[Federal Register Volume 63, Number 118 (Friday, June 19, 1998)]
[Proposed Rules]
[Pages 33597-33605]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-16403]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 81

[ID 21-7001; FRL-6113-4]


Designation of Areas for Air Quality Planning Purposes: State of 
Idaho and the Fort Hall Indian Reservation

AGENCY: Environmental Protection Agency.

ACTION: Notice of proposed rulemaking.

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SUMMARY: In this action, the Environmental Protection Agency (EPA) 
proposes to revise the designation for particulate matter with an 
aerodynamic diameter of less than a nominal 10 microns (PM-10) for the 
Power-Bannock Counties PM-10 nonattainment area by creating two 
distinct nonattainment areas that together cover the identical 
geographic area as the original nonattainment area. The revised areas 
would be divided at the boundary between State lands and the Fort Hall 
Indian Reservation, with one revised area comprised of State lands and 
the other revised area comprised of lands within the exterior boundary 
of the Fort Hall Indian Reservation. The redesignation is based upon a 
request from the State of Idaho, which is supported by monitoring and 
modeling information. Both areas would retain PM-10 nonattainment 
designations and classification as moderate PM-10 nonattainment areas 
as a result of this proposed action.
    In a concurrent notice of proposed rulemaking published today, EPA 
is proposing to make a finding that the proposed PM-10 nonattainment 
area within the exterior boundary of the Fort Hall Indian Reservation 
failed to attain the National Ambient Air Quality Standards (NAAQS) for 
PM-10 by the applicable attainment date. Such a finding would, by 
operation of law, result in the reclassification of the proposed PM-10 
nonattainment area within the Fort Hall Indian Reservation to a serious 
PM-10 nonattainment area.
    EPA recently established a new standard for particulate matter with 
a diameter equal to or less than 2.5 microns and also revised the 
existing PM-10 standards. Today's proposal,

[[Page 33598]]

however, does not address these new and revised standards.

DATES: All written comments should be submitted to Steven K. Body, EPA 
Region 10, [Docket #ID 21-7001], at the address indicated below by July 
20, 1998.

ADDRESSES: Information supporting this action can be found in Public 
Docket No. [#ID 21-7001]. The docket is located at EPA, Region 10, 1200 
Sixth Avenue, Seattle WA 98101. The docket may be inspected from 9:00 
am to 4:30 pm on weekdays, except for legal holidays. A reasonable fee 
may be charged for copying.

FOR FURTHER INFORMATION CONTACT: Steven K. Body, EPA Region 10, Office 
of Air Quality (OAQ-107), EPA, Seattle, Washington, (206) 553-0782.

