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Revisions to the California State Implementation Plan and Revision to the Definition of Volatile Organic Compounds (VOC)--Removal of VOC Exemptions for California's Aerosol Coating Products Reactivity- Based Regulation
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
[Federal Register: January 7, 2005 (Volume 70, Number 5)]
[Proposed Rules]
[Page 1639-1654]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr07ja05-34]
[[Page 1640]]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Parts 51 and 52
[OAR-2003-0200; FRL-7857-6]
Revisions to the California State Implementation Plan and
Revision to the Definition of Volatile Organic Compounds (VOC)--Removal
of VOC Exemptions for California's Aerosol Coating Products Reactivity-
Based Regulation
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
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SUMMARY: The EPA is proposing to approve a new consumer products
regulation as part of the California State Implementation Plan (SIP)
for ozone under the Clean Air Act (CAA) as amended in 1990. This
California regulation adopts an innovative approach to reduce ozone
formation from volatile organic compounds (VOC) in aerosol coating
products. The EPA is also proposing to approve the use of California's
Tables of Maximum Incremental Reactivity (MIR) to allow implementation
of the new regulation in California. We are also proposing to revise
EPA's definition of VOCs so that compounds which we previously
identified as negligibly reactive and exempt from EPA's regulatory
definition of VOCs will now count towards a product's reactivity-based
VOC limit for the purpose of California's aerosol coatings regulation.
We are taking comments on this proposal and we plan to follow with a
final action.
DATES: Comments must be received on or before March 8, 2005.
ADDRESSES: Submit your comments, identified by Docket ID No. OAR-2003-
0200, by one of the following methods:
? Federal eRulemaking Portal: http://www.regulations.gov. 
Follow the on-line instructions for submitting comments.
? Agency Web site: http://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: OAR Docket: OAR-2003-0200, Environmental Protection
Agency, Mailcode: 6102T, 1200 Pennsylvania Ave., NW., Washington, DC 20460.
? Hand Delivery: EPA/DC, Public Reading Room, Room B102, EPA
West Building, 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-2003-0200.
EPA's policy is that all comments received will be included in the
public docket without change and may be made available online at
http://www.epa.gov/edocket, including any personal information provided,
unless the comment includes information claimed to be Confidential
Business Information (CBI) or other information whose disclosure is
restricted by statute. Do not submit information that you consider to
be CBI or otherwise protected through EDOCKET, regulations.gov, or e-
mail. The EPA EDOCKET and the federal regulations.gov 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. For additional information about EPA's public
docket visit EDOCKET on-line or see the Federal Register of May 31,
2002 (67 FR 38102).
For additional instructions on submitting comments, go to Unit I of
the SUPPLEMENTARY INFORMATION section of this document.
Docket: All documents in the docket are listed in the EDOCKET index
at http://www.epa.gov/edocket. 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 OAR Docket, OAR-2003-0200, EPA/DC, EPA West, Room B102,
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 OAR Docket is (202)
566-1742.
FOR FURTHER INFORMATION CONTACT: Stanley Tong, Rulemaking Office (AIR-
4), Environmental Protection Agency, Region IX, 75 Hawthorne St., San
Francisco, CA 94105; telephone number: (415) 947-4122; fax number:
(415) 947-3579; e-mail address: tong.stanley@epa.gov.
SUPPLEMENTARY INFORMATION:
I. General Information
A. What Should I Consider as I Prepare My Comments for EPA?
1. Submitting 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 information in a disk or
CD ROM that you mail to EPA, mark the outside of the disk or CD ROM as
CBI and then identify electronically within the disk or CD ROM the
specific information that is claimed as CBI). In addition to one
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:
i. Identify the rulemaking by docket number and other identifying
information (subject heading, Federal Register date and page number).
ii. 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.
iii. Explain why you agree or disagree; suggest alternatives and
substitute language for your requested changes.
iv. Describe any assumptions and provide any technical information
and/or data that you used.
v. If you estimate potential costs or burdens, explain how you
arrived at your estimate in sufficient detail to allow for it to be
reproduced.
vi. Provide specific examples to illustrate your concerns, and
suggest alternatives.
vii. Explain your views as clearly as possible, avoiding the use of
profanity or personal threats.
[[Page 1641]]
viii. Make sure to submit your comments by the comment period
deadline identified.
ix. Please strictly limit comments to the subject matter of this
proposal, the scope of which is discussed below. Please identify the
section/subsection on which you are commenting so we can group similar
comments together and better understand the context of your comment.
x. EPA requests that you also send a copy of your comments to:
Andrew Steckel, Rulemaking Office Chief (AIR-4), U.S. Environmental
Protection Agency, Region IX, 75 Hawthorne Street, San Francisco, CA
94105-3901.
3. Docket Copying Costs. A reasonable fee may be charged for copying.
B. How Do I Request a Public Hearing?
If you wish to request a public hearing to submit comments
concerning this proposal please contact Mr. Stanley Tong, Rulemaking
Office (AIR-4), U.S. Environmental Protection Agency, 75 Hawthorne
Street, San Francisco, CA 94105, telephone (415) 947-4122. Requests for
a public hearing must be made by January 27, 2005. The EPA will publish
a notice of a hearing, if a hearing is requested, in the Federal
Register. Because the State has already held a public notice and
comment period for its aerosol coatings rule, any EPA hearing will be
strictly limited to the proposed EPA approval of the rule and its
inclusion in the California SIP and to the proposed change in the
definition of VOCs for 40 CFR 51.100(s). The hearing will not cover the
reactivity limits or other specifics of California's rule. If a public
hearing is requested, it will be held near our Region IX office in San
Francisco, CA.
C. Throughout This Document, ``We,'' ``Us'' and ``Our'' Refer to EPA
D. How Can I Get Copies of This Document and Other Related Information?
1. In addition to accessing the official public docket at http://
www.epa.gov/edocket/, you can also inspect copies of the submitted SIP
revision at our Region IX office during normal business hours. EPA
requests that you contact the person listed in the For Further
Information Contact section to schedule your inspection. You may also
see copies of the submitted SIP revision during normal business hours
by appointment at the California Air Resources Board, Stationary Source
Division, Rule Evaluation Section, 1001 ``I'' Street, Sacramento, CA 95814.
2. A copy of California's aerosol coating products regulation can
also be downloaded from the following internet addresses. Please be
advised that these are not EPA Web sites and may not contain the same
version of the regulations that were submitted to EPA.
http://www.arb.ca.gov/consprod/regs/aeropnt.pdf
http://www.arb.ca.gov/consprod/regs/Aeropnt.doc
Table of Contents
I. The State's Submittal.
A. What regulations did the State submit?
B. Are there other versions of this regulation?
C. What is the purpose of the submitted CARB regulation?
III. EPA's Evaluation and Action.
A. How is EPA evaluating the regulation?
B. Does the regulation meet the evaluation criteria?
C. Public comment and final action.
IV. Background Information.
A. Why was this regulation submitted?
B. What is photochemical reactivity?
C. Why is use of the relative reactivity concept appropriate in
California's aerosol coatings rule?
D. Are California's relative reactivity-based regulations
appropriate for areas outside of California?
E. How will the effectiveness of this reactivity-based program
be evaluated?
F. How has CARB addressed concerns about air toxics and ozone-
depleting substances?
G. What changes in enforcement strategies will likely occur due
to this relative reactivity-based regulation?
IV. Summary of CARB's Aerosol Coatings Regulation.
A. What does CARB's regulation require?
V. Future Actions.
A. What action will be taken to determine if this reactivity-
based regulation is effective?
B. How will future uses of relative reactivity be evaluated?
VI. Statutory and Executive Order Reviews.
I. The State's Submittal
A. What Regulations Did the State Submit?
Table 1 lists the regulations addressed by this proposal with the
date that they were adopted and submitted to EPA by the California Air
Resources Board (CARB).
Table 1.--Submitted Regulations
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Regulation title Adopted Submitted
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Aerosol Coating Products...................... 5/1/2001 3/13/2002
Tables of Maximum Incremental Reactivity (MIR) 5/1/2001 3/13/2002
Values.......................................
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On May 7, 2002, we found that this submittal meets the completeness
criteria in 40 CFR Part 51, Appendix V, as required before formal EPA
review.
B. Are There Other Versions of This Regulation?
There is no previous version of the aerosol coating products
regulation approved by EPA into the SIP, although CARB adopted an
earlier version of this regulation on March 23, 1995, and submitted it
to us on December 18, 1998. On November 19, 1998, CARB adopted
amendments to this earlier regulation. The CARB did not submit these
amendments to us as a SIP revision. There is no previous stand-alone
version of the Tables of MIR values in the SIP applicable to aerosol
coatings. Today, we are proposing approval of the CARB aerosol coatings
rule submitted to us on March 13, 2002. While we can act on only the
most recently submitted version of this regulation, we have reviewed
materials CARB provided with the previous SIP submittals for
informational purposes. Thus, this version of the aerosol coatings rule
replaces the earlier versions developed by CARB and, if we approve it,
will be the first such rule in the California SIP.
C. What Is the Purpose of the Submitted CARB Regulation?
The regulation covers aerosol coatings, aerosol clear coatings, and
aerosol stains. It applies to any person who sells, supplies, offers
for sale, applies, or manufactures for use in California any aerosol
coating subject to the limits in the regulation. The regulation imposes
reactivity-based VOC limits on these products for purposes of reducing
ozone caused by VOC emissions.
In the current SIP submittal, CARB has developed a new approach for
regulating VOC emissions from aerosol coatings. Traditionally, the VOC
emissions from aerosol and other coatings have been controlled by
limiting the mass of all VOCs in a product, and VOC content limits of
aerosol coatings were expressed as a maximum percent by mass of all
VOC. The new approach taken by CARB incorporates the concept of VOC
photochemical reactivity. This concept relies on the fact that the same
weight/amount of some VOCs (e.g., xylene) has the potential to form
more ozone, or to form ozone more quickly, than the same weight/amount
of other VOCs (e.g., propane) once they are emitted into the ambient
air under the same conditions.
The CARB estimates that its previous mass-based VOC control rule
for aerosol coatings resulted in statewide aerosol coating VOC
emissions reductions of 9
[[Page 1642]]
tons per day (tpd) from the 1989 baseline estimated VOC emissions of 30
tpd of VOC. The CARB calculates that the new reactivity-based aerosol
coatings rule in the current submittal would achieve the ``equivalent''
of an additional 3.1 tpd of VOC mass-based reductions statewide. In
other words, CARB estimates that this rule will achieve reactivity-
based VOC reductions that would be the equivalent of 12.1 tons of mass-
based VOC reductions from the 1989 baseline, measured in terms of ozone
reduction. The CARB intends its new regulation to encourage
manufacturers to reduce use of VOCs with higher reactivity, thereby
achieving more ozone reductions than through traditional VOC mass-based
regulations.
III. EPA's Evaluation and Action
A. How Is EPA Evaluating the Regulation?
Generally, SIP regulations must be enforceable (see section
110(a)(2)(A) of the CAA), must at a minimum require Reasonably
Available Control Technology (RACT) and Reasonably Available Control
Measures (RACM) in nonattainment areas (see, for example, sections
172(c)(1), 182(a)(2)(A) and 182(b)(2)), must not interfere with
attainment and reasonable further progress or any other applicable
requirement of the CAA, and must achieve the pollution reduction
requirements of the CAA (see section 110(l)). The CARB's aerosol
coatings regulation applies to both ozone attainment and non-attainment
areas statewide. Because this regulation covers nonmajor area sources
that are not covered by a Control Techniques Guidelines (CTG) document,
it is not subject to the RACT requirements for ozone nonattainment
areas (CAA, section 182(b)(2)).
