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Proposed Rule

Air Quality: Revision to the Regulatory Definition of Volatile Organic Compounds-Requirements for t-Butyl Acetate

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Start Preamble

AGENCY:

Environmental Protection Agency.

ACTION:

Proposed rule.

SUMMARY:

The Environmental Protection Agency (EPA) is proposing to amend the EPA's regulatory definition of volatile organic compounds (VOCs) under the Clean Air Act (CAA). The regulatory definition of VOCs currently excludes t-butyl acetate (also known as tertiary butyl acetate or TBAC; CAS NO: 540-88-5) for purposes of VOC emissions limitations or VOC content requirements on the basis that it makes a negligible contribution to tropospheric ozone formation. However, the current definition includes TBAC as a VOC for purposes of all recordkeeping, emissions reporting, photochemical dispersion modeling and inventory requirements which apply to VOCs. The regulatory definition requires that TBAC be uniquely identified in emission reports. TBAC is used as a solvent in paints, inks and adhesives, in which it substitutes for compounds that are regulated as VOCs. This proposed action would remove recordkeeping, emissions reporting, photochemical dispersion modeling and inventory requirements related to the use of TBAC as a VOC.

The EPA has concluded that these requirements are not resulting in useful information. Furthermore, there is no evidence that TBAC is being used at levels that would cause concern for ozone formation. As these requirements are unnecessary and can be burdensome for states and industry, we are proposing to revoke these requirements and exclude TBAC from the regulatory definition of VOCs for all purposes. Note that the EPA is not reconsidering its determination that TBAC is “negligibly reactive” with respect to ground-level ozone formation.

DATES:

Comments must be received on or before April 6, 2015.

Public Hearing. If anyone contacts the EPA requesting a public hearing concerning the proposed regulation on or before March 9, 2015 we will hold a public hearing on March 23, 2015. If a public hearing is requested, it will be held at 10 a.m. on the EPA campus in Research Triangle Park, NC, or at an alternate site nearby. Please refer to SUPPLEMENTARY INFORMATION for additional information on the comment period and the public hearing.

ADDRESSES:

Submit your comments, identified by Docket ID No. EPA-HQ-OAR-2013-0795, by one of the following methods:

  • Federal eRulemaking Portal: http://www.regulations.gov. Follow the on-line instructions for submitting comments
  • Email: a-and-r-Docket@epamail.epa.gov. Include docket ID No. EPA-HQ-OAR-2013-0795 in the subject line of the message.
  • Fax: (202) 566-9744.
  • Mail: Environmental Protection Agency, EPA Docket Center (EPA/DC), Mail Code: 28221T, Attention Docket ID No. EPA-HQ-OAR-2013-0795, 1200 Pennsylvania Ave. NW., Washington, DC 20460.
  • Hand/Courier Delivery: EPA Docket Center, Room 3334, EPA WJC West Building, 1301 Constitution Avenue NW., Washington, DC 20004, Attention Docket ID No. EPA-HQ-OAR-2013-0795. 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. EPA-HQ-OAR-2013-0795. The EPA's policy is that all comments received will be included in the public docket without change and may be made available online at www.regulations.gov, including any personal information provided, unless the comment includes information claimed to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Do not submit information that you consider to be CBI or otherwise protected through www.regulations.gov, or email. The 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 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/​epahome/​dockets.htm.

Docket: All documents in the docket are listed in the www.regulations.gov index. Although listed in the index, some information is not publicly available, i.e., 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 Start Printed Page 6482either electronically in www.regulations.gov or in hard copy at the Docket ID No. EPA-HQ-OAR-2013-0795, EPA, WJC West Building, Room 3334, 1301 Constitution Ave. NW., Washington, DC. The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is (202) 566-1744, and the telephone number for the Air and Radiation Docket is (202) 566-1742.

