[Federal Register Volume 66, Number 128 (Tuesday, July 3, 2001)]
[Proposed Rules]
[Pages 35126-35155]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-16426]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 63, 264, 265, 266, and 270

[FRL-7001-9]
RIN 2050-AE79


NESHAP: Standards for Hazardous Air Pollutants for Hazardous 
Waste Combustors--Proposed Amendments

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: Under the Clean Air Act (CAA), EPA established new emissions 
standards for hazardous waste burning cement kilns, lightweight 
aggregate kilns, and incinerators on September 30, 1999 (NESHAP: Final 
Standards for Hazardous Air Pollutants for Hazardous Waste Combustors). 
Following promulgation of this final rule, the regulated community, 
through informal comments and through litigation, raised numerous 
issues related to specific requirements of the final rule. In response 
to relevant concerns, we are proposing and taking comment on certain 
targeted changes to the final rule. These regulatory changes do not 
propose to amend the numerical emission standards, but rather focus on 
improvements to the implementation of the emission standards, primarily 
in the areas of compliance, testing and monitoring.

DATES: Comments must be submitted by August 17, 2001.

ADDRESSES: If you wish to comment on this proposed rule, you must send 
an original and two copies of the comments referencing Docket Number F-
2001-RC5P-FFFFF to: RCRA Information Center (RIC), Office of Solid 
Waste (5305G), U.S. Environmental Protection Agency Headquarters (EPA 
HQ), Ariel Rios Building, 1200 Pennsylvania Avenue, NW, Washington, 
D.C. 20460-0002; or, (2) if using special delivery, such as overnight 
express service: RIC, Crystal Gateway One, 1235 Jefferson Davis 
Highway, First Floor, Arlington, VA 22202. You may also submit comments 
electronically following the directions in the Supplementary 
Information section below.
    You may view public comments and supporting materials in the RIC. 
The RIC is open from 9 am to 4 pm Monday through Friday, excluding 
Federal holidays. To review docket materials, we recommend that you 
make an appointment by calling 703-603-9230. You may copy up to 100 
pages from any regulatory document at no charge. Additional copies cost 
$ 0.15 per page. For information on accessing an electronic copy of the 
data base, see the Supplementary Information section.

FOR FURTHER INFORMATION CONTACT: For general information, call the RCRA 
Call Center at 1-800-424-9346 or TDD 1-800-553-7672 (hearing impaired). 
Callers within the Washington Metropolitan Area must dial 703-412-9810 
or TDD 703-412-3323 (hearing impaired). The RCRA Call Center is open 
Monday-Friday, 9 am to 4 pm, Eastern Standard Time. For more 
information on specific aspects of this proposed rule, contact Mr. 
Frank Behan at 703-308-8476, [email protected], or write him at the 
Office of Solid Waste, 5302W, U.S. EPA, Ariel Rios Building, 1200 
Pennsylvania Avenue, NW, Washington, D.C. 20460.

SUPPLEMENTARY INFORMATION:

Submittal of Comments

    You may submit comments electronically by sending electronic mail 
through the Internet to: [email protected]. You should 
identify comments in electronic format with the docket number F-2001-
RC5P-FFFFF. You must submit all electronic comments as an ASCII (text) 
file, avoiding the use of special characters or any type of encryption. 
The official record for this action will be kept in the paper form. 
Accordingly, we will transfer all comments received electronically into 
paper form and place them in the official record which will also 
include all comments submitted directly in writing. The official record 
is the paper record maintained at the RIC as described above. We may 
seek clarification of electronic comments that are garbled in 
transmission or during conversion to paper form.
    You should not electronically submit any confidential business 
information (CBI). You must submit an original and two copies of CBI 
under separate cover to: RCRA CBI Document Control Officer, Office of 
Solid Waste (5305W), U.S. EPA, Ariel Rios Building, 1200 Pennsylvania 
Avenue, NW, Washington, D.C. 20460.
    If you do not submit comments electronically, we are asking 
prospective commenters to voluntarily submit one additional copy of 
their comments on labeled personal computer diskettes in ASCII (text) 
format or a word processing format that can be converted to ASCII 
(text). It is essential that you specify on the disk label the word 
processing software and version/edition as well as the commenter's 
name. This will allow us to convert the comments into one of the word 
processing formats used by the Agency. Please use mailing envelopes 
designed to protect the diskettes. We emphasize that submission of 
diskettes is not mandatory, nor will it result in any advantage or 
disadvantage to any commenter.

Acronyms Used in the Rule

APCD--Air pollution control device
ASME--American Society of Mechanical Engineers
CAA--Clean Air Act
CEMS--Continuous emissions monitors/monitoring system
COMS--Continuous opacity monitoring system
CFR--Code of Federal Regulations
DOC--Documentation of Compliance
DRE--Destruction and removal efficiency
dscf--Dry standard cubic feet
dscm--Dry standard cubic meter
EPA/USEPA--United States Environmental Protection Agency
gr--Grains
HAP--Hazardous air pollutant
HWC--Hazardous waste combustor
MACT--Maximum Achievable Control Technology
NESHAP--National Emission Standards for HAPs
ng--Nanograms
NIC--Notice of Intent to Comply
NOC--Notification of compliance
OPL--Operating parameter limit
PM--Particulate matter
POHC--Principal organic hazardous constituent
ppmv--Parts per million by volume
RCRA--Resource Conservation and Recovery Act
TEQ--Toxicity equivalence

[[Page 35127]]

Table of Contents

Part One: Overview and Background for This Proposed Rule
I. What Is the Purpose of This Proposed Rule?
II. What Is the Phase I Rule?
III. What Related Actions Have Been Taken Since Publication of the 
Phase I Rule?
IV. How Can I Influence EPA's Thinking on this Rule?
Part Two: NESHAP--Proposed Amendments to the HWC Final Rule
I. Definition of Research, Development, and Demonstration Sources
II. Identification of an Organics Residence Time that is Independent 
of and Shorter than the Hazardous Waste Residence Time
III. Controls on APCDs after the Hazardous Waste Residence Time Has 
Expired
IV. Instantaneous Monitoring of Combustion Zone Pressure
V. Operator Training and Certification
VI. Bag Leak Detection System
VII. Time Extensions For Performance Testing if the Test Plan Has 
Not Been Approved
VIII. Flexibility in Operations During Confirmatory Performance 
Testing for Dioxin/Furan
IX. Waiving Operating Parameter Limits during Performance Testing
X. Method 23 as an Alternative to Method 0023A for Dioxin/Furans
XI. Calibration Requirements for Thermocouples
XII. Alternative Approach to Establish Operating Parameter Limits
XIII. Extrapolation of Operating Parameter Limits
XIV. Limit on Minimum Combustion Chamber Temperature for Cement 
Kilns
XV. Revisions to Operating Requirements for Activated Carbon 
Injection and Carbon Bed Systems
XVI. Clarification of Requirements to Confirm Carbon Bed Age
XVII. Revisions to Operating Parameter Limits for Wet Scrubbers
XVIII. Reproposal of kVA Limits for Electrostatic Precipitators and 
Request for Comment on Approaches to Ensure Baghouse Performance
XIX. How to Comply Temporarily with Alternative, Otherwise 
Applicable MACT Standards
XX. RCRA Permitting Requirements for Sources Entering the RCRA 
Process Post-Rule Promulgation
Part Three: Analytical and Regulatory Requirements
I. Executive Order 12866
II. Regulatory Flexibility Act (RFA), as Amended by the Small 
Business Regulatory Enforcement Fairness Act of 1996 (SBREFA), 5 
U.S.C. 601 et. seq.
III. Executive Order 13045: ``Protection of Children from 
Environmental Health Risks and Safety Risks''
IV. Environmental Justice Executive Order 12898
V. Unfunded Mandates Reform Act
VI. Executive Order 13132 (Federalism)
VII. Consultation with Tribal Governments
VIII. Paperwork Reduction Act
IX. National Technology Transfer and Advancement Act of 1995
Part Four: State Authority

Part One: Overview and Background for This Proposed Rule

I. What Is the Purpose of This Proposed Rule?

    Today's notice proposes specific changes to the NESHAP: Final 
Standards for Hazardous Air Pollutants for Hazardous Waste Combustors 
(Phase I) rule, published September 30, 1999 (64 FR 52828). After 
promulgation, commenters (primarily the regulated community) raised 
numerous potential issues through informal comments and during 
litigation settlement discussions. After considering the issues raised, 
we have decided to propose for comment twenty amendments to the final 
rule, most of the proposed changes relating to compliance and 
implementation of the rule.
    The ability of facilities to meet the September 30, 2002 compliance 
date may be dependent upon when these proposed changes are made final. 
While we expect to complete the rulemaking process and publish final 
amendments in a timely manner, we request comments on how the timing of 
these rule changes could impact compliance. In addition, we solicit 
comments on solutions to address compliance problems should they arise 
(e.g., use of Sec. 63.1206(b)(4) to obtain an extension of compliance 
with the emission standards of up to one year).
    In the ``Rules and Regulations'' section of the Federal Register, 
we are taking direct final action on thirteen additional amendments to 
the Phase I rule. If you wish to comment on those amendments, you must 
submit comments following the directions in the Addresses section of 
that action.
    The remaining sections of this part provide additional background 
information on the Phase I final rule.

II. What Is the Phase I Rule?

    In the Phase I final rule, we adopted National Emissions Standards 
for Hazardous Air Pollutants to control toxic emissions from the 
burning of hazardous waste in incinerators, cement kilns, and 
lightweight aggregate kilns. These emission standards created a 
technology-based national cap for hazardous air pollutant emissions 
from the combustion of hazardous waste in these devices. Additional 
risk-based conditions necessary to protect human health and the 
environment may be imposed (assuming a proper, site-specific 
justification) under section 3005(c)(3) of the Resource Conservation 
and Recovery Act (RCRA).
    Section 112 of the CAA requires emissions standards for hazardous 
air pollutants to be based on the performance of the Maximum Achievable 
Control Technology (MACT). These standards apply to the three major 
categories of hazardous waste burners--incinerators, cement kilns, and 
lightweight aggregate kilns. For purposes of today's proposal, we refer 
to these three categories collectively as hazardous waste combustors 
(HWC). Hazardous waste combustors burn about 80% of the hazardous waste 
combusted annually within the United States. The Phase I HWC MACT 
standards are expected to achieve significant reductions in the amount 
of hazardous air pollutants being emitted each year.
    Additionally, the Phase I HWC MACT rule satisfies our obligation 
under RCRA (the main statute regulating hazardous waste management) to 
ensure that hazardous waste combustion is conducted in a manner 
protective of human health and the environment. By using both CAA and 
RCRA authorities in a harmonized fashion, we consolidate regulatory 
control of hazardous waste combustion into a single set of regulations, 
thereby minimizing the potential for conflicting or duplicative federal 
requirements.
    More information on the Phase I HWC MACT rule is available 
electronically from the World Wide Web at www.epa.gov/hwcmact.

III. What Related Actions Have Been Taken Since Publication of the 
Phase I Rule?

    On November 19, 1999, we issued a technical correction to the Phase 
I HWC MACT final rule (64 FR 63209). It clarified our intent with 
respect to certain aspects of the Notification of Intent to Comply and 
Progress Report requirements of the 1998 ``Fast Track'' final rule (63 
FR 33783). Additionally, specific to the Phase I HWC MACT final rule, 
we corrected several typographical errors and omissions.
    On July 10, 2000, we issued a second technical correction to the 
Phase I HWC MACT final rule (65 FR 42292). This action corrected 
additional typographical errors and clarified several issues to make 
the Phase I rule easier to understand and implement. This action also 
supplied one omission from the technical correction published on 
November 19, 1999, and made one correction to the related June 19, 1998 
``Fast Track'' final rule (63 FR 33783).
    On July 25, 2000, the Court of Appeals for the District of Columbia 
decided Chemical Manufacturers Association v. EPA, 217 F. 3d 861 (D.C. 
Cir. No. 99-1236). The court held that EPA had the legal authority to

[[Page 35128]]

promulgate a requirement of early cessation of hazardous waste burning 
activity for those sources not intending to comply with the MACT 
emission standards. However, the court also held that we had not 
adequately explained our reasons for imposing the early cessation 
requirement. As a result, the court vacated the early cessation 
requirement and the related Notice of Intent to Comply (NIC) and 
Progress Report requirements. This vacature took effect on October 11, 
2000. Since the requirements were not vacated until after sources were 
required to submit their NICs (on October 2, 2000), we determined that 
the court's action does not impact a source's ability to request a RCRA 
permit modification using the streamlined procedures of 40 CFR 
270.42(j)(1). As long as a source complied with the NIC provisions 
(including filing the NIC before the provision was vacated), the source 
has met the requirements in 40 CFR 270.42(j)(1) and is therefore 
eligible for the streamlined RCRA permit modification process. The 
court's decision does not impact the emission standards or compliance 
schedule for the other requirements of the HWC NESHAP Subpart EEE.
    On November 9, 2000, we issued a third technical correction to the 
Phase I HWC MACT final rule (65 FR 67268). It clarified our intent with 
respect to the applicability of new source versus existing source 
standards for hazardous waste incinerators. This action also clarified 
three issues to make the Phase I rule easier to understand and 
implement.
    On May 14, 2001, we issued a final rule implementing two court 
orders that removed affected provisions of the Phase I HWC MACT final 
rule from the Code of Federal Regulations (66 FR 24270). This action 
removed the Notice of Intent to Comply provisions (discussed above) and 
certain operating parameter limits of baghouses and electrostatic 
precipitators.

IV. How Can I Influence EPA's Thinking on This Rule?

    In developing this proposal, we tried to address the concerns of 
all our stakeholders. Your comments will help us improve this rule. We 
invite you to provide different views on options we propose, new 
approaches we haven't considered, new data, how this rule may effect 
you, or other relevant information. We welcome your views on all 
aspects of this proposed rule. Your comments will be most effective if 
you follow the suggestions below:
     Explain your views as clearly as possible and why you feel 
that way.
     Provide solid technical and cost data to support your 
views.
     If you estimate potential costs, explain how you arrived 
at the estimate.
     Tell us which parts you support, as well as those you 
disagree with.
     Provide specific examples to illustrate your concerns.
     Offer specific alternatives.
     Refer your comments to specific sections of the proposal, 
such as the units or page numbers of the preamble, or the regulatory 
sections.
     Make sure to submit your comments by the deadline in this 
notice.
     Be sure to include the name, date, and docket number with 
your comments.

Part Two: NESHAP--Proposed Amendments to the HWC Final Rule

I. Definition of Research, Development, and Demonstration Sources

    Section 63.1200, Table 1, exempts research, development, and 
demonstration sources from the Part 63, Subpart EEE, hazardous waste 
combustor MACT standards.\1\ We explained at promulgation that the 
hazardous waste combustor emission standards and compliance assurance 
requirements may not be appropriate for these sources because of their 
typically intermittent operations and small size. See 64 FR at 52839.
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    \1\ Hazardous waste research, development, and demonstration 
sources remain subject to RCRA permit requirements under 
Sec. 270.65. See 64 FR at 52839.
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    The rule defines research, development, or demonstration sources as 
those sources engaged in laboratory, pilot plant, or prototype 
demonstration operations: (1) Whose primary purpose is to conduct 
research, development, or short-term demonstration of an innovative and 
experimental hazardous waste treatment technology or process; and (2) 
where the operations are under the close supervision of technically-
trained personnel.
    Stakeholders express concern that the definition of demonstration 
source and the provision to allow unlimited one-year time extensions to 
the exemption may result in commercial, production sources taking 
inappropriate advantage of the exemption. We request comment on 
approaches to preclude inappropriate use of the exemption for 
demonstration sources. Approaches that we are considering include: (1) 
Clearly distinguishing between research and development sources versus 
demonstration sources, and limiting the exemption for demonstration 
sources to one year or less; or (2) requiring documentation of how a 
source's demonstration of an innovative or experimental hazardous waste 
treatment technology or process is different from the waste management 
services provided by a commercial hazardous waste combustor.

II. Identification of an Organics Residence Time That Is 
Independent of and Shorter Than the Hazardous Waste Residence Time

    ``Hazardous waste residence time'' is defined at Sec. 63.1201(a) as 
the time elapsed from cutoff of the flow of hazardous waste into the 
combustor (including, for example, the time required for liquids to 
flow from the cutoff valve into the combustor) until solid, liquid, and 
gaseous materials from the hazardous waste, excluding residues that may 
adhere to combustion chamber surfaces, exit the combustion chamber. As 
stakeholders recognize, hazardous waste residence time has significant 
regulatory and enforcement implications. For example, if a source were 
to exceed an operating requirement or emission standard after the 
hazardous waste residence time has expired, it is not a violation if 
the exceedance occurred during start-up or shut-down, or because of a 
malfunction provided that the source follows the procedures and 
corrective measures prescribed in the start-up, shut-down, and 
malfunction plan. In addition, after the hazardous waste residence time 
has expired, sources may elect to comply with emission standards the 
Agency has promulgated under sections 112 and 129 of the Clean Air Act 
for source categories that do not burn hazardous waste in lieu of the 
hazardous waste combustor standards of Subpart EEE, Part 63. See 
Sec. 63.1206(b)(1). \2\
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    \2\ As discussed in Section XIX, if sources elect to comply 
temporarily with alternative section 112 or 129 MACT standards after 
the hazardous waste residence time has expired, sources nonetheless 
remain an affected source only under Subpart EEE for hazardous waste 
combustors.
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    Since promulgation of the hazardous waste combustor rule, 
stakeholders have raised the issue of whether a hazardous waste 
organics residence time should be defined that is independent of and 
shorter than the bulk solids residence time.
    Industry stakeholders recommend an approach to calculate a 
hazardous waste organics residence time that defines when organic 
constituents in solid materials have been destroyed. \3\ Although the 
concept has merit, several

[[Page 35129]]

issues must be addressed prior to revising the rule to allow sources to 
petition the Administrator for case-by-case determinations of an 
organics residence time. We therefore are not proposing a change at 
this time but are requesting comment on the concept and implementation 
of an organic residence time.
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    \3\ Email from David Case, Environmental Treatment Council, to 
Bob Holloway, EPA, with attachment entitled ``Proposed Method for 
Calculation of Hazardous Constituents Retention Time,'' dated June 
7, 2000.
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    As contemplated by stakeholders, the hazardous waste organics 
residence time would be independent of and considerably shorter than 
the bulk hazardous waste residence time discussed above. As with the 
bulk hazardous waste residence time, an organics residence time would 
have significant regulatory and enforcement implications. After the 
hazardous waste organics residence time has expired, an exceedance of 
the carbon monoxide or hydrocarbon emission standard or an operating 
parameter limit associated with the destruction and removal efficiency 
(DRE) or dioxin/furan emission standards would not be a violation if 
the exceedance occurred during start-up or shut-down or were caused by 
a malfunction and sources comply with the procedures and corrective 
measures prescribed in the start-up, shut-down, and malfunction plan. 
In addition, it seems appropriate to allow sources to elect to comply 
with standards the Agency has promulgated under sections 112 or 129 of 
the Clean Air Act to control organic emissions for source categories 
that do not burn hazardous waste in lieu of the hazardous waste 
combustor standards of Subpart EEE, Part 63. As discussed in Section 
III below, however, providing only a partial transition from the 
hazardous waste combustor MACT standards of Subpart EEE may be 
problematic.

A. What Is the Approach Stakeholders Recommend to Calculate Hazardous 
Waste Organics Residence Time?

    Stakeholders suggest that a hazardous waste organics residence time 
can be calculated as the sum of: (1) The time for the solid matrix 
containing the organic constituents to reach the target temperature 
required to destroy the organics; (2) the time for the organic 
constituent to be destroyed at the target temperature; and (3) the time 
for the gas to pass through the combustion chamber and exit the air 
pollution control system. The time required for the organic 
constituents within the solid matrix to reach the target temperature 
would be calculated using standard heat transfer equations which are 
available in chemical engineering references. \4\ Stakeholders state 
that these equations can be applied to various materials, assuming the 
thermal conductivity of the material. These equations also can be 
applied easily to various geometries, such as a 55 gallon drum (right 
circular cylinder), or to irregular shaped items resulting from 
shredder feed.
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    \4\ Geankoplis, C.J., ``Transport Processes and Unit 
Operations,'' Chapters 3 and 4, Allyn and Bacon, Inc., Boston, 1978.
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    Stakeholders state that once the solid is at the target temperature 
the time for the hazardous constituent to be destroyed can be 
calculated using equations that are readily available from Dr. 
Dellinger's work on developing the low oxygen thermal stability index 
for hazardous organic compound incinerability. \5\ Using Dellinger's 
kinetic models under low oxygen conditions, the destruction time for 
hazardous constituents can be calculated.
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    \5\ B. Dellinger, et al, ``Development of a Thermal Stability 
Based Index of Hazardous Waste Incinerability,'' University of 
Dayton Research Institute Final Report Under EPA Cooperative 
Agreement CR-813938, November 15, 1991. Also, B. Dellinger, et al, 
``Development of a Thermal Stability Based Index of Hazardous 
Organic Compound Incinerability,'' Environmental Science and 
Technology, 24, p.316, March 1990.
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    To implement this approach to calculate a hazardous waste organics 
residence time, stakeholders suggest that sources should include the 
retention time evaluation and calculations in a report developed by an 
independent Professional Engineer with combustion engineering 
expertise. Sources would submit the report to the Administrator for 
review and approval.

