New Source Performance Standards Review for Nonmetallic Mineral Processing Plants; and Amendment to Subpart UUU Applicability, 21559-21577 [E8-8677]

Agencies

• ENVIRONMENTAL PROTECTION AGENCY

[Federal Register Volume 73, Number 78 (Tuesday, April 22, 2008)]
[Proposed Rules]
[Pages 21559-21577]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E8-8677]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 60

[EPA-HQ-OAR-2007-1018; FRL-8556-3]
RIN 2060-AO41


New Source Performance Standards Review for Nonmetallic Mineral 
Processing Plants; and Amendment to Subpart UUU Applicability

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: EPA is proposing amendments to the Standards of Performance 
for Nonmetallic Mineral Processing Plant(s) (NMPP). These proposed 
amendments include proposed revisions to the emission limits for NMPP 
affected facilities which commence construction, modification, or 
reconstruction after today's date (referred to as ``future'' affected 
facilities in this preamble). These proposed amendments for NMPP also 
include additional testing and monitoring requirements for future 
affected facilities; exemption of affected facilities that process wet 
material from this proposed rule; changes to simplify the notification 
requirements for all affected facilities; and changes to definitions 
and various clarifications. EPA is also proposing an amendment to the 
Standards of Performance for Calciners and Dryers in Mineral Industries 
to address applicability of this proposed rule to thermal sand 
reclamation processes at metal foundries.

DATES: Comments must be received on or before June 23, 2008, unless a 
public hearing is requested by May 2, 2008. If a hearing is requested 
on this proposed rule, written comments must be received by June 6, 
2008. Under the Paperwork Reduction Act, comments on the information 
collection provisions must be received by the Office of Management and 
Budget (OMB) on or before May 22, 2008.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2007-1018, by one of the following methods:
     www.regulations.gov: Follow the on-line instructions for 
submitting comments.
     E-mail: a-and-r-docket@epa.gov.
     Fax: (202) 566-1741.
     Mail: U.S. Postal Service, send comments to: EPA Docket 
Center (6102T), New Source Performance Standards for Nonmetallic 
Mineral Processing Plants Docket, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460. Please include a total of two copies. In 
addition, please mail a copy of your comments on the information 
collection provisions to the Office of Information and Regulatory 
Affairs, Office of Management and Budget (OMB), Attn: Desk Officer for 
EPA, 725 17th St., NW., Washington, DC 20503.
     Hand Delivery: In person or by courier, deliver comments 
to: EPA Docket Center (6102T), New Source Performance Standards for 
Nonmetallic Mineral Processing Plants Docket, EPA West, Room 3334, 1301 
Constitution Avenue, NW., 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.
    Instructions: Direct your comments to Docket ID No. EPA-HQ-OAR-
2007-1018. 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 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 www.regulations.gov or e-mail. 
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.
    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 
whose disclosure 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 EPA Docket Center, 
Standards of Performance for Nonmetallic Mineral Processing Plants 
Docket, EPA West, Room 3334, 1301 Constitution Ave., 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

[[Page 21560]]

(202) 566-1744, and the telephone number for the Docket Center is (202) 
566-1742.

FOR FURTHER INFORMATION CONTACT: Mr. Bill Neuffer, Office of Air 
Quality Planning and Standards, Sector Policies and Programs Division, 
Metals and Minerals Group (D243-02), Environmental Protection Agency, 
Research Triangle Park, NC 27711, telephone number: (919) 541-5435; fax 
number: (919) 541-3207; e-mail address: neuffer.bill@epa.gov.

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

I. General Information
    A. Does this action apply to me?
    B. What should I consider as I prepare my comments to EPA?
    C. Where can I get a copy of this document?
    D. When would a public hearing occur?
II. Background Information on Subpart OOO
    A. What is the statutory authority for these proposed amendments 
to subpart OOO?
    B. What are the current NMPP NSPS?
III. Summary of these Proposed Amendments to Subpart OOO
IV. Rationale for These Proposed Amendments to Subpart OOO
    A. How is EPA proposing to change the emission limits for future 
affected facilities?
    B. How is EPA proposing to amend subpart OOO applicability and 
definitions?
    C. How is EPA proposing to amend the testing requirements?
    D. How is EPA proposing to amend the monitoring requirements?
    E. How is EPA proposing to amend the notification, reporting and 
recordkeeping requirements?
V. Modification and Reconstruction Provisions
VI. Clarifications on Subpart OOO
VII. Summary of Cost, Environmental, Energy, and Economic Impacts of 
These Proposed Amendments to Subpart OOO
    A. What are the impacts for NMPP?
    B. What are the secondary impacts?
    C. What are the economic impacts?
VIII. Proposed Amendment to Subpart UUU Applicability
IX. 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 Risks and Safety Risks
    H. Executive Order 13211: Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use
    I. National Technology Transfer Advancement Act
    J. Executive Order 12898: Federal Actions to Address 
Environmental Justice in Minority Populations and Low-Income 
Populations

I. General Information

A. Does this action apply to me?

    Categories and entities potentially regulated by these proposed 
amendments include:

