[Federal Register: January 25, 1995 (Volume 60, Number 16)]
[Rules and Regulations ]
[Page 4947-4993]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr25ja95-9]

[[Page 4947]]

_______________________________________________________________________

Part II

Environmental Protection Agency

_______________________________________________________________________

40 CFR Parts 9 and 63

National Emission Standards for Chromium Emissions From Hard and
Decorative Chromium Electroplating and Chromium Anodizing Tanks; Final
Rule

[[Page 4948]]

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 9 and 63

[AD-FRL-5115-7]
RIN 2060-AC14


National Emission Standards for Chromium Emissions From Hard and
Decorative Chromium Electroplating and Chromium Anodizing Tanks

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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

SUMMARY: Pursuant to section 112 of the Clean Air Act as amended in
1990 (the Act), this action promulgates final standards that limit the
discharge of chromium compound air emissions from existing and new hard
chromium electroplating, decorative chromium electroplating, and
chromium anodizing tanks at major and area sources. Chromium compounds
are among the 189 hazardous air pollutants (HAP) listed for regulation
under section 112 of the Act. Hard and decorative chromium
electroplating and chromium anodizing tanks have been identified by the
EPA as significant emitters of chromium compounds to the atmosphere.
The purpose of the final rule is to reduce chromium compound air
emissions from the source categories identified above. All affected
sources must limit emissions to the level of the maximum achievable
control technology (MACT). The EPA is also finalizing Methods 306,
306A, and 306B with these standards.

DATES: Effective Date: January 25, 1995.
    Incorporation by Reference. The incorporation by reference of
certain publications in this standard is approved by the Director of
the Office of the Federal Register as of January 25, 1995.
    Judicial Review. Under section 307(b)(1) of the Act, judicial
review of national emission standards for hazardous air pollutants
(NESHAP) is available only by filing a petition for review in the U.S.
Court of Appeals for the District of Columbia Circuit within 60 days of
today's publication of this final rule. Under section 307(b)(2) of the
Act, the requirements that are the subject of today's notice may not be
challenged later in civil or criminal proceedings brought by the EPA to
enforce these requirements.

ADDRESSES: Docket. Docket No. A-88-02, containing information
considered by the EPA in developing the promulgated NESHAP for hard and
decorative chromium electroplating and chromium anodizing tanks is
available for public inspection and copying between 8 a.m. and 5:30
p.m., Monday through Friday, except for Federal holidays, at the EPA's
Air and Radiation Docket and Information Center, Room M1500, U. S.
Environmental Protection Agency, 401 M Street, SW., Washington, DC
20460; telephone (202) 260-7548. A reasonable fee may be charged for
copying.
    Background Information Document. A background information document
(BID) for the promulgated NESHAP may be obtained from the docket; the
U. S. EPA Library (MD-35), Research Triangle Park, North Carolina
27711, telephone (919) 541-2777; or from National Technical Information
Services, 5285 Port Royal Road, Springfield, Virginia 22161, telephone
(703) 487-4650. Please refer to ``Chromium Emissions from Chromium
Electroplating and Chromic Acid Anodizing Operations--Background
Information for Promulgated Standards'' (EPA-453/R-94-082b). The BID
contains a summary of the public comments made on the proposed
standards and EPA responses to the comments.

FOR FURTHER INFORMATION CONTACT: Mr. Lalit Banker of the Emission
Standards Division (MD-13), U. S. Environmental Protection Agency,
Research Triangle Park, North Carolina 27711; telephone (919) 541-5420.

SUPPLEMENTARY INFORMATION: The information presented in this preamble
is organized as follows:

I. Background
II. Summary
    A. Summary of Promulgated Standards
    B. Summary of Major Changes Since Proposal
III. Summary of Environmental, Energy, Cost, and Economic Impacts
    A. Environmental and Energy Impacts
    B. Cost Impacts
    C. Economic Impacts
IV. Public Participation
V. Significant Comments and Responses
    A. Selection of Source Categories and Pollutants to be Regulated
    B. Selection of MACT/GACT Approach
    C. Selection of MACT for Hard Chromium Electroplating Tanks
    D. Selection of MACT for Decorative Chromium Electroplating and
Chromium Anodizing Tanks
    E. Selection of the Format of the Standard
    F. Selection of the Emission Limits
    G. Selection of Compliance Dates
    H. Selection of Monitoring Requirements
    I. Selection of Test Methods
    J. Selection of Reporting and Recordkeeping Requirements
    K. Operating Permit Program
VI. Administrative Requirements
    A. Docket
    B. Executive Order 12866
    C. Paperwork Reduction Act
    D. Regulatory Flexibility Act
    E. Miscellaneous

I. Background

    Section 112(b) of the Act lists 189 HAP and requires the EPA to
establish national emission standards for all major sources and some
area sources of those HAP. Among the listed pollutants are chromium
compounds. On July 16, 1992 (57 FR 31576), the EPA published a list of
major and area sources for which NESHAP are to be promulgated and on
December 3, 1993 (58 FR 83941), the EPA published a schedule for
promulgation of those standards. The hard and decorative chromium
electroplating and chromium anodizing source categories are included in
the list of major and area sources for which the EPA is to establish
national emission standards by November 1994.
    This NESHAP was proposed in the Federal Register on December 16,
1993 (58 FR 65768). A public hearing on this rule was conducted on
January 20, 1994. In addition, 62 letters commenting on the proposed
rule were received during the public comment period, and 3 late
comments were received.

II. Summary

A. Summary of Promulgated Standards

    The final rule applies to major and area sources performing hard
chromium electroplating, decorative chromium electroplating, and
chromium anodizing. The affected source is each chromium electroplating
or chromium anodizing tank. The emission limitations for each of these
source categories are summarized in Table 1. These emission limitations
apply only during tank operation, including periods of startup and
shutdown. The emission limitation for all new hard chromium
electroplating tanks, and for existing hard chromium electroplating
tanks that are located at large, hard chromium electroplating
facilities is based on the use of a composite mesh-pad system. The
emission limitation for existing hard chromium electroplating tanks
located at small, hard chromium electroplating facilities is based on
the use of a packed-bed scrubber. For all existing and new sources
performing decorative chromium electroplating and all existing and new
sources performing chromium anodizing, the standard is based on the use
of fume suppressants. Even though these technologies formed the bases
for the standards, any technology can be used as long as it is
demonstrated to meet the prescribed emission limitation. All area and
major sources must limit emissions to the level of the maximum
achievable control technology (MACT).


[[Page 4949]]
                               Table 1.--Standards for Chromium Electroplating and Chromium Anodizing Tanks Based on MACT
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                 Emission limitations
        Type of tank         ---------------------------------------------------------------------------------------------------------------------------
                                                          Small                                                         Large
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                               Hard Chromium Plating Tanks
--------------------------------------------------------------------------------------------------------------------------------------------------------
All existing tanks..........  0.03 mg/dcsm (1.3 x 10<SUP>-5 gr/dscf)...........................  0.015 mg/dscm (6.6 x 10<SUP>-6 gr/dscf)
All new tanks...............  0.015 mg/dcsm (6.6 x 10<SUP>-6 gr/dscf)..........................  0.015 mg/dscm (6.6 x 10<SUP>-6 gr/dscf)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                               Decorative Chromium Plating Tanks Using a Chromic Acid Bath

--------------------------------------------------------------------------------------------------------------------------------------------------------
All new and existing tanks..
(1) 0.01 mg/dscm<SUP>a(4.4 x 10<SUP>-6
 gr/dscf)

--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Chromium Anodizing Tanks

--------------------------------------------------------------------------------------------------------------------------------------------------------
All new and existing tanks..
(1) 0.01 mg/dscm<SUP>a(4.4 x 10<SUP>-6
 gr/dscf)
--------------------------------------------------------------------------------------------------------------------------------------------------------
<SUP>aIn accordance with Sec. 63.342(d)(2), owners or operators using a fume suppressant containing a wetting agent as a control technique can meet an
  alternate emission limitation of 45 dynes/cm (3.1 x 10<SUP>-3 lb<INF>f/ft).

    Owners and operators of all affected sources are also subject to
work practice standards, which require them to complete an operation
and maintenance (O&M) plan that contains the minimum elements of
Sec. 63.342(f)(3) and Table 2.

              Table 2.--Summary of Work Practice Standards
------------------------------------------------------------------------
  Control technique      Work practice standards         Frequency
------------------------------------------------------------------------
Composite mesh-pad     1. Visually inspect device  1. 1/quarter.
 (CMP) system.          to ensure there is proper
                        drainage, no chromic acid
                        buildup on the pads, and
                        no evidence of chemical
                        attack on the structural
                        integrity of the device.
                       2. Visually inspect back    2. 1/quarter.
                        portion of the mesh pad
                        closet to the fan to
                        ensure there is no
                        breakthrough of chromic
                        acid mist.
                       3. Visually inspect         3. 1/quarter.
                        ductwork from tank or
                        tanks to the control
                        device to ensure there
                        are no leaks.
                       4. Perform washdown of the  4. Per manufacturer.
                        composite mesh-pads in
                        accordance with
                        manufacturers
                        recommendations.
Packed-bed scrubber    1. Visually inspect device  1. 1/quarter.
 (PBS).                 to ensure there is proper
                        drainage, no chromic acid
                        buildup on the packed
                        beds, and no evidence of
                        chemical attack on the
                        structural integrity of
                        the device.
                       2. Visually inspect back    2. 1/quarter.
                        portion of the chevron
                        blade mist eliminator to
                        ensure that it is dry and
                        there is no breakthrough
                        of chromic acid mist.
                       3. Same as number 3 above.  3. 1/quarter.
                       4. Add fresh makeup water   4. Whenever makeup is
                        to the top of the packed    added.
                        bed<SUP>a,b.
PBS/CMP system.......  1. Same as for CMP system.  1. 1/quarter.
                       2. Same as for CMP system.  2. 1/quarter.
                       3. Same as for CMP system.  3. 1/quarter.
                       4. Same as for CMP system.  4. Per manufacturer.
Fiber-bed mist         1. Visually inspect fiber-  1. 1/quarter.
 eliminator<SUP>c.           bed unit and prefiltering
                        device to ensure there is
                        proper drainage, no
                        chromic acid buildup in
                        the units, and no
                        evidence of chemical
                        attack on the structural
                        integrity of the devices.
                       2. Visually inspect         2. 1/quarter.
                        ductwork from tank or
                        tanks to the control
                        device to ensure there
                        are no leaks.
                       3. Perform washdown of      3. Per manufacturer.
                        fiber elements in
                        accordance with
                        manufacturers
                        recommendations.
Air pollution control  To be proposed by the       To be proposed by the
 device (APCD) not      source for approval by      source for approval
 listed in rule.        the Administrator.          by the
                                                    Administrator.

------------------------------------------------------------------------
                          Monitoring Equipment

------------------------------------------------------------------------
Pitot tube...........  Backflush with water, or    1/quarter.
                        remove from the duct and
                        rinse with fresh water.
                        Replace in the duct and
                        rotate 180 degrees to
                        ensure that the same zero
                        reading is obtained.
                        Check pitot tube ends for
                        damage. Replace pitot
                        tube if cracked or
                        fatigued.
Stalagmometer........  Follow manufacturers
                        recommendations.
------------------------------------------------------------------------
<SUP>aIf greater than 50 percent of the scrubber water is drained (e.g., for
  maintenance purposes), makeup water may be added to the scrubber
  basin.
<SUP>bFor horizontal-flow scrubbers, top is defined as the section of the
  unit directly above the packing media such that the makeup water would
  flow perpendicular to the air flow through the packing. For vertical-
  flow units, the top is defined as the area downstream of the packing
  material such that the makeup water would flow countercurrent to the
  air flow through the unit.
<SUP>cWork practice standards for the control device installed upstream of
  the fiber-bed mist eliminator to prevent plugging do not apply as long
  as the work practice standards for the fiber-bed unit are followed.

[[Page 4950]]

    All existing sources performing hard chromium electroplating and
chromium anodizing must comply with the emission limitations within 2
years of January 25, 1995. All existing sources performing decorative
chromium electroplating must comply with the emission limitations
within 1 year of January 25, 1995. All new and reconstructed sources
must comply immediately upon startup.
    Sources must demonstrate initial compliance with the prescribed
emission limitation in accordance with Secs. 63.343(b) and 63.344.
Continuous compliance is demonstrated through the monitoring required
by Sec. 64.343(c), as summarized in Table 3. As indicated in this
table, the type of compliance monitoring performed is based on the type
of control technique used to comply with the emission limitation, not
the type of source being controlled.

                                  Table 3.--Summary of Monitoring Requirements
----------------------------------------------------------------------------------------------------------------
                                                        Parameter(s) for compliance     Frequency of compliance
    Control technique       Initial compliance test             monitoring                    monitoring
----------------------------------------------------------------------------------------------------------------
Composite mesh-pad (CMP)   Yes......................  Pressure drop across the unit.  1/day.
 system.
Packed-bed scrubber (PSB)  Yes......................  Velocity pressure at the inlet  1/day.
                                                       of the control system and
                                                       pressure drop across the unit.
PBS/CMP system...........  Yes......................  Pressure drop across the unit.  1/day
Fiber-bed mist eliminator  Yes......................  Pressure drop across the fiber- 1/day.
                                                       bed mist eliminator and the
                                                       pressure drop across the
                                                       upstream control device used
                                                       to prevent plugging.
Wetting agent-type fume    Yes (Unless the criteria   Surface tension...............  Once every 4 hours.<SUP>a
 suppressant.               of Sec. 63.343(b)(2) are
                            met).
Foam blankets............  Yes......................  Foam thickness................  Once per hour.<SUP>a
Air pollution control      Yes......................  To be proposed by the source    N/A.
 device (APCD) not listed                              for approval by Administrator.
 in rule.
----------------------------------------------------------------------------------------------------------------
<SUP>aFrequency can be decreased according to Sec. 63.343 (c)(5)(ii) and (c)(6)(ii) of subpart N.

    Owners or operators of affected sources are required to keep the
records required by Sec. 63.346 to document compliance with these
standards. Records include those associated with the work practice
standards, performance test results, compliance monitoring data,
duration of exceedances, and records to support a Federally-enforceable
limit on facility size. Reports must also be periodically submitted.
Table 4 summarizes the reports to be submitted and the reporting
timeframes.

               Table 4.--Summary of Reporting Requirements
------------------------------------------------------------------------
 Section in Subpart N         Description        Timeframe for submittal
------------------------------------------------------------------------
Sec. 63.345(b).......  Notification of           Depends on when source
                        construction or           was constructed--see
                        reconstruction.           Sec. 63.345(b)(5).
Sec. 63.347(c)(1)....  Initial notification....  180 days after the
                                                  effective date.
Sec. 63.347(c)(2)....  --Notification of when    --Within 30 days of
                        construction commenced.   commencement for
                                                  sources built after
                                                  effective date, or
                                                  with notification
                                                  required by Sec.
                                                  63.345(b) if built
                                                  prior to effective
                                                  date.
                       --Notification of actual  --Within 30 days of
                        startup.                  startup.
Sec. 63.347(d).......  Notification of           At least 60 days prior
                        performance test.         to test.
Sec. 63.347(e).......  Notification of           Within 90 days of
                        compliance status.        performance test (if a
                                                  test is conducted) or
                                                  within 30 days of
                                                  compliance date.
Sec. 63.347(f).......  Notification of           Within 90 days of
                        performance test          performance test.
                        results.
Sec. 63.347(g).......  Compliance status         2 times/yr, or 4 times/
                        reports for major         yr if exceedances
                        sources.                  occur or if requested
                                                  by Administrator.
Sec. 63.347(h).......  Compliance status         Complete once/yr and
                        reports for area          maintain on site, or 2
                        sources.                  times/yr if
                                                  exceedances occur or
                                                  if requested by
                                                  Administrator.
Sec. 63.347(i).......  --Initial notification    --Within 180 days of
                        for users of TVC baths.   effective date.
                       --Notification of         --Within 30 days of
                        compliance status for     compliance date.
                        users of TVC baths.
                       --Notification of         --Within 30 days of
                        process change.           process change.
------------------------------------------------------------------------

B. Summary of Major Changes Since Proposal

    In response to public comments received and additional analyses
performed by the EPA, the following changes have been made to the final
rule since proposal:
    1. The emission limits associated with the control technologies
that form the bases for the standards have been revised. The emission
limit based on the use of a composite mesh-pad system is 0.015
milligrams of total chromium per dry standard cubic meter (mg/dscm) of
exhaust air. The emission limit based on the use of a fume suppressant
is 0.01 mg/dscm. The emission limit based on the use of a packed-bed
scrubber is unchanged (0.03 mg/dscm).


[[Page 4951]]
                                  Table 3.--Summary of Monitoring Requirements
----------------------------------------------------------------------------------------------------------------
                                                       Parameter(s) for compliance     Frequency of compliance
    Control technique       Initial compliance test             monitoring                    monitoring
----------------------------------------------------------------------------------------------------------------
Composite mesh-pad (CMP)   Yes......................  Pressure drop across the unit  1/day.
 system.
Packed-bed scrubber (PBS)  Yes......................  Velocity pressure at the       1/day.
                                                       inlet of the control system
                                                       and pressure drop across the
                                                       unit.
PBS/CMP system...........  Yes......................  Pressure drop across the unit  1/day.
Fiber-bed mist eliminator  Yes......................  Pressure drop across the       1/day.
                                                       fiber-bed mist eliminator
                                                       and the pressure drop across
                                                       the upstream control device
                                                       used to prevent plugging.
Wetting agent-type fume    Yes (Unless the criteria   Surface tension..............  Once every 4 hours.<SUP>a
 suppressant.               of Sec. 63.343(b)(2) are
                            met).
Foam blankets............  Yes......................  Foam thickness...............  Once per hour.<SUP>a
Air pollution control      Yes......................  To be proposed by the source   N/A
 device (APCD) not listed                              for approval by
 in rule.                                              Administrator.
----------------------------------------------------------------------------------------------------------------
<SUP>aFrequency can be decreased according to Sec. 63.343 (c)(5)(ii) and (c)(6)(ii) of subpart N.

               Table 4.--Summary of Reporting Requirements
------------------------------------------------------------------------
Section in subpart
         N                Description          Timeframe for submittal
------------------------------------------------------------------------
Sec. 63.345(b)....  Notification of          Depends on when source was
                     construction or          constructed--see Sec.
                     reconstruction.          63.345(b)(5).
Sec. 63.347(c)(1).  Initial notification...  180 days after the
                                              effective date.
Sec. 63.347(c)(2).  --Notification of when   --Within 30 days of
                     construction commenced.  commencement for sources
                                              built after effective
                                              date, or with notification
                                              required by Sec. 63.345(b)
                                              if built prior to
                                              effective date.
                    --Notification of        --Within 30 days of
                     actual startup.          startup.
Sec. 63.347(d)....  Notification of          At least 60 days prior to
                     performance test.        test.
Sec. 63.347(e)....  Notification of          Within 90 days of
                     compliance status.       performance test (if a
                                              test is conducted) or
                                              within 30 days of
                                              compliance date.
Sec. 63.347(f)....  Notification of          Within 90 days of
                     performance test         performance test.
                     results.
Sec. 63.347(g)....  Compliance status        2 times/yr, or 4 times/yr
                     reports for major        if exceedances occur or if
                     sources.                 requested by
                                              Administrator.
Sec. 63.347(h)....  Compliance status        Complete once/yr and
                     reports for area         maintain on site, or 2
                     sources.                 times/yr if exceedances
                                              occur or if requested by
                                              Administrator.
Sec. 63.347(i)....  --Initial notification   --Within 180 days of
                     for users of TVC baths.  effective date.
                    --Notification of        --Within 30 days of
                     compliance status for    compliance date.
                     users of TVC baths.
                    --Notification of        --Within 30 days of process
                     process change.          change.
------------------------------------------------------------------------

    2. Owners or operators of decorative chromium electroplating tanks
using a trivalent chromium process that incorporates a wetting agent
are required only to submit the notifications required by
Sec. 63.347(i) with subsequent notifications required if the process is
changed or replaced.
    3. Existing sources performing hard chromium electroplating and
chromium anodizing must comply with the standard within 2 years after
January 25, 1995. Existing sources performing decorative chromium
electroplating must comply with the standard within 1 year after
January 25, 1995.
    4. The monitoring, reporting, and recordkeeping requirements for
affected sources have been reduced to the extent possible while still
allowing the EPA to determine the compliance status on a continuous
basis. Special consideration has been given to area sources.
    5. Table 1 of subpart N clarifies which sections of the General
Provisions apply to sources subject to subpart N and which sections do
not.
    The rationale for the above changes is discussed in detail in
section V of this preamble, which summarizes the major comments
received on the proposed rule and the EPA's response to these comments.
This section also discusses major comments that were received but that
did not result in changes to the final rule.

III. Summary of Environmental, Energy, Cost, and Economic Impacts

A. Environmental and Energy Impacts

    The environmental and energy impacts for the sources covered by
this rulemaking are unchanged from proposal because the bases of the
MACT standards have not changed.

B. Cost Impacts

    The annualized cost of control for the sources covered by this
rulemaking remain unchanged from proposal because the bases of the MACT
standards have not changed.
    The monitoring, reporting, and recordkeeping burden in the final
rule has decreased from the proposed requirements. Likewise, the costs
of monitoring, reporting, and recordkeeping have also decreased. The
on-going, annual cost of the final monitoring, reporting, and
recordkeeping is approximately 160,000 hours for hard chromium
electroplaters, 29,000 hours for decorative chromium electroplaters
using a trivalent chromium plating process, 260,000 hours for other
decorative chromium electroplaters, and 70,000 hours for chromium
anodizers. Nationwide annual costs for these source categories are $3.5
million for hard chromium electroplaters, $640,000 for decorative
chromium electroplaters using a trivalent chromium plating process,
$5.8 million for other decorative chromium electroplaters, and $1.6
million for chromium anodizers. These numbers [[Page 4952]] are reduced
from the nationwide annual costs associated with monitoring, reporting,
and recordkeeping in the proposed rule of $8.6 million for hard
chromium electroplaters, $1.6 million for decorative chromium
electroplaters using a trivalent chromium plating process, $14 million
for other decorative chromium electroplaters, and $3.8 million for
chromium anodizers.

C. Economic Impacts

    The economic impacts for the sources covered by this rulemaking are
unchanged from proposal because the basis of the MACT standards have
not changed.

IV. Public Participation

    Prior to proposal of the chromium electroplating and anodizing
rule, meetings of the National Air Pollution Control Techniques
Advisory Committee (NAPCTAC) were held on January 30 and November 19,
1991. These meetings were open to the public, and each attendee was
given an opportunity to comment on the draft rule.
    The proposed rule was published in the Federal Register on December
16, 1993 (58 FR 65768). The preamble to the proposal discussed the
availability of the proposal BID (Chromium Electroplating NESHAP--
Background Information for Proposed Standards (Volume I: EPA-453/R-93-
030a and Volume II: EPA-453/R-93-030b)), which describes in detail the
regulatory alternatives considered and the impacts associated with
those alternatives. Public comments were solicited at the time of
proposal, and copies of the proposal BID were made available to
interested parties.
    The public comment period officially ended on March 14, 1994. A
public hearing was held on January 20, 1994. In addition, 62 comment
letters were received during the public comment period; 3 late comments
were also received. The comments were carefully considered, and where
determined to be appropriate by the Administrator, changes were made in
the final rule.

V. Significant Comments and Responses

    Comments on the proposed rule were received from industry,
environmental groups, and State and local regulatory agencies. A
detailed discussion of these comments and responses can be found in the
promulgation BID (see ADDRESSES section). The summary of comments and
responses in the promulgation BID serves as the basis for the revisions
that have been made to the rule between proposal and promulgation.

A. Selection of Source Categories and Pollutants To Be Regulated

    Six commenters said that maximum cumulative potential rectifier
capacity was an inappropriate parameter for determining facility size.
Sources may have excess rectifier capacity to handle atypical
applications, for safety purposes, or for other reasons, but may
routinely operate at a significantly lower rectifier output. Several
commenters urged the EPA to consider alternatives to the maximum
potential rectifier capacity specified, such as actual annual ampere-
hour usage, raising the maximum potential ampere-hour limit for small
sources to 100 million amp-hr/yr, allowing sources to multiply the
maximum potential rectifier capacity by 0.75 to account for oversizing,
or allowing sources to accept Federally-enforceable limits on their
rectifier capacity that would allow them to be categorized as ``small''
facilities.
    Although the cutoff between small and large hard chromium
electroplating facilities has not been changed, the EPA has included
two provisions in the final rule to allow sources to use actual
rectifier capacity or to limit their potential rectifier capacity. The
first provision is available to facilities whose production records
show that the previous annual, actual rectifier capacity was less than
60 million amp-hr/yr. Under this provision, hard chromium
electroplating facilities may determine their size by using actual
cumulative rectifier capacity in lieu of the maximum potential capacity
if nonresettable, amp-hr meters are used on affected tanks. The final
rule (Sec. 63.346(b)(12) and Sec. 63.347(c)(1)(vi)) requires that
records of amp-hr usage be kept.
    The final rule also allows all sources performing hard chromium
electroplating to establish Federally-enforceable limits on their
rectifier capacity to allow facilities to comply with the standards for
small, hard chromium electroplating tanks, even if those facilities
have potential rectifier capacities that exceed the 60 million amp-hr/
yr cutoff. A Federally-enforceable limit is obtained through the title
V permit that is required by Sec. 63.340(e) of the final rule. Records
are required in accordance with Sec. 63.346(b)(12) and
Sec. 63.347(c)(1)(viii) to document that the Federally-enforceable
limit is being maintained.
    The final rule has also been clarified to state that only the
rectifiers associated with hard chromium electroplating should be used
to determine maximum cumulative potential rectifier capacity.
    Comments were received regarding other processes conducted by this
source category that were not identified in the process description.
One commenter pointed out a distinction among decorative chromium
electroplating processes: Black chromium and white chromium. The
commenter stated that black chromium electroplating is more like hard
chromium electroplating in terms of process parameters, and the
commenter recommended that black chromium electroplating be subject to
the same requirements as hard chromium electroplating processes. Other
commenters noted that the proposed rule did not cover a hard chromium
electroplating method that uses lower amperage and a longer
electroplating time (less amperage per square foot than decorative
electroplating process) such that emissions are lower.
    In the final rule, the definitions of hard chromium electroplating,
decorative chromium electroplating, and chromium anodizing have been
expanded, and are now expressed in terms of process parameters as well
as by function. Regardless of what name a facility has assigned to its
process, for the purposes of the regulation, the process will be
regulated according to its function, bath operating parameters, and
desired plating characteristics. Therefore, black decorative chromium
electroplaters would likely be subject to the standards for hard
chromium electroplaters based on plating characteristics. The EPA will
provide States with additional guidance on these types of applicability
issues in the enabling document.
    The commenters that use a low-amperage electroplating process were
concerned that such a process would not be allowed by the rule, even
though emissions from this process are low. Although the process does
differ from other hard chromium electroplating processes in that a
lower amperage is used, the rule does not preclude the use of this
process or any other technique to meet the applicable emission
limitation. The rule does require that the technique be demonstrated
through performance testing conducted in accordance with the test
methods and procedures identified in the final rule, and that
compliance monitoring be conducted to determine continuous compliance.

B. Selection of MACT/GACT Approach

    Ten commenters questioned the Agency's decision to regulate area
sources with MACT. A number of these commenters disagreed that the
chromium compound toxicity data alone was justification for regulating
[[Page 4953]] area sources as stringently as major sources. Other
commenters stated that the costs to area sources regulated with MACT
was unduly burdensome, particularly if those sources would be subject
to title V. Two commenters suggested that the EPA apply GACT standards
to small facilities to allow the Agency to focus its resources on
facilities posing the greatest impact, or establish a threshold below
which sources would be subject to GACT. Another commenter questioned
the EPA's decision to apply MACT to area sources on the grounds that
the Act does not intend a residual risk analysis for area sources. This
commenter noted that it was important to have separate standards for
area sources even if GACT was as stringent as MACT to preserve the
intent of section 112(d).
    In determining whether to apply MACT or GACT to the area sources in
this source category, the EPA considered the toxicity of chromium
compounds emitted from such sources and the availability of controls.
The EPA has concluded that MACT should be applied to all area sources
in all source categories. The basis for this decision is the toxicity
of chromium compounds. The potency of hexavalent chromium, which is
categorized as a Group A carcinogen, is well documented, and at least
three epidemiological studies have shown a strong association between
lung cancer and occupational exposures to mixtures of trivalent and
hexavalent chromium. Therefore, the Agency has concluded that all
chromium compounds emitted to the air should be considered toxic until
adequate data are available to determine otherwise.
    In selecting MACT over GACT for all area sources, the EPA also
evaluated the availability of control technologies and the cost of
compliance for area sources. The control technologies that form the
bases for MACT are widely available.
    Although Sec. 112(d)(5) of the Act does allow an alternative
standard for area sources, the EPA interprets this paragraph as
authorizing the Administrator to establish GACT standard for area
sources when the imposition of MACT is determined to be unreasonable.
For the source categories subject to subpart N, the Agency considers it
reasonable to apply MACT to area sources.