B. How Would Site-Specific Factors Be Addressed?

    Stakeholders state that the general approach can be readily applied 
to various scenarios as necessary on a site-specific basis. 
Stakeholders have considered how some scenarios could be addressed, as 
discussed below, and believe that approaches to address other scenarios 
would become apparent as the approach is applied to the site-specific 
situation.
1. How Would Various Geometric Shapes and Sizes of Solids Be Addressed?
    Stakeholders acknowledge that an incineration process can have 
several types of solid feed such as bulk solids, direct drum feed in 
various sizes, shredded waste feed, and other mechanisms. Each of these 
solid feed scenarios can be evaluated for the heat transfer step by 
assigning an appropriate geometry to the solid for use in the heat flux 
equations. Heat transfer will take place more rapidly in shredded waste 
feed, in which the particle size of the solids is reduced. At the other 
extreme is a monolith in a 55 gallon drum, which will require a longer 
time for the center point to reach the target temperature. The center 
point of the monolith can be considered the point where the organic 
constituent is located for ensuring a worst case for the heat transfer 
step. Site-specific feed can be modeled by evaluating the actual 
geometry and size of solid feed and post-shredder feed.
2. How Would the Thermal Conductivity of the Solid Be Determined?
    The time for the solid mass to reach temperature will depend on the 
thermal conductivity of the solid mass. The thermal conductivity is a 
key parameter in the heat transfer equation. The types of solid feed 
managed at a particular site can be used to select a worst case 
material for thermal conductivity. Stakeholders present as an example a 
facility that feeds certain polymeric monolithic materials in 55 gallon 
drums. Certain polymers may have a low thermal conductivity that can be 
used as a worst case. References such as Perry's Chemical Engineering 
Handbook can be consulted to provide a range of thermal conductivities 
for consideration. For example, stakeholders note that polypropylene 
has one of the lower thermal conductivities of 0.08 BTU/hr-sq.ft.- 
deg.F (see Table 23-10 in Perry's Handbook). This might provide a good 
worst case value to use for the solid mass thermal conductivity for 
this source.
3. How Would a Worst-Case Organic Constituent Be Selected?
    Stakeholders suggest that a worst-case hazardous organic 
constituent could be selected on the basis of its ranking in various 
incinerability indices, just as principal organic hazardous 
constituents (POHCs) are selected for demonstrating destruction and 
removal efficiency (DRE). A constituent that ranks high in both the 
heat of combustion and low oxygen thermal stability indices could be 
used. In addition, a few compounds with complex structures that would 
be expected to yield various decomposition byproducts could be modeled. 
Examples of such compounds are pentachlorophenol, perchloroethylene, 
and certain pesticides. Stakeholders suggest that Dr. Dellinger's work, 
cited above, can be consulted to select additional worst case 
constituents.

[[Page 35130]]

4. How Would the Target Destruction Temperature Be Selected?
    Stakeholders suggest that target destruction temperatures can be 
selected based on the kinetic studies of Dr. Dellinger. Stakeholders 
state that Dellinger has generally found that any organic chemical and 
its organic byproducts can be completely destroyed at 800 deg.C.\6\ 
Also, the range of destruction temperatures published by Dellinger can 
be consulted to select a target temperature on a site-specific basis 
for the types of wastes that are managed.
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    \6\ See Attachment 5 of ETC's Comments to the MACT Rule, Docket 
F-96-RCSP-FFFFF, filed August 19, 1996.
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5. How Would Paralytic and Starved Air Conditions Be Addressed?
    Stakeholders acknowledge that certain solid geometries may result 
in the organic constituent being isolated from combustion air, such 
that pyrolytic conditions must be assumed. Nonetheless, stakeholders 
state that a destruction time can still be calculated and the low 
oxygen conditions can be incorporated into the kinetic model. Dellinger 
has published such calculations in developing the low oxygen thermal 
stability index for incinerability.\7\ Stakeholders state that 
pyrolytic conditions would likely be required to be assumed for 
monolithic feed. They note that shredder-feed, however, substantially 
reduces the particle size of the solid feed, and mixing with combustion 
air is achieved.
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    \7\ Dellinger, B. et al, ``PIC Formation Under Pyrolytic and 
Starved Air Conditions,'' EPA Publication No. EPA/600/S2-86/006, 
July 1986.
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6. How Would Heat Sink and Other Heat Consuming Factors Be Addressed?
    Stakeholders acknowledge that other factors in a given waste may 
consume energy, requiring another step or two to the retention time 
calculation. For example, a solid waste monolith that is a low melting 
point solid will go through a melting transition that will consume heat 
before the temperature of the mass rises past the transition point. 
Stakeholders state that this step can be easily added to the retention 
time calculation, if necessary. Similarly, a waste may contain a pocket 
of water or other low boiling point material, and a step for enthalpy 
of vaporization may need to be added. Stakeholders note that these 
calculations can also be performed as a form of sensitivity analysis to 
determine how conservative the retention time calculation is.

B. What Are the Unresolved Issues About Stakeholders' Recommended 
Approach?

    We acknowledge that the residence time for organic constituents in 
a solid matrix is generally less than the residence time for the bulk 
hazardous waste residue. Thus, ideally, sources should be eligible for 
the reduced regulatory and enforcement burden discussed above once the 
organics residence time has expired. One promising feature of the 
stakeholders' approach is that it would conservatively predict how long 
it takes the waste monolith to heat up to volatilize the organic 
constituent. We are concerned, however, that their approach does not 
explicitly address how long it would take for: (1) The generated 
volatiles or their potentially toxic intermediates to diffuse to the 
surface of the monolith where oxygen is present for destruction; or (2) 
alternatively for oxygen in the bulk gas to diffuse from the surface of 
the monolith to reach the volatiles. In lieu of accounting for the time 
required to destroy organic constituents under oxidative conditions, 
stakeholders' approach assumes that destruction would occur within 
solid matrices under pyrolytic conditions. Further, stakeholders 
believe that calculations developed by Dellinger while developing the 
low oxygen thermal stability index could be used to model those 
pyrolytic reactions. We request comments on whether Dellinger's work on 
low oxygen destruction would adequately model destruction under the 
pyrolytic conditions that occur within solid matrices, with respect to 
either the time required for destruction of the initial organic 
constituent or the types of intermediates that would be formed and the 
time required to destroy the intermediates. Finally, we request 
comments on whether it is practicable to perform valid engineering 
calculations for multiple waste streams that are not homogenous and 
that contain multiple organic constituents of concern.
    We request comment on stakeholders' approach to calculate an 
organics residence time and specifically whether it can be revised to 
address our concerns.

III. Controls on APCDs After the Hazardous Waste Residence Time Has 
Expired

    For sources equipped with a dry particulate matter control device, 
we propose to maintain the semivolatile metal, low volatile metal, and 
particulate matter \8\ emission standards and the associated 
particulate matter control device operating requirements after the 
hazardous waste residence time has expired and until the control device 
undergoes a complete cleaning cycle (e.g., for all compartments of a 
baghouse; for all fields of an electrostatic precipitator).\9\ For 
sources equipped with activated carbon injection, the dioxins/furans 
and mercury emission standards would also continue to apply after the 
hazardous waste residence time has expired until the control device 
undergoes a complete cleaning cycle.
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    \8\ The particulate matter emission standard is included because 
particulate matter is a surrogate for metal hazardous air pollutants 
other than mercury, the enumerated semivolatile metals, and the 
enumerated low volatile metals.
    \9\ If sources comply with the semivolatile and low volatile 
metal emission standards without emissions testing by assuming all 
metals in feedstreams are emitted, and therefore do not rely on the 
particulate matter control device to comply with the emission 
standards for these metals, the proposed requirements to maintain 
compliance with the semivolatile and low volatile metals emission 
standards and control device operating parameter limits would not 
apply.
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A. What Concern Would This Requirement Address?

    Dry particulate matter emission control devices such as 
electrostatic precipitators and baghouses retain collected particulate 
matter in the device until the sections of the device are cleaned 
sequentially, e.g., rapping of electrostatic precipitator plates, bag 
cleaning. This retained particulate matter contains metal hazardous air 
pollutants other than mercury due to its volatility. In addition, if 
the source is equipped with activated carbon injection, the collected 
particulate matter also will contain mercury and dioxins/furans. Our 
concern is that these pollutants could be emitted at levels exceeding 
the hazardous waste combustor emission standards after the hazardous 
waste residence time has expired.
    After the hazardous waste residence time has expired, sources may 
choose to comply with MACT standards the Agency has promulgated under 
sections 112 and 129 of the Clean Air Act for source categories that do 
not burn hazardous waste in lieu of the Subpart EEE standards. See 
Sec. 63.1206(b)(1). \10\ If sources choose to comply with those

[[Page 35131]]

otherwise applicable MACT standards, we are concerned that these 
standards may not adequately ensure that the hazardous waste-derived 
pollutants remaining in the dry particulate matter control device are 
controlled to the level required by the hazardous waste combustor rules 
of Subpart EEE. For example, if the alternative particulate matter 
standard were substantially higher than the hazardous waste combustor 
MACT standard, sources may be able to operate the control device under 
less stringent operating levels (e.g., lower power to a field of an 
electrostatic precipitator) which could cause the accumulated 
particulate matter (containing hazardous waste-derived pollutants) 
retained within the device to be reentrained in the stack gas. This 
could allow hazardous waste-derived pollutants to be emitted at levels 
exceeding the hazardous waste combustor MACT emission standards. When 
the particulate matter control device undergoes a complete cleaning 
cycle, the accumulated hazardous waste-derived pollutants are removed, 
thus precluding an exceedance of the hazardous waste combustor emission 
standards.
---------------------------------------------------------------------------

    \10\ As discussed in Section XIX of the text, if sources choose 
to comply with otherwise applicable section 112 or 129 requirements 
(e.g., Subpart LLL for cement kilns) after the hazardous waste 
residence time has expired, sources remain an affected source under 
Subpart EEE only. Sources would comply with those otherwise 
applicable MACT standards under an alternative mode of operation 
that sources would specify under Sec. 63.1209(q).
---------------------------------------------------------------------------

B. Is It Necessary To Require Continued Compliance With the Limit on 
Gas Temperature at the Inlet to the Dry Particulate Matter Control 
Device?

    We considered whether increasing the gas temperature at the inlet 
to the dry particulate matter control device, absent a requirement to 
maintain the temperature operating limit, could cause hazardous waste-
derived semivolatile metals (and mercury and dioxins/furans if sources 
use activated carbon injection) contained in the accumulated 
particulate matter to volatilize and be emitted at levels that exceed 
an emission standard.
    We initially conclude that, absent a gas inlet temperature limit, 
gas temperatures are not likely to increase to the levels necessary to 
volatilize enough semivolatile metals to cause an exceedance of the 
emission standards. This is particularly true if we consider that many 
sources should be able to complete a cleaning cycle of their 
electrostatic precipitator or baghouse within 30 minutes after the 
hazardous waste residence time has expired. We are concerned, however, 
that, for sources equipped with activated carbon injection, increases 
in inlet gas temperatures above the operating limit may potentially 
revolatilize captured mercury and dioxins/furans. We request comment on 
the extent to which mercury and dioxins/furans may revolatilize and be 
emitted because of increased gas temperatures in the short period after 
the hazardous waste residence time has expired and the cleaning cycle 
for the dry particulate matter control device has been completed.

C. Would the Proposed Requirement Increase Cleaning Cycle Frequency and 
Potentially Emissions of Hazardous Air Pollutants?

    As discussed above, we propose to require continued compliance with 
the semivolatile metal, low volatile metal, and particulate matter 
standards (and the dioxin/furan and mercury standards if sources use 
carbon injection) after the hazardous waste residence time has expired 
until the dry particulate matter control device undergoes a complete 
cleaning cycle. However, we are concerned, that unless additional 
controls are applied, this requirement could potentially result in an 
increase in particulate emissions and associated hazardous air 
pollutants.
    When a dry particulate matter control device is cleaned, collection 
efficiency is temporarily degraded. For example, when the plates in the 
last field of an electrostatic precipitator are rapped, some of the 
resuspended particulate matter is unavoidably emitted. For baghouses, 
when the bags are cleaned, typically using a pulse of air, the 
collection efficiency of the cleaned bags is reduced until a layer of 
particulate matter reforms on the bags. Thus, increasing the cleaning 
frequency of a baghouse decreases its collection efficiency.
    To comply with the proposed requirement to clean the particulate 
matter control device before the Subpart EEE metals and particulate 
matter standards are waived in lieu of other standards, sources may 
want to initiate a cleaning cycle immediately after the hazardous waste 
residence time has expired. Further, they may want to restart the 
timing of the cleaning cycle beginning with the cleaning that occurs 
after the hazardous waste residence time has expired. Increasing the 
cleaning cycle frequency could potentially result in an exceedance of 
the emission standards, however, if compliance with the standards has 
not been demonstrated during performance testing at that cleaning cycle 
frequency. To ensure that the emission standards are not exceeded due 
to increased cleaning cycle frequency, sources may not increase the 
cleaning cycle frequency beyond the frequency used during the 
comprehensive performance test.

D. How Would This Requirement Be Implemented?

    If sources elect to comply temporarily with the otherwise 
applicable section 112 or 129 Clean Air Act standards after the 
hazardous waste residence time has expired, sources would remain 
subject to certain Subpart EEE standards and associated compliance 
requirements until sources completed a cleaning cycle of the dry 
particulate matter control device: Particulate matter, semivolatile 
metals, low volatile metals, and, if sources use activated carbon 
injection, dioxin/furan and mercury. Given that sources remain an 
affected source only under Subpart EEE when sources elect to comply 
temporarily with otherwise applicable MACT standards, sources would 
identify this operating scenario as an alternative mode of operation 
under Sec. 63.1209(q).\11\ Consequently, sources would specify the 
applicable emission standards and compliance requirements for this 
alternative mode of operation as: (1) Those standards and compliance 
requirements of Subpart EEE that remain in effect; and (2) those 
otherwise applicable standards and compliance requirements established 
under section 112 or 129 (e.g., Subpart LLL for cement kilns). If an 
otherwise applicable section 112 or 129 standard or compliance 
requirement were more stringent than a Subpart EEE standard or 
compliance requirement that remains in effect, sources would comply 
with the more stringent standard or compliance requirement.
---------------------------------------------------------------------------

    \11\ See Section XIX below in the text for additional discussion 
on using Sec. 63.1209(q) to specify operations under otherwise 
applicable section 112 or 129 MACT standards.
---------------------------------------------------------------------------

    Exceedance of a Subpart EEE operating parameter limit (OPL) for a 
dry particulate matter control device after the hazardous waste 
residence time has expired but before a cleaning cycle of the device 
has been completed would be evidence of failure to maintain compliance 
with the Subpart EEE emission standards. Given that the hazardous waste 
residence time has expired, however, the exceedance need not be 
considered for the excessive exceedance reporting requirement under 
Sec. 63.1206(c)(vi). Similarly, if the exceedance occurs because of a 
malfunction, the exceedance would not be evidence of failure to 
maintain compliance with an emission standard if the source followed 
the corrective measures prescribed in its startup, shutdown, and 
malfunction plan. Thus, the consequences of an exceedance would be the 
same after the hazardous waste residence time has expired whether the 
exceedance occurs before or

[[Page 35132]]

after the cleaning cycle has been completed if the source chose to 
continue to comply with the Subpart EEE emission standards (i.e., in 
lieu of otherwise applicable MACT standards under a different mode of 
operation). Having equivalent consequences of an exceedance of an OPL 
after the hazardous waste residence time has expired irrespective of 
whether the cleaning cycle has been completed is appropriate. Our 
objective is simply to ensure that the Subpart EEE OPLs for the dry 
particulate matter control device are maintained until the cleaning 
cycle is completed to minimize emissions of hazardous waste-derived 
HAPs to below the Subpart EEE emissions standards. Our intent is not to 
penalize a source for exceedances that may be attributable to 
unavoidable malfunctions after the source has taken the preventative 
measures to minimize emissions of HAPs by cutting off the hazardous 
waste feed and allowing the hazardous waste residence time to expire.
    Some stakeholders have expressed initial concern with the technical 
feasibility of these proposed requirements. We will be considering 
these concerns prior to issuing a final rule.

IV. Instantaneous Monitoring of Combustion Zone Pressure

    The final rule requires sources to control combustion system leaks 
by either: (1) Keeping the combustion zone sealed; (2) maintaining the 
maximum combustion zone pressure lower than the ambient pressure 
measured using an instantaneous monitor; or (3) using an alternative 
means to provide control of system leaks. See Secs. 63.1201(a), 
63.1206(c)(5)(ii), and 63.1209(p). The rule defines an ``instantaneous 
monitor'' as one that continuously samples, detects and records the 
regulated parameter without use of an averaging period. In today's 
notice, we propose to revise the combustion system leak requirements to 
better clarify the intent of this provision, and we are taking comment 
on whether we should allow sources to average pressure readings over 
short periods of time when demonstrating that their combustion system 
is maintained below ambient pressure.
    After publication of the final rule, stakeholders expressed concern 
that the requirement to maintain the combustion zone pressure lower 
than ambient pressure (option 2 above) could result in an overly 
prescriptive requirement. Stakeholders believe this regulatory language 
can be interpreted to require sources to monitor and record combustion 
zone pressure at a frequency of every 50 milliseconds.\12\ Stakeholders 
state such an interpretation would be problematic because of the 
enormous number of data points that must be recorded and because such a 
frequent monitoring frequency would greatly increase the number of 
automatic waste feed cutoffs. Stakeholders also requested that we 
clarify that combustion system leaks refer to fugitive emissions 
resulting from the combustion of hazardous waste, and not fugitive 
emissions that originate from nonhazardous process streams (e.g., the 
clinker product at a cement kiln).
---------------------------------------------------------------------------

    \12\ The final rule preamble states that typical pressure 
transducers in use today are capable of responding to pressure 
changes once every 50 milliseconds. See 64 FR 52920.
---------------------------------------------------------------------------

    After careful review of the regulatory language and after 
considering our original intent, we agree that the final rule is 
ambiguous and may be conservatively interpreted to require sources to 
monitor and record combustion zone pressure at a frequency of every 50 
milliseconds. Therefore, in today's notice, we clarify that our intent 
is to require sources to use a pressure monitor and recording frequency 
that is adequate to detect combustion system leak events. We also 
clarify that the intent of the combustion system leak requirement is to 
prevent fugitive emissions from the combustion of hazardous waste, not 
fugitive emissions that originate from nonhazardous process streams.
    To make these clarifications, we propose to modify the 
Sec. 63.1201(a) definition of an instantaneous pressure monitor to read 
as follows: ``Instantaneous monitoring for combustion system leak 
control means detecting and recording pressure without use of an 
averaging period, at a frequency adequate to detect combustion system 
leak events from hazardous waste combustion'' (emphasis added).\13\ We 
also propose to revise the Sec. 63.1209(p) automatic waste feed cutoff 
regulatory language to read as follows: ``If you comply with the 
requirements for combustion system leaks under Sec. 63.1206(c)(5) by 
maintaining the maximum combustion chamber zone pressure lower than 
ambient pressure to prevent combustion system leaks from hazardous 
waste combustion, sources must perform instantaneous monitoring of 
pressure and the automatic waste feed cutoff system must be engaged 
when negative pressure is not maintained'' (emphasis added).
---------------------------------------------------------------------------

    \13\ Note that this newly proposed definition removes the word 
``sampling'' from the definition of instantaneous pressure monitor 
because a pressure monitor is not thought to physically withdraw a 
combustion gas sample.
---------------------------------------------------------------------------

    We do not specify the monitoring and recording frequencies in the 
regulations, however, because sources differ in design and operation 
such that different monitoring and recording frequencies may be needed 
to ensure that fugitive emissions do not occur. Rather, sources and 
permit officials should determine on a site-specific basis what 
frequency of monitoring and recording would be appropriate. Each source 
should describe in the comprehensive performance test workplan and 
Notification of Compliance how their compliance method will ensure that 
fugitive emissions will not occur. We propose that this description 
specify the monitoring and recording frequency and how the monitoring 
approach will be integrated into the automatic waste feed cutoff 
system.
    Stakeholders also suggest that we allow averaging of the pressure 
readings over short periods of time, e.g., a 5-second rolling average 
updated every second, in demonstrating the combustion system is 
maintained below ambient pressure. Averaging of pressure readings is 
less stringent than the current final rule instantaneous monitoring 
requirements. We request comment on whether such a monitoring approach 
is appropriate, and specifically, whether averaging pressure readings 
can adequately detect pressure excursion events that result in 
combustion system leaks.

V. Operator Training and Certification

    On July 10, 2000, we issued a technical correction to the operator 
training and certification requirements of Sec. 63.1206(c)(6) to 
clarify which employees are subject to the training and certification 
requirements and to note that the training and certification program 
should be tailored to the responsibilities of the employee. See 65 FR 
at 42295. Subsequent to this technical correction, incinerator 
stakeholders raised concerns about the requirement for incinerator 
control room operators and shift supervisors to be trained and 
certified under the American Society of Mechanical Engineers (ASME) 
Standard Number QHO-1-1994. Although the rule allows incinerator 
control room operators to be trained and certified under either a State 
program or ASME's program, stakeholders note that they are required to 
use the ASME program because there are no State programs at this time. 
Stakeholders raise the following concerns: (1) The scope of the ASME 
training and certification program is too broad; (2) the ASME 
certification

[[Page 35133]]

program is problematic for new sources and newly hired operators 
because it requires 6 months of operating experience at the source 
before full certification may be awarded; (3) the ASME control room 
operator training and certification program is not necessary for shift 
supervisors; and (4) the ASME training and certification program cannot 
be implemented by the regulatory compliance date.
    We provide below our reasons for preferring the ASME training and 
certification program over site-specific, source-implemented programs, 
but acknowledge stakeholders' concerns that the program may be more 
comprehensive than necessary to ensure compliance with the requirements 
of Subpart EEE. Accordingly, we propose to allow incinerator control 
room operators to be trained and certified under: (1) A site-specific, 
source-developed and implemented program; (2) the ASME program; or (3) 
a State program. We also conclude that it may be difficult for sources 
that choose to use the ASME program to fully certify their control room 
operators by the compliance date. Therefore, we propose to require only 
provisional certification by the compliance date for such sources. In 
addition, for sources that choose to use the ASME program, only 
provisional certification would be required for new employees and 
employees at new facilities prior to their assuming duties. Finally, we 
propose that control room operator training and certification is not 
necessary for shift supervisors to help ensure that the source operates 
within the limits established under the rule and that emissions of 
hazardous air pollutants are minimized.