Guidance and policy documents that we used to help evaluate
enforceability requirements includes: Issues Relating to VOC Regulation
Cutpoints, Deficiencies, and Deviations; Clarification to Appendix D of
November 24, 1987 Federal Register,'' (Blue Book), May 25, 1988,
(revised 1/11/90), Office of Air Quality Planning and Standards. We
also relied on several technical reports and journals to evaluate
CARB's SIP submittal. These reports and journals are referenced in
footnotes in the body of this proposal and are included in the docket
for this proposal.
B. Does the Regulation Meet the Evaluation Criteria?
We believe that the aerosol coatings rule will improve the SIP by
establishing stringent VOC limits for this product category, by
improving enforcement through labeling and reporting requirements, and
by creating an incentive for the use of solvents with relatively low
contribution to ozone formation. The regulation is generally consistent
with relevant policy and guidance regarding enforceability. Our
approval of the rule would also be consistent with CAA section 110(l),
because there is no prior version of the aerosol coatings regulation in
the SIP and ozone reductions resulting from the approval of this
regulation into the SIP will help in the State's efforts to achieve
attainment with the national ambient air quality standard (NAAQS) for
ozone. RACT requirements do not apply to the source category covered by
the CARB rule because RACT applies to major stationary sources in
nonattainment areas and source categories covered by a CTG. Because of
their widespread use in relatively small amounts, aerosol coatings are
considered area sources rather than major stationary sources. EPA has
not issued a CTG or a rule for this category. However, even though
federal RACT or consumer product requirements do not yet apply, CARB
took the initiative in 1995 to go beyond basic federally mandated VOC
reduction requirements by adopting an aerosol coatings regulation with
two tiers of aggressive mass-based VOC limits. In its current SIP
submittal, CARB is amending its existing regulation by replacing the
mass-based limits with reactivity-based limits intended to achieve
additional ozone reduction benefits.
Although CARB's existing mass-based aerosol coatings regulation has
significantly reduced emissions from aerosol coatings, CARB has
concluded that more reductions are needed to help reduce the high ozone
concentrations in Southern California and the Central Valley. The CARB
also believes that some VOC mass-based limits in the previous version
of the rule presented particularly difficult reformulation challenges
for manufacturers of water-based coatings,\1\ and the State concluded
that it may not be feasible to achieve additional VOC reductions from a
traditional VOC mass-based program. The current SIP submittal relies on
the relative reactivity concept, that is, the fact that individual
species of VOC react in the atmosphere to form different amounts of
ozone or to form ozone at different rates. The CARB hopes to target VOC
emission reductions to better control a product's contribution to ozone
formation by encouraging reductions of higher reactivity VOCs, rather
than by treating all VOCs in a product alike through a mass-based rule.
The submitted regulation therefore consists of reactivity-based limits
that replace the existing mass-based VOC limits for aerosol spray coatings.
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\1\ California Air Resources Board, ``Initial Statement of
Reasons for the Proposed Amendments to the Regulation for Reducing
Volatile Organic Compound Emissions from Aerosol Coating Products,''
Chapter VII, page 60, May 5, 2000.
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Although EPA is supportive of reactivity-based programs, we
recognize that they may be more complex to develop, enforce, and
evaluate than mass-based programs. As a result, it is particularly
important for us to evaluate the State agency's ability to implement
such programs. The CARB has addressed these concerns partly through an
extensive public process spanning over 3 years in the development of
the aerosol coatings rule. The CARB held eight public workshops and
over 20 meetings with industry, leading scientists, local air
districts, and EPA. The CARB also gathered detailed information on the
sales and composition of aerosol coatings, funded extensive research on
VOC reactivity scales and their applicability to environmental
conditions in California, and took steps intended to ensure that no
backsliding would occur from adoption of the relative-reactivity
approach. To account for potential changes in MIR values as scientific
knowledge improves, CARB also committed to improve and update its
program by including in its Board resolution \2\ the provision ``[t]o
review the Tables of Maximum Incremental Reactivity (MIR) Values 18
months after the effective date of the amendments, and every 18 months
thereafter, to determine if modifications to the MIR values are
warranted.'' The CARB will also ``[r]eview the reactivity-based limits
before January 1, 2007 to determine if modifications are necessary to
reflect changes to the MIR values and return to the Board with any
recommended modifications to the reactivity-based limits.'' \3\
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\2\ State of California Air Resources Board Resolution 00-22,
June 22, 2000, Agenda Item No. 00-6-1.
\3\ State of California Air Resources Board Resolution 00-22,
June 22, 2000, Agenda Item No. 00-6-1.
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Additional details about the comparison of reactivity-based
reductions to VOC mass-based reductions, the appropriateness of CARB's
reactivity research to areas outside of California, and the evaluation
of the effectiveness of CARB's regulation are provided in the
Background section below.
[[Page 1643]]
Information normally found in a Technical Support Document (TSD) is
incorporated into this proposed rule. A separate TSD has not been
written for this proposed rulemaking.
C. Public Comment and Final Action
Because EPA believes the submitted aerosol coatings regulation
fulfills all relevant requirements, we are proposing to approve it into
the California SIP as authorized in section 110(k)(3) of the CAA. We
are also proposing to approve the use of CARB's Tables of MIR values in
California for the purpose of implementation of the aerosol coatings
regulation. We intend to grant SIP credit for the ozone equivalent VOC
mass-based reductions that are achieved by CARB's reactivity-based
regulation. Details on the methodology CARB used to determine the
equivalent VOC mass-based tonnage reduction achieved by its reactivity
regulation is discussed in the CARB staff report.\4\
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\4\ California Air Resources Board, ``Initial Statement of
Reasons for the Proposed Amendments to the Regulation for Reducing
Volatile Organic Compound Emissions from Aerosol Coating Products,''
Chapter II, page 37, May 5, 2000.
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Currently, EPA's regulatory definition of VOC (40 CFR 51.100(s))
excludes certain compounds, such as methane and ethane, which EPA has
determined to have negligible photochemical reactivity with respect to
the formation of ozone. California's reactivity-based regulation,
however, requires the inclusion of the assigned MIR scale reactivity
value of each organic compound present in the volatile portion of a
product, even if the compound's reactivity value is so low that EPA has
previously determined it to be negligibly reactive and therefore exempt.
In order to approve CARB's aerosol coatings rule, EPA proposes to
modify our regulatory definition of VOC so that compounds previously
excluded will now be counted towards a product's reactivity-based VOC
limit for the limited purpose of CARB's aerosol coatings reactivity-
based regulation. Under 40 CFR 51.100(s), EPA has excluded compounds
from the definition of VOC in recognition of the fact that individual
organic compounds differ with respect to their incremental contribution
to ozone formation. EPA's exemption-based system separates organic
compounds into reactive and negligibly reactive compounds. The CARB's
reactivity-based regulation makes this distinction unnecessary because
CARB's rule assigns each compound a reactivity factor that accounts for
its relative contribution to ozone formation. These previously exempted
compounds will continue to be excluded from the Federal definition of
VOCs for other purposes.
We will accept comments from the public on this proposed approval
of the CARB aerosol rule into the SIP and the proposed modification of
our definition of VOC for the next 60 days. Unless we receive
convincing new information during the comment period, we intend to
publish a final approval action that will incorporate the regulations
listed in Table 1 into the federally enforceable SIP and modify our
definition of VOC to support CARB's aerosol coating rule.
The EPA, with CARB's assistance, intends to evaluate the
performance of this reactivity-based regulation in 3 years. This will
allow time to compile data on the implementation of, and compliance
with, the regulation, and will allow time to conduct additional
technical analysis such as modeling efforts needed to evaluate the
effect of the regulation on ambient ozone levels. We encourage CARB to
use this time to collect data on the costs and effectiveness of this
regulation, both to the regulated entities and to the regulators. In
particular, EPA is interested in how implementation of this regulation
affects the development of detailed emission inventories, as well as
industry compliance costs, including recordkeeping and compliance
testing, manufacturing or material costs, product quality and price.
Towards this goal, we are relying upon CARB's Board resolution \5\
which ``[d]irects the Executive Officer to take the following actions:
(1) Monitor the progress of manufacturers in meeting the reactivity-
based VOC limits, (2) propose any future regulatory modifications that
may be appropriate, and (3) continue to evaluate emerging technologies
for aerosol coatings to determine if additional ozone reductions will
be feasible in the future.''
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\5\ State of California Air Resources Board Resolution 00-22,
June 22, 2000, Agenda Item No. 00-6-1.
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The proposed approval of CARB's aerosol coatings regulation based
upon VOC reactivity is limited to this source category for this State.
EPA believes that relative reactivity-based regulations may help
provide the flexibility necessary to achieve further emissions
reductions from some source categories to address persistent ozone
nonattainment problems in areas of the country that need further
reductions in VOC emissions to come into attainment with federal ozone
standards. EPA is committed to continuing its support of research on
the suitability of relative reactivity-based regulations to other
geographic regions and to other source categories through the national
Reactivity Research Working Group (RRWG) of which CARB and EPA are
members.\6\ The purpose of the RRWG is to encourage and sponsor
research on scientific questions concerning VOC reactivity which may be
of interest to regulators. This group is affiliated with NARSTO
(formerly known as the North American Research Strategy for
Tropospheric Ozone) and is a voluntary organization currently composed
of industry, government and academic representatives. The group has an
open membership and anyone may attend the meetings and participate.
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\6\ See ``VOC Reactivity'' at http://www.cgenv.com/Narsto/.
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The EPA is specifically seeking public comment on how reactivity-
based programs might affect industry compliance and recordkeeping costs
to support effective implementation and enforcement, and how industry
and regulatory agency costs and staff requirements might change with
respect to emission inventories.
We are not seeking comments on the reactivity limits or other
specifics of CARB's rule; nor are we seeking comments on EPA's VOC
exemption process. The EPA has previously published in 63 FR 48792
(September 11, 1998) its views on reactivity as it relates to the
regulation of VOC emissions from consumer products pursuant to CAA
Sec. 183(e) and this proposal should not be construed as a change in
the Agency's interpretation of that provision. When commenting, please
indicate which section of this proposal you are commenting on so we can
group similar comments together.
III. Background Information
A. Why Was This Regulation Submitted?
Ground level ozone, commonly referred to as ``smog,'' is a serious
air pollutant that harms human health and the environment. Ground level
ozone is a complex problem that is difficult to control in part because
ozone is not emitted directly by specific sources. It forms in the air
when there are chemical reactions between nitrogen oxides
(NOX) and VOCs in the presence of heat and sunlight.
Therefore, one way to reduce ozone levels in many areas is to control
emissions of VOCs. Section 110(a) of the CAA requires States to submit
regulations that control VOC emissions as part of the State's SIP.
B. What Is Photochemical Reactivity?
There are thousands of individual species of VOC chemicals that can
[[Page 1644]]
combine with NOX and the energy from sunlight to form ozone.
The impact of a given VOC on formation of ground-level ozone is
sometimes referred to as its ``reactivity.'' It is generally understood
that not all VOCs are equal in their effects on ground-level ozone
formation. Some VOCs react extremely slowly and changes in their
emissions have limited effects on ozone pollution episodes. Some VOCs
form ozone more quickly, or they may form more ozone than other VOCs.
