National Emission Standards for Hazardous Air Pollutants: Plywood and Composite Wood Products, 44012-44036 [05-14532]

Agencies

• ENVIRONMENTAL PROTECTION AGENCY

[Federal Register Volume 70, Number 145 (Friday, July 29, 2005)]
[Proposed Rules]
[Pages 44012-44036]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-14532]



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Part IV





Environmental Protection Agency





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40 CFR Part 63



National Emission Standards for Hazardous Air Pollutants: Plywood and 
Composite Wood Products; Proposed Rule

Federal Register / Vol. 70, No. 145 / Friday, July 29, 2005 / 
Proposed Rules

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 63

[OAR-2003-0048; FRL-7947-8]
RIN 2060-AM78


National Emission Standards for Hazardous Air Pollutants: Plywood 
and Composite Wood Products

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule; amendments.

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SUMMARY: On July 30, 2004, EPA promulgated national emission standards 
for hazardous air pollutants (NESHAP) for the plywood and composite 
wood products (PCWP) source category. Stakeholders expressed concern 
with some of the final rule requirements, including definitions; the 
emissions testing procedures required for facilities demonstrating 
eligibility for the low-risk subcategory; stack height calculations to 
be used in low-risk subcategory eligibility demonstrations; and 
permitting and timing issues associated with the low-risk subcategory 
eligibility demonstrations. In this action, EPA proposes amendments to 
the final PCWP NESHAP to address these issues and to correct any other 
inconsistencies that were discovered during the review process. This 
action also clarifies some common applicability questions. We are 
seeking comment on the provisions of the final PCWP rule outlined in 
this action. We are not requesting comments addressing other provisions 
of the final PCWP rule.

DATES: Comments. Comments must be received on or before September 12, 
2005.
    Public Hearing. If anyone contacts EPA requesting to speak at a 
public hearing by August 8, 2005, a public hearing will be held on 
August 15, 2005. For further information on the public hearing and 
requests to speak, see the ADDRESSES section of this preamble.

ADDRESSES: Comments. Submit your comments, identified by Docket ID No. 
OAR-2003-0048 (Legacy Docket ID No. A-98-44) by one of the following 
methods:
     Federal eRulemaking Portal: https://www.regulations.gov. 
Follow the on-line instructions for submitting comments.
     Agency Web site: https://www.epa.gov/edocket. EDOCKET, 
EPA's electronic public docket and comment system, is EPA's preferred 
method for receiving comments. Follow the on-line instructions for 
submitting comments.
     E-mail: a-and-r-docket@epa.gov.
     Fax: (202) 566-1741.
     Mail: Air and Radiation Docket and Information Center, 
EPA, Mailcode: 6102T, 1200 Pennsylvania Avenue, NW., Washington, DC 
20460.
     Hand Delivery: Air and Radiation Docket and Information 
Center, EPA, Room B102, 1301 Constitution Avenue, NW., Washington, DC. 
Such deliveries are only accepted during the Docket's normal hours of 
operation, and special arrangements should be made for deliveries of 
boxed information.
    Instructions. Direct your comments to Docket ID No. OAR-2003-0048 
(Legacy Docket ID No. A-98-44). EPA's policy is that all comments 
received will be included in the public docket without change and may 
be made available online at https://www.epa.gov/edocket, including any 
personal information provided, unless the comment includes information 
claimed to be Confidential Business Information (CBI) or other 
information whose disclosure is restricted by statute. Do not submit 
information that you consider to be CBI or otherwise protected through 
EDOCKET, regulations.gov, or e-mail. EPA EDOCKET and the Federal 
regulations.gov websites are ``anonymous access'' systems, which means 
EPA will not know your identity or contact information unless you 
provide it in the body of your comment. If you send an e-mail comment 
directly to EPA without going through EDOCKET or regulations.gov, your 
e-mail address will be automatically captured and included as part of 
the comment that is placed in the public docket and made available on 
the Internet. If you submit an electronic comment, EPA recommends that 
you include your name and other contact information in the body of your 
comment and with any disk or CD ROM you submit. If EPA cannot read your 
comment due to technical difficulties and cannot contact you for 
clarification, EPA may not be able to consider your comment. Electronic 
files should avoid the use of special characters, any form of 
encryption, and be free of any defects or viruses.
    Public Hearing. If a public hearing is held, it will be held on 
August 15, 2005 at the EPA facility, Research Triangle Park, NC or an 
alternative site nearby. Persons interested in attending the hearing or 
wishing to present oral testimony should notify Ms. Mary Tom Kissell at 
least 2 days in advance of the public hearing (see FOR FURTHER 
INFORMATION CONTACT section of this preamble). The public hearing will 
provide interested parties the opportunity to present data, views, or 
arguments concerning this proposed rule.
    Docket. EPA has established an official public docket for today's 
proposed amendments, including both Docket ID No. OAR-2003-0048 and 
Legacy Docket ID No. A-98-44. The official public docket consists of 
the documents specifically referenced in today's proposed amendments, 
any public comments received, and other information related to the 
proposed amendments. All items may not be listed under both docket 
numbers, so interested parties should inspect both docket numbers to 
ensure that they have received all materials relevant to today's 
proposed amendments. Although listed in the index, some information is 
not publicly available, i.e., CBI or other information whose disclosure 
is restricted by statute. Certain other material, such as copyrighted 
material, is not placed on the Internet and will be publicly available 
only in hard copy form. Publicly available docket materials are 
available either electronically in EDOCKET or in hard copy at the Air 
and Radiation Docket and Information Center, EPA, Room B102, 1301 
Constitution Avenue, NW., Washington, DC. The Public Reading Room is 
open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding 
legal holidays. The telephone number for the Public Reading Room is 
(202) 566-1744, and the telephone number for the Air and Radiation 
Docket and Information Center is (202) 566-1742.

FOR FURTHER INFORMATION CONTACT: For general and technical information, 
and questions about the public hearing, contact Ms. Mary Tom Kissell, 
Waste and Chemical Processes Group, Emission Standards Division, 
Mailcode: C439-03, EPA, Research Triangle Park, NC 27711; telephone 
number: (919) 541-4516; fax number: (919) 541-0246; e-mail address: 
kissell.mary@epa.gov.