A. How Do We Address Concerns About the ASME Training and Certification 
Program?

1. Is the Scope of the ASME Program Too Broad?
    Incinerator stakeholders state that the scope of the ASME training 
and certification program for incinerator control room operators is too 
broad to apply generically to all control room operators. They prefer a 
tailored, site-specific, source-developed and implemented training and 
certification program.
    The ASME program requires that control room operators be trained 
and certified to ensure a broad knowledge of operational, preventive 
maintenance, safety procedures, and practices for various types of 
incineration systems, emission control systems, and continuous 
emissions monitoring systems. Incinerator stakeholders state that there 
is no obvious benefit of requiring a broad knowledge of incineration 
issues; knowledge of only the equipment and operations at the 
operator's site are important. They question the benefit of, for 
example, an operator of a small liquid waste incinerator equipped with 
a wet scrubber knowing how to operate a rotary kiln incinerator 
equipped with a baghouse. They note further that it is unnecessarily 
time-consuming and stressful for operators that are unfamiliar with 
equipment they have never operated to undergo a rigorous training and 
certification program for that equipment. In addition, they note that 
the ASME standard was developed as a voluntary standard. Finally, they 
note that cement kiln and lightweight aggregate kiln control room 
operators may be trained and certified under a site-specific program.
    The ASME program is comprised of a broad training curriculum that 
is implemented by each source followed by a provisional certification 
that is administered by ASME. Provisional certification is awarded 
after the operator passes a comprehensive, generic written test 
addressing operations of various types of incinerators and control 
systems. Operators with provisional certification may apply to ASME for 
full certification. Full certification is awarded after passing an on-
site, site-specific oral examination.
    We continue to believe that a broad training and certification 
program can be beneficial. A broad training program may enable control 
room operators to recommend modifications to existing equipment or make 
recommendations for new equipment, which may reduce HAP emissions. In 
addition, certification under a broad training curriculum would avoid 
the retraining and recertification that would be required if the source 
modifies the design or operation of the unit in a manner that could 
affect compliance with the emission standards and operating 
requirements of Subpart EEE.
    Nonetheless, we agree with incinerator stakeholders that the broad 
scope of the ASME program may not be necessary to ensure compliance 
with the provisions of Subpart EEE. Accordingly, we propose to allow 
sources to use site-specific, source-developed and implemented training 
and certification programs, as discussed under Section B below.
2. Full Certification Under the ASME Program Cannot Be Achieved by the 
Compliance Date
    The rule currently requires full ASME (or State) certification by 
the compliance date. We agree with stakeholders that this is not 
workable because ASME does not have the resources to implement the 
site-specific oral examination requisite for full certification by the 
compliance date. After passing the written examination and achieving 
provisional certification, control room operators must apply to ASME 
for the oral examination. Stakeholders indicate that it will take one 
half day per control room operator to administer the site-specific oral 
examination. For many facilities, the ASME oral examination team \14\ 
will require approximately one week, including travel time, to 
administer the exam to all control room operators. Although ASME may 
train several examination teams, it is unlikely that full certification 
examinations can be implemented at all 149 hazardous waste incineration 
facilities prior to the compliance date.
---------------------------------------------------------------------------

    \14\ The examination team is comprised of representatives from 
ASME, the hazardous waste industry, the operator's facility, and/or 
the regulatory agency or jurisdictional authority applicable to the 
facility.
---------------------------------------------------------------------------

    To address this concern, we propose to require only provisional 
certification by the compliance date for sources that choose to use the 
ASME certification program. In addition, the operator would be required 
to submit an application to ASME for full certification and be 
scheduled for the certification examination. Finally, the operator 
would be required to achieve full certification within 1 year of the 
compliance date. We hope that providing this flexibility in the 
deadline for full certification will encourage use of the ASME program. 
We specifically request comment on whether the proposed deadlines for 
implementing the ASME certification program are appropriate.
3. Requiring Six Months of Operating Experience at the Source Before 
Full Certification Is Problematic
    The ASME standard requires that control room operators have six 
months of operating experience at the source before they can be fully 
certified. This is a problem for new sources and for newly hired 
operators. We propose to preclude this problem by requiring only 
provisional certification before operators at new sources and newly 
hired operators could assume their duties. Also, we would require that

[[Page 35134]]

provisionally certified operators apply to ASME for, and be scheduled 
for, full certification before they assume their duties. In addition, 
we would require that they achieve full certification within one year 
of assuming their duties. This will ensure that full certification will 
be achieved in a timely manner.

B. What Would Be the Requirements for Site-Specific, Source-Developed 
and Implemented Training and Certification Programs?

    Under today's proposed rule, a source could choose to develop and 
implement a site-specific training and certification program in lieu of 
the ASME program or a State program. Certification under a site-
specific program would be required by the compliance date given that 
the source will implement both the training and certification (i.e., 
written examination at a minimum). We note that cement and lightweight 
aggregate kiln sources are currently allowed to use site-specific 
training and certification programs because there is no ASME or other 
standard for these sources that addresses their hazardous waste burning 
activities. Because the requirements discussed below are appropriate 
for these sources as well, we propose to require that the requirements 
also apply to cement and lightweight aggregate kilns.
    We propose to specify a training curriculum to ensure that the 
scope of the training is sufficient to ensure the control room operator 
can maintain compliance with the requirements of Subpart EEE. The 
certification program (i.e., written examination at a minimum) would be 
required to address the topics in the training curriculum. The training 
curriculum would be required to include the following topics: (1) 
Environmental concerns, including types of emissions; (2) basic 
combustion principals, including products of combustion; (3) operation 
of the specific type of combustor used by the operator, including 
proper startup, waste firing, and shutdown procedures; (4) combustion 
controls and continuous monitoring systems; (5) operation of air 
pollution control equipment and factors affecting performance; (6) 
inspection and maintenance of the combustor, continuous monitoring 
systems, and air pollution control devices; (7) actions to correct 
malfunctions or conditions that may lead to malfunctions; (8) residue 
characteristics and handling procedures; and (9) applicable Federal, 
state, and local regulations, including Occupational Safety and Health 
Administration workplace standards. This training curriculum is modeled 
after the requirements the Agency recently promulgated for commercial 
and industrial solid waste incinerators. See 65 FR 75338 (December 1, 
2000). We believe this training is also appropriate for hazardous waste 
combustors.
    To maintain certification, an operator would be required to 
complete an annual review or refresher course covering, at a minimum, 
the following topics: (1) Update of regulations; (2) combustor 
operation, including startup and shutdown procedures, waste firing, and 
residue handling; (3) inspection and maintenance; (4) responses to 
malfunctions or conditions that may lead to malfunction; and (5) 
operating problems encountered by the operator. These are the same 
requirements the Agency recently promulgated for commercial and 
industrial solid waste incinerators at Sec. 60.2085, and we believe 
they are also appropriate for hazardous waste combustors.

C. Control Room Operator Training and Certification Would Not Be 
Required for Shift Supervisors

    The final rule requires the same level of training and 
certification for shift supervisors and control room operators. 
Incinerator stakeholders question whether shift supervisors need to 
meet these training and certification requirements. Stakeholders note 
that shift supervisors often have administrative duties that are not 
closely related to the technical knowledge required to operate and 
maintain a combustor.
    After reconsideration, we agree with stakeholders' reasons for not 
requiring that shift supervisors be trained and certified to the level 
of a control room operator. Accordingly, we propose to require that 
shift supervisors, like personnel other than control room operators, be 
trained and certified to the technical level commensurate with the 
employee's job duties.

D. A Certified Control Room Operator Must Be on Duty At All Times

    We propose to revise the rule to clarify that a certified control 
room operator must be on duty at the source at all times the source is 
in operation. Having a certified operator present at all times is 
necessary to ensure compliance with the emission standards and 
operating requirements, and to take appropriate corrective measures 
when malfunctions occur.

VI. Bag Leak Detection System

    Section 63.1206(c)(7)(ii) of the hazardous waste combustor rule 
prescribes baghouse operation and maintenance requirements for 
incinerators and lightweight aggregate kilns, including a requirement 
for the continuous operation of a bag leak detection system as a 
continuous monitor. Since promulgation of the rule, stakeholders have 
raised two issues: (1) Can less sensitive bag leak detectors be 
approved under the alternative monitoring provisions; and (2) why did 
we conclude that opacity monitors meeting revised Performance 
Specification 1 are not likely to be acceptable bag leak detectors.

A. Can Less Sensitive Bag Leak Detectors Be Approved Under the 
Alternative Monitoring Provisions?

    Section 63.1206(c)(7)(ii)(D)(1) requires the bag leak detector 
system to be capable of continuously detecting and recording mass 
changes in particulate matter emissions at concentrations of 1.0 
milligrams per actual cubic meter or less. Stakeholders state that 
monitors with higher detection limits are able to detect subtle changes 
in baseline, normal emissions as well as catastrophic events, and 
question whether these monitors can be approved under the alternative 
monitoring petitioning procedures of Sec. 63.1209(g)(1).
    We support the use of monitors with higher detection limits 
provided the monitor is sensitive enough to detect subtle increases in 
baseline, normal emissions, and we plan to develop guidance 
recommendations on this issue. We request comment on whether 
Sec. 63.1206(c)(7)(ii)(D)(1) should be revised to explicitly allow the 
use of monitors with higher detection limits, or whether the existing 
alternative monitoring provisions coupled with guidance recommendations 
is sufficient. In addition, we request comment on how a source would 
document that a bag leak detection system, with a detection level 
higher than 1.0 milligrams per actual cubic meter, can detect subtle 
changes in baseline, normal mass emissions of particulate matter. For 
example, should we require site-specific tests to document that 
alternative detectors provide a measurable and repeatable change in 
opacity output with an increase in particulate matter mass emissions?

B. Why Did We Conclude That Opacity Monitors Meeting Revised 
Performance Specification 1 Are Not Likely To Be Acceptable Bag Leak 
Detectors?

    EPA promulgated a significantly improved Performance Specification 
1 (PS1) for opacity monitors on August 10, 2000. See 65 FR at 48914. We 
considered whether to allow use of

[[Page 35135]]

opacity monitors meeting PS1 as bag leak detectors, but conclude that 
they are not likely to be sensitive enough to detect subtle increases 
in mass particulate matter emissions from a source equipped with a well 
designed and operated baghouse.
    Revised PS1 includes additional design and performance 
specifications as well as new test procedures that provide a profound 
improvement on opacity data accuracy and precision. Collectively, the 
additional measures provide a comprehensive, in-depth functional test 
of the complete measurement procedure, thereby eliminating many of the 
performance problems associated with previous opacity monitors.
    The revisions go far beyond the previous version of PS1, drawing on 
recent technological advancements in optics, electronics, and 
information transfer. There are similar specifications for such 
monitors in Europe. The stipulation of automatic self-diagnosing 
capability is one of the many modern features incorporated into the new 
PS1. Taken together, the additional measures reflect a distinct new 
generation in the state-of-the-art of opacity monitors.
    Notwithstanding the improvements that revised PS1 requires, opacity 
monitors are generally not acceptable for use as a bag leak detector 
because they are not sensitive enough to detect subtle increases in 
baseline, normal emissions. Baghouse emission opacity levels are very 
nearly zero at particulate matter concentrations below emission 
standards and are very near the lower detection limits of a continuous 
opacity monitoring system (COMS). COMS manufacturers have collectively 
raised the concern about COMS sensitivity limitations at low opacity 
levels. (See ASTM D-6216-98, Standard Practices for Opacity Monitor 
Manufacturers to Certify Conformance with Design and Performance 
Specifications.) Although the increase in particulate matter mass 
emissions that would trigger a measurable opacity change that a COMS 
could detect is usually site-specific and would depend on the particle 
size and reflective and refractive properties. We are concerned that 
particulate matter emission concentrations may have to double or triple 
before a COMS could detect a significant opacity change at the low 
opacity levels associated with baghouse emissions. For these reasons, 
we conclude that COMS meeting Performance Specification 1 are not 
likely to be suitable as bag leak detectors. Nonetheless, as discussed 
above, we request comment on whether an approach could be developed to 
allow use of bag leak detectors that have detection limits above 1.0 
milligrams per actual cubic meter.
    Moreover, we note that electrodynamic and triboelectric bag leak 
detectors have proven to be much more sensitive and cost about the same 
or less than COMS to install and operate. In addition, some particulate 
matter continuous emissions monitors (CEMS) have been shown to be able 
to detect very small changes in particulate matter mass emissions at 
low emission levels. If sources were to use a particulate matter CEMS 
as a bag leak detector, sources need not correlate the detector to 
particulate matter emission concentrations. Rather, sources would be 
required to document that the CEMS provides a measurable and repeatable 
change in output with an increase in particulate matter mass emissions.

VII. Time Extensions For Performance Testing if the Test Plan Has 
Not Been Approved

    During the comment period of the final rule and after promulgation, 
stakeholders raised the concern that the rule requires sources to 
commence performance testing within 180 days after September 30, 2002, 
even if the test plan has not been approved. Although the rule requires 
submittal of the test plan 12 months prior to the scheduled test date 
to provide a nine-month review period, stakeholders are concerned that 
the test plan may not be approved at the conclusion of that review 
period. Stakeholders state that they may spend hundreds of thousands of 
dollars to conduct a test under an unapproved test plan, only to learn 
after the test that EPA or the state may not accept the results as a 
valid demonstration of compliance with the emission standards due to 
differences of opinion on test design. In the preamble to the final 
rule, we address this issue by stating that ``If permit officials 
nevertheless fail to act within the nine-month review and approval 
period, a source could argue that this failure is tacit approval of the 
plan and that later ``second-guessing'' is not allowable.'' See 64 FR 
at 52912. However, stakeholders are concerned that this preamble 
language does not guarantee that they will not have to repeat the test. 
Stakeholders recommend revising the rule to allow sources to wait until 
a test plan has been approved before conducting a performance test.
    We are reluctant to deviate from the Part 63 General Provision's 
six-month deadline after the compliance date for conducting the initial 
comprehensive performance test. We continue to believe that an open-
ended test date will not provide an incentive for either sources or 
regulatory officials to resolve differences related to a test plan, 
thereby unnecessarily delaying testing. Nonetheless, we acknowledge 
that there may be situations where a source and regulatory officials 
are making genuine efforts to complete review of the test plan, but for 
reasons beyond their control, the review cannot be completed prior to 
the testing deadline. Accordingly, we propose to revise the rule to 
address these particular situations.
    Under today's proposal, a source may petition the Administrator, 
under the authority of Sec. 63.7(h), to obtain a ``waiver'' of any 
performance test--initial or periodic performance test; comprehensive 
or confirmatory test. The ``waiver'' would not eliminate the test, but 
would be used to grant an extension of time to conduct the performance 
test. To qualify for the waiver, a source must make a good faith effort 
to comply with the testing requirements in a timely manner. First, as 
currently required, sources must submit a site-specific emissions 
testing plan and a continuous monitoring system performance evaluation 
test plan at least one year before a comprehensive performance test is 
scheduled to begin (see Sec. 63.1207(c)(1)), or at least 60 days before 
a confirmatory performance test is scheduled to begin (see 
Sec. 63.1207(d)). Sources also must submit all other documentation 
required by Subpart EEE to be included with the performance test plans. 
The submitted test plans must fulfill the substantive content 
requirements of Secs. 63.1207(f) and 63.8(e). Second, a source must 
make a good faith effort to accommodate the Administrator's comments on 
the test plans. Finally, the Administrator must not take final action, 
through a notification of intent to deny (see Sec. 63.7(c)(3)(i)(B)), 
to deny the source's test plan(s).
    Under today's proposal, sources must submit to the Administrator a 
waiver petition or request to renew the petition under Sec. 63.7(h), 
separately for each source, at least 60 days prior to the scheduled 
date of the performance test. The Administrator would approve or deny 
the petition within 30 days of receipt and promptly notify the source 
of the decision. The Administrator would not approve extensions of the 
test date for a duration exceeding 6 months, and the Administrator 
would include in granted petitions a sunset provision to end the waiver 
within 6 months.
    To renew a waiver, we are proposing that sources must submit a 
revised petition under Sec. 63.7(h)(3)(iii) at least 60 days prior to 
the end date of the most recently approved waiver petition. The 
Administrator could approve a revised

[[Page 35136]]

petition for a total waiver period up to 12 months. A performance test 
could not be delayed more than a total of 12 months, irrespective of 
the status of approval of the test plan.
    If the Administrator denies a Sec. 63.7(h) waiver petition, we are 
proposing that the source must commence the performance test, with or 
without approved test plans, by either the deadline provided by Subpart 
EEE or by the expiration date of their most recently approved waiver 
petition, whichever is later.
    Sources would also need to address, in the waiver petition, the 
following requirements of Sec. 63.7(h). A source must provide 
documentation to enable the Administrator to determine if ``the source 
is meeting the relevant standard(s) on a continuous basis * * *.'' See 
Sec. 63.7(h)(2). For extension requests of the initial comprehensive 
performance test, a source must submit the Documentation of Compliance 
to assist the Administrator in making this determination. In addition, 
Sec. 63.7(h)(3)(iii) requires sources to ``include information 
justifying the owner or operator's request for a waiver, such as the 
technical or economic infeasibility, or the impracticality, of the 
affected source performing the required test.''
    In order to continue to keep the public informed of the source's 
compliance status, the source would need to notify the public (i.e., 
the source's public mailing list) of their Sec. 63.7(h) petition to 
``waive'' a performance test.
    The following is an example time line indicating how the proposed 
Sec. 63.7(h) waiver petitioning process would work for the initial 
comprehensive performance test. All end dates should be read as ``no 
later than'' X number of months. The time line assumes the source has 
submitted its performance test plans (i.e., for emissions testing and 
continuous monitoring system evaluation) on the deadline date--one year 
before the performance test must be conducted (i.e., sources submit the 
test plans 6 months prior to the compliance date).

0 time--Submittal of performance test plans for review (1 year prior to 
test date; 6 months prior to compliance date).
9 months--Administrator does not approve or deny test plans, even 
though the source has acted in good faith to obtain approval
10 months--Submittal of performance test waiver petition and notify 
public (2 months prior to test date).
11 months--Administrator approves or denies the performance test waiver 
(1 month after receipt of waiver).
12 months--Commence performance test if the Administrator denies 
waiver.
12 months + 6months--Extended performance test commencement 
date if the Administrator approves waiver.
16 months--If needed, submit performance test waiver renewal petition 
and notify public (2 months prior to sunset of latest approved waiver).
17 months--Administrator approves or denies renewal petition (1 month 
after receipt of renewal petition).
18 months--Maximum extension of test date for unrenewed performance 
test waivers.
18 months + 6months--Extended performance test commencement 
date with renewed waiver.
24 months--Maximum extension of test date for renewed performance test 
waivers.

VIII. Flexibility in Operations During Confirmatory Performance 
Testing for Dioxin/Furan

    During the confirmatory performance test, the final rule requires 
sources to operate so that carbon monoxide or hydrocarbon levels, and 
operating parameter limits associated with the dioxin/furan emission 
standard, are within the range of the average values over the previous 
12 months. Sources also must stay within the maximum or minimum value, 
as appropriate, that is allowed. See Sec. 63.1207(g)(2). These 
requirements ensure that during the confirmatory performance test, 
dioxin/furan emissions are within the range of the normal to the 
highest allowable emissions.
    Stakeholders express concern that it may be difficult to ``dial 
in'' operation of the combustor to the required range for each 
operating parameter simultaneously. Sources are particularly concerned 
about having to operate within a potentially narrow range of carbon 
monoxide levels for sources that normally operate close to the 100 ppmv 
limit. This is because carbon monoxide levels are dependent on many 
combustion-related factors and cannot be directly ``dialed in'' as can 
be done for other parameters (e.g., activated carbon injection 
federate).
    Although this is not likely to be a widespread problem, we 
acknowledge there may be a problem in some situations. Accordingly, we 
propose today to revise the rule to: (1) Allow approval in the test 
plan for operations under a wider operating range for a particular 
parameter based on information justifying that operating within the 
required range may be problematic; and (2) allow the Administrator to 
accept test results during the finding of compliance based on 
operations outside of the range specified in the confirmatory test 
plan.
    Allowing the Administrator to accept test results based on 
operations outside of the range specified in the test plan would 
address when a source did not anticipate a problem in maintaining the 
operating levels within the required range (and therefore did not 
request advance approval to do so), but because of unforeseen factors, 
were unable to maintain the required range. This provision would give 
permit writers discretion to accept emissions data obtained when 
operating outside of the prescribed range so that sources would not 
have to incur the costs of an additional confirmatory test. In 
determining whether to accept test results from operations outside of 
the range specified in the test plan, permit writers would consider 
factors including: (1) The magnitude and duration of the deviation from 
the required range; (2) the historical range of the parameter (e.g., 
the range between the 10th and 90th percentile time-weighted average 
values for the parameter); (3) the proximity of the emission test 
results to the standard; and (4) the reason for not maintaining the 
required range. These factors determine whether the operations are 
reasonably representative of normal operations and how important it may 
be that test operations be truly representative of normal operations.

IX. Waiving Operating Parameter Limits During Performance Testing

    Section 63.1207(h) automatically waives the operating parameter 
limits (OPLs) during subsequent comprehensive performance tests under 
an approved performance test plan. After promulgation, stakeholders 
raised two concerns. They believe that: (1) OPLs defined in the 
Documentation of Compliance should be waived during the initial 
comprehensive performance test and associated pretesting; and (2) OPLs 
should be waived during testing and pretesting irrespective of whether 
the test plan has been approved.

A. Should We Waive OPLs During the Initial Comprehensive Performance 
Test?

    Section 63.1211(d) requires sources to include in the operating 
record a Documentation of Compliance (DOC) that establishes limits on 
the operating parameters under Sec. 63.1209 that, based

[[Page 35137]]

on an engineering evaluation, will ensure compliance with the emission 
standards. The DOC may be revised at any time prior to submitting the 
Notification of Compliance. If additional engineering information 
becomes available that leads sources to conclude that they can operate 
under less stringent OPLs during the initial comprehensive performance 
test and demonstrate compliance with the emission standards, the DOC 
may be revised accordingly. Therefore, we do not believe that 
additional regulatory language is needed to enable source to operate 
during pretesting or the initial comprehensive performance test under 
OPLs less stringent than those identified in the DOC. We specifically 
request comment on this issue.

B. Should We Allow the OPLs To Be Waived if the Test Plan Has Not Been 
Approved?

    Section 63.1207(h) waives the OPLs during performance testing under 
an approved test plan. We required pretesting and testing operations to 
be conducted under an approved test plan as a prerequisite for the 
waiver. This will ensure that operations, when the OPLs are waived, are 
likely to remain in compliance with the emission standards. In 
retrospect, however, we acknowledge that stack emissions measurements 
will be taken during both pretesting (see Sec. 63.1207(h)(2)) and 
testing. Given that there will be documentation of any exceedance of an 
emissions standard during a performance test, potentially indicating a 
violation during such testing, it is not necessary to require that the 
test plan be approved before the OPLs can be waived. Similarly, if a 
source records the results of pretesting, the OPLs should be waived 
without approval of the test plan. Accordingly, we propose to revise 
the rule to waive the OPLs during pretesting (if the source records the 
results of the pretest) and performance testing. See proposed 
Sec. 63.1207(h).
    Although stakeholders have raised concerns about testing under an 
unapproved test plan (see Section VII above), there may be instances 
where a source may choose to test under such conditions. Consequently, 
the regulatory revision appears to be warranted.

