[Federal Register Volume 63, Number 148 (Monday, August 3, 1998)]
[Rules and Regulations]
[Pages 41326-41356]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-20147]
[[Page 41325]]
_______________________________________________________________________
Part II
Environmental Protection Agency
_______________________________________________________________________
40 CFR Part 52
Promulgation of Federal Implementation Plan for Arizona; Phoenix PM-10
Moderate Area; Disapproval of State Implementation Plan for Arizona;
Phoenix PM-10 Moderate Area; Final Rule
Federal Register / Vol. 63, No. 148 / Monday, August 3, 1998 / Rules
and Regulations
[[Page 41326]]
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 52
[FRL-6131-6]
RIN 2060-ZA02
Promulgation of Federal Implementation Plan for Arizona--Phoenix
PM-10 Moderate Area; Disapproval of State Implementation Plan for
Arizona--Phoenix PM-10 Moderate Area
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: Under the authority of section 110(c)(1) of the Clean Air Act
(CAA or ``the Act''), EPA is today promulgating a federal
implementation plan (FIP) to address the moderate area PM-10
requirements for the Phoenix PM-10 nonattainment area. Specifically,
for both the annual and 24-hour PM-10 standards, EPA is promulgating a
demonstration that reasonably available control measures (RACM) will be
implemented as soon as possible, a demonstration that it is
impracticable for the area to attain the standards by the statutory
attainment deadline and a demonstration that reasonable further
progress (RFP) is being met.
As part of the FIP, EPA is promulgating a fugitive dust rule to
control PM-10 emissions from vacant lots, unpaved parking lots and
unpaved roads, and is also promulgating an enforceable commitment to
ensure that RACM for agricultural sources will be proposed by September
1999, finalized by April 2000 and implemented by June 2000.
In addition, EPA is today finalizing its disapproval of the Arizona
moderate area plan's RACM, RFP and impracticability, demonstrations
because those demonstrations do not adequately address the Act's
moderate area PM-10 requirements.
EPA recently established a new standard for PM-2.5 and also revised
the PM-10 standards; however, today's action does not address those
standards.
EFFECTIVE DATES: The FIP and SIP actions in this document are effective
on September 2, 1998.
ADDRESSES: A copy of the docket no. A-09-98, containing material
relevant to EPA's proposed and final actions, is available for review
at: EPA Region 9, Air Division, 75 Hawthorne Street, San Francisco,
California 94105. Interested persons may make an appointment with
Eleanor Kaplan (415) 744-1159 to inspect the docket at EPA's San
Francisco office on weekdays between 9 a.m. and 4 p.m.
A copy of the docket no. A-09-98 is also available to review at the
Arizona Department of Environmental Quality, Library, 3033 N. Central
Avenue, Phoenix, Arizona 85012, (602) 207-2217, and at the EPA Air
Docket Section, Waterside Mall, Room M-1500, 401 M Street, S.W.,
Washington, D.C. 20460, (202) 260-7549.
FOR FURTHER INFORMATION CONTACT: For questions and issues regarding the
final measure for agricultural fields and aprons contact John Ungvarsky
(415) 744-1286; for questions and issues regarding the final rule for
unpaved parking lots, unpaved roads and vacant lots contact Karen Irwin
(415) 744-1903; and for other general FIP and SIP questions and issues
contact Doris Lo (415) 744-1287.
SUPPLEMENTARY INFORMATION:
Table of Contents
I. Executive Summary
A. Background
B. Public Involvement in the FIP Process
C. The Final FIP
II. Background
A. SIP/FIP Background
B. Summary of SIP/FIP Proposal
III. Disapproval of Arizona's Moderate Area PM-10 Plan
IV. Final FIP
A. RACM/RACT Demonstration
1. RACT and PM-10 Precursors
2. RACM Demonstration
B. FIP Measures
1. Commitment for Agricultural Sector
2. Rule for Unpaved Parking Lots, Unpaved Roads and Vacant Lots
a. Background
b. Summary of Changes to the Proposed FIP Rule
c. Public Comments and EPA Responses
C. Impracticability Demonstration
1. Annual Standard
2. 24-hour Standard
D. Reasonable Further Progress Demonstrations
1. Revised RFP Demonstration
a. Annual Standard
b. 24-hour Standard
i. Gilbert Monitoring Site
ii. West Chandler Monitoring Site
2. Response to Comments on RFP Demonstrations
E. Indian Reservations
V. Administrative Requirements
A. Executive Order (E.O.) 12866
B. Regulatory Flexibility Act Analysis
1. Regulatory Flexibility Act Requirements
2. RFA Analysis
a. Federal Rule for Unpaved Roads, Unpaved Parking Lots and
Vacant Lots
b. Federal Commitment for Agriculture c. Certification
C. Unfunded Mandates Reform Act (UMRA)
D. Paperwork Reduction Act (PRA)
E. Executive Order 13045: Protection of Children from
Environmental Health Risks and Safety Risks
F. Submission to Congress and the General Accounting Office
G. Petitions for Judicial Review
I. Executive Summary
A. Background
The Phoenix area violates both the annual and 24-hour national air
quality standards for particulate matter with diameters of 10 microns
or less (PM-10). Particulate matter affects the respiratory system and
can cause damage to lung tissue and premature death. The elderly,
children, and people with chronic lung disease, influenza, or asthma
are especially sensitive to high levels of particulate matter. EPA
recently established a new standard for particulate matter with
diameters of 2.5 microns or less and revised the PM-10 standards.
However, EPA also retained the pre-existing PM-10 standards for a
limited amount of time. Today's action only addresses those pre-
existing PM-10 standards.
The primary cause of the PM-10 problem in the Phoenix area is dust
on paved roads kicked up by vehicle traffic, and windblown dust from
construction sites, earth moving operations, unpaved parking lots and
roads, disturbed vacant lots, agricultural fields and aprons, and other
disturbed areas.
When an area violates an air quality standard, the Clean Air Act
(CAA) requires that the area be designated as nonattainment for that
pollutant. Phoenix was originally designated and classified as a
moderate nonattainment area for particulate matter, and Arizona was
required to develop a plan that put into place a basic set of control
measures. These measures did not adequately control the particulate
pollution problem. When the area failed to attain the standards in 1994
it was reclassified as a serious nonattainment area, and the State is
now required to develop a plan with more comprehensive control
measures.
Despite the fact that the State is now working on its serious area
plan, EPA is under court order, as a result of a lawsuit by the Arizona
Center for Law in the Public Interest (ACLPI), to develop a moderate
area federal implementation plan (FIP) for the Maricopa area. EPA is
required to prepare this FIP because the State does not have an
approved moderate area plan. Under the court order, EPA was required to
issue the FIP by July 18, 1998.
In its FIP proposal (63 FR 15920; April 1, 1998), EPA determined
that not all the basic controls on sources contributing to violations
of the particulate standards were in place. While the State had
implemented a
[[Page 41327]]
number of measures, including controls on construction and earth moving
operations, there remained a need for additional emissions reductions.
Having considered its authority and resource constraints, EPA proposed
two measures in that rulemaking for the control of dust from unpaved
roads, parking lots, and vacant lots and agricultural fields and
aprons. Specifically, EPA proposed a fugitive dust rule and an
enforceable commitment in regulatory form to implement control measures
for agricultural PM-10 sources by June 2000. These measures will
contribute to the eventual attainment of both the annual and 24-hour
PM-10 standards. EPA received comments from the public on the FIP
proposal and has made changes to the proposed FIP rule for fugitive
dust sources that it is finalizing today.
The State now intends to submit its serious area particulate plan
in December of 1998. If the plan includes control measures for the
sources covered by the FIP and those measures are approved by EPA, the
Agency will be able to withdraw the final FIP measures. EPA will
continue working with the appropriate State and local agencies, as well
as the agricultural community and the cities in the metropolitan area,
to replace the FIP measures with State measures. EPA believes that
clean air is likely to be achieved faster, and in greater harmony with
local economic and community goals, if its role as a backstop is
minimized by effective State and local actions. Because of the
willingness of the State and local communities to identify and pursue
solutions to their air quality problems, as evidenced by the Governor's
Air Quality Strategies Task Force and the recently adopted Air Quality
Measures Bill (SB 1427), EPA expects successful State and local action.
B. Public Involvement in the FIP Process
On April 16, 1998, EPA held a workshop and public hearing on its
proposal in Phoenix. The workshop provided an opportunity for EPA to
explain to the community why the Agency is imposing this FIP, what
measures are included in the FIP, and who will potentially be impacted
by the FIP. The workshop also provided the community the opportunity to
ask questions of EPA, and to make suggestions with respect to its
proposed action. Following the workshop, EPA took formal testimony at a
public hearing on the FIP proposal. In addition to the hearing
testimony, EPA received 18 comment letters on the proposed FIP.
The comments generally fell into two categories. Environmental and
health organizations supported the dust rule, but commented that the
FIP did not impose enough PM-10 controls for other source categories in
the Phoenix PM-10 nonattainment area. On the other hand, several of the
local jurisdictions and regulatory agencies commented that the FIP-
imposed controls were too stringent. EPA evaluated all the comments,
did additional fieldwork and technical analysis, and revised the FIP
accordingly.
C. The Final FIP
In response to public comments, EPA revised the fugitive dust rule,
but did not change the enforceable commitment for agriculture.
Fugitive Dust Rule
Although EPA has approved a Maricopa County rule (MCESD Rule 310)
which requires controls for unpaved roads, unpaved parking lots and
vacant lots, the County is not adequately enforcing its rule for these
three sources due to lack of resources. Consequently, EPA promulgated a
FIP rule for these sources. EPA's fugitive dust rule is intended to
establish basic levels of control that are substantially equivalent to
those established by Maricopa County Rule 310. The primary difference
between the FIP rule and Rule 310 is the greater specificity and detail
regarding which control measures are appropriate for which sources. For
each source category, the FIP rule includes three to four control
measure options and allows alternative control measures.
In order to effectively implement the FIP rule, EPA is providing
additional inspection resources to the Maricopa County Environmental
Services Department (MCESD) through a CAA section 105 grant. EPA will
rely on these resources to assist the Agency in verifying compliance
with the FIP rule. In order to remove the FIP requirement, MCESD will
have to submit to EPA a credible implementation strategy for Rule 310,
including the provision of its own additional inspection and
enforcement resources that are not provided under an EPA grant. It is
EPA's understanding that MCESD is trying to obtain these additional
resources. EPA will continue working with the County to assist that
effort so that the FIP rule can eventually be rescinded.
Until the FIP is rescinded, however, EPA intends to work
cooperatively with MCESD to inform the regulated community of the FIP
rule's requirements. EPA plans to provide compliance assistance through
informational brochures, toll free numbers and internet access. These
tools will help EPA disseminate as much information as possible to the
public. As new information becomes available, including alternative
control measures that are being developed by regulated parties to
comply with the rule, EPA will collaboratively work with these
regulated parties to provide information to the public.
EPA would like to clarify the Agency's position with respect to a
major issue that was raised by several commenters on the proposed
fugitive dust rule. These commenters believe that the FIP rule requires
a more stringent level of control than Maricopa County Rule 310 and
that, consequently, EPA is imposing an additional economic burden on
local municipalities, and others impacted by the FIP rule. EPA believes
that the FIP rule does not impose any additional compliance burden
beyond that required by Rule 310. Because EPA will fully enforce the
FIP rule, which has not occurred under Rule 310, regulated entities who
have not been in compliance with existing requirements to date will
need to spend the resources necessary to come into compliance. This is
not an additional economic burden, but rather one that some members of
the regulated community have deferred. However, should EPA receive new
information in the future that indicates that the FIP controls are more
stringent than those required by the Clean Air Act, the Agency will
propose appropriate revisions to the FIP.
Enforceable Commitment for Agriculture
As mentioned above, EPA has approved Maricopa County Rule 310 which
requires control of fugitive dust sources, including agricultural
sources. However, MCESD is not ensuring adequate enforcement of the
rule for agricultural fields and aprons. Therefore, EPA is promulgating
an enforceable commitment in regulatory form for the FIP that requires
EPA to propose controls on agricultural sources by September 1999 and
implement these controls by June 2000. The enforceable commitment has
not changed from the April 1, 1998 proposal. In discussions with key
stakeholders, general agreement was reached that these controls will be
in the form of best management practices. EPA believes that this
approach will ensure successful dust control in Maricopa's unique
environment. We have worked closely with the Phoenix
[[Page 41328]]
farming community to develop this commitment, and their comments on the
proposal support it.
In order to remove the FIP requirements, the State will need to
submit and receive approval of a SIP measure that replaces the
enforceable commitment. In fact, the Arizona legislature has passed,
and Governor Hull has signed, the legislative language needed to
establish a state process to develop best management practices for
control of PM-10. EPA expects to receive this legislative language as a
SIP revision very shortly and will act on it expeditiously.
Tribal Issues
There are three Indian reservations located within the Phoenix
nonattainment area. However, since this FIP is designed to fill a gap
that exists in the State plan which does not apply to sources within
Indian country, EPA has not included Indian reservations in this FIP.
All three tribes have expressed an interest in developing air quality
programs. EPA will develop the data, in cooperation with the tribes,
that is needed to properly assess whether controls are required to
attain the standards. EPA will ensure that controls are implemented
either through EPA-approved tribal measures or, if necessary, federal
measures.
Conclusion
EPA appreciates the comments that were made on the proposed FIP and
will continue to work with the community as the Agency moves forward to
implement the FIP measures. EPA will also continue to work with the
community on the development of the State's serious area plan. EPA is
hopeful that the local planning effort will result in an approvable SIP
that will allow EPA to withdraw its FIP.
II. Background
A. SIP/FIP Background
Today's federal implementation plan (FIP) is the result of over six
years of planning and litigation regarding the control of PM-10
emissions in the Phoenix area. On November 15, 1991, as required by the
CAA, the State of Arizona submitted to EPA a moderate area PM-10 state
implementation plan (SIP). EPA found that plan to be incomplete and, as
a result, the State revised and resubmitted it on March 3, 1994. On
April 10, 1995, EPA approved the revised plan which included reasonably
available control measure (RACM) and reasonable further progress (RFP)
demonstrations, and a demonstration that it was impracticable for the
Phoenix area to attain the PM-10 national ambient air quality standards
(NAAQS) by the statutory deadline of December 31, 1994.
On May 1, 1996, the Arizona Center for Law in the Public Interest
(ACLPI) filed in the United States Court of Appeals for the Ninth
Circuit a petition for review of EPA's April 10, 1995 approval of the
State's PM-10 moderate area plan. On May 14, 1996, the Ninth Circuit
vacated EPA's approval of the plan for failing to adequately address
the moderate area PM-10 requirements. Ober v. EPA, 84 F.3d 304 (9th
Cir. 1996). Specifically, the Ninth Circuit found that the State's plan
failed to meet the CAA's requirements for attainment, RFP and RACM for
the 24-hour PM-10 standard and that EPA had failed to provide a
sufficient opportunity for public comment on the RFP and RACM
demonstrations for the annual PM-10 standard.
As a result of the Ninth Circuit's ruling, EPA instructed the State
of Arizona to submit by May 9, 1997 a plan addressing the Act's
moderate area requirements for the 24-hour PM-10 standard at certain
specified monitoring sites and to submit, by December 10, 1997, a full
regional plan addressing those requirements for both the 24-hour and
annual PM-10 standards.1
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\1\ As a result of the litigation and the reclassification of
the Phoenix area as a serious PM-10 nonattainment area, both plans
were also required to address the best available control measure
(BACM), RFP and attainment requirements in the CAA for serious
areas.
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Arizona submitted its 24-hour plan 2 (known as the
microscale plan) on May 9, 1997. On August 4, 1997, EPA approved the
microscale plan in part and disapproved it in part. 62 FR 41856. The
State has not yet submitted the full regional plan, but has indicated
that it intends to do so in December 1998.
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\2\ Plan for Attainment of the 24-Hour PM-10 Standard, Maricopa
County PM-10 Nonattainment Area, Final. ADEQ, May 1997.
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Because EPA was unable to fully approve the State's microscale
plan, the Agency is required by a U.S. District Court order to
promulgate a FIP by July 18, 1998 that addresses the CAA's moderate
area requirements for RACM, RFP and attainment for both the 24-hour and
annual standards. Ober v. Browner, CIV 94-1318 PHX PGR (D.
Ariz.).3
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\3\ The Arizona Center for Law In the Public Interest (ACLPI),
representing the plaintiffs in Ober, in a comment on the FIP
proposal, contends that the proposed FIP does not contain
contingency measures as required by section 172(c)(9) of the CAA.
EPA disagrees. In today's final FIP, EPA is fulfilling an obligation
under the consent decree in the district court Ober case that
specifically requires the Agency to promulgate a federal plan for
Phoenix that meets the moderate area RACM requirement in CAA section
189(a)(1)(C), RFP requirement in section 172(c)(2) or 189(c)(1), and
attainment requirement in section 189(a)(1)(B) of the Clean Air Act.
See paragraph 6 of the Modified Second Consent Decree. EPA's
obligation under the Ober decree does not extend to the section
172(c)(9) contingency measures. The section 172(c)(9) contingency
measure requirement is a separate and distinct statutory requirement
and is not an integral part of RFP or attainment demonstrations
under part D of the CAA. See, e.g., 57 FR 13498, 13543 (April 16,
1992) and 61 FR 51599, 51607 (October 6, 1996). See also footnote 1
in EPA's orginal proposed approval of the State moderate area PM-10
plan for the Phoenix area, 59 FR 38402 (July 28, 1994).
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B. Summary of SIP/FIP Proposal
On April 1, 1998, EPA proposed a FIP for the Phoenix PM-10
nonattainment area that was published in the Federal Register at 63 FR
15920. The proposed FIP included a demonstration that all RACM are
being implemented, a demonstration that it is impracticable to attain
the PM-10 standards with the implementation of all RACM and a
demonstration that RFP in emissions reductions is being made.
As part of its proposed RACM demonstration, EPA proposed a fugitive
dust rule to control PM-10 emissions from vacant lots, unpaved parking
lots and unpaved roads, and an enforceable commitment to ensure that
RACM for agricultural sources will be proposed by September 1999,
finalized by April 2000 and implemented by June 2000. Further detail on
the proposed rule and commitment is provided in connection with the
discussion of EPA's final actions in section IV. below and in the
proposed rulemaking at 63 FR 15920, 15935.
On April 1, 1998, EPA also withdrew a 1996 proposed action to
restore its approval of portions of the State's moderate area SIP for
the annual standard and proposed to disapprove the RACM and
impracticability demonstrations in Arizona's moderate area plan because
those demonstrations do not adequately address the Act's moderate area
PM-10 requirements. Further discussion of the SIP actions is provided
in section III. below and in the proposed rulemaking at 63 FR 15920,
15925.
EPA received 18 public comment letters from a wide range of parties
including private citizens, state and local agencies, industry
representatives, and environmentalists. EPA also held a public hearing
on the proposed FIP in Phoenix at which 7 groups or individuals
testified. Copies of the comment letters and the transcript of the
public hearing can be found in the docket for this rulemaking.
[[Page 41329]]
III. Disapproval of Arizona's Moderate Area PM-10 Plan
In its proposed action for this rulemaking, EPA withdrew its
earlier proposal at 61 FR 54972 (October 23, 1996) to restore the
Agency's approval of Arizona's moderate area PM-10 plan for the Phoenix
nonattainment area.4 At the same time, EPA proposed to
disapprove the RACM demonstration and the demonstration that attainment
by the moderate area attainment deadline was impracticable in the
State's moderate area plan. See 63 FR 15920, 15925-15926. EPA is today
taking final action to disapprove that plan.
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\4\ EPA received one public comment from ACLPI which supported
EPA's withdrawal of its prior proposal to restore the approval of
the State's moderate area SIP as well as the RACM and
impracticability demonstrations therein.
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The CAA establishes specific consequences if EPA finds that a state
has failed to meet certain requirements of the CAA. Of particular
relevance here is CAA section 179(a)(1), the mandatory sanctions
provision. Section 179(a) sets forth four findings that form the basis
for application of a sanction, including disapproval by EPA of a
State's submission based on its failure to meet one or more required
CAA elements. EPA has issued a regulation, codified at 40 CFR 51.31,
interpreting the application of sanctions under section 179 (a) and
(b).
Generally, if EPA has not approved a revised SIP revision
correcting the deficiency, within 18 months of the effective date of
today's rulemaking, pursuant to CAA section 179(a) and 40 CFR 52.31,
the offset sanction identified in CAA section 179(b) will be applied in
the affected area. Similarly, if EPA has still not approved a SIP
revision correcting the deficiency 6 months after the offset sanction
is imposed, then the highway funding sanction will apply in the
affected area, in accordance with 40 CFR 52.31.5 In
addition, CAA section 110(c)(1) provides that EPA must promulgate a FIP
no later than 2 years after a finding under section 179(a) unless EPA
takes final action to approve the revised plan correcting the
deficiency within 2 years of EPA's findings.
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\5\ In a 1994 rulemaking, EPA established the Agency's selection
of the sequence of these two sanctions: the offset sanction under
section 179(b)(2) shall apply at 18 months, followed 6 months later
by the highway sanction under section 179(b)(1) of the Act. EPA does
not choose to deviate from this presumptive sequence in this
instance. For more details on the timing and implementation of the
sanctions, see 59 FR 39859 (August 4, 1994), promulgating 40 CFR
52.31, ``Selection of sequence of mandatory sanctions for findings
made pursuant to section 179 of the Clean Air Act.''
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There are, however, certain exceptions to the general rule for the
application of sanctions described above. The reader is referred to 40
CFR 52.31(d) for the circumstances under which the application of
sanctions may be stayed or deferred.
IV. Final FIP
A. RACM/RACT Demonstration
1. RACT and PM-10 Precursors
In its proposed rulemaking, EPA determined that the SIP already
included reasonably available control technology (RACT) for major
sources of PM-10 and that the FIP did not need to further address this
requirement. See 63 FR 15920, 15927. No comments were received on this
determination.
EPA also proposed to find, based on existing modeling, that major
stationary sources of PM-10 precursors do not contribute significantly
to PM-10 levels in the Maricopa area which exceed the PM-10 air quality
standards, and therefore, RACT on these major sources is not required
under CAA section 189(e). See 63 FR 15920, 15928. Under CAA section
189(e), the control requirements applicable to major stationary sources
of PM-10 must also be applied to major stationary sources of PM-10
precursors, unless EPA determines such sources do not contribute
significantly to PM-10 levels in excess of the standards in the area.
EPA received one comment, addressed below, on this proposed finding.
Comment: ACLPI asserts that EPA's proposal to waive the RACT
requirement for major sources of PM-10 precursors on the ground that
such sources do not significantly contribute to PM-10 levels is flawed
because: (1) it is based on unapproved, draft modeling; (2) it is based
on the unsupported and unwarranted assumption that major source
contributions to secondary particulate levels are proportional to their
presence in the inventory; and (3) it is based on the use of
``significance'' levels from the Act's new source review program, which
are not automatically transferrable to determinations under CAA section
189(e).
Response: EPA used the State's modeling as the technical basis for
this FIP. As such, the modeling was subject to public comment as part
of the FIP proposal and did not require a prior CAA section 110(k)
approval for EPA to use it.
Given the very small presence of major stationary sources in the
precursor inventory (less than 7 percent of the entire precursor
inventory is from major stationary sources), assuming a linear
relationship between major stationary source emissions and their impact
on ambient secondary concentrations is reasonable. EPA estimated that
major stationary sources contribute 0.6 g/m\3\ to exceedances
of the 24-hour standard and 0.3 g/m\3\ to exceedances of the
annual standard, so even if major stationary sources contribute to
secondary particulate formation at 2 to 3 times their presence in the
inventory, they would still be an insignificant source of PM-10 in the
Maricopa area.
The use of significance levels from the new source review program
to determine if a source contributes significantly to PM-10 levels in
excess of the air quality standards in the Phoenix area is discussed in
the next section.