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

I. General Information
    A. Do these proposed amendments apply to me?
    B. How do I submit CBI?
    C. How do I obtain a copy of this document and other related 
information?
II. Background
III. Summary of the Proposed Amendments
IV. Rationale for the Proposed Amendments
    A. Amendments to Subpart DDDD of 40 CFR Part 63
    B. Amendments to Appendix B to Subpart DDDD of 40 CFR Part 63
    C. Other Amendments to the Rule
V. Additional Clarifications
    A. Integrated Drying Systems Where Combustion Units That Heat 
the Dryers Are Used as Control Devices
    B. Applicability of the PCWP Rule to Hot Pressing of Veneers 
onto a Substrate

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VI. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review
    B. Paperwork Reduction Act
    C. Regulatory Flexibility Act
    D. Unfunded Mandates Reform Act
    E. Executive Order 13132: Federalism
    F. Executive Order 13175: Consultation and Coordination With 
Indian Tribal Governments
    G. Executive Order 13045: Protection of Children from 
Environmental Health & Safety Risks
    H. Executive Order 13211: Actions that Significantly Affect 
Energy Supply, Distribution, or Use
    I. National Technology Transfer and Advancement Act

I. General Information

A. Do these proposed amendments apply to me?

    Categories and entities potentially affected by today's proposed 
amendments include:

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             Category                SIC code \a\   NAICS code \b\         Examples of regulated entities
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Industry..........................            2421          321999  Sawmills with lumber kilns.
                                              2435          321211  Hardwood plywood and veneer plants.
                                              2436          321212  Softwood plywood and veneer plants.
                                              2493          321219  Reconstituted wood products plants
                                                                     (particleboard, medium density fiberboard,
                                                                     hardboard, fiberboard, and oriented
                                                                     strandboard plants).
                                              2439          321213  Structural wood members, not elsewhere
                                                                     classified (engineered wood products
                                                                     plants).
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\a\ Standard Industrial Classification.
\b\ North American Industrial Classification System.

    This table is not intended to be exhaustive, but rather provides a 
guide for readers regarding entities likely to be affected by today's 
proposed amendments. To determine whether your facility is affected by 
today's proposed amendments, you should examine the applicability 
criteria in Sec.  63.2231 of the final rule. If you have questions 
regarding the applicability of today's proposed amendments to a 
particular entity, consult Ms. Mary Tom Kissell listed in the preceding 
FOR FURTHER INFORMATION CONTACT section.

B. How do I submit CBI?

    Do not submit this information to EPA through EDOCKET, 
regulations.gov, or e-mail. Clearly mark the part or all of the 
information that you claim to be CBI. For CBI in a disk or CD ROM that 
you mail to EPA, mark the outside of the disk or CD ROM as CBI and then 
identify electronically within the disk or CD ROM the specific 
information that is claimed as CBI. In addition to one complete version 
of the comment that includes information claimed as CBI, a copy of the 
comment that does not contain the information claimed as CBI must be 
submitted for inclusion in the public docket. Information so marked 
will not be disclosed except in accordance with procedures set forth in 
40 CFR part 2.

C. How do I obtain a copy of this document and other related 
information?

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

II. Background

    On July 30, 2004, we promulgated NESHAP for Plywood and Composite 
Wood Products Manufacturing as subpart DDDD in 40 CFR part 63 (69 FR 
45944). Subpart DDDD contains two appendices: an alternative procedure 
for determining capture efficiency from hot press enclosures (appendix 
A to subpart DDDD of 40 CFR part 63), and methodology and criteria for 
demonstrating that an affected source is part of the low-risk 
subcategory of PCWP manufacturing affected sources (appendix B to 
subpart DDDD of 40 CFR part 63). Today we are proposing corrections and 
clarifications to subpart DDDD and both of the appendices to subpart 
DDDD. For subpart DDDD, we are proposing several changes to ensure that 
the rule is implemented as intended: (1) Amend the sampling location 
for coupled control devices; (2) amend language to clarify rule 
applicability during unscheduled startups and shutdowns; (3) add 
language to clarify rule applicability for affected sources with no 
process units subject to compliance options or work practice 
requirements; and (4) amend selected definitions. A minor numbering 
error is proposed to be corrected in appendix A to subpart DDDD. The 
majority of the amendments discussed in today's action are being 
proposed for appendix B to subpart DDDD. We are proposing amendments to 
appendix B to subpart DDDD to reduce the number of emissions tests 
required while ensuring that emissions from all PCWP process units are 
considered when demonstrating eligibility for the low-risk subcategory. 
For emission points that would still require emission tests, we are 
proposing that the emissions tests may be conducted after the low-risk 
demonstration is submitted. We are also proposing that physical changes 
necessary to ensure low risk may be completed after the low-risk 
demonstration is submitted. We are proposing to clarify the calculation 
of average stack height and some timing issues related to low-risk 
demonstrations, including the deadline for submitting low-risk 
demonstrations. Furthermore, we are proposing to amend subpart A to 40 
CFR part 63 and subpart DDDD of 40 CFR part 63 and appendix B to 
subpart DDDD to allow use of a new hazardous air pollutants (HAP) test 
method developed by the National Council of the Paper Industry for Air 
and Stream Improvement (NCASI).
    Following promulgation of the PCWP rule, the Administrator received 
a petition for reconsideration filed by the Natural Resources Defense 
Council (NRDC) and Environmental Integrity Project (EIP) pursuant to 
section 307(d)(7)(B) of the Clean Air Act (CAA).\1\ The petition 
requested

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reconsideration of nine aspects of the final rule: (1) Risk assessment 
methodology; (2) background pollution and co-located emission sources; 
(3) dose-response value used for formaldehyde; (4) costs and benefits 
of the low-risk subcategory; (5) ecological risk; (6) legal basis for 
the risk-based approach; (7) maximum achievable control technology 
(MACT) compliance date for affected sources previously qualifying for 
the low-risk subcategory; (8) startup, shutdown, and malfunction (SSM) 
provisions; and (9) title V implementation mechanism for the risk-based 
approach. With the exception of the petitioners' issue with the SSM 
provisions in subpart DDDD of 40 CFR part 63, all of the petitioners' 
issues relate to the risk-based approach adopted in the final rule. The 
issues raised in the petition for reconsideration are broader in scope 
than the issues addressed in today's proposed amendments. We have 
published a separate notice of reconsideration to initiate rulemaking 
by requesting comments on the issues in the petition for 
reconsideration, including the full content of appendix B to subpart 
DDDD. We intend to address all comments received on the notice of 
reconsideration and today's proposed amendments by the time we finalize 
the amendments.
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    \1\ In addition to the petition for reconsideration, four 
petitions for judicial review of the final PCWP rule were filed with 
the U.S. Court of Appeals for the District of Columbia by NRDC and 
Sierra Club (No. 04-1323, D.C. Cir.), EIP (No. 04-1235, D.C. Cir.), 
Louisiana-Pacific Corporation (No. 04-1328, D.C. Cir.), and Norbord 
Incorporated (No. 04-1329, D.C. Cir.). The four cases have been 
consolidated. In addition, the following parties have filed as 
interveners: American Forest and Paper Association (AF&PA), Hood 
Industries, Scotch Plywood, Coastal Lumber Company, Composite Panel 
Association, APA-The Engineered Wood Association, American Furniture 
Manufacturers Association, NRDC, Sierra Club, and EIP. Finally, the 
Formaldehyde Council, Inc. and the State and Territorial Air 
Pollution Program Administrators and Association of Local Air 
Pollution Control Officials (STAPPA/ALAPCO) are participating in the 
litigation as amicus curiae.
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III. Summary of the Proposed Amendments

    Today's proposed amendments to subpart DDDD of 40 CFR part 63 and 
its appendices are summarized in table 1 of this preamble.

