[Federal Register Volume 79, Number 131 (Wednesday, July 9, 2014)]
[Proposed Rules]
[Pages 39241-39265]
[FR Doc No: 2014-15868]

Vol. 79

Wednesday,

No. 131

July 9, 2014

Part V

Environmental Protection Agency

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40 CFR Part 60

 Standards of Performance for Grain Elevators; Proposed Rule

Federal Register / Vol. 79 , No. 131 / Wednesday, July 9, 2014 /
Proposed Rules

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 60

[EPA-HQ-OAR-2010-0706; FRL-9912-76-OAR]
RIN 2060-AP06

Standards of Performance for Grain Elevators

AGENCY: Environmental Protection Agency.

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) is proposing
amendments to the Standards of Performance for Grain Elevators as a
result of the 8-year review of the new source performance standards
required by the Clean Air Act. We are proposing to clarify certain
provisions in the existing subpart DD. The EPA is also proposing a new
subpart DDa for grain elevators, which would apply to affected
facilities that commence construction, modification or reconstruction
after July 9, 2014 and includes the proposed clarifications for subpart
DD and several new provisions. In response to Executive Order 13563,
Improving Regulation and Regulatory Review, the EPA conducted an
analysis of subpart DD. In considering the directives of the Executive
Order, the EPA conducted several analyses to determine the
effectiveness of subpart DD, to determine whether subpart DD is still
relevant, and to determine whether subpart DD is excessively
burdensome. Based on the results of these analyses, the EPA concluded
that subpart DD is still effective, relevant and not excessively
burdensome.

DATES: Comments. Comments must be received on or before October 7,
2014. Under the Paperwork Reduction Act, comments on the information
collection provisions are best assured of having full effect if the
Office of Management and Budget receives a copy of your comments on or
before August 8, 2014.
    Public Hearing. The EPA will hold a public hearing on this proposed
rule if requested. Requests for a hearing must be made by July 24,
2014. Contact Ms. Virginia Hunt via email<EMAIL_ADDRESS>or
phone<PHONE_NUMBER>) by July 24, 2014 to request a public hearing. If a
hearing is requested, the EPA will announce the details, including
specific dates, times, addresses and contact information for the
hearing, in a separate Federal Register notice.

ADDRESSES: Submit your comments, identified by Docket ID Number EPA-HQ-
OAR-2010-0706, by one of the following methods:
    Federal eRulemaking Portal: http://www.regulations.gov: Follow the
online instructions for submitting comments.
    Email<EMAIL_ADDRESS>Include docket ID Number EPA-HQ-OAR-
2010-0706 in the subject line of the message.
    Fax:<PHONE_NUMBER>, Attention Docket ID Number EPA-HQ-OAR-2010-
0706.
    Mail: Environmental Protection Agency, EPA Docket Center (EPA/DC),
Mail Code 28221T, Attention Docket ID Number EPA-HQ-OAR-2010-0706, 1200
Pennsylvania Avenue 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 Street NW., Washington, DC 20503.
    Hand/Courier Delivery: EPA Docket Center, Room 3334, EPA WJC West
Building, 1301 Constitution Ave. NW., Washington, DC 20004, Attention
Docket ID Number EPA-HQ-OAR-2010-0706. 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 Number EPA-HQ-OAR-
2010-0706. 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 http://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 http://www.regulations.gov or email. Send or deliver
information identified as CBI to only the mail or hand/courier delivery
address listed above, attention: Docket ID Number EPA-HQ-OAR-2010-0706.
The http://www.regulations.gov Web site is an ``anonymous access''
system, which means the EPA will not know your identity or contact
information unless you provide it in the body of your comment. If you
send an email comment directly to the EPA without going through http://www.regulations.gov, your email 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, the 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 the EPA cannot read your comment due to technical
difficulties and cannot contact you for clarification, the EPA may not
be able to consider your comment. Electronic files should avoid the use
of special characters, any form of encryption and be free of any
defects or viruses. For additional information about the EPA's public
docket, visit the EPA Docket Center homepage at: http://www.epa.gov/dockets.
    Docket. The docket number for the proposed amendments to the grain
elevator new source performance standards (40 CFR part 60, subparts DD
and DDa) is Docket ID Number EPA-HQ-OAR-2010-0706. All documents in the
docket are listed in the http://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 http://www.regulations.gov or in
hard copy at the Air Docket, EPA/DC, EPA West, Room 3334, 1301
Constitution Ave. NW., Washington, DC. The EPA docket facility 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 Docket is (202) 566-
1742.

FOR FURTHER INFORMATION CONTACT: For information concerning the
proposed amendments, contact Mr. Bill Schrock, Natural Resources Group,
Sector Policies and Programs Division (E143-03), Research Triangle
Park, North Carolina 27711; telephone number<PHONE_NUMBER>; fax number
(919) 541-3470; email address<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION:
    World Wide Web. In addition to being available in the docket, an
electronic copy of the proposed amendments is available on the
Technology Transfer Network (TTN) Web site. Following signature, the
EPA will post a copy of the amendments at http://www.epa.gov/ttn/atw/eparules.html. The TTN provides information and technology exchange in
various areas of air pollution control.
    Acronyms and Abbreviations. The following acronyms and
abbreviations are used in this document:

ANSI American National Standards Institute
ASTM American Society for Testing and Materials
BACT Best available control technology
BDT Best demonstrated technology
BLDS Bag leak detection systems
BSER Best system of emission reduction
CAA Clean Air Act
CBI Confidential business information
CEDRI Compliance and Emissions Data Reporting Interface
CFR Code of Federal Regulation
CDX Central Data Exchange
EJ Environmental justice
ERT Electronic Reporting Tool
FSA Farm Service Agency
g/dscm Grams per dry standard cubic meter
gr/dscf Grains per dry standard cubic foot
gr/dscfm Grains per dry standard cubic foot per minute
HAP Hazardous air pollutants
ICR Information Collection Request
kg Kilogram
LAER Lowest achievable emission rate
mg Milligram
mm Millimeter
NAICS North American Industry Classification System
NSPS New source performance standard
NTTAA National Technology Transfer and Advancement Act
OECA Office of Enforcement and Compliance Assurance
OMB Office of Management and Budget
PM Particulate matter
RACT Reasonably available control technology
RBLC RACT/BACT/LAER Clearinghouse
RFA Regulatory Flexibility Act
SBA Small Business Administration
SBREFA Small Business Regulatory Enforcement Fairness Act
SISNOSE Significant Economic Impact on a Substantial Number of Small
Entities
SSM Startup, shutdown and malfunction
TSF Temporary storage facility
tpy Tons per year
TTN Technology Transfer Network
UMRA Unfunded Mandates Reform Act
USDA United States Department of Agriculture
VCS Voluntary consensus standards

    Organization of This Document. The following outline is provided to
aid in locating information in this preamble.

I. Executive Summary
    A. Purpose of Regulatory Action
    B. Summary of Major Amendments
    C. Summary of Costs and Benefits
II. General Information
    A. Does this action apply to me?
    B. What should I consider as I prepare my comments?
III. Background Information
    A. What is the statutory authority for these proposed revisions?
    B. What is the regulatory history for grain elevators?
IV. Summary of Proposed Amendments
    A. What source category is being regulated?
    B. What pollutants are emitted from these sources?
    C. What are the proposed standards?
V. Rationale for Proposed Amendments
    A. How did the EPA conduct the BSER analysis?
    B. How did the EPA evaluate changes to the methodology for
determining applicability of the grain elevator NSPS?
    C. How did the EPA evaluate the compliance requirements in the
grain elevator NSPS?
    D. How did the EPA evaluate additional changes for the grain
elevator NSPS?
VI. Summary of Cost, Environmental, Energy and Economic Impacts of
These Proposed Standards
    A. What are the impacts for subpart DDa?
    B. What are the secondary impacts for subpart DDa?
    C. What are the economic impacts for subpart DDa?
VII. Other Considerations
    Executive Order 13563: Improving Regulation and Regulatory
Review
VIII. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review and
Executive Order 13563: Improving Regulation and Regulatory 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 That Significantly Affect
Energy Supply, Distribution or Use
    I. National Technology Transfer and Advancement Act
    J. Executive Order 12898: Federal Actions To Address
Environmental Justice in Minority Populations and Low-Income
Populations

    A redline version of the regulatory language that incorporates the
proposed changes in this action is available in the docket for this
action (Docket ID No. EPA-HQ-OAR-2010-0706)

I. Executive Summary

A. Purpose of Regulatory Action

    New source performance standards implement CAA section 111(b) and
are issued for categories of sources that EPA has listed because they
cause, or contribute significantly to, air pollution, that 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 application of the best system of emission
reduction (BSER) that has been adequately demonstrated, taking into
consideration the cost of achieving such emission reductions, and any
non-air quality health and environmental impact and energy
requirements. Section 111(b)(1)(B) of the CAA requires the EPA to
review and, if appropriate, revise existing NSPS at least every 8
years. The NSPS for grain elevators (40 CFR part 60, subpart DD) were
promulgated in 1978 and last reviewed in 1984. As part of the review,
the EPA is required to consider what degree of emission limitation is
achievable through the application of the BSER, which (taking into
account the cost of achieving such reduction and any nonair quality
health and environmental impact and energy requirements) the
Administrator determines has been adequately demonstrated. The EPA also
considers the emission limitations and reductions that have been
achieved in practice.
    In addition to conducting the NSPS review, the EPA is evaluating
the start-up, shutdown and malfunction (SSM) provisions in the rule in
light of the D.C. Circuit Court of Appeals decision in Sierra Club v.
EPA, 551 F.3d 1019 (D.C. Cir. 2008), which held that the SSM exemption
in the General Provisions in 40 CFR part 63 violated the CAA's
requirement that some standards apply continuously. In the Sierra Club
case, the D.C. Circuit vacated the SSM exemption provisions in the
General Provisions of 40 CFR part 63 for non-opacity and opacity
standards. The court explained that under section 302(k) of the CAA,
emissions standards or limitations must be continuous in nature. The
court then held that the SSM exemption violates the CAA's requirement
that some section 112 standards apply continuously. In light of the
court's reasoning, all rule provisions must be carefully examined to
determine whether they provide for periods when no emission standard
applies. The EPA believes that even though the Court in Sierra Club v.
EPA was considering a challenge to a section 112 NESHAP standard, the
Court's reasoning applies equally to CAA section 111 (NSPS) and section
129 rules. The EPA's general approach to SSM periods has been used
consistently in CAA section 111, section 112 and section 129 rulemaking
actions, since the D.C. Circuit's decision in Sierra Club. See, e.g.,
New Source Performance Standards Review for Nitric Acid Plants, Final
Rule, 77 FR 48433 (August 14, 2012); New Source Performance Standards
for New Stationary Sources and Emission Guidelines for Existing
Sources; Commercial and Industrial Solid Waste Incineration Units,
Final rule, 76 FR 15704 (March 21, 2011); Oil and Natural Gas Sector:
New Source Performance Standards and National Emission Standards for
Hazardous Air Pollutants Reviews; Final rules, 77 FR 49490 (August 16,
2012).
    To address the NSPS review, SSM exemptions and other changes, the
EPA

is proposing a new subpart DDa for grain elevators, which would apply
to affected facilities that commence construction, modification or
reconstruction after July 9, 2014. The affected facilities at grain
elevators under the existing subpart DD and the proposed subpart DDa
are each new, modified or reconstructed truck unloading station, truck
loading station, barge and ship unloading station, barge and ship
loading station, railcar loading station, railcar unloading station,
grain dryer and all grain handling operations. The EPA is also
proposing amendments to subpart DD that will apply to facilities
subject to DD to clarify certain definitions and provisions. The EPA is
also proposing testing, monitoring, recordkeeping and reporting
requirements for subpart DDa that are in some ways different from what
is required under subpart DD. Where feasible, the EPA considered ways
to reduce the testing, monitoring, recordkeeping, and reporting burden,
while making the proposed requirements less ambiguous and more
straightforward for determining compliance. The proposed subpart DDa
requirements reflect what well-controlled sources are doing within the
grain elevator industry since the last review in 1984.
    This rulemaking also responds to Executive Order 13563, Improving
Regulation and Regulatory Review, which directs federal agencies to ``.
. . review existing rules that may be outmoded, ineffective,
insufficient, or excessively burdensome, and to modify, streamline,
expand, or repeal them in accordance with what has been learned.'' It
also responds to a petition submitted by a coalition representing the
grain elevator industry that, citing the Executive Order, requests the
EPA to review and repeal subpart DD. In considering the directives of
the Executive Order, the EPA conducted several analyses aimed at
determining the effectiveness of subpart DD, determining whether
subpart DD is still relevant and determining whether subpart DD is
excessively burdensome. Based on the results of these analyses, the EPA
concluded that subpart DD is still effective, relevant and not
excessively burdensome but we are proposing some amendments to clarify
certain provisions.