2. RACM Demonstration
In order to determine which RACM to include in the FIP, EPA first
identified a list of 99 potential control measures. See Table 1 in the
proposed rulemaking (63 FR 15920, 15929). This list of measures was
taken from the list of measures developed for the State's 1991 moderate
area plan and included the measures found in EPA's guidance
6 as well as measures recommended by the Maricopa air
agencies and in public comments on the State's moderate area SIP. Nine
additional potential measures were recommended during the public
comment period on FIP: the California Air Resources Board's diesel fuel
standards, a mandatory roadside testing program for diesels, enhanced
diesel inspection and maintenance (I/M), accelerated replacement/
retrofit of pre-1988 heavy duty diesel commercial vehicles, retrofit
existing diesel vehicles (for example, with catalysts), California's
off-road vehicle and engine standards, California's low emission
vehicle standards, continuing expansion of the enforcement of Rule 310,
and a smoking vehicle identification and repair program. See Letter,
ACLPI to EPA, Region 9, May 18, 1998, p. 4 and Public Hearing to
Comment on the Proposed FIP, Reporter's Transcript of Proceedings, p.
7-10 (12:00 p.m. session), p. 5-9 (7:00 p.m. session). EPA added these
nine additional measures to its list of 99, for a total of 108
potential measures.
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\6\ See 57 FR 18070, 18072 (Appendix C) (April 28, 1992).
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Before evaluating the measures as RACM, EPA screened the list to
determine which measures were applicable to the Phoenix area and for
which EPA had legal authority. EPA then screened the list to determine
[[Page 41330]]
which measures it has already approved as State RACM or adopted at the
federal level and considers RACM. Where EPA had already determined a
measure to be RACM, no further analysis of the measure was necessary.
Finally, the Agency evaluated the resulting shorter list of measures
based on EPA's RACM criteria 7 to identify which measures
constituted RACM for the Phoenix area. These three criteria are de
minimis source category, technical feasibility (including when the
measure could be implemented), and cost of implementation. For any RACM
rejected for reasons of technology, cost, size of source category or
timing of implementation, the Agency provided a reasoned justification.
In all, eleven measures addressing fugitive dust from unpaved roads,
unpaved parking lots, disturbed cleared land, and agriculture remained
after the application of the RACM criteria.8
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\7\ See 57 FR 13498, 13540 (April 16, 1992).
\8\ Seven of the additional measures proposed in public comment
are controls for diesel or gasoline on-road tailpipe emissions.
Because diesel and gasoline tailpipe emissions are de minimis source
categories for purposes of PM-10 RACM in Maricopa County, EPA has
determined that the seven measures do not constitute RACM for the
Phoenix area. One measure, California's non-road engine standards,
would control non-road engine emissions. As noted in the RACM
Technical Support Document (TSD) for the proposal (p. 8), EPA
promulgated non-road engine standards in 1995 and considers these
national standards to be RACM. Because RACM has already been adopted
for this category, EPA does not need to further evaluate measures,
such as the California standards, for this category. See 63 FR
15920, 15929. Because the FIP rule controls the same sources as Rule
310, it effectively operates to expand enforcement of the rule.
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A complete description of EPA's approach to determining RACM can be
found in the proposed rulemaking at 63 FR 15920, 15928. The results of
the initial RACM evaluation are presented in Table 3 of the proposed
rulemaking. See 63 FR 15920, 15933. The results of the final RACM
evaluation and a detailed evaluation of each measure including the
reasoned justification if the measure was rejected is in the final RACM
TSD.
EPA received several comments on the RACM demonstration and
responds to the most significant below. EPA has responded to all
comments in the TSD.
Comment: ACLPI comments that the Center disagrees with EPA's
proposal for exempting de minimis source categories from the RACM
requirement of the CAA. ACLPI asserts that there is no authority in the
Act for such an exemption, and that EPA's position that de minimis
source categories need only be controlled to the level necessary to
produce RFP and timely attainment illegally reads the RACM requirement
out of the Act as to such sources.
Response: The CAA does not define ``reasonably available control
measure.'' Because the statute is silent, EPA has the discretion to
develop a reasonable interpretation. Chevron U.S.A. Inc. v. NRDC, 467
U.S. 837, 104 S.Ct. 2778, 81 L.Ed.2d 694 (1984). In 1992 preliminary
guidance (General Preamble), EPA set forth the criteria for states to
apply in determining RACM and reasonably available control technology
(RACT) in PM-10 moderate area SIPs. Among other criteria, if a state
could show that a measure was unreasonable because the emissions from
the affected source would be insignificant, i.e., de minimis, such a
measure could be excluded from further consideration. See 57 FR 13498,
13540. Moreover, EPA believes that determining the reasonableness of a
measure based on the degree to which the regulated source contributes
to the problem is consistent with the RACM/RACT requirements of CAA
sections 189(a)(1)(C) and 172(c)(1). Additionally, RACT is generally
only required for major point sources; i.e., sources above a certain
size threshold. See, for example, section 182(b)(2). See 57 FR 13498,
13541 for discussion of EPA's historical definition of RACT.
In developing its federal plan for the Phoenix area, EPA applied
this criterion by defining a reasonably available measure, in part, as
one that applies to a source that significantly contributes to PM-10
exceedances. See 63 FR 15920, 15927. In discussing the de minimis
criterion in its proposed rulemaking, EPA noted that the regulatory
scheme for particulate matter in subpart 4 of the CAA establishes two
graduated levels of controls, RACM and BACM, depending on the severity
of the area's air quality. See CAA section 189(a) and (b). These
statutory requirements, applicable to moderate and serious PM-10 areas,
respectively, clearly contemplate that sources that contribute to a
lesser degree to the particulate matter problem need not, in the first
instance, bear the burden of emission reductions. Thus, in determining
the initial level of control, EPA believes that it is appropriate to
focus on the reasonable and practicable measures for reducing PM-10
emissions from those sources identified through air quality modeling as
contributing to a greater degree, i.e., significantly, to PM-10
exceedances in the Phoenix area.
Alternatively, even absent EPA's discretionary authority to develop
reasonable interpretations in the face of statutory silence, as stated
in the General Preamble, the inherent authority of administrative
agencies to exempt de minimis situations from a statutory requirement
has been upheld in contexts where an agency is invoking a de minimis
exemption as ``a tool to be used in implementing the legislative design
when ``the burdens of regulation yield a gain of trivial or no value.''
Alabama Power Co. v. Costle, 636 F.2d 323, 360-61 (D.C. Cir. 1979). See
57 FR 13498, 13540. As noted in EPA's response to the comment below,
the provision of RACM for the source categories for which measures were
rejected because of de minimis emissions would have little impact on
the nonattainment problem in the Phoenix area.
Because the Act can reasonably be interpreted to allow the use of a
de minimis criterion for judging whether a measure is RACM, EPA does
not believe that its interpretation that de minimis source categories
need only be controlled to the level necessary to produce RFP and
timely attainment results in reading the RACM requirement out of the
Act as to such sources.
Comment: ACLPI further claims that EPA's de minimis exemption is
contrary to the Act's emphasis on timely attainment and protection of
health, and that control of a source category contributing de minimis
amounts could make the difference between attainment and nonattainment.
Therefore, ACLPI asserts that it is irrational for EPA to assert that
such source categories are invariably de minimis.
Response: For PM-10, EPA has not determined that a given source's
or source category's emissions impact is invariably de minimis for
determining RACM. What constitutes a de minimis source category is
dependent upon specific facts of the nonattainment problem under
consideration. In particular, it depends upon whether requiring the
application of RACM for such sources or source categories would
contribute significantly to the Act's purpose of achieving attainment
of the NAAQS as expeditiously as practicable.
For the Phoenix PM-10 nonattainment problem, the subject of this
FIP, controls on the source categories that EPA found to be de minimis
would not make the difference between attainment and nonattainment.
Five Phoenix area monitoring sites with expected PM-10 exceedances were
evaluated to determine which source categories were de minimis for the
purpose of the RACM demonstration in this FIP: four sites for the 24-
hour standard and one site for the annual standard. In order to be
considered a de minimis source category in the FIP's RACM analysis, a
source category had to be de minimis at all five monitoring
[[Page 41331]]
sites and de minimis for both the 24-hour and annual standards. As
illustrated in Table 1, three of the five evaluated monitoring sites
did not have de minimis sources identified as contributing anything to
the exceedance. At the two remaining sites--Greenwood and Salt River--
de minimis source categories contribute substantially less than 10
percent to the exceedance and in neither case would complete
elimination of these sources result in attainment at the
site.9 Hence in Phoenix, the use of a de minimis source
category criterion to judge the reasonableness of controls has not
excused controls on sources that would make the difference between
attainment and nonattainment.
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\9\ EPA has already approved the attainment demonstration for
the Salt River monitor. See 62 FR 41856, 41862 (August 4, 1997).
This attainment demonstration showed that controls on the de minimis
source categories would not result in more expeditious attainment.
Table 1.--Contribution of De Minimis Sources to Exceedances in the
Phoenix Metropolitan Area
------------------------------------------------------------------------
De
De Minimis Minimis
sources sources
without without
Monitor RACM as RACM as
percent of percent
exceedance of PM-10
standard
------------------------------------------------------------------------
24-Hour Exceedances:
West Chandler................................... 0 0
Gilbert......................................... 0 0
Maryvale........................................ 0 0
Salt River...................................... 3.9 4.3
Annual Exceedances:
Greenwood....................................... 4.7 5.6
------------------------------------------------------------------------
Comment: ACLPI claims that EPA's choice of 5 g/m\3\ and 1
g/m\3\ as the significance thresholds for contributors to 24-
hour and annual PM-10 levels respectively has no rational basis
whatsoever and that the fact that EPA uses these thresholds in the new
source review programs does not make them logical choices as thresholds
for an entirely different purpose.
Response: As stated in the proposal, EPA is relying on the new
source review permitting program's significance thresholds ``as a
surrogate for determining which source categories require application
of RACM'', and ``not for determining which source categories need
controls for attainment.'' 63 FR 15920, 15927. The new source review
program and nonattainment planning provisions are both elements in the
CAA's title I provisions to attain and maintain the health-based air
quality standards. The new source review program's significance levels
are used to judge when a source will have a significant impact on a PM-
10 nonattainment area. See 40 CFR 51.165(b). For the purposes of this
FIP only, EPA used the 5 g/m\3\ and 1 g/m\3\
significance thresholds for essentially the same purpose: to judge
whether a source or source category has a significant impact on the
Phoenix PM-10 nonattainment area.
A significance threshold should be set at a level that segregates
the insignificant source categories from the ones that contribute most
to a nonattainment problem. As noted above in Table 1, in Phoenix, de
minimis sources, i.e., those that contribute less than 5 g/
m\3\ to the 24-hour standard exceedances and 1 g/m\3\ to the
annual standard exceedances, account in total for less than 10 percent
of the impact at any monitor that exceeds either PM-10 standard. Thus,
because the selected thresholds result in the imposition of controls on
the sources that have a greater emissions impact on the air quality
problem, their application, in EPA's view, is most likely to result in
substantial air quality improvements.
There were 12 source categories that fell beneath these surrogate
significance thresholds and which EPA determined, therefore, were de
minimis in the proposed FIP's RACM analysis: industrial yards, surface
mining, other industrial activities, gasoline-powered engines, on-road
motor vehicles, diesel-powered on-road motor vehicles, residential wood
combustion, other fuel combustion (e.g., residential space and water
heaters and commercial boilers), open burning and other area sources,
charbroiling, locomotives, airport ground support equipment, and major
point sources. Measures for residential wood combustion, open burning,
and major point sources categories were excluded from the RACM analysis
because RACM had already been approved for them. The list of potential
RACM did not include measures for the other fuel combustion sources or
the charbroiling categories, nor were any measures for these categories
suggested in the public comments received on the FIP. See Table 1 in
the proposed rulemaking, 63 FR 15920, 14929. The industrial yards,
surface mining, and other industrial activities source categories were
found to have an impact only at the Salt River monitor, a monitor for
which EPA has already approved an attainment demonstration that showed
controls on these sources would not result in more expeditious
attainment. See 62 FR 41856, 41862.
Tailpipe emissions from gasoline-powered engines which account for
only 0.3 g/m \3\ impact on the annual standard exceedance at
the Greenwood monitor are already subject to stringent controls
including the emission standards under the Federal Motor Vehicle
Control Program, Arizona's premier I/M program, and the State's Clean
Burning Gasoline program. Diesel powered on-road vehicles including
trucks are also subject to national diesel fuels standards and tailpipe
emission standards. See 40 CFR 80.29 (diesel fuel standards) and 40 CFR
part 86, subpart H and 62 FR 54694 (October 21, 1997) (diesel tailpipe
standards).
Finally, it is important to review how the significance thresholds
actually affected the outcome of the RACM analysis. EPA used the de
minimis criterion as a justification for excluding measures for
tailpipe emissions from on-road motor vehicles, locomotives, airplanes,
airport ground equipment, off-road motorcycles, and heavy-duty
construction equipment. See Table 3 in the proposed rulemaking, 63 FR
15920, 14933. The two latter categories are very small contributors to
the overall non-road engine source category. In total, these categories
contributed 1.4 g/m \3\ to the annual standard exceedance at
the Greenwood monitor and nothing to the 24-hour exceedances.
Comment: The Arizona Department of Environmental Quality (ADEQ)
comments that the determination of significant and de minimis sources
for the annual PM-10 standard which was based upon preliminary modeling
results using Urban Airshed Modeling (UAM) should be re-evaluated
because the emissions inventory and dispersion modeling have not been
reconciled against receptor modeling, as recommended under EPA's
guidance for PM-10 plans (PM-10 SIP Development Guideline, EPA-450/2-
86-001, June 1986). ADEQ suggests that this should concern EPA because
the inventory source apportionment differs greatly from receptor
modeling source apportionment from the 1989-90 Phoenix PM-10 Study
(Desert Research Institute, 1991). ADEQ states that, while these data
are not relatively recent, large changes in the character of ambient
particulate pollution since the time that study was conducted would not
be expected and these data have been corroborated by more recent
chemical analysis of particulate monitor filters from monitors in the
urbanized portion of the Phoenix metropolitan area. ADEQ notes that the
emission inventory is dominated by sources of geologic PM, even for the
fine (PM-2.5 and smaller) particulate. ADEQ states that it rarely
[[Page 41332]]
finds more than 10 percent geologic materials in the measured fine PM
fraction, whereas the emissions inventory estimates that over 70
percent of the fine PM is geologic. Based on the filter data, ADEQ
concludes that the role of combustion sources relative to geologic
sources is underestimated in the inventory, stating that carbon
particles, both primary and secondary, rival geologic material in terms
of PM-10 mass, but are minor in the PM-10 inventory that EPA is using.
Response: EPA agrees that, ideally, dispersion and receptor
modeling should be reconciled, using accepted protocols, such as the
one in Protocol for Reconciling Difference Among Receptor and
Dispersion Models (EPA-450/4-87-008). However, the concentrations to be
reconciled should be matched in terms of sampling period; i.e., 1989/90
data should not be used to reconcile modeling for 1995. Moreover,
modeling of recent high PM-10 days would not necessarily be expected to
match those observed in the Desert Research field study. During that
field study, daily concentrations averaged 4 to 97 g/m \3\,
depending on the monitoring site, with no 24-hour NAAQS exceedances
observed. Although the data from this field study were all that were
available for the State's initial moderate area plan and were
acceptable on that basis, it is not reasonable to require analysis of
recent, exceedance days to match the earlier work. Unfortunately, no
later receptor modeling was available for the FIP for reconciliation.
See also the response to ACLPI's comment regarding the differences
between the 1989 and 1995 emission inventory in section IV.D.2. below.
B. FIP Measures
1. Commitment for Agricultural Sector
In its April 1, 1998 proposed rulemaking, EPA proposed an
enforceable commitment to adopt and implement RACM as required by CAA
section 189(a)(1)(C) for the agricultural sector in the Phoenix
nonattainment area. Specifically, the proposed commitment contained
enforceable milestones for EPA's proposal (by September 1999), final
adoption (by April 2000), and implementation (by June 2000) of RACM for
agricultural fields and aprons. In the proposal, EPA explained its
intention to use a stakeholder approach for the development of best
management practices (BMPs) to meet the CAA's RACM requirement and
provide PM-10 emission reductions from agricultural sources in the
Phoenix area.
EPA is today taking final action to promulgate an enforceable
commitment in 40 CFR 52.127 to adopt and implement RACM as required by
CAA section 189(a)(1)(C) for the agricultural sector. While EPA
received a number of comments on its proposed commitment, to which it
responds below and in the TSD, the Agency is, in this final rule,
retaining the text of the commitment as proposed.
Comment: ACLPI and the American Lung Association of Arizona (ALAA)
claim that a mere commitment to develop unspecified controls for
agricultural fields and aprons is inadequate and does not meet the CAA
requirements or EPA guidance for enforceable measures as expeditiously
as practicable. The commenters contend that such a commitment offers no
assurance that adequate controls will ever be adopted.
Response: Because the commenters provide no citations or analysis,
in favor of a broad claim of inadequacy, EPA is left to divine the
precise nature of their legal challenge to the provisions for
agriculture in the proposed FIP. To the extent that the commenters are
suggesting that ``a mere commitment'' is not cognizable under the CAA,
EPA notes that the Agency has a long history of approving enforceable
commitments in SIPs under the statute. Moreover, the milestones in such
commitments have routinely been deemed to be enforceable in CAA section
304 citizen suits. For an extensive discussion of the legal basis for
such approvals under the CAA as amended in 1990, see 62 FR 1150, 1155-
1157 (January 8, 1997).
In its April 1, 1998 Federal Register notice, EPA proposed a
commitment to adopt and implement RACM for agricultural fields and
aprons by specified dates that, as finalized today, will be enforceable
in a citizen suit. In that proposal, EPA explained its rationale for
addressing agricultural sources of PM-10 emissions. In short, the
Agency believes that, given the current state of its knowledge of the
local agricultural community and conditions, the BMP process the Agency
intends to pursue is the approach most likely to lead to effective
controls on these sources in the shortest possible time frame. See 63
FR 15920, 15935-15936.
EPA has issued detailed preliminary guidance on the appropriate
methodology for determining RACM under CAA sections 172(c)(1) and
189(a)(1)(C), as well as a list of available fugitive dust control
measures. See 57 FR 13540-13541; 13560-13561 and 57 FR 18071, 18072.
EPA followed this guidance in determining federal RACM in the proposed
FIP. In carrying out its FIP commitment to propose RACM for
agricultural fields and aprons by no later than September 1999, EPA
will adhere to the RACM guidance in effect for these sources at that
time. As with all proposed EPA rulemakings, the public will have the
opportunity to state its views on the legal adequacy of the proposed
controls. Should EPA fail to propose RACM for these sources by
September 1999, ACLPI and ALAA may pursue their remedies under CAA
section 304. Once EPA takes final adoption action, they can of course
petition for review of that action under CAA section 307.
Comment: ACLPI argues that since agricultural control measures have
been adopted in other states, e.g., in California's Coachella Valley,
or identified by the Governor's 1996 Task Force, there is no excuse for
delay. ACLPI also comments that even if further delay in development of
agricultural controls were warranted, EPA cannot justify taking more
than a year to develop proposed rules and that there is no reason the
Agency cannot adopt enforceable rules within 6 months. ACLPI asserts
that 6 months would allow time for obtaining stakeholder input without
turning rule development into a protracted exercise.
Response: Prior to the FIP proposal, EPA evaluated available
measures for agriculture adopted by the South Coast Air Quality
Management District (SCAQMD): 403--Fugitive Dust; 403.1--Wind
Entrainment of Fugitive Dust; and 1186--PM-10 Emissions from Paved and
Unpaved Roads, and Livestock Operations. As discussed in the FIP
proposal, EPA determined that there was insufficient information
available to conclude that implementing the controls in these rules in
Maricopa County would, taking all relevant factors into account, be
appropriate, i.e., reasonable, and thus constitute RACM for this area.
See 63 FR 15920, 15935. EPA intends to consider whether these or other
measures would be appropriate for the Phoenix area during the BMP
development process.
ACLPI dismisses EPA's statements regarding the Agency's inability
to ascertain the suitability of the SCAQMD measures for the Phoenix
area by asserting that the ``techniques for controlling agricultural
emissions are well known.'' This assertion ignores the fact, noted by
EPA in its proposed rulemaking, that PM-10 strategies in an
agricultural context are uniquely based on local circumstances, and
could vary greatly due to factors such as regional climate, soil type,
growing season, crop types, water availability, and relation to
[[Page 41333]]
urban centers. 62 FR 15920, 15935. A resolution of these uncertainties,
in the context of an assessment of the potential mix of control
measures, is critical to a determination of whether controls such as
those contained in the SCAQMD rules are reasonably available for the
Maricopa County nonattainment area and will contribute to attaining the
PM-10 standards in the area. Such an assessment is fully consistent
with EPA's guidance regarding the process for determining RACM.
As a result, EPA determined that the goal of attaining the PM-10
standards in Maricopa County with respect to agricultural sources would
be best served by engaging all interested stakeholders in a joint
comprehensive process on the appropriate mix of agricultural controls
to implement in Maricopa County. EPA believes that this process,
despite the additional time needed to work through it, will ultimately
result in a best and most cost-effective controls on agricultural
sources in the County. EPA has thus committed in the final FIP to
propose RACM for the agricultural sector by September 1999, with final
adoption in April 2000. Given the number of potential BMPs, the variety
of crops types, the need for stakeholder input, and the time necessary
to develop the BMPs into effective control measures, EPA believes that
the adoption schedule is expeditious.10
---------------------------------------------------------------------------
\10\ It is important to note that the measures identified by the
Governor's 1996 Task Force were initially intended to be voluntary
and would require a process virtually identical to that envisioned
by EPA in its FIP in order to be developed into effective controls.
The Task Force measures, along with any other measures potentially
available for Maricopa County, will be evaluated as part of the BMP
development process.
---------------------------------------------------------------------------
Comment: The American Farm Bureau Federation (AFBF) contends that
because little data exist for agriculture's contribution to PM-10,
there is a need for sound science before regulation and the California
Regional Particulate Matter Air Quality Study (CRPMAQS) will provide
additional data. AFBF claims that any agricultural emission controls
are premature and should be postponed until the CRPMAQS data is
available. The Maricopa County Farm Bureau (MCFB) also comments that
agricultural controls are premature, citing University of California
and University of Arizona research suggesting current PM-10 emission
estimates from agricultural sources are overstated.
Response: On August 4, 1997, EPA disapproved portions of the
State's microscale plan, in part because it demonstrated, through a
scientific study, that agricultural sources contribute significantly to
exceedances of the PM-10 air quality standards in Maricopa County, but
did not provide for the implementation of RACM for agricultural fields
and aprons. 62 FR 41856, 41862. As a result, EPA is providing for RACM
implementation for these sources.
Moreover, other than vague statements about lack of data and sound
science, AFBF failed to describe any specific deficiencies in the
scientific study that resulted in the conclusions in the microscale
plan. Likewise, MCFB failed to cite any specific research data that
would refute those conclusions. EPA believes that the microscale plan's
conclusions were based on sound science, as demonstrated by an
intensive study throughout 1995 which included field surveys, aerial
photography, examination of activity logs, and interviews with source
operators. See Microscale plan, Appendix A, Chapter 4. The study
resulted in substantially better emissions inventory data than were
usually available. The study included extensive monitoring and a
thorough analysis of the area's PM-10 problem. The State used locally-
developed emission factors in its modeling. Overall, the episodes
modeled in the microscale plan are representative of the conditions
under which the exceedances of the 24-hour PM-10 NAAQS occur. Model
performance was generally good and well within what can be expected
from the type of model used. See 62 FR 31025, 31031.
EPA will use the CRPMAQS and any other information appropriate for
the Maricopa area as the data become available. However, it is
important to note that the PM-10 exceedances in Maricopa County are
typically caused by wind-blown, primary particulates (i.e., geologic
sources). The PM-10 exceedances in the San Joaquin Valley (where the
CRPMAQS is underway) are caused by primary and secondary particulates
and typically are not associated with high wind events. While the
CRPMAQS will yield a tremendous amount of new information, much of the
information may not be applicable to Maricopa. For the foregoing
reasons, EPA does not believe that postponing development of the BMPs
pending the completion of the CRPMAQS would be appropriate.
