[Federal Register Volume 71, Number 172 (Wednesday, September 6, 2006)]
[Proposed Rules]
[Pages 52624-52653]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 06-7251]



[[Page 52623]]

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Part II





Environmental Protection Agency





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40 CFR Parts 63, 264, and 266



NESHAP: National Emission Standards for Hazardous Air Pollutants: 
Standards for Hazardous Waste Combustors (Reconsideration); Proposed 
Rule

  Federal Register / Vol. 71, No. 172 / Wednesday, September 6, 2006 / 
Proposed Rules  

[[Page 52624]]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 63, 264 and 266

[EPA-HQ-OAR-2004-0022; FRL-8215-3]
RIN 2050-AG29


NESHAP: National Emission Standards for Hazardous Air Pollutants: 
Standards for Hazardous Waste Combustors (Reconsideration)

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: On October 12, 2005, EPA promulgated national emission 
standards for hazardous air pollutants (NESHAP) for new and existing 
hazardous waste combustors. Subsequently, the Administrator received 
four petitions for reconsideration of the final rule. In this proposed 
rule, EPA is granting reconsideration of and requesting comment on 
several issues raised in the petitions of the Cement Kiln Recycling 
Coalition, the Coalition for Responsible Waste Incineration, and the 
Sierra Club. In addition, EPA is proposing several amendments and 
corrections to the final rule to clarify some compliance and monitoring 
issues raised by several entities affected by the final rule.

DATES: Comments. Written comments must be received by October 23, 2006.
    Public Hearing. A public hearing will be held on September 21, 
2006. For further information on the public hearing and requests to 
speak, see the ADDRESSES section of this preamble.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2004-0022, by one of the following methods:
     Federal eRulemaking Portal: http://www.regulations.gov. 
Follow the on-line instructions for submitting comments.
     E-mail: [email protected].
     Fax: 202-566-1741.
     Mail: U.S. Postal Service, send comments to: HQ EPA Docket 
Center (6102T), Attention Docket ID No. EPA-HQ-OAR-2004-0022, 1200 
Pennsylvania Avenue, NW., Washington, DC 20460. Please include a total 
of two copies. We request that you also send a separate copy of each 
comment to the contact person listed below (see FOR FURTHER INFORMATION 
CONTACT).
     Hand Delivery: In person or by courier, deliver comments 
to: HQ EPA Docket Center (6102T), Attention Docket ID No. EPA-HQ-OAR-
2004-0022, 1301 Constitution Avenue, NW., Room B-108, Washington, DC 
20004. Such deliveries are only accepted during the Docket's normal 
hours of operation, and special arrangements should be made for 
deliveries of boxed information. Please include a total of two copies. 
We request that you also send a separate copy of each comment to the 
contact person listed below (see FOR FURTHER INFORMATION CONTACT).
    Instructions: Direct your comments to Docket ID No. EPA-HQ-OAR-
2004-0022. The EPA's policy is that all comments received will be 
included in the public docket without change and may be made available 
online at www.regulations.gov, including any personal information 
provided, unless the comments include information claimed to be 
Confidential Business Information (CBI) or other information the 
disclosure of which is restricted by statute. Do not submit information 
that you consider to be CBI or otherwise protected through 
www.regulations.gov or e-mail. Send or deliver information identified 
as CBI to only the following address: Ms. LaShan Haynes, RCRA Document 
Control Officer, EPA (Mail Code 5305W), Attention Docket ID No. EPA-HQ-
OAR-2004-0022, 1200 Pennsylvania Avenue, Washington DC, 20460. Clearly 
mark the part or all of the information that you claim to be CBI. The 
www.regulations.gov Web site is an ``anonymous access'' system, which 
means EPA will not know your identity or contact information unless you 
provide it in the body of your comment. If you send an e-mail comment 
directly to EPA without going through www.regulations.gov, your e-mail 
address will be automatically captured and included as part of the 
comment that is placed in the public docket and made available on the 
Internet. If you submit an electronic comment, EPA recommends that you 
include your name and other contact information in the body of your 
comment and with any disk or CD-ROM you submit. If EPA cannot read your 
comment due to technical difficulties and cannot contact you for 
clarification, EPA may not be able to consider your comment. Electronic 
files should avoid the use of special characters, any form of 
encryption, and be free of any defects or viruses. For additional 
information about EPA's public docket visit the EPA Docket Center 
homepage at http://www.epa.gov/epahome/dockets.htm. We also request 
that interested parties who would like information they previously 
submitted to EPA to be considered as part of this reconsideration 
action identify the relevant information by docket entry numbers and 
page numbers.
    Docket: All documents in the docket are listed in the 
www.regulations.gov index. Although listed in the index, some 
information is not publicly available, e.g., CBI or other information 
the disclosure of which is restricted by statute. Certain other 
material, such as copyrighted material, will be publicly available only 
in hard copy. Publicly available docket materials are available either 
electronically in www.regulations.gov or in hard copy at the HQ EPA 
Docket Center, Docket ID No. EPA-HQ-OAR-2004-0022, EPA West Building, 
Room B-102, 1301 Constitution Ave., NW., Washington, DC 20004. This 
Docket Facility is open from 8:30 a.m. to 4:30 p.m., Monday through 
Friday, excluding legal holidays. The HQ EPA Docket Center telephone 
number is (202) 566-1742. The Public Reading Room is open from 8:30 
a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The 
telephone number for the Public Reading Room is (202) 566-1744. A 
reasonable fee may be charged for copying docket materials.


    Note: The EPA Docket Center suffered damage due to flooding 
during the last week of June 2006. The Docket Center is continuing 
to operate. However, during the cleanup, there will be temporary 
changes to Docket Center telephone numbers, addresses, and hours of 
operation for people who wish to make hand deliveries or visit the 
Public Reading Room to view documents. Consult EPA's Federal 
Register notice at 71 FR 38147 (July 5, 2006) or the EPA Web site at 
http://www.epa.gov/epahome/dockets.htm for current information on 
docket operations, locations and telephone numbers. The Docket 
Center's mailing address for U.S. mail and the procedure for 
submitting comments to www.regulations.gov are not affected by the 
flooding and will remain the same.


    Public Hearing. The public hearing will run from 9 a.m. to 5 p.m., 
Eastern standard time, and will be held at the Two Potomac Yard 
building, 2733 S. Crystal Drive, Arlington, Virginia, 22202. Persons 
interested in attending the hearing or wishing to present oral 
testimony should notify Mr. Frank Behan at least 2 days in advance of 
the public hearing (see FOR FURTHER INFORMATION CONTACT section of this 
preamble). The public hearing will provide interested parties the 
opportunity to present data, views, or arguments concerning this 
notice. If no one contacts Mr. Behan in advance of the hearing with a 
request to present oral testimony at the hearing, we will cancel the 
hearing. The record for this action will remain open for 30 days after 
the date of the hearing to accommodate submittal of information related 
to the public hearing.

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FOR FURTHER INFORMATION CONTACT: For more information on this 
rulemaking, contact Frank Behan at (703) 308-8476, or 
[email protected], Office of Solid Waste (MC: 5302W), U.S. 
Environmental Protection Agency, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460.

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

I. General Information
    A. Does This Proposed Rule Apply to Me?
    B. How Do I Obtain a Copy of This Document and Other Related 
Information?
    C. What Should I Consider as I Prepare My Comments for EPA?
II. Background
III. Summary of This Action
IV. Discussion of Issues Subject to Reconsideration
    A. Subcategorization of Liquid Fuel Boilers by Heating Value
    B. Correcting Total Chlorine (TCl) Data to 20 ppmv
    C. Use of PS-11 and Procedure 2 as Guidance for Extrapolating 
the Alarm Set-Point of a Particulate Matter Detection System (PMDS)
    D. Tie-Breaking Procedure for New Source Standards
    E. Beyond-the-Floor Analyses to Consider Multiple HAP That Are 
Similarly Controlled
    F. Dioxin/Furan Standard for Incinerators With Dry Air Pollution 
Control Devices
    G. Provisions of the Health-Based Compliance Alternative
V. Other Proposed Amendments
    A. Sunset Provision for the Interim Standards
    B. Operating Parameter Limits for Sources With Fabric Filters
    C. Confirmatory Performance Testing Not Required for Sources 
That Are Not Subject to a Numerical Dioxin/Furan Emission Standard
    D. Periodic Performance Tests for Phase I Sources
    E. Performance Test Waiver for Sources Subject to Hazardous 
Waste Thermal Concentration Limits
    F. Averaging Method When Calculating 12-Hour Rolling Average 
Thermal Concentration Limits
    G. Calculating Rolling Averages for Averaging Periods in Excess 
of 12 Hours
    H. Calculating Rolling Averages
    I. Timing of the Periodic Review of Eligibility for the Health-
Based Compliance Alternatives for Total Chlorine
    J. Expressing Particulate Matter Standards Using the 
International System of Units (SI)
    K. Mercury Standards for Cement Kilns
    L. Facilities Operating Under RCRA Interim Status
VI. Revised Time Lines
VII. Technical Corrections and Other Clarification
    A. What Typographical Errors Would We Correct?
    B. What Citations Would We Correct?
    C. Corrections to the NIC Provisions for New Units
    D. Clarification of the Applicability of Title V Permit 
Requirements to Phase 2 Area Sources
VIII. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review
    B. Paperwork Reduction Act
    C. Regulatory Flexibility Act
    D. Unfunded Mandates Reform Act of 1995
    E. Executive Order 13132: Federalism
    F. Executive Order 13175: Consultation and Coordination With 
Indian Tribal Governments
    G. Executive Order 13045: Protection of Children From 
Environmental Health Risks and Safety Risks
    H. Executive Order 13211: Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use
    I. National Technology Transfer and Advancement Act

I. General Information

A. Does This Proposed Rule Apply to Me?

    Categories and entities potentially affected by this action 
include:

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                                                                                         Examples of potentially
               Category                           NAICS code                SIC code        regulated entities
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Any industry that combusts hazardous   562211..........................            4953  Incinerator, hazardous
 waste as defined in the final rule.                                                      waste.
                                       327310..........................            3241  Cement manufacturing,
                                                                                          clinker production.
                                       327992..........................            3295  Ground or treated
                                                                                          mineral and earth
                                                                                          manufacturing.
                                       325.............................              28  Chemical Manufacturers.
                                       324.............................              29  Petroleum Refiners.
                                       331.............................              33  Primary Aluminum.
                                       333.............................              38  Photographic equipment
                                                                                          and supplies.
                                       488, 561, 562...................              49  Sanitary Services,
                                                                                          N.E.C.
                                       421.............................              50  Scrap and waste
                                                                                          materials.
                                       422.............................              51  Chemical and Allied
                                                                                          Products, N.E.C.
                                       512, 541, 561, 812..............              73  Business Services,
                                                                                          N.E.C.
                                       512, 514, 541, 711..............              89  Services, N.E.C.
                                       924.............................              95  Air, Water and Solid
                                                                                          Waste Management.
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    This table is not intended to be exhaustive, but rather provides a 
guide for readers regarding entities likely to be impacted by this 
action. This table lists examples of the types of entities EPA is now 
aware could potentially be regulated by this action. Other types of 
entities not listed could also be affected. To determine whether your 
facility, company, business, organization, etc., is affected by this 
action, you should examine the applicability criteria in 40 CFR 
63.1200. If you have any questions regarding the applicability of this 
action to a particular entity, consult the person listed in the 
preceding FOR FURTHER INFORMATION CONTACT section.

B. How Do I Obtain a Copy of This Document and Other Related 
Information?

    In addition to being available in the docket, an electronic copy of 
today's proposed rule will also be available on the Worldwide Web 
(WWW). Following the Administrator's signature, a copy of this document 
will be posted on the WWW at http://www.epa.gov/hwcmact. This Web site 
also provides other information related to the NESHAP for hazardous 
waste combustors.

C. What Should I Consider as I Prepare My Comments for EPA?

    Submitting CBI. Do not submit this information to EPA through 
www.regulations.gov or e-mail. Clearly mark the part or all of the 
information that you claim to be CBI. For CBI information in a disk or 
CD ROM that you mail to EPA, mark the outside of the disk or CD ROM as 
CBI and then identify electronically within the disk or CD ROM the 
specific information that is claimed as CBI. In addition to one 
complete version of the comment that includes information claimed as 
CBI, a copy of the comment that does not

[[Page 52626]]

contain the information claimed as CBI must be submitted for inclusion 
in the public docket. Information so marked will not be disclosed 
except in accordance with procedures set forth in 40 CFR part 2.
    Tips for Preparing Your Comments. When submitting comments, 
remember to:
     Identify the rulemaking by docket number and other 
identifying information (subject heading, Federal Register date and 
page number).
     Follow directions--The agency may ask you to respond to 
specific questions or organize comments by referencing a Code of 
Federal Regulations (CFR) part or section number.
     Explain why you agree or disagree; suggest alternatives 
and substitute language for your requested changes.
     Describe any assumptions and provide any technical 
information and/or data that you used.
     If you estimate potential costs or burdens, explain how 
you arrived at your estimate in sufficient detail to allow it to be 
reproduced.
     Provide specific examples to illustrate your concerns, and 
suggest alternatives.
     Explain your views as clearly as possible.
     Make sure to submit your comments by the comment period 
deadline identified.

II. Background

    Section 112 of the CAA requires that we establish NESHAP for the 
control of hazardous air pollutants (HAP) from both new and existing 
major sources. Major sources of HAP are those stationary sources or 
groups of stationary sources that are located within a contiguous area 
under common control that emit or have the potential to emit 
considering controls, in the aggregate, 10 tons per year (tpy) or more 
of any one HAP or 25 tpy or more of any combination of HAP. The CAA 
requires the NESHAP to reflect the maximum degree of reduction in 
emissions of HAP that is achievable. This level of control is commonly 
referred to as MACT (for Maximum Achievable Control Technology). See 
CAA section 112(d)(2).
    The so-called MACT floor is the minimum control level allowed for 
NESHAP and is defined under section 112(d)(3) of the CAA. In essence, 
the MACT floor ensures that the standards are set at a level that 
assures that all major sources achieve the level of control at least as 
stringent as that already achieved by the better-controlled and lower-
emitting sources in each source category or subcategory. For new 
sources, the MACT floor cannot be less stringent than the emission 
control that is achieved in practice by the best-controlled similar 
source. The MACT standards for existing sources can be less stringent 
than standards for new sources, but they cannot be less stringent than 
the average emission limitation achieved by the best-performing 12 
percent of existing sources in the category or subcategory for which 
the Administrator has emissions information (where there are 30 or more 
sources in a category or subcategory).
    In developing MACT standards, we also must consider control options 
that are more stringent than the floor. We may establish standards more 
stringent than the floor based on the consideration of the cost of 
achieving the emissions reductions, any health and environmental 
impacts, and energy requirements. See CAA section 112(d)(2). We call 
these standards beyond-the-floor standards.
    We proposed NESHAP for hazardous waste combustors on April 20, 2004 
(69 FR 21198), and we published the final rule on October 12, 2005 (70 
FR 59402). The preamble for the proposed rule described the rationale 
for the proposed rule and solicited public comments. We received over 
75 public comment letters on the proposed hazardous waste combustor 
rule. Comments were submitted by industry trade associations, owners 
and operators of hazardous waste combustors, environmental groups, and 
State regulatory agencies and their representatives. We summarized the 
major public comments on the proposed rule and our responses to public 
comments in the preamble to the final rule and in a separate, 
supporting ``response to comments'' document. See 70 FR at 59426 and 
docket items EPA-HQ-OAR-2004-0022-0437 through 0445.
    Following promulgation of the hazardous waste combustor final rule, 
the Administrator received four petitions for reconsideration, pursuant 
to section 307(d)(7)(B) of the CAA, from Ash Grove Cement Company, the 
Cement Kiln Recycling Coalition (CKRC), the Coalition for Responsible 
Waste Incineration (CRWI), and the Sierra Club.\1\ Under this section 
of the CAA, the Administrator must initiate reconsideration proceedings 
with respect to provisions that are of central relevance to the rule at 
issue if the petitioner shows that it was impracticable to raise an 
objection to a rule within the public comment period or that the 
grounds for the objection arose after the public comment period but 
within the period for filing petitions for judicial review.
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    \1\ These petitions are included in the docket for this 
proposal. See items EPA-HQ-OAR-2004-0022-0516 thru 0519. EPA also 
received petitions from Ash Grove Cement Company and the CKRC, 
Continental Cement Company, and Giant Cement Holding, Inc. 
requesting that we stay the effective date of the particulate matter 
standard for new cement kilns. See items EPA-HQ-OAR-2004-0022-0521 
and 0523. In a notice published on March 23, 2006, EPA granted a 
temporary three-month administrative stay while the particulate 
matter standard is under reconsideration. See 71 FR 14655. In 
addition, five petitions for judicial review of the final rule were 
filed with the U.S. Court of Appeals for the District of Columbia 
Circuit by the following entities: Ash Grove Cement Company, CKRC, 
CRWI, the Environmental Technology Council, and the Sierra Club.
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    On March 23, 2006, EPA published a proposed rule granting 
reconsideration of one issue--the particulate matter (PM) standard for 
new cement kilns--raised in the petitions of Ash Grove Cement Company 
and CKRC. See 71 FR 14665. We intend to take final action on this 
reconsideration issue as expeditiously as possible.

III. Summary of This Action

    In today's notice, we are granting reconsideration of certain 
issues raised by petitioners. We summarize below our responses to 
petitions for reconsideration and provide detailed discussions in 
Section IV of this preamble of the petitions we are granting. We also 
are today proposing other amendments to correct or clarify provisions 
of the final rule. See discussion in Section V of the preamble. We also 
are presenting revised pictorial time lines (from those provided in the 
final rule) that highlight various milestones of the MACT compliance 
process. See discussion in Section VI of the preamble. Finally, we are 
providing advance notice of technical corrections that we plan to 
promulgate when we take final action on the amendments proposed today. 
See discussion in Section VI below.
    We are granting reconsideration of several issues (that are of 
central relevance to the rule's outcome) raised by Sierra Club, the 
Cement Kiln Recycling Coalition (CKRC),\2\ and the Coalition for 
Responsible Waste Incineration (CRWI). Accordingly, we are requesting 
comment on specific provisions of Subpart EEE of 40 CFR part 63: (1) 
Subcategorization of liquid fuel boilers; (2) correcting total chlorine 
emissions data below 20 ppmv; (3) use of PS-11 as a reference to 
develop alarm set-point extrapolation procedures for particulate matter 
detection systems

[[Page 52627]]

(PMDS); (4) approach to identify the best performing single source when 
two or more sources are tied for the lowest aggregate SRE/feedrate 
score; (5) beyond-the-floor analyses to consider multiple HAP that are 
controlled by a single control mechanism; (6) use of post-proposal data 
to identify the dioxin/furan standard for incinerators with dry air 
pollution control devices or waste heat boilers; and (7) three 
provisions of the health-based compliance alternative for total 
chlorine. See discussion of these topics in Section IV below.
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    \2\ Ash Grove Cement Company also submitted to EPA a petition 
for reconsideration. Ash Grove Cement's petition incorporated by 
reference the petition of the CKRC.
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    We are proposing changes to several other provisions in light of 
petitioners' concerns or upon our own review, and also are requesting 
comment on these proposed changes.
    We are not reconsidering the remaining issues raised by Sierra Club 
and CKRC \3\ and have included in the docket to this rulemaking letters 
explaining our rationale to deny reconsideration. In summary:
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    \3\ Note that, as discussed in Section II above, we previously 
granted CKRC's request to reconsider the particulate matter standard 
for new cement kilns given that new data indicate the single best 
performing source could not achieve the new source standard. 
Accordingly, we issued a stay of the new source standard for 
particulate matter for cement kilns (71 FR 14655 (March 23, 2006)) 
and proposed to revise the new source standard for particulate 
matter for cement kilns and make corresponding revisions to the new 
source standards for incinerators and liquid fuel boilers (71 FR 
14665 (March 23, 2006)).
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    1. We deny Sierra Club's petition regarding our use of normal 
emissions data, in addition to compliance test and in-between data, in 
the regression analysis to calculate the baghouse universal variability 
factor (UVF) for particulate matter. Among other things, including 
normal data results in imputing a lower standard deviation for 
particulate matter emissions variability, rather than a higher standard 
deviation as Sierra Club incorrectly surmised.
    2. We deny CKRC's petition regarding its concern that 
subcategorizing liquid fuel boilers using a waste heating value 
criterion of 10,000 Btu/lb to distinguish between boilers that are 
burning waste entirely for energy recovery versus boilers that are 
burning waste fuels at least in part for treatment is inconsistent with 
the Agency's policy \4\ that wastes with a heating value greater than 
5,000 Btu/lb are burned for energy recovery. The 5,000 Btu/lb criterion 
for burning for energy recovery is a policy providing guidance on when 
combustors are considered to burn hazardous waste as fuel that carries 
specific regulatory implications. This criterion is not in any way 
affected by the 10,000 Btu/lb criterion for subcategorizing liquid fuel 
burners to establish MACT standards. The 10,000 Btu/lb criterion 
divides liquid fuel burners into two categories based on the heating 
value of the hazardous waste they burn, and is in no way intended to 
replace the longstanding 5,000 Btu/lb criterion for energy recovery.
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    \4\ See 48 FR at 49166-167 (March 16, 1983). Note that we 
discuss in Section IV.A.2 below that, under the policy, we presume 
wastes with a heating value of 5,000 Btu/lb or greater are burned 
for energy recovery in a boiler or industrial furnace and 
acknowledge that sources may be able to document that wastes with a 
heating value below 5,000 Btu/lb are also burned for energy recovery 
in particular situations.
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    3. We deny Sierra Club's petitions to reconsider the following 
provisions because the additional reasons we provide in the final rule 
to support the provisions, or the information we use to support the 
provision, are corroborative of information and rationales already 
presented for public comment at proposal and therefore do not justify 
reconsideration. The additional reasons embellish the rationale we 
presented at proposal, generally in response to comments.
     Use of particulate matter as a surrogate for nonenumerated 
metals;
     Use of CO/HC as a surrogate for dioxin/furan and as a 
surrogate for non-dioxin/furan organic HAP for Phase II sources
     Use of variability factors in setting MACT Floors;
     Approach to establishing the dioxin/furan standard for 
cement kilns and for incinerators equipped with a wet particulate 
matter air pollution control device or no air pollution control device;
     Subcategorization of incinerators to establish separate 
dioxin/furan standards for incinerators equipped with a dry particulate 
matter air pollution control device and those without a dry particulate 
matter air pollution control device;
     Approach to establishing the mercury standard for cement 
kilns using waste concentration data;
     Approach to evaluating a beyond-the-floor standard for 
total chlorine for cement kilns; and
     Decision not to promulgate beyond-the-floor standards for 
total chlorine for lightweight aggregate kilns and solid fuel boilers 
using dry scrubbing.
    4. We deny Sierra Club's petition that we reconsider the use of CO/
HC as surrogates for non-dioxin/furan organic HAP for Phase I sources 
in this rulemaking. As we explained at proposal, we view the carbon 
monoxide, hydrocarbon, and destruction and removal efficiency standards 
as unaffected by the Court's vacature of the September 1999 
``challenged regulations'' (see Cement Kiln Recycling Coalition v. EPA, 
255 F. 3d 855, 872 (D.C. Cir. 2001)) for Phase I sources, since these 
rules were not challenged. See 69 FR at 21221. We therefore did not 
repropose those standards, and did not consider comments that they be 
revised as part of this rulemaking.\5\
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    \5\ Sierra Club has also filed a petition for judicial review 
that challenges the use of CO/HC as a surrogate for non-dioxin/furan 
for Phase II sources. Although we believe this surrogate approach is 
appropriate, if our position is not upheld we would rethink this 
surrogate approach for Phase I sources as well because the rationale 
is the same for all hazardous waste combustor source categories.
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IV. Discussion of Issues Subject to Reconsideration

    Stakeholders who would like for us to reconsider comments they 
submitted to us previously and that are relevant to the reconsideration 
issues presented below should identify the relevant docket entry 
numbers and page numbers of their comments to facilitate expeditious 
review during the reconsideration process. We plan to take final action 
on today's reconsideration as expeditiously as possible.