B. Summary of Major Amendments

    Based on the results of the NSPS review, the EPA is proposing the
following:
1. Proposed Clarifications to Subpart DD
    We are proposing amendments to subpart DD to clarify the definition
of grain unloading station and grain loading station, and to clarify
enclosure requirements for barge or ship unloading operations.
2. Proposed New Requirements Contained in Subpart DDa
    We are proposing a new subpart DDa that will include the standards
of performance and other provisions in subpart DD, as clarified in this
proposal which reflect current industry operations, as well as the
following additional new standards and provisions based on our review
of available information:
     An additional method for determining applicability that
includes the storage capacity of temporary storage facilities (TSFs).
     Ten percent opacity standards for barge or ship unloading
stations not using an unloading leg and for column dryers using a wire
screen.
     Particulate Matter (PM) and opacity standards for affected
facilities associated with TSFs consistent with those associated with
permanent storage units.
     Particulate Matter performance tests conducted every 60
months, opacity tests conducted annually, and weekly visual inspections
for affected facilities, and visual inspections of fabric filters every
6 months.
     Records for the new applicability calculation method,
excess emissions events, fabric filter inspections, opacity tests,
weekly visual inspections and PM tests, and the type of grain processed
during performance tests.
     Requirement to submit electronic copies of performance
tests reports to the EPA using the EPA's electronic reporting tool
(ERT).
     New definitions for ``permanent storage capacity,''
``temporary storage facility,'' ``wire screen column dryer,'' and ``en-
masse drag conveyor.''
    We are also proposing that the PM standards are applicable at all
times.

C. Summary of Costs and Benefits

    Table 1 summarizes the costs and benefits of this action. See
section VI of this preamble for further discussion.

   Table 1--Summary of the Costs and Benefits of the Proposed Subpart DDa for New, Modified and Reconstructed
                                       Affected Sources at Grain Elevators
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                                                                                Emission
                Requirement                  Capital cost      Annual cost  ($      reductions      Net benefit
                                             ($ thousand)     thousand/yr) \a\    (tons PM10/yr)
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PM control................................           1,087                   350              31         N/A \b\
Emissions testing and monitoring/reporting               0                   849               0         N/A \b\
 and recordkeeping........................
                                           ---------------------------------------------------------------------
    Total nationwide......................           1,087                 1,199              31         N/A \b\
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\a\ Reporting and recordkeeping costs are in the third year following promulgation. PM control, testing and
  monitoring costs are in the fifth year after promulgation. For the third year after promulgation, the
  associated PM capital cost is $888,000, and annual cost (including annualized PM control cost and emissions
  testing and monitoring) is $757,000.
\b\ Under Executive Order 12866, this rulemaking is not an ``economically significant regulatory action''
  because it is not likely to have an annual effect on the economy of $100 million or more. Therefore, we have
  not conducted a Regulatory Impact Analysis (RIA) for this rulemaking or a benefits analysis. The proposed
  requirements of the New Source Performance Standards (NSPS) for Grain Elevators (Subpart DDa) are anticipated
  to reduce emissions by 31 tons of PM10 each year starting in 2018. While we expect that these PM10 emissions
  reductions will result in improvements in air quality and reduce health effects associated with exposure to
  air pollution resulting from these emissions, we have not quantified or monetized the benefits of reducing
  these emissions for this rulemaking. This does not imply that there are no benefits associated with these
  emission reductions.

II. General Information

A. Does this action apply to me?

    Categories and entities potentially regulated by this proposed rule
include those listed in Table 2 of this preamble.

           Table 2--Examples of Affected Entities by Category
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                                    NAICS \a\    Examples of potentially
            Category                  code         regulated entities
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Industry........................  49313.......  Grain elevators
                                                 (storage).
Industry........................  424510......  Grain elevators
                                                 (merchants,
                                                 wholesalers).
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\a\ North American Industry Classification System.

    This table is not intended to be exhaustive but rather provides a
guide for readers regarding entities likely to be regulated by the
proposed amendments. To determine whether your facility would be
regulated by the proposed amendments, you should carefully examine the
applicability criteria in 40 CFR 60.300 and 40 CFR 60.300a. If you have
any questions regarding the applicability of the proposed amendments 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?

    Submitting CBI. Do not submit information containing CBI to the EPA
through http://www.regulations.gov or email. Clearly mark the part or
all of the information that you claim to be CBI. For CBI information on
a disk or CD-ROM that you mail to the 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 comments that includes information claimed
as CBI, you must submit a copy of the comments that does not contain
the information claimed as CBI for inclusion in the public docket. If
you submit a CD-ROM or disk that does not contain CBI, mark the outside
of the disk or CD-ROM clearly that it does not contain CBI. Information
not marked as CBI will be included in the public docket and the EPA's
electronic public docket without prior notice. Information marked as
CBI will not be disclosed except in accordance with procedures set
forth in 40 Code of Federal Regulations (CFR) part 2. Send or deliver
information identified as CBI only to the following address: Roberto
Morales, OAQPS Document Control Officer (C404-02), OAQPS, U.S.
Environmental Protection Agency, Research Triangle Park, North Carolina
27711, Attention Docket ID Number EPA-HQ-OAR-2010-0706.
    If you have any questions about CBI or the procedures for claiming
CBI, please consult the person identified in the FOR FURTHER
INFORMATION CONTACT section.

III. Background Information

A. What is the statutory authority for these proposed revisions?

    NSPS implement CAA section 111, which requires that each NSPS
reflect the degree of emission limitation achievable through the
application of the BSER which (taking into consideration the cost of
achieving such emission reductions, any nonair quality health and
environmental impact and energy requirements) the Administrator
determines has been adequately demonstrated. This level of control is
referred to as BSER and has been referred to in the past as ``best
demonstrated technology'' or BDT. In assessing whether a standard is
achievable, the EPA must account for routine operating variability
associated with performance of the system on whose performance the
standard is based. See National Lime Ass'n v. EPA, 627 F. 2d 416, 431-
33 (D.C. Cir. 1980).
    We are also proposing in this rulemaking that existing affected
facilities that are modified or reconstructed would be subject to this
proposed rule. 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 the emission rate are not considered
modifications (40 CFR 60.14).
    Rebuilt emission units 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).
    Section 111(b)(1)(B) of the CAA requires the EPA to periodically
review and revise the standards of performance, as necessary, to
reflect improvements in methods for reducing emissions. The NSPS are
directly enforceable federal regulations issued for categories of
sources which cause, or contribute significantly to, air pollution
which may reasonably be anticipated to endanger public health or
welfare. Since 1970, the NSPS have been successful in achieving long-
term emissions reductions in numerous industries by assuring that cost-
effective controls are installed on new, reconstructed or modified
sources.

B. What is the regulatory history for grain elevators?

    In 1978, the EPA promulgated ``Standards of Performance for Grain
Elevators'' (40 CFR part 60, subpart DD) (August 3, 1978, 43 FR 34347).
Since then, we have conducted one review of the standards, which
promulgated minor revisions to clarify certain provisions (March 27,
1984, 49 FR 11750).
    The current subpart DD applies to affected facilities at any grain
storage elevators or grain terminal elevators storing corn, wheat,
sorghum, rice, rye, oats, barley and soybeans which are constructed,
reconstructed or modified after August 3, 1978. On August 7, 1977
Congress amended the Clean Air Act with a provision that exempts
country grain elevators with less than 2.5 million bushels of grain
storage capacity from standards developed under section 111 of the Act.
A ``grain storage elevator'' means any grain elevator

located at any wheat flour mill, wet corn mill, dry corn mill (human
consumption), rice mill or soybean oil extraction plant with permanent
storage capacity of at least one million bushels. 40 CFR 60.301(f). A
``grain terminal elevator'' means any grain elevator with permanent
storage capacity over 2.5 million bushels, except those located at
animal food manufacturers, pet food manufacturers, cereal
manufacturers, breweries and livestock feedlots. 40 CFR 60.301(c). A
``grain elevator'' means any plant or installation at which grain is
unloaded, handled, cleaned, dried, stored or loaded. 40 CFR 60.301(b).
``Permanent storage capacity'' means grain storage capacity which is
inside a building, bin or silo. 40 CFR 60.301(d).
    The affected facilities at grain elevators are each truck unloading
station, truck loading station, barge and ship unloading station, barge
and ship loading station, railcar loading station, railcar unloading
station, grain dryer and all grain handling operations. 40 CFR 60.300.
    The current NSPS, as amended under the 1984 review, include the
following emission limits and work practice standards:

----------------------------------------------------------------------------------------------------------------
                                                                                Requirement (40 CFR
         Type of emissions                Affected facility          Type of standard             60.302)
----------------------------------------------------------------------------------------------------------------
Process emissions..................  Truck unloading station,     PM limit..............  0.01 gr/dscf.
                                      truck loading station,
                                      barge and ship unloading
                                      station, barge and ship
                                      loading station, railcar
                                      loading station, railcar
                                      unloading station, and all
                                      grain handling operations.
                                                                  Opacity limit.........  0%.
                                     Grain dryer................  Opacity limit and       0% opacity for column
                                                                   equipment               dryers equipped with
                                                                   specification.          column plate
                                                                                perforations
                                                                                exceeding 0.094
                                                                                inches, and rack
                                                                                dryers equipped with
                                                                                screen filter coarser
                                                                                than 50 mesh.
Fugitive...........................  Truck loading..............  Opacity limit.........  10%
                                     Truck unloading, railcar     Opacity limit.........  5%.
                                      loading, railcar unloading.
                                     Barge/ship loading.........  Opacity limit.........  20%.
                                     Barge/ship unloading.......  Equipment               Marine leg enclosed
                                                                   specification.          from top to bottom of
                                                                                leg, w/ventilation
                                                                                flow rate of both leg
                                                                                and receiving hopper
                                                                                of 40 ft\3\ per
                                                                                bushel of grain
                                                                                unloaded.
----------------------------------------------------------------------------------------------------------------

    Initial compliance with the PM and opacity emission limits in the
current NSPS (subpart DD) is demonstrated by conducting initial
performance tests. Subpart DD does not contain any continuous
compliance requirements.

IV. Summary of Proposed Amendments

A. What source category is being regulated?

    Today's proposed standards would apply to affected facilities at
any grain storage elevators or grain terminal elevators storing corn,
wheat, sorghum, rice, rye, oats, barley and soybeans which are
constructed, reconstructed or modified after July 9, 2014. We are also
proposing clarifications that would apply to affected facilities at any
grain storage elevator or grain terminal elevator storing corn, wheat,
sorghum, rice, rye, oats, barley and soybeans which are constructed,
reconstructed or modified after August 3, 1978. The affected facilities
at grain elevators are each truck unloading station, truck loading
station, barge and ship unloading station, barge and ship loading
station, railcar loading station, railcar unloading station, grain
dryer and all grain handling operations. Neither the proposed standards
nor the clarifications to the existing standards are changing the rules
for currently affected facilities, however the proposed standards will
cover a new type of barge unloader and column dryer not contemplated by
the existing standards.