Comment: AFBF comments that this past March, the U.S. Department of
Agriculture-Natural Resources Conservation Service (USDA-NRCS)
Agricultural Air Quality Task Force agreed to develop a PM-10
implementation policy that will help guide states and EPA when dealing
with agriculture and PM-10. Thus, AFBF believes that any agricultural
emission controls are premature and should be postponed until a USDA
Task Force policy is available. MCFB and AFBF believe that if USDA
develops a national policy which outlines voluntary controls for
agricultural PM-10, enforceable provisions should be removed from the
FIP and SIP. They state that the final FIP should include language that
will allow for the FIP to be revised as data and policy become
available.
Response: Regarding the issue of whether the FIP agricultural
provisions are premature, see EPA's response to AFBF's previous
comment. In addition, EPA does not believe that postponing development
of the BMPs pending the development of a USDA Task Force policy would
be appropriate. EPA has worked extensively with MCFB, the Arizona Farm
Bureau Federation and other stakeholders to craft a workable strategy
for Maricopa County. The Arizona Federation supported legislation
recently signed by Arizona Governor Hull for a State-led process for
developing BMPs.11 EPA supports the position of the farming
interests in Maricopa County to implement the recently adopted
legislation and thereby maintain local control over the solution.
---------------------------------------------------------------------------
\11\ Governor Hull recently signed SB 1427 ``Air Quality
Measures'' which authorizes a state-led BMP process. Section 16.
Title 49, chapter 3, article 2, of the Arizona Revised Statutes was
amended by adding section 49-457, Agricultural best management
practices committee; members; powers; permits; definitions. The
State has indicated to EPA that section 49-457 will be submitted to
EPA in the coming months as a replacement for the portion of the FIP
which addresses agricultural sources.
---------------------------------------------------------------------------
If EPA adopts a national policy for PM-10 emissions from
agricultural sources that the State and the Maricopa County farming
community would like to use, EPA will assess its implications for the
area and work with the agricultural leaders and the local air agencies
on any appropriate changes to the current strategy.
Comment: MCFB comments that the 24-hour exceedances attributed to
agricultural sources occurred during a dust storm and unless BACM are
in place, EPA will not consider natural occurrences, such as a dust
storm, as a source of PM-10. Because dust storms will happen whether or
not BACM are in place, MCFB would like this policy to be changed before
any industry is burdened with control measures.
Response: Contrary to MCFB's contention, the exceedances which
implicate agricultural sources did not occur during dust storms. Rather
they
[[Page 41334]]
resulted from normal wind conditions which routinely occur. A review of
the exceedances and monitoring data used in support of the State's
microscale plan indicates that the exceedances were localized and did
not occur at many of the monitoring sites. If the exceedances had been
caused by a dust storm, exceedances would be expected throughout the
County.
EPA does have a policy 12 that permits dust raised by
high winds from anthropogenic sources controlled with BACM to be
treated as due to a natural event. Key aspects of the policy include
that EPA will not designate an area as nonattainment when NAAQS
violations are caused by natural events and EPA would consider
redesignating an area to attainment if it had BACM in place and the
only violations were due to high wind events. However, and more
importantly, the policy is explicit that all exceedances, no matter
what the cause, are of concern to public health and steps need to be
taken to reduce public exposure to unhealthful particulate levels.
Therefore, there is a need to reduce the level of exceedances during
natural events even if the exceedances cannot be eliminated; hence, the
requirement for BACM.
---------------------------------------------------------------------------
\12\ Memorandum from Mary D. Nichols, EPA, to EPA Regional
Offices, entitled ``Areas Affected by PM-10 Natural Events,'' dated
May 30, 1996.
---------------------------------------------------------------------------
Comment: MCFB states that Maricopa County is the fastest growing
county in the nation and that rapid growth is forcing land out of
agriculture at a rate of 6,000 acres per year. MCFB urges that because
the growth is pushing agriculture out of business, agriculture should
be released from further controls or it will only speed the
disappearance of agriculture from the Phoenix area. MCFB believes that
the only way to eliminate PM-10 is to regulate farmers out of existence
in Maricopa County.
Response: In the FIP proposal, EPA acknowledged that agricultural
land is being converted into other uses. However, even with rapid
conversion, agricultural lands will remain a significant source of PM-
10 for the foreseeable future. EPA's purpose here is to effectively
control PM-10, not to put farmers out of business. Through the
stakeholder process, EPA will work with the farming community to meet
that goal while ensuring that the BMPs developed to meet the CAA's RACM
requirement are economically feasible. In addition, some cities in
Maricopa County have begun to express interest in preserving
agricultural lands for open space. This interest may reduce the amount
of land being converted from agricultural use.
2. Rule for Unpaved Parking Lots, Unpaved Roads and Vacant Lots
a. Background. In its April 1, 1998 notice, EPA proposed a FIP rule
for Phoenix that required RACM for unpaved parking lots, unpaved roads
and vacant lots. The reader should consult that notice for a detailed
discussion of the requirements EPA proposed for these sources. See 63
FR 15920, 15937.
In the FIP proposal, EPA explained that MCESD has adopted, and EPA
has approved, MCESD Rule 310 that requires RACM for fugitive dust
sources, including those regulated in the FIP. However, because EPA had
previously determined that the County was not enforcing the rule for
these three PM-10 sources, the Agency disapproved the State's RACM
demonstration for them. 62 FR 41856, 41862.13 As a result,
EPA is promulgating a federal RACM rule covering these sources. Because
the deficiency in the State's RACM demonstration did not relate to the
substance of MCESD's fugitive dust rule, EPA modeled its proposed rule
on Rule 310.
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\13\ Section 221 of Rule 310 is entitled ``Reasonable Available
Control Measure (RACM)'' and the term ``RACM'' is used throughout
the rule. EPA has approved Rule 310 into the SIP as meeting the
enforceability requirements of CAA sections 110(a)(2)(A) and
172(c)(6). See 62 FR 31025, 31032 (June 6, 1997) and 62 FR 41856,
41864. Regardless of the terminology in Rule 310, as just noted, EPA
has determined that the County's implementation of the rule does not
meet the RACM implementation requirement of CAA section 189(a)(1)(B)
for unpaved roads, unpaved parking lots and vacant lots.
---------------------------------------------------------------------------
The primary difference between the County rule and EPA's proposed
rule was that, because EPA's San Francisco office would be responsible
for its enforcement, the FIP rule provided greater specificity and
detail regarding which control measures are appropriate for which
sources. See 63 FR 15920, 15937; 15942-115943. Since, by its terms, the
requirements of Rule 310 are so broad, the general effect of this
greater specificity and detail was that EPA's proposed FIP rule, in its
entirety, while achieving what the Agency believed to be a RACM level
of control, was somewhat narrower in scope than the County's rule as it
relates to unpaved roads, unpaved parking lots and vacant
lots.14
---------------------------------------------------------------------------
\14\ For example, section 312 of Rule 310 regulates users of
unpaved roads, while EPA's rule proposed regulation of only owners
and operators; and Rule 310 does not exempt any unpaved roads, while
EPA's rule included a low ADT exemption.
---------------------------------------------------------------------------
EPA is today promulgating a final FIP fugitive dust rule at 40 CFR
52.128 that incorporates a number of changes in response to public
comments. Those changes, summarized and discussed below and in the TSD,
reflect the same fundamental philosophy described above. The net result
of the substantive changes is to provide sources with greater
flexibility than provided in the FIP proposal.15 For
example, the final FIP rule includes an increase from 0.10 acre to 0.50
acre in the de minimis disturbed surface area level for vacant lots; an
increase from 150 average daily trips (ADT) to 250 ADT in the ADT
exemption level for unpaved roads; a new de minimis use level for
unpaved parking lots; and the elimination of the dust control plan
(DCP) requirement for weed abatement.
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\15\ For the reasons discussed in this section, EPA believes
that the final FIP rule, with the modifications made in response to
comments, meets the RACM requirements of the CAA.
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In a separate rulemaking, EPA plans to propose and take comment on
amendments to some of the alternative control measure (ACM) and test
method provisions of today's final rule. While EPA believes that these
changes are warranted,16 EPA cannot include them in today's
final action because they are beyond the scope of the proposed FIP
rule. Because EPA has a court-ordered deadline of July 18, 1998 to
promulgate the FIP rule, the Agency is taking final action on its rule
without the ACM and test method changes, but will publish the proposed
amendments shortly.
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\16\ EPA intends to propose new test methods to replace the
opacity (and corresponding opacity standard) and the visible crust
method as proposed in the FIP and include an additional test method
for standing vegetation. In response to public comments, EPA
conducted technical field work in Phoenix on the proposed test
methods. While they were the best available methods known to EPA at
the time of proposal, additional analysis has indicated that other
test methods may be more accurate and comprehensive. EPA also
intends to propose the elimination of the requirement to submit ACMs
to EPA for approval unless the ACM's effectiveness cannot be
measured by the test methods or specific language included in the
rule. EPA is also considering whether to propose an amendment to the
FIP rule that would require RACM for unpaved roads that are neither
owned nor maintained by a public entity.
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b. Summary of Changes to the Proposed FIP Rule. In addition to the
substantive changes to the proposed FIP rule referenced above that
provide additional flexibility, the final FIP rule also includes
changes that clarify or revise the RACM implementation schedules. Other
final FIP rule changes provide minor clarifications of the FIP rule
provisions such as adding language to clarify test methods, exemptions
and definitions. The substantive changes to the final FIP rule are
summarized below by source category.
Unpaved Parking Lots and Unpaved Roads. The final rule:
[[Page 41335]]
Increases the ADT exemption level for unpaved roads from
150 ADT to 250 ADT.
Includes a de minimis use exemption for unpaved parking
lots and requires RACM only on surfaces where vehicles park.
Eliminates the 2-inch requirement for gravel and relies on
the applicable test methods for compliance.
Includes organic stabilizers in addition to chemical
stabilizers.
Eliminates the provision requiring RACM only where 70
percent of the unpaved road is located within the Phoenix nonattainment
area and focuses on the unpaved roads or portion of an unpaved road
located within the nonattainment area.
Clarifies that operators of privately-owned public access
unpaved roads are the parties responsible for compliance with the RACM
requirements.
Vacant Lots. The final rule:
Eliminates the requirement for dust control plans in favor
of a provision requiring compliance with three RACM options.
Increases the de minimis disturbed area level from 0.10
acre (proposed rule) to 0.50 acre.
Includes a de minimis exemption (5,000 square feet) for
lots disturbed by motor vehicle trespassing.
Modifies the time frame for RACM to be implemented on
disturbed surfaces from eight months to 60 days, except for the initial
eight months following the effective date of the rule.
Expands RACM for motor vehicle disturbances on vacant
lots.
Eliminates the 2-inch requirement for gravel and relies on
the applicable test methods for compliance.
Includes an initial eight-month time frame following the
final rule's effective date for implementation of RACM for motor
vehicle disturbances and weed abatement.
Clarifies the rule's test methods and contains language
for some test methods that were previously only referenced in the
proposed rule.
General Changes. The final rule:
Clarifies the requirements to which exemptions apply.
Clarifies that the tribal lands within the Phoenix PM-10
nonattainment area are not covered by the provisions of the FIP rule.
Clarifies that Apache Junction is not covered by the
provisions of the FIP rule.17
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\17\ The Maricopa PM-10 nonattainment area is comprised of the
greater Phoenix metropolitan area in Maricopa County and the Apache
Junction area in Pinal County. The State submitted separate moderate
area PM-10 plans for the Maricopa County portion and the Pinal
County portion of the nonattainment area. The incompleteness finding
that triggered EPA's obligation to promulgate this FIP was made only
on the submitted plan for Maricopa County and thus EPA's FIP
authority only extends to this part of the nonattainment area. The
Pinal County plan became complete by operation of law on May 14,
1992. As a result, EPA is clarifying that this FIP does not cover
the Apache Junction area.
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c. Public Comments and EPA Responses. Implementation Costs.
Comment: The Maricopa Department of Transportation (MCDOT) and the
Arizona Chamber of Commerce (ACOC) assert that EPA's interpretation of
Maricopa County Rule 310 as currently requiring suppression of dust on
all unpaved public access roads is incorrect. MCDOT claims that in the
development of the rule, MCDOT, MCESD and other stakeholders agreed to
commit to a dust reduction program. MCDOT states that the rule called
for use of RACM on unpaved roads in Section 312 with reference to the
list of measures in Section 221. MCDOT further states that, while not
explicitly stated in the rule, EPA and MCESD have always interpreted
RACM to include a financial and cost effectiveness test and that MCESD
has in practice accepted the SIP commitments for dust suppression and
the five-year work plan for capital projects as what was reasonably
available. MCDOT says that its commitment was to stabilize 25 miles of
roadway per year. MCESD also makes similar comments regarding its
acceptance of the five-year work plans for capital projects as
satisfying the RACM requirement.
Response: EPA notes that MCDOT concedes, by its references to
sections 312 and 221 of Rule 310, that the regulatory scope of these
sections of Rule 310 encompasses the same universe of sources and
measures as the proposed FIP rule. Thus, the issue is whether any
acceptance by MCESD of MCDOT's SIP commitment to stabilize 25 miles of
roadway per year constitutes compliance with the rule. In EPA's final
action on the State's microscale plan, EPA determined that the MCESD's
implementation of Rule 310 (i.e., enforcement on a complaint basis for
vacant lots, unpaved parking lots and unpaved roads 18) is
inadequate and consequently disapproved the RACM demonstration in that
plan for these sources. 62 FR 41856, 41865. EPA received no public
comments which disagreed with this finding. Moreover, MCESD has never
incorporated a 25 mile stabilization limit into Rule 310. Nor has EPA
made a determination or approved into the Phoenix PM-10 SIP MCDOT's 25
mile stabilization commitment as representing a RACM level of control.
Therefore, as a legal matter, such an understanding between MCESD and
MCDOT does not establish MCDOT's commitment as meeting the RACM
requirements of the CAA.19
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\18\ The fact that MCESD enforces Rule 310 for these sources on
a complaint basis is clear evidence that they are included within
the regulatory scope of the rule.
\19\ See footnote 13.
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As stated above, EPA modeled its FIP rule on Rule 310, but provided
greater detail and specificity which had the effect of narrowing the
scope of Rule 310. As explained in more detail below, EPA believes,
based on the information currently available to the Agency, that the
requirements of the final FIP rule meet the economic feasibility
criterion in the Agency's guidance and represent RACM for unpaved
roads.
Comment: MCDOT and the City of Mesa claim that EPA did not provide
any analysis as to what methods or criteria were used to identify RACM
and that there is no cost-benefit analysis provided to demonstrate the
reasonable availability and effectiveness of the proposed measures. The
City of Mesa asserts that, as EPA stated in the proposed rulemaking,
any measures that are determined to be de minimis, technologically
infeasible or unreasonably costly should be removed from the list of
RACM. This commenter concludes that EPA did not conduct this analysis
as part of the proposed FIP.
Response: In section IV.B. of its proposed rulemaking, EPA set
forth the criteria that the Agency must apply in determining what
measures constitute RACM. In general, EPA excludes measures it
determines to be unreasonably costly, technologically infeasible or
that apply to sources of PM-10 that are de minimis. 63 FR 15920, 15926.
In section V of the FIP proposal, EPA provided a detailed description
of its approach for determining which RACM to include in the proposed
FIP. 63 FR 15920, 15927-34. For the purposes of the RACM analysis,
public sector sources, like EPA, should evaluate the criterion relating
to the cost of control measure implementation by considering the
reasonableness of potential RACM based on the financial and resource
capabilities of the governmental entity responsible for implementing
such measures. The FIP RACM analysis involved a list of 99 potential
RACM which were evaluated against 2 sets of criteria: (1) to determine
if a measure was appropriate for federal implementation; and (2) to
determine if a measure was RACM. The latter set of criteria include
economic feasibility.
[[Page 41336]]
EPA did not provide a cost-benefit analysis for the proposed FIP
measures because, as discussed in the proposed FIP's Regulatory
Flexibility Analysis, all of the requirements of the FIP's fugitive
dust rule are already required under the County's Rule 310. See 63 FR
15920, 15942. In fact, EPA believes, as stated previously, that the
scope of the FIP rule as proposed (and as modified in this final
action) is narrower than that of Rule 310. Hence the costs of
compliance with the FIP rule should, to the extent that there is any
cost differential, be less than those for Rule 310.20 See 63
FR 15920, 15943-15944 and section VII.B.2. below for detailed
discussions of this issue.
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\20\ For this reason, EPA disagrees with MCDOT's claim that
compliance with the FIP rule implicates the cost-benefit analysis
requirements of the Unfunded Mandates Reform Act. Nor does the FIP
rule constitute a major federal action under the National
Environmental Policy Act (NEPA) as the commenter suggests. EPA
actions under the CAA are expressly exempt from that statute. 15
U.S.C. Sec. 793(c)(1).
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Nevertheless, EPA did include estimates of control effectiveness
and unit costs in the TSD for the FIP rule.21 As discussed
in the TSD, the control effectiveness estimates were based on available
data, which was limited. Thus only relatively crude estimates were
developed for the emissions reductions associated with the FIP rule (or
implementation of Rule 310). The unit costs are based on information
found in documents prepared by or referenced by the Maricopa
Association of Governments. The costs associated with the FIP rule and
their relationship to the RACM determination are discussed further in
response to the following comment.
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\21\ See sections 5.0, ``Emissions Reductions,'' and 6.0, ``Cost
Estimates'' of the TSD for the Phoenix FIP Rule for Unpaved Parking
Lots, Unpaved Roads and Vacant Lots.
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Comment: MCDOT comments that if Maricopa County were required to
pave all public access unpaved roads within its jurisdiction, as
described by the proposed rule, it would require an expenditure greater
than $100 million, to as much as $300 million, or approximately 5-10
years of the County's total capital improvements budget for
transportation projects. Furthermore, MCDOT asserts that additional
paving of parking lots and compliance by cities and towns within the
County could, in aggregate, be nearly one billion dollars. MCDOT also
claims that there is a substantial maintenance expense in the future
for all roads paved or stabilized, which will create an additional tax
burden.22
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\22\ MCDOT elaborates on this point by claiming that long term
maintenance data indicate that by paving these roads, life cycle
maintenance costs will increase by a factor of five. MCDOT estimates
that chemical stabilization will triple the maintenance cost of
these roadways.
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Response: The final FIP rule does not require the County to pave
all of its unpaved roads. The FIP rule requires RACM for unpaved roads
with greater than 250 ADT (increased from 150 ADT in the proposed FIP
rule). Compliance options include methods of stabilization that are
less costly than paving.
As discussed above and in the proposed FIP's Regulatory Flexibility
Analysis, the FIP rule does not impose any additional compliance burden
beyond that required by Rule 310. Thus, even without the FIP rule, EPA
believes that EPA, a citizen, the State and the County could enforce
under Rule 310 control measures that are more stringent than those
required under the FIP rule.
Because EPA had to develop the FIP rule within the court-ordered
schedule, EPA was limited in the cost data available to the Agency for
the economic feasibility analysis prong of the RACM criteria. See EPA's
response to the previous comment. Unfortunately, while commenters on
the proposed FIP rule provided conclusions as to what they deemed to be
unreasonable compliance costs, they supplied no supporting data.
Therefore, EPA was unable to use this information to refine its
determination of the RACM level of control.
Comment: The City of Mesa and MCDOT maintain that local governments
should have the autonomy to target unpaved roads that are determined
through local study and evaluation to significantly contribute to local
or regional PM-10 levels and develop schedules for paving or
stabilizing those roads with the greatest potential to decrease PM-10
emissions.
Response: In meeting the RACM requirements of the CAA, states are
free to select the mechanisms they deem to be the most appropriate.
Such decisions routinely involve evaluations of the concerns of local
governments. While EPA has not approved Rule 310 as meeting the Act's
RACM requirements for the unpaved road, unpaved parking lot and vacant
lot source categories, clearly that rule was intended to provide a
County-wide RACM regulatory scheme. If MCESD and the State believe that
the rule can be modified to address the concerns raised by the City of
Mesa, Maricopa County or other local jurisdictions, it is free to do so
and EPA will determine whether the rule as modified represents RACM and
can replace the FIP rule. In making this determination, EPA would
evaluate information submitted by MCESD in the staff report
accompanying the rule justifying why the rule as modified represents
RACM.
In developing the FIP rule, EPA was constrained by a number of
factors that necessitated a single approach to implementing RACM for
the entire Phoenix nonattainment area. For example, EPA's San Francisco
office must be able to enforce the rule throughout the nonattainment
area and inform regulated parties of the rule's requirements. Resources
for public outreach would be inadequate should EPA need to administer
RACM differently from one jurisdiction to another. Moreover, even if
EPA could administer a rule that specifies a different RACM level of
control for the numerous jurisdictions within the Phoenix nonattainment
area, EPA lacks the detailed information it would need to do so.
Furthermore, as noted above, such information has not been forthcoming
in responses to the FIP proposal.
Comment: MCDOT, ADEQ and the Arizona Chamber of Commerce all
comment on the issue of legal responsibility for compliance with the
proposed FIP rule's requirements for unpaved roads. The Chamber claims
that the definition in Sec. 52.128(b)(17) of ``unpaved road'' as
``those * * * owned by any federal, state, county, municipal or other
governmental or quasi-governmental agencies' will cause prohibitively
expensive disputes over ownership between private and public entities
and, due to its vagueness, could include more than 100,000 roads in the
County. The Chamber also comments that local governments do not have
the financial resources to decide ownership and to implement RACM.
MCDOT notes that there is no definition of ``ownership'' and that in
some contexts the proposed rule refers to ``owner/operator'' and in
others, strict legal ownership. In this connection, MCDOT states that
ninety percent of the unpaved, public access roads it maintains in the
nonattainment area are not in public ownership. ADEQ makes a similar
point and believes that the FIP's requirements should apply only to
publicly-owned roads.
Response: EPA's intent in proposing the requirements for unpaved
roads was to ensure that responsible entities apply RACM to control
these fugitive dust sources. As stated in the proposed rulemaking, EPA
intended to accomplish this goal by making the requirements of the FIP
rule essentially mirror those of MCESD's Rule 310. Because Section 312
of Rule 310 is very broadly drafted, EPA attempted in its
[[Page 41337]]
proposal to narrow those responsible for compliance to owners or
operators of the pollution sources. In order to rectify the confusion
perceived by the commenters, EPA has amended the final rule to add the
word ``maintains'' in the definition of ``owner/operator'' in
Sec. 52.128(b)(10) and to add the words ``or operated'' in the
definition of ``unpaved road'' in Sec. 52.128(b)(17).
EPA does not believe that the purpose of the FIP's unpaved road
requirements is served by limiting them to those sources that are
publicly owned, particularly in view of the statistics provided by
MCDOT and ADEQ. Therefore, EPA has also removed the word ``public''
from the definition of ``unpaved road'' in Sec. 52.128(b)(17) and,
consequently, from the RACM requirements for unpaved roads in
Sec. 52.128(d)(2). Thus the final rule applies to unpaved roads that
are open to public access, but are privately or publicly owned. These
changes are intended to clarify that both owners, and operators,
including those who conduct roadway maintenance, are legally
responsible for complying with the RACM requirements of
Sec. 52.128(d)(2).23
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\23\ EPA routinely requires that those responsible for operation
and maintenance of a source comply with emission or performance
standards established under the CAA. See CAA section 302(k) and (l).
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In response to comments regarding the vast number of roads
implicated by the proposed RACM requirements, and the concomitant
compliance costs, EPA has changed the ADT threshold in
Sec. 52.128(d)(2) from 150 to 250 and limited the sources to which that
section's requirements apply to those portions of an unpaved road
located within the Phoenix PM-10 nonattainment area.