A. Subcategorization of Liquid Fuel Boilers by Heating Value

    In the final rule, we redefined the liquid fuel boiler subcategory 
into two separate boiler subcategories based on the heating value of 
the hazardous waste they burn: Those that burn waste with a heating 
value below 10,000 Btu/lb, and those that burn hazardous waste with a 
heating value of 10,000 Btu/lb or greater. See 70 FR at 59422. Sources 
would shift from one subcategory to the other depending on the heating 
value of the hazardous waste burned at the time. Id. at 59476.
    Sierra Club petitioned for reconsideration stating that EPA 
developed this subcategorization approach after the period for public 
comment and, thus, did not provide notice and opportunity for public 
comment.\6\ We are granting reconsideration of this provision because 
we determined that subcategorization of liquid fuel boilers was 
appropriate in response to comments on the proposed rule, after the 
period for public comment as Sierra Club states. Furthermore, 
subcategorization significantly impacted the development of the 
emission standards for liquid fuel boilers. Consequently, we are 
accepting further comment on this approach to subcategorization but are 
not proposing to change the approach. We believe the

[[Page 52628]]

subcategorization approach is warranted for the reasons provided in the 
final rule and restate them below. Nonetheless, we are open to comment 
and will determine whether a change is warranted.
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    \6\ See letter from James Pew to Stephen Johnson, dated December 
12, 2005, Section II, docket item EPA-HQ-OAR-2004-0022-0517.
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1. Rationale for Subcategorization
    We explained in the final rule that we selected normalizing 
parameters for emission standards that best fit the input to the 
combustion device. See 70 FR at 59451. We used a thermal normalizing 
parameter (i.e., expressing the standards in terms of amount of HAP 
contributed by hazardous waste per thermal content of hazardous waste) 
where hazardous waste is being used in energy-recovery devices as a 
fuel. This avoided the necessity of subcategorizing based on unit size.
    At proposal we used the thermal emissions format for the liquid 
fuel boiler standards. See 69 FR at 21283. Commenters on the proposed 
rule pointed out, however, that some liquid fuel boilers burn lower Btu 
hazardous waste because that is the only waste available, and those 
boilers with waste that has a low heating value are, in their words, 
``penalized,'' compared to those boilers with waste that has a high(er) 
heating value. Also, since these are not commercial combustion units, 
they normally lack the opportunity to blend wastes of different heating 
values to result in as-fired high heating value fuels. If all liquid 
fuel boiler standards were normalized by hazardous waste heating value, 
sources with lower heating value waste must either reduce the mass 
concentration of HAP or increase the waste fuel heating value (or 
increase the system removal efficiency) compared to sources with wastes 
having the same mass concentration of HAP but higher heating value. See 
70 FR at 59475. These measures would be problematic, however. 
Increasing the waste fuel heating value or decreasing the mass 
concentration of HAP in the waste is generally not possible because 
boilers burn the waste generated by their facility--they are not 
commercial combustion units. Decreasing the mass emission rate of HAP 
by increasing the system removal efficiency would require boilers 
burning lower heating value waste to incur costs to control HAP mass 
emission rates to levels lower than required for boilers at facilities 
that happen to generate waste with a higher heating value.
    Moreover, the thermal normalizing parameter is not well suited for 
a hazardous waste that is not burned entirely for its fuel value. In 
cases where the lower heating value waste is burned, the boiler may be 
serving in part as a treatment device for the lower heating value 
hazardous waste. When this occurs, the better normalizing parameter is 
the unit's gas flow (a different means of accounting for sources of 
different size), where the standard is expressed as amount of HAP per 
volume of gas flow (the same normalizing parameter used for most of the 
other standards promulgated in the final rule.)
    Given these concerns, we established two subcategories among the 
liquid fuel boilers: Those burning high and those burning low heating 
value hazardous waste. The normalizing parameter for sources burning 
lower energy hazardous waste is the same parameter used for the other 
hazardous waste treatment devices, gas flow rate, so that the standard 
would be expressed as concentration of HAP per volume of gas flow (a 
concentration-based form of the standard.) The normalizing parameter 
for sources burning higher energy content hazardous waste is the 
thermal parameter used for energy recovery devices, such as cement 
kilns and lightweight aggregate kilns. For the purposes of calculating 
MACT floors, the best performers are drawn from those liquid fuel 
boilers burning lower energy hazardous waste for the lower heating 
value subcategory, and from those liquid fuel boilers burning higher 
energy hazardous waste for the higher heating value subcategory. (See 
Section 23.2 of Volume III of the Technical Support Document for more 
information.)
    Moreover, liquid fuel boilers are not irrevocably placed in one or 
the other of these subcategories. Rather, the source is subject to the 
standard for one or the other of these subcategories based on the as-
fired heating value of the hazardous waste it burns at a given time. 
Thus, when the source is burning for energy recovery, then the thermal 
emissions-based standards apply. When the source is burning at least in 
part for thermal destruction, then the concentration based standard 
apply. This approach is similar to how we have addressed the issue of 
normalization in other rules where single sources switch back and forth 
among inputs that are sufficiently different to warrant separate 
classification.
2. Selection of the Heating Value Threshold
    We next considered what an appropriate as-fired heating value would 
be for each liquid fuel boiler subcategory and adopted a value of 
10,000 Btu/lb as the threshold for subcategorization. This is 
approximately the heating value of commercial liquid fossil fuels. See 
63 FR at 33782, 33788 (June 19, 1998). It is also typical of current 
hazardous waste burned for energy recovery. Id. Moreover, EPA has used 
this value in its comparable fuel specification as a means of 
differentiating fuels from waste. See id. and Table 1 to 40 CFR 261.38, 
showing that EPA normalizes all constituent concentrations to a 10,000 
Btu/lb level in its specification for differentiating fuels from 
wastes.
    We next examined the liquid waste fuel being burned at cement kilns 
and lightweight aggregate kilns, that burn hazardous waste fuels to 
drive the process chemistry to produce products, to cross-check whether 
10,000 Btu/lb is a reasonable demarcation value for subcategorizing 
liquid fuel boilers for the purposes of this MACT. We observed that 
10,000 Btu/lb in practice is the minimum heating value (or close to the 
minimum value) found in burn tank and test report data we have for 
cement kilns and lightweight aggregate kilns.\7\ Therefore, we believe 
the cement kiln and light weight aggregate kiln data confirm that this 
is an appropriate cutpoint for subcategorizing boilers, since cement 
kilns and lightweight aggregate kilns are energy recovery devices that 
blend hazardous wastes into a consistent, high heating value fuel for 
energy recovery in their manufacturing process.
---------------------------------------------------------------------------

    \7\ The cement kiln burn tank data and test report data shows 
the minimum heating values of 9,900 and 10,000 Btu/lb, respectively, 
for the hazardous waste. The minimum lightweight aggregate kiln 
heating values for hazardous waste was 10,000 Btu/ lb, excluding the 
Norlite source.
---------------------------------------------------------------------------

    We then separated the liquid fuel boiler emissions data we had into 
two groups, sources burning hazardous waste fuel with less than 10,000 
Btu/lb and all other liquid fuel boilers, and performed separate MACT 
floor analyses. (See Sections 13.4, 13.6, 13.7, 13.8, and 22 of Volume 
III of the Technical Support Document.) We calculated concentration-
based MACT standards for these sources from their respective mercury, 
semivolatile metals, chromium, and total chlorine data.
    The regulatory language implementing this subcategorization 
approach is provided in Sec. Sec.  63.1209(l)(1)(ii), 63.1209(n)(2)(v), 
63.1209(o)(1)(ii), and 63.1217.

B. Correcting Total Chlorine (TCl) Data to 20 ppmv

    In the final rule, we corrected all the total chlorine measurements 
in the data base that were below 20 ppmv to account for potential 
systemic negative biases in the Method 0050 data. See 70

[[Page 52629]]

FR at 59427-29.\8\ Sierra Club petitioned for reconsideration stating 
that EPA corrected the total chlorine measurements in response to 
comments on the proposed rule--after the period for public comment--and 
used the corrected data to revise the total chlorine emission 
standards.\9\
---------------------------------------------------------------------------

    \8\ See also USEPA, ``Technical Support Document for HWC MACT 
Standards, Volume III: Selection of MACT Standards,'' Section 5.5, 
September 2005.
    \9\ See letter from James Pew to Stephen Johnson, dated December 
12, 2005, Section IV, docket item EPA-HQ-OAR-2004-0022-0517.
---------------------------------------------------------------------------

    We are granting reconsideration of our approach to account for 
these method biases to assess the true performance of the best 
performing sources. Reconsideration is appropriate because, as Sierra 
Club states, we determined to correct the total chlorine data after the 
period for public comment on the proposed rule, and correcting the data 
significantly impacted the development of the total chlorine emission 
standards.
    To account for the bias in the method, we corrected all total 
chlorine emissions data that were below 20 ppmv to 20 ppmv. We 
accounted for within-test condition emissions variability for the 
corrected data by imputing a standard deviation that is based on a 
regression analysis of run-to-run standard deviation versus emission 
concentration for all data above 20 ppmv. This approach of using a 
regression analysis to impute a standard deviation is similar to the 
approach we used to account for total variability (i.e., test-to-test 
and within test variability) of PM emissions for sources that use 
fabric filters.
    Under today's reconsideration notice, we are accepting further 
comment on this approach to address method bias but are not proposing 
to change the approach. We believe this data correction approach is 
warranted for the reasons provided in the final rule and restate them 
below. Nonetheless, we are open to comment and will determine whether a 
change is warranted.
1. Effect of Moisture Vapor
    Commenters on the proposed rule implied that stack gas with high 
levels of gas phase water vapor will inherently have the potential to 
be biased low, particularly at emissions less than 20 ppmv. We 
concluded that there is no basis for claiming that water vapor, per se, 
causes a bias in SW-846 Method 0050 or its equivalent, Method 26A. 
Condensed moisture (i.e., water droplets), however, can cause a bias 
because it can dissolve hydrogen chloride in the sampling train and 
prevent it from being captured in the impingers if the sampling train 
is not properly purged. Water droplets can potentially be present due 
to entrainment from the wet scrubber, condensation in cooler regions of 
the stack along the stack walls, and entrainment from condensed 
moisture dripping down the stack wall across the inlet duct opening.
    Although Method 0050 addresses the water droplet issue by use of a 
cyclone and 45 minute purge, a study by Steger \10\ concludes that a 45 
minute purge is not adequate to evaporate all water collected by the 
cyclone in stacks with a total moisture content (vapor and condensed 
moisture) of 7 to 9%. At those moisture levels, Steger documented the 
negative bias that commenters reference. See 70 FR at 59427. Steger's 
recommendation was to increase the heat input to the sample train by 
increasing the train and filter temperature from 120 [deg]C (248 
[deg]F) to 200 [deg]C (392 [deg]F). We agree that increasing the probe 
and filter temperature will provide a better opportunity to evaporate 
any condensed moisture, but another solution to the problem is to 
require that the post-test purge be run long enough to evaporate all 
condensed moisture. That is the approach used by Method 26A, that EPA 
promulgated after Method 0050, and that sources must use to demonstrate 
compliance with the final standards. Method 26A uses an extended purge 
time rather than elevating the train temperature to address condensed 
moisture because that approach can be implemented by the stack tester 
at the site without using nonstandard equipment.
---------------------------------------------------------------------------

    \10\ Steger, J.L., et al., ``Laboratory Evaluation of Method 
0050 for Hydrogen Chloride'', Proc of 13th Annual Incineration 
Conference, Houston, TX, May 1994.
---------------------------------------------------------------------------

    We attempted to quantify the level of condensed moisture in the 
Steger study and to compare it to the levels of condensed moisture that 
may be present in hazardous waste combustor stack gas. This would 
provide an indication if the bias that Steger quantified with a 45 
minute purge might also be applicable to some hazardous waste 
combustors. We concluded that this comparison would be problematic, 
however, because: (1) Given the limited information available in the 
Steger paper, it is difficult to quantify the level of condensed 
moisture in his gas samples; and (2) we cannot estimate the levels of 
condensed moisture in hazardous waste combustor stack gas because, even 
though condensed moisture may have been present during a test, method 
protocol is to report the saturation moisture level only (i.e., the 
amount of water vapor present), and not the total moisture content 
(i.e., both condensed and vapor phase moisture).
    We did conclude, however, that, if hazardous waste combustor stack 
gas were to contain the levels of condensed moisture present in the gas 
that Steger tested, the 45 minute purge required by Method 0050 would 
not be sufficient to avoid a negative bias. We also concluded that this 
is potentially a practical issue and not merely a theoretical concern 
because, as commenters note, hazardous waste combustors that use wet 
scrubbers are often saturated with water vapor that will condense if 
the flue gas cools.
2. Data From Wet Stacks When a Cyclone Was Not Used
    The data for total chlorine underlying EPA's proposal came 
exclusively from compliance testing. Commenters on the proposed rule 
stated that Method 0050 procedures for addressing water droplets 
(adequate or not, as discussed above) were not followed in many cases 
because a low bias below 20 ppmv was not relevant to demonstrating 
compliance with standards on the order of 100 ppmv. We do not know 
which data sets may be problematic because, as previously stated, the 
moisture concentration reported was often the saturation (vapor phase 
only) moisture level and not the total (vapor and liquid) moisture in 
the flue gas. We also have no documentation that a cyclone was used--
even in situations where the moisture content was documented to be 
above the dew point. We therefore concluded that all data below 20 ppmv 
from sources controlled with a wet scrubber are suspect and should be 
corrected.
3. Potential Bias Due to Filter Affinity for Hydrogen Chloride
    Studies by the American Society of Testing and Materials indicate 
that the filter used in the Method 0050 train (and the M26/26A trains) 
may adsorb/absorb hydrogen chloride and cause a negative bias at low 
emission levels. (See ASTM D6735-01, section 11.1.3 and ``note 2'' of 
section 14.2.3.) This inherent affinity for hydrogen chloride can be 
satisfied by preconditioning the sampling train for one hour. None of 
the tests in our database were preconditioned in such a manner.
    We are normally not concerned about this type of bias because we 
would expect the bias to apply to all sources equally (e.g., wet or dry 
gas) and for all subsequent compliance tests. In other words, we are 
ordinarily less concerned if a standard is based on biased data, as 
long as the means by which the standard was developed and the means

[[Page 52630]]

of compliance would experience identical bias (since the level of 
control would be reflected accurately). However, because we corrected 
the wet gas measurements below 20 ppmv to address the potential low 
bias caused by condensed moisture, this correction also corrected for 
any potential bias caused by the filter's inherent affinity for 
hydrogen chloride. This resulted in a data set that is only partially 
corrected for this issue--sources with wet stacks were corrected for 
this potential bias while sources with dry stacks were not corrected. 
To address this unacceptable mix of potentially biased and unbiased 
data (i.e., dry gas data biased due to affinity of filter for hydrogen 
chloride and wet gas data corrected for condensed moisture and affinity 
of filter for hydrogen chloride), we also corrected total chlorine 
measurements from dry gas stacks (i.e., sources that do not use wet 
scrubbers).
4. Deposition of Alkaline Particulate on the Filter
    Commenters on the proposed rule were also concerned that hydrogen 
chloride may react with alkaline compounds from the scrubber water 
droplets that are collected on the filter ahead of the impingers. 
Commenters suggested this potential cause for a low bias at total 
chlorine levels below 20 ppmv is another reason not to use measurements 
below 20 ppmv to establish the standards. Although alkaline particulate 
deposition on the method filter causing a negative bias is a much 
greater concern for sources that have stack gas containing high levels 
of alkaline particulate (e.g., cement kilns, sources equipped with dry 
scrubbers), we agreed with commenters that this may be of concern for 
all sources equipped with wet scrubbers. Our approach to correct all 
data below 20 ppmv addressed this concern.
5. Decision Unique to Hazardous Waste Combustors
    We note that the rationale for correcting total chlorine data below 
20 ppmv to account for the biases discussed above is unique to the 
hazardous waste combustor MACT rule. Some sources apparently did not 
follow Method 0050 procedures to minimize the low bias caused by 
condensed moisture for understandable reasons. Even if sources had 
followed Method 0050 procedures to minimize the bias (i.e., cyclone and 
45 minute purge) there still may have been a substantial bias because 
of insufficient purge time, as Steger's work may indicate. We note that 
the total chlorine stack test method used by sources other than 
hazardous waste combustors--Method 26A--requires that the cyclone and 
sampling train be purged until all condensed moisture is evaporated. We 
believed it was necessary to correct our data below 20 ppmv data 
because of issues associated exclusively with Method 0050 and how it 
was used to demonstrate compliance with these sources.
6. Determining Variability for Data at 20 ppmv
    Correcting those total chlorine data below 20 ppmv to 20 ppmv 
brought about a situation identical to the one we confronted with 
nondetect data. See 70 FR at 59464-66. The corrected emissions data for 
the MACT pool of best performing source(s) were now generally the same 
values--20 ppmv. This had the effect of understating the variability 
associated with these data. To address this concern, we took an 
approach similar to the one we used to determine variability of PM 
emissions for sources equipped with a fabric filter. In that case, we 
performed a linear regression on the data, charting variability against 
emissions, and used the variability that resulted from the linear 
regression analysis as the variability for the sources' average 
emissions. In this case, most or all of the incinerator and liquid fuel 
boiler sources in the MACT pool had (corrected) average emissions of 
TCl at or near 20 ppmv. We therefore performed a linear regression on 
the total chlorine data charting average test condition results above 
20 ppmv against the variability associated with that test condition. 
The variability associated with 20 ppmv was the variability we used for 
incinerator and liquid fuel boiler data sets affected by the 20 ppmv 
correction.
    We also considered using the statistical imputation approach we 
used for nondetect values. See 70 FR at 59464. The statistical 
imputation approach for correcting data below 20 ppmv without dampening 
variability would involve imputing a value between the reported value 
and 20 ppmv because the ``true'' value of the biased data would lie in 
this interval. This approach would be problematic, however, given that 
many of the reported values were much lower than 20 ppmv; our 
statistical imputation approach would tend to overestimate the run to 
run variability. Consequently, we concluded that a regression analysis 
approach would be more appropriate. A regression analysis is 
particularly pertinent in this situation because: (1) We consider data 
above 20 ppmv used to develop the regression to be unbiased; and (2) 
all the corrected data averages for which we imputed a standard 
deviation from the regression curve are at or near 20 ppmv. Thus, any 
potential concern about downward extrapolation from the regression was 
minimized.
    We note that, although a regression analysis is appropriate to 
estimate run-to-run variability for the corrected total chlorine data, 
we could not use a linear regression analysis to address variability of 
nondetect values. To estimate a standard deviation from a regression 
analysis, we would need to know the test condition average emissions. 
This would not be feasible, however, because some or all of the run 
measurements for a test condition are nondetect. In addition, we were 
concerned that a regression analysis would not accurately estimate the 
standard deviation at low emission levels because we would have to 
extrapolate the regression downward to levels where we have few 
measured data (i.e., data other than nondetect). Moreover, the 
statistical imputation approach is more suitable for handling 
nondetects because the approach calculates the run-to-run variability 
by taking into account the percent nondetect for the emissions for each 
run.\11\ A regression approach would be difficult to apply particularly 
in the case of test conditions containing partial nondetects or a mix 
of detect and nondetect values. Given these concerns with using a 
regression analysis to estimate the standard deviation of test 
conditions with runs that have one or more nondetect (or partial 
nondetect) measurements, we concluded that the statistical imputation 
approach best assures that the calculated floor levels account for run-
to-run emissions variability.
---------------------------------------------------------------------------

    \11\ For multi-constituent HAP (e.g., semi-volatile metals) the 
emissions for a run could be comprised of fully detected values for 
some HAP and detection limits for other HAP that were nondetect.
---------------------------------------------------------------------------

C. Use of PS-11 and Procedure 2 as Guidance for Extrapolating the Alarm 
Set-Point of a Particulate Matter Detection System (PMDS)

    Petitioner CKRC asks that EPA reconsider its references to 
Performance Specification 11 (PS-11) and Procedure 2 in the particulate 
matter detection system (PMDS) provisions of the final rule. We are 
granting reconsideration because we developed the procedures for 
extrapolating the alarm set-point for PMDS, that included references to 
PS-11 and Procedure 2, in response to comments on the proposed rule and 
after the period for public comment. See 70 FR at 59490.

