National Emission Standards for Hazardous Air Pollutants for Industrial, Commercial, and Institutional Boilers and Process Heaters: Reconsideration, 36907-36915 [05-12662]

Agencies

• ENVIRONMENTAL PROTECTION AGENCY

[Federal Register Volume 70, Number 122 (Monday, June 27, 2005)]
[Proposed Rules]
[Pages 36907-36915]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-12662]


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

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 63

[OAR-2002-0058; FRL-7928-7]
RIN 2060-AM97


National Emission Standards for Hazardous Air Pollutants for 
Industrial, Commercial, and Institutional Boilers and Process Heaters: 
Reconsideration

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule; notice of reconsideration of final rule; request 
for public comment.

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

SUMMARY: The EPA is requesting comment on certain aspects of our 
national emission standards for hazardous air pollutants (NESHAP) for 
industrial, commercial, and institutional boilers and process heaters, 
which EPA promulgated on September 13, 2004.
    After promulgation of the final regulations for boilers and process 
heaters, the Administrator received petitions for reconsideration of 
certain provisions in the final rule. In this document, the EPA is 
initiating the reconsideration of some of those provisions. We are 
requesting comment on certain provisions of the approach used to 
demonstrate eligibility for the health-based compliance alternatives, 
as outlined in appendix A of the final rule, and on the provisions 
establishing a health-based compliance alternative for total selected 
metals. We are not requesting comment on any other provisions of the 
final rule. We are not granting petitioners' request that we stay the 
effectiveness of the health-based compliance provisions of the final 
rule, pending this reconsideration action.

DATES: Comments. Comments must be received on or before August 11, 
2005.
    Public Hearing. If anyone contacts EPA requesting to speak at a 
public hearing by July 7, 2005, a public hearing will be held on July 
12, 2005. For further information on the public hearing and requests to 
speak, see the ADDRESSES section of this preamble.

ADDRESSES: Comments. Submit your comments, identified by Docket ID No. 
OAR-2002-0058 (Legacy Docket ID No. A-96-47) by one of the following 
methods:
     Federal eRulemaking Portal: https://www.regulations.gov. 
Follow the on-line instructions for submitting comments.
     Agency Web site: https://www.epa.gov/edocket. EDOCKET, 
EPA's electronic public docket and comment system, is EPA's preferred 
method for receiving comments. Follow the on-line instructions for 
submitting comments.
     E-mail: a-and-r-docket@epa.gov.
     Fax: (202) 566-1741.
     Mail: Air and Radiation Docket and Information Center, 
U.S. EPA, Mailcode: 6102T, 1200 Pennsylvania Avenue, NW., Washington, 
DC 20460.
     Hand Delivery: Air and Radiation Docket and Information 
Center, U.S. EPA, Room B102, 1301 Constitution Avenue, NW., Washington, 
DC. Such deliveries are only accepted during the Docket's normal hours 
of operation, and special arrangements should be made for deliveries of 
boxed information.
    Instructions. Direct your comments to Docket ID No. OAR-2002-0058 
(Legacy Docket ID No. A-96-47). 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 https://www.epa.gov/edocket, including any 
personal information provided, unless the comment includes information 
claimed to be Confidential Business Information (CBI) or other 
information whose disclosure is restricted by statute. Do not submit 
information that you consider to be CBI or otherwise protected through 
EDOCKET, regulations.gov, or e-mail. The EPA EDOCKET and the Federal 
regulations.gov Web sites are ``anonymous access'' systems, 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 EDOCKET or 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.
    Public Hearing. If a public hearing is held, it will be held on 
July 12, 2005 at the EPA facility, Research Triangle Park, N.C. or an 
alternative site nearby. Persons interested in attending the hearing or 
wishing to present oral testimony should notify Ms. Pamela Garrett 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 document.
    Docket. The EPA has established an official public docket for 
today's document, including both Docket ID No. OAR-2002-0058 and Legacy 
Docket ID No. A-96-47. The official public docket consists of the 
documents specifically referenced in today's document, any public 
comments received, and other information related to the document. All 
items may not be listed under both

[[Page 36908]]

docket numbers, so interested parties should inspect both docket 
numbers to ensure that they have received all materials relevant to 
today's document. Although listed in the index, some information is not 
publicly available, i.e., CBI or other information whose disclosure is 
restricted by statute. Certain other material, such as copyrighted 
material, is not placed on the Internet and will be publicly available 
only in hard copy form. Publicly available docket materials are 
available either electronically in EDOCKET or in hard copy at the Air 
and Radiation Docket and Information Center, U.S. EPA, Room B102, 1301 
Constitution Avenue, NW., Washington, DC. 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, and the telephone number for the Air and Radiation 
Docket and Information Center is (202) 566-1742.

FOR FURTHER INFORMATION CONTACT: For general and technical information, 
contact Mr. James Eddinger, Combustion Group, Emission Standards 
Division, Mailcode: C439-01, U.S. EPA, Research Triangle Park, NC 
27711; telephone number: (919) 541-5426; fax number: (919) 541-5450; e-
mail address: eddinger.jim@epa.gov. For questions about the public 
hearing, contact Ms. Pamela Garrett, Combustion Group, Emission 
Standards Division, Mailcode: C439-01, Environmental Protection Agency, 
Research Triangle Park, NC 27711; telephone number: (919) 541-7966; fax 
number: (919) 541-5450; e-mail address: garrett.pamela@epa.gov.