              Table 1.--Summary of the Proposed Amendments
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           Citation                              Change
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Sec.  Sec.   63.2232(b) and    Amend definition of ``affected source''
 63.2292.                       to include the combustion unit exhaust
                                streams used to direct-fire process
                                units.
Sec.   63.2250(a)............  Amend the rule's language to clarify the
                                applicability of the compliance options
                                and operating requirements during
                                unscheduled startups and shutdowns.
Sec.   63.2252...............  Add a section to clarify that process
                                units that are not subject to compliance
                                options or work practice requirements
                                (e.g., lumber kilns) are excluded from
                                the performance testing, monitoring, SSM
                                plan, recordkeeping, and reporting
                                requirements, except for the initial
                                notification requirements.
Sec.   63.2262(d)(1).........  Allow testing between a wet control
                                device followed by a HAP control device.
Sec.   63.2269(c)............  Amend section to correct numbering of
                                cross-referenced paragraphs.
Sec.   63.2292...............  Amend the definition of ``tube dryer'' to
                                clarify that heat is applied in the
                                dryer to reduce the moisture content of
                                the wood fibers or particles. Amend the
                                definition of ``plywood and composite
                                wood products manufacturing facility''
                                to clarify the products covered by
                                subpart DDDD. Amend the definition of
                                ``plywood'' to clarify that plywood
                                products may be curved or flat. Add
                                definitions of ``molded particleboard''
                                and ``engineered wood product.''
Sec.   63.2292 and Appendix    Move the definition of ``direct-fired
 B, section 15.                 process unit'' from section 15 of
                                appendix B to subpart DDDD to Sec.
                                63.2292 of subpart DDDD.
Table 4, Lines 6-8...........  Allow NCASI Method ISS/FP-A105.01 for
                                testing of formaldehyde, methanol, and
                                total HAP.
Table 4, line 10 and Appendix  Clarify that measured emissions divided
 B, Table 2, line 10.           by the capture efficiency provides the
                                emission rate for unenclosed and
                                uncontrolled presses and board coolers.
Appendix A, section 10.......  Correct misnumbering of sections 10.4 and
                                10.5.
Appendix B, sections 4(a),     Amend terminology to refer to ``emission
 5(a), 6(a) through (c), and    point'' instead of ``process unit.''
 Equations 1 and 2.
Appendix B, section 5(a) and   Add Table 2A and conforming text
 Table 2A.                      specifying which process units must be
                                tested and which process units may use
                                emission factors or engineering
                                estimates to estimate emissions.
Appendix B, section 5(f)(1)..  Add reference to NCASI IM/CAN/WP 99.02,
                                EPA Method 18, and NCASI Method ISS/FP-
                                A105.01.
Appendix B, section 5(f)(2)..  Allow use of other EPA Method 29
                                laboratory analysis procedures with
                                detection limits equal to or lower than
                                atomic absorption spectroscopy (AAS)
                                when claiming zero for non-detect HAP
                                metals measurements.
Appendix B, section 5(i).....  Allow use of previous emissions test
                                results (e.g., NCASI IM/CAN/WP 99.01).
Appendix B, section 5(j).....  Allow only one of multiple similar
                                process units at a plant site to be
                                tested (e.g., one of three veneer dryers
                                at a plant).
Appendix B, section 5(k).....  Specify requirements for developing
                                emissions estimates according to Table
                                2A.
Appendix B, section 6(a).....  Amend to clarify that section 6(a)
                                applies when emissions estimation or
                                testing is performed.
Appendix B, section 6(a).....  Add equations for calculation of
                                carcinogen and non-carcinogen weighted-
                                average stack height.
Appendix B, sections 6(b),     Amend to clarify that weighted-average
 6(c), 8(b)(1), and 8(b)(3).    stack height calculations must be used.
Appendix B, section 7(a).....  Amend to correct Web site address
Appendix B, section 8(a)(3)..  Require submittal of emissions estimate
                                calculations with low-risk
                                demonstrations.
Appendix B, section 10(a)....  Amend date for existing sources to
                                conduct emissions tests and to submit
                                demonstrations of eligibility for the
                                low-risk subcategory.
Appendix B, section 10(c)....  Amend date for new sources to conduct
                                emissions tests and to submit
                                demonstrations of eligibility for the
                                low-risk subcategory.
Appendix B, section 11(b)....  Amend to clarify that the parameters that
                                defined the affected source as part of
                                the low-risk subcategory must be
                                submitted for incorporation into its
                                title V permit, as opposed to having the
                                permit revised before the MACT
                                compliance date.
Appendix B, section 15.......  Add definitions of various process units
                                not defined in subpart DDDD and move
                                definition of ``direct-fired process
                                unit'' to Sec.   63.2292.

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Appendix B, Table 2..........  Renumber as Table 2B. Replace footnote 1
                                related to benzene and acrolein testing
                                with a footnote noting that direct-fired
                                process units fired with only natural
                                gas or propane are exempt from HAP
                                metals testing.
Appendix B, Table 2, line 5..  Allow NCASI Method ISS/FP-A105.01 for
                                testing of acetaldehyde, acrolein,
                                formaldehyde, and phenol.
Appendix B, Table 2, line 6..  Allow use of NCASI IM/CAN/WP 99.02 or EPA
                                Method 18 (40 CFR part 60, appendix A)
                                for benzene testing.
Appendix B, Table 3..........  Change column heading to ``distance to
                                property boundary.''
Appendix B, Tables 3 and 4...  Delete footnote regarding units of
                                measure.
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IV. Rationale for the Proposed Amendments