[[Page 52631]]

    CKRC also states that the reference to PS-11 for particulate matter 
CEMS (40 CFR part 60, appendix B) and Procedure 2 (Appendix F, Part 60) 
for use as guidance to implement provisions to extrapolate the alarm 
set-point of a PMDS may effectively prevent its members from utilizing 
this option due to significant technical difficulties and excessive 
costs.\12\ See Sec.  63.1206(c)(9)(iii)(B). CKRC further states that 
PS-11 and Procedure 2 contain a number of problems as they would apply 
to cement kilns. CKRC's petition does not identify any such problems or 
technical difficulties, however, and only notes that it has filed a 
petition for review in the U.S. Court of Appeals for the D.C. Circuit 
challenging EPA's final rule adopting PS-11 and Procedure 2, which case 
is being held in abeyance.
---------------------------------------------------------------------------

    \12\ See letter from David P. Novello to Stephen L. Johnson 
regarding ``Petition for Reconsideration of Certain Provisions of 
Hazardous Waste Combustor MACT Replacement Standards Rule,'' dated 
December 9, 2005, p. 9, docket item EPA-HQ-OAR-2004-0022-0520.
---------------------------------------------------------------------------

    Finally, CKRC states that use of a regression analysis approach to 
extrapolate the alarm set-point is not justified or necessary to 
establish an approximate correlation between the particulate matter 
detector system response and particulate matter concentrations. CKRC 
suggests that an alternative approach would be based on a linear 
relationship passing through zero and the mean of the PM comprehensive 
performance test results.
    When we reviewed the procedures in the final rule for establishing 
the set-point in light of CKRC's concerns regarding use of a regression 
analysis to extrapolate the set-point and use of PS-11 and Procedure 2 
as guidance, we identified several shortcomings of the final rule: (1) 
More than the required five test runs would be needed to perform a 
meaningful statistical analysis of alternative correlation models to 
identify the most appropriate model; (2) a general reference to use PS-
11 and Procedure 2 as guidance is overly broad given that those 
provisions pertain to PM continuous emissions monitors (CEMS) and would 
not be applicable to PMDS absent a specific PMDS requirement; and (3) 
the final rule contemplated establishing the set-point after the 
comprehensive performance test and, thus, did not provide for 
operations under the Documentation of Compliance. Consequently, we are 
today proposing to revise the provisions for establishing the alarm 
set-point by extrapolation by: (1) Adding procedures to establish the 
alarm set-point for operations under the Documentation of Compliance; 
(2) revising procedures to extrapolate the alarm set-point for 
operations under the Notification of Compliance; and (3) providing 
specific rather than generic references to PS-11 and Procedure 2 
provisions that must be followed to extrapolate the alarm set-point.
1. Summary of the PMDS Provisions in the Final Rule
    The final rule established revised procedures for establishing the 
alarm set-point if you elect to use a particulate matter detector 
system (PMDS) in lieu of site-specific operating parameter limits for 
compliance assurance \13\ for sources equipped with electrostatic 
precipitators and ionizing wet scrubbers, and in lieu of a bag leak 
detection system for sources equipped with a baghouse. See 70 FR at 
59424 and 59490-91, and Sec.  63.1206(c)(9).\14\ The rule explicitly 
allows you to maximize controllable operating parameters during the 
comprehensive performance test to account for emissions variability by, 
for example, detuning the air pollution control device (APCD) or 
spiking ash to establish an alarm set-point that should be routinely 
achievable considering controllable parameters. If you elect to use a 
PMDS, the rule requires you to establish the set-point either as the 
average of the test condition run average detector responses during the 
comprehensive performance test or as the extrapolation of the detector 
response after approximating the correlation between the detector 
response and particulate matter emission concentrations. You may 
extrapolate the detector response up to a response value that 
corresponds to 50% of the particulate matter emission standard or 125% 
of the highest particulate matter concentration used to develop the 
correlation, whichever is greater. To establish an approximate 
correlation of the detector response to particulate matter emission 
concentrations, the rule recommends that you use as guidance 
Performance Specification-11 for particulate matter CEMS (40 CFR part 
60, appendix B), except that you need conduct only 5 runs to establish 
the initial correlation rather than a minimum of 15 runs required by 
PS-11. The final rule also recommends that, for quality assurance, you 
should use Procedure 2 of Appendix F, Part 60, and the manufacturer's 
recommended procedures for periodic quality assurance checks and tests, 
except that: (1) You must conduct annual Relative Response Audits as 
prescribed by Procedure 2; and (2) you need only conduct Relative 
Response Audits on a 3-year interval after passing two sequential 
annual Relative Response Audits.
---------------------------------------------------------------------------

    \13\ That is, assurance of compliance with the PM emission 
standard by continuous monitoring of a surrogate parameter--PMDS 
detector response in this case--for PM emission concentrations.
    \14\ See also USEPA, ``Technical Support Document for HWC MACT 
Standards, Volume IV: Compliance with the HWC MACT Standards,'' 
September 2005, Appendix C.
---------------------------------------------------------------------------

2. Proposed Procedures To Establish the Set-Point for Operations Under 
the Documentation of Compliance
    The final rule was silent on how to establish the set-point for 
operations under the Documentation of Compliance (i.e., in the interim 
between the compliance date and submission of the Notification of 
Compliance subsequent to the comprehensive performance test). Under 
today's proposal, we would add a new provision that requires you to 
obtain a minimum of three pairs of reference method data and PMDS data, 
establish a zero point correlation value, and assume a linear 
correlation model to extrapolate the alarm set point as the PMDS 
response that corresponds to a PM concentration that is 50% of the PM 
emission standard or 125% of the highest PM concentration used to 
develop the correlation, whichever is greater. The extrapolated 
emission concentration could not exceed the PM emission standard.
    This is a reasonable approach to establish an interim set-point for 
operations prior to conducting the comprehensive performance test to 
document compliance with the emission standards. Requiring the 
additional testing needed to obtain enough test runs to identify the 
actual correlation mode--approximately 12 test runs--would discourage 
use of PMDS because of the cost of the additional testing. This is 
undesirable because a PMDS should provide better compliance assurance 
than the alternatives of operating parameter limits for electrostatic 
precipitators (ESPs) and ionizing wet scrubbers (IWSs) and a bag leak 
detection system for fabric filters, even if the PMDS is only 
approximately correlated with PM concentrations.\15\ In addition, we 
note that the actual correlation model that best fits the combustor/
PMDS may in fact be linear or a concave down polynomial, logarithmic, 
exponential, or power correlation where PM

[[Page 52632]]

concentrations increase less rapidly than the PMDS response (i.e., such 
that assuming a linear correlation would be conservative). 
Alternatively, the actual, best-fit correlation model may be nonlinear 
and concave up such that a linear correlation assumption would not be 
conservative. We specifically request comment on the extent that this 
is problematic and approaches to address the issue.
---------------------------------------------------------------------------

    \15\ See discussion of the limitations of operating parameter 
limits for ESPs and IWSs and bag leak detection systems for fabric 
filters (76 FR at 21346-47).
---------------------------------------------------------------------------

    The rule would require you to extrapolate from the average of the 
test condition run averages rather than from the highest run of the 
test condition given that the runs were intended to replicate 
controllable operating conditions. This would also provide a more 
conservative extrapolation that is appropriate given that you would 
assume a linear correlation model, as discussed above.
    The rule would allow you to include a zero point correlation value 
that you establish under procedures in Section 8.6 (5) of Performance 
Specification-11 for PM CEMS (40 CFR part 60, appendix B). Use of a 
zero point correlation value is necessary to establish a linear 
correlation given that only three test runs would be required and is 
consistent with PM CEMS correlation procedures.
    In addition, the rule would allow you to use existing paired PM 
emissions data and PMDS data that you may have. For example, if you 
operate a COMS that meets the detection limit requirements of paragraph 
(c)(9)(i)(A) and have continuous opacity monitoring system (COMS) 
response data for PM test runs, you may use those data pairs to 
establish a linear correlation to identify the initial set-point. To 
help ensure that the data are representative of the current design and 
operating conditions of the combustor and PMDS, the rule would require 
that: (1) The data be no more than 60 months old consistent with the 
data in lieu provisions of Sec.  63.1207(c)(2); and (2) the design and 
operation of the combustor or PMDS must not have changed in a manner 
that may adversely affect the correlation of PM concentrations and PMDS 
response.
    Finally, you would extrapolate the alarm set point to the PMDS 
response that corresponds to a PM concentration that is 50% of the PM 
emission standard or 125% of the highest PM concentration used to 
develop the correlation, whichever is greater. Of course, the 
extrapolated emission concentration must not exceed the PM emission 
standard. Allowing this level of extrapolation is consistent with PS-11 
procedures where the range of a PM CEMS is up to 125% of the highest PM 
concentration used to develop the correlation. The range of the CEMS 
for low emitting sources (i.e., defined by Section 3.16 of PS-11 
generally as sources that do not emit PM at concentrations that exceed 
50% of the PM standard during the most recent performance test or on a 
daily average) is the greater of 50% of the PM standard or 125% of the 
highest PM concentration used to develop the correlation.
3. Revised Procedures To Extrapolate the Alarm Set-Point for Operations 
Under the Notification of Compliance
    The final rule allowed you to establish the set-point following the 
comprehensive performance test as the average of the test run average 
PMDS response or by extrapolation. See Sec.  63.1206(9)(ii and iii). 
Under the extrapolation option, you would use PS-11 and Procedure 2 as 
guidance to identify the most appropriate correlation model based on 
five correlation tests.
    In retrospect, we now conclude (subject to consideration of 
comment) that it would be difficult to use PS-11 procedures to evaluate 
correlation models with only five correlation tests (plus a zero point 
correlation value) to identify the most appropriate model to use for 
extrapolating the set-point. The statistical criteria (i.e., confidence 
interval half range percentage, tolerance interval half range 
percentage, and correlation coefficient) used to evaluate alternative 
correlation models \16\ are directly affected by the number of test 
runs. With very few test runs, the confidence and tolerance intervals 
would be relatively high and the correlation coefficient would be 
relatively low as an artifact of the statistical procedures such that 
it would be difficult to draw conclusions from the analyses. For 
example, the rate of decrease of the statistical factors used to 
calculate the confidence and tolerance intervals slows substantially at 
10 degrees of freedom and greater, that corresponds to 12 or more test 
runs. For 12 test runs, the value of the t-statistic provided in Table 
1 of PS-11 for the half range of the 95 percent confidence interval for 
the mean PM concentration would be 2.228 while for 5 test runs and 15 
test runs the t-statistic would be 3.182 and 2.160, respectively. See 
Table 1 in PS-11.
---------------------------------------------------------------------------

    \16\ Alternative correlation models are: linear, polynomial, 
logarithmic, exponential, and power function. See Section 12.3 of 
PS-11.
---------------------------------------------------------------------------

    Given that, as just shown, a minimum of 12 test runs \17\ over the 
range of PM concentrations would generally be needed to use the PS-11 
procedures to identify the best correlation model, we considered 
requiring an additional eight test runs during the comprehensive 
performance test campaign to provide a pool of 12 paired (i.e., PMDS 
response and PM concentration) data point: Three test runs and a zero 
point used for the Documentation of Compliance extrapolation; three 
test runs from the comprehensive performance test to document 
compliance with the PM standard; and an additional five test runs over 
a range of operating conditions during the comprehensive performance 
test campaign. We are concerned, however, that requiring the additional 
five test runs over the range of operating conditions could be a 
disincentive to implement a PMDS in lieu of establishing operating 
parameter limits for ESPs and IWSs and using a bag leak detector system 
for fabric filters.\18\ In addition to the cost of the five additional 
test runs, you would need to take measures to vary PM concentrations 
during the testing to provide useful correlation data, that could be 
problematic (i.e., cost would be incurred for modifications to design 
or operations) for some sources.
---------------------------------------------------------------------------

    \17\ This actually means 12 data points which could be comprised 
of 11 test runs and a zero point correlation value.
    \18\ Note that, if you nonetheless happen to obtain a minimum of 
12 paired data points (e.g., from current or historical testing 
within 60 months of the compliance date) that provide a range of 
``as found'' and compliance test-level PM concentrations, the rule 
would require that you use PS-11 procedures to identify the most 
appropriate correlation model rather than to assume a linear model.
---------------------------------------------------------------------------

    We considered whether it would be reasonable to continue with the 
approach used for the Documentation of Compliance--to assume a linear 
regression model given the burden of obtaining enough paired data to 
identify the most appropriate correlation model. There would now be 
seven paired data available to define the linear regression: the three 
test runs and zero point from the Documentation of Compliance combined 
with the three PM comprehensive performance test runs. We are 
concerned, however, that the additional comprehensive performance test 
data may provide little improvement in defining the linear regression 
because those new data would likely be in the same PM concentration 
range as the nonzero point test runs used for the Documentation of 
Compliance--emissions that represent the high end of the range of 
controllable emissions variability.

[[Page 52633]]

    Consequently, we have tentatively concluded that three additional 
test runs at ``as found'' (i.e., normal) operating conditions and PM 
concentrations at some point during the comprehensive performance test 
campaign \19\ should be required to expand the range and number of data 
pairs to better define the assumed linear regression. This would 
provide a pool of 10 data pairs: three test runs and a zero point used 
for the Documentation of Compliance extrapolation; three test runs from 
the comprehensive performance test to document compliance with the PM 
standard; and three test runs under ``as found'' operations.\20\
    We are proposing that you would use the linear regression defined 
by these 10 paired data to extrapolate the alarm set-point to a 
response value that corresponds to 50% of the PM emission standard or 
125% of the highest PM concentration used to develop the correlation, 
whichever is greater. It is reasonable to extrapolate from the highest 
PM concentration in the correlation rather than the average of the test 
condition averages (for the comprehensive performance test) as would be 
required under the Documentation of Compliance because the additional 
data pairs, and especially the ``as-found'' data pairs, better define 
the linear regression and remove some uncertainty in the extrapolation.
---------------------------------------------------------------------------

    \19\ The ``as-found'' test runs would be conducted during the 
general time frame of the comprehensive performance test: before, in 
between, or after comprehensive performance test runs.
    \20\ If you operate a COMS that meets the detection limit 
requirements of paragraph (c)(9)(i)(A) and have a minimum of three 
data pairs under ``as found'' operations (or operations that result 
in a substantial range of PM concentrations) that were obtained 
within 60 months of the compliance date, you must use those data to 
better define the linear regression used to extrapolate the set-
point for the Documentation of Compliance. You would not be 
required, however, to conduct additional ``as found'' testing during 
the comprehensive performance test campaign.
---------------------------------------------------------------------------

    We considered whether removing the zero point correlation value may 
improve the accuracy of the regression given that you would be assuming 
a linear regression when the relationship between PMDS response and PM 
concentrations may actually follow another model (e.g., logarithmic). 
If the regression is in fact nonlinear, using only those data pairs in 
the high end of the PM concentrations range--in the range of ``as-
found'' PM concentrations to performance test concentrations--may 
better estimate through linear extrapolation the PMDS response at 
higher PM concentrations. For situations where the correlation may be 
nonlinear and concave up, retaining the zero point in the analysis may 
result in a lower slope and thus a nonconservative (i.e., too high) 
extrapolated set-point. We also considered, however, that if the PM 
concentration range represented by the data pairs was not substantial, 
deleting the zero point may introduce substantial additional 
uncertainty in the regression. Therefore, we initially conclude that 
the zero point should be retained to define the linear correlation. 
Nonetheless, we specifically request comment on this issue.
4. Revising the Initial Notification of Compliance Set-Point 
Established by Extrapolation
    The extrapolated alarm set-point established in the initial 
Notification of Compliance would be an interim extrapolated set-point. 
We are proposing that you must revise the alarm set-point after each 
Relative Response Audit (RRA).\21\
---------------------------------------------------------------------------

    \21\ Note that the rule continues to require you to conduct 
annual RRAs as prescribed by Procedure 2, except that you need only 
conduct RRA on a 3-year interval after passing two sequential annual 
RRA. A RRA is performed by collecting three PMDS and PM 
concentration pairs for ``as-found'' source operating conditions and 
PM concentrations.
---------------------------------------------------------------------------

    After the initial RRA, you would have a pool of a minimum of 13 
data pairs \22\ that should be enough to use PS-11 procedures under 
Sections 12.3 and 12.4 to identify the most appropriate correlation 
model rather than continuing to assume a linear correlation. Note that 
the PMDS would not need to meet the PS-11 performance specifications. 
The PMDS is used for compliance assurance and is not a PM CEMS that 
would be used for compliance monitoring. Nonetheless, the statistical 
criteria for evaluating the correlation for a PM CEMS are also 
applicable to evaluating the correlation for a PMDS, and the criteria 
can be compared for alternative correlation models to the PM CEMS 
specifications in Section 13.2 of PS-11 to identify the most 
appropriate correlation model.
---------------------------------------------------------------------------

    \22\ The 13 data pairs would be comprised of: three test runs 
and a zero point used for the Documentation of Compliance 
extrapolation; six test runs for the initial Notification of 
Compliance extrapolation comprised of three test runs from the 
comprehensive performance test to document compliance with the PM 
standard and three test runs under ``as found'' operations; and 
three test runs under ``as-found'' operations for the initial RRA.
---------------------------------------------------------------------------

5. Specific Rather Than Generic References to PS-11 and Procedure 2
    The final rule stated that you should use PS-11 as guidance to 
establish a correlation and Procedure 2 for quality assurance. In 
retrospect, we believe that those references are overly broad and could 
result in a permitting authority inappropriately applying provisions 
applicable to PM CEMS to a PMDS. Consequently, we propose to provide 
specific references to PS-11 and Procedure 2 where compliance with 
particular provisions would be required. Examples are the requirement 
to use Section 12.3 procedures of PS-11 to characterize alternative 
correlation models and Sections 12.4 and 13.2 procedures to identify 
the most appropriate correlation model.
    With respect to Procedure 2, there are many quality assurance 
requirements for PM CEMS that are not appropriate for a PMDS, including 
absolute correlation audits and response correlation audits. 
Accordingly, we are proposing to require compliance with specific 
Procedure 2 requirements rather than making a generic reference to use 
Procedure 2 as guidance.
    The Procedure 2 requirements that would apply to a PMDS are the 
requirements to perform an RRA. See Section 10.3 (6) of Procedure 2. As 
stated in the final rule, you must conduct an annual RRA, except that 
you need only conduct it on a 3-year interval after passing two 
sequential annual RRA. Today's proposal would expressly require you to 
comply with the provisions of Section10.4 (6) that establish the 
criteria for passing a RRA. Those provisions state that, if you fail 
the RRA, the PMDS is out of control.
    If the PMDS is out of control, today's proposal would also require 
you to comply with Section 10.5 of Procedure 2 that requires you to 
take corrective action until your PMDS passes the RRA criteria. If the 
RRA criteria cannot be achieved, you would not be required to perform a 
Relative Correlation Audit (RCA) as provided by Section 10.5 (1)(ii), 
however. That provision is appropriate for a PM CEMS but not a PMDS. If 
the RRA criteria cannot be achieved, today's rule would require you to 
re-establish the alarm set-point without using extrapolation as the 
average of the run averages of PMDS responses for the most recent 
comprehensive performance test to demonstrate compliance with the PM 
emission standard. See proposed paragraph (c)(9)(iii)(A).
6. Operations When the PMDS Is Malfunctioning
    When reviewing the PMDS requirements in the final rule in response 
to the reconsideration petition, we determined that the rule was silent 
on operations when the PMDS is malfunctioning because it is out of 
control or inoperable, for example. We believe it is reasonable to 
require that

[[Page 52634]]

operations when the PMDS is unavailable be considered the same as 
operations that exceed the alarm set-point given that there would be no 
information to conclude otherwise. Thus, we are proposing to require 
you to take corrective measures to correct the malfunction or minimize 
emissions, and the duration of the malfunction would be added to the 
time when the PMDS exceeds the alarm set-point. If the time of PMDS 
malfunction and exceedance of the alarm set-point exceeds 5 percent of 
the time during any 6-month block time period, you would have to submit 
a notification to the Administrator within 30 days of the end of the 6-
month block time period that describes the causes of the exceedances 
and PMDS malfunctions and the revisions to the design, operation, or 
maintenance of the combustor, air pollution control equipment, or PMDS 
you are taking to minimize exceedances.
    We also determined that the bag leak detection system (BLDS) 
requirements under Sec.  63.1209(c)(8) did not include provisions to 
address periods of time when the BLDS is malfunctioning. Accordingly, 
we are proposing to make similar revisions to the BLDS requirements.

