[Federal Register Volume 62, Number 204 (Wednesday, October 22, 1997)]
[Rules and Regulations]
[Pages 54900-54947]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-27264]



[[Page 54899]]

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Part II





Environmental Protection Agency





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40 CFR Part 64, et al.



Compliance Assurance Monitoring; Final Rule

Federal Register / Vol. 62, No. 204 / Wednesday, October 22, 1997 / 
Rules and Regulations

[[Page 54900]]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 64, 70, and 71

[IL-64-2-5807; FRL-5908-6]
RIN 2060-AD18


Compliance Assurance Monitoring

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule; Final rule revisions.

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SUMMARY: Pursuant to requirements concerning enhanced monitoring and 
compliance certification under the Clean Air Act (the Act), EPA is 
promulgating new regulations and revised regulations to implement 
compliance assurance monitoring (CAM) for major stationary sources of 
air pollution that are required to obtain operating permits under title 
V of the Act. Subject to certain exemptions, the new regulations 
require owners or operators of such sources to conduct monitoring that 
satisfies particular criteria established in the rule to provide a 
reasonable assurance of compliance with applicable requirements under 
the Act. Monitoring will focus on emissions units that rely on 
pollution control device equipment to achieve compliance with 
applicable standards. The regulations also provide procedures for 
coordinating these new requirements with EPA's operating permits 
program regulations. Revisions to the operating permits program 
regulations clarify the relationship between the 64 requirements and 
periodic monitoring and compliance certification requirements. The 
rulemaking is estimated to improve compliance with existing regulations 
which will potentially reduce the need for further regulation to 
achieve clean air goals at a cost significantly less than that of the 
1993 proposed rule.

DATES: The effective date of this rule is November 21, 1997.

ADDRESSES: Docket. Supporting information used in developing the 
regulations is contained in Docket No. A-91-52. This docket is 
available for public inspection and copying between 8:00 a.m. and 5:30 
p.m. Monday through Friday, excluding government holidays, and is 
located at: EPA Air Docket (LE-131), Room M-1500, Waterside Mall, 401 M 
Street SW, Washington, DC 20460. A reasonable fee may be charged for 
copying.

FOR FURTHER INFORMATION CONTACT: Peter Westlin, U.S. Environmental 
Protection Agency, Office of Air Quality Planning and Standards, at 
(919) 541-1058.

SUPPLEMENTARY INFORMATION: The contents of the preamble are listed in 
the following outline:

I. Background and Summary of the Rulemaking

A. Statutory Authority
B. Rulemaking History
C. Overview of the CAM Approach
D. Benefits of a CAM Approach and Potential Control Costs
E. The Relationship of Part 64 to Credible Evidence and Enforcement 
Issues

II. Detailed Discussion of Regulatory Provisions

A. Section 64.1--Definitions
B. Section 64.2--Applicability
C. Section 64.3--Monitoring Design Criteria
D. Section 64.4--Submittal Requirements
E. Section 64.5--Deadlines for Submittals
F. Section 64.6--Approval of Monitoring
G. Section 64.7--Operation of Approved Monitoring
H. Section 64.8--Quality Improvement Plans (QIPs)
I. Section 64.9--Reporting and Recordkeeping Provisions
J. Section 64.10--Savings Provisions
K. Revisions to 40 CFR Part 70 and Part 71

III. Administrative Requirements

A. Docket
B. Executive Order 12866
C. Unfunded Mandates Act
D. Paperwork Reduction Act
E. Regulatory Flexibility Act
F. Submission to Congress and the General Accounting Office

    The first section of this preamble provides an introduction to the 
principles underlying EPA's CAM approach, the benefits of the part 64 
rulemaking, and background on the statutory provisions and key issues 
involved with developing the rule. This section also summarizes the 
public's participation in the development of the rulemaking. The second 
section of the preamble presents a more detailed summary of the 
regulations. This section includes a description of the provisions and 
the basic purpose of each provision. This section also describes the 
Agency's response to the comments received on the original proposal, as 
supplemented by additional comments during subsequent periods in which 
public input was requested and obtained. The preamble describes how the 
final rule has been changed from the proposal in response to the input 
received. The final section of the preamble addresses administrative 
requirements for Federal regulatory actions.
    The preamble includes many citations which refer the reader to more 
detailed discussions of a topic or to the origin of certain 
requirements. These citation sections generally will not be followed by 
their source, such as ``of this preamble'' or ``of the Act.'' Rather, 
the reader can recognize the origins of the sections by their nature: 
sections of the preamble begin with a Roman numeral; sections of the 
regulations in 40 CFR part 64 range from Secs. 64.1 to 64.11; sections 
of the regulations in 40 CFR part 70 range from Secs. 70.1 to 70.11; 
sections of other existing EPA regulations are preceded by 40 CFR; and 
sections of the Act are referenced by a three-digit number, such as 114 
or 504.
    This preamble often refers to ``State'' or ``permitting 
authority.'' The reader should assume that where the preamble refers to 
a ``State'', such term also includes local air pollution agencies, 
Indian tribes, and territories of the United States to the extent they 
are or will be the permitting authority for their area, or have been or 
will be delegated permitting responsibilities under the Act. In 
addition, the term ``permitting authority'' would also include EPA to 
the extent EPA is the permitting authority of record.
    Finally, this preamble often refers to 40 CFR part 70, the 
regulations promulgated July 21, 1992, implementing the operating 
permits program under title V of the Act (57 FR 32250). The EPA has 
proposed revisions to those regulations on August 29, 1994 (59 FR 
44460), and August 31, 1995 (60 FR 45530). Those regulations, including 
the proposed revisions, provide requirements applicable to federally-
approved, State-administered operating permits programs. Where a State 
fails to submit an approvable program or to adequately administer and 
enforce an approved program, EPA will have to promulgate, administer 
and enforce a Federal program for title V permits in that State. The 
reader should assume that where the preamble refers to 40 CFR part 70, 
such term may also refer to an EPA-administered (Federal) operating 
permits program, which EPA has promulgated under 40 CFR part 71 (see 
July 1, 1996, 61 FR 34202).

I. Background and Summary of the Rulemaking

A. Statutory Authority

    The part 64 regulations respond to the statutory mandate in the 
Clean Air Act Amendments of 1990. The 1990 Amendments contain several 
provisions directing the Agency to require owners or operators to 
conduct monitoring and to make compliance certifications. These 
provisions are set forth in both title V (operating permits provisions) 
and title VII (enforcement provisions) of the 1990 Amendments.
    Title V directs the Agency to implement monitoring and compliance 
certification requirements through the

[[Page 54901]]

operating permits program. Section 503(b)(2) requires at least annual 
certifications of compliance with permit requirements and prompt 
reporting of deviations from permit requirements. Section 504(a) 
mandates that owners or operators submit to the permitting authority 
the results of any required monitoring at least every six months. This 
section also requires permits to include ``such other conditions as are 
necessary to assure compliance with applicable requirements'' of the 
Act. Section 504(b) of the Act also allows the Agency to prescribe, by 
rule, methods and procedures for determining compliance, and states 
that continuous emission monitoring systems need not be required if 
other methods or procedures provide sufficiently reliable and timely 
information for determining compliance. Under section 504(c), each 
operating permit must ``set forth inspection, entry, monitoring, 
compliance certification, and reporting requirements to assure 
compliance with the permit terms and conditions.''
    Title VII of the 1990 Amendments added a new section 114(a)(3) that 
requires EPA to promulgate rules on enhanced monitoring and compliance 
certifications. This paragraph provides, in part:

    The Administrator shall in the case of any person which is the 
owner or operator of a major stationary source, and may, in the case 
of any other person, require enhanced monitoring and submission of 
compliance certifications. Compliance certifications shall include 
(A) identification of the applicable requirement that is the basis 
of the certification, (B) the method used for determining the 
compliance status of the source, (C) the compliance status, (D) 
whether compliance is continuous or intermittent, (E) such other 
facts as the Administrator may require.

    The 1990 Amendments also revised section 114(a)(1) of the Act to 
provide additional authority concerning monitoring, reporting, and 
recordkeeping requirements. As amended, that section provides the 
Administrator with the authority to require any owner or operator of a 
source:

    On a one-time, periodic or continuous basis to--
    (A) Establish and maintain such records;
    (B) Make such reports;
    (C) Install, use, and maintain such monitoring equipment;
    (D) Sample such emissions (in accordance with such procedures or 
methods, at such locations, at such intervals, during such periods 
and in such manner as the Administrator shall prescribe);
    (E) Keep records on control equipment parameters, production 
variables, or other indirect data when direct monitoring of 
emissions is impractical;
    (F) Submit compliance certifications in accordance with section 
114(a)(3); and
    (G) Provide such other information as the Administrator may 
reasonably require.

B. Rulemaking History

    The EPA has acted to implement the statutory provisions discussed 
above in two separate ways. First, the part 70 operating permits 
program includes basic monitoring and compliance certification 
requirements. Section 70.6(a)(3)(i) requires that permits include all 
existing monitoring and testing requirements set forth in applicable 
requirements. In many cases, the monitoring requirements in the 
underlying regulations will suffice for assessing compliance. However, 
if particular applicable requirements do not include periodic testing 
or monitoring, then Sec. 70.6(a)(3)(i)(B) requires the permit to 
include ``periodic monitoring'' to fill that gap. Section 
70.6(c)(5)(iii) requires the submittal of compliance certifications no 
less frequently than annually, and generally incorporates the language 
on compliance certifications included in section 114(a)(3) of the Act.
    To implement the statutory requirement for enhanced monitoring, EPA 
has developed through this rulemaking a general monitoring rule in 40 
CFR part 64 to be implemented through the part 70 operating permits 
program. The Agency first provided notice in the Federal Register of an 
opportunity for public review and comment on this concept in August 
1991 (see 56 FR 37700). A public information document was made 
available, a public meeting was held, and written comments were 
received after the meeting. A subsequent public meeting was held in 
August 1993, and a proposed rule was published on October 22, 1993 (58 
FR 54648). This proposed rule is referred to as the ``1993 EM 
proposal'' throughout the remainder of this preamble.
    The Agency received approximately 2000 comment letters during the 
public comment period. These letters contained several thousand 
individual comments on more than 500 major and minor issue topics. 
Because of some of the complex and difficult issues raised, the Agency 
held a series of stakeholder meetings in the fall of 1994, released 
draft sections of a possible final rule, and then officially reopened 
the public comment period on specific issues on December 28, 1994 (59 
FR 66844). An additional stakeholder meeting was held near the close of 
that reopened comment period, and more than 200 additional comment 
letters were received.
    In April 1995, EPA decided to shift the emphasis of part 64. The 
Agency issued a press release in early April 1995 that indicated EPA's 
intent to hold a public meeting to discuss the potential changes to the 
proposed enhanced monitoring rule, and then contacted various 
stakeholder groups so that they would have the opportunity to 
participate. A formal notice of the meeting was also published in the 
Federal Register on May 26, 1995 (60 FR 27943). Approximately 200 
people attended the meeting on May 31, 1995, and many additional people 
attended the follow-up meetings held in June 1995 in Washington, DC, 
Cincinnati, Austin, and Portland, Oregon. The Agency then drafted a 
preamble and rule for public discussion and comment, and held another 
public meeting in September 1995. (See 60 FR 48679, September 20, 1995, 
for the formal Federal Register notice of that meeting and request for 
comment.) Approximately 150 people attended that meeting, and EPA 
received more than 60 written comment letters on the draft rule 
package. The Agency subsequently issued a draft final part 64 and 
discussion document in August 1996 (see 61 FR 41991, August 13, 1996) 
and held another public meeting in September 1996. The 1995 and 1996 
draft rules are referred to as the ``1995 part 64 Draft'' and ``1996 
part 64 Draft,'' respectively, throughout the remainder of this 
preamble. Approximately 200 people attended and 120 written comment 
letters were submitted during the comment period. The Agency also has 
held numerous informal stakeholder discussions with interested parties 
to discuss the CAM approach, and received additional written comments 
during the period since April 1995. (See the items in sections II-D, 
II-E, IV-D, IV-E, IV-F, VI-D, VI-E, and VI-F of Docket A-91-52 for a 
complete record of written comments submitted by stakeholders, and 
discussions between EPA and interested parties concerning the 
rulemaking.)
    This preamble addresses the changes to part 64 that have been made 
in response to the significant public comment received during the 
course of the rulemaking. The focus is on documenting the changes made 
in response to the comments received on the formal 1993 proposed rule, 
as well as specific changes made in response to comments received on 
the draft rule materials made available in 1995 and 1996. The Agency 
has also prepared a detailed, three-part Response to Comments Document 
which includes a response to all material comments on

[[Page 54902]]

the rule. See Docket Items A-91-52-VII-C-1 through VII-C-3.

C. Overview of the CAM Approach

1. General Approach
    The CAM approach as defined in part 64 is intended to address the 
requirement in title VII of the 1990 Amendments that EPA promulgate 
enhanced monitoring and compliance certification requirements for major 
sources, and the related requirement in title V that operating permits 
include monitoring, compliance certification, reporting and 
recordkeeping provisions to assure compliance. The EPA has long 
recognized that obtaining ongoing compliance is a two-step process. 
First, the Agency must determine whether properly designed control 
measures--including, as applicable, control devices, process 
modifications, operating limitations or other control measures--are 
installed or otherwise employed, and that those control measures are 
proven to be capable of achieving applicable requirements. In the past, 
this step has been addressed through new source review permitting, 
initial stack testing, compliance inspections and similar mechanisms. 
The title V permit application and review process, including the 
applicant's initial compliance certification and compliance plan 
obligations, will add another tool for assuring that source owners or 
operators have adopted the proper control measures for achieving 
compliance. The second step is to monitor to determine that the source 
continues to meet applicable requirements. An important aspect of this 
second step is to assure that the control measures, once installed or 
otherwise employed, are properly operated and maintained so that they 
do not deteriorate to the point where the owner or operator fails to 
remain in compliance with applicable requirements. The Agency believes 
that monitoring, reporting, recordkeeping and ongoing or recurring 
compliance certification requirements under title VII should be 
designed so that owners or operators carry out this second step in 
assuring ongoing compliance.
    There are two basic approaches to assuring that control measures 
taken by the owner or operator to achieve compliance are properly 
operated and maintained so that the owner or operator continues to 
achieve compliance with applicable requirements. One method is to 
establish monitoring as a method for directly determining continuous 
compliance with applicable requirements. The Agency has adopted this 
approach in some rulemakings and, as discussed below, is committed to 
following this approach whenever appropriate in future rulemakings. 
Another approach is to establish monitoring for the purpose of: (1) 
Documenting continued operation of the control measures within ranges 
of specified indicators of performance (such as emissions, control 
device parameters and process parameters) that are designed to provide 
a reasonable assurance of compliance with applicable requirements; (2) 
indicating any excursions from these ranges; and (3) responding to the 
data so that excursions are corrected. The part 64 published today 
adopts this second approach as an appropriate approach to enhancing 
monitoring in the context of title V permitting for significant 
emission units that use control devices to achieve compliance with 
emission limits. For units not covered by part 64, a similar but less 
detailed approach is provided for in the monitoring and related 
recordkeeping and reporting provisions of part 70 (see 
Sec. 70.6(a)(3)).
    The rule defines ``control devices'' to mean equipment that removes 
pollutants or transforms pollutants to passive emissions (see 
Sec. 64.1), as opposed to other control measures, such as process 
modifications, material substitution, and other control options. For 
significant units that use control devices to achieve compliance, the 
owner or operator will have to develop and propose, through the part 70 
permit process, monitoring that meets specified criteria for selecting 
appropriate indicators of control performance, establishing ranges for 
those indicators, and for responding to any excursions from those 
ranges. The final rule also includes performance and operating criteria 
that must be achieved, as well as documentation requirements for the 
monitoring proposed by the owner or operator.
    The final element of part 64 is the concept of a quality 
improvement plan (QIP). Under the final rule, a QIP may be required 
where the owner or operator has failed to satisfy the general duty to 
properly operate and maintain an emissions unit (including the 
applicable control device) or the owner or operator has evidence of a 
failure to comply with an applicable requirement, as determined through 
part 64 monitoring data and/or other appropriate information (such as 
inspections). The rule allows for the permit to establish a ``bright 
line'' test for implementing a QIP, but does not require such a test.
    The QIP would include both an initial ``problem investigation'' 
phase and a ``corrective action'' phase. The rule provides for the QIP 
mechanism so that permitting authorities have a specific regulatory 
tool to address situations in which an owner or operator operates in a 
manner that involves excursions followed by ineffective actions to 
bring the monitored indicators back into the acceptable ranges 
established in the permit. Thus, the QIP will help assure that the 
owner or operator pays attention to the data and, if necessary, 
improves performance to the point where ongoing compliance with 
applicable requirements is reasonably assured. See Section II.H. for 
further discussion of QIP issues.
2. Implementation through Permits
    a. Burdens to the Permitting Process. Many commenters, including 
State and local agencies, industry, and environmental groups raised 
concerns in their comments that the part 64 process of selecting the 
appropriate monitoring for a particular source would overburden the 
permitting process and lead to poor implementation. The Agency is very 
sensitive to these concerns; however, the Agency continues to believe 
that, consistent with the preamble to the 1993 EM proposal, the permit 
implementation approach provides the greatest amount of flexibility to 
the regulated community and States while at the same time ensuring that 
enhanced monitoring will be implemented for all major sources in a 
reasonably expeditious time frame. In addition, the Agency has taken 
several significant steps in the final rule to reduce the potential 
burden to the permitting process, including the actions discussed 
below.
    i. Applicability. The focus of applicability on those pollutant-
specific emissions units that rely on control devices to achieve 
compliance has reduced the estimated number of units that will be 
subject to part 64 and also has reduced the variety of emissions unit 
types that will be affected by part 64. This reduction in the volume 
and breadth of units covered by part 64 will reduce the overall burdens 
on the permit process.
    ii. Extended Implementation Period. As discussed in Section II.E., 
the final rule provides for a new extended implementation schedule. 
Only those units which are major units based on their potential to emit 
will be subject to part 64 requirements prior to the renewal of an 
initial part 64 permit. In addition, in many cases, implementation will 
not be required for these large units until permit renewal. For the 
smaller units covered by part 64, implementation will not occur until

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permit renewal. This extended implementation schedule will relieve much 
of the burden on source owners or operators to develop and prepare 
proposed monitoring during the initial part 70 permitting process and 
will similarly relieve the burdens of the approval process on 
permitting authorities.
    iii. Guidance Development Process. The Agency is committed to 
developing non-prescriptive examples of the types of monitoring that 
can be used to satisfy part 64 for various types of control devices and 
emissions units. The guidance development process will provide an 
opportunity for source owners or operators and other interested parties 
to submit suggestions, review drafts and generally clarify the part 64 
requirements. The Agency emphasizes that the development of example 
monitoring approaches is intended to assist both regulated industry and 
permitting authorities to streamline permit review in those instances 
where a source owner or operator proposes monitoring based on one of 
the examples. These examples should not be considered as an implied 
limitation on the owner or operator's ability to propose a different 
approach that the owner or operator can demonstrate satisfies the part 
64 requirements or on the permitting authority's authority to require 
additional monitoring.
    iv. General Clarifications. Finally, the potential implementation 
burdens have been reduced by adopting many general clarifications in 
the final rule. For instance, the final rule clearly states that 
emissions units that are not subject to applicable requirements are not 
required to conduct part 64 monitoring. A second example is the 
streamlined performance and operating design criteria in the final 
rule, which are substantially less complex and burdensome than the 
comparable requirements in the appendices to the 1993 EM proposal.
    b. Creation of New Substantive Standards. Many commenters argued 
that the requirements in part 64 were inconsistent with EPA's stated 
position that the part 70 operating permits program was intended solely 
to collect existing requirements in one document, without creating new 
substantive obligations for source owners or operators. The Agency 
disagrees with these arguments. As mentioned in section I.A., the part 
64 regulations respond to the statutory mandate in the Clean Air Act 
Amendments of 1990 and the part 70 regulations implement title V of the 
Clean Air Act Amendments of 1990, which directs the Agency to implement 
monitoring and compliance certification requirements through the 
operating permits program. The part 64 requirements are independently 
applicable, substantive requirements that an owner or operator must 
achieve. The fundamental requirements of part 64 are to: (a) Monitor 
compliance in a manner that is sufficient to yield data that provide a 
reasonable assurance of compliance and allow an owner or operator to 
make an informed certification of compliance; (b) take necessary 
corrective actions in response to the monitoring data; (c) report on 
the results of such monitoring; and (d) maintain records of such 
monitoring. None of these fundamental obligations under part 64 will be 
added as part of a part 70 permit independently of part 64. What will 
be added as part of the permit process are the particulars as to how a 
specific source owner or operator will satisfy these general part 64 
requirements. This type of regulatory structure is entirely consistent 
with the purpose of a permit process which is to specify how general 
obligations will be achieved in particular circumstances.
    c. Consistency of Implementation. Implementation of part 64 through 
the part 70 permits program means that part 64 will be implemented on a 
case-by-case basis. Many industry and State and local agencies 
supported EPA's proposal to allow for a flexible implementation 
approach that allows for adopting monitoring that is most appropriate 
to a particular emission unit's circumstances. However, many industry, 
environmental and State and local agency commenters also raised 
concerns that the case-by-case implementation process in part 64 may 
not be implemented in a reasonably consistent manner by different 
permitting authorities.
    The EPA acknowledges the potential significance of these concerns; 
however, EPA believes that they have been overstated by the commenters. 
As discussed in Section II. below, EPA has taken steps to minimize 
potential inconsistencies by simplifying and clarifying the final rule. 
Also, EPA must weigh these concerns against the significant policy 
concerns that would exist if the Agency attempted to develop specific 
enhanced monitoring requirements for each NSPS and NESHAP standard, as 
well as the burdens on States to revisit each SIP regulation, as well 
as individual State preconstruction and operating permits. The 
administrative burdens associated with that approach would severely 
hinder the effective and timely implementation of enhanced monitoring 
for most sources for many years. In addition, such an approach fails to 
acknowledge the new benefits of the operating permits program to tailor 
general requirements in a manner that is most appropriate to the 
circumstances at a particular source. For these reasons, EPA believes 
that the benefits of the permit implementation approach far outweigh 
the concerns over consistency in implementation.
    d. Programmatic Options. Some stakeholders have suggested 
alternative means of implementing part 64 requirements. One alternative 
suggested was to allow a State the option of implementing part 64 
monitoring requirements through programmatic rule changes instead of 
implementing CAM through source-specific part 64 requirements. One 
potential method for allowing this option is to exempt from part 64 
monitoring any emissions units for which a State has developed 
requirements specifically designed to satisfy part 64 in a rule that 
has been submitted and approved as part of the SIP. Another would be to 
delay implementation of part 64 to provide an opportunity for a State 
to devise a competitive monitoring program for submittal to and 
approval by EPA.
    The final rule will allow states to implement CAM through 
rulemaking pertaining to categories of sources. The EPA encourages 
States to consider adding monitoring requirements to existing and new 
rules that are consistent with part 64 requirements. In this manner, 
the burdens associated with source-specific monitoring development 
could be reduced. To provide an incentive for this type of rule, the 
final rule includes a provision (see Sec. 64.4(b)) that allows the 
owner or operator to rely upon this type of programmatic rule as the 
primary documentation of the appropriateness of its monitoring. This 
approach would reduce the number of case-by-case reviews necessary to 
implement part 64.
    On the other hand, EPA does not agree with commenters who suggest 
that states that choose to use programmatic rulemaking should be 
allowed to apply different criteria in determining monitoring and to 
have additional time to implement such an approach. The EPA believes 
monitoring decisions should be made on the same basis whether done on a 
programmatic or case-by-case basis. Second, EPA questions both the need 
for a substantial delay for programmatic rulemaking and whether the 
purported advantages of a programmatic approach justify any substantial 
delay. The final part 64 does not include an option for permitting 
authorities to delay implementation of part 64 through use of a 
programmatic approach.

[[Page 54904]]

    Because of the implementation schedule for part 64 (see Section 
II.E.), owners or operators will not have to implement part 64 for many 
emissions units until renewal of initial part 70 permits. These include 
both large units that are at sources which have already received or are 
in the process of receiving part 70 permits, and smaller units for 
which the rule explicitly delays implementation until permit renewal. 
This schedule provides substantial time for States to adopt SIP 
regulations, as discussed above, that are consistent with part 64, 
especially for smaller units that could most benefit from generic 
monitoring requirements that could be developed through programmatic 
SIP rule changes.
3. Limited Purpose of Part 64
    Part 64 is intended to provide a reasonable means of supplementing 
existing regulatory provisions that are not consistent with the 
statutory requirements of titles V and VII of the 1990 Amendments to 
the Act. The EPA believes that the CAM approach is a reasonable 
approach commensurate with this role. The Agency does not believe that 
existing monitoring requirements that are more rigorous than part 64 
should be reduced or that monitoring imposed in future regulatory 
actions necessarily should be guided by part 64.
    If existing requirements are more rigorous than part 64, those 
requirements should continue to exist unaffected by part 64. This point 
is made explicitly in several instances in the final rule. In addition, 
EPA is committed to developing new emission standards subsequent to the 
1990 Amendments with methods specified for directly determining 
continuous compliance whenever possible, taking into account technical 
and economic feasibility, and other pertinent factors. In recognition 
of this EPA commitment, the rule exempts New Source Performance 
Standards (NSPS) and National Emission Standards for Hazardous Air 
Pollutants (NESHAP) rules that are proposed after the 1990 Amendments 
to the Act from part 64 requirements. The Agency believes that States 
should approach their regulatory actions from the same perspective and 
thus the Agency does not believe that part 64 will have a significant 
impact on requirements imposed subsequent to the 1990 Amendments.
    Comments on the 1996 part 64 Draft received from environmental, 
public health and labor organizations emphasized the public's right to 
information about air pollution from major stationary sources. These 
commenters argued that the CAM approach provides insufficient 
information about actual emissions and thus will frustrate the public's 
right to know about actual emissions from a source. Their comments also 
asserted that source owners should not be allowed to use information 
gathered under the CAM approach, including information on pollution 
control operations and practices, to certify compliance with applicable 
standards.
    The Agency responded to those comments (see letter from Mary 
Nichols to various environmental and other organizations dated December 
19, 1996, docket item A-91-52-VI-C-18) and summarizes its response 
here. The Agency agrees with incorporating direct emissions and 
compliance monitoring where the technology is available and feasible, 
and promoting public disclosure of air pollution emissions information. 
On the other hand, the Agency does not believe that such a broad, 
expensive, and technically complex objective can be accomplished 
through a single rulemaking at this time. Not only would trying to 
impose such monitoring requirements across the board in the short term 
be technically unrealistic, doing so would put in jeopardy the 
possibility of advancing monitoring of existing emissions sources 
through part 70 operating permits program already in progress.
    The Agency notes that current requirements for submission of 
emission statements prepared by owners of industrial air pollution 
sources continues independent of part 64 (such as statements required 
under section 182(a)(3) of the Act) and such statements will be based 
on the most currently available information, including new monitoring 
data produced under part 64.
    As described above, the Agency firmly believes that continued 
proper operation and maintenance of process operations and air 
pollution controls demonstrated capable of achieving applicable 
standards is vital to ongoing compliance. By providing the necessary 
data and requiring appropriate corrective action, part 64 will result 
in owners and operators being more conscientious in the attention paid 
to the operation and maintenance of air pollution control equipment and 
practices than has been the case in the past. This approach has proven 
effective in reducing air pollution emissions and improving compliance 
performance in the implementation of many existing regulations with 
similar requirements. See further discussion on the use of part 64 data 
for purposes of part 70 compliance certifications in Section I.C.5., 
below.
4. Relationship to Part 70 Monitoring
    Part 70 currently requires all title V operating permits to include 
monitoring to assure compliance with the permit. This includes all 
existing monitoring requirements as well as additional monitoring 
(generally referred to as ``periodic monitoring'') if current 
requirements fail to specify appropriate monitoring. As noted in the 
1993 EM proposal, because part 64 contains applicable monitoring 
requirements sufficient to demonstrate compliance with applicable 
emission limitations or standards, the part 70 periodic monitoring 
requirements will not apply to the emissions units and applicable 
requirements covered by part 64. This conclusion is equally applicable 
under the final part 64 rule. However, during the course of the 
rulemaking, two other issues have been raised that concern the 
relationship of the final part 64 rule to the existing part 70 periodic 
monitoring requirements: (1) The extent to which periodic monitoring 
should be relied on as ``enhanced monitoring'' and (2) timing concerns 
where periodic monitoring may be required prior to implementation of 
part 64.
    With respect to relying on part 70 periodic monitoring as 
``enhanced monitoring'' for at least some units, EPA suggested this 
option in both the 1993 EM proposal and the December 1994 notice 
reopening the comment period on that proposal (see 58 FR 54648, 54653 
and 59 FR 66844, 66849). Industry commenters generally supported this 
option; although, many suggested that EPA rely completely on periodic 
monitoring as ``enhanced monitoring.'' Some environmental groups, 
however, argued against this option. They asserted further that EPA's 
part 64 applicability provisions would not meet the statutory 
requirement that all major stationary sources conduct enhanced 
monitoring. The EPA considered including in part 64 requirements 
analogous to the existing part 70 provisions (see subpart C of part 64 
in the 1996 part 64 Draft). This approach would clearly indicate EPA's 
position that the part 70 monitoring requirements including periodic 
monitoring if necessary, constitute the appropriate ``enhanced 
monitoring'' for units not covered by part 64. However, in the final 
rule, EPA has determined to rely on the position originally discussed 
in the 1993 EM proposal that existing monitoring when supplemented as 
necessary by periodic monitoring is sufficiently enhanced for emissions 
units not subject to part 64. The Agency

[[Page 54905]]

decided not to pursue the Subpart C option included in the 1996 part 64 
Draft based on the comments received (see Section II.B., below) and 
also because of concerns about disrupting the ongoing implementation of 
part 70.
    Because of the delays in finalizing part 64 and the delayed 
implementation schedule included in the final rule (see Section II.E., 
below), many part 70 permits will address periodic monitoring issues 
prior to implementation of part 64. To address concerns about the 
potential duplication and disruption that this situation could cause, 
EPA has taken certain steps. First, the ``Subpart C'' option has been 
rejected and the existing part 70 monitoring, including periodic 
monitoring, requirements will continue to apply. Because the majority 
of emissions units do not use control devices, this decision will 
result in part 64 creating no duplication or disruption for the 
majority of emissions units. As discussed in the Regulatory Impact 
Analysis (RIA) for this rulemaking, EPA estimates that the final part 
64 rule will affect less than 27,000 emissions units, while an 
additional 54,000 units that could have been affected by subpart C will 
remain affected by part 70 monitoring requirements.
    Second, for units with control devices, EPA has adopted a phased 
implementation schedule under which part 64 will apply only to the 
largest units prior to the first renewal of a part 70 permit. To the 
extent part 64 and periodic monitoring may have some overlap for these 
largest units, any overlap should be minimal because these units are 
most likely to have existing monitoring that would make the periodic 
monitoring provisions in part 70 unnecessary. For the smaller units 
that will not be required to implement part 64 until part 70 permit 
renewal, the periodic monitoring provisions of part 70 may apply. While 
there may be some concern that this will result in installation of 
monitoring that could later be found inappropriate for part 64, EPA 
does not believe this would generally be the case. In many instances, 
such periodic monitoring would likely serve as the basis, in whole or 
in part, for compliance with part 64. For instance, a source owner or 
operator may conduct intermittent monitoring of visible emissions or 
certain parameters to satisfy part 70 periodic monitoring. To the 
extent successful, the experience with that monitoring could be used to 
justify its use under part 64. At the least, the experience gained 
under periodic monitoring could be used to develop data to support 
proposed part 64 monitoring at permit renewal. Such data could be used, 
for example, to justify appropriate indicator ranges, quality assurance 
procedures, monitoring frequency and similar part 64 requirements. Just 
as importantly, the continued presence of part 70 monitoring 
requirements during the initial permit term is essential to provide the 
minimum level of assurance that a source remains in compliance with a 
part 70 permit as required under title V of the Act. Thus, EPA rejects 
the position suggested by some commenters that it should immediately 
suspend the part 70 periodic monitoring requirements pending 
implementation of part 64.
5. Relationship to part 70 Compliance Certifications
    In developing an implementation approach in the 1993 EM proposal, 
EPA indicated that owners or operators must rely on methods for 
determining continuous compliance to submit a certification of whether 
compliance is continuous or intermittent. Many industry representatives 
and State and local agencies objected to the burdens associated with 
the 1993 proposal. A large part of those burdens would have occurred as 
a result of having to develop monitoring that could produce data of 
sufficient reliability to make determinations of continuous compliance 
with a degree of representativeness, accuracy, precision, and 
reliability equivalent to that provided by conducting the test method 
established for a particular requirement. In response to those 
concerns, the Agency opted to pursue the CAM approach which provides a 
reasonable assurance of compliance through monitoring of control 
operations. The EPA believes that the CAM approach does enhance 
existing monitoring requirements and provides sufficient information 
for an owner or operator to reach a conclusion about the compliance 
status of the owner or operator's source that is adequate to satisfy 
the compliance certification obligations in the Act. Such monitoring 
also provides data sufficient for EPA, permitting authorities, and the 
public to evaluate a source's compliance and to take appropriate action 
where potential compliance problems are discovered.
    The part 64 rulemaking also clarifies the Agency's interpretation 
of the phrase ``continuous or intermittent'' as used in section 
114(a)(3) of the Act. The 1993 EM proposal interpreted the requirement 
that source owners or operators certify ``whether compliance is 
continuous or intermittent'' to require monitoring sufficient to 
determine if compliance was continuous. (58 FR 54654, 54658) Thus the 
term ``continuous'' was read as meaning that compliance was achieved 
during all averaging periods for a standard and ``intermittent'' was 
read generally as meaning that one or more deviations occurred during 
the certification period. (58 FR 54665). This proposed interpretation 
was consistent with the Agency's position in the preamble to proposed 
part 70 as well (see 56 FR 21737, May 10, 1991 (``The compliance 
certification must document * * * whether compliance was continuous or 
intermittent (i.e., whether there were periods of noncompliance).'').
    The Agency reconsidered this interpretation in reopening the public 
comment period on the 1993 EM proposal and noted that ``intermittent'' 
could mean either that noncompliance had occurred or that the owner or 
operator has data sufficient to certify compliance only on an 
intermittent basis. (See 59 FR 66848, col. 2 (``nothing in section 
114(a)(3) dictates that all source owners or operators must certify to 
being in either continuous compliance or else be considered in 
noncompliance; source owners or operators may also certify to being in 
compliance as demonstrated on an intermittent basis.'')). The EPA 
believes that the statutory interpretation discussed in the preamble to 
the 1993 EM proposal and this alternative interpretation are both 
reasonable, and that EPA has discretion to clarify the meaning of this 
statutory provision given the ambiguity in the legislation. As outlined 
below, today's rulemaking (see the revisions to Sec. 70.6(c)(5)) is 
derived from the interpretation contained in the December 1994 notice 
reopening the comment period on the 1993 EM proposal.
6. Consistency with Regulatory Reinvention Efforts
    The approach in this rule lays out broad principles and performance 
criteria for appropriate monitoring, but does not mandate the use of a 
particular technology. The proposal is intended to reflect the 
principles articulated in President Clinton's and Vice President Gore's 
March 16, 1995 report, ``Reinventing Environmental Regulation.'' That 
report established as goals for environmental regulation building 
partnerships between EPA and State and local agencies, minimizing 
costs, providing flexibility in implementing programs, tailoring 
solutions to the problem, and shifting responsibilities to State and 
local agencies. The Agency believes that part 64 meets the goals of the 
report.