A. Amendments to Subpart DDDD of 40 CFR Part 63

1. Sampling Location
    It is common in the PCWP industry for multiple add-on control 
devices to be used in series (e.g., a wet electrostatic precipitator 
(WESP) for control of particulate matter (PM) followed by a thermal 
oxidizer for control of organic HAP and volatile organic compounds 
(VOC)). Some types of PM control devices have no effect on HAP 
emissions, including cyclones, multiclones, and baghouses. Wet control 
devices such as wet scrubbers and WESP are used primarily for PM 
control but may also affect (either positively or negatively) HAP 
emissions. The proposed rule did not specify where inlet sampling sites 
should be located when the HAP control device is preceded by a wet 
scrubber or WESP. As a result of industry comments on the proposed 
rule, Sec.  63.2262(d)(1) of the final PCWP rule requires that, ``* * * 
for HAP-altering controls in sequence, such as a wet control device 
followed by a thermal oxidizer, sampling sites must be located at the 
functional inlet of the control sequence (e.g., prior to the wet 
control device) and at the outlet of the control sequence (e.g., 
thermal oxidizer outlet) and prior to any releases to the atmosphere.''
    Following signature of the final rule, a stakeholder experienced 
with testing PCWP process units indicated that some coupled control 
systems are configured such that obtaining representative emissions 
measurements at sampling locations prior to the wet control device is 
not possible (e.g., inlet sampling locations fail to meet the criteria 
in Method 1 of 40 CFR part 60, appendix A). However, representative 
sampling could be accomplished at the outlet to the wet control device 
and inlet to the organic HAP control device. For those situations where 
coupled control systems are used to meet a compliance option that 
requires inlet sampling, we agree that sampling at the inlet of the HAP 
control device is sufficient and are proposing to amend the language in 
Sec.  63.2262(d)(1) to allow this alternative.
2. Definitions
    Tube dryer. Unlike in the proposed PCWP rule, primary tube dryers 
and secondary tube dryers are treated as separate process units in the 
final rule as a result of public comments received on the proposed rule 
(see 69 FR 45961-45962, July 30, 2004). Definitions of primary tube 
dryer and secondary tube dryer were added to the final rule to 
distinguish between the two types of tube dryers. The final rule also 
contains an associated definition of ``tube dryer,'' which is the same 
definition that was proposed. Following signature of the final rule, 
some industry representatives expressed concern that the definitions of 
tube dryer and secondary tube dryer could be misinterpreted to include 
ductwork used to pneumatically transfer hot wood furnish from a primary 
tube dryer to a holding bin, even though no heat is applied to the 
furnish as would occur for a secondary tube dryer. The promulgated 
definition indicates that the tube dryer is ``* * * operated at 
elevated temperature and used to reduce the moisture of wood * * *'' 
(which could occur with hot material passing though a duct even if no 
heat is applied). Given that tube dryers look like ductwork, we agree 
that this could be confusing to permitting authorities. To prevent 
misinterpretations and clarify that heat is applied in the tube dryer, 
we are proposing to amend the definition of ``tube dryer'' to replace 
the words ``operated at elevated temperature and used'' with ``operated 
by applying heat.''
    Affected source. Following Administrator signature of the final 
PCWP rule, it was brought to our attention that applicability of the 
final PCWP rule and the Industrial/Commercial/Institutional Boilers and 
Process Heaters NESHAP (40 CFR part 63, subpart DDDDD; referred to as 
the ``Boilers/Process Heaters rule'' throughout the remainder of this 
preamble) was unclear with respect to combustion units that direct-fire 
dryers. When a combustion unit supplies heat by directly exhausting 
combustion gas through a dryer, we would consider the dryer to be a 
``direct-fired dryer.'' The HAP emissions from a direct-fired dryer are 
actually a combination of the emissions from the combustion unit 
exhausting into the dryer and the emissions that result from drying the 
wood. Because the final PCWP rule regulates emissions from direct-fired 
dryers, those combustion unit exhaust streams that direct-fire dryers 
would not be subject to the requirements of the final Boilers/Process 
Heaters rule. Section 63.7491(l) of the final Boilers/Process Heaters 
rule states that any boiler or process heater specifically listed as an 
affected source in another standard under 40 CFR part 63 is not subject 
to the Boilers/Process Heaters rule. Confusion has resulted because the 
PCWP affected source definition contains no mention of combustion units 
(e.g., boilers or process heaters). To clarify applicability of the 
final PCWP rule, we are proposing to amend the definition of ``affected 
source'' to clearly state that combustion unit exhaust streams used to 
direct-fire dryers are part of the PCWP affected source.
    Our proposed amendment to the definition of ``affected source'' 
specifically refers to ``any combustion unit exhaust stream'' rather 
than to individual combustion units. There are numerous configurations 
of combustion units and drying operations in the PCWP industry 
including, for example, suspension burners that are built into 
individual dryers and stand-alone combustion units. Stand-alone 
combustion units can have several exhaust streams including, for 
example, exhaust streams that directly fire multiple dryers and exhaust 
streams that provide heat for other uses (e.g., indirect heat for a 
thermal oil heater). The exhaust streams that directly fire dryers 
would be part of the PCWP

[[Page 44016]]