C. Selection of MACT for Hard Chromium Electroplating Tanks

1. Selection of the MACT Floor
    Four commenters suggested that the MACT floor for new hard chromium
electroplating tanks should be based on the use of a fiber-bed mist
eliminator (FBME) because this is the best technology in use.
    The EPA has gathered additional information since proposal in
response to public comments received. Based on this information, a
total of five facilities are known to be using FBME to control chromium
emissions from affected hard chromium electroplating and chromium
anodizing tanks. These five facilities represent different sizes of
hard chromium electroplating and chromium anodizing operations.
    Emission test data were obtained from four of the five facilities
using FBME (see Item No. IV-B-01 of Docket A-88-02). The emission test
data available from one facility were incomplete and could not be used
to assess the performance of fiber-bed units. The test results from the
other facilities were adequate to evaluate the performance of FBME.
However, after a thorough evaluation, it was determined that the
limited data are not sufficient to establish an emission limit which
must be met on a continuous long-term basis. In one case, the data were
inadequate because only a single traverse was made when two should have
been performed. In the other cases, the quantity of emissions captured
during sampling was too small to meet Agency guidelines on minimum
quantification levels. These data, therefore, must be treated as
qualitative rather than quantitative results and may not be used to
establish achievable emission limits. Based on this qualitative
assessment, it appears that FBME offer excellent control potential.
    In evaluating control technologies, the Agency also must consider
the sustainability of any performance level. The EPA is concerned with
the long-term performance of these systems because of the tendency of
the fiber beds to plug. In other contexts, most vendors of FBME systems
do not recommend their use as primary pollution control systems.
Rather, they recommend that coarse prefiltering be provided upstream of
the fiber beds to prevent plugging. The prefiltering devices range from
a series of mesh pads to a complete packed-bed scrubber unit. At
present, there are no long-term data available to assess any actual
deterioration or operational problems associated with FBME. Fiber-bed
mist eliminators to control chromium electroplating and anodizing tanks
have only recently been installed as a result of local air district
requirements; therefore, it is unlikely that any long-term data are
available.
    Because of the uncertainties in both the measured FBME performance
data and the potential long-term variability of the system performance,
the Administrator cannot at this time determine that a more stringent
emission limit could be achieved based on the application of FBME
technology for new hard chromium plating or chromium anodizing
operations. Therefore, the final MACT performance level of new hard
chromium electroplating and chromium anodizing tanks is unchanged from
the proposal. However, the limited data do suggest that FBME systems
can achieve the emission limits established for composite mesh-pad
systems and fume suppressants. Because this standard is a performance
standard, the use of a specific technology is not mandatory; therefore,
any system that meets or exceeds the required performance level may be
used.
    In order to facilitate the use of FBME to achieve compliance with
the standard, monitoring provisions have been included in the final
rule for use with FBME. (See discussion in section V.H.) The test
methods in the proposed rule are suitable for demonstrating compliance
with the standard regardless of the control technology employed.
2. Regulatory Alternatives Considered
    Eight commenters suggested that the EPA was too limiting in the
regulatory alternatives for hard chromium electroplating operations.
These commenters believed that the EPA should allow sources in this
subcategory to use fume suppressants to comply with the standard,
instead of locking sources into a control technology, such as packed-
bed scrubbers. Four of the commenters also proposed that the EPA allow
new and existing hard chromium electroplating operations the option of
meeting the same surface tension limit allowed for decorative chromium
electroplating operations that use a wetting agent-type fume
suppressant.
    The EPA has selected an emission limit format to provide sources
with the flexibility to choose the emission control strategy best
suited to their facility. The regulation only requires that any
strategy selected meet the emission limits set out in the rule. As
such, hard chromium electroplating sources can use fume suppressants to
achieve compliance with the standard, as long as initial compliance
testing demonstrates that the emission limit stipulated in the standard
is being achieved. As discussed later in this preamble, however, on-
going compliance monitoring is control-technique specific. As such, the
owner or operator of any source that uses a fume suppressant to comply
with an emission limitation shall monitor surface tension or foam
blanket [[Page 4954]] thickness, as appropriate, to demonstrate
continuous compliance.
3. Selection of MACT
    Several commenters remarked that the standard for existing hard
chromium electroplaters is inappropriate. Nine commenters stated that
the standard was too stringent for large, hard chromium electroplaters;
small, hard chromium electroplaters; or both. The arguments against
regulating existing hard chromium electroplaters as stringently as that
proposed were primarily that the costs associated with the standard
were unduly burdensome and did not justify the resulting environmental
benefit, and the emission concentration limits specified in the
proposed rule were not consistently achievable using the control
devices upon which the standards are based.
    Five commenters, on the other hand, indicated that the standard for
small, hard chromium electroplaters was too lenient. The arguments
presented by the commenters who supported a more stringent standard for
small, hard chromium electroplaters were that the residual risk
associated with emissions from these sources warranted more stringent
controls, the Agency's interpretation of the MACT floor was flawed
(i.e.; should be based on a straight average, not a median); and the
control efficiency for packed-bed scrubbers is overstated, as are the
cost impacts for a standard based on the use of composite mesh-pad
systems.
    In setting an emission standard, the Act directs the Administrator
to take into account costs, nonair quality health and environmental
impacts, and energy requirements. To fulfill this requirement for
existing hard chromium electroplating sources, the EPA evaluated the
cost, impact, and benefit of a standard based on the use of a packed-
bed scrubber as well as a standard based on the use of a composite
mesh-pad system. The Agency's estimate of the incremental cost
effectiveness of requiring all sources to meet a standard based on
composite mesh-pad systems compared to one based on packed-bed
scrubbers is approximately $3.7 million per Megagram of chromium
controlled ($/Mg) for large sources and $10.7 million/Mg for small
sources.
    Based on the EPA's economic analysis, a standard based on the use
of composite mesh-pad systems by all sources would not cause adverse
economic effects on large sources that currently use packed-bed
scrubbers. Due to economies of scale, the economic impacts on larger
facilities are consistently less than those on small facilities. As a
result, larger facilities will have a greater ability to pass on
control costs. Although these costs may seem high, the EPA believes the
toxicity of chromium justifies these costs. In consideration of the
potential adverse impacts to small sources, the final rule requires a
less stringent standard for small sources than large sources, which is
based on the use of packed-bed scrubbers rather than composite mesh-pad
systems. [See Chapter 5 of the New Technology Document (``Technical
Assessment of New Emission Control Technologies Used in the Hard
Chromium Electroplating Industry;'' EPA-453/R-93-031) for a detailed
discussion of EPA's economic analysis for these systems.]
    The EPA considers the emission limitation based on the use of
composite mesh-pad systems to be representative of and consistently
achievable with well-maintained units. No data were submitted to
support an alternate emission limitation. (For further discussion of
the emission limitations, see section V.F.)
    Regarding the comments that the proposed standard for small, hard
electroplaters was too lenient, the Agency believes that the MACT floor
is properly based on the use of packed-bed scrubbers for this source
category. The EPA promulgated a final rule on June 6, 1994 (57 FR
29196) that presents the Agency's interpretation of section 112(d)(A)
of the Act regarding the basis for the MACT floor. Under this
interpretation, the Agency considers the emission limitations achieved
by the best performing 12 percent of existing sources and arrives at
the MACT floor by selecting the median of the values, rather than a
straight average. This interpretation was followed in establishing the
MACT floor for small, hard chromium electroplaters. The Agency
considers any discussion of the risk remaining from small, hard
chromium electroplaters to be premature at this time.
    In accordance with section 112(f) of the Act, if a significant
residual risk from small, hard chromium electroplating operations
regulated by MACT is found, the Agency is required to promulgate
standards to mitigate that risk. The EPA recognizes the potential
hazards of chromium emissions from small sources and has chosen to
regulate area sources with MACT rather than GACT. The EPA also
considers its cost and impact analysis for small, hard chromium
electroplaters to be sound. The EPA estimated retrofit costs based on
information from vendors who supply the equipment to the industry, and
therefore estimates are representative of the control costs incurred by
affected sources. The EPA considers the efficiency assigned to packed-
bed scrubbers for purposes of calculating impacts to be representative
of that achieved by well-maintained and well-operated units controlling
emissions from hard chromium electroplating tanks. As with comments on
the emission limit based on composite mesh-pad systems, no data
supporting alternate emission limits for a standard based on packed-bed
scrubbers were submitted.

D. Selection of MACT for Decorative Chromium Electroplating and
Chromium Anodizing Tanks

1. Regulation of the Trivalent Chromium Plating Process
    Eleven commenters disagreed that decorative chromium electroplating
tanks that use a trivalent chromium process should be regulated by the
proposed rule. Many of the commenters felt that the EPA had
insufficient data to conclude that the risk associated with this
process warranted regulation of those sources. Four commenters found
fault with the EPA's supporting data and noted that the level of
hexavalent chromium in a trivalent chromium bath that corresponds to
the EPA's estimate of hexavalent emissions from that bath would far
exceed that level of hexavalent chromium that would destroy the
trivalent bath. Three other commenters stated that use of the trivalent
chromium process should be encouraged by the EPA, because trivalent
processes result in less total chromium in process wastewater and less
sludge generation. One of the commenters suggested regulating trivalent
chromium electroplating processes under GACT to eliminate some of the
burden associated with the reporting, recordkeeping, and monitoring
requirements specified in the proposed rule.
    Twelve commenters responded to the EPA's request for comment on
whether the trivalent chromium electroplating process should be
required for new sources. The majority of these commenters did not
think that this should be a requirement because the process was not
technically feasible for the full range of decorative chromium
electroplating operations. Two commenters pointed out inconsistencies
in the EPA's reasoning; the EPA can only require trivalent chromium
baths if it recognizes the difference in toxicity between hexavalent
and trivalent chromium.
    The EPA has reconsidered the technical basis for regulating tanks
[[Page 4955]] using the trivalent chromium electroplating process and
the feasibility of requiring such a process for new sources. During
development of the proposed standards, the EPA evaluated the trivalent
chromium electroplating process as a pollution prevention alternative.
Chromic acid is not present in the plating solution in the trivalent
chromium processes, and hexavalent chromium is regarded as a bath
contaminant in these processes. In addition, all of the trivalent
chromium plating solutions with which EPA is familiar contain a wetting
agent as an inherent bath component. That is, the wetting agent is part
of the plating solution purchased from the vendor; it is not added
separately by the end user.
    With a trivalent chromium plating process, the potential emissions
of chromium in any form are much lower because the concentration of
total chromium in trivalent chromium baths is approximately four times
lower than the total chromium concentration in chromic acid baths.
Trivalent chromium processes greatly reduce emissions of the most
potent form of chromium (hexavalent), and significantly lower emissions
of chromium in other forms. In addition to reduction of air emissions,
the use of trivalent chromium processes results in lower chromium
concentrations in process wastewaters and, consequently, reduces the
amount of sludge generated. Based on a source test conducted by the
EPA, total chromium emissions from a trivalent chromium bath are
approximately 99 percent less than those from a traditional,
uncontrolled decorative hexavalent chromium bath. Hexavalent chromium
emissions from a trivalent chromium bath were found to be approximately
equivalent to those emitted from a decorative hexavalent chromium bath
controlled by adding a wetting agent.
    Although chromium emissions from the trivalent chromium process
were low, the EPA had not anticipated the presence of hexavalent
chromium in emissions from the trivalent electroplating process nor the
level of total chromium emissions. Given that the Act lists all forms
of chromium on the HAP list, the EPA considered the trivalent chromium
electroplating process as a source of chromium emissions as well as an
emission control alternative for the chromic acid electroplating
process. Based on the emission test results, a decorative hexavalent
chromium bath controlled by adding a wetting agent had equivalent
hexavalent chromium emissions and less total chromium emissions than a
trivalent chromium plating bath. (As previously stated, for trivalent
chromium baths, the wetting agent is inherent to the solution; it does
not need to be added by the user.) In addition, the trivalent chromium
process may not be technically feasible for all decorative chromium
electroplating applications. Therefore, the final rule does not require
the use of a trivalent chromium electroplating process for either
existing or new decorative chromium electroplating tanks.
    The EPA has decided to regulate sources that use trivalent chromium
baths in the final rule. It is not clear whether the EPA data
accurately reflect emissions from the trivalent chromium electroplating
process, or if the analytical integrity of the data is suspect. In
light of the ambiguity of the air emissions data, and given the other
environmental benefits from the trivalent chromium process, the EPA has
decided to regulate these baths differently from hexavalent chromium
electroplating baths.
    The final rule requires users of trivalent chromium baths to submit
an initial notification and a notification of compliance status
certifying that a trivalent chromium bath is being used and identifying
the bath components (specifically, the wetting agent). Subsequent
notifications are required only if the process is changed, or if a new
trivalent chromium process is introduced. Users of trivalent chromium
baths must also keep records of bath chemicals purchased so the EPA can
be assured that the bath contains a wetting agent. These notification
and recordkeeping requirements apply only to those trivalent chromium
baths that incorporate a wetting agent. The EPA has evaluated baths
with this characteristic and found them to have the environmental
benefits discussed above. Although such baths are not known to exist,
the EPA has chosen to regulate trivalent chromium baths that do not
incorporate a wetting agent in the same manner as decorative chromium
baths using a chromic acid solution. The EPA believes that this will
discourage the use of a trivalent chromium bath that does not have a
wetting agent as an inherent bath component.
2. Selection of MACT for Decorative Chromium Electroplating Tanks
    Three commenters suggested that the proposed emission limit of
0.003 mg/dscm for decorative chromium electroplaters using hexavalent
chromium baths was too stringent. Two commenters did not think that a
source using either a fume suppressant or a fume suppressant in
conjunction with a packed-bed scrubber could consistently meet a limit
of 0.003 mg/dscm.
    In response to the comments received at proposal, the EPA has
reconsidered the basis for the emission limit of 0.003 mg/dscm for
decorative chromium electroplating and chromium anodizing tanks. As
stated in the preamble to the proposed rule, this emission limit was
based on tests of a decorative chromium electroplating tank in which a
combination wetting agent/foam blanket was used to control emissions.
Tests had also been conducted on a decorative chromium electroplating
tank using only a foam blanket for control. The chromium emission data
for all types of fume suppressants ranged from 0.001 to 0.007 mg/dscm,
with the wetting agent/foam blanket data ranging from 0.001 to 0.003
mg/dscm and the foam blanket data ranging from 0.003 to 0.007 mg/dscm.
In evaluating whether the proposed emission limit of 0.003 mg/dscm
should be revised in the final rule, the EPA reassessed the effect the
test methods may have had on the emission data obtained. The analytical
method used for the fume suppressant test was colorimetric
spectroscopy. As more efficient control technologies (such as composite
mesh-pad systems) were developed, a more sensitive analytical method
was needed to measure the lower concentrations of chromium being
emitted. Therefore, the more sensitive ion chromatography method was
used in the later phases of emission testing for these standards
involving add-on control devices.
    By using the less sensitive colorimetric analytical method, it is
unclear whether the variation found between the two types of fume
suppressants was due to a performance difference in the fume
suppressants or was an artifact of the analytical method used. The fact
that there is overlap between the foam blanket and wetting agent/foam
blanket data further indicates that this could be the case. (Both were
able to achieve a limit of 0.003 mg/dscm in one instance.) Therefore,
the EPA has concluded that the emission limit in the final rule should
be based on the performance of both foam blankets and wetting agents.
Accordingly, the emission limit selected for decorative chromium
electroplating and chromium anodizing tanks in the final rule is 0.01
mg/dscm. This emission limit was selected by applying a safety factor
to the highest measured data point (0.007 mg/dscm) to account for
variations in sampling and analytical procedures. The selection of this
emission limit is consistent with the methodology used to select
emission limits based on other control [[Page 4956]] techniques, as is
further discussed in section V.F.
3. Selection of MACT Floor/MACT for Chromium Anodizing Tanks
    Three commenters questioned the MACT floor established by the EPA
for sources performing chromium anodizing. The commenters stated that
it did not appear that the EPA had sufficient data to perform a MACT
floor analysis for these sources. Commenters stated that chromium
anodizers and decorative chromium electroplaters that cannot use fume
suppressants should be considered separately, and the MACT floor for
such sources should be based on packed-bed scrubbers. Also, according
to six commenters, the standard for chromium anodizing tanks is not
achievable in all situations, especially when an add-on control device
is used in lieu of fume suppressants. One commenter stated that unless
the standard for chromium anodizing tanks controlled with add-on
control devices is set at 0.03 mg/dscm, sources will have to use an
add-on control device followed by a fiber-bed mist eliminator to
achieve the emission limit.
    The MACT floor for chromium anodizing sources was based on
information available to the EPA on the source category. Information on
the industry was obtained through survey questionnaires to both
industry representatives and control system vendors, site visit
reports, and available emission data. Although information was not
available from all sources in the category, the EPA believes the
information was sufficient to satisfy the requirements of section
112(d)(3) of the Act. The survey responses, which included some
aerospace facilities, indicated that fume suppressants were the control
technique used predominantly in the industry. Section 112(d)(3) of the
Act prohibits the EPA from establishing a standard that is any less
stringent than the MACT floor for a category or subcategory of sources.
No technical reason was provided by industry, nor is one known to the
EPA, for creating a separate subcategory of sources for which fume
suppressants are not technically feasible. Thus, all new and existing
sources performing chromium anodizing must meet either an emission
limit of 0.01 mg/dscm or maintain the surface tension specified in the
rule. The EPA believes that the revised chromium emission limit of 0.01
mg/dscm for chromium anodizing tanks in the final rule is achievable by
sources using add-on control technology. Alternatively, the EPA
believes that the compliance timeframe for existing sources performing
chromium anodizing in the final rule (2 years) will allow these sources
to further investigate the feasibility of using fume suppressants.

E. Selection of the Format of the Standard

    Seven commenters stated that the format of the standard should be
expressed as a process emission rate in milligrams of chromium emitted
per amp-hour of operation (mg/amp-hr), which would be consistent with
California rules, rather than as an emission concentration (mg/dscm).
According to the commenters, concentration-based standards are flawed
because they can be circumvented by dilution, concentration can vary
from system to system, and source test data indicate that outlet
concentrations vary widely for different inlet conditions. Several
commenters also pointed out that emissions should be correlated to
production rates because chromium emissions increase proportionately
with increased current. Two other commenters suggested that the final
rule specify acceptable process emission rates to avoid an equivalency
evaluation.
    Based on the Agency's evaluation, the available test data indicate
that a process emission rate format will not ensure consistent
compliance with the control level required by the standard. The
concentration data collected by the EPA for the composite mesh-pad and
packed-bed scrubber systems do not overlap; that is, composite mesh-pad
systems consistently outperform packed-bed scrubbers. The process
emission rate data, on the other hand do overlap; even though composite
mesh-pad systems are a superior technology to packed-bed scrubbers,
both sometimes achieve the same process emission rate. This occurs
because two sources can be using the same control technology and
achieving the same outlet emissions concentration, but the one with the
higher current loading will have a lower process emission rate.
Commenters contend that this is reasonable because the production rate,
as measured in ampere-hours, is related to emissions. However, the
amount of current supplied to the tank is an indicator of the amount of
uncontrolled emissions from the tank, not the controlled emission level
from the tank. Because of the differences in process emission rate-
based and concentration-based standards, and the source-specific nature
of process emission rate standards, the EPA cannot cite an equivalent
process emission rate in the final rule.
    Regarding the issue of circumvention of the standard through
dilution of the emission stream, the EPA believes that dilution of the
gas stream can be determined by reviewing test and permit data for a
facility. The outlet air flow rate measured during testing should
approximate the design air flow rate for the control system reported on
the permit application. If the two values differ significantly, then an
inspection of the control system can be made to determine if dilution
air is being introduced. It is also possible for a facility to dilute
the inlet gas stream to the control device by designing a system to
ventilate the electroplating tanks at air flow rates substantially
above those required for adequate ventilation. However, the increased
installation and maintenance costs associated with such a system would
outweigh the costs of complying with the standard without dilution.
Further, Sec. 63.4(b) of the General Provisions expressly prohibits
dilution as a means to comply with an emission limit. Therefore,
concerns of dilution of the air stream were not considered to outweigh
the benefits of a concentration-based format for the standard.
    Eight commenters disagreed with the EPA's decision to base the
standard on emissions of total chromium rather than on emissions of
hexavalent chromium. Two commenters suggested allowing sources to
demonstrate compliance by testing for hexavalent chromium in lieu of
total chromium.
    The EPA decided to base the standard on total chromium because the
HAP list identifies all chromium compounds, not just hexavalent
chromium compounds. In addition, based on testing conducted by the EPA
for these source categories, the available test data indicate that
hexavalent and total chromium levels in the emission stream were
essentially the same for chromic acid baths (varying within
<plus-minus>10 percent in most instances). Because the EPA data base is
mainly comprised of data measured as hexavalent chromium, the final
rule does allow all sources using chromic acid baths to demonstrate
compliance by measuring either hexavalent or total chromium for all
sources.

F. Selection of the Emission Limits

    Many commenters stated that the emission limit based on the use of
composite mesh-pad systems should be changed. Three commenters
suggested lowering the emission limit that is based on the use of
composite mesh-pad systems, stating that the EPA did not test the best
systems available, and suggested levels ranging from 0.001 mg/dscm to
0.009 mg/dscm. Other [[Page 4957]] commenters stated that the proposed
limit based on composite mesh-pad systems (0.013 mg/dscm) was too low.
Five commenters stated that the proposed emission limit for packed-bed
scrubbers was also too high, noting that some units tested by the EPA
did not achieve this limit.
    The proposed emission limit of 0.013 mg/dscm for large hard
chromium electroplaters was based on tests that the EPA conducted on
actual control devices operating under normal process conditions. Lower
limits than the one selected for large sources were measured from these
devices, but the EPA based the emission limit on the highest measured
data point and believes that this limit is consistently achievable.
Regarding the emission limit based on packed-bed scrubbers, the EPA did
test some packed-bed scrubber systems that were not achieving the level
of 0.03 mg/dscm required by the proposed standard. However, these
devices were not optimized to achieve the higher removal efficiencies.
Specifically, when scrubbers were operated with periodic or continuous
washdown in which fresh water was supplied as makeup to the top of the
bed, a limit of at least 0.03 mg/dscm was achieved. The final rule
includes work practice standards that require the use of fresh water
added to the top of the packed bed whenever makeup additions occur.
Thus, packed-bed scrubbers that are operated in accordance with the
requirements of the rule should be able to achieve a limit of 0.03 mg/
dscm. The EPA does not think it is appropriate to substantially change
the emission limits based on the use of composite mesh-pad systems or
packed-bed scrubbers; the commenters did not provide data that
supported their claim that different emission limits are more
appropriate.
    As discussed previously, the emission limit for decorative chromium
electroplating tanks and chromium anodizing tanks has been changed to
0.01 mg/dscm in the final rule by applying a safety factor to the
highest data point (0.007 mg/dscm) in the fume suppressant data base.
Similarly, the emission limit that is based on packed-bed scrubbers is
based on rounding the highest value (0.028 mg/dscm) in the packed-bed
scrubber data base to 0.03 mg/dscm to incorporate a safety factor.
Therefore, in the final rule, the emission limit that is based on the
use of composite mesh-pad systems (0.013 mg/dscm) has been adjusted to
0.015 mg/dscm by applying a safety factor to the highest value (0.013
mg/dscm) in the data base to ensure that the limit is achievable on a
consistent basis.

G. Selection of Compliance Dates

    Several commenters stated that the proposed compliance dates for
affected existing sources did not allow sufficient time to achieve
compliance with the proposed rule. The majority of these commenters
suggested compliance timeframes of 2 to 3 years. According to the
commenters, the compliance period specified in the proposed rule did
not allow enough time to inform and educate affected owners and
operators; acquire capital; conduct research and test systems;
identify, purchase, and install control equipment; develop startup,
shutdown, and malfunction plans; train staff; build inventories; and
establish reporting and recordkeeping systems.
    The Agency agrees with the commenters that the compliance
timeframes for affected sources should be increased. The EPA recognizes
that some of the facilities within all of the source categories will
have to investigate the technical feasibility of installing control
devices or using other technologies at their facility to meet the
standards. Also, many area sources are not yet aware that a rule is to
be promulgated for their industry, and time is needed for them to be
made aware of the requirements of this rule. Therefore, the EPA has
extended the compliance date to 1 year after the promulgation date for
existing decorative chromium electroplaters and 2 years after the
promulgation date for existing hard chromium electroplaters and
chromium anodizers. The EPA believes that the 1 year timeframe for
decorative chromium electroplaters is sufficient because, based on the
EPA's survey data, 80 percent of existing sources already use fume
suppressants and very few will need to install add-on air pollution
control devices. The EPA thinks that the compliance timeframes in the
final rule will address commenters concerns and still ensure
implementation of controls in a timely fashion. Due to the toxicity of
chromium compounds and the importance of controlling chromium emissions
to protect human health and the environment, the Agency decided against
a compliance time longer than 2 years for any of the source categories
affected.
    To accommodate sources that cannot comply with the standard by the
compliance date, Sec. 63.6(i) of the General Provisions and
Sec. 63.343(a)(6) of subpart N allows a source to request a 1-year
compliance extension, which must be submitted 6 months in advance of
the compliance date identified in the regulation. This extension
combined with the compliance timeframes in the proposed rule could
provide a total of 2 years for compliance for decorative chromium
electroplaters and 3 years for compliance for hard chromium
electroplaters and chromium anodizers.