X. Method 23 as an Alternative to Method 0023A for Dioxin/Furans

    The final rule requires use of Method 0023A to determine compliance 
with the dioxin and furan emission standard. See Sec. 63.1208(b)(1). 
Based on discussions with stakeholders after promulgation of the final 
rule, we believe it is appropriate to request comment on amending the 
final rule to allow petitions for the use of Method 23 in lieu of 
Method 0023A.\15\
---------------------------------------------------------------------------

    \15\ Sources can currently petition EPA to use alternative test 
methods pursuant to Sec. 63.7(f). The petition process that we are 
requesting comment on would not require sources to submit the 
results of a Method 301 validation process as is required under 
Sec. 63.7(f).
---------------------------------------------------------------------------

    Method 23 is the Clean Air Act dioxin/furan air emission test 
method found in 40 CFR Part 60, Appendix A. Method 0023A is the RCRA 
dioxin/furan air emission test method found in SW-846.\16\ The final 
rule requires use of Method 0023A because this method is the updated 
version of Method 23. At the time of final rule publication, we 
believed that the improvements to the updated method warranted use of 
Method 0023A.
---------------------------------------------------------------------------

    \16\ Method 0023A was proposed on July 25, 1995 (see 60 FR 
37974). EPA received comments on Method 0023A and later incorporated 
the method into SW 846 in a final rule on June 13, 1997 (see 62 FR 
at 32451).
---------------------------------------------------------------------------

    Stakeholders request that we give sources the option to use Method 
23 or Method 0023A because: (1) The dioxin/furan standard is based on 
emissions data that was collected using Method 23 procedures; (2) 
Method 0023A is more expensive because of additional analytical costs; 
and (3) Method 0023A results in higher detection limits.
    Method 23 and Method 0023A are similar methods. Method 23 combines 
the front half of the filter and probe rinse with the back half of the 
sorbent and rinses to perform a single extraction and analysis. 
Recovery of spiked standards into the sorbent are used to serve as an 
indicator of overall recovery. Method 0023A differs from Method 23, 
primarily in that Method 0023A uses the addition of standards to both 
the filter (front half) and sorbent (back half), and then separates the 
front half and back half for analysis in order to determine the 
recovery from each half. They are separated in order to better quantify 
recoveries for both the back half and front half fractions. This is 
important, because low recoveries in Method 23 are sometimes associated 
with dioxin/furan contained in solid phase particulate that may go 
unnoticed due to the combined front half and back half analysis. This 
may be of particular importance for sources that use activated carbon 
injection, or sources whose particulate matter contains significant 
levels of carbonaceous material. In other words, Method 0023A was 
designed as an improvement to Method 23 by incorporating separate 
recovery, spiking, and analysis of front half and back half samples to 
improve the quality assurance of the front half and back half analysis. 
The benefits of Method 0023A compared to Method 23 include accurate 
recovery data and known data quality. The downsides to Method 0023A 
include higher analytical costs and possibly higher detection limits.
    Although the detection limits of Method 0023A may be higher than 
Method 23 detection limits, we do not believe that these higher 
detection limits will adversely affect a source's ability to adequately 
demonstrate compliance with the dioxin/furan standard, as we explained 
in the technical support document to the final rule.\17\ This is true 
because analytical detection limits have decreased over recent years.
---------------------------------------------------------------------------

    \17\ See ``Final Technical Support Document for HWC Standards, 
Volume IV: Compliance with HWC MACT Standards,'' Chapter 16, July 
1999.
---------------------------------------------------------------------------

    We request comment on whether we should amend the final rule to 
give the option to use Method 23 in lieu of Method 0023A. We are 
considering allowing sources to petition the authorized regulatory 
agency to use Method 23 in lieu of Method 0023A. Under such an 
approach, a source would have to justify why the use of Method 23 is 
warranted. Factors that could be considered by the regulatory official 
in reviewing these petitions include: (1) The carbonaceous content of 
the particulate that is emitted from the source; (2) analytical costs; 
(3) data quality; and (4) detection limits. For example, under this 
approach, we believe that a source could address Method 23 data quality 
concerns by submitting previous Method 0023A results to the regulatory 
official that document: (1) The recovery percentages of the front and 
back half of the analysis; and (2) the amount of dioxin and furans 
present in the front half. Method 0023A results that indicate good 
front half recoveries could support a source's claim that Method 23 is 
an appropriate method to demonstrate compliance with the dioxin/furan 
emission standard.\18\ The added data quality checks associated with 
Method 0023A may not be needed if the results of previous Method 0023A 
analyses indicate good front half recovery percentages. Method 23 may 
also be warranted if dioxin and furans are not detected, or are 
detected at low levels in the front half of Method 0023A.
---------------------------------------------------------------------------

    \18\ This assumes, however, that method recoveries do not 
significantly vary at a source for different emissions tests. Any 
petition to use Method 23 should address whether method recoveries 
are expected to change from one emission test to another.

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

[[Page 35138]]

XI. Calibration Requirements for Thermocouples

    Section 63.1209(b)(2)(i) of the final rule requires verification of 
the calibration of each thermocouple or other temperature sensor at 
least once every three months. Stakeholders express concern that 
recalibration of each temperature measurement device every three months 
is a significant undertaking. Stakeholders explain that, for example, 
temperature measurement devices on the air pollution control train are 
typically flanged onto the process piping and/or vessels. To 
recalibrate these devices without shutting the combustor down is an 
involved process. Removing these measurement devices for recalibration 
would require the operator to enter a static value in the automatic 
waste feed cutoff system to avoid a cutoff, and have a technician 
equipped with appropriate personal protective equipment receive the 
appropriate line and equipment opening permits, and then try to safely 
remove the instrument from the process while the combustor is still 
running. For configurations that have pressurized portions of the air 
pollution control train, the combustor would be required to shut down 
to avoid release of fugitive emissions. Stakeholders question whether 
the benefits outweigh the burden of recalibrating each temperature 
device every three months.
    Stakeholders also state that recalibration of pyrometers is 
particularly problematic. Optical pyrometers are often sealed at the 
factory to prevent adjustment of the calibration. To check calibration 
on an optical pyrometer is difficult and stakeholders believe it is not 
a task that should be undertaken every three months unless there are 
clear benefits.
    It is not clear to us that recalibration of all types of 
temperature measurement devices every three months is as burdensome an 
undertaking as stakeholders suggest. Thermocouples are the most common 
temperature measurement device used for compliance assurance. We 
believe that their calibration can generally be confirmed without 
removing them from the combustor. Thermocouples may malfunction either 
by a failure in the circuit (e.g., the junction between the two wires 
at the bead may break) or the electronics may drift. If the circuit 
fails, the thermocouple will give clearly erroneous readings. Drift in 
the electronics can be corrected without removing the thermocouple. We 
specifically request comment on whether thermocouples can be 
recalibrated without removing them from the combustor.
    Although it may be impractical to calibrate the internal operations 
of a pyrometer every three months, as stakeholders suggest, there are 
other maintenance activities such as cleaning of the optics and 
alignment checks that will help ensure that the pyrometer is performing 
correctly. We specifically request comment on whether the rule should 
require that these and other maintenance activities should be performed 
every three months.
    If based on review of comments to this notice and reevaluation we 
determine that recalibration of temperature monitoring devices every 
three months is not practicable, we would revise the rule to delete 
Sec. 63.1209(b)(2)(i). In lieu of a generic recalibration requirement 
that applies to all temperature monitors, we would require that you 
develop an appropriate calibration procedure and frequency and include 
that information in the evaluation plan required by Sec. 63.8(e)(3)(i).

XII. Alternative Approach To Establish Operating Parameter Limits

    The rule requires sources to establish most operating parameter 
limits as the average of the test run averages of the comprehensive 
performance test. Each test run average is calculated by summing all 
the one-minute readings within the test run and dividing that sum by 
the number of one-minute readings. See 64 FR at 52922.
    Stakeholders state that this is an unreasonably conservative 
approach to establish operating parameter limits in that sources would 
not be allowed to operate in the way that they did 50% of the time 
during the performance test (when demonstrating compliance with the 
emission standards). This may overstate the conservatism inherent in 
this approach.\19\ Nevertheless, we believe that a conservative 
approach is warranted because: (1) These parameters can have a 
significant effect on emissions; and (2) the approach is consistent 
with how manual method emissions results are determined (i.e., manual 
method emission test results for each run represent average emissions 
over the entire run).\20\
---------------------------------------------------------------------------

    \19\ For example, if the duration of each run of the performance 
test were 60 minutes, establishing parameter limits based on the 
average of the run averages allow sources to continue to operate as 
during the performance test. This is because 1-minute values that 
are higher than the average would be off-set by 1-minute values that 
are correspondingly lower than the average. Because most performance 
test runs have a duration longer than 60 minutes, however, the 
``average of the run averages'' approach coupled with an hourly 
rolling average averaging period for most parameter limits, will 
require that sources operate more conservatively than during the 
performance test as a practical matter.
    \20\ Petitioners in litigation challenging the underlying rule 
have maintained that the one-hour averaging time to demonstrate 
compliance with the dioxin standard effectively amends the standard. 
The argument goes that the one-hour averaging period is shorter than 
that used in the source's performance test. EPA disagrees; the 
dioxin standard does not prescribe any particular averaging time, or 
other monitoring regime, for achieving a temperature level, so that 
using a one-hour averaging time does not amend the standard. 
However, even if (against our view) the temperature monitoring 
requirement is considered to change the emission standard, it 
appears justifiable as a beyond the floor standard under CAA section 
112(d)(2). First, the standard is readily achievable technically. 
Spray quenching, the means of control, merely requires turning of a 
control valve to allow quenching. USEPA, ``Final Technical Support 
Document for Hazardous Waste Combustor MACT Standards, Volume IV: 
Compliance with the Hazardous Waste Combustor Standards,'' July 
1999, p. 2-16. Operators can readily determine when quenching is 
needed, since thermocouples report instantaneous temperature 
changes, allowing immediate reaction to temperature changes. Ibid, 
p. 2-10. Second, EPA has already considered this cost (i.e., the 
cost of quenching) in determining the standards for HWCs. EPA does 
not believe that there would be any incremental cost associated with 
the one-hour averaging requirement, because it is based on the same 
spray quenching technology which is the basis for the standards 
already adopted. See also 64 FR at 52892 (finding that the cost of 
spray quenching technology for lightweight aggregate kilns is 
reasonable, in adopting the beyond-the-floor standard for dioxin/
furans). In addition, the one-hour averaging requirement is needed 
to prevent exceedances of the emission standard itself, see Ibid, at 
2-8 to 2-9 and 3-8 to 3-9 (documenting how net dioxin/furan 
emissions would increase over the amounts allowed by the emission 
standard without this requirement, but further explaining why the 
ten-minute averaging time that EPA initially proposed is not 
essential). See also EPA's Brief in CKRC v. EPA, no. 99-1457 (D.C. 
Cir. 2001) at pp. 113-120 (a copy of this brief is part of the 
record for this proposal). Finally, we do not believe there are any 
adverse non-air or energy impacts associated with the averaging 
requirement (and again, EPA has already assessed energy impacts and 
waste generation impacts of the standard when promulgating the 
standard in the first place). See generally USEPA, ``Final Technical 
Support Document for Hazardous Waste Combustor MACT Standards, 
Volume V: ``Emissions Estimates and Engineering Costs,'' July 1999 
(RC2F-S0011) chapter 10.
---------------------------------------------------------------------------

    Stakeholders also maintain that it is not technically practicable 
to establish some operating parameter limits using the average of the 
test run averages. Stakeholders present examples including cement kiln 
minimum combustion chamber temperature (see discussion in Section XIV 
below), and secondary power input to an ionizing wet scrubber or wet 
electrostatic precipitator.
    In light of stakeholders' concerns, we are considering an 
alternative approach to establish operating parameter limits that 
provides assurance of compliance with the emission standard: 
establishing multiple limits for a given parameter that ensures that 
the profile of the

[[Page 35139]]

parameter does not exceed the profile documented during the 
comprehensive performance test. We call this the ``matching-the-
profile'' approach.
    Under the matching-the-profile approach, a source would establish 
multiple limits for a given parameter that ensure that the profile of 
the parameter does not exceed the profile documented during the 
comprehensive performance test. This approach has the advantage of 
allowing operations at parameter levels above the average level of the 
performance test for the same period of time and at the same levels, as 
shown during the performance test. Provided that the source operates 
below the average level of the performance test for the same period of 
time, and at the same levels, as during the performance test. One 
disadvantage is that, to effectively implement the approach, sources 
would be required to establish multiple operating limits for a single 
parameter.
    As an example of how this matching-the-profile approach would work 
for establishing the gas temperature operating limit at the inlet to an 
electrostatic precipitator, consider the following hypothetical gas 
temperature data for three runs of a comprehensive performance test. 
The individual run times are presented, and the total of the run times 
is nine hours.

Table 1.--Alternative Approach To Establish an OPL Whereby the Parameter Profile Documented During the Comprehensive Performance Test Cannot Be Exceeded
                                              [Example Parameter: Gas temperature at the inlet to an ESP.]
               [Assume Run Times as Follows: Run 1-180 minutes; Run 2-150 minutes; Run 3-210 minutes. Total time of 540 minutes (9 hrs).]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                   1-Min avg temperature that was not exceeded the specified %                         Time that avg run
                                                                         of Time ( deg.F)                           Average of run        avg can be
                 Percent of time                 ---------------------------------------------------------------       averages       exceeded in any 9-
                                                         Run 1                Run 2                Run 3                                   hr block
--------------------------------------------------------------------------------------------------------------------------------------------------------
100% (max T)....................................                 405                  415                  425                  415                0 min
90%.............................................                 395                  398                  390                  394               54 min
50%.............................................                 375                  380                  375                  377              270 min
25%.............................................                 370                  350                  360                  360              405 min
--------------------------------------------------------------------------------------------------------------------------------------------------------

    In this example, we have assumed that four operating limits would 
be needed to ensure adequately that the performance test profile is not 
exceeded: a maximum temperature that could not be exceeded, and three 
temperature limits that could be exceeded for prescribed periods of 
time during each 9-hour block average. In practice, the number of 
parameter limits would be established on a site-specific basis and 
would be a function of factors including: (1) The variability of the 
parameter during the test (i.e., range from the high to low value 
\21\); (2) whether the performance test emission levels were close to 
or well below the emission standard; and (3) the relationship between 
the parameter and emission levels. \22\
---------------------------------------------------------------------------

    \21\ The greater the range of values for a parameter within a 
percentile, the less certain we can be that the performance test 
profile (and emission levels) will be maintained. This is because a 
source could theoretically operate for extended periods of time 
(i.e., longer than during the performance test) at the upper end of 
the range (or the lower end for parameters for which minimum limits 
are established).
    \22\ For example, more rather than fewer parameter limits would 
be appropriate to characterize the profile for gas temperature at 
the inlet to an electrostatic precipitator given that dioxin/furan 
emissions relate exponentially to inlet gas temperature.
---------------------------------------------------------------------------

    In the example presented above, 1-minute average temperature levels 
are ranked from highest to lowest for each run, and the temperature 
associated with various time percentiles (i.e., 100%, 90%, 50%, and 
25%) are identified. In Run 1, for example, temperatures below 
395 deg.F were achieved 90% of the time. Then, a time-weighted average 
temperature across the runs is calculated for each of the percentiles. 
Finally, the time percentiles are converted to the number of minutes in 
a block period of time (corresponding to the time required to conduct 
all runs of the performance test). We now have a series of temperature 
limits that can be exceeded only for a specified period of time. 
Compliance with these time/temperature limits should ensure that the 
temperature profile of the performance test is not exceeded during 
normal operations, and that the emission standard is not exceeded.
    We request comment on whether this approach to establish operating 
parameter limits as an alternative to calculating the limit as the 
average of the test run averages would be less burdensome for regulated 
sources while ensuring compliance with the emission standards. We also 
note that sources can request alternative monitoring approaches under 
Sec. 63.1209(g)(1) and may request to use this (or other) alternative 
approach whether or not EPA finalizes this proposal. We request comment 
on whether we should explicitly include this approach in the rule, or 
use this discussion as guidance recommendations. Explicitly defining 
the approach in the rule may better facilitate efforts by sources to 
adopt the approach to their needs, and review and approval of the 
approach by regulatory officials.

XIII. Extrapolation of Operating Parameter Limits

    Stakeholders suggest that the rule inappropriately penalizes 
sources that achieve comprehensive performance test emission levels 
well below the standard by establishing operating parameter limits 
based on performance test operations at those low emission levels. 
Operating under conditions to artificially increase emissions during 
testing (e.g., by detuning emission control equipment) may not be 
feasible or desirable from a worker/public health and cost perspective.
    To address this concern, we request comment on whether the rule 
should allow extrapolation of an operating parameter limit \23\ 
established as currently required to a higher limit (or lower limit if 
the parameter limit is a minimum limit) using a site-specific, 
empirically-derived relationship between the parameter and emissions of 
the pollutant in question.\24\ An example is extrapolation of the gas 
temperature limit at the inlet to the dry particulate matter control 
device to a higher limit based on the relationship between gas 
temperature and dioxin/furan emissions. To use this approach, a source 
must document the relationship

[[Page 35140]]

empirically for their source. To remain in compliance with the emission 
standard, however, the temperature limit could be extrapolated to 
levels higher than 400  deg.F only if the extrapolated dioxin/furan 
emissions were below 0.2 ng TEQ/dscm.
---------------------------------------------------------------------------

    \23\ Requests to extrapolate metal feedrates would continue to 
be considered under Sec. 63.1209(n)(2)(ii).
    \24\ In addition to using site-specific, empirically-derived 
relationships, we also request comment on whether the rule should 
allow use of established engineering principles that define the 
relationship between operating parameters and emissions to 
extrapolate operating limits and emissions.
---------------------------------------------------------------------------

    Sources could not take advantage of this extrapolated gas 
temperature limit in this example without also extrapolating the gas 
temperature limit for compliance assurance with the semivolatile and 
low volatile metals standards.\25\ This is because gas inlet 
temperature is a compliance parameter for both dioxin/furans and 
semivolatile and low volatile metals. We would also consider allowing 
extrapolation of the metals compliance assurance inlet gas temperature 
limit using engineering calculations to a temperature limit that would 
correspond to metals levels close to the emission standards.
---------------------------------------------------------------------------

    \25\ A gas inlet temperature limit is not required, however, if 
the source feeds low levels of metals and complies with the 
semivolatile and low volatile metals standards without emissions 
testing by documenting compliance with the emissions standards 
assuming all metals that are fed are emitted. In addition, even if 
the source were required to comply with a lower gas temperature 
limit for compliance assurance for metals, there may still be 
advantages to establishing an extrapolated temperature limit for 
compliance with the dioxin/furan standard. For example, if the 
source had a performance test-based temperature limit (i.e., metals 
temperature limit) exceedance that did not exceed the extrapolated 
dioxin/furan-based limit, the temperature exceedance would not 
represent failure to maintain compliance with the dioxin/furan 
emission standard.
---------------------------------------------------------------------------

    We believe that extrapolated limits should be less than 100% of the 
standard. Such conservatism is important because sources would not have 
actually demonstrated compliance with the emission standards at the 
extrapolated operating parameter limit. We request comment on what 
upper level of extrapolation would be appropriate (e.g., 75%, 80%) and 
whether the upper level of extrapolation should vary depending on the 
level of confidence in the empirical relationship or other approach 
that is used to calculate the extrapolation.
    The Administrator would grant (or deny) a petition to extrapolate 
an operating parameter limit on a case-by-case basis considering 
factors including whether: (1) The operating parameter values during 
the performance test were at the upper (or lower for minimum limits) 
range of historical, normal levels; (2) the extrapolated level sources 
request is warranted considering historical levels of the parameter; 
(3) it is impracticable to demonstrate compliance with the emission 
standard when operating at the desired (i.e., extrapolated) operating 
limit during the performance test; and (4) the extrapolation procedure 
will conservatively predict the relationship between the operating 
parameter and emissions. To determine if the extrapolation procedure 
conservatively relates the operating parameter to emissions, the 
Administrator would consider factors including how far the source 
requests to extrapolate the limit beyond the value calculated from the 
performance test and how close the emissions during the performance 
test were to the standard.
    We also note that sources can request alternative monitoring 
approaches under Sec. 63.1209(g)(1) and may request to use this (or 
other) alternative approach prior to promulgation of a final rule. We 
request comment on whether we should explicitly include this approach 
in the rule, or use this discussion as guidance recommendations. 
Explicitly defining the approach in the rule may better facilitate 
efforts by sources to adopt the approach to their needs, and review and 
approval of the approach by regulatory officials.

XIV. Limit on Minimum Combustion Chamber Temperature for Cement 
Kilns

    Stakeholders have expressed concern that it is technically 
impracticable for cement kilns to establish a minimum combustion 
chamber temperature based on the average of the test run averages for 
each run of the comprehensive performance test. Stakeholders state that 
combustion chamber temperatures cannot be maintained at low enough 
levels for the duration of the comprehensive performance test to 
establish workable operating limits that would allow them to burn 
hazardous waste fuels economically without frequent waste feed cutoffs 
because of potential exceedences of the limit. Stakeholders indicate 
that combustion chamber temperature levels are fairly constant within a 
narrow range and note that there is a very narrow range of temperatures 
and feed composition in which a cement kiln must operate in order to 
produce quality clinker and a marketable product.
    Stakeholders further note that they must take extreme actions under 
the current RCRA requirements to establish an economically viable 
minimum combustion chamber limit based on the average of the lowest 
hourly rolling averages for each run. Stakeholders relate that during 
one hour of each run of the RCRA compliance test, they must take 
unusual and potentially equipment-damaging steps to lower temperatures. 
\26\ Those problems are compounded by the requirement in the MACT rule 
to establish the limit based on the average temperature level.
---------------------------------------------------------------------------

    \26\ We note that allowing sources to establish operating limits 
under current RCRA regulations based on the average minimum or 
maximum hourly rolling average (rather than the average of the 
average values as required under Subpart EEE) is intended to address 
routine deviations that can occur even though steady-state operating 
conditions are maintained. Modifying operating conditions during 
compliance testing to induce temporary, artificial perturbations is 
inappropriate. Such operations are not representative of operations 
under the test condition.
---------------------------------------------------------------------------

    In addition, stakeholders note that it is difficult to accurately 
monitor combustion chamber temperature in a cement kiln. We already 
acknowledge this concern and, accordingly, the rule allows measurement 
of the temperature at a location that best represents, as practicable, 
the bulk gas temperature in the combustion zone. See 
Sec. 63.1209(j)(1)(i). The rule also allows sources to petition the 
permit writer to request approval of an alternative temperature 
monitoring approach. See Sec. 63.1209(g)(1).
    We have responded, in the final rule Comment Response Document, to 
stakeholder's questions about the need for monitoring combustion 
chamber temperature by noting that combustion chamber temperature is a 
principal factor in ensuring combustion efficiency and destruction of 
toxic organic compounds. Although we acknowledge that a cement kiln 
inherently controls the kiln temperature to produce clinker, this 
inherent control may not be adequate to assure compliance with the 
dioxin/furan and destruction and removal efficiency emission standards. 
For example, we understand that cement kilns occasionally undergo 
upsets and produce substandard clinker. If lower than normal combustion 
chamber temperatures can result from an upset, we do not know how 
compliance with the emission standards can be assured.
    Notwithstanding these reservations, and in light of stakeholders' 
continued concerns, we request comment on whether the rule should 
continue to require cement kilns to establish and comply with a minimum 
combustion chamber temperature limit. Stakeholders have indicated that 
they have produced additional data supporting their views. We also 
request comment on whether the alternative approaches discussed above 
which can be used to establish alternative operating parameter limits 
(i.e., match-the-profile and extrapolation) would address some of 
stakeholders' concerns with establishing a minimum

[[Page 35141]]

combustion chamber temperature limit for cement kilns. We note, again, 
that sources may use Sec. 63.1209(g)(1) to request alternative 
monitoring approaches and need not wait for the Agency's final 
determinations subsequent to this notice.