D. Tie-Breaking Procedure for New Source Standards

    In the notice of proposed rulemaking, we described methodologies 
used to determine MACT floors for HAP, including the SRE/Feed approach 
\23\ used specifically for those HAP whose emissions can be controlled 
in part by controlling the amount of HAP in the hazardous waste fed to 
the source. See 69 FR at 21223-25. In general, the SRE/Feed methodology 
is applicable to HAP metals and chlorine. The SRE/Feed approach 
identifies the sources in our data base with the lowest hazardous waste 
feedrate of the HAP and the sources with the best system removal 
efficiency for the same HAP. The best performing sources (MACT pool) 
are those with the best combination of hazardous waste feedrate and 
system removal efficiency as determined by our ranking procedure. We 
then use the emission levels from these sources to calculate the 
emission level achieved by the average of the best performing sources. 
When determining the MACT floor for new sources, we use the emission 
level from the single source with the best combination of hazardous 
waste feedrate and system removal efficiency.
---------------------------------------------------------------------------

    \23\ SRE means system removal efficiency and is a measure of the 
percentage of HAP that is removed prior to being emitted relative to 
the amount fed to the unit from all inputs (e.g., hazardous waste, 
fossil fuels, raw materials).
---------------------------------------------------------------------------

    We also discussed how we determined which sources are included in 
the MACT pool. First, we ranked each source's hazardous waste feedrate 
against all the other sources' feedrates on a HAP-by-HAP (e.g., 
mercury) or HAP group (e.g., low volatile metals) basis. Then we 
assigned a relative rank of 1 to the source with the lowest feedrate 
level, a rank of 2 to the source with the second lowest feedrate, and 
so on. Next, we applied the same ranking procedure to each source's 
system removal efficiency for the same HAP. The source with the best 
system removal efficiency is assigned a relative rank of 1, and so on. 
Then each source's feedrate ranking score and system removal efficiency 
score were summed to obtain an SRE/Feed aggregated score. Finally, we 
arrayed the SRE/Feed aggregated scores from lowest to highest and the 
MACT pool was comprised of the required number of sources with the 
lowest SRE/Feed aggregated scores. For new sources the MACT pool for a 
given HAP or HAP group is comprised of the single best performing 
source, that is, the source with lowest SRE/Feed aggregated score. See 
69 FR at 21224.
    In the final rule, we used the SRE/Feed methodology for determining 
MACT floors for HAP metals and total chlorine.\24\ The preamble to the 
final rule also presented a summary of our responses to significant 
comments regarding the SRE/Feed approach. See 70 FR at 59441-47. We 
also noted that two analyses for new incinerators identified multiple 
sources with identical single best SRE/Feed aggregated scores.\25\ This 
resulted in a tie for the single best performing source for the mercury 
and low volatile metals new source standards for incinerators. See 70 
FR at 59447. In these instances, we applied a tie-breaking procedure to 
identify the single best performing source and we selected the source 
with the lowest emissions (of the tied sources) as the criterion to 
break the tie.
---------------------------------------------------------------------------

    \24\ As noted in the preamble, there were a few instances where 
the SRE/Feed methodology was not used to determine the MACT floor 
for HAP metals and total chlorine. See, for example, 69 FR at 21224. 
However, we did use the SRE/Feed approach for the standards 
addressed by CRWI's petition for reconsideration.
    \25\ USEPA, ``Technical Support Document for HWC MACT Standards, 
Volume III: Selection of MACT Standards,'' September 2005, Appendix 
E, Tables ``SF-INC-HG'' and ``SF-INC-LVM.''
---------------------------------------------------------------------------

    The CRWI states that EPA's tie-breaking procedure has not been the 
subject of direct opportunity for public comment. We agree with 
petitioner CRWI. Because there were no ties for the single best 
performing source in the proposal rule, we did not discuss the concept 
of selecting the source with the lowest emissions as the criterion to 
break ties. In addition, the tie-breaking procedure (in the rare 
instances when a tie occurs) is a key step in setting standards because 
the selected directly affects the stringency of the emission standard. 
Therefore, we conclude that there was no opportunity to comment on this 
tie-breaking procedure and grant CRWI's petition for reconsideration.
    The CRWI states in their petition that EPA's decision to break the 
tie by selecting the source with the lowest emissions results in a MACT 
floor that is below (more stringent) what the other best performers of 
the tied sources are achieving.\26\ CRWI argues that selecting the 
source with the lowest emissions is inconsistent with the statutory 
mandate. Additionally, CRWI argues that relying on emission levels as 
the tie-breaker between best performing sources is inconsistent with 
EPA's MACT floor methodology because EPA adopted the SRE/Feed approach 
while rejecting an emissions-based approach.
---------------------------------------------------------------------------

    \26\ The two instances in which there was a tie for the single 
best performing source include mercury and low volatile metals for 
incinerators. The two sources tied in the mercury analysis had 
emissions, including variability (the 99th percentile upper 
prediction limit), of 8.1 and 907 ug/dscm. The low volatile metals 
MACT floor analysis included a three-way tie. The three sources had 
emissions of 23, 129, and 198 ug/dscm. See USEPA, ``Technical 
Support Document for HWC MACT Standards, Volume III: Selection of 
MACT Standards,'' September 2005, Appendix E, Tables ``SF-INC-HG'' 
and ``SF-INC-LVM.''
---------------------------------------------------------------------------

    The arguments presented in CRWI's petition for reconsideration have 
not persuaded us that our tie-breaking procedure--selecting the source 
(of the tied sources) with the lowest emissions as the single best 
performing source--was erroneous or inappropriate. We believe this 
approach is a reasonable interpretation of section 112(d)(3), that 
states the new source standard shall not be less stringent than the 
emission control that is achieved in practice by the best controlled 
similar source (``source'' being singular, not plural). Moreover, we 
believe use of the emission level as the tie-breaking criterion is 
reasonable, not only because it is a measure of control, but because we 
have already fully accounted for hazardous waste feedrate control and 
system removal efficiency in the SRE/Feed ranking methodology. To 
choose either of these factors to break the tie would give that factor 
disproportionate weight. Nevertheless, given that the tie-breaker issue 
came up between proposal and promulgation of the final rule and so has 
not been the subject of direct opportunity for public comment, in

[[Page 52635]]

today's notice of reconsideration we are requesting public comment on 
our decision to select the source (of all tied sources) with the lowest 
emissions as the single best performing source for purposes of new 
source floor determinations. In addition, we are seeking comment on 
alternative tie-breaking criteria suggested by the CRWI such as the 
single source (of the tied sources) with the best system removal 
efficiency, the single source (of the tied sources) with the worst 
system removal efficiency, or some form of averaging (e.g., the 99th 
percentile upper prediction limit) of the tied sources.
    Because we are proposing to retain the same tie-breaker procedure 
as in the final rule, the new source emission standards promulgated for 
mercury and low volatile metals under Sec.  63.1219(b)(2) and (b)(4) 
would not change.

E. Beyond-the-Floor Analyses To Consider Multiple HAP That Are 
Similarly Controlled

    In developing MACT standards, we also must determine whether 
further emission reductions are achievable using different or 
additional control technologies. We may establish standards more 
stringent than the MACT floor based on the consideration of the cost of 
achieving the emissions reductions, any non-air health and 
environmental impacts, and energy requirements. CAA section 112(d)(2). 
We call these standards beyond-the-floor standards.
    In the notice of proposed rulemaking, we evaluated beyond-the-floor 
standards for each HAP or HAP group (i.e., semivolatile metals 
comprised of lead and cadmium, low volatile metals comprised of 
arsenic, beryllium, and chromium). The beyond-the-floor evaluations 
were discussed in the preamble and presented in the technical support 
document.\27\ As explained in the technical support document, each 
beyond-the-floor analysis was done separately by HAP. For example, when 
evaluating the cost of a beyond-the-floor standard for dioxin/furans 
based on activated carbon injection, we applied the full cost of an 
activated carbon injection system to the beyond-the-floor. In a 
separate analysis, the same approach was used when evaluating a beyond-
the-floor standard for mercury based on activated carbon injection. We 
received a public comment that the beyond-the-floor analyses for 
similarly controlled HAP by a single type of control device (e.g., 
activated carbon injection) overestimate the costs for an individual 
HAP because the control system would reduce multiple HAP.\28\ The 
commenter argued that EPA may have found additional beyond-the-floor 
results acceptable had the control device costs been apportioned 
properly among the HAP.
---------------------------------------------------------------------------

    \27\ See HAP-specific discussions in preamble (69 FR at 21240-
21297). See also USEPA, ``Draft Technical Support Document for HWC 
MACT Standards, Volume V: Emissions Estimates and Engineering 
Costs,'' March 2004, Section 4.6, Appendices F and G.
    \28\ See comments of Sierra Club, docket item EPA-HQ-OAR-2004-
0022-0292, page 30.
---------------------------------------------------------------------------

    To address this comment in the final rule, we revised the beyond-
the-floor analyses to include an additional analysis evaluating 
multiple HAP that can be controlled by a single control device (i.e., 
activated carbon injection for dioxin/furans and mercury and improved 
particulate matter control for the nonvolatile metals and particulate 
matter).\29\ Noting that the first appearance of these new beyond-the-
floor analyses was in the final rule, the Sierra Club's petition for 
reconsideration argues that EPA provided no opportunity to comment on 
these analyses. We agree with petitioner Sierra Club because we 
included these additional analyses in the final rule in response to a 
public comment. Therefore, we are granting the Sierra Club's request 
for reconsideration of the beyond-the-floor analyses that are based on 
activated carbon injection and improved particulate matter control. In 
today's notice, we are providing an opportunity for public comment on 
these beyond-the-floor analyses.
---------------------------------------------------------------------------

    \29\ USEPA, ``Response to Comments on April 20, 2004 HWC MACT 
Proposed Rule, Volume I: MACT Issues,'' September 2005, pages 152-
153.
---------------------------------------------------------------------------

    In addition, after reexamining the beyond-the-floor analyses used 
in the final rule for similarly controllable HAP by a single control 
device and also the issues raised in the petition for reconsideration 
of the Sierra Club, we are proposing to revise the beyond-the-floor 
methodology. The methodology is presented in the technical support 
document supporting this rulemaking; however, a brief discussion of the 
methodology is presented below.\30\ The results of the proposed beyond-
the-floor analyses are also presented in this support document.
---------------------------------------------------------------------------

    \30\ USEPA, ``Draft Technical Support Document for HWC MACT 
Standards--Reconsideration of the Beyond-the-Floor Evaluations,'' 
July 2006.
---------------------------------------------------------------------------

    The initial step would be to identify a suite of beyond-the-floor 
standards for each HAP or HAP group for each source category or 
subcategory. The six HAP or HAP groups include dioxin/furans, mercury, 
particulate matter (as a surrogate for the unenumerated metals 
antimony, cobalt, manganese, nickel, and selenium), semivolatile 
metals, low volatile metals, and hydrogen chloride and chlorine (total 
chlorine). We call this the comprehensive beyond-the-floor analysis. 
For reasons discussed below, beyond-the-floor evaluations for carbon 
monoxide and hydrocarbons are done separately. Next we identify an air 
pollution control strategy capable of achieving the potential beyond-
the-floor standards and estimate costs of these controls using, when 
available, standardized and peer reviewed cost models developed by 
EPA.\31\ In the case of control devices that are capable of reducing 
emissions of more than one HAP or HAP group, including activated carbon 
injection (or carbon beds) and improved particulate matter control, we 
apportioned the total costs of the control device to those HAP that 
would be controlled by the technology. HAP emission reductions and non-
air quality health and environmental impacts and energy requirements 
were then estimated.
---------------------------------------------------------------------------

    \31\ USEPA, ``EPA Air Pollution Control Cost Manual,'' available 
at http://www.epa.gov/ttn/catc/products.html.
---------------------------------------------------------------------------

    We next determined whether the comprehensive beyond-the-floor 
analysis was achievable by applying the statutory factors of the cost 
of achieving the emission reductions, any non-air quality health and 
environmental impacts, and energy requirements for each HAP or HAP 
group. The cost metric we would use to consider the cost of achieving 
emissions reductions is cost-effectiveness--dollars per unit mass 
reduction (e.g., $ per ton removed), a reasonable means of assessing 
cost of control technologies and strategies. See, e.g. Husqvarna AB v. 
EPA, 254 F. 3d 195, 200 (D.C. Cir. 2001). After considering these 
statutory factors, we evaluated each of the six HAP or HAP groups of 
the comprehensive analysis to identify those beyond-the-floor standards 
where further emission reductions appear achievable. If emission 
reductions appear achievable for all six HAP or HAP groups, then we 
would propose beyond-the-floor standards for these HAP. For co-
controlled HAP, however, if some results appeared achievable while 
others did not, we conducted a subsequent analysis whereby the costs 
associated with the unachievable HAP are reapportioned to those co-
controlled HAP appearing achievable. We believe this reapportioning 
step is necessary to prevent costs of control of a co-controlled HAP 
from being diluted by costs from unachievable (too costly) reductions 
of another co-controlled HAP. Without the reapportionment of

[[Page 52636]]

costs, these costs would be assigned to a rejected beyond-the-floor 
standard.\32\ We then evaluated the beyond-the-floor results after 
reapportioning costs to the remaining co-controlled HAP to determine 
whether the further emissions reductions are achievable. This iterative 
process continues until we determine all standards appear achievable or 
no beyond-the-floor standards appear achievable. This iterative process 
for co-controlled HAP continues until all remaining co-controlled HAP 
are judged achievable or no beyond-the-floor standards appear 
achievable for co-controlled HAP.
---------------------------------------------------------------------------

    \32\ Even though costs would be reapportioned under this 
proposed approach, we note that emissions reductions from a rejected 
beyond-the-floor standard of a co-controlled HAP would remain a 
collateral benefit of other accepted co-controlled HAP.
---------------------------------------------------------------------------

    Applying this proposed methodology would yield the same results as 
the methodology used in the final rule. These are beyond-the-floor 
standards of 68 mg/dscm \33\ (0.030 gr/dscf) for existing sources and 
34 mg/dscm (0.015 gr/dscf) for new sources, and beyond-the-floor 
standards for liquid fuel boilers for the dry air pollution control 
device subcategory of 0.40 ng TEQ/dscm for existing and new sources. 
Since the standards would not change, we are not reproposing them. We 
are, however, soliciting comment on the revised methodology for 
assessing achievability of standards for co-controlled HAP.
---------------------------------------------------------------------------

    \33\ Note that we are proposing to revise this standard from 68 
mg/dscm to 69 mg/dscm in today's notice. See Section V. J below.
---------------------------------------------------------------------------

    As mentioned above, carbon monoxide and hydrocarbons \34\ are not 
included in the comprehensive beyond-the-floor analysis. While a 
beyond-the-floor technology such as activated carbon injection may 
provide additional control of certain organic hazardous air pollutants 
(HAP), we believe it is inappropriate to evaluate (under this 
comprehensive option) numerical beyond-the-floor standards for carbon 
monoxide and hydrocarbons. When complying with the current standards 
for carbon monoxide and hydrocarbons, sources can elect to comply with 
either standard (e.g., 70 FR at 59410-59411). With respect to the 
carbon monoxide standard, the use of activated carbon injection (or any 
other beyond-the-floor techniques evaluated in the comprehensive 
analysis) would not reduce or affect emissions of carbon monoxide. 
Thus, there is no way to identify a numerical emissions limit for 
carbon monoxide that would reflect potential reductions in organic HAP 
emissions because there is no direct correlation between carbon 
monoxide and emissions of organic HAP. Given that we cannot identify a 
numerical beyond-the-floor standard for carbon monoxide and given that 
the majority of sources elect to comply with the carbon monoxide 
standard rather than the hydrocarbon standard, we believe it is not 
appropriate to include carbon monoxide in the comprehensive beyond-the-
floor analysis.
---------------------------------------------------------------------------

    \34\ Carbon monoxide and hydrocarbons are widely accepted 
indicators of combustion conditions and are used (along with the 
destruction and removal efficiency standard) as surrogates to 
control emissions of nondioxin/furan organic hazardous air 
pollutants.
---------------------------------------------------------------------------

    We also have concerns about identifying a beyond-the-floor standard 
for hydrocarbons under this comprehensive option. As we document in the 
technical support document, a significant percentage of total stack 
organics (that would be measured by a hydrocarbon monitor) are not 
organic HAP (e.g., short-chain aliphatic compounds like methane, 
propane, and acetylene).\35\ We estimate that the organic HAP emissions 
comprise approximately 20% of total hydrocarbon emissions. Furthermore, 
activated carbon injection is estimated to capture only a small 
fraction--13%--of the organic HAP emissions. Thus, we estimate that the 
use of activated carbon injection would reduce organic HAP emissions by 
less than 3% on average. This estimate would allow us to identify a 
potential numerical beyond-the-floor standard for hydrocarbons that 
would reflect reductions achieved by activated carbon injection.\36\ 
However, we believe it would be inappropriate to identify a beyond-the-
floor standard as part of the comprehensive analysis because there is 
much uncertainty in the 3% estimate.\37\ Furthermore, there are 
numerous factors that affect combustion efficiency, and, subsequently, 
hydrocarbon emissions. Thus, a source may not be able to replicate its 
hydrocarbon emissions levels (and other sources may not be able to 
duplicate those emission levels) if the quantity of organic HAP that 
are amenable to capture with activate carbon injection decreases as a 
result of one of the many factors that affect combustion efficiency. 
Finally, given that very few sources elect to comply with the 
hydrocarbon standard rather than the carbon monoxide standard (a 
standard for which we cannot identify a numerical beyond-the-floor 
level based on activated carbon injection), we believe that it is more 
appropriate to present estimated reductions of organic HAP emissions 
that would result from an activated carbon injection beyond-the-floor 
option in lieu of identifying explicit beyond-the-floor standards for 
carbon monoxide and hydrocarbons.
---------------------------------------------------------------------------

    \35\ USEPA, ``Draft Technical Support Document for HWC MACT 
Standards--Reconsideration of the Beyond-the-Floor Evaluations,'' 
July 2006, Section 4.
    \36\ For example, the beyond-the-floor standard for a 
hydrocarbon MACT floor of 10 ppmv would be 9.7 ppmv.
    \37\ USEPA, ``Draft Technical Support Document for HWC MACT 
Standards--Reconsideration of the Beyond-the-Floor Evaluations,'' 
July 2006, Section 4.1.1
---------------------------------------------------------------------------

    In its petition for reconsideration, the Sierra Club also opposes 
inclusion of costs associated with the disposal of spent carbon as a 
solid and/or hazardous waste when carbon injection is used as a beyond-
the-floor control technology.\38\ We disagree because disposal costs 
are one of the many direct costs associated with operating a carbon 
injection system (as well as an example of a non-air quality health and 
environmental impact). As mentioned above, our cost estimates are based 
on standardized and peer reviewed cost models developed by EPA. Indeed, 
the ``EPA Air Pollution Control Cost Manual'' includes specific cost 
inputs for disposal costs not only for the disposal of solid waste from 
carbon adsorber systems, but also wastewater disposal costs for wet 
scrubbers for acid gas control, dust disposal cost for baghouses and 
electrostatic precipitators for particulate matter control, and waste 
liquid collection and disposal costs for wet scrubbers for particulate 
matter control.\39\ Therefore, the cost estimates presented in the 
technical support document include disposal costs for certain beyond-
the-floor controls.\40\
---------------------------------------------------------------------------

    \38\ See petition for reconsideration of the Sierra Club, docket 
item EPA-HQ-OAR-2004-0022-0517, page 26.
    \39\ USEPA, ``EPA Air Pollution Control Cost Manual,'' EPA/452/
B-02-001, January 2002, sections 3.1, 5.2, and 6.
    \40\ Nonetheless, we also conducted the comprehensive analysis 
for new sources to investigate the extent that disposal costs of 
spent activated carbon injection would impact the achievability of 
potential beyond-the-floor standards. As presented in the technical 
support document, when disposal costs are (inappropriately) 
eliminated (reduced to zero), there would be no changes to the 
conclusions proposed regarding those standards that appear 
achievable. See ``Draft Technical Support Document for HWC MACT 
Standards `` Reconsideration of the Beyond-the-Floor Evaluations,'' 
July 2006, Section 5.2.
---------------------------------------------------------------------------

    In summary, we are accepting public comment on the revised beyond-
the-floor analyses and the conclusions.