H. Selection of Monitoring Requirements

    Section 114(a)(3) of the Act requires enhanced monitoring and
compliance certification of all major stationary sources. The annual
compliance certifications certify whether compliance has been
continuous or intermittent. Enhanced monitoring shall be capable of
detecting deviations from each applicable emission limit or standard
with sufficient representativeness, accuracy, precision, reliability,
frequency, and timeliness to determine if compliance is continuous
during a reporting period. The monitoring in this regulation satisfies
the requirements of enhanced monitoring.
1. Compliance Monitoring for Add-on Air Pollution Control Devices
    Eleven comments addressed the suitability of measuring gas velocity
to demonstrate on-going compliance when add-on air pollution control
devices are used to comply with an emission limit. The commenters
stated that measuring gas velocity is very complicated, redundant with
measuring pressure drop, and not indicative of control device
performance. Two commenters pointed out that no suitable testing point
may be accessible, and a permanent measurement device may be fouled by
chromic acid.
    Several commenters remarked on the requirement for measuring
chromium concentration in the scrubber water. Four of these commenters
stated that there is no obvious relationship between scrubber water
chromium concentration and scrubber performance. Other commenters
indicated that measurement of chromium concentration in scrubber water
with a hydrometer is not accurate.
    In revising the proposed rule, the EPA recognizes that the
measurement of gas velocity could be burdensome and that other control
system parameters could potentially be used to determine on-going
compliance. Therefore, in the final rule, sources using composite mesh-
pad systems are required to monitor pressure drop across the device for
compliance purposes. Based on information gathered by the EPA, pressure
drop is directly related to composite mesh-pad system performance,
measurement of pressure drop is straightforward, and some users of
composite mesh-pad systems are currently monitoring pressure drop. The
[[Page 4958]] EPA believes that this change makes the rule more
flexible for regulated sources, while still ensuring that the EPA has a
mechanism for determining compliance with the emission limits at any
given time.
    The final rule requires sources that use a packed-bed scrubber to
meet the emission limit must measure the velocity pressure at the inlet
to the control system as well as the pressure drop across the device.
The relationship between pressure drop and packed-bed scrubber
performance is less reliable than the relationship between pressure
drop and composite mesh-pad system performance because of the lower
pressure drop in packed-bed scrubbers. Therefore, the EPA also requires
sources using packed-bed scrubbers to monitor the velocity pressure at
the inlet to the control device. This requirement will ensure that the
gas velocity through the control system is maintained in accordance
with vendor recommendations and, along with the pressure drop
monitoring, will ensure that the control system is properly operating.
    The requirement that sources using packed-bed scrubbers monitor the
chromium concentration in the scrubber water has been eliminated,
because the EPA concluded that monitoring of the velocity pressure at
the control device inlet and the pressure drop across the device was
sufficient to demonstrate compliance with the emission limits when
packed-bed scrubbers are used.
    Compliance monitoring requirements for fiber-bed mist eliminators
have been added in the final rule because these devices could likely be
used to meet the emission limitations, and some fiber-bed mist
eliminators are known to be in use. Sources that use a fiber-bed mist
eliminator to meet the emission limit must measure the pressure drop
across the fiber-bed unit, as well as the pressure drop across the
control device upstream of the fiber-bed unit that is in place to
prevent plugging.
    As discussed above, several changes have been made to the
monitoring requirements specified in the proposed rule based on the
EPA's review of comments received on the proposed rule and further
investigation of which process parameters relate best to proper
performance of the control systems. The final compliance monitoring
requirements are found in Sec. 63.343(c) of the final rule.
2. Work Practice Standards for Add-on Air Pollution Control Devices
    In the proposed rule, Operation and Maintenance (O&M) requirements
for add-on air pollution control devices consisted of adding makeup
water to packed-bed scrubbers, requiring washdown of composite mesh
pads, and various inspections for both types of control devices. The
majority of comments focused on the requirements associated with makeup
water for packed beds and washdown for composite mesh pads. Several
commenters suggested alternatives for the requirements for adding
makeup water to packed-bed scrubbers. The commenters disagreed that
makeup water can or should be added to the top of the scrubber. Others
questioned the need to use fresh water in scrubbers and composite mesh
pads because doing so increased wastewater flows. Other commenters
requested that the final rule define the term ``fresh water.''
    In the final rule, the O&M requirements have been replaced with
work practice standards that address O&M practices [Sec. 63.342(f)].
The final rule continues to require sources using packed-bed scrubbers
to meet an emission limit and ensure that all makeup water is fresh and
supplied to the unit at the top of the packed bed. The EPA considers
this requirement essential to meeting the prescribed emission limit.
During source testing conducted by the EPA to establish the performance
level of packed-bed scrubbers, it was noted that a system equipped with
an overhead spray system that periodically cleaned the packing with
fresh water performed much better than a system without such cleaning.
Based on those results, the EPA believes that without the requirement
that makeup water be fresh and added to the top of the packed bed,
scrubbers will not continuously meet the required emission limit even
if the scrubber met the limit during the initial performance test and
is operated within the appropriate ranges of pressure drop and velocity
pressure. For clarification, the term fresh water is defined in the
final rule.
    There were 11 comments on the washdown requirements for composite
mesh-pad systems. Several of these commenters indicated that the
specified washdown frequency was either impractical, infeasible, or
unnecessary. Seven commenters suggested washdown requirements for
composite mesh-pad systems be site-specific, as recommended by vendors,
or apply only if pressure drop determinations indicate the potential
presence of chromic acid buildup. Two commenters indicated that the
washdown water will likely exceed the quantity of water that can be
recycled, thus resulting in a wastewater stream that needs to be
treated.
    In the final rule, the EPA has revised the requirement that sources
complying with an emission limit by using a composite mesh-pad system
perform washdown of the pads. The EPA believes that washdown is an
essential part of composite mesh-pad system operation; if proper system
maintenance such as washdown does not occur, there will be a decline in
system performance. However, instead of specifying a washdown
frequency, the revised rule specifies that washdown be conducted in
accordance with manufacturers' recommendations as part of a facility's
O&M plan. The EPA recognizes that vendor designs for these systems vary
significantly, and the requirements for washdown are based on the
design of the unit and the operation of the plating tanks. The
frequency of washdown is dependent upon the position of the pad in the
control unit. Pads located in the front portions of the unit are
exposed to higher chromium concentrations and, therefore, require
washdowns more frequently than those located in the back of the unit.
Washdown practices recommended by manufacturers vary from continuous in
some cases to a maximum of once every 1 to 2 weeks.
    The EPA has also added work practice standards for fiber-bed mist
eliminators in the final rule because these control devices are likely
to meet the emission limitations, and are known to be in use by sources
affected by these standards. The work practice standards identified for
fiber-bed mist eliminators are analogous to those identified for the
composite mesh-pad system. Washdown requirements for fiber-bed units
will depend on the efficiency of the prefiltering device and the
operation of the plating tanks. Fiber-bed units installed downstream of
more efficient prefiltering systems, such as packed-bed scrubbers, will
require less frequent washdown than those using a less effective
prefiltering device because of the lower inlet loading to the unit.
Most vendors of fiber-bed units recommended monitoring of the pressure
drop as a means of gauging when the unit needs to be washed down. If an
increase in pressure drop is observed, then the unit will be washed
down to remove any chromium built up on the fiber elements.
3. Frequency of Monitoring for Add-on Air Pollution Control Devices
    Fourteen commenters indicated that the daily monitoring of add-on
air pollution control devices is unnecessary, particularly for small
sources, and suggested that at least some of the monitoring be required
on only a weekly, monthly, or quarterly basis. [[Page 4959]] Other
commenters suggested that monitoring be tied to production rate, that
monitoring be conducted only on days when electroplating is taking
place, or that monitoring requirements be reduced after the source has
been in compliance for 6 months. Commenters also requested that
monitoring be required only during tank operation, and that tank
operation be defined. Several commenters disagreed with the proposed
inspection frequency because of increased exposure hazards to persons
conducting the inspections or of anticipated down-time due to the
inaccessibility of control systems.
    In response to these comments and to minimize the burden on
regulated sources, the EPA has reduced the burden associated with the
compliance monitoring and work practice standards in the final rule.
The final rule continues to require daily monitoring of pressure drop
and velocity pressure for compliance, but the monitoring procedures
specified in the rule are the minimum required to determine continuous
compliance. Once the monitoring devices are in place, the only labor
required is that needed to read the gauges. The frequency of
inspections for compliance with the work practice standards has also
been reduced or revised. In the final rule, the frequency of
inspections has been reduced from monthly or daily to once every 3
months. The EPA believes that the inspections are still necessary to
ensure that system degradation is not occurring over time, because
gradual degradation may not be apparent from compliance monitoring
alone. Some commenters noted that their systems were not accessible for
inspection, or that the inspection would result in extended downtime.
The compliance timeframes in the final rule should allow sources
sufficient time to retrofit their systems to facilitate inspections,
and the negative effects of any downtime are minimized by the reduced
inspection frequency.
    The final rule also has been clarified so that monitoring
requirements apply only during tank operation; tank operation is
defined in Sec. 63.341.
4. Compliance Monitoring Associated With Fume Suppressants
    Regarding the use of wetting agent-type fume suppressants, seven
commenters indicated that the requirement for maintaining surface
tension below 40 dynes/cm for chromic acid baths is inappropriate. The
reasons provided by the commenters were that a surface tension standard
may not be prudent to demonstrate compliance, a direct correlation
between exceedance of parameters and emission limits has not been
established, and the rule should allow sources to set their own
compliance value for surface tension. Other commenters noted that the
specified limit was either too low or was not consistent with
manufacturers' recommendations.
    Based on data collected by the EPA, the performance of an
electroplating bath controlled with a wetting agent-type fume
suppressant can be determined by the surface tension of the bath.
Therefore, the EPA believes that there is a direct link between surface
tension and emissions. The EPA also believes that it is necessary and
appropriate to set a default value for surface tension in the rule.
Based on the EPA's experience, many decorative chromium electroplating
tanks are not ventilated, making source testing impossible without
considerable retrofitting.
    The EPA has increased the default surface tension limit from the
proposed 40 dynes/cm to 45 dynes/cm based on information received
during the comment period. However, if a facility believes that a
different surface tension value is appropriate, the rule allows a
source to conduct a performance test concurrently with surface tension
monitoring to establish the maximum surface tension that corresponds to
compliance with the emission limits. The source would subsequently
monitor surface tension, with an exceedance occurring if the surface
tension of the bath exceeded the value measured during the performance
test.
    Regarding foam blanket-type fume suppressants, several commenters
were concerned about the technique for measuring foam blanket thickness
and the potential hazards associated with this measurement. Another
commenter stated that the stack testing requirement is unreasonable due
to its excessive cost.
    The EPA does not believe that it is necessary to specify a
procedure because it is simply a depth measurement. Specifying a
technique may also hinder the development of site-specific techniques
to reduce worker exposure. The EPA believes that wetting agents are
safer than foam blankets because foam blankets present a potential
safety hazard. The foam traps the hydrogen gas and chromic acid mist in
the foam layer; if these gases build up and a spark is generated, a
hydrogen explosion will result. As a means of encouraging wetting agent
use over foam blankets, sources using wetting agents do not have to
conduct a performance test unless they want to set a surface tension
limit other than the default value of 45 dynes/cm. The EPA believes
that the compliance timeframes in the final rule will allow sources
that currently use foam blankets the opportunity to explore the use of
wetting agents. Sources that wish to continue using foam blankets will
be required to conduct a performance test.
5. Frequency of Monitoring Associated With Fume Suppressants
    There were over 20 comments related to the frequency of monitoring
surface tension. Several of these commenters made recommendations for
alternate monitoring schedules, ranging from daily to monthly
monitoring, in place of the 4-hour schedule. Among the reasons cited
for decreasing the surface tension monitoring frequency were that
surface tension does not change on a daily or weekly basis, measuring
surface tension is very time-consuming and could require someone full-
time if there were multiple tanks, and frequent monitoring results in
increased worker exposure.
    Thirteen commenters provided remarks regarding the burden of hourly
testing for sources using foam blankets. The commenters noted that foam
blankets that are used according to manufacturer's instructions are
designed to last 24 hours provided the air is not agitated at the
surface near the anodes and freeboard height is adequate. Therefore,
visual observation is adequate for determining foam blanket
effectiveness. Other commenters stated that the excessive monitoring
requirements for foam blankets discourage their use, yet several States
recommend or require foam blankets with less testing and recordkeeping
than that proposed by the EPA.
    In response to comments and some data received, the EPA recognizes
that the 4-hour surface tension monitoring frequency specified in the
proposed rule may be burdensome, and in some cases, unnecessary. The
EPA has insufficient data, however, to establish the monitoring
frequency that is appropriate for each mode of bath operation.
Therefore, the final rule allows a decrease in monitoring frequency if
no exceedances occur. Section 63.343(c)(5)(ii)(B) specifies that the
surface tension be measured once every 4-hours of tank operation for
the first 40 hours of tank operation after the compliance date. If no
exceedances occur, monitoring can occur once every 8 hours of tank
operation. Once there are again no exceedances during 40 hours of tank
operation, surface tension measurement may be conducted once every 40
hours of tank operation on an on-going basis, until an exceedance
occurs. Once an exceedance of the [[Page 4960]] standard occurs or the
electroplating solution is changed out, the original monitoring
schedule must be resumed.
    Likewise, the final rule contains allowances to decrease the
frequency of monitoring foam blanket thickness. The proposed hourly
frequency is based on the EPA's experience that foam blankets can
deplete quickly and must be closely monitored. The final rule is
unchanged in that sources using a foam blanket must conduct a
performance test, and the initial monitoring frequency is once per
hour. However, as with wetting agents, the final rule allows a decrease
in monitoring frequency if no exceedances occur. Section
63.343(c)(6)(ii)(B) specifies that the foam blanket thickness be
measured once every hour of tank operation for the first 40 hours of
tank operation after the compliance date. If no exceedances occur, the
time between monitoring may be increased to once every 4 hours of tank
operation. Once there are no exceedances during 40 hours of tank
operation, foam blanket thickness measurement may be conducted once
every 8 hours of tank operation on an on-going basis. As with wetting
agents, if there is an exceedance or if the electroplating bath is
changed out, the original monitoring schedule must be resumed.
I. Selection of Test Methods
    Three commenters requested that CARB Method 425 be evaluated for
equivalency, and if determined to be equivalent, be identified as such
in the rule. These commenters also stated that sources that have
performed this test should not have to retest. Four commenters asked
whether retesting will be required if sources have conducted
performance tests previously using 306, 306A, or an equivalent test
method.
    Section 63.344(c)(2) identifies the conditions under which the CARB
Method 425 is considered equivalent. Basically, the acceptability of
this test method will depend upon the analysis rather than the sampling
train or sampling procedure. Regarding the issue of whether retesting
is required, Sec. 63.344(b) of the final rule outlines the criteria
that must be met for a previous source test to be acceptable.
    Two commenters requested that the rule provide guidance on how to
verify compliance when both chromium anodizing and hard chromium
electroplating tanks are vented to a common control device. Three
commenters pointed out that the regulation does not account for the
situation in which chromium electroplating sources share a ventilation
system with nonchromium sources that could introduce dilution air.
Three commenters noted that it is extremely difficult to reconfigure
some existing systems in such a way that only the emissions from
chromium electroplating or anodizing are tested.
    There are basically two situations involving multiple tanks
manifolded to one control system: (1) The multiple tanks include a
chromium electroplating or chromium anodizing tank among other tanks
not affected by the rule; or (2) the multiple tanks include chromium
tanks performing different operations (e.g., electroplating and
anodizing) or hard chromium tanks subject to different emission limits
(e.g., a new tank and an existing small tank), which may or may not be
controlled with nonaffected sources. Section 63.344(e) of the final
rule includes compliance provisions for both of these situations.
J. Selection of Reporting and Recordkeeping Requirements
    Several commenters stated that the frequency of recordkeeping and
reporting outlined in the proposed rule was overly burdensome and
suggested several alternatives. Seven commenters stated that the types
of recordkeeping required by the rule are inappropriate. In general,
the commenters remarked that records, such as the amount of chemicals
used and purchased and the amount of fume suppressant material added do
not indicate compliance. Two commenters stated that recordkeeping
requirements be limited to only surface tension measurements because
that measurement is the basis of compliance. One commenter indicated
there is no environmental benefit to keeping records of gas velocities,
pressure drops, washdown conditions, and scrubber water chromium
concentrations. Two commenters stated that maintaining records at a
facility for 5 years is excessive; a more appropriate length of time
would be 3 years. One commenter suggested a minimum of 2 years.
    Two commenters suggested that the reporting schedule be replaced
with a requirement that the source submit an annual certification that
necessary control parameters have been met, consistent with the annual
certification requirements of title V. Another commenter indicated that
sources should not be required to submit compliance reports if the
source's permitting agency inspects the onsite records annually.
Finally, one commenter suggested that the rule allow a reduced
reporting frequency after 2 years if sources do not experience
exceedances of any State or Federal emission standards.
    Seven commenters stated that the costs associated with the
monitoring and recordkeeping constituted an unnecessary burden to both
large and small facilities. These commenters also noted that the EPA
underestimated the costs associated with monitoring, reporting, and
recordkeeping. Two of the commenters stated that small businesses do
not have the resources to keep extensive records. Another commenter
pointed out that the EPA has recognized differences in large and small
facilities in selecting MACT emission standards and should also
recognize differences between large and small facilities in selecting
reporting, recordkeeping, and permitting requirements.
    To respond to comments received and to reduce the burden on the
many area sources that will be subject to these standards, the
monitoring, reporting, and recordkeeping requirements have been reduced
in the final rule to the extent possible while still providing the EPA
with the ability to determine a source's continuous compliance status.
The recordkeeping requirements are contained in Sec. 63.346 of the
final rule. The EPA concurs that the records required to be kept should
correspond specifically to that which is required to demonstrate
compliance. As such, recordkeeping associated with fume suppressants
requires only that sources maintain records of the date and time of
surface tension or foam blanket thickness measurements, as appropriate,
the value measured, and the date and time of additions of fume
suppressant to the bath. Likewise, the recordkeeping associated with
the add-on air pollution control devices is reduced to the extent that
the monitoring requirements have been reduced. Sources will have to
keep records of pressure drop and velocity pressure, as appropriate, as
well as records to document adherence with the O&M plan required by
Sec. 63.342(f)(3).
    The final rule is unchanged from proposal in that it requires that
owners or operators of affected sources maintain records for a period
of 5 years following each occurrence, measurement, maintenance,
corrective action, report, or record. This requirement is consistent
with the General Provisions and with the title V permit program. The
EPA believes retention of records for 5 years allows the EPA to
establish a source's history and pattern of compliance for purposes of
determining the appropriate level of enforcement action.
    The final rule also requires submission of on-going compliance
status reports to document whether a [[Page 4961]] source has been in
continuous compliance with the standards. The final rule contains
different reporting schedules for major and area sources. Major sources
are required to submit on-going compliance status reports semiannually,
unless an exceedance occurs, at which time quarterly reports would be
required. This change is analogous to the requirements of the final
General Provisions, which had only been proposed at the time of this
proposed rulemaking.
    In an effort to reduce the burden on area sources, the final rule
allows area sources to complete an annual compliance report, and allows
the source to maintain the report on site, to be made available to the
Administrator or permitting authority upon request. The EPA recognizes
that many permitting authorities may not be equipped to handle reports
from area sources, and that these sources may not be the sources of
primary concern to the authority. However, the requirements in the
final rule do not alleviate affected area sources from complying with
the reporting requirements of State or Federal operating permit
programs under title V. The rule does require that area sources submit
reports semiannually if exceedances occur, or if required by the
Administrator or permitting authority.
    Sources using a trivalent chromium bath are only required to keep
records of the bath ingredients purchased. These sources must submit an
initial notification and notification of compliance status, but are not
required to submit on-going compliance status reports.
    As a result of the reduced monitoring, reporting, and recordkeeping
in the final rule compared to the proposed rule, the costs of these
activities have also been reduced. A comparison of the cost of the
monitoring, reporting, and recordkeeping associated with the final and
proposed rules was presented in section III.B of this preamble for each
of the regulated source categories.
    One commenter requested that the rule clearly state which sections
of the General Provisions apply to chromium electroplating sources and
which do not apply. To eliminate confusion concerning the applicability
of the General Provisions to this source category, Table 1 of subpart N
lists which of the General Provisions to part 63 apply and which do not
apply to affected sources.

K. Operating Permit Program

    Eleven commenters stated that area sources should not be required
to obtain title V operating permits because the costs for area sources
to obtain title V permits would be overly burdensome, and the emissions
from these sources may be insignificant. Three of these commenters
suggested that the rule explicitly state that a permit is required only
for applicable emissions units at nonmajor sources. Two commenters
asked that a general permit be included in the final rule to reduce the
burden for small facilities. Another commenter stated that a title V
permit is not necessary because existing requirements are enforceable
through State and local permits. This commenter and one other commenter
pointed out that because area sources are not likely to be subject to
multiple MACT standards or to employ emissions averaging and complex
alternate operating scenarios, title V permits do not benefit the area
sources.
    Two commenters stated that in preparing their title V permit
programs, States did not anticipate a need for emission-unit specific
permits at nonmajor sources, and inclusion of nonmajor sources under
title V will require that many local agencies revise their permit
programs. Two other commenters stated that States will not have the
resources for completing title V permits for area sources; some states
have exempted nonmajor sources from their permitting programs until the
nonmajor source permitting rule is promulgated in the late 1990's.
    The EPA believes that requiring all sources that are subject to the
standards, including area sources, to obtain title V operating permits
is important because of the toxicity of chromium compounds and the
close proximity of many of these sources to residential areas. The EPA
believes that permitting area sources will not be overly burdensome to
permitting authorities and affected sources for the reasons given
below.
    First, many States are already permitting these sources under their
State permit programs. The preamble to the final part 70 rule states
that ``some nonmajor sources would already be permitted at the State
level, and therefore would have some experience with the permitting
process and completing permit applications.'' Therefore, a State would
have little reason to defer title V permitting of sources that already
have State operating permits. Second, the burden may be reduced
significantly by issuing general permits to these sources. According to
the preamble to the final part 70 rule, general permits ``* * * provide
an alternative means for permitting sources for which the procedures of
the normal permitting process would be overly burdensome, such as area
sources under section 112* * *'' Under this option, States would
develop a single general permit for this source category and issue it
to individual sources; or alternatively, a letter or certification may
be used. The burden would also be reduced by using general permits
because public participation and the EPA and affected State review is
only necessary when the initial general permit is drafted and issued.
When subsequent general permits are issued to individual sources, these
activities are not required. Finally, States are developing small
business assistance programs (SBAP's) to assist these types of sources
with the permitting process that will be funded using the annual fees
collected from permitted sources. Small businesses may also be eligible
for reduced permitting fees. Also, the EPA is developing a guidance
document, scheduled to be completed by January 1995, which will include
sample forms for monitoring, recordkeeping, and reporting requirements,
and a simplified general operating permit.
    Under title V, sources must include information on all emission
points (except those considered insignificant under the State or local
permit program) in their permit application. However, only these
emission points that are subject to regulation will be addressed in the
permit.

VI. Administrative Requirements

A. Docket

    The docket for this rulemaking is A-88-02. The docket is an
organized and complete file of all the information submitted to or
otherwise considered by the EPA in the development of this rulemaking.
The principal purposes of the docket are: (1) To allow interested
parties a means to identify and locate documents so that they can
effectively participate in the rulemaking process; and (2) to serve as
the record in case of judicial review (except for interagency review
materials) [section 307(d)(7)(A) of the Act]. The docket is available
for public inspection at the EPA's Air and Radiation Docket and
Information Center, the location of which is given in the ADDRESSES
section of this notice.

B. Executive Order 12866

    Under Executive Order 12866 [58 FR 51735 (October 4, 1993)], the
Agency must determine whether the regulatory action is ``significant''
and therefore subject to OMB review and the requirements of the
Executive Order. The Order defines ``significant regulatory action'' as
one that is likely to result in a rule that may: [[Page 4962]]
    (1) Have an annual effect on the economy of $100 million or more,
or adversely affect in a material way the economy, a sector of the
economy, productivity, competition, jobs, the environment, public
health or safety, or State, local, or tribal governments or
communities;
    (2) Create a serious inconsistency or otherwise interfere with an
action taken or planned by another agency;
    (3) Materially alter the budgetary impact of entitlements, grants,
user fees, or loan programs or the rights and obligations of recipients
thereof; or
    (4) Raise novel legal or policy issues arising out of legal
mandates, the President's priorities, or the principles set forth in
the Executive Order.
    Pursuant to the terms of the Executive Order 12866, the Office of
Management and Budget (OMB) has notified the EPA that this action is a
``significant regulatory action'' within the meaning of the Executive
Order. For this reason, this action was sent to OMB for review. Changes
made in response to OMB suggestions or recommendations will be
documented in the public record.

C. Paperwork Reduction Act

    Information collection requirements associated with this rule have
been approved by OMB under the provisions of the Paperwork Reduction
Act of 1980, 44 U.S.C. 3501 et seq., and have been assigned OMB control
number 2060-0327. An Information Collection Request (ICR) document has
been prepared by the EPA (ICR No. 1611.02) to reflect the changed
information requirements of the final rule and has been submitted to
OMB for review. A copy may be obtained from Sandy Farmer, Information
Policy Branch, EPA, 401 M Street, SW. (2136), Washington, DC 20460, or
by calling (202) 260-2740.
    The public reporting burden for this collection of information is
estimated to average 34 hours per respondent in the first year, 117
hours per respondent in the second year, and 297 hours per respondent
in the third year. This estimate includes the time required for
reviewing instructions, searching existing data sources, gathering and
maintaining the data needed, and completing and reviewing the
collection of information. The burden is greatest in the second and
third years because this is when performance tests will be conducted.
An on-going burden of 104 hours per respondent is representative of the
burden following the third year.
    Send comments regarding the burden estimate or any other aspect of
this collection of information, including suggestions for reducing this
burden, to Chief, Information Policy Branch, EPA, 401 M Street, SW.
(2136), Washington, DC 20460; and to the Office of Information and
Regulatory Affairs, Office of Management and Budget, Washington, DC
20503, marked ``Attention: Desk Officer for EPA.''

D. Regulatory Flexibility Act

    The Regulatory Flexibility Act of 1980 (5 U.S.C. 601 et seq.)
requires that a Regulatory Flexibility Analysis be performed for all
rules that have ``significant impact on a substantial number of small
entities.'' If a preliminary analysis indicates that a proposed
regulation would have a significant economic impact on 20 percent or
more of small entities, then a regulatory flexibility analysis must be
prepared.
    Present Regulatory Flexibility Act guidelines define an economic
impact as significant if it meets one of the following criteria:
    (1) Compliance increases annual production costs by more than 5
percent, assuming costs are passed on to consumers;
    (2) Compliance costs as a percentage of sales for small entities
are at least 10 percent more than compliance costs as a percentage of
sales for large entities;
    (3) Capital costs of compliance represent a ``significant'' portion
of capital available to small entities, considering internal cash flow
plus external financial capabilities; or
    (4) Regulatory requirements are likely to result in closures of
small entities.
    Using the Small Business Administration's definition of a small
business for SIC Code 3471 of less than 500 employees, it has been
determined that none of the above criteria are triggered. In the hard
chromium electroplating source category, the number of small businesses
is estimated to be 1,170. None of the regulatory alternatives
considered will significantly impact 20 percent of this operation. For
example, the estimated number of closures is approximated as less than
5 percent. Likewise, the standards for decorative chromium
electroplaters and chromium anodizers would not cause any of the above
criteria to be triggered.
    Pursuant to the provisions of 5 U.S.C. 605(b), I hereby certify
that this rule will not have a significant economic impact on a
substantial number of small business entities because the number of
small business entities that would be affected is not significant.

E. Miscellaneous

    In accordance with section 117 of the Act, publication of this
promulgated rule was preceded by consultation with appropriate advisory
committees, independent experts, and Federal departments and agencies.
    This regulation will be reviewed 8 years from the date of
promulgation. This review will include an assessment of such factors as
evaluation of the residual health risks, any overlap with other
programs, the existence of alternative methods, enforceability,
improvements in emission control technology and health data, and the
recordkeeping and reporting requirements.

List of Subjects in 40 CFR Parts 9 and 63

    Environmental protection, Air pollution control, Hazardous
substances, Incorporation by reference, Reporting and recordkeeping
requirements.

    Dated: November 22, 1994.
Carol M. Browner,
Administrator.

    For the reasons set out in the preamble, title 40, Chapter I of the
Code of Federal Regulations is amended as set forth below.

PART 9--[AMENDED]

    1. The authority citation for part 9 continues to read as follows:

    Authority: 7 U.S.C. 135 et seq., 1235-136y; 15 U.S.C. 2001,
2003, 2005, 2006, 2601-2671; 21 U.S.C. 331j, 346a, 348; 31 U.S.C.
9701; 33 U.S.C. 1251 et seq., 1311, 1313d, 1314, 1321, 1326, 1330,
1344, 1345 (d) and (e), 1361; E.O. 11735, 38 FR 21243, 3 CFR, 1971-
1975; Comp. p. 973; 42 U.S.C. 241, 242b, 243, 246, 300f, 300g, 300g-
1, 300g-2, 300g-3, 300g-4, 300g-5, 300g-6, 300j-1, 300j-2, 300j-3,
300j-4, 300j-9, 1857 et seq., 6901-6992k, 7401-7671q, 7542, 9601-
9657, 11023, 11048.

    2. Section 9.1 is amended by adding a new entry to the table under
the indicated heading in numerical order to read as follows:

Sec. 9.1  OMB approvals under the Paperwork Reduction Act.

* * * * *

------------------------------------------------------------------------
                                                             OMB control
                      40 CFR citation                            No.
------------------------------------------------------------------------

                  *        *        *        *        *
National Emission Standards for Hazardous Air Pollutants
 for Source Categories:


                  *        *        *        *        *
63.345-63.347..............................................    2060-0327


                  *        *        *        *        *
------------------------------------------------------------------------

[[Page 4963]] PART 63--[AMENDED]

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

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

    2. Section 63.14 is amended by adding paragraphs (b) (4) and (5) to
read as follows:

Sec. 63.14  Incorporation by reference.

* * * * *
    (b) * * *
    (4) ASTM D 1193-77, Standard Specification for Reagent Water, IBR
approved for Method 306, section 4.1.1 and section 4.4.2, of appendix A
to part 63.
    (5) ASTM D 1331-89, Standard Test Methods for Surface and
Interfacial Tension of Solutions of Surface Active Agents, IBR approved
for Method 306B, section 2.2, section 3.1, and section 4.2, of appendix
A to part 63.
* * * * *
    3. By adding a new subpart N to read as follows:
Subpart N--National Emission Standards for Chromium Emissions From Hard
and Decorative Chromium Electroplating and Chromium Anodizing Tanks
Sec.
63.340  Applicability and designation of sources.
63.341  Definitions and nomenclature.
63.342  Standards.
63.343  Compliance provisions.
63.344  Performance test requirements and test methods.
63.345  Provisions for new and reconstructed sources.
63.346  Recordkeeping requirements.
63.347  Reporting requirements.

Table 1 to Subpart N of Part 63--General Provisions Applicability to
Subpart N

Subpart N--National Emission Standards for Chromium Emissions From
Hard and Decorative Chromium Electroplating and Chromium Anodizing
Tanks

Sec. 63.340  Applicability and designation of sources.

    (a) The affected source to which the provisions of this subpart
apply is each chromium electroplating or chromium anodizing tank at
facilities performing hard chromium electroplating, decorative chromium
electroplating, or chromium anodizing.
    (b) Owners or operators of affected sources subject to the
provisions of this subpart must also comply with the requirements of
subpart A of this part, according to the applicability of subpart A of
this part to such sources, as identified in Table 1 of this subpart.
    (c) Process tanks associated with a chromium electroplating or
chromium anodizing process, but in which neither chromium
electroplating nor chromium anodizing is taking place, are not subject
to the provisions of this subpart. Examples of such tanks include, but
are not limited to, rinse tanks, etching tanks, and cleaning tanks.
Likewise, tanks that contain a chromium solution, but in which no
electrolytic process occurs, are not subject to this subpart. An
example of such a tank is a chrome conversion coating tank where no
electrical current is applied.
    (d) Affected sources in which research and laboratory operations
are performed are exempt from the provisions of this subpart when such
operations are taking place.
    (e) The owner or operator of an affected source subject to the
requirements of this subpart is required to obtain a title V permit
from the permitting authority in which the affected source is located.

Sec. 63.341  Definitions and nomenclature.