------------------------------------------------------------------------
                                                   Examples of regulated
           Category               NAICS code\1\           entities
------------------------------------------------------------------------
Industry......................  212311...........  Dimension Stone
                                                    Mining and
                                                    Quarrying.
                                212312...........  Crushed and Broken
                                                    Limestone Mining and
                                                    Quarrying.
                                212313...........  Crushed and Broken
                                                    Granite Mining and
                                                    Quarrying.
                                212319...........  Other Crushed and
                                                    Broken Stone Mining
                                                    and Quarrying.
                                212321...........  Construction Sand and
                                                    Gravel Mining.
                                212322...........  Industrial Sand
                                                    Mining.
                                212324...........  Kaolin and Ball Clay
                                                    Mining.
                                212325...........  Clay and Ceramic and
                                                    Refractory Minerals
                                                    Mining.
                                212391...........  Potash, Soda, and
                                                    Borate Mineral
                                                    Mining.
                                212393...........  Other Chemical and
                                                    Fertilizer Mineral
                                                    Mining.
                                212399...........  All Other Nonmetallic
                                                    Mineral Mining.
                                221112...........  Fossil-Fuel Electric
                                                    Power Generation.
                                324121...........  Asphalt Paving
                                                    Mixture and Block
                                                    Manufacturing.
                                327121...........  Brick and Structural
                                                    Clay Tile
                                                    Manufacturing.
                                327122...........  Ceramic Wall and
                                                    Floor Tile
                                                    Manufacturing.
                                327123...........  Other Structural Clay
                                                    Product
                                                    Manufacturing.
                                327124...........  Clay Refractory
                                                    Manufacturing.
                                327310...........  Cement Manufacturing.
                                327410...........  Lime Manufacturing
                                                    (Dolomite, Dead-
                                                    burned,
                                                    Manufacturing).
                                327420...........  Gypsum Product
                                                    Manufacturing.
                                327992...........  Ground or Treated
                                                    Mineral and Earth
                                                    Manufacturing.
                                331111...........  Steel Mills.
                                331511-513,        Various metal
                                 331521-522,        foundries (e.g.,
                                 331524-525, and    iron, steel,
                                 331528.            aluminum, and
                                                    copper)
Federal government............  .................  Not affected.
State/local/tribal government.  .................  Not affected.
------------------------------------------------------------------------
\1\ 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 regulated by this 
action. To determine whether your facility would be regulated by this 
action, you should examine the applicability criteria in 40 CFR 60.670 
(subpart OOO) or 40 CFR 60.730 (subpart UUU). If you have any questions 
regarding the applicability of this proposed action to a particular 
entity, contact the person listed in the preceding FOR FURTHER 
INFORMATION CONTACT section.

B. What should I consider as I prepare my comments to EPA?

    Do not submit information containing CBI to EPA through 
www.regulations.gov or e-mail. Send or deliver information identified 
as CBI only to the following address: Roberto Morales, OAQPS Document 
Control Officer (C404-02), Office of Air Quality Planning and 
Standards, Environmental Protection Agency, Research Triangle Park, NC 
27711, Attention: Docket ID No. EPA-HQ-OAR-2007-1018. 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

[[Page 21561]]

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. Where can I get a copy of this document?

    In addition to being available in the docket, an electronic copy of 
this proposed action is available on the Worldwide Web (WWW) through 
the Technology Transfer Network (TTN). Following signature, a copy of 
this proposed action will be posted on the TTN's policy and guidance 
page for newly proposed or promulgated rules at https://www.epa.gov/ttn/
oarpg. The TTN provides information and technology exchange in various 
areas of air pollution control.

D. When would a public hearing occur?

    If anyone contacts EPA requesting to speak at a public hearing by 
May 2, 2008, a public hearing will be held on May 7, 2008. Persons 
interested in presenting oral testimony or inquiring as to whether a 
public hearing is to be held should contact Mr. Bill Neuffer, listed in 
the FOR FURTHER INFORMATION CONTACT section, at least 2 days in advance 
of the hearing.

II. Background Information on Subpart OOO

A. What is the statutory authority for these proposed amendments to 
subpart OOO?

    New source performance standards (NSPS) implement Clean Air Act 
(CAA) section 111(b) and are issued for categories of sources which 
cause, or contribute significantly to, air pollution which may 
reasonably be anticipated to endanger public health or welfare. The 
primary purpose of the NSPS is to attain and maintain ambient air 
quality by ensuring that the best demonstrated emission control 
technologies are installed as the industrial infrastructure is 
modernized. Since 1970, the NSPS have been successful in achieving 
long-term emissions reductions in numerous industries by assuring cost-
effective controls are installed on new, reconstructed, or modified 
sources.
    Section 111 of the CAA requires that NSPS reflect the application 
of the best system of emission reductions which (taking into 
consideration the cost of achieving such emission reductions, any non-
air quality health and environmental impact and energy requirements) 
the Administrator determines has been adequately demonstrated. This 
level of control is commonly referred to as best demonstrated 
technology (BDT).
    Section 111(b)(1)(B) of the CAA requires EPA to periodically review 
and revise the standards of performance, as necessary, to reflect 
improvements in methods for reducing emissions.

B. What are the current NMPP NSPS?

    Standards of performance for NMPP (40 CFR part 60, subpart OOO) 
were promulgated in the Federal Register on August 1, 1985 (50 FR 
31328). The first review of the NMPP NSPS was completed on June 9, 1997 
(62 FR 31351).
    The NMPP NSPS applies to new, modified, and reconstructed affected 
facilities at plants that process any of the following 18 nonmetallic 
minerals: crushed and broken stone, sand and gravel, clay, rock salt, 
gypsum, sodium compounds, pumice, gilsonite, talc and pyrophyllite, 
boron, barite, fluorospar, feldspar, diatomite, perlite, vermiculite, 
mica, and kyanite. The affected facilities are each crusher, grinding 
mill, screening operation, bucket elevator, belt conveyor, bagging 
operation, storage bin, and enclosed truck or railcar loading station. 
Unless otherwise noted, the terms ``new'' or ``future'' as used in this 
preamble include modified or reconstructed units.

III. Summary of These Proposed Amendments to Subpart OOO

    The proposed amendments to subpart OOO of 40 CFR part 60 are 
summarized in Table 1 of this preamble.

                                 Table 1.--Summary of These Proposed Amendments
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Citation                      Change
-------------------------------------------------------
60.670(a  Exempt wet material processing operations;
  )(2)     clarify rule does not apply to plants with
           no crushers or grinding mills.
60.670(d  Revise to clarify that like-for-like
  )(1)     replacements that have no emissions increase
           are exempt from certain provisions.
60.670(f  Revise to conform with amended Table 1 to
     )     subpart OOO.
60.671    Add definitions of: Crush or crushing,
           saturated material, seasonal shut down, and
           wet material processing operations. Amend
           definition of ``screening operation'' to
           exempt static grizzlies.
60.672(a  Revise to reference Tables 2 and 3 to subpart
 ) and     OOO and to better match General Provisions
   (b)     language regarding compliance dates. Tables
           2 and 3 to subpart OOO contain revised
           emission limits and testing/monitoring
           requirements for future affected facilities.
60.672(c  Reserve because superseded by Table 3 to
     )     subpart OOO.
60.672(e  Revise cross-references. Replace Method 22
     )     (40 CFR part 60, Appendix A-7) no visible
           emissions limit for building openings with 7
           percent fugitive opacity limit.
60.672(f  Consolidate paragraphs to refer to Table 2 to
 ) and     subpart OOO. Specify exemption from stack PM
   (g)     concentration limit and that 7 percent
           opacity limit applies for future individual
           enclosed storage bins.
60.672(h  Remove 60.672(h) and reserve 60.675(h)
 ) and     because wet material processing exempted.
 60.675(
    h)
60.674    Renumber (a) and (b) as (a)(1) and (2). Add
           periodic inspections for future wet
           suppression systems and future baghouse
           monitoring requirements (Method 22 visible
           emission inspections or use of bag leak
           detection systems).
60.675    Add text to clarify that the required EPA
   and     test methods are located in Appendices A-1
 various   through A-7 of 40 CFR part 60 (formerly
 other     Appendix A of 60 CFR part 60).
 section
     s
 referen
  cing
  test
 methods
60.675(b  Cross reference exceptions to Method 5 (40
  )(1)     CFR part 60, Appendix A-3) or Method 17 (40
           CFR part 60, Appendix A-6).
60.675(c  Correct cross reference to amended paragraph
     )     in (c)(1).
          Expand (c)(2) into subparagraphs (i) and (ii)
           to reduce the duration of Method 9 (40 CFR
           part 60, Appendix A-4) stack opacity
           observations for storage bins or enclosed
           truck or railcar loading stations operating
           for less than 1 hour at a time.

