the proposed rule for small, medium,
large and very large cleaning machines, the size cutoffs for
those classifications should be defined at this point in the
standard.
     Response:  The EPA has removed the terms small, medium,
large, and very large cleaning machines from the final
regulation.  As discussed previously, the emission factors
have been removed from the final rule.
     Comment;  Four commenters (IV-D-04; IV-D-21; IV-D-31;
IV-D-54) discussed the timing of the monthly solvent emission
calculation.  Two commenters (IV-D-04; IV-D-54) recommended
that in § 63.464(b) of the proposed rule the phrase "the first
day of every month" be changed to "the first normal working
day of every month."  Two commenters (IV-D-21; IV-D-31)
requested that the EPA change the timing requirement proposed
in § 63.464(b) and  (b)(1) from "on the first day of every
month," to merely a monthly requirement.

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     Response;  The phrase, "the first day of every month", in
§ 63.464(b) of the proposed rule, has been changed to, "the
first operating day of every month."
     Comment;   One commenter (IV-D-28) suggested that since
the NESHAP would regulate the emissions of halogenated
solvents that are HAP's (per preamble page 58 FR 62566 and
section 112 of the CAA) , the standards in § 63.462(b)(1)(ii),
(b)(2)(ii), (c)(l)(ii) and (c)(2)(ii) of the proposed rule
should address the emissions of halogenated HAP's rather than
non-HAP's.  The commenter recommended that a HAP concentration
factor be incorporated to correct the calculations required by
§ 63.463 of the proposed rule and the emissions calculation in
Method 307 to account for actual HAP concentrations in
halogenated solvent mixtures containing both HAP's and
non-HAP's.
     Response;  The applicability section of the rule has been
clarified by stating th^at only halogenated HAP solvents are
regulated by the rule.  The equations in the rule have also
been clarified by indicating that only the halogenated HAP
components of solvent blends should be included in the
calculations.
     Comment;   One commenter (IV-D-21) stated that the
quantity of solvent purchased in a given month will not
necessarily reflect the solvent usage for a given cleaning
machine.  One commenter stated that they use a bulk solvent
storage system for filling cleaning machines and that the pipe
distribution system to the cleaning machines does not meter
the amount of solvent added to each individual solvent
cleaning machine.  Both commenters (IV-D-21; IV-D-36) stated
that a specific procedure for measuring solvent additions
would need to be developed at most facilities in order to
accurately calculate solvent emissions.  One commenter
 (IV-D-21) stated that the development of such a procedure
would result in greater compliance costs and additional
recordkeeping methods than projected by the EPA.  The
commenter requested that the EPA revise the monthly

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requirement to allow for quarterly facility-wide solvent
consumption recordkeeping and reporting for those operations
regulated under the final rule.
     Response:  The EPA does not consider the procedure for
measuring solvent additions to be too burdensome to maintain
as a monthly requirement.  Monthly measurement is required for
owners and operators complying with the overall solvent
emission limit to monitor compliance.
     The EPA has built flexibility into the regulation by
including the equipment standard and the idling emission
limits.  Therefore, an owner or operator need not choose the
alternative standards.
2.6  MODIFICATION AND RECONSTRUCTION CONSIDERATIONS
     Comment:   Two commenters (IV-D-33; IV-D-39) stated that
112(g) does not apply to area sources of HAP's, regardless of
whether these sources are regulated under a § 112(d) MACT
standard.  One commenter (IV-D-39) stated that the preamble
inaccurately stated that provisions for modifications and
reconstructions are being developed under separate rule
makings, and will be applicable to all halogenated HAP sources
subject to the proposed regulations.  The commenter suggested
that the EPA develop definitions for "construction" or
"reconstruction" under these regulated area sources for the
final solvent cleaning MACT rule, and that any machine that
has not been constructed or reconstructed must only comply
with the existing source MACT as set forth in the standard.
     Response;  The EPA concurs that 112(g) does not apply to
area HAP sources regardless of whether they are regulated
under a 112(d) MACT standard and acknowledges that the
proposal statement that states that provisions for
modifications and reconstructions are applicable to all
halogenated HAP sources was inaccurate.  The NESHAP General
Provisions were promulgated March 16, 1994.  Section 63.5 of
these provisions contain definitions and provisions for
construction and reconstruction.
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     Comment:   One commenter (IV-D-54) recommended that "new
sources" be defined as those for which construction or
reconstruction has commenced at least six months after
promulgation of the final rule.  This would be consistent with
the EPA's grace period for new refrigerant recovery and
recycle equipment under 40 CFR part 82, subpart F.  A second
alternative recommended by the same commenter was to create a
special provision for solvent cleaning machines constructed
between November 29, 1993 and the promulgation date.  These
two alternatives would avoid the danger of noncompliance with
the final rule if it is more stringent than or significantly
different from the proposed rule.
     Response;  The EPA has not changed the proposed
definition of new source in the final rule.  Under
section 112, the Act specifically defines a new source.  The
proposed NESHAP definition for a new source is consistent with
the Act's definition. There was insufficient reason to modify
the proposed new source definition in the final rule.  The
rule has not been made more stringent since proposal.
2.7  MONITORING REQUIREMENTS
     Comment;  Many commenters (IV-D-21; IV-D-25; IV-D-32;
IV-D-34; IV-D-35; IV-D-36; IV-D-40; IV-D-46; IV-D-51; IV-D-52)
provided comments on the frequency of the procedures for the
monitoring requirements.  Seven commenters  (IV-D-21; IV-D-25;
IV-D-32; IV-D-34; IV-D-35; IV-D-36; IV-D-46) stated that the
frequency of control device monitoring should be reduced.
However, one commenter  (IV-D-40) felt that the frequency was
reasonable.  The commenter stated that weekly visual
inspection of biparting and manual covers would not impose a
significant burden.
     Eight commenters  (IV-D-21; IV-D-25; IV-D-32; IV-D-34;
IV-D-35; IV-D-36; IV-D-46; IV-D-52) expressed concern that the
weekly monitoring requirements are excessive.  One commenter
(IV-D-25) suggested that other methods, such as shutting the
sump heat off when the vapor level becomes too high or when
the refrigerant becomes too warm would serve the same purpose

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and would probably be more effective than the weekly
monitoring of the air blanket and windspeed.  Another
commenter (IV-D-35) suggested that an educational program,
illustrating the cost benefit of reducing solvent usage,
coupled with limits on solvent usage, would provide greater
emission reductions than weekly monitoring.
     Two commenters (IV-D-21; IV-D-34) stated that the weekly
monitoring requirements should be eliminated in lieu of
monthly monitoring.  Another commenter (IV-D-36) stated that
the weekly monitoring for both the temperature of the air
blanket and wind speed should be reduced to quarterly
monitoring.   The commenter added that if a solvent cleaning
machine is moved, monitoring should be done at the new
location to determine if the wind speed requirements are being
met.
     In lieu of weekly RRD monitoring, one commenter (IV-D-32)
suggested that the EPA consider requiring an initial technical
report outlining the procedure used to achieve the RRD
parameters and annual testing and confirmation of the
standard.
     One commenter (IV-D-36) stated that monthly monitoring
and recordkeeping for a cover is probably unnecessary since an
operator will be constantly viewing the covers on his machine.
The commenter also stated that a monthly or quarterly
compliance test is unnecessary for dwell time on specific
parts after the proper dwell time for a part is determined.
Instead, monitoring of this requirement should be performed by
the inspection test of each operator, which can be checked by
quizzing an operator on the appropriate dwell times for the
parts with which he or she works.
     One commenter (IV-D-36) stated that monthly monitoring of
hoist speed is probably too frequent, and suggested that
rather than perform a test on the hoist, proper hoist speed
should be part of the operator's work practices test.  The
commenter qualified that if the hoist has a fixed speed,
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quarterly inspections of proper operation of the hoist would
be sufficient to ensure continuing compliance.
     Another commenter (IV-D-51) stated that the different
temperature measurements required for the various emission
control devices could be eliminated.  The commenter stated
that these parameters can be better controlled by installing
thermocouples to measure the temperatures and interlocking
them with the solvent cleaning machine's sump heating coil.
The system would prevent the cleaner from operating if
temperatures are not within required ranges.  This would
eliminate the expense of collecting and maintaining records
and would offer greater environmental protection.
     Response:  Under section 114(a)(3) of the Act, enhanced
monitoring and compliance certifications specifying whether
compliance was intermittent or continuous is required.
     The EPA reassessed the frequency of the monitoring
requirements prior to promulgation.  As a result of public
comments and further review of the provisions, the frequency
of monitoring was reduced for the RRD and hoist.
     The final rule as with the proposed rule, requires
monthly visual inspections of the covers.  In the final rule,
the temperature of the air blanket for freeboard refrigeration
devices must still be measured weekly.  If reducing the room
draft by controlling room parameters, the windspeed
measurements may be measured quarterly with weekly monitoring
of the room parameters.  If an enclosure is used to achieve
RRD, the windspeed within the enclosure must be measured on a
monthly basis.  Any change in the parameters used to maintain
windspeed would be an exceedance that must be reported to the
Administrator if not corrected within 15 days.  If a solvent
cleaning machine is moved, monitoring should be done at the
new location to determine whether wind speed requirements are
being met at the new location.
     The frequency of the monitoring for determining the hoist
speed has also been reduced in the final rule.  In the final
rule, the measurements must be made on a monthly basis for the