    (a) Definitions. Terms used in this subpart are defined in the Act,
in subpart A of this part, or in this section. For the purposes of
subpart N of this part, if the same term is defined in subpart A of
this part and in this section, it shall have the meaning given in this
section.
    Add-on air pollution control device means equipment installed in
the ventilation system of chromium electroplating and anodizing tanks
for the purposes of collecting and containing chromium emissions from
the tank(s).
    Air pollution control technique means any method, such as an add-on
air pollution control device or a chemical fume suppressant, that is
used to reduce chromium emissions from chromium electroplating and
chromium anodizing tanks.
    Base metal means the metal or metal alloy that comprises the
workpiece.
    Bath component means the trade or brand name of each component(s)
in trivalent chromium plating baths. For trivalent chromium baths, the
bath composition is proprietary in most cases. Therefore, the trade or
brand name for each component(s) can be used; however, the chemical
name of the wetting agent contained in that component must be
identified.
    Chemical fume suppressant means any chemical agent that reduces or
suppresses fumes or mists at the surface of an electroplating or
anodizing bath; another term for fume suppressant is mist suppressant.
    Chromic acid means the common name for chromium anhydride
(CrO<INF>3).
    Chromium anodizing means the electrolytic process by which an oxide
layer is produced on the surface of a base metal for functional
purposes (e.g., corrosion resistance or electrical insulation) using a
chromic acid solution. In chromium anodizing, the part to be anodized
acts as the anode in the electrical circuit, and the chromic acid
solution, with a concentration typically ranging from 50 to 100 grams
per liter (g/L), serves as the electrolyte.
    Chromium electroplating or chromium anodizing tank means the
receptacle or container in which hard or decorative chromium
electroplating or chromium anodizing occurs.
    Composite mesh-pad system means an add-on air pollution control
device typically consisting of several mesh-pad stages. The purpose of
the first stage is to remove large particles. Smaller particles are
removed in the second stage, which consists of the composite mesh pad.
A final stage may remove any reentrained particles not collected by the
composite mesh pad.
    Decorative chromium electroplating means the process by which a
thin layer of chromium (typically 0.003 to 2.5 microns) is
electrodeposited on a base metal, plastic, or undercoating to provide a
bright surface with wear and tarnish resistance. In this process, the
part(s) serves as the cathode in the electrolytic cell and the solution
serves as the electrolyte. Typical current density applied during this
process ranges from 540 to 2,400 Amperes per square meter (A/m<SUP>2)
for total plating times ranging between 0.5 to 5 minutes.
    Electroplating or anodizing bath means the electrolytic solution
used as the conducting medium in which the flow of current is
accompanied by movement of metal ions for the purposes of
electroplating metal out of the solution onto a workpiece or for
oxidizing the base material.
    Emission limitation means, for the purposes of this subpart, the
concentration of total chromium allowed to be emitted expressed in
milligrams per dry standard cubic meter (mg/dscm), or the allowable
surface tension expressed in dynes per centimeter (dynes/cm).
    Facility means the major or area source at which chromium
electroplating or chromium anodizing is performed.
    Fiber-bed mist eliminator means an add-on air pollution control
device that removes contaminants from a gas stream through the
mechanisms of inertial impaction and Brownian diffusion. These devices
are typically installed downstream of another control device, which
serves to prevent plugging, and [[Page 4964]] consist of one or more
fiber beds. Each bed consists of a hollow cylinder formed from two
concentric screens; the fiber between the screens may be fabricated
from glass, ceramic plastic, or metal.
    Foam blanket means the type of chemical fume suppressant that
generates a layer of foam across the surface of a solution when current
is applied to that solution.
    Fresh water means water, such as tap water, that has not been
previously used in a process operation or, if the water has been
recycled from a process operation, it has been treated and meets the
effluent guidelines for chromium wastewater.
    Hard chromium electroplating or industrial chromium electroplating
means a process by which a thick layer of chromium (typically 1.3 to
760 microns) is electrodeposited on a base material to provide a
surface with functional properties such as wear resistance, a low
coefficient of friction, hardness, and corrosion resistance. In this
process, the part serves as the cathode in the electrolytic cell and
the solution serves as the electrolyte. Hard chromium electroplating
process is performed at current densities typically ranging from 1,600
to 6,500 A/m<SUP>2 for total plating times ranging from 20 minutes to
36 hours depending upon the desired plate thickness.
    Hexavalent chromium means the form of chromium in a valence state
of +6.
    Large, hard chromium electroplating facility means a facility that
performs hard chromium electroplating and has a maximum cumulative
potential rectifier capacity greater than or equal to 60 million
ampere-hours per year (amp-hr/yr).
    Maximum cumulative potential rectifier capacity means the summation
of the total installed rectifier capacity associated with the hard
chromium electroplating tanks at a facility, expressed in amperes,
multiplied by the maximum potential operating schedule of 8,400 hours
per year and 0.7, which assumes that electrodes are energized 70
percent of the total operating time. The maximum potential operating
schedule is based on operating 24 hours per day, 7 days per week, 50
weeks per year.
    Operating parameter value means a minimum or maximum value
established for a control device or process parameter which, if
achieved by itself or in combination with one or more other operating
parameter values, determines that an owner or operator is in continual
compliance with the applicable emission limitation or standard.
    Packed-bed scrubber means an add-on air pollution control device
consisting of a single or double packed bed that contains packing media
on which the chromic acid droplets impinge. The packed-bed section of
the scrubber is followed by a mist eliminator to remove any water
entrained from the packed-bed section.
    Research or laboratory operation means an operation whose primary
purpose is for research and development of new processes and products,
that is conducted under the close supervision of technically trained
personnel, and that is not involved in the manufacture of products for
commercial sale in commerce, except in a de minimis manner.
    Small, hard chromium electroplating facility means a facility that
performs hard chromium electroplating and has a maximum cumulative
potential rectifier capacity less than 60 million amp-hr/yr.
    Stalagmometer means a device used to measure the surface tension of
a solution.
    Surface tension means the property, due to molecular forces, that
exists in the surface film of all liquids and tends to prevent liquid
from spreading.
    Tank operation means the time in which current and/or voltage is
being applied to a chromium electroplating tank or a chromium anodizing
tank.
    Tensiometer means a device used to measure the surface tension of a
solution.
    Trivalent chromium means the form of chromium in a valence state of
+3.
    Trivalent chromium process means the process used for
electrodeposition of a thin layer of chromium onto a base material
using a trivalent chromium solution instead of a chromic acid solution.
    Wetting agent means the type of chemical fume suppressant that
reduces the surface tension of a liquid.
    (b) Nomenclature. The nomenclature used in this subpart has the
following meaning:
    (1) AMR=the allowable mass emission rate from each type of affected
source subject to the same emission limitation in milligrams per hour
(mg/hr).
    (2) AMR<INF>sys=the allowable mass emission rate from affected
sources controlled by an add-on air pollution control device
controlling emissions from multiple sources in mg/hr.
    (3) EL=the applicable emission limitation from Sec. 63.342 in
milligrams per dry standard cubic meter (mg/dscm).
    (4) IA<INF>total=the sum of all inlet duct areas from both affected
and nonaffected sources in meters squared.
    (5) IDA<INF>i=the total inlet area for all ducts associated with
affected sources in meters squared.
    (6) IDA<INF>i,a=the total inlet duct area for all ducts conveying
chromic acid from each type of affected source performing the same
operation, or each type of affected source subject to the same emission
limitation in meters squared.
    (7) VR=the total of ventilation rates for each type of affected
source subject to the same emission limitation in dry standard cubic
meters per minute (dscm/min).
    (8) VR<INF>inlet=the total ventilation rate from all inlet ducts
associated with affected sources in dscm/min.
    (9) VR<INF>inlet,a=the total ventilation rate from all inlet ducts
conveying chromic acid from each type of affected source performing the
same operation, or each type of affected source subject to the same
emission limitation in dscm/min.
    (10) VR<INF>tot=the average total ventilation rate for the three
test runs as determined at the outlet by means of the Method 306 in
appendix A of this part testing in dscm/min.

Sec. 63.342  Standards.

    (a) Each owner or operator of an affected source subject to the
provisions of this subpart shall comply with these requirements on and
after the compliance dates specified in Sec. 63.343(a). All affected
sources are regulated by applying maximum achievable control
technology.
    (b) Applicability of emission limits. (1) The emission limitations
in this section apply only during tank operation, and also apply during
periods of startup and shutdown as these are routine occurrences for
affected sources subject to this subpart. The emission limitations do
not apply during periods of malfunction, but the work practice
standards that address operation and maintenance and that are required
by paragraph (f) of this section must be followed during malfunctions.
    (2) If an owner or operator is controlling a group of tanks with a
common add-on air pollution control device, the emission limitations of
paragraphs (c), (d), and (e) of this section apply whenever any one
affected source is operated. The emission limitation that applies to
the group of affected sources is:
    (i) The emission limitation identified in paragraphs (c), (d), and
(e) of this section if the affected sources are performing the same
type of operation (e.g., hard chromium electroplating), are subject to
the same emission limitation, and are not controlled by an add-on air
pollution control device also controlling nonaffected
sources; [[Page 4965]]
    (ii) The emission limitation calculated according to
Sec. 63.344(e)(3) if affected sources are performing the same type of
operation, are subject to the same emission limitation, and are
controlled with an add-on air pollution control device that is also
controlling nonaffected sources; and
    (iii) The emission limitation calculated according to
Sec. 63.344(e)(4) if affected sources are performing different types of
operations, or affected sources are performing the same operations but
subject to different emission limitations, and are controlled with an
add-on air pollution control device that may also be controlling
emissions from nonaffected sources.
    (c)(1) Standards for hard chromium electroplating tanks. During
tank operation, each owner or operator of an existing, new, or
reconstructed affected source shall control chromium emissions
discharged to the atmosphere from that affected source by not allowing
the concentration of total chromium in the exhaust gas stream
discharged to the atmosphere to exceed:
    (i) 0.015 milligrams of total chromium per dry standard cubic meter
(mg/dscm) of ventilation air (6.6 x 10<SUP>-6 grains per dry standard
cubic foot [gr/dscf]); or
    (ii) 0.03 mg/dscm (1.3 x 10<SUP>-5 gr/dscf) if the hard chromium
electroplating tank is an existing affected source and is located at a
small, hard chromium electroplating facility.
    (2)(i) An owner or operator may demonstrate the size of a hard
chromium electroplating facility through the definitions in
Sec. 63.341(a). Alternatively, an owner or operator of a facility with
a maximum cumulative potential rectifier capacity of 60 million amp-hr/
yr or more may be considered small if the actual cumulative rectifier
capacity is less than 60 million amp-hr/yr as demonstrated using the
following procedures:
    (A) If records show that the facility's previous annual actual
rectifier capacity was less than 60 million amp-hr/yr, by using
nonresettable ampere-hr meters and keeping monthly records of actual
ampere-hr usage for each 12-month rolling period following the
compliance date in accordance with Sec. 63.346(b)(12). The actual
cumulative rectifier capacity for the previous 12-month rolling period
shall be tabulated monthly by adding the capacity for the current month
to the capacities for the previous 11 months; or
    (B) By accepting a Federally-enforceable limit on the maximum
cumulative potential rectifier capacity of a hard chromium
electroplating facility through the title V permit required by
Sec. 63.340(e), and by maintaining monthly records in accordance with
Sec. 63.346(b)(12) to demonstrate that the limit has not been exceeded.
The actual cumulative rectifier capacity for the previous 12-month
rolling period shall be tabulated monthly by adding the capacity for
the current month to the capacities for the previous 11 months.
    (ii) Once the monthly records required to be kept by
Sec. 63.346(b)(12) and by this paragraph show that the actual
cumulative rectifier capacity over the previous 12-month rolling period
corresponds to the large designation, the owner or operator is subject
to the emission limitation identified in paragraph (c)(1)(i) of this
section, in accordance with the compliance schedule of
Sec. 63.343(a)(5).
    (d) Standards for decorative chromium electroplating tanks using a
chromic acid bath and chromium anodizing tanks. During tank operation,
each owner or operator of an existing, new, or reconstructed affected
source shall control chromium emissions discharged to the atmosphere
from that affected source by either:
    (1) Not allowing the concentration of total chromium in the exhaust
gas stream discharged to the atmosphere to exceed 0.01 mg/dscm
(4.4 x 10<SUP>-6 gr/dscf); or
    (2) If a chemical fume suppressant containing a wetting agent is
used, by not allowing the surface tension of the electroplating or
anodizing bath contained within the affected source to exceed 45 dynes
per centimeter (dynes/cm) (3.1 x 10<SUP>-3 pound-force per foot
[lb<INF>f/ft]) at any time during operation of the tank.
    (e) Standards for decorative chromium electroplating tanks using a
trivalent chromium bath. (1) Each owner or operator of an existing,
new, or reconstructed decorative chromium electroplating tank that uses
a trivalent chromium bath that incorporates a wetting agent as a bath
ingredient is subject to the recordkeeping and reporting requirements
of Secs. 63.346(b)(14) and 63.347(i), but are not subject to the work
practice requirements of paragraph (f) of this section, or the
continuous compliance monitoring requirements in Sec. 63.343(c). The
wetting agent must be an ingredient in the trivalent chromium bath
components purchased from vendors.
    (2) Each owner or operator of an existing, new, or reconstructed
decorative chromium electroplating tank that uses a trivalent chromium
bath that does not incorporate a wetting agent as a bath ingredient is
subject to the standards of paragraph (d) of this section.
    (3) Each owner or operator of existing, new, or reconstructed
decorative chromium electroplating tank that had been using a trivalent
chromium bath that incorporates a wetting agent and ceases using this
type of bath must fulfill the reporting requirements of
Sec. 63.347(i)(3) and comply with the applicable emission limitation
within the timeframe specified in Sec. 63.343(a)(7).
    (f) Work practice standards. The work practice standards of this
section address operation and maintenance practices. All owners or
operators subject to the standards in paragraphs (c) and (d) of this
section are subject to these work practice standards.
    (1)(i) At all times, including periods of startup, shutdown, and
malfunction, owners or operators shall operate and maintain any
affected source, including associated air pollution control devices and
monitoring equipment, in a manner consistent with good air pollution
control practices, consistent with the operation and maintenance plan
required by paragraph (f)(3) of this section.
    (ii) Malfunctions shall be corrected as soon as practicable after
their occurrence in accordance with the operation and maintenance plan
required by paragraph (f)(3) of this section.
    (iii) Operation and maintenance requirements established pursuant
to section 112 of the Act are enforceable independent of emissions
limitations or other requirements in relevant standards.
    (2)(i) Determination of whether acceptable operation and
maintenance procedures are being used will be based on information
available to the Administrator, which may include, but is not limited
to, monitoring results; review of the operation and maintenance plan,
procedures, and records; and inspection of the source.
    (ii) Based on the results of a determination made under paragraph
(f)(2)(i) of this section, the Administrator may require that an owner
or operator of an affected source make changes to the operation and
maintenance plan required by paragraph (f)(3) of this section for that
source. Revisions may be required if the Administrator finds that the
plan:
    (A) Does not address a malfunction that has occurred;
    (B) Fails to provide for the operation of the affected source, the
air pollution control techniques, or the control system and process
monitoring equipment during a malfunction in a manner consistent with
good air pollution control practices; or [[Page 4966]]
    (C) Does not provide adequate procedures for correcting
malfunctioning process equipment, air pollution control techniques, or
monitoring equipment as quickly as practicable.
    (3) Operation and maintenance plan. (i) The owner or operator of an
affected source subject to the work practices of paragraph (f) of this
section shall prepare an operation and maintenance plan to be
implemented no later than the compliance date. The plan shall be
incorporated by reference into the source's title V permit and shall
include the following elements:
    (A) The plan shall specify the operation and maintenance criteria
for the affected source, the add-on air pollution control device (if
such a device is used to comply with the emission limits), and the
process and control system monitoring equipment, and shall include a
standardized checklist to document the operation and maintenance of
this equipment;
    (B) For sources using an add-on air pollution control device or
monitoring equipment to comply with this subpart, the plan shall
incorporate the work practice standards for that device or monitoring
equipment, as identified in Table 1 of this section, if the specific
equipment used is identified in Table 1 of this section;
    (C) If the specific equipment used is not identified in Table 1 of
this section, the plan shall incorporate proposed work practice
standards. These proposed work practice standards shall be submitted to
the Administrator for approval as part of the submittal required under
Sec. 63.343(d);
    (D) The plan shall specify procedures to be followed to ensure that
equipment or process malfunctions due to poor maintenance or other
preventable conditions do not occur; and
    (E) The plan shall include a systematic procedure for identifying
malfunctions of process equipment, add-on air pollution control
devices, and process and control system monitoring equipment and for
implementing corrective actions to address such malfunctions.
    (ii) If the operation and maintenance plan fails to address or
inadequately addresses an event that meets the characteristics of a
malfunction at the time the plan is initially developed, the owner or
operator shall revise the operation and maintenance plan within 45 days
after such an event occurs. The revised plan shall include procedures
for operating and maintaining the process equipment, add-on air
pollution control device, or monitoring equipment during similar
malfunction events, and a program for corrective action for such
events.
    (iii) Recordkeeping associated with the operation and maintenance
plan is identified in Sec. 63.346(b). Reporting associated with the
operation and maintenance plan is identified in Sec. 63.347 (g) and (h)
and paragraph (f)(3)(iv) of this section.
    (iv) If actions taken by the owner or operator during periods of
malfunction are inconsistent with the procedures specified in the
operation and maintenance plan required by paragraph (f)(3)(i) of this
section, the owner or operator shall record the actions taken for that
event and shall report such actions within 2 working days after
commencing actions inconsistent with the plan. This report shall be
followed by a letter within 7 working days after the end of the event,
unless the owner or operator makes alternative reporting arrangements,
in advance, with the Administrator.
    (v) The owner or operator shall keep the written operation and
maintenance plan on record after it is developed to be made available
for inspection, upon request, by the Administrator for the life of the
affected source or until the source is no longer subject to the
provisions of this subpart. In addition, if the operation and
maintenance plan is revised, the owner or operator shall keep previous
(i.e., superseded) versions of the operation and maintenance plan on
record to be made available for inspection, upon request, by the
Administrator for a period of 5 years after each revision to the plan.
    (vi) To satisfy the requirements of paragraph (f)(3) of this
section, the owner or operator may use applicable standard operating
procedure (SOP) manuals, Occupational Safety and Health Administration
(OSHA) plans, or other existing plans, provided the alternative plans
meet the requirements of this section.
    (g) The standards in this section that apply to chromic acid baths
shall not be met by using a reducing agent to change the form of
chromium from hexavalent to trivalent.

Sec. 63.343  Compliance provisions.

    (a) Compliance dates. (1) The owner or operator of an existing
affected source shall comply with the emission limitations in
Sec. 63.342 as follows:
    (i) No later than 1 year after January 25, 1995, if the affected
source is a decorative chromium electroplating tank; and
    (ii) No later than 2 years after January 25, 1995, if the affected
source is a hard chromium electroplating tank or a chromium anodizing
tank.
    (2) The owner or operator of a new or reconstructed affected source
that has an initial startup after January 25, 1995, shall comply
immediately upon startup of the source. The owner or operator of a new
or reconstructed affected source that has an initial startup after
December 16, 1993 but before January 25, 1995, shall follow the
compliance schedule of Sec. 63.6(b) (3) and (4).

                           Table 1 to Sec. 63.342.--Summary of Work Practice Standards
----------------------------------------------------------------------------------------------------------------
    Control technique                      Work practice standards                            Frequency
----------------------------------------------------------------------------------------------------------------
Composite mesh-pad (CMP)   1. Visually inspect device to ensure there is proper     1. 1/quarter.
 system.                    drainage, no chronic acid buildup on the pads, and no
                            evidence of chemical attack on the structural
                            integrity of the device.
                           2. Visually inspect back portion of the mesh pad         2. 1/quarter.
                            closest to the fan to ensure there is no breakthrough
                            of chromic acid mist.
                           3. Visually inspect ductwork from tank to the control    3. 1/quarter.
                            device to ensure there are no leaks.
                           4. Perform washdown of the composite mesh-pads in        4. Per manufacturer.
                            accordance with manufacturers recommendations.
Packed-bed scrubber (PSB)  1. Visually inspect device to ensure there is proper     1. 1/quarter.
                            drainage, no chromic acid buildup on the packed beds,
                            and no evidence of chemical attack on the structural
                            integrity of the device.
                           2. Visually inspect back portion of the chevron blade    2. 1/quarter.
                            mist eliminator to ensure that it is dry and there is
                            no breakthrough of chromic acid mist.
                           3. Same as number 3 above..............................  3. 1/quarter.
[[Page 4967]]

                           4. Add fresh makeup water to the top of the packed bed   4. Whenever makeup is added.
                            <SUP>a,b.
PBS/CMP system...........  1. Same as for CMP system..............................  1. 1/quarter.
                           2. Same as for CMP system..............................  2. 1/quarter.
                           3. Same as for CMP system..............................  3. 1/quarter.
                           4. Same as for CMP system..............................  4. Per manufacturer.
Fiber-bed mist             1. Visually inspect fiber-bed unit and prefiltering      1. 1/quarter.
 eliminator<SUP>c.               device to ensure there is proper drainage, no chromic
                            acid buildup in the units, and no evidence of chemical
                            attack on the structural integrity of the devices.
                           2. Visually inspect ductwork from tank or tanks to the   2. 1/quarter.
                            control device to ensure there are no leaks.
                           3. Perform washdown of fiber elements in accordance      3. Per manufacturer.
                            with manufacturers recommendations.
Air pollution control      To be proposed by the source for approval by the         To be proposed by the source
 device (APCD) not listed   Administrator.                                           for approval by the
 in rule.                                                                            Administrator.

----------------------------------------------------------------------------------------------------------------
                                              Monitoring Equipment

----------------------------------------------------------------------------------------------------------------
Pitot tube...............  Backflush with water, or remove from the duct and rinse  1/quarter.
                            with fresh water. Replace in the duct and rotate 180
                            degrees to ensure that the same zero reading is
                            obtained. Check pitot tube ends for damage. Replace
                            pitot tube if cracked or fatigued.
Stalagmometer............  Follow manufacturers recommendations...................  ............................
----------------------------------------------------------------------------------------------------------------
<SUP>aIf greater than 50 percent of the scrubber water is drained (e.g., for maintenance purposes), makeup water may
  be added to the scrubber basin.
<SUP>bFor horizontal-flow scrubbers, top is defined as the section of the unit directly above the packing media such
  that the makeup water would flow perpendicular to the air flow through the packing. For vertical-flow units,
  the top is defined as the area downstream of the packing material such that the makeup water would flow
  countercurrent to the air flow through the unit.
<SUP>cWork practice standards for the control device installed upstream of the fiber-bed mist eliminator to prevent
  plugging do not apply as long as the work practice standards for the fiber-bed unit are followed.

    (3) The owner or operator of an existing area source that increases
actual or potential emissions of hazardous air pollutants such that the
area source becomes a major source must comply with the provisions for
existing major sources, including the reporting provisions of
Sec. 63.347(g), immediately upon becoming a major source.
    (4) The owner or operator of a new area source (i.e., an area
source for which construction or reconstruction was commenced after
December 16, 1993) that increases actual or potential emissions of
hazardous air pollutants such that the area source becomes a major
source must comply with the provisions for new major sources,
immediately upon becoming a major source.
    (5) An owner or operator of an existing hard chromium
electroplating tank or tanks located at a small, hard chromium
electroplating facility that increases its maximum cumulative potential
rectifier capacity, or its actual cumulative rectifier capacity, such
that the facility becomes a large, hard chromium electroplating
facility must comply with the requirements of Sec. 63.342(c)(1)(i) for
all hard chromium electroplating tanks at the facility no later than 1
year after the month in which monthly records required by
Secs. 63.342(c)(2) and 63.346(b)(12) show that the large designation is
met.
    (6) Request for an extension of compliance. An owner or operator of
an affected source or sources that requests an extension of compliance
shall do so in accordance with this paragraph and the applicable
paragraphs of Sec. 63.6(i). When the owner or operator is requesting
the extension for more than one affected source located at the
facility, then only one request may be submitted for all affected
sources at the facility.
    (i) The owner or operator of an existing affected source who is
unable to comply with a relevant standard under this subpart may
request that the Administrator (or a State, when the State has an
approved part 70 permit program and the source is required to obtain a
part 70 permit under that program, or a State, when the State has been
delegated the authority to implement and enforce the emission standard
for that source) grant an extension allowing the owner or operator up
to 1 additional year to comply with the standard for the affected
source. The owner or operator of an affected source who has requested
an extension of compliance under this paragraph and is otherwise
required to obtain a title V permit for the source shall apply for such
permit or apply to have the title V permit revised to incorporate the
conditions of the extension of compliance. The conditions of an
extension of compliance granted under this paragraph will be
incorporated into the owner or operator's title V permit for the
affected source(s) according to the provisions of 40 CFR part 70 or 40
CFR part 71, whichever is applicable.
    (ii) Any request under this paragraph for an extension of
compliance with a relevant standard shall be submitted in writing to
the appropriate authority not later than 6 months before the affected
source's compliance date as specified in this section.
    (7) An owner or operator of a decorative chromium electroplating
tank that uses a trivalent chromium bath that incorporates a wetting
agent, and that ceases using the trivalent chromium process, must
comply with the emission limitation now applicable to the tank within 1
year of switching bath operation.
    (b) Methods to demonstrate initial compliance. (1) Except as
provided in paragraphs (b)(2) and (b)(3) of this section, an owner or
operator of an affected source subject to the requirements of this
subpart is required to conduct an initial performance test as required
under Sec. 63.7, using the [[Page 4968]] procedures and test methods
listed in Sec. 63.7 and Sec. 63.344.
    (2) If the owner or operator of an affected source meets all of the
following criteria, an initial performance test is not required to be
conducted under this subpart:
    (i) The affected source is a decorative chromium electroplating
tank or a chromium anodizing tank; and
    (ii) A wetting agent is used in the plating or anodizing bath to
inhibit chromium emissions from the affected source; and
    (iii) The owner or operator complies with the applicable surface
tension limit of Sec. 63.342(d)(2) as demonstrated through the
continuous compliance monitoring required by paragraph (c)(5)(ii) of
this section.
    (3) If the affected source is a decorative chromium electroplating
tank using a trivalent chromium bath, and the owner or operator is
subject to the provisions of Sec. 63.342(e), an initial performance
test is not required to be conducted under this subpart.
    (c) Monitoring to demonstrate continuous compliance. The owner or
operator of an affected source subject to the emission limitations of
this subpart shall conduct monitoring according to the type of air
pollution control technique that is used to comply with the emission
limitation. The monitoring required to demonstrate continuous
compliance with the emission limitations is identified in this section
for the air pollution control techniques expected to be used by the
owners or operators of affected sources.
    (1) Composite mesh-pad systems. (i) During the initial performance
test, the owner or operator of an affected source, or a group of
affected sources under common control, complying with the emission
limitations in Sec. 63.342 through the use of a composite mesh-pad
system shall determine the outlet chromium concentration using the test
methods and procedures in Sec. 63.344(c), and shall establish as a
site-specific operating parameter the pressure drop across the system,
setting the value that corresponds to compliance with the applicable
emission limitation, using the procedures in Sec. 63.344(d)(5). An
owner or operator may conduct multiple performance tests to establish a
range of compliant pressure drop values, or may set as the compliant
value the average pressure drop measured over the three test runs of
one performance test and accept <plus-minus>1 inch of water column from
this value as the compliant range.
    (ii) On and after the date on which the initial performance test is
required to be completed under Sec. 63.7, the owner or operator of an
affected source, or group of affected sources under common control,
shall monitor and record the pressure drop across the composite mesh-
pad system once each day that any affected source is operating. To be
in compliance with the standards, the composite mesh-pad system shall
be operated within <plus-minus>1 inch of water column of the pressure
drop value established during the initial performance test, or shall be
operated within the range of compliant values for pressure drop
established during multiple performance tests.
    (2) Packed-bed scrubber systems. (i) During the initial performance
test, the owner or operator of an affected source, or group of affected
sources under common control, complying with the emission limitations
in Sec. 63.342 through the use of a packed-bed scrubber system shall
determine the outlet chromium concentration using the procedures in
Sec. 63.344(c), and shall establish as site-specific operating
parameters the pressure drop across the system and the velocity
pressure at the common inlet of the control device, setting the value
that corresponds to compliance with the applicable emission limitation
using the procedures in Sec. 63.344(d) (4) and (5). An owner or
operator may conduct multiple performance tests to establish a range of
compliant operating parameter values. Alternatively, the owner or
operator may set as the compliant value the average pressure drop and
inlet velocity pressure measured over the three test runs of one
performance test, and accept <plus-minus>1 inch of water column from
the pressure drop value and <plus-minus>10 percent from the velocity
pressure value as the compliant range.
    (ii) On and after the date on which the initial performance test is
required to be completed under Sec. 63.7, the owner or operator of an
affected source, or group of affected sources under common control,
shall monitor and record the velocity pressure at the inlet to the
packed-bed scrubber and the pressure drop across the scrubber system
once each day that any affected source is operating. To be in
compliance with the standards, the scrubber system shall be operated
within <plus-minus>10 percent of the velocity pressure value
established during the initial performance test, and within
<plus-minus>1 inch of water column of the pressure drop value
established during the initial performance test, or within the range of
compliant operating parameter values established during multiple
performance tests.
    (3) Packed-bed scrubber/composite mesh-pad system. The owner or
operator of an affected source, or group of affected sources under
common control, that uses a packed-bed scrubber in conjunction with a
composite mesh-pad system to meet the emission limitations of
Sec. 63.342 shall comply with the monitoring requirements for composite
mesh-pad systems as identified in paragraph (c)(1) of this section.
    (4) Fiber-bed mist eliminator. (i) During the initial performance
test, the owner or operator of an affected source, or group of affected
sources under common control, complying with the emission limitations
in Sec. 63.342 through the use of a fiber-bed mist eliminator shall
determine the outlet chromium concentration using the procedures in
Sec. 63.344(c), and shall establish as a site-specific operating
parameter the pressure drop across the fiber-bed mist eliminator and
the pressure drop across the control device installed upstream of the
fiber bed to prevent plugging, setting the value that corresponds to
compliance with the applicable emission limitation using the procedures
in Sec. 63.344(d)(5). An owner or operator may conduct multiple
performance tests to establish a range of compliant pressure drop
values, or may set as the compliant value the average pressure drop
measured over the three test runs of one performance test and accept
<plus-minus>1 inch of water column from this value as the compliant
range.
    (ii) On and after the date on which the initial performance test is
required to be completed under Sec. 63.7, the owner or operator of an
affected source, or group of affected sources under common control,
shall monitor and record the pressure drop across the fiber-bed mist
eliminator, and the control device installed upstream of the fiber bed
to prevent plugging, once each day that any affected source is
operating. To be in compliance with the standards, the fiber-bed mist
eliminator and the upstream control device shall be operated within
<plus-minus>1 inch of water column of the pressure drop value
established during the initial performance test, or shall be operated
within the range of compliant values for pressure drop established
during multiple performance tests.
    (5) Wetting agent-type or combination wetting agent-type/foam
blanket fume suppressants. (i) During the initial performance test, the
owner or operator of an affected source complying with the emission
limitations in Sec. 63.342 through the use of a wetting agent in the
electroplating or anodizing bath shall determine the outlet chromium
concentration using the procedures in Sec. 63.344(c). The owner or
operator shall establish as the site-specific operating parameter the
surface tension of the bath using Method 306B, appendix A of
[[Page 4969]] this part, setting the maximum value that corresponds to
compliance with the applicable emission limitation. In lieu of
establishing the maximum surface tension during the performance test,
the owner or operator may accept 45 dynes/cm as the maximum surface
tension value that corresponds to compliance with the applicable
emission limitation. However, the owner or operator is exempt from
conducting a performance test only if the criteria of paragraph (b)(2)
of this section are met.
    (ii) On and after the date on which the initial performance test is
required to be completed under Sec. 63.7, the owner or operator of an
affected source shall monitor the surface tension of the electroplating
or anodizing bath. Operation of the affected source at a surface
tension greater than the value established during the performance test,
or greater than 45 dynes/cm if the owner or operator is using this
value in accordance with paragraph (c)(5)(i) of this section, shall
constitute noncompliance with the standards. The surface tension shall
be monitored according to the following schedule:
    (A) The surface tension shall be measured once every 4 hours during
operation of the tank with a stalagmometer or a tensiometer as
specified in Method 306B, appendix A of this part.
    (B) The time between monitoring can be increased if there have been
no exceedances. The surface tension shall be measured once every 4
hours of tank operation for the first 40 hours of tank operation after
the compliance date. Once there are no exceedances during 40 hours of
tank operation, surface tension measurement may be conducted once every
8 hours of tank operation. Once there are no exceedances during 40
hours of tank operation, surface tension measurement may be conducted
once every 40 hours of tank operation on an ongoing basis, until an
exceedance occurs. The minimum frequency of monitoring allowed by this
subpart is once every 40 hours of tank operation.
    (C) Once an exceedance occurs as indicated through surface tension
monitoring, the original monitoring schedule of once every 4 hours must
be resumed. A subsequent decrease in frequency shall follow the
schedule laid out in paragraph (c)(5)(ii)(B) of this section. For
example, if an owner or operator had been monitoring an affected source
once every 40 hours and an exceedance occurs, subsequent monitoring
would take place once every 4 hours of tank operation. Once an
exceedance does not occur for 40 hours of tank operation, monitoring
can occur once every 8 hours of tank operation. Once an exceedance does
not occur for 40 hours of tank operation on this schedule, monitoring
can occur once every 40 hours of tank operation.
    (iii) Once a bath solution is drained from the affected tank and a
new solution added, the original monitoring schedule of once every 4
hours must be resumed, with a decrease in monitoring frequency allowed
following the procedures of paragraphs (c)(5)(ii) (B) and (C) of this
section.
    (6) Foam blanket-type fume suppressants. (i) During the initial
performance test, the owner or operator of an affected source complying
with the emission limitations in Sec. 63.342 through the use of a foam
blanket in the electroplating or anodizing bath shall determine the
outlet chromium concentration using the procedures in Sec. 63.344(c),
and shall establish as the site-specific operating parameter the
thickness of the foam blanket, setting the minimum thickness that
corresponds to compliance with the applicable emission limitation. In
lieu of establishing the minimum foam blanket thickness during the
performance test, the owner or operator may accept 2.54 centimeters (1
inch) as the minimum foam blanket thickness that corresponds to
compliance with the applicable emission limitation. All foam blanket
measurements must be taken in close proximity to the workpiece or
cathode area in the plating tank(s).
    (ii) On and after the date on which the initial performance test is
required to be completed under Sec. 63.7, the owner or operator of an
affected source shall monitor the foam blanket thickness of the
electroplating or anodizing bath. Operation of the affected source at a
foam blanket thickness less than the value established during the
performance test, or less than 2.54 cm (1 inch) if the owner or
operator is using this value in accordance with paragraph (c)(6)(i) of
this section, shall constitute noncompliance with the standards. The
foam blanket thickness shall be measured according to the following
schedule:
    (A) The foam blanket thickness shall be measured once every 1 hour
of tank operation.
    (B) The time between monitoring can be increased if there have been
no exceedances. The foam blanket thickness shall be measured once every
hour of tank operation for the first 40 hours of tank operation after
the compliance date. Once there are no exceedances for 40 hours of tank
operation, foam blanket thickness measurement may be conducted once
every 4 hours of tank operation. Once there are no exceedances during
40 hours of tank operation, foam blanket thickness measurement may be
conducted once every 8 hours of tank operation on an ongoing basis,
until an exceedance occurs. The minimum frequency of monitoring allowed
by this subpart is once per 8 hours of tank operation.
    (C) Once an exceedance occurs as indicated through foam blanket
thickness monitoring, the original monitoring schedule of once every
hour must be resumed. A subsequent decrease in frequency shall follow
the schedule laid out in paragraph (c)(6)(ii)(B) of this section. For
example, if an owner or operator had been monitoring an affected source
once every 8 hours and an exceedance occurs, subsequent monitoring
would take place once every hour of tank operation. Once an exceedance
does not occur for 40 hours of tank operation, monitoring can occur
once every 4 hours of tank operation. Once an exceedance does not occur
for 40 hours of tank operation on this schedule, monitoring can occur
once every 8 hours of tank operation.
    (iii) Once a bath solution is drained from the affected tank and a
new solution added, the original monitoring schedule of once every hour
must be resumed, with a decrease in monitoring frequency allowed
following the procedures of paragraphs (c)(6)(ii) (B) and (C) of this
section.
    (7) Fume suppressant/add-on control device. (i) If the owner or
operator of an affected source uses both a fume suppressant and add-on
control device and both are needed to comply with the applicable
emission limit, monitoring requirements as identified in paragraphs (c)
(1) through (6) of this section, and the work practice standards of
Table 1 of Sec. 63.342, apply for each of the control techniques used.
    (ii) If the owner or operator of an affected source uses both a
fume suppressant and add-on control device, but only one of these
techniques is needed to comply with the applicable emission limit,
monitoring requirements as identified in paragraphs (c) (1) through (6)
of this section, and work practice standards of Table 1 of Sec. 63.342,
apply only for the control technique used to achieve compliance.
    (8) Use of an alternative monitoring method. (i) Requests and
approvals of alternative monitoring methods shall be considered in
accordance with Sec. 63.8(f)(1), (f)(3), (f)(4), and (f)(5).
    (ii) After receipt and consideration of an application for an
alternative monitoring method, the Administrator may approve
alternatives to any [[Page 4970]] monitoring methods or procedures of
this subpart including, but not limited to, the following:
    (A) Alternative monitoring requirements when installation or use of
monitoring devices specified in this subpart would not provide accurate
measurements due to interferences caused by substances within the
effluent gases; or
    (B) Alternative locations for installing monitoring devices when
the owner or operator can demonstrate that installation at alternate
locations will enable accurate and representative measurements.
    (d) An owner or operator who uses an air pollution control device
not listed in this section shall submit a description of the device,
test results collected in accordance with Sec. 63.344(c) verifying the
performance of the device for reducing chromium emissions to the
atmosphere to the level required by this subpart, a copy of the
operation and maintenance plan referenced in Sec. 63.342(f) including
proposed work practice standards, and appropriate operating parameters
that will be monitored to establish continuous compliance with the
standards. The monitoring plan submitted identifying the continuous
compliance monitoring is subject to the Administrator's approval.