XV. Revisions to Operating Requirements for Activated Carbon 
Injection and Carbon Bed Systems

    The final rule requires sources using carbon beds or activated 
carbon injection systems to limit particulate matter emissions to the 
level achieved during the comprehensive performance test. See 
Secs. 63.1209(k)(5) and 63.1209(l)(3). We have since determined that: 
(1) It is inappropriate to explicitly require a site-specific 
particulate matter limit if a carbon injection system is used; and (2) 
particulate matter control downstream of a carbon bed is not a critical 
operating parameter to ensure compliance with the dioxin/furan and 
mercury emission standards. We propose, therefore, to delete the site-
specific particulate matter limit requirement for activated carbon 
injection systems. We also propose to delete the requirement for 
sources equipped with carbon beds to establish particulate matter 
operating parameter limits to ensure compliance with the dioxin/furan 
and mercury emission standards.
    Dioxin/furan and mercury will adhere to the solid carbon used in an 
activated carbon injection systems. The final rule requires a site-
specific particulate matter limit for this type of control system 
because an increase in particulate matter emissions could also 
correspond to an increase in dioxin/furan and mercury emissions. After 
considering stakeholder comments, we believe it is inappropriate to 
explicitly require a site-specific particulate matter limit if a carbon 
injection system is used because the rule does not require continuous 
monitoring of particulate matter emissions with a continuous emission 
monitor. The use of a site-specific particulate matter limit was 
originally thought to go in tandem with the requirement to use 
particulate matter CEMS. Since we do not require sources to use 
particulate matter CEMS for compliance purposes, we believe it is 
inappropriate to require site-specific particulate matter limits.\27\ 
Particulate matter emissions are instead controlled by complying with 
operating limits on the particulate matter control devices (e.g., 
minimum power to an electrostatic precipitator). Therefore, we propose 
to revise Sec. 63.1209(k)(5) to require sources to establish operating 
limits on the particulate matter control device consistent with the 
approach used to control particulate emissions for compliance assurance 
with the semivolatile and low volatile metals emission standards.
---------------------------------------------------------------------------

    \27\ The issue of the use of site-specific particulate matter 
limits to assure compliance with metal and dioxin/furan standards, 
when sources use a particulate matter CEM, will likely be addressed 
in any future particulate matter CEM proposal.
---------------------------------------------------------------------------

    We also believe that particulate matter control downstream of a 
carbon bed is not a critical operating parameter to ensure compliance 
with the dioxin/furan and mercury emission standards. We note that 
most, if not all, carbon bed systems in use today are positioned 
downstream from particulate matter control devices to minimize 
particulate buildup in the carbon bed. Carbon beds are also designed so 
that carbon leakage into the flue gas is minimized.\28\ We, therefore, 
propose to delete the language in Sec. 63.1209(k)(5) that requires 
control of particulate matter emissions to ensure compliance with the 
dioxin/furan and mercury standards for sources with a carbon bed.
---------------------------------------------------------------------------

    \28\ See memo from S. Schliesser to M. Galbraith, June 7, 2000, 
regarding ``Carbon Bed Reentrainment Issue'' for more information.
---------------------------------------------------------------------------

XVI. Clarification of Requirements to Confirm Carbon Bed Age

    When demonstrating compliance with the dioxin/furan (and mercury) 
emission standard during the initial comprehensive performance test, 
sources may use the manufacturer's specification for the limit on 
carbon bed age rather than the actual age of the bed during the 
performance test. If using the manufacturer's specification for carbon 
bed age, Sec. 63.1209(k)(7)(i)(C) requires sources to recommend in the 
initial comprehensive performance test plan a schedule for subsequent 
dioxin/furan emissions testing, prior to the confirmatory performance 
test, that will be used to document to the Administrator that the 
initial limit on maximum bed age ensures compliance with the dioxin/
furan emission standard.
    Stakeholders express several concerns with these requirements: (1) 
How much testing and what type of testing is required to confirm bed 
life; (2) if the manufacturer's specification for bed life is such that 
it extends beyond the deadline to conduct the dioxin/furan confirmatory 
test, testing to confirm bed life should not be required before that 
dioxin/furan confirmatory test; and (3) given that a carbon bed 
controls mercury as well as dioxin/furan, testing to confirm bed life 
should be required to demonstrate compliance with both the dioxin/furan 
and mercury emission standards. We address each of these issues below.

A. How Much Testing and What Type of Testing Is Required to Confirm Bed 
Life?

    We intended that testing equivalent to the dioxin/furan 
confirmatory test would be required to confirm the life of the carbon 
bed. Therefore, a test comprised of at least three runs would be 
required. The operating conditions would be the same as required for 
the dioxin/furan confirmatory test under Sec. 63.1207(g)(2).\29\
---------------------------------------------------------------------------

    \29\ Given that carbon bed removal efficiency is closely related 
to combustion gas temperature at the inlet to the bed system, we 
request comment on whether the carbon bed life confirmatory test 
should be conducted at inlet gas temperatures at or near the maximum 
allowed (i.e., rather than at levels within the range of normal 
levels to the maximum allowed).
---------------------------------------------------------------------------

B. What Happens If Bed Life Extends Beyond the Deadline for Dioxin/
Furan Confirmatory Testing?

    If the manufacturer's specification calls for a bed life beyond the 
deadline for confirmatory testing, the source must conduct the dioxin/
furan confirmatory test by the deadline and also conduct the bed life 
confirmatory test at any time prior to the manufacturer's specification 
for bed life. We are proposing to revise the rule so that in this 
situation bed life confirmatory testing would not be required prior to 
dioxin/furan confirmatory testing.
    If, for example, the manufacturer's specification for bed life was 
3.5 years and the bed was installed just prior to the comprehensive 
performance test, the source must conduct the dioxin/furan confirmatory 
test within 2.5 years after the comprehensive performance test. In 
addition, the source must conduct a bed life confirmatory test within 
3.5 years of the comprehensive performance test. Of course, sources may 
elect to forgo the additional year of bed life to avoid the expense of 
conducting the carbon bed life confirmatory test.

C. Should Bed Life Confirmatory Testing Include Testing To Confirm 
Compliance With Both the Dioxin/Furan and Mercury Emission Standards?

    Given that carbon beds control both dioxin/furan and mercury 
emissions, bed life confirmatory testing must document compliance with 
both the dioxin/furan and mercury emissions standards. Not requiring 
mercury testing during bed life confirmatory testing was an oversight 
when we promulgated the rule. We are proposing to revise the rule 
accordingly. See proposed revision to Sec. 63.1209(l)(4).

[[Page 35142]]

    The bed life confirmatory testing for mercury must be conducted 
under normal conditions for the operating parameters used to control 
mercury emissions. See Sec. 63.1209(l). This is the same concept that 
is used to confirm bed life for dioxins/furans, and for the dioxin/
furan confirmatory test. Thus, the parameters specified under 
Sec. 63.1209(l) must be held within the range of the average value over 
the previous 12 months and the maximum or minimum, as appropriate, that 
is allowed.

XVII. Revisions to Operating Parameter Limits for Wet Scrubbers

    The final rule controls mercury emissions from hazardous waste 
combustors by: (1) Controlling the feedrate of mercury; (2) wet 
scrubbing to remove soluble mercury (e.g., mercuric chloride); and (3) 
carbon adsorption. See Sec. 63.1209(l). There are specific operating 
parameter limits that apply to each control technology.
    For hazardous waste combustors using wet scrubbers to control 
mercury, the operating parameter limits are identical to those that are 
required to assure compliance with the hydrochloric acid/chlorine gas 
emission standard. Specifically, those requirements include 
establishing hourly rolling average limits on minimum pH of the 
scrubber water based on operations during the comprehensive performance 
test. The hourly rolling average is established as the average of the 
test run averages. The pH of the scrubber water is an important 
parameter for chlorine control because, at low pH, the scrubber 
solution is more acidic and removal efficiency of hydrochloric acid and 
chlorine gas decreases.

A. What Is the Issue With the Minimum Operating Parameter Limit 
Requirement for Wet Scrubbers With Regard to Mercury Control?

    Since promulgation of the rule, we've become aware of evidence that 
the scrubber liquid pH can have an important effect on the control and 
fate of mercury in wet scrubbers. In particular, various wet scrubber 
manufacturers and operators have observed that low pH (acidic) scrubber 
liquid solutions improve the control of mercury in hazardous waste 
combustor stack gases. There also is some recent work supporting the 
idea that scrubber liquid pH is an important factor in mercury capture 
and removal. In addition to low pH liquids increasing the control of 
elemental mercury, there's also evidence that high pH liquids may tend 
to reduce the captured soluble mercury back to the elemental form of 
mercury, which would then be re-released with the liquid during the 
liquid recycle. This line of thinking suggests that it may be necessary 
to establish a maximum scrubber liquid pH during the compliance test to 
ensure sufficient mercury control. However, a maximum scrubber liquid 
pH is opposite to the minimum liquid pH limit that is set and used to 
control chlorine emissions.

B. How Would a Low pH Scrubber Liquid Improve Mercury Control?

    There are a number of reasons why a low pH scrubber liquid is 
thought to improve mercury control:
    --Most elemental mercury formed in combustion is thought to favor 
conversion (or oxidation) to ionic mercury, such as HgCl2, 
mercuric chloride, under typical air pollution control device 
conditions on hazardous and other waste combustors (e.g., see Lee and 
Kilgroe (1998), Hall (1991)).
    --Oxidized mercury is very soluble in low pH scrubbing solutions 
(e.g., see Siret et al. (1997)). Also, strong reducing agents in 
scrubber liquid (which are more likely in higher pH scrubbing liquids) 
will reduce and revolatilize captured mercury.
    --Scrubber liquids with high pH (i.e., added NaOH) may inhibit the 
oxidation of elemental mercury, and its subsequent absorption into the 
scrubber liquid (i.e., the ability to be controlled by the scrubber), 
see Soelberg (1998).
    --In high pH reducing liquids, captured soluble ionic mercury may 
be reduced back to elemental forms in the scrubber liquid and then re-
released during the liquid during recycle. The use of low pH solutions 
minimizes this possibility by favoring the formation of stable 
HgCl4 (e.g., see Krivanek (1993)). Ionic mercury with a 
(Hg+2) oxidation state is very soluble in water, especially 
in low pH scrubbing solutions. This enables the mercury to be readily 
absorbed from the flue gases. Elemental mercury has a low solubility 
and would typically pass through a wet scrubbing system unabsorbed. 
Without some way to avoid mercury revolatilization, it has been 
observed that elemental mercury emissions downstream of a wet scrubber 
can actually be higher than the inlet loading (see Siret et al. (1997), 
DeVito and Rosenhoover (undated).
    Alternatively, there is some work on mercury control in coal fired 
utility power plants with limestone-based wet scrubbers indicating that 
changes in scrubber liquid pH in the range of 5 to 7 does not impact 
mercury control (see Miller, (undated), McDermott Technology 
(undated)). However, these data may not be directly applicable to the 
case of hazardous waste combustors due to the following: Basic scrubber 
liquids of pH greater than 7 were not evaluated; the use of limestone 
in these data, which is uncommon in hazardous waste combustor wet 
scrubbers; high levels of sulfur and lower levels of chlorine in coal 
stack gases; very low levels of mercury measured both upstream and 
downstream of the scrubber; and conflicting data on the predominant 
mercury species being emitted (whether it is elemental mercury or ionic 
mercury).

C. When Should a Maximum pH Limit Be Considered for Mercury Control?

    The use of a operating parameter limits on maximum scrubber liquid 
pH may be appropriate to ensure that mercury emissions are minimized. 
In particular, there are several cases where requiring this as an 
operating parameter limit for mercury control may be desirable when:
    --The scrubber is relied upon for achieving a certain mercury 
control efficiency in order to achieve the mercury emission standard.
    --The facility has a history of a wide range of mercury 
concentrations in the feed waste streams.
    --The facility has a history of a wide range of variations in 
scrubber liquid pH, oxidation potential, or composition.
    --There is a wide range of HCl, NOX, and SO2 
emission levels expected in the flue gas based on waste composition.

D. How Would We Set a Maximum pH Limit in the Scrubber Liquid?

    If it is determined to be necessary to achieve a high level of 
mercury control, it may be appropriate to establish both an upper and a 
lower pH operating range. The lower pH limit maybe set based on either 
(1) manufacturer/designer recommendations (which would have to be 
reviewed and approved by the Agency and contained in the performance 
test plan), or (2) with a separate compliance test required for 
determining the lower pH operating parameter limit for chlorine. At 
that time, an operating range could be specified which would also 
consider the upper end of pH allowable for the desired mercury control. 
If the wet scrubber is staged, or if two wet scrubbers are operated in 
series, it may be appropriate to establish during the same performance 
test, a maximum pH limit on one scrubber for mercury control and a 
minimum pH limit on the other scrubber for chlorine control.
    If a ``total species'' mercury continuous emissions monitor is 
used, then no monitoring of operating

[[Page 35143]]

parameters related to mercury is required. However, if only an 
elemental mercury monitor is used, wet scrubber operating parameters 
may also need to be monitored.

E. What Are Other Factors Affecting a Wet Scrubber's Ability to Control 
Mercury?

    In addition to pH, there are a number of factors affecting the wet 
scrubber's ability to control mercury. For instance, it is well 
documented that the oxidizing potential of the scrubber solution has a 
direct impact on the control of elemental mercury. The recent use of 
scrubber liquid oxidizing additives such as NaClO2, 
acidified KMnO3, Na2S, and Cl2 has 
been shown to enhance elemental mercury control. Other factors 
influencing mercury control include: scrubber design, chloride 
concentration, mercury concentration and speciation at the inlet to the 
scrubber, and the use of special reagents (as mentioned above) to 
chemically convert and capture some of the elemental mercury.

F. What Are the Agency's Options To Ensure That the Scrubber Liquid pH 
Is Appropriate for Mercury Control?

    We request comment on requiring sources with wet scrubbers to 
establish a maximum pH operating parameter limit for mercury control. 
This maximum pH level could be based on manufacturer specifications, 
compliance test results, or specified by the permit writer on a case-
by-case basis. Another option is to require a scrubber liquid oxidation 
meter be used to comply with a minimum liquid oxidation potential 
limit. If chlorine is a concern, a pH range could be specified, or, as 
mentioned earlier, if two scrubbers are used, one could have a maximum 
pH specified for mercury control and a minimum pH specified for 
chlorine control.

XVIII. Reproposal of kVA Limits for Electrostatic Precipitators and 
Request for Comment on Approaches To Ensure Baghouse Performance

    The final rule establishes operating parameter limits for 
electrostatic precipitators (ESPs) and baghouses: (1) Minimum kVA per 
field of an ESP; and (2) minimum and maximum pressure drop (delta P or 
dP) for each cell of a baghouse. See Sec. 63.1209(m)(1)(ii and iii). At 
EPA's request, however, the D.C. Circuit has vacated these provisions 
in order that EPA repropose and seek additional comment on them. See 66 
FR 24270. Today, we repropose the requirement to establish minimum 
limits on each field of an ESP and request comment on alternative 
approaches to ensure such performance. For baghouses, we request 
comment on alternative approaches to ensure performance.

A. Requirements To Ensure Electrostatic Precipitator Performance

    Stakeholders express concern that limiting the kVA to each field of 
an electrostatic precipitator is problematic because: (1) It precludes 
the flexibility to shut down one or more fields of a multi-field 
electrostatic precipitator for maintenance while continuing hazardous 
waste burning; (2) it is difficult to establish minimum kVA limits on 
each field of the ESP during the comprehensive performance test that 
provide a wide enough operating envelop for economical operations; and 
(3) kVA to the first few fields of a multi-field ESP are not that 
important and should not be limited.
    We respond to these concerns by noting that power distribution 
across the fields of an ESP is very important to performance. EPA 
testing at a cement kiln showed that individual field power level 
distribution was critical to performance.\30\ When power input to the 
last field of a four-field ESP was decreased while total power input 
was held constant (i.e., by slightly increasing the power to the second 
and third fields), emissions of particulate matter doubled from 0.06 to 
0.12 gr/dscf. In addition, recent comparisons of the results from 
predictive emission models to actual emissions indicate that power 
input by field is an important refinement to the code predictions.
---------------------------------------------------------------------------

    \30\ See memorandum from Bruce Springsteen, EER-GC, to Bob 
Holloway, US EPA, entitled ``Relationship Between PM Emissions and 
ESP Total kVA Vs Field kVA'', dated November 21, 2000.
---------------------------------------------------------------------------

    Furthermore, we do not believe that limits on kVA to each field of 
the ESP are as burdensome as stakeholders state. For example, we do not 
believe it is a common problem to have a situation where a single field 
is down for repair and, thus, not operating at its minimum kVA, while 
the ESP is kept on line. Generally, when an ESP field needs repair, the 
ESP is taken off line. In addition, the comprehensive performance test 
may be structured to provide operational flexibility as needed. For 
example, a source seeking flexibility to continue burning hazardous 
waste with one field down could conduct the performance test under that 
mode of operation. Alternatively, the source could simulate the 
operational flexibility during the comprehensive performance test. For 
example, the source could conduct each run of the performance test with 
all fields operational 90% of the time, and with one field down 10% of 
the time. Then, the source would need to limit the time of operation 
with one field down to 10% of each block period of time (i.e., block 
average) equivalent to the time required to conduct the performance 
test.
    Finally, another remedy may be to use the authority of 
Sec. 63.1209(g)(1) to petition the permit writer for an alternative 
monitoring approach to ensure performance of the ESP is maintained.
    Given that we believe that power distribution across the ESP is 
important to ensure performance and that minimum limits on power input 
to each field would not be overly burdensome, we today repropose the 
kVA limits originally promulgated at Sec. 63.1209(m)(1)(iii).
    Notwithstanding this proposal, however, we request comment on 
several alternatives to limiting kVA to each field of the ESP (which 
may ultimately serve as alternatives which can be pursued under 
Sec. 63.1209(g)(1)), as discussed below. Note that several of these 
alternatives are not mutually exclusive. After considering comments and 
further evaluation, we also may decide to promulgate several 
alternatives.
1. Require an Increasing KVA Pattern Across the ESP
    Under this approach, sources would be required to establish a 
minimum limit on total kVA to the ESP based on the performance test, 
and to assure that kVA levels increase from the inlet to outlet fields. 
In addition, we would require establishment of a minimum limit on total 
kVA to the ESP.
    Maintaining a minimum total kVA with a pattern of progressively 
increasing kVA from the inlet fields to the outlet field is generally a 
good indicator that the entire ESP, as well as each field, is 
performing adequately. The rationale for this approach is that the 
power suppression effect from high particle concentrations 
progressively diminishes from the inlet field to the outlet field. 
Implementation of this approach would mean that the actual kVA levels 
for each field, or the absolute or relative difference in kVA from 
field to field that was achieved during the performance test, would not 
be considered in compliance assurance.
2. Limit KVA on Only the Back \1/3\ of Fields
    This approach would require establishment of minimum kVA to each of 
the last \1/3\ of the fields in the ESP, as well as a minimum limit on 
total kVA

[[Page 35144]]

to the ESP based on the performance test.\31\ The rationale for this 
approach has a similar basis to the approach in paragraph 1, but with 
an altered interpretation. Given that high particle concentration 
suppresses ESP power levels, the outlet fields can only achieve high 
power levels when the inlet fields are performing adequately. If the 
inlet fields are not performing well (as well as during the performance 
test), then the minimum kVA on the last few fields cannot be 
maintained.
---------------------------------------------------------------------------

    \31\ Stakeholders also suggest another approach whereby limits 
would be established on minimum total kVA to the ESP, and minimum 
kVA only to the last field of the ESP. We request comment on this 
alternative approach as well.
---------------------------------------------------------------------------

    Under this approach, if the source has a 2 or 3-field ESP, they 
would establish a minimum kVA limit on the last field. If it's a 4, 5, 
or 6-field ESP, then establish minimum kVA limits on the last 2 fields. 
If it's a 7, 8, or 9-field ESP, then establish minimum kVA limits on 
the last 3 fields.
3. Use a Continuous Monitor That Measures Relative Particulate Matter 
Loadings
    Under this approach, sources would use a continuous monitor that 
can detect relative particulate matter loadings. The device must be 
sensitive enough to detect subtle increases in baseline, normal 
emissions. The monitor could be a baghouse leak detector, an opacity 
monitor, or a particulate matter continuous emissions monitoring 
system. Given that the source would be continuously monitoring relative 
particulate matter emissions under this approach, they would not need 
to establish kVA limits on the ESP.
    To implement this approach, the source would establish an operating 
parameter limit that is based on the response from the continuous 
monitor during the comprehensive performance test. In addition, we 
would require interconnection of the limit to the automatic waste feed 
cutoff system. The source would also be required to take corrective 
measures as prescribed in the operations and maintenance plan if there 
was an increase in the baseline, normal response (i.e., generally well 
below the response during the performance test). This would be similar 
to how a bag leak detector is used to ensure that performance of a 
baghouse is maintained.
4. Use of Predictive Emission Monitoring Systems
    This approach would use one of the available ESP performance models 
to characterize and correlate ESP performance with particulate matter 
emissions as a predictive emission monitoring system (PEMS). There are 
three personal-computer models (Electric Power Research Institute, EPA, 
and Southern Research Institute) that use the same first-principle 
equations. These models attest to using field-by-field electrical data, 
or similarly derived approaches, for compliance assurance. In 
combination with particulate matter measurements, each of these models 
has produced results with correlation coefficients greater than 0.98. 
Once adequately demonstrated to predict emissions, the model results 
would then serve as a compliance monitoring protocol able to account 
for any combination of power distribution levels and other contributing 
factors. If a source were to use this PEMS approach, they would have 
the flexibility to operate with a field out of operation and without 
the need for limits on field or total kVA while giving regulatory 
officials a means for ensuring compliance. This PEMS approach is based 
on a similar methodology advanced by industry that is undergoing review 
by EPA's Office of Air Quality Planning and Standards as a compliance 
assurance method (CAM).
    Implementation of the PEMS could follow a two-pronged procedure:
    a. Operations under the Green Zone. When particulate matter 
emissions are expected to be well below the particulate matter 
limit,\32\ referred to as the ``green zone,'' the source would use a 
secondary indicator (e.g., opacity) to monitor compliance. For example, 
the green zone could be defined as when the secondary indicator is 
below 75% of the level predicted by the model when operating at the 
particulate matter limit. There would be no need to apply the model 
when the secondary indicator (i.e., and therefore emissions) remains in 
the green zone.
---------------------------------------------------------------------------