[[Page 21562]]

 
          Revise (c)(3) and delete (c)(4) to make the
           fugitive Method 9 testing duration 30
           minutes and specify averaging time for all
           affected facilities.
60.675(d  Specify performance testing requirements for
     )     the building fugitive emission limit. Allow
           prior Method 22 tests showing compliance
           with the former no VE limit.
60.675(e  Add paragraph (e)(2) to allow Method 9
     )     readings to be conducted on three emission
           points at one time if specified criteria are
           met.
          Add paragraph (e)(3) to allow Method 5I (40
           CFR part 60, Appendix A-3) as an option for
           determining PM concentration from affected
           facilities that operate for less than 1 hour
           at a time.
          Add paragraph (e)(4) to address flow
           measurement from building vents with low
           exhaust gas velocity.
60.675(f  Correct cross references.
     )
60.675(g  Revise to reduce 30-day advance notification
     )     time for Method 9 fugitive performance test
           to 7 days.
60.675(i  Add section to state that initial performance
     )     test dates that fall during seasonal shut
           downs may be postponed no later than 60 days
           after resuming operation (with permitting
           authority approval).
60.676(b  Add requirement to previously reserved
     )     paragraph (b) for recording periodic
           inspections of water sprays and baghouse
           monitoring for future affected facilities.
60.676(d  Remove reference to upper limits on scrubber
     )     pressure and liquid flow rate.
60.676(f  Edit to conform to wet material processing
 ) and     exemption and/or relevant opacity limits.
   (g)
60.676(h  Delete reference to now reserved 60.7(a)(2).
     )     Waive requirement to submit 60.7(a)(1)
           notification of the date construction or
           reconstruction commenced.
60.676(k  Add section to state that notifications and
     )     reports need only be sent to the delegated
           authority (or the EPA Region when there is
           no delegated authority).
Table 1   Move to end of subpart OOO, shorten to
    to     include only exceptions to the General
 subpart   Provisions, and update comments.
   OOO
Table 2   Add table to specify the stack PM limits and
    to     testing/monitoring requirements for current
 subpart   and future affected facilities.
   OOO
Table 3   Add table to specify the fugitive opacity
    to     limits and testing/monitoring requirements
 subpart   for current and future affected facilities.
   OOO
----------------------------------------------------------------------------------------------------------------

IV. Rationale for These Proposed Amendments to Subpart OOO

A. How is EPA proposing to change the emission limits for future 
affected facilities?

    For ``future'' affected facilities constructed, modified, or 
reconstructed after today's date, we are proposing:
     To reduce the PM emission limits from 0.05 grams per dry 
standard cubic meter (g/dscm) (0.022 grains per dry standard cubic foot 
(gr/dscf)) to 0.02 g/dscm (0.014 gr/dscf) for affected facilities with 
capture systems (i.e., affected facilities that vent through stacks), 
and to eliminate the stack opacity limit for dry control devices; and
     To reduce the fugitive visible emission limits from 15 
percent to 12 percent for crushers, and from 10 percent to 7 percent 
for grinding mills, screening operations, bucket elevators, belt 
conveyors, bagging operations, storage bins, and enclosed truck or 
railcar loading stations.

The emission limits for affected facilities constructed, modified, or 
reconstructed before today's date remain unchanged.
    The 1985 promulgated NMPP NSPS are based on emission levels 
achieved using baghouse control or wet dust suppression techniques (see 
50 FR 31329, August 1, 1985). Both systems were determined to be BDT 
for reasons discussed in the preamble to the 1983 proposed rule (see 48 
FR 339569-39571, August 31, 1983). It was also noted in the 1983 
proposal preamble that certain wet scrubbers could perform comparably 
to BDT. As part of our review of subpart OOO, we collected information 
through site visits, trade associations, and state agencies. The 
information and comments these stakeholders provided us on the current 
NSPS are contained in the docket. We reviewed numerous NMPP permits to 
identify emissions limits more stringent than subpart OOO (and to 
understand if limits more stringent than subpart OOO are commonplace or 
rare) and emissions test data from a number of sources (trade 
associations and state agencies). A summary of state permits and 
emissions test data are in the docket. Our review of permits and other 
available information in the record did not reveal any new or emerging 
pollution prevention measures or particulate matter (PM) control 
technologies in the non-metallic minerals industries for consideration 
as BDT. Consistent with the prior BDT determination, the vast majority 
of subpart OOO affected facilities subject to stack emission limits 
have baghouse controls. A number of wet scrubber controls were observed 
as well. The subpart OOO fugitive emission limits are most commonly met 
through use of wet suppression (as needed), water carryover, or with a 
partial enclosure. Wet dust suppression remains the method of choice 
for the vast majority of crushed stone and sand & gravel facilities. 
These BDT control systems achieve a reduction in PM10 and 
PM2.5 along with reduction in larger PM particle sizes.
    The stack emissions data we reviewed included over 300 PM stack 
tests from 1990 and later for a variety of subpart OOO affected 
facilities and industries. A memorandum summarizing this test data is 
in the docket. Ninety-one percent of the PM stack test results achieved 
0.014 gr/dscf. Consistent with our prior BDT determination, the control 
technologies used for the affected facilities tested included primarily 
baghouses and wet scrubbers designed to meet subpart OOO. The high 
percentage of affected facilities currently able to meet 0.014 gr/dscf 
using either baghouses or wet scrubbers supports our conclusion that an 
emission limit of 0.014 gr/dscf can be achieved by well-maintained and 
operated control systems. Further, the available information suggests 
that establishing emission limits below 0.014 gr/dscf would result in a 
level of control that may be difficult for some NMPP control systems to 
achieve on a continuous basis.
    Some test results were above the limits under consideration but 
below the current NSPS limit of 0.022 gr/dscf. These units were 
considered as having marginal performance. The effect of reducing the 
stack PM limit would be to