B. What pollutants are emitted from these sources?

    The primary pollutant emitted and the only pollutant regulated by
the grain elevator NSPS is PM. Particle pollution can cause serious
health problems. The size of particles is directly linked to their
potential for causing health problems. EPA's national and regional
rules to reduce emissions of pollutants that form particle pollution
will help state and local governments meet the Agency's national air
quality standards. Particulate matter is emitted from grain as it is
conveyed from one affected facility to another, unloaded or loaded onto
transport vessels and during the drying process. Opacity is regulated
to ensure proper operation and maintenance of the PM controls and to
control fugitive emissions.
    The PM concentration limits are based on filterable PM measured by
EPA Method 5. Filterable PM consists of those particles directly
emitted by a source as a solid or liquid at the stack (or similar
release conditions) and captured on the filter of a stack test train. A
fraction of the PM emitted from grain elevator affected facilities is
PM with an aerodynamic diameter less than or equal to 2.5 micrometers
(PM2.5). The EPA is not proposing separate standards for
PM2.5 in this action because the available emissions test
data for PM2.5 are limited and not adequate for setting
standards.
    The PM concentration limits in today's proposed NSPS review are
based on filterable PM measured by EPA Method 5 because the majority of
PM emissions data available are Method 5 data. Emissions of condensable
PM, which is PM that is not directly emitted but is formed in the
atmosphere, are measured using EPA Method 202. These emissions can be
added as the ``back half'' to a Method 5 sampling train. However, the
EPA is not proposing separate standards for condensable PM because
available emissions test data for condensable PM are limited and not
adequate for setting standards.

C. What are the proposed standards?

    The EPA is proposing the following actions regarding the NSPS for
grain elevators. As summarized in section IV.C.1 of this preamble, we
are proposing clarifications to specific

requirements in subpart DD. As summarized in section IV.C.2 of this
preamble, we are also proposing a new subpart DDa which would only be
applicable to affected facilities that commence construction,
modification or reconstruction after July 9, 2014.
1. Clarifications to Subpart DD
    We are proposing clarifications to three provisions in subpart DD.
These proposed clarifications are summarized in Table 3 of this
preamble, which presents both the current provision in subpart DD and a
description of the proposed clarifications. EPA's rationale for these
proposed changes is provided in section V.D. of this preamble. These
proposed revisions are intended to keep the meaning and intent of the
definitions as originally promulgated while making sure the definitions
encompass the changes in the industry since the last review of subpart
DD in 1984.

   Table 3--Summary of Proposed Amendments to Subpart DD for Affected
      Facilities That Have Commenced Construction, Modification, or
                   Reconstruction After August 3, 1978
------------------------------------------------------------------------
                                         Proposed revision to subpart DD
                                           for affected facilities that
 Current subpart DD provision (subpart     have commenced construction,
              DD citation)               modification, or reconstruction
                                               after August 3, 1978
------------------------------------------------------------------------
``Grain unloading station'' is defined   ``Grain unloading station'' is
 to be that portion of a grain elevator   that portion of a grain
 where the grain is transferred from a    elevator where the grain is
 truck, railcar, barge or ship to a       transferred from a truck,
 receiving hopper (Sec.   60.301(j)).     railcar, barge or ship to a
                                          receiving hopper or to the
                                          grain handling equipment that
                                          connects the unloading station
                                          to the rest of the grain
                                          elevator, including all of the
                                          equipment, support structures
                                          and associated dust control
                                          equipment and aspiration
                                          systems connected to or
                                          required to operate the grain
                                          unloading station.
``Grain loading station'' is defined to  ``Grain loading station'' is
 mean that portion of a grain elevator    that portion of a grain
 where the grain is transferred from      elevator where the grain is
 the elevator to a truck, railcar,        transferred from the elevator
 barge or ship.( Sec.   60.301(k)).       to a truck, railcar, barge or
                                          ship, including all of the
                                          equipment, support structures
                                          and associated dust control
                                          equipment and aspiration
                                          systems connected to or
                                          required to operate the grain
                                          loading station.
For affected barge or ship unloading     For affected barge or ship
 stations, the unloading leg is           unloading stations, the
 required to be enclosed from the top     requirements in Sec.   60.302
 (including the receiving hopper) to      (d)(1) remain the same except
 the center line of the bottom pulley     that a new provision is
 and ventilation to a control device is   proposed to be added to
 required to be maintained on both        clarify that where aspiration
 sides of the leg and the grain           of the casing provides dust
 receiving hopper. (Sec.   60.302         control at the boot of the
 (d)(1)).                                 conveyor and a receiving
                                          hopper is not used, the
                                          unloading leg is required to
                                          be enclosed from the top to
                                          the center line of the bottom
                                          pulley, and ventilation to a
                                          control device is required to
                                          be maintained on both sides of
                                          the leg.
------------------------------------------------------------------------

    The proposed clarifications are applicable to all affected
facilities that commenced construction, modification or reconstruction
after August 3, 1978.
2. Proposal of Subpart DDa
    We are proposing a new subpart DDa for affected facilities that
commence construction, modification, or reconstruction after July 9,
2014. Subpart DDa includes the standards in subpart DD, including the
clarifications discussed in Table 3 of this preamble for subpart DD,
and new requirements for affected facilities. The proposed new
requirements are summarized below. EPA's rationale for these proposed
changes is provided in sections V.A through V.D. of this preamble. The
new requirements include a new definition of permanent storage capacity
that accounts for storage capacity from TSFs; other new definitions;
emission standards for two new subcategories; and testing, monitoring,
reporting and recordkeeping requirements. We are also proposing a
requirement in subpart DDa that all emission standards in subpart DDa
apply at all times, including periods of SSM.
Definitions
    We are proposing the following definitions:
    ``Permanent storage capacity'' is proposed to be the grain storage
capacity calculated using proposed Equations 1 or 2, as applicable.
This proposed definition revises the method used to determine
applicability by providing a new method to calculate ``permanent
storage capacity'' using TSF capacity and the grain storage capacity of
buildings, other types of bins and silos. Equation 1 is proposed for
grain elevators where the grain storage capacity and historical grain
throughput for all their grain storage buildings, bins and silos are
known.
[GRAPHIC] [TIFF OMITTED] TP09JY14.005

Where:

Ctp = Total permanent storage capacity of all buildings,
bins (including TSFs) and silos used to store grain (bushels).
Cp = Total storage capacity of all buildings, bins
(excluding TSFs) and silos used to store grain (bushels).
Tp = Maximum annual throughput of grain for all
buildings, bins (excluding TSFs) and silos used to store grain
(bushels per year) over the previous 5 years.
Ct = Total storage capacity of all TSFs used to store
grain (bushels).

    Equation 2 is proposed for grain elevators where the grain storage
capacity and historical grain throughput for all grain storage
buildings, bins or silos are not known. Equation 2 would be used at
grain elevators that had at least one storage building, bin, or silo
that did not exist prior to the date of construction, modification or
reconstruction of the affected facility.

Ctp = Cp + (0.34 * Ct) (Eq. 2)

Where:
Ctp = Total permanent storage capacity of all buildings,
bins (including TSFs) and silos used to store grain (bushels).
Cp = Total storage capacity of all buildings, bins
(excluding TSFs) and silos used to store grain (bushels).
Ct = Total storage capacity of all TSFs used to store
grain (bushels).
0.34 = Default ratio of permanent grain storage capacity to annual
throughput

    ``Grain unloading station'' is proposed as specified in Table 3 of
this preamble.
    ``Grain loading station'' is proposed as specified in Table 3 of
this preamble.
    ``Temporary storage facility'' or ``TSF'' is proposed to be defined
as any grain storage bin that: (1) Uses an asphalt, concrete or other
improved base material; (2) uses rigid, self-supporting

sidewalls; (3) provides aeration; and (4) provides a covering or tarp.
    ``Wire screen column dryer'' is proposed to be defined to be any
equipment used to reduce the moisture content of grain in which the
grain flows from the top to the bottom in one or more continuous packed
columns between two woven wire screens or between a combination of
perforated metal sheets and wire screens.
    ``En-masse drag conveyor'' is proposed to mean a device that uses
paddles or flights mounted on a chain to remove grain from a barge or
ship.
    ``Portable equipment'' is proposed to mean equipment that includes
(but is not limited to) portable augers, portable conveyors and front-
end loaders that are not fixed at any one spot and can be moved around
the site.
PM Standards
    We are proposing the following actions regarding the PM standards:
     Maintain the subpart DD standards for ``rack dryers'' and
``column dryers'' and add a provision that ``wire screen column
dryers'' are prohibited from discharging into the atmosphere any gases
that exhibit greater than 10-percent opacity.
     Clarify the requirements for barge and ship unloading
stations using an unloading leg as specified in Table 3 of this
preamble.
     Add an opacity limit of 10 percent for all affected
facilities at barge and ship unloading stations that unload grain using
en-masse drag conveyors.
     Require that requests for an equivalency determination for
alternative controls for barge unloading stations apply only to barge
unloading stations that do not use an unloading leg or en-masse drag
conveyor.
     Add a requirement that unloading facilities and grain
handling operations at TSFs meet the subpart DD requirements for PM
(0.01 gr/dscf) and opacity (5 percent for truck unloading and 0 percent
for grain handling) if portable equipment is not used.
     Add a requirement that the standards of subpart DDa apply
at all times including periods of SSM.
Test Methods and Procedures
    We are proposing the following actions to test methods and
procedures:
     Annual opacity testing be conducted for each applicable
opacity limit for each affected facility (using Method 9).
     PM testing be conducted every 60 months for each
applicable PM limit for each affected facility (using Method 5 or 17).
Reporting Requirements
    We are proposing that, within 60 days of each performance test, the
results of the performance test be submitted electronically to the EPA
using the Compliance and Emissions Data Reporting Interface (CEDRI)
that is accessed through the EPA's CDX (https://cdx.epa.gov/).
Performance test data would be required to be submitted in the file
format generated through use of the EPA's ERT (see http://www.epa.gov/ttn/chief/ert/index.html). This requirement only applies to the EPA
test methods that are ERT-compatible. These methods are listed on the
ERT Web site.
Startup, Shutdown and Malfunction Requirements
    The General Provisions in 40 CFR part 60 provide that emissions in
excess of the level of the applicable emission limit during periods of
SSM shall not be considered a violation of the applicable emission
limit unless otherwise specified in the applicable standard. See 40 CFR
60.8(c). The General Provisions, however, may be amended for individual
subparts. Here, the EPA is proposing standards in subpart DDa that
apply at all times as specified in the proposed Sec.  60.302a(e). This
is discussed further in section V.C.3, and with respect to specific
standards in various sections below.
Monitoring Requirements
    We are proposing the following new monitoring requirements:
     Fabric filter/baghouse inspections every 6 months.
     Weekly visible emissions checks of affected facilities.
Recordkeeping Requirements
    We are proposing the following new records:
     Total storage capacity (bushels) for each building, bin
(excluding TSFs), and silo used to store grain.
     Storage capacity for each TSF.
     Calculations documenting the emissions quantification for
excess emission events.
     Results of fabric filter/baghouse inspections and any
corrective action taken maintained on-site.
     Results of weekly visible emission checks, including any
corrective action taken. Records maintained on site for a minimum of 36
months.
     Results of the annual opacity tests.
     The type of grain processed during performance tests at
the affected facility.

V. Rationale for Proposed Amendments

    CAA section 111(a)(1) requires that standards of performance for
new sources reflect the ``. . . degree of emission limitation
achievable through the application of the best system of emission
reduction which (taking into account the cost of achieving such
reduction, and any nonair quality health and environmental impacts and
energy requirements) the Administrator determines has been adequately
demonstrated.''
    Section 111(b)(1)(B) of the CAA requires the EPA to review and
revise, if appropriate, NSPS standards. Accordingly, we conducted the
following evaluations as part of our review of subpart DD:
     We conducted a BSER analysis for the grain elevator source
category.
     We evaluated the method for determining applicability
under subpart DD.
     We evaluated whether any changes are needed to the subpart
DD compliance requirements.
     We evaluated subpart DD for any provisions that need
clarification.
    We are proposing minor revisions to subpart DD that would apply
retrospectively to all facilities that currently are subject to subpart
DD. We are also proposing a new subpart DDa that would apply to
affected facilities that commence construction, modification or
reconstruction after July 9, 2014. The proposed requirements in subpart
DDa include the clarifications we are proposing to subpart DD as well
as some substantive new requirements. Our decision to propose revisions
to subpart DD and propose a new subpart DDa is explained in detail in
sections V.A through D of this preamble.