Others not only form ozone themselves, but also enhance ozone formation
from other VOCs. By distinguishing between more reactive and less
reactive VOCs, however, it should be possible to decrease ozone
concentrations further or more efficiently than by controlling all VOCs
equally.
Assigning a value to the reactivity of a compound is not
straightforward. Reactivity is not simply a property of the compound
itself; it is a property of both the compound and the environment in
which the compound is found. The reactivity of a single compound varies
with VOW-NOX ratios, meteorological conditions, the mix of
other VOCs in the atmosphere, and the time interval of interest.
Designing an effective regulation that takes account of these
interactions is difficult, and implementing and enforcing such a
regulation carries the extra burden of characterizing and tracking the
full chemical composition of VOC emissions.
1. History of EPA's VOC Policy
Historically, EPA's general approach to regulation of VOC emissions
has been based upon control of total VOCs by mass, without
distinguishing between individual species of VOC. EPA considered the
regulation of VOCs by mass to be the most effective and practical
approach based upon the scientific and technical information available
when EPA developed its VOC control policy.
EPA issued the first version of its VOC control policy in 1971, as
part of EPA's SIP preparation guidance.\7\ In that guidance, EPA
emphasized the need to reduce the total mass of VOC emissions, but it
also suggested that substitution of one compound for another might be
useful when it would result in a clearly evident decrease in reactivity
and thus tend to reduce photochemical oxidant formation. This latter
statement encouraged States to promulgate SIPs with VOC emission
substitution provisions similar to the Los Angeles County Air Pollution
Control District's (LACAPCD) Rule 66,\8\ which allowed some VOCs that
were believed to have low to moderate reactivity to be exempted from
control. The exempt status of many of those VOCs was questioned a few
years later, when research results indicated that, although some of
those compounds do not produce much ozone close to the source, they may
produce significant amounts of ozone after they are transported
downwind from urban areas.\9\
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\7\ U.S. Environmental Protection Agency. ``Requirements for
Preparation, Adoption, and Submittal of Implementation Plans.''
Federal Register, 36 FR 15486-15506 (1971).
\8\ County of Los Angles, Air Pollution Control District (1972).
Rules and Regulations. Rule 66 (1966). Amended November 2, 1972.
\9\ Dimitriades, B. ``Oxidant/03 Air Quality Benefits from
Emission Substitution.'' In: ``Proceedings. Hydrocarbon Control
Feasibility. Its Impact on Air Quality'' (and references herein).
Speciality Conference, Air Pollution Control Association, April, 1977.
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In 1977, this research led EPA to issue the second version of its
VOC policy under the title ``Recommended Policy on Control of Volatile
Organic Compounds,'' (42 FR 35314, July 8, 1977) offering its own, more
limited list of exempt organic compounds. The 1977 policy identified
four compounds that have very low photochemical reactivity and
determined that their contribution to ozone formation and accumulation
could be considered negligible. The policy exempted these ``negligibly
reactive'' compounds from VOC emissions limitations in programs
designed to meet the ozone NAAQS. Since 1977, the EPA has added other
compounds to the list of negligibly reactive compounds based on new
information as it has been developed. In 1992, the EPA adopted a formal
regulatory definition of VOC for use in SIPs, which explicitly excludes
compounds that have been identified as negligibly reactive [40 CFR
51.100(s)]. To date, EPA has exempted 53 compounds or classes of
compounds in this manner.
In effect, EPA's current VOC exemption policy has resulted in a
two-bin system in which most compounds are treated equally as VOCs and
are controlled and a separate smaller group of compounds are treated as
negligibly reactive and are exempt from VOC control.\10\ This approach
was intended to encourage the reduction of emissions of all VOCs that
participate in ozone formation. From one perspective, it appears that
this approach has been relatively successful. EPA estimates that,
between 1970 and 2003, VOC emissions from man-made sources nationwide
have declined by 54 percent. This decline in VOC emissions has helped
to decrease average ozone concentration by 29 percent (based on 1-hour
averages) and 21 percent (based on 8-hour averages) between 1980 and
2003. These reductions have occurred even though, between 1970 and
2003, population, vehicle miles traveled, and gross domestic product
have risen 39 percent, 155 percent and 176 percent respectively.
[Latest Findings on National Air Quality: 2002 Status and Trends, EPA
454/K-03-001, August 2003; and The Ozone Report Measuring Progress
through 2003, EPA 454/K-04-001, April 2004; Environmental Protection
Agency, Office of Air Quality Planning and Standards, Research Triangle
Park, North Carolina]
---------------------------------------------------------------------------
\10\ It should be noted that EPA has also taken VOC reactivity
into consideration in other ways, such as the development of the
consumer and commercial product regulations under CAA Sec. 183(e).
EPA considered VOC reactivity as a factor in developing the federal
consumer products program as directed by the statute, and EPA's
approach was confirmed by the courts. See, Allied Local & Regional
Mfrs. Caucus v. EPA, 215 F.3d 61 (D.C. Cir. 2000), cert. denied 532
U.S. 1018 (2001). The EPA plans to develop its own regulation for
aerosol coating products under CAA Sec. 183(e). Our future
regulation may differ from CARB's regulation. If this turns out to
be the case, a process will need to be developed to verify that the
State's requirements and limits are at least as stringent as those
in the national standard.
---------------------------------------------------------------------------
On the other hand, some have argued that a reactivity-based
approach for reducing VOC emissions would be more effective than the
current mass-based approach. One group of researchers conducted a
detailed modeling study of the Los Angeles area and concluded that,
compared to the current approach, a reactivity-based approach could
achieve the same reductions in ozone concentrations at significantly
less cost--or for a given cost, could achieve a significantly greater
reduction in ozone concentrations.\11\ EPA recognizes that, in theory,
a well designed reactivity-based program, in which each individual VOC
is regulated more or less stringently based on its actual contribution
to ozone formation, would be more efficient than the current approach.
On the other hand, there are significant practical difficulties
involved in designing, implementing, and enforcing such a program. We
believe that the CARB program we are proposing to approve today will
help EPA and other States to evaluate whether the benefits of a
reactivity-based approach are sufficient to outweigh these practical
difficulties.
---------------------------------------------------------------------------
\11\ A. Russell, J. Milford, M. S. Bergin, S. McBride, L.
McNair, Y. Yang, W. R. Stockwell, B. Croes, ``Urban Ozone Control
and Atmospheric Reactivity of Organic Gases,'' Science, 269: 491-
495, (1995).
---------------------------------------------------------------------------
We also recognize that, in spite of the progress that most parts of
the country
[[Page 1645]]
have made in reducing ozone concentrations, further reductions in VOC
emissions will likely be needed to bring a number of areas into
attainment with the 8-hour ozone standard. In particular, in areas
where significant VOC emission controls are already in place, further
mass-based emission reductions may be difficult or very expensive to
achieve. In such situations, regulations that distinguish between
individual VOCs and create an incentive to shift production and use
from more reactive VOCs to less reactive VOCs may provide the
flexibility necessary to continue progress towards attainment of the
ozone NAAQS.
2. History of CARB's Reactivity Work
Regulatory authorities in California have been experimenting with
the concept of reactivity-based regulations for some time. The first
regulation in California that took reactivity into account was Rule
66,\12\ adopted in the mid 1960s by LACAPCD. This rule restricted
emissions of certain classes of compounds which were defined by the
rule as photochemically reactive based on their chemical structure
(e.g., compounds having olefinic type of unsaturation) to 40 pounds per
day, but allowed up to 3000 pounds per day emissions for many other
organic compounds which were not defined by the rule as photochemically
reactive. In other words, Rule 66 sought to regulate certain VOCs more
than others, based on the assumption that some VOCs participate more in
ozone formation. Rule 66 was very influential at the time and versions
of it were adopted by several other States. However, the VOC control
approach taken by Rule 66 has been superseded by EPA's definition of
VOC (57 FR 3941, February 3, 1992), which was based on the 1977 EPA
policy statement and which only exempted a smaller number of negligibly
reactive compounds.
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\12\ The South Coast Air Quality Management District (SCAQMD),
the successor agency to LACAPCD, renamed this Rule 442.
---------------------------------------------------------------------------
Like EPA's 1977 policy, Rule 66 was really a ``two bin'' system
which tightly controlled certain compounds, which were defined as more
photochemically reactive, and applied a much lesser level of control to
a large class of compounds, which were regarded as less reactive. The
main difference between Rule 66 and the later EPA VOC definition
approach was the criteria for classifying compounds as exempt (or
subject to lesser control), with the EPA definition allowing a much
smaller group of compounds to be considered non-reactive or exempt.
In 1991 California adopted regulations intended to differentiate
between species of VOC based upon a reactivity scale, instead of a two
bin system. The 1991 rules were the Low-Emission Vehicles and Clean
Fuels regulations that CARB intended to reduce VOC emissions by mass
from motor vehicles generally, but which also took into account VOC
reactivity differences in organic gas when comparing the emissions from
alternatively fueled vehicles (AFVs).\13\ \14\ Although not a full-
blown attempt to regulate VOCs by their relative reactivity, CARB
nonetheless began the exploration of the MIR scale as a mechanism to
distinguish between VOCs and encourage reduction of more reactive VOCs.
---------------------------------------------------------------------------
\13\ California Air Resources Board ``Proposed Regulations for
Low-Emission Vehicles and Clean Fuels-Staff report and Technical
Support Document,'' State of California, Air Resources Board,
Sacramento, CA, August 13, 1990.
\14\ California Air Resources Board ``Proposed Regulations for
Low-Emission Vehicles and Clean Fuels-Final Statement of Reasons,''
State of California, Air Resources Board, July, 1991.
---------------------------------------------------------------------------
Today's proposal addresses CARB's most recent effort to utilize the
concept of VOC relative reactivity and the MIR scale to regulate VOC
emissions. This rule reflects a major shift from the traditional mass-
based control strategies for reduction of VOC emissions and introduces
this concept in a far more significant way than in CARB's previous
actions. In connection with the SIP submittal for this aerosol coatings
rule, CARB has provided additional supporting information in the form
of journal articles and reports which describe VOC reactivity research
efforts.
3. What Research Has Been Conducted in Reactivity?
Much of the work on reactivity scales that CARB used as a basis for
its aerosol coatings rule was done at the University of California at
Riverside by William P. L. Carter. Carter investigated 18 different
ozone reactivity scales.\15\ All of these scales are based on chamber
studies intended to evaluate the impact of a given VOC on ozone
formation under certain assumed conditions. The three most prominent
scales he developed were:
---------------------------------------------------------------------------
\15\ Carter, William P. L., ``Development of Ozone Reactivity
Scales for Volatile Organic Compounds,'' J. Air & Waste Manage.
Assoc., 44: 881-899, (1994).
---------------------------------------------------------------------------
i. Maximum Incremental Reactivity (MIR) scale--an ozone yield scale
derived by adjusting the NOX emissions in a base case to
yield the highest incremental reactivity of the base reactive organic
gas mixture.\16\
---------------------------------------------------------------------------
\16\ The CARB's reactivity regulation defines the term Reactive
Organic Compound (ROC) as any compound that has the potential, once
emitted to contribute to ozone formation in the troposphere. ROCs
include compounds which are excluded from EPA's definition of VOCs
as found in 40 CFR 51.100(s).