Comment: MCESD comments that a 0.10 acre threshold is appropriate
at which to expect the application of controls. However, MCESD believes
that enforcement on vacant lots should be reactive (i.e. complaint
driven) for sites less than a threshold of 10 to 50 acres and proactive
on larger sites. However, weed abatement operations that are permitted
will be inspected under Rule 310. The inability to know when a vacant
lot has been disturbed significantly reduces the cost-effectiveness of
a proactive enforcement program for vacant lots. The amount of time
spent checking undisturbed vacant lots adds little value to efforts to
reduce particulate pollution. In addition, MCESD recommends that EPA
refine what level of enforcement and/or implementation represents RACM
and which represents BACM. MCESD cites as an example that their
contacts with Coachella Valley area cities referenced in EPA's proposal
and the TSD established that their vacant lot provisions are enforced
on a complaint-only basis.
Response: In its proposed action on the microscale plan, EPA
proposed to find that the plan did not assure implementation of either
RACM or BACM as required by CAA sections 189(a)(1)(C) and 189(b)(1)(B)
and to disapprove the RACM/BACM demonstrations for the unpaved parking
lots, unpaved roads, and vacant land source categories. This proposed
disapproval was based on the County's enforcement of Rule 310 for these
source categories on a complaint-basis only. See 62 FR 31025, 31034-
31035. MCESD did not make the comments it now advances in connection
with EPA's proposed action on the microscale plan. On August 4, 1997,
EPA took final action to disapprove the microscale plan provisions for
implementing RACM and BACM for these sources. 62 FR 41856, 41862.
While EPA considered dust control rules for other areas, RACM and
BACM determinations are made on a case by case basis. See e.g., 57 FR
13498, 13540, 13561; and 59 FR 41998, 42010 (August 16, 1994).
Therefore, the South Coast Air Quality Management District's approach
to dust control in Coachella Valley is not determinative of what
constitutes the implementation of RACM or BACM for the Phoenix
nonattainment area. As demonstrated in EPA's action on the microscale
plan, implementation of Rule 310's vacant lot provisions on a complaint
basis is not sufficient to prevent these sources from contributing
substantially to exceedances of the PM-10 NAAQS in the Phoenix area.
See 62 FR 31025, 31031. Furthermore, RACM and BACM are levels of
emission reduction control. See 59 FR 41998, 42010. In contrast, the
resources allocated for, and the method and frequency of, enforcement
are the means of ensuring that such emission reductions occur, but are
not themselves control levels.
The provisions of Rule 310 require that RACM, as specified in the
rule, be implemented for the unpaved parking lots, unpaved roads and
vacant land source categories. Having adopted such a rule, the County
has notified the affected parties that they must comply with the rule's
requirements and must ensure that it has the resources and a program
for ensuring that compliance occurs. See CAA section 110(a)(2).
Moreover, since the County has purported to define what constitutes
RACM by the terms of its rule, it cannot then fail to ensure that those
measures are comprehensively enforced and still meet the requirement to
implement RACM in CAA section 189(a)(1)(C). If MCESD believes that Rule
310 as adopted represents a level of control for certain sources that
is beyond RACM or BACM, it is free to modify the rule and submit it to
EPA with the appropriate justification. EPA will then evaluate the
submittal for compliance with the CAA's RACM/BACM requirements.
Comment: ACOC comments that the vacant lot ``Disturbed Surfaces''
provision of the proposed FIP rule would impose a huge economic burden
on homebuilders and private landowners due to the fact that any amount
of disturbed surface area left vacant for more than fifteen days is
subject to the rule. Also, the average private citizen would likely be
unaware of this requirement.
Response: Since there is a de minimis vacant lot size, it is not
true that any amount of disturbed area is subject to the rule. In the
final rule, EPA has increased the de minimis threshold from 0.10 to
0.50 acre of disturbed surface for stabilization of disturbed surfaces.
In any case, the rule does not pose a huge economic burden on
homebuilders; homebuilders need to receive a permit under Maricopa
County Rules 200 and 310 for earth-moving operations over 0.1 acres,
and are therefore not regulated under the FIP rule. However, should
homeowners prepare vacant property for construction by scraping and
leave the surface disturbed for over 15 days prior to construction and
permit applicability, they are subject to the FIP rule. EPA based the
fifteen-day time period on language in MCESD's Rule 310 and believes it
is appropriate as the disturbed vacant lot will be a continual dust
source until re-stabilized. EPA plans to provide outreach assistance to
vacant lot owners within the first eight months following the effective
date of the final rule prior to the required RACM implementation
deadline in order to increase awareness of the FIP rule and its
requirements.
FIP Rule Requirements. De Minimis Levels.
Comment: Several commenters state that the requirement in the
proposed FIP rule to pave all public roads with 150 ADT is
unreasonable. Commenters believe that the 150 ADT threshold is
arbitrary, includes too many roads and is economically burdensome.
Response: EPA believes that a higher ADT threshold is warranted and
represents a RACM level of control. Therefore, in the final FIP rule,
EPA has increased the ADT threshold from 150
[[Page 41338]]
to 250. This higher ADT threshold will relieve some of the cost burden
on public entities, while targeting the roads that cause the most PM-10
emissions. The final rule, with the 250 ADT threshold, will control
dust on roads which receive two vehicles every five minutes, on
average, throughout primary driving hours in a given day rather than
one vehicle every five minutes. EPA, through a contractor, will by the
end of 1998 acquire more data on the sources subject to the FIP rule,
including unpaved roads and their ADT. Should EPA determine in the
future, based on additional information, that the final FIP rule
requirements do not represent a RACM level of control for the Phoenix
area, the Agency will propose appropriate revisions to the FIP.
Comment: The Grand Canyon Council of the Boy Scouts of America
comments that the FIP rule should provide a de minimis use level below
which requirements are not triggered. The Council claims that the
proposed FIP's unpaved parking lot provision does not allow reduced
compliance for lots that receive relatively little heavy use during the
year (but are used more than 35 days a year). The Council suggests a de
minimis level of ingress by fewer than 10 or 25 vehicles per day.
Response: In the final rule, EPA addresses the Council's concern by
establishing an exempted use level for unpaved parking lots of 10
vehicles a day or less. Furthermore, since there are a number of
unpaved parking lots significantly larger than 5,000 square feet where
parking occurs only in a few localized areas, in the final rule, the
owner/operator is only required to implement RACM on the portion of a
lot (as opposed to the entire lot) on which vehicles park.
Notwithstanding regular use of an unpaved parking lot by 10 or fewer
vehicles, the rule offers flexibility for lots used no more than 35
days a year to require RACM controls only if over 100 vehicles park on
the lot and only for the duration that the vehicles are parked.
Comment: MCESD comments that the 0.10 acre threshold for vacant
lots is an appropriate threshold at which to expect application of
controls, but that it is not reasonable to enforce all vacant lots at
this level, except for weed abatement operations. Several other
commenters suggest that a de minimis level of 0.10 acre for vacant lots
is too small. Commenters also state that the regulatory burden on small
residential property owners would be too high and that disturbed static
lots do not contribute significantly to PM-10 compared to disturbed
sites with active earth-moving operations. Commenters suggest that the
de minimis level be increased to one or five acres.
Response: In the final rule, EPA has increased the RACM
implementation de minimis threshold for vacant lot requirements
concerning weed abatement and disturbed surface from 0.10 acre to 0.50
acre. The final rule's de minimis threshold of 0.50 acre is responsive
to commenter's concerns to focus the FIP rule on larger disturbed
areas; however, EPA does not believe a de minimis level greater than
0.50 acres is warranted given MCESD's belief that weed abatement
disturbing 0.1 acres merits control. Since the majority of vacant lot
disturbances are caused by weed abatement and an uncontrolled weed
abated lot would be covered by the requirements for disturbed surfaces,
EPA believes there is a need for consistency between the weed abatement
requirement and the disturbed surfaces requirement. Thus, EPA believes
that a 0.50 acre de minimis level is appropriate.
EPA does not believe that the regulatory burden of the FIP rule
will be high on small residential property owners as the majority of
residential property owners have homes on their property. The FIP rule
does not apply unless the property is vacant and disturbed. Moreover,
the FIP rule only applies where a vacant property's disturbed surface
area is greater than the exemption levels. Where the FIP rule does
apply, property owners have a number of RACM from which to choose,
including lower cost alternatives such as re-vegetation and watering.
In some cases, vacant lots naturally re-stabilize with rainfall to form
a crust or they contain sufficient amounts of aggregate materials or
vegetation such that the standards set forth in the FIP rule are met.
For these reasons, EPA believes the commenters have over-estimated the
regulatory impact of the FIP rule on vacant lot owners. Finally, as
discussed in EPA's responses to comments regarding the cost impacts of
the FIP rule, because all of the RACM discussed above and found in the
FIP rule are already required by Maricopa County's Rule 310, the final
FIP rule does not impose any additional regulatory burden beyond Rule
310.
Compliance Deadlines. Comment: The City of Phoenix comments that
the final rule should move the compliance deadline for disturbed
surfaces on vacant lots from eight months after the effective date of
the rule to June 10, 2000. The City claims this is needed in order to
ensure that property owners become aware of the rule and to implement
dust control measures.
Response: EPA believes an eight-month period of time is sufficient
to conduct public outreach to vacant lot owners regarding FIP rule
requirements to stabilize property or erect barriers. EPA plans to
provide outreach assistance to vacant lot owners within the first eight
months following the effective date of the final rule prior to the
required RACM implementation deadline in order to increase awareness of
the rule and its requirements. The only reason the RACM deadline for
public unpaved roads is June 10, 2000 is due to EPA's recognition that
public entities require additional time to budget funds to implement
RACM. EPA believes that the majority of vacant lots with disturbed
surfaces can be stabilized (unless further disturbed) by applying water
or re-vegetating, thus, a long time-frame for implementing RACM is
unwarranted. Notwithstanding the initial eight-month time frame for
RACM implementation, the final rule requires that RACM be implemented
within two months following a disturbance.
Comment: MCDOT and MCESD comment that the June 10, 2000 deadline
for RACM to be implemented on roads with 150 ADT or more is not
feasible due to the large amounts of material and/or chemicals needed
and the time needed to complete roadway design, right-of-way
acquisition and construction. They state that no other attainment area
has been required to establish a deadline for completion of
stabilization of unpaved surfaces. MCESD and ADEQ suggest that a more
appropriate and realistic compliance target should be an established
schedule that extends beyond June 2000 for treating public unpaved
roads using ADT to establish priorities.
Response: Since EPA has increased the ADT threshold to 250 in the
final rule, there will be fewer roads which require controls under the
FIP rule by June 2000. The June 10, 2000 deadline has not been
established by EPA arbitrarily. As discussed in the proposed
rulemaking, the deadline for RACM implementation after the statutory
deadline of December 10, 1993 is as soon as practicable. 63 FR 15920,
15926. EPA does not believe it achieves the purposes of the CAA to
allow long-delayed RACM implementation to extend beyond June 10, 2000
the statutory deadline for the implementation of BACM.
Comment: MCESD, ADEQ and the City of Mesa comment that the proposed
FIP rule's requirement that a dust control plan (DCP) for weed
abatement be submitted 60 days in advance is impractical, given that
there is a fire
[[Page 41339]]
endangerment concern between the time weed abatement public notices are
issued and a 60-day lead time to submit a DCP to EPA.
Response: In the final rule, EPA has eliminated the requirement
that DCPs for weed abatement be submitted to EPA for approval. Instead,
the final rule establishes RACM requirements for conducting weed
abatement on vacant lots. The RACM are those dust control measures that
EPA would have expected to see in a DCP. The RACM are written broadly
enough to allow responsible parties flexibility in what measures they
use to control dust, provided that the surface is stabilized
immediately following weed abatement to the standards set forth in the
rule.
Alternative Control Measures (ACMs)
Comment: The City of Mesa comments that the provisions in the
proposed FIP rule for ACMs are unduly burdensome (in that they must be
submitted to EPA for approval). Rather, the City believes that if an
ACM renders the disturbed surface area stabilized without any ancillary
adverse impact, it should be encouraged.
Response: EPA agrees with this comment and, in a proposed amendment
to the final FIP rule, the Agency intends to propose that ACMs be
listed among other RACM in each provision to which they apply. EPA
intends to propose that as long as the ACM meets the test method's
criteria for stabilization and does not involve use of a prohibited
material, prior EPA approval would not be required. Thus, the only ACM
that would be submitted to EPA would be one that does not involve
stabilizing an unpaved surface.
Vacant Lot RACM. Comment: The City of Phoenix comments that EPA
should allow alternatives for controlling dust from vacant lots where
vehicles have caused the disturbed surface in addition to posting signs
or barriers. The City claims that these controls are required
regardless of the severity of the disturbance or implementation of
other dust control measures, such as gravel.
Response: In the final FIP rule, EPA adds gravel and chemical/
organic stabilizers to the list of RACM in the ``Motor Vehicle
Disturbances'' provision. Therefore, a vacant lot owner may comply with
both the ``Disturbed Surfaces'' and ``Motor Vehicle Disturbances''
requirements by applying one control measure. Applying gravel or
stabilizers are the only RACM specified in the rule modification since
other control measures listed under the ``Disturbed Surfaces''
requirement do not ensure dust control should further vehicle trespass
occur.
Comment: Several commenters question the technical justification
for a 2-inch gravel requirement, suggesting that two inches of gravel
may not be necessary in all cases to control particulate matter
sufficiently.
Response: EPA has eliminated reference in the FIP rule to 2 inches
of gravel. Since the final rule requires that gravel be applied and
maintained to a sufficient extent necessary to result in a stabilized
surface, the test method will be the sole indicator of whether a source
is sufficiently graveled.
Test Methods. Comment: MCESD and the City of Mesa comment that the
proposed visible crust test method for vacant lots would not be
appropriate since local native soil crusts may crumble easily and
measure less than 0.6 centimeters in thickness, yet still form a
protective surface. ACOC and the Salt River Project (SRP) also question
the scientific substantiality of the proposed visible crust test
method.
Response: In response to comments on the FIP proposal, EPA recently
conducted the proposed test methods on sources in the Phoenix non-
attainment area. As a result of the findings, in a forthcoming proposed
amendment to the final FIP rule, EPA will propose a new test method for
visible crusts that involves dropping a small steel ball from a height
of one foot and checking for pulverization of the surface. EPA believes
that this new method allows a higher degree of replicability than the
existing visible crust test method and is a better indicator of whether
the crust is sufficiently protective given variations in soils.
Comment: Several commenters mention that the requirement in the
proposed FIP rule that the visible opacity of vehicles be tested at a
specific speed on unpaved roads and unpaved parking lots is impractical
and may be unsafe/illegal.
Response: EPA has eliminated the speed limit requirement in the
final rule. In a forthcoming proposed amendment to the final FIP rule,
EPA will propose a new test method for unpaved roads and unpaved
parking lots that involves collecting a surface sample as opposed to
conducting a visible opacity test at a certain vehicle speed.
Comment: Several commenters suggest that the proposed test methods
are too complex to be understood and utilized by property owners who
must comply with the rule.
Response: EPA has eliminated the speed limit requirements from the
test method in the final rule. In its forthcoming proposed amendment to
the final FIP rule, EPA will propose to eliminate the opacity test
method for visible emissions from unpaved roads and unpaved parking
lots. The opacity test method requires opacity readings to be taken by
persons certified in visible emissions training. EPA agrees that this
test method is too complex for most property owners to attempt.
Regarding the remaining test methods in the final rule, EPA believes
much of the perceived complexity is a result of technical language
which is necessary to ensure the test methods are enforceable. A
certain minimum amount of complexity is necessary to ensure that the
test methods can be repeated by more than one individual consistently
and accurately, as well as to ensure that they do not result in over-
controlling sources. EPA plans to provide outreach assistance to
property owners which will explain the test methods in layman's terms
and provide information on the commercially available resources needed
to conduct them.
Enforcement of FIP Rule. Comment: ACLPI states that while it
supports EPA's proposal to provide more enforcement resources for Rule
310, the staff provided will still be grossly inadequate. ACLPI notes
that EPA does not explain why just two additional inspectors will be
adequate. ACLPI states that the Governor's Air Quality Strategies Task
Force in 1998 preliminarily recommended that the County add 9 new
positions for Rule 310 enforcement and that, to comply with the RACM
mandate, Maricopa County must have the same or better enforcement
resources than other air districts which have enforcement staffs of
such size (or larger). ACLPI also claims that EPA's proposal also fails
to provide the legal resources necessary to enforce against violators
detected by the inspectors and believes that the FIP should require the
County (or EPA) to have a full time attorney to conduct enforcement
cases under Rule 310.
While welcoming EPA's proposal to provide additional enforcement
resources, ACLPI urges that the Agency take steps to ensure that such
action does not encourage continuing and repeated avoidance by the
County of its obligation to provide these enforcement resources. ACLPI
asserts that one appropriate step would be for EPA to impose mandatory
or discretionary sanctions on the County for its failure to adequately
fund Rule 310 enforcement and suggests that if this or other steps are
not taken, local and state governments will underfund the programs and
wait for EPA to impose a FIP that includes federal enforcement dollars.
[[Page 41340]]
Response: EPA would like to clarify at the outset that the
discussion in the proposed rulemaking to which ACLPI refers addressed
the Agency's compliance approach for the proposed FIP rule, and not
Rule 310. Thus, to the extent that ACLPI's comments are directed to the
inadequacy of Maricopa County's program for Rule 310 enforcement, they
are not germane to this rulemaking.24 In particular, ACLPI's
remarks regarding inspection and enforcement resource levels for Rule
310 are entirely inapplicable. The statistics ACLPI cites from the
Governor's Task Force Report relate to resources for the entire
universe of sources, both permitted and unpermitted, regulated under
Rule 310. The scope of the FIP rule, however, is considerably narrower
than that of Rule 310 in that it only addresses vacant lots, unpaved
parking lots, and unpaved roads, all fugitive dust sources not
permitted under Rule 310.25
---------------------------------------------------------------------------
\24\ That said, EPA agrees that the resources devoted by the
County to compliance with Rule 310 are inadequate with respect to
unpermitted sources and made such a finding in its action on the
State's microscale plan. 62 FR 41856, 41860. In a March 10, 1998
letter to Al Brown, Director, MCESD, EPA stated that to replace the
FIP rule, MCESD must submit, as a SIP revision, a credible Rule 310
enforcement strategy that demonstrates that the County has adequate
resources of its own to ensure that Rule 310 is fully implemented
for all fugitive dust sources. In this regard, EPA supports the
additional resource levels recommended by the Governor's Task Force
and understands that MCESD is in the process of trying to obtain
them for the purpose of fully implementing Rule 310.
\25\ The statistics ACLPI cites on the enforcement resources of
other air districts represent the total number of inspectors for
each of these districts to conduct all air quality inspections for
all pollutant sources. Therefore, these staffing levels cannot be
used as evidence that MCESD underfunds its fugitive dust program.
---------------------------------------------------------------------------
To the extent that ACLPI's judgments may call into question the
adequacy of EPA's enforcement of its own rule, EPA would like to
clarify its FIP compliance program in two respects.26 First,
in implementing the FIP rule, EPA is constrained by the remote location
of its Regional Office in San Francisco. Because of that constraint,
EPA believes that its compliance program for the FIP rule will benefit
substantially by some kind of local presence. Therefore, EPA will be
funding two inspectors to be provided to MCESD for fiscal year 1999
(October 1, 1998 through September 30, 1999). The primary
responsibility of these inspectors will be to ensure compliance with
the FIP rule.27 If the FIP rule remains in place after
September 1999, continuation of these inspector positions will depend
on whether additional funding can be secured by EPA.
---------------------------------------------------------------------------
\26\ The program is discussed further in the FIP proposal at 63
FR 15920, 15938-15939.
\27\ Nevertheless, these two inspectors will also have the
opportunity to identify and report Rule 310 violations. Thus they
will be able to provide some incidental assistance to MCESD's Rule
310 compliance efforts.
---------------------------------------------------------------------------
Second, as discussed in the proposed rulemaking, in addition to the
two inspectors assigned to MCESD, the Agency will have at its disposal
legal and technical personnel from its San Francisco office to ensure
compliance with the FIP rule by conducting periodic joint inspections
with MCESD and undertaking enforcement actions.
Finally, EPA is somewhat perplexed by ACLPI's suggestion that, in
the absence of federal CAA sanctions, local and state governments will
underfund their Rule 310 enforcement program and wait for EPA to impose
a FIP with federal enforcement dollars. As just explained, EPA is not
in the FIP providing either funding or positions for the benefit of
MCESD. Moreover, it has been the Agency's experience that the specter
of an active federal presence in local affairs acts as a powerful
motivator, a view that ACLPI itself has historically advanced. Indeed,
the recent adoption of State legislation regulating PM-10 emissions
from agricultural activities is evidence of such an effect.
C. Impracticability Demonstration
The CAA requires moderate PM-10 nonattainment areas to demonstrate
attainment of the PM-10 annual and 24-hour standards, or to show that
attainment by the statutory deadline is impracticable. See section
189(a)(1)(B). For this FIP, EPA has demonstrated that existing State
controls, together with the RACM being promulgated by EPA, are not
sufficient for attainment of either the 24-hour or the annual PM-10
standard by December 31, 2001.28
---------------------------------------------------------------------------
\28\ Under CAA section 189(c)(1), the moderate area attainment
deadline was December 31, 1994. The Phoenix nonattainment area is
now classified as serious. As a result, for the purposes of this
moderate area FIP and the State's serious area SIP, the attainment
deadline is December 31, 2001. CAA section 189(c)(2).
---------------------------------------------------------------------------
1. Annual Standard
EPA based its annual standard attainment analysis on air quality
modeling for the 1995 year performed by the Maricopa Association of
Governments for Phoenix serious area PM-10 plan that is currently under
development. See 63 FR 15920, 15939.
As can be seen in Table 2, even assuming 100 percent control for
sources subject to the FIP rule and the commitment for the agricultural
sector (an unrealistic level of control; actual control levels will be
less), simulated concentrations are still over the annual standard of
50 ``g/m\3\. Thus, pursuant to CAA section 189(a)(1)(B), EPA
is finding that attainment of the annual PM-10 standard by December 31,
2001 is impracticable with the implementation of RACM.
Table 2.--Annual Standard Impracticability Demonstration
------------------------------------------------------------------------
Concentration Concentration
after SIP Maximum after FIP
Source category controls possible controls
g/ control g/
m\3\ (percent) m\3\
------------------------------------------------------------------------
Paved road dust.............. 20. ........... 20.0
Unpaved road dust............ 2.9 100 0.0
Gasoline and Diesel vehicle
exhaust..................... 1.2 ........... 1.2
Agricultural dust............ 0.2 100 0.0
Other area sources........... 1.4 ........... 1.4
Residential wood combustion.. 0.4 ........... 0.4
Construction/earth moving.... 5.4 ........... 5.4
Construction equipment,
locomotives, other non-road
engines..................... 1.4 ........... 1.4
Major point sources.......... 0.2 ........... 0.2
Windblown dust............... 0.4 100 0.0
Anthropogenic Total.......... 33.5 ........... 30.0
Background................... 22 ........... 22
Total.................... 55.5 ........... 52.0
------------------------------------------------------------------------
[[Page 41341]]
2. 24-hour Standard
EPA based its 24-hour standard attainment analysis on air quality
modeling of exceedances at four monitoring sites that was performed by
ADEQ for the microscale plan. The four monitoring sites are: (1) Salt
River, in an industrial area; (2) Gilbert, affected by agricultural and
unpaved parking lot fugitive dust emissions; (3) Maryvale, with
disturbed cleared areas nearby due to construction of a park; and (4)
West Chandler, near a highway construction project. These sites were
selected to represent a variety of conditions within the Maricopa
nonattainment area. See 63 FR 15920, 15939.
The microscale plan demonstrated attainment at the Salt River and
Maryvale sites, and EPA approved the attainment demonstrations at these
sites at the time it took final action on the microscale plan. 62 FR
41856, 41862. The microscale plan did not demonstrate attainment at the
West Chandler and Gilbert sites. These sites are addressed here.