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

I. General Information
    A. Does This Reconsideration Notice Apply to Me?
    B. How Do I Submit CBI?
    C. How Do I Obtain a Copy of This Document and Other Related 
Information?
II. Background
III. Today's Action
    A. Grant of Reconsideration
    B. Request for Stay of Health-Based Alternatives
IV. Discussion of Issues Subject to Reconsideration
    A. Methodology and Criteria for Demonstrating Eligibility for 
the Health-based Compliance Alternatives
    B. Tiered Risk Assessment Methodology
    C. Look-Up Tables
    D. Site-Specific Risk Assessment
    E. Background Concentrations and Emissions From Other Sources
    F. Health-Based Compliance Alternative for Metals
    G. Deadline for Submission of Health-Based Applicability 
Determinations
    H. What Are the Proposed Corrections to the Health-Based 
Compliance Alternatives?
V. 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
    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 and Safety Risks
    H. Executive Order 13211: Actions That Significantly Affect 
Energy Supply, Distribution, or Use
    I. National Technology Transfer and Advancement Act

I. General Information

A. Does This Reconsideration Notice Apply to Me?

    Categories and entities potentially affected by today's document 
include:

----------------------------------------------------------------------------------------------------------------
                                                                               Examples of potentially regulated
                 Category                      SIC code a      NAICS code b                entities
----------------------------------------------------------------------------------------------------------------
Any industry using a boiler or process                   24              321  Manufacturers of lumber and wood
 heater as defined in the final rule                     26              322   products.
                                                         28              325  Pulp and paper mills.
                                                                              Chemical manufacturers.
                                                         29              324  Petroleum refineries, and
                                                                               manufacturers of coal products.
                                                         30    316, 326, 339  Manufacturers of rubber and
                                                                               miscellaneous plastic products.
                                                         33              331  Steel works.
                                                         34              332  Electroplating, plating,
                                                                               polishing, anodizing, and
                                                                               coloring.
                                                         37              336  Manufacturers of motor vehicle
                                                                               parts and accessories.
                                                         49              221  Electric, gas, and sanitary
                                                                               services.
                                                         80              622  Health services.
                                                         82              611  Educational services.
----------------------------------------------------------------------------------------------------------------
a Standard Industrial Classification.
b North American Industrial Classification System.

    This table is not intended to be exhaustive, but rather provides a 
guide for readers regarding entities likely to be affected by today's 
document. To determine whether your facility is affected by today's 
document, you should examine the applicability criteria in Sec.  
63.7485 of the final rule. If you have questions regarding the 
applicability of today's document to a particular entity, consult Mr. 
Jim Eddinger listed in the preceding FOR FURTHER INFORMATION CONTACT 
section.

B. How Do I Submit CBI?

    Do not submit this information to EPA through EDOCKET, 
regulations.gov, or e-mail. Clearly mark the part or all of the 
information that you claim to be CBI. For CBI 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 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.

C. 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 document also will be available on the World Wide Web (WWW) 
through EPA's Technology Transfer Network (TTN). Following the 
Administrator's signature, a copy of this document will be posted on 
the TTN's policy and guidance page for newly proposed rules at https://
www.epa.gov/ttn/oarpg. The TTN provides information and technology 
exchange in various areas of air pollution control.

II. Background

    On September 13, 2004 (69 FR 55218), we promulgated NESHAP for 
sources in the industrial, commercial, and institutional boilers and 
process heaters category pursuant to section 112 of the Clean Air Act 
(CAA). Under section 112(d) of the CAA, the NESHAP must

[[Page 36909]]

reflect the maximum degree of reduction in emissions of HAP that is 
achievable, taking into consideration the cost of achieving the 
emissions reductions, any non-air quality health and environmental 
impacts, and energy requirements. This level of control is commonly 
referred to as maximum achievable control technology (MACT). However, 
section 112(d)(4) of the CAA also states that ``[w]ith respect to 
pollutants for which a health threshold has been established, the 
Administrator may consider such threshold level, with an ample margin 
of safety, when establishing emissions standards under this 
subjection.''
    We proposed standards for industrial, commercial, and institutional 
boilers and process heaters on January 13, 2003 (68 FR 16660). The 
preamble for the proposed rule described the rationale for the proposed 
rule and solicited public comments. We requested comment on 
incorporating various risk-based approaches (based on section 112(d)(4) 
and other provisions of the CAA) into the final rule to reduce the cost 
of regulatory controls on those facilities that pose little risk to 
public health and the environment. (See 68 FR 1688-1693.) Industry 
trade associations, owners/operators of boilers and process heaters, 
State regulatory agencies, local government agencies, and environmental 
groups submitted comments on the proposed risk-based approaches. We 
received a total of 218 public comment letters on the proposed rule 
during the comment period. We summarized major public comments on the 
proposed risk-based approaches, along with our responses to those 
comments, in the preamble to the final rule (see 69 FR 55239-55244) and 
in the comment response memorandum, ``Response to Public Comments on 
Proposed Industrial, Commercial, and Institutional Boilers and Process 
Heaters NESHAP (Revised) (RTC Memorandum) that was placed in the docket 
for the final rule.
    In the final rule, we adopted health-based compliance alternatives 
for hydrogen chloride (HCl) and manganese based on our authority under 
sections 112(d)(4) of the CAA. Affected sources demonstrating that they 
are eligible for one or both of the health-based compliance 
alternatives are not required to demonstrate compliance with specific 
emissions limits in table 1 to the final rule. Affected sources that 
successfully demonstrate that they are eligible for the HCl health-
based compliance alternatives are not subject to the MACT HCl emission 
limit but are still subject to operating and monitoring requirements in 
the final rule (subpart DDDDD of 40 CFR part 63). With respect to 
manganese, affected sources that demonstrate eligibility for the 
health-based compliance alternative for total selected metals (TSM) are 
still subject to the MACT TSM emission limit and operating and 
monitoring requirements in the final rule (subpart DDDDD of 40 CFR part 
63) except that they may demonstrate compliance with the TSM emission 
limit based on the sum of emissions for seven metals, instead of the 
eight selected metals, by excluding manganese emissions.
    The methodology and criteria for affected sources to use in 
demonstrating eligibility for the health-based compliance alternatives 
were promulgated in appendix A to subpart DDDDD of 40 CFR part 63. (See 
69 FR 55282-55286.) Appendix A specifies the process units and 
pollutants that must be included in the eligibility demonstration, the 
emissions testing methods, the criteria for determining if an affected 
source is eligible, the risk assessment methodology (look-up table 
analysis or site-specific risk analysis), the contents of the 
eligibility demonstration, the schedule for submission of the self-
certified eligibility demonstrations, and the methods for ensuring that 
an affected source remains eligible.
    For an affected source to be eligible for the health-based 
compliance alternatives, it must submit a signed certification that the 
demonstration is an accurate depiction of the affected facility. 
Thereafter, it must have federally enforceable conditions reflecting 
the parameters used in the eligibility demonstration incorporated into 
its title V permit to ensure that it remains eligible.
    Following promulgation of the final rule, the Administrator 
received petitions for reconsideration pursuant to section 307(d)(7)(B) 
of the CAA from the Natural Resources Defense Council (NRDC), 
Environmental Integrity Project (EIP), and General Electric (GE).\1\ 
Under this provision, the Administrator is to initiate reconsideration 
proceedings if the petitioner can show 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.
---------------------------------------------------------------------------