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first year, thereafter monitoring may be reduced if no
exceedances have occurred.  If the owner or operator can
demonstrate to the Administrator that the hoist speed cannot
exceed the required speed, then monitoring can be done
quarterly without having to wait for one year of compliance.
Again, if there is an exceedance, monitoring must be done
monthly.
     The EPA does not agree that the temperature measurements
that are required in the rule are excessive or difficult to
conduct.  A thermocouple to measure the temperatures could be
used to comply with the temperature measurement requirements
as long as these temperatures are recorded and maintained.
However, this would require a recorder that could make this
measurement method costly.
     The rule also allows an owner or operator to use an
alternative monitoring procedure for control parameters if
approved by the Administrator.
     Comment;  One commenter (IV-D-08) asked that the EPA
withdraw the statement from section VI.H. of the preamble
regarding aspects of the enhanced monitoring regulations under
title VII since they are currently being discussed in another
rulemaking, or modify this section according to the final
enhanced monitoring rule under title VII (if available).
     Response;  The EPA refers interested parties to the
enhanced monitoring rule notice for an updated discussion of
this rule.
     Comment:  One commenter (IV-D-31) requested that when the
EPA publishes the final rule, the EPA propose clear criteria
limiting the Administrator's discretion to determine
monitoring frequencies and allow a period of public comment on
these criteria.
     Response;  The EPA is responsible for approving
monitoring parameters and procedures that are contained in the
sources' initial statement of compliance.  In determining
whether the parameters and procedures are acceptable, the EPA
will consider the monitoring frequency specific to each

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source.  The EPA will only approve parameters and procedures
that are at least as stringent as those required by the final
rule.  Therefore, the EPA does not plan on specifying criteria
limiting the Administrator's discretion or provide for public
comment on this matter, as requested by the commenter.
     Comment;   One coromenter (IV-D-35) recommended that the
EPA provide owners or operators with an approved list of
alternative monitoring procedures.  The commenter stated that
this would reduce the need for the EPA to approve thousands of
alternative monitoring plans submitted by owners or operators.
The commenter stated that this would be helpful since the
proposed rule requires the owner or operator to identify
parameters within 30 days.  The commenter suggested that the
rule include a date by which sources must submit a monitoring
plan to the EPA or designated agency for approval.  The date
after promulgation should be such that small sources have
adequate time to comply.
     One commenter (IV-D-31) requested that § 63.465(c) and
(d) of the proposed rule allow alternative monitoring if the
alternative procedures are approved by "the Administrator or
the State," rather than "by the Administrator."
     Response:  The EPA provided provisions in the proposed
and final rule that allow an owner or operator to use
alternative monitoring procedures that meet the approval of
the Administrator.  The purpose of these provisions  is to
allow the owner or operator monitoring flexibility.  It would
be extremely burdensome for the EPA to compile a comprehensive
list of approved alternative monitoring procedures,  as
suggested by the commenter.  In fact, the EPA does not have
adequate information to ensure that all possibilities would be
included.  Therefore, the EPA has decided not to provide such
a  list to owners or operators of solvent cleaning machines.
However, monitoring requirements in the p   ->osed and final
rule were determined for individual controxs and not for
control combinations.  If an owner or operator of a  cleaning
machine uses one or more of the controls contained in the

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final rule in another combination, the specified monitoring
requirements for that control would be the default monitoring
requirement.  The alternative monitoring procedures must be at
least as stringent as those contained in the final rule.
     The timeframe for submitting the initial statement of
compliance has been extended from 30 days, as stated in the
proposed rule, to 150 days in the final rule.  This change was
made because, upon evaluation, the EPA concluded that
additional time was needed to compile and prepare this report.
     The NESHAP General Provisions define the term
"Administrator" to mean the Administrator or his or her
delegated authority.  Therefore, when the final rule refers to
the Administrator, this term implies the State, if the State
has been designated as the delegated authority by the EPA.
     Comment:  One commenter  (IV-D-31) suggested that the EPA
amend the specifications for measuring the temperature of
super-heated vapor systems.  The following were suggested as
possible alternatives:
     (a)  The measurement of temperature should be taken at
the point of super-heated vapors generation.
     (b)  The measurement of temperature should be taken where
the parts will be located during cleaning.
     (c)  The EPA should allow a temperature "at least"
50 percent above the solvent's boiling point, rather than
"precisely" 50 percent over the boiling point.
     Response:  The EPA has clarified that the measurement of
the SHV temperature should be taken "at the center of the
superheated vapor zone" in lieu of "at the center of the
solvent-vapor zone," as proposed.  This was chosen by the EPA
over "at the point of super-heated vapors generation" to
provide a more specific test because of the vagueness of the
location of the "point of super-heated vapors generation."
The center of the superheated vapor zone was considered the
most practicable location because it is where SHV achieves
emission control.
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     After reviewing the comments summarized above, the EPA
contacted a vendor of SHV technology to obtain additional
information on the proper operation of SHV systems.  Based on
the information received, the requirements for superheated
vapor have been changed in the final rule to "at least 10
degrees Fahrenheit (5.5 degrees Celsius) above the solvent's
boiling point."
     Comment:   One commenter (IV-D-31) stated that an
exceedance of a monitored parameter should not be deemed a
violation and requested that the EPA delete all references
that indicate that exceedances are automatically violations.
The commenter reasoned that some of the parameters and
limitations that the EPA has set are not sufficiently
achievable, and some are not supported by sufficient data.
Further, the commenter stated that the EPA needs to clarify
what qualifies as a violation.
     Response;  The EPA has clarified in the final rule which
requirements,  if not met, constitute an immediate exceedance
and which requirements, if not met, allow 15 working days to
correct the problem before it becomes an exceedance.  An
exceedance, in itself, is not necessarily a violation.  The
Administrator or delegated regulatory authority determines
whether the owner or operator has committed a violation of the
rule.
     Comment;  One commenter (IV-D-12) requested that the
exact location of the temperature measurement be specified in
the monitoring requirements for a FRD and SHV.
     Response;  As discussed previously, the EPA has amended
the final rule to indicate that the compliance temperature
measurement for SHV is to be taken at the center of the
superheated vapor zone.
     The EPA believes that the location of the FRD temperature
measurement is clearly defined in the proposed rule.
Therefore, the description of the FRD temperature measurement
has not been changed in the final rule.
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     Comment:   One commenter (IV-D-54) asked for more details
on the information the EPA would require from owners/operators
of solvent cleaners to demonstrate that the dwell time
requirements are being met.
     Response:  In the proposed and final regulation, the EPA
required that the owner or operator of a solvent cleaning
machine demonstrate compliance with the dwell control
technique by maintaining records of tests for determining
appropriate dwell times for each part or parts basket
typically cleaned.
     An owner or operator of a solvent cleaning machine using
a programmable hoist to achieve the proper dwell time could
demonstrate compliance with the dwell requirement by
submitting to the Administrator a record of the hoist program
for each part/parts basket.  Owners or operators complying
with the dwell could also demonstrate compliance with the
dwell requirement by submitting to the Administrator a table
showing each part/parts basket and its appropriate dwell time.
     Alternatively, the owner or operator may determine the
maximum dwell time using the most complex parts type or parts
basket, and then use this dwell time for all parts and/or
parts baskets.
2.8  RECORDKEEPING AND REPORTING REQUIREMENTS
2.8.1  General
     Comment;   Eight commenters (IV-D-02; IV-D-20; IV-D-22;
IV-D-29; IV-D-33; IV-D-42; IV-D-49; IV-D-52) were concerned
about the complexity and costs of the reporting and
recordkeeping requirements in § 63.467 and § 63.466 of the
proposed rule.  One commenter (IV-D-02) stated that a large
number of the affected small facilities will not be aware of
their obligations under this rule.  Three commenters (IV-D-02;
IV-D-20; IV-D-29) suggested that the EPA develop an explicit
implementation plan and "user-friendly" reporting and
monitoring forms prior to promulgation.  One commenter
(IV-D-02) also suggested that a database be created of the
known affected facilities (including their addresses) and that

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they should be notified of their obligations by mail.  One
commenter (IV-D-52) requested that the EPA look at less costly
reporting requirement alternatives.  Another commenter
(IV-D-42) requested that the recordkeeping and reporting
requirements be simplified if there are effective permitting
and enforcement programs in place at the State or local level.
     Response:  The EPA agrees that it may take longer for
smaller facilities to become aware of the final NESHAP;
however, it would be overly burdensome for the EPA to create a
database of the known facilities (including their addresses),
and/or to notify them of their obligations by mail.  However,
the EPA is preparing a guidance document to assist owners and
operators in complying with the rule.  This guidance will
include compliance tables and example reporting forms.  A
pamphlet describing the rule will also be produced.
     In order to streamline the reporting requirements and add
additional time for the sources to familiarize themselves with
the final rule, the EPA has extended the initial notification
report deadline from 90 days to 270 days.  The EPA believes
that this extension allows sufficient time for facilities to
learn about this rule.  Owners and operators of solvent
cleaning machines subject to this rule could become informed
of this rule through vendors, industry trade associations,
State regulatory agencies, and the OAQPS Technology Transfer
Network  (TTN) electronic bulletin board system.
     The EPA has also extended the submittal date for the
compliance report from 30 to 150 days, and the compliance
period from 2 to 3 years in the final rule.  The EPA concluded
that an additional year to comply with the rule was necessary
to allow owners or operators of halogenated solvent cleaning
machines time to learn about the rule, evaluate their
compliance options, and come into compliance with the rule.
The EPA also concluded that 30 days would not allow sufficient
time for some owners or operators of halogenated solvent
cleaning machines to compile and prepare a compliance report.
For example, owners or operators choosing to comply with the