The FIP rule requires RACM for unpaved roads, vacant lots, and
unpaved parking lots. These sources in total contribute 25 percent of
the emissions to the exceedance at the Gilbert site and just 1 percent
of the emissions to the exceedance at the West Chandler site. The FIP
rule has a substantial impact for the Gilbert site, reducing ambient
concentrations from 213 to 176 ``g/m3 but much less
effect at West Chandler, reducing concentrations from 332 to just 316
``g/m3. See Table 3. Because the FIP rule does not
result in attainment at either site, EPA is finding that attainment of
the 24-hour standard is impracticable with the implementation of RACM.
As can be seen from Table 3, attainment at both sites will require
substantial reductions from agricultural sources in addition to
reductions from unpaved roads, unpaved parking lots, and vacant lots.
While reductions from agricultural sources are expected through the
implementation of BMPs by 2001, EPA is unable to quantify the impact of
these BMPs at this time because they have not yet been developed.
Therefore it is not possible to determine an expected level of control.
Once the BMPs have been defined, EPA will be better able to estimate
reductions from agricultural sources and will revisit this
impracticability demonstration for the 24-hour standard and modify the
demonstrations as necessary.
Table 3--Impracticability Demonstration for the 24-hour PM-10 Standard
----------------------------------------------------------------------------------------------------------------
Concentration after SIP Concentration after FIP
controls g/m3 FIP control controls g/m3
Source category ---------------------------- (percent) ---------------------------
Chandler Gilbert Chandler Gilbert
----------------------------------------------------------------------------------------------------------------
Agricultural fields........................ 194.7 ............ ........... 194.7
Agricultural aprons........................ 21.7 55.6 ........... 21.7 55.6
Road construction.......................... 6.9 ............ ........... 6.9
Unpaved roads.............................. 0.5 0.5 64 0.2 0.2
Paved Roads................................ 0.2 1.6 ........... 0.2 1.6
Unpaved parking lots....................... ............ 51.3 56 ............ 22.6
Vacant lots................................ 28.1 14.5 56 12.4 6.4
Anthropogenic Total........................ 252.1 123.4 ........... 236.1 86.3
Background................................. 80 90 ........... 80 90
--------------------------------------------------------------------
Total.................................. 332.1 213.4 ........... 316.1 176.3
----------------------------------------------------------------------------------------------------------------
See section IV.D. below for a discussion of the estimated emission
reductions from the FIP control measures.
EPA received a number of comments on the proposed impracticability
demonstrations. The most significant comments have been addressed below
and all comments have been fully addressed in the Response to Comments
TSD.
Comment: ACLPI comments that EPA's impracticability demonstration
is flawed because it does not include all RACM and uses an unapproved
state model. ACLPI asserts that EPA's failure to include so called ``de
minimis'' measures in the FIP, as well as the other measures the Agency
has excluded from the FIP, could very well make the difference between
the showing of impracticability and a showing of attainment. ACLPI
notes that under the analysis in Table 5 of the proposed rulemaking,
the FIP measures could reduce annual PM-10 levels to 52 g/
m3--only 2 g/m3 over the standard and
yet EPA's ``de minimis'' policy allows the Agency to avoid adopting any
measures that produce less than 1 g/m3 in
improvement and thus, an additional package of ``de minimis'' measures
could well make the difference between attainment and nonattainment.
Based on the data in Table 2 of the proposed rulemaking, ACLPI asserts
that, combined, the ``de minimis'' sources in that table would reduce
PM-10 by 4.0 g/m3 on an annual basis--more than
enough to produce attainment based on the data in Table 5 of the
Proposed rulemaking. The Center concludes that far from showing
impracticability, EPA's analysis shows that timely attainment is
practicable with the adoption of additional measures that are already
identified and for which there is no reasoned justification to reject.
Response: EPA believes that ACLPI's comment addresses only the
impracticability demonstration for the annual standard and is
responding to it on that basis. As noted above, EPA used the State's
modeling as the technical basis for this FIP. As such, the modeling was
subject to public comment as part of the FIP proposal and did not
require a prior CAA section 110(k) approval for EPA to use it. EPA also
demonstrated that it has included all RACM available to it in the
impracticability demonstration. See section IV.A.
The projected 52 g/m \3\ concentration in Table 5 of the
proposed rulemaking assumes complete elimination of emissions from
unpaved roads, agricultural dust, and windblown dust--an unrealistic
level of control. See 63 FR 15920, 15939. There is currently
insufficient information to accurately calculate regional reductions
from the FIP measure for unpaved parking lots, vacant lots, and the
commitment for agricultural controls. By showing that attainment would
still not result even with 100 percent control on these sources, EPA
was able to find that attainment of the annual standard is
impracticable with the implementation of RACM. However, because it was
derived from an assumption of 100
[[Page 41342]]
percent control, the projected 52 g/m \3\ annual level is too
optimistic and the actual concentration after implementation of the FIP
RACM will be higher.
The total impact of all de minimis source categories combined is
3.4 g/m \3\, or less than 10 percent of the exceedance of the
annual PM-10 standard at the Greenwood monitor.29 Attainment
at the Greenwood monitor would require elimination of more than half
the emissions from these sources in addition to eliminating all
emissions from the sources subject to the FIP measures. These de
minimis sources include on-road motor vehicles (already subject to
tailpipe standards, I/M, and clean fuel requirements), residential wood
combustion (already controlled at RACM levels), all other combustion
sources, and major point sources (already subject to RACT). No measures
exist that could reduce emissions from these sources by more than half
by the end of 2001, short of banning or substantially curtailing their
operations; neither option would constitute a reasonable level of
control. A more practicable approach to attaining the standard at
Greenwood is to a obtain the needed emission reductions from the source
categories that contribute significantly to the nonattainment problem
at the Greenwood monitor, source categories such as unpaved road dust
and paved road dust. EPA is promulgating a rule in this FIP to reduce
emissions substantially from unpaved roads and EPA evaluated a large
number of measures to reduce emissions from paved roads (including many
transportation control measures) and found none that were RACM for the
Agency.
---------------------------------------------------------------------------
\29\ The total sum of the impact of the de minimis source
categories listed on Table 2 of the Proposed rulemaking is 4.0
g/m \3\; however, in this FIP both agricultural dust and
windblown dust are considered significant sources because they are
significant sources for the 24-hour standard. As result the total
impact of de minimis sources at the Greenwood monitor is only 3.4
g/m \3\.
---------------------------------------------------------------------------
D. Reasonable Further Progress Demonstrations
As discussed in the proposal, EPA interprets the RFP requirement
for areas demonstrating impracticability as being met by showing that
the implementation of all RACM has resulted in incremental emission
reductions below pre-implementation levels. See 63 FR 15920, 15927.
RFP is demonstrated separately for the annual and 24-hour standards
because in the Phoenix area the mix of sources contributing to the
annual standard exceedances differs from that contributing to the 24-
hour exceedances. In addition, since PM-10 exceedances in the Phoenix
area are related almost entirely to primarily-emitted PM-10, only
emissions of primarily-emitted PM-10 are evaluated for RFP.
EPA has revised the annual standard RFP demonstration from the
proposal to reflect the changes to the FIP fugitive dust rule. Although
EPA does not believe that annual incremental reductions are required to
be shown for moderate PM-10 nonattainment areas demonstrating
impracticability, EPA has also revised the RFP tables (Tables 7, 8, and
9) from the proposal to show that the FIP does, in fact, result in
annual incremental reductions. See section IV.D.1. below.
EPA received a number of comments on its interpretation of the RFP
requirement for areas demonstrating impracticability as well as on the
specifics of the RFP demonstration. EPA responds to the most
significant comments in section IV.D.2. below and to all comments
received in the response to comments TSD found in the docket for this
rulemaking.
1. Revised RFP Demonstrations
a. Annual Standard. EPA has revised the annual standard RFP
demonstration to account for the increased ADT threshold for controls
on unpaved roads in the FIP fugitive dust rule. Revisions to the FIP
rule's provisions for vacant lots or unpaved parking lots did not
affect the annual standard RFP demonstration because no reductions were
assumed from these sources in the proposed demonstration. The final
annual standard RFP demonstration showing incremental reductions
between 1998 and 2001 is presented in Table 4.
Emission levels for 1998, 1999, 2000, and 2001 were calculated by
growing emissions from the emission inventory base year of 1994 and the
modeling year of 1995 based on growth factors provided by MAG and by
incorporating reductions from approved State RACM and BACM controls.
Emissions levels for 2000 and 2001 also reflect the estimated emission
reductions from the FIP rule for unpaved roads. The estimated
effectiveness of controls on unpaved roads, 80 percent, was based on
the research done for the microscale plan on the effectiveness of
controls for unpaved parking (see Table 4-1 in the final microscale
plan) and assumes a rule effectiveness of 80 percent per EPA's guidance
(57 FR 13503). EPA has not changed these estimated control and rule
effectiveness percentages in this final demonstration; however, the
Agency estimates that the increase in the ADT applicability threshold
in the FIP rule will reduce the total unpaved road VMT impacted by the
rule from 90 percent to 50 percent.
The annual standard RFP demonstration did not include emission
reductions from the implementation of the FIP rule for unpaved parking
lots and vacant lots. Although emission reductions are expected from
these sources starting in 1999, there currently is insufficient
information on the number of unpaved parking lots and vacant lots that
will be subject to the FIP to estimate an emission reduction.
Information from the surveys EPA will perform after promulgation of the
rule will help in quantifying emission reductions from these sources.
In addition, while reductions from agricultural sources are also
expected starting in 2000, no emission reductions were assumed in the
RFP demonstration for agricultural sources because the ultimate RACM
have not been defined and therefore the expected level of control
cannot be determined. Because the reductions expected from vacant lots,
unpaved parking lots, and agricultural sources cannot at this time be
quantified, the showing that the FIP will result annual incremental
reductions is necessarily qualitative.
As can be seen in Table 4, in order to show annual reductions from
1998 to 1999, emission reductions of more than 87 mtpy would need to
result from the implementation of the FIP fugitive dust on vacant lots
and unpaved parking lots. The total regional inventory for unpaved
parking lots is currently unknown. The regional inventory for vacant
lots, however, is estimated to be 2020 mtpy in 1999. See RFP TSD. The
FIP rule will need to reduce emissions in this category by a little
more than 4 percent in order to demonstrate annual incremental
reductions. Because application of dust control measures to a disturbed
surface is expected to reduce fugitive dust from that surface by 56
percent (see 63 FR 15920, 15941), EPA is confident that the rule will
achieve at least a 4 percent overall reduction in regional fugitive
dust emissions from vacant lots sufficient to show reductions in total
regional PM-10 emissions from 1998 to 1999. 30
---------------------------------------------------------------------------
\30\ This conclusion is supported by noting that the estimated
reductions from applying the FIP rule to one vacant lot for one day
at the Chandler monitoring site is 3.5 metric tons per windy day, 4
percent of the total annual reductions needed to show an incremental
reduction from 1998 to 1999.
---------------------------------------------------------------------------
As can be also be seen in Table 4, in order to show annual
reductions from 2000 to 2001, emission reductions of more than 239 mtpy
would need to
[[Page 41343]]
result from the implementation of the BMPs on agricultural sources. The
projected regional inventory for agricultural sources is 6,972 mtpy in
2001. See RFP TSD. The FIP rule will need to reduce emissions in this
category by slightly more than 3 percent in order to demonstrate annual
incremental reductions between 2000 and 2001. Again, EPA has every
confidence that such minimal reductions can be achieved.
Table 4.--RFP Demonstration for the Annual Standard
------------------------------------------------------------------------
Total PM-10 emissions metric
Year tons/year
------------------------------------------------------------------------
1998................................... 61,017.
1999................................... 61,104--reductions from vacant
lots and unpaved parking lots.
2000................................... 57,607--reductions from vacant
lots and unpaved parking lots.
2001................................... 57,846--reductions from vacant
lots, unpaved parking lots,
agricultural sources.
------------------------------------------------------------------------
b. 24-hour Standard. For the 24-hour standard, EPA evaluated RFP
only for the Gilbert and West Chandler sites, having already approved
the RFP demonstrations at the Maryvale and Salt River sites as part of
its action on the microscale plan. 62 FR 41856, 41862.
Changes to the FIP fugitive dust rule do not affect the emission
reductions assumed in the proposed RFP demonstrations for the 24-hour
standard because the rule will continue to apply in the same manner and
to the same extent as was assumed in the proposal. In other words, the
changes to the FIP rule do not affect its application to the sources
surrounding the Gilbert and West Chandler sites.
As with the annual standard demonstration, 1998 emission levels
were adjusted to reflect implementation of the improved controls on
construction sources and 2001 emissions levels to reflect the estimated
emission reductions from the proposed FIP rule for unpaved roads,
unpaved parking lots, and vacant lots. Emission reductions estimates
are again based on the research done for the microscale plan and assume
a rule effectiveness of 80 percent per EPA's guidance. For unpaved
roads, a control effectiveness of 80 percent is assumed. For vacant
lots and unpaved parking lots, a control effectiveness of 70 percent is
assumed. As with the annual standard, no emission reductions were
assumed for agricultural sources. A more detailed analysis of the RFP
demonstrations for the Gilbert and West Chandler monitors can be found
in the RFP TSD.
i. Gilbert Monitoring Site. The 24-hour exceedances at the Gilbert
monitor are impacted by emissions from agricultural aprons, disturbed
cleared lands (i.e., vacant lots), unpaved parking lots, and paved
roads. 62 FR 31025, 31031. As can be seen from Table 5, the emission
reductions from the FIP rule and commitment for unpaved parking lots
and vacant lots and agricultural sources are sufficient to assure
incremental emission reductions between 1998 and 2001 and annual
incremental reductions 31 in the interim years. EPA,
therefore, finds that the FIP assures RFP for the 24-hour standard at
the Gilbert monitor.
---------------------------------------------------------------------------
\31\ While there is no change in total emissions from 1999 to
2000, EPA believes that annual incremental reductions are still
shown because of the large reduction occurring in the early years
between 1998 and 1999.
Table 5.--RFP Demonstration for the 24-hour Standard--Gilbert Monitoring Site
--------------------------------------------------------------------------------------------------------------------------------------------------------
Emissions(kg/day)
Source categories FIP control (%) year -------------------------------------------------------------------------------------
1998 1999 2000 2001
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture aprons............... 0 (2001)....................... 165 165 165 165 (-reductions from BMPs).
Vacant lots...................... 0.56 (1999).................... 76 33 33 33.
Unpaved parking lots............. 0.56 (1999).................... 190 84 84 84.
Paved roads...................... 0.............................. 5 5 5 5.
----------------------------------------------------------------------------------------------------------------------
Total........................ ............................... 436 287 287 287 (-reductions from BMPs).
--------------------------------------------------------------------------------------------------------------------------------------------------------
ii. West Chandler Monitoring Site. The 24-hour exceedances at the
West Chandler monitor are impacted by emissions from agricultural
fields, agricultural aprons, road construction, disturbed cleared lands
(i.e., vacant lots), unpaved roads, and paved roads. 62 FR 31025,
31032. As can be seen from Table 6, the emission reductions from the
FIP rule for unpaved roads and vacant lots and and the commitment for
controls on agricultural sources are sufficient to assure incremental
emission reductions between 1998 and 2001 and annual incremental
reductions in the interim years; therefore, EPA finds that the FIP
assures RFP for the 24-hour standard at the West Chandler monitor.
Table 6.--RFP Demonstration for the 24-hour Standard--West Chandler Monitoring Site
--------------------------------------------------------------------------------------------------------------------------------------------------------
Emissions (kg/day)
Source category FIP control (%) Year ---------------------------------------------------------------------------------------
1998 1999 2000 2001
--------------------------------------------------------------------------------------------------------------------------------------------------------
Agriculture..................... 0 (2001)...................... 19378 19378 19378 19378 (-reductions from BMPs).
Vacant lots..................... 0.56 (1999)................... 6188 2723 2723 2723.
Road Construction............... 0............................. 440 440 440 440.
Agricultural apron.............. 0 (2001)...................... 1954 1954 1954 1954 (-reductions from BMPs).
Unpaved road.................... 0.64 (2000)................... 49 49 18 18.
Paved roads..................... 0............................. 37 37 37 37.
-----------------------------------------------------------------------------------------------------------------------
Total....................... .............................. 28046 24581 24550 24550 (-reductions from BMPs).
--------------------------------------------------------------------------------------------------------------------------------------------------------
[[Page 41344]]
2. Response to Comments on the RFP Demonstration
EPA has responded to the most significant comments on the proposed
RFP demonstration below. The TSD contains EPA's response to all
comments received.
Comment: ACLPI asserts that section 172(c)(2) of the Act
specifically requires all nonattainment area SIPs to show RFP, and that
both the Act and longstanding EPA guidance require that, to satisfy the
RFP requirement, plans must provide for annual reductions in total
emissions sufficient to produce steady progress toward attainment on a
straight line basis or faster, citing CAA section 171(1) and 59 FR
41988, 42016 (August 16, 1994); 52 FR 45044, 45066 (November 24, 1987);
46 FR 7182, 7185 (January 22, 1981); EPA, Guidance Document for
Correction of Part D SIP's for Nonattainment Areas (January 27, 1984).
ACLPI disagrees with EPA's claim that for moderate areas demonstrating
impracticability, the Act's RFP requirement is met by a showing that
implementation of all RACM will result in ``incremental emission
reductions below pre-implementation levels.'' ACLPI asserts that the
Act does not in any way waive the RFP requirement for moderate PM-10
areas claiming impracticability and explicitly sets out RFP as a
requirement separate, distinct and in addition to RACM, comparing
section 172(c)(1)(RACM) with section 172(c)(2)(RFP). ACLPI claims that
EPA's reading of the RFP requirement for areas demonstrating
impracticability would render the RFP mandate a mere redundancy, a
result that is contrary to well-settled rules of statutory
construction, citing N.J. Singer, 2A Statutes & Statutory Constr.
Sec. 46.06 at 119-20 (1992 Rev.).
Response: EPA agrees with ACLPI that the RFP requirement in section
172(c)(2) is a separate and distinct requirement for nonattainment
plans that is in addition to the requirement for RACM in section
172(c)(1). It also agrees that all nonattainment plans must address the
RFP requirement, including moderate area PM-10 plans demonstrating
impracticability. EPA has not waived the RFP requirement and has fully
addressed it in this FIP. See section IV.D.1. Section 171(1) of the CAA
defines RFP as:
[S]uch annual incremental reductions in emissions of the
relevant air pollutant as are required by [Part D of title I of the
Clean Air Act] or may reasonably be required by the Administrator
for the purpose of ensuring attainment of the applicable national
ambient air quality standard by the applicable date.
As seen from this definition, the adequacy of the emission
reductions required to demonstrate RFP is inextricably linked to the
reductions necessary to ensure attainment and thus to the control
strategy necessary for attainment. Because of this interconnection, EPA
has historically required RFP to be demonstrated by showing that
nonattainment plans provide for annual incremental emission reductions
sufficient generally to maintain at least linear progress toward
attainment by the applicable attainment deadline. See, e.g., 43 FR
21673, 21675 (May 19, 1978), Criteria for Proposing approval of
Revisions to [1979] Plans for Nonattainment Areas; 46 FR 7185 (January
22, 1981), Approval of 1982 Ozone and Carbon Monoxide Plan Revisions
for Areas Needing an Attainment Date Extension [under CAA section
172(a)(2)]; 59 FR 41988, 42016 (August 16, 1994), State Implementation
Plans for Serious PM-10 Nonattainment Areas. As described, for example,
in the 1978 guidance document, the required linear reductions were
represented graphically as a straight line drawn from the base year
(i.e., the submittal year for the plan) emission inventory to the
allowable emissions in the attainment year. RFP was shown if the annual
emission reductions were sufficient to produce this ``straight-line
rate.'' 32 See 43 FR 21675.
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\32\ This requirement for reductions on a ``straight-line rate''
has never been absolute. EPA has stated that it would accept less
than a straight-line rate if the State could show that a lag was
necessary to accommodate the time required for compliance. See 43 FR
21675 and 44 FR 20372, 20377 (April 4, 1979). EPA has also noted
that in certain situations, such as where there are a limited number
of sources contributing to the nonattainment problem, where
requiring linear progress reductions in PM-10 emissions to maintain
RFP is less appropriate and in such situations an expeditious
compliance schedule can be used to demonstrate RFP. See 59 FR 41998,
42015.
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Since this straight-line rate demonstration requires a
determination of the emission reductions needed for attainment, the
guidance documents requiring linear progress for RFP in nonattainment
plans has always been predicated on the existence of a concurrent
statutory requirement that the nonattainment plan also demonstrate
attainment. These guidance documents, however, provide little help in
determining how RFP is to be demonstrated when a nonattainment plan is
statutorily allowed not to demonstrate attainment, as is the case with
certain moderate area PM-10 plans.
Moderate area PM-10 plans demonstrating impracticability do not
include a projection of the allowable emissions in the attainment year.
Attainment projections for such areas are not required until submittal
of the subsequent serious area plan. Thus, for moderate plans
demonstrating impracticability, it is not possible to determine the
linear rate of reductions required under the RFP guidance for plans
demonstrating attainment because the line's end point, the allowable
attainment level, is missing. Put simply, EPA's previous interpretation
of and guidance for the RFP requirement in the Act do not work in areas
demonstrating impracticability. In such a situation, it is necessary
and appropriate to amend the previous guidance.33
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\33\ Under CAA section 193, guidance issued by EPA prior to the
1990 CAA Amendments remain in effect except to the extent that it is
inconsistent with any provision of the revised Act or is revised by
the Administrator. As will be seen, EPA has both found that its
previous RFP guidance requiring linear emission reductions is
inconsistent with the statutory provisions allowing demonstration of
impracticability for moderate PM-10 areas and revised that guidance
for such areas.
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EPA issued preliminary guidance on interpreting the RFP requirement
for moderate PM-10 areas demonstrating impracticability in its final
approval of the Phoenix moderate area PM-10 plan, noting that the
guidance was intended to clarify the confusion created by omissions in
the Act and in prior EPA guidance. See 60 FR 18010, 18013 (April 10,
1995). In that notice, EPA stated that RFP was demonstrated by showing
that the implementation of all RACM has resulted in ``incremental
reductions'' in emissions of PM-10. EPA clarified and further explained
this guidance in its proposal to restore the Agency's approval of the
Phoenix moderate area plan. See 61 FR 54972, 54973. As quoted above,
RFP is defined in section 171(1) as either annual incremental
reductions as are required under part D, or such reductions as the
Administrator may reasonably require ``for the purpose of ensuring
attainment of the [NAAQS] by the applicable date.'' In moderate PM-10
area plans demonstrating impracticability, there is no demonstration of
attainment, simply a demonstration that, even after the implementation
of all RACM, it is impracticable for the area to attain the PM-10
standard by the applicable attainment deadline. Once EPA has determined
that all reasonable control measures that are available have been
implemented and timely attainment still will not occur, there are no
further reductions that it would be reasonable to require ``for the
purpose of ensuring attainment'' by the applicable attainment deadline.
Thus, the emissions reductions achieved through
[[Page 41345]]
implementation of all RACM, by definition, would satisfy the
requirement to demonstrate reasonable further progress in the period
before the Act requires a new plan that includes the additional
measures needed to produce the net emissions reductions required for
attainment.
Moreover, EPA's interpretation is reasonable given the Act's scheme
for PM-10 attainment. Among all the Act's numerous nonattainment
requirements, the moderate area PM-10 provisions are unique in
tolerating a planned failure to demonstrate attainment and deferring
the obligation to demonstrate attainment to a later plan. EPA's
interpretation of the general RFP requirement in section 172(c)(2), as
it applies to moderate PM-10 areas demonstrating impracticability, must
not only meet the Act's definition of RFP but must also be consistent
with the statutory scheme for PM-10 attainment. For the reasons stated
above, EPA believes that its interpretation of the RFP requirement for
areas demonstrating impracticability is consistent with this scheme.