A. How did the EPA conduct the BSER analysis?

    A performance standard reflects the degree of emission limitation
achievable through the application of the BSER that the EPA determines
has been adequately demonstrated, taking into consideration costs,
nonair quality health and environmental impacts and energy
requirements.
    We conducted the BSER review by first assessing changes that have
occurred to the grain elevator source category since the last review of
the NSPS in 1984. We then identified currently used, new and emerging
control systems and assessed whether they represent advances in
emission reduction techniques compared to the control techniques used
to comply with the existing NSPS. For each new or emerging control
option identified, we then evaluated emission reductions, costs, energy
requirements and non-air quality impacts. The results of these
considerations are presented in section V.A.1 of this preamble.

1. Evaluation of Grain Elevator Source Category for Significant Changes
to Emission Sources
    The EPA gathered information from various sources to identify
significant changes that have occurred to the grain elevator source
category since the last NSPS review. We reviewed several sources of
information, including responses from an industry survey, information
in the RACT/BACT/LAER Clearinghouse (RBLC), requirements in state rules
and additional information collected from the grain elevator industry.
Sections V.A.1.a through V.A.1.d of this preamble describe our review
of each source of information and section V.A.1.e of this preamble
presents the results of the EPA's evaluation of these sources including
any significant changes identified.
a. CAA Section 114 Information Collection Request
    To characterize the current state of emissions, practices,
operations and controls in the industry, we conducted a CAA section 114
ICR in 2009 for grain elevator operations. The survey was addressed to
facilities with any grain elevator that would constitute a ``grain
terminal elevator'' or a ``grain storage elevator'' (as defined in 40
CFR 60.301). To gather general background information about the
industry, respondents were required to submit information for
facilities based on storage type, grain(s) handled and the EPA region.
Survey responses were collected from 121 grain elevators. The survey
responses provided information on grain elevator capacity, grain
elevator throughputs for three successive years, the use of temporary
storage facilities, barge unloading operations, dryer design, general
information on facility characteristics and control devices and work
practices used to reduce PM emissions from various sources. The survey
responses and database developed from the response information are in
the grain elevator docket at EPA-HQ-OAR-2010-0706.
b. Review of the RACT/BACT/LAER Clearinghouse
    The EPA established the RBLC as a repository of information on air
pollution control technologies required by state air pollution control
programs (including past RACT, BACT and LAER decisions). Reasonably
Available Control Technology is required on existing sources in areas
that are not meeting national ambient air quality standards (i.e., non-
attainment areas). Under the New Source Review (NSR) program, BACT is
required on new or modified major sources in attainment areas and LAER
is required on new or modified major sources in non-attainment areas.
We reviewed the RBLC to identify any new control technologies that have
been used at grain elevators since the last review of the rule. Results
of the RBLC review are discussed in the memorandum, ``Evaluation of the
Revisions to Grain Elevator Emission Standards'' in the grain elevator
docket at EPA-HQ-OAR-2010-0706.
c. Review of State Regulations
    In order to assess whether state regulations provide more stringent
emission limits or additional controls than subpart DD, we conducted a
review of the regulations from the 12 states with the most grain
storage capacity and the largest number of grain elevators in
operation. The 12 states are: Iowa, Illinois, Minnesota, Nebraska,
Kansas, Indiana, North Dakota, South Dakota, Ohio, Texas, Missouri and
Wisconsin. We reviewed each state's grain elevator standards and
evaluated other state regulations controlling PM, opacity and fugitive
dust emissions that may be applicable to grain elevators. The review of
state rules is presented in the memorandum, ''Evaluation of Grain
Elevator Emission Standards in Response to Executive Order 13563'' in
the grain elevator docket at EPA-HQ-OAR-2010-0706.
d. Other Data Gathering Activities
    The EPA conducted several meetings with a coalition representing
grain elevators owners and operators. Members of the coalition provided
information on current practices and provided technical presentations
to the EPA. The technical presentations and coalition submittals are
contained in the grain elevator docket at EPA-HQ-OAR-2010-0706.
e. Results of Evaluations
    Based on our review of the state rules, we identified no
requirements more stringent than those in subpart DD. Our review of the
RBLC did not identify any control techniques that are different from
the control techniques used by grain elevators to comply with the
subpart DD standards. Our review of the survey responses and
information gathered at meetings resulted in identifying: (1) Emissions
test reports and one control technique that we determined not to be
BSER for affected facilities as explained below, and (2) several new
emission sources since subpart DD was last reviewed in 1984. Section
V.A.e.2 discusses our evaluation of new information collected for
existing affected facilities. Section V.A.e.3 discusses our evaluation
of the new emission sources. Both evaluations are documented in the
memorandum, ``Evaluation of the Revisions to Grain Elevator Emission
Standards'' in the grain elevator docket at EPA-HQ-OAR-2010-0706.
2. BSER Evaluation for Subpart DD Affected Facilities
    Subpart DD regulates the following affected facilities: grain
dryers, grain handling, grain loading stations (trucks, railcars and
barges/ships) and grain unloading stations (trucks, railcars and
barges/ships). Subpart DD requires affected facilities, except grain
dryers, to meet a PM emission limit of 0.01 gr/dscfm for process
emissions (i.e., non-fugitive emissions). All affected facilities are
also required to meet opacity limits, specific to each affected
facility, to control fugitive dust emissions. As discussed earlier, we
did not identify any more stringent state requirements or more advanced
emission control technology from the RBLC for these affected
facilities.
    Some of the grain elevators responding to the 2009 CAA section 114
survey also provided emissions test reports and permit information. We
evaluated the PM emissions test reports to determine whether the PM
emission limits in subpart DD were reflective of emissions from well-
controlled facilities. The survey responses, permit information and
information collected from a literature search provided information on
application of mineral oil as a dust suppression technique to reduce
fugitive PM emissions. We conducted a BSER analysis for fugitive
emissions considering the application of mineral oil to grain.
    The results of the BSER analysis showed that for fugitive sources,
the limited information available did not indicate any advances in
emission control techniques that support changing the current NSPS
requirements, including the application of mineral oil. An emission
limit developed using the emissions data collected with the survey
responses resulted in an achievable limit that is the same as the limit
in subpart DD. Our detailed review is discussed in V.A.2.a and V.A.2.b
of this preamble.
    No other emission control technologies or work practices have been
identified for reducing emissions from affected facilities at grain
storage or grain terminal elevators. Based on these results, consistent
with our obligations under CAA section 111(b), we propose that the
control techniques and resultant emission reductions on

which the current NSPS is based still represent BSER.
a. Review of PM Emission Limit
    We conducted a BSER analysis to determine if we should propose a
different PM emission limit for newly constructed, modified, and
reconstructed affected facilities at grain elevators. Subpart DD
requires process emissions from affected facilities (e.g., truck
unloading stations, grain handling operations, etc., but excluding
grain dryers) to meet a PM emission limit of 0.01 grains per dry
standard cubic foot (gr/dscf). Grain elevators typically meet the
standard using fabric filters.
    The EPA estimates between 340 and 920 grain elevators could be
subject to Subpart DD. In 2009, EPA sent CAA section 114 surveys to 120
grain elevators to characterize the industry and obtain data on PM
emission control techniques and associated emissions. Respondents to
the survey provided PM emission test reports from 15 grain elevators,
which represent only approximately 1.6 percent to 4 percent of the
grain elevators potentially subject to subpart DD. We first evaluated
the test reports to determine whether sufficient information existed to
propose revisions to the PM emission limit. The 15 grain elevators who
submitted test reports for PM emissions controlled with fabric filters
submitted those reports for the following affected facilities: (1) 7
railcar unloading stations; (2) 4 truck unloading stations; (3) 3 grain
handling operations; and (4) 2 barge unloading stations. The survey
results indicated that a typical grain elevator has on average 2 truck
unloading stations, 4 grain handling operations, 1 barge unloading
station, and 1 railcar unloading station. Information provided in the
survey responses also indicated that approximately 75 percent of
railcar unloading stations, truck unloading stations, barge unloading
stations, and grain handling operations are subject to subpart DD.
Applying the typical counts to the estimated range of grain elevators
that could be subject to subpart DD, and accounting for the fraction
that could be subject to subpart DD, the number of affected facilities
potentially subject to subpart DD is between 2,200 and 6,200. Comparing
these numbers to the number of tests reports collected, we estimated
that the facilities submitting PM emission test reports account for
only approximately 0.3 percent to 0.7 percent of the population of
railcar unloading stations, truck unloading stations, grain handling
operations, and barge unloading stations at grain elevators that could
be subject to subpart DD. Additionally, the test reports do not include
any tests conducted at barge/ship loading stations, railcar loading
stations, or truck loading stations.
    We further evaluated the PM emission levels from the available test
reports, measured as an average of three test runs, which ranged from
0.01 to 0.00002 gr/dscf. It appears the wide variation in PM emissions
is due to the different affected facilities that were tested, other
operational considerations (i.e., speed of the process) and grain
characteristics. EPA had previously concluded that the amount of dust
emitted during processing of grain in the various affected facilities
depends on the type of grain being handled, the quality of the grain,
and the moisture content of the grain.\1\ The emission test information
gathered for the 1978 subpart DD proposal \2\ indicates that the type
of grain processed affects the PM emissions, with one to two orders of
magnitude difference in PM emissions between affected facilities
processing soybeans and corn (higher emissions) than those processing
wheat and milo. The PM emission limit in the grain elevator NSPS covers
eight different grains. However, it does not appear that the emission
tests for the 15 grain elevators cover all the 8 grains. Many of the
test reports do not indicate the grain type being processed during the
test.
---------------------------------------------------------------------------

    \1\ Compilation of Air Pollution Emission Factors. Chapter 9.9.1
Grain Elevators and Processes.
    \2\ 1978 BID, Chapter 5.
---------------------------------------------------------------------------

    In considering the limited data and the limitations of the data, we
concluded that the PM emission test reports do not sufficiently
characterize the performance of fabric filters controlling PM from the
full range of affected facilities subject to subpart DD. Accordingly,
we have determined that there is insufficient available information to
support proposed revisions to the PM emission limits. We are therefore
proposing to maintain the PM limit at 0.01 gr/dscf.
    We believe the limited number of test reports submitted is due to
the current subpart DD only requiring one initial emission test of an
affected facility. As discussed in Section V.C.1 of this preamble, EPA
believes that additional testing is needed to ensure compliance with
the emission limit. We are therefore proposing, in subpart DDa, to
require repeat testing of affected facilities every five years. Not
only will these tests help the sources determine compliance with the
standards, they will provide a more robust set of information for when
this rule is next reviewed. We estimate that by the next 8 year review
of subpart DDa, initial PM emission tests may be conducted on as many
as 300 affected facilities and repeat testing may be conducted on as
many as 120 affected facilities, providing approximately 420 PM
emission tests to evaluate for determining whether to revise the PM
limit. We are also proposing that the emission tests be conducted while
processing the highest PM emitting grains to establish PM emissions for
all operating scenarios that are expected to occur. We are also
proposing to require records of the grain type processed during the
testing.
b. Application of Mineral Oil
    A few permits submitted with responses to the CAA section 114
surveys indicate that some grain elevators use mineral oil as a
fugitive dust suppression technique. Mineral oil application is
primarily used to reduce the possibility of a grain elevator explosion
caused by dust.
    The EPA has previously studied the application of mineral oil at
grain elevators, noting that there were several potential benefits,
such as reduced dust disposal cost, less grain weight loss, as well as
improved safety in the working environment.\3\ However, compared to
currently used technology for controlling process emissions, i.e.,
fabric filters, the study indicated that oil application systems were
not as effective as fabric filters in reducing PM. The EPA also
concluded that the emission tests conducted were inadequate for the
purpose of determining emissions and developing emission factors
because they were pilot studies or controlled tests. Therefore, mineral
oil application as a replacement for existing controls has not been
demonstrated to be a feasible control option. We do not have
information on the appropriateness or effectiveness of using mineral
oil in combination with existing technologies, such as fabric filters.
---------------------------------------------------------------------------