[[Page 54906]]

    This approach also is consistent with President Clinton's 
regulatory reform initiatives and EPA's Common Sense Initiative in that 
it focuses on steps to prevent pollution rather than to impose 
unnecessary command and control regulations on regulated sources. The 
approach is based on the assumption that pollution control is an 
integral part of doing business and that owners or operators should pay 
attention to their pollution control operations with the same care they 
do their product operations. The CAM approach emphasizes the role of 
the owner or operator in developing a plan to achieve this goal for 
specific circumstances.

D. Benefits of a CAM Approach and Potential Control Costs

    The EPA believes that monitoring under part 64 can in some 
situations, reduce operating costs. For example, monitoring data can be 
used to increase combustion efficiency in an industrial boiler or to 
increase capture and reuse of solvents at a coating plant. A 1990 study 
by the General Accounting Office entitled ``Air Pollution: Improvements 
Needed in Detecting and Preventing Violations'' (see docket item A-91-
52-VI-I-12) noted several instances in which companies have achieved 
such operating cost reductions. The CAM approach also alerts owners or 
operators that potential control device problems may exist. The owner 
or operator can use this information to target control devices for 
routine maintenance and repair, and reduce the potential for costly 
breakdowns. While benefits may occur to some facilities as the result 
of better awareness of equipment operation, changes in equipment 
operation are not required by part 64.
    Part 64 does not itself have emissions reductions benefits, EPA 
does expect, however, that some sources may have to reduce emissions in 
order to comply with their underlying emissions standards in response 
to monitoring under part 64. EPA expects that some emissions reductions 
may result from sources having to reduce emissions overall, and/or to 
respond to periods of excess emissions more quickly, thus reducing 
their frequency and duration. EPA has not estimated the emissions 
reductions that may result from this; EPA believes these reductions and 
any associated health and welfare benefits are not attributable to part 
64--but to the underlying emissions standards.
    The Agency believes that there is adequate evidence that monitoring 
control performance will assure continuing compliance with applicable 
requirements. Studies conducted by the Agency have shown that control 
device operation and maintenance problems are a significant factor in 
creating excess emissions (see docket items II-A-22 and VI-A-2). In 
addition, these studies have documented that assumptions about 
compliance status are often inaccurate when detailed inspections of 
control devices are conducted (see, for example, docket item VI-A-2). 
Moreover, information included in the Regulatory Impact Analyses (RIA) 
documents that, based on data sheets compiled for all major sources by 
State agency inspectors in fifteen States, approximately 20 percent of 
all major sources have significant compliance problems and there is a 
significant corollary between the adequacy of a source's operation and 
maintenance procedures and compliance risk.
    There will be real costs associated with measures sources may take 
to reduce emissions in order to comply with their underlying emissions 
standards in response to monitoring under part 64. Costs as well as 
emissions reductions benefits will result from sources having to reduce 
emissions overall, and/or to respond to periods of excess emissions 
more quickly, thus reducing their frequency and duration. Such costs 
would be due to increase expenditures for operation and maintenance and 
capital equipment. The EPA has not estimated the cost associated with 
emissions reductions that may result; EPA believes such costs are not 
attributable to part 64--but to the underlying emissions standard.

E. The Relationship of Part 64 to Credible Evidence and Enforcement 
Issues

1. General CAM Enforcement Policy
    As a general matter, the Agency expects that source owners or 
operators will be in compliance with all applicable emission 
requirements if they conform to the requirements of part 64. Further, 
the Agency expects that there will be relatively limited information 
available to override the information provided by the owner or operator 
on an emissions unit's compliance status beyond that provided through 
monitoring that satisfies part 64 or part 70. However, neither these 
expectations nor complete compliance with part 64 will prohibit the 
Agency from undertaking enforcement investigations when appropriate 
under the circumstances, such as when information indicates there are 
conditions that may threaten or result in harm to public health or the 
environment, indicates a pattern of noncompliance, indicates serious 
misconduct, or presents other circumstances warranting enforcement.
2. The Credible Evidence Revisions to 40 CFR parts 51, 52, 60, and 61 
(``The CE Revisions'')
    See the CE Revisions as published in the Federal Register on 
February 24, 1997 (62 FR 8314) for discussion of that rulemaking 
history. During the many public comment periods for the CE Revisions 
and the CAM proposal, the Agency received numerous comments stating 
that the two rules are inextricably connected, impact each other, and 
should be proposed together in order for meaningful public comment from 
interested stakeholders. The Agency reviewed these comments but decided 
to proceed with the CE rulemaking separately from this rulemaking for 
several reasons. First, the Agency believes that there was sufficient 
opportunity for all interested parties to comment on any perceived 
relationship or any substantive issues regarding the proposed credible 
evidence revisions and the CAM proposal before the promulgation of the 
CE Revisions in February, 1997. The Agency released a public draft of 
the CAM approach in September, 1995, and then conducted a public 
meeting in April, 1996, on the credible evidence revisions. The Agency 
also accepted public comments on the credible evidence rulemaking and 
the CAM proposals between September, 1995, and the promulgation of the 
CE Revisions. Thus, all interested parties had the opportunity to 
comment on the two rulemakings and the Agency received numerous 
comments on this topic before the CE Revisions were promulgated. In 
addition, there was also ample opportunity for public comment on any 
perceived relationship after promulgation of the CE Revisions and 
before the finalization of part 64. The Agency released a public draft 
of the CAM approach in August, 1996, and held a public meeting 
regarding the 1996 part 64 Draft. The Agency also reopened the comment 
period on part 64 on April 25, 1997, ( 62 FR 20147) to allow for 
comments on the relationship between part 64 and the CE Revisions. See 
the Response to Comments Document (Part III) at section 14 for the 
Agency's response to these comments. Thus, all interested parties had 
the opportunity to comment on the relationship between part 64 and the 
CE Revisions before each of these rulemakings was promulgated.
    Second, the Agency decided to promulgate the CE Revisions separate 
from part 64 because the two programs are different in scope. The CE 
Revisions

[[Page 54907]]

are not limited to part 64 data or information collected pursuant to a 
part 70 permit generally. Other types of CE could include information 
from monitoring that is not required by regulation (such as monitoring 
conducted pursuant to a consent agreement or a specific section 114 
request) or information from inspections by the permitting authority. 
In addition, the CE Revisions affect all sources regulated by 40 CFR 
parts 51, 52, 60, and 61, not just sources who will be covered by part 
64. Thus, although sources covered by this rulemaking are regulated 
under the provisions amended by the CE Revisions, both the sources 
covered by this rulemaking and the data generated by this rulemaking 
are subsets of the sources and potential credible evidence addressed in 
the CE Revisions. Therefore, it was appropriate for the Agency to 
promulgate these two rulemakings separately. See 63 FR 8314 for a 
discussion of the scope of the CE Revisions.
    Even though the CE Revisions and part 64 rulemakings are distinct 
regulatory actions, there are complementary aspects to the two rules. 
As noted above, consistent with the existing provisions of part 70, the 
CE revisions reiterate that data other than compliance test data can be 
used as a basis for title V compliance certifications. Most 
importantly, the CE rulemaking affects the potential consequences of 
identifying deviations, exceedances or excursions in a compliance 
certification based on data, such as part 64 data, that are from 
sources other than the compliance or reference test method. The CE 
revisions clarify the authority to rely on these data to prove that a 
source is in compliance or that a violation has occurred.
    Finally, the CE Revisions and this rulemaking did not need to be 
promulgated together because these regulations have different statutory 
bases. The Agency promulgated the CE Revisions based primarily on 
section 113(a) of the Act, which authorizes the Agency to bring an 
administrative, civil or criminal action ``on the basis of any 
information available to the Administrator.'' See 62 FR at 8320-23. The 
part 64 regulations, however, respond to the statutory mandates of the 
CAA Amendments of 1990, including but not limited to section 114(a)(3).
3. Potential Enforcement Consequences Related to CAM and CE
    As a general matter, the Agency notes that it intends to apply its 
current enforcement policies in instances where the Agency believes, 
based on a review of CAM data, that a source has violated underlying 
emission limits. During the public comment period, commenters raised 
several issues about the relationship between the proposed part 64 
monitoring information, the CE Revisions, and enforcement of violations 
of the Act. The following discussion generally addresses those 
concerns. See section 14.2 (Part III) of the Response to Comments 
Document (A-91-53-VII-C-3) for responses to specific issues raised.
    First, these commenters suggested that compliance with indicator 
ranges under part 64 should act as a shield to enforcement actions. The 
Agency disagrees. Complete compliance with an approved part 64 
monitoring plan does not shield a source from enforcement actions for 
violations of applicable requirements of the Act if other credible 
evidence proves violations of applicable emission limitations or 
standards. The Agency expects that a unit that is operating within 
appropriately established indicator ranges as part of approved 
monitoring will, in fact, be in compliance with its applicable limits. 
Part 64 does not prohibit the Agency, however, from undertaking 
enforcement where appropriate (such as cases where the part 64 
indicator ranges may have been set improperly and other data such as 
information collected during an inspection provides clear evidence that 
enforcement is warranted).
    Similarly, several commenters stated that if a source owner or 
operator identified excursions or exceedances of the applicable 
indicator ranges and conducted a prompt correction, with or without a 
QIP, then there should be a shield from enforcement for any potential 
violation of an underlying emissions limitation. This is also 
incorrect. If a source owner or operator identifies one or more 
excursions or exceedances of its indicator ranges established under 
part 64, prompt correction of the condition does not establish a 
shield. At the same time, the CAM excursions do not necessarily give 
rise to liability under part 64 or the Act (unless an excursion is 
specifically made an enforceable permit term). The Agency understands 
that many sources operate well within permitted limits over a range of 
process and pollution control device operating parameters. Depending on 
the nature of pollution control devices installed and the specific 
compliance strategy adopted by the source or the permitting authority, 
part 64 indicator ranges may be established that generally represent 
emission levels significantly below the applicable underlying emission 
limit. For this reason, and because the Agency anticipates a wide 
variance in CAM indicator range setting practices, the Agency intends 
to draw no firm inferences as to whether excursions from CAM parameter 
levels warrant enforcement of underlying emission levels without 
further investigation into the particular circumstances at the source. 
Thus, although staying within appropriately established indicator 
ranges gives a reasonable assurance of compliance, excursions from 
indicator ranges do not necessarily indicate noncompliance. The Agency 
may investigate such excursions for possible violations based on the 
general enforcement criteria identified above. A proper and prompt 
correction of the problem causing the excursion or exceedance, with or 
without a QIP, will factor into the Agency's decision on whether to 
investigate a source for potential violations but does not shield the 
source from an enforcement action by the Agency.
    Second, several comments have stated that the use of CAM monitoring 
data as credible evidence to demonstrate the existence of a violation 
would increase the stringency of many standards. Although it is correct 
that the Agency, as well as states, public citizens, and sources, could 
potentially use CAM monitoring data as credible evidence of either 
compliance or noncompliance with an emission standard, the evidence 
could only be used if, as stated in the CE Revisions, the information 
is relevant to whether the source would have been in compliance with 
applicable requirements if the appropriate performance or compliance 
test had been performed. The CE Revisions and the use of CAM data as 
potential credible evidence do not change the stringency of any 
emission standard for the reasons set forth in the preamble to the CE 
Revisions. See 63 FR 8314.
    Finally, it has been suggested during the part 64 and credible 
evidence rulemakings that a Title V permit may be written to limit the 
types of evidence used to prove violations of emissions standards. As 
mentioned in the CE Revisions, even if a Title V permit specifies that 
certain monitoring, CAM or other monitoring, be performed and that this 
monitoring is the sole or exclusive means of establishing compliance or 
non-compliance, EPA views such provisions as null and void. Such an 
attempt to eliminate the possible use of credible evidence other than 
the monitoring specified in a Title V permit is antithetical to the 
credible evidence rule and to section 113(e)(1). If such a provision is 
nonetheless included in a permit, the permit should

[[Page 54908]]

be vetoed to avoid any ambiguity. If the provision is not vetoed, the 
provision is without meaning, as it is ultra vires, that is, beyond the 
authority of the permit writer to limit what evidence may be used to 
prove violations, just as if a permit writer were to attempt to write 
in a provision that a source may not be assessed a penalty of $25,000 
per day of violation for each violation. Evidence that is permitted by 
statute to be used for enforcement purposes, fines that may be levied, 
and any other statutory provisions, may not be altered by a permit.

II. Detailed Discussion of Regulatory Provisions

A. Section 64.1--Definitions

    Section 64.1 defines most of the key terms and phrases used in part 
64. Certain definitions which were contained in Sec. 64.2 of the 1993 
EM proposal have been deleted from the final rule, while other 
definitions from the proposed rule have been considerably revised. In 
addition, a number of new definitions have been added to the final 
rule. The Agency believes these deletions, revisions, and additions 
accomplish the following goals: They reflect changes to the objectives 
and substantive provisions of part 64; they respond to concerns and 
comments made about the definitions in the 1993 EM proposal; and they 
bring part 64 more closely into accord with the regulatory language of 
part 70. The final definitions also reflect changes made in response to 
comments received on the 1995 and 1996 part 64 Drafts. These are 
discussed below.
1. Definitions Deleted from the Final Rule
    The revisions to the substantive provisions of part 64 in the final 
rule have necessitated the deletion of certain definitions set forth in 
Sec. 64.2 of the 1993 EM proposal. In some instances, these definitions 
have been superseded by new terminology relating to the same or similar 
concepts. In other cases, the deleted definitions related to matters 
which are inapplicable to the final rule. The eliminated definitions 
are as follows:
    a. Continuous Compliance and Intermittent Compliance. The 1993 EM 
proposal would have required the use of data from an enhanced 
monitoring protocol to determine and certify whether an affected source 
or emissions unit complied with applicable emission limitations or 
standards and whether such compliance was ``continuous'' or 
``intermittent.'' Section 64.2 of the 1993 EM proposal defined the term 
``continuous compliance'' as requiring the attainment of quality-
assured data from an enhanced monitoring protocol for all required 
periods, the demonstration by such data that an owner or operator has 
complied with the applicable emission limitation or standard during all 
monitored periods, and a demonstration of compliance by any other data 
collected for the purpose of determining compliance during the 
monitored periods if such other data were collected. The 1993 EM 
proposal stated that a source or emissions unit was in ``intermittent 
compliance'' if, during the reporting period, either the data 
availability requirement was not satisfied because insufficient data 
was obtained from the enhanced monitoring protocol, or the owner or 
operator violated the applicable emission limitation or standard 
because a deviation occurred during a period for which no federally-
approved or federally-promulgated excused period applied.
    Many commenters objected to these definitions for various reasons, 
including a contention that EPA had merged the concept of achieving 
continuous compliance with the concept of demonstrating compliance. The 
definitions of continuous compliance and intermittent compliance in the 
proposed rule were also closely tied to the Agency's interpretation of 
section 114(a)(3) of the Act under the 1993 EM proposal. Section 
114(a)(3) directs the Administrator to require certification of 
``whether compliance is continuous or intermittent.'' Under the 1993 EM 
proposal, this language was interpreted as requiring a certification 
that compliance was achieved during all averaging periods for a 
standard, and ``intermittent'' meant that one or more unexcused 
deviations occurred during the certification period. This 
interpretation was also the subject of much public comment. As 
described in greater detail above, the Agency has responded to these 
comments by adopting an alternative interpretation of section 
114(a)(3). The Agency has therefore deleted the EM proposed definitions 
of continuous and intermittent compliance from the final rule. (See 
Section II.K.2. for additional discussion of the interpretation of 
compliance certifications.)
    b. Deviation. The proposed rule stated that a ``deviation'' 
included any condition determined by enhanced monitoring or other 
collected data which identifies that an emissions unit has failed to 
meet an applicable emission limitation or standard. This definition 
included any conditions that either violated an applicable emission 
limitation or standard or would have violated such limitation or 
standard but for a federally-promulgated exemption.
    A number of commenters raised concerns about the proposed 
definition of deviation. Some argued that the proposed definition was 
too closely tied to the violation of an emission limitation or 
standard. These commenters requested clarification that a deviation is 
not necessarily a violation of an emission limitation or standard. 
Other commenters objected to portions of the definition which would 
have allowed a deviation to be based on ``data collected that can be 
used to certify compliance,'' such as the data obtained through a 
voluntary audit. These commenters argued that such a definition created 
a disincentive for owners and operators to engage in certain types of 
self-monitoring.
    The final rule does not refer to ``deviations'' in part 64 and thus 
does not include a definition of ``deviation.'' The 1996 part 64 Draft 
did contain a revised definition of ``deviation'' to be included in the 
part 71 provisions covering the federal operating permits program. This 
definition would have clarified that a deviation is not always a 
violation and that types of events that were to be considered 
deviations included ``exceedances'' and ``excursions'' as defined under 
part 64. The state operating permit programs authorized by part 70 of 
this chapter allow permitting authorities to define the term 
``deviation'' in the context of their individual programs. The 1996 
part 64 Draft did not include a definition of ``deviation'' to be 
included in part 70 because the Agency did not want to restrict the 
power of permitting authorities to define this term.
    Public comments on the 1996 part 64 Draft pointed out that there 
are permitting authorities which define a ``deviation'' as a violation 
of the underlying emission limitation or standard. The provisions in 
the 1996 part 64 Draft which stated that exceedances and excursions are 
to be considered deviations without necessarily being violations 
arguably conflict with those definitions of ``deviation.'' In response 
to these concerns, the Agency has eliminated all references to 
``deviations'' from part 64.
    c. Other Deleted Definitions. The proposed rule contained a 
definition for ``established monitoring.'' This definition applied to 
certain types of monitoring methodologies which had been demonstrated 
to be a feasible means of assessing compliance with emissions 
limitations or standards. The concept of ``established monitoring''

[[Page 54909]]

was used in the monitoring selection process under the 1993 EM 
proposal. As discussed below in Section II.D., these provisions have 
been eliminated in part 64. Because the concept of ``established 
monitoring'' serves no function in the final rule, this definition has 
been deleted.
    The proposed rule defined ``fugitive emissions'' as those emissions 
which could not reasonably pass through a stack, chimney, vent, or 
other functionally-equivalent opening. This definition was necessary 
because Sec. 64.4(d) of the proposed rule would have established 
separate monitoring protocol requirements for fugitive emissions 
monitoring. As discussed below in Section II.B., fugitive emissions are 
not subject to any specific part 64 monitoring requirements. The Agency 
has therefore deleted this definition from the final rule.
    Section 64.4(c) of the 1993 EM proposal established certain 
requirements for owners or operators who sought to use the monitoring 
of process or control device parameters as part of an enhanced 
monitoring protocol. In certain instances, the proposed rule required 
the establishment of a ``demonstrated compliance parameter level'' 
(DCPL) to determine which levels of the parameter being monitored 
correlated with a demonstration of compliance with the applicable 
emission limitation or standard. Under the requirements in the final 
rule, the Agency has modified its approach to parameter monitoring (see 
Section II.C. for a more detailed discussion). Accordingly, the 
definition of ``demonstrated compliance parameter level'' or DCPL has 
been deleted from the final rule.
    Both the terms ``enhanced monitoring'' and ``enhanced monitoring 
protocol'' have been eliminated in the final rule. The 1993 EM proposal 
defined ``enhanced monitoring'' as the methodology used by an owner or 
operator to detect deviations with sufficient representativeness, 
accuracy, precision, reliability, frequency, and timeliness in order to 
determine if compliance is continuous during a reporting period. An 
``enhanced monitoring protocol'' was defined as the monitoring 
methodology and all installation, equipment, performance, operation, 
and quality assurance requirements applicable to that methodology. The 
final part 64 establishes monitoring performance criteria in the body 
of the rule rather than in a definition; thus, the definitions of 
``enhanced monitoring'' and ``enhanced monitoring protocol'' have been 
deleted. The 1996 part 64 Draft included a related concept, the 
``compliance assurance monitoring (CAM) plan,'' which distinguished 
monitoring for units with control devices subject to subpart B of that 
draft rule and monitoring for other units under subpart C of that draft 
rule. Because the final rule does not include subpart C, this term is 
not used in the final rule.
    ``Responsible official'' was defined under the 1993 EM proposal as 
having the same meaning as provided under Sec. 70.2. This term was used 
in Sec. 64.5(c) of the 1993 EM proposal, which required that the 
personal certification of a responsible official be included in each 
enhanced monitoring report. In response to a number of objections to 
this requirement, the Agency has not included a part 64 report 
signature requirement in the final part 64 rule but generally relies on 
part 70 reporting procedures. Thus, there is no need to define 
``responsible official'' in part 64. It should be noted that 
Sec. 70.5(d) outlines the responsible official's duties with respect to 
submitting reports, including part 64 reports.
2. Revised Definitions
    There are a number of definitions that were in the 1993 EM proposal 
that have been revised in the final rule. Some of these revisions are 
relatively minor, such as technical revisions designed to reflect 
changes to the substantive provisions of part 64 or to more closely 
parallel the definitions found in part 70. Other revisions are intended 
to address more significant concerns with the proposed definitions. The 
revised definitions are as follows:
    a. Emission Limitation or Standard and Applicable Requirement. The 
1993 EM proposal defined an ``emission limitation or standard'' as any 
federally enforceable emission limitation, emission standard, standard 
of performance or means of emission limitation as defined under the 
Act. This term is actually a hybrid of several terms used under the 
Act. The proposed definition stated that an emission limitation or 
standard may be expressed as a specific quantity, rate or concentration 
of emissions; as the relationship of controlled to uncontrolled 
emissions (e.g., control efficiency); as a work practice; as a process 
or control device parameter; or as another form of design, equipment, 
operational, or operation and maintenance requirement.
    Section 64.2 of the 1993 EM proposal also defined an ``applicable 
emission limitation or standard'' as any emission limitation or 
standard subject to the requirements of part 64 including: (1) An 
emission limitation or standard applicable to a regulated hazardous air 
pollutant under 40 CFR part 61; or (2) an emission limitation or 
standard applicable to a regulated air pollutant other than a hazardous 
air pollutant under section 112 of the Act, for which the source is 
classified as a major source.
    The definition of ``applicable emission limitation or standard'' 
was closely tied to the applicability provisions of the 1993 EM 
proposal. For example, the separate treatment of hazardous air 
pollutant emissions limitations or standards in the definition followed 
the proposed rule's separate applicability provisions for hazardous air 
pollutants. Those applicability provisions have been significantly 
revised in part 64. Commenters raised concerns that the meaning of the 
term ``applicable emission limitation or standard'' was unclear. The 
Agency agrees that the proposed definitions of ``applicable emission 
limitation or standard'' and ``emission limitation or standard'' could 
be confusing, especially when interpreted in conjunction with the pre-
existing definition of ``applicable requirement'' in part 70. The final 
rule replaces the term ``applicable emission limitation or standard'' 
with the term ``applicable requirement.'' Part 64 states that 
``applicable requirement'' shall have the same meaning as provided 
under part 70. The Agency made this change in the final rule to avoid 
any potential confusion and to bring part 64 into closer agreement with 
the definitions of part 70.
    Part 64 retains the basic definition of ``emission limitation or 
standard'' with several revisions. Several commenters requested 
clarification on the meaning of ``federally enforceable'' in this 
definition. The final rule eliminates the phrase ``federally 
enforceable'' in the definition and defines an emission limitation or 
standard as ``any applicable requirement that constitutes an emission 
limitation, emission standard, standard of performance or means of 
emission limitation * * *'' This adjustment reflects the addition of 
the term ``applicable requirement'' in the final rule. The term 
``applicable requirement'' is used in part 70 permitting to refer to 
the standards, requirements, terms, and conditions that are contained 
in the part 70 permit as federally-enforceable requirements. Thus, the 
reference to ``federally enforceable'' was eliminated because, through 
the permitting process, all ``applicable requirements'' become 
federally enforceable.

[[Page 54910]]

    Additional language in the part 64 definition of ``emission 
limitation or standard'' clarifies that, for purposes of part 64, the 
definition of ``emission limitation or standard'' does not include 
general operation requirements that an owner or operator may be 
required to meet, such as requirements to obtain a permit, to operate 
and maintain sources in accordance with good air pollution control 
practices, to develop and maintain a malfunction abatement plan, or to 
conduct monitoring, submit reports or keep records. As noted below (see 
detailed discussion of Sec. 64.2), requirements of this type generally 
apply to an entire facility. The Agency has specifically excluded such 
requirements so that otherwise unregulated emissions units are not 
inappropriately subject to part 64 monitoring requirements.
    A number of commenters requested that EPA further narrow the 
definition of emission limitation or standard so that it would not 
apply to work practice, design or similar types of requirements. The 
commenters argued that part 64 monitoring for these types of standards 
did not make sense and would be redundant. The Agency disagrees to the 
extent that a control device is used to achieve compliance with these 
types of standards. As discussed in Section II.B., the final rule 
applies only to pollutant-specific emissions units which achieve 
compliance by using a control device. The monitoring is designed to 
document that the control device is properly operated and maintained. 
Many work practice, design or similar standards will not apply to these 
types of units (i.e., with control devices), which addresses many of 
the commenters' concerns. For units that are subject to such 
requirements and that do use a control device (see, e.g., 40 CFR 
60.692-5, which imposes a ``design'' standard that certain emissions be 
controlled by a control device with 95 percent design efficiency), the 
nature of the standard is immaterial to the assessment of whether the 
control device is properly operated and maintained. The Agency notes 
that in the example, the NSPS requires the owner or operator to monitor 
the control device to assure proper operation and maintenance (see 
Sec. 60.695). Part 64 will act in a similar manner.
    b. Part 70/Part 71 Permit. The term ``permit'' as defined in the 
1993 EM proposal meant any applicable permit issued, renewed, amended, 
revised, or modified under part C or D of title I of the Act, or title 
V of the Act. Under the 1993 EM proposal, part 64 would have been 
implemented through both the part 70 operating permits program and the 
preconstruction permits programs developed under parts C and D of title 
I of the Act. Public commenters raised a variety of objections and 
concerns to this proposed implementation structure. The Agency has 
responded to these comments in part by limiting part 64 implementation 
under part 64 to permits covered by title V of the Act.
    To reflect this change in the implementation approach, the Agency 
has replaced the proposed definition of ``permit'' with a definition 
for a ``part 70 or 71 permit.'' Section 64.1 of the final rule states 
that ``part 70 or 71 permit'' shall have the same meaning as provided 
under part 70 (or part 71) of this chapter. The Agency believes this 
definition is consistent with the goal of bringing part 64 definitions 
into closer agreement with their part 70 (or part 71) counterparts.
    The Agency has also added a related definition in part 64. The 
definition of a ``part 70 or 71 permit application'' includes any 
application that is submitted by an owner or operator in order to 
obtain a part 70 or 71 permit, including any supplement to a previously 
submitted application. The Agency believes the addition of this 
definition is necessary because the implementation provisions set forth 
in Sec. 64.3 of part 64 are connected to the submission of a part 70 or 
71 permit application.
    c. Major Source. The 1993 EM proposal defined the term ``major 
source'' as including any major source meeting the definition in 
Sec. 70.2, excluding any hazardous air pollutant (HAP) source included 
in paragraph (1) of that definition. One commenter requested 
clarification of why this definition excluded major HAP sources 
included in the major source definition of part 70. The form of the 
proposed definition was necessary because the 1993 EM proposal treated 
HAP requirements separately from other requirements. For HAP 
requirements, the 1993 EM proposal would have applied to any source 
required to obtain a part 70 operating permit or a preconstruction 
permit under part C or D of title I of the Act and not just to ``major 
sources.'' As discussed below, the applicability provisions of part 64 
have been substantially modified in the final rule such that there are 
no separate applicability provisions for HAP requirements (see Section 
II.B.). In the final rule, the definition of ``major source'' has been 
revised to reflect these changes. Part 64 simply states that ``major 
source'' shall have the same meaning as provided in part 70.
    The U.S. Small Business Administration (SBA) submitted for 
discussion at the September 10, 1996 meeting a proposal to retain, in 
part 64, EPA's current practice of excluding from major source status 
those sources whose actual emissions are less than 50 percent of the 
major source threshold. SBA apparently was referring to EPA's policy 
issued in January 1995 to establish a two-year (extended until July 31, 
1998) transition policy that guides EPA in applying the definition of 
``major source'' in part 70. Because part 64 relies on part 70's 
definition of ``major source,'' SBA's concern is met. As long as that 
policy remains in effect, it will be relevant to determining 
applicability under part 64. See also National Mining Association 
versus U.S. EPA, 59 F.3d 1351 (D.C. Cir. 1995).
    d. Other Part 70 Related Definitions. Section 64.2 of the proposed 
rule contained a definition for ``potential to emit'' which tracked the 
language of the part 70 definition of ``potential to emit'' with 
technical edits to reflect the 1993 EM proposal's focus on emissions 
units as opposed to the focus on major sources in part 70. The text of 
the proposed rule did not make it clear, however, that part 70 was the 
source for the proposed definition. Under part 64, ``potential to 
emit'' is explicitly defined as having ``the same meaning as provided 
under part 70 of this chapter, provided that it shall be applied with 
respect to an `emissions unit' as defined under this part in addition 
to a `stationary source' as provided under part 70 of this chapter.'' 
Although the text of the definition has been changed, the meaning of 
``potential to emit'' in the final rule is effectively the same as in 
the proposed rule. The Agency made these revisions to clarify the 
connection of this term with the definitions of part 70.
    The 1993 EM proposal defined ``emissions unit'' as any part or 
activity of a source that emits or has the potential to emit any 
regulated air pollutant for which an emission limitation or standard 
had been established. This definition was a modification of the 
definition of ``emissions unit'' set forth in part 70. The Agency 
received a variety of public comments on this definition. One commenter 
recommended using the part 70 definition of ``emissions unit'' in part 
64. Several other commenters expressed concern over the use of the 
phrase ``any part or activity'' in the definition, stating that the 
definition was not clear as to whether an emissions unit is a single 
piece of equipment or a group of multiple units located together within 
a source. In response to these comments, the definition of ``emissions 
unit'' has been revised in the final rule to have the same meaning as 
provided under part

[[Page 54911]]

70. This approach clarifies potential ambiguity in the definition by 
relying on the established part 70 definition of the term and brings 
part 64 into closer agreement with the provisions of the operating 
permits program thorough which part 64 will be implemented.
    The 1993 EM proposal contained a definition of ``permitting 
authority'' which tracked the language of the part 70 definition of 
``permitting authority'' with technical edits to reflect the proposed 
EM rule's implementation through both title V permitting programs and 
title I preconstruction permit programs. The text of the proposed rule 
did not make it clear, however, that part 70 was the source for the 
proposed definition. In addition, the final rule is not implemented 
through title I preconstruction permits. The Agency has therefore 
revised the definition of ``permitting authority'' to have expressly 
the same meaning as provided under part 70.
3. Definitions Added in the Final Rule
    Many of the definitions in Sec. 64.1 of the final rule have been 
added to reflect changes in the substantive requirements of part 64 
monitoring under part 64. These definitions are generally addressed in 
the detailed discussion of the appropriate substantive sections of the 
final rule. The following discussion provides a brief overview of some 
key terms added to the definitions section of the final rule.
    The Agency has added definitions for the terms ``monitoring'' and 
``data'' to the final rule. The rule defines ``monitoring'' as any form 
of collecting data on a routine basis to determine or otherwise assess 
compliance with emission limitations or standards. The rule also 
includes a non-exclusive list of data collection techniques which may 
be considered appropriate monitoring under part 64. This list is 
similar to the list included in Sec. 64.6 of the 1993 EM proposal with 
minor changes in response to comments on that section. ``Data'' is 
defined as the results of any type of monitoring or compliance 
determination method. Some commenters had raised concerns that the use 
of the term ``data'' in the substantive provisions of proposed part 64 
reflected a bias toward instrumental monitoring methods. The Agency 
believes that by adding these two definitions, the final rule reflects 
the Agency's intent that a wide variety of information and means of 
collecting information potentially can be used to satisfy the 
requirements of part 64.
    Definitions for the terms ``exceedance'' and ``excursion'' have 
been added to the final rule. These terms are closely related. Section 
64.1 defines an ``exceedance'' as a condition detected by monitoring 
which provides data in terms of an emission limitation or standard and 
which indicates that emissions or opacity are greater than that 
limitation or standard, consistent with the applicable averaging 
period. An ``excursion'' is defined as a departure from an indicator 
range established as part of part 64 monitoring, also as consistent 
with the applicable averaging period. As discussed above, the 1996 part 
64 Draft would have stated that an exceedance or excursion would be 
considered a deviation in the part 70 compliance certification. This 
statement has been removed in response to comments that such conditions 
should not necessarily constitute deviations, especially since some 
permitting authorities equate a deviation with a violation. See Section 
II.K.2. of this preamble for additional discussion on the status of 
excursions for a part 70 compliance certification. The 1996 part 64 
Draft also omitted reference to the applicable averaging period. That 
omission has been corrected in the final rule.
    The final definition added to the final rule describes the meaning 
of a ``predictive emissions monitoring system (PEMS).'' Several 
commenters to the 1993 EM proposal suggested that a definition for this 
term should be added to part 64. The Agency agrees with this suggestion 
and has included an appropriate definition in Sec. 64.1 of the final 
rule. This definition is included in the final part 64 rule because 
Sec. 64.3(c) sets forth special criteria for the use of predictive 
monitoring systems when employed to fulfill part 64 monitoring 
requirements. The same section also provides special criteria for the 
use of continuous emission or opacity monitoring systems. Because these 
latter types of systems are well understood, no explicit definition was 
considered necessary for purposes of part 64.