I. Background

    A portion of Power and Bannock Counties in Idaho is designated 
nonattainment for PM-10 \1\ and classified as moderate under sections 
107(d)(4)(B) and 188(a) of the Clean Air Act upon enactment of the 
Clean Air Act Amendments of 1990 (Act or CAA). See 40 CFR 81.313 (PM-10 
Initial Nonattainment Areas); see also 55 FR 45799 (October 31, 1990); 
56 FR 11101 (March 15, 1991); 56 FR 37654 (August 8, 1991); 56 FR 56694 
(November 6, 1991).\2\ For an extensive discussion of the history of 
the designation of the Power-Bannock Counties PM-10 nonattainment area, 
please refer to the discussion at 61 FR 29667, 29668-29670 (June 12, 
1996).
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    \1\ There are two pre-existing PM-10 NAAQS, a 24-hour standard 
and an annual standard. See 40 CFR 50.6. EPA promulgated these NAAQS 
on July 1, 1987 (52 FR 24672), replacing standards for total 
suspended particulate with new standards applying only to 
particulate matter up to ten microns in diameter (PM-10). The annual 
PM-10 standard is attained when the expected annual arthimetic 
average of the 24-hour samples for a period of one year does not 
exceed 50 micrograms per cubic meter (ug/m3). Attainment of the 24-
hour PM-10 standard is determined by calculating the expected number 
of days in a year with PM-10 concentrations greater than 150 ug/m3. 
The 24-hour PM-10 standard is attained when the expected number of 
days with levels above the standard, averaged over a three year 
period, is less than or equal to one. See 40 CFR 50.6 and 40 CFR 
part 50, appendix K.
    \2\ The 1990 Amendments to the CAA made significant changes to 
the Act. See Public Law No. 101-549, 104 Stat. 2399. References 
herein are to the CAA as amended. The CAA is codified, as amended, 
in the United States Code at 42 U.S.C. 7401, et seq.
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    The Power-Bannock Counties PM-10 nonattainment area covers 
approximately 266 square miles in south central Idaho and comprises 
both trust and fee lands within the exterior boundary of the Fort Hall 
Indian Reservation and State lands in portions of Power and Bannock 
Counties. Approximately 75,000 people live in the nonattainment area, 
most of whom live in the cities of Pocatello and Chubbuck, which are 
located near the center of the nonattainment area on State lands. 
Approximately 15 miles northwest of downtown Pocatello is an area known 
as the ``industrial complex,'' which includes the two major stationary 
sources of PM-10 in the nonattainment area. The boundary between the 
Fort Hall Indian Reservation and State lands runs through the 
industrial complex. One of the major stationary sources of PM-10, FMC 
Corporation (FMC), is located primarily on fee lands within the 
exterior boundary of the Fort Hall Indian Reservation.\3\ The other 
major stationary source of PM-10 in the nonattainment area, J.R. 
Simplot Corporation (Simplot), is located on State lands immediately 
adjacent to the Reservation.
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    \3\ EPA has learned that a portion of the FMC facility is 
located on State lands. This issue is discussed in more detail 
below.
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    The State of Idaho has established and operates four PM-10 State 
and Local Air Monitoring Stations (SLAMS) in the current Power-Bannock 
Counties PM-10 nonattainment area, all of which are on State lands (the 
State monitors). All of the State monitors meet EPA SLAMS network 
design and siting requirements, set forth at 40 CFR part 58, appendices 
D and E. There have been no violations of the annual PM-10 standard at 
any of the State monitors since 1990. No levels above the 24-hour 
standard have been recorded at any of the State monitors since January 
of 1993.
    The Shoshone-Bannock Tribes began operating a PM-10 monitor on the 
portion of the nonattainment area within the exterior boundary of the 
Reservation in February 1995. Prior to this time, the Tribes relied on 
data from the State operated samplers for area designations and 
classifications. This reliance was due to a lack of resources to 
establish and operate their own Tribal monitoring stations. In 1994 the 
Tribes requested and EPA granted the Tribes additional program support 
grant funds to enable the Tribes to establish their own monitoring 
stations to collect ambient air quality data representative of 
conditions on the Reservation and to generate data to support Tribal 
air quality planning efforts. This monitor, called the ``Sho-Ban 
site,'' is located approximately 100 feet north of the FMC facility 
across a frontage road. Due to operational problems with the sampler 
and quality assurance problems, valid data were not reported for this 
monitor until October 1, 1996. Also in October 1996, the Tribes 
initiated monitoring at two new sites. The ``primary site'' is located 
approximately 100 feet north of the FMC facility across the frontage 
road, 600 feet east of the Sho-Ban site and approximately 600 feet from 
the boundary between the Fort Hall Indian Reservation and State lands. 
The ``Tribal background site'' is approximately one and one-half miles 
southwest of the FMC facility upwind of the predominant wind direction 
from the industrial complex. All three monitoring sites are owned by 
the Tribes and operated by a contractor for the Tribes. The Tribal 
monitoring sites meet EPA SLAMS network design and siting requirements, 
set forth at 40 CFR part 58, appendices D and E. Both the Sho-Ban and 
Primary sites on the Reservation portion of the nonattainment area have 
recorded numerous PM-10 concentrations above the level of the 24-hour 
PM-10 NAAQS since October 1996.\4\
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    \4\ Private industry operated a seven station air monitoring 
network, funded by FMC and Simplot, on and near the industrial 
complex from October 1, 1993, through September 30, 1994 (EMF 
monitors). There were no measured PM-10 concentrations above the 
level of the 24-hour PM-10 NAAQS (150 ug/m3) at any of the EMF 
stations. EMF Site #2, however, which was on the Fort Hall Indian 
Reservation less than 300 yards east of where the primary site is 
now located, reported several 24-hour concentrations of PM-10 at or 
near the level of the NAAQS. EMF Site #2 also reported an annual 
concentration of 55.1 ug/m3 for the one year period the network was 
in operation. This is 10% greater than the 50 ug/m3 level of the 
annual PM-10 NAAQS. Because the EMF network did not collect a 
calendar year's worth of data, EPA concluded that data from EMF Site 
#2 did not document a violation of the annual NAAQS. See 61 FR 
66602, 66604 (December 18, 1996). EPA also stated, however, that the 
number of the recorded 24-hour concentrations at or near the level 
of the standard and the high annual concentration for the one-year 
period EMF Site #2 was in operation indicated that a serious air 
quality problem continued in the Power-Bannock Counties PM-10 
nonattainment area. Id. This is confirmed by the more recent data 
from the Tribal monitors.
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II. This Action