    \3\ Oil Suppression of Particulate Matter at Grain Elevators.
U.S. Environmental Protection Agency. EPA-453/R-94-049. July 1994.
---------------------------------------------------------------------------

    The subpart DD fugitive emission standards require meeting a 0
percent opacity limit for grain handling operations and require
opacities ranging from 5 to 20 percent for loading and unloading
stations. We do not have information on how mineral oil application
would affect the fugitive opacity limits, e.g., whether the opacity
levels would decrease to 0 percent, stay the same or result in another
limit. Additionally, portable grain handling equipment, such as
portable augers,

portable conveyors and front-end loaders are often used at grain
elevators. We do not have information on whether mineral oil
application is feasible or would reduce emissions at facilities that
use portable grain loading equipment to reduce fugitive emissions. The
size and design of these systems may affect both their ability and the
time necessary to mix mineral oil thoroughly with grain to be an
effective dust suppression technique.
    The EPA mineral oil study also noted that there are concerns
regarding the effect the oil has on grain quality, and consequently,
its price. The EPA study indicates that mills and distilleries are
concerned about the long-term effects of oil on grain. For some grains,
the use of mineral oil may be more problematic, such as for wheat in
the milling process. In addition, grain exported to other countries may
be required to meet hydrocarbon levels and grain not meeting those
levels may be considered contaminated. For example, the European
Union's code of practices states that any detection of a level of
mineral oil above 300 mg/kg is considered to be contaminated by mineral
oil. Therefore, mineral oil application might not be economically
feasible for all grains and may result in product quality and
contamination concerns.
    EPA has only limited information on the effectiveness and cost of
mineral oil application, and no test information. We have concluded
that mineral oil application as a dust suppression technique for
limiting emissions from fugitive sources has not been demonstrated.
Therefore, we are not proposing a requirement to use mineral oil. We
are requesting additional information on the effectiveness of mineral
oil in combination with existing controls and when applied at fugitive
sources regulated by the NSPS, particularly those associated with
portable grain handling equipment. We are also soliciting information
on the capital and operating cost of mineral oil application systems
and any problems in grain quality associated with using mineral oil.
3. BSER Evaluation for New or Significantly Changed Emission Sources
    Our review of the survey responses and presentations by
representatives of the grain elevator industry identified the following
three significant changes that have occurred to grain elevators since
the last review of subpart DD in 1984:
     Use of new barge unloading technologies (e.g., en-masse
drag conveyors).
     Use of wire screen column dryers.
     Use of TSFs.
    We evaluated each of the changes to determine if they result in new
emission sources, and, if so, whether existing subpart DD requirements
represent BSER. To assess BSER, we: (1) Identified available control
measures applicable to each emission source; and (2) evaluated these
measures to determine emission reductions achieved, associated costs,
nonair environmental impacts, energy impacts and any limitations to
their application. The evaluation is presented in sections V.A.3.a
through V.A.3.c of this preamble. The BSER analysis is documented in
the memorandum, ``Evaluation of the Revisions to Grain Elevator
Emission Standards'' in the grain elevator docket at EPA-HQ-OAR-2010-
0706.
a. New Unloading Operation Emission Sources at Barges--En-Masse Drag
Conveyors
    Barge unloading stations are an affected facility regulated by
subpart DD. Subpart DD standards for barge and ship unloading were
established for a specific type of unloading mechanism, referred to as
either a marine leg or bucket elevator. Under subpart DD, process
emissions caused by unloading using a marine leg/bucket elevator must
be controlled by enclosing the marine leg/bucket elevator from the top
to the bottom of the leg. Emissions must be vented to a control device
using a ventilation flow rate of 40 ft\3\ per bushel of grain unloaded
for both the marine leg/bucket elevator and receiving hopper. Subpart
DD also provides for an equivalency determination in situations where
it is not possible to meet the design standards. Since the EPA's last
review of subpart DD, several new barge unloading mechanisms have been
developed and used, at least one of which does not utilize a bucket
elevator or marine leg, and, as such, cannot use the design standards.
    Some barge unloading stations currently use en-masse drag
conveyors, which were not in use the last time we reviewed subpart DD.
En-masse drag conveyors operate under a different principle than bucket
elevators or marine legs. En-masse drag conveyors are plug-flow drag
conveyors that are designed to operate vertically. The conveyor uses
paddles or flights mounted on a chain to move grain. The side of the
conveyor where the grain is being transferred is filled with grain.
This type of unloader is significantly different than a bucket
unloading leg which has open space between each bucket and can
therefore be enclosed and ventilated to a control device. Therefore,
dust aspiration to meet the design ventilation requirement of 40 ft\3\
per bushel of grain is not feasible for en-masse drag conveyors because
there is no headspace for air passage to the grain inlet at the base of
the conveyor. Additionally, the normal mode of operation is to bury the
conveyor inlet into the grain being unloaded, which eliminates the need
for dust aspiration at this point. These types of unloaders are
becoming more common as they are more efficient than the bucket
unloaders--both in the movement of more grain in less time and also
requiring fewer personnel for the operation. Particulate emissions are
controlled by the design of the unloader (burying inlet in grain)
without an add-on emission control system. This newer unloading system
was developed for a variety of reasons, including faster unloading
rates, higher capacity unloading, cost savings and other site-specific
reasons.
    Section 111 of the CAA makes an allowance for the EPA to
subcategorize source categories based on differences in size, type and
class. An en-masse drag conveyor is a different type of barge unloading
system than the marine leg or bucket elevator due to the differences in
the unloading mechanism. As such, en-masse drag conveyors constitute a
new subcategory of barge unloading system. All emissions from barge
unloading using an en-masse drag conveyor are fugitive in nature
because they cannot be captured and ventilated to a control device.
Some barges have a small opening where the en-masse drag conveyor
enters and those openings can be covered around the en-masse loader,
thereby limiting fugitive emissions. Other barges have a large opening
where a bulldozer is lowered into the barge to move grain toward the
unloader. This type of application of the en-masse drag conveyor does
not allow openings to be covered, due to safety requirements. No other
technologies or techniques have been identified to control fugitive
emissions from barge unloading.
    The EPA collected test results from two one-hour method 9 tests for
opacity conducted at one en-masse system (loading into the barges with
larger openings) to demonstrate equivalency with the current standards,
per the requirements in 60.302(d)(3) of subpart DD. Method 9 requires
that opacity readings be recorded to the nearest 5 percent at 15-second
intervals. Opacity is determined as an average of 24 consecutive
observations, i.e., a set of observations. The average opacity levels
during the highest set of observations of each test were 8.75 and 9.79
percent. Because method 9 opacity

measurements are taken in increments of 5 percent, a limit based on the
opacity tests must be rounded to the nearest multiple of five. For the
tests reviewed, the resulting emission limit is 10 percent opacity. The
EPA did not receive any information regarding whether there would be
any cost associated with meeting the limit (other than testing and
recordkeeping and reporting), or receive any information regarding
whether there would be any emission reductions. However, a comparison
between the opacity limit calculated and the data collected from the
en-masse conveyor show that the 10 percent opacity limit can be met by
affected facilities using the en-masse conveyor system to unload barges
without additional control, resulting in no cost or emission impacts
for meeting the opacity limit. Additionally, we do not expect there to
be any non-air quality health and environmental impacts associated with
the limit, nor any changes in energy usage or emissions of any other
pollutant.
    Based on our evaluation, we are proposing a new subcategory for
barge unloading stations--barge unloading stations with an en-masse
drag conveyor. Based on these results, consistent with our obligations
under CAA section 111(b), we are proposing that the 10 percent opacity
limit represents BSER for en-masse drag conveyors used to unload grain
from barges. We are also proposing that such systems be required to
meet an opacity limit of 10 percent at all times.
    We expect that en-masse drag conveyor systems that have a small
opening could achieve a lower level of opacity if the opening was
covered; however, we do not have sufficient data to establish a
different opacity limit for these systems. We do not have information
on the effectiveness of the cover, costs of the cover, procedures for
using the cover or if there are operational or health issues that may
occur if the opening is covered. We are requesting additional
information to evaluate this control option.
    Subpart DD contains provisions that allow for alternative methods
of control for barge unloading stations instead of meeting the
requirements for unloading legs. We are also proposing similar
provisions for subpart DDa. We are proposing that affected barge
unloading stations not using an unloading leg or an en-masse drag
conveyor may use other methods of emission control that are
demonstrated to the Administrator's satisfaction to reduce emissions of
PM to the same level or less than the standards for barge unloaders
using marine legs or en-mass drag conveyors.
    The EPA requests comment on all aspects of the BSER determination
for barge unloading using an en-masse drag conveyor. We also request
comment on whether there are other types of barge unloading systems
that should be considered for subcategorization. If so, the EPA
requests information on control technologies that may be used on the
unloading system, costs, emission reductions associated with the
control and emissions test information for them. The EPA also requests
information on technologies or practices that may be used to control
emissions from barge unloading using an en-masse conveyor system and
additional opacity tests conducted at en-masse conveyor systems.
b. New Wire Screen Column Dryers
    Grain dryers are an affected facility under subpart DD. The subpart
DD emission limits for dryers were established for two types of grain
dryers used at grain elevators: rack dryers and column dryers. Grain
column dryers are defined as equipment used for drying the grain in
which the grain flows by gravity from the top of the dryer to the
bottom in one or more packed columns between two perforated metal
sheets. Subpart DD requires that PM emissions from grain dryers be
reduced by meeting an opacity limit of 0 percent if a column dryer uses
column plate perforations exceeding 0.094 inches, or if a rack dryer
passes exhaust gases through a screen filter coarser than 50 mesh.
    In its review of the grain elevator industry, the EPA found that an
additional type of column grain dryer not addressed in subpart DD is
now being used. Most rice dryers currently use column dryers with woven
wire mesh screens in place of, or in addition to, perforated plates
because perforated plates damage the rice kernel, are less efficient
for rice drying and are not durable. All the wire mesh column dryers
reported in response to the ICR except one are used for drying rice.
The wire screens also allow for air transport from the dryer while
entrapping PM from the rice. Information provided by one company drying
rice shows that of the 126 dryers they operate, 115 are column dryers;
115 of all the dryers (column and rack) use a wire screen of 24 mesh
size, and 9 use a 50 mesh size for controlling PM emissions (50 mesh is
a smaller screen size than 24 mesh). The 50 mesh screens are being
replaced over time because of maintenance and plugging problems.
    After an evaluation of the differences in size, type and class of
column dryers, per CAA section 111, the EPA is proposing that wire
screen column dryers constitute a new subcategory of grain dryers
because they are a different type of dryer to which subpart DD does not
apply.
    Emissions from grain dryers are fugitive in nature. It is not
possible to fully enclose grain dryers and vent PM emissions to a
control device because of the large size of the dryer, the way that PM
is emitted (through the side walls of the dryer rather than from a
stack or vent), and because the dryer needs sufficient air flow to work
properly and an enclosure would restrict the airflow. Therefore, there
are no add-on controls that can be applied to control PM emissions from
these dryers. The PM emitted is a function of the size of the openings
on the dryer sidewalls. Larger openings emit more PM. The current
industry practice is to use wire screens of 24 mesh size to reduce the
size of the openings, resulting in reducing PM emissions.
    The BSER for rice dryers is to use a wire screen size of 24 mesh,
as it reduces PM emissions and also allows proper operation of the
dryer. We identified no regulatory options that are more stringent and
are technically viable. Higher mesh sizes (e.g., 50, 100) are available
that would have smaller openings, resulting in even more emissions
reductions. However, information from one rice facility indicates that
the 50 mesh screens cause plugging problems and choke the airflow of
the dryers and require substantial maintenance to clean. The EPA also
determined, during the development of subpart DD in 1978, that the
higher sizes, such as 100 mesh screens, would restrict air flow and
result in more plugging of the openings such that there would be an
unreasonable cost impact due to the need to clean the screens
frequently, reduced drying performance and additional energy
requirements. Those determinations are still true today.
    The EPA collected opacity information for four column dryers with
24 mesh wire screens for drying rice. The opacity data for these dryers
consist of one run of 30 minutes of observation for each dryer. The
average opacities for the four dryers ranged from 1.13 to 8.38 percent,
with the average opacities for the highest period of observation
ranging from 5 to 10 percent. After rounding to the nearest increment
of 5 percent, the corresponding opacity limit based on the data from
the four rice dryers is 10 percent. Based on the information collected,
this level is achievable by all wire screen column dryers using 24
mesh.
    Because this limit is achievable by the wire screen column dryers
that