    \1\ In addition to the petitions for reconsideration, two 
petitions for judicial review of the final rule were filed with the 
U.S. Court of Appeals for the District of Columbia by NRDC, Sierra 
Club, and EIP (No. 04-1385, D.C. Cir.) and American Municipal 
Power--Ohio and the Ohio cities of Dover, Hamilton, Orrville, 
Painesville, Shelby, and St. Marys (No. 04-1386, D.C. Cir.). The two 
cases have been consolidated. Eleven additional parties have filed 
petitions to intervene: American Home Furnishings Alliance, Council 
of Industrial Boiler Owners, American Forest and Paper Association, 
American Chemistry Council, National Petrochemical and Refiners 
Association, American Petroleum Institute, National Oilseed 
Processors Association, Coke Oven Environmental Task Force, Utility 
Air Regulatory Group, and Alliance of Automobile Manufacturers are 
intervening with regard to the health-based compliance alternatives.
---------------------------------------------------------------------------

    NRDC and EIP initially requested that EPA reconsider seven issues 
reflected in the final rule that they believe could not have been 
practicably addressed during the public comment period. EIP also filed 
a supplement to this petition which raised additional issues for 
reconsideration. Together, NRDC and EIP have requested reconsideration 
of the following issues: (1) The adoption of ``no control'' MACT floors 
for certain subcategories and pollutants; (2) establishing risk-based 
alternatives on a plant-by-plant basis; (3) the presence of health 
thresholds for HCl and manganese; (4) consideration of background 
pollution and co-located emission sources; (5) establishing a health-
based compliance alternative for a pollutant (HCl) that serves as a 
surrogate for other inorganic pollutants; (6) promulgating a health-
based compliance alternative that allows low-risk sources of manganese 
emissions to comply with the MACT limitations for metals without 
counting manganese; (7) the procedures for demonstrating compliance 
with the health-based alternatives; (8) consideration of emissions 
during periods of startup, shutdown, malfunction and (9) the cost-
effectiveness of the health-based alternatives. The NRDC and EIP 
petition also requested that EPA stay the effectiveness of the health-
based compliance alternatives pending reconsideration.
    By letters dated January 28, 2005, we informed NRDC and EIP that we 
intended to grant their joint petition for reconsideration. We 
indicated in those letters that we would respond to the petitions by 
publishing this document.

III. Today's Action

A. Grant of Reconsideration

    Today, we are granting reconsideration of several of the issues 
raised in the NRDC and EIP petition for reconsideration. As a result, 
we are requesting comment on certain provisions in appendix A of 
subpart DDDDD of 40 part 63 and the health-based compliance alternative 
for total selected metals reflected in Sec.  63.7507(b) of the final 
rule. We are continuing to review the issue raised by GE with respect 
to the emissions averaging provision of the final rule and are not

[[Page 36910]]

taking action on that petition at this time.\2\
---------------------------------------------------------------------------

    \2\ GE requested reconsideration of the emissions averaging 
provisions of the final rule to address how this provision might 
apply in the context of emissions units that vent to a single stack.
---------------------------------------------------------------------------

    Nearly all of the issues on which NRDC and EIP request 
reconsideration relate to the health-based compliance alternatives 
adopted in the final rule. Although we believe these aspects of the 
final rule are properly supported and justified, we recognize that the 
public may not have had the opportunity to comment on each of the 
implementation requirements for these alternatives that are reflected 
in the final rule because they were not completely developed by EPA at 
the time of the proposed rule. Section IV discusses the issues for 
which we are soliciting comment, including the methodology and criteria 
for demonstrating eligibility for the health-based compliance 
alternatives, the tiered risk assessment approach, look-up tables, 
site-specific risk assessment, background concentrations and emissions 
from other sources, submission deadlines, and the health-based 
compliance alternative for metals.
    We are not reconsidering the remaining issues raised by NRDC and 
EIP because we believe we provided clear notice and a full opportunity 
to comment on these aspects of the final rule. We proposed ``no 
emissions control'' floors in our January 2003 action and received 
comments on this issue. (See 68 FR 1672-1678; 69 FR 55233; RTC 
Memorandum at 78-79.) We also proposed to establish plant-by-plant 
health-based alternatives under the authority of section 112(d)(4) of 
the CAA and thoroughly explained why this action is legally permissible 
in response to comments on this issue (69 FR 55239-44). (See also RTC 
Memorandum at 185-269.) Likewise, we proposed health-based compliance 
alternatives for HCl and proposed using HCl as a surrogate to regulate 
other inorganic pollutants. (See 68 FR 1671, 1692.) We received and 
responded to comments raising concerns about combining these two 
concepts in the rule, as proposed, and addressed this issue when we 
developed appendix A to subpart DDDDD. (See 69 FR 55243-55244.) We 
identified the Integrated Risk Information System (IRIS) reference 
concentrations for HCl and manganese in the notice of proposed 
rulemaking (68 FR 1690). These values were established through a 
process conducted by EPA's Office of Research and Development in which 
there was opportunity for public participation (e.g., 58 FR 11490 
(February 25, 1993). The IRIS process is a rigorous scientific process 
which includes internal peer review, external scientific peer review 
combined with public notice, and often includes outside peer 
consultation to support the development of dose-response knowledge.
    Commenters also had an opportunity to address our treatment of 
emissions during periods of startup, shutdown, and malfunction and the 
cost-effectiveness of the proposed rule. We received and responded to 
several comments regarding startup, shutdown, and malfunction plans. 
(See RTC at 144-155 (section 12)). We assessed the costs and benefits 
of the final rule in the preamble to the final rule (69 FR 55245-55247) 
and the supporting documentation ``Regulatory Impact Analysis for the 
Final Industrial, Commercial, and Institutional Boilers and Process 
Heaters MACT'' that was included in the docket.