B. Section 64.2--Applicability

1. Overview
    The applicability provisions in Sec. 64.2 reflect EPA's decision to 
focus part 64 requirements on units that use control devices to achieve 
compliance. The types of emission exceedance problems that can arise 
from poor operation and maintenance of a control device can be severe 
and represent a significant compliance concern. Moreover, although 
units with control devices represent a smaller percentage of the 
overall number of emissions units than other units, these controlled 
units represent a disproportionate share of the overall potential 
emissions from all emissions units. By concentrating the requirements 
of part 64 on these units with control devices, the Agency has focused 
the rule on units that represent a significant portion of the overall 
potential emissions regulated under the Act and that are generally most 
likely to raise compliance concerns.
    The Agency notes that the term ``pollutant-specific emissions 
unit,'' defined in Sec. 64.1, is used in part 64 to clarify that 
applicability is determined with respect to each pollutant at an 
emissions unit separately. For example, a coal-fired boiler emitting 
through a single stack could constitute several pollutant-specific 
emissions units, such as for particulate matter, SO<INF>2</INF>, 
NO<INF>X</INF>, and CO. This term is used throughout the remainder of 
this document where appropriate.
2. Significant Changes in the Applicability Threshold and Related 
Definitions
    Section 64.2(a) of the final rule requires the owner or operator to 
apply part 64 to significant pollutant-specific emissions units that 
use control devices to achieve compliance at major sources subject to 
part 70 permit requirements. The issues raised with respect to 
applicability during the development of the rule are described below.
    a. Applicability Options Presented in the 1993 EM Proposal. The 
preamble to the 1993 EM proposal solicited comments on five options for 
determining which emissions units would be subject to enhanced 
monitoring requirements under part 64. These options set the threshold 
for applicability based on each unit's potential to emit the regulated 
air pollutant(s) for which a stationary source is classified as a major 
source. Option 1 set no percentage threshold, making all units with 
applicable requirements for the pollutant for which a source is major 
subject to part 64 monitoring. Options 2, 3, 4, and 5 would have made 
part 64 applicable to all units that have the potential to emit 
pollutants in an amount equal to or greater than 10, 30, 50, and 100 
percent of the applicable major source definition, respectively. The 
1993 EM proposal incorporated Option 3, setting the threshold at 30 
percent. Under the proposed rule, the source of an air pollutant which 
is defined as being major at 100 tons per year would be required to 
conduct enhanced monitoring at all emissions units within its facility 
that had the potential to emit 30 tons or more of the pollutant per 
year.

[[Page 54912]]

    Applicability under the 1993 EM proposal was based on an emission 
unit's ``potential to emit.'' The proposal defined this term as an 
emission unit's maximum capacity to emit a regulated air pollutant 
under the unit's physical and operational design, taking into account 
such operating restrictions and control equipment as constitute 
federally-enforceable limitations. As noted above, the 1993 EM proposal 
also would have applied only to the pollutants for which a source is 
major. The 1993 EM proposal solicited comment on the applicability 
approach in the proposed rule, and specifically noted that one other 
option would be to use uncontrolled emissions rather than potential to 
emit to determine part 64 applicability. The Agency noted that such an 
approach arguably would better address the units with the greatest 
environmental risk. This request for comment was accompanied by an 
assertion that in a monitoring rule such as part 64, it may be 
appropriate to use a different definition of potential to emit than EPA 
has used for other purposes.
    b. Final Part 64 Applicability Provisions. In response to the many 
comments received on the 1993 EM proposal, the Agency modified part 64 
to bring about the CAM approach including a somewhat different approach 
to applicability. The Agency received numerous public comments on the 
applicability provisions of the 1993 EM proposal. Relatively few 
commenters supported the Option 3 (30 percent) threshold. Many of the 
comments critical of Option 3 argued that the benefits of increased 
pollutant monitoring obtained by covering additional emissions units at 
the 30 percent threshold was far outweighed by the additional costs and 
burdens of implementation at that threshold. Most industry and many 
State and local commenters supported Option 5 or a higher threshold. 
Many of the commenters also recommended that EPA exempt various types 
of units, especially uncontrolled units that are subject to design, 
work practice, or similar operational restrictions. In addition, a 
number of commenters suggested alternative approaches to determining 
the applicability threshold of part 64. Industry commenters generally 
favored the focus of the 1993 EM proposal on the pollutants for which a 
source is a major, while environmental groups opposed that approach.
    The final part 64 retains the basic concept of an applicability 
threshold as contained in the 1993 EM proposal, but also narrows the 
focus so that part 64 applies only to those pollutant-specific 
emissions units that use a control device to achieve compliance with an 
applicable emission limitation or standard. In addition, units using 
control devices must have potential pre-control device emissions equal 
to or greater than 100 percent of the applicable major source 
definition to be subject to part 64. Since part 64 applies its size 
threshold only to the proportionally small number of emissions units 
that use control devices, the number of units required to meet part 64 
monitoring requirements is lower than would have been subject to the 
1993 EM proposal. The final RIA estimates that part 64 will affect 
fewer than 27,000 units as compared to the over 35,000 units which EPA 
had estimated would be affected under the 1993 EM proposal.
    For part 64 to apply, Sec. 64.2(a) specifies that a pollutant-
specific emissions unit must meet the following three criteria: (1) The 
unit must be subject to an emission limitation or standard for the 
applicable regulated air pollutant (or a surrogate of that pollutant); 
(2) the unit must use a control device to achieve compliance with an 
emission limitation or standard; and (3) the unit must have ``potential 
pre-control device emissions'' in the amount, in tons per year, 
required to classify the unit as a major source under part 70.
    i. Emission Limitation or Standard Criterion. For the first 
criterion, the Agency notes that part 64 applies only if an applicable 
emission limitation or standard applies because the purpose of part 64 
is to provide a reasonable assurance of compliance with such 
requirements. Numerous comments on the 1993 EM proposal supported EPA's 
position that part 64 should apply only if an underlying applicable 
emission limitation or standard applies, but many commenters suggested 
that the final rule should contain explicit language concerning the 
necessity for an underlying standard to trigger part 64 applicability. 
The commenters believed inclusion of such language was critical because 
a part 70 operating permit will be required to include units without 
applicable requirements, and part 70 permits will be required for 
sources without any applicable requirements (so-called ``hollow 
permits''). Their concern was that part 64 could be interpreted as 
applying to units and sources of this type and that determining 
compliance with the rule under such an interpretation would be 
exceedingly difficult. The Agency agrees that the rule should clearly 
state that part 64 applies only where a federally enforceable emission 
limitation or standard applies and thus has added this first criterion 
to the applicability determination. The Agency also notes that the 
applicability provisions in part 64 include a ``surrogate'' of a 
regulated air pollutant to address situations in which the emission 
limitation or standard is expressed in terms of a pollutant (or other 
surrogate) that is different from the regulated air pollutant that is 
being controlled. A common example would be emission limits expressed 
in terms of particulate matter and opacity rather than PM-10. Another 
example would be an emission limit expressed as a control device 
operating requirement rather than in terms of the applicable regulated 
air pollutant.
    ii. Control Devices Criterion. Second, the final rule applies only 
to pollutant-specific emissions units that rely on a control device to 
achieve compliance. The final rule provides a definition of ``control 
device'' that reflects the focus of part 64 on those types of control 
devices that are usually considered as ``add-on controls.'' This 
definition does not encompass all conceivable control approaches but 
rather those types of control devices that may be prone to upset and 
malfunction, and that are most likely to benefit from monitoring of 
critical parameters to assure that they continue to function properly. 
In addition, a regulatory obligation to monitor control devices is 
appropriate because these devices generally are not an inherent part of 
the source's process and may not be watched as closely as devices that 
have a direct bearing on the efficiency or productivity of the source.
    The control device definition is based on similar definitions in 
State regulations (see, e.g., North Carolina Administrative Code, title 
15A, chapter 2, subchapter 2D, section .0101 (definition of ``control 
device''); Texas Administrative Code, title 30, section 101.1 
(definition of ``control device''). The definition is in contrast to 
broader definitions of ``control device,'' ``air cleaning equipment,'' 
``control measure,'' or similar terms included in some States' 
regulations (see, e.g., Codes, Rules, and Regulations of the State of 
New York, title 6, chapter III, section 200.1 (definition of ``air 
cleaning device'' or ``control equipment'')). These broader definitions 
often include any method, process or equipment which removes, reduces 
or renders less noxious air contaminants released to the ambient air. 
Those types of controls could include material substitution, process 
modification, operating restrictions and similar types of controls. The 
definition in part 64 relies on the narrow interpretation of a control 
device that focuses on control

[[Page 54913]]

equipment that removes or destroys air pollutants.
    Certain NSPS and NESHAP regulations also have targeted definitions 
of ``control device'' or ``add-on control device'' that apply to the 
specific type of affected facility covered by the applicable NSPS or 
NESHAP subpart (see, e.g., 40 CFR 60.581, 60.670, 60.691, 60.731, 
61.171, 61.241, 63.161, 63.561, and 63.702). The part 64 control device 
definition generally is consistent with these prior Agency definitions, 
but without language targeted to a particular affected facility type.
    The Agency notes that EPA's Aerometric Information Retrieval System 
(AIRS) contains a list of various air pollution control equipment codes 
that address a wide variety of possible control methods, processes and 
equipment; this list includes both active control devices and other 
types of controls. In conjunction with the release of the 1996 part 64 
Draft, the Agency placed in the docket (item VI-I-3) a document that 
reflects EPA's position on which of those equipment codes refer to a 
``control device'' as defined in the 1996 part 64 Draft and which refer 
to other types of controls. The Agency continues to believe that this 
document provides an appropriate list of the types of equipment which 
may constitute control devices.
    For the final part 64 rule, the control device definition has been 
revised in response to public comments. In the discussion document 
accompanying the 1996 part 64 Draft, the Agency solicited comment on 
the appropriateness of the definition of control device and received 
numerous comments and requests for additional clarifications. 
Generally, commenters felt that the control device definition in the 
1996 part 64 Draft was overly broad and that additional language was 
needed to clarify that EPA does not intend the rule to apply to 
inherent process equipment such as certain types of recovery devices.
    The final rule defines a control device as ``equipment, other than 
inherent process equipment, that is used to destroy or remove air 
pollutant(s) prior to discharge to the atmosphere.'' Thus, the Agency 
has specifically excluded inherent process equipment from the control 
device definition in the final rule. The EPA suggested in the 
discussion document accompanying the 1996 part 64 Draft a list of three 
criteria that would be used to distinguish inherent process equipment 
from control devices:
    (1) Is the primary purpose of the equipment to control air 
pollution?
    (2) Where the equipment is recovering product, how do the cost 
savings from the product recovery compare to the cost of the equipment?
    (3) Would the equipment be installed if no air quality regulations 
are in place?

(See letter from David Solomon, EPA, to Timothy J. Mohin, Intel 
Government Affairs, dated November 27, 1995. Included in the docket as 
Item VI-C-14.)
    The Agency received a number of comments on these criteria, some of 
which supported including the criteria in the rule and others of which 
suggested other approaches. Based on the comments received, the final 
rule defines ``inherent process equipment'' as ``equipment that is 
necessary for the proper or safe functioning of the process, or 
material recovery equipment that the owner or operator documents is 
installed and operated primarily for purposes other than compliance 
with air pollution regulations.'' If equipment must be operated at an 
efficiency higher than that achieved during normal process operations 
in order to comply with applicable requirements, that equipment will 
not qualify as inherent process equipment. In addition, the control 
device definition has been revised to include a list of several control 
techniques that do not constitute ``control devices'' as defined in 
part 64.
    Finally, the definition also makes clear that part 64 does not 
override definitions in underlying requirements that may provide that 
certain equipment is not to be considered a control device for 
pollutant-specific emissions units affected by that regulation. 
Although not subject to part 64, an example of this type of provision 
is Sec. 63.111 in subpart G to 40 CFR part 63 (NESHAP requirements for 
Synthetic Organic Chemical Manufacturing Industry for Process Vents, 
Storage Vessels, Transfer Operations, and Wastewater). The definition 
in that section states that recovery devices used in conjunction with 
process vents and primary condensers used in conjunction with a steam 
stripper do not constitute ``control devices.'' Certain commenters 
asserted that part 64 should not override these types of existing rules 
and EPA agrees. The Agency notes, however, that if an emissions unit is 
regulated for another pollutant, and the control device also is used to 
comply with a limit that applies to that second pollutant, the 
equipment will be considered a ``control device'' for the second 
pollutant unless the standards for the second pollutant also explicitly 
establish that the equipment is not a control device.
    The final rule also includes a definition of a ``capture system'' 
because the rule requires, where applicable, monitoring of a capture 
system associated with a control device. The monitoring requirements 
for control devices extend to capture systems as well because they are 
essential to assuring that the overall emission reduction goals 
associated with the control device are achieved. See Section II.C., 
below. The Agency notes that duct work, ventilation fans and similar 
equipment are not considered to be a capture system if the equipment is 
used to vent emissions from a source to the atmosphere without being 
processed through a control device. For instance, roof vents that 
remove air pollutants from inside a building but do not transport the 
pollutants to a control device to reduce or destroy emissions would not 
be subject to the rule.
    The Agency notes that some commenters, especially environmental and 
other public interest organizations, opposed limiting the applicability 
of part 64 to emissions units that rely on control devices. They argued 
that other significant emissions units with other types of control 
measures, such as low NO<INF>X</INF> burners or similar combustion 
modification controls, should be subject to part 64 requirements.
    Low NO<INF>X</INF> burner technology and certain other types of 
combustion control measures are not included in the definition of 
``control device'' in the final rule. For most large emissions units 
that employ such measures, such as utility boilers, separate applicable 
requirements already require the use of CEMS or similar monitoring for 
such units. Under part 70, that monitoring will have to be included in 
the permit and considered in certifying compliance with applicable 
requirements. Some types of combustion units (e.g., package boilers) 
that may use low NO<INF>X</INF> burner technology do not use the same 
types of technology used by utility and large industrial boilers. The 
technology used for many units with automatic combustion control does 
not provide significant operational flexibility that could afford the 
owner or operator with an opportunity or incentive to manipulate 
NO<INF>X</INF> control levels. (See docket item A-91-52-VI-A-9) For 
these types of units, the recordkeeping of regular inspection and 
maintenance of the low NO<INF>X</INF> burners (e.g., annular flow ratio 
adjustment settings, burner replacement, portable instrument readings, 
etc.) in combination with periodic checks of emission levels with 
appropriate test methods, as necessary, are very likely sufficient to 
ensure that the unit is being operated in a manner

[[Page 54914]]

consistent with good air pollution control practices and that the low 
NO<INF>X</INF> technology continues to reduce emissions at least to the 
level of the standard. The general monitoring requirements in part 70 
are adequate to assure that this type of appropriate monitoring is 
employed.
    For these reasons, EPA believes that monitoring for this control 
technology is best addressed through part 70 periodic monitoring 
requirements and not through expansion of part 64 to units with these 
types of control measures. Of course, if there are particular units 
which raise a significant continuous compliance concern, such as units 
with an historically poor compliance history, the permitting authority 
can require more detailed monitoring under the general part 70 
monitoring provisions given that the permit must include appropriate 
monitoring for assuring compliance with the permit. In those cases, 
permitting authorities may want to consider elements of part 64 as 
potentially appropriate, but they would not be bound to satisfy each 
element of part 64.
    iii. Potential Pre-control Device Emissions Criterion. Finally, for 
the third criterion for applicability, Sec. 64.2(a) relies on the 
concept of ``potential pre-control device emissions.'' This term has 
the same meaning as ``potential to emit,'' except that any emission 
reductions achieved by the control device are not taken into account, 
even if the owner or operator generally is allowed to do so under the 
regulatory definition of ``potential to emit.''
    The Agency first notes that numerous commenters expressed 
objections to the 1993 EM proposal's definition of potential to emit, 
believing the definition resulted in unrealistically high emissions 
numbers. The EPA notes that, contrary to beliefs expressed in many of 
those comments, that definition does take into account enforceable 
operating hour restrictions, throughput restrictions, control system 
efficiency factors, and similar enforceable restrictions. The Agency 
also points out that the same definition has been used in the part 70 
operating permits program as well as the part 63 NESHAP general 
provisions.
    The Agency also notes that the majority of commenters did favor the 
use of potential to emit over uncontrolled emissions because the latter 
approach would not take into account any emissions reductions achieved 
through any means. However, the 1993 EM proposal noted that EPA was 
considering basing applicability on uncontrolled emissions and the 
potential pre-control emissions approach was suggested subsequently by 
State and local agencies (see docket items VI-D-42 and 49) during 
further consideration of part 64 options. As noted in the discussion 
document accompanying the 1996 part 64 Draft, the Agency agrees with 
this approach and believes that excluding the assumed efficiency of the 
control device from the calculation of potential to emit for purposes 
of part 64 applicability provides an appropriate means of 
distinguishing between units based on environmental significance. It 
allows the Agency to distinguish between units based on their true size 
and based on the degree of control required to achieve compliance. The 
Agency notes that this approach does take into account all federally-
enforceable emissions reductions except for those resulting from 
control devices (e.g., emission reductions that occur as a result of 
operating hour or throughput restrictions would be taken into account 
in determining potential pre-control device emissions).
    Many commenters objected to the reliance on potential pre-control 
device emissions, primarily because the use of the potential pre-
control device emissions threshold would result in too many units being 
subject to the rule. Some commenters noted that the 1993 EM proposal 
similarly had requested comment on the use of uncontrolled emissions, 
and that the comments strongly objected to that idea.
    The Agency first notes that, contrary to some commenters' 
assertions, EPA estimates that the final rule will apply to fewer units 
than the 1993 EM proposal because the final rule only applies to the 
proportionally small number of emissions units that use equipment 
meeting the ``control device'' definition. The final RIA estimates that 
fewer than 27,000 pollutant-specific emissions units will be subject to 
part 64, whereas the 30 percent option in the 1993 EM proposal would 
have covered over 35,000 such units. The EPA has also delayed 
implementation for those units subject to the rule that have the 
``potential to emit'' (post-control device) less than the major source 
threshold. This delayed implementation will reduce the burdens of part 
64 on the initial round of part 70 permitting. The Agency feels that 
these changes should alleviate the commenters' concerns and that 
further reductions in the number of units to which the rule applies are 
not appropriate.
    The CAM approach is necessarily concerned with significant, 
controlled units even if the potential to emit after the control device 
is low. The reason for covering these units is two-fold. First, part 64 
monitoring will be designed to detect long-term under-performance of 
control devices that periodic evaluations such as stack tests may be 
unable to document. For example, a unit may have the potential to emit 
20 tons per year after a control device which is required to operate 
with a 99 percent control efficiency. The pre-control device potential 
to emit for that unit is 2,000 tons per year; if the required control 
device efficiency is 99.9 percent, that figure increases to 20,000 tons 
per year. If the long-term actual control performance of that device 
decreases to 95 percent, the actual emissions could increase to 100 or 
1000 tons per year, respectively. Part 64 is aimed first at addressing 
this type of long-term, significant loss of control efficiency that can 
occur without complete failure of a control device. The second type of 
problem is short-term complete loss of control. As indicated in some of 
the comments, for many types of control devices this type of problem 
could be detected after the fact with monitoring less detailed than 
part 64. However, the goal of air pollution control is to prevent these 
types of problems before they occur, if possible, at a reasonable cost. 
The EPA believes that part 64 in many instances can be designed to 
provide early indications of control equipment problems that could be 
addressed prior to such catastrophic failures. For these reasons, EPA 
believes that the use of pre-control device potential to emit is a 
rational basis on which to evaluate whether specific units should be 
subject to part 64.
    Some comments on the 1996 part 64 Draft also objected to the 
potential pre-control device emissions threshold based on the argument 
that the creation of a new size calculation that source owners or 
operators must perform to determine applicability will cause confusion 
and result in additional burdens. The Agency disagrees since owners 
will simply need to remove the design efficiency of the control device 
from the calculation of the applicable unit's potential to emit. 
Potential pre-control emissions will otherwise be calculated in exactly 
the same way as potential to emit. The two figures will both factor in 
enforceable operational restrictions, so only the effect of the control 
device's efficiency, a factor which has to be quantified for 
determining the standard meaning of ``potential to emit,'' will be 
treated differently.
    Commenters also noted that part 64 would expand the 1993 EM 
proposal by not limiting applicability to those pollutants for which 
the source is major. The final rule does limit applicability to

[[Page 54915]]

the pollutants for which a pollutant-specific emissions unit would be 
major except for the emissions reductions assumed to occur as a result 
of a control device. As explained above, EPA believes that the focus of 
the rule on the potential to emit of units prior to a control device is 
an appropriate screening tool to determine which units should be 
monitored under part 64. For that reason, the focus of the 1993 EM 
proposal on major pollutants only would be inappropriate. In addition, 
as some commenters pointed out in response to the proposed rule, the 
Agency typically does not focus on only the major pollutants even where 
applicability of a program is focused solely on whether a source is a 
major source.
    Finally, EPA believes it would be irrational to continue to focus 
solely on the pollutants for which a source is major when the Agency is 
focusing on units that have installed control devices. For instance, a 
source could be ``major'' for NO<INF>X</INF> with no NO<INF>X</INF> 
control devices (and even no NO<INF>X</INF> requirements in an 
attainment area) but have a unit with the potential to emit 20 tons of 
particulate matter after a control device that has a rated removal 
efficiency of 99.9 percent. The post-control particulate potential to 
emit from this particular emissions unit would be less than the major 
source threshold of 100 tons/year; however, the precontrol potential to 
emit of 20,000 tons/year of particulate matter emissions would be 
greater than the 100 tons/year major source threshold. As noted in the 
example discussed above, small decreases in efficiency of that control 
device could lead to actual emission increases significantly above the 
major source threshold. Thus, while the source in this example may not 
have the potential to emit particulate matter (taking into account the 
control device) in amounts sufficient for the source to be classified 
as a major source for particulate matter, the pollutant-specific 
emissions unit for particulate matter, not for NO<INF>X</INF>, in this 
example is clearly one which the Agency believes should be subject to 
part 64.
    Other commenters questioned whether the applicability provisions 
were self-implementing. They argued that unit-by-unit negative 
declarations would be highly burdensome. The Agency agrees and part 64 
does not require that owners or operators justify in a permit 
application why part 64 is not applicable, or that owners or operators 
apply for exemptions. However, the Agency notes that the permitting 
authority can request further explanation as to how a source owner or 
operator determined that part 64 did or did not apply for any 
pollutant-specific emissions unit for which there may be an issue about 
applicability. In addition, an owner or operator that wishes to take 
advantage of the exemption for certain municipally-owned utility units 
will have to provide the documentation required to satisfy that 
exemption (see the following discussion of this exemption).
3. Development of the Exemption Provisions
    Part 64 exempts owners or operators with respect to certain 
emission limitations or standards for which the underlying requirements 
already establish adequate monitoring for the emission limits being 
monitored, and with respect to certain municipally-owned utility units.
    a. Exemptions in the 1993 EM proposal. The 1993 EM proposal 
established exemptions for the following types of emission limits:
    --Emission limitations or standards under the NESHAP program 
(pursuant to section 112 of the Act), except for standards established 
in part 61. This exemption reflected the Agency's intent that the 
provisions of part 63, the MACT standards, will include appropriate 
enhanced monitoring provisions pursuant to the authority in section 
114(a)(3) of the Act.
    --Stratospheric ozone protection requirements under title VI of the 
Act. The type of requirements that apply under that program are 
significantly different than typical emission limitations or standards, 
and the appropriate monitoring for such requirements will be handled 
under regulations implementing those requirements. The exemption is 
unchanged from the proposed rule but for a technical correction 
(substituting title VI of the Act for the original reference to section 
603).
    --Acid Rain Program emission limits under title IV of the Act. The 
Acid Rain monitoring requirements under 40 CFR part 75 already 
establish all appropriate compliance assurance monitoring for such 
requirements. The exemption is unchanged from the proposed rule but for 
a technical correction (to include emission limits applicable to opt-in 
units under section 410 of the Act).
    --NESHAP standards for asbestos demolition and renovation projects. 
These sources are exempt under part 70 and are not required to obtain 
operating permits.
    --NSPS standards for residential wood heaters. These sources are 
also exempt under part 70 and are not required to obtain operating 
permits.
    b. Exemptions in the Final Rule. Issues raised by comments on the 
1993 EM proposal prompted EPA to include certain additional exemption 
provisions in the final part 64 rule. The exemptions that were changed 
or added are:
    --Emission limitations or standards under the NSPS program that are 
proposed after November 15, 1990. This expands on the proposed rule, 
which provided for only the NESHAP exemption. Commenters suggested that 
EPA exempt all NSPS, arguing that existing NSPS contain enhanced 
monitoring requirements. The EPA disagrees that this is the case for 
all NSPS. Existing monitoring of covered units and sources under some 
NSPS may be sufficient to meet part 64 requirements; however, the 
question of sufficiency of any particular monitoring requirement from a 
non-exempt standard will have to be determined in accordance with the 
requirements of part 64. Future federal rulemakings, including NSPS 
rulemakings, will satisfy the monitoring requirements of titles V and 
VII of the 1990 Amendments (see preamble to 40 CFR part 70, 57 FR 
32278, July 21, 1992). The EPA intends to focus on including methods 
for directly determining continuous compliance in these new federal 
rulemakings where such methods are feasible. Only where such approaches 
are not feasible would the Agency consider using an approach similar to 
the CAM approach in such requirements. Since there will be no gaps in 
their monitoring provisions, EPA exempts future NSPS as well as NESHAP 
standards. The Agency notes that this exemption does not apply to State 
emission limits or standards developed under section 111(d) of the Act.
    --Emission limits that apply solely under an emissions trading 
program approved or promulgated by EPA and emission cap requirements 
that meet the requirements of Sec. 70.4(b)(12) or Sec. 71.6(a)(13)(iii) 
are exempt from part 64. This exemption was developed in response to 
comments received on a provision in the 1993 EM proposal which made 
certain ``group[s] of emissions units at a major source'' subject to 
enhanced monitoring requirements. The 1993 EM proposal's preamble 
suggested that this provision applied to emissions units involved in 
some form of ``bubbling'' or trading plan within a single facility as 
well as to fugitive emission points for which compliance is evaluated 
on a process-wide or facility-wide basis.
    The EPA received many comments on the 1993 EM proposal that opposed 
applying enhanced monitoring to

[[Page 54916]]

groups of emissions units. Several industry commenters believed that 
applying part 64 to groups of emissions units would be too inclusive 
and would apply enhanced monitoring requirements to emissions units 
that otherwise would fall below the applicability threshold. Other 
commenters predicted that applying enhanced monitoring to groups of 
emissions units would discourage source owners or operators from 
participating in emissions trading, aggregating, or similar programs. 
Some industry representatives and State and local agencies also 
recommended providing an exemption in part 64 for source owners or 
operators who participate in programs such as RECLAIM in California's 
South Coast Air Quality Management District.
    The final part 64 rule addresses these concerns in a number of 
ways. First, both emission limits that apply solely under an emissions 
trading program approved or promulgated by EPA and emission caps that 
meet the requirements of Sec. 70.4(b)(12) or Sec. 71.6(a)(13)(iii) are 
explicitly exempt from part 64 under Sec. 64.2(b)(1)(iv) and (v). By 
their nature, these types of standards require methods to confirm 
trades or to calculate overall compliance with the cap, taking into 
account the contribution of emissions from all covered units. These 
types of emission limits also often cover all emissions units at a 
facility, including those with extremely low amounts of emissions, 
those without control devices, and those that are not subject to other 
applicable requirements. Because of the need to consider the 
interrelationships among units covered by this type of requirement, the 
type of monitoring in part 64 would not be appropriate. Instead, the 
Agency believes that the existing requirements for monitoring 
compliance with such standards should be followed.
    For instance, the requirements for statutory economic incentive 
programs (40 CFR 51.490--.494) specify the quantification methods that 
must be included as part of any SIP economic incentive program 
developed pursuant to sections 182(g)(3), 182(g)(5), 187(d)(3), or 
187(g) of the Act. In addition, EPA has proposed revisions to 
Sec. 70.4(b)(12) to clarify that emission caps must include 
``replicable procedures and permit terms that ensure the emissions cap 
is enforceable and trades pursuant to it are quantifiable and 
enforceable.'' (59 FR 44460, August 29, 1994). These provisions 
highlight the need to include as part of any emission trading or cap 
requirement the appropriate methods for quantifying emissions and 
assuring that the trade or cap limitation is enforceable. The Agency 
believes that the imposition of part 64 on these types of standards 
would not provide any additional benefit.
    In addition, other groups of emissions units are generally not 
subject to monitoring requirements under part 64. Part 64 requirements 
apply only to individual pollutant-specific emissions units that use a 
control device to achieve compliance and whose pre-control device 
emissions of an applicable pollutant are equal to or greater than the 
amount needed for a unit to be classified as a major source. Groups of 
emissions units are not aggregated for this determination, so such 
groups would not be subject to part 64. In addition, fugitive emissions 
are generally not controlled through the use of control devices, so 
there is no need for special applicability or monitoring provisions for 
fugitive emission sources.
    --Emission limitations or standards for which a part 70 permit 
already includes monitoring that is used as a continuous compliance 
determination method. In these instances, there generally is no need to 
require any additional compliance assurance monitoring for that 
emission limitation or standard. There is one exception to using this 
exemption. In some instances a continuous compliance determination 
method may be contingent upon an assumed control device efficiency 
factor. For example, a VOC coating source that includes add-on control 
equipment that destroys VOC emissions may use an assumed control device 
efficiency factor for the control equipment together with coating 
records to calculate compliance with an NSPS requirement. In this 
example, a monthly calculation generally is made using coating records 
and an assumed destruction efficiency factor that is based on the last 
control system performance test. In this example, Sec. 64.2(b)(1)(vi) 
does not allow the exemption from part 64 because the owner or operator 
must assure proper operation and maintenance of the control device for 
the destruction efficiency factor to remain valid. The Agency notes 
that this position is consistent with the NSPS, which generally require 
monitoring of the control equipment in addition to the monthly 
compliance calculation in this type of example. The Agency notes that 
the monitoring under part 64 does not have to be included or otherwise 
affect the existing continuous compliance determination method. In the 
coating example, direct compliance will still be calculated based on 
the approved continuous compliance method. Part 64 monitoring will be 
used to document that the control device continues to operate properly 
and to indicate the need to reestablish the destruction efficiency 
factor through a control device performance test.
    This exemption also raises a question about what constitutes a 
``continuous compliance determination method.'' Section 64.1 defines 
this type of method as a means established in an applicable requirement 
or a part 70 permit for determining compliance on a continuous basis, 
consistent with the averaging period for the applicable requirement. 
The EPA has prepared initial guidance that includes some example of 
this type of monitoring. (See docket item A-91-52-VI-A-8 for a draft of 
this guidance.)
    The Agency notes that if emission limitations or standards other 
than the exempt emission limits described above apply to the same 
pollutant-specific emissions unit, the owner or operator would still be 
subject to part 64 for that pollutant-specific emissions unit and may 
have to upgrade the existing monitoring or add other types of 
monitoring. The Agency believes that for many situations in which both 
exempt and non-exempt emission limits apply to a particular pollutant-
specific emissions unit, the monitoring for the exempt limit may be 
adequate to satisfy part 64 for the other non-exempt emission limit(s). 
Section 64.4(b)(4) of the rule recognizes this possibility and allows 
the owner or operator to meet the obligation to explain the 
appropriateness of its proposed monitoring by stating that it is 
proposing monitoring for non-exempt limits that is based on the 
monitoring conducted for certain types of exempt emission limits.
    Examples of situations that may involve both exempt and non-exempt 
limits for the same pollutant-specific emissions unit include the 
following. One example would be a pollutant-specific emissions unit 
that is subject to both a particulate matter limit and enforceable 
conditions to operate a control device within certain parameters. In 
this example, if compliance with the parameter conditions is determined 
by a continuous compliance determination method, that monitoring could 
be used to provide a reasonable assurance of compliance with the 
particulate matter limit, provided that the monitoring included all 
necessary parameters to satisfy Sec. 64.3(a). In contrast, another 
example of multiple emission limitations or standards could be an 
emissions unit that is subject to a short

[[Page 54917]]

term emission rate limit and an annual throughput limit that has a 
means for determining compliance with total annual throughput. In this 
example, demonstrating compliance with the annual throughput limit is 
unlikely to assure that a control device used to comply with the short 
term limit continues to perform properly, and the owner or operator may 
have to use different or supplemental monitoring to satisfy part 64.
    As noted above, emission limits established under the Acid Rain 
Program are exempt from part 64. The Agency expects that the part 75 
monitoring required for Acid Rain sources likely will generate the data 
necessary to comply with part 64 as applied to other standards 
applicable to the same unit. However, because part 64 requires that 
CEMS data be reported in terms of the applicable emission limit, the 
owner or operator may face some additional requirements in order to 
generate the data in terms of the other non-Acid Rain emission limits 
that apply (such as a lb/mmBtu SO<INF>2</INF> standard).
    --Two exemptions provided for in the 1993 EM proposal have been 
eliminated in part 64. The 1993 EM proposal included exemptions for 
NESHAP standards for asbestos demolition and renovation projects and 
NSPS standards for residential wood heaters. These source categories 
are exempt under part 70 and are not required to obtain operating 
permits. Since part 64 explicitly applies only to sources required to 
obtain a part 70 permit, separate exemptions for these source 
categories are unnecessary in the final rule.
    --In addition to exempting certain emission limitations or 
standards, the 1996 part 64 Draft also introduced an exemption for 
small municipal utility emissions units in response to the large number 
of comments received on this issue during the extended comment period 
on the 1993 EM proposal (over 80 municipal power utilities submitted 
comments on this issue). The exemption applies to small (under 25 
megawatts) existing municipal utility emissions units that are exempt 
from the Acid Rain Program and that supply power for sale only in peak 
demand or emergency situations. As commenters pointed out, these units 
have historically low usage rates, but, because of their nature, owners 
or operators cannot accept enforceable restrictions on the operation of 
these units for any particular year without violating their contractual 
obligations. Thus, these units usually have extremely high potential to 
emit values in comparison to actual emissions. In addition, the Agency 
notes that these units often are owned and operated by small municipal 
authorities and that the actual emissions from these units are minimal 
in many cases. The Agency therefore believes that a limited exemption 
for these units is appropriate.
    To qualify for the exemption, the owners or operators of these 
units must include in their part 70 permit applications documentation 
showing that the unit is exempt from all of the monitoring requirements 
in 40 CFR part 75, and showing that the emissions unit is operated only 
to provide electricity during peaking hours or emergencies. This 
documentation should consist of historical operating data and 
contractual information.
    The owner or operator must also demonstrate that the emissions unit 
has low annual average emissions. The rule requires the owner or 
operator to document that average annual emissions over the last 3 
calendar years of operation are less than 50 percent of the amount 
required to classify the unit as a major source. If less than 3 years 
of historical data are available, the owner or operator can use such 
shorter time period that is available as the appropriate look back 
period.
    The Agency chose the 3-year period to be consistent with the time 
frame used under the Acid Rain Program to define a peaking unit (see 
Sec. 72.2). The 3-year period used under the CAM approach recognizes 
the similar circumstances presented by these small municipal power 
sources. The use of a 50 percent threshold is consistent with EPA's 
January 1995 potential to emit transition policy setting forth EPA 
guidance under which sources that have actual emissions well below 
title V applicability thresholds may avoid title V permitting by 
documenting those low actual emissions (see docket item A-91-52-VI-I-5 
for a copy of this policy). If actual emissions exceed that 50 percent 
value, then the policy requires a source to obtain an enforceable 
restriction to reduce its potential to emit below the title V 
applicability threshold. The Agency believes that the principle behind 
that policy is equally applicable for purposes of this part 64 
exemption. Based on the information supplied in comments submitted by 
the affected municipal utility companies, EPA believes that the vast 
majority of the emissions units under 25 megawatts operated at these 
sources will qualify for this exemption.
    In response to the 1996 part 64 Draft, the Agency again received 
many comments that argued for expansion of the municipal utility 
exemption to other units which have low actual emissions. For example, 
the U.S. Small Business Administration submitted for discussion at the 
September 10, 1996, meeting a proposal (SBA proposal) to exclude 
entirely from part 64 any unit with emissions between 50 percent and 90 
percent of the major source threshold so that the resources that would 
otherwise be spent on implementing part 64 for those sources could be 
saved; further, the SBA comments included a recommendation that EPA 
give partial credit for emission control measures rather than 
determining applicability based on total potential pre-control device 
emissions. The SBA proposal stated that this would eliminate possibly 
thousands of sources that do not need to be covered by part 64 since 
the reasonable assurance can be obtained through the facilities' own 
records. A number of commenters specifically expressed their support 
for the SBA proposal and others stated generally that they were in 
favor of such an exemption, arguing that any unit that can demonstrate 
a history of limited usage and an expectation of continued limited 
usage should be exempted.
    The EPA disagrees with the concept of using actual emissions as the 
overall basis for part 64 applicability or as the basis for expanding 
significantly the municipal utility exemption. First, actual emissions 
can vary with changes in production. More importantly, for units with 
control devices, calculations of actual emissions necessarily rely on 
assumptions about on-going performance that part 64 is intended to 
verify. Further, to assure that units remain under the major source 
threshold is not the goal of part 64, but, instead, the goal of part 64 
is to assure that sources meet all applicable requirements. Finally, 
because the types of sources to which commenters referred are unlikely 
to meet the control device applicability criterion of the final rule, 
the Agency feels even more strongly that the final rule will not 
subject small units to inappropriate monitoring. The Agency notes, 
however, that such units will remain subject to the monitoring 
requirements in part 70, and may have to adopt new or modified 
monitoring to comply with those requirements, even though part 64 does 
not apply.
4. Hazardous Air Pollutant Requirements
    Under the 1993 EM proposal, part 64 would have applied to all 
emission limitations or standards established under 40 CFR part 61 at 
any source that is required to obtain an operating permit under part 
70. The proposed rule contained an exemption, retained in

[[Page 54918]]

modified form in the final part 64 rule, for all hazardous air 
pollutant emissions standards promulgated pursuant to section 112 of 
the Clean Air Act except for those standards established in part 61 
prior to the 1990 Amendments to the Act.
    After receiving substantial public comment on the applicability of 
part 64 to hazardous air pollutants, the Agency has significantly 
modified its approach to HAPs under part 64. Hazardous air pollutant 
sources are no longer a separate category subject to a different 
applicability test. Instead, hazardous air pollutant emissions 
limitations and standards are treated the same as those for criteria 
air pollutants. Thus, a hazardous air pollutant-specific emissions unit 
is subject to part 64 only if it meets the applicability criteria set 
forth in Sec. 64.2(a).
    This approach is consistent with the Agency's overall goal of 
streamlining part 64. The EPA believes the final part 64, in 
conjunction with other regulatory provisions, provides for sufficient 
monitoring of hazardous air pollutant sources to both satisfy the 
statutory enhanced monitoring mandate and to meet the special concerns 
associated with regulating pollutants of this type. In addition, units 
and sources which do not meet the part 64 applicability threshold will 
still be subject to part 61 compliance monitoring and, if applicable, 
part 70 monitoring. For those units, EPA considers such monitoring 
sufficient to address the special concerns of regulating hazardous air 
pollutants.
    With respect to emissions units subject to new hazardous air 
pollutant standards under amended section 112 of the Act, EPA will 
include appropriate monitoring requirements as part of those new 
hazardous air pollutant standards. Since part 64 monitoring for these 
standards would be needlessly duplicative, such standards are covered 
by the exemption in Sec. 64.2(b)(1)(i). This approach is consistent 
with EPA's statement in the July 21, 1992 preamble to 40 CFR part 70 
that all future rulemakings will have no gap in their monitoring 
provisions (see 57 FR 32278).