Start Further Info

FOR FURTHER INFORMATION CONTACT:

Ms. Souad Benromdhane, Office of Air Quality Planning and Standards, Health and Environmental Impacts Division, Mail Code C539-07, Environmental Protection Agency, Research Triangle Park, NC 27711; telephone: (919) 541-4359; fax number: (919) 541-5315; email address: benromdhane.souad@epa.gov.

End Further Info End Preamble Start Supplemental Information

SUPPLEMENTARY INFORMATION:

Table of Contents

I. General Information

A. Does this action apply to me?

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

C. How can I find information about a possible public hearing?

II. Background

A. The EPA's VOC Exemption Policy

B. History of the VOC Exemption for TBAC Including the Unique Recordkeeping, Emissions Reporting, Photochemical Dispersion Modeling and Inventory Requirements

C. Petition to Remove Recordkeeping and Reporting Requirements from the TBAC Exemption

III. The EPA's Assessment of the Petition

IV. Proposed Action

V. 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 (PRA)

C. Regulatory Flexibility Act (RFA)

D. Unfunded Mandates Reform Act (UMRA)

E. Executive Order 13132: Federalism

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

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

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

I. National Technology Transfer and Advancement Act (NTTAA)

J. Executive Order 12898: Federal Actions to Address Environmental Justice in Minority and Low-Income Populations

I. General Information

A. Does this action apply to me?

Entities potentially affected by this proposed rule include, but are not necessarily limited to, state and local air pollution control agencies that prepare VOC emission inventories and ozone attainment demonstrations for state implementation plans (SIPs). These agencies would be relieved of the requirements to separately inventory emissions of TBAC. This proposed action may also affect manufacturers, distributors and users of TBAC and TBAC-containing products, which may include paints, inks and adhesives. This action would allow state air agencies to no longer require these entities to report emissions of TBAC.

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

1. Submitting CBI: Do not submit this information to the EPA through www.regulations.gov or email. Clearly mark the part or all of the information that you claim to be CBI. For CBI information in a disk or CD-ROM that you mail to 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 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.

2. Tips for Preparing Your Comments. When submitting comments, remember to:

  • Identify the rulemaking by docket number and other identifying information (subject heading, Federal Register date and page number).
  • Follow directions—The Agency may ask you to respond to specific questions or organize comments by referencing a Code of Federal Regulations (CFR) part or section number.
  • Explain why you agree or disagree, suggest alternatives, and substitute language for your requested changes.
  • Describe any assumptions and provide any technical information and/or data that you used.
  • Provide specific examples to illustrate your concerns, and suggest alternatives.
  • Explain your views as clearly as possible, avoiding the use of profanity or personal threats.
  • Make sure to submit your comments by the comment period deadline identified.

C. How can I find information about a possible public hearing?

To request a public hearing or information pertaining to a public hearing, contact Ms. Eloise Shepherd, Health and Environmental Impacts Division, Office of Air Quality Planning and Standards (C504-02), U.S. Environmental Protection Agency, Research Triangle Park, NC 27711; telephone number (919) 541-5507; fax number (919) 541-0804; email address: shepherd.eloise@epa.gov.

II. Background

A. The EPA's VOC Exemption Policy

Tropospheric ozone, commonly known as smog, is formed when VOCs and nitrogen oxides (NOX) react in the atmosphere in the presence of sunlight. Because of the harmful health effects of ozone, the EPA and state governments limit the amount of VOCs that can be released into the atmosphere. VOCs are organic compounds of carbon, many of which form ozone through atmospheric photochemical reactions. Different VOCs have different levels of reactivity. That is, they do not react to form ozone at the same speed or do not form ozone to the same extent. Some VOCs react slowly or form less ozone; therefore, changes in their emissions have limited effects on local or regional ozone pollution episodes. It has been the EPA's policy that organic compounds with a negligible level of reactivity should be excluded from the regulatory definition of VOCs so as to focus control efforts on compounds that do significantly increase ozone concentrations. The EPA also believes that exempting such compounds creates an incentive for industry to use negligibly reactive compounds in place of more highly reactive compounds that are regulated as VOCs. The EPA lists compounds that it has determined to be negligibly reactive in its regulations as being excluded from the regulatory definition of VOCs (40 CFR 51.100(s)).