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3 month rolling average solvent consumption limit.  The EPA
extended this to 150 days to allow an owner or operator
sufficient time to compile and prepare this report, regardless
of their compliance choice or company size.
     The reporting burden for owners or operators of cleaning
machines choosing to comply with the equipment standard has
also been reduced by eliminating the requirement for an annual
control device monitoring report.  The EPA determined that
reporting parameter fluctuations in lieu of submitting all of
the monitored data recorded for the year would be sufficient
to demonstrate compliance.  Therefore, the EPA decided that
records of control device monitoring could remain on site,
where, upon an inspector's request, they can be inspected.
     Comment;  One commenter (IV-D-36) stated that the rule
should specifically allow an owner or operator to modify the
means of compliance by notifying the appropriate authority in
writing of the intended change and the date when the change
would occur.  The commenter recommended that the rule specify
that no permit modification is required, but that a notice
that the means of compliance is being changed is sufficient.
     Response;  Owners or operators of solvent cleaning
machines may modify their means of compliance provided they
follow the requirements of the General Provisions.  The
proposed rule cross referenced the General Provisions, which
specifically states that any change in information already
provided to the Administrator, under § 63.9, Notification
Requirements, must be provided to the Administrator within
15 days after the change.  The final rule contains a table in
appendix C that details the applicability of the General
Provisions  (subpart A) to the rule.
     The title V permit regulation, section 70.7(e), specifies
determination criteria and requirements for both "minor" and
"significant" permit modifications.  An application requesting
the use of minor permit modification procedures allows for
streamlined procedures and processing.  A change in compliance
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method would be considered a major permit change and would
require a new permit.
     Comment:  One commenter  (IV-D-31) requested that the EPA
remove the requirements in §  63.466(b) and (c) of the proposed
rule that require routine compliance records  (e.g., results of
control equipment monitoring) be kept.
     Response;  The NESHAP General provisions [§ 63.10(b)] and
title V provisions [§ 70.6(a)(3)(ii)(B)] both require that
monitoring data and support information that verifies
compliance with the rule be maintained for 5 years.  The
proposed requirements are consistent with these provisions and
are therefore maintained in the final rule.
     Comment;  Several commenters  (IV-D-04; IV-D-10; IV-D-34;
IV-D-40; IV-D-42) were concerned that the submittal date  (no
later than 90 days after the  date  of promulgation) for the
initial report did not allow  enough time for owners and
operators to prepare for, or  the State and local authorities
to assume delegation of, the  NESHAP for such notification.
Two commenters (IV-D-04; IV-D-34)  suggested that the submittal
date for the initial report should be changed to "no later
than 270 days after promulgation," or 9 months.  Another
commenter  (IV-D-10) requested an extension to at least
6 months after promulgation.  Another commenter  (IV-D-40)
suggested that the initial notification requirement be
extended to  6 or 9 months and noted that the dry cleaning
standards initial compliance  notification was extended to
270 days.
     Response;  The EPA concurs that 90 days may not allow
enough time  for all owners and operators of halogenated
solvent cleaning machines to  learn of and prepare for the
NESHAP initial report.  The EPA has extended the required
submittal date of the initial notification report for existing
sources from "no later than 90" to "no later than 270" days
after promulgation of the rule.  New sources  for which
construction or reconstruction had commenced  and initial
startup had  not occurred before the date of promulgation must

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submit the report as soon as practicable before startup but no
later than 60 days after the promulgation date.  New sources
for which the construction or reconstruction commenced after
the date of promulgation shall submit the report as soon as
practicable before the construction or reconstruction is
planned to commence.
     Comment:  Three commenters (IV-D-08; IV-D-20; IV-D-29)
stated that recordkeeping and reporting should only be
required when the information is specifically used to
demonstrate compliance with the regulation.  One commenter
(IV-D-08) was concerned that the initial reporting
requirements exceed the minimum required to determine if the
cleaning machine in question is subject to, and complying
with, the rule.
     Response:  The EPA has reevaluated reporting and
recordkeeping requirements.  As discussed in a previous
response, some of these requirements have been changed based
on this evaluation.  The final rule only includes the minimum
recordkeeping and reporting necessary to demonstrate
compliance with the regulation.  The proposed initial
reporting requirements were similar to the requirements stated
in the NESHAP General Provisions.   Differences between the
General Provisions and the proposed Halogenated Solvent
Cleaner NESHAP requirements include the following:
     (1)  The halogenated solvent cleaner NESHAP requires an
estimate of the yearly consumption of halogenated solvents for
each solvent cleaning machine, and
     (2)  The General Provisions require that the report
include a statement as to whether the affected source is a
major or area source.
     The EPA has determined that annual solvent consumption
estimates are necessary to ensure compliance with the rule.
These estimates are necessary for the EPA to assess whether
there may be a compliance problem (e.g., poor work practice
compliance, leaks).  Therefore, this requirement has been
maintained in the final rule.  The EPA has also included the

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General Provision requirement of a statement as to whether the
affected source is a major or area source to reduce confusion.
     Comment;   One commenter (IV-D-42) suggested that there be
no requirements for submittal of information during the time
period when State and local agencies are submitting requests
for delegation of authority to administer the federal
standard.
     Another commenter (IV-D-02) stated that § 63.467(e) of
the proposed rule should specify that the annual control
device monitoring report be sent to the EPA unless a State has
accepted delegation of subpart T through the 112(1) program.
     Response;  The initial notification submittal deadline
for new cleaners in the final rule was increased from 90 to
270 days after promulgation.  If there has been no delegation
of authority by the EPA to the State or local level, the
regulatory authority is maintained with the EPA and reports
are to be sent to the EPA.
     Comment;   Two commenters (IV-D-21; IV-D-31) stated that
the submittal date for the initial statement of compliance
should be extended.  One commenter (IV-D-31) stated that they
believed that compliance activities begin on the compliance
date and they were confused because the results of the first
3-month rolling average emissions calculation would not be
available within 30 days of compliance.  Another commenter
(IV-D-21) suggested that the 30-day submittal date should be
revised to "90 days after the compliance date specified in
section 63.460(b) and  (c)."
     Response;  The EPA agrees that 30 days may not be
adequate time to complete the initial compliance activities
and submit an initial compliance report.  Therefore, the
provisions in the final rule were changed to 150 days after
the compliance date.
     Comment;  One commenter (IV-D-22) recommended that
§ 63.466(c) of the proposed rule allow recordkeeping in either
written or electronic form.
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     Response:  The EPA agrees with the commenter that
recordkeeping should be allowed in either written or
electronic form.  The final rule has been clarified to allow
for recordkeeping in either written or electronic form.  This
requirement is consistent with the General Provisions
[§ 63.10(b)(l)].
     Comment;  Four commenters (IV-D-20; IV-D-25; IV-D-29;
IV-D-35) stated that reporting directly to the regulatory
agencies should only be required if retaining records on-site
is not sufficient to demonstrate compliance with the
regulation (e.g., title V operating permit sources).  One
commenter  (IV-D-25) requested that the records required by the
control device monitoring report [§ 63.467(e) of the proposed
rule] and the solvent consumption report [§ 63.467(f) of the
proposed rule] remain on-site and not be submitted to the
Administrator or the agency to which enforcement is delegated.
One commenter (IV-D-35) stated that in New Jersey, operators
are required to keep records of solvent usage, but do not have
to submit them.
     Response:  The EPA reevaluated the minimum reporting and
recordkeeping requirements needed to demonstrate compliance.
The EPA has promulgated the minimum reporting requirements
necessary to demonstrate compliance with the rule.  Solvent
consumption or monitoring measurement records need to be
reported to the regulatory agency to verify compliance with
the rule.  Therefore, the proposed reporting requirements have
not been modified in the final rule.  Furthermore, 40 CFR Part
70 (State Operating Permit Program) submittal of reports of
any required monitoring are required every 6 months
[§ 70.6(a)(3)(iii)(A)].
     Comment;  Two commenters (IV-D-06; IV-D-33) stated that
the reporting requirements for conveyorized and open top vapor
degreasers should be consistent with 40 CFR part 70.  The
commenter also stated that, although § 63.467(g) of the
proposed rule is not in direct conflict with 40 CFR part 70, a
provision should be added stating that more frequent reporting

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of exceedances may be required by the States in an operating
permit.
     Response;  The EPA acknowledges that the State, under
40 CFR Part 70, may require more frequent reporting than
required under the proposed and final rule.  For example,
40 CFR Part 70 requires submittal of reports of any required
monitoring every 6 months [§ 70.6(a)(3)(iii)(A)].  Under
40 CFR Part 70, exceedances require "prompt" reporting, where
the regulatory authority defines the degree and type of
exceedance likely to occur and the applicable requirements
[§ 70.6(a)(3)(iii)(B)].
     Comment;  Several commenters (IV-D-08; IV-D-22; IV-D-25;
IV-D-52; IV-D-54) requested that an alternative to the
requirements of § 63.466(a)(l) and  (2) of the proposed rule be
provided for owners of existing cleaning machines who may no
longer possess an owners manual or may not be able to trace
the date of installation of their machines or controls.  One
commenter (IV-D-08) suggested that the EPA allow owners to
submit a written set of procedures as a substitute for an
owner's manual.  The commenter also suggested that, in place
of installation records, the EPA allow the owner to certify
that the machine and/or its controls were installed prior to
the proposal date.  Another commenter  (IV-D-54) suggested
deleting the requirement that owner's manuals must be
maintained for the lifetime of the machine.
     Response;  The EPA acknowledges that a number of owners
and operators of existing halogenated solvent cleaning
machines may not have an owners manual or may not be able to
trace the date of installation of their machines or controls.
The EPA's intent was to offer an owner or operator a simple
method from which an equipment compliance determination can be
made and documented.  Therefore, in the final rule, the EPA
has allowed the owner or operator to substitute written
maintenance and operating procedures in lieu of an owners
manual.  In situations where an installation report is
unavailable,  the owner or operator can substitute a