B. Request for Stay of Health-Based Alternatives

    We are not granting the request by NRDC and EIP for a stay of the 
health-based compliance alternatives. Under section 307(b)(1) and 
307(d)(7)(B) of the CAA, the effectiveness of our final rules is not 
automatically postponed by our granting of a petition for 
reconsideration on certain issues. However, the Administrator has the 
discretion to stay such rules pending reconsideration for a period not 
to exceed 3 months.
    We do not believe it is necessary in this instance to stay the 
health-based compliance alternatives. Although we have decided to 
reconsider certain aspects concerning the implementation of these 
alternatives, we do not have reason to believe that approaches 
reflected in these provisions are erroneous. We regard these aspects of 
the final rule as a reasonable exercise of our discretion and authority 
under the CAA that will reduce compliance costs for sources.
    The public health is not endangered by the continued effectiveness 
of the health-based compliance alternatives during the reconsideration 
process. A facility cannot invoke this alternative compliance option 
unless it demonstrates to the appropriate permitting authority that its 
emissions exhibit characteristics that EPA believes do not pose 
significant risk to the surrounding population. In addition, the 
compliance date for existing sources is in 2007, so the health-based 
compliance alternatives will not be applied to such sources 
immediately.
    Finally, we intend to complete our reconsideration of the final 
rule expeditiously. Any uncertainty that may be created by our partial 
granting of these petitions for reconsideration will be short-lived.
    Thus, at this time we do not propose to change the compliance date 
for the final rule or the date for submittal of health-based 
eligibility demonstrations. However, we request comment on whether, in 
light of the time required to complete this reconsideration action, we 
should adjust the timetable for submission of these eligibility 
determinations.

IV. Discussion of Issues Subject to Reconsideration

    Stakeholders who would like for us to reconsider comments relevant 
to those issues that they submitted to us previously 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. Methodology and Criteria for Demonstrating Eligibility for the 
Health-Based Compliance Alternatives

    In the final rule, we established emissions limitations for 
particulate matter (PM), TSM, HCl, mercury, and carbon monoxide based 
on MACT. These limitations are set forth in table 1 to subpart DDDDD. 
In addition, based on section 112(d)(4) of the CAA, we also established 
health-based compliance alternatives to the HCl and TSM emissions 
limitations, which are set forth in Sec.  63.7507 of subpart DDDDD. 
Under these alternatives, an affected source that qualifies may 
demonstrate compliance with a health-based HCl equivalent allowable 
emission limit instead of the emissions limitation for HCl set forth in 
table 1. For TSM, an affected source that qualifies may demonstrate 
compliance with the emission standard for TSM in the final rule based 
on the sum of emissions for the seven selected metals, excluding 
manganese emissions from the summation of TSM emissions for the 
affected source.
    In our notice of proposed rulemaking, we described approaches that 
we might use to implement an applicability cutoff for threshold 
pollutants based on section 112(d)(4) of the CAA. (See 68 FR 1689-
1692.) We discussed establishing the applicability cutoffs using a 
target organ specific HI, which is the sum of the individual hazard 
quotients (HQ) for pollutants that affect the same target organ or 
system. A HQ is the ratio of the level of exposure for a single 
substance over a specified time period to a reference level (e.g., 
EPA's reference

[[Page 36911]]

concentration, or RfC) for that substance derived for a similar 
exposure period. The RfC is an estimate of a continuous inhalation 
exposure or a daily exposure to the human population (including 
sensitive subgroups) that is likely to be without an appreciable risk 
of deleterious non-cancer effects during a lifetime. (See 69 FR 1689.) 
In addition, we discussed the possibility of developing a series of 
simple look-up tables that a facility could use to determine whether 
emissions from a source might cause a hazard index limit to be 
exceeded. (See 69 FR 1691.) In addition, we also discussed the 
possibility that a facility that did not pass the look-up table 
analysis might be able to demonstrate that the facility does not exceed 
the HI limit by conducting a more site-specific and resource-intensive 
analysis using EPA-approved modeling procedures. (See 69 FR 1691.)
    In the final rule, we established procedures for demonstrating 
eligibility for the health-based compliance alternatives and codified 
them in appendix A of subpart DDDDD. These procedures are summarized in 
the preamble to the final rule (69 FR 55227-55228). The preamble to the 
final rule also contained a summary of our response to significant 
comments. (See 69 FR 55239-55244.)
    We are requesting comment on specific aspects of the methodology 
reflected in appendix A, as discussed in more detail in the following 
sections.