A. Idaho's Request

    Pursuant to section 107(d)(3)(D) of the Act, the Governor of any 
State, on the Governor's own motion, is authorized to submit to the 
Administrator a revised designation of any area or portions thereof 
within the State. On April 16, 1998, the State of Idaho submitted to 
EPA a request to revise the designation of the Power-Bannock Counties 
PM-10 nonattainment area to split the nonattainment area into two 
separate nonattainment areas at the boundary between the Fort Hall 
Indian Reservation and State lands. Together, the two nonattainment 
areas would cover the same geographic area as the

[[Page 33599]]

existing Power-Bannock Counties PM-10 nonattainment area.
    In support of its request, the State of Idaho noted that the State 
has the primary PM-10 planning responsibility under the Clean Air Act 
for State lands within the nonattainment area, whereas EPA and the 
Tribes have the primary PM-10 planning responsibility for the Tribal 
lands within the nonattainment area. The State also noted that it has 
largely completed the PM-10 planning and implementation of control 
measures for the PM-10 sources located on State lands within the 
nonattainment area whereas no controls have been proposed or imposed on 
sources in the Tribal portion of the nonattainment area.
    The State also supported its request with monitoring data which 
shows that State monitors have not recorded any PM-10 concentrations 
above the level of the 24-hour PM-10 NAAQS since January 1993 and that 
the State lands within the nonattainment area have attained the PM-10 
NAAQS. In addition, the State provided an analysis of pollution 
concentrations recorded at the Tribal primary site and the Sho-Ban site 
as a function of wind direction which shows that violations of the PM-
10 NAAQS at the Tribal sites are not the result of emissions from 
sources located on State lands. The State also provided modeling 
information to support its assertion that sources on State lands are 
not contributing to the violations of the PM-10 NAAQS that have been 
recorded at the Tribal monitors.
    On May 21, 1998, the Shoshone-Bannocks Tribes and FMC submitted to 
the State of Idaho documents opposing Idaho's request to EPA to split 
the nonattainment area into two nonattainment areas. The Tribes and FMC 
contend that the State failed to follow Idaho law in submitting the 
request to EPA without first providing public notice and opportunity 
for comment. The Tribes also expressed concern that splitting the area 
into two PM-10 nonattainment areas at the State-Reservation boundary 
could result in a less comprehensive approach to air quality planning 
in the area. In addition to its contention that the State failed to 
comply with State requirements for public notice and opportunity for 
public comment, FMC further contends that the State failed to comply 
with the Clean Air Act in making its request and noted that part of the 
FMC facility is located on State lands.
    On May 29, 1998, Idaho provided EPA with a letter from the Idaho 
Attorney General's Office stating that public notice and opportunity to 
comment were not required under State law. The letter also responded to 
the other issues raised by FMC and asked EPA to move forward on the 
State's request to split the nonattainment area. The State also 
provided EPA with a copy of the State's letter responding to the issues 
raised by the Tribes. Copies of the letters from FMC and the Tribes to 
the State and from the State to EPA and the Tribes are in the Docket 
for this proposal.