F. Dioxin/Furan Standard for Incinerators With Dry Air Pollution 
Control Devices

    We proposed to subcategorize incinerators between wet or no air 
pollution control devices and incinerators equipped with dry air 
pollution control devices or waste heat

[[Page 52637]]

boilers.\41\ See 69 FR at 21214 (This is not subcategorizing on the 
basis of an emission control technology, but rather on the basis of a 
basic difference in process). Accordingly, we proposed separate 
emission standards for each subcategory for incinerators for dioxin/
furans.\42\ 69 FR at 21240-42. The standard proposed for existing 
incinerators with dry air pollution control devices or waste heat 
boilers (the standard at issue in this discussion) was 0.28 ng TEQ/
dscm.\43\ 69 FR at 21240. As discussed in the proposal, this standard 
was based on an evaluation of compliance test emissions data of the 
MACT pool sources comprising this subcategory of incinerators. As noted 
in the petition of the Sierra Club, one of the five MACT pool sources 
was the Clean Harbors Aragonite incinerator located in Utah.\44\ The 
consideration of these data in the MACT floor analysis is the specific 
point in contention in the Sierra Club's petition for reconsideration.
---------------------------------------------------------------------------

    \41\ In its petition for reconsideration, the Sierra Club also 
petitioned EPA to reconsider the decision to subcategorize the 
hazardous waste incinerator source category. As discussed in Section 
III above, we have denied their request for reconsideration. 
Therefore, we are neither soliciting comments nor will we consider 
any comments received on the decision to subcategorize the 
incinerator category.
    \42\ Sierra Club also petitioned EPA to reconsider the dioxin/
furan standard for the subcategory of incinerators with wet or no 
air pollution control devices. This standard is not discussed in 
today's proposed rule because EPA has denied the reconsideration 
request as discussed in Section III above. Therefore, we are neither 
requesting comments nor will we consider any comments received on 
the dioxin/furan standard for incinerators with wet or no air 
pollution control devices.
    \43\ See USEPA, ``Draft Technical Support Document for HWC MACT 
Standards, Volume III: Selection of MACT Standards,'' March 2004, 
Appendix C, Table ``E-INC/D+WHB-DF.'' Note that because the issue 
raised in the Sierra Club's petition does not affect the dioxin/
furan standard for new incinerators, the scope of this discussion 
will be limited to existing incinerators.
    \44\ EPA's data base contains emissions data from Clean Harbors 
Aragonite for six different test conditions. The proposed dioxin/
furan standard was based, in part, on the trial burn data from Clean 
Harbors Aragonite that was conducted in June 2001.
---------------------------------------------------------------------------

    In the final rule, we adopted this same subcategorization scheme 
and promulgated separate dioxin/furan emissions standards for each 
subcategory of incinerators. See 70 FR at 59420, 59467. Our revised 
MACT floor analysis yielded a calculated floor level of 0.42 ng TEQ/
dscm, that reflected emissions variability. We then evaluated whether 
this calculated floor level was less stringent than the interim dioxin/
furan standard under Sec.  63.1203(a)(1). Because we concluded the 
calculated floor level of 0.42 ng TEQ/dscm was less stringent than the 
interim dioxin/furan standard, we promulgated the interim dioxin/furan 
standard as the standard.\45\ Thus, the emission standard promulgated 
for existing incinerators with dry air pollution control devices or 
waste heat boilers was either 0.20 ng TEQ/dscm or 0.40 ng TEQ/dscm 
provided that the combustion gas temperature at the inlet to the 
initial particulate matter control device is 400 [deg]F or lower (Sec.  
63.1219(a)(1)). The analyses supporting these standards are included in 
the technical support document.\46\
---------------------------------------------------------------------------

    \45\ Replacement standards can be no less stringent than 
existing standards, including the interim standards under Sec. Sec.  
63.1203-1205. See 70 FR at 59457-58.
    \46\ See USEPA, ``Technical Support Document for the HWC MACT 
Standards, Volume III: Selection of MACT Standards,'' September 
2005, Appendix E, Table ``E-INCDWHB-DF.''
---------------------------------------------------------------------------

    As discussed in the final rule, the calculated MACT floor increased 
from 0.28 ng TEQ/dscm to 0.42 ng TEQ/dscm because we were alerted in 
comments to the proposed rule that our MACT pool analysis considered 
dioxin/furan data that should not have been included. Commenters stated 
that the Clean Harbors Aragonite incinerator (source 327C10 in the data 
base) encountered problems with its carbon injection system during the 
emissions test from which the data were obtained and subsequently used 
in the MACT floor analysis for this incinerator subcategory.\47\ We 
investigated the commenters' claims after proposal and confirmed the 
problems that were encountered during testing. See 70 FR at 59419, 
59432. Importantly, we determined that these dioxin/furan emissions 
data were not used to establish operating parameter limits for the 
carbon injection system based on this test.\48\ Therefore, we no longer 
designate this test condition as ``compliance test'' data, that is the 
type of data upon which this MACT standard is based. After concluding 
that these emissions data are not appropriate for inclusion in the MACT 
floor analysis, we instead substituted in its place other readily 
available compliance test emissions data in our data base for that 
facility. While the substituted emissions data are indeed older than 
the problematic data, these data are the most recent valid compliance 
data available to us for this source. As a result of this data handling 
decision, the calculated MACT floor increased as discussed earlier.
---------------------------------------------------------------------------

    \47\ See USEPA, ``Response to Comments on April 20, 2004 HWC 
MACT Proposed Rule, Volume I, MACT Issues,'' September 2005, Section 
1.3.2, and ``Technical Support Document for the HWC MACT Standards, 
Volume III: Selection of MACT Standards,'' September 2005, Section 
10.1.1.
    \48\ See docket item EPA-HQ-OAR-2004-0022-0401.
---------------------------------------------------------------------------

    The Sierra Club notes in its petition that the promulgated MACT 
standard for this subcategory of incinerators increased from that 
proposed as a result of EPA's decision to use different dioxin/furan 
emissions data from the Clean Harbors Aragonite incinerator. The Sierra 
Club states that EPA had provided no opportunity to comment on this 
data handling decision because it was not reflected in the proposed 
rule. We agree with petitioner Sierra Club that it was impracticable 
for them to raise its concern about the use of the Clean Harbors 
Aragonite emissions data. Therefore, we are granting the Sierra Club's 
petition for reconsideration for this issue.
    The Sierra Club contends that EPA's data substitution for the Clean 
Harbors Aragonite incinerator is arbitrary and capricious because EPA 
rejected the newer test data to use older and worse test data. The 
Sierra Club states that a source encountering problems with its air 
pollution control equipment does not justify using other data from an 
earlier test with higher emissions because EPA had no reason to 
conclude that the incinerator would perform worse than the level it 
achieved while encountering problems.
    The arguments presented in the petition for reconsideration have 
not persuaded us, subject to consideration of further comment, that our 
MACT floor determination in the final rule was inappropriate. We 
believe we correctly identified the MACT floor for this incinerator 
subcategory based on the available emissions data. The Clean Harbors 
Aragonite data from 2001 cannot be used in the MACT floor analysis 
because these data simply are not representative of performance due to 
problems encountered. We note that the substituted Clean Harbors 
Aragonite data considered in the final rule MACT floor analysis were 
not included in the pool of the five best performing sources for the 
dioxin/furan standard. If we had simply excluded the problematic data 
(and not substituted the older data), then we would have promulgated 
the identical emission standard because the substituted data for Clean 
Harbors Aragonite had no direct impact on the floor analysis (i.e., the 
data were not included in the MACT pool). Nevertheless, because we 
changed the floor determination between proposal and promulgation in 
response to comments received on the proposal, and because we also made 
certain data editing decisions (again in response to public comment) 
that resulted in a different data base being used for the

[[Page 52638]]

floor determination than we used at proposal, we are requesting public 
comments on the MACT floor analysis that supported the final rule. 
Specifically, we are soliciting comment on the final rule MACT floor 
analysis that included our decision to replace the 2001 Clean Harbors 
Aragonite data with other dioxin/furan emissions data in our data base.
    Because we are proposing to retain the final rule MACT floor 
analysis for the subcategory of incinerators equipped with dry air 
pollution control devices or waste heat boilers, the emission standards 
promulgated for dioxin/furans under Sec.  63.1219(a)(1)(i) and 
(b)(1)(i) would not change (subject to consideration of public 
comment).

G. Provisions of the Health-Based Compliance Alternative

    The final rule allows you to establish and comply with health-based 
compliance alternatives for total chlorine for hazardous waste 
combustors other than hydrochloric acid production furnaces in lieu of 
the MACT technology-based emission standards established under 
Sec. Sec.  63.1216, 63.1217, 63.1219, 63.1220, and 63.1221. See 70 FR 
at 59413-19 and Sec.  63.1215.
    Sierra Club petitioned for reconsideration stating that EPA changed 
several provisions of the health-based compliance alternative after the 
period for public comment and therefore did not provide notice and 
opportunity for public comment.\49\ In addition, Sierra Club states 
that three new provisions are problematic: (1) It is unlawful to allow 
sources to comply with the health-based compliance alternative without 
prior approval from the permitting authority; (2) it is unlawful to 
allow a source to obtain an unlimited extension of the compliance date 
if their eligibility demonstration is disapproved and the source is 
unable to change the design or operation of the source to comply with 
the MACT emission standards by the compliance date; and (3) the Agency 
cannot rely on the Title V program as the vehicle for establishing 
health-based compliance alternatives.
---------------------------------------------------------------------------

    \49\ See letter from James Pew to Stephen Johnson, dated 
December 12, 2005, Section XII, docket item EPA-HQ-OAR-2004-0022-
0517.
---------------------------------------------------------------------------

    We are granting reconsideration of these provisions because we 
developed them in response to comments on the proposed rule, after the 
period for public comment as Sierra Club states. Furthermore, to 
address Sierra Club's concerns, we are proposing to revise the rule 
pertaining to these provisions as follows: (1) The rule would state 
that the operating requirements specified in the eligibility 
demonstration are ``applicable requirements'' as defined in 40 CFR 70.2 
or 71.2 and therefore must be incorporated in the Title V permit; (2) a 
source may comply with the health-based compliance alternative without 
prior approval from the permitting authority provided that the source 
has made a good faith effort to provide complete and accurate 
information and to respond to any requests for additional information; 
and (3) the compliance date extension cannot exceed one year if the 
eligibility demonstration is disapproved and the source is unable to 
change the design or operation to comply with the MACT emission 
standards by the compliance date. These provisions are discussed below.
    Note that we are accepting further comment on these provisions in 
general in addition to requesting comment on the proposed revisions to 
the provisions. We believe the provisions in general are warranted for 
the reasons provided in the final rule and restate these reasons below. 
Nonetheless, we are open to comment and will determine whether changes 
are warranted other than those we are proposing.
1. Complying With the Health-Based Compliance Alternative Without Prior 
Approval From the Permitting Authority Would Be Conditional
    The final rule does not require prior approval of the eligibility 
demonstration for existing sources. If your permitting authority has 
not approved your eligibility demonstration by the compliance date, and 
has not issued a notice of intent to disapprove your demonstration, you 
may nonetheless begin complying, on the compliance date, with the HCl-
equivalent emission rate limits and associated chlorine feedrate limits 
you present in your eligibility demonstration. See 70 FR at 59484 and 
Sec.  63.1215(e)(2)(i)(C).
    We are today providing an opportunity to comment on this provision 
in general and on a proposal to revise the rule to clarify that a time 
extension is conditioned on your making a good faith effort to submit 
complete and accurate information and to respond in a timely manner to 
any requests for additional information.
    Many commenters on the proposed rule stated that requiring prior 
approval of the eligibility demonstration would be unworkable. 
Commenters were concerned that the permitting authority may not approve 
the demonstration prior to the compliance date, even though the source 
has submitted complete and accurate information and has responded to 
any requests for additional information in good faith. A commenter 
suggested that, if the permitting authority has neither approved nor 
disapproved the eligibility demonstration by the compliance date, the 
source may begin complying on the compliance date with the alternative 
health-based limits specified in the eligibility demonstration.
    We agreed with commenters that requiring prior approval of the 
eligibility demonstration may be unworkable for the reason commenters 
suggested. Accordingly, the final rule does not require prior approval 
of the eligibility demonstration for existing sources. If your 
permitting authority has not approved your eligibility demonstration by 
the compliance date, and has not issued a notice of intent to 
disapprove your demonstration, you may nonetheless begin complying, on 
the compliance date, with the HCl-equivalent emission rate limits and 
associated chlorine feedrate limits you present in your eligibility 
demonstration.
    When reviewing this provision in response to Sierra Club's petition 
for reconsideration, we noticed that the regulatory language at Sec.  
63.1215(e)(2)(i)(C) simply stated that you could begin complying on the 
compliance date with the health-based alternative compliance 
requirements absent approval from the permitting authority if the 
permitting authority had not issued a notice of approval or intent to 
disapprove your eligibility demonstration by the compliance date. We 
inadvertently did not make the provision conditional on your making a 
good faith effort to provide complete and accurate information and to 
respond to any requests for additional information in a timely manner. 
Accordingly, we propose today to revise that regulatory provision to 
say:

     If your permitting authority has not approved your 
eligibility demonstration by the compliance date, and has not issued 
a notice of intent to disapprove your demonstration, you may begin 
complying, on the compliance date, with the HCl-equivalent emission 
rate limits you present in your eligibility demonstration provided 
that you have made a good faith effort to provide complete and 
accurate information and to respond to any requests for additional 
information in a timely manner.

    If the permitting authority believes that you have not made a good 
faith effort to provide complete and accurate information or to respond 
to any requests for additional information, the authority may notify 
you in writing by the compliance date that you have not

[[Page 52639]]

met the conditions for complying with the health-based compliance 
alternative without prior approval.
2. An Extension of the Compliance Date Granted Upon Disapproval of an 
Eligibility Demonstration Cannot Exceed One Year
    The final rule states that the permitting authority should notify 
you of approval or intent to disapprove your eligibility demonstration 
within 6 months after receipt of the original demonstration, and within 
3 months after receipt of any supplemental information that you submit. 
A notice of intent to disapprove your eligibility demonstration, 
whether before or after the compliance date, will identify incomplete 
or inaccurate information or noncompliance with prescribed procedures 
and specify how much time you will have to submit additional 
information or comply with the total chlorine MACT standards. The 
permitting authority may extend the compliance date of the total 
chlorine MACT standards to allow you to make changes to the design or 
operation of the combustor or related systems as quickly as practicable 
to enable you to achieve compliance with the total chlorine MACT 
standards. See 70 FR at 59484 and Sec.  63.1215(e)(2)(i)(B) and (D).
    We are today providing an opportunity for comment on this provision 
in general and on a proposal to revise the rule to limit the time 
extension to (up to) one year. We are tentatively persuaded by Sierra 
Club's argument that this limitation is needed to be consistent with 
CAA section 112(i)(3)(B) (and the General Provisions under Subpart A--
Sec.  63.6(i)(4)(i)(A)).
    Commenters on the proposed rule were concerned that the permitting 
authority may disapprove the eligibility demonstration for the health-
based compliance alternative too late for the source to make changes to 
the design or operation of the combustor or related systems to enable 
the source to comply with the total chlorine MACT standard. See 70 FR 
at 59484. We agreed with that concern and therefore allowed the 
permitting authority to extend the compliance date. We inadvertently 
did not limit the extension of the compliance date to one year, 
however, consistent with the General Provisions and CAA section 
112(i)(3)(B).
3. The Health-Based Compliance Alternative Requirements Are Applicable 
Requirements
    We stated in the preamble to the final rule in response to comments 
that, because the health-based compliance alternative requirements are 
clearly defined (e.g., HCl-equivalent emission limits, chlorine 
feedrate limits), and because any standards or requirements created 
under CAA section 112 are considered applicable requirements under 40 
CFR part 70, the compliance alternatives would be incorporated into 
Title V permits. See 70 FR at 59481.
    Nonetheless, petitioner Sierra Club states that the Agency cannot 
rely on the Title V program as the vehicle for establishing health-
based compliance alternatives.
    We are today providing an opportunity for comment on this provision 
in general and on a proposal to revise the rule to add clarifying 
regulatory language stating that Sec.  63.1215 requirements are 
applicable requirements under part 70 and therefore must be included in 
the Title V permit as would any other applicable requirement. We note 
that the final rule specifies that operating requirements in the 
Notification of Compliance are applicable requirements for purposes of 
parts 70 and 71 of this chapter, and that the operating requirements 
specified in the Notification of Compliance will be incorporated in the 
Title V permit. See Sec.  63.1206(c)(1)(iv)-(v). The health-based 
compliance alternative is implemented using an eligibility 
demonstration that is independent from the Notification of Compliance. 
See Sec.  63.1215(c) and (e). Accordingly, we propose today to add new 
Sec.  63.1215(e)(3) to clarify that the health-based compliance 
alternative requirements established in an approved eligibility 
demonstration are applicable requirements and must be included in the 
Title V permit.

V. Other Proposed Amendments

A. Sunset Provision for the Interim Standards

    In the preamble to the final rule (70 FR at 59503) we indicated in 
response to a comment that we were including a sunset provision for the 
interim standards in the final rule. However, that provision was 
inadvertently omitted from the rule. In today's rule we propose to 
incorporate sunset provisions into Sec. Sec.  63.1203, 63.1204, and 
63.1205. As indicated in the referenced preamble, the Interim Standards 
will be superseded by the final replacement standards on the compliance 
date for the replacement standards. See proposed additions to 
Sec. Sec.  63.1203(e), 63.1204(i), and 63.1205(e).

B. Operating Parameter Limits for Sources With Fabric Filters

    In the final rule, we promulgated a new paragraph Sec.  
63.1206(c)(8) that sets forth operating parameter limits for sources 
equipped with a baghouse (fabric filter) (70 FR at 59486). If you use a 
baghouse to comply with one or more emission standard(s), you are 
either required to use a bag leak detection system that meets the 
specifications of Sec.  63.1206(c)(8)(ii), or meet the particulate 
matter detection system requirements specified in Sec.  63.1206(c)(9). 
However, the current language of Sec.  63.1206(c)(9) appears to 
restrict the particulate matter detection system requirement to 
electrostatic precipitators and ionizing wet scrubbers. This was never 
our intent. Consequently, in today's notice we are proposing to amend 
Sec.  63.1206(c)(9) to include baghouses.

C. Confirmatory Performance Testing Not Required for Sources That Are 
Not Subject to a Numerical Dioxin/Furan Emission Standard

    Section 63.1207(b)(3) of the final rule requires a one-time only 
test for dioxin/furan emissions for those sources that are not required 
to meet a numerical dioxin/furan emission standard. You are only 
required to repeat this test if you change the design or operation of 
the source in a manner that may increase dioxin/furan emissions. 
Because dioxin/furan testing is the only component of the confirmatory 
performance test (see Sec.  63.1207(b)(2)), it logically follows that 
confirmatory performance testing is not required for these sources. 
Nevertheless, the final rule did not include an explicit exemption from 
the confirmatory performance test requirement. In today's notice, we 
are proposing to add a new paragraph (vi) to Sec.  63.1207(b)(3) to 
clarify this point.

D. Periodic Performance Tests for Phase I Sources

    Section 63.1207(d)(1) requires periodic comprehensive performance 
testing to begin no later than 61 months after commencing the previous 
comprehensive performance test. Section 63.1207(d)(2) requires 
confirmatory performance testing to begin no later than 31 months after 
commencing the previous performance test. However, in the Interim 
Standards Rule, promulgated on February 13, 2002, we added Sec.  
63.1207(d)(4) that waived these periodic test requirements under the 
interim standards (67 FR at 6815).
    Section 63.1207(d)(4) also includes language reinstating the 
periodic test requirements upon promulgation of the final replacement 
standards (i.e., October 12, 2005). Our intent was to reinstate 
periodic testing only for sources operating under the October 12, 2005 
replacement standards, not the

[[Page 52640]]

interim standards. However, the current language could also be 
misinterpreted to require periodic testing by sources that remain under 
the interim standards. In today's rule, we propose to amend Sec.  
63.1207(d) to clarify that periodic comprehensive performance testing 
and confirmatory performance testing are only required for sources 
operating under the final replacement standards. For the reasons 
discussed in the preamble to the interim standards rule (67 FR at 
6802), periodic testing is not required for sources that remain 
operating under the interim standards.

E. Performance Test Waiver for Sources Subject to Hazardous Waste 
Thermal Concentration Limits

    In the 1999 final rule (64 FR at 52828), we waived the performance 
test requirement for mercury, semivolatile metals, low volatile metals, 
or hydrogen chloride/chlorine gas for sources that demonstrated that 
the maximum theoretical emission concentration (MTEC) did not exceed 
the emission standard for that HAP. See Sec.  63.1207(m). In essence, 
this provision waives the performance test if the constituent feed rate 
(after conversion to an exhaust gas concentration using continuously 
monitored exhaust gas flow data) is less than the applicable emission 
rate, assuming that 100% of the constituent in the feed is emitted from 
the combustion unit.
    In the 2005 final rule (70 FR at 59402), for certain source 
categories (i.e., liquid fuel boilers, cement kilns, and lightweight 
aggregate kilns), we limited the feedrate of these same constituents in 
proportion to the heat input from hazardous waste. See, for example, 
Sec.  63.1217(a)(2)(ii). We refer to these as hazardous waste thermal 
concentration emission limits.\50\ In today's notice, we propose to 
amend Sec.  63.1207(m) to waive performance tests for any constituent 
whose thermal concentration in the waste feed is at or below the 
applicable thermal concentration emission limit. This is analogous to 
the performance test waiver for sources that comply with MTEC 
standards. Although performance tests would not be required, the 
thermal concentration emission limits would remain in effect during 
source operations.
---------------------------------------------------------------------------

    \50\ Note that are granting reconsideration of the decision to 
subcategorize the liquid fuel boiler source category by heating 
value, which includes standards based on this potential normalizing 
parameter. See Section IV.A above.
---------------------------------------------------------------------------

F. Averaging Method When Calculating 12-Hour Rolling Average Thermal 
Concentration Limits

    The replacement standards for cement kilns and lightweight 
aggregate kilns limit the emissions of semivolatile metals (cadmium and 
lead) and low volatile metals (arsenic, beryllium, and chromium) from 
hazardous waste feeds relative to the heating value of those feeds. In 
order to monitor compliance with those requirements, Sec.  
63.1209(n)(2)(iii) requires the source to establish a 12-hour rolling 
average feedrate limit for those metals on a thermal concentration 
(e.g., pounds per million British thermal unit) basis. The limits are 
derived from operating levels during the comprehensive performance 
test.
    For reasons discussed in the 1999 final rule (64 FR at 52922), EPA 
has consistently required sources to calculate most of their operating 
parameter limits as the average of each relevant test run average 
recorded during the comprehensive performance test. Section 
63.1209(n)(2)(iii) describes how to calculate the average thermal 
concentration of metals for each test run, but it does not explicitly 
describe how to calculate the thermal concentration limit. In today's 
notice, we are proposing to amend Sec.  63.1209(n)(2)(iii) to indicate 
that the metal thermal concentration limit is the average of the 
individual test run averages.