B. Tiered Risk Assessment Methodology

    As noted above, appendix A to subpart DDDDD employs a tiered 
analytical approach to determine whether a facility is eligible for the 
health-based compliance alternatives. We explained in our notice of 
proposed rulemaking that a tiered analysis involves making successive 
refinements in modeling methodologies and input data such that 
increasing levels of refinement require more site-specific data and 
are, therefore, less likely to overestimate risks. (See 68 FR 1691.)
    Additionally, in our notice of proposed rulemaking, we indicated 
that EPA guidance could provide the basis for conducting a tiered 
analysis. (See 68 FR 1691.) Such guidance may be found in the document 
``A Tiered Modeling Approach for Assessing the Risks due to Sources of 
Hazardous Air Pollutants,'' EPA-450/4-92-001 that we referenced in a 
footnote. Although it was clearly referenced in the proposal, we 
inadvertently failed to place this document in the docket for the 
proposed rulemaking. It is now in the docket.
    Appendix A describes a tiered approach where sources can utilize 
the health-based alternative compliance options by performing either a 
look-up table analysis or a more detailed site-specific analysis. Thus, 
a source would start with a modeling strategy that requires very little 
site-specific data and makes health-protective assumptions (e.g. look-
up tables). At more refined tiers, the assessment becomes more 
realistic (e.g. less likely to overestimate risks) but it requires more 
site-specific data and possibly more sophisticated models. Thus, higher 
tier assessments result in a more realistic assessment of risk but 
require more data and are more labor intensive to conduct.
    In the implementation of this approach in the final rule, we did 
two things: (1) We created look-up tables specific to this source 
category, eliminating the need to use the generic look-up table in the 
proposed reference, and (2) we referred the user requiring more refined 
tiers of analysis to our recently published Air Toxics Risk Assessment 
Reference Library, Volume 2, Facility-specific Assessment, a document 
which builds off the earlier EPA guidance document (the one referenced 
in the proposal), implementing the tiered approach in the context of a 
facility-specific risk assessment for air toxics. Both of these 
documents endorse the assessment of air toxics risks using a tiered, 
iterative approach, and that has been the preferred approach ever since 
it was endorsed by the National Academy of Sciences in their report, 
``Science and Judgment in Risk Assessment,'' NRC press, 1994.
    In response to the concerns expressed by the petitioners, we have 
entered the document ``A Tiered Modeling Approach for Assessing the 
Risks Due to Sources of Hazardous Air Pollutants'' into the docket for 
public review. We request comment on the use of a tiered analysis in 
appendix A and the application in this case of the principles set forth 
in the aforementioned document.

C. Look-Up Tables

    In the notice of proposed rulemaking, for the first tier of a risk 
assessment analysis for threshold pollutants, we proposed to develop a 
series of simple look-up tables based on the results of air dispersion 
modeling using conservative input assumptions. We proposed to create 
tables using a limited number of parameters (such as stack height, 
distance to property line, and emissions rate) that could be used to 
easily determine whether emissions from a source might cause a HI limit 
to be exceeded. (See 68 FR 1691.)
    In the final rule, we promulgated specific look-up tables for HC1 
and manganese that provide allowable emissions rate values for several 
combinations of stack heights and distances to a property boundary. 
(See 69 FR 55286.) A source is eligible for the compliance alternatives 
if its calculated emission rate does not exceed the appropriate value 
in the look-up table.
    We developed the look-up tables for hydrogen chloride and manganese 
in appendix A to subpart DDDDD using the health-protective SCREEN3 air 
dispersion model. A description of the method we used to develop the 
look-up tables is set forth in a memorandum in the docket entitled 
``Development of Central Nervous System and Respiratory System Look-up 
Tables for Industrial Boilers.'' We ran dispersion models using health-
protective assumptions that we believe are appropriate for a screening 
analysis such as the one set forth in appendix A to subpart DDDDD.
    The look-up table for HCl was developed based on an evaluation of 
not just HCl, but all acid gas and respiratory HAP. Likewise, the look-
up table for manganese was developed based on an assessment of not just 
manganese emissions, but all central nervous system HAP emissions.
    We used average stack height because, based on available stack 
height information for several facilities, we found that the stacks 
heights of multiple solid fuel units at a given facility are generally 
similar. In light of this finding and health-protective assumptions 
built into the look-up tables, we believe that using average stack 
height will not understate the risks posed by each source.
    We request comment on the look-up tables and the methodology used 
to develop them. This includes our use of average stack heights, the 
derivation of different look-up table values based on distance from the 
property line, and the use of conservative assumptions to account for 
other variables such as meteorology.

D. Site-Specific Risk Assessment

    If a facility cannot show eligibility for a compliance alternative 
based on the look-up table, it may conduct a more refined site-specific 
risk assessment in accordance with section 7 of appendix A to subpart 
DDDDD. (See 69 FR 55283.) Under this approach, a facility must use any 
scientifically-defensible, transparent and peer-reviewed assessment 
methodology to determine risk from the facility. The facility is 
eligible for the alternative compliance

[[Page 36912]]

option if the site-specific risk assessment shows that the maximum HI 
(or HQ) from the affected sources at the facility is less than or equal 
to 1.0.
    An example of site-specific modeling performed in accordance with 
the principles set forth in appendix A to subpart DDDDD is described in 
the EPA ``Air Toxics Risk Assessment Reference Library'' which is 
referenced in section 7 of appendix A. The library includes examples of 
how to estimate inhalation exposures and other parameters.
    Our approach in appendix A to subpart DDDDD is based on the general 
air toxics risk assessment approach presented in EPA's Residual Risk 
Report to Congress (available at https://www.epa.gov/ttn/oarpg/t3/
reports/risk_rep.pdf). The Air Toxics Risk Assessment Reference 
Library has been peer-reviewed and was developed according to the 
principles, tools and methods outline in the Residual Risk Report to 
Congress.
    For accuracy, a facility is required to use site-specific and 
quality-assured data whenever possible. Selection of site-specific 
input parameters is the essence of this site-specific demonstration. As 
a result, section 7(c)(5) of appendix A to subpart DDDDD requires 
adequate documentation for all inputs and assumptions.
    We request comment on the approach for conducting a site-specific 
risk assessment and the criteria set forth in section 7 of appendix A 
to subpart DDDDD.