C. Section 64.3--Monitoring Design Criteria

    Section 64.3 contains the design criteria for satisfying part 64. 
The selection and design of monitoring have undergone revision in the 
final rule. Some of these revisions were necessary to conform these 
provisions to applicability and implementation requirements under the 
final rule. Others have been made in response to public comments on the 
monitoring design and selection requirements in the 1993 proposed EM 
rule and subsequent drafts of part 64. These revisions reflect both the 
objective of providing a reasonable assurance of compliance with 
applicable requirements at lower cost than the 1993 proposed EM rule 
and the Agency's goal of developing a more simplified structure for 
part 64. The following section describes the specific revisions to 
these provisions and the Agency's rationale for making these changes.
1. General Criteria
    a. Overview. The general purpose of the monitoring required by part 
64 is to assure compliance with emission standards through requiring 
monitoring of the operation and maintenance of the control equipment 
and, if applicable, operating conditions of the pollutant-specific 
emissions unit. A basic assumption of EPA air pollution control 
rulemaking, at least under technology-based programs such as the NSPS 
program, is that an emission limit should be established at a point 
where a well operated and maintained source can achieve the limit under 
all expected operating conditions using control equipment that has been 
shown through a performance test to be capable of achieving the 
emission limit. This demonstration through a performance test is 
conducted under conditions specified by the applicable rule or, if not 
specified, generally under conditions representative of maximum 
emission potential under anticipated operating conditions (generally, 
but not always, at full load). Logically, therefore, once an owner or 
operator has shown that the installed control equipment can comply with 
an emission limit, there will be a reasonable assurance of ongoing 
compliance with the emission limit as long as the emissions unit is 
operated under the conditions anticipated and the control equipment is 
operated and maintained properly. This logical assumption is the basis 
of EPA standard-setting under the NSPS program and serves as the model 
for the CAM approach as well.
    For example, under 40 CFR part 60, subpart NN, Phosphate Rock 
Plants, the standard for particulate matter is determined through 
Method 5 testing. The final preamble noted that certain commenters 
believed that the particulate emission limits ``were too stringent to 
be achieved on a continuous basis.'' Upon review of the information, 
EPA revised the standard because its evaluation ``indicated that the 
proposed emission limits . . . could not be achieved continuously under 
all operating conditions which are likely to occur.'' 47 FR 16584 
(April 16, 1982). EPA then stated that ``(a)s required by the Clean Air 
Act, the promulgated . . . emission limits are based on the performance 
of the best available control equipment on the worst case uncontrolled 
emission levels. The best control systems have been demonstrated to be 
continuously effective. Therefore, there should be no problems 
achieving the standards if the control equipment is properly maintained 
and operated.'' Id. at 16585. This example documents the close nexus of 
first demonstrating through a performance test that the installed 
control equipment is capable of achieving the standard on a continuous 
basis and then properly operating and maintaining that equipment so as 
to provide a reasonable assurance of continuous compliance with the 
standard.
    In EPA's Response to Remand in Portland Cement Association v. 
Ruckelshaus (see docket item A-91-52-VI-I-11), EPA further emphasized, 
in its discussion on opacity, the important relationship between proper 
operation and maintenance and attainment of the standards. The Agency 
stated, ``[T]he opacity standards and maintenance requirements were 
both promulgated, and work in tandem to guarantee that proper 
maintenance and operation of pollution control equipment, the sine qua 
non of continuous compliance with emission limits, can in fact be 
required and monitored.'' (Response to Remand, p. 87.) EPA discussed 
the fact that opacity standards provide enforcement agencies with a 
convenient indicator of whether pollution control devices are being 
properly operated and maintained, and therefore whether the standards 
are being met. (Response to Remand, p. 27-28.)
    These examples point to the underlying assumption that there is a 
reasonable assurance of compliance with emission limits so long as the 
emission unit is operated under the conditions anticipated and the 
control equipment that has been proven capable of complying continues 
to be operated and maintained properly. In most cases, this 
relationship can be shown to exist through the performance testing 
without additional site-specific correlation of operational indicators 
with actual emission values. The monitoring design criteria in 
Sec. 64.3(a) build on this fundamental premise of the regulatory 
structure.
    Thus, Sec. 64.3(a) states that units with control devices must meet 
certain general monitoring design criteria in order to provide a 
reasonable assurance

[[Page 54919]]

of compliance with emission limitations or standards for the 
anticipated range of operations at a pollutant-specific emissions unit. 
These criteria mandate the monitoring of one or more indicators of the 
performance of the applicable control device, associated capture 
system, and/or any processes significant to achieving compliance. The 
owner or operator shall establish appropriate ranges or designated 
conditions for the selected indicators such that operating within the 
established ranges will provide a reasonable assurance of compliance 
for the anticipated range of operating conditions. The requirement to 
establish an indicator range provides the objective screening measure 
to indicate proper operation and maintenance of the emissions unit and 
the control technology, i.e., operation and maintenance such that there 
is a reasonable assurance of compliance with emission limitations or 
standards. Monitoring based on indicator ranges that establish expected 
operating conditions and the proper functioning of control technology 
should take into account reasonably anticipated operating conditions 
and the process and pollution control device parameters that 
significantly affect emission control performance. The Agency notes 
that monitoring which fails to take into account significant process or 
control device parameters is unlikely to provide the reasonable 
assurance of compliance with emissions limitations or standards. The 
Agency does not expect that such parameters would normally include 
records of regular maintenance practices (e.g., periodic inspection and 
replacement of parts); these records may or may not be addressed in 
separate permit conditions relative to part 70 requirements. The Agency 
also emphasizes that a failure to stay within the indicator range does 
not automatically indicate a failure to satisfy applicable 
requirements. The failure to stay within an indicator range (over the 
appropriate averaging period, as discussed below) does indicate the 
need for the owner or operator to evaluate and determine whether 
corrective action is necessary to return operations within design 
parameters, and to act upon that determination as appropriate.
    The use of operational data collected during performance testing is 
a key element in establishing indicator ranges; however, other relevant 
information in establishing indicator ranges would be engineering 
assessments, historical data, and vendor data. Indicator ranges do not 
need to be correlated across the whole range of potential emissions. 
Criteria developed in the design of the control equipment for the 
emissions unit may be used in establishing operating indicator ranges. 
For example, the engineering specifications for a venturi scrubber 
installed to control particulate emissions from an affected unit may 
include design operational ranges for liquid flow rate and pressure 
drop across the venturi. Assume for this simplified example that the 
scrubber design conditions are intended to achieve the desired emission 
reduction for uncontrolled pollutant rates that correspond to 120 
percent of the affected unit's process design rate. The results of a 
performance test during which the scrubber is operated within these 
design conditions and the process is operated at conditions 
representative of high load (near 100 percent of process design rate) 
would be used to confirm that operating within the design conditions, 
the design ranges for the liquid flow rate in conjunction with the 
pressure drop across the venturi, achieves the emission reduction 
desired and provides a reasonable assurance of compliance across the 
anticipated range of process conditions for ongoing operation.
    Review of historical monitoring data may also be used in defining 
an indicator range that provides a reasonable assurance of compliance 
with emission limits. Consider the example of a process dryer equipped 
with a low-energy wet scrubber for particulate matter control. The 
scrubber exhaust gas temperature is indicative of adequate water flow 
(as a result of the heat exchange between the dryer effluent stream and 
the scrubber water). However, since the inlet scrubber water 
temperature is affected by ambient temperature, the resulting scrubber 
outlet temperature will be affected by ambient conditions. Since the 
scrubber outlet temperature will vary somewhat as a result of ambient 
temperature, it makes sense to consider historical data from different 
seasons of the year when establishing the indicator range (maximum 
allowable exhaust temperature). In other words, if the performance test 
were conducted in the spring, one should also consider the historical 
data from the summer months (when the exhaust temperature would be 
expected to be slightly higher) when establishing the indicator range.
    b. Possible Monitoring Methods. Section 64.4(a)(2) of the 1993 
proposed EM rule stated that an enhanced monitoring protocol could 
include existing, modified, or new monitoring systems. It also 
contained a list of possible monitoring methods which could satisfy the 
rule. The basic elements of this subsection have been moved in the 
final rule to the definition of ``monitoring'' in Sec. 64.1. The Agency 
has made several technical changes to the list of monitoring 
methodologies in response to comments received. See Section II.A. and 
the Response to Comments Document for further discussion.
    c. Indicator Ranges or Designated Conditions. Sections 64.3(a)(2) 
and (3) of the final rule require the owner or operator of an affected 
pollutant-specific emissions unit to establish ranges or designated 
conditions of the indicators to be monitored. These ranges (e.g., 
minimum to maximum parameter value) or conditions (e.g., specific fuel 
or raw material type or control device adjustment) must be established 
at a level where the monitoring can assess whether there is a 
reasonable assurance of compliance with applicable requirements.
    The addition of indicator range requirements to the general 
monitoring design criteria serves the objectives of part 64 and 
provides the permitting authority and the owner or operator of an 
affected source with information about the operation and maintenance of 
control measures in order to address any problems with that operation 
and maintenance before an emissions unit fails to comply with 
applicable requirements. An excursion from an indicator range or 
designated condition indicates a potential problem in the operation and 
maintenance of the control device and a possible exception to 
compliance with applicable requirements. The excursion signals, at a 
minimum, that the owner or operator should take appropriate corrective 
action to return operations within the established ranges. However, an 
excursion from an indicator range does not necessarily constitute a 
failure to comply with the underlying emissions limitation or standard. 
See Section II.D. below for further discussion on the degree of 
documentation required to establish indicator ranges under the final 
rule.
    Sections 64.3(a)(3)(i)-(iv) state that ranges may be set as 
follows: established as a single maximum or minimum value if 
appropriate or at different levels that vary depending on alternative 
operating conditions; expressed as a function of process variables; 
expressed as maintaining the applicable parameter in a particular 
operational status; or expressed as interdependent between more than 
one indicator. These sections also provide examples of how such 
different forms of ranges might be employed. The description of what 
type of indicators and indicator ranges may

[[Page 54920]]

be employed under part 64 is designed to have a great deal of 
flexibility. This allows owners or operators to develop indicators and 
ranges that are most appropriate for their affected emissions units, so 
long as the basic design criteria of part 64 are met. The Agency is 
also developing guidance materials that will provide more specific 
examples of the various forms indicator ranges may take.
     d. Control Device Bypass. Another monitor design requirement in 
the final rule addresses the possibility of control device bypass. 
Section 64.3(a)(2) requires that the monitoring be designed to detect 
any bypass of a control device or capture system, if such bypass can 
occur based on the design of the pollutant-specific emissions unit. The 
Agency believes this requirement is necessary under the CAM approach. 
Only pollutant-specific emissions units which use control devices to 
achieve regulatory compliance are subject to part 64. Part 64 
monitoring generally will consist of monitoring parameters critical to 
the operation of those control devices. The monitoring will not be able 
to provide a reasonable assurance of compliance with applicable 
requirements if air pollutant emissions are potentially circumventing 
the control devices and/or capture systems being monitored. The Agency 
has therefore added this requirement to ensure that no emissions are 
bypassing the control device or capture system.
    The Agency notes that certain comments on the 1996 part 64 Draft 
objected to this requirement. One objection was that it could be read 
to require monitoring of ``bypass'' that involves routine recycling of 
vent streams to a process where the control device is used as a backup 
in case such process recycling cannot occur. The final rule adds the 
phrase ``to the atmosphere'' to clarify that only bypasses which result 
in discharge to the atmosphere require monitoring. Another concern was 
that whether bypass monitoring should be required is often negotiated 
as part of underlying rulemakings and this requirement could undo 
agreements reached on those underlying rules. The Agency has added a 
provision to clarify that bypass monitoring is not required if an 
underlying rule specifically provides that it is not required for 
certain operations or units. Finally, a concern was raised that certain 
underlying rules provide for design features that obviate the need for 
monitoring (such as the use of locking car seals). The final rule 
requires bypass monitoring only if the bypass can occur based on the 
unit's design. Where features such as locking car seals are used, the 
design of the unit effectively prevents bypass and thus monitoring 
would not be required.
    e. Process and Capture System Monitoring. Commenters on the 1996 
part 64 Draft also objected to the requirement that the monitoring 
include process monitoring if necessary to assure proper operation and 
maintenance of the control device. The final rule retains this 
requirement, but the language has been rephrased to clarify that 
process monitoring must be conducted only as necessary to document that 
the control equipment is being operated properly. The simplest example 
would be throughput monitoring to assure that the design capacity of 
the control equipment is not exceeded. The Agency believes that this 
type of monitoring is essential to assuring that the control equipment 
is used in accordance with its design and in a manner that will provide 
a reasonable assurance of compliance.
    Similarly, some commenters objected to the monitoring of capture 
systems. The Agency believes that this monitoring is essential for the 
same reasons as bypass and process monitoring may be critical to 
assuring proper operation and maintenance of control equipment and 
providing a reasonable assurance of compliance with emission limits. If 
emissions are not properly captured, those emissions will be released 
uncontrolled. That result likely would constitute a significant 
compliance problem even if the control equipment itself was being 
operated and maintained properly. It is essential that the emissions 
which a control device is supposed to be controlling are in fact sent 
to the device for control. Thus the Agency believes that assuring that 
the capture system is properly operated and maintained is also 
essential.
    f. Fugitive Emissions Monitoring. Under the 1993 EM proposal, 
fugitive emission points for which compliance is evaluated on a 
process-wide or facility-wide basis were potentially subject to part 64 
enhanced monitoring requirements. Section 64.4(d) of the proposed rule 
would have established enhanced monitoring protocol requirements for 
such fugitive emissions points. Many commenters raised objections to 
these provisions, arguing that Sec. 64.4(d) required either burdensome 
monitoring of emissions from each fugitive emissions point or the use 
of costly monitoring devices to monitor fugitive emissions. The Agency 
does not necessarily agree with these comments, noting that proposed 
Sec. 64.4(d) was intended to allow for cost-effective multi-point 
monitoring at affected fugitive emissions sources. The final rule, 
however, applies only to those emissions units for which emissions are 
vented to a control device. By definition, fugitive emissions are those 
emissions which cannot reasonably be vented through a stack, chimney, 
vent, or similar opening and thus will not be subject to part 64. Since 
there is no need for detailed fugitive emissions monitoring 
requirements under the final rule, the provisions in proposed 
Sec. 64.4(d) have been eliminated.
2. Performance and Operating Criteria
    The final part 64, like the 1993 EM proposal, requires that part 64 
monitoring be subject to minimum performance specifications, quality 
assurance and control requirements, monitoring frequency requirements, 
and data availability requirements. These requirements assure that the 
data generated by the monitoring under part 64 present valid and 
sufficient information on the actual conditions being monitored. The 
final rule includes a series of performance and operating design 
criteria in Secs. 64.3(b) through (d). The Agency received substantial 
public comment on the performance and operating criteria of the 1993 EM 
proposal, which were contained in a series of four appendices. Many 
commenters raised concerns that the organization of the appendices was 
confusing. A number of commenters suggested that the appendices 
required certain monitoring options to achieve inapplicable 
specifications or did not provide adequate guidance on the requirements 
for non-instrumental monitoring options. Commenters also raised a 
number of concerns specific to individual requirements. Finally, a 
great many commenters argued that the reliance on detailed 
specifications in the appendices which focused on the use of certain 
monitoring methodologies, such as CEMS, precluded the use of more cost-
effective alternative methodologies, creating a strong bias for the use 
of continuous emission monitoring methodologies.
    The Agency agrees with a number of those comments and has 
substantially revised the performance and operating criteria in the 
final rule to address the concerns they raised. Overall, these 
requirements have been greatly streamlined and simplified. There are no 
appendices to the final rule delineating more detailed performance and 
operating criteria. To assure consistency with existing monitoring 
programs, the performance criteria in the final rule also reflect other 
federal monitoring requirements, such as the NSPS general provisions in 
40 CFR part

[[Page 54921]]

60 and the NESHAP general provisions in 40 CFR part 63. The following 
discussion addresses each of the key performance and operating criteria 
in the final rule.
    a. Data Representativeness. Section 64.3(b)(1) of the final rule 
requires that the monitoring proposed by the owner or operator include 
location and installation specifications (if applicable) that allow for 
the obtaining of data which are representative of the emissions or 
parameters being monitored. Although this provision describes no 
specific tests for monitoring plan acceptability, it does establish an 
objective duty to insure that the data collected are representative of 
the operations being monitored. This provision is similar to the 
analogous requirements included in appendix B of the 1993 EM proposal. 
It is also analogous to the general monitoring provisions applicable to 
all monitoring under the NSPS program in Sec. 60.13. The Agency has 
added the phrase ``if applicable'' to clarify that noninstrumental 
monitoring approaches may not require location or installation 
specifications.
    The 1993 EM proposal would have required owners or operators to 
``[s]atisfy applicable performance, equipment, installation and 
calibration gas specifications in accordance with the specifications 
and procedures provided in appendices A and B of this part.'' The 
appendices then required all enhanced monitoring protocols to satisfy 
generally applicable performance specifications including relative 
accuracy requirements; maximum levels of calibration error; measurement 
span requirements; response time requirements; measurement technique 
procedures; and requirements for equipment design, installation, and 
location. Many commenters observed that the high level of specificity 
required in the proposed appendices would limit the types of monitoring 
protocols that could be approved, while many other commenters argued 
that the performance and operating requirements were too subjective 
when applied in the context of demonstrating compliance with the 1993 
EM proposed rule's general monitoring requirements. The Agency believes 
that such detailed requirements are unnecessary for the type of 
monitoring that is required to satisfy the final rule, but does believe 
that the general obligation to assure that representative data are 
obtained is necessary in part 64 just as it is in other programs such 
as NSPS.
    b. Verification of Operational Status. Section 64.3(b)(2) requires 
verification procedures to confirm the initial operational status of 
new or modified monitoring equipment. These requirements specify that 
the owner or operator must consider manufacturer requirements or 
recommendations for installation, calibration and start-up operation. 
Owners or operators must provide documentation where the manufacturer's 
procedures are not followed. The Agency notes that under the NSPS 
program such manufacturer requirements and recommendations must be 
followed. However, because of the breadth of part 64 applicability, the 
Agency believes that the more flexible language in Sec. 64.3(b)(2) is 
appropriate, especially given that the submittal requirements in 
Sec. 64.4 will require that the owner or operator document the changes 
it proposes.
    Some comments on the 1996 part 64 Draft stated that the 
requirements to verify operational status were overly burdensome given 
that many units will rely on existing monitoring to satisfy part 64. 
The final rule clarifies that verification of operational status is 
required only for units with new or modified monitoring.
    c. Quality Assurance and Control. Section 64.3(b)(3) of the final 
rule requires quality assurance and control practices which are 
``adequate to ensure the continuing validity of the data.'' This 
language ensures that monitoring under part 64 will have to include 
adequate procedures to document that the monitoring remains operational 
and can provide suitable readings for the purpose of measuring changes 
in control performance. Satisfying this general design criterion should 
not be confused with the detailed quality assurance provisions required 
for monitors that are used to determine direct emission limit 
compliance, such as appendix F to part 60. The 1993 EM proposal 
generally would have required compliance with appendix F for CEMS or 
comparable quality assurance requirements for other monitoring 
approaches. Numerous commenters expressed concerns about the burdens of 
quality assurance under the proposed EM rule. They pointed out several 
instances in the proposed appendices that appeared to establish 
presumptions of daily calibrations for all types of enhanced monitoring 
protocols or appeared to require overly frequent reverification of 
parametric correlations.
    In contrast, the focus of the final rule's quality assurance 
requirements is on the minimum degree of ongoing quality checks that 
are necessary to rely on the data for purposes of indicating whether 
the unit remains in compliance and whether corrective action is 
necessary. The Agency recognizes that many types of monitoring which 
satisfy the final rule will not be based on the type of sophisticated 
equipment that is prone to calibration drift and loss of data quality 
over time, and the revised quality assurance provisions of the final 
rule reflect this understanding. The required level of quality 
assurance differs from certain existing quality assurance procedures 
such as appendix F of 40 CFR part 60 for a CEMS. With respect to a 
CEMS, the general requirements for assuring ongoing data quality that 
are contained in 40 CFR 60.13 and the performance specifications in 
appendix B of part 60 (such as zero and span checks) provide adequate 
quality control checks for the purpose of using the CEMS to indicate 
control performance for providing assurance of compliance. This 
approach of requiring only limited quality assurance is followed under 
the NSPS where a CEMS is not used as the compliance test method for 
direct continuous compliance monitoring. For types of monitoring other 
than CEMS, ongoing quality control measures must be adequate to ensure 
that the monitoring remains operational and can provide readings 
suitable for the purpose of measuring changes in control performance 
that indicate possible exceptions to compliance. An example of this 
type of requirement is the quarterly recalibration requirement in 
Sec. 60.683(c) for wet scrubber parameter monitoring at wool fiberglass 
insulation manufacturing plants.
    Again, the final Sec. 64.3(b) directs owners or operators to 
consider manufacturer requirements or recommendations in developing 
quality assurance practices, and Sec. 64.4 requires the owner or 
operator to document any changes in recommended quality assurance 
practices. The permitting authority and others can then evaluate the 
proposed procedures during the permitting process.
    d. Frequency of Monitoring. Section 64.3(b)(4) of the final rule 
establishes the general criteria for monitoring frequency, data 
collection procedures (such as manual log entry, strip chart, or 
computerized collection procedures), and data averaging periods, if 
applicable to the proposed monitoring. The final rule requires that the 
monitoring frequency (including associated averaging periods) be 
designed to obtain data at such intervals that are, at a minimum, 
commensurate with the time period over which an excursion from an 
indicator range is likely to be observed based on the characteristics 
and typical variability of the pollutant-specific emissions unit 
(including the control device and associated capture system).

[[Page 54922]]

In addition, the final rule specifies minimum data collection frequency 
for pollutant-specific emissions units in accordance with their 
potential to emit. For ``large'' pollutant-specific emissions units 
(i.e., those units with the potential to emit the applicable pollutant 
emitted in an amount equivalent to or in excess of the amount 
established for classification as a major source), the monitoring 
frequency generally must satisfy a design criterion of four or more 
data values equally spaced over each hour of operation. This minimum 
data collection frequency is consistent with the frequency established 
by the Agency for continuous monitoring systems. Note that a permitting 
authority may reduce this minimum data collection frequency upon 
submission and approval of a request prepared by the owner or operator, 
and the rule provides a non-exclusive list of situations in which less 
frequent monitoring of certain parameters may be warranted. Other 
pollutant-specific emissions units are subject to a less frequent data 
collection requirement but some data must be collected for every unit 
subject to this rule at least once per day. The final rule thus sets a 
monitoring frequency standard appropriate to the focus on detecting 
changes in control device performance which could indicate possible 
noncompliance and for which corrective action is appropriate.
    For example, many types of control devices are subject to rapid 
changes in performance and thus the frequency design criterion could 
result in frequent, near continuous collection of parametric data that 
are subsequently averaged over an appropriate period of time. Many NSPS 
subparts require continuous parametric control device data, which are 
then averaged over an appropriate interval (often consistent with the 
required minimum time for conducting a compliance test). Recent NESHAP 
have required control device parameter monitoring for direct compliance 
purposes. In these instances, a daily average of continuous data (i.e., 
data recorded at least every 15 minutes) is often used (see, e.g., 
Sec. 63.152(b)(2)). For some control devices, the intervals between 
data collection points may be increased. The Agency is in the process 
of developing guidance for part 64 implementation, including example 
monitoring approaches. The guidance will indicate how the frequency of 
monitoring, data collection procedures, and averaging of data points 
can vary based on the type of emissions unit and the control device 
involved.
    e. Data Availability. The 1996 part 64 Draft rule included a 
presumptive minimum data availability of 90 percent for the averaging 
periods in a reporting period. The final rule does not include such a 
presumptive requirement opting instead for affording the source owner 
or operator and the permitting authority flexibility in establishing 
appropriate site-specific conditions. Further, the final rule maintains 
the general duty requirement in Sec. 64.7 that the owner or operator 
shall maintain and operate the monitoring at all times the pollutant-
specific emissions unit is operating except for periods of monitoring 
malfunctions, associated repairs, and required quality assurance or 
control activities (such as calibration checks and (if applicable) 
required zero and span adjustments). This section of the final rule 
also requires that the owner or operator shall use all the data 
collected during all other periods in assessing the operation of the 
control device and associated control system. Under the savings 
provisions of Sec. 64.10 of the final rule, source owners or operators 
must satisfy any existing data availability requirement established for 
monitoring associated with a particular emission limitation or 
standard.
    The 1993 EM proposal would have required that an enhanced 
monitoring protocol satisfy any minimum data availability requirement 
that is applicable to the monitoring under a separate applicable 
emission limitation or standard pursuant to part 60 or 61 of this 
chapter. Where no existing data availability requirement would have 
applied, the proposed rule would have required the enhanced monitoring 
protocol to satisfy a data availability requirement that reflected 
obtaining quality-assured data for all emissions unit operating time 
periods excluding a fixed percentage of operating time that the owner 
or operator justified to the permitting authority as necessary to 
conduct quality assurance procedures. The preamble to the proposed rule 
stated that the only acceptable downtime under this requirement would 
be the time necessary to perform quality assurance testing and routine 
maintenance. The primary concern expressed in public comments on the 
data availability requirement was that the default requirement failed 
to take into account the likelihood that some repairs of instrumental 
components would be necessary even if the owner or operator performed 
all routine maintenance as appropriate. The Agency believes that the 
general duty requirement in the final rule effectively addresses the 
commenters' concerns, while still assuring that the owner or operator 
is responsible for collecting data at all required intervals, except 
where downtime is necessary to conduct required quality assurance or to 
respond to malfunctions that could not reasonably have been prevented.
    A number of comments on the 1996 part 64 Draft objected to the 90 
percent data availability presumption. Many pointed to a number of 
applicable requirements in which EPA has used 75 percent as the 
required minimum data availability. Others argued that EPA failed to 
present any data to document the reasonableness of the presumption. The 
Agency agrees with some of the commenters that a presumptive minimum 
data availability requirement may not be not generally applicable; 
although, the general obligations to operate the monitoring at all 
times with only specific exception periods and to collect and use all 
the data for reporting purposes are universal. The final rule reflects 
this position and allows the source owner or operator and the 
permitting authority the flexibility to specify a separate minimum data 
availability if justified or required under a separate rule.
3. Special Considerations for CEMS, COMS and PEMS
    One method of assessing control performance is to calculate 
emission (or opacity) rates directly in order to track trends in 
emissions (or opacity) that document decreased control effectiveness. 
This type of monitoring could include a continuous emission or opacity 
monitoring system (CEMS or COMS) or a predictive emission monitoring 
system (PEMS) in which various process and control parameters are 
evaluated to predict emissions. (Where this type of monitoring is 
specified by the applicable standard to be used to determine compliance 
with an emission standard or limitation on a continuous basis, the 
requirements of part 64 do not apply to that emission standard or 
limitation. See Sec. 64.2(b)(1)(vi).)
    The EPA believes that these types of monitoring are preferable from 
a technical and policy perspective as a means of assuring compliance 
with applicable requirements because they can provide data directly in 
terms of the applicable emission limitation or standard. Therefore, 
where such systems are already required, Sec. 64.3(d)(1) mandates that 
the design of the monitoring under part 64 incorporate such systems. 
This means that source owners and or operators whose emission units 
have had CEMS, COMS, and/or PEMS imposed by underlying regulations, 
emissions trading programs, judicial settlements,

[[Page 54923]]

or through other circumstances must use those CEMS, COMS, and/or PEMS 
when complying with part 64 for those emissions units. Even where the 
use of such monitoring is not mandated, the use of any of these types 
of systems in accordance with general monitoring requirements and 
performance specifications (or comparable permitting authority 
requirements if there are no requirements specified for a particular 
system) will be sufficient for a CEMS, COMS or PEMS to satisfy 
generally the design criteria in Sec. 64.3(a) and (b).
    One exception to this general rule is that if a COMS is used as a 
control performance indicator, and both a particulate matter and 
opacity standard apply, the monitoring will have to include an 
indicator range satisfying Sec. 64.3(a)(2) and (3). Comments received 
in response to the 1996 part 64 Draft included the suggestion that COMS 
not be subject to the requirement to establish indicator ranges. The 
Agency has decided to retain this requirement. A CEMS or PEMS will 
provide data in terms of the applicable pollutant and therefore the 
process of identifying and reporting exceedances serves the same 
purpose as an indicator range. For assuring compliance with an opacity 
standard, a COMS also achieves this objective. However, depending on 
the type of control equipment being used and the design of an emissions 
unit (especially stack diameter), opacity standards are often 
established at a level which represents a likely significant exceedance 
of the particulate matter standard. In those circumstances, an opacity 
level below a required opacity standard would be more appropriate as a 
CAM indicator. Therefore, the use of a COMS may require an appropriate 
indicator range to be established that is different than the applicable 
opacity standard. The Agency notes that the averaging period for such 
an indicator range would not necessarily have to be consistent with the 
typical averaging time of an opacity standard (i.e., six minutes).
    The final special design criterion for a CEMS, COMS or PEMS is to 
design the system to allow for reporting of exceedances. Again, in many 
cases, the reporting requirements for exceedances (or excess emissions) 
will already be established in existing requirements. However, in some 
cases the owner or operator, prior to implementing part 64, will not 
have continuous monitoring associated with an applicable emission 
limit, and the underlying regulation may not specify an appropriate 
time period for averaging data to report excess emissions. For example, 
this situation could arise in the example provided above for a part 75 
Acid Rain CEMS being used to monitor compliance with a SIP limit. In 
this circumstance, the owner or operator will have to design the system 
to include an appropriate period for defining exceedances consistent 
with the emission limitation or standard. If the underlying applicable 
requirement does not require use of a specific averaging period, the 
averaging period should be designed using the same criteria as used for 
other part 64 monitoring under Sec. 64.3(b)(4).
    There was a concern about a perceived bias towards continuous 
emission monitoring methodologies in many public comments on the 
monitoring design and selection provisions of the 1993 EM proposal. In 
addition, many comments supported the notion that existing monitoring 
should be used wherever possible to reduce the burdens of part 64. 
Section 64.3(d) addresses both of these comment areas. It emphasizes 
the use of existing monitoring where that monitoring on its face is 
able to meet the part 64 design criteria, but it clarifies that the 
rule does not mandate the use of CEMS in situations where such 
monitoring is not already required. See also Section II.D. below which 
discusses in further detail the potential use of existing monitoring to 
satisfy part 64.
    Stakeholders commented that the 1996 part 64 Draft rule did not 
address procedures for approving alternatives to CEMS or COMS as per 
the procedures specified in the general provisions of 40 CFR parts 60, 
61, and 63. The Agency already has procedures for documenting, 
reviewing, and approving alternatives to performance test methods and 
monitoring procedures. Part 64 need not address these procedures. The 
Agency recommends that source owners or operators wishing to pursue 
alternatives to CEMS or COMS follow existing alternative methods 
processes.
4. Monitor Failures
    Section 64.4(g) of the 1993 EM proposal would have provided a 
defense to violations of the data availability requirement where an 
interruption of the normal operation of an enhanced monitoring protocol 
was the result of a monitor failure or malfunction. This section would 
have operated in conjunction with proposed Sec. 64.5(e) to establish 
general notification and corrective action requirements in response to 
monitor failures and malfunctions. The proposed rule would have 
provided a defense to data availability violations where the following 
criteria were met: The monitoring failure was the result of a sudden 
and unforeseeable malfunction; the monitoring systems and procedures 
had been properly operated and maintained prior to and up to the time 
of the malfunction; and the owner or operator took all reasonable steps 
to minimize the period the monitoring system was inoperative.
    This section has been eliminated in the final rule. The Agency does 
not believe that there is a need for a data availability violation 
defense in part 64. The final rule does not require that the permit 
establish a specific data availability requirement. Rather, the owner 
or operator is under a general duty to operate the monitoring at all 
required intervals whenever the emissions unit is operating. The only 
exception to this duty is if the inoperation of the monitoring is 
caused by a monitor malfunction, associated repairs or required quality 
assurance or control activities. Monitor malfunctions are limited to 
those breakdowns which occur as a result of a sudden, infrequent, and 
not reasonably preventable failure of the monitoring to provide valid 
data. Monitoring failures that are caused in part by poor maintenance 
or careless operation are not considered malfunctions. This approach is 
similar to the malfunction defense included in the proposed rule, but 
does not entail the elaborate procedural elements of the proposed rule. 
To the extent a particular data availability requirement cannot be 
achieved for reasons that are no fault of the owner or operator, EPA 
believes that the proper use of oversight discretion can account for 
those situations.