[[Page 21563]]

ensure that the typical performance of BDT control systems today is 
achieved for future affected facilities and that controls with marginal 
performance are not installed in the future.
    Using the available information, we considered the incremental 
costs and emissions reductions for different levels of control to 
determine the appropriate stack emission limit representative of BDT 
for new, modified, and reconstructed affected facilities. The control 
systems that would be installed to meet the proposed limit of 0.014 
would be the same as those installed to meet the current NSPS limit of 
0.022 gr/dscf. Because there would be no change in control technology, 
we expect that the incremental costs would be very low or zero. 
However, limits below 0.014 gr/dscf may result in additional cost with 
little incremental emission reduction beyond that achieved by reducing 
the current limit (0.022 gr/dscf) to 0.014 gr/dscf. Therefore, we are 
proposing a PM limit of 0.014 gr/dscf as BDT for new, modified, and 
reconstructed affected facilities.
    The purpose of the current 7 percent stack opacity limit in subpart 
OOO is to provide inspectors and plant personnel a measure of ongoing 
compliance for dry control devices (namely baghouses). We are proposing 
to replace the 7 percent stack opacity limit with quarterly monitoring 
of baghouses for future affected facilities. The monitoring 
requirements for baghouses would occur at specified intervals (as 
discussed below) and ensure proper operation and maintenance of future 
baghouses on an ongoing basis. Therefore, a stack opacity limit would 
no longer be needed for future affected facilities.
    With respect to fugitive emissions, we looked at over 700 fugitive 
emissions test data points (maximum 6-minute opacity averages) for a 
variety of subpart OOO affected facilities and industries that do not 
vent through stacks. A memorandum summarizing this test data is in the 
docket. These data revealed that the vast majority of affected 
facilities perform better than the current fugitive emission limits of 
15 percent opacity for crushers and 10 percent opacity for other 
affected facilities. For crushers, 93 percent of the data points were 
at or below 12 percent opacity. Ninety-five percent of the data points 
for other types of affected facilities were at or below 7 percent 
opacity. Therefore, we are proposing revised fugitive emissions limits 
of 12 percent for crushers and 7 percent for all other affected 
facilities, which can be met by future affected facilities employing 
the same control measures as are used on today's affected facilities 
(e.g., wet suppression, water carryover, and/or partial enclosures). 
The emission reduction associated with lowering the fugitive opacity 
limit is not quantifiable based on available information. Because the 
same control measures needed to meet the current NSPS would be employed 
to meet the revised NSPS, there would be no incremental cost associated 
with this proposed reduction in the fugitive opacity limits. The effect 
of lowering the opacity limits would be to ensure that any wet 
suppression or enclosure systems with marginal performance (compared to 
the current NSPS) would no longer be acceptable for future affected 
facilities.
    Given the addition of revised limits to subpart OOO for affected 
facilities installed after today's date, we are proposing to revise 
Sec.  60.672 to include two tables that present the subpart OOO 
emission limits. The proposed Table 2 to subpart OOO would present the 
stack emission limits for affected facilities with capture systems. 
Capture systems are defined in subpart OOO as equipment (e.g., 
enclosures, ducts, etc.) used to capture and transport PM emissions to 
a control device. The proposed Table 3 to subpart OOO would present the 
fugitive emission limits for affected facilities without capture 
systems (i.e., affected facilities that do not vent through stacks). We 
request comment on whether these tables improve the readability of 
subpart OOO and help to distinguish between the stack and fugitive 
emission limits.
    Aside from the tables proposed to be added to subpart OOO, 
exemptions from selected emission limits would remain in the text of 
Sec.  60.672. A footnote to the proposed Table 2 would direct readers 
to Sec.  60.672 to review these exemptions. We are proposing to combine 
and revise former Sec.  60.672 paragraphs (f) and (g) into one 
paragraph Sec.  60.672(f) to clarify applicability of the PM emission 
limits to storage bins. Baghouses controlling individual enclosed 
storage bins are exempt from the stack PM concentration limit (but must 
meet the 7 percent stack opacity limit). However, baghouses controlling 
multiple storage bins are required to meet both the stack PM and 
opacity limits. We are retaining the 7 percent stack opacity limit for 
future baghouses controlling individual enclosed storage bins. In 
addition, we are also proposing to clarify in a footnote to Table 2 
that the subpart OOO opacity limits do not apply for affected 
facilities controlled by wet scrubbers. Wet scrubbers are required to 
monitor scrubber pressure loss and scrubber liquid flow rate instead of 
opacity. Therefore, no initial opacity test is required by subpart OOO 
for wet scrubbers.

B. How is EPA proposing to amend subpart OOO applicability and 
definitions?

    Wet material processing. We are proposing to add two definitions 
and to make other changes to exempt from subpart OOO wet material 
processing operations that have no potential for PM emissions. These 
types of operations were already exempted from the testing requirements 
of subpart OOO but remained subject to notification requirements and a 
no visible emissions (VE) limit (although no testing was required to 
demonstrate compliance with the no VE limit). Exempting wet material 
processing operations from this proposed rule altogether will reduce 
the burden associated with notifications and tracking of these 
operations as subpart OOO affected facilities with no requirements. We 
are proposing to define ``wet material processing operations'' 
similarly to how they were referred to before in subpart OOO. Wet 
material processing operations include: (a) Wet screening operations 
and subsequent screening operations, bucket elevators and belt 
conveyors in the production line that process saturated materials up to 
the first crusher, grinding mill or storage bin in the production line; 
or (b) screening operations, bucket elevators and belt conveyors in the 
production line downstream of wet mining operations that process 
saturated materials up to the first crusher, grinding mill or storage 
bin in the production line. Stakeholders have expressed concern that 
the term ``saturated'' is ambiguous and requested that we define that 
term. Therefore, we are also proposing to add a definition of 
``saturated material'' to subpart OOO to describe the type of material 
intended to be exempted from this proposed rule. Through the 
definitions of ``wet material processing operation'' and ``saturated 
material'' (as well as other existing definitions of ``wet mining 
operation'' and ``wet screening operation''), we intend to exempt from 
coverage under subpart OOO mineral material that is wet enough on its 
surface to remove the possibility of PM emissions being generated from 
processing of the material though screening operations, bucket 
elevators and belt conveyors. Material that is wetted solely by wet 
suppression systems designed to add surface moisture for dust control 
is not considered to be ``saturated material'' for purposes of this 
exemption. Examples of saturated material include slurries of water and 
mineral material, material that is wet as it enters the