E. Background Concentrations and Emissions From Other Sources

    In our notice of proposed rulemaking, we discussed using a HI to 
identify the applicability cutoff for a standard for threshold 
pollutants based on section 112(d)(4) of the CAA. (See 68 FR 1689-
1691.) One option that we discussed was using a HI of 1.0. (See 68 FR 
1691.) A second option that we discussed was using a HI of less than 
1.0, such as 0.2, which would reflect an assumption that 20 percent of 
individual's total exposure comes from a particular source, and that 80 
percent of the exposure would result from background concentrations of 
pollutants resulting from other sources. We also discussed the option 
of using available data from scientific literature to determine a 
background concentration. (See 68 FR 1691.)
    In the final rule, we decided to employ a HI or HQ of 1.0 as the 
applicability cutoff for the assessments performed via appendix A to 
subpart DDDDD. The look-up tables included in appendix A were developed 
based on an HI of 1.0 for HCl and chlorine, and an HQ of 1.0 for 
manganese. For a site-specific compliance demonstration under section 7 
of appendix A, a source must demonstrate that the subpart DDDDD, 40 CFR 
part 63, units at the facility are not expected to cause an individual 
chronic inhalation exposure from HCl and chlorine that exceeds an HI of 
1.0 or an individual chronic inhalation exposure from manganese which 
could exceed an HQ of 1.0.
    We concluded that an HI (or HQ) limit of 1.0 was appropriate for 
the CAA section 112(d)(4) demonstration for the boiler and process 
heater source category because the RfCs that are used to calculate the 
HI and HQ are developed to protect sensitive subgroups and to account 
for scientific uncertainties. We believe this ensures that a HI limit 
of 1.0 provides an ample margin of safety. (See RTC Memorandum at 253.)
    Additionally, we decided not to consider the impact of non-boiler-
related background emissions in the implementation of the health-based 
compliance alternatives for HCl and manganese, indicating instead our 
intent to assess facility-wide emissions of HAP in future residual risk 
actions under section 112(f)(2) of the CAA, to the extent it is 
appropriate and reasonable to do so. (See RTC Memorandum at 253.)
    Although we indicated that one option for addressing background 
emissions was to utilize an HI of 0.2, we did not intend to suggest 
that this was the only reasonable approach for addressing the potential 
risk from background emissions. After evaluating comments on this 
issue, we are satisfied that an HI or HQ of 1.0 is appropriate.
    To ensure that we receive input from members of the public that 
wish to be heard, we are requesting comment on our approach. We also 
request comment on deferring any further consideration of background 
and co-located sources until we assess facility-wide emissions of HAP 
in future residual risk actions under section 112(f)(2) of the Clean 
Air Act.

F. Health-Based Compliance Alternative for Metals

    The final regulations in subpart DDDDD include a health-based 
compliance alternative for TSM in Sec.  63.7507(b). Applicability for 
this alternative is determined on the basis of the levels of emissions 
of manganese from affected sources, in accordance with appendix A to 
subpart DDDDD. A source that demonstrates eligibility for this health-
based alternative is permitted to exclude manganese from its 
calculation of TSM to show compliance with the emissions limitations in 
table 1 to subpart DDDDD. Thus, under the health-based alternative for 
TSM, the source is in compliance with subpart DDDDD of 40 CFR part 63 
if the total emissions of seven metals (rather than eight) meet the 
emissions limitations for TSM in table 1 to subpart DDDDD.
    In the notice of proposed rulemaking (68 FR 1689), we proposed to 
establish an applicability cutoff for threshold pollutants under 
section 112(d)(4) of the CAA. We listed dose-response assessment values 
for the HAP emitted by the boiler and process heater source category. 
(See 68 FR 1690, table 4.) The table listing these values included the 
reference concentrations for several pollutants, including manganese.
    Although we specifically proposed in the preamble to the notice of 
proposed rulemaking to establish an applicability cutoff for HCl under 
section 112(d)(4) of the CAA, we intended to request comment on using 
this approach for all threshold pollutants. Indeed, we received several 
comments that addressed additional pollutants besides HCl, including 
manganese. (See RTC Memorandum and Docket ID No. OAR-2002-0058.) Based 
on these comments and our analysis, we concluded in the final rule that 
it was appropriate to include a health-based compliance alternative for 
manganese as well. Because manganese is one of the HAP metals emitted 
by sources in the boilers and process heaters category, we promulgated 
a health-based alternative emissions limitations for TSM.
    To establish the health-based alternative emissions limitations for 
TSM, we performed the same MACT floor analysis as was conducted, and 
described in the proposal preamble, for the proposed TSM emission 
limit. This approach is described in the memorandum ``Revised MACT 
Floor Analysis for the Industrial, Commercial, and Institutional 
Boilers and Process Heaters National Emission Standards for Hazardous 
Air Pollutants Based on Public Comments'' and appendix C-2 to that 
memorandum, which is contained in the docket.
    We request comment on both the appropriateness of adopting a 
health-based compliance alternative for manganese and, under this 
alternative, using the same TSM emission limit in table 1 to subpart 
DDDDD as a limitation for seven metals, while excluding manganese from 
the calculation.

G. Deadline for Submission of Health-Based Applicability 
Determinations.

    Under section 9(a) of appendix A to subpart DDDDD, existing sources 
must submit their eligibility demonstration to

[[Page 36913]]