affected source because the combustion gases come into direct contact 
with the wood material, and the dryer exhaust is a mixture of 
combustion gases and process gases. An exhaust stream that supplies 
indirect heat for other uses would be part of the PCWP affected source 
if it is eventually routed through the direct-fired dryers, such that 
it too contacts the wood material and becomes a mixture of combustion 
gases and process gases. However, if the indirect heat exhaust stream 
does not routinely pass through the direct-fired dryers, then this 
exhaust stream would be subject to the final Boilers/Process Heaters 
rule. Thus, as stated in the preamble to the final PCWP rule (see 69 FR 
45961 and 45963, July 30, 2004), there are combustion units in the PCWP 
industry that can be subject to both the PCWP and Boilers/Process 
Heaters final rules. We refer to ``combustion unit exhaust stream'' in 
our proposed amendment to clarify that different exhaust streams must 
be evaluated separately to determine applicability of the PCWP and 
Boilers/Process Heaters final rules for those individual exhaust 
streams.
    Direct-fired process unit. In tandem with our proposed addition to 
the definition of ``affected source,'' we are also proposing to move 
the definition of ``direct-fired process unit'' from appendix B to 
subpart DDDD to Sec.  63.2292 of subpart DDDD. Previously, the 
definition of ``direct-fired process unit'' was only needed in appendix 
B to subpart DDDD; however, since the proposed amendment to the 
``affected source'' definition refers to direct firing, the definition 
of ``direct-fired process unit'' would be needed for subpart DDDD as 
well. Appendix B to subpart DDDD references all of the definitions in 
Sec.  63.2292 of subpart DDDD.
    Plywood and composite wood products manufacturing facility. 
Following promulgation of the PCWP rule, we have received questions 
regarding applicability of the final PCWP rule to facilities that 
manufacture molded particleboard products. The promulgated definition 
of ``plywood and composite wood products manufacturing facility'' has 
caused some confusion because it does not specifically mention molded 
particleboard manufacturing. Molded particleboard is produced by hot 
pressing a mixture of wood particles and resin into a shape (e.g., a 
pallet, furniture part, toilet seat, etc.) using a press mold uniquely 
designed for the product. The press molds used for molded particleboard 
products are designed very differently from the platen or continuous 
presses used to manufacture conventional particleboard panels. Prior to 
promulgation, we determined that MACT for particleboard press molds is 
no emission reduction, and, therefore, there are no requirements in the 
final PCWP rule for these press molds. However, molded particleboard 
facilities can operate dry rotary dryers or green rotary dryers 
identical to those operated by conventional particleboard plants. 
Rotary dryers at molded particleboard manufacturing facilities were 
included in the MACT determination for PCWP dry and green rotary 
dryers. The final PCWP rule contains work practice requirements for dry 
rotary dryers and control requirements for green rotary dryers. In 
order to ensure that MACT is applied as intended for these dryers, we 
are proposing to amend the definition of ``plywood and composite wood 
products manufacturing facility'' to include molded particleboard 
manufacturing. Note that only those molded particleboard manufacturers 
that are major sources of HAP emissions are potentially affected by 
this clarification to the definition of ``plywood and composite wood 
products manufacturing facility.''
    Several other applicability questions have been raised regarding 
the definition of ``plywood and composite wood products manufacturing 
facility.'' As promulgated, a ``plywood and composite wood products 
manufacturing facility'' is ``a facility that manufactures plywood and/
or composite wood products by bonding wood material (fibers, particles, 
strands, veneers, etc.) or agricultural fiber, generally with resin 
under heat and pressure, to form a structural panel or engineered wood 
product * * *.'' We have received several questions about the 
applicability of the rule to products that are neither structural 
panels nor engineered wood products. Although some products that may 
not be considered structural panels or engineered wood products are 
listed at the end of the definition of ``plywood and composite wood 
products manufacturing facility'' (e.g., kiln-dried lumber), other 
products that we intended to cover are not listed in this definition. 
The phrase ``structural panel or engineered wood product'' was never 
intended to be a basis of exclusion from the source category; instead, 
it was intended to summarize the majority of products made at PCWP 
manufacturing facilities. Certain products that typically would not be 
considered either structural panels or engineered wood products were 
included in the MACT floor analysis and are subject to the promulgated 
rule. We propose to clarify our intent by amending the first sentence 
of the definition of ``plywood and composite wood products 
manufacturing facility'' to cover a wider variety of products.
    Plywood. We also received questions regarding applicability of the 
PCWP final rule to operations where veneer is glued (with heat and 
pressure) to form a curved wood component or onto a curved wood 
component rather than a flat panel. The promulgated definition of 
``plywood'' is `` * * * a panel product consisting of layers of wood 
veneers hot pressed together with resin. Plywood includes panel 
products made by hot pressing (with resin) veneers to a substrate such 
as particleboard, medium density fiberboard, or lumber.'' We did not 
define ``panel product'' in the final rule; however, we intended for 
the term to be interpreted broadly. We consider a product manufactured 
by hot-pressing veneers together or onto a substrate with resin to be 
plywood, regardless of the curvature of the end product. We propose to 
amend the definition of ``plywood'' to clarify our intent. There are no 
control requirements or work practice requirements for plywood pressing 
operations in the final PCWP rule. Therefore, facilities manufacturing 
products that meet the definition of ``plywood'' in the final rule (but 
have no other operations subject to the control, work practice, or 
operating requirements in the final PCWP rule) need only to submit an 
initial notification stating that they have no equipment subject to the 
rule (as discussed in the next section of this preamble).
    Molded particleboard. To supplement our proposed addition of molded 
particleboard manufacturing to the definition of ``plywood and 
composite wood products manufacturing facility,'' we are also proposing 
to add a definition of ``molded particleboard'' to subpart DDDD of 40 
CFR part 63.
    Engineered wood products. Following promulgation of the PCWP rule, 
we received several applicability questions regarding engineered wood 
products. To assist stakeholders in determining what products we 
consider to be engineered wood products, we are proposing to add a 
definition of ``engineered wood product'' to subpart DDDD of 40 CFR 
part 63.
3. Affected Sources With No Process Units Subject to the Compliance 
Options or Work Practice Requirements
    Following promulgation, we received several questions regarding 
applicability of general recordkeeping and reporting

[[Page 44017]]

requirements for affected sources with no equipment subject to specific 
requirements in the final rule. To clarify our intent in the final 
rule, we are proposing to add to subpart DDDD of 40 CFR part 63 a new 
section 63.2252, entitled ``What are the requirements for process units 
that have no control or work practice requirements?'' The proposed 
section states that you are not required to comply with the compliance 
options, work practice requirements, performance testing, monitoring, 
SSM plans, and recordkeeping or reporting requirements of this subpart, 
or any other requirements in subpart A of this part, except for the 
initial notification requirements in Sec.  63.9(b), for process units 
not subject to the compliance options or work practice requirements 
specified in Sec.  63.2240. Thus, affected sources without process 
units subject to the compliance options or work practice requirements 
(for example, lumber kilns, glue-laminated beams, or wood I-joists) 
would not be subject to the performance testing requirements, 
monitoring requirements, SSM plan requirements, and recordkeeping or 
reporting requirements of subpart DDDD, or any other requirements in 
subpart A of 40 CFR part 63. The proposed amendment is appropriate 
because no reports other than the initial notification would apply to 
these process units. The SSM plan is not necessary or required for 
process units not subject to specific requirements of the final rule 
because Sec.  63.6(e)(3) of subpart A of this part requires an affected 
source to develop an SSM plan for process units subject to and control 
equipment used to comply with the relevant standard. The final PCWP 
rule was not intended to require anything other than the initial 
notification for process units not subject to the compliance options or 
work practice requirements.
4. Incorporation by Reference of NCASI Test Methods
    With today's action, we are proposing to amend 40 CFR 63.14 by 
revising paragraph (f) to incorporate by reference one test method 
developed by the NCASI, pending review by EPA: Method ISS/FP-A105.01, 
Impinger Source Sampling Method for Selected Aldehydes, Ketones, and 
Polar Compounds. The method is available from the NCASI, Methods 
Manual, P.O. Box 133318, Research Triangle Park, NC 27709-3318 or at 
https://www.ncasi.org. It is also available from the docket for the 
proposed amendments (Docket ID No. OAR-2003-0048).
    The NCASI Method ISS/FP-A105.01 was developed as an additional test 
method for measuring total HAP that may be used for high-moisture 
sources. The NCASI Method ISS/FP-A105.01 is not appropriate for 
measurement of benzene. In today's proposed amendments, NCASI Method 
ISS/FP-A105.01, which is a self-validating method, would be allowed, 
pending our review, as an alternative to:
     EPA Method 320, Measurement of Vapor Phase Organic and 
Inorganic Emission by Extractive FTIR, for measuring methanol, 
formaldehyde, acetaldehyde, acrolein, phenol or total HAP;
     EPA Method 0011, Sampling for Selected Aldehyde and Ketone 
Emissions from Stationary Sources, for measuring formaldehyde;
     EPA Method 316, Sampling and Analysis for Formaldehyde 
Emissions from Stationary Sources in the Mineral Wool and Wool 
Fiberglass Industries, for measuring formaldehyde;
     EPA Method 308, Procedure for Determination of Methanol 
Emission from Stationary Sources, for measuring methanol;
     NCASI Method CI/WP-98.01, Chilled Impinger Method for Use 
at Wood Products Mills to Measure Formaldehyde, Methanol, and Phenol, 
for measuring formaldehyde or methanol; and
     NCASI Method IM/CAN/WP-99.02, Impinger/Canister Source 
Sampling Method for Selected HAPs at Wood Products Facilities, for 
measuring methanol, formaldehyde, acetaldehyde, acrolein, phenol or 
total HAP.