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certification that the machine and/or its controls were
installed prior to or after the proposal date.
     Comment;  One commenter (IV-D-54) asked for more details
on what information the EPA would require from owners or
operators of solvent cleaners to demonstrate that the cover
requirements are being met.
     Response;  The EPA proposed that an owner or operator of
a halogenated solvent cleaning machine choosing to comply with
the equipment and work practice standard must include, in an
annual report, a monthly inspection record of the cover to
ensure that it is free of cracks, holes, or other defects
[§ 63.465(b)(2) of the proposed rule].  This can be done
through a visual inspection of the cover when it is in the
closed position and must be documented in a log.  The EPA also
proposed that an operator test be required to demonstrate that
the work practice requirements (including the use of a cover)
of the rule are understood.  Enforcement and validation of
work practice compliance is difficult.  The EPA evaluated a
number of options and determined that the proposed
requirements were the most reasonable requirements for owners
and operators of solvent cleaners to demonstrate compliance
with cover requirements.  These proposed requirements have
been maintained in the final rule.
     Comment:  Two commenters (IV-D-35; IV-D-40) stated that
some sources should be exempt from reporting requirements.
One commenter  (IV-D-40) recommended that the EPA exempt batch
vapor cleaning machines of less than 0.60 square meters
(6.5 square feet) from annual reporting requirements,
quarterly exceedance reporting,  and the permitting
requirements of the proposed standards.  Another commenter
(IV-D-35) recommended that the reporting requirement for area
sources be waived.
     Response;  The EPA has not exempted batch vapor cleaning
machines with a solvent/air interface area of less than
0.60 square meters from reporting and Title V Operating Permit
Program permitting requirements.   These small cleaning

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machines could be a significant halogenated HAP emission
source within a major HAP emission source and must therefore
be subject to reporting and permitting requirements.
     Comment;  One commenter (IV-D-35) recommended that the
recordkeeping and reporting requirements be put into a table
for each option available for major sources.
     Response;  The EPA agrees that presenting the
recordkeeping and reporting requirements in a summary table
would inform owners and operators of halogenated solvent
cleaning machines of the options available to them in a less
confusing, more comprehensive manner.  The EPA is currently
developing a guidance document to the final rule to aid owners
and operators of halogenated solvent cleaning machines in
compliance with this rule.  This guidance document will
include a summary table of the recordkeeping and reporting
requirements for the various compliance options.
     Comment;  One commenter (IV-D-35) recommended that, for
major sources, States should be given the option of
coordinating the NESHAP-required reports with State emission
reporting requirements for VOC.
     Response;  The EPA agrees that, as long as the State
emission reporting requirements for VOC are at least as
stringent as the NESHAP requirements and all information
necessary to demonstrate compliance is included, States should
be given the option of coordinating the two reports.  The
General Provisions state that if a State requires a report
containing all the information required in a report required
for the NESHAP, that report may be submitted to satisfy the
requirements of the NESHAP  [§ 63.I0(a)(3)].
     Comment;  One commenter (IV-D-21) recommended that
separate recordkeeping requirements should be required for
"area" and "major" sources.
     Response;  The EPA does not believe that recordkeeping
requirements for area sources should differ from those
required for major sources.  A halogenated solvent cleaning
machine of the same size, design, and operating schedule at an

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area source has the same potential to emit as one at a major
source.  The proposed recordkeeping requirements are the
minimum determined necessary to demonstrate compliance, and
are considered to be reasonable.
     Comment;   One commenter (IV-D-31) requested that if an
initial report is required, it should be a simple, one-time
obligation, with no requirement to submit updates.
Specifically,  the commenter requested that § 63.467(a) and (b)
of the proposed rule be revised so that those facilities with
5 or more halogenated solvent cleaning machines could submit
one report for all cleaning machines.
     Response;  The proposed and final initial report
requirement [§63.467(a) of the proposed rule] is a simple
report that allows for a facility with a number of halogenated
solvent cleaning machines to submit one report including
separate information on each of their machines.  Updates to
the initial report are only required to notify the EPA of an
installation of a new source.
     Comment;   Two commenters (IV-D-20; IV-D-29) stated that
the following should be included in the reporting and
recordkeeping section of the final regulation:
     "(a)  Each owner or operator of a batch vapor or
     in-line solvent machine shall maintain records of
     the results of control device monitoring for a
     period of 5 years."
     Response:  The General Provisions require that a source
maintain records of all information in permanent form for
5 years following occurrence.  The proposed regulation already
included a statement analogous to that suggested.
Section 63.466(b) of the proposed rule states the following:
     "(b)  Each owner or operator of a batch vapor or in-line
solvent cleaning machine complying with the provisions of
63.462 shall maintain records of the results of control device
monitoring required under § 63.465(a), (b), (c), and/or (d)
either in computerized or written form for a period of
5 years."
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     The EPA has maintained a similar statement in the final
rule except that the word "computerized" has been changed to
"electronic."
     Comment;  Two commenters (IV-D-20; IV-D-29)  recommended
adopting a requirement that the source develop and implement a
broad operation and maintenance (O&M) plan that would cover
many of the recordkeeping and monitoring requirements in a
simpler manner.
     Response;  The recordkeeping and monitoring requirements
contained in the final rule are the minimum necessary to
demonstrate compliance.  The additional burden of an O&M plan
is not warranted.  The EPA is preparing a guidance document
that will aid owners or operators with the recordkeeping and
monitoring requirements of the final rule.
     Comment;  One commenter (IV-D-51) stated that owners or
operators complying with the NESHAP through the use of the
control equipment option should not be required to collect
solvent consumption data.
     Response;  The requirement contained in § 63.467(a)(4) of
the proposed rule, requiring an estimate of the yearly
consumption of halogenated solvents for each solvent cleaning
machine in the initial notification report, has been retained
in the final rule.  In addition, the annual compliance reports
require a yearly estimate of halogenated solvent consumption.
The EPA has decided that the inclusion of a solvent
consumption estimate is necessary to help identify whether
there may be compliance problems (e.g., leaks, poor work
practices).
2.8.2  General Provisions
     Comment:  Two commenters (IV-D-08; IV-D-32)  requested
that the EPA consider exempting all halogenated solvent
cleaning machine sources from all subpart A (General
Provisions) requirements because of duplication of effort and
general confusion.
     Response;  Owners or operators who are subject to a
subpart promulgated for a specific source category under

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section 112(d),  112(f), or 112(h) of the Act are also subject
to the requirements of the NESHAP General Provisions.
Therefore, halogenated solvent cleaning sources subject to the
rule must comply with the NESHAP General Provisions.  The
General Provisions were developed to eliminate the repetition
of general information and requirements within the subparts.
They have the legal force and effect of standards, and they
may be enforced independently of re?evant standards, if
appropriate.   In the final rule, the EPA has overridden those
sections of the NESHAP General Provisions that do not apply to
halogenated solvent cleaning sources.  Batch cold cleaning
machines have less requirements than batch vapor and in-line
cleaning machines.  The table in appendix C of the final rule
summarizes which sections of the General Provisions apply to
the rule and which have been overridden.
     Comment;  One commenter (IV-D-19) stated that the EPA
should exempt area source batch vapor and in-line cleaning
machines from the General Provisions' startup/shutdown
planning and other preconstruction notification recordkeeping
and reporting requirements.  The commenter requested that the
initial notification procedure provided in § 63.467 of the
proposed rule be required in lieu of the preconstruction
notification requirements of the General Provisions.  The
commenter stated that the small emissions from these sources
do not justify the administrative burden of the weekly
startup/shutdown procedures.  The commenter suggested that an
annual report describing solvents used and removed would be
far more appropriate and stated that the EPA could create a
less onerous procedure for such de minimis sources.
     Response;  The proposed and final rule contain provisions
for startup and shutdown of vapor cleaning machines.  The
startup, shutdown, or malfunction provisions contained in the
NESHAP General Provisions in section 63.6(e)(3),
63.10(e)(5)(i),  and 63.10(d)(5)(ii) have been overridden in
the final rule.
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     Comment:   Several commenters (IV-D-20; IV-D-29; IV-D-42;
IV-D-54)  stated that the General Provisions are too burdensome
for area sources and that the requirements should be
simplified.  Two commenters (IV-D-20; IV-D-29) suggested that
it would be useful to override the General Provisions and
allow the regulating agency the choice to determine what
information is necessary to assure compliance with the
regulation.  One commenter (IV-D-19) requested that the EPA
clarify that new and reconstructed batch cold cleaning
machines are subject only to the initial reporting
requirements of § 63.467(b) of the proposed rule so that there
is not any confusion regarding cold cleaning machines being
subject to the initial notification requirements of the
General Provisions.
     Response;  As described in a previous response, a source
that is subject to the halogenated solvent cleaning NESHAP is
also subject to the NESHAP General Provisions.  This includes
both area and major sources subject to the NESHAP.  The
initial notification report in the final rule is similar to
the reporting requirements in the General Provisions.  The EPA
has evaluated what portions of the General Provisions to
override.  Those sections of the General Provisions that are
overridden in subpart T are presented in the table in
appendix C of the final regulation.
     Comment:  One commenter (IV-D-31) requested that the EPA
reopen this rule for comments on the applicability of
subpart A  (General Provisions) once that subpart is final.
The commenter stated that it is the EPA's responsibility to
provide this opportunity for effective comment as promised by
the Administrative Procedure Act, and by comparable
requirements in the Act.
     Response:  The NESHAP General Provisions (Subpart A)
applies to all those regulations subject to subsequent
subparts of part 63  [including subpart T], except if
overridden  [§ 63.1(a)(4)].  The General Provisions were
proposed and public comment was taken.  The General Provisions