Sec. 63.344  Performance test requirements and test methods.

    (a) Performance test requirements. Performance tests shall be
conducted using the test methods and procedures in this section and
Sec. 63.7. Performance test results shall be documented in complete
test reports that contain the information required by paragraphs (a)(1)
through (a)(9) of this section. The test plan to be followed shall be
made available to the Administrator prior to the testing, if requested.
    (1) A brief process description;
    (2) Sampling location description(s);
    (3) A description of sampling and analytical procedures and any
modifications to standard procedures;
    (4) Test results;
    (5) Quality assurance procedures and results;
    (6) Records of operating conditions during the test, preparation of
standards, and calibration procedures;
    (7) Raw data sheets for field sampling and field and laboratory
analyses;
    (8) Documentation of calculations; and
    (9) Any other information required by the test method.
    (b)(1) If the owner or operator of an affected source conducts
performance testing at startup to obtain an operating permit in the
State in which the affected source is located, the results of such
testing may be used to demonstrate compliance with this subpart if:
    (i) The test methods and procedures identified in paragraph (c) of
this section were used during the performance test;
    (ii) The performance test was conducted under representative
operating conditions for the source;
    (iii) The performance test report contains the elements required by
paragraph (a) of this section; and
    (iv) The owner or operator of the affected source for which the
performance test was conducted has sufficient data to establish the
operating parameter value(s) that correspond to compliance with the
standards, as required for continuous compliance monitoring under
Sec. 63.343(c).
    (2) The results of tests conducted prior to December 1991 in which
Method 306A, appendix A of this part, was used to demonstrate the
performance of a control technique are not acceptable.
    (c) Test methods. Each owner or operator subject to the provisions
of this subpart and required by Sec. 63.343(b) to conduct an initial
performance test shall use the test methods identified in this section
to demonstrate compliance with the standards in Sec. 63.342.
    (1) Method 306 or Method 306A, ``Determination of Chromium
Emissions From Decorative and Hard Chromium Electroplating and
Anodizing Operations,'' appendix A of this part shall be used to
determine the chromium concentration from hard or decorative chromium
electroplating tanks or chromium anodizing tanks. The sampling time and
sample volume for each run of Methods 306 and 306A, appendix A of this
part shall be at least 120 minutes and 1.70 dscm (60 dscf),
respectively. Methods 306 and 306A, appendix A of this part allow the
measurement of either total chromium or hexavalent chromium emissions.
For the purposes of this standard, sources using chromic acid baths can
demonstrate compliance with the emission limits of Sec. 63.342 by
measuring either total chromium or hexavalent chromium. Hence, the
hexavalent chromium concentration measured by these methods is equal to
the total chromium concentration for the affected operations.
    (2) The California Air Resources Board (CARB) Method 425 (which is
available by contacting the California Air Resources Board, 1102 Q
Street, Sacramento, California 95814) may be used to determine the
chromium concentration from hard and decorative chromium electroplating
tanks and chromium anodizing tanks if the following conditions are met:
    (i) If a colorimetric analysis method is used, the sampling time
and volume shall be sufficient to result in 33 to 66 micrograms of
catch in the sampling train.
    (ii) If Atomic Absorption Graphite Furnace (AAGF) or Ion
Chromatography with a Post-column Reactor (ICPCR) analyses were used,
the sampling time and volume should be sufficient to result in a sample
catch that is 5 to 10 times the minimum detection limit of the
analytical method (i.e., 1.0 microgram per liter of sample for AAGF and
0.5 microgram per liter of sample for ICPCR).
    (iii) In the case of either paragraph (c)(2) (i) or (ii) of this
section, a minimum of 3 separate runs must be conducted. The other
requirements of Sec. 63.7 that apply to affected sources, as indicated
in Table 1 of this subpart, must also be met.
    (3) Method 306B, ``Surface Tension Measurement and Recordkeeping
for Tanks Used at Decorative Chromium Electroplating and Anodizing
Facilities,'' appendix A of this part shall be used to measure the
surface tension of electroplating and anodizing baths.
    (4) Alternate test methods may also be used if the method has been
validated using Method 301, appendix A of this part and if approved by
the Administrator. Procedures for requesting and obtaining approval are
contained in Sec. 63.7(f).
    (d) Establishing site-specific operating parameter values. (1) Each
owner or operator required to establish site-specific operating
parameters shall follow the procedures in this section.
    (2) All monitoring equipment shall be installed such that
representative measurements of emissions or process parameters from the
affected source are obtained. For monitoring equipment purchased from a
vendor, verification of the operational status of the monitoring
equipment shall include execution of the manufacturer's written
specifications or recommendations for installation, operation, and
calibration of the system.
    (i) Specifications for differential pressure measurement devices
used to measure velocity pressure shall be in accordance with section
2.2 of Method 2 (40 CFR part 60, appendix A).
    (ii) Specification for differential pressure measurement devices
used to measure pressure drop across a control system shall be in
accordance with manufacturer's accuracy specifications.
    (3) The surface tension of electroplating and anodizing baths shall
[[Page 4971]] be measured using Method 306B, ``Surface Tension
Measurement and Recordkeeping for Tanks used at Decorative Chromium
Electroplating and Anodizing Facilities,'' appendix A of this part.
This method should also be followed when wetting agent type or
combination wetting agent/foam blanket type fume suppressants are used
to control chromium emissions from a hard chromium electroplating tank
and surface tension measurement is conducted to demonstrate continuous
compliance.
    (4) The owner or operator of a source required to measure the
velocity pressure at the inlet to an add-on air pollution control
device in accordance with Sec. 63.343(c)(2), shall establish the site-
specific velocity pressure as follows:
    (i) Locate a velocity traverse port in a section of straight duct
that connects the hooding on the plating tank or tanks with the control
device. The port shall be located as close to the control system as
possible, and shall be placed a minimum of 2 duct diameters downstream
and 0.5 diameter upstream of any flow disturbance such as a bend,
expansion, or contraction (see Method 1, 40 CFR part 60, appendix A).
If 2.5 diameters of straight duct work does not exist, locate the port
0.8 of the duct diameter downstream and 0.2 of the duct diameter
upstream from any flow disturbance.
    (ii) A 12-point velocity traverse of the duct to the control device
shall be conducted along a single axis according to Method 2 (40 CFR
part 60, appendix A) using an S-type pitot tube; measurement of the
barometric pressure and duct temperature at each traverse point is not
required, but is suggested. Mark the S-type pitot tube as specified in
Method 1 (40 CFR part 60, appendix A) with 12 points. Measure the
velocity pressure (<greek-D>p) values for the velocity points and
record. Determine the square root of the individual velocity point
<greek-D>p values and average. The point with the square root value
that comes closest to the average square root value is the point of
average velocity. The <greek-D>p value measured for this point during
the performance test will be used as the reference for future
monitoring.
    (5) The owner or operator of a source required to measure the
pressure drop across the add-on air pollution control device in
accordance with Sec. 63.343(c) (1) through (4) may establish the
pressure drop in accordance with the following guidelines:
    (i) Pressure taps shall be installed at any of the following
locations:
    (A) At the inlet and outlet of the control system. The inlet tap
should be installed in the ductwork just prior to the control device
and the corresponding outlet pressure tap should be installed on the
outlet side of the control device prior to the blower or on the
downstream side of the blower;
    (B) On each side of the packed bed within the control system or on
each side of each mesh pad within the control system; or
    (C) On the front side of the first mesh pad and back side of the
last mesh pad within the control system.
    (ii) Pressure taps shall be sited at locations that are:
    (A) Free from pluggage as possible and away from any flow
disturbances such as cyclonic demisters.
    (B) Situated such that no air infiltration at measurement site will
occur that could bias the measurement.
    (iii) Pressure taps shall be constructed of either polyethylene,
polybutylene, or other nonreactive materials.
    (iv) Nonreactive plastic tubing shall be used to connect the
pressure taps to the device used to measure pressure drop.
    (v) Any of the following pressure gauges can be used to monitor
pressure drop: a magnehelic gauge, an inclined manometer, or a ``U''
tube manometer.
    (vi) Prior to connecting any pressure lines to the pressure
gauge(s), each gauge should be zeroed. No calibration of the pressure
gauges is required.
    (e) Special compliance provisions for multiple sources controlled
by a common add-on air pollution control device.
    (1) This section identifies procedures for measuring the outlet
chromium concentration from an add-on air pollution control device that
is used to control multiple sources that may or may not include sources
not affected by this subpart.
    (2) When multiple affected sources performing the same type of
operation (e.g., all are performing hard chromium electroplating), and
subject to the same emission limitation, are controlled with an add-on
air pollution control device that is not controlling emissions from any
other type of affected operation or from any nonaffected sources, the
applicable emission limitation identified in Sec. 63.342 must be met at
the outlet of the add-on air pollution control device.
    (3) When multiple affected sources performing the same type of
operation and subject to the same emission limitation are controlled
with a common add-on air pollution control device that is also
controlling emissions from sources not affected by these standards, the
following procedures should be followed to determine compliance with
the applicable emission limitation in Sec. 63.342:
    (i) Calculate the cross-sectional area of each inlet duct (i.e.,
uptakes from each hood) including those not affected by the standard.
    (ii) Determine the total sample time per test run by dividing the
total inlet area from all tanks connected to the control system by the
total inlet area for all ducts associated with affected sources, and
then multiply this number by 2 hours. The calculated time is the
minimum sample time required per test run.
    (iii) Perform Method 306 testing and calculate an outlet mass
emission rate.
    (iv) Determine the total ventilation rate from the affected sources
by using equation 1:
[GRAPHIC][TIFF OMITTED]TR25JA95.000

where VR<INF>tot is the average total ventilation rate in dscm/min for
the three test runs as determined at the outlet by means of the Method
306 testing; IDA<INF>i is the total inlet area for all ducts associated
with affected sources; IA<INF>total is the sum of all inlet duct areas
from both affected and nonaffected sources; and VR<INF>inlet is the
total ventilation rate from all inlet ducts associated with affected
sources.
    (v) Establish the allowable mass emission rate of the system
(AMR<INF>sys) in milligrams of total chromium per hour (mg/hr) using
equation 2:
[GRAPHIC][TIFF OMITTED]TR25JA95.001

where <greek-S> VR<INF>inlet is the total ventilation rate in dscm/min
from the affected sources, and EL is the applicable emission limitation
from Sec. 63.342 in mg/dscm. The allowable mass emission rate
(AMR<INF>sys) calculated from equation 2 should be equal to or less
than the outlet three-run average mass emission rate determined from
Method 306 testing in order for the source to be in compliance with the
standard. [[Page 4972]]
    (4) When multiple affected sources performing different types of
operations (e.g., hard chromium electroplating, decorative chromium
electroplating, or chromium anodizing) are controlled by a common add-
on air pollution control device that may or may not also be controlling
emissions from sources not affected by these standards, or if the
affected sources controlled by the common add-on air pollution control
device perform the same operation but are subject to different emission
limitations (e.g., because one is a new hard chromium plating tank and
one is an existing small, hard chromium plating tank), the following
procedures should be followed to determine compliance with the
applicable emission limitation in Sec. 63.342:
    (i) Follow the steps outlined in paragraphs (e)(3)(i) through
(e)(3)(iii) of this section.
    (ii) Determine the total ventilation rate for each type of affected
source using equation 3:
[GRAPHIC][TIFF OMITTED]TR25JA95.002

where VR<INF>tot is the average total ventilation rate in dscm/min for
the three test runs as determined at the outlet by means of the Method
306 testing; IDA<INF>i,a is the total inlet duct area for all ducts
conveying chromic acid from each type of affected source performing the
same operation, or each type of affected source subject to the same
emission limitation; IA<INF>total is the sum of all duct areas from
both affected and nonaffected sources; and VR<INF>inlet,a is the total
ventilation rate from all inlet ducts conveying chromic acid from each
type of affected source performing the same operation, or each type of
affected source subject to the same emission limitation.
    (iii) Establish the allowable mass emission rate in mg/hr for each
type of affected source that is controlled by the add-on air pollution
control device using equation 4, 5, 6, or 7 as appropriate:

VR<INF>hc1  x  EL<INF>hc1  x  60 minutes/hour = AMR<INF>hc1     (4)

VR<INF>hc2  x  EL<INF>hc2  x  60 minutes/hour = AMR<INF>hc2    (5)

 VR<INF>dc  x  EL<INF>dc  x  60 minutes/hour = AMR<INF>dc    (6)

 VR<INF>ca  x  EL<INF>ca  x  60 minutes/hour = AMR<INF>ca    (7)

where ``hc'' applies to the total of ventilation rates for all hard
chromium electroplating tanks subject to the same emission limitation,
``dc'' applies to the total of ventilation rates for the decorative
chromium electroplating tanks, ``ca'' applies to the total of
ventilation rates for the chromium anodizing tanks, and EL is the
applicable emission limitation from Sec. 63.342 in mg/dscm. There are
two equations for hard chromium electroplating tanks because different
emission limitations may apply (e.g., a new tank versus an existing,
small tank).
    (iv) Establish the allowable mass emission rate (AMR) in mg/hr for
the system using equation 8, including each type of affected source as
appropriate:

 AMR<INF>hc1 + AMR<INF>hc2 + AMR<INF>dc + AMR<INF>ca = AMR<INF>sys
(8)

The allowable mass emission rate calculated from equation 8 should be
equal to or less than the outlet three-run average mass emission rate
determined from Method 306 testing in order for the source to be in
compliance with the standards.
     (5) Each owner or operator that uses the special compliance
provisions of this paragraph to demonstrate compliance with the
emission limitations of Sec. 63.342 shall submit the measurements and
calculations to support these compliance methods with the notification
of compliance status required by Sec. 63.347(e).
    (6) Each owner or operator that uses the special compliance
provisions of this section to demonstrate compliance with the emission
limitations of Sec. 63.342 shall repeat these procedures if a tank is
added or removed from the control system regardless of whether that
tank is a nonaffected source. If the new nonaffected tank replaces an
existing nonaffected tank of the same size and is connected to the
control system through the same size inlet duct then this procedure
does not have to be repeated.

Sec. 63.345  Provisions for new and reconstructed sources.

    (a) This section identifies the preconstruction review requirements
for new and reconstructed affected sources that are subject to, or
become subject to, this subpart.
    (b) New or reconstructed affected sources. The owner or operator of
a new or reconstructed affected source is subject to Sec. 63.5(a),
(b)(1), (b)(5), (b)(6), and (f)(1), as well as the provisions of this
paragraph.
    (1) After January 25, 1995, whether or not an approved permit
program is effective in the State in which an affected source is (or
would be) located, no person may construct a new affected source or
reconstruct an affected source subject to this subpart, or reconstruct
a source such that it becomes an affected source subject to this
subpart, without submitting a notification of construction or
reconstruction to the Administrator. The notification shall contain the
information identified in paragraphs (b) (2) and (3) of this section,
as appropriate.
    (2) The notification of construction or reconstruction required
under paragraph (b)(1) of this section shall include:
    (i) The owner or operator's name, title, and address;
    (ii) The address (i.e., physical location) or proposed address of
the affected source if different from the owner's or operator's;
    (iii) A notification of intention to construct a new affected
source or make any physical or operational changes to an affected
source that may meet or has been determined to meet the criteria for a
reconstruction as defined in Sec. 63.2;
    (iv) An identification of subpart N of this part as the basis for
the notification;
    (v) The expected commencement and completion dates of the
construction or reconstruction;
    (vi) The anticipated date of (initial) startup of the affected
source;
    (vii) The type of process operation to be performed (hard or
decorative chromium electroplating, or chromium anodizing);
    (viii) A description of the air pollution control technique to be
used to control emissions from the affected source, such as preliminary
design drawings and design capacity if an add-on air pollution control
device is used; and
    (ix) An estimate of emissions from the source based on engineering
calculations and vendor information on control device efficiency,
expressed in units consistent with the emission limits of this subpart.
Calculations of emission estimates should be in sufficient detail to
permit assessment of the validity of the calculations.
    (3) If a reconstruction is to occur, the notification required
under paragraph (b)(1) of this section shall include the following in
addition to the information required in paragraph (b)(2) of this
section:
    (i) A brief description of the affected source and the components
to be replaced;
    (ii) A brief description of the present and proposed emission
control technique, including the information required by paragraphs
(b)(2) (viii) and (ix) of this section;
    (iii) An estimate of the fixed capital cost of the replacements and
of constructing a comparable entirely new source;
    (iv) The estimated life of the affected source after the
replacements; and
    (v) A discussion of any economic or technical limitations the
source may [[Page 4973]] have in complying with relevant standards or
other requirements after the proposed replacements. The discussion
shall be sufficiently detailed to demonstrate to the Administrator's
satisfaction that the technical or economic limitations affect the
source's ability to comply with the relevant standard and how they do
so.
    (vi) If in the notification of reconstruction, the owner or
operator designates the affected source as a reconstructed source and
declares that there are no economic or technical limitations to prevent
the source from complying with all relevant standards or requirements,
the owner or operator need not submit the information required in
paragraphs (b)(3) (iii) through (v) of this section.
    (4) The owner or operator of a new or reconstructed affected source
that submits a notification in accordance with paragraphs (b) (1)
through (3) of this section is not subject to approval by the
Administrator. Construction or reconstruction is subject only to
notification and can begin upon submission of a complete notification.
    (5) Submittal timeframes. After January 25, 1995, whether or not an
approved permit program is effective in the State in which an affected
source is (or would be) located, an owner or operator of a new or
reconstructed affected source shall submit the notification of
construction or reconstruction required by paragraph (b)(1) of this
section according to the following schedule:
    (i) If construction or reconstruction commences after January 25,
1995, the notification shall be submitted as soon as practicable before
the construction or reconstruction is planned to commence.
    (ii) If the construction or reconstruction had commenced and
initial startup had not occurred before January 25, 1995, the
notification shall be submitted as soon as practicable before startup
but no later than 60 days after January 25, 1995.

Sec. 63.346  Recordkeeping requirements.

    (a) The owner or operator of each affected source subject to these
standards shall fulfill all recordkeeping requirements outlined in this
section and in the General Provisions to 40 CFR part 63, according to
the applicability of subpart A of this part as identified in Table 1 of
this subpart.
    (b) The owner or operator of an affected source subject to the
provisions of this subpart shall maintain the following records for
such source:
    (1) Inspection records for the add-on air pollution control device,
if such a device is used, and monitoring equipment, to document that
the inspection and maintenance required by the work practice standards
of Sec. 63.342(f) and Table 1 of Sec. 63.342 have taken place. The
record can take the form of a checklist and should identify the device
inspected, the date of inspection, a brief description of the working
condition of the device during the inspection, and any actions taken to
correct deficiencies found during the inspection.
    (2) Records of all maintenance performed on the affected source,
the add-on air pollution control device, and monitoring equipment;
    (3) Records of the occurrence, duration, and cause (if known) of
each malfunction of process, add-on air pollution control, and
monitoring equipment;
    (4) Records of actions taken during periods of malfunction when
such actions are inconsistent with the operation and maintenance plan;
    (5) Other records, which may take the form of checklists, necessary
to demonstrate consistency with the provisions of the operation and
maintenance plan required by Sec. 63.342(f)(3);
    (6) Test reports documenting results of all performance tests;
    (7) All measurements as may be necessary to determine the
conditions of performance tests, including measurements necessary to
determine compliance with the special compliance procedures of
Sec. 63.344(e);
    (8) Records of monitoring data required by Sec. 63.343(c) that are
used to demonstrate compliance with the standard including the date and
time the data are collected;
    (9) The specific identification (i.e., the date and time of
commencement and completion) of each period of excess emissions, as
indicated by monitoring data, that occurs during malfunction of the
process, add-on air pollution control, or monitoring equipment;
    (10) The specific identification (i.e., the date and time of
commencement and completion) of each period of excess emissions, as
indicated by monitoring data, that occurs during periods other than
malfunction of the process, add-on air pollution control, or monitoring
equipment;
    (11) The total process operating time of the affected source during
the reporting period;
    (12) Records of the actual cumulative rectifier capacity of hard
chromium electroplating tanks at a facility expended during each month
of the reporting period, and the total capacity expended to date for a
reporting period, if the owner or operator is using the actual
cumulative rectifier capacity to determine facility size in accordance
with Sec. 63.342(c)(2);
    (13) For sources using fume suppressants to comply with the
standards, records of the date and time that fume suppressants are
added to the electroplating or anodizing bath;
    (14) For sources complying with Sec. 63.342(e), records of the bath
components purchased, with the wetting agent clearly identified as a
bath constituent contained in one of the components;
    (15) Any information demonstrating whether a source is meeting the
requirements for a waiver of recordkeeping or reporting requirements,
if the source has been granted a waiver under Sec. 63.10(f); and
    (16) All documentation supporting the notifications and reports
required by Sec. 63.9, Sec. 63.10, and Sec. 63.347.
    (c) All records shall be maintained for a period of 5 years in
accordance with Sec. 63.10(b)(1).

Sec. 63.347  Reporting requirements.