D. Section 64.4--Submittal Requirements

    Section 64.4 of the final rule outlines what information the owner 
or operator must submit with a part 70 permit application to propose 
the monitoring approach selected by the owner or operator. The required 
information has two basic components: general information necessary to 
justify the appropriateness of the proposed monitoring; and information 
to justify the appropriateness of the indicator ranges to be used for 
reporting exceedances or excursions.
1. General Information on the Proposed Monitoring
    Section 64.4(a) first requires that the owner or operator identify 
the basic monitoring approach and indicator ranges that will form the 
primary elements of the monitoring, as well as the key performance and 
operating specifications needed to meet the design criteria in 
Sec. 64.3. In submitting proposed indicator ranges, the owner or

[[Page 54924]]

operator can either submit the actual proposed ranges or the 
methodology that will be followed to establish the indicator ranges.
    Section 64.4(b) then requires that the owner or operator submit 
relevant information to justify the proposed monitoring approach. The 
justification can rely on any available information, including 
appropriate reference materials and guidance documents. If an existing 
requirement already establishes monitoring for the pollutant-specific 
emissions unit, the justification can rely in part on that existing 
requirement. For certain types of monitoring, no extensive 
justification should be necessary because the final rule creates a 
rebuttable presumption that the monitoring satisfies part 64. When an 
owner or operator relies on one of these monitoring approaches, all 
that initially should be necessary is an explanation of why the 
monitoring is applicable to the unit in question. These types of 
monitoring include CEMS, COMS, or PEMS; excepted or alternative 
monitoring approaches allowed under part 75; and continuous compliance 
determination monitoring or monitoring for post-11/90 NSPS and NESHAP 
requirements that are exempt under Sec. 64.2(b) but that may be 
applicable to the control equipment for other non-exempt emissions 
limitations at the same emissions unit. The reason for this presumption 
is similar to the reason for excepting from part 64 units that have 
such monitoring as their compliance determination method. The rule also 
notes that presumptively acceptable or required monitoring approaches 
established by rule by a State to achieve compliance with part 64 are 
deemed presumptively acceptable. This last option is included to 
promote the adoption of State programmatic rules designed to detail 
presumptively appropriate part 64 monitoring.
    Finally, consistent with Panhandle Producers & Royalty Owners Ass'n 
v. Economic Regulatory Administration, 822 F.2d 1105 (D.C. Cir. 1987), 
the rule includes as presumptively acceptable monitoring, monitoring 
that is so designated by EPA through guidance documents. Such 
presumptively acceptable monitoring identified by EPA in guidance may 
also serve as models for permitting authorities to consider in 
programmatic rulemaking. Generally, EPA intends to issue such guidance 
only after providing notice and seeking comment on such monitoring. 
After considering comments received on the monitoring requirements for 
flares in 40 CFR 60.18, EPA is designating, at this time, that 
monitoring as presumptively acceptable. This designation is being made 
in recognition that some published monitoring practices or protocols 
provide sufficient design and monitoring performance specifications to 
satisfy CAM requirements while not fully satisfying the part 64 
definition for a continuous compliance determination method. Some 
presumptively monitoring protocols may include procedures for 
calculating compliance with applicable emission limitations or 
standards but have some portions subject to CAM requirements (e.g., 
monitoring to indicate a reasonable assurance that control device 
efficiency is maintained at an assumed level) as indicated in 
Sec. 64.2(b)(1)(vi) of the rule.
    Reliance on presumptively acceptable monitoring will relieve owners 
and operators of the initial burden of justifying that the monitoring 
selected satisfies part 64. However, this presumption of acceptability 
is rebuttable, and, if information or evidence rebutting the 
presumption is brought forward, the owner or operator must bear the 
burden of justifying that the proposed monitoring complies with part 
64. Final decisions as to the acceptability of monitoring rest with the 
informed discretion of the permitting authority, subject to permit 
review by EPA under 40 CFR 70.8, taking into account any appropriate 
presumption and all other relevant information and data.
    Finally, Sec. 64.4(b) requires the owner or operator to identify 
and explain any changes in manufacturer recommendations or requirements 
applicable to installation, verification and quality assurance of the 
monitoring. As explained above, the Sec. 64.3(b) design criteria allow 
for these differences even though EPA generally requires the owner or 
operator to comply with such provisions. This documentation requirement 
is important to allow an appropriate evaluation of the reasons for 
changing these manufacturer specifications.
    These submittal requirements streamline the similar requirements in 
the 1993 EM proposal. First, Sec. 64.7 of the proposed rule would have 
required that a permit application incorporate a proposed enhanced 
monitoring protocol for every applicable emission limitation or 
standard at each emissions unit subject to the proposed rule. This 
protocol would have had to contain information about and supporting 
documentation for a number of elements, including proposed performance 
specifications, quality assurance procedures, test plans for conducting 
performance verification tests, and a list of all technologically 
feasible monitoring methodologies which could have been employed in the 
proposed protocol. Owners or operators of affected emissions units 
would have also been required to identify new technologically feasible 
monitoring methodologies when submitting a permit renewal application. 
Second, Sec. 64.4(e)(3) of the proposed rule also covered permit 
application submittal requirements. That section would have required 
the owner or operator of an affected emissions unit to submit as part 
of a permit application all of the descriptions, explanations, 
justifications, and supporting data necessary to justify that a 
proposed enhanced monitoring protocol could satisfy the requirements of 
the proposed rule. This section explicitly placed the burden of proof 
on the owner or operator proposing an enhanced monitoring protocol to 
show that the protocol met the rule's requirements.
    A number of commenters raised concerns about these permit 
application requirements. Some argued that the specific information 
requested, such as information pertaining to a parametric relationship, 
may not be available prior to installation of control technology and 
permit issuance. Others contended that the requirements to include 
information on all technologically feasible monitoring methodologies 
was an illustration of a perceived bias towards the use of costly 
continuous emission monitoring methods under the 1993 EM proposal. In 
response to some of these concerns and in furtherance of the goal of 
providing a reasonable assurance of compliance with applicable 
requirements, the Agency has replaced these detailed permit application 
requirements with the provisions described above in the final rule.
    Third, many industry commenters opposed the enhanced monitoring 
protocol selection and proposal requirements in Sec. 64.4(f) of the 
1993 EM proposal. The proposal would have established a procedure for 
the selection of enhanced monitoring protocols that required owners or 
operators to justify the use of a proposed enhanced monitoring protocol 
over other available monitoring methodologies. Under this proposed 
procedure, owners or operators were first directed to consider 
``established monitoring,'' defined as monitoring that had been 
previously demonstrated as a feasible means of assessing compliance at 
a specific emissions unit. An owner or operator could propose to use 
the ``best established monitoring.'' The determination of which 
established monitoring methodology was ``best'' was intended to be an 
evaluation of what type of monitoring was most

[[Page 54925]]

appropriate to determine continuous compliance at a specific emissions 
unit. If no ``established'' monitoring methodology could satisfy the 
performance and operating requirements of the proposed rule, owners or 
operators could propose additions or modifications to an established 
form of monitoring. If no established monitoring methodology applied, 
or if the owner or operator considered the established monitoring 
inappropriate, then an alternative monitoring could be proposed. In 
these circumstances, the proposed rule required the owner or operator 
to identify all monitoring methodologies that were technologically 
feasible for the particular emissions unit, selecting from that list 
the ``best'' methodology for that unit based on a site-specific 
assessment.
    Commenters argued that the requirement to select ``best 
monitoring'' would impose a ``top-down'' selection process with a bias 
towards selection of a CEMS or similar monitoring system. Several 
commenters contended that the legislative history of section 114(a)(3) 
did not support a requirement that the approved enhanced monitoring 
protocol be the ``best'' available. Industry commenters also stated 
that requiring an owner or operator who proposed alternative monitoring 
to list all technologically feasible monitoring methodologies would 
impose unnecessary costs and burdens. Most of those opposing the 
selection provisions suggested that the rule should allow the owner or 
operator to propose any monitoring that met the basic requirements of 
the rule. In the alternative, many commenters suggested making cost an 
explicit criterion in the monitoring selection process.
    Under the CAM approach, the owner or operator may propose any 
monitoring that can meet the design criteria in Sec. 64.3 of the final 
rule. Thus, the comments regarding whether 1993 EM proposal imposed a 
top-down selection hierarchy are no longer relevant.
    In response to the 1996 draft part 64, some commenters objected to 
the need to submit a rationale or justification for the proposed 
monitoring. The Agency disagrees. This information will be necessary 
for the permitting authority, the public, and EPA to judge the 
appropriateness of the proposed monitoring for satisfying the design 
criteria in Sec. 64.3. In addition, this requirement builds on similar 
regulatory precedents in the NSPS and NESHAP programs. Under those 
programs, EPA has routinely required the owner or operator to submit a 
proposed monitoring approach and supporting rationale where the owner 
or operator intends to use a control device for which the underlying 
standard does not contain specific monitoring procedures. (See, e.g., 
40 CFR 60.473(c), 60.544(b), 60.563(e), 60.613(e) and 60.663(e).)
    Commenters on the 1996 part 64 Draft also raised concerns that the 
rule did not contain any provisions promoting the use of existing 
monitoring to satisfy part 64. Clearly, many existing monitoring 
requirements include some degree of monitoring that is used to indicate 
compliance through documenting important operating variables. As such, 
these requirements are generally consistent with the CAM approach. 
Thus, Secs. 64.3(b) and 64.4(b) specifically allow for the owner or 
operator to design and justify proposed part 64 monitoring applying or 
building on existing applicable requirements. The rule uses the phrase 
``in part'' because there is no assurance that the existing monitoring 
necessarily satisfies all of the part 64 design criteria. As described 
above, for certain monitoring that the Agency believes already meets 
the part 64 design criteria categorically, the owner or operator is 
likely to be able to rely completely on those regulatory precedents to 
justify the monitoring proposed to satisfy part 64. The Agency believes 
these provisions adequately provide for the consideration of existing 
monitoring and build upon the ``established monitoring'' concept in the 
1993 EM proposal without the cumbersome selection process hurdles 
included in that proposal.
    Industry commenters on the 1996 part 64 Draft proposed that the 
cost of monitoring that will provide a reasonable assurance of 
compliance be considered in light of the reliability of the pollution 
control technology, the margin of compliance demonstrated for the 
emissions unit, the emissions variability, and the reliability of the 
monitoring. State and local agency commenters noted that a 
demonstration of a credible relationship between parameter monitoring 
and actual emissions was primary in determining a reasonable assurance 
of compliance. These agency commenters also listed reliability of 
monitoring, margin of compliance, and potential emissions variability 
as elements to consider in such a demonstration. The Agency agrees that 
part 64 should enable the owner or operator and the permitting 
authority to consider these factors in developing and approving 
monitoring in a manner that both allows flexibility in design and 
provides a reasonable assurance of compliance. As noted above, the rule 
specifically allows for the use and augmentation of existing monitoring 
in lieu of developing and installing completely new monitoring 
approaches. Further, Secs. 64.3(c) and 64.6(a) of the final rule 
reference the evaluation factors mentioned by both groups of commenters 
to apply in developing and reviewing monitoring to meet part 64 
requirements. The Agency believes that in this manner, the owner or 
operator and the permitting authority can agree on cost-effective 
monitoring that results in the reasonable assurance of compliance 
required by part 64.
2. Documentation and Justification for Indicator Ranges
    Section 64.4(c) of the final rule requires that an owner or 
operator propose indicator ranges supported by data obtained during the 
conduct of the applicable compliance or performance testing at the 
pollutant-specific emissions unit and supplemented, as necessary, by 
engineering assessments and manufacturer's recommendations. An owner or 
operator can satisfy this requirement with existing compliance test 
method data, if applicable. The use of existing data is limited to 
circumstances in which no changes have occurred since the data were 
obtained that could significantly affect the conditions for which the 
indicator ranges were established since the performance testing was 
conducted. Such significant changes include, but are not limited to, an 
increase in process capacity, a modification to the control system 
operating conditions, or a change in fuel or raw material type or 
chemical content. Because of the assurances provided through 
representative performance testing in conjunction with documentation 
provided by the use of engineering and other information, the final 
rule also explicitly states that testing over the entire indicator 
range or range of potential emissions is not required.
    If site-specific compliance testing method data are unavailable, 
Sec. 64.4(c) gives an owner or operator two options. Indicator ranges 
can be based on testing to be conducted pursuant to a test plan and 
schedule for obtaining the necessary data. An owner or operator may 
also choose to rely on other forms of data to establish the proper 
indicator ranges. However, if the owner or operator proposes to rely on 
engineering assessments and other data without conducting site-specific 
compliance method testing, Sec. 64.4(c)(2) requires submission of 
documentation to demonstrate that factors applicable to the owner or 
operator's specific circumstances make compliance method testing 
unnecessary. Section 64.6(b) gives the permitting authority the 
discretion to require compliance

[[Page 54926]]

method testing where necessary to confirm the ability of the monitoring 
to provide data that are sufficient to satisfy part 64.
    These provisions are similar to but are less prescriptive than the 
comparable provisions in the 1993 EM proposal as well as less 
contingent upon a statistical correlation between operational 
parameters and emission levels. Section 64.4(f) of the 1993 EM proposal 
would have operated with proposed Sec. 64.4(b)(2) and appendix C to 
describe all requirements related to performance verification testing 
under the 1993 EM proposal. Section 64.4(b)(2) of the EM proposal 
established a duty under the proposed rule's general performance and 
operating criteria to conduct applicable performance verification test 
procedures in accordance with appendix C. Appendix C of the proposal 
contained specifications on the procedures to be used by an owner or 
operator for validating the representativeness of a monitoring protocol 
and the performance verification procedures for continuous monitoring 
systems. Section 64.4(f) would have required owners to submit with a 
permit application a test schedule and test plan that described the 
procedures, reference methods, test preparations, locations and other 
pertinent information for all required performance verification tests.
    Section 64.4(b)(2) would have required an owner or operator who 
sought to include process or control device parameter monitoring in an 
enhanced monitoring protocol to conduct verification testing in 
accordance with appendix C. Section 7 of proposed appendix C described 
the required procedures for testing the correlation between the 
parameter(s) to be monitored and the applicable emission limitations or 
standards. Section 64.4(f)(1) of the proposed EM rule stated that a 
test plan for parameter monitoring correlation tests must describe any 
significant process or control device parameters not included in the 
proposed enhanced monitoring protocol and must demonstrate that 
excluding such parameters will not adversely affect the validity of the 
correlation. This section also would have required the owner or 
operator proposing the use of parameter monitoring to demonstrate the 
validity of the parameter correlation over the potential range of 
facility operations.
    Industry commenters had a number of objections to and suggestions 
for improvement of the proposed rule's performance verification testing 
requirements and related permit application requirements. To reduce 
costs, some commenters suggested that performance verification tests 
should not need to be conducted under part 64 where adequate prior 
tests have been conducted pursuant to another applicable requirement. 
The Agency agrees and has adopted this approach in the final rule. A 
number of commenters expressed concerns about the level of detail which 
had to be included in the monitoring verification test plan. The EPA 
believes that the documentation provisions of the final rule will 
generally not require the same level of detail that would have been 
required under the proposed rule. Several commenters objected to the 
requirement to account in detail for all potentially significant 
parameters when documenting parameter range correlation testing. The 
Agency has not included a similar explicit requirement in the final 
rule's documentation and testing requirements for the establishment of 
indicator ranges. The Agency does note that an indicator range which 
fails to take into account significant control device parameters is 
unlikely to provide the reasonable assurance of compliance with 
emission limitations or standards required by Sec. 64.3(a).
    Finally, a number of commenters who supported the availability of 
parameter monitoring under the proposed rule stated that the 
correlation testing requirements would be difficult and expensive to 
meet and would discourage source owners or operators from using 
parameter monitoring. In addition, in response to the 1996 part 64 
Draft, a number of commenters opposed the requirement to establish 
indicator ranges by conducting performance or compliance testing. They 
asserted that this either was an improper attempt to revive the 
correlation requirements in the 1993 EM proposal, or unnecessary to 
establish the appropriate range for most parameters.
    As discussed above in Section II.C., the CAM approach builds on the 
premise that if an emissions unit is proven to be capable of achieving 
compliance as documented by a compliance or performance test and is 
thereafter operated under the conditions anticipated and if the control 
equipment is properly operated and maintained, then there will be a 
reasonable assurance that the emissions unit will remain in compliance. 
In most cases, this relationship can be shown to exist through results 
from the performance testing without additional site-specific 
correlation of operational indicators with actual emission values. The 
CAM approach builds on this fundamental premise of the regulatory 
structure.
    However, as raised in the Portland Cement Response to Remand 
discussed in Section II.C., one difficult element of using ``proper 
operation and maintenance'' as a regulatory tool is the potential 
difficulty in determining whether proper operation and maintenance has 
in fact occurred. Thus, a critical issue that the CAM approach must 
address is establishing appropriate objective indicators of whether a 
source is ``properly operated and maintained.'' In developing the final 
rule, EPA looked to past regulatory experience in developing a balanced 
approach to establishing indicator ranges and using the monitoring to 
assure compliance performance.
    In proposing the operation and maintenance requirements in 40 CFR 
60.11(d), EPA required that owners or operators maintain and operate 
their facilities ``in a manner consistent with operations during the 
most recent performance test indicating compliance.'' 38 FR 10821, May 
2, 1973. The obvious rationale behind this original language was that 
if the source was in compliance during the test, and it continued to 
operate its equipment as it was operated during the test, there was a 
reasonable assurance that the source would remain in compliance. This 
language, however, was revised when the rule was promulgated on October 
15, 1973. In the preamble to the promulgated rule, EPA explained that 
the language was changed because of comments which questioned ``whether 
it would be possible or wise to require that all of the operating 
conditions that happened to exist during the most recent performance 
test be continually maintained.'' 38 FR 28565. The EPA therefore 
revised Sec. 60.11(d) to require that source owners or operators 
operate and maintain their pollution control devices ``in a manner 
consistent with good air pollution control practices for minimizing 
emissions.'' Id.
    This regulatory history argues against a strict requirement that 
part 64 require indicator ranges to be related exactly to the operating 
conditions that existed during a performance test. However, in many 
NSPS subparts, and more recently in MACT standards, EPA generally has 
required that operation and maintenance indicators be established 
during an initial performance test, with some allowance for adjusting 
the indicator values observed during the test. For instance, where a 
thermal incinerator is used to comply with a VOC emission limit, the 
NSPS subparts usually require the owner or operator to establish a 
baseline temperature value as an indication of whether the incinerator 
is properly operated and

[[Page 54927]]

maintained. The baseline temperature value is established at a value 50 
degrees Fahrenheit below the average temperature recorded during the 
most recent performance test (see, e.g., 40 CFR 60.615(c)(1).) In 
recent MACT examples, EPA has required the indicator ranges to be 
established during performance testing, but with an allowance to 
supplement the performance test data with engineering assessments; in 
addition, the MACT requirements often state that testing across the 
full range of operating conditions is not required where the indicator 
range is subject to review and approval. (See, e.g., 40 CFR 63.654(f) 
(3)(ii)(A) and 63.1334(c).)
    Based on these NSPS and MACT examples, the presumptive approach for 
establishing indicator ranges in part 64 is to establish the ranges in 
the context of performance testing. To assure that conditions 
represented by performance testing are also generally representative of 
anticipated operating conditions, a performance test should be 
conducted under conditions specified by the applicable rule or, if not 
specified, generally under conditions representative of maximum 
emission potential under anticipated operating conditions. In addition, 
the rule allows for adjusting the baseline values recorded during a 
performance test to account for the inappropriateness of requiring that 
indicator conditions stay exactly the same as during a test. The use of 
operational data collected during performance testing is a key element 
in establishing indicator ranges; however, other relevant information 
in establishing indicator ranges would be engineering assessments, 
historical data, and vendor data. Indicator ranges do not need to be 
correlated across the whole range of potential emissions.
    Finally, because the emissions units subject to part 64 will not 
necessarily be undergoing performance testing absent part 64 (unlike 
the comparable units subject to initial compliance testing under the 
NSPS and MACT programs), the rule does not require establishment of 
indicator ranges during compliance or performance testing but rather 
presumes the appropriateness of doing so. The Agency believes that this 
approach makes part 64 consistent with underlying regulations but with 
appropriate alternatives that reflect the different universe of 
emissions units subject to part 64.

E. Section 64.5--Deadlines for Submittal

    The final rule establishes two alternative schedules for 
implementing part 64 depending on the size of the pollutant-specific 
emissions unit involved. Under Sec. 64.5(a), ``large'' pollutant-
specific emissions units are subject to the shortest implementation 
timetable. ``Large'' units are those that have the potential to emit 
(after controls) the applicable pollutant at or above the major source 
threshold. If the owner or operator has not submitted the permit 
application for the applicable source prior to April 20, 1998, the 
owner or operator must submit proposed part 64 monitoring in the next 
part 70 permit application. If a permit application has been submitted 
by the rule's effective date, but the permitting authority has not yet 
determined by that date that the application is complete, the owner or 
operator will have to supplement the application with the relevant 
information required under part 64. If the application has already been 
found complete, then the part 64 information will generally not have to 
be submitted until the next permit renewal application. In the interim, 
the monitoring requirements adopted by permitting authorities in 
response to the requirements in part 70 will continue to apply.
    There are two circumstances where information must be submitted 
prior to the next permit renewal application. First, if the owner or 
operator submits an application for a significant permit modification 
after April 20, 1998, the owner or operator must submit the appropriate 
part 64 information for any pollutant-specific emissions unit(s) 
covered by the modification. This requirement will assure that 
significant permit revisions affecting particular emissions units are 
not considered in a piecemeal fashion and that part 64 is implemented 
as quickly as reasonably practicable. In response to comments on the 
1996 part 64 Draft, the Agency has limited this provision to only 
significant permit revisions so that part 64 requirements will not 
impede permit revisions made under expedited permit revision processes, 
such as administrative amendments, notice only changes, or de minimis 
permit revision procedures that are under consideration by the Agency. 
Second, if the permit application has been found complete but the 
permit has not issued, and the owner or operator proposes to revise the 
application to include a change of a type that would have been subject 
to the significant permit revision process, had the permit been issued, 
then the owner or operator must include part 64 required information 
for the pollutant-specific emissions unit(s) identified in the 
application revision. This circumstance triggers part 64 implementation 
because this type of permit application revision would require a second 
completeness determination by the permitting authority, and the 
implementation provision of Sec. 64.5(a)(1)(ii) would be applicable.
    Also in response to comments, the final rule does not include a 
provision in the 1996 part 64 Draft that would have required 
implementation prior to permit renewal for certain permit applications 
being processed under a part 70 transition plan for initial permit 
issuance. The Agency believes that this provision unnecessarily 
complicates the part 64 implementation process. The Agency also notes 
that the current part 70 monitoring provisions will continue to apply 
in the interim if part 64 is not implemented until permit renewal.
    For the remaining smaller pollutant-specific emissions units, part 
64 implementation is delayed until permit renewal. This approach was 
suggested in many comments as one way to reduce the implementation 
burdens of the rule. Such an approach will also allow permitting 
authorities and owners or operators to gain experience with 
implementing part 64 for the largest emissions units before having to 
address the more numerous, but in terms of overall site emissions, less 
significant, smaller units. As noted above, permitting authorities can 
use the delay in implementation to develop programmatic requirements 
that can be relied on in proposing and approving part 64 monitoring; 
this approach will be of the most benefit for the smaller emissions 
units that can use these generic requirements to reduce the burdens of 
part 64.
    The phased-in implementation approach embodied in the final part 64 
rule is a departure from the implementation schedule in the 1993 EM 
proposal. The effective date of the proposed rule was to be 30 days 
after publication of the final rule in the Federal Register. The 
proposed rule did not specify how operating permits issued prior to the 
rule's effective date would be treated. The preamble to the proposed 
rule suggested that these situations would be covered by 40 CFR 
70.7(f)(1)(i). Section 70.7(f)(1)(i) requires that an operating permit 
be reopened to address an applicable requirement which becomes 
applicable during the permit term if the permit has a remaining term of 
three or more years. Thus, under the proposed rule, the owner or 
operator of any facility with an operating permit that had a remaining 
term of three or more years after the effective date of part 64 would 
have been required to reopen the permit and

[[Page 54928]]

provide the required part 64 information.
    The Agency considered relying on this part 70 provision to set the 
implementation schedule for the rule, but chose to adopt the phased-in 
approach described above. Thus, the provisions in Sec. 64.5(a) 
supersede the language of Sec. 70.7(f)(1)(i). The part 70 approach 
would have required that a great many operating permits be reopened as 
soon as the rule became effective, while the phased-in approach 
initially focuses on new permit applications. The former is therefore 
more likely to cause initial burdens and delays in the permitting 
program. The Agency believes that the extended implementation timetable 
resulting from the phased-in approach is better suited to facilitating 
implementation through the operating permits program. In the December 
1994 notice reopening the 1993 EM proposal for comment, EPA discussed 
the possibility of using a phased-in implementation approach as well as 
a ``hammer'' provision, which would have required enhanced monitoring 
to be implemented by all affected sources by January 1, 2000. Multiple 
commenters expressed concerns that an absolute deadline of this type 
would cause systemic logjams and delays in the operating permits 
program because it could require numerous permit revisions or 
reopenings outside of the normal permit renewal process.
    In lieu of a ``hammer'' provision and to clarify that the 
monitoring requirements of part 70 apply irrespective of the part 64 
requirements, the Agency has added explicit language to the rule 
stating that prior to approval and operation of part 64 monitoring, 
part 70 monitoring requirements apply. These part 70 monitoring 
requirements continue to apply even after approval and operation of 
part 64 monitoring; however, because part 64 contains applicable 
monitoring requirements sufficient to demonstrate compliance with 
applicable emission limitations or standards, the part 64 monitoring 
requirements can serve in the place of part 70 monitoring requirements.

F. Section 64.6--Approval of Monitoring

    Consistent with the part 64 implementation approach, Sec. 64.6 
requires the permitting authority to approve or disapprove the 
monitoring proposed by the owner or operator. The following discussion 
highlights the key elements of this section and the key issues raised 
during development of the rule.
    1. Approval and Permit Incorporation
    If the monitoring is approved, the permitting authority must act in 
accordance with Sec. 70.6(a)(3) to include appropriate permit terms 
that reflect the part 64 monitoring requirements. The requirements that 
must be reflected in the permit are: the monitoring approach (including 
the basic method, appropriate performance specifications, and required 
quality assurance checks), any specific data availability requirements, 
the indicator range(s), and a general statement that the owner or 
operator will conduct the monitoring, submit reports, maintain records, 
and, if applicable, identify any QIP obligations, all as required by 
Secs. 64.7 through 64.9.
    It is important to note that the rule provides for two different 
options for incorporating indicator range(s) in the permit. First, the 
actual range can be included (such as maintaining temperature of an 
incinerator at or above a specific number). Second, the permit can 
include a statement that describes how the indicator range will be 
established (such as ``The incinerator will be maintained at a 
temperature at or above a temperature which is 50 degrees Fahrenheit 
lower than the baseline temperature recorded during the most recent 
performance test.''). This latter type of condition would allow for 
reestablishment of the indicator range without the need for a permit 
modification. Several commenters raised concerns that there would be a 
need for changes to indicator ranges, especially near the beginning of 
the program, and that requiring permit modifications for all such 
changes would be burdensome and unwieldy. The Agency agrees and 
believes this latter option addresses the commenters' concerns while 
still providing adequate public comment and review on the establishment 
of indicator ranges at specific sources. If this type of approach is 
used, the permit would also need to specify how the permitting 
authority will be notified of the currently applicable indicator 
range(s).
    These provisions are generally the same as required in Sec. 64.8 of 
the 1993 EM proposal, although the requirements have been modified to 
reflect the changes in the design criteria for the monitoring required 
by part 64. The 1995 and 1996 part 64 Drafts included more elaborate 
conditions than are included in the final rule, including certain 
enforceability components that the Agency does not believe are 
necessary for effective implementation of part 64. These deleted 
components include provisions in the 1996 part 64 Draft that would have 
enabled a permitting authority to establish an indicator range as an 
enforceable condition and that would have established a second QIP 
during a permit term as a permit violation.
    Whether the failure to meet an indicator range is an enforceable 
violation will be a matter of examining the relevant underlying 
applicable requirements, as well as the ability of the permitting 
authority to establish that type of requirement as a federally-
enforceable element of a permit pursuant to approved SIP authority or 
as a State-only requirement pursuant to State law. As described above, 
for purposes of part 64, Sec. 64.6 clarifies that the indicator ranges 
or the means by which they are to be established are to be included in 
the permit to indicate when an owner or operator is required to report 
excursions or exceedances. In addition, it should be noted that 
Sec. 64.7 establishes the independent obligation for the owner or 
operator to take appropriate corrective action in response to 
excursions or exceedances that occur.
    The Agency also decided to delete the draft requirement that a 
second QIP during a permit term constitutes a violation. This provision 
was widely criticized by both industry and State commenters. The Agency 
had specifically noted in the discussion accompanying the 1996 part 64 
Draft that it was concerned that this approach may not be appropriate. 
As discussed in Sections II.G. and H., the final rule, consistent with 
the precedent of 40 CFR 60.11(d), provides for the general use of part 
64 data and other information to document that the owner or operator 
has failed to operate and maintain an emission unit properly and 
provides for the QIP mechanism as one option for addressing situations 
in which such a failure has occurred. In that respect, any time a QIP 
is required there will be an underlying finding that the owner or 
operator has failed to take appropriate action and may be subject to 
enforcement for that violation. Thus, there is no need for the final 
rule to include separate enforcement consequences related to multiple 
QIPs.
    The Agency notes that many commenters on the 1996 part 64 Draft 
suggested that the rule would impose too many permit requirements and 
that the permit should merely state that compliance with part 64 is 
required and that the owner or operator will take appropriate action in 
response to the data. Commenters pointed to the requirements for 
startup, shutdown, malfunction plans (SSMPs) under part 63 and section 
112(r) risk management plans (RMPs) required under part 68 as examples 
of this approach to referencing

[[Page 54929]]

applicable requirements in a part 70 permit.
    The Agency disagrees with the approach suggested and the use of the 
SSMP and RMP examples cited in the comments. The two examples both 
involve plans which an owner or operator is required to develop in 
accordance with general criteria but which are not subject to approval, 
although there are provisions which allow EPA or the permitting 
authority to require changes in the plans under certain conditions. 
(See 40 CFR 63.6(e)(3) and 68.220.) The Agency notes that it proposed 
this concept to implementing part 64 in the 1995 part 64 Draft but that 
numerous commenters opposed this approach because there would be no 
final approval process for the monitoring. (See Sec. 64.3(c) of the 
1995 part 64 Draft and the comments in, for example, VI<radical>D-38 
and 45). Many commenters then seemed to request that EPA use the SSMP 
or RMP approach after reviewing the 1996 part 64 Draft.
    After evaluating all of the comments, the Agency believes that part 
64 monitoring should be incorporated into permits in the same fashion 
as all other required monitoring. The following discussion provides a 
list of the various components of the basic monitoring approach that 
need to be incorporated in the permit. To provide a practical example 
of what the ``basic monitoring approach'' entails, the following 
example is based on the use of incineration to control TRS emissions 
from certain affected facilities at kraft pulp mills (see 40 CFR 60.280 
et seq.); the example is intended to indicate the level of detail 
required, and not necessarily the appropriateness of the example 
monitoring for satisfying part 64: ``Company A will monitor the 
combustion temperature in the incinerator at the point of incineration 
of the effluent gases. Combustion temperature will be recorded 
continuously during all periods of incinerator operation using a strip 
chart recorder. Company A will use a 5-minute rolling average of 
combustion temperatures to determine whether an excursion from 
(combustion temperature limit or range) has occurred. The thermocouple 
used to determine the temperature will be accurate to within 1 percent 
of the temperature being measured. Company A will conduct daily 
operational checks of the thermocouple, strip chart recorder, and the 
temperature recording process system. Company A will conduct an annual 
accuracy check of the temperature measurement and recording system.'' 
This example mirrors the basic monitoring information required under 
the relevant portions of subpart BB. Another example that might apply 
in other cases could include a permit condition which: (1) Identifies 
the pollutant-specific emissions unit, (2) states that the owner or 
operator will install, operate, maintain and reduce data from a CEMS 
for that pollutant in accordance with both the general provisions in 40 
CFR 60.13 and the applicable performance specifications in appendix B 
to 40 CFR part 60; and (3) specifies the appropriate period for 
averaging data to determine if an exceedance occurs. That type of 
permit condition would address the components of the basic monitoring 
approach identified above.
    As noted in the above examples, there is no substantive difference 
for how an owner or operator will be required to address existing 
monitoring in a permit versus part 64 monitoring. For the one element 
of the monitoring (indicator ranges) which the owner or operator is 
most likely to need to adjust, especially at the beginning of the 
program, the final rule includes the option discussed earlier that can 
provide the necessary flexibility to adjust indicator ranges without 
the need for a permit revision. Thus, EPA believes that the level of 
detail required in the permit is appropriate and consistent with the 
level of detail originally included in the 1993 EM proposal and 
required for existing monitoring.
2. Approval Prior to Installation and/or Verification
    A number of those commenting on the 1993 EM proposal expressed 
concerns about the costs of installing equipment and performing testing 
for proposed monitoring prior to approval in the permit. The Agency 
understands that an owner or operator may be unwilling to proceed with 
such installation, testing, or other monitor verification activities 
until after the proposed approach to complying with part 64 is 
approved. Under the final rule, these activities may be completed after 
approval of the monitoring. The owner or operator must propose a 
schedule for making the monitoring operational as expeditiously as 
practicable after approval (see Sec. 64.4(e)) and then the permit must 
include an enforceable schedule with milestones that reflect the 
approved schedule. The schedule must provide for the monitoring being 
fully operational as expeditiously as practicable, but in no event more 
than 180 days from the date of issuance of the final permit. The 
general requirements in Sec. 64.7 to operate the monitoring in 
accordance with part 64 will not apply until the final verification is 
complete.
3. Conditional Approval of the Monitoring
    Under Sec. 64.6(b), the permitting authority may condition the 
approval on the owner or operator collecting additional data on the 
indicators to be monitored for a pollutant-specific emissions unit, 
including required compliance or performance testing, to confirm the 
ability of the monitoring to provide data that are sufficient to 
satisfy the requirements of this part, and to confirm the 
appropriateness of an indicator range(s) or designated condition(s) 
proposed to satisfy the design criteria in the rule. Such conditional 
approval should also be consistent with the requirement in the rule 
that monitoring be designed, installed, and begin operation within 180 
days of permit approval.
4. Disapproval of the Monitoring
    If a permitting authority determines that the monitoring proposed 
by an owner or operator fails to satisfy part 64, the permit must 
include monitoring that at a minimum meets the monitoring provisions in 
part 70. Moreover, Sec. 64.6(e)(2) requires the permitting authority to 
impose a compliance plan requirement in the permit which directs the 
owner or operator to repropose monitoring in accordance with Secs. 64.3 
and 64.4 within no more than 180 days after disapproval. Under 
Sec. 64.6(e)(3), the owner or operator will be in noncompliance with 
part 64 if: (1) The owner or operator fails to submit monitoring within 
the required compliance schedule; or (2) the permitting authority 
disapproves the monitoring submitted, subject to the owner or 
operator's right to appeal any such disapproval. Note that the decision 
to disapprove the initially proposed monitoring would also constitute 
final agency action for purposes of appeal.
    This disapproval process was implied but not explicitly addressed 
in the 1993 EM proposal or the subsequent drafts of part 64. However, 
comments on these earlier versions of the rule did raise concerns about 
when an owner or operator could appeal a decision as to the monitoring 
and whether a permitting authority could insert in the permit the 
monitoring which the permitting authority believes should be used. The 
Agency believes that in most cases, the permit process provides ample 
opportunity for the permitting authority and the owner or operator to 
confer about the appropriate monitoring to satisfy part 64 and agree 
upon an approach, with public and EPA review,

[[Page 54930]]

without having to reach the point of disapproving the monitoring in the 
final permit action. Nevertheless, the Agency also believes that the 
final rule should clarify how a monitoring disapproval will be handled.
    The Agency notes further that, unlike the procedures for most 
applicable requirements, the part 70 permit process will be used as the 
process for approving the specific monitoring that is used to satisfy 
part 64. In that respect, the part 70 process will be essential to 
assuring adequate public, permitting authority, and, as necessary, EPA 
input on part 64 monitoring. The Agency believes that the approval/
disapproval procedures in the final rule highlight this important 
aspect of part 64 and will provide for adequate public and EPA review 
of the monitoring used to satisfy part 64.
5. Permit Shield
    The Agency notes that, after approval of the part 64 monitoring in 
a permit, the permit shield provisions in part 70 may extend to the 
part 64 monitoring approved in the permit. A significant area of 
comment on the 1993 proposed EM rule was the effect of implementing 
part 64 on these permit shield provisions. Some commenters were 
concerned that the linking of part 64 and the permitting process would 
hamper the timely processing of permits, and in some cases, result in 
the loss of the permit application shield. The Agency has addressed 
these concerns in the changes to the implementation schedule of the 
final rule. Other commenters suggested that the non-specific nature of 
part 64 monitoring requirements could lead to a situation where the 
permit shield could be lost even if the monitoring was originally 
developed in good faith and was approved by the permitting authority. 
These commenters argued that if such monitoring is later determined to 
be inadequate by the permitting authority or the owner or operator, 
there should be a process for correcting the monitoring without finding 
the owner or operator in violation of the general part 64 substantive 
requirements.
    EPA believes that, if a permitting authority extends the permit 
shield to the monitoring requirements included in an operating permit, 
the owner or operator will be shielded from any retrospective action 
based on a claim that the monitoring approved in the permit fails to 
satisfy part 64 requirements. This protection is only available so long 
as the owner or operator conducts the monitoring in accordance with the 
permit. Also, the shield will not prevent the permitting authority or 
the EPA from reopening the permit if, after approval, the permitting 
authority or the Agency finds cause to reopen the permit based on a 
deficiency in the approved monitoring.
    Where an owner or operator discovers that the originally approved 
monitoring is inadequate, the final rule does require the owner or 
operator to correct the defect in the monitoring expeditiously. Section 
64.7(e) requires an owner or operator to promptly notify the permitting 
authority and submit a proposed modification to the source's part 70 
permit under at least two circumstances. First, if the owner or 
operator documents that a violation of an emission limitation or 
standard occurs but the part 64 monitoring failed to indicate an 
excursion or exceedance for the same period, there will be a need to 
address that type of deficiency. Second, if the results of performance 
or compliance testing document a need to modify the approved indicator 
ranges, that type of correction will also be required. The appropriate 
permit modifications may include monitoring additional parameters, 
increasing monitoring frequency, reestablishing indicator ranges, or 
other changes appropriate for the circumstances.