B. EPA's Proposed Action on Idaho's Request

    In determining whether to approve or deny a State's request for a 
revision to the designation of an area under section 107(d)(3)(D), EPA 
believes it is appropriate to consider the same factors Congress 
directed EPA to consider when EPA initiates a revision to a designation 
of an area on its own motion under section 107(d)(3)(A). These factors 
include ``air quality data, planning and control considerations, or any 
other air quality-related considerations the Administrator deems 
appropriate.'' Based on the information submitted by Idaho and other 
information available to EPA, EPA believes that the air quality data, 
planning and control considerations, and other air quality-related 
considerations support the State's request to revise the Power-Bannock 
Counties PM-10 nonattainment area into two PM-10 nonattainment areas at 
the boundary between the Fort Hall Indian Reservation and State lands. 
EPA therefore proposes to create two separate nonattainment areas in 
place of the existing Power-Bannock Counties PM-10 nonattainment area. 
One area, to be called the ``Portneuf Valley PM-10 Nonattainment 
Area'', would consist of the existing portion of the Power-Bannock 
Counties PM-10 nonattainment area outside of the exterior boundary of 
the Fort Hall Indian Reservation and under the regulatory jurisdiction 
of the State of Idaho. The other area, to be called the ``Fort Hall PM-
10 nonattainment area,'' would consist of the existing portion of the 
nonattainment area within the exterior boundary of the Fort Hall 
Reservation. Both areas would continue to be designated nonattainment 
for PM-10 and classified as moderate should this proposal be finalized 
by EPA.
    Although the comments from the Tribes and FMC were directed to the 
State in the context of the State proceeding, and not to EPA, EPA has 
considered those issues in making this proposal, as is discussed in 
more detail below. The Tribes and FMC will also have an opportunity to 
raise those and other issues in the public comment period on this 
proposal.
1. Air Quality Data and Other Air Quality-Related Considerations
    As stated above, there have been no violations of the annual PM-10 
standard at any of the four State monitoring sites since 1990 and no 
levels above the 24-hour standard have been recorded at any of the 
State sites since January of 1993. The data recorded at the State 
monitors also show a decline in the yearly annual average at each State 
monitoring station since 1993 and, with the exception of the Sewage 
Treatment Plant (STP) monitoring station, a decline in the highest and 
second highest 24-hour PM-10 readings for each year at each of the 
State monitoring stations. The STP monitoring site did record a 24-hour 
PM-10 concentration of 149 ug/m3, just below the level of the 24-hour 
standard of 150 ug/m3. Even if that monitoring site had recorded one 
PM-10 concentration above the standard, however, the 24-hour PM-10 
standard would not have been violated because the site operates on an 
everyday sampling schedule and the expected exceedence rate, averaged 
over a three year period, would have been less than 1.1. Moreover, the 
second highest 24-hour PM-10 readings for each year at the STP site 
have remained fairly constant since 1993, and there has been a decline 
in the yearly PM-10 annual average at the STP site since 1992. In 
summary, the State monitors show attainment of the PM-10 standard in 
the State portion of the nonattainment area, as well as a general 
decline in the PM-10 values recorded on the State monitors.
    In contrast, the monitors located within the Tribal portion of the 
nonattainment area continue to show numerous levels above the standard. 
Although the monitors did not begin recording valid data until October 
1996, the number of PM-10 concentrations above the level of the 24-hour 
PM-10 NAAQS between October and December 1996 resulted in a violation 
of the 24-hour PM-10 NAAQS as of December 31, 1996, the attainment date 
for the area.<SUP>5</SUP> Appendix K of 40 CFR part 50, contains 
``gapfilling'' techniques for situations where less than three complete 
years of data are available. Using the gapfilling techniques of 
appendix K, the number

[[Page 33600]]