    (a) The owner or operator of each affected source subject to these
standards shall fulfill all reporting requirements outlined in this
section and in the General Provisions to 40 CFR part 63, according to
the applicability of subpart A as identified in Table 1 of this
subpart. These reports shall be made to the Administrator at the
appropriate address as identified in Sec. 63.13 or to the delegated
State authority.
    (1) Reports required by subpart A of this part and this section may
be sent by U.S. mail, fax, or by another courier.
    (i) Submittals sent by U.S. mail shall be postmarked on or before
the specified date.
    (ii) Submittals sent by other methods shall be received by the
Administrator on or before the specified date.
    (2) If acceptable to both the Administrator and the owner or
operator of an affected source, reports may be submitted on electronic
media.
    (b) The reporting requirements of this section apply to the owner
or operator of an affected source when such source becomes subject to
the provisions of this subpart.
    (c) Initial notifications. (1) The owner or operator of an affected
source that has an initial startup before January 25, 1995, shall
notify the Administrator in writing that the source is subject to this
subpart. The notification shall be submitted no later than 180 calendar
days after January 25, 1995, and shall contain the following
information:
    (i) The name, title, and address of the owner or operator;
    (ii) The address (i.e., physical location) of each affected source;
[[Page 4974]]
    (iii) A statement that subpart N of this part is the basis for this
notification;
    (iv) Identification of the applicable emission limitation and
compliance date for each affected source;
    (v) A brief description of each affected source, including the type
of process operation performed;
     (vi) For sources performing hard chromium electroplating, the
maximum potential cumulative potential rectifier capacity;
    (vii) For sources performing hard chromium electroplating, a
statement of whether the affected source(s) is located at a small or a
large, hard chromium electroplating facility and whether this will be
demonstrated through actual or maximum potential cumulative rectifier
capacity;
    (viii) For sources performing hard chromium electroplating tanks, a
statement of whether the owner or operator of an affected source(s)
will limit the maximum potential cumulative rectifier capacity in
accordance with Sec. 63.342(c)(2) such that the hard chromium
electroplating facility is considered small; and
    (ix) A statement of whether the affected source is located at a
major source or an area source as defined in Sec. 63.2.
    (2) The owner or operator of a new or reconstructed affected source
that has an initial startup after January 25, 1995 shall submit an
initial notification (in addition to the notification of construction
or reconstruction required by Sec. 63.345(b) as follows:
    (i) A notification of the date when construction or reconstruction
was commenced, shall be submitted simultaneously with the notification
of construction or reconstruction, if construction or reconstruction
was commenced before January 25, 1995;
    (ii) A notification of the date when construction or reconstruction
was commenced, shall be submitted no later than 30 calendar days after
such date, if construction or reconstruction was commenced after
January 25, 1995; and
    (iii) A notification of the actual date of startup of the source
shall be submitted within 30 calendar days after such date.
    (d) Notification of performance test. (1) The owner or operator of
an affected source shall notify the Administrator in writing of his or
her intention to conduct a performance test at least 60 calendar days
before the test is scheduled to begin to allow the Administrator to
have an observer present during the test. Observation of the
performance test by the Administrator is optional.
    (2) In the event the owner or operator is unable to conduct the
performance test as scheduled, the provisions of Sec. 63.7(b)(2) apply.
    (e) Notification of compliance status. (1) A notification of
compliance status is required each time that an affected source becomes
subject to the requirements of this subpart.
    (2) Before a title V permit has been issued to the owner or
operator of an affected source, each time a notification of compliance
status is required under this part, the owner or operator of an
affected source shall submit to the Administrator a notification of
compliance status, signed by the responsible official (as defined in
Sec. 63.2) who shall certify its accuracy, attesting to whether the
affected source has complied with this subpart. After a title V permit
has been issued to the owner or operator of an affected source, the
notification of compliance status shall be submitted to the appropriate
permitting authority. The notification shall list for each affected
source:
    (i) The applicable emission limitation and the methods that were
used to determine compliance with this limitation;
    (ii) If a performance test is required by this subpart, the test
report documenting the results of the performance test, which contains
the elements required by Sec. 63.344(a), including measurements and
calculations to support the special compliance provisions of
Sec. 63.344(e) if these are being followed;
    (iii) The type and quantity of hazardous air pollutants emitted by
the source reported in mg/dscm or mg/hr if the source is using the
special provisions of Sec. 63.344(e) to comply with the standards. (If
the owner or operator is subject to the construction and reconstruction
provisions of Sec. 63.345 and had previously submitted emission
estimates, the owner or operator shall state that this report corrects
or verifies the previous estimate.) For sources not required to conduct
a performance test in accordance with Sec. 63.343(b), the surface
tension measurement may fulfill this requirement;
    (iv) For each monitored parameter for which a compliant value is to
be established under Sec. 63.343(c), the specific operating parameter
value, or range of values, that corresponds to compliance with the
applicable emission limit;
    (v) The methods that will be used to determine continuous
compliance, including a description of monitoring and reporting
requirements, if methods differ from those identified in this subpart;
    (vi) A description of the air pollution control technique for each
emission point;
    (vii) A statement that the owner or operator has completed and has
on file the operation and maintenance plan as required by the work
practice standards in Sec. 63.342(f);
    (viii) If the owner or operator is determining facility size based
on actual cumulative rectifier capacity in accordance with
Sec. 63.342(c)(2), records to support that the facility is small. For
existing sources, records from any 12-month period preceding the
compliance date shall be used or a description of how operations will
change to meet a small designation shall be provided. For new sources,
records of projected rectifier capacity for the first 12-month period
of tank operation shall be used;
    (ix) A statement by the owner or operator of the affected source as
to whether the source has complied with the provisions of this subpart.
    (3) For sources required to conduct a performance test by
Sec. 63.343(b), the notification of compliance status shall be
submitted to the Administrator no later than 90 calendar days following
completion of the compliance demonstration required by Sec. 63.7 and
Sec. 63.343(b).
    (4) For sources that are not required to complete a performance
test in accordance with Sec. 63.343(b), the notification of compliance
status shall be submitted to the Administrator no later than 30 days
after the compliance date specified in Sec. 63.343(a).
    (f) Reports of performance test results. (1) Before a title V
permit has been issued to the owner or operator of an affected source,
the owner or operator shall report to the Administrator the results of
any performance test conducted as required by Sec. 63.7 or
Sec. 63.343(b). After a title V permit has been issued to the owner or
operator of an affected source, the owner or operator should report
performance test results to the appropriate permitting authority.
    (2) Reports of performance test results shall be submitted no later
than 90 days following the completion of the performance test, and
shall be submitted as part of the notification of compliance status
required by paragraph (e) of this section.
    (g) Ongoing compliance status reports for major sources. (1) The
owner or operator of an affected source that is located at a major
source site shall submit a summary report to the Administrator to
document the ongoing compliance status of the affected source. The
report shall contain the information identified in paragraph (g)(3) of
this [[Page 4975]] section, and shall be submitted semiannually except
when:
    (i) The Administrator determines on a case-by-case basis that more
frequent reporting is necessary to accurately assess the compliance
status of the source; or
    (ii) The monitoring data collected by the owner or operator of the
affected source in accordance with Sec. 63.343(c) show that the
emission limit has been exceeded, in which case quarterly reports shall
be submitted. Once an owner or operator of an affected source reports
an exceedance, ongoing compliance status reports shall be submitted
quarterly until a request to reduce reporting frequency under paragraph
(g)(2) of this section is approved.
    (2) Request to reduce frequency of ongoing compliance status
reports. (i) An owner or operator who is required to submit ongoing
compliance status reports on a quarterly (or more frequent basis) may
reduce the frequency of reporting to semiannual if all of the following
conditions are met:
    (A) For 1 full year (e.g., 4 quarterly or 12 monthly reporting
periods), the ongoing compliance status reports demonstrate that the
affected source is in compliance with the relevant emission limit;
    (B) The owner or operator continues to comply with all applicable
recordkeeping and monitoring requirements of subpart A of this part and
this subpart; and
    (C) The Administrator does not object to a reduced reporting
frequency for the affected source, as provided in paragraphs (g)(2)
(ii) and (iii) of this section.
    (ii) The frequency of submitting ongoing compliance status reports
may be reduced only after the owner or operator notifies the
Administrator in writing of his or her intention to make such a change,
and the Administrator does not object to the intended change. In
deciding whether to approve a reduced reporting frequency, the
Administrator may review information concerning the source's entire
previous performance history during the 5-year recordkeeping period
prior to the intended change, or the recordkeeping period since the
source's compliance date, whichever is shorter. Records subject to
review may include performance test results, monitoring data, and
evaluations of an owner or operator's conformance with emission
limitations and work practice standards. Such information may be used
by the Administrator to make a judgment about the source's potential
for noncompliance in the future. If the Administrator disapproves the
owner or operator's request to reduce reporting frequency, the
Administrator will notify the owner or operator in writing within 45
days after receiving notice of the owner or operator's intention. The
notification from the Administrator to the owner or operator will
specify the grounds on which the disapproval is based. In the absence
of a notice of disapproval within 45 days, approval is automatically
granted.
    (iii) As soon as the monitoring data required by Sec. 63.343(c)
show that the source is not in compliance with the relevant emission
limit, the frequency of reporting shall revert to quarterly, and the
owner shall state this exceedance in the ongoing compliance status
report for the next reporting period. After demonstrating ongoing
compliance with the relevant emission limit for another full year, the
owner or operator may again request approval from the Administrator to
reduce the reporting frequency as allowed by paragraph (g)(2) of this
section.
    (3) Contents of ongoing compliance status reports. The owner or
operator of an affected source for which compliance monitoring is
required in accordance with Sec. 63.343(c) shall prepare a summary
report to document the ongoing compliance status of the source. The
report must contain the following information:
    (i) The company name and address of the affected source;
    (ii) An identification of the operating parameter that is monitored
for compliance determination, as required by Sec. 63.343(c);
    (iii) The relevant emission limitation for the affected source, and
the operating parameter value, or range of values, that correspond to
compliance with this emission limitation as specified in the
notification of compliance status required by paragraph (e) of this
section;
    (iv) The beginning and ending dates of the reporting period;
    (v) A description of the type of process performed in the affected
source;
    (vi) The total operating time of the affected source during the
reporting period;
    (vii) If the affected source is a hard chromium electroplating tank
and the owner or operator is limiting the maximum cumulative rectifier
capacity in accordance with Sec. 63.342(c)(2), the actual cumulative
rectifier capacity expended during the reporting period, on a month-by-
month basis;
    (viii) A summary of operating parameter values, including the total
duration of excess emissions during the reporting period as indicated
by those values, the total duration of excess emissions expressed as a
percent of the total source operating time during that reporting
period, and a breakdown of the total duration of excess emissions
during the reporting period into those that are due to process upsets,
control equipment malfunctions, other known causes, and unknown causes;
    (ix) A certification by a responsible official, as defined in
Sec. 63.2, that the work practice standards in Sec. 63.342(f) were
followed in accordance with the operation and maintenance plan for the
source;
    (x) If the operation and maintenance plan required by
Sec. 63.342(f)(3) was not followed, an explanation of the reasons for
not following the provisions, an assessment of whether any excess
emission and/or parameter monitoring exceedances are believed to have
occurred, and a copy of the report(s) required by Sec. 63.342(f)(3)(iv)
documenting that the operation and maintenance plan was not followed;
    (xi) A description of any changes in monitoring, processes, or
controls since the last reporting period;
    (xii) The name, title, and signature of the responsible official
who is certifying the accuracy of the report; and
    (xiii) The date of the report.
    (4) When more than one monitoring device is used to comply with the
continuous compliance monitoring required by Sec. 63.343(c), the owner
or operator shall report the results as required for each monitoring
device. However, when one monitoring device is used as a backup for the
primary monitoring device, the owner or operator shall only report the
results from the monitoring device used to meet the monitoring
requirements of this subpart. If both devices are used to meet these
requirements, then the owner or operator shall report the results from
each monitoring device for the relevant compliance period.
    (h) Ongoing compliance status reports for area sources. The
requirements of this paragraph do not alleviate affected area sources
from complying with the requirements of State or Federal operating
permit programs under 40 CFR part 71.
    (1) The owner or operator of an affected source that is located at
an area source site shall prepare a summary report to document the
ongoing compliance status of the affected source. The report shall
contain the information identified in paragraph (g)(3) of this section,
shall be completed annually and retained on site, and made available to
the Administrator upon request. The report shall be completed annually
[[Page 4976]] except as provided in paragraph (h)(2) of this section.
    (2) Reports of exceedances. (i) If both of the following conditions
are met, semiannual reports shall be prepared and submitted to the
Administrator:
    (A) The total duration of excess emissions (as indicated by the
monitoring data collected by the owner or operator of the affected
source in accordance with Sec. 63.343(c)) is 1 percent or greater of
the total operating time for the reporting period; and
    (B) The total duration of malfunctions of the add-on air pollution
control device and monitoring equipment is 5 percent or greater of the
total operating time.
    (ii) Once an owner or operator of an affected source reports an
exceedance as defined in paragraph (h)(2)(i) of this section, ongoing
compliance status reports shall be submitted semiannually until a
request to reduce reporting frequency under paragraph (h)(3) of this
section is approved.
    (iii) The Administrator may determine on a case-by-case basis that
the summary report shall be completed more frequently and submitted, or
that the annual report shall be submitted instead of being retained on
site, if these measures are necessary to accurately assess the
compliance status of the source.
    (3) Request to reduce frequency of ongoing compliance status
reports. (i) An owner or operator who is required to submit ongoing
compliance status reports on a semiannual (or more frequent) basis, or
is required to submit its annual report instead of retaining it on
site, may reduce the frequency of reporting to annual and/or be allowed
to maintain the annual report onsite if all of the following conditions
are met:
    (A) For 1 full year (e.g., 2 semiannual or 4 quarterly reporting
periods), the ongoing compliance status reports demonstrate that the
affected source is in compliance with the relevant emission limit;
    (B) The owner or operator continues to comply with all applicable
recordkeeping and monitoring requirements of subpart A of this part and
this subpart; and
    (C) The Administrator does not object to a reduced reporting
frequency for the affected source, as provided in paragraphs (h)(3)
(ii) and (iii) of this section.
    (ii) The frequency of submitting ongoing compliance status reports
may be reduced only after the owner or operator notifies the
Administrator in writing of his or her intention to make such a change,
and the Administrator does not object to the intended change. In
deciding whether to approve a reduced reporting frequency, the
Administrator may review information concerning the source's previous
performance history during the 5-year recordkeeping period prior to the
intended change, or the recordkeeping period since the source's
compliance date, whichever is shorter. Records subject to review may
include performance test results, monitoring data, and evaluations of
an owner or operator's conformance with emission limitations and work
practice standards. Such information may be used by the Administrator
to make a judgement about the source's potential for noncompliance in
the future. If the Administrator disapproves the owner or operator's
request to reduce reporting frequency, the Administrator will notify
the owner or operator in writing within 45 days after receiving notice
of the owner or operator's intention. The notification from the
Administrator to the owner or operator will specify the grounds on
which the disapproval is based. In the absence of a notice of
disapproval within 45 days, approval is automatically granted.
    (iii) As soon as the monitoring data required by Sec. 63.343(c)
show that the source is not in compliance with the relevant emission
limit, the frequency of reporting shall revert to semiannual, and the
owner shall state this exceedance in the ongoing compliance status
report for the next reporting period. After demonstrating ongoing
compliance with the relevant emission limit for another full year, the
owner or operator may again request approval from the Administrator to
reduce the reporting frequency as allowed by paragraph (h)(3) of this
section.
    (i) Reports associated with trivalent chromium baths. The
requirements of this paragraph do not alleviate affected sources from
complying with the requirements of State or Federal operating permit
programs under title V. Owners or operators complying with the
provisions of Sec. 63.342(e) are not subject to paragraphs (a) through
(h) of this section, but must instead submit the following reports:
    (1) Within 180 days after January 25, 1995, submit an initial
notification that includes:
    (i) The same information as is required by paragraphs (c)(1) (i)
through (v) of this section; and
    (ii) A statement that a trivalent chromium process that
incorporates a wetting agent will be used to comply with
Sec. 63.342(e); and
    (iii) The list of bath components that comprise the trivalent
chromium bath, with the wetting agent clearly identified; and
    (2) Within 30 days of the compliance date specified in
Sec. 63.343(a), a notification of compliance status that contains an
update of the information submitted in accordance with paragraph (i)(1)
of this section or a statement that the information is still accurate;
and
    (3) Within 30 days of a change to the trivalent chromium
electroplating process, a report that includes:
    (i) A description of the manner in which the process has been
changed and the emission limitation, if any, now applicable to the
affected source;
    (ii) If a different emission limitation applies, the applicable
information required by paragraph (c)(1) of this section; and
    (iii) The notification and reporting requirements of paragraphs
(d), (e), (f), (g), and (h) of this section, which shall be submitted
in accordance with the schedules identified in those paragraphs.

                 Table 1 to Subpart N of Part 63.--General Provisions Applicability to Subpart N
----------------------------------------------------------------------------------------------------------------
                                      Applies to
   General provisions reference        subpart N                               Comment
----------------------------------------------------------------------------------------------------------------
63.1(a)(1).......................  Yes.............  Additional terms defined in Sec. 63.341; when overlap
                                                      between subparts A and N occurs, subpart N takes
                                                      precedence.
63.1(a)(2).......................  Yes
63.1(a)(3).......................  Yes
63.1(a)(4).......................  Yes.............  Subpart N clarifies the applicability of each paragraph in
                                                      subpart A to sources subject to subpart N.
63.1(a)(6).......................  Yes
63.1(a)(7).......................  Yes
63.1(a)(8).......................  Yes


[[Page 4977]]63.1(a)(10).........  Yes
63.1(a)(11)......................  Yes.............  Sec. 63.347(a) of subpart N also allows report submissions
                                                      via fax and on electronic media.
63.1(a)(12)-(14).................  Yes
63.1(b)(1).......................  No..............  Sec. 63.340 of subpart N specifies applicability.
63.1(b)(2).......................  Yes
63.1(b)(3).......................  No..............  This provision in subpart A is being deleted. Also, all
                                                      affected area and major sources are subject to subpart N;
                                                      there are no exemptions.
63.1(c)(1).......................  Yes.............  Subpart N clarifies the applicability of each paragraph in
                                                      subpart A to sources subject to subpart N.
63.1(c)(2).......................  Yes.............  Subpart N specifies permit requirements for area sources.
63.1(c)(4).......................  Yes
63.1(c)(5).......................  No..............  Subpart N clarifies that an area source that becomes a
                                                      major source is subject to the requirements for major
                                                      sources.
63.1(e)..........................  Yes
63.2.............................  Yes.............  Additional terms defined in Sec. 63.341; when overlap
                                                      between subparts A and N occurs, subpart N takes
                                                      precedence.
63.3.............................  Yes.............  Other units used in subpart N are defined in that subpart.
63.4.............................  Yes
63.5(a)..........................  Yes.............  Except replace the term ``source'' and ``stationary
                                                      source'' in Sec. 63.5(a)(1) and (2) of subpart A with
                                                      ``affected resources.''
63.5(b)(1).......................  Yes
63.5(b)(3).......................  Yes.............  Applies only to major affected sources.
63.5(b)(4).......................  No..............  Subpart N (Sec. 63.345) specifies requirements for the
                                                      notification of construction or reconstruction for
                                                      affected sources that are not major.
63.5(b)(5).......................  Yes
63.5(b)(6).......................  Yes
63.5(d)(1)(i)....................  No..............  Sec. 63.345(c)(5) of subpart N specifies when the
                                                      application or notification shall be submitted.
63.5(d)(1)(ii)...................  Yes.............  Applies to major affected sources that are new or
                                                      reconstructed.
63.5(d)(1)(iii)..................  Yes.............  Except information should be submitted with the
                                                      Notification of Compliance Status required by Sec.
                                                      63.347(e) of subpart N.
63.5(d)(2).......................  Yes.............  Applies to major affected sources that are new or
                                                      reconstructed except: (1) replace ``source'' in Sec.
                                                      63.5(d)(2) of subpart A with ``affected source''; and (2)
                                                      actual control efficiencies are submitted with the
                                                      Notification of Compliance Status required by Sec.
                                                      63.347(e).
63.5(d)(3)-(4)...................  Yes.............  Applies to major affected sources that are new or
                                                      reconstructed.
63.5(e)..........................  Yes.............  Applies to major affected sources that are new or
                                                      reconstructed.
63.5(f)(1).......................  Yes.............  Except replace ``source'' in Sec. 63.5(f)(1) of subpart A
                                                      with ``affected source.''
63.5(f)(2).......................  No..............  New or reconstructed affected sources shall submit the
                                                      request for approval of construction or reconstruction
                                                      under Sec. 63.5(f) of subpart A by the deadline specified
                                                      in Sec. 63.345(c)(5) of subpart N.
63.6(a)..........................  Yes
63.6(b)(1)-(2)...................  Yes.............  Except replace ``source'' in Sec. 63.6(b)(1)-(2) of part A
                                                      with ``affected source.''
63.6(b)(3)-(4)...................  Yes
63.6(b)(5).......................  Yes.............  Except replace ``source'' in Sec. 63.6(b)(5) of subpart A
                                                      with ``affected source.''
63.6(b)(7).......................  No..............  Provisions for new area sources that become major sources
                                                      are contained in Sec. 63.343(a)(4) of subpart N.
63.6(c)(1)-(2)...................  Yes.............  Except replace ``source'' in Sec. 63.6(c)(1)-(2) of subpart
                                                      A with ``affected source.''
63.6(c)(5).......................  No..............  Compliance provisions for existing area sources that become
                                                      major sources are contained in Sec. 63.343(a)(3) of
                                                      subpart N.
63.6(e)..........................  No..............  Sec. 63.342(f) of subpart N contains work practice
                                                      standards (operation and maintenance requirements) that
                                                      override these provisions.
63.6(f)(1).......................  No..............  Sec. 63.342(b) of subpart N specifies when the standards
                                                      apply.
63.6(f)(2)(i)-(ii)...............  Yes
63.6(f)(2)(iii)..................  No..............  Sec. 63.344(b) of subpart N specifies instances in which
                                                      previous performance test results for existing sources are
                                                      acceptable.
63.6(f)(2)(iv)...................  Yes
63.6(f)(2)(v)....................  Yes
63.6(f)(3).......................  Yes
63.6(g)..........................  Yes
63.6(h)..........................  No..............  Subpart N does not contain any opacity or visible emission
                                                      standards.
63.6(i)(1).......................  Yes
63.6(i)(2).......................  Yes.............  Except replace ``source'' in Sec. 63.6(i)(2)(i) and (ii) of
                                                      subpart A with ``affected source.''
63.6(i)(3).......................  Yes
63.6(i)(4)(i)....................  No..............  Sec. 63.343(a)(6) of subpart N specifies the procedures for
                                                      obtaining an extension of compliance and the date by which
                                                      such requests must be submitted.
63.6(i)(4)(ii)...................  Yes
63.6(i)(5).......................  Yes
63.6(i)(6)(i)....................  Yes.............  This paragraph only references ``paragraph (i)(4) of this
                                                      section'' for compliance extension provisions. But, Sec.
                                                      63.343(a)(6) of subpart N also contains provisions for
                                                      requesting a compliance extension.
63.6(i)(6)(ii)...................  Yes
63.6(i)(7).......................  Yes


[[Page 4978]]63.6(i)(8)..........  Yes.............  This paragraph only references ``paragraphs (i)(4) through
                                                      (i)(6) of this section'' for compliance extension
                                                      provisions. But, Sec. 63.343(a)(6) of subpart N also
                                                      contains provisions for requesting a compliance extension.
63.6(i)(9).......................  Yes.............  This paragraph only references ``paragraphs (i)(4) through
                                                      (i)(6) of this section'' and ``paragraphs (i)(4) and
                                                      (i)(5) of this section'' for compliance extension
                                                      provisions. But, Sec. 63.343(a)(6) of subpart N also
                                                      contains provisions for requesting a compliance extension.
63.6(i)(10)(i)-(iv)..............  Yes
63.6(i)(10)(v)(A)................  Yes.............  This paragraph only references `'paragraph (i)(4)'' for
                                                      compliance extension provisions. But, Sec. 63.343(a)(6) of
                                                      subpart N also contains provisions for requesting a
                                                      compliance extension.
63.6(i)(10)(v)(B)................  Yes
63.6(i)(11)......................  Yes
63.6(i)(12)(i)...................  Yes.............  This paragraph only references ``paragraph (i)(4)(i) or
                                                      (i)(5) of this section'' for compliance extension
                                                      provisions. But, Sec. 63.343(a)(6) of subpart N also
                                                      contains provisions for requesting a compliance extension.
63.6(i)(12)(ii)-(iii)............  Yes
63.6(i)(13)......................  Yes
63.6(i)(14)......................  Yes
63.6(i)(16)......................  Yes
63.6(j)..........................  Yes
63.7(a)(1).......................  Yes
63.7(a)(2)(i)-(vi)...............  Yes
63.7(a)(2)(ix)...................  Yes
63.7(a)(3).......................  Yes
63.7(b)(1).......................  No..............  Sec. 63.347(d) of subpart N requires notification prior to
                                                      the performance test. Sec. 63.344(a) of subpart N requires
                                                      submission of a site-specific test plan upon request.
63.7(b)(2).......................  Yes
63.7(c)..........................  No..............  Sec. 63.344(a) of subpart N specifies what the test plan
                                                      should contain, but does not require test plan approval or
                                                      performance audit samples.
63.7(d)..........................  Yes.............  Except replace ``source'' in the first sentence of Sec.
                                                      63.7(d) of subpart A with ``affected source.''
63.7(e)..........................  Yes.............  Subpart N also contains test methods specific to affected
                                                      sources covered by that subpart.
63.7(f)..........................  Yes.............  Sec. 63.344(c)(2) of subpart N identifies CARB Method 425
                                                      as acceptable under certain conditions.
63.7(g)(1).......................  No..............  Subpart N identifies the items to be reported in the
                                                      compliance test [Sec. 63.344(a)] and the timeframe for
                                                      submitting the results [Sec. 63.347(f)].
63.7(g)(3).......................  Yes
63.7(h)(1)-(2)...................  Yes
63.7(h)(3)(i)....................  Yes.............  This paragraph only references ``Sec. 63.6(i)'' for
                                                      compliance extension provisions. But, Sec. 63.343(a)(6) of
                                                      subpart N also contains provisions for requesting a
                                                      compliance extension.
63.7(h)(3)(ii)-(iii).............  Yes
63.7(h)(4)-(5)...................  Yes
63.8(a)(1).......................  Yes
63.8(a)(2).......................  No..............  Work practice standards are contained in Sec. 63.342(f) of
                                                      subpart N.
63.8(a)(4).......................  No
63.8(b)(1).......................  Yes
63.8(b)(2).......................  No..............  Sec. 63.344(d) of subpart N specifies the monitoring
                                                      location when there are multiple sources.
63.8(b)(3).......................  No..............  Sec. 63.347(g)(4) of subpart N identifies reporting
                                                      requirements when multiple monitors are used.
63.8(c)(1)(i)....................  No..............  Subpart N requires proper maintenance of monitoring devices
                                                      expected to be used by sources subject to subpart N.
63.8(c)(1)(ii)...................  No..............  Sec. 63.342(f)(3)(iv) of subpart N specifies reporting when
                                                      the O&M plan is not followed.
63.8(c)(1)(iii)..................  No..............  Sec. 63.343(f)(2) identifies the criteria for whether O&M
                                                      procedures are acceptable.
63.8(c)(2)-(3)...................  No..............  Sec. 63.344(d)(2) requires appropriate use of monitoring
                                                      devices.
63.8(c)(4)-(7)...................  No
63.8(d)..........................  No..............  Maintenance of monitoring devices is required by Secs.
                                                      63.342(f) and 63.344(d)(2) of subpart N.
63.8(e)..........................  No..............  There are no performance evaluation procedures for the
                                                      monitoring devices expected to be used to comply with
                                                      subpart N.
63.8(f)(1).......................  Yes
63.8(f)(2).......................  No..............  Instances in which the Administrator may approve
                                                      alternatives to the monitoring methods and procedures of
                                                      subpart N are contained in Sec. 63.343(c)(8) of subpart N.
63.8(f)(3).......................  Yes
63.8(f)(4).......................  Yes
63.8(f)(5).......................  Yes
63.8(f)(6).......................  No..............  Subpart N does not require the use of CEM's.
63.8(g)..........................  No..............  Monitoring data does not need to be reduced for reporting
                                                      purposes because subpart N requires measurement once/day.
63.9(a)..........................  Yes
63.9(b)(1)(i)-(ii)...............  No..............  Sec. 63.343(a)(3) of subpart N requires area sources to
                                                      comply with major source provisions if an increase in HAP
                                                      emissions causes them to become major sources.
63.9(b)(1)(iii)..................  No..............  Sec. 63.347(c)(2) of subpart N specifies initial
                                                      notification requirements for new or reconstructed
                                                      affected sources.
63.9(b)(2).......................  No..............  Sec. 63.347(c)(1) of subpart N specifies the information to
                                                      be contained in the initial notification.
63.9(b)(3).......................  No..............  Sec. 63.347(c)(2) of subpart N specifies notification
                                                      requirements for new or reconstructed sources that are not
                                                      major affected sources.
[[Page 4979]]

63.9(b)(4).......................  No
63.9(b)(5).......................  No
63.9(c)..........................  Yes.............  This paragraph only references ``Sec. 63.6(i)(4) through
                                                      Sec. 63.6(i)(6)'' for compliance extension provisions.
                                                      But, Sec. 63.343(a)(6) of subpart N also contains
                                                      provisions for requesting a compliance extension. Subpart
                                                      N provides a different timeframe for submitting the
                                                      request than Sec. 63.6(i)(4).
63.9(d)..........................  Yes.............  This paragraph only references ``the notification dates
                                                      established in paragraph (g) of this section.'' But, Sec.
                                                      63.347 of subpart N also contains notification dates.
63.9(e)..........................  No..............  Notification of performance test is required by Sec.
                                                      63.347(d) of subpart N.
63.9(f)..........................  No
63.9(g)..........................  No..............  Subpart N does not require a performance evaluation or
                                                      relative accuracy test for monitoring devices.
63.9(h)(1)-(3)...................  No..............  Sec. 63.347(e) of subpart N specifies information to be
                                                      contained in the notification of compliance status and the
                                                      timeframe for submitting this information.
63.9(h)(5).......................  No..............  Similar language has been incorporated into Sec.
                                                      63.347(e)(2)(iii) of subpart N.
63.9(h)(6).......................  Yes
63.9(i)..........................  Yes
63.9(j)..........................  Yes
63.10(a).........................  Yes
63.10(b)(1)......................  Yes
63.10(b)(2)......................  No..............  Sec. 63.346(b) of subpart N specifies the records that must
                                                      be maintained.
63.10(b)(3)......................  No..............  Subpart N applies to major and area sources.
63.10(c).........................  No..............  Applicable requirements of Sec. 63.10(c) have been
                                                      incorporated into Sec. 63.346(b) of subpart N.
63.10(d)(1)......................  Yes
63.10(d)(2)......................  No..............  Sec. 63.347(f) of subpart N specifies the timeframe for
                                                      reporting performance test results.
63.10(d)(3)......................  No..............  Subpart N does not contain opacity or visible emissions
                                                      standards.
63.10(d)(4)......................  Yes
63.10(d)(5)......................  No..............  Sec. 63.342(f)(3)(iv) and Sec. 63.347(g)(3) of subpart N
                                                      specify reporting associated with malfunctions.
63.10(e).........................  No..............  Sec. 63.347(g) and (h) of subpart N specify the frequency
                                                      of periodic reports of monitoring data used to establish
                                                      compliance. Applicable requirements of Sec. 63.10(e) have
                                                      been incorporated into Sec. 63.347(g) and (h).
63.10(f).........................  Yes
63.11............................  No..............  Flares will not be used to comply with the emmission
                                                      limits.
63.12-63.15......................  Yes
----------------------------------------------------------------------------------------------------------------

    3. Appendix A to part 63 is amended by adding Methods 306 and 306a
in numerical order to read as follows:

Appendix A to part 63--Test Methods

* * * * *

Method 306--Determination of Chromium Emissions From Decorative and
Hard Chromium Electroplating and Anodizing Operations

1. Applicability and Principle

    1.1 Applicability. This method applies to the determination of
chromium (Cr) in emissions from decorative and hard chrome
electroplating facilities and anodizing operations.
    1.2 Principle. (a) A sample is extracted isokinetically from the
source using an unheated Method 5 sampling train (40 CFR part 60,
appendix A), with a glass nozzle and probe liner, but with the
filter omitted. The Cr emissions are collected in an alkaline
solution: 0.1 N sodium hydroxide (NaOH) or 0.1 N sodium bicarbonate
(NaHCO<INF>3). The collected samples remain in the alkaline solution
until analysis. Samples with high Cr concentrations may be analyzed
using inductively coupled plasma emission spectrometry (ICP) at
267.72 nm. Alternatively, if improved detection limits are required,
a portion of the alkaline impinger solution is digested with nitric
acid and analyzed by graphite furnace atomic absorption spectroscopy
(GFAAS) at 357.9 nm.
    (b) If it is desirable to determine hexavalent chromium
(Cr<SUP>+6) emissions, the samples may be analyzed using an ion
chromatograph equipped with a post-column reactor (IC/PCR) and a
visible wavelength detector. To increase sensitivity for trace
levels of Cr<SUP>+6, a preconcentration system can be used in
conjunction with the IC/PCR.