a permitting authority no later than the date 1 year prior to the 
compliance date of subpart DDDDD. Pursuant to Sec.  63.7495(b) of the 
subpart DDDDD, the compliance date for existing sources is September 
13, 2007. Thus, existing sources must submit their compliance 
demonstrations under appendix A by September 13, 2006.
    Several representatives of the regulated industry have expressed 
concern that EPA's reconsideration of certain aspects of appendix A to 
subpart DDDDD will make it difficult to make the eligibility 
demonstration by September 13, 2006. These parties are concerned that 
the uncertainty created by this reconsideration action will make it 
difficult to complete an eligibility demonstration by September 13, 
2006.
    EPA does not believe that this reconsideration action makes it 
necessary to provide regulated sources with more time to prepare their 
eligibility demonstrations. Sources should proceed to prepare their 
eligibility demonstrations under the existing process promulgated in 
the final rule. We believe that the existing process in appendix A is 
supported by the record, and do not at this time have reason to believe 
changes will be necessary.
    To the extent we determine, based on comments submitted in response 
to this action, that changes are needed to appendix A to subpart DDDDD, 
we will evaluate whether, based on the significance of any change, 
additional time is needed.
    However, we will also need to consider the competing considerations 
which lead us to establish this date 1 year before the compliance date 
in the first instance. We believe 1 year is necessary in order to 
provide permitting authorities with enough time to evaluate the 
eligibility demonstrations and sources with enough time to comply with 
the MACT emissions limitations, if their eligibility demonstration is 
not accepted.
    Based on section 112(i)(3)(A) of the CAA, which states that EPA 
cannot establish a compliance date later than 3 years after the 
effective date of the final rule, we do not believe we are authorized 
to extend the compliance date for existing sources beyond September 13, 
2007. However, under section 112(i)(3)(B) of the CAA, permitting 
authorities may be authorized to grant up to 1 additional year to 
comply where a source can demonstrate that such time is necessary for 
the installation of controls.
    Thus, we do not believe it is appropriate at this time to propose 
any adjustment to the deadline for submitting eligibility 
demonstrations. However, because of the concern over this timing, we 
request comment on whether we should or should not extend the deadline 
for submission of eligibility demonstrations in light of this 
reconsideration action.

H. What Are the Proposed Corrections to the Health-based Compliance 
Alternatives?

    We made an error in Sec.  63.7507(a) and the title of appendix A to 
subpart DDDDD that has caused confusion regarding the intended 
applicability of the health-based compliance alternative. As indicated 
in Sec.  63.7507(b) and the text of appendix A, the health-based 
compliance alternatives, both for HCl and TSM, were intended to be 
applicable to any affected source subject to the HCl and TSM emission 
limits in table 1 to subpart DDDDD. In Sec.  63.7507(a) and in the 
title of appendix A, we erroneously stated that the health-based 
compliance alternatives were only for the large solid fuel subcategory. 
Large solid fuel units are the main subcategory potentially affected by 
the health-based compliance alternatives but they are not the only 
subcategory having applicable HCl and TSM emission limits. We corrected 
that error by deleting the words ``for large solid fuel boilers located 
at a single facility'' from Sec.  63.7507(a) and deleted the words 
``Specified for the Large Solid Fuel Subcategory'' from the title of 
appendix A.
    These proposed corrections are intended to clarify, but not change, 
the coverage of the final rule. The corrections will not affect the 
estimated emissions reductions or the control costs for the final rule. 
The clarifications and corrections should make it easier for owners and 
operators and for local and State authorities to understand and 
implement the requirements.

VII. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review

    Under Executive Order 12866 (58 FR 51735, October 4, 1993), EPA 
must determine whether the regulatory action is ``significant'' and, 
therefore, subject to review by the Office of Management and Budget 
(OMB) and the requirements of the Executive Order. The Executive Order 
defines a ``significant regulatory action'' as one that is likely to 
result in a rule that may:
    (1) Have an annual effect on the economy of $100 million or more or 
adversely affect in a material way the economy, a sector of the 
economy, productivity, competition, jobs, the environment, public 
health or safety, or State, local, or tribal governments or 
communities;
    (2) create a serious inconsistency or otherwise interfere with an 
action taken or planned by another agency;
    (3) materially alter the budgetary impact of entitlement, grants, 
user fees, or loan programs, or the rights and obligations of 
recipients thereof; or
    (4) raise novel legal or policy issues arising out of legal 
mandates, the President's priorities, or the principles set forth in 
the Executive Order.
    Pursuant to the terms of Executive Order 12866, it has been 
determined that today's notice of reconsideration is a ``significant 
regulatory action'' because it raises novel legal or policy issues. As 
such, the action was submitted to OMB for review under Executive Order 
12866. Changes made in response to OMB suggestions or recommendations 
are documented in the public record (see ADDRESSES section of this 
preamble).

B. Paperwork Reduction Act

    The information collection requirements in the final rule were 
submitted for approval to OMB under the provisions of the Paperwork 
Reduction Act, 44 U.S.C. 3501 et seq. (Information Collection Request 
No. 2028.01). The information collection requirements are not 
enforceable until OMB approves them.
    Today's notice of reconsideration imposes no new information 
collection requirements on the industry. Because there is no additional 
burden on the industry as a result of the notice of reconsideration, 
the information collection request (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

[[Page 36914]]

unless it displays a currently valid OMB control number. The OMB 
control numbers for EPA's regulations are listed in 40 CFR part 9 and 
48 CFR chapter 15.

C. Regulatory Flexibility Act

    The Regulatory Flexibility Act 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 not-for-profit 
enterprises, and small governmental jurisdictions.
    For purposes of assessing the impacts of today's notice of 
reconsideration on small entities, a small entity is defined as: (1) A 
small business having no more 500 to 750 employees, depending on the 
business' NAICS code; (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 owned and 
operated and that is not dominant in its field.
    After considering the economic impacts of today's notice of 
reconsideration on small entities, we certify that the notice will not 
have a significant economic impact on a substantial number of small 
entities. The EPA has determined that none of the small entities will 
experience a significant impact because the notice of reconsideration 
imposes no additional regulatory requirements on owners or operators of 
affected sources.

D. Unfunded Mandates Reform Act

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public 
Law 104-4, establishes requirements for Federal agencies to assess the 
effects of their regulatory actions on State, local, and tribal 
governments and the private sector. Under section 202 of the UMRA, EPA 
generally must prepare a written statement, including a cost-benefit 
analysis, for proposed and final rules with ``Federal mandates'' that 
may result in expenditures by State, local, and tribal governments, in 
the aggregate, or by the private sector, of $100 million or more in any 
1 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's regulatory proposals with 
significant Federal intergovernmental mandates, and informing, 
educating, and advising small governments on compliance with the 
regulatory requirements.
    The 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, and tribal governments, in the 
aggregate, or the private sector in any 1 year. Although the final rule 
had annualized costs estimated to range from $690 to $860 million 
(depending on the number of facilities eventually demonstrating 
eligibility for the health-based compliance alternatives), today's 
notice of reconsideration does not add new requirements that would 
increase this cost. Thus, today's notice of reconsideration is not 
subject to the requirements of sections 202 and 205 of the UMRA. In 
addition, EPA has determined that today's notice of reconsideration 
does not significantly or uniquely affect small governments because it 
contains no requirements that apply to such governments or impose 
obligations upon them. Therefore, today's notice of reconsideration is 
not subject to section 203 of the UMRA.