Requiring RFP demonstrations to show emission reductions in excess of
those resulting from the implementation of all RACM would conflict with
the CAA section 189(a)(1)(B)(ii) provision for demonstrating
impracticability.\34\
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\34\ EPA's approach is consistent with the rule, long
articulated by the Ninth Circuit, that ``language in one section of
the statute [is to be interpreted] consistently with the purposes of
the entire statute considered as a whole.'' Adams v. Howerton, 673
F.2d 1036, 1040 (9th Cir.), cert. denied, 458 U.S. 1111 (1982). See
also In re Arizona Appetito's Stores, Inc., 893 F.2d 216, 219 (9th
Cir. 1990) (courts to adopt interpretation that is harmonious with
the statute's scheme and general purposes).
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Finally, this entire discussion is somewhat academic in the case of
this FIP where the expeditious application of RACM not only results in
incremental emission reductions below pre-implementation levels, but
also in annual incremental reductions for both the 24-hour and annual
PM-10 standards. See section IV.D.1.
Comment: In its 1996 comments (which the Center requested be
incorporated into its comments on the April 1, 1998 PM-10 FIP
proposal), ACLPI argues that EPA wrongly suggests that the Act's RFP
mandate disappears after the applicable attainment date has passed and
does not reappear until the state submits a new SIP to meet a new
attainment deadline. The Center asserts that under this view, a state
that is delinquent in meeting an attainment deadline can actually do
less to move toward attainment than an area that has yet to miss a
deadline. Given that the whole purpose of the RFP mandate is to assure
steady progress toward clean air, ACLPI argues that the purpose becomes
even more urgent when an area is continuing to violate standards and
that EPA's position is comparable to that rejected by the Court in
Delaney v. EPA, 898 F.2d 687 (9th Cir. 1990). In addition, ACLPI argues
that the approach proposed by EPA could not be more antithetical to the
language and purpose of the CAA and that under such an approach, EPA
could approve a SIP that will actually allow air quality to worsen
since the SIP need only slow the rate of emissions growth until the
attainment deadline but after the attainment deadline, the SIP need not
even slow the rate of emissions growth and emissions can grow at any
rate. ACLPI asserts that it is inconceivable that Congress intended a
result so contrary to the public health goals of the Act, or to the
plain meaning of the phrase, ``reasonable further progress.''
Response: As stated above, the RFP mandate in the Act is intended
to ensure that nonattainment plans provide for reasonable progress
toward attainment by the applicable attainment date, as is clear from
the plain language of the RFP definition in section 171(1) of the Act.
As is apparent from that language, RFP, as the term is used in the CAA,
applies only in the period prior to the applicable attainment date and
does not continue in the period after that date.
ACLPI purports to invest in the RFP mandate the solution to all
potential problems with implementation plans, from delinquent plans and
failure to actually attain the standards, to increasing emissions after
attainment dates have passed. This all-encompassing view of the RFP
mandate ignores the provisions of the Act that Congress added to
specifically address each of these situations: the section 179(a)
sanctions and section 110(c) federal plan requirements for addressing
delinquent or inadequate plans; the reclassification requirements of
sections 181(b)(2), 186(b)(2), and 188(b) (with their accompanying
requirements for new plans in sections 182, 187, and 189) and the
mandatory rate of progress requirements in sections 187(g) and 189(d)
for addressing continuing violations after the serious area attainment
date has passed; the requirement for contingency measures in section
172(c)(9) to assure additional emission reductions after an area fails
to attain but before a new plan is submitted to prevent emissions
growth; and the maintenance plan requirements in section 175(A) to
assure limits on emissions growth to prevent violations of the standard
in areas redesignated to attainment.\35\
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\35\ In light of the new statutory provisions in the 1990 Clean
Air Act Amendments, ACLPI's comment that EPA's position is
comparable to that rejected by the Ninth Circuit in Delaney is
inapposite. In that case, the Court was addressing the consequences
of a lapsed attainment deadline in the absence of any related
statutory provisions. In the 1990 Amendments, Congress provided
specific actions to be undertaken should such a lapse occur.
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Given that there are other specific CAA provisions that address the
hypothetical scenarios ACLPI envisions, there is no basis for invoking
the general RFP provision as a gap-filling, all-purpose remedy for
them. EPA's interpretation of the section 172(c)(2) RFP requirement as
set forth in the FIP is consistent with the statutory purpose of
achieving regular emission reductions as needed to assure attainment by
the applicable attainment date.
Comment: ACLPI comments that the Act's reclassification scheme does
not support EPA's RFP approach because the purpose of reclassification
is to prompt adoption of more stringent controls and not an excuse to
bring progress to a stop.
Response: EPA does not claim that the reclassification scheme
supports its RFP approach. Equally, the reclassification scheme does
not support ACLPI's proposition that the RFP requirement should apply
after an applicable attainment date. As noted previously, the plain
language of the RFP definition clearly indicates that RFP is only
required in the period before the applicable attainment date and not
after it has passed. As also noted previously, the CAA provision
intended to address progress between a lapsed attainment date and the
submittal of a revised nonattainment plan with its new RFP
demonstration is the contingency measures provision in section
172(c)(9).
Comment: ACLPI claims that EPA's RFP analysis for the proposed FIP
is flawed in several other key respects. First, ACLPI asserts that it
is based on an emissions inventory that is not complete, current, and
accurate, as required by the Act. ACLPI states that the inventory
submitted by the state in connection with its 1991/1993 PM SIP revision
showed vehicular exhaust as constituting 36 percent of total PM-10
emissions (ADEQ, Final State Implementation Plan Revision, Revised
Chapter 9 (Feb. 1994) p. 9-34) and in contrast, the inventory relied on
in EPA's current RFP demonstration shows the same sources as amounting
to only 8 percent of the inventory and that EPA offers no rational
explanation for this glaring disparity. ACLPI notes that the State's
prior inventory was based on
[[Page 41346]]
actual speciated monitoring data from the Phoenix area and that EPA's
inventory appears to based on theoretical emission factors and
speculation.
Response: EPA based its RFP analysis for the proposed FIP on the
1994 regional emission inventory prepared by MAG (see 1994 Regional PM-
10 Emission Inventory for the Maricopa County Nonattainment Area, Draft
Final Report, MAG, May 1997) and additional inventory work prepared for
the regional PM-10 modeling (see Technical Support Document for the
Regional PM-10 Modeling in Support of the 1997 Serious Area PM-10 Plan
for Maricopa County Nonattainment Area, Draft, MAG, October 1997).
These inventories were prepared following the procedures in EPA
guidance, using either EPA emission factors or other appropriate
emission factors and Phoenix-specific activity data.
It is not valid to conclude from the mere fact that this inventory
differs in its apportionment of sources from the inventory in the 1991/
93 PM SIP that the regional 1994 inventory is inherently flawed.
Inventories prepared at different times will naturally vary because
improved methodologies are developed, new information about sources is
collected, control measures are implemented, and emission growth rates
vary across categories. All these factors tend to affect the percentage
presence of a source category from inventory to inventory. Because it
is the nature of inventories to change over time, EPA does not normally
require new inventories to be reconciled against previous ones and any
differences between them explained.
The inventory in the 1991/93 PM-10 Plan referred to by ACLPI is the
regional inventory modified (``normalized'') to reflect a 1989-1990
source apportionment at three urban Phoenix monitors: Central Phoenix,
West Phoenix, and South Scottsdale. 36 This source
apportionment was performed using Chemical Mass Balance (CMB) modeling
and monitored speciated data. As work has been done to evaluate the
nature of the PM-10 problem in Phoenix, it has become increasing clear
that PM-10 exceedances in the Phoenix area often have highly localized
causes. In other words, the sources that contribute substantially to an
exceedance are often located close to the exceeding monitor. As a
result, any inventory that is developed based on the source
apportionment from a given monitor or small set of similar monitors is
only truly informative about the relative significance of sources
around those monitors rather than about the relative significance of
sources in a regional inventory.
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\36\ Strictly speaking, this normalized inventory is not an
emission inventory at all, but merely the percent source
contributions at a monitor multiplied by the total regional
inventory as calculated by emission factors and source activity
levels.
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Phoenix has a large number of fugitive dust sources such as
construction sites, vacant lots, unpaved roads, and agricultural
fields. Emissions from these sources need to be included in any
regional inventory. However, as noted in EPA's proposed action on the
microscale plan, fugitive dust PM-10 has more localized effects than
other criteria pollutants because it is emitted near ground level and
has relatively sharp spatial concentration gradients as dust settles
out with distance from the emitting source. See 62 FR 31025, 31030.
Consequently, it would be surprising to see a substantial contribution
from fugitive dust sources at urban monitors where there were
relatively few of these fugitive dust sources close by. The source
apportionment at such monitors is much more likely to be influenced by
local sources such as paved road dust and by fine particulate sources,
such as vehicle exhaust, which tend to remain suspended in ambient air
longer. This is exactly the source apportionment seen at the three
urban monitors used to generate the 1991/93 Plan's normalized
inventory. As a result, it is not surprising to see that the 1991/93
Plan's normalized inventory skewed toward paved road dust and vehicle
exhaust and away from fugitive dust. Basing the regional inventory on
the source apportionment at urban monitors, however, will underestimate
regional fugitive dust emissions. This underestimation is illustrated
in the 1991/93 Plan's normalized inventory in which fugitive dust
sources account for only 3 percent of the total regional PM-10
emissions.
Source apportionment at a monitor is a necessary part of preparing
a PM-10 attainment demonstration because without a clear understanding
of the relative contributions of sources causing an exceedance, it is
impossible to know how controls will affect air quality.37
But in preparing a regional inventory for an area as large and as
diverse as Phoenix, with its many fugitive dust sources, source
apportionment based on just a few urban monitors is unlikely to result
in a regional inventory that correctly accounts for fugitive dust
emissions.
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\37\ In the 1991/93 Plan, the primary purpose of the normalized
inventory was to evaluate the effects of controls for the
impracticability demonstration. See 1991/93 Plan, p. 9-39.
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Comment: ACLPI also asserts that EPA failed to accurately address
growth in PM-10 emissions from vehicular exhaust. ACLPI notes that the
Agency's inventory shows on-road exhaust emissions of PM-10 steadily
decreasing from 1610 tpy in 1995 to 1037 tpy in 2001, but cites a MAG
conformity analysis that shows vehicle exhaust emissions of PM-10
increasing to 8,807 tpy (based on 24.13 tpd) by 2001. ACLPI argues that
increased emissions are consistent with projected increases in VMT and
with the lack of additional controls to limit motor vehicle emissions
of PM-10 and that EPA cannot justify reliance on an inventory that
shows decreasing motor vehicle emissions when this conflicts with
reality.
Response: The MAG conformity analysis is performed using an out-of-
date mobile source emissions model, the 1985 Particulate Model. See
Conformity Analysis, MAG Long Range Transportation Plan Summary and
1997 Update [and] MAG 1998-2002 Transportation Improvement Program,
MAG, November 1997, p. 1-21. MAG uses this model in its conformity
determinations in order to be consistent with the model used in the
State's 1991/93 moderate area plan. In 1994, EPA released the PART5
mobile source model for use in SIPs. As recommended by EPA guidance,
the base and projected exhaust emission inventories in the FIP were
developed using the PART5 model. See PM-10 Emission Inventory
Requirements, OAQPS, EPA (EPA-454/R-94-033), September 1994, p. 14. The
PART5 model changed the estimates of emissions from on-road motor
vehicles. The difference between the conformity and FIP inventories is
partly related to this change in emission models.
The difference between the two inventories is also the result of
the use of the normalized inventory from the 1991/93 PM-10 Plan in the
conformity analysis. Again, MAG uses the normalized inventory to be
consistent with the submitted PM-10 SIP. See Conformity Analysis, p. 1-
20. As discussed in the previous response, this normalized inventory
substantially increased the vehicle exhaust portion of the inventory
based on the source apportionment at three urban monitors. This
normalized inventory does not accurately reflect the contribution of
fugitive dust sources to the regional inventory and probably overstates
vehicle exhaust emissions.
Because the motor vehicle exhaust inventory in the MAG conformity
analysis and the inventory in the FIP
[[Page 41347]]
were developed using substantially different methodologies and
assumptions, the inventories are not comparable. As a result, it cannot
be said that motor vehicle emissions are increasing from 1610 mtpy to
8,807 mtpy as ACLPI claims.38 The motor vehicle exhaust
inventory used in the FIP was based on the EPA's latest emission model
and regional estimates of emissions and, as a result, EPA believes that
it is the best inventory currently available.
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\38\ When projected 2001 emissions are estimated using the same
methodology as used in the 1991/93 plan, motor vehicle exhaust PM-10
emissions are projected to decline from 13,410 mtpy in 1989 (1991/93
Plan, p. 9-41, figure converted to mtpy from english tpy) to 8,807
mtpy in 2001 (Conformity Analysis, p. 6-3).
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Contrary to ACLPI's assertions, it is not surprising to see
decreases in tailpipe PM-10 emissions despite the increases in VMT and
the apparent lack of additional new control measures. This decline in
emissions despite the substantial increase in VMT is due primarily to
fleet turnover that brings cleaner cars into the fleet to replace
older, dirtier ones and implementation of control programs such as I/M
and clean fuel requirements. Decreasing motor vehicle emissions, in
fact, reflects the reality of almost three decades of successful
technological controls on motor vehicles.
Comment: ACLPI states that the RFP demonstration does not show
annual emission reductions--it only purports to show reductions in the
year 2001.
Response: As discussed above, EPA does not believe that annual
emission reductions are necessary to demonstrate RFP in areas
demonstrating the impracticability of attaining the PM-10 standard.
However, EPA has qualitatively shown that this FIP should result in
annual emission reductions from the 1998 promulgation until the
December 31, 2001 attainment date.
E. Indian Reservations
As discussed in EPA's proposed FIP, there are two Indian
reservations (the Salt River Pima-Maricopa Indian Community and the
Fort McDowell Mojave-Apache Indian Community) and a portion of a third
reservation (the Gila River Indian Community) in the Phoenix PM-10
nonattainment area. The FIP measures do not cover sources on these
reservations. See 63 FR 15920, 15941. EPA received comments from the
Salt River Pima-Maricopa Indian Community supporting EPA's proposal and
reiterating their willingness to work with EPA under the EPA's Tribal
Authority Rule which became effective on March 16, 1998.
V. Administrative Requirements
A. Executive Order (E.O.) 12866
Under Executive Order 12866, 58 FR 51735 (October 4, 1993), the
Agency must determine whether the regulatory action is ``significant''
and therefore subject to 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.
Due to potential novel policy issues this action is considered a
significant regulatory action and therefore must be reviewed by OMB.
Changes made in response to OMB suggestions or recommendations will be
documented in the public record.
B. Regulatory Flexibility Analysis
1. Regulatory Flexibility Act Requirements
Under the Regulatory Flexibility Act (RFA), 5 U.S.C. section 601
et. seq., EPA must prepare a regulatory flexibility analysis assessing
the impact of any proposed or final rule on small entities unless EPA
certifies that the rule will not have a significant economic impact on
a substantial number of small entities. 5 U.S.C. 603, 604 and 605(b).
Small entities include small businesses, small not-for-profit
enterprises, and government entities with jurisdiction over populations
of less than 50,000.
For the purposes of this inquiry, as it applies to the two proposed
federal measures, the fugitive dust rule and the commitment for the
development and implementation of RACM for the agricultural sector, EPA
is assuming that the affected or potentially affected sources
constitute ``small entities'' as defined by the RFA.
The final federal measures are intended to fill gaps in the Arizona
PM-10 SIP for the Phoenix nonattainment area. For non-agricultural
fugitive dust sources, while the County has adopted and EPA has
approved Rule 310 into the SIP, the County has not made a commitment to
provide adequate resources to ensure enforcement of the rule as it
applies to the unpaved road, unpaved parking lot and vacant lot source
categories.39 Further, application of Rule 310 to
agricultural sources including fields and aprons is affected by the
provision in section 102 (incorporating A.R.S. 49-504.4) that states
that the rule ``shall not be construed so as to prevent normal farm
cultural practices.'' Therefore, applicability of the rule to such
sources depends on what dust-generating operation is occurring at the
source. In other words, Rule 310 applies to some operations on
agricultural fields and aprons and not to others.
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\39\ The County typically only ensures compliance with Rule 310
for these sources on a complaint basis.
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2. RFA Analysis
a. Federal Rule for Unpaved Roads, Unpaved Parking Lots, and Vacant
Lots. The starting point for EPA's analysis is Maricopa County's Rule
310. Regardless of the County's resources for enforcing the rule with
respect to nonagricultural fugitive dust sources, those sources are
legally responsible for complying with it. Failure to do so subjects
such sources to potential enforcement action by EPA, the State, County
and/or citizens. Thus, for the purpose of analyzing whether the
proposed FIP rule will have ``a significant economic impact,'' EPA
assumes that sources subject to the rule are complying with it. The
appropriate inquiry then is whether the terms of EPA's proposed rule
would impose a significant economic impact beyond that imposed by the
terms of Rule 310.
Section 101 of Rule 310 states that the purpose of the rule is
``[t]o limit the emission of particulate matter into the ambient air
from any property, operation or activity that may serve as an open
fugitive dust source.'' Further, the provisions of the rule ``apply to
any activity, equipment, operation and/or man-made or man-caused
condition or practice * * * capable of generating fugitive dust. * *
*'' Sections 305, 306, 309 and 312 of the rule contain the regulatory
requirements applicable to the following source categories: vehicle use
in open areas and vacant parcels, unpaved parking areas, vacant areas,
and roadways. These requirements differ to some extent depending on the
source category, but generally they mandate the implementation of RACM
before certain dust-producing activities can be undertaken. RACM is
defined in section 221 as ``[a] technique, practice, or procedure used
to prevent or
[[Page 41348]]
minimize the generation, emission, entrainment, suspension and/or
airborne transport of fugitive dust.'' As further defined in subsection
221.1, and as pertinent to this analysis, RACM include, but are not
limited to: curbing, paving, applying dust suppressants, and/or
physically stabilizing with vegetation and gravel.
While subsection 211.1 does not specify which of the listed
measures are appropriate for what types of source categories, the
general definition of RACM in section 221 together with the list of
RACM measures in subsection 211.1 provide a basis for selecting
measures which are appropriate for a particular source to prevent or
minimize dust emissions, to the extent other provisions of Rule 310 do
not specify a particular RACM measure.
EPA's final fugitive dust rule is intended to establish a RACM
requirement for unpaved parking lots, unpaved roads and vacant lots
that is substantively equivalent to that established for the same
sources by the Maricopa County rule. As noted above, the requirements
of the County rule differ to some extent depending on the source
category; EPA's proposed rule mirrors those differences. The primary
difference between the County rule and EPA's final rule is that the EPA
rule provides greater specificity and detail regarding which RACM are
appropriate for a particular source category for the purpose of
preventing or minimizing fugitive dust emissions.40
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\40\ EPA believes that it is reasonable and appropriate for its
rule to be more specific and detailed than the County rule. As a
result of the State's failure to commit sufficient enforcement
resources for its rule, EPA is having to fulfill the role of primary
enforcer of the RACM requirement for the sources described above.
EPA Region 9 will be responsible for fulfilling that role, and it is
located in San Francisco. Given the greater difficulties that Region
9 will inevitably face in enforcing the RACM requirement in Arizona,
it is reasonable for EPA to design a RACM rule that ensures EPA
enforcement of the rule will be practicable. As described above, the
County rule provides a general basis for determining which RACM
should be applied to which source categories. But its lack of
specificity makes it more likely that the agency enforcing the rule
will routinely be called upon to address which RACM should be
applied to which source categories. By addressing this issue in the
FIP rule itself, EPA hopes to reduce the extent to which sources and
others may have to consult with the Agency to determine which RACM
are appropriate for a particular source or source category.
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In providing further specificity and detail, EPA's rule does not
change the nature of the RACM requirement already applicable to sources
covered by County Rule 310. The RACM required to be applied in the
final FIP rule are the very measures listed in subsection 211.1 of Rule
310. Beyond that, the RACM specified in the final rule for any
particular source category are the appropriate RACM for that source
category. What constitutes RACM for the source categories covered by
the final FIP rule is relatively straightforward in light of the
differences among the source categories, the low technology nature of
the potential RACM and other available information. EPA therefore
believes that its further specification of the RACM requirements does
not change the nature of the RACM requirements already applicable under
Maricopa County Rule 310 which is federally enforceable as an approved
element of the Arizona SIP.
The only other notable difference between the County rule and the
final FIP rule that is relevant to this analysis is paragraph (f) of
the proposed FIP rule. Rule 310 contains a recordkeeping requirement
for permitted dust-generating activities, but does not contain such a
requirement for unpermitted activities, including unpaved parking lots,
unpaved roads and vacant lots. Therefore, paragraph (f) of the proposed
FIP rule includes a requirement that owners/operators subject to the
rule maintain records demonstrating appropriate application of RACM.
EPA has determined that the recordkeeping requirements for the source
categories covered in the FIP rule will not have a significant economic
impact. In many cases, the owner/operator need only retain a purchase
receipt or contractor work order for the control(s) implemented. When
chemical stabilization is applied as a control measure, more specific
information regarding the product being used is required. However, this
information (e.g., type of product, label instructions) is readily
available from vendors or easily determined at the time of application.
EPA expects that the information the final FIP rule requires sources to
keep will be retained by source owners or operators in any event in the
normal course of business (e.g., for tax and accounting purposes).
EPA's final fugitive dust rule incorporates a number of changes
made in response to the public comments that EPA received on the FIP
proposal. Those changes are summarized and discussed in section IV.B.2.
above and in the TSD. The net result of the substantive changes is to
provide sources with greater flexibility than provided in the FIP
proposal and Rule 310. For example, the final FIP rule includes an
increase from 0.10 acre to 0.50 acre in the de minimis disturbed
surface area level for vacant lots; an increase from 150 to 250 ADT in
the exemption level for unpaved roads; a new de minimis use level for
unpaved parking lots; and the elimination of the DCP requirement for
weed abatement. As a result of these and other changes, the
requirements of the final FIP rule are effectively less stringent than
both the rule as proposed and Rule 310. Thus the costs of compliance
with the FIP rule are expected to be less than the proposed FIP rule
and Rule 310.
As the above discussion of the RACM requirements of the two rules
makes clear, even though the final FIP rule differs from Rule 310 in
that it is more specific and detailed, there should be no additional
burden on regulated sources because they are already legally required
to apply RACM under the County rule, and the RACM required by the final
FIP rule are substantively identical to that required under Rule
310.41
---------------------------------------------------------------------------
\41\ Since, by its terms, the requirements of Rule 310 are so
broad, the general effect of the greater specificity and detail is
that EPA's FIP rule, in its entirety, is somewhat narrower in scope
than the County's rule as it relates to unpaved roads, unpaved
parking lots and vacant lots. For example, section 312 of Rule 310
regulates users of unpaved roads, while EPA's rule regulates only
owners and operators; and Rule 310 does not exempt any unpaved
roads, while EPA's rule includes a low ADT exemption.
---------------------------------------------------------------------------
Moreover, EPA believes that the additional recordkeeping
requirement in the FIP rule will not have a significant economic impact
on the affected sources. As stated above, and in section V.A.7.b. of
the proposed rulemaking, the information required to be retained is
minimal and is therefore not expected to entail any appreciable
economic impact.
b. Federal Commitment for Agriculture. EPA's final measure to
control fugitive dust from agricultural fields and aprons consists of
an enforceable commitment to propose and finalize adoption of RACM for
those sources in September 1999 and April 2000, respectively. Prior to
this formal rulemaking, EPA intends to convene a stakeholder process to
develop the specific RACM that will ultimately be proposed for
adoption. As discussed in detail in section V.A.7.a. of the proposed
rulemaking, EPA intends the RACM to take the form of BMPs. During the
BMP development process, EPA will investigate a myriad of factors,
including the appropriate coverage of potential BMPs, regional climate,
soil and crop types, and growing seasons. Because this aspect of
today's action neither imposes specific regulatory requirements, nor
obligates EPA to propose requirements necessarily applicable to small
entities, it will not, by itself, have a significant economic impact on
a substantial number of small entities. When EPA proposes specific RACM
in the September 1999
[[Page 41349]]
rulemaking, it will either undertake a RFA analysis or certify the
proposed rule, as appropriate.
c. Certification. EPA has determined that it is not necessary to
prepare a regulatory flexibility analysis in connection with this final
rule. EPA has also determined that this rule will not have a
significant economic impact on a substantial number of small entities.