2. Range, Sensitivity, Precision, and Interferences

    2.1  Range. The recommended analytical range for each of the
three analytical techniques is given below. The upper limit of all
three techniques can be extended indefinitely by appropriate
dilution.
    2.1.1  GFAAS Range. As reported in Method 7191 of SW-846
(Citation 5 in Bibliography), the optimum concentration range for
GFAAS is 5 to 100 <greek-m>g Cr/l of concentrated analyte.
    2.1.2  ICP Range. A linear response curve for ICP can be
obtained in the range of 10 to at least 500 <greek-m>g Cr/l of
absorbing solution.
    2.1.3  IC/PCR Range. In 40 CFR part 266, appendix IX, the lower
limit of the detection range for IC/PCR when employing a
preconcentration procedure is reported to be about 0.1 <greek-m>g
Cr<SUP>+6/l of absorbing solution.
    2.2  Sensitivity.
    2.2.1  Analytical Sensitivity.
    2.2.1.1  ICP Analytical Sensitivity. The minimum detection limit
for ICP, as reported in Method 6010A of SW-846, is 7 <greek-m>g Cr/
l.
    2.2.1.2  GFAAS Analytical Sensitivity. The minimum detection
limit for GFAAS, as reported in Method 7191 of SW-846, is 1
<greek-m>g Cr/l.
    2.2.1.3  IC/PCR Analytical Sensitivity. The minimum detection
limit for IC/PCR with a preconcentrator, as reported in 40 CFR part
266, appendix IX is 0.05 <greek-m>g Cr<SUP>+6/l.
    2.2.2  In-stack Sensitivity. The in-stack sensitivity depends
upon the analytical detection limit, the volume of stack gas
sampled, and the total volume of the impinger absorbing solution
plus the rinses. Using the analytical detection limits given in
sections 2.2.1.1, 2.2.1.2, and 2.2.1.3; a stack gas sample volume of
1.7 dscm; and a total liquid sample volume of 500 ml; the
corresponding in-stack detection limits are 0.0021 mg Cr/dscm for
ICP, 0.00015 mg Cr/dscm for GFAAS, and 0.000015 mg Cr<SUP>+6/dscm
for IC/PCR with preconcentration. However, it is recommended that
the concentration of Cr in the analytical solutions be at least five
times the analytical detection limit to optimize sensitivity in the
analyses. Using this guideline and the same assumptions for impinger
sample volume and stack gas sample volume (500 ml and 1.7 dscm,
respectively), the recommended minimum stack concentrations for
optimum sensitivity are 0.0103 mg Cr/dscm for ICP, 0.00074 mg Cr/
dscm for GFAAS, and 0.000074 mg Cr<SUP>+6/dscm for IC/PCR with
preconcentration. If required, the in-stack detection limits can be
improved by either increasing the stack gas sample volume,
[[Page 4980]] reducing the volume of the digested sample for GFAAS,
improving the analytical detection limits, or any combination of the
three.
    2.3  Precision. The following precision data have been reported
for the three analytical methods. In the case of the GFAAS there is
also bias data. In all cases, when sampling precision is combined
with analytical precision, the resulting overall precision may be
lower.
    2.3.1  GFAAS Precision. As reported in Method 7191 of SW-846, in
a single laboratory (EMSL), using Cincinnati, Ohio tap water spiked
at concentrations of 19, 48, and 77 <greek-m>g Cr/l, the standard
deviations were <plus-minus>0.1, <plus-minus>0.2, and
<plus-minus>0.8, respectively. Recoveries at these levels were 97
percent, 101 percent, and 102 percent, respectively.
    2.3.2  ICP Precision. As reported in Method 6010A of SW-846, in
an EPA round-robin Phase 1 study, seven laboratories applied the ICP
technique to acid/distilled water matrices that had been spiked with
various metal concentrates. For true values of 10, 50, and 150
<greek-m>g Cr/l; the mean reported values were 10, 50, and 149
<greek-m>g Cr/l; and the mean percent relative standard deviations
were 18, 3.3, and 3.8 percent, respectively.
    2.3.3  IC/PCR Precision. As reported in 40 CFR part 266,
appendix IX, the precision of the IC/PCR with sample
preconcentration is 5 to 10 percent; the overall precision for
sewage sludge incinerators emitting 120 ng/dscm of Cr<SUP>+6 and 3.5
<greek-m>g/dscm of total Cr is 25 percent and 9 percent for
Cr<SUP>+6 and total Cr, respectively; and for hazardous waste
incinerators emitting 300 ng/dscm of Cr<SUP>+6 the precision is 20
percent.
    2.4  Interferences.
    2.4.1  GFAAS Interferences. Low concentrations of calcium and/or
phosphate may cause interferences; at concentrations above 200
<greek-m>g/l, calcium's effect is constant and eliminates the effect
of phosphate. Calcium nitrate is therefore added to the concentrated
analyte to ensure a known constant effect. Other matrix modifiers
recommended by the instrument manufacturer may also be suitable.
Nitrogen should not be used as the purge gas due to cyanide band
interference. Background correction may be required because of
possible significant levels of nonspecific absorption and scattering
at the 357.9 nm analytical wavelength. Zeeman or Smith-Hieftje
background correction is recommended to correct for interferences
due to high levels of dissolved solids in the alkaline impinger
solutions.
    2.4.2  ICP Interferences.
    2.4.2.1  ICP Spectral Interferences. (a) Spectral interferences
are caused by:
    (1) Overlap of a spectral line from another element;
    (2) Unresolved overlap of molecular band spectra;
    (3) Background contribution from continuous or recombination
phenomena; and
    (4) Stray light from the line emission of high-concentration
elements.
    (b) Spectral overlap may be compensated for by computer
correcting the raw data after monitoring and measuring the
interfering element. At the 267.72-nm Cr analytical wavelength,
iron, manganese, and uranium are potential interfering elements.
Background and stray light interferences can usually be compensated
for by a background correction adjacent to the analytical line.
Unresolved overlap requires the selection of an alternative Cr
wavelength. Consult the instrument manufacturer's operation manual
for interference correction procedures.
    2.4.2.2  ICP Physical Interferences. High levels of dissolved
solids in the samples may cause significant inaccuracies due to salt
buildup at the nebulizer and torch tips. This problem can be
controlled by diluting the sample or providing for extended rinse
times between sample analyses. Standards are prepared in the same
matrix as the samples (i.e., 0.1 N NaOH or 0.1 N NaHCO<INF>3).
    2.4.2.3  ICP Chemical Interferences. These include molecular
compound formation, ionization effects and solute vaporization
effects, and are usually not significant in ICP, especially if the
standards and samples are matrix matched.
    2.4.3  IC/PCR Interferences. Components in the sample matrix may
cause Cr<SUP>+6 to convert to trivalent chromium (Cr<SUP>+3) or
cause Cr<SUP>+3 to convert to Cr<SUP>+6. The chromatographic
separation of Cr<SUP>+6 using ion chromatography reduces the
potential for other metals to interfere with the post-column
reaction. For the IC/PCR analysis, only compounds that coelute with
Cr<SUP>+6 and affect the diphenylcarbazide reaction will cause
interference. Periodic analyses of reagent water blanks are used to
demonstrate that the analytical system is essentially free of
contamination. Sample cross-contamination that can occur when high-
level and low-level samples or standards are analyzed alternately is
eliminated by thorough purging of the sample loop. Purging can
easily be achieved by increasing the injection volume of the samples
to ten times the size of the sample loop.

3. Apparatus

    3.1  Sampling Train. A schematic of the sampling train used in
this method is shown in Figure 306-1. The train is the same as
Method 5, section 2.1 (40 CFR part 60, appendix A), except that the
filter is omitted, and quartz or borosilicate glass must be used for
the probe nozzle and liner in place of stainless steel. It is not
necessary to heat the probe liner. Probe fittings of plastic such as
Teflon, polypropylene, etc. are recommended over metal fittings to
prevent contamination. If desired, a single combined probe nozzle
and liner may be used, but such a single glass piece is not a
requirement of this methodology. Use 0.1 N NaOH or 0.1 N NaHCO<INF>3
in the impingers in place of water.
    3.2  Sample Recovery. Same as Method 5, section 2.2 (40 CFR part
60, appendix A), with the following exceptions:
    3.2.1  Probe-Liner and Probe-Nozzle Brushes. Brushes are not
necessary for sample recovery. If a probe brush is used, it must be
nonmetallic.
    3.2.2  Sample Recovery Solution. Use 0.1 N NaOH or 0.1 N
NaHCO<INF>3, whichever was used as the impinger absorbing solution,
in place of acetone to recover the sample.
    3.2.3  Sample Storage Containers. Polyethylene, with leak-free
screw cap, 500 ml or 1,000 ml.
    3.2.4  Filtration Apparatus for IC/PCR. Teflon, or equivalent,
filter holder and 0.45 <greek-m>m acetate, or equivalent, filter.
    3.3  Analysis. For analysis, the following equipment is needed.
    3.3.1  General.
    3.3.1.1  Phillips Beakers. (Phillips beakers are preferred, but
regular beakers can also be used.)
    3.3.1.2  Hot Plate.
    3.3.1.3   Volumetric Flasks. Class A, various sizes as
appropriate.
    3.3.1.4  Assorted Pipettes.
    3.3.2  Analysis by GFAAS.
    3.3.2.1  Chromium Hollow Cathode Lamp or Electrodeless Discharge
Lamp.
    3.3.2.2  Graphite Furnace Atomic Absorption Spectrophotometer.

    3.3.3  Analysis by ICP.

    3.3.3.1  ICP Spectrometer. Computer-controlled emission
spectrometer with background correction and radio frequency
generator.
    3.3.3.2  Argon Gas Supply. Welding grade or better.
    3.3.4  Analysis by IC/PCR.

     3.3.4.1  IC/PCR System. High performance liquid chromatograph
pump, sample injection valve, post-column reagent delivery and
mixing system, and a visible detector, capable of operating at 520
nm, all with a nonmetallic (or inert) flow path. An electronic peak
area mode is recommended, but other recording devices and
integration techniques are acceptable provided the repeatability
criteria and the linearity criteria for the calibration curve
described in section 6.4.1 can be satisfied. A sample loading system
will be required if preconcentration is employed.
    3.3.4.2  Analytical Column. A high performance ion chromatograph
(HPIC) nonmetallic column with anion separation characteristics and
a high loading capacity designed for separation of metal chelating
compounds to prevent metal interference. Resolution described in
section 5.5 must be obtained. A nonmetallic guard column with the
same ion-exchange material is recommended.
    3.3.4.3  Preconcentration Column. An HPIC nonmetallic column
with acceptable anion retention characteristics and sample loading
rates as described in section 5.5.

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    3.3.4.4  0.45-<greek-m>m Filter Cartridge. For the removal of
insoluble material. To be used just prior to sample injection/
analysis.

4. Reagents

    Unless otherwise indicated, all reagents shall conform to the
specifications established by the Committee on Analytical Reagents
of the American Chemical Society (ACS reagent grade). Where such
specifications are not available, use the best available grade.
    4.1  Sampling.
    4.1.1  Water. Reagent water that conforms to ASTM Specification
D1193-77, Type II (incorporated by reference--see Sec. 63.14). It is
recommended that water blanks be checked prior to preparing sampling
reagents to ensure that the Cr content is less than the analytical
detection limit.
    4.1.2  Sodium Hydroxide (NaOH) Absorbing Solution, 0.1 N or
Sodium Bicarbonate (NaHCO<INF>3) Absorbing Solution, 0.1 N. Dissolve
4.0 g of sodium hydroxide in 1 l of water, or dissolve 8.5 g of
sodium bicarbonate in 1 l of water.
    4.2  Sample Recovery.
    4.2.1  0.1 N NaOH or 0.1 N NaHCO<INF>3. See section 4.1.2. Use
the same solution for recovery as was used in the impingers.
    4.2.2  pH Indicator Strip, for IC/PCR. pH indicator capable of
determining the pH of solutions between the pH range of 7 and 12, at
0.5 pH intervals.
    4.3  Sample Preparation and Analysis.
    4.3.1  Nitric Acid (HNO<INF>3), Concentrated, for GFAAS. Trace
metals grade or better HNO<INF>3 must be used for reagent
preparation. The ACS reagent grade HNO<INF>3 is acceptable for
cleaning glassware.
    4.3.2  HNO<INF>3, 1.0 percent (v/v), for GFAAS. Add, with
stirring, 10 ml of concentrated HNO<INF>3 to 800 ml of water. Dilute
to 1,000 ml with water. This reagent shall contain less than 0.001
mg Cr/l.
    4.3.3  Calcium Nitrate Ca(NO<INF>3)2 Solution (10 <greek-m>g Ca/
ml) for GFAAS. Prepare the solution by weighing 36 mg of
Ca(NO<INF>3)<INF>2 into a 1 l volumetric flask. Dilute with water to
1 l.
    4.3.4  Matrix Modifier, for GFAAS. See instrument manufacturer's
manual for suggested matrix modifier.
    4.3.5  Chromatographic Eluent, for IC/PCR. The eluent used in
the analytical system is ammonium sulfate based. Prepare by adding
6.5 ml of 29 percent ammonium hydroxide (NH<INF>4OH) and 33 g of
ammonium sulfate ((NH<INF>4)<INF>2SO<INF>4) to 500 ml of reagent
water. Dilute to 1 l with reagent water and mix well. Other
combinations of eluents and/or columns may be employed provided peak
resolution, as described in section 5.5, repeatability and
linearity, as described in section 6.4.1, and analytical sensitivity
are acceptable.
    4.3.6  Post-Column Reagent, for IC/PCR. An effective post-column
reagent for use with the chromatographic eluent described in section
4.3.5 is a diphenylcarbazide (DPC) based system. Dissolve 0.5 g of
1,5-diphenylcarbazide in 100 ml of ACS grade methanol. Add 500 ml of
reagent water containing 50 ml of 96 percent spectrophotometric
grade sulfuric acid. Dilute to 1 l with reagent water.
    4.3.7  Chromium Standard Stock Solution (1,000 mg/l). Procure a
certified aqueous standard or dissolve 2.829 g of potassium
dichromate (K<INF>2Cr<INF>2O<INF>7,) in water and dilute to 1 l.
      4.3.8  Calibration Standards for GFAAS. Chromium solutions for
GFAAS calibration shall be prepared to contain 1.0 percent (v/v)
HNO<INF>3. The zero standard shall be 1.0 percent (v/v) HNO<INF>3.
Calibration standards should be prepared daily by diluting the Cr
standard stock solution (section 4.3.7) with 1.0 percent HNO<INF>3.
Use at least four standards to make the calibration curve. Suggested
levels are 0, 5, 50, and 100 <greek-m>g Cr/l.
    4.3.9  Calibration Standards for ICP or IC/PCR. Prepare
calibration standards for ICP or IC/PCR by diluting the Cr standard
stock solution (section 4.3.7) with 0.1 N NaOH or 0.1 N NaHCO<INF>3,
whichever was used as the impinger absorbing solution, to achieve a
matrix similar to the actual field samples. Suggested levels are 0,
25, 50, and 100 <greek-m>g Cr/l for ICP, and 0, 0.5, 5, and 10
<greek-m>g Cr<SUP>+6/l for IC/PCR.
    4.4  Glassware Cleaning Reagents.
    4.4.1  HNO<INF>3, Concentrated. The ACS reagent grade or
equivalent.
    4.4.2  Water. Reagent water that conforms to ASTM Specification
D1193-77, Type II, (incorporated by reference--see Sec. 63.14).
     4.4.3 HNO<INF>3, 10 percent (v/v). Add with stirring 500 ml of
concentrated HNO<INF>3 to a flask containing approximately 4,000 ml
of water. Dilute to 5,000 ml with water. Mix well. The reagent shall
contain less than 2 <greek-m>g Cr/l.

5. Procedure

    5.1  Sampling. (a) Same as Method 5, section 4.1 (40 CFR part
60, appendix A), except omit the filter and filter holder from the
sampling train, use a glass nozzle and probe liner, do not heat the
probe, place 100 ml of 0.1 N NaOH or 0.1 N NaHCO<INF>3 in each of
the first two impingers, and record the data for each run on a data
sheet such as the one shown in Figure 306-2.
    (b) Clean all glassware prior to sampling in hot soapy water
designed for laboratory cleaning of glassware. Next, rinse the
glassware three times with tap water, followed by three additional
rinses with reagent water. Then soak all glassware in 10 percent (v/
v) HNO<INF>3 solution for a minimum of 4 hours, rinse three times
with reagent water, and allowed to air dry. Cover all glassware
openings where contamination can occur with Parafilm, or equivalent,
until the sampling train is assembled for sampling.
    (c) If the sample is going to be analyzed for Cr<SUP>+6 using
IC/PCR, determine the pH of the solution in the first impinger at
the end of the sampling run using a pH indicator strip. The pH of
the solution should be greater than 8.5. If not, the concentration
of the NaOH or NaHCO<INF>3 impinger absorbing solution should be
increased to 0.5 N and the sample should be rerun.
    5.2  Sample Recovery. Follow the basic procedures of Method 5,
section 4.2, with the exceptions noted below; a filter is not
recovered from this train.
    5.2.1  Container No. 1. Measure the volume of the liquid in the
first, second, and third impingers and quantitatively transfer into
a labelled sample container. Use approximately 200 to 300 ml of 0.1
N NaOH or 0.1 N NaHCO<INF>3 to rinse the probe nozzle, probe liner,
three impingers, and connecting glassware; add this rinse to the
same container.
    5.2.2  Container No. 2 (Reagent Blank). Place approximately 500
ml of 0.1 N NaOH or 0.1 N NaHCO<INF>3 absorbing solution in a
labeled sample container.
    5.2.3  Sample Filtration for IC/PCR. If the sample is to be
analyzed for Cr<SUP>+6 by IC/PCR, it must be filtered immediately
following recovery to remove any insoluble matter. Nitrogen gas may
be used as a pressure assist to the filtration process. Filter the
entire contents of Container No. 1 through a 0.45-<greek-m>m acetate
filter (or equivalent), and collect the filtrate in a 1,000 ml
graduated cylinder. Rinse the sample container with reagent water
three separate times, pass these rinses through the filter, and add
the rinses to the sample filtrate. Determine the final volume of the
filtrate and rinses and return them to the rinsed polyethylene
sample container.
    5.2.4  Sample Preservation. Refrigerate samples upon receipt.
(Containers Nos. 1 and 2).
    5.3  Sample Preparation and Analysis for GFAAS. For analysis by
GFAAS, an acid digestion of the alkaline impinger solution is
required. Two types of blanks are required for the analysis. The
calibration blank is used in establishing the analytical curve, and
the reagent blank is used to assess possible contamination resulting
from the sample processing. The 1.0 percent HNO<INF>3 is the
calibration blank. The 0.1 N NaOH solution or the 0.1 N NaHCO<INF>3
from section 5.2.2 is the reagent blank. The reagent blank must be
carried through the complete analytical procedure, including the
acid digestion, and must contain the same acid concentration in the
final solution as the sample solutions.
    5.3.1  Acid Digestion for GFAAS. (a) In a beaker, add 10 ml of
concentrated HNO<INF>3 to a sample aliquot of 100 ml taken for
analysis. Cover the beaker with a watch glass. Place the beaker on a
hot plate and reflux the sample down to near dryness. Add another 5
ml of concentrated HNO<INF>3 to complete the digestion. Carefully
reflux the sample volume down to near dryness. Wash down the beaker
walls and watch glass with reagent water. The final concentration of
HNO<INF>3 in the solution should be 1 percent (v/v). Transfer the
digested sample to a 50 ml volumetric flask. Add 0.5 ml of
concentrated HNO<INF>3, and 1 ml of the 10 <greek-m>g/ml of Ca
(NO<INF>3)<INF>2.
    (b) Dilute to 50 ml with reagent water. A different final volume
may be used, based on the expected Cr concentration, but the
HNO<INF>3 concentration must be maintained at 1 percent (v/v).

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    5.3.2 Sample Analysis by GFAAS. (a) The 357.9-nm wavelength line
shall be used. Follow the manufacturer's operating instructions for
all other spectrophotometer parameters.
    (b) Furnace parameters suggested by the manufacturer should be
employed as guidelines. Since temperature-sensing mechanisms and
temperature controllers can vary between instruments and/or with
time, the validity of the furnace parameters must be periodically
confirmed by systematically altering the furnace parameters while
analyzing a standard. In this manner, losses of analyte due to
higher-than-necessary temperature settings or losses in sensitivity
due to less than optimum settings can be minimized. Similar
verification of furnace parameters may be required for complex
sample matrices. Calibrate the GFAAS system following the procedures
specified in section 6.
    (c) Inject a measured aliquot of digested sample into the
furnace and atomize. If the concentration found exceeds the
calibration range, the sample should be diluted with the calibration
blank solution (1.0 percent HNO<INF>3) and reanalyzed. Consult the
operator's manual for suggested injection volumes. The use of
multiple injections can improve accuracy and help detect furnace
pipetting errors.
    (d) Analyze a minimum of one matrix-matched reagent blank per
sample batch to determine if contamination or any memory effects are
occurring. Analyze a calibration blank and a midpoint calibration
check standard after approximately every 10 sample injections.
    (e) Calculate the Cr concentrations:
    (1) By the method of standard additions (see operator's manual),
    (2) From the calibration curve, or
    (3) Directly from the instrument's concentration readout. All
dilution or concentration factors must be taken into account. All
results should be reported in <greek-m>g Cr/ml with up to three
significant figures.
    5.4  Sample Analysis by ICP. (a) The ICP measurement is
performed directly on the alkaline impinger solution; acid digestion
is not necessary provided the samples and standards are matrix
matched. However, ICP should only be used when the solution analyzed
has a Cr concentration greater than 35 <greek-m>g/l.
    (b) Two types of blanks are required for the analysis. The
calibration blank is used in establishing the analytical curve, and
the reagent blank is used to assess possible contamination resulting
from sample processing. Use either 0.1 N NaOH or 0.1 N NaHCO<INF>3,
whichever was used for the impinger absorbing solution, for the
calibration blank. The calibration blank can be prepared fresh in
the laboratory; it does not have to be from the same batch of
solution that was used in the field. Prepare a sufficient quantity
to flush the system between standards and samples. The reagent blank
(section 5.2.2) is a sample of the impinger solution used for sample
collection that is collected in the field during the testing
program.
    (c) Set up the instrument with proper operating parameters
including wavelength, background correction settings (if necessary),
and interfering element correction settings (if necessary). The
instrument must be allowed to become thermally stable before
beginning performance of measurements (usually requiring at least 30
min of operation prior to calibration). During this warmup period,
the optical calibration and torch position optimization may be
performed (consult the operator's manual).
    (d) Calibrate the instrument according to the instrument
manufacturer's recommended procedures, and the procedures specified
in section 6.3. Before analyzing the samples, reanalyze the highest
calibration standard as if it were a sample. Concentration values
obtained should not deviate from the actual values by more than 5
percent, or the established control limits, whichever is lower (see
sections 6 and 7). If they do, follow the recommendations of the
instrument manufacturer to correct for this condition.
    (e) Flush the system with the calibration blank solution for at
least 1 min before the analysis of each sample or standard. Analyze
the midpoint calibration standard and the calibration blank after
each 10 samples. Use the average intensity of multiple exposures for
both standardization and sample analysis to reduce random error.
    (f) Dilute and reanalyze samples that are more concentrated than
the linear calibration limit or use an alternate, less sensitive Cr
wavelength for which quality control data are already established.
    (g) If dilutions are performed, the appropriate factors must be
applied to sample values. All results should be reported in
<greek-m>g Cr/ml with up to three significant figures.
    5.5  Sample Analyses by IC/PCR. (a) The Cr<SUP>+6 content of the
sample filtrate is determined by IC/PCR. To increase sensitivity for
trace levels of chromium, a preconcentration system is also used in
conjunction with the IC/PCR.
    (b) Prior to preconcentration and/or analysis, filter all field
samples through a 0.45-<greek-m>m filter. This filtration should be
conducted just prior to sample injection/analysis.
    (c) The preconcentration is accomplished by selectively
retaining the analyte on a solid absorbent (as described in section
3.4.3.3), followed by removal of the analyte from the absorbent.
Inject the sample into a sample loop of the desired size (use
repeated loadings or a larger size loop for greater sensitivity).
The Cr<SUP>+6 is collected on the resin bed of the column. Switch
the injection valve so that the eluent displaces the concentrated
Cr<SUP>+6 sample, moving it off the preconcentration column and onto
the IC anion separation column. After separation from other sample
components, the Cr<SUP>+6 forms a specific complex in the post-
column reactor with the DPC reaction solution, and the complex is
detected by visible absorbance at a wavelength of 520 nm. The amount
of absorbance measured is proportional to the concentration of the
Cr<SUP>+6 complex formed. Compare the IC retention time and the
absorbance of the Cr<SUP>+6 complex with known Cr<SUP>+6 standards
analyzed under identical conditions to provide both qualitative and
quantitative analyses.
    (d) Two types of blanks are required for the analysis. The
calibration blank is used in establishing the analytical curve, and
the reagent blank is used to assess possible contamination resulting
from sample processing. Use either 0.1 N NaOH or 0.1 N NaHCO<INF>3,
whichever was used for the impinger solution, for the calibration
blank. The calibration blank can be prepared fresh in the
laboratory; it does not have to be from the same batch of solution
that was used in the field. The reagent blank (section 5.2.2) is a
sample of the impinger solution used for sample collection that is
collected in the field during the testing program.
    (e) Prior to sample analysis, establish a stable baseline with
the detector set at the required attenuation by setting the eluent
flow rate at approximately 1 ml/min and the post-column reagent flow
rate at approximately 0.5 ml/min. Note: As long as the ratio of
eluent flow rate to PCR flow rate remains constant, the standard
curve should remain linear. Inject a sample of reagent water to
ensure that no Cr<SUP>+6 appears in the water blank.
    (f) First, inject the calibration standards prepared, as
described in section 4.3.9 to cover the appropriate concentration
range, starting with the lowest standard first. Next, inject, in
duplicate, the calibration reference standard (as described in
section 7.3.1), followed by the reagent blank (section 5.2.2), and
the field samples. Finally, repeat the injection of the calibration
standards to assess instrument drift. Measure areas or heights of
the Cr<SUP>+6/DPC complex chromatogram peaks. The response for
replicate, consecutive injections of samples must be within 5
percent of the average response, or the injection should be repeated
until the 5 percent criterion can be met. Use the average response
(peak areas or heights) from the duplicate injections of calibration
standards to generate a linear calibration curve. From the
calibration curve, determine the concentrations of the field samples
employing the average response from the duplicate injections.

6. Calibration

    6.1  Sampling Train Calibration. Perform all of the calibrations
described in Method 5, section 5 (40 CFR part 60, appendix A). The
alternate calibration procedures described in section 7 of Method 5
(40 CFR part 60, appendix A) may also be used.
    6.2  GFAAS Calibration. Either run a series of chromium
standards and a calibration blank and construct a calibration curve
by plotting the concentrations of the standards against the
absorbencies, or using the method of standard additions, plot added
concentration versus absorbance. For instruments that read directly
in concentration, set the curve corrector to read out the proper
concentration, if applicable. This is customarily performed
automatically with most instrument computer-based data systems.
    6.2.1  GFAAS Calibration Curve. If a calibration curve is used,
it should be prepared daily with a minimum of a calibration blank
and three standards. Calibration standards for total chromium should
start with 1 percent v/v HNO<INF>3 with [[Page 4985]] no chromium
for the calibration blank, with appropriate increases in total
chromium concentration for the other calibration standards (see
section 4.3.9.). Calibration standards should be prepared fresh
daily.
    6.3  ICP Calibration. Calibrate the instrument according to the
instrument manufacturer's recommended procedures, using a
calibration blank and three standards for the initial calibration.
Calibration standards should be prepared fresh daily, as described
in section 4.3.9. Be sure that samples and calibration standards are
matrix matched. Flush the system with the calibration blank between
each standard. Use the average intensity of multiple exposures for
both standardization and sample analysis to reduce random error.
    6.4  IC/PCR Calibration. Prepare a calibration curve using the
calibration blank and three calibration standards prepared fresh
daily as described in section 4.3.9. Run the standards with the
field samples as described in section 5.5.