provided information, and these dryers would be similar or the same as
future dryers constructed (i.e., wire screen column dryers using 24
mesh), we estimated there to be no cost or emission impacts from
meeting a 10 percent opacity limit (other than testing, recordkeeping
and reporting costs). The addition of wire screen of 24 mesh to column
dryers is an equipment design feature that reduces PM instead of a
separate add-on control device where emissions are vented. The wire
screens would not generate secondary pollutant emissions or result in
increased energy use. Therefore, the EPA estimated no nonair quality
health and environmental impacts associated with the limit nor any
changes in energy usage or emissions of any other pollutant.
    Based on this evaluation, we are proposing a new subcategory of
wire screen column dryers in subpart DDa with an opacity limit of 10
percent for this subcategory. Based on these results, consistent with
our obligations under CAA section 111(b), we propose that an opacity
limit of 10 percent represents BSER for wire screen column dryers and
are proposing standards for wire screen column dryers in subpart DDa.
    We have information from one Method 9 test conducted during filling
and emptying operations for one wire screen column dryer drying rice.
The average opacity for one run of 30 minutes was 15.6 percent, with
the average opacity for the highest period of observation during the
run at 28.75 percent. We are soliciting additional emissions test
information and descriptions for emptying and filling activities to
fully understand this process and set, if appropriate, a standard of
performance.
    We request comment on all aspects of the BSER analysis for wire
screen column dryers. We also request additional emission test
information for this subcategory of grain dryer.
c. Temporary Storage Facilities
    Subpart DD does not regulate grain storage units (buildings, bins,
silos). Instead, subpart DD regulates each affected facility (e.g.,
loading and unloading stations, grain dryers, grain handling
operations) at any grain terminal elevator or any grain storage
elevator. Under subpart DD, grain terminal elevators and grain storage
elevators are defined in part by their permanent grain storage
capacity. ``Grain terminal elevator'' means any grain elevator that has
a permanent storage capacity of more than 2.5 million bushels
(excluding elevators located at animal food manufacturers, pet food
manufacturers, cereal manufacturers, breweries and livestock feedlots).
``Grain storage elevator'' means any grain elevator located at any
wheat flour mill, wet corn mill, dry corn mill used for human
consumption, rice mill or soybean extraction plant that has a permanent
grain storage capacity of 1 million bushels.
    Temporary storage facilities have been used by the grain elevator
industry since the early 1990s. They are intended for bulk storage of
grain on a temporary basis, i.e., they are intended to handle
intermittent surges and surpluses and are not used necessarily every
year. Under the U.S. Warehouse Act, TSFs are licensed and are defined
by the following criteria:
     Use of asphalt, concrete or other approved base material.
     Use of rigid self-supporting sidewalls.
     Use of aeration.
     Use of an acceptable covering (e.g., tarp).
    In 2007, the EPA received a letter from the National Grain and Feed
Association requesting clarification about whether a TSF would
constitute ``permanent storage capacity'' as defined in subpart DD for
the purpose of determining applicability under subpart DD. On November
21, 2007, the EPA issued a letter indicating that TSFs should be
included in ``permanent storage capacity'' when determining the
applicability of subpart DD. The EPA conducted additional reviews of
TSFs and decided that changes to the definition of ``permanent storage
capacity'' were more appropriately made as part of this NSPS review.
Consequently, the EPA issued letters in July 2014 to the National Grain
and Feed Association and the National Oilseed Processors Association,
rescinding the November 21, 2007, letter. These letters can be found at
Docket ID Number EPA-HQ-OAR-2010-0706.
    Information collected in responses to surveys the EPA sent to grain
elevators, gathered at site visits, and at industry meetings indicate
that while grain stored in TSFs is kept on a temporary basis, the TSF
structures are generally in place on a long-term basis and not
dismantled, and may be used for multiple crops. Considering the length
of time the structure is in place, the TSF structure then serves the
same purpose as a permanent structure, even though the materials of
construction and storage times are different. Therefore, we are
proposing that the definition of ``permanent storage capacity'' include
TSF capacity. However, we recognize that emissions from TSFs are
significantly different than emissions from permanent structures due to
the differences in grain throughputs. Therefore, we are also proposing
a methodology to prorate the TSF storage capacity for the applicability
determination. Our discussion of this methodology is provided in
section V.B of this preamble.
    We also evaluated BSER for affected facilities associated with
TSFs. Information from site visits and survey responses indicate that
only truck unloading and loading stations and grain handling operations
are used at TSFs. Based on the survey responses and information
provided by the industry, we determined that there are two types of
grain handling and loading/unloading operations associated with TSFs:
(1) Those associated with portable grain handling and loading/unloading
equipment; and (2) those associated with fixed grain handling and
loading/unloading equipment.
    Portable grain handling/loading/unloading equipment include (but
are not limited to) portable augers, portable conveyors and front-end
loaders that are not fixed at any one spot and can be moved around the
site. These pieces of equipment are typically not enclosed due to
potential fine dust explosion risk and are therefore not vented to a
control device. This explosion risk, combined with the portable nature
of the equipment and associated emissions does not permit the capture
and routing of the emissions through a stack for control. As such,
their emissions are fugitive in nature. The EPA does not have any
emission test information on portable grain handling, unloading
stations and loading stations. We also have identified no technically
viable emission control options for portable equipment. We considered
application of mineral oil for dust suppression, but determined in
section A.2.b of this preamble that application of mineral oil was not
an appropriate emission control technique. Consequently, we propose to
determine that BSER for portable grain handling, loading and unloading
equipment associated with TSFs is no control. We request comment on our
proposed determination. We are also soliciting emissions test data for
these sources, as well as information on the types of emission controls
that are feasible and the cost of the controls.
    Fixed grain handling and loading/unloading equipment are
constructed to be stationary and directly connected to the storage
facilities for ease of transferring grain. Fixed equipment can also be
enclosed and emissions can be vented to a control device. Fixed
equipment at TSFs are similar to those associated with permanent
storage

units. To control emissions from affected facilities associated with
TSFs, we identified one regulatory option to be equal to the subpart DD
requirements for affected facilities for permanent storage units. These
requirements include: (1) Meeting a PM emission limit of 0.023 g/dscm
and an opacity limit of 0 percent for process emissions; and (2)
meeting fugitive emission standards of a 5 percent opacity limit for
truck unloading stations, and 0 percent opacity for grain handling
operations. Loading operations from TSFs are typically done with
portable equipment, which we propose the BSER to be no control. No
other regulatory options were identified that are more stringent than
the subpart DD requirements. As discussed in section A.2.b of this
preamble, we evaluated test information submitted with the grain
elevator survey responses and determined that the emission limit that
has been demonstrated to be achievable is the same as the current
subpart DD standards. Controls used at grain elevators are well-
operated fabric filters and no controls more effective than fabric
filters were identified.
    We conducted a BSER analysis for meeting the subpart DD
requirements by evaluating the costs and emission reductions over a 5
year period to be consistent with the economic impacts analysis. We
identified three scenarios at grain elevators that would be affected by
adding TSFs: (1) A greenfield facility that exceeds the subpart DDa
applicability criteria due to the capacity of TSFs; (2) an existing
facility that is below the subpart DDa applicability criteria, but then
adds a TSF and exceeds the criteria; and (3) an existing facility
already subject to subpart DD (because it exceeds the subpart DD
applicability criteria) that then adds a TSF. The additional costs
associated with these scenarios include a shed to limit fugitives from
unloading stations to meet the applicable opacity standard, and in
certain situations, new fabric filters to meet PM limits. In other
situations, the EPA concluded that PM emissions from the affected
facility could be vented to an existing fabric filter at the grain
elevator. Emission reductions were estimated based on routing PM
emissions from grain sent to the TSF (and using truck unloading and
grain handling affected facilities) to a fabric filter.
    We estimated the capital costs to be $1.09 million and the total
annual cost (including testing and monitoring costs) to be $0.616
million. The emission reductions were estimated to be 31 tons of
PM10 per year. Our analysis of BSER is documented in the
memorandum ``Evaluation of Revisions to Grain Elevator Emission
Standards.'' We determined that these costs and emission reductions
were reasonable and BSER is compliant with the proposed subpart DDa PM
and opacity limits for fixed equipment. We request comment on our
determination and additional cost and emissions information on these
systems specific to TSFs.

B. How did the EPA evaluate changes to the methodology for determining
applicability of the grain elevator NSPS?

    Information collected in responses to surveys the EPA sent to grain
elevators shows that TSFs are intended for bulk storage of grain on a
temporary basis, i.e., they are intended to handle intermittent surges
and surpluses and are not used necessarily every year, even though the
structure may be in place for several years. The survey responses show
that, on average, TSFs have one turnover per year. Specifically, they
are filled one time in a year and emptied once each year. Other types
of storage facilities (buildings, bins (not including TSFs) and silos)
have, on average, nine turnovers a year, and throughput a significantly
higher amount of grain in a year than TSFs. The same amount of grain
stored in TSFs could be stored in smaller-sized permanent storage
facilities that are turned over more frequently. Due to the
uncertainties in crop forecasts and fluctuations in crop yields and
economics, TSFs are used rather than constructing other types of
structures that are more costly and may not be warranted in the future.
    Emissions from affected facilities at grain elevators are
proportional to the amount of grain throughput. Consequently, affected
facilities associated with TSFs have significantly less emissions than
affected facilities associated with other types of storage.
    Based on the information collected in the surveys and the EPA's
understanding of the different uses between TSFs and other types of
storage facilities, the EPA has concluded that the capacity of TSFs, as
an indicator of emissions, is not a one-to-one equivalency to the
capacity of other types of grain storage units. As a result, the EPA
analyzed the survey information and developed a method for calculating
an adjusted TSF storage capacity that would be equivalent to the
storage capacity of other types of grain storage units (i.e.,
buildings, silos and bins). This adjusted storage capacity for TSFs
would then be used to calculate ``permanent storage capacity'' by
summing the adjusted TSF capacity with the capacity for all other types
of structures.
    For subpart DDa, the EPA is proposing a method for determining the
adjusted TSF storage capacity for a given grain elevator by: (1)
Establishing the ratio of total annual storage capacity of all other
types of storage facilities (excluding TSFs) to the total grain
throughput for those storage facilities; and (2) applying that ratio to
the total TSF capacity, thereby factoring down the TSF capacity.
    For example, consider a grain elevator has 2,000,000 bushels of
storage capacity in silos and an average annual throughput of
16,000,000 bushels through the silos. The ratio of permanent storage
capacity to throughput is 0.125. If a TSF is constructed with a storage
capacity of 1,000,000 bushels, the TSF capacity would be multiplied by
the 0.125 ratio resulting in an equivalent permanent capacity of
125,000 bushels. The total permanent capacity of the grain elevator
would be 2,125,000 bushels.
    The EPA is proposing that grain elevators with new affected
facilities use this method to calculate ``permanent storage capacity''
for determining applicability of subpart DDa. The EPA is proposing
that, when historical throughput data are available for all storage
facilities, grain elevators would be required to use the historical
data to calculate a site-specific adjusted TSF storage capacity, and
use the following equation to calculate ``permanent storage capacity:''
[GRAPHIC] [TIFF OMITTED] TP09JY14.006

Where:

Ctp = Total permanent storage capacity of all buildings,
bins (including TSFs) and silos used to store grain (bushels).
Cp = Total storage capacity of all buildings, bins
(excluding TSFs) and silos used to store grain (bushels).
Tp = Maximum annual throughput of grain for all
buildings, bins (excluding TSFs) and silos used to store grain
(bushels per year) over the previous 5 years.
Ct = Total storage capacity of all TSFs used to store
grain (bushels).