G. Calculating Rolling Averages for Averaging Periods in Excess of 12 
Hours

    The final rule allows operators of liquid fuel boilers to average 
certain feed rate limits over a period of up to one year. This applies 
to the mercury and semivolatile feed rate limits. Sec. Sec.  
63.1209(n)(2)(v)(A)(iv) and (n)(3)(v) as well as Sec. Sec.  
63.1209(l)(1)(ii)(B)(5) and (l)(1)(C)(5) all describe the same method 
for calculating averages of longer than 12 hours upon initial 
compliance with the rule. They require that you calculate the average 
of all 1-minute average values until you have acquired data for the 
full averaging period (i.e., up to one year). Thereafter, you are 
required to update this value each hour using the 60-minute average 
feedrate from the previous hour.
    EPA recognizes that these approaches may needlessly complicate data 
management and could require increased data storage. Therefore, we are 
proposing to amend these sections of the regulation in two ways. The 
first change will explicitly allow you to calculate long-term rolling 
averages using only the 1-minute data that you are otherwise required 
to record. If you choose this approach, you would calculate long-term 
averages in exactly the same manner as all other rolling averages, with 
the value being updated every minute. There would be no requirement to 
switch to a different system after completion of the initial averaging 
period. Alternatively, you may still choose to use the hourly update 
option specified in the current regulations. If you choose this latter 
option, however, we are proposing to allow you to begin using hourly 
updates after completing at least 12 hours of monitoring using 1-minute 
updates. (The current regulation only allows hourly updates after 
completing the first long-term averaging period, that could be up to 
one year.) We believe that this will allow you to begin ``normal'' 
monitoring operations as soon as possible without any significant 
effect on accuracy.
    We wish to emphasize that the definition of continuous monitor 
requires that you maintain all one-minute average values in your 
operating record regardless of whether you elect one-minute or hourly 
updates to the rolling average. Pursuant to Sec.  63.10(b)(1) of the 
MACT General Provisions, these data must be retained for a period of at 
least five years.

H. Calculating Rolling Averages

    Most of the feed rate, emission rate, and operating parameter 
limits established in the HWC MACT rule are monitored on a rolling 
average basis that varies from hourly to annually. Continuously 
monitored parameters must be recorded at least once each minute. The 
rolling average is then calculated as the average of the one-minute 
values for the duration of the most recent averaging period. For 
example, a one-hour rolling average temperature value would be 
calculated by averaging the 60 most recent one-minute temperature 
readings, with a new hourly rolling average value being generated every 
minute.
    In the 1999 final rule, the longest permissible rolling average 
period was 12 hours. However, in the 2005 final rule, we allowed up to 
annual averaging for those emission standards that are based on 
``normal'' feed data. (See the liquid fuel boiler standards for mercury 
and semivolatile metals under Sec.  63.1217.) In recognition of the 
fact that these long-term averages would not vary significantly over 
short time periods, we chose to allow you to update these rolling 
averages hourly, rather than every minute. Our intent was to retain 
one-minute updates for averaging periods up to 12 hours while allowing

[[Page 52641]]

hourly updates for longer averaging periods. However, we inadvertently 
specified hourly updates for several parameters that are not subject to 
long-term (i.e., greater than 12-hour) averaging. This occurred for 
three parameters: the chromium feedrate in liquid fuel boilers burning 
hazardous waste with a heating value of 10,000 Btu per pound or greater 
under Sec.  63.1209(n)(2)(v)(B)(1)(i), the chromium feedrate in liquid 
fuel boilers burning hazardous waste with a heating value of less than 
10,000 Btu per pound under Sec.  63.1209(n)(2)(v)(B)(2), and the 
chlorine thermal concentration feedrate limit for liquid fuel boilers 
burning hazardous waste with a heating value of not less than 10,000 
Btu per pound under Sec.  63.1209(o)(1)(ii)(A)(3). In today's notice, 
we are proposing to delete the hourly update references for these three 
parameters.

I. Timing of the Periodic Review of Eligibility for the Health-Based 
Compliance Alternatives for Total Chlorine

    If you choose to comply with the health-based compliance 
alternatives for total chlorine, Sec.  63.1215(h)(2)(i) requires you to 
review your eligibility under that alternative at least every five 
years. The results must be submitted to the regulatory authority for 
review and approval. However, there is some ambiguity in the exact 
timing of that submission in the current regulatory language.
    In this action, we propose to eliminate the ambiguity by amending 
Sec.  63.1215(h)(2)(i) to indicate that the results of your 5-year 
review are due to the permitting authority at the time you submit your 
comprehensive performance test plan (as specified in the current rule). 
This will most likely be approximately four years (not five, as 
indicated in the current rule) after your last comprehensive 
performance test.

J. Expressing Particulate Matter Standards Using the International 
System of Units (SI)

    In the final rule, we expressed the particulate matter standards 
for incinerators, cement kilns, and lightweight aggregate kilns using 
English units (gr/dscf) while expressing the particulate matter 
standards for liquid and solid fuel boilers using SI units (mg/dscm). 
Our preference is to express all particulate matter standards in SI 
units and we are proposing to revise the particulate matter standards 
in Sec. Sec.  63.1216 through 63.1221 by expressing the standards in SI 
units.\51\ When making the conversion from English units to SI units, 
we are proposing to convert the calculated particulate matter results 
prior to the step in which the results were rounded to two significant 
figures. For example, the calculated MACT floor for existing 
incinerators was 0.0133 gr/dscf, that was rounded to 0.013 gr/dscf (the 
latter being the promulgated standard).\52\ Thus, our proposed approach 
would convert 0.0133 gr/dscf to SI units. We believe this approach for 
converting English to SI units more accurately reflects the MACT 
standards identified in the final rule because making the conversion to 
SI units after rounding the results (in English units) can introduce 
imprecision. In addition, we also would recalculate and revise as 
necessary the liquid and solid fuel boiler standards using the same 
approach (i.e., existing solid fuel boilers and existing liquid fuel 
boilers). The table below shows the results of the conversion to SI 
units.
---------------------------------------------------------------------------

    \51\ We are not proposing to revise the particulate matter 
standards in Sec. Sec.  63.1203 thru 63.1205 because affected 
sources are already complying with these standards.
    \52\ See USEPA, ``Technical Support Document for HWC MACT 
Standards, Volume III: Selection of MACT Standards,'' September 
2005, Appendix F, Table ``APCD-INC-PM.''

                           Proposed Particulate Matter Standards Expressed in SI Units
----------------------------------------------------------------------------------------------------------------
                                                                                         Proposed  standard  in
         Source category                 Type of source         Promulgated standard            SI units
----------------------------------------------------------------------------------------------------------------
Solid Fuel Boilers (Sec.           Existing New.............  68 mg/dscm                69 mg/dscm
 63.1216).                                                    34 mg/dscm                34 mg/dscm
Liquid Fuel Boilers (Sec.          Existing New.............  80 mg/dscm                79 mg/dscm
 63.1217).                                                    20 mg/dscm                20 mg/dscm
Incinerators (Sec.   63.1219)....  Existing New.............  0.013 gr/dscf             30 mg/dscm
                                                              0.0015 gr/dscf            3.5 mg/dscm
Cement Kilns (Sec.   63.1220)....  Existing New.............  0.028 gr/dscf             65 mg/dscm
                                                              0.0023 gr/dscf            5.3 mg/dscm
Lightweight Aggregate Kilns (Sec.  Existing New.............  0.025 gr/dscf             57 mg/dscm
   63.1221).                                                  0.0098 gr/dscf            22 mg/dscm
----------------------------------------------------------------------------------------------------------------

    We acknowledge that several of the particulate matter standards 
shown in the table above may be revised as a result of the 
reconsideration of the particulate matter standard for new cement kilns 
(71 FR at 14665). If any particulate matter standards are revised, we 
would apply the same procedure to convert the new standards to SI 
units.
    Accordingly, we propose to revise the following particulate matter 
standards: Sec. Sec.  63.1216(a)(7); 63.1217(a)(7); 63.1219(a)(7) and 
(b)(7); 63.1220(a)(7)(i) and (b)(7)(i); and 63.1221(a)(7) and (b)(7).

K. Mercury Standards for Cement Kilns

    In the final rule, we intended to establish a two-pronged approach 
for controlling mercury emissions from cement kilns. See preamble 
discussion at 70 FR at 59468. Step one establishes a maximum 
concentration of mercury in the hazardous waste feed. Step two allows 
the source to choose between either a traditional approach of limiting 
the total mercury feed rate and relevant operating parameters, or a 
maximum theoretical emission concentration (MTEC) approach. The MTEC is 
calculated as described in Sec.  63.1207(m)(2) except that, in this 
case, it is calculated for the hazardous waste feed(s) only.
    Although we believe that the preamble description of this approach 
is clear, the regulatory language, promulgated in Sec. Sec.  
63.1220(a)(2) and (b)(2), is not.\53\ Our intent was to require all 
affected cement kilns to comply with Sec.  63.1220(a)(2)(i). In 
addition, the source has the option of complying with either Sec.  
63.1220(a)(2)(ii) or (a)(2)(iii). However, the current language could 
be misinterpreted to allow the source to comply only with Sec.  
63.1220(a)(2)(iii).

[[Page 52642]]

Today, we are proposing to amend Sec.  63.1220(a)(2) to more clearly 
reflect our original intent. Conforming changes to the mercury 
monitoring requirements of Sec.  63.1209(l)(1)(iii) and (iv) are also 
proposed.
---------------------------------------------------------------------------

    \53\ For brevity, the remaining regulatory citations refer only 
to the standards for existing cement kilns. However, the same 
changes are proposed for both existing and new kilns.
---------------------------------------------------------------------------

L. Facilities Operating Under RCRA Interim Status

    In response to the proposed rule (69 FR at 21198), one commenter 
expressed concern that sources operating under Resource Conservation 
and Recovery Act (RCRA) interim status would have to obtain approval of 
the RCRA implementing authority before proceeding with facility 
modifications required to meet the MACT standards. The commenter noted 
that delays in gaining that approval would adversely affect a source's 
ability to comply with the MACT standards on time. We responded to this 
issue in our response to comments document.\54\ However, we did not 
address it in either the preamble or the final rule itself. 
Consequently, this appears to be an ongoing source of confusion among 
affected sources, as well as some regulatory agencies. In order to 
promote consistent interpretation of the RCRA interim status 
requirements across all jurisdictions, the discussion that follows 
reiterates EPA's long-standing position previously set forth in the 
comment response document. States are strongly encouraged to adhere to 
this interpretation in order to facilitate timely compliance with the 
HWC MACT replacement standards.
---------------------------------------------------------------------------

    \54\ USEPA, ``Response to Comments on April 20, 2004 HWC MACT 
Proposed Rule, Volume IV: Permitting,'' September 2005, Pages 16-17.
---------------------------------------------------------------------------

    At issue here is the interpretation of Sec.  270.72(a)(3), that 
requires sources operating under interim status to obtain approval from 
the regulatory authority for ``Changes in the processes for the 
treatment, storage, or disposal of hazardous waste or addition of 
processes * * *'' The term ``process'' refers to the general category 
of waste treatment, storage, or disposal (e.g., incinerator, cement 
kiln, boiler, etc.) as indicated on the Part A permit form (EPA Form 
8700-23). It does not include air pollution control devices, monitoring 
equipment, or process controls, none of which are identified on the 
Part A form. Consequently, changes to those monitoring and control 
systems do not require approval under Sec.  270.72(a)(3). Neither would 
a change in operating conditions (e.g., an increase in the combustion 
temperature) be subject to Sec.  272.72(a)(3) because operating 
conditions are also not included in the Part A permit form.
    We note that sources subject to the boiler and industrial furnace 
(BIF) requirements (40 CFR part 266, subpart H) under RCRA would be 
required to submit revised certifications of compliance when making any 
changes that could affect emissions or operating parameter limits. 
However, those changes do not require prior approval of the regulatory 
authority so they should not impede your compliance with the HWC MACT 
standards.

VI. Revised Time Lines

    The time line labeled as Figure 1 published in the final rule at 70 
FR at 59524, depicts an incorrect ``effective'' date for the Phase 1 
Replacement Standards and Phase 2 Standards final rule. As a result, 
all subsequent dates on the time line are also incorrect. The time line 
labeled as Figure 2 published in the final rule at 70 FR at 59525 
incorrectly includes the rule's effective date, as well as subsequent 
dates based on the effective date. Today's notice revises both time 
lines to reflect the correct dates or time frames associated with the 
compliance activities for both Phase 1 and Phase 2 sources. In addition 
to revising the dates, we felt it would be helpful to include the 
following remarks for both Figures 1 and 2.
    With respect to figure 1, the time line is now broken into three 
sections to reflect the separate requirements (i.e., different time 
frames) negotiated for Phase 1 sources for the Replacement Standards. 
The first section of the time line, beginning with the promulgation 
date, provides compliance activities and dates applicable to both Phase 
1 and Phase 2 sources. The second and third portions of the time line 
represent Phase 1 and Phase 2 sources individually, beginning with the 
first compliance activity that specifies a different deadline; that is, 
the comprehensive performance test (CPT) plan and continuous monitoring 
system (CMS) performance evaluation test plan due date.
    Note that the dates on the time line generally do not apply to 
sources that elect to comply with the final standards early, as well as 
to sources that have received site-specific compliance date or 
performance test date extensions. Also, as a result of expanding the 
time line into three sections from the previous two, we have removed 
the note at the bottom of the page, identified by an asterisk that 
discussed Title V requirements, to provide better visual clarity. 
Rather, we have chosen to reiterate it here in this notice. Therefore, 
for the activity identified as Include NOC in Title V Permit, we note 
that because of the variability of the Title V program requirements, 
most Title V permit actions (application due dates, revisions, 
reopenings, etc.) are not included in this time line. Please refer to 
the particular source's current Title V permit status, Title V 
regulations, and individual permitting authority's requirements.
    Finally, the compliance activity dates that are tied to when 
sources commence their performance test are identified with an 
asterisk. We characterize these dates as ``no later than dates.'' This 
assumes that the source commences testing on the last allowable day. 
All compliance activities marked with an asterisk would therefore shift 
back by the number of days the source commences testing prior to the 
last allowable day. For example, if a Phase 2 source commences testing 
on April 4, 2009 (versus the 14th, which is the last allowable day 
without an extension), then it must submit its CPT plan and CMS 
performance evaluation test plan on April 4, 2008. Also, that source 
must complete its CPT by June 4, 2009 and submit its notification of 
compliance no later than September 4, 2009.
    In regard to Figure 2, we have removed the dates from the time 
line, since they would not be representative of a new unit's compliance 
deadlines. A new unit's compliance activity deadlines are based on when 
it begins operations, which is the unit's compliance date and the date 
it must place a Documentation of Compliance in the operating record. 
Thus, the effective date of the rule is not applicable to new units and 
consequently, the Notice of Intent to Comply (NIC) provisions in 
Sec. Sec.  63.1210(b)(3) and (c)(1) that specify a deadline based on 
the effective date of the rule, also would not apply. Since we have 
always intended that new units follow the same NIC procedures as 
existing units, we have revised Sec. Sec.  63.1210(b)(3) and (c)(1) to 
also include the period of time between the NIC activities so that they 
correctly apply to both existing and new units. (See Section VII.C 
(Clarifications to the NIC Provisions for New Units) below for 
additional discussion.) The time line now reflects the period of time 
that elapses between public review of the draft NIC and CPT plan, the 
NIC public meeting, and the final NIC submission deadline. Aside from 
the corrections

[[Page 52643]]

made to this time line, we would like to remind readers that the 
preamble to the final rule contains a detailed discussion of the 
compliance activities listed on Figure 2. See 70 FR at 59522-59523.
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[[Page 52645]]

VII. Technical Corrections and Other Clarification

    We identified minor drafting errors and inadvertent omissions after 
promulgation of the HWC NESHAP. In this section we are providing 
advance notice of technical corrections that we plan to promulgate when 
we take final action on this proposed rule. In addition, we provide 
clarification of the applicability of Title V permit requirements to 
Phase 2 area sources.

A. What Typographical Errors Would We Correct?

    We would revise Sec.  63.1206(a)(2)(ii)(A) to correct the cut-off 
date after which a new or reconstructed source is subject to the new 
source emission standards. Currently, this paragraph incorrectly 
specifies October 12, 2005, which is the date the final rule was 
published, instead of April 20, 2004, which is the date the proposed 
rule was published. See proposed revision to Sec.  
63.1206(a)(2)(ii)(A).
    We also would correct the paragraph heading to Sec.  63.1206(a)(2) 
that currently refers to ``hydrogen chloride production furnaces'' 
instead of ``hydrochloric acid production furnaces.'' See proposed 
revision to Sec.  63.1206(a)(2). In addition, we would correct a 
provision that inadvertently uses incorrect terminology when referring 
to emissions of ``hydrogen chloride and chlorine gas.'' See proposed 
revision Sec.  63.1206(b)(16).
    We also would revise Sec.  63.1210(b) to clarify that the public 
meeting and notice requirements of the notice of intent to comply (NIC) 
provisions under paragraph (c) of this section do not apply to sources 
that have already submitted their NIC. We would also revise Sec.  
63.1210(b) to make clear that the NIC certification requirements under 
Sec.  63.1212(a) likewise do not apply to sources that have already 
submitted their NIC. See proposed revision to Sec.  63.1210(b).
    We also would correct the formula under Sec.  63.1215(b)(2) that is 
used to calculate the annual average toxicity-weighted HCl-equivalent 
emission rate for each hazardous waste combustor under the health-based 
compliance alternatives for total chlorine. The formula uses 
incorrectly the term ERtw instead of ERLTtw for 
the annual average HCl toxicity-weighted emission rate considering 
long-term exposures. See proposed revision to Sec.  63.1215(b)(2).
    We also would correct several other typographical errors in Sec.  
63.1215. First, paragraph (b)(6)(ii)(C) would be revised by replacing 
the word ``the se'' with ``these'' and the term ``Method 26/26a'' with 
``Method 26/26A.'' Additionally, paragraph (f)(5)(ii)(A) would be 
revised by replacing the word ``you'' with ``your.'' Finally, we would 
revise paragraphs (a)(2) and (b)(3) so that the term ``aREL'' (acute 
reference exposure level) is used consistently throughout Sec.  
63.1215. See proposed revisions to Sec. Sec.  63.1215(a)(2), (b)(3), 
(b)(6)(ii)(C) and (f)(5)(ii)(A).
    We also would revise the total chlorine standards for existing and 
new liquid fuel boilers that burn hazardous waste with an as-fired 
heating value of 10,000 Btu/lb or greater by expressing the emission 
standard with two significant figures. Currently, the total chlorine 
standards under Sec. Sec.  63.1217(a)(6)(ii) and (b)(6)(ii) are 
expressed with three significant figures. This is inconsistent with how 
emission standards are expressed in the HWC NESHAP (see Sec.  
63.1217(d) and 64 FR at 52848). Therefore, we would revise the total 
chlorine standard from 5.08E-02 to 5.1E-02 lb combined emissions of 
hydrogen chloride and chlorine gas attributable to the hazardous waste 
per million Btu heat input from the hazardous waste. See proposed 
revisions to Sec.  63.1217(a)(6)(ii) and (b)(6)(ii).

B. What Citations Would We Correct?

    We would revise an incorrect citation in Sec.  63.1206(b)(14)(iv) 
that refers inadvertently to paragraphs (e)(2) and (e)(3) instead of 
(b)(14)(ii) and (iii) in Sec.  63.1206. See proposed revision to Sec.  
63.1206(b)(14)(iv).
    Paragraphs (g)(2)(i) and (ii) under Sec.  63.1209 refer 
inadvertently to paragraph (g)(2)(iv) instead of (g)(2)(v). We would 
revise these incorrect citations. See proposed revisions to Sec. Sec.  
63.1209(g)(2)(i) and (ii).
    We also would revise an incorrect citation in Sec.  
63.1209(n)(2)(vii) that refers inadvertently to paragraphs (l)(1)(i) 
through (iii) instead of (n)(2)(ii) through (vi). See proposed revision 
to Sec.  63.1209(n)(2)(vii).
    We also would revise an incorrect citation in Sec.  
63.1215(a)(1)(i). This paragraph refers inadvertently to paragraph 
(b)(4) instead of (b)(7) of Sec.  63.1215. See proposed revision to 
Sec.  63.1215(a)(1)(i).
    In the final rule, we amended Sec.  264.340(b) by adding a new 
paragraph (b)(5) stating that the particulate matter standard under 
Sec.  264.343(c) remains in effect for incinerators that elect to 
comply with the alternative to the particulate matter standards under 
Sec. Sec.  63.1206(b)(14) and 63.1219(e). However, the addition of 
paragraph (b)(5) included a requirement that was redundant to existing 
requirements under paragraph (b)(3) of that same section. We would 
remove this redundancy by combining the requirements of paragraphs 
(b)(3) and (b)(5) into a revised paragraph (b)(3). See proposed 
revision to Sec.  264.340(b).
    We also would revise an incorrect citation in Sec.  266.100(b)(3) 
that contains two subparagraphs designated as (b)(3)(ii). This revision 
would redesignate the second paragraph (b)(3)(ii) as (b)(3)(iii). See 
proposed revision to Sec.  266.100(b)(3).