[[Page 21564]]

processing plant from the mine, material that is wet from washing, 
material with a high percentage of moisture (considering mineral type), 
etc. This exemption for wet material processing operations is limited 
to screening operations, bucket elevators and belt conveyors (i.e., 
belt conveyor transfer points) because crushing or grinding of mineral 
material can expose new dry surfaces that pose a potential for PM 
emissions and other affected facilities (bagging operations, storage 
bins, and enclosed truck or railcar loading stations) usually process 
only dry material.
    Crushers. Industry representatives requested that we clarify the 
meaning of ``crusher'' and ``grinding mill'' by adding a definition of 
``crushing.'' The new definition of ``crushing'' would help to clarify 
that crushers and grinding mills do not include equipment that simply 
breaks up clumps of material (e.g., certain deagglomerators or 
shredders processing material that has become stuck together during 
processing) but does not further reduce the size of the material. The 
current definition of ``crusher'' employs the word ``crush'' and the 
current definition of grinding mill uses the word ``crushing.'' To 
capture both terms, we are proposing to add a new definition: ``Crush 
or crushing'' which means to reduce the size of nonmetallic mineral 
material by means of physical impaction of the crusher or grinding mill 
upon the material.
    Grizzlies. We are proposing to clarify that all grizzlies 
associated with truck dumping and static (non-agitating) grizzlies are 
not subpart OOO affected sources. Grizzlies can sometimes be confused 
with screening operations because they are used to separate larger 
material from smaller material. Grizzlies range from simple metal 
grates to equipment that agitates or vibrates material similarly to 
screening operations. Grizzlies are often associated with truck 
dumping, where a truck dumps material from the mine into the grizzly 
feeder. The grizzly feeder separates fines and smaller pieces of rock 
from larger material (e.g., boulders) that require initial crushing. 
Grizzly feeders associated with truck dumping are not subject to 
subpart OOO because Sec.  60.672(d) states that, ``Truck dumping of 
nonmetallic minerals into any screening operation, feed hopper, or 
crusher is exempt from the requirements of this section.'' However, 
applicability of subpart OOO to grizzlies used elsewhere in NMPP has 
been less clear. Certain types of grizzlies (specifically metal grate 
grizzlies that do not mechanically agitate or vibrate the mineral 
material) are clearly different from screening operations. Therefore, 
we are proposing to amend the definition of screening operation to 
state that ``Grizzly feeders associated with truck dumping and static 
(non-moving) grizzlies used anywhere in the nonmetallic mineral 
processing plant are not considered to be screening operations.''

C. How is EPA proposing to amend the testing requirements?

    Repeat testing for future affected facilities. Subpart OOO 
currently requires NMPP to conduct an initial performance test to 
demonstrate compliance with the relevant stack or fugitive emission 
limits. Stack PM emissions are to be measured with EPA Method 5 (40 CFR 
part 60, Appendix A-3) or Method 17 (40 CFR part 60, Appendix A-6) and 
stack opacity must be measured with EPA Method 9 (40 CFR part 60, 
Appendix A-4). The opacity from affected facilities not venting through 
stacks must be measured with EPA Method 9 (though the duration of 
Method 9 readings is reduced in some cases as discussed below). Repeat 
performance tests currently are not required by subpart OOO, but may be 
required by permitting authorities for some NMPP. As part of an ongoing 
effort to improve compliance with various Federal air emission 
regulations, we are proposing to require repeat performance testing 
once every 5 years for future subpart OOO affected facilities that do 
not have ongoing monitoring requirements. Specifically, a repeat Method 
9 test is proposed to be required for future affected facility fugitive 
emissions controlled by water carryover or other means. Repeat Method 9 
tests are not being proposed for fugitive affected facilities with wet 
suppression water sprays because, (as discussed below) periodic 
inspections of the water spray nozzles are being proposed for these 
emission points.
    The proposed repeat testing requirements appear in the proposed 
Table 3 to subpart OOO. We considered annual repeat testing and repeat 
testing every 5 years for stacks, but concluded that this would be 
overly burdensome given the number of affected facilities (including 
numerous small stacks) to be tested at NMPP. As discussed later, we are 
proposing ongoing monitoring requirements for future affected 
facilities that do not have repeat testing requirements to ensure that 
future control systems are properly operated and maintained over their 
useful life.
    Fugitive Method 9 test duration. Subpart OOO currently requires 
initial Method 9 observations for affected facilities with fugitive 
emissions. As currently written, the duration of the Method 9 
observations may be reduced from 3 hours to 1 hour if there are no 
individual readings greater than the applicable limit and if there are 
no more than three readings at the applicable limit during the 1-hour 
period. Stakeholders have expressed concern regarding the amount of 
time required to complete the initial Method 9 tests given the number 
of affected facilities at NMPP that require readings (e.g., numerous 
conveyor transfer points throughout the NMPP). The stakeholders also 
noted that in many cases the readings being recorded are all zeros. We 
have considered the Method 9 observation time in the context of the 
numerous fugitive affected facilities that require observations at NMPP 
and the other changes to testing requirements we are proposing today 
(i.e., addition of repeat testing requirements). We are proposing three 
amendments to the fugitive Method 9 testing provisions for all affected 
facilities to reduce the amount of time required for testing without 
sacrificing enforceability of the rule or air quality. First, we are 
removing the stipulations that could trigger a 3-hour test. Second, we 
are proposing to require a 30-minute fugitive Method 9 test duration 
(five 6-minute averages) for all affected facilities. Compliance with 
the applicable fugitive emissions limit would be based on the average 
of the five 6-minute averages recorded during the 30 minutes. Third, 
considering the number of affected facilities to be tested and the 
close proximity of some of these affected facilities to one another at 
NMPP plants, we are proposing to allow a single visible emission 
observer to conduct observations for up to three subpart OOO emission 
points at a time (including stack and vent emission points) provided 
that certain criteria are met (as proposed in Sec.  60.675(e)(2)).
    Storage bins and loading stations operating less than 1 hour at a 
time. Based on comments from stakeholders and our own review of 
emission test reports, we recognize that affected facilities such as 
storage bins (including silos) and loading stations may operate 
intermittently such that emissions testing for three 1 hour periods can 
be impractical in some instances. For example, storage bins may be 
filled for a time period of less than an hour and then filling stops 
for some time. Likewise, loading operations may operate for a short 
time and then cease operation. Some facilities have addressed these 
challenges during testing by filling and then emptying a