    For situations where at least one grain storage building, bin or
silo did not exist prior to the date that construction, modification or
reconstruction of the affected facility commenced (i.e., the grain
elevator does not have historical throughput data for the storage
facilities), the EPA is proposing that grain elevators use a default
factor to calculate the adjusted TSF capacity. The following equation
would be used to then calculate the ``permanent storage capacity'':

[GRAPHIC] [TIFF OMITTED] TP09JY14.007

Where:

Ctp = Total permanent storage capacity of all buildings,
bins (including TSFs) and silos used to store grain (bushels).
Cp = Total storage capacity of all buildings, bins
(excluding TSFs) and silos used to store grain (bushels).
Ct = Total storage capacity of all TSFs used to store
grain (bushels).
0.34 = Default ratio of permanent grain storage capacity to annual
throughput

    We request comment on this proposed approach. Refer to the
memorandum, ``Determination of Permanent Storage Capacity Equivalents
for Temporary Storage Facilities'' in the grain elevator docket at EPA-
HQ-OAR-2010-0706 for further details.

C. How did the EPA evaluate the compliance requirements in the grain
elevator NSPS?

    In subpart DDa, we are proposing new monitoring, reporting and
recordkeeping requirements and new provisions for startup, shutdown and
malfunctions.
1. Testing and Monitoring Requirements
    The EPA evaluated the monitoring requirements currently required in
subpart DD to determine if they are adequate for determining
compliance. Currently under subpart DD, grain elevators are required to
conduct an initial PM and opacity performance test but are not required
to perform follow-on testing to demonstrate continuous compliance. In
light of our understanding that equipment need to be periodically
maintained and checked for operational performance to ensure compliance
with the emission standards, the EPA concluded that additional
compliance requirements are needed in the proposed subpart DDa rule. In
subpart DDa, the EPA is proposing to require periodic compliance
testing for affected facilities. We are proposing that PM performance
tests using EPA Method 5 or Method 17 be conducted every 60 months and
opacity tests using Method 9 be conducted annually. We are proposing
that operators perform weekly visual emissions checks on affected
facilities and maintain records of these checks, including any
corrective action taken as a result of visible emissions. The proposed
requirements are expected to ensure that emission control systems are
properly maintained over time, ensure continuous compliance with
standards and improve data accessibility. For fabric filter and
baghouse control devices, we are proposing that affected facilities
perform periodic visual inspections of the inside of the baghouse or
fabric filter at intervals of 6 months. Corrective action must be taken
if the baghouse is in need of repair or replacement.
    We are requesting comment on whether to require bag leak detection
systems (BLDS) at affected facilities controlled with fabric filters
and baghouses. Bag leak detectors are one method that has been used in
other source categories for ensuring proper performance of fabric
filter and baghouses. The EPA has estimated the capital cost of BLDS to
be $24,000 per application. We are soliciting comments on whether BLDS
can be used for affected facilities in this source category, problems
that may occur specific to their use in this source category and the
reasonableness of the cost for this source category.
2. Recordkeeping and Reporting Requirements
    In subpart DDa, we are proposing that the following records be
maintained:
     The total storage capacity (bushels) for each building,
bin (excluding TSFs) and silo used to store grain.
     The storage capacity of each TSF.
     Records quantifying emissions over the applicable
standards for excess emissions events.
     Results of 6 month baghouse and fabric filter inspections,
including any corrective action.
     Weekly visual emissions checks and any corrective action
taken as a result of positive visual emissions checks.
     Results of annual opacity tests.
     The type of grain processed during the performance test at
the affected facility.
    In subpart DDa, we are proposing that the following records be
reported:
     Results of performance tests, including Method 5, 17 and
9.
     Reports required to be submitted by part 60 general
provisions.
    The storage capacities of the various storage units are inputs to
the calculation of equivalent permanent storage capacity, which is an
input to the calculation of equivalent permanent storage capacity for
TSFs. They are necessary to verify compliance with the applicability of
the standard. Records quantifying the emissions for excess emission
events provide the EPA information on the magnitude of the emissions
release.
    As discussed in section V.C.1 of this preamble, we are proposing
that grain elevators conduct PM compliance testing every 60 months and
opacity testing annually and conduct weekly visual inspections of
affected facilities. We are proposing that the Method 5 (or Method 17)
and the Method 9 test results be reported to the EPA. Results of the
visual inspections are proposed to be maintained on site. The type of
grain processed during performance tests allows EPA to better
characterize the emissions measured.
Electronic Reporting Tool
    Through this proposal, the EPA is describing a process to increase
the ease and efficiency of performance test data submittal and improve
data accessibility. Specifically, the EPA is proposing that owners and
operators of grain elevators submit electronic copies of required
performance test reports to the EPA's WebFIRE database. Data will be
entered through an electronic emissions test report structure called
the ERT. The ERT will generate an electronic report which will be
submitted using the CEDRI. The submitted report will be stored in both
EPA's CDX and in the WebFIRE database making access to data very
straightforward and easy. A description of the ERT can be found at
http://www.epa.gov/ttn/chief/ert/index.html and CEDRI can be accessed
through the CDX Web site (www.epa.gov/cdx). A description of the
WebFIRE database is available at: http://cfpub.epa.gov/oarweb/index.cfm?action=fire.main.
    The proposal to submit performance test data electronically to the
EPA applies only to those performance tests conducted using test
methods that will be supported by the ERT. The ERT contains a specific
electronic data entry form for most of the commonly used EPA reference
methods. A listing of the pollutants and test methods supported by the
ERT is available at: http://www.epa.gov/ttn/chief/ert/index.html.
    We believe that industry will benefit from this proposed approach
to electronic data submittal. The EPA believes, through this approach,
industry will save time in the performance test submittal process.
Additionally, the standardized format that the ERT uses allows sources
to create a more complete test report resulting in less time spent on
data backfilling if a source did not know which data elements were
required to be submitted. Also through this proposal, industry would
only need to submit a report once to meet the requirements of the
applicable subpart. This means that the report would be accessible on
the WebFIRE database by any stakeholder who requested a copy from the
facility resulting in a time saving for industry. This also benefits
industry by cutting back on recordkeeping costs as the performance test
reports that are submitted to the EPA using CEDRI are

no longer required to be kept on-site. Thus, staff time needed to
coordinate these records would be reduced.
    Another benefit to industry is that since the EPA will already have
performance test data in hand, fewer or less substantial data
collection requests in conjunction with prospective required technology
reviews will be needed. This would result in a decrease in staff time
needed to respond to data collection requests.
    State, local and tribal agencies will also benefit from more
streamlined and accurate review of electronic data submitted to them.
For example, the ERT would allow for an electronic review process
rather than a manual data assessment; thus making review and evaluation
of the source-provided data and calculations easier and more efficient.
In addition, the public stands to benefit from electronic reporting of
emissions data because the electronic data will be easier for the
public to access and it will be available shortly after it is submitted
in the system. For example, the WebFIRE database is easily accessible
and provides a user friendly interface for any stakeholder to find and
review any report submitted.
    One major shared advantage of the proposed submittal of performance
test data through the ERT is a standardized method to compile and store
much of the documentation required to be reported by this rule. The ERT
clearly states what testing information would be required by the test
method and has the ability to house additional data elements required
by a delegated authority. Another important proposed benefit of
submitting these data to the EPA at the time the source test is
conducted is that it should substantially reduce the effort involved in
data collection activities in the future. Having these data allows the
EPA to develop improved emission factors, make fewer information
requests and promulgate better regulations.
    In addition, the EPA must have performance test data to conduct
effective reviews of CAA sections 112 and 129 standards, as well as for
many other purposes including compliance determinations, emission
factor development and annual emission rate determinations. In
conducting these required reviews, the EPA has found it ineffective and
time consuming, not only for us, but also for regulatory agencies and
source owners and operators, to locate, collect and submit performance
test data because of varied locations for data storage and varied data
storage methods. In recent years, however, stack testing firms have
typically collected performance test data in electronic format, making
it possible to move to an electronic data submittal system that would
increase the ease and efficiency of data submittal and improve data
accessibility.
    A common complaint heard from industry and regulators is that
emission factors are outdated or not representative of a particular
source category. With timely receipt and incorporation of data from
performance tests, the EPA would be able to ensure that emission
factors, when updated, represent the most current range of operational
practices. Finally, another benefit of the proposed data submittal to
WebFIRE electronically is that these data would greatly improve the
overall quality of existing and new emissions factors by supplementing
the pool of emissions test data for establishing emissions factors
    In summary, in addition to supporting regulation development,
control strategy development and other air pollution control
activities, having an electronic database populated with performance
test data would save industry, state, local, tribal agencies and the
EPA significant time, money and effort while also improving the quality
of emission inventories and, as a result, air quality regulations.
3. Startup, Shutdown and Malfunction Provisions
    The general provisions in 40 CFR part 60 provide that emissions in
excess of the level of the applicable emissions limit during periods of
SSM shall not be considered a violation of the applicable emission
limit unless otherwise specified in the applicable standard (see 40 CFR
60.8(c)). In its 2008 decision in Sierra Club v. EPA, 551 F.3d 1019
(D.C. Cir. 2008), 130 S. Ct. 1735 (U.S. 2010), the U.S. Court of
Appeals for the District of Columbia Circuit vacated portions of two
provisions in the EPA's CAA section 112 regulations governing the
emissions of HAP during periods of SSM. Specifically, the Court vacated
the SSM exemption contained in 40 CFR 63.6(f)(1) and 40 CFR 63.6(h)(1),
holding that under section 302(k) of the CAA, emissions standards or
limitations must be continuous in nature and that the SSM exemption
violates the CAA's requirement that some section 112 standards apply
continuously. We are proposing the elimination of the SSM exemption in
this rule. Consistent with Sierra Club v. EPA, the EPA is proposing
standards in this rule that apply at all times, including periods of
startup or shutdown. The EPA has attempted to ensure that the
provisions we are proposing to eliminate are inappropriate, unnecessary
or redundant in the absence of the SSM exemption. We are specifically
seeking comment on whether we have successfully done so.
a. Periods of Startup and Shutdown
    In proposing the standards in this rule, the EPA has taken into
account startup and shutdown periods and does not have any information
that indicates that emissions during startup and shutdown are different
from emissions during steady-state operation; therefore, the EPA
proposes to apply the proposed standards during all periods of
operation.
    If you believe that the EPA's conclusion is incorrect or that the
EPA has failed to consider any relevant information on this point, we
encourage you to submit comments, including test data during periods of
startup and shutdown. In particular, we note that the general
provisions in part 60 require facilities to keep records of the
occurrence and duration of any SSM (40 CFR 60.7(b)) and either report
to the EPA any period of excess emissions that occurs during periods of
SSM (40 CFR 60.7(c)(2)) or report that no excess emissions occurred (40
CFR 60.7(c)(4)). Thus, any comments that contend that sources cannot
meet the proposed standard during startup and shutdown periods should
provide these data and other specifics supporting their claim.
b. Periods of Malfunction
    Periods of startup, normal operations and shutdown are all
predictable and routine aspects of a source's operations. However, by
contrast, malfunction is defined as ``any sudden, infrequent, and not
reasonably preventable failure of air pollution control equipment,
process equipment, or a process to operate in a normal or usual manner.
Failures that are caused in part by poor maintenance or careless
operation are not malfunctions.'' (40 CFR 60.2). The EPA has determined
that section 111 does not require that emissions that occur during
periods of malfunction be factored into development of CAA section 111
standards. Nothing in CAA section 111 or in case law requires that the
EPA anticipate and account for the innumerable types of potential
malfunction events in setting emission standards. CAA section 111
provides that the EPA set standards of performance which reflect the
degree of emission limitation achievable through ''the application of
the best system of emission reduction'' that the EPA determines is
adequately demonstrated. A malfunction is a failure of the source to
perform in a ``normal or usual manner'' and no statutory language