The CAA requires the regulation of VOCs for various purposes. Section 302(s) of the CAA specifies that the EPA has the authority to define the meaning of “VOCs,” and hence what compounds shall be treated as VOCs for regulatory purposes. The policy of excluding negligibly reactive compounds from the regulatory definition of VOCs was first laid out in the “Recommended Policy on Control of Volatile Organic Compounds” (42 FR 35314, July 8, 1977) and was supplemented Start Printed Page 6483subsequently with the “Interim Guidance on Control of Volatile Organic Compounds in Ozone State Implementation Plans” (70 FR 54046, September 13, 2005). The EPA uses the reactivity of ethane as the threshold for determining whether a compound has negligible reactivity. Compounds that are less reactive than, or equally reactive to, ethane under certain assumed conditions may be deemed negligibly reactive and, therefore, suitable for exemption by EPA from the regulatory definition of VOCs. Compounds that are more reactive than ethane continue to be considered VOCs for regulatory purposes and, therefore, are subject to control requirements. The selection of ethane as the threshold compound was based on a series of smog chamber experiments that underlay the 1977 policy.

The EPA uses two different metrics to compare the reactivity of a specific compound to that of ethane: (1) The reaction rate constant (known as kOH) with the hydroxyl radical (OH) and (2) the maximum incremental reactivity (MIR) on ozone production per unit mass basis. Differences between these metrics and the rationale for their selection is discussed further in the 2005 Interim Guidance (70 FR 54046, September 13, 2005).

B. History of the VOC Exemption for TBAC Including the Unique Recordkeeping, Emissions Reporting, Photochemical Dispersion Modeling and Inventory Requirements

On January 17, 1997, ARCO Chemical Company (now known as and from here forward referred to as LyondellBasell) submitted a petition to the EPA which requested that the EPA add TBAC to the list of compounds which are designated negligibly reactive in the regulatory definition of VOCs at 40 CFR 51.100(s). The materials submitted in support of this petition are contained in Docket EPA-HQ-OAR-2003-0084. LyondellBasell's case for TBAC being less reactive than ethane was based primarily on the use of relative incremental reactivity factors set forth in a 1997 report by Carter, et al.[1] Although the kOH values for TBAC are higher than for ethane, Carter's results indicated that the MIR value for TBAC, expressed in units of grams of ozone per gram of TBAC, was between 0.43 and 0.48 times the MIR for ethane, depending on the chemical mechanism used to calculate the MIR. In other words, TBAC formed less than half as much ozone as an equal weight of ethane under the conditions assumed in the calculation of the MIR scale.

On September 30, 1999, the EPA proposed to revise the regulatory definition of VOCs to exclude TBAC, relying on the comparison of MIR factors expressed on a mass basis to conclude that TBAC is negligibly reactive (64 FR 52731, September 30, 1999). However, in the final rule, the EPA concluded at that time that even “negligibly reactive” compounds may contribute significantly to ozone formation if present in sufficient quantities and that emissions of these compounds need to be represented accurately in photochemical modeling analyses. In addition to these general concerns about the potential cumulative impacts of negligibly reactive compounds, the need to maintain recordkeeping and reporting requirements for TBAC was further justified by the potential for widespread use of TBAC, the fact that its relative reactivity falls close to the borderline of what has been considered negligibly reactive, and continuing efforts to assess long-term health risks.[2] Based on these conclusions, the EPA promulgated a final rule under which TBAC was excluded from the definition of VOCs for purposes of VOC emissions limitations or VOC content requirements, but continued to be defined as a VOC for purposes of all recordkeeping, emissions reporting, and inventory requirements which apply to VOCs (69 FR 69298, November 29, 2004).