C. Unfunded Mandates Reform Act (UMRA)
Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), P.L.
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 the UMRA, EPA generally must prepare a written
statement, including a cost-benefit analysis, when EPA promulgates
``any general notice of proposed rulemaking that is likely to result in
promulgation of any rule that includes any Federal mandate that may
result in the expenditures by State, local, and tribal governments, in
the aggregate, or by the private sector, of $100 million or more'' in
any one year. A ``Federal mandate'' is defined, under section 101 of
UMRA, as a provision that ``would impose an enforceable duty'' upon the
private sector or State, local, or tribal governments'', with certain
exceptions not here relevant.
Under section 203 of UMRA, EPA must develop a small government
agency plan before EPA ``establish[es] any regulatory requirements that
might significantly or uniquely affect small governments'.
Under section 204 of UMRA, EPA is required to develop a process to
facilitate input by elected officers of State, local, and tribal
governments for EPA's ``regulatory proposals'' that contain significant
Federal intergovernmental mandates.
Under section 205 of UMRA, before EPA promulgates ``any rule for
which a written statement is required under [UMRA section] 202'', EPA
must identify and consider a reasonable number of regulatory
alternatives and either adopt the least costly, most cost-effective or
least burdensome alternative that achieves the objectives of the rule,
or explain why a different alternative was selected.
As explained above, while the final federal fugitive dust rule may
impose an enforceable duty on State or local governments, the resulting
expenditures by those entities are expected to be minimal. Tribal
governments are excluded from the coverage of this rule. In addition,
there will be no current enforceable duties imposed on, or expenditures
by, State, local or tribal governments or the private sector as a
result of the federal commitment regarding the agricultural sector.
Therefore, expenditures by State, local and tribal governments, in the
aggregate, or by the private sector, will be well under $100 million
per year as a result of today's federal measures. Consequently,
sections 202, 204 and 205 of UMRA do not apply to today's final action.
Therefore, EPA is not required and has not taken any actions to meet
the requirements of these sections of UMRA.
With respect to section 203 of UMRA, EPA has concluded that its
final actions include no regulatory requirements that will
significantly or uniquely affect small governments. As discussed in
detail in IV.B.2. above, EPA believes that the RACM requirements of the
final FIP rule for vacant lots, unpaved parking lots and unpaved roads
are already legally required under Maricopa County Rule 310 which is
federally enforceable as an approved element of the Arizona SIP.
Moreover, the requirements of EPA's final FIP rule, while more specific
and detailed, are substantively identical to those required under Rule
310. Therefore, there should be no additional burden on regulated
sources, including small governments. With respect to EPA's enforceable
commitment for the agricultural sector, such a commitment neither
imposes specific regulatory requirements, nor obligates EPA to propose
requirements necessarily applicable to small entities. Thus, neither
EPA's fugitive dust rule nor its commitment for the agricultural sector
will significantly or uniquely affect small governments. Consequently,
EPA has not developed a small government plan. Nevertheless, prior to
EPA's proposed action, the Agency held numerous meetings with
potentially affected representatives of the State and local governments
to discuss the requirements of, and receive input regarding, the
proposed federal fugitive dust rule and commitment for the agricultural
sector.
D. Paperwork Reduction Act
The information collection requirements in this final rule have
been submitted for approval to the Office of Management and Budget
(OMB) under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. An
Information Collection Request (ICR) document has been prepared by EPA
(ICR No. 1855.02) and a copy may be obtained from Sandy Farmer, OPPE
Regulatory Information Division; U.S. Environmental Protection Agency
(2137); 401 M St., S.W.; Washington, DC 20460 or by calling (202) 260-
2740.
EPA's final FIP rule for unpaved parking lots, unpaved roads and
vacant lots includes recordkeeping and reporting requirements which
will help ensure source compliance with the rule's control
requirements. In general, EPA believes the recordkeeping and reporting
requirements are the minimal requirements necessary to demonstrate
compliance. The requirements include:
--Owners/operators of unpaved roads must keep a record which indicates
the date and type of control (i.e., paving, stabilizing, or applying
gravel) applied to the road.
--Owners/operators of unpaved parking lots must keep a record which
indicates the date and type of control (i.e., paving, stabilizing,
applying gravel, or temporary stabilization for lots used less than 35
days per year) applied to the unpaved parking lot.
--Owners/operators of vacant lots with disturbed surfaces must keep a
record which indicates the date and type of control (i.e., applying
ground cover vegetation, stabilizing, restoring to natural undisturbed
state, or applying gravel) applied to the vacant lot.
--Owners/operators of vacant lots with motor vehicle disturbances must
keep a record which indicates the date and type of control applied to
the vacant lot.
--Agency surveys will be conducted by the EPA or other appropriate
agency to determine the effectiveness of the rule in the Phoenix area.
The estimated recordkeeping and reporting burden for the proposed
FIP rule was about 9716 hours and the estimated labor cost was about
$173,632. However, since the final FIP rule no longer requires the
submittal of dust control plans for weed abatement activity, the
estimated recordkeeping and reporting burden for the final FIP rule is
about 5297 hours and the estimated labor cost is about $93,455. No
capital/start-up costs or operational and maintenance costs are
anticipated. Burden means the total time, effort, or financial
resources expended by persons to generate, maintain, retain, or
disclose or provide information to or for a Federal agency. This
includes the time needed to review instructions; develop, acquire,
install, and utilize technology and systems for the purposes of
collecting, validating, and verifying information, processing and
maintaining information, and disclosing and providing information;
adjust the existing ways to comply with any previously applicable
instructions and
[[Page 41350]]
requirements; train personnel to be able to respond to a collection of
information; search data sources; complete and review the collection of
information; and transmit or otherwise disclose the information.
An agency may not conduct or sponsor, and a person is not required
to respond to a collection of information unless it displays a
currently valid OMB control number. The OMB control number for EPA's
regulations is listed in 40 CFR Part 9 and 48 CFR Chapter 15.
Send comments on the Agency's need for this information, the
accuracy of the provided burden estimates, and any suggested methods
for minimizing respondent burden, including through the use of
automated collection techniques, to the Director, OPPE Regulatory
Information Division; U.S. Environmental Protection Agency (2137); 401
M St., S.W.; Washington, DC 20460; and to the Office of Information and
Regulatory Affairs, Office of Management and Budget, 725 17th St., N.W.
Washington, DC 20503, marked ``Attention: Desk Officer for EPA.''
Comments are requested by September 2, 1998. Include the ICR number in
any correspondence.
E. E.O. 13045: Protection of Children From Environmental Health Risks
and Safety Risks
Executive Order 13045, entitled ``Protection of Children from
Environmental Health Risks and Safety Risks (62 FR 19885 (April 23,
1997)), applies to any rule that EPA determines (1) ``economically
significant'' as defined under E.O. 12866 and (2) the environmental
health or safety risk addressed by the rule has 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.
Today's final action promulgating a moderate area PM-10 federal
implementation plan for the Phoenix area is not subject to E.O. 13045
because it is not an economically significant regulatory action as
defined by E.O. and because it does not involve decisions on
environmental health risks or safety risks that may disproportionately
affect children.
F. Submission to Congress and the General Accounting Office
The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the
Small Business Regulatory Enforcement Fairness Act of 1996, generally
provides that before a rule may take effect, the agency promulgating
the rule must submit a rule report, which includes a copy of the rule,
to each House of the Congress and to the Comptroller General of the
United States. EPA will submit a report containing this rule and other
required information to the U.S. Senate, the U.S. House of
Representatives, and the Comptroller General of the United States prior
to publication of the rule in the Federal Register. This rule is not a
``major'' rule as defined by 5 U.S.C. 804(2).
G. Petitions for Judicial Review
Under section 307(b)(1) of the Clean Air Act, petitions for
judicial review of this action must be filed in the United States Court
of Appeals for the appropriate circuit by October 2, 1998. Filing a
petition for reconsideration by the Administrator of this final rule
does not affect the finality of this rule for the purposes of judicial
review nor does it extend the time within which a petition for judicial
review may be filed, and shall not postpone the effectiveness of such
rule or action. This action may not be challenged later in proceedings
to enforce its requirements. (See section 307(b)(2)).
List of Subjects in 40 CFR Part 52
Environmental protection, Air pollution control, Intergovernmental
relations, Particulate matter, Reporting and recordkeeping
requirements.
Dated: July 17, 1998.
Carol M. Browner,
Administrator.
For the reasons set forth in the preamble, part 52, chapter I,
title 40 of the Code of Federal Regulations is amended as follows:
PART 52--APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS
1. The authority citation for part 52 continues to read as follows:
Authority: 42 U.S.C. 7401 et seq.
Subpart D--Arizona
2. Section 52.123 is amended by adding paragraph (h) to read as
follows:
Sec. 52.123 Approval Status.
* * * * *
(h) Pursuant to the federal planning authority in section 110(c) of
the Clean Air Act, the Administrator finds that the applicable
implementation plan for the Maricopa County PM-10 nonattainment area
provides for the implementation of reasonably available control
measures as required by section 189(a)(1)(C) and demonstrates
attainment by the applicable attainment date as required and allowed by
sections 172(c)(2) and 189(a)(1)(B).
3. Section 52.124 is amended by adding paragraph (c) to read as
follows:
Sec. 52.124 Part D disapproval.
* * * * *
(c) The Administrator disapproves the attainment demonstration for
the annual PM-10 national ambient air quality standard and the
provisions for implementation of reasonably available control measures
for the annual PM-10 national ambient air quality standard in the MAG
1991 Particulate Plan for PM-10 for the Maricopa County Area and 1993
Revisions (July 1993) submitted by the Arizona Department of
Environmental Quality on August 11, 1993 as revised by the submittal of
a Revised Chapter 9 on March 3, 1994 because they do not meet the
requirements of sections 189(a)(1)(B) and 189(a)(1)(C) of Part D of
title I of the Clean Air Act.
4. Subpart D is amended by adding Secs. 52.127 and 52.128 to read
as follows:
Sec. 52.127 Commitment to promulgate and implement reasonably
available control measures for the agricultural fields and aprons.
The Administrator shall promulgate and implement reasonably
available control measures (RACM) pursuant to section 189(a)(1)(C) of
the Clean Air Act for agricultural fields and aprons in the Maricopa
County (Phoenix) PM-10 nonattainment area according to the following
schedule: by no later than September, 1999, the Administrator shall
sign a Notice of Proposed Rulemaking; by no later than April, 2000, the
Administrator shall sign a Notice of Final Rulemaking; and by no later
than June, 2000, EPA shall begin implementing the final RACM.
Sec. 52.128 Rule for unpaved parking lots, unpaved roads and vacant
lots.
(a) General. (1) Purpose. The purpose of this section is to limit
the emissions of particulate matter into the ambient air from human
activity on unpaved parking lots, unpaved roads and vacant lots.
(2) Applicability. The provisions of this section shall apply to
owners/operators of unpaved roads, unpaved parking lots and vacant lots
and responsible parties for weed abatement on vacant lots in the
Phoenix PM-10 nonattainment area. This section does not apply to
unpaved roads, unpaved parking lots or vacant lots located on an
industrial facility, construction, or earth-moving site that has an
approved
[[Page 41351]]
permit issued by Maricopa County Environmental Services Division under
Rule 200, Section 305, Rule 210 or Rule 220 containing a Dust Control
Plan approved under Rule 310 covering all unpaved parking lots, unpaved
roads and vacant lots. This section does not apply to the two Indian
Reservations (the Salt River Pima-Maricopa Indian Community and the
Fort McDowell Mojave-Apache Indian Community) and a portion of a third
reservation (the Gila River Indian Community) in the Phoenix PM-10
nonattainment area. Nothing in this definition shall preclude
applicability of this section to vacant lots with disturbed surface
areas due to construction, earth-moving, weed abatement or other dust
generating operations which have been terminated for over eight months.
(3) The test methods described in Appendix A of this section shall
be used when testing is necessary to determine whether a surface has
been stabilized as defined in paragraph (b)(16) of this section.
(b) Definitions. (1) Average daily trips (ADT)--the average number
of vehicles that cross a given surface during a specified 24-hour time
period as determined by the Institute of Transportation Engineers Trip
Generation Report (6th edition, 1997) or tube counts.
(2) Chemical/organic stabilizer--Any non-toxic chemical or organic
dust suppressant other than water which meets any specifications,
criteria, or tests required by any federal, state, or local water
agency and is not prohibited for use by any applicable law, rule or
regulation.
(3) Disturbed surface area--Any portion of the earth's surface, or
materials placed thereon, which has been physically moved, uncovered,
destabilized, or otherwise modified from its undisturbed natural
condition, thereby increasing the potential for emission of fugitive
dust.
(4) Dust suppressants--Water, hygroscopic materials, solution of
water and chemical surfactant, foam, or non-toxic chemical/ organic
stabilizers not prohibited for use by any applicable law, rule or
regulation, as a treatment material to reduce fugitive dust emissions.
(5) EPA--United States Environmental Protection Agency, Region IX,
75 Hawthorne Street, San Francisco, California 94105.
(6) Fugitive dust--the particulate matter entrained in the ambient
air which is caused from man-made and natural activities such as, but
not limited to, movement of soil, vehicles, equipment, blasting, and
wind. This excludes particulate matter emitted directly from the
exhaust of motor vehicles and other internal combustion engines, from
portable brazing, soldering, or welding equipment, and from
piledrivers.
(7) Lot--A parcel of land identified on a final or parcel map
recorded in the office of the Maricopa County recorder with a separate
and distinct number or letter.
(8) Low use unpaved parking lot--A lot on which vehicles are parked
no more than thirty-five (35) days a year, excluding days where the
exemption in paragraph (c)(2) of this section applies.
(9) Motor vehicle--A self-propelled vehicle for use on the public
roads and highways of the State of Arizona and required to be
registered under the Arizona State Uniform Motor Vehicle Act, including
any non-motorized attachments, such as, but not limited to, trailers or
other conveyances which are connected to or propelled by the actual
motorized portion of the vehicle.
(10) Off-road motor vehicle--any wheeled vehicle which is used off
paved roadways and includes but is not limited to the following:
(i) Any motor cycle or motor-driven cycle;
(ii) Any motor vehicle commonly referred to as a sand buggy, dune
buggy, or all terrain vehicle.
(11) Owner/operator--any person who owns, leases, operates,
controls, maintains or supervises a fugitive dust source subject to the
requirements of this section.
(12) Paving--Applying asphalt, recycled asphalt, concrete, or
asphaltic concrete to a roadway surface.
(13) Phoenix PM-10 nonattainment area--such area as defined in 40
CFR 81.303, excluding Apache Junction.
(14) PM-10--Particulate matter with an aerodynamic diameter less
than or equal to a nominal 10 micrometers as measured by reference or
equivalent methods that meet the requirements specified for PM-10 in 40
CFR Part 50, Appendix J.
(15) Reasonably available control measures (RACM)--Techniques used
to prevent the emission and/or airborne transport of fugitive dust and
dirt.
(16) Stabilized surface--(i) Any unpaved road or unpaved parking
lot surface in which any fugitive dust plume emanating from vehicular
movement does not exceed 20 percent opacity as determined in section I.
of Appendix A of this section.
(ii) Any vacant lot surface with:
(A) A visible crust which is greater than 0.6 centimeters (cm)
thick and is not easily crumbled between the fingers as determined in
section II.1. of Appendix A of this section;
(B) A threshold friction velocity (TFV), corrected for non-erodible
elements, of 100 cm/second or higher as determined in section II.2 of
Appendix A of this section;
(C) Flat vegetation cover equal to at least 50 percent as
determined in section II. 3. of Appendix A of this section;
(D) Standing vegetation cover equal to or greater than 30 percent
as determined in section II. 4. of Appendix A of this section; or
(E) Standing vegetation cover equal to or greater than 10 percent
as determined in section II.4. of Appendix A of this section where
threshold friction velocity, corrected for non-erodible elements, as
determined in section II. 2 of Appendix A of this section is equal to
or greater than 43 cm/second.
(17) Unpaved Parking Lot--A privately or publicly owned or operated
area utilized for parking vehicles that is not paved and is not a Low
Use Unpaved Parking Lot.
(18) Unpaved Road--Any road, equipment path, or driveway that is
not paved which is open to public access and owned/operated by any
federal, state, county, municipal or other governmental or quasi-
governmental agencies.
(19) Urban or Suburban Open Area--An unsubdivided or undeveloped
tract of land adjoining a residential, industrial or commercial area,
located on public or private property.
(20) Vacant Lot--A subdivided residential, industrial,
institutional, governmental or commercial lot which contains no
approved or permitted buildings or structures of a temporary or
permanent nature.
(c) Exemptions. The following requirements in paragraph (d) of this
section do not apply:
(1) In paragraphs (d)(1) and (d)(3)(iii) of this section: Any
unpaved parking lot or vacant lot 5,000 square feet or less.
(2) In paragraph (d)(1) of this section: Any unpaved parking lot on
any day in which ten (10) or fewer vehicles enter.
(3) In paragraphs (d)(3)(i) and (d)(3)(ii) of this section: Any
vacant lot with less than 0.50 acre (21,780 square feet) of disturbed
surface area(s).
(4) In paragraph (d) of this section: Non-routine or emergency
maintenance of flood control channels and water retention basins.
(5) In paragraph (d) of this section: Vehicle test and development
facilities and operations when dust is required to test and validate
design integrity, product quality and/or commercial acceptance. Such
facilities and
[[Page 41352]]
operations shall be exempted from the provisions of this section only
if such testing is not feasible within enclosed facilities.
(6) In paragraph (d)(3)(i) of this section: Weed abatement
operations performed on any vacant lot or property under the order of a
governing agency for the control of a potential fire hazard or
otherwise unhealthy condition provided that mowing, cutting, or another
similar process is used to maintain weed stubble at least three (3)
inches above the soil surface. This includes the application of
herbicides provided that the clean-up of any debris does not disturb
the soil surface.
(7) In paragraph (d)(3)(i) of this section: Weed abatement
operations that receive an approved Earth Moving permit under Maricopa
County Rule 200, Section 305 (adopted 11/15/93).
(d) Requirements. (1) Unpaved parking lots.
(i) Any owners/operators of an unpaved parking lot shall implement
one of the following RACM on any surface area(s) of the lot on which
vehicles enter and park.
(A) Pave; or
(B) Apply chemical/organic stabilizers in sufficient concentration
and frequency to maintain a stabilized surface; or
(C) Apply and maintain surface gravel uniformly such that the
surface is stabilized.
(ii) Any owners/operators of a Low Use Unpaved Parking Lot as
defined in paragraph (b)(8) of this section shall implement one of the
RACM under paragraph (d)(1)(i) of this section on any day(s) in which
over 100 vehicles enter the lot, such that the surface area(s) on which
vehicles enter and park is/are stabilized throughout the duration of
time that vehicles are parked.
(2) Unpaved roads. Any owners/operators of existing unpaved roads
with ADT volumes of 250 vehicles or greater shall implement one of the
following RACM along the entire surface of the road or road segment
that is located within the Phoenix non-attainment area by June 10,
2000:
(i) Pave; or
(ii) Apply chemical/organic stabilizers in sufficient concentration
and frequency to maintain a stabilized surface; or
(iii) Apply and maintain surface gravel uniformly such that the
surface is stabilized.
(3) Vacant lots. The following provisions shall be implemented as
applicable.
(i) Weed abatement. No person shall remove vegetation from any
vacant lot by blading, disking, plowing under or any other means
without implementing all of the following RACM to prevent or minimize
fugitive dust.
(A) Apply a dust suppressant(s) to the total surface area subject
to disturbance immediately prior to or during the weed abatement.
(B) Prevent or eliminate material track-out onto paved surfaces and
access points adjoining paved surfaces.
(C) Apply a dust suppressant(s), gravel, compaction or alternative
control measure immediately following weed abatement to the entire
disturbed surface area such that the surface is stabilized.
(ii) Disturbed surfaces. Any owners/operators of an urban or
suburban open area vacant lot of which any portion has a disturbed
surface area(s) that remain(s) unoccupied, unused, vacant or
undeveloped for more than fifteen (15) calendar days shall implement
one of the following RACM within sixty (60) calendar days following the
disturbance.
(A) Establish ground cover vegetation on all disturbed surface
areas in sufficient quantity to maintain a stabilized surface; or
(B) Apply a dust suppressant(s) to all disturbed surface areas in
sufficient quantity and frequency to maintain a stabilized surface; or
(C) Restore to a natural state, i.e. as existing in or produced by
nature without cultivation or artificial influence, such that all
disturbed surface areas are stabilized; or
(D) Apply and maintain surface gravel uniformly such that all
disturbed surface areas are stabilized.
(iii) Motor vehicle disturbances. Any owners/operators of an urban
or suburban open area vacant lot of which any portion has a disturbed
surface area due to motor vehicle or off-road motor vehicle use or
parking, notwithstanding weed abatement operations or use or parking by
the owner(s), shall implement one of the following RACM within 60
calendar days following the initial determination of disturbance.
(A) Prevent motor vehicle and off-road motor vehicle trespass/
parking by applying fencing, shrubs, trees, barriers or other effective
measures; or
(B) Apply and maintain surface gravel or chemical/organic
stabilizer uniformly such that all disturbed surface areas are
stabilized.
(4) Alternative control measures. For sources subject to
requirements in paragraphs (d)(1), (d)(2), (d)(3)(ii) and (d)(3)(iii)
of this section: As an alternative to compliance, owners/operators may
use any other alternative control measures approved by EPA pursuant to
paragraphs (e)(1) and (e)(2) of this section as equivalent to the
methods specified in paragraph (d) of this section.
(5) Implementation date of RACM. All of the requirements in
paragraph (d) of this section shall be effective eight (8) months from
September 2, 1998. For requirements in paragraph (d)(3)(ii) and
(d)(3)(iii) of this section, RACM shall be implemented within eight (8)
months from September 2, 1998, or within 60 calendar days following the
disturbance, whichever is later.
(e) Administrative requirements. (1) Proposed alternative control
measures for sources subject to paragraph (d)(2) of this section must
be submitted to EPA for approval within one year from September 2,
1998. Proposed alternative control measures for sources subject to
paragraph (d)(1) of this section must be submitted to EPA for approval
within 90 calendar days prior to the required RACM implementation date
as specified in this section. Proposed alternative control measures for
sources subject to paragraphs (d)(3)(ii) and (d)(3)(iii) of this
section must be submitted to EPA for approval within 90 calendar days
prior to the required RACM implementation date as specified in this
section or within 60 calendar days following the initial determination
of disturbance, whichever is later.
(2) Upon receipt of an alternative control measure, EPA shall
provide written notice within 30 calendar days to the owner/operator
approving or disapproving the alternative control measure. Should EPA
not provide written notice of approval or disapproval within the above
deadline, the owner/operator shall assume that the alternative control
measure is approved. Upon receiving notice of EPA approval, the owner/
operator shall implement the alternative control measure according to
the timeframe established in this section unless otherwise specified by
EPA. Upon receiving notice of EPA disapproval of the alternative
control measure, the owner/operator shall implement RACM according to
the specifications and timeframe established in this section. For
sources submitting an alternative control measure under paragraphs
(d)(3)(ii) or (d)(3)(iii) of this section, owners/operators shall
implement the alternative control measure if approved by EPA within 60
calendar days upon receiving written notice, or, upon disapproval of
the alternative control measure, implement RACM as specified in this
section within 60 calendar days upon receiving written notice.
(f) Monitoring and records. (1) Any owners/operators that are
subject to the provisions of this section shall compile and retain
records that provide evidence
[[Page 41353]]
of control measure application, indicating the type of treatment or
measure, extent of coverage and date applied. For control measures
involving chemical/organic stabilization, records shall also indicate
the type of product applied, vendor name, label instructions for
approved usage, and the method, frequency, concentration and quantity
of application.