compels EPA to consider such events in setting standards based on the
``best system of emission reduction.'' The ''application of the best
system of emission reduction'' is more appropriately understood to
include operating units in such a way as to avoid malfunctions.
    Further, accounting for malfunctions in setting emission standards
would be difficult, if not impossible, given the myriad different types
of malfunctions that can occur across all sources in the category and
given the difficulties associated with predicting or accounting for the
frequency, degree and duration of various malfunctions that might
occur. As such, the performance of units that are malfunctioning is not
``reasonably'' foreseeable. See, e.g., Sierra Club v. EPA, 167 F. 3d
658, 662 (D.C. Cir. 1999) (``The EPA typically has wide latitude in
determining the extent of data-gathering necessary to solve a problem.
We generally defer to an agency's decision to proceed on the basis of
imperfect scientific information, rather than to `invest the resources
to conduct the perfect study.'''). See also, Weyerhaeuser v. Costle,
590 F.2d 1011, 1058 (D.C. Cir. 1978) (``In the nature of things, no
general limit, individual permit, or even any upset provision can
anticipate all upset situations. After a certain point, the
transgression of regulatory limits caused by `uncontrollable acts of
third parties,' such as strikes, sabotage, operator intoxication or
insanity, and a variety of other eventualities, must be a matter for
the administrative exercise of case-by-case enforcement discretion, not
for specification in advance by regulation.''). In addition, emissions
during a malfunction event can be significantly higher than emissions
at any other time of source operation and thus accounting for
malfunctions could lead to standards that are significantly less
stringent than levels that are achieved by a well-performing non-
malfunctioning source. It is reasonable to interpret section 111 to
avoid such a result. The EPA's approach to malfunctions is consistent
with section 111 and is a reasonable interpretation of the statute.
    In the event that a source fails to comply with the applicable CAA
section 111 standards as a result of a malfunction event, the EPA would
determine an appropriate response based on, among other things, the
good faith efforts of the source to minimize emissions during
malfunction periods, including preventative and corrective actions, as
well as root cause analyses to ascertain and rectify excess emissions.
The EPA would also consider whether the source's failure to comply with
the CAA section 111 standards was, in fact, ``sudden, infrequent, not
reasonably preventable'' and was not instead ``caused in part by poor
maintenance or careless operation.'' 40 CFR 60.2 (definition of
malfunction).
    Further, to the extent the EPA files an enforcement action against
a source for violation of an emission standard, the source can raise
any and all defenses in that enforcement action and the federal
district court will determine what, if any, relief is appropriate. The
same is true for citizen enforcement actions. Similarly, the presiding
officer in an administrative proceeding can consider any defense raised
and determine whether administrative penalties are appropriate.
    In several prior rules, the EPA had included an affirmative defense
to civil penalties for violations caused by malfunctions in an effort
to create a system that incorporates some flexibility, recognizing that
there is a tension, inherent in many types of air regulation, between
ensuring adequate compliance and simultaneously recognizing that
despite the most diligent of efforts, emission standards may be
violated under circumstances entirely beyond the control of the source.
Although the EPA recognized that its case-by-case enforcement
discretion provides flexibility in these circumstances, it included the
affirmative defense language to provide a more formalized approach and
more regulatory clarity. See Weyerhaeuser Co. v. Costle, 590 F.2d 1011,
1057-58 (D.C. Cir. 1978) (holding that an informal case-by-case
enforcement discretion approach is adequate); but see Marathon Oil Co.
v. EPA, 564 F.2d 1253, 1272-73 (9th Cir. 1977) (requiring a more
formalized approach to consideration of ``upsets beyond the control of
the permit holder.''). Under the EPA's regulatory affirmative defense
provisions, if a source could demonstrate in a judicial or
administrative proceeding that it had met the requirements of the
affirmative defense in the regulation, civil penalties would not be
assessed. Recently, the United States Court of Appeals for the District
of Columbia Circuit vacated such an affirmative defense in one of the
EPA's Section 112(d) regulations. NRDC v. EPA, No. 10-1371 (D.C. Cir.
April 18, 2014) 2014 U.S. App. LEXIS 7281 (vacating affirmative defense
provisions in Section 112(d) rule establishing emission standards for
Portland cement kilns). The court found that the EPA lacked authority
to establish an affirmative defense for private civil suits and held
that under the CAA, the authority to determine civil penalty amounts
lies exclusively with the courts, not the EPA. Specifically, the Court
found: ``As the language of the statute makes clear, the courts
determine, on a case-by-case basis, whether civil penalties are
`appropriate.''' See NRDC, 2014 U.S. App. LEXIS 7281 at *21 (``[U]nder
this statute, deciding whether penalties are `appropriate' in a given
private civil suit is a job for the courts, not EPA.'').\4\ In light of
NRDC, the EPA is not including a regulatory affirmative defense
provision in this rulemaking. As explained above, if a source is unable
to comply with emissions standards as a result of a malfunction, the
EPA may use its case-by-case enforcement discretion to provide
flexibility, as appropriate. Further, as the DC Circuit recognized, in
an EPA or citizen enforcement action, the court has the discretion to
consider any defense raised and determine whether penalties are
appropriate. Cf. NRDC, 2014 U.S. App. LEXIS 7281 at *24. (arguments
that violations were caused by unavoidable technology failure can be
made to the courts in future civil cases when the issue arises). The
same logic applies to EPA administrative enforcement actions.
---------------------------------------------------------------------------

    \4\ The court's reasoning in NRDC focuses on civil judicial
actions. The Court noted that ``EPA's ability to determine whether
penalties should be assessed for Clean Air Act violations extends
only to administrative penalties, not to civil penalties imposed by
a court.'' Id.
---------------------------------------------------------------------------

D. How did the EPA evaluate additional changes for the grain elevator
NSPS?

    As summarized in section IV of this preamble, we are proposing
revisions to three provisions in subpart DD to clarify applicability of
the standards for grain elevators under subpart DD. These proposed
revisions are intended to keep the meaning and intent of the
definitions as originally promulgated while making the definitions
applicable to the changes in the industry since the last review of
subpart DD in 1984. The same clarifications are being proposed in
subpart DDa. These proposed clarifications would apply to all affected
facilities that commence construction, modification or reconstruction
after August 3, 1978 (i.e., all affected facilities under both subpart
DD and proposed subpart DDa). None of these clarifications would
increase the cost of the rule or result in a change in PM emissions.
1. Revision to the Definition of ``Grain Unloading Station''
    We are proposing to revise the definition of ``grain unloading
station''

to clarify which components of the unloading station are part of the
affected facility.
    The background information document (BID) (EP-450/2-77-001a) for
the original grain elevator NSPS does not define each piece of
equipment included in the term ``grain unloading station''. However,
throughout the BID, in the description of the grain elevator emission
sources and processes in chapter 2, and in Figures 2-2 through 2-4, and
Figures 4-1 through 4-4, the unloading process is described and shown
to terminate at a hopper. Grain is then transported from the hopper via
a conveyor to a bucket elevator. Based on the information in the BID,
we concluded that at the time the NSPS was proposed and later
finalized, the standard practice of the grain elevator industry was to
have the hopper be the ending piece of equipment at the truck, rail,
and barge/ship unloading stations. We received information from the
grain elevator industry that since the last review of subpart DD in
1984, some grain unloading stations no longer use a hopper as the end
of the unloading station, and instead use another storage unit, or
transfer grain directly onto the grain conveyor. Industry white papers
that serve as the basis for this conclusion can be found at Docket ID
Number EPA-HQ-OAR-2010-0706. Because of these changes, we are proposing
to better define the outer boundaries of a ``grain unloading station''
where the termination point of the unloading operation is not a hopper.
The NSPS and the BID also do not specify the types of equipment
included in grain unloading stations, resulting in the boundaries of
the ``unloading station'' affected facilities being unclear to the
regulated community. We received input from the grain industry on the
types of equipment that are included in the ``grain unloading
station''. Consequently, we are also proposing to clarify in the
definition all the types of equipment involved in unloading, up to the
point that the grain is transferred to either storage or to grain
handling operations. Industry white papers that serve as the basis for
this conclusion can be found at Docket ID Number EPA-HQ-OAR-2010-0706.
    We are therefore proposing revisions to the definition of ``grain
unloading station'' to clarify that a ``grain unloading station''
encompasses the portion of a grain elevator where the grain is
transferred from a truck, railcar, barge or ship to a receiving hopper,
or to the grain handling equipment that connects the unloading station
to the rest of the grain elevator. This definition includes all of the
equipment, support structures and associated dust control equipment and
aspiration systems required to operate or are otherwise connected to
the grain unloading station. We are requesting comment on our
interpretation of the intent of the original NSPS definition of ``grain
unloading station'' and our proposed revisions to the definition.
2. Revision to Definition of ``Grain Loading Station''
    We are proposing to revise the definition of ``grain loading
station'' to clarify all the types of equipment involved in unloading,
up to the point that the grain is transferred to either storage or to
grain handling operations. As discussed in section V.D.1 of this
preamble, the background information document (BID) (EP-450/2-77-001a)
for the original grain elevator NSPS does not define each piece of
equipment included in the term ``grain loading station''. Because the
NSPS and the BID do not specify the types of equipment included in
grain unloading stations, the boundaries of the ``grain loading
station'' affected facilities are unclear to the regulated community.
We also received input from the grain industry on the types of
equipment that are included in the ``grain loading station''.
Consequently, we are proposing to clarify in the definition all the
types of equipment involved in loading. Industry white papers that
serve as the basis for this conclusion can be found at Docket ID Number
EPA-HQ-OAR-2010-0706. The proposed revision also maintains consistency
with the proposed revision to the definition of ``grain unloading
station''. These changes are supported by representatives of the grain
elevator industry in their white papers.
3. Revision to the Operating Requirements for Barge and Ship Unloading
Stations
    Current Sec.  60.302(d)(1) requires that the unloading leg be
enclosed from the top, including the receiving hopper, to the center
line of the bottom pulley. However, not all barge and ship unloading
stations currently use a hopper. More recently, new technologies have
been developed such that a hopper is not required. We are proposing to
revise Sec.  60.302(d)(1) to clarify the provision for affected barge
and ship unloading stations for which aspiration of the casing provides
dust control at the boot of the conveyor and a receiving hopper is not
used. The proposed revision clarifies that, in such cases, the
unloading leg is required to be enclosed from the top to the center
line of the bottom pulley and ventilation to a control device is
required to be maintained on both sides of the leg.

VI. Summary of Cost, Environmental, Energy and Economic Impacts of
These Proposed Standards

    In setting standards, the CAA requires us to consider emission
control approaches, taking into account the estimated costs and
emission reductions, as well as impacts on energy, solid waste and
other effects.

A. What are the impacts for subpart DDa?

    The cost, environmental and economic impacts presented in this
section are expressed as incremental differences between the impacts of
grain elevators complying with the proposed subpart DDa and the current
NSPS requirements of subpart DD. The impacts are presented for future
grain elevators that are projected to commence construction,
reconstruction or modification over the 5 years following proposal of
the revised NSPS. Costs are based on 2012 dollars. The analyses and the
documents referenced below can be found at Docket ID Number EPA-HQ-OAR-
2010-0706.
    In order to estimate the incremental impacts of the proposed
subpart DDa requirements, we first identified the potential scenarios
where grain elevators may be constructed, reconstructed or modified and
subject to subpart DDa. Seven different scenarios were identified and
are summarized in Table 4 of this preamble.

   Table 4--Scenarios Used To Estimate Impacts of Proposed Subpart DDa
                              Requirements
------------------------------------------------------------------------
             Scenario                            Description
------------------------------------------------------------------------
1a................................  Greenfield grain elevator with
                                     capacity (based on permanent
                                     storage only) > DDa cutoffs.
1b................................  Greenfield grain elevator with
                                     capacity > DDa cutoffs due to TSF
                                     capacity.
2.................................  Existing grain elevator with
                                     capacity < DDa cutoffs, but then
                                     adds TSF capacity and exceeds
                                     cutoffs.
3.................................  Existing grain elevator with
                                     capacity < DDa cutoffs, but then
                                     adds permanent storage capacity and
                                     exceeds cutoffs.

4.................................  Existing grain elevator with
                                     capacity > DDa cutoffs, but then
                                     adds TSF capacity.