G. Section 64.7--Operation of Approved Monitoring

1. General Conduct of Monitoring
    As soon as the permitting authority has approved the operating 
permit, Sec. 64.7(a) requires the owner or operator of an affected 
source to begin conducting monitoring of the source in accordance with 
the permit. If the permit includes a scheduled date for the completion 
of testing, installation, and final verification of the approved 
monitoring pursuant to Sec. 64.6(d), then the owner or operator is not 
required to begin conducting monitoring until that completion date. 
This provision does not excuse the owner or operator from complying 
with monitoring required under separate authority if the monitoring 
being used to comply with part 64 is also required under that separate 
authority.
    Section 64.7(b) requires an owner or operator to properly maintain 
the approved monitoring. The provision states that the maintenance and 
operation obligations include an obligation to maintain necessary parts 
for routine repairs of the monitoring equipment.
    Under Sec. 64.7(c), the monitoring must be conducted continuously 
or shall collect data at all required intervals during emissions unit 
operating periods unless the monitoring cannot be conducted because of 
monitor malfunctions, associated repairs or required quality assurance 
or control activities (including, as applicable, calibration checks and 
zero and span adjustments). Data collected during such periods is not 
to be used for purposes of part 64, including data averages and 
calculations, or fulfilling a data availability requirement. Data 
recorded during all other periods is to be used in assessing the 
operation of the control device and associated capture system.
    The Agency notes that the requirements in Secs. 64.7(b) and (c) are 
generally consistent with monitoring requirements promulgated under the 
NSPS program (see 40 CFR 60.13(e)) and the new NESHAP program (see 40 
CFR 63.8(c)(1) and (4)). The obligation to keep parts necessary for 
routine repairs is based on a similar requirement in Sec. 63.8(c)(1). 
The requirement that part 64 monitoring be operational during emissions 
unit operation except during monitor malfunctions and similar events is 
consistent with Sec. 60.13(e) and Sec. 63.8(c)(4). It is important to 
note that this provision does not excuse a failure to comply with a 
data availability requirement. Even if a data availability requirement 
is met, this provision requires an owner or operator to continue 
operating the monitoring unless it is technically infeasible to do so.
    The Agency believes that these general operating requirements were 
implicit in the 1993 EM proposal, including proposed Sec. 64.4(b)(4) 
which required the owner or operator to obtain quality-assured data 
from the monitoring sufficient to satisfy minimum data availability 
requirements. However, EPA notes that in comments on the subsequent 
drafts of part 64, certain commenters objected to these types of 
provisions, and specifically requested that the rule exempt the source 
owner or operator from having to conduct monitoring during periods when 
the source is not required to comply with the underlying standard (such 
as startup and shutdown conditions). The Agency disagrees with these 
comments, and notes that existing general monitoring requirements under 
NSPS and NESHAP do not provide for that type of exception to 
monitoring. In fact, EPA has previously rejected the idea of exempting 
sources from monitoring during startup and shutdown conditions in other 
rulemakings. (See, e.g., Air Oxidation Processes in Synthetic Organic 
Chemical Manufacturing Industry-- Background Information for

[[Page 54931]]

Promulgated Standards, EPA-450/3-82-001b, June 1990, pp. 2-37 and 2-38. 
For a copy of this document, see EPA Air Docket A-81-22-V-B-1.) 
Although compliance with emission limitations may be exempted in some 
circumstances during conditions such as startup and shutdown, an owner 
or operator still is required to operate and maintain a source in 
accordance with good air pollution control practices for minimizing 
emissions during such periods. The monitoring under part 64 is 
essential to evaluate the extent to which this duty is fulfilled. 
Therefore, to clarify the intent of part 64 and assure that it is 
implemented consistently with other EPA monitoring programs, the final 
rule includes these general operating requirements in Secs. 64.7(b) and 
(c).
2. Corrective Action Obligations
    Section 64.7(d) of the final rule requires that, upon detecting an 
excursion or exceedance, the owner or operator will restore the 
pollutant-specific emissions unit to its normal or usual manner of 
operation as expeditiously as practicable in accordance with good air 
pollution control practices for minimizing emissions. This requires 
minimizing periods of startup, shutdown or malfunction, and taking 
corrective action to restore normal operation and prevent recurrence of 
the problem that led to the excursion or exceedance except where the 
excursion or exceedance was related to an excused startup or shutdown 
condition. Corrective action may include inspection and evaluation 
where operations returned to normal without operator action, or any 
appropriate follow up activities, including shutting down a pollutant-
specific emissions unit until necessary repairs are completed, to 
return the operation to within the indicator range or below the 
applicable emission limitation or standard, as applicable. Consistent 
with existing general duty provisions such as Sec. 60.11(d), 
determination of whether the owner or operator has used acceptable 
procedures in response to an excursion or exceedance will be based on 
available information, including monitoring data. A related provision 
found at Sec. 64.8(a) of the final rule provides that a source owner or 
operator can be required to implement a quality improvement plan (QIP) 
after a determination by the permitting authority or the Administrator 
that the source owner has failed to conduct proper operation and 
maintenance as documented through part 64 monitoring and other 
available information (see Section II.H.).
    Because the Agency's emphasis for part 64 monitoring shifted away 
from the direct compliance determination requirements of the 1993 EM 
proposal to the CAM approach, the Agency believes it is critical to 
underscore the need to maintain operation within the established 
indicator ranges. Therefore, the rule includes the requirement to take 
prompt and effective corrective action when the monitored indicators of 
compliance show that there may be a problem. Requiring that owners and 
operators are attentive and respond to the data gathered by part 64 
monitoring has always been central to the CAM approach. Certain 
comments received on the 1996 part 64 Draft questioned the 
appropriateness of the corrective action provisions with some 
commenters finding the requirements unnecessary and others alleging 
that they were inadequate. The Agency reiterates its belief that part 
64 monitoring can provide a reasonable assurance of compliance with 
applicable requirements. This is consistent with the approach suggested 
by many commenters throughout the development of part 64; however, 
because the data will not necessarily allow a direct determination of 
compliance, the Agency believes that it is essential to the CAM goal of 
ongoing compliance operation that part 64 require that owners or 
operators respond to the data so that any problems indicated by the 
monitoring are corrected as soon as possible. Without this corrective 
action obligation, owners or operators might tend to ignore excursions 
because such excursions may not necessarily allow a determination of a 
violation. Thus, EPA believes that the corrective action component of 
part 64 is critical to assuring that the information from the enhanced 
monitoring required by part 64 is heeded by owners or operators.
    As described in the discussion accompanying the 1996 part 64 Draft, 
the Agency did consider requiring owners or operators to specify 
maximum periods for conducting various types of corrective action, but 
stakeholders raised concerns that it would be extremely difficult to 
establish the appropriate time frames for every possible contingency 
(see, e.g., docket items VI-D-45, p. 12; VI-E-9, p. 5-6). The Agency 
continues to agree that it would be difficult to establish appropriate 
time frames for all corrective action scenarios and therefore has 
adopted the general obligation requirement in the final rule. The 
Agency also believes, however, that as situations develop at a 
particular facility it may be possible in subsequent rounds of 
permitting to provide specific timetables for certain high priority 
concerns if a permitting authority desires to make this requirement 
more specific. In addition, if an existing site-specific plan, such as 
a malfunction abatement plan, already establishes required time frames 
for certain types of excursions, the owner or operator or the 
permitting authority could incorporate those specific time frames into 
the permit.
    The obligation to correct excursions as expeditiously as 
practicable is the enforceable component associated with establishing 
an indicator range under part 64. Part 64 does not establish that an 
excursion from an indicator range constitutes an independent violation 
by itself. The 1996 part 64 Draft did provide that the permit may 
specify that an excursion could be considered a failure to satisfy an 
applicable permit term or condition in various situations. First, if 
existing requirements already require the owner or operator to comply 
with the indicator ranges, the 1996 Draft indicated that the ranges 
would be enforceable requirements. Second, the 1996 Draft indicated 
that an owner or operator could propose this approach. Finally, the 
1996 Draft stated that, if consistent with existing authority, the 
permitting authority could specify in the permit that excursions from 
the indicator ranges will be considered enforceable permit deviations. 
In comments submitted during the development of the rule, State and 
local agency organizations stated their support for including control 
device performance indicator ranges as enforceable permit requirements 
even if such indicator ranges are not used directly to determine 
compliance or noncompliance with applicable emission limitations or 
standards. (See, for example, docket item VI-D-49 and IV-D-274). 
However, numerous industry commenters opposed the provisions in the 
1996 part 64 Draft which addressed this issue.
    The Agency has considered all of the relevant comments and has 
determined that part 64 need not address this issue. First, if an 
underlying requirement makes an indicator range enforceable, then that 
will have to be addressed in the permit under the existing requirements 
in part 70. Second, a source owner can always propose to make the 
indicator range enforceable and part 64 need not address this 
possibility. Third, if a State agency has independent authority to make 
indicator ranges enforceable, that can be done irrespective of the 
authority provided in part 64. Finally, as discussed in Section

[[Page 54932]]

I.E., the CE revisions clarify that an excursion from an indicator 
range in some circumstances may be sufficiently probative of compliance 
that it could be used to document a violation of an underlying 
requirement. Based on these considerations, the final rule simply 
requires the permit to establish an indicator range, and then imposes 
the obligation to take appropriate corrective action in response to an 
excursion and to report the excursion in applicable periodic reports 
and compliance certifications.
3. Monitoring Revisions
    Section 64.3(d) of the 1993 EM proposal would have required a 
significant permit modification pursuant to Sec. 70.7 whenever a change 
was made to an enhanced monitoring protocol or whenever a pollutant-
specific emissions unit was modified in such a way as to make an 
existing protocol no longer appropriate. A great number of industry 
commenters objected to the permit modification provisions in the 
proposed rule. The vast majority objected to the scope of this 
provision, under which any change to an enhanced monitoring protocol 
triggered a requirement to obtain a significant permit modification. A 
number of commenters noted that the proposed rule would require 
significant permit modifications for changes that would not have 
triggered such a requirement under part 70 itself.
    The Agency agrees with those commenters that believe the part 70 
procedures generally should be relied on for determining when and what 
type of a permit change is required for different types of monitoring 
modifications. In keeping with this approach, EPA has removed the 
permit modification provisions from the final rule. Instead, the Agency 
intends that permit revisions involving part 64 requirements be made 
pursuant to part 70 permit revision procedures. The EPA has proposed 
revisions to part 70 in order to streamline the existing permit 
modification procedures (see 59 FR 44460, August 29, 1994, and 60 FR 
45530, August 23, 1995). The preamble to those proposed revisions 
discusses what types of permit revisions would be appropriate for 
different types of monitoring changes. The EPA intends to promulgate 
permit revision procedures based on the proposed part 70 revisions that 
will clarify when and how a change in monitoring will trigger the need 
to modify the underlying operating permit.
    As noted in the discussion of the permit shield above, Sec. 64.7(e) 
does require an owner or operator to follow permit modification 
procedures upon discovery of deficiencies in approved part 64 
monitoring. In addition, the part 70 procedures will apply if the owner 
or operator wants to change certain aspects of its approved monitoring, 
or if the owner or operator intends to make certain types of emissions 
unit modifications that could trigger the need for a permit revision to 
address part 64 requirements. For instance, if an owner or operator 
switched from a pollution prevention method of controlling emissions to 
a control device within the definition of part 64, that change could 
impose the part 64 monitoring requirements for a unit which had been 
subject only to part 70 monitoring before the change. In such a case, 
the revised part 70 procedures would require the owner or operator to 
submit a request for a part 70 permit modification which includes 
proposed part 64 monitoring and required supporting documentation.

H. Section 64.8--Quality Improvement Plans (QIPs)

    Requirements for responding to the monitoring data if potential 
control problems are detected have been included in the final rule. 
Requiring that owners or operators are attentive to the data obtained 
by part 64 monitoring and take corrective action when problems are 
detected has always been part of the CAM approach. The discussions 
accompanying the 1995 and 1996 part 64 Drafts describe the CAM approach 
as promoting compliance by making the owner or operator pay attention 
and respond to the monitoring data. Because the approach of 
establishing indicator ranges and then imposing an obligation to 
respond to excursions could potentially allow owners or operators to 
comply with part 64 even though they may be in a near constant state of 
correcting excursions, the related concept of quality improvement plans 
(QIPs) was developed. This concept was designed to avoid perpetual 
corrective action which would frustrate the compliance promotion and 
compliance assurance goals of part 64.
1. QIPs in the 1995 Part 64 Draft
    In the discussion accompanying the 1995 part 64 Draft, the 
requirements for responding to monitoring data were described as 
including: operating ranges for monitored parameters, time periods for 
corrective action in the event discrepancies from the established 
operating ranges occur, and a maximum number of discrepancies from the 
established operating ranges to occur in a reporting period. The 1995 
part 64 Draft provided that source owners could establish this maximum 
number of discrepancies as a not-to-exceed limit or as a requirement 
that, initially, triggers implementation of a QIP. The QIP option would 
require evaluation of why the maximum number of discrepancies was 
exceeded. Based on that evaluation, the QIP would require the owner or 
operator to take steps to improve control performance including 
improved preventive maintenance procedures, process operation changes, 
control system improvements or similar actions.
    The QIP option was described as a means of allowing an owner or 
operator to establish site-specific maximum discrepancy numbers without 
facing automatic enforcement exposure for failure to comply with those 
numbers during the early stages of part 64 applicability/
implementation, while at the same time assuring that a large number of 
discrepancies would trigger additional steps to decrease the incidence 
of reduced control performance. In addition, the 1995 part 64 Draft 
contained limits to guard against the use of an ineffective QIP. Owners 
or operators would be allowed to exceed the maximum number of 
corrective actions trigger twice during a permit term. A third or 
subsequent exceedance of the trigger would have been treated as a 
failure to comply with the requirements of part 64 as well as still 
requiring a QIP to improve control performance. These situations 
potentially would have also required the QIP to be revised to more 
adequately serve its purpose of improved control performance.
    The discussion accompanying the 1995 part 64 Draft noted that the 
provisions on the length of corrective action periods and the maximum 
number of corrective action periods per reporting period provided 
significant flexibility and solicited comment on whether the final rule 
should establish additional objective criteria such as a maximum length 
for corrective actions or a limit on the number of corrective actions 
permitted.
    The Agency received a number of comments on the QIP concept after 
releasing the 1995 part 64 Draft. A number of industry commenters 
supported the QIP concept but raised concerns about the provisions 
limiting the number of allowable QIPs and about the specificity of 
certain requirements.
2. QIPs in the 1996 Part 64 Draft
    In the 1996 part 64 Draft the owner or operator was required to 
implement a QIP if the duration of excursions occurring in any 
reporting period exceeded a set percentage of the operating time for 
the pollutant-specific emissions unit over that reporting

[[Page 54933]]

period, or if the number of excursions exceeded a set percentage of the 
monitored averaging periods during the applicable reporting period. If 
the approved monitoring involved the use of a CEMS or PEMS, then the 
appropriate trigger for a QIP would be exceedances instead of 
excursions.
    The appropriate percentage was to be set in the context of the 
permitting process. The permitting authority was to take into account 
all relevant factors, but the percentage of operating time was not to 
exceed 5 percent. The Agency solicited comment on whether that was an 
appropriate percentage and information that could support another 
percentage limit. An exception was provided in the 1996 part 64 Draft 
for circumstances in which specific applicable requirements established 
a higher percentage. Finally, the draft rule stated that the permit 
must include a condition that in the event that either percent trigger 
was exceeded, the owner or operator would develop and implement a QIP 
that met specific criteria.
    Like the 1995 part 64 Draft, the 1996 part 64 Draft described two 
basic parts of a QIP. The first part would consist of evaluation 
procedures to determine the cause of the excessive number of excursions 
(or exceedances, if applicable). Based on that evaluation, the owner or 
operator would develop the second part of the QIP. The second part 
would detail the steps the owner or operator would take to improve the 
quality of control performance, and the schedule for taking those 
steps. Again, depending on the nature of the problem, the appropriate 
steps could include improved preventive maintenance procedures, process 
operation changes, control system improvements or similar types of 
steps. In conjunction with those procedures, the QIP also might include 
improved monitoring procedures.
    The discussion accompanying the 1996 part 64 Draft described these 
requirements as assuring that the monitoring conducted under part 64 
would result in owners or operators taking the necessary steps to 
prevent pollution through reasonable optimization of control 
performance. The Agency stated in that discussion and the draft itself 
that compliance with a QIP is not a substitute for compliance with 
underlying applicable requirements, including general duties to operate 
and maintain facilities in accordance with good air pollution control 
practices, and the 1996 part 64 Draft also required the owner or 
operator to report as a deviation any period during which a QIP is 
being implemented.
    Again the Agency expressed concern about owners or operators 
performing repeated QIPs, and the 1996 part 64 Draft provided that the 
necessity to implement a second QIP for the same pollutant-specific 
emissions unit during the same permit term would constitute a specific 
permit term violation. The Agency acknowledged that an enforceable 
permit condition placing a limit on the number of QIPs might be 
perceived as an unnecessary restriction on the operation of highly 
efficient and well-operated control measures. The EPA noted that a high 
level of excursions could result from tightly set indicator ranges that 
are not at all indicative of potential excess emissions, and that the 
``second QIP as a violation'' approach could inappropriately put an 
owner or operator in violation under such circumstances.
    The Agency then noted that the second QIP as a deviation approach 
might encourage source owners to set unrepresentatively broad indicator 
ranges and thereby avoid excursions. The Agency sought comment on other 
means to encourage the setting of the indicator ranges in a manner 
consistent with the best level of emissions control that can be 
achieved. As one possible alternative, EPA suggested that instead of a 
permit violation associated with the need to implement a second QIP the 
final rule could instead require that the second QIP be implemented 
only through a permitting authority approval process. Such a plan could 
also include restricted process operations until completion of the 
approved QIP. The agency also suggested as a second possible 
alternative that the time period for limiting the owner or operator to 
one QIP could be reduced from the 5-year permit term to 3 years or 
other appropriate period.
    In addition, the 1996 part 64 Draft contained a number of other 
QIP-related requirements. First, it required the owner or operator to 
notify the permitting authority within 2 days after determining that a 
QIP is necessary. Second, the QIP would not become part of the permit 
and would not require permitting authority approval. Third, the QIP was 
to be implemented as soon as practicable, and completed within 180 days 
from the date notice of the QIP was given to the permitting authority. 
Exceptions to the 180-day limit were to be granted only after the owner 
or operator obtained a site-specific resolution and affirmative 
approval from the permitting authority or, if necessary, the EPA of a 
plan to complete the improvement activities. An approved extension 
could include an enforceable, site-specific schedule with milestones 
and completion dates.
    The 1996 part 64 Draft also required the owner or operator to 
report on the activities taken in conjunction with a QIP. QIP 
activities would be summarized in the semiannual report covering the 
period in which the QIP began, and in any subsequent semiannual reports 
covering periods during which the QIP continued. In addition, the owner 
or operator was required to maintain a copy of the QIP and records of 
QIP implementation activities for a period of five years in accordance 
with part 64 recordkeeping provisions.
    Finally, a QIP could lead to changes in previously approved 
monitoring or other changes at the source that require a permit 
revision. Therefore, the 1996 part 64 Draft required the owner or 
operator to submit a proposed revision to the approved monitoring in 
these circumstances. Even if such changes did not require a permit 
revision, a source owner or operator who intended to retain the 
previously approved monitoring was required to reestablish the 
rationale that justified the monitoring.
3. QIPs in the Final Rule
    In response to comments received on the 1995 and 1996 part 64 
Drafts, Sec. 64.8 of the final rule reflects a number of significant 
changes to the QIP requirements.
    A number of commenters challenged the 5 percent QIP trigger in the 
1996 part 64 Draft and some questioned whether a single percentage 
threshold was appropriate regardless of exactly where the threshold was 
set. Section 64.8(a) of the final rule provides that a QIP trigger may 
be set in the permit but does not require it. Where such a trigger is 
used, a level of 5 percent is suggested as a potentially appropriate 
threshold. The final rule also provides that a QIP can be required 
after a determination by the permitting authority or the Administrator 
that an owner or operator has failed to conduct proper operation and 
maintenance as documented through part 64 monitoring and other 
available information. In this respect, the QIP provisions are 
analogous to existing corrective action remedies available to address 
compliance problems.
    Commenters also argued that the 180-day limit for completion of a 
QIP that was included in the 1996 draft part 64 was not reasonable, 
with various commenters arguing for more or less time. Some commenters 
also noted that QIPs that lead to the need for a permit modification 
would be particularly

[[Page 54934]]

problematic in terms of meeting a specific deadline. Section 64.8(c) of 
the final rule requires owners or operators to complete any QIP as 
expeditiously as practicable and to notify the permitting authority if 
they determine that a QIP will take longer than 180 days rather than 
establishing a specific amount of time within which the QIP must be 
completed.
    Many commenters objected to the requirement that a second QIP 
within a permit term be treated as a violation. A number of commenters 
pointed out that a subsequent QIP might be completely unrelated to the 
first QIP, that more room for error should be allowed in the early 
stages of part 64 applicability/implementation, and that the existence 
of such penalties would frustrate the goals of part 64 by discouraging 
source owners from setting indicator ranges at levels that would 
provide early warning of problems. Commenters also noted generally in 
other comments on part 64 that the Agency should consider the part 63 
startup, shutdown, malfunction plan (SSMP) requirements as an 
appropriate precedent for implementing part 64. Based on EPA's 
consideration of the comments, EPA has deleted the concept that a 
second QIP during a permit term is a violation. Instead, the final rule 
allows permitting authorities to use recurring problems as an 
indication that a QIP should be required in order to bring about 
improvements in control device operation and maintenance. In addition, 
the final rule provides that the permitting authority or the 
Administrator may follow up on QIPs and make changes to the plan if the 
QIP has not addressed the problem adequately. This latter requirement 
is analogous to the comparable procedures for requiring changes to 
SSMPs pursuant to Sec. 63.6(e)(3).
    Other changes made in response to comments received on the 1996 
part 64 Draft include deleting the requirement that source owners 
notify the permitting authority within two days of the need to 
implement a QIP, the requirement that periods during which an owner or 
operator is implementing a QIP be reported as deviations in monitoring 
reports and compliance certifications, and the requirement to report 
test method results after QIP implementation. The Agency does not 
believe that these draft requirements are necessary, especially given 
that under the final rule, QIPs generally will be implemented only 
after a determination that an owner or operator has failed to meet a 
general duty to properly operate and maintain a source.
    Some commenters objected to the requirement that owners or 
operators state that a QIP has reduced the likelihood of similar 
problems occurring in the future. The Agency believes that this type of 
information is appropriate, but has changed the final rule so that 
rather than a certification-style requirement, the owner or operator is 
required to submit documentation that the QIP has been completed and 
reduced the likelihood of similar levels of excursions or exceedances 
occurring. This provision will provide the permitting authority with 
the information necessary to gauge the completion of a QIP and whether 
follow-up is necessary.
    Commenters on the 1996 part 64 Draft also requested that an owner 
or operator be allowed to implement a QIP that involves only monitoring 
changes. The Agency notes that the final rule, like the 1996 part 64 
Draft, does not provide for QIPs that address monitoring only. This 
type of change should not be made through a QIP. By its nature, a QIP 
focuses on situations where the owner or operator has failed to meet 
its obligation to properly operate and maintain a source. The QIP 
requirements in the final rule clarify this approach and no longer 
mandate that a QIP be implemented solely because a set duration of 
excursions or exceedances occurs. A source owner who needs to change 
approved part 64 monitoring can address any monitoring problems 
directly through the appropriate permit modification process. For 
indicator range changes, the final rule allows owners or operators to 
avoid the need for a permit modification by specifying in the permit 
the method by which such ranges will be established rather than the 
actual ranges. See Section II.F. for further discussion of that issue.

I. Section 64.9--Reporting and Recordkeeping Provisions

    Part 64 generally relies on the requirements for reporting, 
compliance certification, and recordkeeping already established in part 
70. Beyond general compliance with the part 70 requirements, 
Sec. 64.9(a)(2) clarifies that part 70 reports that involve part 64 
monitoring data must identify summary data on the number, duration and 
cause of: excursions from indicator ranges; emission limit exceedances; 
any corrective actions taken; and monitor downtime incidents other than 
those associated with daily calibration checks. If applicable, the 
report must also document QIP implementation and completion activities. 
See Section II.H. for further discussion of this QIP reporting 
provision.
    The Agency believes that the additional information that is 
required to be reported under part 64 is consistent with streamlined 
reporting requirements under other monitoring programs (such as NSPS 
reporting under 40 CFR 60.7(d)). The Agency also believes that this 
information is necessary to allow permitting authorities to use part 64 
data to track overall control performance and assure that owners or 
operators are operating part 64 monitoring appropriately and responding 
appropriately to excursions from established indicator ranges.
    The recordkeeping requirements similarly require the owner or 
operator to maintain records in conformance with part 70. The 
provisions clarify what part 64 records need to be maintained and the 
acceptable formats for recordkeeping.
    The Agency solicited and received comments on several aspects of 
the reporting and recordkeeping requirements that were included in the 
1993 EM proposal. Those requirements, comments and the changes made by 
EPA in response to the comments are described below.
1. Commencement of Reporting Duty
    Under the 1993 EM proposal, affected owners or operators were 
required to submit ``enhanced monitoring reports.'' These enhanced 
monitoring reports would have fulfilled essentially the same function 
as the part 70 reports required by Sec. 70.6(a)(3)(iii)(A), providing 
permitting authorities with more regular data on monitoring compliance 
than is required under other provisions. The 1993 EM proposal required 
submission of these reports ``[o]n and after the effective date of this 
part * * * .'' Commenters were concerned that this language could be 
interpreted to require reporting prior to approval of a monitoring 
plan. They contended that it would be difficult, if not impossible, to 
fulfill the reporting requirement without knowledge of what monitoring 
would ultimately be required. The Agency agrees with these concerns. 
The final part 64 rule clarifies that the obligation to begin reporting 
does not commence until the specified date by which the owner or 
operator must begin monitoring under part 64.
2. Reporting Frequency
    The 1993 EM proposal also required quarterly submission of the 
above-mentioned enhanced monitoring report for each enhanced monitoring 
protocol. Many commenters argued that quarterly reporting would be too 
costly and/or burdensome. The quarterly reporting requirement is 
eliminated in the final

[[Page 54935]]

rule. By explicitly relying on part 70 reporting requirements, the 
Agency has adopted a requirement that reports be submitted at least 
semiannually. The EPA believes that the minimum part 70 reporting 
frequency is sufficient to meet the goals of compliance assurance 
monitoring without imposing undue costs or burdens on affected sources. 
The Agency also notes that the 1993 EM proposal justified quarterly 
reporting in part on the similar provision that existed at that time in 
part 60 for quarterly reporting of direct compliance data. The Agency 
has since modified part 60 reporting provisions and no longer requires 
quarterly reporting where the source remains in compliance. (See 
Sec. 60.7(e) added at 59 FR 12417, March 16, 1994.) The Agency also 
notes that part 70 authorizes permitting authorities to require more 
frequent reporting of monitoring data, when appropriate.
    A related provision in the 1993 EM proposal required that each 
enhanced monitoring report be postmarked no later than thirty days 
after the last day of the reporting period. A number of commenters 
objected to this due date provision, arguing that thirty days was 
insufficient time to analyze and verify the necessary data and to then 
assemble a report reflecting that data, especially where such data is 
received from independent laboratories. Although the Agency believes 
that thirty days is generally sufficient time to compile the reports 
required under the revised part 64, the due date provision has been 
eliminated. Instead, by relying on the reporting requirements of part 
70, the Agency requires ``prompt'' submission of monitoring reports as 
defined by the permitting authority.
3. Report Signature Requirement
    The 1993 EM proposal required that certification by a responsible 
official be included in each enhanced monitoring report. Under this 
requirement the official had to certify by his or her signature that he 
or she had personally examined the information contained in the report 
and its attachments, that the statements and information were true to 
the best of his or her knowledge and belief, and that he or she was 
aware of the penalties (including the possibility of fine or 
imprisonment) that could accrue for submitting false statements and 
information or omitting required statements and information. A number 
of commenters were concerned that the requirement that an official 
personally examine all information in the report and its attachments 
was impractical, given the amount of data that would have to be 
examined and the responsible official's probable lack of expertise in 
the specific areas of the documents. Commenters also expressed concerns 
that the penalty language of the proposed rule imposed liability on the 
responsible official instead of the persons who might be responsible 
for violations, or on the company itself.
    The EPA has eliminated the proposed report signature requirement in 
the final rule. Instead, part 64 reporting will be subject to the same 
certification requirements as required for all reports submitted under 
Sec. 70.5(d). The Agency believes the use of the part 70 signature 
requirements is appropriate given the general reliance on part 70 
reporting requirements in part 64.
4. Confidentiality of Report Information
    The 1993 EM proposal explicitly provided that an owner or operator 
could assert a confidentiality claim for information reported under 
part 64 to the extent such information was entitled to protection under 
section 114(c) of the Act. This provision received a generally 
favorable response from industry commenters, some of whom proposed that 
the confidentiality provisions be expanded. This provision is not 
included in Sec. 64.9 of the final rule. As noted above, part 64 
reporting is governed by part 70. Information submitted under part 70 
reporting requirements is already subject to confidentiality protection 
pursuant to Sec. 70.4(b)(3)(viii), as well as section 503(e) of the 
Act. Any such information accompanied by a claim of confidentiality 
will be treated in accordance with the regulations of 40 CFR part 2. 
The Agency believes that the inclusion of confidentiality provisions in 
part 64 is unnecessary due to the applicability of the protections 
contained in part 70.
5. Recordkeeping Requirements
    Section 64.9(b)(1) requires owners and operators of affected 
sources to comply with the recordkeeping obligations set forth in 
Sec. 70.6(a)(3)(ii). Part 70 requires that records of the required 
monitoring including the following information be maintained for a 
period of at least five years: The date, place, and time of sampling or 
measurements; the date(s) analyses were performed; the company or 
entity that performed the analyses; the analytical techniques or 
methods used; the results of such analyses; and the operating 
conditions as existing at the time of sampling or measurement. Section 
64.9(b) clarifies that for purposes of part 64, the records to be 
maintained include: Monitoring data, monitor performance data, 
corrective actions taken, the written quality improvement plan and 
related implementation activities, and other supporting information 
required to be maintained under part 64. The Agency notes that the part 
64 requirement to keep these records is not a separate recordkeeping 
requirement. The Agency believes all of these records are already 
required to be maintained under the general part 70 provisions, but 
includes these specific types of records in the final rule to clarify 
the general part 70 language.
    Recordkeeping requirements under the final rule are not 
significantly different from those in the 1993 EM proposal. Although 
the 1993 EM proposal did not explicitly refer to part 70 recordkeeping 
provisions, its requirements were essentially a restatement of part 70 
requirements in an enhanced monitoring context. Owners or operators 
would have been required to maintain the same general information 
required by part 70 for the same minimum period of five years. The 
preamble to the 1993 EM proposal did state that the requirements were 
``consistent with the minimum recordkeeping provisions in 40 CFR 
70.6(a)(3).''
    Both the requirements of the 1993 EM proposal and the currently 
applicable part 70 provisions require the maintenance of records for a 
period of at least five years from the date of the monitoring sample, 
measurement, report or application. A number of commenters expressed 
objections to the five year data retention period, arguing that the 
burden of retaining records for such an extended period was excessive. 
Among the proposed alternatives were a 3-year data retention period, 
consistent with the Acid Rain Program, or a shorter period for records 
covering periods for which there were no deviations. The EPA had 
included the 5-year period in the 1993 EM proposal to be consistent 
with the minimum requirements of Sec. 70.6. The Agency continues to 
believe that this period is appropriate, as part 70 has established the 
5-year retention period as the standard even where less than five years 
is required in underlying rules. For example, part 70 has changed the 
record retention time for NSPS and similar provisions, establishing the 
5-year period for such provisions. By explicitly relying on part 70 
recordkeeping requirements, the Agency has further affirmed the 
appropriateness of employing the 5-year period for part 64 records.
    Section 64.6(b) of the 1993 EM proposal stated that records had to 
be available for inspection at the site of an affected source or at a 
different site approved by the permitting authority. In

[[Page 54936]]

addition, the proposed rule required that such records be maintained so 
as to permit prompt submittal if requested by EPA or the permitting 
authority. A number of commenters on the 1993 EM proposal and the 1996 
part 64 Draft recommended that owners or operators should be free to 
decide where facility records would be kept, arguing that permitting 
authority approval should not be required since most facilities cannot 
handle the storage of the data required by the rule. Because the final 
rule relies directly on the reporting and recordkeeping requirements of 
part 70, the requirement that source owners get permitting authority 
approval for off-site storage of part 64 records has been deleted.
    The recordkeeping provisions of the 1993 EM proposal did not 
specifically address the form in which records must be maintained. 
Several commenters supported the idea of storing data in a non-paper 
media such as microfiche or a form of electronic data storage. They 
contended that such storage methods would reduce the costs and burdens 
associated with storing records for the minimum 5-year period. The 
Agency agrees with these comments and encourages the use of alternative 
recordkeeping, provided appropriate safeguards are adopted to insure 
the integrity and accessibility of the data over time. Section 
64.9(b)(2) of the final rule therefore explicitly allows the 
maintenance of records on alternative media, such as microfilm, 
computer files, magnetic tape disks, or microfiche, so long as the data 
are readily available for inspection and review and the alternative 
format does not conflict with other applicable recordkeeping 
provisions. This approach is consistent with recent general 
recordkeeping provisions, such as the NESHAP general provisions in 40 
CFR 63.10(b).