[[Page 21565]]

storage bin, only to re-route the same material back into the bin. To 
provide some relief from this situation, we are proposing to add EPA 
Method 5I (40 CFR part 60, Appendix A-3)--``Determination of Low Level 
Particulate Matter Emissions from Stationary Sources'' to subpart OOO 
as an optional test method that can be used instead of Methods 5 or 17. 
Method 5I is useful for low PM concentration applications, where the 
total PM catch is 50 milligrams or less. With Method 5I, the sample 
rate and total gas volume is adjusted based on the estimated grain 
loading of the emission point and the total sampling time is a function 
of the estimated mass of PM to be collected for the run. Thus, Method 
5I can be used in situations where the minimum sampling volume of 60 
dscf (required for Methods 5 and 17) cannot be obtained (e.g., for 
affected facilities that operate for less than 1 hour at a time). We 
are also proposing to reduce the Method 9 stack opacity test duration 
from 3 hours to the duration that the affected facility operates (but 
not less than 30 minutes) for baghouses that control storage bins or 
enclosed truck or railcar loading stations that operate for less than 1 
hour at a time.
    Buildings. Subpart OOO contains an optional compliance method for 
affected facilities inside of buildings. Rather than measuring the 
emissions from each affected facility within a building (which is 
sometimes difficult due to close equipment spacing and lighting), NMPP 
can opt to measure emissions from the building. Subpart OOO currently 
requires buildings to meet a zero VE limit (measured with EPA Method 
22), and additionally requires the building vents to meet the stack PM 
concentration and opacity limits. During the NSPS review, stakeholders 
requested changes to the optional emission limits and testing 
procedures for buildings. Some stakeholders pointed out that noise 
barriers are very similar to buildings in that they enclose affected 
facilities and reduce or prevent fugitive emissions. We agree. Subpart 
OOO defines ``building'' as ``any frame structure with a roof.'' 
According to the definition of building, noise barriers resembling 
buildings with a roof would be considered as buildings. Stakeholders 
also requested that buildings housing affected facilities be subject to 
the same emission limits as the affected facilities in the buildings. 
The stakeholders believe that, as written now, subpart OOO is more 
stringent for affected facilities inside of buildings than for those 
located outside. Last, stakeholders noted difficulties with performing 
Method 5 emissions testing on building vents because building vents 
often have no stacks and/or low gas flow rates that are insufficient to 
meet isokinetic measurement requirements.
    We have reviewed the current provisions relating to buildings and 
are proposing to apply a fugitive emission limit of 7 percent opacity 
(measured with EPA Method 9) at the inlet and outlet of buildings (or 
at other building openings except powered vents). Compliance with the 7 
percent opacity limit would be demonstrated through initial testing. A 
repeat opacity test would be required (within 5 years from the previous 
test) for buildings housing any future affected facility. Buildings 
that demonstrated compliance with the Method 22 no VE limit through 
performance testing would not be required to be retested to show 
compliance with today's proposed Method 9 opacity limit unless a future 
affected facility is installed in the building. The applicable stack 
emission limits and testing/monitoring requirements from the proposed 
Table 2 to subpart OOO would continue to apply to powered building 
vents. We are proposing to add Sec.  60.675(e) to provide an 
alternative procedure for determining building vent flow rate for 
building vents with flow too low to measure. We believe these changes 
will simplify the methodology used to demonstrate compliance with 
subpart OOO for buildings while ensuring that PM emissions from 
affected facilities remain adequately controlled.
    Seasonal shut downs. Stakeholders representing the construction 
aggregate (i.e., crushed stone and construction sand and gravel) sector 
indicated that the initial performance test dates sometimes fall during 
seasonal plant closures. Consistent with the NSPS General Provisions, 
initial performance tests are required 60 calendar days after achieving 
maximum production but no later than 180 calendar days after initial 
startup of an affected facility. The stakeholders noted that aggregate 
plants often cease production during winter months when demand for 
construction aggregate is low. The current initial performance test 
dates based on calendar days can fall during these periods of seasonal 
shut down. Therefore, we are proposing to add Sec.  60.675(j) to 
subpart OOO to allow plants to postpone initial performance testing 
until 60 calendar days after resuming operation following a seasonal 
shut down of an affected facility. Approval from the permitting 
authority would be required for postponing the initial compliance test 
(e.g., there should be some form of communication with the permitting 
authority to indicate the duration of the seasonal shut down of the 
affected facility) and to specify the revised deadline for the 
performance test. We consider a seasonal shut down to be at least 45 
consecutive days of shut down of the affected facility and are 
proposing a definition to that effect. We are limiting the proposed 
postponing of performance tests to initial performance tests because 
repeat performance tests can be scheduled at a time the NMPP chooses 
within 5 years of the prior performance test.