In the final rule, the EPA argued that the recordkeeping and reporting requirements were not new requirements for TBAC as industry and states were already subject to such requirements to report TBAC as a VOC prior to the exemption. However, in practice, the rule created a new, distinct recordkeeping and reporting burden by requiring that TBAC be “uniquely identified” in emission reports, rather than aggregated with other compounds as VOC. The final rule explained that the EPA was in the process of reviewing its overall VOC exemption policy and that the potential for retaining recordkeeping and reporting requirements for compounds exempted from the definition of VOCs in the future would be considered in that process. That process led to the development of the 2005 Interim Guidance (70 FR 54046, September 13, 2005), which encouraged the development of speciated inventories for highly reactive compounds and identified the voluntary submission of emissions estimates for exempt compounds as an option for further consideration, but did not recommend mandatory reporting requirements associated with future exemptions. Thus, TBAC is the only compound that is excluded from the VOCs definition for purposes of emission controls but is still considered a VOC for purposes of recordkeeping and reporting.

C. Petition to Remove Recordkeeping and Reporting Requirements from the TBAC Exemption

The EPA received a petition from LyondellBasell in December 2009, which was re-affirmed in November 2011, requesting the removal of recordkeeping and reporting requirements from the final rule to exempt TBAC from the regulatory VOCs definition. LyondellBasell contends that the emissions reporting requirements are redundant and present an unnecessary bureaucratic burden.

III. The EPA's Assessment of the Petition

In most cases, when a negligibly reactive VOC is exempted from the definition of VOCs, emissions of that compound are no longer recorded, collected, or reported to states or the EPA as part of VOC emissions. When the EPA exempted TBAC from the VOCs definition for purposes of control requirements, the EPA created a new category of compounds and a new reporting requirement. The new definition required that emissions of TBAC be reported separately by states and, in turn, by industry. However, the EPA did not issue any guidance on how TBAC emissions should be tracked and reported, and implementation of this requirement by states has thus been inconsistent. A few states have modified their rules and emissions inventory processes to track TBAC emissions separately and provide that information to the EPA. Others appear to have included TBAC with other undifferentiated VOCs in their emissions inventories. Thus, the data that have been collected to date as a result of these requirements are Start Printed Page 6484incomplete and inconsistent. In addition, the EPA has not established protocols for receiving and analyzing TBAC emissions data collected under the requirements of the rule.

Although the reactivity of TBAC and other negligibly reactive compounds is low, if emitted in large quantities, they could still contribute significantly to ozone formation in some locations. However, without speciated emissions estimates or extensive speciated hydrocarbon measurements, it is difficult to assess the impacts of any one exempted compound or even the cumulative impact of all of the exempted compounds.

In the 2004 TBAC rule, the EPA stated the primary objective of the recordkeeping and reporting requirements for TBAC was to address these cumulative impacts of “negligibly reactive” compounds and suggested that future exempt compounds may also be subject to such requirements. However, such requirements have not been included in any other proposed or final VOC exemptions since the TBAC decision. Having even high quality data on TBAC emissions alone is unlikely to be very useful in assessing the cumulative impacts of exempted compounds on ozone formation. Thus, the requirements are not achieving their primary objective to inform more accurate photochemical modeling in support of SIP submissions.

With regard to the concerns related to efforts to characterize long-term health risks associated with TBAC and its metabolite tertiary-butyl alcohol (TBA), since the rule was finalized, LyondellBasell performed additional toxicity testing and a health risk assessment and submitted the peer-consultation results to the EPA in 2009.[3] In addition, in 2006, the State of California published its own assessment of the potential health effects associated with TBA and TBAC.[4] The EPA is currently in the process of assessing the evidence for health risks from TBA through its Integrated Risk Information System (IRIS) program.[5] A draft of this assessment is expected to be circulated for public comment in 2015. The existing toxicity information being examined in the IRIS assessment does not rely on any of the data collected through the recordkeeping and reporting requirements, and thus those requirements do not appear relevant to any likely future determinations about the health risks associated with TBAC or TBA.