    \32\ The particulate matter limit would be the PM emission 
standard or a lower PM emission level that is extrapolated from 
comprehensive performance test emission levels to a level that 
ensures compliance with the semivolatile and low volatile emission 
standards (and the dioxin/furan emission standards if sources use 
activated carbon injection). For example, if during the performance 
test the PM emissions were 50% of the PM standard, but the 
semivolatile metal emissions were 75% of the semivolatile metal 
standard, the source's PM compliance limit to ensure compliance with 
the semivolatile metal standard would be 75% of the particulate 
matter standard. This compliance assurance approach is based on the 
reasonable assumption that for a percentage increase in PM 
emissions, emissions of metals (and dioxin/furan when activated 
carbon injection is used) will increase by that percentage or less. 
This is because low volatile metals are evenly distributed over the 
range of PM particle sizes, while semivolatile metals and dioxin/
furan on adsorbed carbon, are enriched on the smaller particulates. 
As the performance of the PM control device degrades and PM 
emissions increase, some of the larger particles that were being 
captured would be emitted while the smaller particulates continue to 
be emitted as before.
---------------------------------------------------------------------------

    b. Operations under the Red Zone. When the secondary indicator 
value exceeds 75% of the level predicted by the model when operating at 
the particulate matter limit, the source would be in the ``red zone.'' 
During a red zone episode, they would apply the model at prescribed 
intervals (e.g., every 4 to 8 hours). Representative data (e.g., 
secondary voltage and current for each field, and gas temperature and 
flowrate) would be collected during the interval, averaged, and input 
to the model. Model results would predict the emission level and serve 
as the regulatory emission monitor for determining compliance. 
Depending on the model results, the source would respond appropriately.
    If the results indicate that the particulate matter limit has not 
been exceeded, the source would continue to operate. If the source were 
still in the red zone, they would either continue to apply the model at 
the prescribed interval, or perform corrective measures (e.g., 
remedying the ESP performance problem) to return to the green zone. If 
the model results indicate that emissions exceeded the PM limit, then 
the source has failed to comply with one or more of the emission 
standards.\33\
---------------------------------------------------------------------------

    \33\ For example, if the predicted emissions were higher than 
the PM standard and the extrapolated PM emission levels associated 
with the semivolatile and low volatile metal standards, as well as 
the dioxin/furan standard if sources use activated carbon injection, 
the model results would be evidence that the source has exceeded all 
four emission standards.
---------------------------------------------------------------------------

B. Requirements To Ensure Baghouse Performance

    The final rule required sources to establish limits on minimum and 
maximum pressure drop (delta P or dP) across each cell of the baghouse 
based on manufacturer specifications and to interconnect the limits 
with the automatic waste feed cutoff system. See 
Sec. 63.1209(m)(1)(ii). The rule also required incinerators and 
lightweight aggregate kilns to install a bag leak detector and cement 
kilns to install opacity monitors. As noted earlier, this provision was 
vacated by the D.C. Circuit at EPA's request so that EPA could 
repropose and seek further comment on the issue.
    We promulgated the requirement to establish dP limits because dP 
may provide an indication of adequate filter cake build-up to ensure 
performance. In addition, low dP may indicate the presence of filter 
holes or leakage between sections of the filter housing

[[Page 35145]]

while high dP may indicate the potential to create pinhole leaks, or 
bag blinding or plugging. We acknowledge, however, the minimum dP may 
not effectively detect fabric holes, especially in large facilities 
with multiple chamber filter housing units that operate in 
parallel.\34\
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    \34\ US EPA, ``Final Technical Support Document for Hazardous 
Waste Combustor MACT Standards, Volume IV: Compliance with the 
Hazardous Waste Combustor Standard,'' July 1999, p. 4-6.
---------------------------------------------------------------------------

    In addition, since promulgation of the rule, stakeholders state 
that system or manifold dP is the same as the dP for each cell or 
compartment. Therefore, monitoring dP for each cell is redundant and 
unnecessary. Stakeholders also state that baghouses for sources with 
large gas flowrates (e.g., a cement kiln) can have 30 or more cells and 
because of the large number of cells, establishing limits on, or even 
monitoring, dP is impracticable.
    Finally, stakeholders recently submitted data confirming our 
concern that cell dP is not sensitive to substantial increases in 
opacity for large baghouses.\35\ Stakeholders conducted experimentation 
at a cement kiln with a baghouse where dP was monitored for a cell in 
which collection performance was intentionally degraded. The baghouse 
has 32 cells and each cell is comprised of 56 bags. Prior to degrading 
the cell's performance, cell dP was monitored for several hours. The 
detector appeared to be responding appropriately to pressure changes as 
the pressure dropped to zero each time the cell was cleaned on a 25-
minute cycle and then rapidly increased to approximately 3.5 inches 
water column. The pressure then gradually increased to 4 to 5 inches 
water column prior to the next cleaning cycle. While performance of one 
cell was artificially degraded, opacity was also monitored. There was 
no discernable change in cell dP during the episode while opacity 
increased dramatically from baseline levels of 4 to 5 percent to 10 to 
12 percent. These opacity levels represent particulate matter emissions 
on the order of 0.01 gr/dscf at 5 percent opacity to 0.02 gr/dscf at 10 
to 12 percent opacity. Although this experiment indicates that dP is 
not always sensitive to significant changes in opacity, it also shows 
that an opacity monitor can detect significant changes in mass 
particulate matter emissions at concentrations in the 0.01 to 0.02 gr/
dscf range.
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    \35\ Data submitted by Norris Johnson, Lone Star Industries, 
Inc., to Bob Holloway, US EPA, on November 16, 2000.
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    We generally disagree with many of stakeholders' views on the value 
of monitoring cell dP. System or manifold dP is usually higher than 
cell dPs because of the dP contributed by plenums (including dust 
buildup) and compartment isolation valving. Many baghouses operate with 
uneven cell dP because of complex factors.\36\ For example, inlet flow 
design factors lead to gas flow imbalance among cells and to uneven 
cell dPs. Also, bag cleaning mechanisms degrade over time leading to 
varying levels of cleaning among cells and varying cell flow and dP. In 
addition, monitoring cell and system dPs is recommended by virtually 
all baghouse manufacturers and consultants because of the cost-
effectiveness in preventing small problems from escalating into large 
ones.
---------------------------------------------------------------------------

    \36\ See H.H. Nierman and A.M.Hood, ``How to Monitor Pulse Jet 
Baghouses,'' Chemical Engineering, March 1996, pp. 114-119
---------------------------------------------------------------------------

    We acknowledge again, however, that minimum cell dP may not 
effectively ensure performance of a large baghouse. Consequently, we 
are not reproposing limits on cell dP. Rather, we request comment on 
whether decisions to require monitoring of cell dP should be made on a 
site-specific basis (pursuant to Sec. 63.1209(g)(1) or (g)(2)) 
considering factors such as: (1) Whether the baghouse is equipped with 
a device (e.g., bag leak detector) that is properly tuned and has the 
sensitivity to detect both broken bags (i.e., emission spikes) and 
gradual increases in baseline, normal emissions that may be caused by 
small holes; and (2) the approach that would used to identify the 
poorly performing cell when the detector notes a gradual degradation in 
performance; and (3) size of the baghouse. In addition, in situations 
where commenters believe that monitoring cell dP should be required, we 
request comment on whether cell dP should be monitored as an operating 
parameter limit that is interconnected to the automatic waste feed 
cutoff system, or whether cell dP monitoring should simply be one 
component of the source's operation and maintenance plan (under which 
appropriate corrective measures would be taken if cell dP were to fall 
below or above manufacturer specifications).
    Pending final action on this notice, regulatory officials should 
use the authority of Sec. 673.1209(g)(2) to determine on a site-
specific basis what operating requirements may be appropriate to ensure 
that baghouse performance is maintained at levels that ensure 
compliance with the particulate matter, semivolatile metals, and low 
volatile metals emission standards (and the dioxin/furan and mercury 
standards if activated carbon injection is used).

XIX. How To Comply Temporarily with Alternative, Otherwise 
Applicable MACT Standards

    Section 63.1206(b)(1)(ii) allows sources to stop complying with the 
emission standards and operating requirements of Subpart EEE 
temporarily after the hazardous waste residence time has expired and to 
comply with otherwise applicable Clean Air Act requirements promulgated 
under Sections 112 and 129,\37\ provided the source: (1) Submits a one-
time notice to the Administrator documenting compliance with those 
alternative standards; \38\ and (2) documents in the operating record 
that they are complying with those alternative standards.
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    \37\ If the Agency has not promulgated CAA Section 112 or 129 
MACT standards for the non-hazardous waste burning class of sources 
in a particular source category, there are no ``otherwise 
applicable'' MACT standards for the source. For example, the Agency 
has not yet promulgated Section 129 standards for non-hazardous 
waste incinerators. In these cases, the source would not be subject 
to any MACT standards for stack emissions after the hazardous waste 
residence time has expired. The source must define such operations 
as a mode of operation under Sec. 63.1209(q), and must note in the 
operating record when they begin this mode of operation.
    \38\ Note that, in a separate rulemaking, EPA would delete the 
requirement for the one-time notification.
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    Stakeholders have asked how the transition between the Subpart EEE 
standards and the otherwise applicable Section 112 or 129 MACT 
standards would work. Specifically, stakeholders question: (1) whether 
sources would alternate as affected sources under different MACT 
standards for stack emissions, or become affected sources under 
different MACT standards concurrently; \39\ and (2) whether they should 
use Sec. 63.1209(q) to identify operations under the alternative 
Section 112 or 129 MACT standards as an alternative mode of operation.
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    \39\ For example, the hazardous waste burning cement kiln MACT 
standards of Part 63, Subpart EEE and the Portland Cement 
manufacturing MACT standards of Part 63, Subpart LLL.
---------------------------------------------------------------------------

A. Hazardous Waste Combustors Are Affected Sources Only Under Subpart 
EEE

    Even though sources may invoke Sec. 63.1206(b)(1)(ii) to become 
temporarily exempt from the substantive requirements of Subpart EEE, 
they remain an affected source under Subpart EEE, and only Subpart EEE 
(with respect to stack emissions requirements \40\), until the source 
meets

[[Page 35146]]

the requirements specified in Table 1 to Sec. 63.1200 for no longer 
being an affected source. Because those requirements include being in 
compliance with the RCRA closure requirements of Subpart G, Parts 264 
or 265, they remain an affected source until it is determined they no 
longer burn hazardous waste.
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    \40\ Note, however, that sources may be an affected source under 
different MACT standards concurrently for control of HAPs from 
different sources at the facility. For example, all hazardous waste 
burning cement kilns are affected sources under Subpart EEE for 
stack emissions, and Subpart LLL for other sources of HAP emissions 
(e.g., clinker handling).
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    To implement this clarification, we propose revising the rule to 
require that, if a source becomes temporarily exempt from the 
substantive requirements of Subpart EEE by halting hazardous waste 
burning activities, they must comply, during that temporary period, 
with all otherwise applicable Section 112 or 129 MACT standards. We use 
the term ``otherwise applicable'' because, after the hazardous waste 
residence time has expired, and if the source was not an affected 
source only under Subpart EEE, they would be subject to any and all 
Section 112 and 129 MACT standards we have promulgated for sources in 
the particular source category that do not burn hazardous waste (e.g., 
the MACT standards for Portland cement kilns in Part 63, Subpart LLL).
    In addition, we propose revising the rule to clarify that otherwise 
applicable Section 112 and 129 MACT standards are applicable 
requirements under Subpart EEE, if the source elects to comply with 
those requirements after the hazardous waste residence time has 
expired. This term has significant implications in that applicable 
requirements are implemented and enforced under Subpart EEE as 
discussed below.

B. How Are Otherwise Applicable Requirements Implemented and Enforced 
Under Subpart EEE

    Section 63.1209(q) requires establishment of operating requirements 
under different modes of operation. When electing to comply with the 
otherwise applicable MACT requirements (promulgated under Section 112 
or 129 of the CAA) after the hazardous waste residence time has 
transpired, the source must use Sec. 63.1209(q) to identify operating 
parameter limits that apply during that mode of operation. Section 
63.1209(q) also requires documentation in the operating record when 
changing a mode of operation and beginning to comply with a different 
set of operating limits. In addition, that paragraph requires sources 
to begin calculating rolling averages anew (i.e., without considering 
previous recordings) when changing modes of operation.
    Upon reevaluation of the requirement to begin calculating rolling 
averages anew when sources change modes of operation, we now believe 
that it would be more appropriate to use the most recent continuous 
monitoring system recordings when operating under a mode of operation 
to calculate rolling averages when renewing operations under that 
mode.\41\ For example, if operating a hazardous waste burning cement 
kiln and electing to switch to the Part 63, Subpart LLL, requirements 
after the hazardous waste residence time has expired, the first rolling 
hourly average value for gas temperature at the inlet to the 
electrostatic precipitator would be calculated after the first minute 
of compliance with the Subpart LLL requirements based on the last 59 
minutes of operations under the Subpart LLL requirements and the first 
minute of renewed operations under the Subpart LLL requirements. This 
would be the case regardless of how long ago the source last operated 
under the mode of operation in question.
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    \41\ Note, however, that may average operating parameter values 
continuously across various modes of operation provided that the 
averaging periods and limits for the parameter are the same under 
the various modes of operation.
---------------------------------------------------------------------------

    In the Documentation of Compliance (DOC) under Sec. 63.1211(d) and 
the Notification of Compliance (NOC) under Sec. 63.1207(j) the source 
must specify the operating parameter limits that apply when operating 
under the mode of operation when complying with otherwise applicable 
requirements.\42\ This requirement applies to all other modes of 
operation as well. For the mode of operation when complying with 
otherwise applicable requirements, however, the source must specify in 
the DOC and NOC any otherwise applicable Section 112 or 129 MACT 
standards and requirements that apply, including monitoring and 
compliance requirements and notification, reporting, and recordkeeping 
requirements. We limit this requirement to otherwise applicable Section 
112 or 129 MACT standards because the source may be subject to other 
Clean Air Act standards while being an affected source under Subpart 
EEE, but it is not an affected source under any Section 112 or 129 MACT 
standards other than Subpart EEE. Thus, the source would not be subject 
to any otherwise applicable Section 112 or 129 MACT requirements that 
were not included in the DOC, NOC, and, ultimately, title V permit for 
that mode of operation.
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    \42\ Furthermore, the title V permit must contain terms and 
conditions for all reasonably anticipated modes of operation (see 40 
CFR 70.6(a)(9)).
---------------------------------------------------------------------------

C. Exemption From All Substantive Requirements of Subpart EEE During 
the Mode of Operation When Complying With Otherwise Applicable Section 
112 or 129 MACT Standards

    Section 63.1206(b)(1) exempts sources from the emission standards 
and operating requirements of Subpart EEE when operating under 
otherwise applicable Section 112 or 129 MACT standards after the 
hazardous waste residence time has expired. We propose to revise this 
requirement to exempt sources from all substantive Subpart EEE 
standards during this mode of operation such that the source would only 
be subject to the Sec. 63.1209(q) provisions that it specifies for this 
mode of operation. This is appropriate because, as discussed above, 
sources must specify under Sec. 63.1209(q) that, during this mode of 
operation, they will comply with all requirements of the otherwise 
applicable requirements of Section 112 or 129 MACT standards. 
Accordingly, we propose to exempt sources during this mode of operation 
from the emission standards of Secs. 63.1203-63.1205; the monitoring 
and compliance standards of Secs. 63.1206-63.1209, except the modes of 
operation requirements of Sec. 63.1209(q); and the notification, 
reporting, and recordkeeping requirements of Secs. 63.1210-63.1212.

XX. RCRA Permitting Requirements for Sources Entering the RCRA 
Process Post-Rule Promulgation

A. What Are We Proposing To Amend?

    We are proposing to amend the language in 40 CFR 270.19, 270.22, 
270.62, 270.66, 266.100, 265.340, and 264.340 regarding the 
applicability of those sections to hazardous waste burning 
incinerators, cement kilns and lightweight aggregate kilns. In 
particular, we want to clarify that any of these types of sources newly 
entering the RCRA permitting process or the hazardous waste burning 
universe after promulgation of the hazardous waste combustor MACT rule 
on September 30, 1999 are not subject to certain specified RCRA permit 
requirements, or to the RCRA combustor performance standards.
    Since we are revisiting these sections to clarify their 
applicability, we are taking this opportunity to clarify a point about 
the Notification of Compliance, as referenced in these sections. Under 
Sec. 63.1207(j), sources must postmark within 90 days of completing a 
comprehensive performance test an NOC documenting compliance or 
noncompliance with the emissions standards. We are clarifying that in

[[Page 35147]]

order for the part 270 requirements to no longer apply, the NOC must 
document compliance.
1. How Had We Changed Part 270 in the HWC Rule?
    In the final rule, we amended language in part 270 to accommodate 
the permit transition from RCRA to the CAA. In Sec. 270.19, we added 
new paragraph (e) and in Secs. 270.22, 270.62, and 270.66 we added 
similar language as introductory text (with slight variations in 270.22 
and 270.66 to specify cement kilns and lightweight aggregate kilns). In 
brief, the amended language in these sections said that once a source 
demonstrates compliance with the standards in 40 CFR part 63 subpart 
EEE, the requirements in the specified part 270 sections would no 
longer apply. In order to retain a procedural framework for any risk 
burns \43\ that might prove to be necessary under RCRA, we also 
included a provision allowing the Director to apply the provisions of 
those sections, on a case-by-case basis, for purposes of information 
collection in accordance with Secs. 270.10(k) and 270.32(b)(2).
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    \43\ A risk burn is any emissions testing performed for the 
purpose of collecting data for subsequent evaluation in a site-
specific risk assessment. The testing may occur in conjunction with 
a RCRA trial burn or MACT performance test, or the risk burn may 
consist of a completely separate test effort.
---------------------------------------------------------------------------

2. Why Do We Need To Revisit these Sections in Part 270?
    As they were written for the final rule, these sections will 
continue to apply until a source demonstrates compliance with the 
standards in 40 CFR part 63 subpart EEE. This approach makes sense for 
sources who were currently in the RCRA permitting process at the time 
we published the final rule. Our primary concern at that time was on 
the transition from the RCRA process to the CAA. Since sources do not 
have to complete performance testing until May 2003, it is appropriate 
for sources already in the RCRA permitting process to continue the 
combustor portions of the process, including the trial burn 
requirements. We did not want the new rule to result in unnecessarily 
delayed testing, particularly if the testing is needed to ensure 
performance and to generate data for a risk assessment. In the preamble 
to the final rule, we discussed how sources already in the process of 
obtaining a RCRA permit could be transitioned to a title V permits (see 
64 FR 52989, September 30, 1999). We identified some factors to be 
considered, as well as some examples to assist permit writers and 
facility owners or operators in developing a sound approach. We 
neglected to consider, however, what this approach would mean for new 
sources that did not exist at the time the final rule was promulgated.
    Under RCRA, new sources must obtain a permit (or permit 
modification) before they may start construction of a new unit. Since 
new sources subject to the final rule will not be able to demonstrate 
compliance with the part 63 standards until after the units are built 
and they conduct performance testing, the part 270 language as 
currently promulgated would force them to complete the entire RCRA 
permitting process (including combustion portions) beforehand. For new 
facilities, this means they would have to submit a trial burn plan with 
their RCRA permit application and also submit suggested conditions for 
the various phases of operation--start-up/shake-down, trial burn, post-
trial burn, and final operations. The permit writer would have to 
review this information and write conditions into the RCRA permit 
governing all phases of combustor operations.
    It is our intent that new sources subject to the HWC final rule not 
follow the traditional RCRA combustion permitting process. Although new 
sources still must obtain a RCRA permit (or permit modification) prior 
to construction, our intent was that the permit instead focus on the 
other RCRA requirements applicable to all units (i.e., general facility 
standards, corrective action, financial responsibility, and closure), 
any non-emissions related combustor-specific concerns (i.e., materials 
handling), and requirements related to other RCRA units on site. In 
addition, if the alternative to the particulate matter standard 
revisions proposed today are promulgated, incinerators that comply with 
these alternative requirements would need to have the RCRA particulate 
matter performance standard and related operating conditions included 
in their RCRA permits. Also, if the permit writer determines that 
additional risk-based conditions for the combustion unit are necessary 
to supplement the MACT requirements, those conditions will be part of 
the RCRA permit.\44\ We would not expect new sources to follow the RCRA 
requirements governing development and submittal of trial burn plans 
and setting of operating conditions for the various phases of 
operation, because these activities implement RCRA performance 
standards which are being replaced by the HWC NESHAP standards. We 
included requirements in the HWC NESHAP governing implementation of the 
MACT performance standards. For example, sources must submit 
performance test plans and must identify operating parameters that they 
anticipate will ensure compliance with the emission limits in their 
Documentation of Compliance. The CAA process, not RCRA, is the 
appropriate mechanism to ensure compliance with the MACT standards. 
Under the CAA permitting programs, these sources will be subject to New 
Source Review permits prior to construction as well as to title V 
operating permits which will incorporate the applicable requirements 
from the HWC NESHAP.\45\
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    \44\ We expect that, in most cases, any additional risk-based 
conditions imposed under RCRA omnibus authority will reside in RCRA 
permits. However, a state regulatory agency may choose to 
incorporate those conditions into the title V permit as a matter of 
convenience or as part of developing a multi-media permit. In this 
situation, the conditions would still remain under RCRA authority 
and the permit would have to be signed by all appropriate officials 
(unless the state has omnibus-type authority in its air statute).
    \45\ Only those sources that meet the definition of a major 
source under the New Source Review permitting program are subject to 
federal New Source Review permits. The definition of ``major'' 
within the context of New Source Review permitting is different from 
that used when establishing MACT standards. Therefore, a new source 
subject to the Phase I MACT standards may not be required to obtain 
a federal New Source Review permit prior to construction. However, 
since all states have minor New Source Review permitting programs, 
it is likely that the source would still have to obtain a minor New 
Source Review permit.
---------------------------------------------------------------------------

3. What Are We Proposing To Amend in Parts 264, 265, 266?
    In today's notice, we also propose to make conforming changes in 
parts 264, 265, and 266 for the above mentioned reasons. Specifically, 
we propose to revise 40 CFR 264.340(b), 265.340(b), and 266.100(b) to 
specify that hazardous waste burning incinerators, cement kilns, and 
lightweight aggregate kilns that are newly constructed, reconstructed, 
or modified such that they become affected sources following September 
30, 1999 are not subject to the RCRA combustor treatment standards 
(except as noted) of parts 264, 265, and 266.