---------------------------------------------------------------------------
ii. Maximum Ozone Incremental Reactivity (MOIR) scale--an ozone
yield scale derived by adjusting the NOX emission in a base
case to yield the highest peak ozone concentration.
iii. Equal Benefit Incremental Reactivity (EBIR) scale--an ozone
yield scale derived by adjusting the NOX emissions in a base
case scenario so VOC and NOX reductions are equally
effective in reducing ozone.
In addition to Carter's work, there have been other attempts to
create reactivity scales. One such effort is the work of R. G. Derwent
and M. E. Jenkins, who have published articles on a scale called the
photochemical ozone creation potential (POCP) scale.\17\ This scale was
derived for the conditions prevalent in Europe. The POCP scale is
roughly consistent with those of Carter although, as expected, there
are some differences because the POCP scale is based on European conditions.
---------------------------------------------------------------------------
\17\ See, for example, R. G. Derwent and M.E. Jenkin,
``Hydrocarbons and the Long-Range Transport of Ozone and PAN Across
Europe,'' Atmospheric Environment, 25A, No. 8, 1661-1678, (1991).
---------------------------------------------------------------------------
The CARB has relied most heavily on Carter's research for its
regulatory development and CARB has used the MIR scale for development
of the aerosol coating regulation.\18\ The MIR scale is designed using
certain assumptions about meteorological and environmental conditions
where ozone production is most sensitive to changes in hydrocarbon
emissions and, therefore, is intended to represent conditions where VOC
emission controls will be most effective. The MIR scale is expressed as
grams of ozone formed per gram of organic compound reacted. Each
compound is assigned an individual MIR value, which enables the
reactivities of different compounds to be compared quantitatively.
Individual MIR values now exist for many commonly used compounds, and a
list of these individual values comprises a scale.
---------------------------------------------------------------------------
\18\ California Air Resources Board, ``Initial Statement of
Reasons for the Proposed Amendments to the Regulation for Reducing
Volatile Organic Compound Emissions from Aerosol Coating Products,''
Chapter II, page 12, May 5, 2000.
---------------------------------------------------------------------------
To evaluate reactivity scales and ensure that VOC reactivity is
used appropriately in its proposals, CARB created the Reactivity
Scientific Advisory Committee (RSAC), a group of leading researchers in
the field of atmospheric science. This group reviews CARB's reactivity
related work
[[Page 1646]]
and convenes periodically in meetings which are open to the public to
comment on CARB's work.
The EPA has been closely following the scientific literature on
reactivity scales, and is interested in how such reactivity scales
might be applied to national programs or programs in other States.
Because reactivity depends on the characteristics of the environment as
well as the compound, scales are developed to represent a particular
set of environmental conditions in certain geographic locations. It is
not clear whether a single scale can represent actual ozone formation
over the whole country where meteorological and environmental
conditions vary considerably. Many scales, including the MIR scale are
derived for ozone formed during one day of reaction time. The EPA is
interested in whether such scales adequately represent the ozone
formation from VOCs during multi-day stagnation events or long-range
transport of pollutants, in such places as those seen in the Northeast
section of the country, which may take place over several days.
To help answer such questions, EPA and CARB are participating in
the RRWG, which sponsored three atmospheric photochemical modeling
studies to examine how changing the reactivity of the mix of VOC
emissions might affect ozone formation across wide geographical areas
over time. The three areas that researchers studied were the Houston
area, North Carolina, and the eastern half of the United States. The
EPA anticipates that these three studies and follow-up efforts will
help to answer many questions about the potential use of relative
reactivity in developing, implementing, and enforcing VOC regulatory
programs.
C. Why Is Use of the Relative Reactivity Concept Appropriate in
California's Aerosol Coatings Rule?
There are five classes of nonattainment for the 1-hour ozone
standard, ranging from marginal to extreme. The Los Angeles--South
Coast Air Basin Area and the San Joaquin Valley--San Joaquin Valley Air
Basin in California are currently the only areas in the nation in the
worst category of extreme nonattainment (40 CFR 81.305 and 69 FR
20550). Under the 8-hour standard, there are no areas classified under
the ``extreme'' ozone non-attainment category. South Coast is
classified as severe non-attainment and San Joaquin is classified as
serious non-attainment under the 8-hour standard. Because of the
elevated ozone levels in Los Angeles, the San Joaquin Valley and
elsewhere in California, CARB has adopted many innovative rules and
regulations to help reduce ozone precursor emissions. These efforts
include adopting regulations which go beyond current federally-mandated
VOC reduction requirements, such as regulating a wider variety of area
and mobile sources and establishing aggressive emission standards that
force development of new low-emission technologies.
As one such effort, CARB already adopted a statewide regulation in
1995 limiting the VOC mass content of 35 categories of aerosol
coatings. This regulation contained two tiers of VOC limits and a
provision to extend the compliance deadline for up to 5 years for each
aerosol coating category if it was determined that the limits were not
feasible. On November 19, 1998, CARB amended the regulation to relax
the limits for 12 coating categories after determining that the
original limits were not feasible even with the 5-year extension. CARB
made limits for 11 other categories more stringent. The CARB also
extended the compliance date to January 1, 2002, for all 35 product
categories covered by the aerosol coating rule to provide time for
manufacturers to comply with the new limits.
In the current SIP submittal, CARB has determined that even with
the extended compliance date, some of the VOC content limits remain
technologically challenging. In order to preserve the air quality
benefits of its 1998 rule, while at the same time allowing
manufacturers greater flexibility in reformulating their products, CARB
is replacing its pre-existing mass-based VOC limits for aerosol spray
coatings with reactivity-based limits that are designed to achieve
equivalent air quality benefits. The CARB's explicit goal was to
develop reactivity-based limits that would ensure that the ozone
reduction commitment from its second tier mass-based VOC limits would
not be compromised.\19\ For the reasons set forth below, EPA believes
that CARB's amended aerosol spray coating regulation achieves this goal.
---------------------------------------------------------------------------
\19\ California Air Resources Board, ``Initial Statement of
Reasons for the Proposed Amendments to the Regulation for Reducing
Volatile Organic Compound Emissions from Aerosol Coating Products,''
Executive Summary, page 2, May 5, 2000.
---------------------------------------------------------------------------
1. Equivalency of Air Quality Benefits
i. Sufficient information about the source category. In order to
determine equivalent ozone reductions and set appropriate limits, CARB
collected detailed product speciation information and sales data from
manufacturers. For the aerosol coatings category, CARB found that over
80 percent of the species of VOCs typically used as ingredients were
well-studied and an additional 17 percent of the species typically used
would need only minor adjustment for uncertainty in their MIR values.
In other words, CARB concluded that the reactivity values of over 95
percent of the VOCs generally used in the specific category of aerosol
coatings were fairly well-studied and understood.\20\ The accuracy and
completeness of the VOC inventory, and the availability of
scientifically reviewed and published reactivity values for those VOCs
used in aerosol coatings may not be available for other consumer
product categories. The CARB's reactivity regulation defines the term
``reactive organic compound'', or ``ROCs,'' as any compound that has
the potential, once emitted, to contribute to ozone formation in the
troposphere. The ROCs include compounds which EPA has excluded from the
regulatory definition of VOCs found in 40 CFR 51.100(s). To minimize
confusion to the reader, we will continue to use the term ``VOC'' in
the remainder of this proposal, instead of ``ROC.'' When the term
``VOC'' is used in the context of CARB's reactivity-based aerosol
coatings rule, the reader should remember that this refers to all VOCs,
including those compounds that are excluded from EPA's regulatory
definition of VOC. The accurate identification and measurement of
individual VOC compounds and development of accurate MIR values is
crucial to the effectiveness of a reactivity program.\21\
---------------------------------------------------------------------------
\20\ California Air Resources Board, ``Initial Statement of
Reasons for the Proposed Amendments to the Regulation for Reducing
Volatile Organic Compound Emissions from Aerosol Coating Products,''
Chapter IV, page 36, May 5, 2000.
\21\ B.J. Finlayson-Pitts, J.N. Pitts Jr, ``Atmospheric
Chemistry of Tropospheric Ozone Formation: Scientific and Regulatory
Implications,'' J. Air Waste Manage. Assoc. 43:1091-1100, (1993).
---------------------------------------------------------------------------
ii. Sufficient information about the reactivity scale and its
applicability to California. In conjunction with this SIP submittal,
CARB provided a listing of approximately 50 research articles to help
support its conclusion that this aerosol coatings regulation based upon
VOC relative reactivity is appropriate for conditions in California and
that the MIR scale chosen by CARB is the most appropriate scale for
this regulation.
As stated earlier, CARB relies on the work of Carter in the
development of the scale for the aerosol coatings rule. Carter
investigated 18 different ozone reactivity scales and concluded
``[t]hat the MIR scale (or a scale similar to it,
[[Page 1647]]
such as one based on integrated ozone over the standard) is appropriate
for regulatory applications where a reactivity scale is required.''
\22\ He determined that, while different reactivity scales might give
different reactivity orderings of VOCs, for most VOC species the
general rankings among the different scales were very similar. He also
found that even relatively large variations in the base ROG mixture
\23\ had, in most cases, only a small effect on relative reactivity.
For example, a two-fold increase in the amount of aromatics in the base
mixture of VOCs in the chamber study resulted in less than a 20 percent
change in the relative MIR reactivity. From this it could be inferred
that significant changes in the ambient mixture of VOCs in the
atmosphere would not significantly change the relative MIR value.
---------------------------------------------------------------------------
\22\ W.P.L. Carter, ``Development of Ozone Reactivity Scales for
Volatile Organic Compounds,'' J. Air Waste Manage. Assoc. 44:881-
899, (1994).
\23\ From Carter's article on ``Development of Ozone Reactivity
Scales for Volatile Organic Compounds,'' the term ``base ROG
mixture'' means the mixture of Reactive Organic Gases (ROGs)
initially present or emitted in the Empirical Kinetic Modeling
Approach (EKMA) scenarios except for biogenic VOCs, VOCs present
aloft, or VOCs added for the purpose of calculating their
incremental reactivities.
---------------------------------------------------------------------------
The various studies conducted to date show good agreement in
reactivity values for most VOC species between normalized reactivity
scales generated by airshed models and Carter's box-modeled
calculations. For example, Bergin et al.,\24\ summarized a number of
papers comparing reactivity scales predicted by airshed models to those
predicted by Carter using a box-model. Most of the papers are based on
simulations conducted with the Carnegie Mellon/California Institute of
Technology model (CIT) for Los Angeles using the ozone episode of
August 27-29, 1987. Bergin reports that airshed model-derived spatially
weighted results behave similarly to MIRs.\25\ The report further
states that the greatest differences were found for formaldehyde and
other compounds whose reactivities were highly dependent on photolytic
reactions, and in general, airshed model results for Los Angeles agree
well with MIRs, and further show that individual organics have very
different ozone formation impacts.
---------------------------------------------------------------------------
\24\ M. Bergin, W.P.L. Carter, J. Milford, P.J. Ostrowski, A.G.
Russell, Reactivity Assessments, Reactivity Research Working Group
(May 5, 1999).
(ftp://ftp.cgenv.com/pub/downloads/RRWGdoc/assess-2.pdf).
\25\ M. Bergin, W.P.L. Carter, J. Milford, P.J. Ostrowski, A.G.