D. How is EPA proposing to amend the monitoring requirements?

    Monitoring for fugitive emissions limits. Fugitive emissions from 
subpart OOO affected facilities are often controlled by wet 
suppression. In wet suppression systems, water (and surfactant) is 
sprayed on nonmetallic minerals at various locations in the process 
line but not necessarily at every affected facility. Carryover of water 
sprayed at affected facilities upstream in the process line is often 
sufficient to control fugitive emissions from affected facilities 
downstream in the process. Partial enclosures or other means may also 
be used to reduce fugitive emissions in addition to water sprays or 
water carryover. We are proposing separate requirements to demonstrate 
ongoing compliance with the fugitive emission limits for future 
affected facilities where water is sprayed and for other future 
affected facilities (i.e., those controlled by water carryover or other 
means). As mentioned above, we are proposing a repeat Method 9 test 
(within 5 years from the previous performance test) for future affected 
facility fugitive emissions controlled by water carryover or other 
means. A repeat Method 9 test is not being proposed for fugitive 
affected facilities with water sprays. Instead we are proposing monthly 
periodic inspections of water sprays to ensure that water is flowing to 
the discharge water spray nozzles in the wet suppression system. If, 
during an inspection, you find that water is not flowing properly then 
you would be required to initiate corrective action within 24 hours. We 
are proposing the periodic inspections of water sprays as part of our 
ongoing effort to improve compliance with Federal air emission 
regulations such as subpart OOO. We believe that monthly inspections 
would ensure that subpart OOO wet suppression systems remain in good 
working order and provide the required control of fugitive emissions.
    Baghouse monitoring. As mentioned previously, we are replacing the 
7

[[Page 21566]]

percent stack opacity limit with ongoing monitoring for future 
baghouses. We believe the monitoring requirements of this proposed rule 
would be more effective in ensuring ongoing compliance with the PM 
limit than the current stack opacity limit (which has no associated 
repeat testing requirements) because this proposed monitoring would 
occur at regular intervals.
    We are proposing two options for monitoring of future baghouses: 
(1) Quarterly visible emissions inspections, or (2) use of a bag leak 
detection system. The quarterly visible emissions inspections would be 
conducted using EPA Method 22 for 30 minutes. The visible emissions 
inspections would be successful if no visible emissions are observed. 
If any visible emissions are observed, then you would be required to 
initiate corrective action within 24 hours to restore the baghouse to 
normal operation. We believe it is unlikely, but if your baghouse 
normally displays some visible emissions, then you would be allowed to 
establish a different baghouse-specific success level for the visible 
emissions inspections (other than no visible emissions) by conducting a 
PM test simultaneously with a Method 22 test to determine what 
constitutes normal visible emissions from your baghouse when it is in 
compliance with the subpart OOO PM concentration limit. The revised 
visible emissions success level must be incorporated into your permit.
    We are proposing to allow use of a bag leak detection system as an 
alternative to the periodic Method 22 visible emission inspections for 
baghouses controlling future affected facilities. The bag leak 
detection system must be installed and operated according to the 
proposed Sec.  60.674(d).
    Wet scrubber monitoring. Stakeholders requested that we remove the 
upper limits for wet scrubber operating parameters (pressure drop and 
liquid flow) referred to in Sec.  60.676(d). Increases in these 
parameters would only increase scrubber PM removal efficiency. 
Therefore, we are proposing to revise Sec.  60.676(d) to delete 
reference to scrubber pressure gain and the upper limit for scrubber 
liquid flow.
    We are not proposing any further changes to the wet scrubber 
monitoring requirements at this time. However, the Agency is drafting 
Performance Specification 17 (PS-17) and Procedure 4 for continuous 
parameter monitoring systems (which include pressure and liquid flow 
measurements). Following proposal and public comment of PS-17 and 
Procedure 4, the procedures and requirements in PS-17 and Procedure 4 
would supersede the wet scrubber monitoring language in subpart OOO for 
affected facilities with wet scrubbers installed after the proposal 
date of PS-17 and Procedure 4.

E. How is EPA proposing to amend the notification, reporting, and 
recordkeeping requirements?

    Notifications and reports. We are proposing to simplify the 
notification requirements in subpart OOO in several ways. There are 
thousands of NMPP dispersed throughout the U.S. Given the number of 
affected facilities at each NMPP (e.g., individual crushers, screens, 
belt conveyor transfer points, etc.), notifications relating to every 
new affected facility result in volumes of paperwork for both NMPP and 
regulatory agencies. We believe these proposed changes to the 
notification requirements in subpart OOO would reduce the paperwork 
required for the numerous affected NMPP and regulatory personnel 
without sacrificing air quality.
    First, Sec.  60.676(h) of subpart OOO waived the former requirement 
in Sec.  60.7(a)(2) of subpart A for notification of the anticipated 
date of initial startup. Section 60.7(a)(2) was reserved in a 1999 
amendment to subpart A to reduce paperwork burden. We are proposing to 
delete reference to Sec.  60.7(a)(2) in Sec.  60.676(h) to be 
consistent with subpart A. We are also proposing new rule language for 
Sec.  60.676(h) to waive the Sec.  60.7(a)(1) (subpart A) requirement 
to submit a notification of commencement of construction/reconstruction 
for NMPP affected facilities. Non-metallic mineral processing plants 
are already required under State or Federal permit programs to obtain 
permits to construct and/or operate. In efforts to streamline the 
permitting process, many States have set up general permits for NMPP 
(e.g., crushed stone facilities) due to the large number of these 
facilities in most States. We believe the purpose of the Sec.  
60.7(a)(1) notification of commencement of construction/reconstruction 
for NMPP can be adequately served through the NMPP permitting process 
and the Sec.  60.7(a)(3) (subpart A) notification of the actual date of 
initial startup. The Sec.  60.7(a)(3) notification is needed and has 
been retained in subpart OOO because it is tied directly to the initial 
performance test date.
    Second, due to the large number of affected facilities and 
associated notifications and reports, we are proposing to add a new 
Sec.  60.676(k) to subpart OOO stating that notifications generated 
under subpart OOO are only to be sent to either the State (if the State 
is delegated authority to administer NSPS) or to the EPA Region (if the 
State has not been delegated authority), but not to both the State and 
EPA Region.
    Third, we are proposing in Sec.  60.675(g) to change the 30-day 
advance notification deadline (required in Sec.  60.7(a)(6)) for 
performance tests involving only Method 9 to a 7-day advance 
notification. We are proposing this change because of the large number 
of NMPP that are required to conduct only Method 9 testing for fugitive 
emissions from affected facilities, because plans for NMPP Method 9 
opacity readings require little review (if any), and because Method 9 
tests are affected by weather (visibility) and subject to rescheduling 
such that a 30-day advanced notification can be impractical for NMPP. 
We are also proposing to remove the language in Sec.  60.675(g) which 
specified when plants are to notify the Administrator of rescheduled 
test dates because the same language now appears in Sec.  60.8(d) of 
subpart A following an amendment to Sec.  60.8(d) promulgated in 1999.
    Recordkeeping for future affected facilities. We are proposing to 
require NMPP to keep records of periodic inspections performed on water 
sprays (monthly checks that water is flowing) or baghouses (quarterly 
Method 22 readings) controlling future affected facilities. Each 
periodic inspection would be required to be recorded in a logbook which 
may be maintained in written or electronic format. The logbook entries 
would include inspection dates and any corrective actions taken. The 
logbook would be kept onsite and made available to the EPA or delegated 
authority upon request. Plants opting to use bag leak detection systems 
in lieu of periodic visible emissions inspections for baghouses would 
be required to keep the records specified in the proposed Sec.  
60.676(b)(2). According to Sec.  60.7(f), records are required to be 
retained for a period of two years.