IV. Proposed Action

The EPA is proposing to revise certain aspects of the EPA's regulatory definition of VOCs under the CAA. The regulatory definition of VOCs currently excludes TBAC on the basis that it makes a negligible contribution to tropospheric ozone formation and contains a specific requirement for recordkeeping and reporting of TBAC emissions.

The recordkeeping, emissions reporting, photochemical dispersion modeling and inventory requirements for TBAC are not resulting in useful information. Furthermore, there is no evidence that TBAC is being used at levels that would cause concern for ozone formation. Additionally, the EPA believes these requirements, which are unique among all VOC-exempt compounds, are of limited utility because they do not provide sufficient information to judge the cumulative impacts of exempted compounds, and because they have not been consistently collected and reported. Because these requirements are not addressing any of the concerns as they were intended, the EPA proposes to revoke the requirements for TBAC and relieve industry and states of the associated information collection burden until such time that the EPA re-evaluates the necessity for reporting and recordkeeping of negligibly reactive compounds generally.

This proposed action would remove recordkeeping, emissions reporting, photochemical dispersion modeling and inventory requirements related to the use of TBAC. This action would not affect the existing exclusion of TBAC from the regulatory definition of VOCs for purposes of emission limits and control requirements.

We note that removal of the recordkeeping and reporting requirements does not indicate that the EPA has reached final conclusions about all aspects of the health effects posed by the use of TBAC or its metabolite TBA. The EPA is currently awaiting completion of the IRIS assessment on the potential risks involved with TBA and its toxicity. If it becomes clear that action is warranted due to the health risks of direct exposure to TBA or TBAC, the EPA will consider the range of authorities at its disposal to mitigate these risks appropriately.

V. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review and Executive Order 13563: Improving Regulation and Regulatory Review

This action is not a significant regulatory action and was therefore not submitted to the Office of Management and Budget (OMB) for review.

B. Paperwork Reduction Act (PRA)

This action does not impose an information collection burden under the provisions of the PRA. It does not contain any new recordkeeping or reporting requirements. This action would remove recordkeeping, emissions reporting, photochemical dispersion modeling and inventory requirements related to use of TBAC.

C. Regulatory Flexibility Act (RFA)

I certify that this action will not have a significant economic impact on a substantial number of small entities under the RFA. This action will not impose any requirements on small entities. This action would remove recordkeeping, emissions reporting, photochemical dispersion modeling and inventory requirements related to use of TBAC.

D. Unfunded Mandates Reform Act (UMRA)

This action does not contain any unfunded mandates as described in UMRA, 2 U.S.C. 1531-1538, and does not significantly or uniquely affect small governments. The action imposes no enforceable duty on any state, local or tribal governments or the private sector.

E. Executive Order 13132: Federalism

This action does not have federalism implications. It will not have substantial direct effects on the states, on the relationship between the national government and the states, or on the distribution of power and responsibilities among the various levels of government.

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

This action does not have tribal implications, as specified in Executive Order 13175. This proposed action would remove existing emission inventory reporting and other requirements that uniquely apply to Start Printed Page 6485TBAC among all VOC-exempt compounds. Thus, Executive Order 13175 does not apply to this rule.

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

This action is not subject to Executive Order 13045 because it is not economically significant as defined in E.O. 12866, and because the EPA does not believe the environmental health or safety risks addressed by this action present a disproportionate risk to children. This action would remove recordkeeping, emissions reporting, photochemical dispersion modeling and inventory requirements related to use of TBAC.

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

This action is not a “significant energy action” because it is not likely to have a significant adverse effect on the supply, distribution, or use of energy. This action would remove existing emission inventory reporting and other requirements that uniquely apply to TBAC among all VOC-exempt compounds.