Russell, Reactivity Assessments, Reactivity Research Working Group,
Page 12, (May 5, 1999).
(ftp://ftp.cgenv.com/pub/downloads/RRWGdoc/assess-2.pdf).
---------------------------------------------------------------------------
While Bergin's reactivity assessment indicates a general support
for the concept of relative reactivity, she also points out that gaps
exist in the current knowledge base of the scientific community and
points to areas where further investigation is needed. For example,
Bergin acknowledges that although airshed model results for Los Angeles
agree well with MIRs, such a study has not been conducted for other
regions. Also, Bergin suggested that additional work is needed to
examine the effects of aromatics under several different conditions,
and that Eastern transport conditions should also be examined in a
multi-day scenario. The RRWG is currently reviewing studies which
examine the reactivities in the eastern half of the United States which
will help to answer some of these questions.
Similarly, recent work by Martien and Harley found that ``[f]or
most species studied'' * * * ``[r]eactivity scales developed by 3-D
modeling resulted in similar rankings of individual VOC when compared
to reactivity scales developed by Carter using a box model.'' \26\ They
also point out that ``[S]ite-to-site differences (in reactivity values)
can be large when absolute reactivity scales are considered. The
variation in reactivity across sites is reduced when reactivity is
measured on a relative rather than absolute scale. Differences in
relative reactivity may still occur as a function of location, with
differences likely to be magnified where absolute reactivities are low.''
---------------------------------------------------------------------------
\26\ P. Martien, R.Harley, ``Development of Reactivity Scales
via 3-D Grid Modeling of California Ozone Episodes,'' Final report
prepared for California Air Resources Board, May 2002.
---------------------------------------------------------------------------
One study submitted by CARB to EPA attempts to address the issue of
whether the MIR scale adequately represents VOC reactivity in transport
scenarios. Kaduwela and his associates \27\ assessed for the first time
whether box-model based scales are applicable to regional-scale
domains, which include transport of pollutants through urban and rural
areas. They did this by conducting grid-based photochemical simulations
in a regional domain in central California for five compounds and found
a linear correlation between box-model based scales and regional grid-
based scales. These studies indicate a correlation between box-model
scales used in Carter's work and the more detailed scales. Therefore,
CARB concludes that the box-model's lack of physical detail and shorter
episode time does not limit the suitability of the MIR values with
respect to concerns about transport within California.
---------------------------------------------------------------------------
\27\ A. Kaduwela, V. Hughes, L. Woodlouse, P. Allen, J. DaMassa,
A. Ranzieri, ``Photochemical Reactivity of Organic Compounds in
Central California: A Grid-Based Modeling Study,'' Presented at
Stanford University, CA July 26-28, 1999.
---------------------------------------------------------------------------
During an October 1999 RSAC meeting, a member of the public asked
the RSAC whether the scenarios used to calculate MIRs are realistic.
The RSAC committee ``[r]esponded that the relative reactivity doesn't
change between scenarios and that, in a study which examined an
exposure metric calculated by a 3-D model, the relative reactivities
correlated well with MIRs.'' \28\ At the same meeting, a member of the
public also asked the RSAC if MIR conditions were appropriate for
California. The committee's response was that whether MIR conditions
were appropriate for California was a policy decision. The CARB's SIP
submittal states \29\ that ``[w]hile the MIR scale has been extensively
tested as appropriate for use in California, we caution that our
research has focused on California atmospheric conditions only. As
such, the suitability of using the MIR scale for regulatory purposes in
other parts of the United States has not been demonstrated, and may not
be appropriate.''
---------------------------------------------------------------------------
\28\ Minutes of the Reactivity Scientific Advisory Committee,
October 8, 1999,
http://www.arb.ca.gov/research/reactivity/rsac/oct99-min.html.
\29\ State Implementation Plan (SIP) Submittal letter from
Michael Kenny (CARB) to Wayne Nastri (US EPA, Region IX), March 13, 2002.
---------------------------------------------------------------------------
iii. Approach to Uncertainty. Although the MIR values are
calculated with what a peer reviewed report \30\ describes as a
``state-of-the-science'' chemical mechanism, the reactivity values of
some VOCs are still uncertain,\31\ while those of other VOCs have been
more thoroughly studied and will not likely change with further
research. To account for this uncertainty, CARB has applied Carter's
uncertainty ranking which defines 6 categories or ``bins'' to describe
the ``certainty'' of the chemical mechanism used to determine the MIR
values. The uncertainty scale is subjective, but it is described as
Carter's best judgment of the certainty scientists currently have of an
organic compound's chemical
[[Page 1648]]
reaction mechanism and its effect on that compound's estimated MIR
value \32\. If the MIR value of a compound is relatively certain or if
there are some uncertainties but the MIR value is not expected to
change significantly, the compound is assigned to bin one. If the
current mechanism is probably incorrect and biases in atmospheric
reactivity predictions are uncertain, the compound is assigned to bin
six. When calculating an equivalent ozone reduction, CARB identifies
which of the 6 bins a compound is in, and then multiplies the
compound's MIR value with a factor of between 1 and 2 to compensate for
the uncertainty of that MIR value. The uncertainty factors associated
with each bin were developed by CARB with input from Carter. The CARB
applies an uncertainty factor of 1.0 to compounds classified within
uncertainty bins one and two; a factor of 1.25 to compounds in bin
three; a factor of 1.5 to compounds in bin four; and a factor of 2.0
for compounds in bins five and six. For certain hydrocarbon solvents
defined under the regulation, CARB uses an uncertainty factor of 1.15.
The CARB also developed a methodology for those compounds used in
aerosol coatings that did not have published MIR values. The
methodology, which was reviewed by the RSAC, provides an estimate for
the presumed upper limit MIR value. No adjustment factor is applied to
the upper limit MIRs as the method infers the highest reactivity of the
chemical.\33\
---------------------------------------------------------------------------
\30\ W.R. Stockwell, ``Review of the Updated Maximum Incremental
Reactivity Scale of Dr. William Carter,'' Prepared for the
California Air Resources Board, Page 151, November 29, 1999--A copy
can be found in section 4N of CARB's SIP submittal for this rule.
\31\ California Air Resources Board, ``Initial Statement of
Reasons for the Proposed Amendments to the Regulation for Reducing
Volatile Organic Compound Emissions from Aerosol Coating Products,''
Chapter II, Page 13, May 5, 2000.
\32\ W.R. Stockwell, ``Review of the Updated Maximum Incremental
Reactivity Scale of Dr. William Carter,'' Prepared for the
California Air Resources Board, Page 122, November 29, 1999--A copy
can be found in section 4N of CARB's SIP submittal for this rule.
\33\ California Air Resources Board, ``Initial Statement of
Reasons for the Proposed Amendments to the Regulation for Reducing
Volatile Organic Compound Emissions from Aerosol Coating Products,''
Chapter IV, pages 32-37, May 5, 2000.
---------------------------------------------------------------------------
Other researcher 34 35 36 looking into the aspects of
uncertainties in chemical reaction rate parameters, used in the model
to calculate MIRs, believe that the uncertainties in the chemical rate
parameters have directionally similar effects on the reactivities of
most compounds. That is, if compound ``a'' had a higher reactivity
value than compound ``b,'' then after taking into account the
uncertainties in their chemical rate parameters, compound ``a'' would
generally still have a higher reactivity value than compound ``b.''
These researchers conclude that the significance of these uncertainties
could be minimized by using reactivities in a relative sense, as CARB
has done in this rule.
---------------------------------------------------------------------------
\34\ Y. Yang, W.R. Stockwell, J.B. Milford, ``Uncertainties in
Incremental Reactivities of Volatile Organic Compounds,'' Environ.
Sci. Technol., 29, 1336-1345, (1995).
\35\ M.S. Bergin, A.G. Russell, J.B. Milford, ``Effects of
Chemical Mechanism Uncertainties on the Reactivity Quantification of
Volatile Organic Compounds Using a Three-Dimensional Air Quality
Model,'' Environ. Sci. Technol., 32, 694-703, (1998).
\36\ N.L. Kelly, T.Y. Chang, ``An experimental Investigation of
Incremental Reactivities of Volatile Organic Compounds,''
Atmospheric Environment, 33, 2101-2110, (1999).
---------------------------------------------------------------------------
iv. Do Federal VOC exemptions apply to CARB's program?
Because CARB's regulation attempts to account for the actual
contribution to ozone formation by each organic compound, it does not
exempt any reactive compounds, including those that EPA has exempted
from the definition of VOC pursuant to 40 CFR 51.100(s). In order to
get a more accurate calculation of a product's impact on ozone
formation, CARB uses the assigned reactivity value of each compound,
however high or low its MIR value. Therefore, compounds such as
acetone, which are excluded from EPA's definition of VOCs in 40 CFR
51.100(s), are counted towards the compliance limit under CARB's
reactivity-based regulation.
v. No backsliding. In developing the proposed reactivity limits,
one of CARB's goals was to ensure that the ozone reduction commitment
from the existing mass-based VOC limits for aerosol spray coatings
would not be compromised. In certain situations, however, a reactivity-
based regulation could result in increased ozone concentrations over a
traditional VOC mass-based regulation. For instance, because the MIR
scale is based on a 1-day simulation, during a multi-day episode, a
manufacturer could substitute the proper amount or too much of a lower
reacting compound for a higher reacting one and thereby increase ozone
formation over longer periods of time.
While we believe there are circumstances under which ozone
formation could potentially increase because of use of reactivity-based
VOC limits, we also recognize that the same unintended consequences can
occur with current mass-based VOC rules. The CARB reported \37\ that
one company intended to comply with stricter CARB VOC mass-based limits
by using less total VOC, but also by increasing the amount of much more
reactive VOCs to compensate for solvency needs in the product. The CARB
also reported that another large company indicated that its compliance
strategy with more stringent VOC mass limits would be to increase the
aromatic content (increasing reactivity) in its products. In these
instances, CARB points out that the increased reactivity of the VOC
emissions likely reduces the benefits of the lower mass of VOC
emissions. There is no evidence to suggest, however, that regulated
entities will always choose to use smaller amounts of higher reactivity
compounds in place of lower reactivity compounds when a product's mass-
based VOC limit is reduced. In any event, it is impossible to predict
whether the use of smaller amounts of more reactive VOCs will result in
more ozone without knowing how the identity and proportions of the
other VOC ingredients in the product will change. While we acknowledge
that there is the potential for this unintended consequence of mass-
based controls, we generally believe that achieving significant mass
reductions of VOCs is directionally correct in most situations. As
noted above, however, EPA believes that reactivity-based approaches
such as the one developed by CARB may be a promising alternative to
mass-based approaches in some cases where additional VOC controls are
necessary.
---------------------------------------------------------------------------
\37\ California Air Resources Board letter from Michael Kenny to
Deborah Jordan, U.S. EPA, Region IX, dated July 24, 2000.
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Revisions to the SIP should contribute to progress towards reaching
attainment with the NAAQS and not relax emission standards or retreat
from emission reduction goals already achieved. Towards these goals,
CARB has assured EPA that there will be no backsliding as a result of
the use of the relative reactivity approach. With assistance from CARB,
EPA intends to monitor the effectiveness of the aerosol coatings rule
to ensure that the rule obtains the intended and required reductions in
ambient ozone levels.