B. Amendments to Appendix B to Subpart DDDD of 40 CFR Part 63

1. Addition of Emissions Estimation Procedures
    Appendix B to subpart DDDD provides the methodology and criteria 
for demonstrating that your affected source is part of the low-risk 
subcategory of PCWP manufacturing facilities. As promulgated, appendix 
B to subpart DDDD requires emissions testing of all PCWP process units 
for up to 13 HAP. Table 2 of this preamble summarizes the process units 
that must be tested for each HAP and the emissions test methods 
specified in appendix B to subpart DDDD, as promulgated, for each HAP.

   Table 2.--Emissions Test Methods Specified in Appendix B to Subpart
                          DDDD, as Promulgated
------------------------------------------------------------------------
                                                       Specified test
             HAP                  Process units           method(s)
------------------------------------------------------------------------
Acetaldehyde, acrolein,       All process units...  NCASI IM/CAN/WP-
 formaldehyde, phenol.                               99.02 or EPA Method
                                                     320 or ASTM D6348-
                                                     03.
Benzene.....................  All process units...  EPA Method 320 or
                                                     ASTM D6348-03.
Methylene diphenyl            Presses that process  EPA Method 320 or
 diisocyanate (MDI).           board containing      Conditional Test
                               MDI resin.            Method 031.
Arsenic, beryllium, cadmium,  Direct-fired process  EPA Method 29.
 chromium, lead, nickel,       units.
 manganese.
------------------------------------------------------------------------
Notes: EPA Method 320 is located in 40 CFR part 63, appendix A. EPA
  Method 29 is located in 40 CFR part 60, appendix A. The NCASI IM/CAN/
  WP-99.02 and ASTM D6348-03 were incorporated by reference (see 40 CFR
  63.14) and Conditional Test Method 031 is posted at https://www.epa.gov/
ttn/emc/ctm.html.

    Following promulgation, stakeholders commented that emissions 
testing is not feasible or necessary for every process unit. The 
stakeholders claimed that many PCWP process units are not configured 
for emissions testing and that testing of every type of PCWP process 
unit (especially those with insignificant emissions) is not necessary 
to ensure an accurate assessment of risk. In addition, the stakeholders 
stated that requiring emissions testing for acrolein and benzene from 
all PCWP process units is not justified by the available data, which 
show that emissions of acrolein and benzene are frequently not detected 
in the exhausts from many types of PCWP process units. The stakeholders 
also requested that HAP metals emissions testing be limited to those 
direct-fired process units that fire fuels other than natural gas and 
that fuel analysis be allowed as an alternative to HAP metals emissions 
testing.
    Selection of Process Units to be Included in Low-risk 
Demonstration. EPA has determined that every process

[[Page 44018]]

unit with potentially significant emissions, including very small 
emission sources, must be included in the low-risk demonstration 
because the low-risk demonstration is based on the cumulative risk from 
the process units within the PWCP affected source. Generally, this 
means that EPA has included all process units with any detectable 
emissions. However, we wanted to determine if costs could be lowered 
without affecting the quality of the emission estimates. So, we 
explored the feasibility of testing each type of PCWP process unit and 
available emissions estimation methods. We must ensure an accurate 
emissions determination for the affected source, given that the purpose 
of the low-risk demonstration is to certify that a PCWP affected source 
poses a risk to human health and the environment less than the low-risk 
criteria specified in appendix B to subpart DDDD \2\ and is eligible to 
become exempt from MACT compliance requirements. Therefore, for 
purposes of the low-risk demonstration, we prefer to have emissions 
test data over emissions estimates when emissions test data can be 
reasonably obtained.
---------------------------------------------------------------------------

    \2\ To be considered low risk, the PCWP affected source must 
meet the following criteria: (1) The maximum off-site individual 
lifetime cancer risk at a location where people live is less than 
one in one million for carcinogenic chronic inhalation effects; (2) 
every maximum off-site target-organ specific hazard index (TOSHI) 
(or, alternatively, an appropriately site-specific set of hazard 
indices based on similar or complementary mechanisms of action that 
are reasonably likely to be additive at low dose or dose-response 
data for your affected source's HAP mixture) at a location where 
people live is less than or equal to 1.0 for noncarcinogenic chronic 
inhalation effects; and (3) the maximum off-site acute hazard 
quotients for acrolein and formaldehyde are less than or equal to 
1.0 for noncarcinogenic acute inhalation effects.
---------------------------------------------------------------------------