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are final after an effective comment period, as dictated by
the Administrative Procedure Act and the Act.  The EPA will
not be reproposing the rule to receive comments on the
applicability of subpart A.  However, all changes in the final
General Provisions were evaluated for their impact on the
final NESHAP for halogenated solvent cleaners and have been
accounted for in the final NESHAP.
2.8.3  Solvent Consumption
     Comment;  Three commenters (IV-D-08; IV-D-21; IV-D-36)
stated concerns regarding the reporting of solvent
consumption.  Two commenters (IV-D-08; IV-D-36) stated that it
was unclear whether the "yearly consumption" of solvent was to
be the amount of halogenated solvent added to the machine, or
the amount emitted.  The commenter was concerned that if an
owner or operator is to report on the amount emitted, it would
be too burdensome.  The commenter suggested that the report be
made in mass units (Ibs, kg) and be reported for each type of
halogenated solvent added to the machine so that the EPA can
estimate the amount of halogenated solvent emitted, in total
or by type.  The commenter further stated that it may be
useful for the EPA to obtain material safety data sheets or
some other information concerning the blend of constituents
for the solvents and mixtures purchased or added to the
machines.
     Response:  The yearly consumption requirement is intended
to be the amount of solvent that has been added to each
solvent cleaning machine.  This information will assist
compliance personnel in identifying potential problems.  The
requirement for the reporting of yearly solvent consumption
has been retained in the final rule.
2.8.4  Exceedance Report
     Comment;  One commenter (IV-D-10) stated that the
proposal does not encourage honest and truthful reporting of
exceedances.  The commenter stated the following:
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     (1)  The EPA should specify more clearly what constitutes
noncompliance, and the consequences, if any, of submitting an
exceedance report as required by the proposal;
     (2)  The EPA should allow a source the opportunity to
make repairs within a specified time period, and if
successful, the source should not have to submit an exceedance
report;
     (3)  The EPA should specify whether the submission of an
exceedance report will result in a fine or other sanction, and
whether the inclusion of a description of successful repairs
will be sufficient to ensure that no action will be taken
against the reporter; and
     (4)  The EPA should use a cooperative approach as opposed
to an adversarial approach, in assessing any penalties for
noncompliance.  In addition, the EPA should establish a policy
that no penalty will be imposed for any initial exceedance, as
long as the company is willing to work diligently toward
correcting the situation.
     Response;  It is in a source's best interest to address
exceedances as soon as possible to reduce their potential
liability.  The responsiveness of the source will likely be
taken into account when determining what appropriate
enforcement action to take.  Not all exceedance reports will
necessarily result in a penalty.  If an exceedance occurs, a
report describing the exceedances and the repairs made must be
submitted to the regulatory authority in the quarter in which
the exceedance occurs.  An exceedance occurs when a source
violates an applicable emission limit or standard, except when
a provision promulgated or approved by the Administrator
exempts such a condition as a federally enforceable violation,
such as a malfunction.  Sections have been added to the final
rule that delineate what constitutes an immediate exceedance
and what becomes an exceedance if it is not corrected within a
15 day timeframe.  The designated regulatory authority for the
rule will determine when a violation necessitates a fee.
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     Comment;  One commenter (IV-D-34) stated that the EPA
should allow owners or operators the opportunity to document
adjustments or repairs to the equipment in lieu of a quarterly
report for any exceedance or noncompliance to avoid an
unnecessary reporting burden for both equipment operators and
EPA personnel.  The commenter suggested that reporting be
required only for chronic noncompliance and gross exceedances
of emission limits.
     Response;  The EPA has reviewed the General Provision
requirements for the reporting of exceedances.  To make the
rule consistent with the General Provisions, the rule has been
modified to require biannual exceedance reports, if there is
not an exceedance, and quarterly exceedance reports, if there
has been an exceedance.  After a full year of compliance
without an exceedance, biannual exceedance reporting can be
resumed.
     Comment;  One commenter (IV-D-54) requested clarification
on whether the quarterly exceedance report required in
§ 63.467 of the proposed rule is part of the enhanced
monitoring report required under 40 CFR part 64.
     Response:  Clarification that the exceedance report is
not part of the enhanced monitoring report under 40 CFR
part 64 is made here.
2.9  OPERATING PERMIT PROGRAM
     Comment;  One commenter (IV-D-19) suggested that, to
avoid any confusion, the EPA should state in the text of the
final NESHAP that batch cold cleaners are not subject to
title V permitting requirements.  The commenter argued that
although the preamble made clear its intent to exempt batch
cold cleaning machines from title V permitting requirements,
the text of the proposed NESHAP only excludes batch cold
cleaning machines from that portion of the General Provisions
requiring compliance with permitting rules.  The commenter
stated that this approach may lead to confusion since EPA's
final rule for the operating permit program appear to require
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a specific EPA determination in order to exempt § 112 area
sources.
     Response;  The EPA has added provisions to the reporting
and recordkeeping section of the final rule that state that
batch cold halogenated HAP solvent cleaning machines located
at nonmajor sources are not subject to title V permitting
requirements.
     Comment:   Five commenters (IV-D-02; IV-D-17; IV-D-19;
IV-D-27; IV-D-33) requested that the EPA consider exempting
additional sources from title V permit provisions.
     One commenter (IV-D-17) requested that the applicability
section (§ 63.460 of the proposed rule) exempt area source
emission units from Act title V permit requirements.  States
generally issue permits for facilities only, and requiring a
title V permit for an area source at a facility that would
otherwise not have to get a title V permit would be
burdensome.  Two other commenters (IV-D-02; IV-D-19) stated
that the EPA should, as with batch cold cleaning machines,
exempt area batch vapor and in-line cleaning machines from
title V requirements because of the complexity, expense, and
overall burden it would place on small area source facilities,
     Another commenter (IV-D-33) recommended that a cutoff
level within the small degreasing subcategory be established
so that small businesses are not required to submit to
unreasonable administrative and compliance requirements.  The
commenter believed that sources with a solvent-vapor air
interface smaller than 10 square feet should be exempt from
the title V permit process; however, other reporting
requirements may be necessary for these sources to ensure
compliance with minimum control requirements.  Another
commenter  (IV-D-27) suggested a size cutoff of 10 tons of
emissions per year.
     Response;  The EPA has exempted batch cold cleaning
machines located at nonmajor sources from title V Operating
Permit Program requirements in the final rule.  Under
CFR 40 Part 70, nonmajor HAP sources are exempt from

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permitting requirements for 5 years.  The EPA has not exempted
any other halogenated solvent cleaning machine from permitting
requirements in the final rule.
2.10 CLARIFICATIONS
2.10.1  Definitions
     Super-Heated Vapor
     Comment:  Four commenters (IV-D-25; IV-D-31; IV-D-34;
IV-D-40) suggested revisions to the definition of SHV.  Two
commenters (IV-D-34; IV-D-40) stated that the definition for
"SHV system" is incorrect.  It should state that super-heated
vapors are generated by heating the vapors, not the liquid
solvent.  One commenter (IV-D-40) mentioned that super-heated
vapors may be applied using recirculating or static systems.
     Several commenters (IV-D-31; IV-D-34; IV-D-40) stated
that the definition for SHV should specify the units
(degrees F or C).   One commenter (IV-D-31) recommended  that
the EPA use the Celsius scale, because that is the scale most
commonly used in engineering.
     One commenter  (IV-D-25) stated that the definition for
SHV should be clarified by stating that the super-heated area
is for cleaned parts to pass through before exiting the
machine so as to evaporate the liquid solvent on them.
Another commenter (IV-D-31) stated that in the definition of
"SHV system" the "more than 1.5 times greater" than the
solvent boiling point should be changed to read "more than 1.5
times" the solvent boiling point.
     Response;  The EPA has modified the definition of SHV
system to incorporate the comments received.  The definition
of SHV system has been changed to read as follows:
          Super heated vapor system means a system that
     heats the solvent vapor, either passively or
     actively, to a temperature above the solvent's
     boiling point.   Parts are held in the super heated
     vapor before exiting the machine so as to evaporate
     the liquid solvent on them.   Hot vapor recycle is an
     example of a superheated vapor system.
     In the standards section of the rule it is stated that,
if SHV is used to comply with the rule, the owner or operator