2. Evaluation and Revision
The development, maintenance, evaluation, and revision of a
reactivity-based VOC regulation requires significant resources and
technical expertise. The CARB's commitment to the reactivity concept is
evidenced by funding, between 1989 to the present, over $4,000,000
worth of research on reactivity related projects including modeling,
chemical mechanism development, atmospheric chemistry and VOC speciation.
Similarly, we believe that additional resources and technical
expertise are needed to implement and enforce a reactivity-based
regulation than for a traditional mass-based regulation. For example,
under a mass-based VOC regulation, analysis of a coating to
[[Page 1649]]
determine compliance largely requires simply determining the weight
difference of a sample before and after heating it in an oven \38\.
This testing is relatively easy and inexpensive, thereby facilitating
enforcement by the regulating authority or others.
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\38\ See 40 CFR 60, appendix A Reference Method 24.
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In contrast, determining compliance of the same product with a
reactivity-based regulation is more complex and consequently more
expensive. Here, the laboratory needs to identify and quantify each
individual VOC present in the sample, possibly with multiple gas
chromatography with mass spectrometry (GC/MS) runs. In order to
determine compliance, the regulatory agency then must multiply the
concentration of each compound in the aerosol coating by its MIR value
and then sum the results to determine the product's total MIR value. In
some cases, the MIR values for isomers of compounds are different, such
as for ortho, meta and para xylenes (MIR = 7.49, 10.61, and 4.25
respectively). Speciation of isomers increases the complexity of the
analysis. In addition, the identification of hydrocarbon solvents by
boiling point range and aromatic content will add an additional step to
the analysis. The CARB laboratory staff routinely uses GC/MS techniques
to analyze products for a relatively small number of compounds excluded
from EPA's regulatory definition of VOC which may be in consumer
products, so CARB has some experience with these analytical techniques.
Further, CARB is ``[f]ully prepared to vigorously enforce this
regulation'' and their ``[e]nforcement inspectors and laboratory staff
have expertise and resources to collect and test aerosol coating
products to verify compliance with the regulation.'' \39\
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\39\ State Implementation Plan submittal letter from Michael
Kenny (CARB) to Wayne Nastri (U.S. EPA, Region IX), March 13, 2002.
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Because any complex regulation can potentially multiply the
opportunities for non-compliance, whether intentional or inadvertent,
EPA believes that an intensive program to monitor and enforce
compliance is a critical element to any VOC reactivity-based regulation.
D. Are California's Relative Reactivity-Based Regulations Appropriate
for Areas Outside of California?
1. The CARB's technical support for this program in California does
not necessarily demonstrate that VOC reactivity-based programs would be
appropriate or effective in other areas or for other regulatory
programs. The CARB's SIP submittal cautions that its research has
focused only on California atmospheric conditions and that the
suitability of the MIR scale for regulatory purposes in other areas has
not been demonstrated. The CARB further states \40\ that VOC relative
``[r]eactivity needs to be examined for the rest of the country.'' and
that they ``[s]upport these investigations and plan to continue CARB's
participation in the RRWG.''
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\40\ State Implementation Plan Submittal letter from Michael
Kenny (CARB) to Wayne Nastri (US EPA Region IX), March 13, 2002.
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EPA is aware that only recently has there been published,
coordinated scientific research to attempt to address questions
concerning the use of VOC reactivity-based regulations in other
locations. For example, a recent NARSTO report describes limitations to
ozone control using a VOC reactivity-based approach. The NARSTO report
suggested that the approach might only be effective when the ambient
conditions are ``[V]OC limited and where natural hydrocarbon emissions
are not dominant.'' \41\ In addition, the NARSTO report states that
``[t]he reactivity of specific VOCs can change from locale to locale,
and thus the specifics of the approach must be regionally tailored.''
As noted earlier, the RRWG has sponsored a series of recent studies
exploring these issues.
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\41\ The NARSTO, An Assessment of Tropospheric Ozone Pollution--
A North American Perspective, page 3-19, July 2000.
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One of the concerns with the representativeness of MIR values is
that they are based on a model which simulates reactions over a single
day and may not account for slower reacting compounds which might
continue to form ozone over several days. These slower reactions could
result in more ozone formation than is predicted by the MIR scale in
areas experiencing multi-day stagnation events or increased ozone
formation in downwind areas due to pollutant transport.
The MIR scale is basically a reduced-form model, or a model of a
model, which attempts to characterize in a single number the relative
contribution of individual compounds to the formation and accumulation
of ozone in a complex atmospheric system. Thus, a particular chemical
mechanism and set of assumed environmental conditions are implicit in
the MIR scale. The purpose of comparing the MIR scale to reactivities
calculated using an airshed model is to evaluate whether the MIR scale,
as a reduced-form model, adequately represents the behavior of the more
complex airshed model, which takes into account spatially and
temporally varying meteorology and emissions. If comparisons show a
disagreement between the MIR values and the airshed derived values,
that may suggest that it may not be appropriate to try to capture the
behavior of the system in the single scale. If comparisons do show an
agreement, this would suggest that the MIR scale can reproduce the
behavior of the complex system, at least for the set of conditions
considered.
Several researchers have performed such comparisons, including
Bergin, Derwent and Stockwell. Bergin et al.,\42\ calculated reactivity
values using a more detailed three-dimensional photochemical model and
compared their results against the values calculated by the simpler
model used to develop CARB's reactivity program for their alternative
fuels program. Bergin found that results were well correlated between
Carter's simpler model and their more detailed model. However, these
researchers also found that toluene, ethylbenzene, two xylene species,
and some aldehydes had lower reactivity values predicted by the more
detailed model as compared to the simpler model. Bergin concluded that
differences in the predicted reactivity values were possibly due to
multi-day simulation periods and the inclusion of cloud cover by the
more detailed model.
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\42\ M.S. Bergin, A.G. Russell, J.B. Milford, ``Quantification
of Individual VOC Reactivities Using a Chemically Detailed, Three-
Dimensional Photochemical Model,'' Environ. Sci. Technol., 29, 3029-
3037, (1995).
---------------------------------------------------------------------------
Derwent \43\ also reports that single-day or multi-day conditions
appear to be important in establishing quantitative reactivity scales
for the less reactive organic compounds. Stockwell,\44\ who completed
the peer review of Carter's reactivity mechanism, states that single-
day scenarios are used to calculate incremental reactivities by
definition, but even relatively unreactive organic compounds may have a
non-negligible effect on ozone concentrations if multiple-day scenarios
are considered. When he calculated incremental reactivities for
multiple-days for polluted European conditions, he found that ethane's
MIR value increased over 6 times from a MIR value of 0.19 on the first
day to 1.17 on the 6th day. He also found that Dimethyoxymethane's MIR
[[Page 1650]]
value increased as the length of the simulation period increased.
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\43\ R.G. Derwent, M.E. Jenkin, S.M. Saunders, M.J. Pilling,
``Characterization of the Reactivities of Volatile Organic Compounds
Using a Master Chemical Mechanism,'' J. Air and Waste Manage.
Assoc., 51, 699-707, (2001).
\44\ W.R. Stockwell, H. Geiger, K.H. Becker, ``Estimation of
Incremental Reactivities for Multiple Day Scenarios: An Application
to Ethane and Dimethyoxymethane,'' Atmospheric Environment, 35, 929-
939, (2001).
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While we are uncertain whether results based on European conditions
might generally apply to conditions found in California or the United
States, these studies raise two questions. First, is the increase in
MIR values during a multi-day stagnation event mainly a concern for
slower reacting compounds or a more widespread issue, and second,
should any changes be made to MIR scale values to account for the
apparent increases in reactivity values in multi-day stagnation
scenarios. Additional research may be needed in this area to understand
more fully the impacts of multi-day scenarios on relative reactivity
values and the prevalence of transport and multi-day stagnation
conditions on a regional scale within California's ozone nonattainment
areas and ozone nonattainment areas in other parts of the country.
While we have some concerns about the greater level of effort required
to develop, implement, and enforce reactivity-based programs, we
believe that California has the resources and technical expertise
needed to develop and maintain a complex program such as this one.
E. How Will the Effectiveness of This Reactivity-Based Program Be
Evaluated?
1. We plan to evaluate the effectiveness of the aerosol coatings
rule in 3 years. Areas we may review include changes in the composition
and quantity of VOC emissions, which would require establishing a
baseline of current emissions.
2. We are also interested in evaluating changes in ambient air
quality that result from the use of the relative reactivity approach in
this rule. We recognize that currently available computer models have
limitations in their ability to evaluate the actual ambient effects of
reducing emissions of specific VOC species from a particular product
category. Also, while it is possible to show an air quality benefit of
substituting individual VOCs with lower reactivity for more reactive
ones using a three-dimensional photochemical model, it is not clear
that current photochemical modeling systems are adequate to predict the
impacts of the wide variety of simultaneous substitutions that may
occur under an MIR-weighted regulatory program. The EPA, with CARB's
assistance, plans to investigate possible modeling enhancements to
evaluate the effects of the aerosol coatings rule, and hopes to
identify modeling ``experiments'' to further test the MIR's predictive
performance.
While a VOC reactivity-based regulation may result in a more
efficient regulation in terms of more flexible reformulation options
for manufacturers and an additional control strategy to reduce
tropospheric ozone, we are also interested in how costs under a
reactivity-based regulation might change for monitoring and
recordkeeping. Under a reactivity-based program, emission inventory
efforts may increase for industry periodically to provide fully
speciated product information and for regulatory agencies to input this
information into emission inventory data bases. We are interested in
the public's comment on how the industry's and regulatory agency's
costs and staff requirements might change with respect to emission
inventories.
3. As stated earlier, CARB intends to keep up to date on VOC
reactivity research through a review of the MIR values every 18 months
and a review of the reactivity limits before January 1, 2007.
F. How Has CARB Addressed Concerns About Air Toxics and Ozone-Depleting
Substances?
The CARB's aerosol coatings regulation prohibits the use of three
toxic air contaminants: Methylene chloride, perchloroethylene and
trichloroethylene. While the regulation does not ban the use of other
compounds listed as ``hazardous air pollutants'' that are commonly used
in aerosol coatings such as xylene and toluene, CARB believes that
emissions of these other toxic compounds are likely to be reduced
through the overall emission limits imposed on the individual product
categories. Regulated entities will have an incentive to use less of
compounds like toluene and xylene because of their higher reactivity,
and this will outweigh the interest in choosing VOCs based solely upon
their cost.
The CARB's regulation also prohibits the sale, supply, application,
or manufacture for use in California, of any aerosol coating product
which contains a stratospheric ozone-depleting substance. Existing
product formulations which contain an ozone-depleting substance that
complies with the reactivity limits and was sold in California during
1997 or product formulations containing an ozone-depleting substance
that was sold in California during 1997 that is reformulated to meet
the reactivity limits, as long as the content of the ozone-depleting
substances in the reformulated product does not increase, are exempted
from this provision.
G. What Changes in Enforcement Strategies Will Likely Occur Due to This
Relative Reactivity-Based Regulation?
1. How will testing for compliance change under CARB's aerosol
coatings regulation? As discussed earlier, under a traditional mass-
based regulation, analysis of a coating to determine compliance is
performed using EPA Reference Method 24.\45\ This method involves
heating the sample in an oven and determining the weight difference of
the sample before and after heating. Additional analysis is needed to
account for the propellant and, if present in the sample, compounds
which are excluded from EPA's definition of VOCs. Under a mass-based
rule, the laboratory does not need to know which individual
hydrocarbons are present in order to perform Method 24, other than to
identify if a limited number of excluded compounds are present in the
coating. Manufacturers are generally willing to reveal the proportions
of exempt substances because that helps to demonstrate compliance with
the mass-based VOC limits.