I. National Technology Transfer and Advancement Act (NTTAA)

This action does not involve technical standards.

J. Executive Order 12898: Federal Actions to Address Environmental Justice in Minority and Low-Income Populations

The EPA believes the human health or environmental risks addressed by this action will not have disproportionately high and adverse human health or environmental effects on minority or low-income populations because it does not affect the level of protection provided to human health or the environment. The EPA did not conduct an environmental analysis for this rule because the EPA does not believe that removing the unique reporting requirements will lead to substantial and predictable changes in the use of TBAC in and near particular communities.

Start List of Subjects

List of Subjects in 40 CFR Part 51

  • Environmental protection
  • Administrative practice and procedure
  • Air pollution control
  • Ozone
  • Reporting and recordkeeping requirements
  • Volatile organic compounds
End List of Subjects Start Signature

Dated: January 29, 2015.

Gina McCarthy,

Administrator.

End Signature

For the reasons stated in the preamble, the Environmental Protection Agency proposes to amend part 51 of chapter I of title 40 of the Code of Federal Regulations as follows:

Start Part

PART 51—REQUIREMENTS FOR PREPARATION ADOPTION AND SUBMITTAL OF IMPLEMENTATION PLANS SUBPART F PROCEDURAL REQUIREMENTS

End Part Start Amendment Part

1. The authority citation for part 51, subpart F, continues to read as follows:

End Amendment Part Start Authority

Authority: 42 U.S.C. 7401, 7411, 7412, 7413, 7414, 7470-7479, 7501-7508, 7601, and 7602.

End Authority
[Amended]
Start Amendment Part

2. Section 51.100 is amended by:

End Amendment Part Start Amendment Part

a. Adding the term “t-butyl acetate;” before the phrase “perfluorocarbon compounds which fall into these classes:” to paragraph (s)(1) introductory text; and

End Amendment Part Start Amendment Part

b. Removing and reserving paragraph (s)(5).

End Amendment Part End Supplemental Information

Footnotes

1.  Carter, William P.L., Dongmin Luo, and Irina L. Malkina (1997). Investigation of the Atmospheric Ozone Formation Potential of T-Butyl Acetate, Report to ARCO Chemical Corporation, Riverside: College of Engineering Center for Environmental Research and Technology, University of California, 97-AP-RT3E-001-FR, http://www.cert.ucr.edu/​~carter/​pubs/​tbuacetr.pdf.

Back to Citation

2.  Between the EPA's proposed and final rule exempting TBAC as a VOC, the state of California raised concerns to the EPA about the potential carcinogenicity of tertiary-butanol, or TBA, the principal metabolite of TBAC. At the time, the EPA decided that there was insufficient evidence of health risks to affect the exemption decision, but persuaded LyondellBasell to voluntarily perform additional toxicity testing, use the testing results in a health risk assessment, and have the testing and assessment results reviewed in a peer consultation.

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3.  Toxicology Excellence for Risk Assessment (2009). Report of the Peer Consultation of the Potential Risk of Health Effects from Exposure to Tertiary-Butyl Acetate, January 7-8, 2009, Northern Kentucky University METS Center, Erlanger, Kentucky, Volumes I and II, http://www.tera.org/​Peer/​TBAC/​index.html.

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4.  Luo, Dongmin, et al. (2006) Environmental Impact Assessment of Tertiary-Butyl Acetate, Staff Report, Sacramento: California Environmental Protection Agency, Air Resources Board, January 2006, http://www.arb.ca.gov/​research/​reactivity/​tbacf.pdf http://www.arb.ca.gov/​research/​reactivity/​tbaca1.pdf http://www.arb.ca.gov/​research/​reactivity/​tbaca2.pdf.

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[FR Doc. 2015-02325 Filed 2-4-15; 8:45 am]

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