of exceedences reported from the Sho-Ban and primary sites during the 
last three months of 1996 represent a violation of the 24-hour PM-10 
NAAQS. The expected exceedence rate of the 24-hour standard, averaged 
over the years 1994, 1995, and 1996, from these two monitors is greater 
than 1.1, even if the days during which the monitors did not operate or 
collect valid data had reported zero PM-10 levels. Numerous levels 
above the standard have been recorded since December 31, 1996, as well.
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    \5\ The Power-Bannock Counties PM-10 nonattainment area 
originally had an attainment date of December 31, 1994, see section 
188(a) and (c)(1), but the area could not demonstrate attainment by 
that date. At the request of the State of Idaho, EPA granted the 
area two one-year extensions of the attainment date, in accordance 
with section 188(d) of the CAA. See 60 FR 44452 (August 28, 1995) 
(proposed action on first extension); 61 FR 20730 (May 8, 1996) 
(final action on first extension); 61 FR 66602 (December 18, 
1996)(direct final action on second extension).
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    In addition to the monitoring data which document that the monitors 
on State lands show attainment of the PM-10 standard, the State of 
Idaho also provided monitoring and modeling information to support its 
request to divide the current nonattainment area at the State-
Reservation boundary. The State first presented information to 
demonstrate that there are two separate areas of air quality impacts 
and sources within the current nonattainment area. One area, which the 
State refers to as the ``urban complex,'' encompasses the City of 
Pocatello and is solely on State lands. The other area is the 
industrial complex, which includes FMC within the Fort Hall Indian 
Reservation and J.R. Simplot on State lands. Based on chemical analysis 
of the particulate collected on the filters from both State and Tribal 
monitors and comparing these results to the chemical composition of 
emissions from various sources, the State determined that the urban 
area is impacted by PM-10 emissions from residential wood burning, 
traffic, and commercial establishments. In contrast, the industrial 
complex is impacted by industrial emissions.
    Analysis of the 1993 dispersion modeling used by the State in 
developing its SIP shows that the urban complex and the industrial 
complex have different sources contributing to the high PM-10 levels 
that have been recorded in each area. The modeling also shows that 
there is no evidence of significant mixing of emissions between the 
industrial complex and the urban complex. Appendix A to the State's 
request contains a detailed discussion of these modeling results, 
including an analysis of four specific days with worst case 
meteorology. In general, this analysis consists of PM-10 concentration 
isopleth graphs that demonstrate two separate areas of maximum 
concentrations of PM-10, one located over the urban complex and the 
second located over the FMC and J.R. Simplot industrial facilities.
    The State also showed that, within the industrial complex, it is 
possible to separate the impacts of sources on Tribal lands from 
sources on State lands at the State-Reservation boundary. In the 
process of developing the PM-10 plan for the Tribal portion of the 
nonattainment area, EPA constructed ``pollution wind roses'' from the 
ambient PM-10 monitoring data from two of the Tribal monitors (the Sho-
Ban site and the primary site) and the meteorological station at the 
primary site. ``Pollution wind roses'' relate pollutant concentration 
measurements (in this case PM-10 levels) and the wind direction that 
occurred during that measurement. The State reviewed pollution wind 
roses for the period from October 1996 and May 1997. The data show 
that, on days when the primary site recorded values greater than the 
24-hour standard (150 ug/m3), the wind was blowing from the FMC 
facility toward the monitor, i.e., from the southwest. Similarly, on 
days when the Sho-Ban site recorded values greater than the standard, 
the wind was blowing from FMC facility toward the Sho-Ban monitor, 
i.e., from the south. In contrast, on days when the wind was blowing 
from State lands, particularly Simplot, toward the primary and Sho-Ban 
monitors, high PM-10 values were not recorded on the monitors. The 
State concludes from this information that sources on State lands, 
particularly Simplot, are effectively controlled and do not contribute 
to violations of the PM-10 NAAQS on State or Tribal lands.
    EPA evaluated the information submitted by the State along with the 
more recent information provided by FMC to the State that a portion of 
the FMC facility is located on State lands. FMC property extends 
approximately 7000 feet east-west along a frontage road of which 1100 
feet appears to extend east onto State lands. The only PM-10 sources of 
potential significance on this portion of FMC property (i.e., on State 
lands) are a portion (approximately 1100 feet) of the north and south 
main ore shale storage piles and a small number of unpaved access 
roads. The piles are approximately 1500 feet long and 300 feet wide of 
which two-thirds extend onto State lands. EPA estimates that PM-10 
emissions from that portion of the FMC facility located on State lands 
account for only 89 pounds of the 12,021 pounds per day of total PM-10 
emissions from the facility, or less than 1% of total FMC emissions of 
PM-10. When the ``pollution rose'' graphs relied on by the State are 
laid over a map of the area, it is apparent that violations at the 
primary site occur when winds are blowing from the south to west-
southwest, which is down wind of the FMC calcining operations, furnace 
building, and slag pit operations. Violations occur at the Sho-Ban site 
when the winds are blowing from the west-southeast to east-southwest, 
which is again downwind from the FMC calcining operations, furnace 
building, and slag pit operations. Violations have not occurred with a 
wind direction blowing from the eastern portion of the FMC property, 
which is the portion of the FMC facility located on State lands, or 
from the Simplot facility, which is also located on State lands. Based 
on the small percentage of emissions from the FMC PM-10 sources located 
on State lands to total FMC PM-10 emissions and EPA's review of the 
pollution and wind roses for the area, EPA does not believe that the 
new information provided by FMC--that part of the FMC facility is 
located on State lands--alters the analysis provided by the State to 
support its request to split the existing nonattainment area into two 
nonattainment areas at the State-Reservation boundary. In summary, EPA 
agrees with the State's analysis and with the State's conclusion that 
emissions from sources on State lands do not appear to be contributing 
to the exceedences that have been recorded on the Tribal monitors. In 
light of the recent information provided by FMC to the State, however, 
EPA specifically requests comment on this issue.
2. Planning and Control Considerations
    The current Power-Bannock Counties PM-10 nonattainment area 
encompasses two different regulatory jurisdictions: the State of Idaho 
for the State portion of the nonattainment area and the Shoshone-
Bannock Tribes and EPA for the Reservation portion of the nonattainment 
area. Under the Clean Air Act, the State has the primary PM-10 planning 
responsibilities for the State portion of the nonattainment area. See 
CAA sections 110 and 189. In furtherance of those planning obligations, 
the State of Idaho, along with several local agencies, developed and 
implemented control measures on PM-10 sources located on State lands 
within the Power-Bannock Counties PM-10 nonattainment area. The State 
submitted these control measures in 1993 for the Power-Bannock Counties 
PM-10 nonattainment area as part of its moderate PM-10 nonattainment 
State Implementation Plan (SIP) under section 189(a) of the Act. These 
control measures include a comprehensive residential wood combustion 
program, including a mandatory woodstove curtailment program; stringent 
controls on fugitive road dust, including controls on winter road 
sanding and a limited