J. Section 64.10--Savings Provisions

    Because part 64 requirements may overlap with many other applicable 
requirements, Sec. 64.10 of the final rule clarifies that nothing in 
part 64 is intended to excuse the owner or operator from applicable 
requirements under the Act (including emission limitations or standards 
as well as other monitoring requirements) or to restrict the authority 
of the EPA or the permitting authority to impose additional monitoring 
under the Act or State law, as applicable. For example, it would be 
possible for a source to be in compliance with its QIP, but out of 
compliance with an applicable emission limitation or standard. The 
owner of such a source could expect enforcement action for violation of 
the applicable emission limitation or standard, even though there may 
not be a violation of part 64. Simply put, adherence to a QIP does not 
insulate an owner or operator against enforcement action for violations 
of an underlying emission limitation or standard. This section also 
clarifies that the requirements may not be used to justify the 
imposition of less stringent monitoring under other programs than would 
otherwise be required under those programs. For instance, in acting on 
a new source review permit under title I of the Act, the part 64 
requirements may not be used to judge the adequacy of the monitoring in 
that permit; instead, the general procedures and practices under the 
title I permit program will be used.
    The 1993 EM proposal contained specific savings provisions in the 
applicability section (then Sec. 64.1) and the permit application 
section (then Sec. 64.7). The applicability savings provision in 
proposed Sec. 64.1(d) clarified that nothing in part 64 was intended to 
excuse owners or operators from other monitoring, recordkeeping and 
reporting requirements that apply pursuant to other provisions of the 
Act, or to restrict the authority of the Administrator or permitting 
authority to impose additional or more restrictive monitoring, 
recordkeeping or reporting requirements under other provisions of the 
Act. The permit application provision in proposed Sec. 64.7(d) stated 
that owners or operators must still comply with all other permit 
application requirements and requirements established by federal 
regulations or by permitting authorities under federally-approved 
permit programs. These savings provisions are brought together in a 
single section of the final rule without significant changes from the 
original proposal.
    Section 64.10 of the final rule also states that nothing in part 64 
will interfere with the permitting authority's or EPA's ability to 
enforce against violations of applicable requirements under the Act or 
the authority of a citizen to enforce against violations pursuant to 
section 304. This savings provision was added to the final rule to 
clarify the Agency's position on the relationship of part 64 to certain 
enforcement issues. A number of commenters requested that EPA include a 
provision that would shield owners or operators who comply with part 64 
from enforcement for violations of their emission limits. As discussed 
in Section I.E.3., the Agency disagrees with this concept. In cases 
where the part 64 data indicate noncompliance with emission limits, 
including exceedances, permitting authorities and the Agency will be 
able to take enforcement action. In other cases, where the part 64 
monitoring indicates, but does not directly establish, the compliance 
status of a source, the reasonable assurance of compliance based on 
part 64 data does not prohibit the Agency from taking appropriate 
investigatory or enforcement steps when noncompliance is shown by other 
means. This same point was clarified in the discussions accompanying 
both the 1995 and 1996 part 64 Drafts.

K. Revisions to 40 CFR Part 70 and Part 71

    The final rule includes revisions to parts 70 and 71 to clarify the 
relationship between part 64 and the operating permits program. These 
revisions are outlined below.
1. Monitoring Requirements
    The revisions to part 70 allow for streamlining multiple monitoring 
requirements if the streamlined monitoring is able to assure compliance 
at least to the same extent as the applicable requirements not included 
as a result of the streamlining. The Agency notes that the language in 
these revisions is designed to be consistent with a discussion in 
section A.5. of White Paper 2 (See docket item VI-I-2) concerning the 
possibility of streamlining applicable monitoring and testing 
requirements (``Sec. 70.6(a)(3) appears to restrict streamlining by 
requiring that all ``applicable'' monitoring . . . requirements be 
placed in the permit. . . . The EPA intends to revise part 70 to 
reflect this understanding in a future rulemaking.''). The Agency 
indicated in the 1996 part 64 Draft that it intended to fulfill its 
intent to modify part 70 as discussed in White Paper 2 by including the 
appropriate revisions to Sec. 70.6(a)(3)(i) in conjunction with the 
part 64 rulemaking. Because the Agency received strong support for this 
proposed action and no negative comments, the Agency has proceeded to 
add this part 70 revision (and the corresponding revision to part 71) 
as part of this rulemaking.
2. Compliance Certification Requirements
    To tailor compliance certification to the monitoring imposed by 
part 64, EPA has revised Sec. 70.6(c)(5)(iii) (and 
Sec. 71.6(c)(5)(iii)) so that a compliance certification includes the 
following elements.
    First, the permit conditions being certified must be identified. 
Second, the method(s) and other information used to determine 
compliance status of each

[[Page 54937]]

term and condition must be identified. These method(s) will have to 
include at a minimum any testing and monitoring methods identified in 
Sec. 70.6(a)(3) that were conducted during the relevant time period. In 
addition, if the owner or operator knows of other material information 
(i.e., information beyond required monitoring that has been 
specifically assessed in relation to how the information potentially 
affects compliance status), that information must be identified and 
addressed in the compliance certification. This requirement merely 
emphasizes the general prohibition in section 113(c)(2) of the Act on 
knowingly making a false certification or omitting material information 
and the general criminal section on submitting false information to the 
government codified at 18 USC 1001. The revised part 70 provision does 
not impose a duty on the owner or operator to assess every possible 
piece of information that may have some undetermined bearing on 
compliance. The description of the methods relied on by the source 
owner also will have to indicate whether the methods provide continuous 
or intermittent data. In accordance with section 114 of the Act that 
specifies that the certification include whether compliance is 
continuous or intermittent, the Agency will interpret the compliance 
certification that is based on monitoring that provides intermittent 
data as compliance on an intermittent basis.
    Third, the responsible official will have to certify compliance 
based on the results of the identified methods. The certification must 
state the compliance status with the part 70 permit, taking into 
account any deviations and noting as possible exceptions to compliance 
any deviations or excursions/exceedances as defined in part 64 or other 
underlying applicable requirements. Because ``deviation'' was defined 
under part 71 as originally promulgated, the revisions to part 71 
incorporate the concepts of excursion and exceedance into the 
Sec. 71.6(a)(3) definition of ``deviation.'' Therefore, unlike the part 
70 revisions, the revised compliance certification provision in part 71 
refers only to ``deviations.''
    The owner or operator may include information in the certification 
to document that compliance was achieved during any periods in which a 
possible exception is noted (such as information that an excursion or 
exceedance occurred during a period of startup or shutdown for which 
compliance with an emission limitation or standards was excused). The 
requirement to take into account deviations, excursions, and 
exceedances together with the requirement to identify whether the 
method used provides continuous or intermittent data ensures that the 
compliance certification will show whether compliance is continuous or 
intermittent. For example, a compliance certification based on a method 
providing intermittent data or that notes any deviations or certain 
possible exceptions to compliance as a result of exceedances or 
excursions based on monitoring required by this rule will be 
interpreted as showing intermittent compliance. The Agency does not 
interpret a certification of intermittent compliance to necessarily 
mean that the responsible official is certifying that there are periods 
of noncompliance. Such a certification can mean that there are periods 
of time in which the source's compliance status is unknown. When a 
responsible official certifies compliance based on a method providing 
continuous data and no deviations, excursions, or exceedances have 
occurred (or all such occurrences have been adequately addressed by 
other information, as explained above), this will be interpreted as a 
certification of continuous compliance. These provisions implement the 
requirements in section 114(a)(3)(B), (C), and (D) that the 
certification include the methods used to determine the compliance 
status and whether compliance is continuous or intermittent.
    The certification also will have to include any other facts 
required by the permitting authority. This requirement is already 
included in parts 70 and 71 as promulgated. Finally, the Agency notes 
that the rule allows the owner or operator to cross-reference the 
permit or previous reports to identify the various information elements 
required in a certification. This provision allows the actual 
certification to be a short, concise compliance statement that is not 
burdened by restating detailed information that has already been 
provided.
    The goal of part 64 is to provide improved compliance data for 
significant emissions units at title V major sources. This improvement 
will in turn provide additional data for the owner or operator to rely 
on in certifying compliance. As discussed in Section I.C. above, EPA 
believes that the part 64 data will provide a reliable means for owners 
or operators to reach a conclusion about their compliance status. 
However, since the part 64 data will not necessarily always provide 
unequivocal proof of compliance or noncompliance (as a performance or 
compliance test method would), there will be excursions or exceedances 
identified through part 64 which raise questions about compliance 
status but may not confirm conclusively that a source is in 
noncompliance. The existence of these occurrences only indicates the 
need to review the compliance information provided in order to 
determine what, if any, compliance or enforcement actions may be 
warranted.
    These changes to parts 70 and 71 have been developed based on the 
provisions included in the 1993 EM proposal, as supplemented by the 
December 1994 reopened comment period, as well as based on the 1995 and 
1996 part 64 Drafts. The reporting requirements of the 1993 EM proposal 
would have required that a responsible official for an affected source 
use enhanced monitoring data as the basis for the required title V 
compliance certification. The 1993 EM proposal also required the use of 
any other data collected for the purpose of determining compliance 
during the monitoring period. These provisions were the subject of 
significant public comment. Some of these comments seemed to be based 
on the belief that the proposed rule created a separate compliance 
certification requirement. The EPA always intended for these provisions 
to operate within the title V compliance certification process, 
establishing additional requirements that units subject to part 64 had 
to meet in order to satisfy title V compliance certification 
requirements. To clarify this approach, the compliance certification 
provisions in the final rule were removed from part 64. Instead, 
Sec. 70.6(c)(5)(iii) of part 70 (and the corresponding section in part 
71) has been amended to reflect the requirements of compliance 
certification for those units subject to part 64.
    In addition, as discussed above in Section I.C., EPA reopened the 
public comment period on the 1993 EM proposal and stated EPA's intent 
that it may reconsider how to interpret the meaning of ``continuous or 
intermittent'' in the context of certifying compliance. The revisions 
to parts 70 and 71 in today's rulemaking reflect the position taken by 
EPA in that December 1994 notice. Finally, the revisions reflect the 
position taken in the final part 64 rule that monitoring data that do 
not constitute formal performance or compliance test method data may 
still be used by the owner or operator to determine compliance status 
and to note any possible exceptions to compliance that are indicated by 
the monitoring. This interpretation is consistent with the existing 
part 70 which specifically references the fact that a certification 
must consider all of the relevant data

[[Page 54938]]

under Sec. 70.6(a)(3), which includes non-test method monitoring data. 
Because of the possible misinterpretations of the existing language, 
EPA believes that clarifying the compliance certification requirements 
in conjunction with promulgating part 64 is appropriate.

III. Administrative Requirements

A. Docket

    The EPA is relying on the procedural requirements of section 307(d) 
of the Act for the regulations. In accordance with those requirements, 
EPA has established docket A-91-52 for the regulations. The docket is 
an organized and complete file of all the information submitted to, or 
otherwise considered by, 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. The docket is available for public 
inspection at EPA's Air Docket, which is listed under the ADDRESSES 
section of this notice.

B. Executive Order 12866

    Under Executive Order 12866 (58 FR 51735, October 4, 1993), EPA 
must determine whether a regulatory action is ``significant'' and 
therefore subject to Office of Management and Budget (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:
    (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.
    EPA assumes as the baseline for its analysis of part 64 that 
affected emissions sources are currently in compliance with their 
underlying emission standards 100 percent of the time. Thus, there are 
no emissions reductions benefits (and health and welfare benefits), nor 
costs for additional control technology, operation and maintenance, 
associated with part 64. EPA believes that some sources, in response to 
monitoring data gathered under part 64, may indeed have to make 
investments in control equipment technology, operation and maintenance 
to reduce emissions to comply with their underlying emissions 
standards; however, EPA believes these emission reductions benefits and 
costs are not attributable to part 64--but to the underlying emissions 
standards. As such, EPA has not estimated the benefits or costs that 
may result from such actions to reduce emissions.
    EPA has estimated the cost of part 64 to include the cost of 
development and implementation of CAM plans, $50 million per year. 
($1995). This includes the cost of determining the monitoring approach 
and implementing the approved design, including reporting, 
recordkeeping, and certification activities.
    Pursuant to the terms of Executive Order 12866, it has been 
determined that this rule is a ``significant regulatory action'' due to 
its policy implications and was submitted to OMB for review. Any 
written comments from OMB to EPA and any written EPA response to those 
comments are included in the docket. The docket is available for public 
inspection at EPA's Air Docket Section, which is listed in the 
ADDRESSES section of this preamble. The Regulatory Impact Analysis 
(RIA) for this rulemaking is included in the docket.

C. Unfunded Mandates Act

    Section 202 of the Unfunded Mandates Reform Act of 1995 (``Unfunded 
Mandates Act'') (signed into law on March 22, 1995) requires that the 
Agency must prepare a budgetary impact statement before promulgating a 
rule that includes a Federal mandate that may result in expenditure by 
State, local, and tribal governments, in the aggregate, or by the 
private sector, of $100 million or more in any one year. The budgetary 
impact statement must include: (i) Identification of the Federal law 
under which the rule is promulgated; (ii) a qualitative and 
quantitative assessment of anticipated costs and benefits of the 
Federal mandate and an analysis of the extent to which such costs to 
State, local, and tribal governments may be paid with Federal financial 
assistance; (iii) if feasible, estimates of the future compliance costs 
and any disproportionate budgetary effects of the mandate; (iv) if 
feasible, estimates of the effect on the national economy; and (v) a 
description of the Agency's prior consultation with elected 
representatives of State, local, and tribal governments and a summary 
and evaluation of the comments and concerns presented. Section 203 
requires the Agency to establish a plan for obtaining input from and 
informing, educating, and advising any small governments that may be 
significantly or uniquely impacted by the rule.
    Under section 205 of the Unfunded Mandates Act, EPA must identify 
and consider a reasonable number of regulatory alternatives before 
promulgating a rule for which a budgetary impact statement must be 
prepared. The Agency must select from those alternatives the most cost-
effective and least burdensome alternative that achieves the objectives 
of the rule unless the Agency explains why this alternative is not 
selected or unless the selection of this alternative is inconsistent 
with law.
    Because this rule is not estimated to result in the expenditure by 
State, local, and tribal governments and the private sector, in 
aggregate, of over $100 million per year, EPA is not required under 
UMRA to develop a budgetary impact statement or to undertake the 
analysis under section 205. However, because certain options considered 
by EPA would have resulted in a total cost in excess of $100 million, 
EPA did prepare such statement and analysis and they are included as 
part of the Regulatory Impact Analysis, which is included in the 
docket.
    To the extent governmental entities are affected by the rule as 
permitting authorities, the costs of the rule are offset or mitigated 
by receipt of title V permit fees, since the rule affects only title V 
sources. Part 70 requires sources of pollution to pay permit fees 
sufficient to offset the costs incurred by the permitting authority in 
managing its operating permits program. Since part 64 introduces 
additional requirements for permitting authorities, these incremental 
costs must be incorporated into the operating permit fee. Because 
Permitting Authority costs may be transferred to sources of pollution 
through the permit fee, the administrative and recordkeeping cost of 
this rulemaking to State, local, and tribal governments is, for 
practical purposes, zero. EPA has also concluded that, to the extent 
small governments are impacted by this regulation because they are 
major stationary sources, the impact will not be significant. See 
Section III.E. As a result, UMRA requirements do not apply to this 
rulemaking.

[[Page 54939]]

D. Paperwork Reduction Act

    The information collection requirements in this rule have been 
submitted for approval to the Office of Management and Budget (OMB) 
under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. An 
Information Collection Request (ICR) document has been prepared by EPA 
(ICR No. 1663.02) and a copy may be obtained from Sandy Farmer, OPPE 
Regulatory Information Division; U.S. Environmental Protection Agency 
(2137); 401 M St., SW.; Washington, DC 20460 or by calling (202) 260-
2740. The information requirements are not effective until OMB approves 
them.
    The information is planned to be collected to fulfill requirements 
in both the title V operating permit program and part 64 programs. The 
operating permit program requires owners or operators of units that 
emit air pollutants to submit annual compliance certifications, to 
submit monitoring results at least semiannually, and to report 
deviations promptly. Part 64 requires monitoring for certain emissions 
units at major sources subject to the title V operating permits 
program. Therefore, the collection of information is mandated by the 
Act. Generally, emissions data cannot be considered confidential under 
the Act. However, to the extent allowable under the Act, the collection 
of information will be entitled to confidential treatment in accordance 
with EPA's procedures established in 40 CFR part 2.
    The part 64 rulemaking requires monitoring, compliance 
certification, periodic reporting, and recordkeeping information 
collections by owners and operators of title V sources with controlled 
pollutant-specific emissions units that have a pre-control potential to 
emit major amounts of regulated air pollutants. Owners or operators of 
affected emissions units will use the information as the basis for the 
compliance certification required by the operating permit program, and 
as the basis for compliance assurance monitoring reports. Sources may 
also use the information to determine and maintain the efficiency of 
process or emissions control devices. Permitting authorities will use 
the information to determining acceptability of proposed compliance 
assurance monitoring, to assess compliance, to input into reports to 
other agencies, and, when necessary, in enforcement proceedings and 
Quality Improvement Plans (QIPs). The information may be used by other 
entities, including federal entities and citizens. EPA will use the 
information to perform activities such as providing oversight and 
guidance to State and local agencies, and to assess requests for 
alternative monitoring.
    The implementation schedule for part 64 will phase-in 
implementation over a number of years, so that not all sources will 
have reporting and recordkeeping impacts in the first three years of 
implementation. The estimated annualized cost of CAM on a national 
level for the first three years of implementation is $7,891,000 (in 
1995 dollars). The annual average total capital and operation and 
maintenance costs are estimated at $1,230,000 (in 1995 dollars) for the 
first three years of implementation. The annual average burden hours 
for the first three years of implementation are estimated at 147,560. 
The Agency estimated the incremental reporting burden for this 
collection to average 1 hour annually per response, and to require 
between 26 and 390 hours annually for recordkeeping per response. This 
includes time for conducting activities over and above the requirements 
of part 70 such as an accounting of the number, duration and cause of 
monitor downtime incidents and exceedances, a reporting of corrective 
actions, and keeping records of data used to document the adequacy of 
monitoring. Note that the average burden hours and costs represent 
those estimated for the first three years of the rule's implementation 
during which a relatively small percentage of the affected pollutant-
specific emission units will be subject to part 64 requirements. More 
units will be affected per year in the six to eight years following the 
rule's publication and the reporting and recordkeeping burden will also 
increase. See the RIA for more discussion of the costs associated with 
years beyond the first three years.
    Burden means the total time, effort, or financial resources 
expended by persons to generate, maintain, retain, or disclose or 
provide information to or for a Federal agency. This includes the time 
needed to review instructions; develop, acquire, install, and utilize 
technology and systems for the purposes of collecting, validating, and 
verifying information, processing and maintaining information, and 
disclosing and providing information; adjust the existing ways to 
comply with any previously applicable instructions and requirements; 
train personnel to be able to respond to a collection of information; 
and transmit or otherwise disclose the information.
    An Agency may not conduct or sponsor, and a person is not required 
to respond to a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for EPA's 
regulations are listed in 40 CFR part 9 and 48 CFR Ch. 15.
    Send comments on the Agency's need for this information, the 
accuracy of the provided burden estimates, and any suggested methods 
for minimizing respondent burden, including through the use of 
automated collection techniques to the Director, OPPE Regulatory 
Information Division; U.S. Environmental Protection Agency (2137), 401 
M St., SW., Washington DC 20460; and to the Office of Information and 
Regulatory Affairs, Office of Management and Budget, 725 17th St., NW., 
Washington, DC 20503, marked ``Attention: Desk Officer for EPA.'' 
Comments are requested within November 21, 1997. Include the ICR number 
in any correspondence.

E. Regulatory Flexibility Act

    The Agency has determined that it is not necessary to prepare a 
regulatory flexibility analysis in connection with this rule. A 
screening analysis was prepared to examine the potential for 
significant adverse impacts on small entities associated with specific 
monitoring and certification provisions. For small governmental 
entities that may own or operate affected sources, EPA determined that 
the most likely small government and organization sources affected by 
the rule are municipal power plants and hospitals. After analysis, EPA 
determined that, given the relatively low numbers of impacted 
sources(140 small government utilities and 70 small organizations 
(hospitals)), the low percentage of impacted sources out of the total 
number of similar sources (11--18 percent of small government utilities 
and 3 percent of hospitals), and the low cost impacts associated with 
CAM (assumed similar to the cost impact on small business as discussed 
below), there will not be a significant impact upon a substantial 
number of small governments and organizations. See Section V of the 
Regulatory Impact Analysis included in the docket. Nevertheless, in 
developing the rule, EPA did provide numerous opportunities for 
consultation with interested parties, including State, local, and 
tribal governments, at public conferences and meetings. The EPA 
evaluated the comments and concerns expressed, and the rule reflects, 
to the extent consistent with the Act, those comments and concerns. 
Most importantly, the Agency received comments from approximately 80 
representatives of municipally-owned electric utilities that suggested 
exemptions for small municipal utility

[[Page 54940]]

units. In response, the rule includes an exemption for certain 
municipally-owned electric utility units that could be affected by the 
rule. These procedures ensured State and local governments an 
opportunity to give meaningful and timely input and obtain information, 
education and advice on compliance.
    EPA estimates 4,957 small firms nationwide could be affected by 
CAM. A total of 40 affected small firms within this group could have a 
potential impact over one percent of average annual revenues. The ratio 
is 0.0087, or less than one percent, which represents the percent of 
small affected firms that may experience greater than a 1 percent (but 
less than a 3 percent) increase in costs due to CAM. EPA believes that 
these estimates of the number of firms affected and the level of cost 
impact are overstated due to several conservative assumptions in the 
analysis. These assumptions are described in Chapter 5 of the 
Regulatory Impact Analysis. Given the conservativeness of this 
assessment and the fact that 99 percent of the affected small 
businesses are expected to have impacts of less than 1 percent and no 
small business is likely to experience costs exceeding 3 percent, the 
EPA concludes that CAM will not have a significant economic impact on a 
substantial number of small businesses. In addition, EPA also notes 
that the use of general permits under title V and assistance through 
the small business assistance program provisions of title V will assist 
in reducing the impacts of the part 64 requirements on small 
businesses.
    Accordingly, considering all of the above information, EPA 
concludes that this rule will not have a significant economic impact on 
a substantial number of small entities.

F. Submission to Congress and the General Accounting Office

    Under 5 U.S.C. 801(a)(1)(A) as added by the Small Business 
Regulatory Enforcement Fairness Act of 1996, EPA submitted a report 
containing this rule and other required information to the U.S. Senate, 
the U.S. House of Representatives, and the Comptroller General of the 
General Accounting Office prior to publication of the rule in today's 
Federal Register. This rule is not a ``major rule'' as defined by 
U.S.C. 804(2).

List of Subjects

40 CFR Part 64

    Environmental protection, Air pollution control, Monitoring, 
Operating permits, Reporting and recordkeeping requirements.

40 CFR Part 70

    Air pollution control, Monitoring, Operating permits, Reporting and 
recordkeeping requirements.

40 CFR Part 71

    Air pollution control, Monitoring, Operating permits, Reporting and 
recordkeeping requirements.

    Dated: October 3, 1997.
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 follows:
    1. Part 64 is added to read as follows:

PART 64--COMPLIANCE ASSURANCE MONITORING

Sec.
64.1  Definitions.
64.2  Applicability.
64.3  Monitoring design criteria.
64.4  Submittal requirements.
64.5  Deadlines for submittals.
64.6  Approval of monitoring.
64.7  Operation of approved monitoring.
64.8  Quality improvement plan (QIP) requirements.
64.9  Reporting and recordkeeping requirements.
64.10  Savings provisions.

    Authority: 42 U.S.C. 7414 and 7661-7661f.


Sec. 64.1  Definitions.

    The following definitions apply to this part. Except as 
specifically provided in this section, terms used in this part retain 
the meaning accorded them under the applicable provisions of the Act.
    Act means the Clean Air Act, as amended by Pub.L. 101-549, 42 
U.S.C. 7401, et seq.
    Applicable requirement shall have the same meaning as provided 
under part 70 of this chapter.
    Capture system means the equipment (including but not limited to 
hoods, ducts, fans, and booths) used to contain, capture and transport 
a pollutant to a control device.
    Continuous compliance determination method means a method, 
specified by the applicable standard or an applicable permit condition, 
which:
    (1) Is used to determine compliance with an emission limitation or 
standard on a continuous basis, consistent with the averaging period 
established for the emission limitation or standard; and
    (2) Provides data either in units of the standard or correlated 
directly with the compliance limit.
    Control device means equipment, other than inherent process 
equipment, that is used to destroy or remove air pollutant(s) prior to 
discharge to the atmosphere. The types of equipment that may commonly 
be used as control devices include, but are not limited to, fabric 
filters, mechanical collectors, electrostatic precipitators, inertial 
separators, afterburners, thermal or catalytic incinerators, adsorption 
devices (such as carbon beds), condensers, scrubbers (such as wet 
collection and gas absorption devices), selective catalytic or non-
catalytic reduction systems, flue gas recirculation systems, spray 
dryers, spray towers, mist eliminators, acid plants, sulfur recovery 
plants, injection systems (such as water, steam, ammonia, sorbent or 
limestone injection), and combustion devices independent of the 
particular process being conducted at an emissions unit (e.g., the 
destruction of emissions achieved by venting process emission streams 
to flares, boilers or process heaters). For purposes of this part, a 
control device does not include passive control measures that act to 
prevent pollutants from forming, such as the use of seals, lids, or 
roofs to prevent the release of pollutants, use of low-polluting fuel 
or feedstocks, or the use of combustion or other process design 
features or characteristics. If an applicable requirement establishes 
that particular equipment which otherwise meets this definition of a 
control device does not constitute a control device as applied to a 
particular pollutant-specific emissions unit, then that definition 
shall be binding for purposes of this part.
    Data means the results of any type of monitoring or method, 
including the results of instrumental or non-instrumental monitoring, 
emission calculations, manual sampling procedures, recordkeeping 
procedures, or any other form of information collection procedure used 
in connection with any type of monitoring or method.
    Emission limitation or standard means any applicable requirement 
that constitutes an emission limitation, emission standard, standard of 
performance or means of emission limitation as defined under the Act. 
An emission limitation or standard may be expressed in terms of the 
pollutant, expressed either as a specific quantity, rate or 
concentration of emissions (e.g., pounds of SO<INF>2</INF> per hour, 
pounds of SO<INF>2</INF> per million British thermal units of fuel 
input, kilograms of VOC per liter of applied coating solids, or parts 
per million by volume of SO<INF>2</INF>) or as the relationship of 
uncontrolled to controlled emissions (e.g., percentage capture and 
destruction efficiency of VOC or percentage reduction of 
SO<INF>2</INF>).

[[Page 54941]]

An emission limitation or standard may also be expressed either as a 
work practice, process or control device parameter, or other form of 
specific design, equipment, operational, or operation and maintenance 
requirement. For purposes of this part, an emission limitation or 
standard shall not include general operation requirements that an owner 
or operator may be required to meet, such as requirements to obtain a 
permit, to operate and maintain sources in accordance with good air 
pollution control practices, to develop and maintain a malfunction 
abatement plan, to keep records, submit reports, or conduct monitoring.
    Emissions unit shall have the same meaning as provided under part 
70 of this chapter.
    Exceedance shall mean a condition that is detected by monitoring 
that provides data in terms of an emission limitation or standard and 
that indicates that emissions (or opacity) are greater than the 
applicable emission limitation or standard (or less than the applicable 
standard in the case of a percent reduction requirement) consistent 
with any averaging period specified for averaging the results of the 
monitoring.
    Excursion shall mean a departure from an indicator range 
established for monitoring under this part, consistent with any 
averaging period specified for averaging the results of the monitoring.
    Inherent process equipment means equipment that is necessary for 
the proper or safe functioning of the process, or material recovery 
equipment that the owner or operator documents is installed and 
operated primarily for purposes other than compliance with air 
pollution regulations. Equipment that must be operated at an efficiency 
higher than that achieved during normal process operations in order to 
comply with the applicable emission limitation or standard is not 
inherent process equipment. For the purposes of this part, inherent 
process equipment is not considered a control device.
    Major source shall have the same meaning as provided under part 70 
or 71 of this chapter.
    Monitoring means any form of collecting data on a routine basis to 
determine or otherwise assess compliance with emission limitations or 
standards. Recordkeeping may be considered monitoring where such 
records are used to determine or assess compliance with an emission 
limitation or standard (such as records of raw material content and 
usage, or records documenting compliance with work practice 
requirements). The conduct of compliance method tests, such as the 
procedures in appendix A to part 60 of this chapter, on a routine 
periodic basis may be considered monitoring (or as a supplement to 
other monitoring), provided that requirements to conduct such tests on 
a one-time basis or at such times as a regulatory authority may require 
on a non-regular basis are not considered monitoring requirements for 
purposes of this paragraph. Monitoring may include one or more than one 
of the following data collection techniques, where appropriate for a 
particular circumstance:
    (1) Continuous emission or opacity monitoring systems.
    (2) Continuous process, capture system, control device or other 
relevant parameter monitoring systems or procedures, including a 
predictive emission monitoring system.
    (3) Emission estimation and calculation procedures (e.g., mass 
balance or stoichiometric calculations).
    (4) Maintenance and analysis of records of fuel or raw materials 
usage.
    (5) Recording results of a program or protocol to conduct specific 
operation and maintenance procedures.
    (6) Verification of emissions, process parameters, capture system 
parameters, or control device parameters using portable or in situ 
measurement devices.
    (7) Visible emission observations.
    (8) Any other form of measuring, recording, or verifying on a 
routine basis emissions, process parameters, capture system parameters, 
control device parameters or other factors relevant to assessing 
compliance with emission limitations or standards.
    Owner or operator means any person who owns, leases, operates, 
controls or supervises a stationary source subject to this part.
    Part 70 or 71 permit shall have the same meaning as provided under 
part 70 or 71 of this chapter, provided that it shall also refer to a 
permit issued, renewed, amended, revised, or modified under any federal 
permit program promulgated under title V of the Act.
    Part 70 or 71 permit application shall mean an application 
(including any supplement to a previously submitted application) that 
is submitted by the owner or operator in order to obtain a part 70 or 
71 permit.
    Permitting authority shall have the same meaning as provided under 
part 70 or 71 of this chapter.
    Pollutant-specific emissions unit means an emissions unit 
considered separately with respect to each regulated air pollutant.
    Potential to emit shall have the same meaning as provided under 
part 70 or 71 of this chapter, provided that it shall be applied with 
respect to an ``emissions unit'' as defined under this part in addition 
to a ``stationary source'' as provided under part 70 or 71 of this 
chapter.
    Predictive emission monitoring system (PEMS) means a system that 
uses process and other parameters as inputs to a computer program or 
other data reduction system to produce values in terms of the 
applicable emission limitation or standard.
    Regulated air pollutant shall have the same meaning as provided 
under part 70 or 71 of this chapter.


Sec. 64.2  Applicability.