7. Quality Control

    7.1  GFAAS Quality Control
    7.1.1  GFAAS Calibration Reference Standards. If a calibration
curve is used, it must be verified by use of at least one
calibration reference standard (made from a reference material or
other independent standard material) at or near the mid-range of the
calibration curve. The calibration reference standard must be
measured within 10 percent of it's true value for the curve to be
considered valid. The curve must be validated before sample analyses
are performed.
    7.1.2  GFAAS Check Standards. (a) Run a check standard and a
calibration blank after approximately every 10 sample injections,
and at the end of the analytical run. These standards are run, in
part, to monitor the life and performance of the graphite tube. Lack
of reproducibility or a significant change in the signal for the
check standard indicates that the graphite tube should be replaced.
Check standards can be the mid-range calibration standard or the
reference standard. The results of the check standard shall agree
within 10 percent of the expected value. If not, terminate the
analyses, correct the problem, recalibrate the instrument, and
reanalyze all samples analyzed subsequent to the last acceptable
check standard analysis.
    (b) The results of the calibration blank are to agree within
three standard deviations of the mean blank value. If not, repeat
the analysis two more times and average the results. If the average
is not within three standard deviations of the background mean,
terminate the analyses, correct the problem, recalibrate, and
reanalyze all samples analyzed subsequent to the last acceptable
calibration blank analysis.
    7.1.3  GFAAS Duplicate Samples. Run one duplicate sample for
every 20 samples, (or one per source test, whichever is more
frequent). Duplicate samples are brought through the whole sample
preparation and analytical process separately. Duplicate samples
shall agree within 10 percent.
    7.1.4  GFAAS Matrix Spiking. Spiked samples shall be prepared
and analyzed daily to ensure that correct procedures are being
followed and that all equipment is operating properly. Spiked sample
recovery analyses should indicate a recovery for the Cr spike of
between 75 and 125 percent. Spikes are added prior to any sample
preparation. Cr levels in the spiked sample should provide final
solution concentrations that fall within the linear portion of the
calibration curve.
    7.1.5  GFAAS Method of Standard Additions. Whenever sample
matrix problems are suspected and standard/sample matrix matching is
not possible or whenever a new sample matrix is being analyzed, the
method of standard additions shall be used for the analysis of all
extracts. Section 5.4.2 of Method 12 (40 CFR part 60, appendix A)
specifies a performance test to determine if the method of standard
additions is necessary.
    7.1.6  GFAAS Reagent Blank Samples. Analyze a minimum of one
matrix-matched reagent blank (section 5.2.2) per sample batch to
determine if contamination or memory effects are occurring. The
results should agree within three standard deviations of the mean
blank value.
    7.2  ICP Quality Control.
    7.2.1  ICP Interference Check. Prepare an interference check
solution to contain known concentrations of interfering elements
that will provide an adequate test of the correction factors in the
event of potential spectral interferences. Two potential
interferences, iron and manganese, may be prepared as 1,000
<greek-m>g/ml and 200 <greek-m>g/ml solutions, respectively. The
solutions should be prepared in dilute HNO<INF>3 (1-5 percent).
Particular care must be taken to ensure that the solutions and/or
salts used to prepare the solutions are of ICP grade purity (i.e.,
that no measurable Cr contamination exists in the salts/solutions).
Commercially prepared interfering element check standards are
available. Verify the interelement correction factors every three
months by analyzing the interference check solution. The correction
factors are calculated according to the instrument manufacturer's
directions. If interelement correction factors are used properly, no
false Cr should be detected.
    7.2.2  ICP Calibration Reference Standards. Prepare a
calibration reference standard in the same alkaline matrix as the
calibration standards; it should be at least 10 times the
instrumental detection limit. This reference standard should be
prepared from a different Cr stock solution source than that used
for preparation of the calibration curve standards and is used to
verify the accuracy of the calibration curve. Prior to sample
analysis, analyze at least one reference standard. The calibration
reference standard must be measured within 10 percent of it's true
value for the curve to be considered valid. The curve must be
validated before sample analyses are performed.
    7.2.3  ICP Check Standards. Run a check standard and a
calibration blank after every 10 samples, and at the end of the
analytical run. Check standards can be the mid-range calibration
standard or the reference standard. The results of the check
standard shall agree within 10 percent of the expected value; if
not, terminate the analyses, correct the problem, recalibrate the
instrument, and rerun all samples analyzed subsequent to the last
acceptable check standard analysis. The results of the calibration
blank are to agree within three standard deviations of the mean
blank value. If not, repeat the analysis two more times and average
the results. If the average is not within three standard deviations
of the background mean, terminate the analyses, correct the problem,
recalibrate, and reanalyze all samples analyzed subsequent to the
last acceptable calibration blank analysis.
    7.2.4  ICP Duplicate Samples. Analyze one duplicate sample for
every 20 samples, (or one per source test, whichever is more
frequent). Duplicate samples are brought through the whole sample
preparation and analytical process. Duplicate samples shall agree
within 10 percent.
    7.2.5  ICP Reagent Blank Samples. Analyze a minimum of one
matrix-matched reagent blank (section 5.2.2) per sample batch to
determine if contamination or memory effects are occurring. The
results should agree within three standard deviations of the mean
blank value.
    7.3  IC/PCR Quality Control.
    7.3.1  IC/PCR Calibration Reference Standards. Prepare a
calibration reference standard in the same alkaline matrix as the
calibration standards at a concentration that is at or near the mid-
point of the calibration curve. This reference standard should be
prepared from a different Cr stock solution source than that used
for preparing the calibration curve standards. The reference
standard is used to verify the accuracy of the calibration curve.
Prior to sample analysis, analyze at least one reference standard.
The results of this analysis of the reference standard must be
within 10 percent of the true value of the reference standard for
the calibration curve to be considered valid. The curve must be
validated before sample analyses are performed.
    7.3.2  IC/PCR Check Standards. (a) Run the calibration blank and
calibration standards with the field samples as described in section
5.5. For each standard, determine the peak areas (recommended) or
the peak heights, calculate the average response from the duplicate
injections, and plot the average response against the Cr+6
concentration in <greek-m>g/l. The individual responses for each
calibration standard determined before and after field sample
analysis must be within 5 percent of the average response for the
analysis to be valid. If the 5 percent criteria is exceeded,
excessive drift and/or instrument degradation may have occurred, and
must be corrected before further analyses are performed.
    (b) Employing linear regression, calculate a predicted value for
each calibration standard using the average response for the
duplicate injections. Each predicted value must be within 7 percent
of the actual value for the calibration curve to be considered
acceptable. If not acceptable, remake and/or rerun the calibration
standards. If the calibration curve is still unacceptable, reduce
the range of the curve.
    7.3.3  IC/PCR Duplicate Samples. Analyze one duplicate sample
for every 20 samples, (or one per source test, whichever is more
frequent). Duplicate samples are brought through the whole sample
preparation and [[Page 4986]] analytical process. Duplicate samples
shall agree within 10 percent.
    7.3.4  ICP Reagent Blank Samples. Analyze a minimum of one
matrix-matched reagent blank (section 5.2.2) per sample batch to
determine if contamination or memory effects are occurring. The
results should agree within three standard deviations of the mean
blank value.

8. Emission Calculations

    Carry out the calculations, retaining one extra decimal figure
beyond that of the acquired data. Round off figures after final
calculations.
    8.1 Total Cr in Sample. Calculate M<INF>Cr, the total <greek-m>g
Cr in each sample, as follows:

M<INF>Cr = (V<INF>ml) (C<INF>S) (F) (D)    Eq.306-1
where:

V<INF>ml = Volume of impinger contents plus rinses, ml.
C<INF>S = Concentration of Cr in sample solution, <greek-m>g Cr/ml.
F = Dilution factor.
= Volume of aliquot after dilution, ml; Volume of aliquot before
dilution, ml
D = Digestion factor.
= Volume of sample aliquot after digestion, ml; Volume of sample
aliquot submitted to digestion, ml

    8.2  Average Dry Gas Meter Temperature and Average Orifice
Pressure Drop. Same as Method 5, section 6.2.
    8.3  Dry Gas Volume, Volume of Water Vapor, Moisture Content.
Same as Method 5, sections 6.3, 6.4, and 6.5, respectively.
    8.4 Cr  Emission Concentration. Calculate C<INF>Cr, the Cr
concentration in the stack gas, in mg/dscm on a dry basis, corrected
to standard conditions, as follows:

C<INF>Cr=(10<SUP>-3 mg/<greek-m>g) (M<INF>Cr/V<INF>m(std))    Eq.
306-2
where:

 V<INF>m(std)=Gas sample volume measured by the dry gas meter,
corrected to dry standard conditions, dscm.

    8.5  Isokinetic Variation, Acceptable Results. Same as Method 5,
sections 6.11 and 6.12, respectively.

9. Bibliography

    1. ``Test Methods for Evaluating Solid Waste, Physical/Chemical
Methods,'' U. S. Environmental Protection Agency Publication SW-846,
2nd Edition, July 1982.
    2. Cox, X.B., R.W. Linton, and F.E. Butler. Determination of
Chromium Speciation in Environmental Particles--A Multitechnique
Study of Ferrochrome Smelter Dust. Accepted for publication in
Environmental Science and Technology.
    3. Same as Bibliography of Method 5, Citations 2 to 5 and 7.
    4. California Air Resources Board, ``Determination of Total
Chromium and Hexavalent Chromium Emissions from Stationary
Sources.'' Method 425, September 12, 1990.
    5. ``Test Methods for Evaluating Solid Waste, Physical/ Chemical
Methods'', U. S. Environmental Protection Agency Publication SW-846,
3rd Edition, November 1986 as amended by Update I , November 1990.

Method 306A--Determination of Chromium Emissions From Decorative and
Hard Chromium Electroplating and Anodizing Operations

1. Applicability and Principle

    1.1  Applicability. This method applies to the determination of
chromium (Cr) in emissions from decorative and hard chromium
electroplating facilities and anodizing operations. The method is
less expensive and less complex to conduct than Method 306 of this
appendix. Correctly applied, the precision and bias of the sample
results will be comparable to those obtained with the isokinetic
Method 306 of this appendix. This method is applicable under ambient
moisture, air, and temperature conditions.
    1.2  Principle. A sample is extracted from the source at a
constant sampling rate determined by a critical orifice and
collected in a probe and impingers. The sampling time at the
sampling traverse points is varied according to the stack gas
velocity at each point to obtain a proportional sample. The
concentration is determined by the same analytical procedures used
in Method 306 of this appendix: inductively-coupled plasma emission
spectrometry (ICP), graphite furnace atomic absorption spectrometry
(GFAAS), or ion chromatography with a post-column reactor (IC/PCR).

2. Range, Sensitivity, Precision, and Interferences

    Same as Method 306, section 2 of this appendix.

3. Apparatus

    Note: Mention of trade names or specific products does not
constitute endorsement by the Environmental Protection Agency.
    3.1  Sampling Train. A schematic of the sampling train is shown
in Figure 306A-1. The components of the train are available
commercially, but some fabrication and assembly are required. If
Method 306 equipment is available, the sampling train may be
assembled as specified in Method 306 of this appendix and the
sampling rate of the meter box set at the delta H<INF>@ specified
for the calibrated orifice; this train is then operated as specified
in this method.
    3.1.1  Probe Nozzle/Tubing and Sheath. Use approximately 1/4 in.
inner diameter (ID) glass or rigid plastic tubing about 8 in. long
with a short 90 deg. bend at one end to form the nozzle. Grind a
slight taper on the nozzle end before making the bend. Attach the
nozzle to flexible tubing of sufficient length to collect a sample
from the stack. Use a straight piece of larger diameter rigid tubing
(such as metal conduit or plastic water pipe) to form a sheath that
begins about 1 in. from the 90 deg. bend on the nozzle and encases
the flexible tubing.

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    3.1.2  S-Type Pitot. Same as Method 2, section 3 (40 CFR part
60, appendix A).
    3.1.3  Sample Line. Use thick wall flexible plastic tubing
(e.g., polyethylene, polypropylene, or polyvinylchloride) about \1/
4\ in. to \3/8\ in. ID to connect the train components. A
combination of rigid plastic tubing and thin wall flexible tubing
may be used as long as neither tubing collapses when leak-checking
the train. Metal tubing cannot be used.
    3.1.4  Impingers. One quart capacity ``Mason'' glass canning
jars with vacuum seal lids are used. Three impingers are required:
the first is for collecting the absorbing solution, the second is
empty and is used to collect any absorbing solution carried over
from the first impinger, and the third contains the drying agent.
Install bleak-tight inlet and outlet tubes in the lids of each
impinger for assembly with the train. The tubes may be made of
approximately \1/4\ in. ID glass or rigid plastic tubing. For the
inlet tube of the first impinger, heat the glass or plastic tubing
and draw until the tubing separates. Cut the tip off until the tip
orifice is \3/32\ in. in diameter. When fabricating the first
impinger, place the tip orifice \3/16\ in. above the bottom of the
jar when assembled. For the second impinger, the inlet tube need not
be drawn and sized, but the tip should be approximately 2 in. above
the bottom of the jar. The inlet tube of the third impinger should
extend to about \1/2\ in. above the bottom of the jar. Locate the
outlet tube end of all impingers about \1/2\ in. beneath the bottom
of the lid.
    3.1.5  Manometer. Inclined/vertical type, or equivalent device,
as described in section 2.2 of Method 2 (40 CFR part 60, appendix
A).
    3.1.6  Critical Orifice. The critical orifice is a small
restriction in the sample line (approximately \1/16\ in. in
diameter) that is located upstream of the vacuum pump and sets the
sample rate at about 0.75 cfm. An orifice can be made of \3/32\ in.
brass tubing approximately \9/16\ in. long sealed inside larger
diameter, approximately \5/16\ in., brass tubing to serve as a
critical orifice giving a constant sample flow. Materials other than
brass can be used to construct the critical orifice as long as the
flow through the sampling train is approximately 0.75 cfm.
    3.1.7  Connecting Hardware. Standard pipe and fittings, \1/4\
in. or \1/8\ in., are used to install the vacuum pump and dry gas
meter in the sampling train.
    3.1.8  Pump Oiler. A glass oil reservoir with a wick mounted at
the vacuum pump inlet lubricates the pump vanes. The oiler should be
an inline type and not vented to the atmosphere.
    3.1.9  Vacuum Pump. Gast Model 0522-V103-G18DX, or equivalent,
capable of delivering at least 1.5 cfm at 15 in. Hg vacuum.
    3.1.10  Oil Trap. An empty glass oil reservoir without wick is
mounted at pump outlet to prevent oil from reaching the dry gas
meter.
    3.1.11  Dry Gas Meter. A Rockwell model 175-s test meter, or
equivalent, with a thermometer installed to monitor meter
temperature. The dry gas meter must be capable of measuring volume
to within 2 percent.
    3.2  Sample Recovery.
    3.2.1   Wash Bottles. These are glass or inert plastic, 500 or
1000 ml, with spray tube.
    3.2.2  Sample Containers. The first mason jar impinger of the
sampling train serves as the sample container. A new lid and plastic
wrap are substituted for the impinger inlet/outlet assembly.
    3.3  Analysis. Same as Method 306, section 3.3 of this appendix.

4. Reagents

    4.1  Sampling. Same as Method 306, section 4.1 of this appendix.
    4.2  Sample Recovery. Same as Method 306, section 4.2 of this
appendix.

5. Procedure

    5.1  Sampling.
    5.1.1  Pretest Preparation.
    5.1.1.1  Port Location. Locate the sampling ports as specified
in section 2.1 of Method 1 (40 CFR part 60, appendix A). Use a total
of 24 sampling points for round ducts and 25 points for rectangular
ducts. Locate the sampling points as specified in section 2.3 of
Method 1 (40 CFR part 60, Appendix A). Mark the pitot and sampling
probe with thin strips of tape to permit velocity and sample
traversing. For ducts less than 12 in. in diameter, use a total of
16 points.
    5.1.1.2  Velocity Pressure Traverse. (a) Perform a velocity
pressure traverse before the first sample run. Figure 306A-2 may be
used to record velocity pressure data. If testing occurs over
several days, perform the traverse at the beginning of each day.
Perform velocity pressure traverses as specified in section 3 of
Method 2 (40 CFR part 60, appendix A), but record only the
<greek-D>p (velocity head) values for each sampling point.
    (b) Check for cyclonic flow during the first traverse to verify
that it does not exist; if cyclonic flow does exist, make sure that
the absolute average angle of misalignment does not exceed 20 deg..
If the average angle of misalignment exceeds 20 deg. at an outlet
location, install straightening vanes to eliminate the cyclonic
flow. If it is necessary to test an inlet location where cyclonic
flow exists, it may not be possible to install straightening vanes.
In this case, a variation of the alignment method must be used. This
must be approved by the Administrator.

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    5.1.1.3  Point Sampling Times. Since the sampling rate of the
train is held constant by the critical orifice, it is necessary to
calculate specific sampling times for each point in order to obtain
a proportional sample. If all sampling can be completed in a single
day, it is necessary to calculate the point sampling times only
once. If sampling occurs over several days, recalculate the point
sample times each day using velocity traverse data obtained earlier
in the day. Determine the average of the <greek-D>p values obtained
during the velocity traverse (Figure 306A-2). Calculate the sampling
times for each point using Equation 306A-1. Convert the decimal
parts of minutes to seconds. If the stack diameter is less than 12
in., use 7.5 minutes in place of 5 minutes in the equation and 16
sampling points.
[GRAPHIC][TIFF OMITTED]TR25JA95.003

Where:

n=Sampling point number.
<greek-D>p=Velocity head measured by Type-S pitot tube, in. H<INF>2O

    5.1.1.4 Preparation of Sampling Train. Assemble the sampling
train as shown in Figure 306A-1. Secure the nozzle-liner assembly to
the sheath to prevent slipping when sampling. Before charging, rinse
the first mason jar impinger with either 0.1 N sodium hydroxide
(NaOH) or 0.1 N sodium bicarbonate (NaHCO<INF>3); discard the
solution. Put 250 ml of 0.1 N NaOH or 0.1 N NaHCO<INF>3 absorbing
solution into the first mason jar impinger. Similarly, rinse the
second mason jar impinger and leave empty. Put silica gel into the
third mason jar impinger until the impinger is half full. Place the
impingers into an ice bath and check to ensure that the lids are
tight.
    5.1.1.5  Train Leak Check Procedure. Wait until the ice has
cooled the impingers before sampling. Next, seal the nozzle with a
finger covered by a piece of clear plastic wrap and turn on the
pump. The vacuum in the line between the pump and the critical
orifice must be at least 15 in. Hg. Observe any leak rate on the dry
gas meter. The leak rate should not exceed 0.02 cfm.
    5.1.2  Sampling Train Operation.
    5.1.2.1  Record all pertinent process and sampling data on the
data sheet (see Figure 306A-3). Ensure that the process operation is
suitable for sample collection.

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    5.1.2.2  Place the probe/nozzle into the duct at the first
sampling point and turn on the pump. A minimum vacuum of 15 in. Hg
or 0.47 atmosphere between the critical orifice and pump is required
to maintain critical flow. Sample for the time interval previously
determined for that point. Move to the second point and sample for
the time interval determined for that point; sample all points on
the traverse in this manner. Keep ice around the impingers during
the run. Complete the traverse and turn off the pump. Move to the
next sampling port and repeat. Record the final dry gas meter
reading. (NOTE: If an approximate mass emission rate is desired,
record the stack temperature before and after the run.)
    5.1.2.3  Post Test Leak Check. Remove the probe assembly and
flexible tubing from the first impinger. Do not cover the nozzle.
Seal the inlet tube of the first impinger with a finger covered by
clear plastic wrap and turn on the pump. The vacuum in the line
between the pump and the critical orifice must be at least 15 in.
Hg. Observe any leak rate on the dry gas meter. If the leak rate
exceeds 0.02 cfm, reject the run. If the leak rate is acceptable,
take the probe assembly and impinger assembly to the sample recovery
area.
    5.2  Sample Recovery.
    5.2.1   Container No. 1. (a) After the train has been moved to
the sample recovery area, disconnect the tubing that joins the first
impinger with the second.
    (b) The first impinger jar is also used as the sample container
jar. Unscrew the lid from the first impinger jar. Lift the inlet/
outlet tube assembly almost out of the jar, and using the wash
bottle, rinse the outside of the impinger tip that was immersed in
the impinger jar with extra absorbing solution; rinse the inside of
the tip as well.
    (c) Recover the second impinger by removing the lid and pouring
any contents from the second impinger into the first impinger. Rinse
the second impinger including the inside and outside of the impinger
stem as well as any connecting plastic tubing with extra absorbing
solution and place the rinse into the first impinger.
    (d) Hold the nozzle and connecting plastic tubing in a vertical
position so that the tubing forms a ``U.'' Using the wash bottle,
partially fill the tubing with sampling reagent. Raise and lower the
end of the plastic tubing several times to cause the reagent to
contact the major portion of the internal parts of the assembly
thoroughly. Do not raise the solution level too high or part of the
sample will be lost. Place the nozzle end of the assembly over the
mouth of the first impinger jar (sample container) and elevate the
plastic tubing so that the solution flows rapidly out of the nozzle.
Perform this procedure three times. Next, repeat the recovery
procedure but allow the solution to flow rapidly out the open end of
the plastic tubing into the first impinger jar.
    (e) Place a piece of clear plastic wrap over the mouth of the
first impinger jar. Use a standard lid and band assembly to seal the
jar. Label the jar with the sample number and mark the liquid level
to gauge any losses during handling.
    5.2.2  Container No. 2 (Reagent Blank). Place approximately 500
ml of the 0.1 N NaOH or 0.1 N NaHCO<INF>3 absorbing solution in a
labeled sample container.
    5.2.3  Sample Filtration for IC/PCR. If the sample is to be
analyzed for Cr<SUP>+6 by IC/PCR, it must be filtered immediately
following recovery as described in section 5.2.3 of Method 306 of
this appendix.
    5.3  Analysis. Sample preparation and analysis procedures are
identical to Method 306, section 5.3 of this appendix.

6. Calibration

    6.1  Dry Gas Meter. (a) Dry gas meter calibrations may be
performed by either the manufacturer, a firm who provides
calibration services, or the tester. The dry gas meter calibration
coefficient (Y<INF>m) must be determined prior to initial use of the
meter, and must be checked following each field use.
    (b) If the dry gas meter is new, the manufacturer will have
specified the Y<INF>m for the meter. The manufacturer may also have
included a calibration orifice and a data sheet with the meter that
may be used for calibration purposes. The sheet will specify a
standard cubic foot volume and a sample time, and these values were
determined when the orifice was used to set the initial Y<INF>m for
the meter. The Y<INF>m may be checked by disconnecting the critical
orifice in the sampling train and replacing it with the calibration
orifice. The inlet side of the calibration orifice is open to the
atmosphere and is not reconnected to the sample train. Record the
initial dry gas meter volume and meter temperature. Turn on the pump
and operate it for the number of minutes specified by the
manufacturer's data sheet. Stop the pump and record the final dry
gas meter volume and temperature. Subtract the start volume from the
stop volume and average the temperatures. Check the Y<INF>m for the
dry gas meter after the test by using the following equation:
[GRAPHIC][TIFF OMITTED]TR25JA95.004

Where:

Ft.<SUP>3<INF>m=Cubic feet given by meter manufacturer
T<INF>m=Temperature of meter in degrees Fahrenheit
Ft<SUP>3<INF>pt=Cubic feet from dry gas meter, post test
P<INF>bar=Barometric pressure in inches of mercury

    Compare the Y<INF>m just calculated with the Ym given by the
manufacturer:
[GRAPHIC][TIFF OMITTED]TR25JA95.005

    If this value is between 0.95 and 1.05, the Y<INF>m of the meter
is acceptable. If the value lies outside the specified range, the
test series shall either be voided, or calculations for the test
series shall be performed using whichever meter coefficient value
(i.e., before and after) that gives the lower value of total sample
volume. Return the dry gas meter to the manufacturer for
recalibration. The calibration may also be conducted as specified in
section 5.3.1 or section 7 of Method 5 (40 CFR part 60, appendix A),
except that it is only necessary to check the calibration at an
approximate flow rate of 0.75 cfm. The calibration of the dry gas
meter must be checked after each field use in the same manner. If
the values of Y<INF>m obtained before and after a test series differ
by more than 5%, the test series shall either be voided, or
calculations for the test series shall be performed using whichever
meter coefficient value (i.e., before or after) that gives the lower
value of total sample volume.
    6.2  GFAA Spectrometer. Same as Method 306, section 6.2 of this
appendix.
    6.3  ICP Spectrometer. Same as Method 306, section 6.3 of this
appendix.

7. Quality Control

    Same as Method 306, section 7 of this appendix.

8. Calculations

    8.1  Pollutant Concentration. Calculate C<INF>cr, the Cr
concentration in the stack gas, in mg/dscm on a dry basis as
follows:
[GRAPHIC][TIFF OMITTED]TR25JA95.006

where:

M<INF>Cr=Amount of Cr in sample from Method 306 of this appendix,
Eq. 306-1, <greek-m>g.
T<INF>m=Dry gas meter temperature,  deg.F. [[Page 4993]]
Y<INF>m=Dry gas meter correction factor, dimensionless.
V<INF>m=Dry gas meter volume, ft<SUP>3.
P<INF>bar=Barometric pressure, in. Hg.

    8.2  Approximate Mass Emission Rate (Optional). Calculate an
approximate mass emission rate of Cr in kg/hr using the following
equation:
[GRAPHIC][TIFF OMITTED]TR25JA95.007

where:

r=Radius of stack, in.
(<radical><greek-D>p)<INF>avg=Average of <radical><greek-D>p values.
Ts=Stack temperature,  deg.F.
P<INF>bar=Barometric pressure, in. Hg.
C<INF>Cr=Concentration of Cr, mg/dscm.

    Note: The emission rate calculated using Equation 306A-3 is
based on an assumed moisture content of 2%.

9. Bibliography

    1. Clay, F.R. Memo, Impinger Collection Efficiency--Mason Jars
vs. Greenburg-Smith Impingers, Dec. 1989.
    2. Segall, R.R., W.G. DeWees, F.R. Clay, and J.W. Brown.
Development of Screening Methods for Use in Chromium Emissions
Measurement and Regulations Enforcement. In: Proceedings of the 1989
EPA/A&WMA International Symposium--Measurement of Toxic and Related
Air Pollutants, A&WMA Publication VIP-13, EPA Report No. 600/9-89-
060, p. 785.
    3. Clay, F.R. Chromium Sampling Method. In: Proceedings of the
1990 EPA/A&WMA International Symposium--Measurement of Toxic and
Related Air Pollutants, A&WMA Publication VIP-17, EPA Report No.
600/9-90-026, p. 576.
    4. Clay, F.R. Proposed Sampling Method 306A for the
Determination of Hexavalent Chromium Emissions from Electroplating
and Anodizing Facilities. In: Proceedings of the 1992 EPA/A&WMA
International Symposium--Measurement of Toxic and Related Air
Pollutants, A&WMA Publication VIP-25, EPA Report No. 600/R-92/131,
p. 209.

Method 306-B--Surface Tension Measurement and Recordkeeping for
Chromium Plating Tanks Used at Electroplating and Anodizing Facilities

1. Applicability and Principle

    1.1  Applicability. This method is applicable to all decorative
plating and anodizing operations where a wetting agent is used in
the tank as the primary mechanism for reducing emissions from the
surface of the solution.
    1.2  Principle. During an electroplating or anodizing operation,
gas bubbles generated during the process rise to the surface of the
tank liquid and burst. Upon bursting, tiny droplets of chromic acid
become entrained in ambient air. The addition of a wetting agent to
the tank bathreduces the surface tension of the liquid and
diminishes the formation of these droplets.

2. Apparatus

    2.1  Stalagmometer. Any commercially available stalagmometer or
equivalent surface tension measuring device may be used to measure
the surface tension of the plating or anodizing tank liquid.
    2.2  Preciser tensiometer. A Preciser tensiometer may be used to
measure the surface tension of the tank liquid provided the
procedures specified in ASTM Method D 1331-89, Standard Test Methods
for Surface and Interfacial Tension of Solutions of Surface Active
Agents (incorporated by reference--see Sec. 63.14) are followed.

3. Procedure

    3.1  The surface tension of the tank bath may be measured by
using a Preciser tensiometer, a stalagmometer or any other device
suitable for measuring surface tension in dynes per centimeter. If
the Preciser tensiometer is used, the instructions given in ASTM
Method D 1331-89, Standard Test Methods for Surface and Interfacial
Tension of Solutions of Surface Active Agents (incorporated by
reference--see Sec. 63.14) must be followed. If a stalagmometer or
other device is used to measure surface tension, the instructions
that came with the measuring device must be followed.
    3.2  (a) Measurements of the bath surface tension are done using
a progressive system which minimizes the number of surface tension
measurements required when the proper surface tension is maintained.
Initially, measurements must be made every 4 hours of tank operation
for the first 40 hours of tank operation after the compliance date.
Once there are no exceedances during 40 hours of tank operation,
measurements may be conducted once every 8 hours of tank operation.
Once there are no exceedances during 40 hours of tank operation,
measurements may be conducted once every 40 hours of tank operation
on an on-going basis, until an exceedance occurs. The maximum time
interval for measurements is once every 40 hours of tank operation.
    (b) If a measurement of the surface tension of the solution is
above the 40 dynes per centimeter limit, the time interval reverts
back to the original monitoring schedule of once every 4 hours. A
subsequent decrease in frequency would then be allowed according to
the previous paragraph.

4. Recordkeeping

    4.1  Log book of surface tension measurements and fume
suppressant additions. The surface tension of the plating or
anodizing tank bath must be measured as specified in section 3.2.
The measurements must be recorded in the log book. In addition to
the record of surface tension measurements, the frequency of fume
suppressant maintenance additions and the amount of fume suppressant
added during each maintenance addition will be recorded in the log
book. The log book will be readily available for inspection by
regulatory personnel.
    4.2  Instructions for apparatus used in measuring surface
tension. Also included with the log book must be a copy of the
instructions for the apparatus used for measuring the surface
tension of the plating or anodizing bath. If a Preciser tensiometer
is used, a copy of ASTM Method D 1331-89, Standard Methods for
Surface and Interfacial Tension of Solutions of Surface Active
Agents (incorporated by reference--see Sec. 63.14) must be included
with the log book.

[FR Doc. 95-65 Filed 1-24-95; 8:45 am]
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