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must ensure that the temperature of the solvent vapor at the
center of the superheated vapor zone is at least 12°C (10°F)
above the solvent's boiling point.
     Manual Cover
     Comment:  Two commenters  (IV-D-29; IV-D-35) believe that
the definition of cover should state that the cover needs to
completely seal the cleaner openings when in place and must be
free of cracks, holes, and other defects, and that the cover
should be designed to easily open and close without disturbing
the vapor zone.  One commenter (IV-D-29) pointed out that if
the definition is changed, then the information can be removed
from the standard.
     Response:  The EPA has clarified the definition of a
cover in the final rule.  The EPA has not added the verbiage
suggested by commenters IV-D-29 and IV-D-35 to the cover
definition.  The EPA has determined that this language is more
suitable in the standards section of the rule.  The definition
of a cover reads as follows:
          Coyer means a lid, top, or portal cover that
     shields the solvent cleaning machine from air
     disturbances when in place and is designed to be
     easily opened and closed without disturbing the
     vapor zone.  Air disturbances include, but are not
     limited to, lip exhausts, ventilation fans, and
     general room drafts.  Types of covers include, but
     are not limited to, sliding, biparting, and roll-top
     covers.
     Primary Condenser
     Comment:  One commenter  (IV-D-40) recommended that the
definition of  primary condenser be revised to note that
primary condensers typically do not circulate refrigerant.
     Response;  The EPA has modified the definition of primary
condenser to indicate that they circulate or recirculate a
chilled substance.
     Carbon Adsorption Systems
     Comment;  One commenter  (IV-D-40) stated that a
definition for a carbon adsorption system should be added.
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     Response;  The EPA has added a definition for a carbon
adsorber to the definitions section of the final rule.
     Cold Cleaning Machine and Solvent Cleaning Machine
     Comment;   Three commenters (IV-D-15; IV-D-16; IV-D-25)
provided comments on the definition of cleaning machine.  One
commenter (IV-D-25) requested that the EPA clarify that
solvent cleaners which employ heated, but non-boiling, solvent
are considered cold cleaners.  One commenter (IV-D-16)
recommended adding the phrase, "This definition does not
include remote-reservoir cleaning devices,"  to the
definitions for cold cleaning machine and solvent cleaning
machine.
     Response;  The EPA has clarified in the cold cleaning
machine definition that cleaning machines that use heated,
non-boiling, solvent are considered cold cleaning machines.
The EPA has not added the verbiage, suggested by commenter
IV-D-16, to the cold cleaning machine and the solvent cleaning
machine definitions.  The cold cleaning machine and the
solvent cleaning machine definitions do include
remote-reservoir cleaning machines that use solvent with a
halogenated HAP solvent content of greater than 5 percent by
weight.
     The solvent cleaning machine definition has been modified
to state that it is "any device or piece of equipment that
uses halogenated HAP solvent liquid or vapor..."
     Existing and New
     Comment;   Two commenters (IV-D-15; IV-D-31) presented
alternative definitions for "new" and "existing."  One
commenter (IV-D-15) stated that the definitions of "existing"
and "new" in § 63.460(d) and (e) and § 63.461 of the proposed
rule are inconsistent.  The commenter recommended that the
definition for "existing" read as follows:
     "Existing means any solvent cleaning machine that
     commences construction or reconstruction before
     November 29, 1993."
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     Two commenters (IV-D-15; IV-D-31) recommended that the
definition for "new11 read as follows:
     "New means any solvent cleaning machine, the
     construction or reconstruction of which is commenced
     on or after November 29, 1993."
     Response;  The definition of "existing" has been written
similar to the definition suggested by commenter IV-D-15.  The
definition for "new" is consistent with the General Provisions
and has not been changed.
     Solvent/Air Interface
     Comment;  Two commenters (IV-D-06; IV-D-20) stated that
the term solvent/air interface should be more precisely
defined in relation to a readily identifiable physical
location on the solvent cleaning machine (such as the bottom
of the primary condenser coil or the mid-line of the primary
condenser).
     Response;  The solvent/air interface has been defined in
relation to the mid-line of the primary condenser coil(s) in
the final rule.
     Reduced Room Draft
     Comment;  One commenter  (IV-D-40) stated that RRD should
be defined as the reduction of the air flow across the top of
the freeboard area of the cleaning machine.  Otherwise
enclosed cleaners would still be required to reduce air flows
outside of the machine.
     Response;  The definition of RRD has been modified to
read, "means decreasing the flow or movement of air across the
top of the freeboard area of the solvent cleaning machine..."
     Freeboard Height
     Comment;  One commenter  (IV-D-45) recommended that the
freeboard height definition be further clarified by modifying
the first sentence to read, "freeboard height means the
distance from the solvent/air interface to the top of the
cleaning machine as measured during the machine's idling
mode."  The undisturbed vapor blanket is a condition occurring
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only during the idling mode, so freeboard height is measured
only during this mode.
     Response:  The EPA agrees that clarification of the
definition of the freeboard height as being as measured during
the machine's idling mode is necessary for vapor cleaning
machines.  Therefore, the definition of freeboard height has
been modified as recommended by the commenter.
     Freeboard Refrigeration Device
     Comment;  One commenter (IV-D-50) stated that the
definition for "freeboard refrigeration device" should be
revised to include an adequate primary condensing system.
     Response;  The freeboard refrigeration device definition
has not been changed as requested by the commenter.  However,
in the standards the EPA has added that a super-cooled primary
condenser that meets the requirements of a freeboard
refrigeration device is equivalent to a freeboard
refrigeration device.
     Solvent Blend
     Comment:  One commenter (IV-D-55) stated that a
definition should be added for "solvent blend."
     Response;  The term "solvent blend" has been removed from
the rule and, therefore, is not defined in the final rule.
2.10.2  Toxicitv
     Comment;  Two commenters (IV-D-10; IV-D-31) had several
comments related to toxicity.  One commenter (IV-D-10) stated:
     (1)  The preamble inaccurately states that MC and TCE are
both classified as probable human carcinogens (Group B2
carcinogen).  Trichloroethylene is currently under review by
the EPA and is considered to lie somewhere along a continuum
between Groups B2 and C as a possible human carcinogen;
     (2)  Toxicity information on long-term exposure to PCE
and TCE discussed in the preamble was based on animal studies
at very high exposure dose levels, and adverse effects are not
expected at occupational or environmental exposure levels; and
     (3)  The central nervous system function impairments from
short-term exposure to MC discussed in the preamble are

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transitory and are typical for both halogenated and
nonhalogenated solvent exposure.
     The commenter requested that the discussion of the EPA's
risk analysis be revised to include a statement noting that
the real risk is unknown and may be zero.  The commenter
stated that the statements of risk in the preamble were
unqualified and misleading and that according to EPA's risk
assessment guidelines, "the true value of the risk is unknown,
and may be as low as zero."
     Another commenter (IV-D-31) provided the following
clarifications on the discussions of solvent toxicity in the
preamble:
     (1)  The preamble should state that the cancer
classification for TCE is under review by the EPA;
     (2)   The word "transitory" should be inserted before the
word "impairments" in the phrase "(MC) has been known to cause
impairments" in the discussion of MC toxicity;
     (3)  The preamble should state that the health effects
data for PCE and TCE, which show adverse effects in the liver
and kidneys, are based largely on animal studies conducted at
high dose levels.  Kidney and liver effects as well as
fetotoxicity would not be expected at appropriate exposure
levels  (below permissible exposure level [PEL]/threshold limit
value [TLV]); and
     (4)  The EPA's discussion of the analysis of potential
lifetime human cancer risk should include two things.  First,
that the risk estimates are based on high-dose animal studies
using the conservative linearized multistage model.  Second,
according to the EPA's own cancer risk assessment guidelines,
the real risk is unknown and may be zero.
     Response;  Methylene chloride is considered a. probable
human carcinogen and is currently classified as a Group B2
carcinogen; however, the EPA agrees that TCE lies somewhere
along a continuum between Group B2 and C as a possible human
carcinogen.  The EPA continually adjusts these classifications
when warranted by additional data.  There are new data in a

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follow-up NIEHS study associating MC with pancreatic tumors in
workers and liver tumors in female mice.  There is also data
that indicates that MC exposure may have genotoxic effects.
     In cancer studies, high doses are used to elicit a
response in a small number of animals.  The EPA disagrees that
the adverse effects observed in high dose animal studies would
not be expected at occupational or environmental levels.
While one may not readily observe adverse effects in the
general population, the impact on sensitive sub-populations
must be considered, as well as the repeated exposure to
multiple pollutants that may have an additive effect.
     The EPA agrees that the central nervous system function
impairments associated with short-term exposure to solvents
such as MC are transitory; however, transitory effects
nevertheless can be of serious concern under certain
scenarios.  The Act directs the EPA to address transitory
health effects as well as non-transitory effects.
     The EPA agrees that "the true value of the risk is
unknown, and may be as low as zero" but, as also stated in the
Guidelines for Carcinogen risk Assessment (51 FR 33 992,
September 24, 1986), "the linearized multistage procedure
leads to a plausible upper limit to the risk consistent with
some proposed mechanisms of carcinogenesis."  Therefore, the
EPA has not revised the risk analysis as requested by the
commenter.
     The EPA agrees that the cancer classification for TCE is
under review by the EPA.  The EPA also agrees that the word
"transitory" should be inserted before the word "impairments"
in the phrase "(MC) has been known to cause impairments."
However, the clarification on MC toxicity given above should
be noted.  These clarifications have been noted.  However,
since the EPA is not republishing the proposal preamble, the
proposal preamble has not been changed.
2.10.3  Wording of Regulation
     Comment;  One commenter (IV-D-21) supported the EPA's
proposal to allow for equivalent control technologies and