[[Page 33601]]

unpaved road paving program; and a revised operating permit that 
represents reasonably available control technology (RACT) for the J.R. 
Simplot facility, the only major stationary source of PM-10 on the 
portion of the nonattainment area on State lands. Although EPA has not 
yet taken final action to approve the State's moderate PM-10 SIP for 
the area, EPA has previously stated (based on EPA's preliminary review 
in the context of approving the State's requests for extensions of the 
attainment date) that these control measures substantially meet EPA's 
guidance for reasonably available control measures (RACM), including 
RACT, for sources of primary particulate on the State portion of the 
nonattainment area. See 61 FR 66602, 66604-66605 (December 18, 1996).
    The effect of these control measures on air quality can be seen in 
the reported ambient PM-10 measurements at the State monitoring sites. 
As discussed above, there have been no violations of the annual PM-10 
standard since 1990 at any of the State monitoring sites, no violations 
or exceedences of the 24-hour PM-10 standard at any of the State sites 
since January 1993, and a general decline in the reported ambient PM-10 
concentrations at the State sites since 1993. The beginning of the 
decline in the ambient concentrations roughly coincides with the period 
when the State began to impose the PM-10 control measures discussed 
above. These facts support the State's assertion that the State's PM-10 
planning efforts have been effective.
    In its request to split the nonattainment area, the State also 
discusses how it is addressing the deficiencies that EPA had previously 
identified in the State's SIP submission. The State has advised EPA 
that it will submit a SIP revision in the near future that addresses 
these deficiencies. The deficiencies previously identified by EPA 
include the State's failure to address PM-10 precursors in the State's 
emissions inventory and control strategy and the fact that the 1993 SIP 
did not demonstrate attainment in the downtown Pocatello area due to 
road dust emissions. The State also plans to address PM-10 emissions 
from Bannock-Paving Company, Incorporated. A summary of the State's 
plans with respect to addressing these deficiencies is presented below.
    Section 189(e) of the Act states that the control requirements 
applicable to major stationary sources of PM-10 shall also apply to 
major stationary sources of PM-10 precursors, except where EPA 
determines that major stationary sources of PM-10 precursors do not 
contribute significantly to PM-10 levels which exceed the PM-10 
standard in the area. At the time the State developed and submitted its 
SIP, PM-10 precursors were not thought to contribute to PM-10 levels 
which exceeded the PM-10 standard in the Power-Bannock Counties PM-10 
nonattainment area. However, subsequent monitoring data and analysis of 
the particulates collected on the filters by the State in January 1993 
showed significant levels of secondary aerosol and necessitated a 
reevaluation of the contribution of PM-10 precursors to the 
nonattainment problem in the Power-Bannock Counties PM-10 nonattainment 
area.<SUP>6</SUP> Accordingly, in conjunction with EPA and the Tribes, 
the State developed a work plan for analyzing and addressing the 
contribution of PM-10 precursors to the nonattainment problem in the 
Power-Bannock Counties PM-10 nonattainment area.
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    \6\ Secondary aerosol particulates are small particles formed in 
the atmosphere through chemical reactions from emissions of 
precursor gases.
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    Since PM-10 precursors were first identified in particulate samples 
collected in January 1993 as a potential contributor to the 
nonattainment problem in the nonattainment area, however, no levels 
above the standard have been recorded at any of the State monitors. 
Instead, it appears that PM-10 precursors represent a significant 
fraction of the total PM-10 mass loading only during very specific 
meteorological conditions--cold stagnant winter days with relative high 
humidity. There have been only two days between 1986 and 1997 in which 
violations of the PM-10 NAAQS in the Power-Bannock Counties PM-10 
nonattainment area have been attributed to secondary aerosols. Based on 
the fact that the State monitors have not recorded an exceedence since 
January 1993, it does not appear that major stationary sources of PM-10 
precursors contribute significantly to PM-10 levels which exceed the 
standard within the portion of the Power-Bannock Counties PM-10 
nonattainment area located on State lands. Although EPA reserves final 
determination on this issue until the State submits its SIP revision 
and EPA takes final action on that revision, EPA's preliminary 
determination is that stationary sources of PM-10 precursors do not 
appear to contribute significantly to PM-10 levels which exceed the 
standard on the portion of the nonattainment area on State lands. Final 
action on such a finding would mean that the State will not be required 
to further address PM-10 precursors in completing its SIP planning 
obligations for the State portion of the Power-Bannock Counties PM-10 
nonattainment area.
    EPA is aware that the Shoshone-Bannock Tribes and citizens in the 
Power-Bannock counties PM-10 nonattainment area believe that 
particulate precursors contribute to air quality problems in the area 
and should be addressed. EPA shares this concern. On July 18, 1997, EPA 
promulgated new, more stringent, air quality standards for particulate 
matter with an aerodynamic diameter equal to or less than 2.5 microns 
(PM-2.5). These standards were promulgated to address the serious 
health effects associated with these very small particles, of which 
secondary aerosol makes up a significant fraction. EPA, the State, and 
the Tribes are just now in the process of establishing PM-2.5 air 
monitoring stations to better define and characterize the nature and 
extent of the fine particulate air quality problem in the Portneuf 
Valley and Fort Hall area. EPA's preliminary determination that PM-10 
precursors do not need to be addressed by the State in its current PM-
10 planning process for the Portneuf Valley area should not be 
interpreted to imply that particulate precursors will not need to be 
addressed under the new PM-2.5 standard. To the contrary, EPA believes 
it is likely that particulate precursors will need to be addressed in 
the Portneuf Valley and Fort Hall area under the new PM-2.5 standard.
    Another deficiency previously identified by EPA in the State's PM-
10 planning process was the State's inability to model attainment of 
the PM-10 standard in the Pocatello urban area due to projected 
fugitive road dust emissions. The State has long suspected that the 
emission factors it used to estimate road dust emissions in the 
emissions inventory and attainment demonstration (AP-42 emission 
factors) were far too high. Idaho therefore commissioned a study to 
measure road dust emissions in the Pocatello area and to develop new 
emission factors if appropriate. Preliminary results from the study, 
which are included in the Docket for this rulemaking, indicate that the 
emission factors derived from the study are, on average, 68% less than 
the AP-42 emission factors used to develop the original emissions 
inventory. The State therefore asserts that the modeled exceedences of 
the PM-10 standard in the downtown Pocatello area appear to be due to 
the erroneously high road dust emission factors and are not 
representative of actual ambient conditions. Although EPA defers a 
final