Part Three: Analytical and Regulatory Requirements

I. Executive Order 12866

    Under Executive Order 12866, EPA must determine whether a 
regulatory action is significant and, therefore, subject to 
comprehensive review by the Office of Management and Budget (OMB), and 
the other provisions of the Executive Order. A significant

[[Page 35148]]

regulatory action is defined by the Order as one that may:
    --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;
    --Create a serious inconsistency or otherwise interfere with an 
action taken or planned by another agency;
    --Materially alter the budgetary impact of entitlements, grants, 
user fees, or loan programs or rights and obligations or recipients 
thereof; or
    --Raise novel legal or policy issues arising out of legal mandates, 
the President's priorities, or the principles set forth in Executive 
Order 12866.
    Pursuant to the terms of Executive Order 12866, it has been 
determined that this rule is a ``significant regulatory action'' 
because it may be considered significant under point four above: 
``Raise novel legal or policy issues arising out of legal mandates, the 
President's priorities, or the principles set forth in Executive Order 
12866.'' As such, this action was submitted to OMB for review. Changes 
made in response to OMB suggestions or recommendations will be 
documented in the public record.
    The aggregate annualized compliance costs for this rule, as 
proposed, are estimated to be less than $100 million. Furthermore, this 
proposed rule is not expected to 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. The benefits to human health and the 
environment resulting from today's proposed action have not been 
monetized but are deemed to be less than $100 million per year.
    We have prepared two economic support documents for this proposed 
action. These are: Assessment of Potential Costs, Benefits and Other 
Impacts NESHAP: Standards for Hazardous Air Pollutants for Hazardous 
Waste Combustors--Technical Amendments (Assessment), and, Regulatory 
Flexibility Screening Analysis (RFSA) For NESHAP: Standards for 
Hazardous Air Pollutants for Hazardous Waste Combustors--Technical 
Amendments. The Assessment addresses economic impacts of the twenty 
proposed amendments to the Phase I MACT final rule. The Assessment also 
briefly examines equity considerations and other impacts. The 
Regulatory Flexibility Screening Analysis (RFSA) briefly examines small 
entity impacts potentially resulting from this proposed action. This 
Part presents a summary of findings from the Assessment and the RFSA 
documents. The complete Assessment and RFSA documents are available in 
the RCRA docket established for this action. Interested readers are 
encouraged to read and comment on these documents.

A. Why Is This Proposed Rule Necessary?

    The environmental regulations promulgated by EPA seek to correct 
market failures through the internalization of negative environmental 
externalities. That is not the case with today's proposed rule. This 
action is necessary in order to clarify and improve compliance, 
testing, and monitoring requirements associated with the final rule 
NESHAP: Final Standards for Hazardous Air Pollutants for Hazardous 
Waste Combustors. See 64 FR 52828.

B. Were Non-Regulatory Alternatives First Considered?

    Section 1(b)(3) of Executive Order 12866 instructs Executive Branch 
Agencies to consider and assess available alternatives to direct 
regulation prior to making a determination for regulation. This 
regulatory determination assessment should be considered, ``to the 
extent permitted by law, and where applicable.'' The ultimate purpose 
of the regulatory determination assessment is to ensure that the most 
efficient tool, regulation, or other type of action is applied in 
meeting the targeted statutory objective(s).
    We have already employed education and outreach programs designed 
to accomplish the objectives of the amendments proposed in this rule. 
We believe that technical clarification and improved implementation 
efficiency will be best accomplished through a regulatory approach in 
order to fully accomplish our objectives.

C. What Regulatory Options Were Considered?

    For this action we considered the proposed regulatory approach for 
all the technical amendments as a group, or in some cases, for an 
amendment that was presented for comment only. We also considered the 
``no action'' option, which would result in zero cost impacts beyond 
the baseline established in the final rule.

D. What Are the Potential Costs or Cost Savings of This Proposed Rule?

    The twenty proposed amendments presented in today's action vary 
considerably in scope and substance. Nearly all of the amendments, 
however, are anticipated to result in minor to negligible incremental 
cost impacts (savings or increases) to both the regulated community and 
the Agency. Two or three of the amendments may result in more 
substantive cost impacts. These findings are briefly summarized below. 
The complete Assessment document presents a detailed review of our 
methodology, data, findings, and analytical limitations.
    Cost Savings:
    The amendments resulting in projected minor cost savings to the 
regulated community are generally associated with the increased 
compliance and administrative flexibility, technical clarifications, 
time extensions, and reduced monitoring/testing requirements. One 
amendment, however, may result in significant net incremental cost 
savings to the regulated community. Amendment number X (Method 23 as an 
Alternative to Method 0023A for Dioxin/Furans), is designed to provide 
flexibility in selection of test methods for dioxins and furans. To 
test for dioxins and furans under the CAA, Appendix A of 40 CFR Part 60 
prescribes Method 23. This method combines the front half of the filter 
and probe rinse with the back half of the sorbent and rinses to perform 
a single extraction and analysis. Recovery of spiked standards into the 
sorbent are used to serve as an indicator of overall recovery.
    Method 0023A is the RCRA dioxins/furans air emission test method 
found in SW-846 (incorporated within SW-846 in June, 1997). The updated 
Method 0023A differs from Method 23 primarily in that the former uses 
the addition of spike standards to both the filter (front half) and 
sorbent (back half), and then separates the front half and back half 
for analysis in order to determine the recovery from each half. While 
more expensive, this process helps to quantify recoveries more 
accurately for both the back half and front half fractions.
    The final rule requires sources to use Method 0023A. At that time 
we believed the improvements method 0023A offered over Method 23 
warranted a requirement that all sources use the new method. By 
incorporating separate recovery, spiking, and analysis of front half 
and back half samples the new method helps better quantify recoveries 
for both the back half and front half fractions thereby improving 
quality

[[Page 35149]]

assurance. The benefits of Method 0023A compared to Method 23 thus 
include more accurate recovery data and improved data quality. The 
downside to Method 0023A is its higher analytical cost and, possibly 
higher detection limits. Furthermore, we have not documented the 
potential magnitude of the incremental benefits of Method 0023A.
    We estimate that potentially significant cost savings may result 
from the reduced analytical expenses of using Method 23 as an 
alternative to Method 23A for dioxin/furans. The difference in unit 
cost between the methods is approximately $3,000 per source. Industry 
estimates indicate that about half of all facilities are likely to make 
use of this alternative. However, this test is only required to be 
performed every two and a half years. Based on these factors, we 
estimate total cost savings to the regulated community at about 
$102,600 per year.
    Cost Increases:
    There may be cost increases associated with some of the proposed 
amendments. Many of the amendments associated with potential cost 
increases, however, propose alternatives that a source may voluntarily 
choose to apply. Cost increases would occur to both the regulated 
community and the regulatory agency and/or states. Most of these cost 
increases are expected to be minor, resulting from development and 
submission of alternative plans and/or test data. There may also be 
some minor additional cost burdens associated with potential increases 
in violations.
    We estimate that five of the proposed amendments may result in 
measurable incremental cost burdens to industry and the regulatory 
agency. These amendments are projected to result in aggregate cost 
increases to industry of $199,300 per year. The government cost 
increase is estimated at $161,800 per year. Amendment V (Operator 
Training and Certification) is the single largest cost contributor to 
the cost increase for both industry and government. This amendment is 
projected to result in an aggregate incremental cost increase of nearly 
$154,000 to industry and $150,700 to the regulatory agency.
    We estimate a net cost increase of $258,500 per year from all 
proposed amendments for which we were able to developed quantified cost 
impact estimates. This cost impact estimate will marginally increase 
the total annual social cost projection of $50 to $63 million \46\ 
estimated for compliance with the final rule. We believe that our net 
cost impact (increase) estimate of $258,500 may be high because it was 
not feasible to quantify some of the potential cost savings that are 
likely to result from many of the proposed amendments. All cost impacts 
are dependant upon the regional enforcement regime.
---------------------------------------------------------------------------

    \46\ U.S. Environmental Protection Agency, Office of Solid 
Waste, Addendum to the Assessment of the Potential Costs, Benefits, 
and Other Impacts of the Hazardous Waste Combustion MACT Standards: 
Final Rule, July 23, 1999.
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II. Regulatory Flexibility Act (RFA), as amended by the Small 
Business Regualtory Enforcement Fairness Act of 1996 (SBREFA), 5 
USC 601 et. seq.

    The RFA generally requires an agency to prepare a regulatory 
flexibility analysis of any rule subject to notice and comment 
rulemaking requirements under the Administrative Procedure Act or any 
other statute, unless the agency certifies that the rule will not have 
a significant economic impact on a substantial number of small 
entities. Small entities include small businesses, small organizations, 
and small governmental jurisdictions.
    For purposes of assessing the impacts of today's proposed rule on 
small entities, a small entity is defined as: (1) A small business that 
has fewer than 750, or 500 employees per firm depending upon the SIC 
code the firm is primarily classified in; (2) a small governmental 
jurisdiction that is a government of a city, county, town, school 
district or special district with a population of less than 50,000; or 
(3) a small organization that is any not-for-profit enterprise which is 
independently owned and operated and is not dominant in its field.
    After considering the economic impacts of today's proposed rule on 
small entities, I certify that this action will not have a significant 
economic impact on a substantial number of small entities. We have 
determined that only amendment X (Method 23 as an Alternative to Method 
0023A for Dioxin/Furans) is likely to impact one or more of the six 
small hazardous waste combustors. Under our assumed worst-case scenario 
where the maximum cost impacts of this amendment ($102,600 savings) are 
attributed to only these six small sources, we find that no source 
would experience impacts beyond 0.48 percent of annual gross revenues 
\47\. This does not represent a significant economic impact.
---------------------------------------------------------------------------

    \47\ Based on July 1999 Assessment, we found that the smallest 
annual firm revenue associated with the six small facilities were 
$3.6 million. Dividing $102,600 by the six facilities results in 
$17,100 maximum impact per small facility. ($17,100/$3.6 million = 
0.48 percent).
---------------------------------------------------------------------------

     Although this proposed rule will not have a significant economic 
impact on a substantial number of small entities, we nonetheless tried 
to reduce the impact of this rule on small entities. Although not 
specifically directed toward small business outreach, we have met with 
industry representatives during the developmental phase and requested 
comment and suggestions on all aspects of this proposed rulemaking. No 
small business concerns were brought up by these industry 
representatives. We continue to be interested in the potential impacts 
of the proposed rule on small entities and welcome comments on issues 
related to such impacts.
    We have completed the analysis: Regulatory Flexibility Screening 
Analysis (RFSA) For NESHAP: Standards for Hazardous Air Pollutants for 
Hazardous Waste Combustors--Technical Amendments, in support of the 
proposed rule. This RFSA document is available for review in the docket 
established for today's action.

III. Executive Order 13045: ``Protection of Children From 
Environmental Health Risks and Safety Risks''

    ``Protection of Children from Environmental Health Risks and Safety 
Risks'' (62 FR 19885, April 23, 1997) applies to any rule that: (1) Is 
determined to be ``economically significant'' as defined under 
Executive Order 12866, and (2) concerns an environmental health or 
safety risk that EPA has reason to believe may have a disproportionate 
effect on children. If the regulatory action meets both criteria, the 
Agency must evaluate the environmental health or safety effects of the 
planned rule on children, and explain why the planned regulation is 
preferable to other potentially effective and reasonably feasible 
alternatives considered by the Agency. This proposed rule is not 
subject to the Executive Order because it is not economically 
significant as defined in Executive Order 12866. Furthermore, we do not 
have reason to believe that environmental health or safety risks 
addressed by this action present a disproportionate risk to children.
    In addition, these amendments, as part of the HWC MACT standards, 
are exempt from the requirements of Executive Order 13045 because the 
rule is a technology-based regulation rather than a risk-based one. 
Nevertheless, the proposed amendments would not result in any 
incremental environmental harm that would affect children's health.

[[Page 35150]]

IV. Environmental Justice Executive Order 12898

    Executive Order 12898, ``Federal Actions to Address Environmental 
Justice in Minority Populations and Low-Income Population'' (February 
11, 1994), is designed to address the environmental and human health 
conditions of minority and low-income populations. EPA is committed to 
addressing environmental justice concerns and has assumed a leadership 
role in environmental justice initiatives to enhance environmental 
quality for all citizens of the United States. The Agency's goals are 
to ensure that no segment of the population, regardless of race, color, 
national origin, income, or net worth bears disproportionately high and 
adverse human health and environmental impacts as a result of EPA's 
policies, programs, and activities. In response to Executive Order 
12898, and to concerns voiced by many groups outside the Agency, EPA's 
Office of Solid Waste and Emergency Response (OSWER) formed an 
Environmental Justice Task Force to analyze the array of environmental 
justice issues specific to waste programs and to develop an overall 
strategy to identify and address these issues (OSWER Directive No. 
9200.3-17).
    We have no data indicating that today's proposal would result in 
disproportionately negative impacts on minority or low income 
communities. The public is invited to comment and submit data related 
to environmental justice issues potentially associated with today's 
proposal.

V. Unfunded Mandates Reform Act

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public 
Law 104-4, establishes requirements for Federal agencies to assess the 
effects of their regulatory actions on State, local, and tribal 
governments and the private sector. Under section 202 of the UMRA, EPA 
generally must prepare a written statement, including a cost-benefit 
analysis, for proposed and final rules with ``Federal mandates'' that 
may result in expenditures to State, local, and tribal governments, in 
the aggregate, or to the private sector, of $100 million or more in any 
single year. Before promulgating an EPA rule for which a written 
statement is needed, section 205 of the UMRA generally requires EPA to 
identify and consider a reasonable number of regulatory alternatives 
and adopt the least costly, most cost-effective or least burdensome 
alternative that achieves the objectives of the rule. The provisions of 
section 205 do not apply when they are inconsistent with applicable 
law. Moreover, section 205 allows EPA to adopt an alternative other 
than the least costly, most cost-effective or least burdensome 
alternative if the Administrator publishes with the final rule an 
explanation why that alternative was not adopted. Before EPA 
establishes any regulatory requirements that may significantly or 
uniquely affect small governments, including tribal governments, it 
must have developed under section 203 of the UMRA a small government 
agency plan. The plan must provide for notifying potentially affected 
small governments, enabling officials of affected small governments to 
have meaningful and timely input in the development of EPA regulatory 
proposals with significant Federal intergovernmental mandates, and 
informing, educating, and advising small governments on compliance with 
the regulatory requirements.
    We have determined that this rule does not contain a Federal 
mandate that may result in expenditures of $100 million or more for 
State, local, and tribal governments, in the aggregate, or the private 
sector in any single year. The amendments, as proposed, may result in 
increased costs to all states (or the Agency) of no more than 
approximately $160,000 per year. Thus, today's rule is not subject to 
the requirements of sections 202 and 205 of the UMRA.

VI. Executive Order 13132 (Federalism)

    Executive Order 13132, entitled ``Federalism'' (64 FR 43255, August 
10, 1999), requires EPA to develop an accountable process to ensure 
``meaningful and timely input by State and local officials in the 
development of regulatory policies that have federalism implications.'' 
``Policies that have federalism implications'' are defined in the 
Executive Order to include regulations that have ``substantial direct 
effects on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government.''
    This proposed rule does not have federalism implications. It will 
not have substantial direct effects on the States, on the relationship 
between the national government and the States, or on the distribution 
of power and responsibilities among the various levels of government, 
as specified in Executive Order 13132. This rule, as proposed, is 
projected to result in economic impacts to privately owned hazardous 
waste combustion facilities. Marginal administrative burden impacts may 
occur to selected States an/or EPA Regional Offices if these entities 
experience increased administrative needs, enforcement requirements, or 
information requests. However, this rule, as proposed, will not have 
substantial direct effects on the States, intergovernmental 
relationships, or the distribution of power and responsibilities. Thus, 
Executive Order 13132 does not apply to this rule.
    In the spirit of Executive Order 13132, and consistent with EPA 
policy to promote communications between EPA and State and local 
governments, we specifically solicit comment on this proposed rule from 
State and local officials.

VII. Consultation With Tribal Governments

    Executive Order 13175, entitled ``Consultation and Coordination 
with Indian Tribal Governments'' (65 FR 67249, November 6, 2000), 
requires EPA to develop an accountable process to ensure ``meaningful 
and timely input by tribal officials in the development of regulatory 
policies that have tribal implications.'' ``Policies that have tribal 
implications'' is defined in the Executive Order to include regulations 
that have ``substantial direct effects on one or more Indian tribes, on 
the relationship between the Federal government and the Indian tribes, 
or on the distribution of power and responsibilities between the 
Federal government and Indian tribes.''
    This proposed rule does not have tribal implications. It will not 
have substantial direct effects on tribal governments, on the 
relationship between the Federal government and Indian tribes, or on 
the distribution of power and responsibilities between the Federal 
government and Indian tribes, as specified in Executive Order 13175. 
Today's proposal would not significantly or uniquely affect the 
communities of Indian tribal governments, nor would it impose 
substantial direct compliance costs on them. Tribal communities are not 
known to own or operate any hazardous waste combustion facilities, nor 
are these communities disproportionately located adjacent to or near 
such facilities. Finally, tribal governments will not be required to 
assume any administrative or permitting responsibilities associated 
with this proposed rule.
    In the spirit of Executive Order 13175, and consistent with EPA 
policy to promote communications between EPA and tribal governments, we 
specifically request comment on this proposed rule from tribal 
officials.

[[Page 35151]]

VIII. Paperwork Reduction Act

    We have prepared an Information Collection Request (ICR) document 
(ICR No. 1773.03) listing the information collection requirements of 
this proposed rule, and have submitted it for approval to the Office of 
Management and Budget (OMB) under the provisions of the Paperwork 
Reduction Act, 44 U.S.C. 3501 et seq. OMB has assigned a control number 
2050-0171 for this ICR. A copy of this ICR may be obtained from Sandy 
Farmer, OPIA Regulatory Information Division, U.S. Environment 
Protection Agency (2137), 1200 Pennsylvania Avenue NW, Washington, DC 
20460, or by calling (202) 260-2740.
    Some of the amendments proposed today pertain to RCRA provisions of 
the rule (i.e. to 40 CFR parts 260 thru 271), and were covered under an 
earlier ICR No. 1361.08. Today's amendments to these RCRA provisions 
are all de-regulatory, and do not impose any burden on the regulated 
community. They only reduce the existing burden shown in that ICR. The 
ICR No. 1361.08 will be revised to show the reduced burden when the 
final rule is promulgated. The public burden associated with other 
provisions of this proposed rule (which are under the Clean Air Act) is 
projected to affect approximately 171 HWC units and is estimated to 
average 8.7 hours per respondent annually. The reporting and 
recordkeeping cost burden is estimated to average $511 per respondent 
annually. Burden means total time, effort, or financial resources 
expended by persons to generate, maintain, retain, disclose, or provide 
information to or for a Federal agency. That 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; 
search data sources; complete and review the collection of information; 
and transmit or otherwise disclose the information.
    Comments are requested on the need of this information, accuracy of 
the provided burden estimates, and any suggested methods for minimizing 
the respondent burden. Send comments to Sandy Farmer at the address 
given above, 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.'' The final rule will respond 
to all OMB and public comments on the information collection 
requirements contained in this proposal.
    We note that the recordkeeping and reporting requirements are 
specifically authorized by section 114 of the CAA (42 U.S.C. 7414). All 
information submitted to the EPA for which a claim of confidentiality 
is made will be safeguarded according to EPA policies in 40 CFR part 2, 
subpart B, Confidentiality of Business 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 chapter 15. The EPA 
will amend the table in 40 CFR part 9 of currently approved information 
collection request (ICR) control numbers issued by OMB upon 
finalization of this rule and list the information collection 
requirements contained in the final rule.

IX. National Technology Transfer and Advancement Act of 1995

    Section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (``NTTAA''), Public Law 104-113, section 12(d) (15 U.S.C. 
272 note) directs EPA to use voluntary consensus standards in its 
regulatory activities unless to do so would be inconsistent with 
applicable law or otherwise impractical. Voluntary consensus standards 
are technical standards (e.g., materials specifications, test methods, 
sampling procedures, and business practices) that are developed or 
adopted by voluntary consensus standards bodies. The NTTAA directs EPA 
to provide Congress, through OMB, explanations when the Agency decides 
not to use available and applicable voluntary consensus standards.
    This proposed rulemaking does not involve technical standards. 
Therefore, we are not considering the use of any voluntary consensus 
standards. We welcome comments on this aspect of the proposed 
rulemaking and, specifically, invite the public to identify potentially 
applicable voluntary consensus standards and to explain why such 
standards should be used in this regulation.

Part Four: State Authority

    States can implement and enforce the new MACT standards through 
their delegated 112(l) CAA program and/or by having title V authority. 
A State's title V authority is independent of whether it has been 
delegated section 112(l) of the CAA. Additional information on state 
authority under the CAA may be found in the HWC MACT rule (64 FR at 
52991).

List of Subjects

40 CFR Part 63

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

40 CFR Part 264

    Environmental protection, Air pollution control, Hazardous waste, 
Insurance, Packaging and containers, Reporting and recordkeeping 
requirements, Security measures, Surety bonds

40 CFR Part 265

    Environmental protection, Air pollution control, Hazardous waste, 
Insurance, Packaging and containers, Reporting and recordkeeping 
requirements, Security measures, Surety bonds, Water supply.

40 CFR Part 266

    Environmental protection, Energy, Hazardous waste, Recycling, 
Reporting and recordkeeping requirements

40 CFR Part 270

    Environmental protection, Administrative practice and procedure, 
Confidential business information, Hazardous materials transportation, 
Hazardous waste, Reporting and recordkeeping requirements, Water 
pollution control, Water supply.

    Dated: June 18, 2001.
Christine Todd Whitman,
Administrator.
    For the reasons set out in the preamble, it is proposed that title 
40 of the Code of Federal Regulations is amended as follows:

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

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

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

    2. Section 63.14 is amended by adding paragraph (i) to read as 
follows:


Sec. 63.14  Incorporations by reference.