---------------------------------------------------------------------------
\45\ See 40 CFR 60, appendix A, Reference Method 24.
---------------------------------------------------------------------------
Determining compliance under a reactivity-based regulation is more
complex, but still within the capabilities of CARB's laboratory.
Specifically, the regulator must perform expensive and complex GC/MS
analysis to identify and quantify each VOC present in the product in
order to calculate the product weighted MIR. To facilitate this
compliance determination, CARB's aerosol coatings rule allows CARB to
request manufacturers to provide a listing of the VOCs and their
concentrations in each product so the laboratory knows which VOCs to
analyze for and their target concentrations. While laboratories could
perform the analysis without such a listing, it would be substantially
more difficult, time-consuming, and expensive. This increased
difficulty in assuring compliance is among the reasons that EPA is
concerned that CARB allocate sufficient resources to monitor and
enforce the reactivity-based limits.
2. How does a reactivity regulation affect the availability of
emissions data? In the past, determining compliance with emission
limits under a mass-based VOC rule such as CARB's aerosol coatings rule
did not raise concerns about confidential business information (CBI)
because one could determine compliance with the product's VOC limit
without ever having to know all of the individual VOC ingredients present
[[Page 1651]]
in the product. However, under a reactivity-based rule, one would need
to know the specific VOCs in a product and their proportions (i.e., the
product formulation) in order to determine compliance with its
reactivity-based VOC limit. Because this information is an integral
part of determining compliance with the product's reactivity-based
limit, the list of VOCs would be considered ``emissions data,'' which
must generally be available to the public.\46\ However, industry may
view the release of such detailed VOC information to the general public
or to their business competitors as a major concern because of the
potential for release of trade secrets and propriety CBI.
---------------------------------------------------------------------------
\46\ Emissions data is defined in 40 CFR 2.301(a)(2)(i).
---------------------------------------------------------------------------
To help resolve these competing issues, we note that aerosol
coatings are composed of a VOC portion and a portion made up of various
non-reactive compounds such as resins and solids which, based on CARB's
aerosol coatings regulation, do not contribute to ozone formation and
are assigned an MIR value of zero. Consistent with section 114(c) of
the CAA, and our regulations concerning the release of emissions data
at 40 CFR Sec. 2.301, we believe the public's right to emissions data
is satisfied by assuring access to the portion of the data which
comprises the VOCs alone. Information on the non-reactive compounds,
i.e., those that do not contribute to ozone formation, would not need
to be released, thereby preserving potential trade secrets.
The CARB and the aerosol coatings industry held discussions and
reached an agreement that CARB VOC testing results and company-supplied
formulation data required to be submitted by Section 94526 of CARB's
aerosol coatings regulation would be made available to the public, upon
request, to allow others to verify compliance with the reactivity-based
aerosol coating regulation. It was further agreed that non-reactive
compounds in each product formulation would be ``lumped'' or aggregated
to protect confidentiality.\47\
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\47\ The CARB letter from Michael Kenny to Jack Broadbent, U.S.
EPA, Region IX, dated May 16, 2002.
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Both CARB and EPA will retain their authority to access all
ingredient information, including non-VOC ingredients or information
otherwise claimed to be CBI, in order to determine compliance with the
regulation.
The availability to the public of VOC ingredient information
constituting emissions data only applies to information gathered to
confirm compliance with CARB's aerosol coatings rule. Confidential
information such as survey data submitted by companies under Section
94524 of CARB's aerosol coatings regulation to CARB and EPA in support
of any future rule development efforts, will continue to be handled in
accordance with applicable CBI regulations.
We believe that this compromise between the competing objectives of
disclosure of emissions data and protection of CBI provides a basis for
approving CARB's innovative reactivity-based regulation into the SIP.
We also believe that the compromise is consistent with the purpose of
CAA Sec. 114(c) and EPA's regulations defining emissions data.
IV. Summary of CARB's Aerosol Coatings Regulation
A. What Does CARB's Regulation Require?
The CARB has previously controlled VOC emissions from aerosol
coatings in California by limiting the mass of VOCs in the product,
with limits expressed as maximum allowable percent by mass of VOC.
CARB's new approach relies on the fact that individual VOCs may form
different amounts of ozone, or form ozone more quickly, once they are
emitted into the air. The CARB is implementing a regulation that would
limit ozone formation by taking into account the relative reactivity of
different VOC ingredients.
The CARB's aerosol coatings regulation contains sections on
applicability, definitions, limits and requirements, exemptions,
administrative requirements, variances, test methods, Federal
enforceability and references tables of MIR values for different
compounds including hydrocarbon solvents.
1. What Does CARB's Aerosol Coatings Regulation Cover?
This section contains a very brief summary of key portions of
CARB's regulation. The reader should refer to the actual regulation
\48\ for additional details.
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\48\ http://www.arb.ca.gov/consprod/regs/aeropnt.pdf
http://www.arb.ca.gov/consprod/regs/Aeropnt.doc or California
Code of Regulations, Title 17, Division 3, Chapter 1, Subchapter 8.5,
Article 3.
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The regulation applies to aerosol coatings, aerosol clear coatings
and aerosol stains. It applies to any person who sells, supplies,
offers for sale, applies or manufactures for use in California any
aerosol coating subject to the limits in the regulation. The regulation
prohibits the commercial application of non-complying aerosol coating
products.
The regulation does not apply to aerosol lubricants, mold releases,
automotive underbody coatings, electrical coatings, cleaners, belt
dressings, anti-static sprays, layout fluids and removers, adhesives,
maskants, rust converters, dyes, inks, and leather preservatives or
cleaners. The regulation also does not apply to aerosol coating
products manufactured in California for shipment and use outside of
California.
Aerosol coating products manufactured beginning June 1, 2002, for
general coating categories as defined in the regulation and January 1,
2003, for specialty coatings need to comply with the reactivity-based
VOC limits specified in the regulation. Aerosol products manufactured
before the effective dates must comply with the existing mass-based VOC
limits. However, products labeled with the applicable reactivity-based
VOC limit, must meet that limit. The regulation contains a sell-through
provision whereby products manufactured prior to the effective date can
be sold, supplied, offered for sale, or applied up to 3 years after the
effective date.
The regulation prohibits the use of the toxic air contaminates
methylene chloride, trichloroethylene, and perchloroethylene. It also
prohibits the use of stratospheric ozone-depleting substances in
aerosol coating products except in limited situations allowed by the
regulation.
The regulation contains labeling and reporting requirements, and
provisions for a regulated entity to request a variance from the VOC
reactivity limits if the entity cannot comply due to extraordinary
reasons beyond reasonable control. The test method section specifies
that CARB Method 310 is to be used to determine compliance with the
regulation. Alternative test methods may be used which are shown to
identify and quantify accurately each ingredient, after approval in
writing by the CARB Executive Officer. However, as stated in the
aerosol coatings regulation,\49\ for purposes of Federal
enforceability, EPA is not bound by approval determinations made by the
CARB Executive Officer for variances or test methods. While EPA
believes CARB would not approve major test method modifications that
might compromise the integrity of a test result, or grant a variance
request that would adversely
[[Page 1652]]
impact an approved attainment demonstration, EPA can pursue separate
action to ensure that test results are enforceable, accurate, and
reproducible, and that a variance does not adversely impact attainment.
---------------------------------------------------------------------------
\49\ California Code of Regulations, Title 17, Division 3,
Chapter 1, Subchapter 8.5, Article 3, Sec. 94528.
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Variances and major modifications to test methods must be submitted
to EPA and must be approved into the SIP before they can be Federally
enforceable. For the purposes of Federal enforceability, facilities
operating under a variance or modified test method approved by the CARB
Executive Officer must continue to comply with the original regulation
until the variance or major test method modification is also approved
by EPA into the SIP. The EPA does not normally approve Executive
Officer discretion in regulations submitted for SIP approval as this
would allow potentially significant modifications to a regulation or
test method without subsequent review and approval by EPA.
We are proposing to approve this Executive Officer provision in
this rule because this is a new and innovative program and, as such,
may require a temporary variance or an unanticipated modification to
the test method in the short term, and the regulation states that EPA
is not bound by the decisions of the Executive Officer. The EPA intends
to monitor CARB's implementation of these rule provisions and we will
review test method modifications and variance requests on a case-by-
base basis.
V. Future Actions
A. What Action Will Be Taken To Determine if This Reactivity-Based
Regulation Is Effective?
The EPA will continue to work with CARB to evaluate how VOC
emissions from this source category change in response to the
regulation and how these emission changes will affect ambient air
quality. We will also continue to work with CARB to evaluate the
appropriateness of MIR values for VOC reactivity ranking under the
environmental conditions of interest in California. The EPA's proposed
approval of CARB's aerosol coatings regulation is predicated, in part,
on CARB's commitment to ensuring that the regulation in fact achieves
the intended environmental goals. The CARB's SIP submittal letter \50\
states that CARB officials ``[i]ntend to follow the implementation of
this regulation closely to ensure the air quality benefits predicted
are fully achieved. If they are not, CARB is obligated to identify and
secure additional regulatory measures to meet our SIP commitments.''
``[M]oreover, if in fact the aerosol coating regulation is not as
effective as predicted, we are fully prepared to reevaluate the source
category to determine how best to achieve the most stringent limits
that are technologically and commercially feasible.''
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\50\ SIP submittal letter from Michael Kenny (CARB) to Wayne
Nastri (U.S. EPA, Region IX), March 13, 2002.
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B. How Will Future Uses of Relative Reactivity Be Evaluated?
The CARB views the aerosol coatings rule as a means to determine
the feasibility of additional reactivity-based measures for other
source categories.\51\ The EPA is working as a participant in the RRWG
to explore whether reactivity-based approaches are appropriate and
useful for other source categories and in other parts of the country.
Members of the RRWG have a variety of research projects underway to
provide needed information about the utility and effectiveness of
relative reactivity-based VOC controls. The EPA is committed to the
process begun under the RRWG of assuring that future applications of
the relative reactivity approaches are based on a sound scientific
foundation and are practical, enforceable, and effective.
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\51\ California Air Resources Board, ``Initial Statement of
Reasons for the Proposed Amendments to the Regulation for Reducing
Volatile Organic Compound Emissions from Aerosol Coating Products,''
Chapter II, page 18, May 5, 2000.
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VI. Statutory and Executive Order Reviews
A. Executive Order 12866: Regulatory Planning and Review
Under Executive Order 12866, (58 FR 51735, October 4, 1993) the
Agency must determine whether the regulatory action is ``significant''
and therefore subject to the Office of Management and Budget (OMB)
review and the requirements of the Executive Order. The Order defines
``significant regulatory action'' as one that is likely to result in a
rule that may:
(1) Have an annual effect on the economy of $100 million or more or
adversely affect in a material way the economy, a sector of the
economy, productivity, competition, jobs, the environment, public
health or safety, or State, local, or tribal governments or communities;
(2) Create a serious inconsistency or otherwise interfere with an
action taken or planned by another agency;
(3) Materially alter the budgetary impact of entitlements, grants,
user fees, or loan programs or the rights and obligations of recipients
thereof; or
(4) Raise novel legal or policy issues arising out of legal
mandates, the President's priorities, or the principles set forth in
the Executive Order.