[[Page 33602]]

determination on this issue until it receives and reviews the State's 
SIP revision, EPA tentatively agrees with the State that additional 
controls on road dust emissions do not appear to be necessary to 
demonstrate attainment in the State portion of the nonattainment area.
    As discussed above, the State also intends to address emissions 
from Bannock Paving Company, Incorporated (Bannock Paving), in its SIP 
revision. Bannock Paving operates five portable facilities that operate 
in attainment and nonattainment areas in the State of Idaho, each of 
which is a minor source of PM-10.<SUP>7</SUP> The State has submitted 
the existing construction permits for the Bannock Paving facilities, 
which were issued under a federally enforceable permit program. The 
existing permits contain several emission limitations that control PM-
10, such as opacity limits, grain loading standards, and requirements 
for controlling fugitive emissions, and the State asserts that the 
level of controls currently imposed on Bannock Paving in these 
construction permits represents RACT. The State has also advised EPA 
that it intends to consolidate all of the existing construction permits 
the State has issued for Bannock Paving into a new operating permit for 
Bannock Paving and submit the revised permit and a demonstration that 
the permit constitutes RACT in its SIP revision. EPA defers a final 
determination on this issue until EPA has received the State's SIP 
revision, but notes that Bannock Paving is currently subject to 
controls on PM-10 emissions.
---------------------------------------------------------------------------

    \7\ The State's request to split the nonattainment area states 
that Bannock Paving is a major stationary source of PM-10. Based on 
EPA's review of the five State permits for Bannock Paving and 
conversations with the State, EPA understands that the statement in 
the State's request was in error and that each of the Bannock Paving 
facilities is a minor source of PM-10, even when the portable 
facilities co-locate.
---------------------------------------------------------------------------

    Based on the controls that have been previously imposed by the 
State on the sources of PM-10 on State lands within the nonattainment 
area and the discussion by the State of its soon-to-be submitted SIP 
revision in support of its request to split the nonattainment area, EPA 
believes that the State has largely completed its PM-10 planning 
obligations under the Clean Air Act. Indeed, on its portion of the 
nonattainment area, the State is demonstrating and, in all likelihood 
will continue to demonstrate, attainment of the PM-10 NAAQS. In light 
of the information that some sources of PM-10 emissions at the FMC 
facility are located on State lands, however, the State's SIP revision 
will also need to address the PM-10 emissions from that portion of the 
FMC facility located on State lands.
    In contrast, the PM-10 requirements for the Tribal portion of the 
nonattainment area are still under development.<SUP>8</SUP> Because of 
long-standing concerns about the air quality in the Power-Bannock 
County PM-10 nonattainment area, EPA has been developing a Federal 
Implementation Plan (FIP) for the portion of the nonattainment area 
within the exterior boundary of the Fort Hall Indian Reservation. The 
plan is being developed in close consultation with the Tribes and with 
extensive public participation. EPA intends to propose the FIP by the 
end of January 1999, and to finalize the FIP in the year 2000.
---------------------------------------------------------------------------