C. Corrections to the NIC Provisions for New Units

    In the final rule, we established additional Notice of Intent to 
Comply (NIC) provisions for new units to ensure that the public would 
be provided opportunities to participate early in the regulatory 
development process. This included providing the public with combustor-
specific information equivalent to what would be required via the RCRA 
permitting process for hazardous waste combustors. Recall that we no 
longer require new units to develop trial burn plans and provide 
suggested conditions for the various phases of operation in their 
permit applications or permit modification requests. See 70 FR at 
59520. The NIC provisions for new units, located under Sec. Sec.  
63.1212(b) and (c), were developed with the above in mind.
    While revising the time line for new units (see Figure 2 shown 
above in Section VI (Revised Time Lines)) it became apparent that we 
overlooked the fact that the final rule's effective date has no bearing 
on new units. A new unit's compliance activity deadlines are based on 
when it begins operations, which is the unit's compliance date and the 
date it must place a Documentation of Compliance in the operating 
record. Therefore, the NIC deadlines are only based upon each 
individual NIC compliance activity. For example, the clock will begin 
when the new unit provides the draft NIC and draft CPT plan to the 
public for review. Once the draft NIC and draft CPT plan are made 
available for public review, the combined public meeting must occur 30 
days later, followed by the final NIC submission an additional 60 days 
later. Since the public meetings for the NIC and the RCRA pre-
application or modification request must occur simultaneously, we 
anticipate that the new unit will plan accordingly and work with its 
permitting authorities to determine the most suitable time to begin the 
NIC compliance process.
    Although the time line for new units has been corrected to remove 
the effective date and the dates listed for the NIC activities, the NIC 
regulatory

[[Page 52646]]

language in Sec.  63.1210(b)(3) and (c)(1) must be amended to also 
account for new units. While the additional NIC provisions for new 
units are located in Sec.  63.1212(b) and (c), they contain several 
references to the core NIC provisions in Sec.  63.1210(b) and (c). 
Obviously, we have always intended that new units follow the same NIC 
procedures as existing units, in additionto the supplemental 
requirements for new units. In developing the additional requirements 
under Sec.  63.1212, we inadvertently neglected to revise Sec.  
63.1210(b)(3) and (c)(1) to include a specific number of days between 
NIC compliance activities in addition to the effective date. Therefore, 
the NIC provisions under Sec. Sec.  63.1210(b)(3) and (c)(1) would be 
revised to correctly apply to both existing and new units.
    Lastly, upon review of the regulations at Sec.  63.1212, we have 
discovered that paragraph (b)(4) should have included references to 
Sec.  63.1210(c)(1) and (c)(2). As discussed above, it has always been 
our intent that new units follow the same NIC procedures as existing 
units. However, without the proper references in Sec.  63.1212(b)(4), 
the requirements of Sec.  63.1210(c)(1) and (c)(2) could be read to not 
apply to new units. Section 63.1212(b)(4) would be revised to clarify 
that the core NIC provisions continue to be applicable. Also, Sec.  
63.1212 (b)(1) would be revised to remove ``according to'' and ``per'' 
and add the words ``pursuant to'' so that it is consistent with other 
paragraphs in (b); and Sec.  63.1212(b)(3) would be revised to correct 
a typographical error.

D. Clarification of the Applicability of Title V Permit Requirements to 
Phase 2 Area Sources

    In the preamble to the final rule, we discuss the applicability of 
Title V permit requirements to Phase 2 area sources (see 70 FR at 
59523). For example, we note that in the 2004 proposal we stated that 
we were not making a positive area source finding for Phase 2 area 
sources as we have for Phase 1 area sources (69 FR at 21212 and 21325). 
Regardless of this, however, we explain that Phase 2 area sources are 
still subject to the requirement to obtain a Title V permit because 
they are subject to section 112 standards. See section 502(a) of the 
CAA and 40 CFR 70.3(b)(2) and 71.3(b)(2).
    On this same page in the final rule preamble, we further explain 
that, in accordance with 40 CFR 70.3(c) and 70.5(c)(3), a Title V 
permit application needs to include emissions information relative to 
all regulated air pollutants that are emitted from the subject units, 
not just the specific HAP pollutants regulated by the MACT standards. 
However, we then say, ``Although, the permit itself would contain 
standards only for the HAP subject to MACT standards (the section 
112(c)(6) HAP).'' Initially this phrase was part of a longer sentence 
in a draft version of the preamble and was inadvertently incorporated 
into the final preamble. While the intent of the sentence was to note 
that a source cannot be required to control more HAP than is regulated 
by the relevant MACT standards, this sentence is not needed given that 
Title V permits cannot modify applicable requirements to address 
additional HAP. Moreover, this phrase is confusing given that all 
applicable requirements that apply to the subject area source units, 
not just the relevant MACT standard requirements, are required to be 
included in the permits for these units. Lastly, this phrase is 
confusing because it was included at a point in the discussion where 
permit applications, not permits, were being discussed.
    Therefore, in this action, we reiterate that a Title V permit 
application needs to include emissions information relative to all 
regulated air pollutants that are emitted from the units subject to the 
MACT standards, not just the specific HAP pollutants regulated by the 
MACT standards. Additionally, all MACT standards that apply to the 
subject units (e.g., subpart EEE for hazardous waste burning boilers 
and subpart DDDDD for non-hazardous waste burning boilers, etc.), as 
well as all other applicable requirements that apply to these subject 
units, e.g., State Implementation Plan requirements, are required to be 
included in the Title V permits for Phase 2 area sources.

VIII. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review

    Under Executive Order (EO) 12866 (58 FR 51735, October 4, 1993), 
this action is a ``significant regulatory action.'' Pursuant to the 
terms of Executive Order 12866, it has been determined that today's 
proposed rule constitutes a ``significant regulatory action'' because 
this action raises novel legal or policy issues arising out of legal 
mandates, the President's priorities, or the principles set forth in 
the Executive Order. Accordingly, EPA submitted this action to the 
Office of Management and Budget (OMB) for review under EO 12866 and any 
changes made in response to OMB recommendations have been documented in 
the docket for this action.
    This proposed rule is not considered to be an economically 
significant action because the total social costs for this proposed 
rule are significantly below the $100 million threshold established for 
economically significant actions.

B. Paperwork Reduction Act

    This action does not impose an information collection burden under 
the provisions of the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. 
because there is no additional burden on the industry as a result of 
the proposed rule, and the ICR has not been revised.
    Burden means the total time, effort, or financial resources 
expended by persons to generate, maintain, retain, or disclose or 
provide information to or for a Federal agency. This includes the time 
needed to review instructions; develop, acquire, install, and utilize 
technology and systems for the purposes of collecting, validating, and 
verifying information, processing and maintaining information, and 
disclosing and providing information; adjust the existing ways to 
comply with any previously applicable instructions and requirements; 
train personnel to be able to respond to a collection of information; 
search data sources; complete and review the collection of information; 
and transmit or otherwise disclose the information.
    An agency may not conduct or sponsor, and a person is not required 
to respond to a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for EPA's 
regulations in 40 CFR are listed in 40 CFR part 9.

C. Regulatory Flexibility Act

    The Regulatory Flexibility Act (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 impact of today's proposed rule on 
small entities, a small entity is defined as: (1) A small business as 
defined by the Small Business Administrations' regulations at 13 CFR 
121.201; (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; and (3) a small organization that is 
any not-for-profit enterprise which is independently

[[Page 52647]]

owned and operated and is not dominant in the 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. EPA has 
determined that none of the small entities will experience a 
significant economic impact because the notice imposes no additional 
regulatory requirements on owners or operators of affected sources. 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.

D. Unfunded Mandates Reform Act of 1995

    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 
one 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.
    EPA has determined that today's notice of reconsideration does not 
contain a Federal mandate that may result in expenditures of $100 
million or more for State, local, or tribal governments, in the 
aggregate, or to the private sector in any one year. Although our best 
estimate of total social costs of the final rule was $22.6 million per 
year, today's notice does not add new requirements that would increase 
this cost. See 70 FR at 59532. Thus, today's proposed rule is not 
subject to sections 202 and 205 of the UMRA. EPA has also determined 
that the notice of reconsideration contains no regulatory requirements 
that might significantly or uniquely affect small governments because 
it contains no regulatory requirements that apply to such governments 
or impose obligations upon them. Thus, today's proposed rule is not 
subject to the requirements of section 203.

E. 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'' is 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.''
    Today's 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 not projected to result in economic impacts to privately 
owned hazardous waste combustion facilities. Marginal administrative 
burden impacts may occur at selected States and/or EPA regional offices 
if these entities experience increased administrative needs or 
information requests. Thus, Executive Order 13132 does not apply to 
this rule.

F. Executive Order 13175: Consultation and Coordination With Indian 
Tribal Governments

    Executive Order 13175, entitled ``Consultation and Coordination 
with Indian Tribal Governments'' (65 FR 67249, November 9, 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.'' This notice of 
reconsideration does not have tribal implications, as specified in 
Executive Order 13175. No affected facilities are owned or operated by 
Indian tribal governments. Thus, Executive Order 13175 does not apply 
to this notice of reconsideration.

G. 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 E.O. 
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.
    Today's proposed rule is not subject to E.O. 13045 because it is 
not economically significant as defined under point one of the Order, 
and because the Agency does not have reason to believe the 
environmental health or safety risks addressed by this action present a 
disproportionate risk to children.

H. Executive Order 13211: Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use

    This rule is not a ``significant energy action'' as defined in 
Executive Order 13211, ``Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use'' (66 Fed Reg 
28355 (May 22, 2001) because it is not likely to have a significant 
adverse effect on the supply, distribution, or use of energy. Further, 
we have concluded that this rule is not likely to have any adverse 
energy effects.

I. National Technology Transfer and Advancement Act

    As described in the October 2005 final rule, Section 12(d) of the 
National Technology Transfer and Advancement Act of 1995 (``NTTAA''), 
Public Law No. 104-113, 12(d) (15 U.S.C. 272 note) directs EPA to use 
voluntary consensus standards in its regulatory activities

[[Page 52648]]

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. During the development of 
the final rule, EPA searched for voluntary consensus standards that 
might be applicable. The search identified the following consensus 
standards that were considered practical alternatives to the specified 
EPA test methods: (1) American Society for Testing and Materials (ASTM) 
D6735-01, ``Standard Test Method for Measurement of Gaseous Chlorides 
and Fluorides from Mineral Calcining Exhaust Sources--Impinger 
Method,'' and (2) American Society of Mechanical Engineers (ASME) 
standard QHO-1-2004, ``Standard for the Qualification and Certification 
of Hazardous Waste Incineration Operators.'' Today's notice of 
reconsideration does not propose the use of any additional technical 
standards beyond those cited in the final rule. Therefore, EPA is not 
considering the use of any additional voluntary consensus standards for 
this notice.

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 266

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

    Dated: August 24, 2006.
Stephen L. Johnson,
Administrator.

    For the reasons set out in the preamble, title 40, chapter I of the 
Code of Federal Regulations is proposed to be 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 63.1203 is amended by adding paragraph (e) to read as 
follows:


Sec.  63.1203  What are the standards for hazardous waste incinerators 
that are effective until compliance with the standards under Sec.  
63.1219?

* * * * *
    (e) The provisions of this section no longer apply after any of the 
following dates, whichever occurs first:
    (1) The date that your source begins to comply with Sec.  63.1219 
by placing a Documentation of Compliance in the operating record 
pursuant to Sec.  63.1211(c);
    (2) The date that your source begins to comply with Sec.  63.1219 
by submitting a Notification of Compliance pursuant to Sec.  
63.1210(b); or
    (3) The date for your source to comply with Sec.  63.1219 pursuant 
to Sec.  63.1206 and any extensions granted thereunder.
    3. Section 63.1204 is amended by adding paragraph (i) to read as 
follows:


Sec.  63.1204  What are the standards for hazardous waste burning 
cement kilns that are effective until compliance with the standards 
under Sec.  63.1220?

* * * * *
    (i) The provisions of this section no longer apply after any of the 
following dates, whichever occurs first:
    (1) The date that your source begins to comply with Sec.  63.1220 
by placing a Documentation of Compliance in the operating record 
pursuant to Sec.  63.1211(c);
    (2) The date that your source begins to comply with Sec.  63.1220 
by submitting a Notification of Compliance pursuant to Sec.  
63.1210(b); or
    (3) The date for your source to comply with Sec.  63.1220 pursuant 
to Sec.  63.1206 and any extensions granted thereunder.
    4. Section 63.1205 is amended by adding paragraph (e) to read as 
follows:


Sec.  63.1205  What are the standards for hazardous waste burning 
lightweight aggregate kilns that are effective until compliance with 
the standards under Sec.  63.1221?

* * * * *
    (e) The provisions of this section no longer apply after any of the 
following dates, whichever occurs first:
    (1) The date that your source begins to comply with Sec.  63.1221 
by placing a Documentation of Compliance in the operating record 
pursuant to Sec.  63.1211(c);
    (2) The date that your source begins to comply with Sec.  63.1221 
by submitting a Notification of Compliance pursuant to Sec.  
63.1210(b); or
    (3) The date for your source to comply with Sec.  63.1221 pursuant 
to Sec.  63.1206 and any extensions granted thereunder.
    5. Section 63.1206 is amended as follows:
    a. By revising paragraph (a)(2) paragraph heading and the first 
sentence of paragraph (a)(2)(ii)(A).
    b. By revising paragraphs (b)(14)(iv) and (b)(16) introductory 
text.
    c. By revising paragraph (c)(9) introductory text.


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

    (a) * * *
    (2) Compliance date for solid fuel boilers, liquid fuel boilers, 
and hydrochloric acid production furnaces that burn hazardous waste for 
standards under Sec. Sec.  63.1216, 63.1217, and 63.1218. * * *
* * * * *
    (ii) * * * (A) If you commenced construction or reconstruction of 
your hazardous waste combustor after April 20, 2004, you must comply 
with the new source emission standards of this subpart by the later of 
October 12, 2005, or the date the source starts operations, except as 
provided by paragraph (a)(2)(ii)(B) of this section. * * *
* * * * *
    (b) * * *
    (14) * * *
    (iv) Operating limits. Semivolatile and low volatile metal 
operating parameter limits must be established to ensure compliance 
with the alternative emission limitations described in paragraphs 
(b)(14)(ii) and (iii) of this section pursuant to Sec.  63.1209(n), 
except that semivolatile metal feedrate limits apply to lead, cadmium, 
and selenium, combined, and low volatile metal feedrate limits apply to 
arsenic, beryllium, chromium, antimony, cobalt, manganese, and nickel, 
combined.
* * * * *
    (16) Compliance with subcategory standards for liquid fuel boilers. 
You must comply with the mercury, semivolatile metals, low volatile 
metals, and hydrogen chloride and chlorine gas standards for liquid 
fuel boilers under Sec.  63.1217 as follows:
    (c) * * *
    (9) Particulate matter detection system requirements. If your 
combustor is equipped with an electrostatic precipitator or ionizing 
wet scrubber and you elect not to establish under Sec.  
63.1209(m)(1)(iv) site-specific control

[[Page 52649]]

device operating parameter limits that are linked to the automatic 
waste feed cutoff system under paragraph (c)(3) of this section, or 
your combustor is equipped with a fabric filter and you elect to use a 
particulate matter detection system pursuant to paragraph (c)(8)(i)(B) 
of this section, you must continuously operate a particulate matter 
detection system that meets the specifications and requirements of 
paragraph (c)(9)(i) through (iii) of this section and you must comply 
with the corrective measures and notification requirements of 
paragraphs (c)(9)(iv) through (v) of this section.
* * * * *
    6. Section 63.1207 is amended as follows:
    a. By adding paragraph (b)(3)(vi).
    b. By revising paragraphs (d)(1), (d)(2), and (d)(4).
    c. By revising the first sentence of paragraphs (g)(2)(i) and 
(g)(2)(ii).
    d. By revising paragraph (m).


Sec.  63.1207  What are the performance testing requirements?

* * * * *
    (b) * * *
    (3) * * *
    (vi) Sources that are required to perform the one-time dioxin/furan 
test pursuant to paragraph (b)(3) of this section are not required to 
perform confirmatory performance tests.
* * * * *
    (d) * * *
    (1) Comprehensive performance testing. Except as otherwise 
specified in paragraph (d)(4) of this section, you must commence 
testing no later than 61 months after the date of commencing the 
previous comprehensive performance test used to show compliance with 
Sec. Sec.  63.1216, 63.1217, 63.1218, 63.1219, 63.1220, or 63.1221. If 
you submit data in lieu of the initial performance test, you must 
commence the subsequent comprehensive performance test within 61 months 
of commencing the test used to provide the data in lieu of the initial 
performance test.
    (2) Confirmatory performance testing. Except as otherwise specified 
in paragraph (d)(4) of this section, you must commence confirmatory 
performance testing no later than 31 months after the date of 
commencing the previous comprehensive performance test used to show 
compliance with Sec. Sec.  63.1216, 63.1217, 63.1218, 63.1219, 63.1220, 
or 63.1221. If you submit data in lieu of the initial performance test, 
you must commence the initial confirmatory performance test within 31 
months of the date six months after the compliance date. To ensure that 
the confirmatory test is conducted approximately midway between 
comprehensive performance tests, the Administrator will not approve a 
test plan that schedules testing within 18 months of commencing the 
previous comprehensive performance test.
* * * * *
    (4) Applicable testing requirements under the interim standards. 
(i) Waiver of periodic comprehensive performance tests. Except as 
provided by paragraph (c)(2) of this section, you must conduct only an 
initial comprehensive performance test under the interim standards 
(i.e., the standards published in the Federal Register on February 13, 
2002); all subsequent comprehensive performance testing requirements 
are waived under the interim standards. The provisions in the 
introductory text to paragraph (d) and in paragraph (d)(1) of this 
section apply only to tests used to demonstrate compliance with the 
permanent replacement standards promulgated on or after October 12, 
2005.
    (ii) Waiver of confirmatory performance tests. You are not required 
to conduct a confirmatory test under the interim standards (i.e., the 
standards published in the Federal Register on February 13, 2002). The 
confirmatory testing requirements in the introductory text to paragraph 
(d) and in paragraph (d)(2) of this section apply only after you have 
demonstrated compliance with the permanent replacement standards 
promulgated on or after October 12, 2005.
* * * * *
    (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)(v) of this section. * * *
    (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)(v) of this section. * * *
* * * * *
    (m) Waiver of performance test. You are not required to conduct 
performance tests to document compliance with the mercury, semivolatile 
metals, low volatile metals, or hydrogen chloride/chlorine gas emission 
standards under the conditions specified in paragraphs (m)(1) or (m)(2) 
of this section. The waiver provisions of this paragraph apply in 
addition to the provisions of Sec.  63.7(h).
    (1) Emission standards based on exhaust gas flow rate. (i) You are 
deemed to be in compliance with an emission standard based on the 
volumetric flow rate of exhaust gas (i.e. [mu]g/dscm or ppmv) if the 
twelve-hour rolling average maximum theoretical emission concentration 
(MTEC) determined as specified below does not exceed the emission 
standard:
    (A) Determine the feedrate of mercury, semivolatile metals, low 
volatile metals, or total chlorine and chloride from all feedstreams;
    (B) Determine the stack gas flowrate; and
    (C) Calculate a MTEC for each standard assuming all mercury, 
semivolatile metals, low volatile metals, or total chlorine (organic 
and inorganic) from all feedstreams is emitted;
    (ii) To document compliance with this provision, you must:
    (A) Monitor and record the feedrate of mercury, semivolatile 
metals, low volatile metals, and total chlorine and chloride from all 
feedstreams according to Sec.  63.1209(c);
    (B) Monitor with a CMS and record in the operating record the gas 
flowrate (either directly or by monitoring a surrogate parameter that 
you have correlated to gas flowrate);
    (C) Continuously calculate and record in the operating record the 
MTEC under the procedures of paragraph (m)(1)(i) of this section; and
    (D) Interlock the MTEC calculated in paragraph (m)(1)(i)(C) of this 
section to the AWFCO system to stop hazardous waste burning when the 
MTEC exceeds the emission standard.
    (iii) In lieu of the requirement in paragraphs (m)(1)(ii)(C) and 
(D) of this section, you may:
    (A) Identify in the Notification of Compliance a minimum gas 
flowrate limit and a maximum feedrate limit of mercury, semivolatile 
metals, low volatile metals, and/or total chlorine and chloride from 
all feedstreams that ensures the MTEC as calculated in paragraph 
(m)(1)(i)(C) of this section is below the applicable emission standard; 
and
    (B) Interlock the minimum gas flowrate limit and maximum feedrate 
limit of paragraph (m)(1)(iii)(A) of this section to the AWFCO system 
to stop hazardous waste burning when the gas flowrate or mercury, 
semivolatile metals, low volatile metals, and/or total chlorine and 
chloride feedrate exceeds the limits of paragraph (m)(1)(iii)(A) of 
this section.
    (2) Emission standards based on hazardous waste thermal 
concentration.