For the change in definition of VOCs, EPA has determined that this
proposed rule is not a ``significant regulatory action'' under the
terms of Executive Order 12866 and is therefore not subject to OMB
review. For the proposed approval of CARB's rule into the SIP, OMB has
exempted this regulatory action from Executive Order 12866 review.
B. Paperwork Reduction Act
For the change in the definition of VOCs, this proposed rule does
not contain any information collection requirements subject to OMB
review under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq.
For the proposed approval of CARB's regulation into the SIP, this
proposed action does not contain any information collection
requirements that would require any person to provide information to
EPA, however CARB's regulation contains requirements for the aerosol
coating industry to provide information to CARB.
C. Regulatory Flexibility Act (RFA)
The RFA generally requires an agency to prepare a regulatory
flexibility analysis of any rule subject to notice and comment
rulemaking requirements under the Administrative Procedure Act or any
other statute unless the agency certifies that the rule will not have a
significant economic impact on a substantial number of small entities.
Small entities include small businesses, small organizations, and small
governmental jurisdictions.
After considering the economic impacts of today's proposed rule on
small entities, I certify that this action will not have a significant
economic impact on a substantial number of small entities.
This proposed rule will not impose any requirements on small
entities. Today's change to the definition of VOC does not directly
regulate any entities. The RFA analysis does not consider impacts on
entities which the action in question does not regulate. See Motor &
Equipment Manufacturers Ass'n v. Nichols, 142 F. 3d 449, 467 (D.C. Cir.
1998); United Distribution Cos. v. FERC, 88 F. 3d 1105, 1170 (D.C. Cir.
1996), cert. denied, 520 U.S. 1224 (1997).
For the proposed approval of CARB's regulation into the SIP, this
proposed rule will not have a significant impact on a substantial
number of small entities because SIP approvals under section 110 and
subchapter I, part D of the CAA
[[Page 1653]]
do not create any new requirements but simply act on requirements that
the State is already imposing. Therefore, because the Federal SIP
approval does not create any new requirements, I certify that this
action will not have a significant economic impact on a substantial
number of small entities.
Moreover, due to the nature of the Federal-State relationship under
the CAA, preparation of flexibility analysis would constitute Federal
inquiry into the economic reasonableness of State action. The CAA
forbids EPA to base its actions concerning SIPs on such grounds. Union
Electric Co. v. U.S. EPA, 427 U.S. 246, 255-66 (1976); 42 U.S.C.
7410(a)(2).
D. Unfunded Mandates Reform Act
Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public
Law 104-4, establishes requirements for Federal agencies to assess the
effects of their regulatory actions on State, local, and tribal
governments and the private sector. Under section 202 of UMRA, EPA
generally must prepare a written statement, including a cost-benefit
analysis, for proposed and final rules with ``Federal mandates'' that
may result in expenditures by State, local, and tribal governments, in
the aggregate, or the private sector, of $100 million or more in any 1
year. Before promulgating an EPA rule for which a written statement is
needed, section 205 of UMRA generally requires EPA to identify and
consider a reasonable number of regulatory alternatives and adopt the
least costly, most cost-effective or least burdensome alternative that
achieves the objectives of the rule. The provisions of section 205 do
not apply when they are inconsistent with applicable law. Moreover,
section 205 allows EPA to adopt an alternative other than the least
costly, most cost-effective or least burdensome alternative if the
Administrator publishes with the final rule an explanation why that
alternative was not adopted. Before EPA establishes any regulatory
requirements that may significantly or uniquely affect small
governments, including tribal governments, it must have developed under
section 203 of UMRA a small government agency plan. The plan must
provide for notifying potentially affected small governments, enabling
officials of affected small governments to have meaningful and timely
input in the development of EPA regulatory proposals with significant
Federal intergovernmental mandates, and informing, educating, and
advising small governments on compliance with the regulatory requirements.
For the proposed change in the definition of VOCs, today's
rulemaking contains no Federal mandates (under the regulatory
provisions of title II of the UMRA) for State, local, or tribal
governments or the private sector.
For the proposed approval of CARB's regulation into the SIP, EPA
has determined that the proposed approval action does not include a
Federal mandate that may result in estimated costs of $100 million or
more to either State, local, or tribal governments in the aggregate, or
to the private sector. This Federal action proposes to approve pre-
existing requirements under State or local law, and imposes no new
requirements. Accordingly, no additional costs to State, local, or
tribal governments, or to the private sector, result from this action.
Thus, today's rule is not subject to the requirements of sections
202 and 205 of UMRA.
In addition, EPA has determined that this rule contains no
regulatory requirements that might significantly or uniquely affect
small governments in accordance with section 203 of UMRA.
E. Executive Order 13132: Federalism
Executive Order 13132, entitled ``Federalism'' (64 FR 43255, August
10, 1999), requires EPA to develop an accountable process to ensure
``meaningful and timely input by State and local officials in the
development of regulatory policies that have federalism implications.''
``Policies that have federalism implications'' is defined in the
Executive Order to include regulations that have ``substantial direct
effects on the States, on the relationship between the national
government and the States, or on the distribution of power and
responsibilities among the various levels of government.''
This proposed rule does not have federalism implications. It will
not have substantial direct effects on the States, on the relationship
between the national government and the States, or on the distribution
of power and responsibilities among the various levels of government,
as specified in Executive Order 13132. Today's proposed rule does not
impose any new mandates on State or local governments. The change to
the definition of VOCs merely assists CARB in implementing its aerosol
coatings reactivity regulation. The proposed approval of this
regulation into the SIP acts on a State regulation implementing a
Federal standard, and does not alter the relationship or the
distribution of power and responsibilities established in the CAA.
Thus, Executive Order 13132 does not apply to this rule.
In the spirit of Executive Order 13132, and consistent with EPA
policy to promote communications between EPA and State and local
governments, EPA specifically solicits comment on this proposed rule
from State and local officials.
F. Executive Order 13175: Consultation and Coordination With Indian
Tribal Governments
Executive Order 13175, entitled ``Consultation and Coordination
with Indian Tribal Governments'' (59 FR 22951, November 9, 2000),
requires EPA to develop an accountable process to ensure ``meaningful
and timely input by tribal officials in the development of regulatory
policies that have tribal implications.'' This proposed rule does not
have tribal implications, as specified in Executive Order 13175. The
proposed change to the definition of VOCs merely assists CARB in
implementing its aerosol coatings reactivity regulation and does not
impose any direct compliance costs. The proposed approval of CARB's
regulation into the SIP acts on a State regulation and does not alter
the relationship between the Federal government and Indian Tribes, as
specified in Executive Order 13175. Thus, Executive Order 13175 does
not apply to this rule. The EPA specifically solicits additional
comment on this proposed rule from tribal officials.
G. Executive Order 13045: Protection of Children From Environmental
Health and Safety Risks
Executive Order 13045: ``Protection of Children from Environmental
Health and Safety Risks'' (62 FR 19885, April 23, 1997) applies to any
rule that: (1) Is determined to be ``economically significant'' as
defined under Executive Order 12866, and (2) concerns an environmental
health or safety risk that EPA has reason to believe may have a
disproportionate effect on children. If the regulatory action meets
both criteria, the Agency must evaluate the environmental health or
safety effects of the planned rule on children, and explain why the
planned regulation is preferable to other potentially effective and
reasonably feasible alternatives considered by the Agency.
While this proposed rule is not subject to the Executive Order
because it is not economically significant as defined in Executive
Order 12866, we have reason to believe that ozone has a
disproportionate effect on active children who play outdoors. (See 62
FR 38856 and 38859 July 18, 1997). However, we do not expect today's
proposed approval of CARB's regulation into the SIP to result in an
adverse
[[Page 1654]]
impact, as it is intended to be an ozone neutral action. The CARB has
indicated that they have designed their new reactivity-based limits to
achieve the same ozone reductions as the mass-based limits they
supplant. Also, we do not expect today's proposed change to the
definition of VOC to result in any adverse impact, because it increases
the number of compounds subject to regulation as VOCs for the purpose
of California's aerosol coatings reactivity-based regulation.
H. Executive Order 13211: Actions That Significantly Affect Energy
Supply, Distribution, or Use
This rule is not subject to Executive Order 13211, ``Actions That
Significantly Affect Energy Supply, Distribution, or Use'' (66 FR 28355,
May 22, 2001) because it is not a significant regulatory action under
Executive Order 12866.
I. National Technology Transfer Advancement Act
Section 12(d) of the National Technology Transfer Advancement Act
of 1995 (``NTTAA''), Public Law No. 104-113, Sec. 12(d) (15 U.S.C. 272
note) directs EPA to use voluntary consensus standards in its
regulatory activities unless to do so would be inconsistent with
applicable law or otherwise impractical. Voluntary consensus standards
are technical standards (e.g., materials specifications, test methods,
sampling procedures, and business practices) that are developed or
adopted by voluntary consensus standards bodies. The NTTAA directs EPA
to provide Congress, through OMB, explanations when the Agency decides
not to use available and applicable voluntary consensus standards.
For the change in definition of VOCs, this proposed rulemaking does
not involve technical standards. Therefore, EPA is not considering the
use of any voluntary consensus standards. For the proposed approval of
CARB's regulation into the SIP, the State regulation references
standard test methods and makes modifications to American Society for
Testing and Materials (ASTM) D3074-94, D3063-94 and D2879-97 to support
the regulatory objectives.
The EPA welcomes comments on this aspect of the proposed rulemaking
and, specifically, invites the public to identify potentially-
applicable voluntary consensus standards and to explain why such
standards should be used in this regulation.
List of Subjects
40 CFR Part 51
Environmental protection, Administrative practice and procedure,
Air pollution control, Carbon monoxide, Intergovernmental relations,
Lead, Nitrogen dioxide, Ozone, Particulate matter, Reporting and
recordkeeping requirements, Sulfur oxides, Volatile organic compound.
40 CFR Part 52
Environmental protection, Air pollution control, Intergovernmental
relations, Ozone, Reporting and recordkeeping requirements, Volatile
organic compound.
Authority: 42 U.S.C. 7401 et seq.
Dated: December 29, 2004.
Michael O. Leavitt,
Administrator.
PART 51--REQUIREMENTS FOR PREPARATION, ADOPTION, AND SUBMITTAL OF
IMPLEMENTATION PLANS.
1. The authority citation for part 51 continues to read as follows:
Authority: 42 U.S.C. 7401, 7411, 7412, 7413, 7414, 7470-7479,
7501-7508, 7601, and 7602.
2. Section 51.100 is proposed to be amended by adding paragraph
(s)(6) as follows:
Sec. 51.100 Definitions.
* * * * *
(s) * * *
(6) For the purposes of determining compliance with California's
aerosol coatings reactivity-based regulation, (as described in the
California Code of Regulations, Title 17, Division 3, Chapter 1,
Subchapter 8.5, Article 3), any organic compound in the volatile
portion of an aerosol coating is counted towards that product's
reactivity-based limit. Therefore, the compounds identified in this
section [i.e., Sec. 51.100 (s)]
as negligibly reactive and excluded
from EPA's definition of VOCs are to be counted towards a product's
reactivity limit for the purposes of determining compliance with
California's aerosol coatings reactivity-based regulation.
* * * * *
[FR Doc. 05-346 Filed 1-6-05; 8:45 am]
BILLING CODE 6560-50-P