    We believe that it is feasible to perform emissions testing for the 
following types of PCWP process units: Fiberboard mat dryers (heated 
and cooling zones), green rotary dryers, hardboard ovens, press 
predryers, pressurized refiners, primary tube dryers, secondary tube 
dryers, reconstituted wood product board coolers, reconstituted wood 
product presses, softwood veneer dryers (heated zones), rotary strand 
dryers, conveyor strand dryers (all zones), dry rotary dryers, veneer 
redryers (heated by conventional means), hardwood veneer dryers (heated 
zones), rotary agricultural fiber dryers, agricultural fiber board 
presses, paddle-type particle dryers, agricultural fiberboard mat 
dryers, and atmospheric refiners. Therefore, emissions testing would 
continue to be required for all of the above listed process units. Most 
of the process units listed above have control or work practice 
requirements under subpart DDDD.
    We believe that emissions testing is not feasible for the following 
types of process units: Fiberboard mat dryers (fugitive emissions), 
softwood veneer dryer (cooling zones and fugitive emissions), hardwood 
veneer dryers (cooling zones), radio-frequency veneer redryers, 
softwood plywood presses, hardwood plywood presses, engineered wood 
products presses, humidifiers, formers, blenders, sanders, saws, fiber 
washers, chippers, log vats, lumber kilns, storage tanks, wastewater 
operations, stand-alone digesters, veneer kilns, particleboard press 
molds, and particleboard extruders. Some of these process units are 
vented primarily for dust control and reclaim of process materials, and 
their venting systems are not designed for flow measurement or 
measurement of organic gases. Some of the process units are not vented 
(i.e., are fugitive emissions sources) or are only partially vented. 
The configuration of these process units, in terms of how and if they 
vent to the atmosphere, varies significantly from plant to plant. 
Often, the emission points from these process units (where defined 
emission points exist) are not configured such that EPA Method 1 or EPA 
Method 2 (40 CFR part 60, appendix A) criteria for selection of 
sampling ports and measurement of gas velocity could be met. Emissions 
data are available from an extensive emissions testing program where 
testable units in several of the process unit groups were identified. 
These emissions data (along with other available data collected during 
NESHAP development) have been used to develop emission factors. Almost 
all of the test data were reviewed by industry experts. All the data, 
except the lumber kiln data, were reviewed by EPA, were available for 
the public to review at proposal, and were available for public review 
during EPA's AP-42 review process. (See legacy docket A-98-44, items 
titled ``Emission Factor Documentation for AP-42 Section 10.5, Plywood 
Manufacturing,'' ``Emission Factor Documentation for AP-42 Section 
10.6.3,'' ``Medium Density Fiberboard Manufacturing,'' ``Emission 
Factor Documentation for AP-42 Section 10.6.2,'' ``Particleboard 
Manufacturing,'' ``Emission Factor Documentation for AP-42 Section 
10.6.1,'' ``Waferboard/Oriented Strandboard Manufacturing,'' and 
``Documentation of Emission Factor Development for the Plywood and 
Composite Wood Products Manufacturing NESHAP.'') In addition, the 
lumber kiln data are now available in ``Procedures for Determining 
Emissions from Plywood and Composite Wood Products Process Units for 
Low-Risk Demonstrations.'' Therefore, as discussed later in this 
section, we are proposing to allow that emission factors be used to 
estimate emissions from the hard-to-test process units for purposes of 
the PCWP low-risk demonstrations. Other emissions estimation methods 
(e.g., engineering estimates) are proposed to be allowed for hard-to-
test process units for which no emission factors are available.
    Based on the available data, three types of process units 
(miscellaneous coating operations, softwood veneer dryer fugitive 
emissions, and log chipping operations) are hard to test but do not 
emit any of the HAP listed in appendix B to subpart DDDD. Thus, 
miscellaneous coating operations, softwood veneer dryer fugitive 
emissions, and log chipping operations would not need to be considered 
in the low-risk demonstration, under the proposed amendments.
    There may be additional ancillary PCWP process units for which no 
HAP data are available (e.g., log storage piles and material handling 
operations). Such processes are likely to be hard to test. No 
information is available to conclude that there are appendix B to 40 
CFR part 63 HAP emissions from other PCWP processes not mentioned 
elsewhere in today's proposed amendments. Nevertheless, in the event 
that there may be an additional HAP emissions source within the PCWP 
affected source that is not listed elsewhere in appendix B to subpart 
DDDD, a category of ``other ancillary processes that emit appendix B 
HAP emissions'' is proposed to be added to appendix B to subpart DDDD, 
and engineering estimates for all of the appendix B HAP would be 
allowed for such processes. We request comment (and emissions data, if 
available) regarding any PCWP emissions sources not listed in appendix 
B to subpart DDDD that are known to emit appendix B HAP emissions. It 
is not our intent to require quantification of emissions for ancillary 
processes that do not emit appendix B HAP. Our intent with the category 
of ``other ancillary processes that emit appendix B HAP emissions'' is 
to capture unique equipment (e.g., a one-of-a-kind dryer) that could 
reasonably be expected to emit appendix B HAP, but is not otherwise 
covered in the process unit definitions provided in subpart DDDD of 40 
CFR part 63 and appendix B to subpart DDDD. Therefore, we request 
comment on whether it would be appropriate to include a list of 
``insignificant

[[Page 44019]]