    (a) General applicability. Except for backup utility units that are 
exempt under paragraph (b)(2) of this section, the requirements of this 
part shall apply to a pollutant-specific emissions unit at a major 
source that is required to obtain a part 70 or 71 permit if the unit 
satisfies all of the following criteria:
    (1) The unit is subject to an emission limitation or standard for 
the applicable regulated air pollutant (or a surrogate thereof), other 
than an emission limitation or standard that is exempt under paragraph 
(b)(1) of this section;
    (2) The unit uses a control device to achieve compliance with any 
such emission limitation or standard; and
    (3) The unit has potential pre-control device emissions of the 
applicable regulated air pollutant that are equal to or greater than 
100 percent of the amount, in tons per year, required for a source to 
be classified as a major source. For purposes of this paragraph, 
``potential pre-control device emissions'' shall have the same meaning 
as ``potential to emit,'' as defined in Sec. 64.1, except that emission 
reductions achieved by the applicable control device shall not be taken 
into account.
    (b) Exemptions--. (1) Exempt emission limitations or standards. The 
requirements of this part shall not apply to any of the following 
emission limitations or standards:
    (i) Emission limitations or standards proposed by the Administrator 
after November 15, 1990 pursuant to section 111 or 112 of the Act.
    (ii) Stratospheric ozone protection requirements under title VI of 
the Act.
    (iii) Acid Rain Program requirements pursuant to sections 404, 405, 
406, 407(a), 407(b), or 410 of the Act.
    (iv) Emission limitations or standards or other applicable 
requirements that apply solely under an emissions trading program 
approved or promulgated by the Administrator under the Act that allows 
for trading emissions within a source or between sources.

[[Page 54942]]

    (v) An emissions cap that meets the requirements specified in 
Sec. 70.4(b)(12) or Sec. 71.6(a)(13)(iii) of this chapter.
    (vi) Emission limitations or standards for which a part 70 or 71 
permit specifies a continuous compliance determination method, as 
defined in Sec. 64.1. The exemption provided in this paragraph 
(b)(1)(vi) shall not apply if the applicable compliance method includes 
an assumed control device emission reduction factor that could be 
affected by the actual operation and maintenance of the control device 
(such as a surface coating line controlled by an incinerator for which 
continuous compliance is determined by calculating emissions on the 
basis of coating records and an assumed control device efficiency 
factor based on an initial performance test; in this example, this part 
would apply to the control device and capture system, but not to the 
remaining elements of the coating line, such as raw material usage).
    (2) Exemption for backup utility power emissions units. The 
requirements of this part shall not apply to a utility unit, as defined 
in Sec. 72.2 of this chapter, that is municipally-owned if the owner or 
operator provides documentation in a part 70 or 71 permit application 
that:
    (i) The utility unit is exempt from all monitoring requirements in 
part 75 (including the appendices thereto) of this chapter;
    (ii) The utility unit is operated for the sole purpose of providing 
electricity during periods of peak electrical demand or emergency 
situations and will be operated consistent with that purpose throughout 
the part 70 or 71 permit term. The owner or operator shall provide 
historical operating data and relevant contractual obligations to 
document that this criterion is satisfied; and
    (iii) The actual emissions from the utility unit, based on the 
average annual emissions over the last three calendar years of 
operation (or such shorter time period that is available for units with 
fewer than three years of operation) are less than 50 percent of the 
amount in tons per year required for a source to be classified as a 
major source and are expected to remain so.


Sec. 64.3  Monitoring design criteria.

    (a) General criteria. To provide a reasonable assurance of 
compliance with emission limitations or standards for the anticipated 
range of operations at a pollutant-specific emissions unit, monitoring 
under this part shall meet the following general criteria:
    (1) The owner or operator shall design the monitoring to obtain 
data for one or more indicators of emission control performance for the 
control device, any associated capture system and, if necessary to 
satisfy paragraph (a)(2) of this section, processes at a pollutant-
specific emissions unit. Indicators of performance may include, but are 
not limited to, direct or predicted emissions (including visible 
emissions or opacity), process and control device parameters that 
affect control device (and capture system) efficiency or emission 
rates, or recorded findings of inspection and maintenance activities 
conducted by the owner or operator.
    (2) The owner or operator shall establish an appropriate range(s) 
or designated condition(s) for the selected indicator(s) such that 
operation within the ranges provides a reasonable assurance of ongoing 
compliance with emission limitations or standards for the anticipated 
range of operating conditions. Such range(s) or condition(s) shall 
reflect the proper operation and maintenance of the control device (and 
associated capture system), in accordance with applicable design 
properties, for minimizing emissions over the anticipated range of 
operating conditions at least to the level required to achieve 
compliance with the applicable requirements. The reasonable assurance 
of compliance will be assessed by maintaining performance within the 
indicator range(s) or designated condition(s). The ranges shall be 
established in accordance with the design and performance requirements 
in this section and documented in accordance with the requirements in 
Sec. 64.4. If necessary to assure that the control device and 
associated capture system can satisfy this criterion, the owner or 
operator shall monitor appropriate process operational parameters (such 
as total throughput where necessary to stay within the rated capacity 
for a control device). In addition, unless specifically stated 
otherwise by an applicable requirement, the owner or operator shall 
monitor indicators to detect any bypass of the control device (or 
capture system) to the atmosphere, if such bypass can occur based on 
the design of the pollutant-specific emissions unit.
    (3) The design of indicator ranges or designated conditions may be:
    (i) Based on a single maximum or minimum value if appropriate 
(e.g., maintaining condenser temperatures a certain number of degrees 
below the condensation temperature of the applicable compound(s) being 
processed) or at multiple levels that are relevant to distinctly 
different operating conditions (e.g., high versus low load levels).
    (ii) Expressed as a function of process variables (e.g., an 
indicator range expressed as minimum to maximum pressure drop across a 
venturi throat in a particulate control scrubber).
    (iii) Expressed as maintaining the applicable parameter in a 
particular operational status or designated condition (e.g., position 
of a damper controlling gas flow to the atmosphere through a by-pass 
duct).
    (iv) Established as interdependent between more than one indicator.
    (b) Performance criteria. The owner or operator shall design the 
monitoring to meet the following performance criteria:
    (1) Specifications that provide for obtaining data that are 
representative of the emissions or parameters being monitored (such as 
detector location and installation specifications, if applicable).
    (2) For new or modified monitoring equipment, verification 
procedures to confirm the operational status of the monitoring prior to 
the date by which the owner or operator must conduct monitoring under 
this part as specified in Sec. 64.7(a). The owner or operator shall 
consider the monitoring equipment manufacturer's requirements or 
recommendations for installation, calibration, and start-up operation.
    (3) Quality assurance and control practices that are adequate to 
ensure the continuing validity of the data. The owner or operator shall 
consider manufacturer recommendations or requirements applicable to the 
monitoring in developing appropriate quality assurance and control 
practices.
    (4) Specifications for the frequency of conducting the monitoring, 
the data collection procedures that will be used (e.g., computerized 
data acquisition and handling, alarm sensor, or manual log entries 
based on gauge readings), and, if applicable, the period over which 
discrete data points will be averaged for the purpose of determining 
whether an excursion or exceedance has occurred.
    (i) At a minimum, the owner or operator shall design the period 
over which data are obtained and, if applicable, averaged consistent 
with the characteristics and typical variability of the pollutant-
specific emissions unit (including the control device and associated 
capture system). Such intervals shall be commensurate with the time 
period over which a change in control device performance that would 
require actions by owner or operator to return operations within normal 
ranges or designated conditions is likely to be observed.
    (ii) For all pollutant-specific emissions units with the potential 
to emit, calculated including the effect of

[[Page 54943]]

control devices, the applicable regulated air pollutant in an amount 
equal to or greater than 100 percent of the amount, in tons per year, 
required for a source to be classified as a major source, for each 
parameter monitored, the owner or operator shall collect four or more 
data values equally spaced over each hour and average the values, as 
applicable, over the applicable averaging period as determined in 
accordance with paragraph (b)(4)(i) of this section. The permitting 
authority may approve a reduced data collection frequency, if 
appropriate, based on information presented by the owner or operator 
concerning the data collection mechanisms available for a particular 
parameter for the particular pollutant-specific emissions unit (e.g., 
integrated raw material or fuel analysis data, noninstrumental 
measurement of waste feed rate or visible emissions, use of a portable 
analyzer or an alarm sensor).
    (iii) For other pollutant-specific emissions units, the frequency 
of data collection may be less than the frequency specified in 
paragraph (b)(4)(ii) of this section but the monitoring shall include 
some data collection at least once per 24-hour period (e.g., a daily 
inspection of a carbon adsorber operation in conjunction with a weekly 
or monthly check of emissions with a portable analyzer).
    (c) Evaluation factors. In designing monitoring to meet the 
requirements in paragraphs (a) and (b) of this section, the owner or 
operator shall take into account site-specific factors including the 
applicability of existing monitoring equipment and procedures, the 
ability of the monitoring to account for process and control device 
operational variability, the reliability and latitude built into the 
control technology, and the level of actual emissions relative to the 
compliance limitation.
    (d) Special criteria for the use of continuous emission, opacity or 
predictive monitoring systems. (1) If a continuous emission monitoring 
system (CEMS), continuous opacity monitoring system (COMS) or 
predictive emission monitoring system (PEMS) is required pursuant to 
other authority under the Act or state or local law, the owner or 
operator shall use such system to satisfy the requirements of this 
part.
    (2) The use of a CEMS, COMS, or PEMS that satisfies any of the 
following monitoring requirements shall be deemed to satisfy the 
general design criteria in paragraphs (a) and (b) of this section, 
provided that a COMS may be subject to the criteria for establishing 
indicator ranges under paragraph (a) of this section:
    (i) Section 51.214 and appendix P of part 51 of this chapter;
    (ii) Section 60.13 and appendix B of part 60 of this chapter;
    (iii) Section 63.8 and any applicable performance specifications 
required pursuant to the applicable subpart of part 63 of this chapter;
    (iv) Part 75 of this chapter;
    (v) Subpart H and appendix IX of part 266 of this chapter; or
    (vi) If an applicable requirement does not otherwise require 
compliance with the requirements listed in the preceding paragraphs 
(d)(2)(i) through (v) of this section, comparable requirements and 
specifications established by the permitting authority.
    (3) The owner or operator shall design the monitoring system 
subject to this paragraph (d) to:
    (i) Allow for reporting of exceedances (or excursions if applicable 
to a COMS used to assure compliance with a particulate matter 
standard), consistent with any period for reporting of exceedances in 
an underlying requirement. If an underlying requirement does not 
contain a provision for establishing an averaging period for the 
reporting of exceedances or excursions, the criteria used to develop an 
averaging period in (b)(4) of this section shall apply; and
    (ii) Provide an indicator range consistent with paragraph (a) of 
this section for a COMS used to assure compliance with a particulate 
matter standard. If an opacity standard applies to the pollutant-
specific emissions unit, such limit may be used as the appropriate 
indicator range unless the opacity limit fails to meet the criteria in 
paragraph (a) of this section after considering the type of control 
device and other site-specific factors applicable to the pollutant-
specific emissions unit.


Sec. 64.4  Submittal requirements.

    (a) The owner or operator shall submit to the permitting authority 
monitoring that satisfies the design requirements in Sec. 64.3. The 
submission shall include the following information:
    (1) The indicators to be monitored to satisfy Secs. 64.3(a)(1)-(2);
    (2) The ranges or designated conditions for such indicators, or the 
process by which such indicator ranges or designated conditions shall 
be established;
    (3) The performance criteria for the monitoring to satisfy 
Sec. 64.3(b); and
    (4) If applicable, the indicator ranges and performance criteria 
for a CEMS, COMS or PEMS pursuant to Sec. 64.3(d).
    (b) As part of the information submitted, the owner or operator 
shall submit a justification for the proposed elements of the 
monitoring. If the performance specifications proposed to satisfy 
Sec. 64.3(b)(2) or (3) include differences from manufacturer 
recommendations, the owner or operator shall explain the reasons for 
the differences between the requirements proposed by the owner or 
operator and the manufacturer's recommendations or requirements. The 
owner or operator also shall submit any data supporting the 
justification, and may refer to generally available sources of 
information used to support the justification (such as generally 
available air pollution engineering manuals, or EPA or permitting 
authority publications on appropriate monitoring for various types of 
control devices or capture systems). To justify the appropriateness of 
the monitoring elements proposed, the owner or operator may rely in 
part on existing applicable requirements that establish the monitoring 
for the applicable pollutant-specific emissions unit or a similar unit. 
If an owner or operator relies on presumptively acceptable monitoring, 
no further justification for the appropriateness of that monitoring 
should be necessary other than an explanation of the applicability of 
such monitoring to the unit in question, unless data or information is 
brought forward to rebut the assumption. Presumptively acceptable 
monitoring includes:
    (1) Presumptively acceptable or required monitoring approaches, 
established by the permitting authority in a rule that constitutes part 
of the applicable implementation plan required pursuant to title I of 
the Act, that are designed to achieve compliance with this part for 
particular pollutant-specific emissions units;
    (2) Continuous emission, opacity or predictive emission monitoring 
systems that satisfy applicable monitoring requirements and performance 
specifications as specified in Sec. 64.3(d);
    (3) Excepted or alternative monitoring methods allowed or approved 
pursuant to part 75 of this chapter;
    (4) Monitoring included for standards exempt from this part 
pursuant to Sec. 64.2(b)(1)(i) or (vi) to the extent such monitoring is 
applicable to the performance of the control device (and associated 
capture system) for the pollutant-specific emissions unit; and
    (5) Presumptively acceptable monitoring identified in guidance by 
EPA. Such guidance will address the requirements under Secs. 64.4(a), 
(b), and (c) to the extent practicable.
    (c)(1) Except as provided in paragraph (d) of this section, the 
owner or operator shall submit control device (and process

[[Page 54944]]

and capture system, if applicable) operating parameter data obtained 
during the conduct of the applicable compliance or performance test 
conducted under conditions specified by the applicable rule. If the 
applicable rule does not specify testing conditions or only partially 
specifies test conditions, the performance test generally shall be 
conducted under conditions representative of maximum emissions 
potential under anticipated operating conditions at the pollutant-
specific emissions unit. Such data may be supplemented, if desired, by 
engineering assessments and manufacturer's recommendations to justify 
the indicator ranges (or, if applicable, the procedures for 
establishing such indicator ranges). Emission testing is not required 
to be conducted over the entire indicator range or range of potential 
emissions.
    (2) The owner or operator must document that no changes to the 
pollutant-specific emissions unit, including the control device and 
capture system, have taken place that could result in a significant 
change in the control system performance or the selected ranges or 
designated conditions for the indicators to be monitored since the 
performance or compliance tests were conducted.
    (d) If existing data from unit-specific compliance or performance 
testing specified in paragraph (c) of this section are not available, 
the owner or operator:
    (1) Shall submit a test plan and schedule for obtaining such data 
in accordance with paragraph (e) of this section; or
    (2) May submit indicator ranges (or procedures for establishing 
indicator ranges) that rely on engineering assessments and other data, 
provided that the owner or operator demonstrates that factors specific 
to the type of monitoring, control device, or pollutant-specific 
emissions unit make compliance or performance testing unnecessary to 
establish indicator ranges at levels that satisfy the criteria in 
Sec. 64.3(a).
    (e) If the monitoring submitted by the owner or operator requires 
installation, testing, or other necessary activities prior to use of 
the monitoring for purposes of this part, the owner or operator shall 
include an implementation plan and schedule for installing, testing and 
performing any other appropriate activities prior to use of the 
monitoring. The implementation plan and schedule shall provide for use 
of the monitoring as expeditiously as practicable after approval of the 
monitoring in the part 70 or 71 permit pursuant to Sec. 64.6, but in no 
case shall the schedule for completing installation and beginning 
operation of the monitoring exceed 180 days after approval of the 
permit.
    (f) If a control device is common to more than one pollutant-
specific emissions unit, the owner or operator may submit monitoring 
for the control device and identify the pollutant-specific emissions 
units affected and any process or associated capture device conditions 
that must be maintained or monitored in accordance with Sec. 64.3(a) 
rather than submit separate monitoring for each pollutant-specific 
emissions unit.
    (g) If a single pollutant-specific emissions unit is controlled by 
more than one control device similar in design and operation, the owner 
or operator may submit monitoring that applies to all the control 
devices and identify the control devices affected and any process or 
associated capture device conditions that must be maintained or 
monitored in accordance with Sec. 64.3(a) rather than submit a separate 
description of monitoring for each control device.


Sec. 64.5  Deadlines for submittals.

    (a) Large pollutant-specific emissions units. For all pollutant-
specific emissions units with the potential to emit (taking into 
account control devices to the extent appropriate under the definition 
of this term in Sec. 64.1) the applicable regulated air pollutant in an 
amount equal to or greater than 100 percent of the amount, in tons per 
year, required for a source to be classified as a major source, the 
owner or operator shall submit the information required under Sec. 64.4 
at the following times:
    (1) On or after April 20, 1998, the owner or operator shall submit 
information as part of an application for an initial part 70 or 71 
permit if, by that date, the application either:
    (i) Has not been filed; or
    (ii) Has not yet been determined to be complete by the permitting 
authority.
    (2) On or after April 20, 1998, the owner or operator shall submit 
information as part of an application for a significant permit revision 
under part 70 or 71 of this chapter, but only with respect to those 
pollutant-specific emissions units for which the proposed permit 
revision is applicable.
    (3) The owner or operator shall submit any information not 
submitted under the deadlines set forth in paragraphs (a)(1) and (2) of 
this section as part of the application for the renewal of a part 70 or 
71 permit.
    (b) Other pollutant-specific emissions units. For all other 
pollutant-specific emissions units subject to this part and not subject 
to Sec. 64.5(a), the owner or operator shall submit the information 
required under Sec. 64.4 as part of an application for a renewal of a 
part 70 or 71 permit.
    (c) The effective date for the requirement to submit information 
under Sec. 64.4 shall be as specified pursuant to paragraphs (a)-(b) of 
this section and a permit reopening to require the submittal of 
information under this section shall not be required pursuant to 
Sec. 70.7(f)(1)(i) of this chapter, provided, however, that, if a part 
70 or 71 permit is reopened for cause by EPA or the permitting 
authority pursuant to Sec. 70.7(f)(1)(iii) or (iv), or Sec. 71.7(f) or 
(g), the applicable agency may require the submittal of information 
under this section for those pollutant-specific emissions units that 
are subject to this part and that are affected by the permit reopening.
    (d) Prior to approval of monitoring that satisfies this part, the 
owner or operator is subject to the requirements of 
Sec. 70.6(a)(3)(i)(B).


Sec. 64.6  Approval of monitoring.

    (a) Based on an application that includes the information submitted 
in accordance with Sec. 64.5, the permitting authority shall act to 
approve the monitoring submitted by the owner or operator by confirming 
that the monitoring satisfies the requirements in Sec. 64.3.
    (b) In approving monitoring under this section, the permitting 
authority may condition the approval on the owner or operator 
collecting additional data on the indicators to be monitored for a 
pollutant-specific emissions unit, including required compliance or 
performance testing, to confirm the ability of the monitoring to 
provide data that are sufficient to satisfy the requirements of this 
part and to confirm the appropriateness of an indicator range(s) or 
designated condition(s) proposed to satisfy Sec. 64.3(a)(2) and (3) and 
consistent with the schedule in Sec. 64.4(e).
    (c) If the permitting authority approves the proposed monitoring, 
the permitting authority shall establish one or more permit terms or 
conditions that specify the required monitoring in accordance with 
Sec. 70.6(a)(3)(i) of this chapter. At a minimum, the permit shall 
specify:
    (1) The approved monitoring approach that includes all of the 
following:
    (i) The indicator(s) to be monitored (such as temperature, pressure 
drop, emissions, or similar parameter);
    (ii) The means or device to be used to measure the indicator(s) 
(such as

[[Page 54945]]

temperature measurement device, visual observation, or CEMS); and
    (iii) The performance requirements established to satisfy 
Sec. 64.3(b) or (d), as applicable.
    (2) The means by which the owner or operator will define an 
exceedance or excursion for purposes of responding to and reporting 
exceedances or excursions under Secs. 64.7 and 64.8 of this part. The 
permit shall specify the level at which an excursion or exceedance will 
be deemed to occur, including the appropriate averaging period 
associated with such exceedance or excursion. For defining an excursion 
from an indicator range or designated condition, the permit may either 
include the specific value(s) or condition(s) at which an excursion 
shall occur, or the specific procedures that will be used to establish 
that value or condition. If the latter, the permit shall specify 
appropriate notice procedures for the owner or operator to notify the 
permitting authority upon any establishment or reestablishment of the 
value.
    (3) The obligation to conduct the monitoring and fulfill the other 
obligations specified in Secs. 64.7 through 64.9 of this part.
    (4) If appropriate, a minimum data availability requirement for 
valid data collection for each averaging period, and, if appropriate, a 
minimum data availability requirement for the averaging periods in a 
reporting period.
    (d) If the monitoring proposed by the owner or operator requires 
installation, testing or final verification of operational status, the 
part 70 or 71 permit shall include an enforceable schedule with 
appropriate milestones for completing such installation, testing, or 
final verification consistent with the requirements in Sec. 64.4(e).
    (e) If the permitting authority disapproves the proposed 
monitoring, the following applies:
    (1) The draft or final permit shall include, at a minimum, 
monitoring that satisfies the requirements of Sec. 70.6(a)(3)(i)(B);
    (2) The permitting authority shall include in the draft or final 
permit a compliance schedule for the source owner to submit monitoring 
that satisfies Secs. 64.3 and 64.4, but in no case shall the owner or 
operator submit revised monitoring more than 180 days from the date of 
issuance of the draft or final permit; and
    (3) If the source owner or operator does not submit the monitoring 
in accordance with the compliance schedule as required in paragraph 
(e)(2) of this section or if the permitting authority disapproves the 
monitoring submitted, the source owner or operator shall be deemed not 
in compliance with part 64, unless the source owner or operator 
successfully challenges the disapproval.


Sec. 64.7  Operation of approved monitoring.

    (a) Commencement of operation. The owner or operator shall conduct 
the monitoring required under this part upon issuance of a part 70 or 
71 permit that includes such monitoring, or by such later date 
specified in the permit pursuant to Sec. 64.6(d).
    (b) Proper maintenance. At all times, the owner or operator shall 
maintain the monitoring, including but not limited to, maintaining 
necessary parts for routine repairs of the monitoring equipment.
    (c) Continued operation. Except for, as applicable, monitoring 
malfunctions, associated repairs, and required quality assurance or 
control activities (including, as applicable, calibration checks and 
required zero and span adjustments), the owner or operator shall 
conduct all monitoring in continuous operation (or shall collect data 
at all required intervals) at all times that the pollutant-specific 
emissions unit is operating. Data recorded during monitoring 
malfunctions, associated repairs, and required quality assurance or 
control activities shall not be used for purposes of this part, 
including data averages and calculations, or fulfilling a minimum data 
availability requirement, if applicable. The owner or operator shall 
use all the data collected during all other periods in assessing the 
operation of the control device and associated control system. A 
monitoring malfunction is any sudden, infrequent, not reasonably 
preventable failure of the monitoring to provide valid data. Monitoring 
failures that are caused in part by poor maintenance or careless 
operation are not malfunctions.
    (d) Response to excursions or exceedances. (1) Upon detecting an 
excursion or exceedance, the owner or operator shall restore operation 
of the pollutant-specific emissions unit (including the control device 
and associated capture system) to its normal or usual manner of 
operation as expeditiously as practicable in accordance with good air 
pollution control practices for minimizing emissions. The response 
shall include minimizing the period of any startup, shutdown or 
malfunction and taking any necessary corrective actions to restore 
normal operation and prevent the likely recurrence of the cause of an 
excursion or exceedance (other than those caused by excused startup or 
shutdown conditions). Such actions may include initial inspection and 
evaluation, recording that operations returned to normal without 
operator action (such as through response by a computerized 
distribution control system), or any necessary follow-up actions to 
return operation to within the indicator range, designated condition, 
or below the applicable emission limitation or standard, as applicable.
    (2) Determination of whether the owner or operator has used 
acceptable procedures in response to an excursion or exceedance will be 
based on information available, which may include but is not limited 
to, monitoring results, review of operation and maintenance procedures 
and records, and inspection of the control device, associated capture 
system, and the process.
    (e) Documentation of need for improved monitoring. After approval 
of monitoring under this part, if the owner or operator identifies a 
failure to achieve compliance with an emission limitation or standard 
for which the approved monitoring did not provide an indication of an 
excursion or exceedance while providing valid data, or the results of 
compliance or performance testing document a need to modify the 
existing indicator ranges or designated conditions, the owner or 
operator shall promptly notify the permitting authority and, if 
necessary, submit a proposed modification to the part 70 or 71 permit 
to address the necessary monitoring changes. Such a modification may 
include, but is not limited to, reestablishing indicator ranges or 
designated conditions, modifying the frequency of conducting monitoring 
and collecting data, or the monitoring of additional parameters.


Sec. 64.8  Quality improvement plan (QIP) requirements.

    (a) Based on the results of a determination made under 
Sec. 64.7(d)(2), the Administrator or the permitting authority may 
require the owner or operator to develop and implement a QIP. 
Consistent with Sec. 64.6(c)(3), the part 70 or 71 permit may specify 
an appropriate threshold, such as an accumulation of exceedances or 
excursions exceeding 5 percent duration of a pollutant-specific 
emissions unit's operating time for a reporting period, for requiring 
the implementation of a QIP. The threshold may be set at a higher or 
lower percent or may rely on other criteria for purposes of indicating 
whether a pollutant-specific emissions unit is being maintained and 
operated in a manner consistent with good air pollution control 
practices.
    (b) Elements of a QIP:

[[Page 54946]]

    (1) The owner or operator shall maintain a written QIP, if 
required, and have it available for inspection.
    (2) The plan initially shall include procedures for evaluating the 
control performance problems and, based on the results of the 
evaluation procedures, the owner or operator shall modify the plan to 
include procedures for conducting one or more of the following actions, 
as appropriate:
    (i) Improved preventive maintenance practices.
    (ii) Process operation changes.
    (iii) Appropriate improvements to control methods.
    (iv) Other steps appropriate to correct control performance.
    (v) More frequent or improved monitoring (only in conjunction with 
one or more steps under paragraphs (b)(2)(i) through (iv) of this 
section).
    (c) If a QIP is required, the owner or operator shall develop and 
implement a QIP as expeditiously as practicable and shall notify the 
permitting authority if the period for completing the improvements 
contained in the QIP exceeds 180 days from the date on which the need 
to implement the QIP was determined.
    (d) Following implementation of a QIP, upon any subsequent 
determination pursuant to Sec. 64.7(d)(2) the Administrator or the 
permitting authority may require that an owner or operator make 
reasonable changes to the QIP if the QIP is found to have:
    (1) Failed to address the cause of the control device performance 
problems; or
    (2) Failed to provide adequate procedures for correcting control 
device performance problems as expeditiously as practicable in 
accordance with good air pollution control practices for minimizing 
emissions.
    (e) Implementation of a QIP shall not excuse the owner or operator 
of a source from compliance with any existing emission limitation or 
standard, or any existing monitoring, testing, reporting or 
recordkeeping requirement that may apply under federal, state, or local 
law, or any other applicable requirements under the Act.


Sec. 64.9  Reporting and recordkeeping requirements.

    (a) General reporting requirements. (1) On and after the date 
specified in Sec. 64.7(a) by which the owner or operator must use 
monitoring that meets the requirements of this part, the owner or 
operator shall submit monitoring reports to the permitting authority in 
accordance with Sec. 70.6(a)(3)(iii) of this chapter.
    (2) A report for monitoring under this part shall include, at a 
minimum, the information required under Sec. 70.6(a)(3)(iii) of this 
chapter and the following information, as applicable:
    (i) Summary information on the number, duration and cause 
(including unknown cause, if applicable) of excursions or exceedances, 
as applicable, and the corrective actions taken;
    (ii) Summary information on the number, duration and cause 
(including unknown cause, if applicable) for monitor downtime incidents 
(other than downtime associated with zero and span or other daily 
calibration checks, if applicable); and
    (iii) A description of the actions taken to implement a QIP during 
the reporting period as specified in Sec. 64.8. Upon completion of a 
QIP, the owner or operator shall include in the next summary report 
documentation that the implementation of the plan has been completed 
and reduced the likelihood of similar levels of excursions or 
exceedances occurring.
    (b) General recordkeeping requirements. (1) The owner or operator 
shall comply with the recordkeeping requirements specified in 
Sec. 70.6(a)(3)(ii) of this chapter. The owner or operator shall 
maintain records of monitoring data, monitor performance data, 
corrective actions taken, any written quality improvement plan required 
pursuant to Sec. 64.8 and any activities undertaken to implement a 
quality improvement plan, and other supporting information required to 
be maintained under this part (such as data used to document the 
adequacy of monitoring, or records of monitoring maintenance or 
corrective actions).
    (2) Instead of paper records, the owner or operator may maintain 
records on alternative media, such as microfilm, computer files, 
magnetic tape disks, or microfiche, provided that the use of such 
alternative media allows for expeditious inspection and review, and 
does not conflict with other applicable recordkeeping requirements.


Sec. 64.10  Savings provisions.

    (a) Nothing in this part shall:
    (1) Excuse the owner or operator of a source from compliance with 
any existing emission limitation or standard, or any existing 
monitoring, testing, reporting or recordkeeping requirement that may 
apply under federal, state, or local law, or any other applicable 
requirements under the Act. The requirements of this part shall not be 
used to justify the approval of monitoring less stringent than the 
monitoring which is required under separate legal authority and are not 
intended to establish minimum requirements for the purpose of 
determining the monitoring to be imposed under separate authority under 
the Act, including monitoring in permits issued pursuant to title I of 
the Act. The purpose of this part is to require, as part of the 
issuance of a permit under title V of the Act, improved or new 
monitoring at those emissions units where monitoring requirements do 
not exist or are inadequate to meet the requirements of this part.
    (2) Restrict or abrogate the authority of the Administrator or the 
permitting authority to impose additional or more stringent monitoring, 
recordkeeping, testing, or reporting requirements on any owner or 
operator of a source under any provision of the Act, including but not 
limited to sections 114(a)(1) and 504(b), or state law, as applicable.
    (3) Restrict or abrogate the authority of the Administrator or 
permitting authority to take any enforcement action under the Act for 
any violation of an applicable requirement or of any person to take 
action under section 304 of the Act.

PART 70--STATE OPERATING PERMIT PROGRAMS

    1. The authority citation for part 70 continues to read as follows:

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

    2. Section 70.6 is amended by revising paragraphs (a)(3)(i)(A) and 
(c)(5)(iii) and (c)(5)(iv), and by removing (c)(5)(v) to read as 
follows:


Sec. 70.6  Permit content.

* * * * *
    (a) * * *
    (3) * * *
    (i) * * *
    (A) All monitoring and analysis procedures or test methods required 
under applicable monitoring and testing requirements, including part 64 
of this chapter and any other procedures and methods that may be 
promulgated pursuant to sections 114(a)(3) or 504(b) of the Act. If 
more than one monitoring or testing requirement applies, the permit may 
specify a streamlined set of monitoring or testing provisions provided 
the specified monitoring or testing is adequate to assure compliance at 
least to the same extent as the monitoring or testing applicable 
requirements that are not included in the permit as a result of such 
streamlining;
* * * * *
    (c) * * *
    (5) * * *
    (iii) A requirement that the compliance certification include all 
of

[[Page 54947]]

the following (provided that the identification of applicable 
information may cross-reference the permit or previous reports, as 
applicable):
    (A) The identification of each term or condition of the permit that 
is the basis of the certification;
    (B) The identification of the method(s) or other means used by the 
owner or operator for determining the compliance status with each term 
and condition during the certification period, and whether such methods 
or other means provide continuous or intermittent data. Such methods 
and other means shall include, at a minimum, the methods and means 
required under paragraph (a)(3) of this section. If necessary, the 
owner or operator also shall identify any other material information 
that must be included in the certification to comply with section 
113(c)(2) of the Act, which prohibits knowingly making a false 
certification or omitting material information;
    (C) The status of compliance with the terms and conditions of the 
permit for the period covered by the certification, based on the method 
or means designated in paragraph (c)(5)(iii)(B) of this section. The 
certification shall identify each deviation and take it into account in 
the compliance certification. The certification shall also identify as 
possible exceptions to compliance any periods during which compliance 
is required and in which an excursion or exceedance as defined under 
part 64 of this chapter occurred; and
    (D) Such other facts as the permitting authority may require to 
determine the compliance status of the source.
    (iv) A requirement that all compliance certifications be submitted 
to the Administrator as well as to the permitting authority.
* * * * *

PART 71--FEDERAL OPERATING PERMITS PROGRAMS

    1. The authority citation for part 71 continues to read as follows:

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

    2. Section 71.6 is amended by revising paragraphs (a)(3)(i)(A), 
(a)(3)(iii)(C), (c)(5)(iii) and (c)(5)(iv), and by removing (c)(5)(v) 
to read as follows:


Sec. 71.6  Permit content.

* * * * *
    (a) * * *
    (3) * * *
    (i) * * *
    (A) All monitoring and analysis procedures or test methods required 
under applicable monitoring and testing requirements, including part 64 
of this chapter and any other procedures and methods that may be 
promulgated pursuant to sections 114(a)(3) or 504(b) of the Act. If 
more than one monitoring or testing requirement applies, the permit may 
specify a streamlined set of monitoring or testing provisions provided 
the specified monitoring or testing is adequate to assure compliance at 
least to the same extent as the monitoring or testing applicable 
requirements that are not included in the permit as a result of such 
streamlining;
* * * * *
    (iii) * * *
    (C) For purposes of paragraph (a)(3)(iii)(B) of this section, 
deviation means any situation in which an emissions unit fails to meet 
a permit term or condition. A deviation is not always a violation. A 
deviation can be determined by observation or through review of data 
obtained from any testing, monitoring, or recordkeeping established in 
accordance with paragraphs (a)(3)(i) and (a)(3)(ii) of this section. 
For a situation lasting more than 24 hours which constitutes a 
deviation, each 24 hour period is considered a separate deviation. 
Included in the meaning of deviation are any of the following:
    (1) A situation where emissions exceed an emission limitation or 
standard;
    (2) A situation where process or emissions control device parameter 
values indicate that an emission limitation or standard has not been 
met;
    (3) A situation in which observations or data collected 
demonstrates noncompliance with an emission limitation or standard or 
any work practice or operating condition required by the permit;
    (4) A situation in which an exceedance or an excursion, as defined 
in part 64 of this chapter, occurs.
* * * * *
    (c) * * *
    (5) * * *
    (iii) A requirement that the compliance certification include all 
of the following (provided that the identification of applicable 
information may cross-reference the permit or previous reports, as 
applicable):
    (A) The identification of each term or condition of the permit that 
is the basis of the certification;
    (B) The identification of the method(s) or other means used by the 
owner or operator for determining the compliance status with each term 
and condition during the certification period, and whether such methods 
or other means provide continuous or intermittent data. Such methods 
and other means shall include, at a minimum, the methods and means 
required under paragraph (a)(3) of this section. If necessary, the 
owner or operator also shall identify any other material information 
that must be included in the certification to comply with section 
113(c)(2) of the Act, which prohibits knowingly making a false 
certification or omitting material information;
    (C) The status of compliance with the terms and conditions of the 
permit for the period covered by the certification, based on the method 
or means designated in paragraph (c)(5)(iii)(B) of this section. The 
certification shall identify each deviation and take it into account in 
the compliance certification; and
    (D) Such other facts as the permitting authority may require to 
determine the compliance status of the source.
    (iv) A requirement that all compliance certifications be submitted 
to the Administrator as well as to the permitting authority.
* * * * *
[FR Doc. 97-27264 Filed 10-21-97; 8:45 am]
BILLING CODE 6560-50-P