E. Executive Order 13132: Federalism

    Executive Order 13132 (64 FR 43255, August 10, 1999) requires EPA 
to develop an accountable process to ensure ``meaningful and timely 
input by State and local officials in the development of regulatory 
policies that have federalism implications.'' ``Policies that have 
federalism implications'' are defined in the Executive Order to include 
regulations that have ``substantial direct effects on the States, on 
the relationship between the national government and the States, or on 
the distribution of power and responsibilities among the various levels 
of government.''
    Today's notice of reconsideration 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. 
None of the affected facilities are owned or operated by State 
governments, and the requirements discussed in today's notice will not 
supersede State regulations that are more stringent. Thus, Executive 
Order 13132 does not apply to today's notice of reconsideration.

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

    Executive Order 13175 (65 FR 67249, November 6, 2000) requires EPA 
to develop an accountable process to ensure ``meaningful and timely 
input by tribal officials in the development of regulatory policies 
that have tribal implications.'' ``Policies that have tribal 
implications'' are defined in the Executive Order to include 
regulations that have ``substantial direct effects on one or more 
Indian tribes, on the relationship between the Federal government and 
Indian tribes, or on the distribution of power and responsibilities 
between the Federal government and Indian tribes.''
    Today's notice of reconsideration does not have tribal 
implications. It will not have substantial direct effects on tribal 
governments, on the relationship between the Federal government and 
Indian tribes, or on the distribution of power and responsibilities 
between the Federal government and Indian tribes, as specified in 
Executive Order 13175. No affected facilities are owned or operated by 
Indian tribal governments. Thus, Executive Order 13175 does not apply 
to today's notice of reconsideration.

G. Executive Order 13045: Protection of Children From Environmental 
Health and Safety Risks

    Executive Order 13045 (62 FR 19885, April 23, 1997) applies to any 
rule that: (1) Is determined to be ``economically significant,'' as 
defined under Executive Order 12866, and (2) concerns an environmental 
health or safety risk that EPA has reason to believe may have a 
disproportionate effect on children. If the regulatory action meets 
both criteria, EPA must evaluate the environmental health or safety 
effects of the planned

[[Page 36915]]

rule on children and explain why the planned regulation is preferable 
to other potentially effective and reasonably feasible alternatives 
considered by EPA.
    Today's notice of reconsideration is not subject to the Executive 
Order because EPA does not have reason to believe that the 
environmental health or safety risks associated with the emissions 
addressed by this document present a disproportionate risk to children. 
This demonstration is based on the fact that the noncancer human health 
values we used in our analysis at promulgation (e.g., reference 
concentrations) are determined to be protective of sensitive 
subpopulations, including children. Also, while the cancer human health 
values do not always expressly account for cancer effects in children, 
the cancer risks posed by facilities that meet the eligibility criteria 
for the health-based compliance alternatives will be sufficiently low 
so as not to be a concern for anyone in the population, including 
children.

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

    Today's notice of reconsideration is not a ``significant energy 
action'' as defined in Executive Order 13211 (66 FR 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 conclude that 
today's notice of reconsideration is not likely to have any adverse 
energy effects.

I. National Technology Transfer and Advancement Act

    As noted in the final rule, section 12(d) of the National 
Technology Transfer and Advancement Act (NTTAA) of 1995 (Public Law No. 
104-113; 15 U.S.C. 272 note) directs EPA to use voluntary consensus 
standards in their regulatory and procurement activities unless to do 
so would be inconsistent with applicable law or otherwise 
impracticable. Voluntary consensus standards are technical standards 
(e.g., material specifications, test methods, sampling procedures, 
business practices) developed or adopted by one or more voluntary 
consensus bodies. The NTTAA requires EPA to provide Congress, through 
the OMB, with explanations when EPA 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 three voluntary consensus standards that were considered 
practical alternatives to the specified EPA test methods. An assessment 
of these and other voluntary consensus standards is presented in the 
preamble to the final rule (69 FR 55251, September 13, 2004).
    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 document.

List of Subjects in 40 CFR Part 63

    Environmental protection, Administrative practice and procedure, 
Air pollution control, Hazardous substances, Intergovernmental 
relations, Reporting and recordkeeping requirements.

    Dated: June 20, 2005.
Stephen L. Johnson,
Administrator.
    For the reasons stated in the preamble, title 40, chapter 1, of the 
code of Federal Regulations is proposed to be amended as follows:

PART 63--[AMENDED]

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

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

Subpart DDDDD--[Amended]

    2. Section 63.7507 is amended by revising paragraph (a) to read as 
follows:


Sec.  63.7507  What are the health-based compliance alternatives for 
the hydrogen chloride (HCl) and total selected metals (TSM) standards?

    (a) As an alternative to the requirement to demonstrate compliance 
with the HCl emission limit in table 1 to this subpart, you may 
demonstrate eligibility for the health-based compliance alternative for 
HCl emissions under the procedures prescribed in appendix A to this 
subpart.
* * * * *
    3. Appendix A to subpart DDDDD is amended by revising the heading 
to read as follows:

Appendix A to Subpart DDDDD--Methodology and Criteria for Demonstrating 
Eligibility for the Health-Based Compliance Alternatives

* * * * *
[FR Doc. 05-12662 Filed 6-24-05; 8:45 am]
BILLING CODE 6560-50-P