activities'' for purposes of appendix B to subpart DDDD. We also 
request comment on what activities should be included in such a list. 
Commenters may want to refer to a list of proposed insignificant 
activities in the docket which was submitted by AF&PA, titled 
``Proposed Categorical Insignificant Sources.''
    To incorporate emissions estimation procedures, our proposed 
amendment to appendix B to subpart DDDD would add a table (table 2A to 
appendix B to subpart DDDD) that states for each process unit whether 
emissions testing is required or emissions estimation is allowed for 
each of the appendix B HAP. If emissions estimates are allowed, then 
the proposed table 2A to appendix B to subpart DDDD would specify the 
emission factor (or other emissions estimation technique) to be used in 
developing the emissions estimates. Related text is proposed to be 
added to sections 5(a) and 5(k) of appendix B to subpart DDDD. Section 
6(a) of appendix B to subpart DDDD is also being amended to clarify 
that it applies when emissions estimation or testing is performed. We 
are proposing to add definitions of process units not already defined 
in subpart DDDD to section 15 of appendix B to subpart DDDD. In 
addition, we are proposing to add text to section 8(a)(3) of appendix B 
to subpart DDDD to specify that emissions estimate calculations must be 
submitted with the low-risk demonstration.
    Selection of Emissions Estimation Procedures. As mentioned 
previously, emission factors could be used under the proposed 
amendments to estimate emissions from most of the hard-to-test process 
units. To streamline completion and review of the low-risk 
demonstrations, our proposed amendment to appendix B to subpart DDDD 
specifies emission factors that are to be used in low-risk 
demonstrations. We are not proposing to allow facilities to choose 
their own emission factors (from AP-42 or elsewhere) because we believe 
we have the most extensive collection of PCWP HAP emissions data 
available and because additional time would be required for EPA to 
verify the emission factors selected for each process unit. The 
emission factors proposed to be included in appendix B to subpart DDDD 
are the maximum emission factors available for each type of process 
unit (i.e., the emission factor resulting from the highest emissions 
test). Use of the maximum emission factor builds conservatism into the 
emissions estimates to help account for unit-to-unit variability and 
ensures protection of human health. In addition, the maximum emission 
factor is available for all process units for which we have sufficient 
data. While we believe the maximum emission factor is the best 
statistical approach as explained above, we request comment on using 
other statistical approaches. Facilities approaching the limits of the 
low-risk criteria may refine their analysis of HAP emitted by 
reconfiguring their process unit, if possible, and conducting emissions 
testing.
    Estimation of emissions would be allowed for acetaldehyde, 
acrolein, formaldehyde, phenol, and benzene. In addition, estimation of 
methylene diphenyl diisocyanate (MDI) emissions would be allowed for 
process units processing material containing MDI resin. Except for 
lumber kilns, estimation of HAP metals emissions is not necessary 
because the hard-to-test process units are heated by means other than 
direct firing (if heated at all). In some cases, a particular HAP 
listed on appendix B to subpart DDD was not detected in any emissions 
test run conducted for a process unit type. We are proposing that no 
emissions estimate be developed for HAP that have not been detected 
from a process unit group because the available emission factors are 
based on values equal to one-half of the method detection limit (MDL) 
and are of limited use. Engineering estimates are proposed in some 
cases where all of the data are non-detect but the available data sets 
are small, and it is reasonable to believe that a particular HAP could 
be emitted. In some cases, no applicable emission factor is available 
for certain HAP and process unit combinations where we expect the HAP 
could be detected (e.g., phenol from oriented strandboard (OSB) 
blenders and MDI from MDI blenders). We are proposing to accept 
engineering estimates based on information available to the facility in 
cases where no applicable emission factor is available for a HAP that 
may reasonably be expected to be emitted from a certain type of process 
unit.
    Our data base of emission factors does not include emission factors 
for lumber kilns. It is difficult to measure emissions from lumber 
kilns due to kiln air flow design, fugitive emissions, and the lengthy 
kiln batch cycle (e.g., 24 hours for softwood kilns, days for hardwood 
kilns). Therefore, little emissions test data are available for use in 
developing HAP emission factors for lumber kilns. Methods for 
quantifying lumber kiln flow rates vary from test to test. Most of the 
emissions test data that are available (generally total hydrocarbon 
(THC) data) contain calculated flow rates or other assumptions that 
bring the validity of the data into question. A few tests have been 
conducted on both small- and full-scale lumber kilns to determine 
emissions of HAP (generally formaldehyde and methanol). We reviewed 
available information on lumber kiln emissions and selected the maximum 
emission factors of HAP listed in appendix B to subpart DDDD from the 
literature. Today, we are proposing these emission factors for purposes 
of estimating lumber kiln emissions for the low-risk demonstration. 
Engineering estimates of HAP metals emissions are proposed for direct-
fired lumber kilns. While emissions testing of full-scale lumber kilns 
has proven to be very difficult, studies have shown that testing of 
small-scale lumber kilns can be used to reasonably approximate 
emissions from full-scale lumber kilns if representative lumber samples 
are dried and the venting characteristics of the small-scale kiln mimic 
those of the full-scale kiln. Several U.S. universities and private 
laboratories operate small-scale kilns. To approximate emissions from 
full-scale kilns, a representative sample of lumber is taken from the 
full-scale kiln facility, packaged to prevent moisture loss, and 
shipped to the location of the small-scale kiln where the full-scale 
kiln's drying cycle (e.g., time and temperatures) is mirrored during 
emissions testing. Small-scale kilns are designed for more accurate air 
flow measurement and are less costly to test. In addition to proposing 
emission factor estimates based on the available information, we 
request comment on whether it would be appropriate to allow facilities 
to commission emissions testing at a representative small-scale lumber 
kiln for purposes of the low-risk demonstration. We also request 
comment on any standard procedures for submitting lumber samples and 
conducting small-scale kiln emissions testing that should be 
incorporated into or referenced by appendix B to subpart DDDD. When 
submitting comments on standard procedures, please refer to a document 
in the docket entitled ``Considerations for a Small-scale Kiln Emission 
Testing Program.''
    Emission factors are not available for PCWP resin storage tanks and 
PCWP wastewater/process water operations. For resin storage tanks, we 
are proposing to specify in appendix B to subpart DDDD that facilities 
may apply the maximum emissions estimates reported in our MACT survey 
responses for each tank (depending on the tank contents). We are 
proposing to specify that facilities generate engineering estimates of 
appendix B HAP emissions

[[Page 44020]]

from wastewater/process water operations. Alternatively, we have 
developed computer models for estimating emissions from storage tanks 
(TANKS) and wastewater/process water operations (WATER9). Both models 
are available at https://www.epa.gov/ttn/chief/software/. The 
proposed amendments to appendix B to subpart DDDD allow facilities to 
use these models to develop more refined estimates of emissions from 
resin storage tanks and wastewater/process water operations. We also 
request comment on other methods that could be used in appendix B to 
subpart DDDD to quantify emissions from wastewater/process water 
operations, such as the approach outlined in forms VII and VIII of 
appendix C to 40 CFR part 63 and described further with respect to the 
PCWP industry in the supporting information for today's proposed 
amendments.
    Application of Emissions Estimation Procedures. To apply emission 
factors, facilities would need the emission factor (in terms of pounds 
of HAP per process unit throughput) supplied in appendix B to subpart 
DDDD and their site-specific process unit throughput. None of the hard-
to-test process units are equipped with HAP control devices; therefore, 
control efficiency is not a variable in the emission factor estimates 
for low-risk demonstrations. Facilities may also use process unit 
throughput or other parameters in their engineering estimates allowed 
where emission factors were not available.
    Process unit throughput could be based on process unit capacity or 
actual throughput. Section 11 of appendix B to subpart DDDD requires 
facilities to incorporate parameters that define the affected source as 
part of the low-risk subcategory (including production rate) as 
federally enforceable limits in their title V permits. Furthermore, 
according to section 13(a) of appendix B to subpart DDDD, facilities 
must certify with their ongoing title V certifications that the basis 
for their low-risk demonstrations have not changed (including any 
process changes that would increase HAP emissions, such as a production 
rate increase). Given these requirements, we are proposing to allow 
facilities to use the process unit throughput that they wish to 
incorporate into their title V permit in their emissions estimates for 
the low-risk demonstration. We decided not to mandate use of process 
unit capacity for the emissions estimations in order to give facilities 
the flexibility to choose a federally enforceable permit limit on their 
production rate should they wish to minimize emissions by limiting 
production.
    Some PCWP process units have multiple emissions points of varying 
height. For purposes of the low-risk demonstration, it is necessary to 
have an emission rate and emissions release parameters (e.g., stack 
height) associated with each emission point. Thus, we are proposing 
that emissions estimates developed for process units with multiple 
emission points be divided evenly across the emission points. For 
example, emissions estimated for a softwood plywood press with four 
vents would be divided by four, with one-fourth of the estimated 
emissions being assigned to each press v