(2) Copies of control measure records and dust control plans along
with supporting documentation shall be retained for at least three
years.
(3) Agency surveys. (i) EPA or other appropriate entity shall
conduct a survey of the number and size (or length) of unpaved roads,
unpaved parking lots, and vacant lots subject to the provisions of this
rule located within the Phoenix PM-10 nonattainment area beginning no
later than 365 days from September 2, 1998.
(ii) EPA or other appropriate entity shall conduct a survey at
least every three years within the Phoenix PM-10 nonattainment area
beginning no later than 365 days from September 2, 1998, which
includes:
(A) An estimate of the percentage of unpaved roads, unpaved parking
lots, and vacant lots subject to this rule to which RACM as required in
this section have been applied; and
(B) A description of the most frequently applied RACM and estimates
of their control effectiveness.
Appendix A to Sec. 52.128 Test Methods To Determine Whether a Surface
Is Stabilized
I. Unpaved Roads and Unpaved Parking Lots
Conduct opacity observations in accordance with Reference Method
9 (40 CFR Part 60, appendix A) and Methods 203A and 203C of this
appendix, with opacity readings taken at five second observation
intervals and two consecutive readings per plume beginning with the
first reading at zero seconds, in accordance with Method 203C,
sections 2.3.2. and 2.4.2 of this appendix. Conduct visible opacity
tests only on dry unpaved surfaces (i.e. when the surface is not
damp to the touch) and on days when average wind speeds do not
exceed 15 miles per hour (mph).
Method 203A--Visual Determination of Opacity of Emissions From
Stationary Sources for Time-Arranged Regulations
Method 203A is virtually identical to EPA's Method 9 of 40 CFR
part 60, appendix A except for the data-reduction procedures, which
provide for averaging times other than 6 minutes. That is, using
Method 203A with a 6-minute averaging time would be the same as
following EPA Method 9. Additionally, Method 203A provides
procedures for fugitive dust applications. The certification
procedures provided in section 3 are virtually identical to Method 9
and are provided here, in full, for clarity and convenience.
1. Applicability and Principle
1.1 Applicability. This method is applicable for the
determination of the opacity of emissions from sources of visible
emissions for time-averaged regulations. A time-averaged regulation
is any regulation that requires averaging visible emission data to
determine the opacity of visible emissions over a specific time
period.
1.2 Principle. The opacity of emissions from sources of visible
emissions is determined visually by an observer qualified according
to the procedures of section 3.
2. Procedures
An observer qualified in accordance with section 3 of this
method shall use the following procedures for visually determining
the opacity of emissions.
2.1 Procedures for Emissions from Stationary Sources. These
procedures are not applicable to this section.
2.2 Procedures for Fugitive Process Dust Emissions. These
procedures are applicable for the determination of the opacity of
fugitive emissions by a qualified observer. The qualified field
observer should do the following:
2.2.1 Position. Stand at a position at least 5 meters from the
fugitive dust source in order to provide a clear view of the
emissions with the sun oriented in the 140-degree sector to the
back. Consistent as much as possible with maintaining the above
requirements, make opacity observations from a position such that
the line of vision is approximately perpendicular to the plume and
wind direction. As much as possible, if multiple plumes are
involved, do not include more than one plume in the line of sight at
one time.
2.2.2 Field Records. Record the name of the plant or site,
fugitive source location, source type [pile, stack industrial
process unit, incinerator, open burning operation activity, material
handling (transfer, loading, sorting, etc.)], method of control
used, if any, observer's name, certification data and affiliation,
and a sketch of the observer's position relative to the fugitive
source. Also, record the time, estimated distance to the fugitive
source location, approximate wind direction, estimated wind speed,
description of the sky condition (presence and color of clouds),
observer's position relative to the fugitive source, and color of
the plume and type of background on the visible emission observation
form when opacity readings are initiated and completed.
2.2.3 Observations. Make opacity observations, to the extent
possible, using a contrasting background that is perpendicular to
the line of vision. For roads, storage piles, and parking lots, make
opacity observations approximately 1 meter above the surface from
which the plume is generated. For other fugitive sources, make
opacity observations at the point of greatest opacity in that
portion of the plume where condensed water vapor is not present. For
intermittent sources, the initial observation should begin
immediately after a plume has been created above the surface
involved. Do not look continuously at the plume but, instead,
observe the plume momentarily at 15-second intervals.
2.3 Recording Observations. Record the opacity observations to
the nearest 5 percent every 15 seconds on an observational record
sheet. Each momentary observation recorded represents the average
opacity of emissions for a 15-second period.
2.4 Data Reduction for Time-Averaged Regulations. A set of
observations is composed of an appropriate number of consecutive
observations determined by the averaging time specified. Divide the
recorded observations into sets of appropriate time lengths for the
specified averaging time. Sets must consist of consecutive
observations; however, observations immediately preceding and
following interrupted observations shall be deemed consecutive. Sets
need not be consecutive in time and in no case shall two sets
overlap, resulting in multiple violations. For each set of
observations, calculate the appropriate average opacity.
3. Qualification and Testing
3.1 Certification Requirements. To receive certification as a
qualified observer, a candidate must be tested and demonstrate the
ability to assign opacity readings in 5 percent increments to 25
different black plumes and 25 different white plumes, with an error
not to exceed 15 percent opacity on any one reading and an average
error not to exceed 7.5 percent opacity in each category. Candidates
shall be tested according to the procedures described in paragraph
3.2. Any smoke generator used pursuant to paragraph 3.2 shall be
equipped with a smoke meter which meets the requirements of
paragraph 3.3. Certification tests that do not meet the requirements
of paragraphs 3.2 and 3.3 are not valid.
The certification shall be valid for a period of 6 months, and
after each 6-month period, the qualification procedures must be
repeated by an observer in order to retain certification.
3.2 Certification Procedure. The certification test consists of
showing the candidate a complete run of 50 plumes, 25 black plumes
and 25 white plumes, generated by a smoke generator. Plumes shall be
presented in random order within each set of 25 black and 25 white
plumes. The candidate assigns an opacity value to each plume and
records the observation on a suitable form. At the completion of
each run of 50 readings, the score of the candidate is determined.
If a candidate fails to qualify, the complete run of 50 readings
must be repeated in any retest. The smoke test may be administered
as part of a smoke school or training program, and may be preceded
by training or familiarization runs of the smoke generator during
which candidates are shown black and white plumes of known opacity.
3.3 Smoke Generator Specifications. Any smoke generator used
for the purpose of paragraph 3.2 shall be equipped with a smoke
meter installed to measure opacity across the diameter of the smoke
generator stack. The smoke meter output shall display in-stack
opacity, based upon a path length equal to the stack exit diameter
on a full 0 to 100 percent chart recorder scale. The smoke meter
optical design and performance shall meet the specifications shown
in Table A of method 203C. The smoke meter shall be calibrated as
prescribed in paragraph 3.3.1 prior to conducting each smoke reading
test.
[[Page 41354]]
At the completion of each test, the zero and span drift shall be
checked, and if the drift exceeds 1 percent opacity, the
condition shall be corrected prior to conducting any subsequent test
runs. The smoke meter shall be demonstrated at the time of
installation to meet the specifications listed in Table A of method
203C. This demonstration shall be repeated following any subsequent
repair or replacement of the photocell or associated electronic
circuitry including the chart recorder or output meter, or every 6
months, whichever occurs first.
3.3.1 Calibration. The smoke meter is calibrated after allowing
a minimum of 30 minutes warm-up by alternately producing simulated
opacity of 0 percent and 100 percent. When stable response at 0
percent or 100 percent is noted, the smoke meter is adjusted to
produce an output of 0 percent or 100 percent, as appropriate. This
calibration shall be repeated until stable 0 percent and 100 percent
readings are produced without adjustment. Simulated 0 percent and
100 percent opacity values may be produced by alternately switching
the power to the light source on and off while the smoke generator
is not producing smoke.
3.3.2 Smoke Meter Evaluation. The smoke meter design and
performance are to be evaluated as follows:
3.3.2.1 Light Source. Verify from manufacturer's data and from
voltage measurements made at the lamp, as installed, that the lamp
is operated within 5 percent of the nominal rated
voltage.
3.3.2.2 Spectral Response of Photocell. Verify from
manufacturer's data that the photocell has a photopic response;
i.e., the spectral sensitivity of the cell shall closely approximate
the standard spectral-luminosity curve for photopic vision which is
referenced in (b) of Table A of method 203C.
3.3.2.3 Angle of View. Check construction geometry to ensure
that the total angle of view of the smoke plume, as seen by the
photocell, does not exceed 15 degrees. Calculate the total angle of
view as follows:
xv = 2 tan-1 d/2L,
Where:
v = total angle of view;
d = the photocell diameter + the diameter of the limiting aperture;
and
L = distance from the photocell to the limiting aperture.
The limiting aperture is the point in the path between the
photocell and the smoke plume where the angle of view is most
restricted. In smoke generator smoke meters, this is normally an
orifice plate.
3.3.2.4 Angle of Projection. Check construction geometry to
ensure that the total angle of projection of the lamp on the smoke
plume does not exceed 15 degrees. Calculate the total angle of
projection as follows:
p = 2 tan-1 d/2L
Where:
p = total angle of projection;
d = the sum of the length of the lamp filament + the diameter of the
limiting aperture; and
L = the distance from the lamp to the limiting aperture.
3.3.2.5 Calibration Error. Using neutral-density filters of
known opacity, check the error between the actual response and the
theoretical linear response of the smoke meter. This check is
accomplished by first calibrating the smoke meter according to 3.3.1
and then inserting a series of three neutral-density filters of
nominal opacity of 20, 50, and 75 percent in the smoke meter path
length. Use filters calibrated within 2 percent. Care
should be taken when inserting the filters to prevent stray light
from affecting the meter. Make a total of five nonconsecutive
readings for each filter. The maximum opacity error on any one
reading shall be 3 percent.
3.3.2.6 Zero and Span Drift. Determine the zero and span drift
by calibrating and operating the smoke generator in a normal manner
over a 1-hour period. The drift is measured by checking the zero and
span at the end of this period.
3.3.2.7 Response Time. Determine the response time by producing
the series of five simulated 0 percent and 100 percent opacity
values and observing the time required to reach stable response.
Opacity values of 0 percent and 100 percent may be simulated by
alternately switching the power to the light source off and on while
the smoke generator is not operating.
4. References
1. U. S. Environmental Protection Agency. Standards of Performance
for New Stationary Sources; appendix A; Method 9 for Visual
Determination of the Opacity of Emissions from Stationary Sources.
Final Rule. 39 FR 219. Washington, DC. U. S. Government Printing
Office. November 12, 1974.
2. Office of Air and Radiation. ``Quality Assurance Guideline for
Visible Emission Training Programs.'' EPA-600/S4-83-011. Quality
Assurance Division. Research Triangle Park, N.C. May 1982.
3. ``Method 9--Visible Determination of the Opacity of Emissions
from Stationary Sources.'' February 1984. Quality Assurance Handbook
for Air Pollution Measurement Systems. Volume III, section 3.1.2.
Stationary Source Specific Methods. EPA-600-4-77-027b. August 1977.
Office of Research and Development Publications, 26 West Clair
Street, Cincinnati, OH.
4. Office of Air Quality Planning and Standards. ``Opacity Error for
Averaging and Nonaveraging Data Reduction and Reporting
Techniques.'' Final Report-SR-1-6-85. Emission Measurement Branch,
Research Triangle Park, N.C. June 1985.
5. The U. S. Environmental Protection Agency. Preparation, Adoption,
and Submittal of State Implementation Plans. Methods for Measurement
of PM10 Emissions from Stationary Sources. Final Rule.
Federal Register. Washington, DC. U. S. Government Printing Office.
Volumes 55. No. 74. pps. 14246-14279. April 17, 1990.
Method 203C--Visual Determination of Opacity of Emissions From
Stationary Sources for Instantaneous Limitation Regulations
Method 203C is virtually identical to EPA's Method 9 of appendix
A to 40 CFR part 60, except for the data-reduction procedures which
have been modified for application to instantaneous limitation
regulations. Additionally, Method 203C provides procedures for
fugitive dust applications which were unavailable when Method 9 was
promulgated. The certification procedures in section 3 are identical
to Method 9. These certification procedures are provided in Method
203A as well, and, therefore, have not been repeated in this method.
1. Applicability and Principle
1.1 Applicability. This method is applicable for the
determination of the opacity of emissions from sources of visible
emissions for instantaneous limitations. An instantaneous limitation
regulation is an opacity limit which is never to be exceeded.
1.2 Principle. The opacity of emissions from sources of visible
emissions is determined visually by a qualified observer.
2. Procedures
The observer qualified in accordance with section 3 of this
method shall use the following procedures for visually determining
the opacity of emissions.
2.1 Procedures for Emissions From Stationary Sources. Same as
2.1, Method 203A.
2.1.1 Position. Same as 2.1.1, Method 203A.
2.1.2 Field Records. Same as 2.1.2, Method 203A.
2.1.3 Observations. Make opacity observations at the point of
greatest opacity in that portion of the plume where condensed water
vapor is not present.
Do not look continuously at the plume. Instead, observe the plume
momentarily at the interval specified in the subject regulation. Unless
otherwise specified, a 15-second observation interval is assumed.
2.1.3.1 Attached Steam Plumes. Same as 2.1.3.1, Method 203A.
2.1.3.2 Detached Steam Plumes. Same as 2.1.3.2, Method 203A.
2.2 Procedures for Fugitive Process Dust Emissions.
2.2.1 Position. Same as section 2.2.1, Method 203A.
2.2.2 Field Records. Same as section 2.2.2, Method 203A.
2.2.3 Observations.
2.2.3.1 Observations for a 15-second Observation Interval
Regulations. Same as section 2.2.3, Method 203A.
2.2.3.2 Observations for a 5-second Observation Interval
Regulations. Same as section 2.2.3, Method 203A, except, observe the
plume momentarily at 5-second intervals.
2.3 Recording Observations. Record opacity observations to the
nearest 5 percent at the prescribed interval on an observational
record sheet. Each momentary observation recorded represents the
average of emissions for the prescribed period. If a 5-second
observation period is not specified in the applicable regulation, a
15-second interval is assumed. The overall time for which recordings
are made shall be of a length appropriate to the regulation for
which opacity is being measured.
2.3.1 Recording Observations for 15-second Observation Interval
Regulations.
[[Page 41355]]
Record opacity observations to the nearest 5 percent at 15-second
intervals on an observational record sheet. Each momentary
observation recorded represents the average of emissions for a 15-
second period.
2.3.2 Recording Observations for 5-second Observation Interval
Regulations. Record opacity observations to the nearest 5 percent at
5-second intervals on an observational record sheet. Each momentary
observation recorded represents the average of emissions for 5-
second period.
2.4 Data Reduction for Instantaneous Limitation Regulations.
For an instantaneous limitation regulation, a 1-minute averaging
time will be used. Divide the observations recorded on the record
sheet into sets of consecutive observations. A set is composed of
the consecutive observations made in 1 minute. Sets need not be
consecutive in time, and in no case shall two sets overlap. Reduce
opacity observations by dividing the sum of all observations
recorded in a set by the number of observations recorded in each
set.
2.4.1 Data Reduction for 15-second Observation Intervals.
Reduce opacity observations by averaging four consecutive
observations recorded at 15-second intervals. Divide the
observations recorded on the record sheet into sets of four
consecutive observations. For each set of four observations,
calculate the average by summing the opacity of the four
observations and dividing this sum by four.
2.4.2 Data Reduction for 5-second Observation Intervals. Reduce
opacity observations by averaging 12 consecutive observations
recorded at 5-second intervals. Divide the observations recorded on
the record sheet into sets of 12 consecutive observations. For each
set of 12 observations, calculate the average by summing the opacity
of the 12 observations and dividing this sum by 12.
3. Qualification and Test
Same as section 3, Method 203A.
Table A.--Smoke Meter Design and Performance Specifications
------------------------------------------------------------------------
Parameter Specification
------------------------------------------------------------------------
a. Light Source........................... Incandescent lamp operated
at nominal rated voltage.
b. Spectral response of photocell......... Photopic (daylight spectral
response of the human eye--
Reference 4.1 of section
4.).
c. Angle of view.......................... 15 degrees maximum total
angle.
d. Angle of projection.................... 15 degrees maximum total
angle.
e. Calibration error...................... +3-percent
opacity, maximum.
f. Zero and span drift.................... 1-percent
opacity, 30 minutes.
g. Response time.......................... 5 seconds.
------------------------------------------------------------------------
II. Vacant Lots
The following test methods shall be used for determining whether
a vacant lot, or portion thereof, has a stabilized surface. Should a
disturbed vacant lot contain more than one type of disturbance,
soil, vegetation or other characteristics which are visibly
distinguishable, test each representative surface for stability
separately in random areas according to the test methods in section
II. of this appendix and include or eliminate it from the total size
assessment of disturbed surface area(s) depending upon test method
results. A vacant lot surface shall be considered stabilized if any
of the test methods in section II. of this appendix indicate that
the surface is stabilized such that the conditions defined in
paragraph (b)(16)(ii) of this section are met:
1. Determination of visible crust thickness
Where a visible crust exists, break off a small piece of crust.
Check whether it crumbles easily between the fingers. Using a ruler,
measure the thickness of the crust. Determination of thickness shall
be based on at least three (3) crustal measurements representative
of the disturbed surface area. If thin deposits of loose uncombined
grains cover more than 50 percent of a crusted surface, apply the
test method in section II.2. of this appendix to the loose material
to determine whether the surface is stabilized.
2. Determination of Threshold Friction Velocity (TFV)
For disturbed surface areas that are not crusted or vegetated,
determine threshold friction velocity (TFV) according to the
following sieving field procedure (based on a 1952 laboratory
procedure published by W. S. Chepil).
(i) Obtain and stack a set of sieves with the following
openings: 4 millimeters (mm), 2 mm, 1 mm, 0.5 mm, and 0.25 mm. Place
the sieves in order according to size openings beginning with the
largest size opening at the top. Place a collector pan underneath
the bottom (0.25 mm) sieve. Collect a sample of loose surface
material from an area at least 30 cm by 30 cm in size to a depth of
approximately 1 cm using a brush and dustpan or other similar
device. Only collect soil samples from dry surfaces (i.e. when the
surface is not damp to the touch). Remove any rocks larger than 1 cm
in diameter from the sample. Pour the sample into the top sieve (4
mm opening) and cover the sieve/collector pan unit with a lid.
Minimize escape of particles into the air when transferring surface
soil into the sieve/collector pan unit. Move the covered sieve/
collector pan unit by hand using a broad, circular arm motion in the
horizontal plane. Complete twenty circular arm movements, ten
clockwise and ten counterclockwise, at a speed just necessary to
achieve some relative horizontal motion between the sieves and the
particles. Remove the lid from the sieve/collector pan unit and
disassemble each sieve separately beginning with the largest sieve.
As each sieve is removed, examine it for loose particles. If loose
particles have not been sifted to the finest sieve through which
they can pass, reassemble and cover the sieve/collector pan unit and
gently rotate it an additional ten times. After disassembling the
sieve/collector pan unit, slightly tilt and gently tap each sieve
and the collector pan so that material aligns along one side. In
doing so, minimize escape of particles into the air. Line up the
sieves and collector pan in a row and visibly inspect the relative
quantities of catch in order to determine which sieve (or whether
the collector pan) contains the greatest volume of material. If a
visual determination of relative volumes of catch among sieves is
difficult, use a graduated cylinder to measure the volume. Estimate
TFV for the sieve catch with the greatest volume using Table 1,
which provides a correlation between sieve opening size and TFV.
Table 1.--(Metric Units). Determination of Threshold Friction Velocity
(TFV)
------------------------------------------------------------------------
Opening TFV (cm/
Tyler Sieve No. (mm) s)
------------------------------------------------------------------------
5................................................ 4 10%............................. 5
5% and < 10%.................... 3
< 5% and 1%..................... 2
< 1%........................................ None.
------------------------------------------------------------------------
3. Determination of Flat Vegetation Cover
Flat vegetation includes attached (rooted) vegetation or
unattached vegetative debris lying on the surface with a predominant
horizontal orientation that is not subject to movement by wind. Flat
vegetation which is dead but firmly attached shall be considered
equally protective as live vegetation. Stones or other aggregate
larger than one centimeter in diameter shall be considered
protective cover in the course of conducting the line transect
method. Where flat vegetation exists, conduct the following line
transect method.
(i) Stretch a one-hundred (100) foot measuring tape across a
disturbed surface area. Firmly anchor both ends of the measuring
tape into the surface using a tool such as a screwdriver with the
tape stretched taut and close to the soil surface. If vegetation
exists in regular rows, place the tape diagonally (at approximately
a 45 degree angle) away from a parallel or perpendicular position to
the vegetated rows. Pinpoint an area the size of a \3/32\ inch
diameter brazing rod or wooden dowel centered above each one-foot
interval mark along one edge of the tape. Count the number of times
that flat vegetation lies directly underneath the pinpointed area at
one-foot intervals. Consistently observe the underlying surface from
a 90 degree angle directly above each pinpoint on one side of the
tape. Do not count the underlying surface as vegetated if any
portion of the pinpoint extends beyond the edge of the vegetation
underneath in any direction. If clumps of vegetation or vegetative
debris lie underneath the pinpointed area, count the surface as
vegetated unless bare soil is visible directly below the pinpointed
area. When 100 observations have been made, add together the number
of times a surface was counted as vegetated. This total represents
the percent of flat vegetation cover (e.g. if 35 positive counts
were made, then vegetation cover is 35 percent). If the disturbed
surface area is too small for 100 observations, make as many
observations as possible. Then multiply the count of vegetated
surface areas by the appropriate conversion factor to obtain percent
cover. For example, if vegetation was counted 20 times within a
total of 50 observations, divide 20 by 50 and multiply by 100 to
obtain a flat vegetation cover of 40 percent.
(ii) Conduct the above line transect test method an additional
two (2) times on areas representative of the disturbed surface and
average results.
4. Determination of Standing Vegetation Cover
Standing vegetation includes vegetation that is attached
(rooted) with a predominant vertical orientation. Standing
vegetation which is dead but firmly rooted shall be considered
equally protective as live vegetation. Conduct the following
standing vegetation test method to determine if 30 percent cover or
more exists. If the resulting percent cover is less than 30 percent
but equal to or greater than 10 percent, then conduct the Threshold
Friction Velocity test in Section II.2. of this in order to
determine whether the disturbed surface area is stabilized according
to paragraph (b)(16)(ii)(E) of this section.
(i) For standing vegetation that consists of large, separate
vegetative structures (for example, shrubs and sagebrush), select a
survey area representing the disturbed surface that is the shape of
a square with sides equal to at least ten (10) times the average
height of the vegetative structures. For smaller standing
vegetation, select a survey area of three (3) feet by 3 feet.
(ii) Count the number of standing vegetative structures within
the survey area. Count vegetation which grows in clumps as a single
unit. Where vegetation of different height and width exists, count
it in groups with similar dimensions within the survey area. For
each group, calculate the frontal silhouette area for the vegetative
structures according to the following equations:
(Average height) x (Average width) = Average Eq. 6
Dimensions
(Average Dimensions) x (Number of Vegetation) = Eq. 7
Frontal Silhouette Area
Frontal Silhouette Area of Group 1 + Frontal Silhouette Eq. 8
Area of Group 2 (etc..) = Total Frontal Silhouette
Area
(Total Frontal Silhouette Area/Survey Area) x 100 = Eq. 9
Percent Cover of Standing Vegetation
(Ensure consistent units of measurement, e.g. square meters or
square inches when calculating percent cover.)
(iii) Within a disturbed surface area that contains multiple
types of vegetation with each vegetation type uniformly distributed,
results of the percent cover associated with the individual
vegetation types may be added together.
(iv) Repeat this procedure on an additional two (2) distinct
survey areas representing the disturbed surface and average the
results.
5. Alternative Test Methods
Alternative test methods may be used upon obtaining the written
approval of the EPA.
[FR Doc. 98-20147 Filed 7-31-98; 8:45 am]
BILLING CODE 6560-50-U