* * * * *
    (i) ASME standard. This standard is available from the American 
Society of Mechanical Engineers, 345 East 47th Street, New York, N.Y. 
10017: Standard for the Qualification and Certification of Hazardous 
Waste Incinerator Operators, ASME QHO-1-1994.

[[Page 35152]]

    3. Section 63.1201 is amended by revising the definition of 
``Instantaneous monitoring'' in paragraph (a) to read as follows:


Sec. 63.1201  Definitions and acronyms used in this subpart.

    (a) * * *
    Instantaneous monitoring for combustion system leak control means 
detecting and recording pressure, without use of an averaging period, 
at a frequency adequate to detect combustion system leak events from 
hazardous waste combustion.
* * * * *
    4. Section 63.1206 is amended by revising paragraph (c)(5)(ii) and 
(c)(6) to read as follows:


Sec. 63.1206  When and how must you comply with the standards and 
operating requirements?

* * * * *
    (c) * * *
    (5) * * *
    (ii) You must specify in the performance test workplan and 
Notification of Compliance the method that will be used to control 
combustion system leaks. If you control combustion system leaks by 
maintaining the combustion zone pressure lower than ambient pressure 
using an instantaneous monitor, you must also specify in the 
performance test workplan and Notification of Compliance the monitoring 
and recording frequency of the pressure monitor, and specify how the 
monitoring approach will be integrated into the automatic waste feed 
cutoff system.
    (6) Operator training and certification. (i) You must establish 
training programs for all categories of personnel whose activities may 
reasonably be expected to directly affect emissions of hazardous air 
pollutants from the source. Such persons include, but are not limited 
to, chief facility operators, control room operators, continuous 
monitoring system operators, persons that sample and analyze 
feedstreams, persons that manage and charge feedstreams to the 
combustor, persons that operate emission control devices, and ash and 
waste handlers. Each training program shall be of a technical level 
commensurate with the person's job duties specified in the training 
manual. Each commensurate training program shall require an examination 
to be administered by the instructor at the end of the training course. 
Passing of this test shall be deemed the ``certification'' for 
personnel, except that, for control room operators, the training and 
certification program shall be as specified in paragraphs (c)(6)(iii) 
through (c)(6)(vi) of this section.
    (ii) You must ensure that the source is operated and maintained at 
all times by persons who are trained and certified to perform these and 
any other duties that may affect emissions of hazardous air pollutants. 
A certified control room operator must be on duty at the site at all 
times the source is in operation.
    (iii) Hazardous waste incinerator control room operators must:
    (A) Be trained and certified under a site-specific, source-
developed and implemented program that meets the requirements of 
paragraph (c)(6)(v) of this section; or
    (B) Be trained under the requirements of, and certified under, the 
American Society of Mechanical Engineers Standard Number QHO-1-1994 
(incorporated by reference--see Sec. 63.14(e)). If you choose to use 
the ASME program:
    (1) Control room operators must, prior to the compliance date, 
achieve provisional certification, and must submit an application to 
ASME and be scheduled for the full certification exam. Within one year 
of the compliance date, control room operators must achieve full 
certification;
    (2) New operators and operators of new sources must, before 
assuming their duties, achieve provisional certification, and must 
submit an application to ASME, and be scheduled for the full 
certification exam. Within one year of assuming their duties, these 
operators must achieve full certification; or
    (C) Be trained and certified under a State program.
    (iv) Cement kiln and lightweight aggregate kiln control room 
operators must be trained and certified under:
    (A) A site-specific, source-developed and implemented program that 
meets the requirements of paragraph (c)(6)(v) of this section; or
    (B) A State program.
    (v) Site-specific, source developed and implemented training 
programs for control room operators must include the following 
elements:
    (A) Training on the following subjects:
    (1) Environmental concerns, including types of emissions;
    (2) Basic combustion principles, including products of combustion;
    (3) Operation of the specific type of combustor used by the 
operator, including proper startup, waste firing, and shutdown 
procedures;
    (4) Combustion controls and continuous monitoring systems;
    (5) Operation of air pollution control equipment and factors 
affecting performance;
    (6) Inspection and maintenance of the combustor, continuous 
monitoring systems, and air pollution control devices;
    (7) Actions to correct malfunctions or conditions that may lead to 
malfunction;
    (8) Residue characteristics and handling procedures; and
    (9) Applicable Federal, state, and local regulations, including 
Occupational Safety and Health Administration workplace standards; and
    (B) An examination designed and administered by the instructor; and
    (C) Written material covering the training course topics that may 
serve as reference material following completion of the course.
    (vi) To maintain control room operator qualification under a site-
specific, source developed and implemented training program as provided 
by paragraph (c)(6)(v) of this section, control room operators must 
complete an annual review or refresher course covering, at a minimum, 
the following topics:
    (A) Update of regulations;
    (B) Combustor operation, including startup and shutdown procedures, 
waste firing, and residue handling;
    (C) Inspection and maintenance;
    (D) Responses to malfunctions or conditions that may lead to 
malfunction; and
    (E) Operating problems encountered by the operator.
    (vii) You must record the operator training and certification 
program in the operating record.
* * * * *
    5. Section 63.1207 is amended by:
    a. Revising paragraphs (g)(2)(i) and (g)(2)(ii).
    b. Revising paragraph (h)(2) introductory text.
    c. Revising paragraph (j)(1)(i).
    d. Adding paragraph (e)(3).
    e. Adding paragraph (g)(2)(iv).
    f. Adding paragraph (j)(5).
    The revisions and additions read as follows:


Sec. 63.1207  What are the performance testing requirements?

* * * * *
    (e) * * *
    (3) Petitions for time extension if Administrator fails to approve 
or deny test plans. You may petition the Administrator under 
Sec. 63.7(h) to obtain a ``waiver'' of any performance test-- initial 
or periodic performance test; comprehensive or confirmatory test. The 
``waiver'' would be implemented as an extension of time to conduct the 
performance test at a later date.

[[Page 35153]]

    (i) Qualifications for the waiver. (A) You may not petition the 
Administrator for a waiver under this section if the Administrator has 
issued a notification of intent to deny your test plan(s) under 
Sec. 63.7(c)(3)(i)(B).
    (B) You must submit a site-specific emissions testing plan and a 
continuous monitoring system performance evaluation plan at least one 
year before a comprehensive performance test is scheduled to begin as 
required by paragraph (c)(1) of this section, or at least 60 days 
before a confirmatory performance test is scheduled to begin as 
required by paragraph (d) of this section. The test plans must include 
all documentation required to be included, including the substantive 
content requirements of paragraph (f) of this section and Sec. 63.8(e); 
and
    (C) You must make a good faith effort to accommodate the 
Administrator's comments on the test plans.
    (ii) Procedures for obtaining a waiver and duration of the waiver: 
(A) You must submit to the Administrator a waiver petition or request 
to renew the petition under Sec. 63.7(h) separately for each source at 
least 60 days prior to the scheduled date of the performance test.
    (B) The Administrator will approve or deny the petition within 30 
days of receipt and notify you promptly of the decision.
    (C) The Administrator will not approve an individual waiver 
petition for a duration exceeding 6 months;
    (D) The Administrator will include a sunset provision in the waiver 
ending the waiver within 6 months;
    (E) You may submit a revised petition to renew the waiver under 
Sec. 63.7(h)(3)(iii) at least 60 days prior to the end date of the most 
recently approved waiver petition;
    (F) The Administrator may approve a revised petition for a total 
waiver period up to 12 months.
    (iii) Content of the waiver. (A) You must provide documentation to 
enable the Administrator to determine that the source is meeting the 
relevant standard(s) on a continuous basis as required by 
Sec. 63.7(h)(2). For extension requests for the initial comprehensive 
performance test, you must submit your Documentation of Compliance to 
assist the Administrator in making this determination.
    (B) You must include in the petition information justifying your 
request for a waiver, such as the technical or economic infeasibility, 
or the impracticality, of the affected source performing the required 
test, as required by Sec. 63.7(h)(3)(iii).
    (iv) Public notice. You must notify the public (e.g., distribute 
public mailing list) of your petition to waive a performance test.
* * * * *
    (g) * * *
    (2) * * *
    (i) Carbon monoxide (or hydrocarbon) CEMS emissions levels must be 
within the range of the average value to the maximum value allowed, 
except as provided by paragraph (g)(2)(iv) of this section. The average 
value is defined as the sum of the hourly rolling average values 
recorded (each minute) over the previous 12 months divided by the 
number of rolling averages recorded during that time;
    (ii) Each operating limit (specified in Sec. 63.1209) established 
to maintain compliance with the dioxin/furan emission standard must be 
held within the range of the average value over the previous 12 months 
and the maximum or minimum, as appropriate, that is allowed, except as 
provided by paragraph (g)(2)(iv) of this section. The average value is 
defined as the sum of the rolling average values recorded over the 
previous 12 months divided by the number of rolling averages recorded 
during that time. The average value must not include calibration data, 
malfunction data, and data obtained when not burning hazardous waste;
* * * * *
    (iv) The Administrator may approve an alternative range to that 
required by paragraphs (g)(2)(i) and (ii) of this section if you 
document in the confirmatory performance test plan that it may be 
problematic to maintain the required range during the test. In 
addition, when making the finding of compliance, the Administrator may 
consider test conditions outside of the range specified in the test 
plan based on a finding that you could not reasonably maintain the 
range specified in the test plan and considering factors including 
whether the time duration and level of the parameter when operations 
were out of the specified range were such that operations during the 
confirmatory test are determined to be reasonably representative of 
normal operations. In addition, the Administrator will consider the 
proximity of the emission test results to the standard.
* * * * *
    (h) * * *
    (2) Current operating parameters limits are also waived during 
pretesting prior to comprehensive performance testing for an aggregate 
time not to exceed 720 hours of operation under an approved test plan 
or if the source records the results of the pretesting. Pretesting 
means:
* * * * *
    (j) * * *
    (1) * * *
    (i) Except as provided by paragraphs (j)(4) and (j)(5) of this 
section, within 90 days of completion of a comprehensive performance 
test, you must postmark a Notification of Compliance documenting 
compliance or noncompliance with the emission standards and continuous 
monitoring system requirements, and identifying operating parameter 
limits under Sec. 63.1209.
* * * * *
    (5) Early compliance. If you conduct the initial comprehensive 
performance test prior to September 30, 2002 (or a later compliance 
date approved under Sec. 63.6(i)), you need not postmark the 
Notification of Compliance within 90 days of completion of the 
performance test.
* * * * *
    6. Section 63.1209 is amended by:
    a. Revising paragraphs (k)(5) and (k)(7)(i)(C).
    b. Revising paragraphs (l)(3) and (l)(4).
    c. Revising paragraph (p).
    d. Revising paragraph (q).
    e. Adding paragraph (k)(6)(iv).
    These revisions and additions read as follows:


Sec. 63.1209  What are the monitoring requirements?

* * * * *
    (k) * * *
    (5) Particulate matter operating limit. If your combustor is 
equipped with an activated carbon injection system, you must establish 
operating parameter limits on the particulate matter control device as 
specified by paragraph (m)(1) of this section;
    (6) * * *
    (iv) Control device operating parameter limits (OPLs). You must 
establish operating parameter limits on the particulate matter control 
device as specified by paragraph (m)(1) of this section.
    (7) * * *
    (i) * * *
    (C) For the initial comprehensive performance test, you may base 
the initial limit on maximum bed age of the carbon in each segment of 
the bed on manufacturer's specifications. If you use manufacturer's 
specifications rather than actual bed age to establish the initial 
limit, you must also conduct a bed life confirmatory test prior to the 
manufacturer's specification of bed age. That bed life confirmatory 
test must be conducted under the procedures required for a dioxin/furan 
confirmatory test as specified by Sec. 63.1207(g)(2). The purpose of 
the bed life confirmatory test is to document to the Administrator that

[[Page 35154]]

the initial limit on maximum bed age ensures compliance with the 
dioxin/furan emission standard. If you fail to confirm compliance with 
the dioxin/furan emission standard during this testing, you must 
conduct additional testing as necessary to document that a revised 
lower limit on maximum bed age ensures compliance with the dioxin/furan 
standard.
* * * * *
    (l) * * *
    (3) Activated carbon injection. If your combustor is equipped with 
an activated carbon injection system, you must establish operating 
parameter limits prescribed by paragraphs (k)(5) and (k)(6) of this 
section.
    (4) Activated carbon bed. If your combustor is equipped with a 
carbon bed system, you must establish operating parameter limits 
prescribed by paragraph (k)(7) of this section. In addition, if you 
elect to establish the initial limit on carbon bed age based on the 
manufacturer's specification, you must:
    (i) Operate the combustor during the bed life confirmatory test 
required by paragraph (k)(7)(i)(C) of this section such that each 
operating limit specified in paragraph (l) of this section is held 
within the range of the average value over the previous 12 months and 
the maximum or minimum, as appropriate, that is allowed. The term 
``average value'' is defined in Sec. 63.1207(g)(2)(ii); and
    (ii) Conduct mercury emissions testing to document compliance with 
the mercury emission standard. If you fail to confirm compliance with 
the mercury emission standard during this testing, you must conduct 
additional testing as necessary to document that a revised lower limit 
on maximum bed age ensures compliance with the standard.
* * * * *
    (p) Maximum combustion chamber pressure. If you comply with the 
requirements for combustion system leaks under Sec. 63.1206(c)(5) by 
maintaining the maximum combustion chamber zone pressure lower than 
ambient pressure to prevent combustion system leaks from hazardous 
waste combustion, you must perform instantaneous monitoring of pressure 
and the automatic waste feed cutoff system must be engaged when 
negative pressure is not adequately maintained.
    (q) Operating under different modes of operation. If you operate 
under different modes of operation, you must establish operating 
parameter limits for each mode. You must document in the operating 
record when you change a mode of operation and begin complying with the 
operating limits for an alternative mode of operation.
    (1) Operating under otherwise applicable standards after the 
hazardous waste residence time has transpired. As provided by 
Sec. 63.1206(b)(1)(ii), you may operate under otherwise applicable 
requirements promulgated under sections 112 and 129 of the Clean Air 
Act in lieu of the substantive requirements of this subpart.
    (i) The otherwise applicable requirements promulgated under 
sections 112 and 129 of the Clean Air Act are applicable requirements 
under this subpart.
    (ii) You must specify (e.g., by reference) the otherwise applicable 
requirements as a mode of operation in your Documentation of Compliance 
under Sec. 63.1211(d), your Notification of Compliance under 
Sec. 63.1207(j), and your title V permit application. These 
requirements include the otherwise applicable requirements governing 
emission standards, monitoring and compliance, and notification, 
reporting, and recordkeeping.
    (2) Calculating rolling averages under different modes of 
operation. When you transition to a different mode of operation, you 
must calculate rolling averages anew using the continuous monitoring 
system values previously recorded for that mode of operation (i.e., you 
ignore continuous monitoring system values recorded under other modes 
of operations when you transition back to a mode of operation).

PART 264--STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE 
TREATMENT, STORAGE, AND DISPOSAL FACILITIES

    7. The authority citation for part 264 continues to read as 
follows:

    Authority: 42 U.S.C. 6905, 6912(a), 6924, and 6925.

    8. Section 264.340 is amended by redesignating paragraph (b)(2) as 
paragraph (b)(3); revising the first sentence in paragraph (b)(1); and 
adding new paragraph (b)(2) to read as follows:


Sec. 264.340  Applicability.

* * * * *
    (b) * * *
    (1) Except as provided by paragraph (b)(3) of this section, the 
standards of this part no longer apply when an owner or operator 
demonstrates compliance with the maximum achievable control technology 
(MACT) requirements of part 63, subpart EEE of this chapter by 
conducting a comprehensive performance test and submitting to the 
Administrator a Notification of Compliance under Secs. 63.1207(j) and 
63.1210(d) of this chapter documenting compliance with the requirements 
of part 63, subpart EEE of this chapter. * * *
    (2) Except as provided by paragraph (b)(3) of this section, the 
standards of this section do not apply to an owner or operator of a 
hazardous waste incinerator (as defined at Sec. 63.1201 of this 
chapter) that begins construction, reconstruction, or becomes an 
affected source of part 63, subpart EEE of this chapter, after 
September 30, 1999.
* * * * *

PART 265--INTERIM STATUS STANDARDS FOR OWNERS AND OPERATORS OF 
HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES

    9. The authority citation for part 265 continues to read as 
follows:

    Authority: 42 U.S.C. 6905, 6906, 6912, 6922, 6923, 6924, 6925, 
6935, 6936, and 6937.

    10. Section 265.340 is amended by redesignating paragraph (b)(2) as 
paragraph (b)(3); revising the first sentence in paragraph (b)(1); and 
adding a new paragraph (b)(2) to read as follows:


Sec. 265.340  Applicability.

* * * * *
    (b) * * *
    (1) Except as provided by paragraph (b)(3) of this section, the 
standards of this part no longer apply when an owner or operator 
demonstrates compliance with the maximum achievable control technology 
(MACT) requirements of part 63, subpart EEE of this chapter by 
conducting a comprehensive performance test and submitting to the 
Administrator a Notification of Compliance under Secs. 63.1207(j) and 
63.1210(d) of this chapter documenting compliance with the requirements 
of part 63, subpart EEE of this chapter. * * *
    (2) Except as provided by paragraph (b)(3) of this section, the 
standards of this section do not apply to an owner or operator begins 
construction, reconstruction, or becomes an affected source of part 63, 
subpart EEE of this chapter, after September 30, 1999.
* * * * *

[[Page 35155]]

PART 266--STANDARDS FOR THE MANAGEMENT OF SPECIFIC HAZARDOUS WASTES 
AND SPECIFIC TYPES OF HAZARDOUS WASTE MANAGEMENT FACILITIES

    11. The authority citation for part 266 continues to read as 
follows:

    Authority: Secs. 1006, 2002(a), 3004, 6905, 6906, 6912, 6922, 
6925, and 6937.

    12. Section 266.100 is amended by redesignating paragraph (b)(2) as 
paragraph (b)(3); revising the first sentence of paragraph (b)(1); and 
adding new paragraph (b)(2) to read as follows:


Sec. 266.100  Applicability.

* * * * *
    (b) * * *
    (1) Except as provided by paragraph (b)(3) of this section, the 
standards of this part no longer apply when an affected source 
demonstrates compliance with the maximum achievable control technology 
(MACT) requirements of part 63, subpart EEE, of this chapter by 
conducting a comprehensive performance test and submitting to the 
Administrator a Notification of Compliance under Secs. 63.1207(j) and 
63.1210(d) of this chapter documenting compliance with the requirements 
of subpart EEE. * * *
    (2) Except as provided by paragraph (b)(3) of this section, the 
standards of this section do not apply to an owner or operator of a 
hazardous waste burning cement kiln, or hazardous waste lightweight 
aggregate kiln (as defined at Sec. 63.1201 of this chapter) that begins 
construction, reconstruction, or becomes an affected source of part 63, 
subpart EEE of this chapter, after September 30, 1999.
* * * * *

PART 270--EPA ADMINISTERED PERMIT PROGRAMS: THE HAZARDOUS WASTE 
PERMIT PROGRAM

    13. The authority citation for part 270 continues to read as 
follows:

    Authority: 42 U.S.C. 6905, 6912, 6924, 6925, 6927, 6939, and 
6974.

    14. Section 270.19 is amended by revising paragraph (e) to read as 
follows:


Sec. 270.19  Specific part B information requirements for incinerators.

* * * * *
    (e) When an owner or operator who submitted a permit application 
under this part before September 30, 1999, demonstrates compliance with 
the air emission standards and limitations in 40 CFR part 63, subpart 
EEE (i.e., by conducting a comprehensive performance test and 
submitting a Notification of Compliance documenting compliance with all 
applicable requirements of part 63, subpart EEE), the requirements of 
this section do not apply. When an owner or operator submits a permit 
application under this part on or after September 30, 1999, the 
requirements of this section do not apply. Nevertheless, the Director 
may apply the provisions of this section, on a case-by-case basis, for 
purposes of information collection in accordance with Secs. 270.10(k) 
and 270.32(b)(2).
    15. Section 270.22 is amended by revising the introductory text to 
read as follows:


Sec. 270.22  Specific part B information requirements for boilers and 
industrial furnaces burning hazardous waste.

    When an owner or operator of a cement or lightweight aggregate kiln 
demonstrates compliance with the air emission standards and limitations 
in 40 CFR part 63, subpart EEE (i.e., by conducting a comprehensive 
performance test and submitting a Notification of Compliance 
documenting compliance with all applicable requirements of part 63, 
subpart EEE), the requirements of this section do not apply. When an 
owner or operator of a cement or lightweight aggregate kiln submits a 
permit application under this part on or after September 30, 1999, the 
requirements of this section do not apply. Nevertheless, the Director 
may apply the provisions of this section, on a case-by-case basis, for 
purposes of information collection in accordance with Secs. 270.10(k) 
and 270.32(b)(2).
* * * * *
    16. Section 270.62 is amended by revising the introductory text to 
read as follows:


Sec. 270.62  Hazardous waste incinerator permits.

    When an owner or operator who submitted a permit application under 
this part before September 30, 1999, demonstrates compliance with the 
air emission standards and limitations in 40 CFR part 63, subpart EEE 
(i.e., by conducting a comprehensive performance test and submitting a 
Notification of Compliance documenting compliance with all applicable 
requirements of 40 CFR part 63, subpart EEE), the requirements of this 
section do not apply. When an owner or operator submits a permit 
application under this part on or after September 30, 1999, the 
requirements of this section do not apply. Nevertheless, the Director 
may apply the provisions of this section, on a case-by-case basis, for 
purposes of information collection in accordance with Secs. 270.10(k) 
and 270.32(b)(2).
* * * * *
    17. Section 270.66 is amended by revising the introductory text to 
read as follows:


Sec. 270.66  Permits for boilers and industrial furnaces burning 
hazardous waste.

    When an owner or operator of a cement or lightweight aggregate kiln 
who submitted a permit application under this part before September 30, 
1999, demonstrates compliance with the air emission standards and 
limitations in 40 CFR part 63, subpart EEE (i.e., by conducting a 
comprehensive performance test and submitting a Notification of 
Compliance documenting compliance with all applicable requirements of 
40 CFR part 63, subpart EEE), the requirements of this section do not 
apply. When an owner or operator of a cement or lightweight aggregate 
kiln submits a permit application under this part on or after September 
30, 1999, the requirements of this section do not apply. Nevertheless, 
the Director may apply the provisions of this section, on a case-by-
case basis, for purposes of information collection in accordance with 
Secs. 270.10(k) and 270.32(b)(2).
* * * * *
[FR Doc. 01-16426 Filed 7-2-01; 8:45 am]
BILLING CODE 6560-50-U