[[Page 52650]]

(i) You are deemed to be in compliance with an emission standard 
specified on a hazardous waste thermal concentration basis (i.e., 
pounds emitted per million Btu of heat input) if the HAP thermal 
concentration in the waste feed does not exceed the allowable HAP 
thermal concentration emission rate.
    (ii) To document compliance with this provision, you must:
    (A) Monitor and record the feedrate of mercury, semivolatile 
metals, low volatile metals, and total chlorine and chloride from all 
hazardous waste feedstreams in accordance with Sec.  63.1209(c);
    (B) Determine and record the higher heating value of each hazardous 
waste feed;
    (C) Continuously calculate and record the thermal feed rate of all 
hazardous waste feedstreams by summing the products of each hazardous 
waste feed rate multiplied by the higher heating value of that 
hazardous waste;
    (D) Continuously calculate and record the total HAP thermal feed 
concentration for each constituent by dividing the HAP feedrate 
determined in paragraph (m)(2)(ii)(A) of this section by the thermal 
feed rate determined in paragraph (m)(2)(ii)(C) of this section for all 
hazardous waste feedstreams;
    (E) Interlock the HAP thermal feed concentration for each 
constituent with the AWFCO to stop hazardous waste feed when the 
thermal feed concentration exceeds the applicable thermal emission 
standard.
    (3) When you determine the feedrate of mercury, semivolatile 
metals, low volatile metals, or total chlorine and chloride for 
purposes of this provision, except as provided by paragraph (m)(4) of 
this section, you must assume that the analyte is present at the full 
detection limit when the feedstream analysis determines that the 
analyte is not detected is the feedstream.
    (4) Owners and operators of hazardous waste burning cement kilns 
and lightweight aggregate kilns may assume that mercury is present in 
raw material at half the detection limit when the raw material 
feedstream analysis determines that mercury is not detected.
    (5) You must state in the site-specific test plan that you submit 
for review and approval under paragraph (e) of this section that you 
intend to comply with the provisions of this paragraph. You must 
include in the test plan documentation that any surrogate that is 
proposed for gas flowrate adequately correlates with the gas flowrate.
    7. Section 63.1209 is amended as follows:
    a. By revising paragraphs (l)(1)(iii)(B), (l)(1)(iii)(C) 
introductory text, (l)(1)(iii)(D)(1), and (l)(1)(iii)(D)(2).
    b. By revising paragraphs (n)(2)(iii)(A), (n)(2)(v)(A)(2)(iv), 
(n)(2)(v)(B)(1)(i), (n)(2)(v)(B)(1)(ii), (n)(2)(v)(B)(2), and the first 
sentence of paragraph (n)(2)(vii) introductory text.
    c. By revising paragraph (o)(1)(ii)(A)(3).


Sec.  63.1209  What are the monitoring requirements?

* * * * *
    (l) * * *
    (1) * * *
    (iii) * * *
    (B) When complying with the emission standards under Sec. Sec.  
63.1204 and 63.1220(a)(2)(ii)(A) and (b)(2)(ii)(A), you must establish 
a 12-hour rolling average limit for the feedrate of mercury in all 
feedstreams as the average of the test run averages;
    (C) Except as provided by paragraph (l)(1)(iii)(D) of this section, 
when complying with the hazardous waste maximum theoretical emission 
concentration (MTEC) under Sec.  63.1220(a)(2)(ii)(B) and 
(b)(2)(ii)(B), you must:
* * * * *
    (D) * * *
    (1) Identify in the Notification of Compliance a minimum gas 
flowrate limit and a maximum feedrate limit of mercury from all 
hazardous waste feedstreams that ensures the MTEC calculated in 
paragraph (l)(1)(iii)(C)(4) of this section is below the operating 
requirement under paragraphs Sec. Sec.  63.1220(a)(2)(ii)(B) and 
(b)(2)(ii)(B); and
    (2) Initiate an automatic waste feed cutoff that immediately and 
automatically cuts off the hazardous waste feed when either the gas 
flowrate or mercury feedrate exceeds the limits identified in paragraph 
(l)(1)(iii)(D)(1) of this section.
* * * * *
    (n) * * *
    (2) * * *
    (iii) * * * (A) When complying with the emission standards under 
Sec.  63.1220(a)(3)(i), (a)(4)(i), (b)(3)(i), and (b)(4)(i), you must 
establish 12-hour rolling average feedrate limits for semivolatile and 
low volatile metals as the thermal concentration of semivolatile metals 
or low volatile metals in all hazardous waste feedstreams. You must 
calculate hazardous waste thermal concentrations for semivolatile 
metals and low volatile metals for each run as the total mass feedrate 
of semivolatile metals or low volatile metals for all hazardous waste 
feedstreams divided by the total heat input rate for all hazardous 
waste feedstreams. The 12-hour rolling average feedrate limits for 
semivolatile metals and low volatile metals are the average of the test 
run averages, calculated on a thermal concentration basis, for all 
hazardous waste feeds.
* * * * *
    (v) * * *
    (A) * * *
    (2) * * *
    (iv) If you select an averaging period for the feedrate limit that 
is greater than a 12-hour rolling average, you must calculate the 
initial rolling average as though you had selected a 12-hour rolling 
average, as provided by paragraph (b)(5)(i) of this section. 
Thereafter, you must calculate rolling averages using either one-minute 
or one-hour updates. Hourly updates shall be calculated using the 
average of the one-minute average data for the preceding hour. For the 
period beginning with initial operation under this standard until the 
source has operated for the full averaging period that you select, the 
average feedrate shall be based only on actual operation under this 
standard.
* * * * *
    (B) * * *
    (1) * * *
    (i) The 12-hour rolling average feedrate limit is a hazardous waste 
thermal concentration limit expressed as pounds of chromium in all 
hazardous waste feedstreams per million Btu of hazardous waste fed to 
the boiler. You must establish the 12-hour rolling average feedrate 
limit as the average of the test run averages.
    (ii) You must comply with the hazardous waste chromium thermal 
concentration limit by determining the feedrate of chromium in all 
hazardous waste feedstreams (lb/hr) and the hazardous waste thermal 
feedrate (MMBtu/hr) at least once each minute as [hazardous waste 
chromium feedrate (lb/hr)/hazardous waste thermal feedrate (MMBtu/hr)].
    (2) Boilers that feed hazardous waste with a heating value less 
than 10,000 Btu/lb. You must establish a 12-hour rolling average limit 
for the total feedrate (lb/hr) of chromium in all feedstreams as the 
average of the test run averages.
* * * * *
    (vii) Extrapolation of feedrate levels. In lieu of establishing 
feedrate limits as specified in paragraphs (n)(2)(ii) through (vi) of 
this section, you may request as part of the performance test plan 
under Sec. Sec.  63.7(b) and (c) and Sec. Sec.  63.1207(e) and (f) to 
use the semivolatile metal and low volatile metal feedrates and 
associated emission

[[Page 52651]]

rates during the comprehensive performance test to extrapolate to 
higher allowable feedrate limits and emission rates. * * *
* * * * *
    (o) * * *
    (1) * * *
    (ii) * * *
    (A) * * *
    (3) You must comply with the feedrate limit by determining the mass 
feedrate of hazardous waste feedstreams (lb/hr) at least once a minute 
and by knowing the chlorine content (organic and inorganic, lb of 
chlorine/lb of hazardous waste) and heating value (Btu/lb) of hazardous 
waste feedstreams at all times to calculate a 1-minute average feedrate 
measurement as [hazardous waste chlorine content (lb of chlorine/lb of 
hazardous waste feed)/hazardous waste heating value (Btu/lb of 
hazardous waste)]. You must update the rolling average feedrate each 
hour with this 60-minute average feedrate measurement.
* * * * *
    8. Section 63.1210 is amended by revising paragraphs (b) 
introductory text, (b)(3), and (c)(1) to read as follows:


Sec.  63.1210  What are the notification requirements?

* * * * *
    (b) Notification of intent to comply (NIC). These procedures apply 
to sources that have not previously complied with the requirements of 
paragraphs (b) and (c) of this section, and to sources that previously 
complied with the NIC requirements of Sec. Sec.  63.1210 and 
63.1212(a), which were in effect prior to October 11, 2000, that must 
make a technology change requiring a Class 1 permit modification to 
meet the standards of Sec. Sec.  63.1219, 63.1220, and 63.1221.
* * * * *
    (3) You must submit the final NIC to the Administrator no later 
than one year following the effective date of the emission standards of 
this subpart or 60 days following the informal public meeting.
    (c) * * * (1) Prior to the submission of the NIC to the permitting 
agency, and no later than 10 months after the effective date of the 
emission standards of this subpart or 30 days following notice of the 
informal public meeting, you must hold at least one informal meeting 
with the public to discuss the anticipated activities described in the 
draft NIC for achieving compliance with the emission standards of this 
subpart. You must post a sign-in sheet or otherwise provide a voluntary 
opportunity for attendees to provide their names and addresses.
* * * * *
    9. Section 63.1212 is amended by revising paragraphs (b)(1), 
(b)(3), and (b)(4) to read as follows:


Sec.  63.1212  What are the other requirements pertaining to the NIC?

* * * * *
    (b) * * *
    (1) Prepare a draft NIC pursuant to Sec.  63.1210(b) and make it 
available to the public upon issuance of the notice of public meeting 
pursuant to Sec.  63.1210(c)(3);
* * * * *
    (3) Provide notice to the public of a pre-application meeting 
pursuant to Sec.  124.30 of this chapter or notice to the public of a 
permit modification request pursuant to Sec.  270.42 of this chapter; 
and
    (4) Hold an informal public meeting, pursuant to Sec. Sec.  
63.1210(c)(1) and (c)(2), 30 days following notice of the NIC public 
meeting and notice of the pre-application meeting or notice of the 
permit modification request to discuss anticipated activities described 
in the draft NIC and pre-application or permit modification request for 
achieving compliance with the emission standards of this subpart.
* * * * *
    10. Section 63.1215 is amended as follows:
    a. By revising paragraph (a)(1)(i).
    b. By revising the definitions of ``1-Hour Average HCl-Equivalent 
Emission Rate'' and ``1-Hour Average HCl-Equivalent Emission Rate 
Limit'' in paragraph (a)(2).
    c. By revising paragraphs (b)(2), (b)(3), and (b)(6)(ii)(C).
    d. By revising paragraphs (e)(2)(i)(B), (e)(2)(i)(C), and 
(e)(2)(i)(D).
    e. By adding paragraph (e)(3).
    f. By revising paragraph (f)(5)(ii)(A).
    g. By revising paragraph (h)(2)(i).


Sec.  63.1215  What are health-based compliance alternatives for total 
chlorine?

    (a) * * *
    (1)
    (i) Identify a total chlorine emission concentration (ppmv) 
expressed as chloride (Cl(-)) equivalent for each on-site hazardous 
waste combustor. You may select total chlorine emission concentrations 
as you choose to demonstrate eligibility for the risk-based limits 
under this section, except as provided by paragraph (b)(7) of this 
section;
* * * * *
    (2) * * *
    1-Hour Average HCl-Equivalent Emission Rate means the HCl-
equivalent emission rate (lb/hr) determined by equating the toxicity of 
chlorine to HCl using aRELs as the health risk metric for acute 
exposure.
    1-Hour Average HCl-Equivalent Emission Rate Limit means the HCl-
equivalent emission rate (lb/hr) determined by equating the toxicity of 
chlorine to HCl using aRELs as the health risk metric for acute 
exposure and which ensures that maximum 1-hour average ambient 
concentrations of HCl-equivalents do not exceed a Hazard Index of 1.0, 
rounded to the nearest tenths decimal place (0.1), at an off-site 
receptor location.
* * * * *
    (b) * * *
    (2) Annual average rates. You must calculate annual average 
toxicity-weighted HCl-equivalent emission rates for each combustor as 
follows:

ERLTtw = ERHCl + ERCl2 x 
(RfCHCl/RfCCl2)

Where:

ERLTtw is the annual average HCl toxicity-weighted emission 
rate (HCl-equivalent emission rate) considering long-term exposures, 
lb/hr
ERHCl is the emission rate of HCl in lbs/hr
ERCl2 is the emission rate of chlorine in lbs/hr
RfCHCl is the reference concentration of HCl
RfCCl2 is the reference concentration of chlorine
    (3) 1-hour average rates. You must calculate 1-hour average 
toxicity-weighted HCl-equivalent emission rates for each combustor as 
follows:
ERSTtw = ERHCl + ERCl2 x 
(aRELHCl/aRELCl2)

Where:

ERSTtw is the 1-hour average HCl-toxicity-weighted emission 
rate (HCl-equivalent emission rate) considering 1-hour (short-term) 
exposures, lb/hr
ERHCl is the emission rate of HCl in lbs/hr
ERCl2 is the emission rate of chlorine in lbs/hr
aRELHCl is the aREL for HCl
aRELCl2 is the aREL for chlorine
* * * * *
    (6) * * *
    (ii) * * *
    (C) You must calculate the 1-hour average HCl-equivalent emission 
rate using these HCl and Cl2 emission rates and the equation 
in paragraph (b)(3) of this section.
* * * * *
    (e) * * *
    (2) * * *
    (i) * * *

[[Page 52652]]

    (B) Your permitting authority should notify you of approval or 
intent to disapprove your eligibility demonstration within 6 months 
after receipt of the original demonstration, and within 3 months after 
receipt of any supplemental information that you submit. A notice of 
intent to disapprove your eligibility demonstration, whether before or 
after the compliance date, will identify incomplete or inaccurate 
information or noncompliance with prescribed procedures and specify how 
much time you will have to submit additional information or to achieve 
the MACT standards for total chlorine under Sec. Sec.  63.1216, 
63.1217, 63.1219, 63.1220, and 63.1221. If your eligibility 
demonstration is disapproved, the permitting authority may extend the 
compliance date of the total chlorine standards up to one year to allow 
you to make changes to the design or operation of the combustor or 
related systems as quickly as practicable to enable you to achieve 
compliance with the MACT total chlorine standards.
    (C) If your permitting authority has not approved your eligibility 
demonstration by the compliance date, and has not issued a notice of 
intent to disapprove your demonstration, you may begin complying, on 
the compliance date, with the HCl-equivalent emission rate limits you 
present in your eligibility demonstration provided that you have made a 
good faith effort to provide complete and accurate information and to 
respond to any requests for additional information in a timely manner. 
If the permitting authority believes that you have not made a good 
faith effort to provide complete and accurate information or to respond 
to any requests for additional information, however, the authority may 
notify you in writing by the compliance date that you have not met the 
conditions for complying with the health-based compliance alternative 
without prior approval. Such notice will explain the basis for 
concluding that you have not made a good faith effort to comply with 
the health-based compliance alternative by the compliance date.
    (D) If your permitting authority issues a notice of intent to 
disapprove your eligibility demonstration after the compliance date, 
the authority will identify the basis for that notice and specify how 
much time you will have to submit additional information or to comply 
with the MACT standards for total chlorine under Sec. Sec.  63.1216, 
63.1217, 63.1219, 63.1220, and 63.1221. The permitting authority may 
extend the compliance date of the total chlorine standards up to one-
year to allow you to make changes to the design or operation of the 
combustor or related systems as quickly as practicable to enable you to 
achieve compliance with the MACT standards for total chlorine.
* * * * *
    (3) The operating requirements in the eligibility demonstration are 
applicable requirements for purposes of parts 70 and 71 of this chapter 
and will be incorporated in the title V permit.
    (f) * * *
    (5) * * *
    (ii) * * *
    (A) You must determine your chlorine emissions to be the higher of 
the value measured by Method 26/26A, or an equivalent method, or the 
value calculated by the difference between the combined hydrogen 
chloride and chlorine levels measured by Method 26/26A, or an 
equivalent method, and the hydrogen chloride measurement from EPA 
Method 320/321 or ASTM D 6735-01, or an equivalent method.
* * * * *
    (h) * * *
    (2) * * *
    (i) Proactive review. You must submit for review and approval with 
each comprehensive performance test plan either a certification that 
the information used in your eligibility demonstration has not changed 
in a manner that would decrease the annual average or 1-hour average 
HCl-equivalent emission rate limit, or a revised eligibility 
demonstration.
* * * * *
    11. Section 63.1216 is amended by revising paragraph (a)(7) to read 
as follows:


Sec.  63.1216  What are the standards for solid fuel boilers that burn 
hazardous waste?

    (a) * * *
    (7) For particulate matter, except for an area source as defined 
under Sec.  63.2 or as provided by paragraph (e) of this section, 
emissions in excess of 69 mg/dscm corrected to 7 percent oxygen.
* * * * *
    12. Section 63.1217 is amended by revising paragraphs (a)(6)(ii), 
(a)(7), and (b)(6)(ii) to read as follows:


Sec.  63.1217  What are the standards for liquid fuel boilers that burn 
hazardous waste?

    (a) * * *
    (6) * * *
    (ii) When you burn hazardous waste with an as-fired heating value 
of 10,000 Btu/lb or greater, emissions in excess of 5.1 x 10 
-\2\ lbs combined emissions of hydrogen chloride and 
chlorine gas attributable to the hazardous waste per million Btu heat 
input from the hazardous waste;
    (7) For particulate matter, except for an area source as defined 
under Sec.  63.2 or as provided by paragraph (e) of this section, 
emissions in excess of 79 mg/dscm corrected to 7 percent oxygen.
* * * * *
    (b) * * *
    (6) * * *
    (ii) When you burn hazardous waste with an as-fired heating value 
of 10,000 Btu/lb or greater, emissions in excess of 5.1 x 10 
-2 lbs combined emissions of hydrogen chloride and chlorine 
gas attributable to the hazardous waste per million Btu heat input from 
the hazardous waste;
* * * * *
    13. Section 63.1219 is amended by revising paragraphs (a)(7) and 
(b)(7) to read as follows:


Sec.  63.1219  What are the replacement standards for hazardous waste 
incinerators?

    (a) * * *
    (7) Except as provided by paragraph (e) of this section, 
particulate matter in excess of 30 mg/dscm corrected to 7 percent 
oxygen.
    (b) * * *
    (7) Except as provided by paragraph (e) of this section, 
particulate matter in excess of 3.5 mg/dscm corrected to 7 percent 
oxygen.
* * * * *
    14. Section 63.1220 is amended as follows:
    a. By revising paragraphs (a)(2)(ii) and (a)(7)(i).
    b. By revising paragraphs (b)(2)(ii) and (b)(7)(i).


Sec.  63.1220  What are the replacement standards for hazardous waste 
burning cement kilns?

    (a) * * *
    (2) * * *
    (ii) Either:
    (A) Emissions in excess of 120 [mu]g/dscm, corrected to 7 percent 
oxygen, or
    (B) A hazardous waste feed maximum theoretical emission 
concentration (MTEC) in excess of 120 [mu]g/dscm;
* * * * *
    (7) * * *
    (i) Emissions in excess of 65 mg/dscm corrected to 7 percent 
oxygen; and
* * * * *
    (b) * * *
    (2) * * *
    (ii) Either:
    (A) Emissions in excess of 120 [mu]g/dscm, corrected to 7 percent 
oxygen, or
    (B) A hazardous waste feed maximum theoretical emission 
concentration (MTEC) in excess of 120 [mu]g/dscm;
* * * * *
    (7) * * *

[[Page 52653]]

    (i) Emissions in excess of 5.3 mg/dscm corrected to 7 percent 
oxygen; and
* * * * *
    15. Section 63.1221 is amended by revising paragraphs (a)(7) and 
(b)(7) to read as follows:


Sec.  63.1221  What are the replacement standards for hazardous waste 
burning lightweight aggregate kilns?

    (a) * * *
    (7) Particulate matter emissions in excess of 57 mg/dscm corrected 
to 7 percent oxygen.
    (b) * * *
    (7) Particulate matter emissions in excess of 22 mg/dscm corrected 
to 7 percent oxygen.
* * * * *

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

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

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

    17. Section 264.340 is amended as follows:
    a. By revising the first sentence of paragraph (b)(1) and paragraph 
(b)(3).
    b. By removing paragraph (b)(5).


Sec.  264.340  Applicability.

* * * * *
    (b) * * * (1) Except as provided by paragraphs (b)(2) through 
(b)(4) of this section, the standards of this part do not apply to a 
new hazardous waste incineration unit that becomes subject to RCRA 
permit requirements after October 12, 2005; or no longer apply when an 
owner or operator of an existing hazardous waste incineration unit 
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 Sec. Sec.  63.1207(j) 
and 63.1210(d) of this chapter documenting compliance with the 
requirements of part 63, subpart EEE, of this chapter. * * *
* * * * *
    (3) The particulate matter standard of Sec.  264.343(c) remains in 
effect for incinerators that elect to comply with the alternative to 
the particulate matter standard under Sec. Sec.  63.1206(b)(14) and 
63.1219(e) of this chapter.
* * * * *

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

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

    Authority: 42 U.S.C. 1006, 2002(a), 3001-3009, 3014, 6905, 6906, 
6912, 6921, 6922, 6924-6927, 6934, and 6937.

    19. Section 266.100 is amended by redesignating the second 
paragraph (b)(3)(ii) as (b)(3)(iii).


Sec.  266.100  [Amended]

[FR Doc. 06-7251 Filed 9-5-06; 8:45 am]
BILLING CODE 6560-50-P