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methods of compliance.  The commenter recommended that
§§ 63.462 and 63.463 of the proposed rule be revised to
include the following language where appropriate:
     "Except as provided for in [sections] §§ 63.463 and
     63.468, each existing, new, or reconstructed batch
     vapor or in-line solvent cleaning machine shall
     conform to the following..."
     Response;  The wording suggested by the commenter is
misleading in that it leads one to believe that the equivalent
methods of control section is an alternative to § 63.462 of
the proposed rule.  The EPA did not intend for the equivalent
methods of control section to serve as an alternative to the
standards.  In terms of the equipment standard, the section is
meant to provide a means to comply using other equivalent
controls not specifically listed.  To clarify this, the rule
has been modified by adding the following statement to the
equipment standard provisions of the final rule:
     "...or other equivalent methods of control as
     determined using the procedure in the equivalent
     methods of control section..."
     Applicability
     Comment;  Three commenters (IV-D-20; IV-D-29; IV-D-35)
requested that the EPA specifically state in the applicability
section that the rule applies only to batch vapor and in-line
cleaning machines, and batch cold cleaning machines.
     Response;  The EPA has clarified in the applicability
section that the rule applies to batch vapor, in-line vapor,
in-line cold, and batch cold cleaning machines that use
halogenated HAP solvents.
     Comment:  Three commenters (IV-D-20; IV-D-29; IV-D-35)
suggested the use of a table, outlining a simple compliance
schedule in place of § 63.460(b), (c), (d) and  (e) of the
proposed rule.  The schedule would be much easier to
comprehend and would help owners/operators determine if their
equipment is affected by this rule.
     Response;  The EPA believes that § 63.460(b),  (c),  (d)
and  (e) of the proposed rule are clearly worded and therefore
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will not be removed.  The EPA is producing a guidance document
for the rule that will contain an easy to follow compliance
schedule presented in table format.
     Reporting
     Comment;  One commenter (IV-D-31) stated that in
S 63.467(c)(3)(ii) of the proposed rule the word "required"
should be changed to "needed."
     Response:  In § 63.467(c)(3)(ii), the word "required" has
been changed to "necessary" as this more clearly represents
the EPA's intent.
     Other
     Comment:  One commenter (IV-D-31) stated that every time
the rule uses the words "cleaning machine," the EPA should add
the words "subject to this subpart."
     Response;  The applicability section of the rule states
which sources are subject to the rule.  Any reference in the
rule to "cleaning machine" after the applicability section
assumes that the cleaning machine is subject to the rule.
     Typographical Errors
     Comment;  Two commenters (IV-D-36, IV-D-45) stated that
in § 63.467(c),  (d), and (e)  of the proposed rule the
reference to "§ 63.460(b) and (c)" should read "§ 63.460(d)
and (e)."
     Response:  This correction has been made.
     Comment;  One commenter (IV-D-30) stated that the
equation in § 63.463(b)(4)  of the proposed rule does not
appear to have been printed correctly.
     Response;  The proposed rule does not contain a
§ 63.463(b)(4) as referred to by the commenter.  The EPA
assumes that the commenter intended to comment on equation 3
in § 63.464(b)(4) of the proposed rule.  In addition, the
commenter did not provide any information on the reasoning
behind the comment.  The EPA has reviewed equation 3 and has
determined that the equation appeared in the proposed rule in
its correct form.
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     Alternative Standard Wording
     Comment;  One commenter (IV-D-35) stated that the word
"may" in § 63.463(a) of the proposed rule should be changed to
"must."  This is to indicate that if owners/operators choose
the alternative standard, then they must comply with the
provisions set forth in the alternative standard.
     Response:  The change has been made as suggested by the
commenter.
2.10.4  Other
     Title of the Standard
     Comment:  Two commenters (IV-D-39; IV-D-43) stated that
the term halogenated encompasses five elements: fluorine,
chlorine, bromine, iodine, and astatine.  The commenters
(IV-D-39; IV-D-43) recommended that, since all six of the
solvents listed in the proposed rule  (MC, PCE, TCE, TCA, CT
or C) qualify as chlorinated solvents and no non-chlorinated
solvents are identified, the title of the standard should be
changed to "National Emissions Standards for Chlorinated
Solvents."
     Response;  The standards were written to cover
halogenated solvent cleaners, and were not written to cover
chlorinated HAP solvents unless they were halogenated.  The
final rule clarifies that MC, PCE, TCE, TCA, CT, or C used in
solvent cleaning machines in amounts greater than 5 percent by
weight are covered by the rule.  The title of the standard has
not been changed.
     CAS Number
     Comment:  One commenter (IV-D-15) recommended that, to
avoid any confusion, the EPA should include the CAS number for
each of the six solvents listed in §  63.460(a) of the proposed
rule.  These CAS numbers are as listed below:
     methylene chloride  -  (CAS No. 75-09-2)
     perchloroethylene  -  (CAS No. 127-18-4)
     trichloroethylene  -  (CAS No. 79-01-6)
     1,1,1-trichloroethane - (CAS No. 71-55-6)
     carbon tetrachloride -  (CAS No.  56-23-5)

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     chloroform - (CAS No. 67-66-3)
     Response;  The EPA has added the CAS numbers for each of
the solvents listed in § 63.460 of the proposed rule.
             ies Retained
     Comment :  Several commenters (IV-D-06; IV-D-20; IV-D-31)
stated that the authorities that shall be retained by the
Administrator and not transferred to a State should be
included in § 63. 460 (f) of the rule and be subject to public
comment .
     Response:  The EPA acknowledges that in many instances
the approval authority is delegated from the Administrator to
the Regions and the state/ local agencies.  However, in some
instances the EPA has chosen not to delegate similar authority
to the state/ local level.  The EPA has listed the authorities
that it will retain in § 63. 460 (e) and (f) of the final rule.
     Background Information Document
     Comment;  One commenter (IV-D-03) reported that she was
misquoted in the background information document.  The
commenter was guoted as stating that HCFC-123 caused cancer,
however, the commenter reports that she stated that HCFC-123
caused benign tumors,  not carcinogenic tumors.  The commenter
requested that this incorrect reference be removed.
     Response;  The EPA agrees that the BID stated that
HCFC-123 caused carcinogenic tumors in error.  However, the
BID has already been published (EPA-453/R-93-054) and
therefore cannot be changed.  A memorandum noting the error
has been placed in the docket.
     EPA Approval
     Comment :  Two commenters (IV-D-21; IV-D-30) stated that
in §§ 63. 465 (d) and 63.468 of the proposed rule it should be
clarified what will occur if the Administrator does not act on
an application for equivalency in time for the source to meet
the compliance schedule in the standard.   One commenter
(IV-D-21) suggested that a "default" clause should be added to
these sections that states that EPA approval is automatically
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given if a determination is not made within a specified time
frame.
     Response;   Verbiage detailing what occurs when the
Administrator receives an equivalency request has not been
added to the final rule because the General Provisions address
this issue.  Under section 63.6(g) of the General Provisions,
an owner or operator may apply to the Administrator to use an
alternative means of emission limitation.  If the reductions
in emissions are at least equivalent to the reduction achieved
under an equipment design, work practice, or operational
emission standard, the Administrator will publish in the
Federal Register a notice allowing the use of the alternative
emission standard and will allow an opportunity for public
comment on the alternative.  The final rule has been amended
to require that such an equivalency request by an existing
source must be made no later than 18 months after promulgation
of the standard.  This would allow sufficient time for the
Administrator to evaluate and approve or disapprove of an
alternative prior to the deadline for submittal of the initial
compliance report.  If an owner or operator requests to use an
alternative monitoring method, section 63.8(f)(5) of the
General Provisions requires the Administrator to notify the
owner or operator of approval or intention to deny approval of
the request within 30 calendar days after receipt of the
original request and within 30 calendar days after receipt of
any supplementary information that is submitted.
2.11 MISCELLANEOUS
2.11.1  Guidance Documents
     Comment;  One commenter  (IV-D-02) stated that they are
concerned  that the presentation of the regulation made it
difficult  to understand.  The commenter suggested that an
"easy-to-understand" regulation guidance document be produced.
     Response:  The EPA is producing a guidance document that
will be directed towards  small business owners or operators of
solvent cleaning machines.  The document will assist owners or
operators  to determine the applicability of the rule to their