V. Modification and Reconstruction Provisions

    Existing affected facilities that are modified or reconstructed 
would be subject to these proposed amendments for future affected 
facilities. Under CAA section 111(a)(4), ``modification'' means any 
physical change in, or change in the method of operation of, a 
stationary source which increases the amount of any air pollutant 
emitted by such source or which results in the emission of any air 
pollutant not previously emitted. Changes to an existing facility that 
do not result in an increase in emissions are not considered 
modifications.

[[Page 21567]]

    Rebuilt affected facilities would become subject to the proposed 
standards under the reconstruction provisions, regardless of changes in 
emission rate. Reconstruction means the replacement of components of an 
existing facility such that (1) the fixed capital cost of the new 
components exceeds 50 percent of the fixed capital cost that would be 
required to construct a comparable entirely new facility; and (2) it is 
technologically and economically feasible to meet the applicable 
standards (40 CFR 60.15).

VI. Clarifications on Subpart OOO

    Today we are clarifying some common questions about the 
applicability of subpart OOO to synthetic gypsum, sodium carbonate, 
lime, and activated carbon. Synthetic gypsum is a by-product of flue 
gas desulfurization (FGD). Synthetic gypsum has the same chemical 
composition as natural gypsum and is used in many of the same products 
as natural gypsum (e.g., gypsum wallboard). We have concluded in prior 
applicability determinations, and wish to clarify today, that synthetic 
gypsum is considered to be a ``nonmetallic mineral'' as defined in 
subpart OOO and plants that crush or grind synthetic gypsum meet the 
subpart OOO definition of ``nonmetallic mineral processing plant.'' 
Electric utilities operating FGD systems use limestone or lime in the 
FGD systems to capture sulfur dioxide emissions and convert the mineral 
material into synthetic gypsum. Some utilities may use sodium carbonate 
as an additive in FGD systems. Limestone and sodium carbonate are 
included in the subpart OOO definition of ``nonmetallic mineral.'' 
Lime, however, is not included in the definition of ``nonmetallic 
mineral'' because processing of lime (which is manufactured by the high 
temperature calcination of limestone) is subject to a separate NSPS 
(NSPS subpart HH for Lime Manufacturing). Therefore, we wish to clarify 
that crushing or grinding of lime does not subject plants to subpart 
OOO. However, electric utilities (or other types of plants) that crush 
or grind limestone or sodium carbonate meet the subpart OOO definition 
of ``nonmetallic mineral processing plant.'' Electric utilities (or 
other types of plants) that handle, but do not crush or grind, the 
nonmetallic minerals limestone, sodium carbonate, or synthetic gypsum 
do not meet the definition of ``nonmetallic mineral processing plant.''
    Activated carbon is also used by some utilities for emissions 
control applications. Activated carbon is not included in the 
definition of ``nonmetallic mineral'' under subpart OOO. Thus, we are 
clarifying that processing of activated carbon is not subject to 
subpart OOO.

VII. Summary of Cost, Environmental, Energy, and Economic Impacts of 
Proposed Amendments to Subpart OOO

    In setting standards, the CAA requires us to consider alternative 
emission control approaches, taking into account the estimated costs as 
well as impacts on energy, solid waste, and other effects. We request 
comment on whether we have identified the appropriate alternatives and 
whether these proposed standards adequately take into consideration the 
incremental effects in terms of emission reductions, energy, and other 
effects of these alternatives. We will consider the available 
information in developing the final rule.

A. What are the impacts for NMPP?

    We are presenting estimates of the impacts for these proposed 
amendments to 40 CFR part 60, subpart OOO that change the performance 
standards. The cost, environmental, and economic impacts presented in 
this section are expressed as incremental differences between the 
impacts of NMPP complying with the proposed subpart OOO revisions and 
the current NSPS requirements of subpart OOO (i.e., baseline). The 
impacts are presented for future NMPP affected facilities that commence 
construction, reconstruction, or modification over the 5 years 
following promulgation of the revised NSPS. The analyses and the 
documents referenced below can be found in Docket ID No. EPA-HQ-OAR-
2007-1018.
    In order to determine the incremental impacts of this proposed 
rule, we first estimated that 332 new NMPP would comply with subpart 
OOO in the 5 years following promulgation. For further detail on the 
methodology of these calculations, see Docket ID No. EPA-HQ-OAR-2007-
1018.
    The proposed revisions to the subpart OOO emission limits for 
future affected facilities do not reflect use of any new or different 
control technologies, but are an adjustment of the limits to better 
reflect the performance of current (baseline) control technologies. 
There is no difference in the control systems used to meet baseline and 
those that would be used to meet these proposed revised emission limits 
for future affected facilities. Therefore, there would be no difference 
in control costs, water or solid waste impacts, or actual emission 
reductions achieved as a result of these proposed revisions to the 
emission limits for future affected facilities. As stated previously, 
the effect of reducing the emission limits would be to ensure that the 
typical performance of today's control systems is achieved for future 
affected facilities and that controls with marginal performance are not 
installed in the future. The potential nationwide emission reduction 
(the nationwide emission reduction associated with lowering the PM 
limit from 0.022 to 0.014 gr/dscf) could be as much as 120 megagrams 
per year (Mg/yr) (130 tpy) PM. These potential emission reductions are 
overestimated because the majority of control systems installed on 
future affected facilities would likely have resulted in emissions at 
or below the proposed emission limits even in the absence of these 
proposed revisions.
    Unlike for control costs and emissions reductions, there are 
differences in notification, testing, monitoring, reporting, and 
recordkeeping (MRR) costs between baseline and these proposed revisions 
to subpart OOO. We are proposing some amendments to subpart OOO that 
would reduce costs and other amendments that would in