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operations and to comply with the regulation.  This guidance
document is scheduled to be published early in 1995.
     Comment:  Two commenters (IV-D-10; IV-D-31) stated that
it would be useful for both the EPA and the source if the EPA
were to assist the source in evaluating its compliance
problems, and in determining the steps necessary for bringing
it into compliance.  One commenter (IV-D-31) stated that the
EPA should build an outreach program to help regulated
businesses find solutions to compliance difficulties.
     Response:  The EPA's Office of Air Quality Planning
Standard's Small Business Assistance Program has allocated
funds for the development of a guidance document to help
regulated businesses comply with the final rule.  This
document should be published early in 1995.
     Comment;  One commenter (IV-D-24) recommended that the
EPA produce a best management practices (BMP) guide for
halogenated solvents carburetor cleaning in lieu of inclusion
in the NESHAP.  The commenter stated that distribution to the
motor vehicle service industry could be provided through the
§ 507 small business assistance program and otherwise.  The
commenter suggests that the guide state that:  (1) halogenated
carburetor cleaning compounds only be used in batch cold
cleaning machines, (2) batch cold carburetor cleaning machines
have covers for use at all times, (3) halogenated carburetor
cleaning compounds only be used with water barriers, and
(4) that leaks be repaired expeditiously,  that solvent dragout
be kept to a minimum, and that spent solvents be recycled if
possible.
     Response;  The commenter has provided no basis for
exempting halogenated solvent carburetor cleaning machines
from this rule.  Therefore, the EPA has not removed carburetor
cleaning machines from the final rule.
     The EPA is preparing a guidance document that will assist
owners or operators of carburetor cleaning machines in
complying with this rule.
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2.11.2  Compliance
     Comment:   Eight commenters (IV-D-13; IV-D-22; IV-D-32;
IV-D-39; IV-D-40; IV-D-45; IV-D-52; IV-D-54)  requested a
revised compliance schedule.  One commenter (IV-D-52)  felt
that the compliance time period should be measured from the
date that the final rule is promulgated, rather than from
proposal.  Another commenter (IV-D-40) recommended that the
EPA stagger the compliance dates over a period of 18 to
36 months.  Several commenters (IV-D-13; IV-D-22; IV-D-32;
IV-D-39; IV-D-45; IV-D-51; IV-D-52; IV-D-54)  stated that the
compliance period should be extended from 2 years to 3 years
as allowed by the Act Amendments of 1990.  One commenter
(IV-D-13) requested the additional compliance time so that
they could have more time to test and validate an
aqueous-based cleaning machine they are evaluating for use as
a substitute to their present solvent-based system.  Two
commenters (IV-D-39; IV-D-45) stated that a three year
compliance period would be necessary in order to allow as many
sources as possible to achieve the optimum compliance approach
of HAP elimination.  One commenter (IV-D-32)  claimed that this
action will allow companies additional flexibility to
prioritize those compliance actions that have the highest
potential for environmental benefit.
     Response;  Commenter IV-D-52 is correct that the
compliance time period is measured from the date of
promulgation.  It is stated as such in § 63.460(e) of the
proposed rule.  In this section it states that existing
cleaning machines must comply with the rule "no later than
24 months after the date of promulgation of this subpart."
     The compliance time period has been extended from 2 years
to 3 years.  This will provide owners or operators of solvent
cleaning machines additional time to consider alternative
cleaning methods, determine the compliance option best suited
to their cleaning process, coordinate their regulatory
requirements under this rule with their other regulatory
obligations, and to come into compliance with the rule.

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     Comment:  Three commenters (IV-D-10; IV-D-22; IV-D-42)
requested that sources using HAP's that are scheduled to be
phased-out in 1996 be handled separately from the other HAP's.
Two commenters (IV-D-22; IV-D-42)  suggested that the
regulation should only apply to new solvent cleaning machines
using TCA, and that the same considerations should be given to
other ozone depleting compounds being phased out under the
Montreal Protocol or by presidential order.
     One commenter (IV-D-22) stated that TCA cannot be
stockpiled for long,  which would force owners/operators of
existing cleaning machines that use TCA to change processes or
apply for an essential-use exemption for TCA.  Flexibility for
the use of TCA should be built in the final regulations.
     Response:  The rule treats all halogenated solvents the
same whether they are being phased out or not.  The EPA sees
no reason to treat solvents that are being phased out
differently than other solvents.  By January 1, 1996 TCA will
be phased out.  Under the final NESHAP, existing sources must
comply 3 years after promulgation, which will be late 1997.
Therefore, TCA will be phased out before owners or operators
of solvent cleaning machines must comply with the NESHAP.
     Comment:  One commenter (IV-D-22) stated that for a
particular process in their operations, a large vapor
degreaser will need to be used until July 1997.  The commenter
estimated that under the proposed rule, it will take at least
$500,000 to bring the degreaser into compliance for only one
and a half years of use.  The commenter does not believe that
this cost will justify the potential environmental benefit.
     Response:  The commenter has not provided enough
information to allow the EPA to determine why the commenter
would achieve compliance with the rule at such a high cost.
However, as stated above, existing sources do not have to
comply with the final NESHAP until 3 years after promulgation;
which will be late 1997.
     Continent;  One commenter (IV-D-36) stated that emissions
averaging should be allowed as a means of demonstrating

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compliance with MACT standards.  Additionally, the commenter
proposed that the facility be allowed to show compliance with
an individual NESHAP by allowing emissions averaging within a
MACT standard or between and among the various MACT standards
applicable to the facility.
     Response;  The commenter (IV-D-36) has not provided any
examples of how incorporating emissions averaging into this
rule would be beneficial to the environment.  Therefore, the
EPA has not incorporated emissions averaging into this rule.
2.11.3  Organization
     Comment;  One commenter (IV-D-42) stated that the NESHAP
should be simplified and reorganized to make it more
understandable to the wide varieties of industries and
regulatory personnel affected.  As an example, the commenter
recommended one table showing requirements for all cleaners
including batch cold cleaners.
     Response;  The EPA is preparing a guidance document that
will explain in more detail the compliance options and their
requirements.  This will include a table showing the
requirements for all cleaning machines.  This guidance
document is scheduled to be published early in the year in
1995.
     Comment;  Several commenters  (IV-D-20; IV-D-29; IV-D-30;
IV-D-35; IV-D-42) recommended that the EPA emphasize the
standard for cold solvent cleaners by using a separate section
or a table.  Two commenters  (IV-D-20; IV-D-29) stated that
moving this small section to the front of the standards
section would provide more emphasis.
     Response;  The EPA has created a separate section for
batch cold cleaning machines in the final rule.
     Comment;  Two commenters  (IV-D-20; IV-D-29) suggested
that the test methods and monitoring procedures in § 63.465(a)
of the proposed rule be simplified by removing the words "used
to comply with these standards."
     Response;  The EPA believes that these words need to be
maintained in the final rule for clarification purposes.

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Therefore, § 63.465(a), subsections 1 through 4 have not been
modified as recommended by the commenter.
2.11.4  Other
     Preamble
     Comment;  One commenter (IV-D-33) stated that the
preamble was not sufficiently detailed to determine the basis
for EPA's regulatory approach.  The commenter cited the
following specific examples of where more detail is required
in the preamble:
     (1)  Information on how the MACT floor was derived;
     (2)  Whether the standard is based on the floor or values
above the floor;
     (3)  The basis for calculating the control combinations,
and whether these combinations are equivalent; and
     (4)  The model parameters used to simulate different
machine sizes, and the calculation of the MACT emission
limits.
     Response;  Detailed descriptions of these analyses are
contained in supporting documents that are available in Air
Docket number A-92-39.
     Solvent Workgroup
     Comments:  Two commenters (IV-D-31; IV-D-40) stated that
the EPA should seek industry input into the solvent
workgroup's deliberations.  One commenter (IV-D-40)
volunteered to participate.
     Response;  The EPA does not have provisions for industry
to serve on internal EPA workgroups.  However, the Agency has
contacted the commenters to inform them of an industry
symposium on solvent cleaning where their input could be used.
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TECHNICAL REPORT DATA
(Please read Instructions on reverse before completing)
1 . REPORT NO
EPA-453/R-94-071
-i
4 TITLE AND SUBTITLE
National Emission Standards for Hazardous Air Pollutants:
Halogenated Solvent Cleaning - Background Information for Final
Standards; Summary of Public Comments and Responses
7. AUTHOR(S)
Paul A. Almodovar
9 PERFORMING ORGANIZATION NAME AND ADDRESS
U.S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Research Triangle Park, NC 27711
12 SPONSORING AGENCY NAME AND ADDRESS
Director
Office of Air Quality Planning and Standards
Office of Air and Radiation
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
3. RECIPIENT'S ACCESSION NO
5 REPORT DATE
1994
6. PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATION REPORT NO.
10. PROGRAM ELEMENT NO
1 1 . CONTRACT/GRANT NO
13. TYPE OF REPORT AND
14 SPONSORING AGENCY'
EPA/200/04
PERIOD COVERED
CODE
15 SUPPLEMENTARY NOTES
EPA Project Manager: Paul A. Almodovar (919) 541-0283
16. ABSTRACT
This document includes a summary of all public comments that were submitted on the proposed rule,
along with responses to these comments. This summary of comments and responses serves as the basis
for the revisions made to the standards between proposal and promulgation. This document
complements the National Emission Standards for Hazardous Air Pollutants: Halogenated Solvent
Cleaning -Background Information Document (EPA-453/R-93-054, November 1993).
17.
a DESCRIPTORS
Halogenated Solvent Cleaning
Batch vapor cleaners
Batch cold cleaners
In-line cleaners
Hazardous Air Pollutants
National Emission Standards
Solvent Cleaning
18 DISTRIBUTION STATEMENT
Release Unlimited
KEY WORDS AND DOCUMENT ANALYSIS
b. IDENTIFIERS/OPEN ENDED TERMS
Air Pollution control
19. SECURITY CLASS (Report)
Unclassified
20. SECURITY CLASS (Page)
Unclassified

c. COSATI Field/Group

21. NO OF PAGES
165
22 PRICE
EPA Form 2220-1 (Rev. 4-77)   PREVIOUS EDITION IS OBSOLETE

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