    \8\ In developing its PM-10 control strategy and SIP, the State 
did not seek to impose controls on any sources located on 
Reservation lands, including fee lands within the exterior boundary 
of the Reservation, or attempt to demonstrate to EPA that it had 
authority to promulgate and enforce air controls on Reservation 
lands.
---------------------------------------------------------------------------

    The Clean Air Act Amendments of 1990 greatly expanded the role of 
Indian Tribes in implementing the provisions of the Clean Air Act in 
Indian country. Section 301(d) of the Act authorizes EPA to issue 
regulations specifying the provisions of the Clean Air Act for which 
Indian tribes may be treated in the same manner as States. See CAA 
sections 301(d)(1) and (2). EPA promulgated the final rule under 
section 301(d) of the Act, entitled ``Indian Tribes: Air Quality 
Planning and Management,'' on February 12, 1998. 63 FR 7254. The rule 
is generally referred to as the ``Tribal Authority Rule'' or ``TAR''. 
The TAR implements the provisions of section 301(d) of the Act to 
authorize eligible Tribes to implement their own Tribal air programs. 
This includes a delegation of authority, to Tribes which meet certain 
requirements and request delegation, to develop, adopt and submit PM-10 
nonattainment area Tribal Implementation Plans for lands within the 
exterior boundary of Indian Reservations, including fee lands. Until 
promulgation of the TAR in February 1998, however, the Shoshone-Bannock 
Tribes did not have authority under the Clean Air Act to carry out the 
PM-10 planning responsibilities for the Tribal portion of the 
nonattainment area.
    The Shoshone-Bannock Tribes have expressed a strong interest in 
seeking authority under the TAR to regulate sources of air pollution on 
Tribal land under the Clean Air Act. Based on discussions with the 
Tribes, however, EPA believes that it will be at least several months 
before the Tribes will be ready to seek authority under the TAR to 
assume Clean Air Act planning responsibilities and that, even should 
they do so, the Tribes intend to build their capacity and seek 
authority for the various Clean Air Act programs over time, rather than 
all at once. EPA's understanding is that the Tribes continue to support 
EPA's efforts to promulgate a PM-10 nonattainment FIP for the Tribal 
portion of the nonattainment area notwithstanding the recent 
promulgation of the TAR.
    In summary, although the State has largely completed its PM-10 
planning responsibilities for the portion of the Power-Bannock Counties 
PM-10 nonattainment area on State lands, the planning responsibilities 
for the Tribal portion of the nonattainment area, including the FMC 
facility, are still under development.
3. Issues Raised by the Tribes and FMC to the State
    As discussed above, on May 21, 1998, the Shoshone-Bannock Tribes 
and FMC submitted to the State of Idaho documents opposing Idaho's 
request to EPA to split the nonattainment area into two nonattainment 
areas. Although the Tribes and FMC raised these issues in the State 
proceeding and will have an opportunity to raise the issues in the 
public comment period on this proposal, EPA has considered the issues 
raised by the Tribes and FMC prior to this proposal.
    The Tribes and FMC assert that the State failed to follow Idaho law 
(Idaho Administrative Procedures Act (IDAPA) 16.01.01.578.04) by 
submitting its request to EPA without first providing public notice and 
opportunity for comment. FMC further asserts that the State's request 
failed to comply with other provisions of IDAPA 16.01.01.578, as well, 
such as the requirement to consider certain factors enumerated in IDAPA 
16.01.01.578.02 for designating boundaries, and that public notice and 
comment was also required by Idaho Code sections 67-5221 and 5222, 
which govern rulemaking proceedings. The Idaho Attorney General's 
Office has advised EPA that the State's request to EPA to split the 
nonattainment area into two nonattainment areas is not subject to IDAPA 
16.01.01.578, which is entitled ``Designation of Attainment, 
Unclassifiable and Nonattainment Areas.'' The Attorney General's office 
has also advised EPA that the State's request to EPA is not a 
rulemaking under State law and is thus not subject to Idaho Code 
sections 67-5221 and 67-5222. EPA defers to the Idaho Attorney 
General's Office on these interpretations of Idaho law.

[[Page 33603]]

    The Tribes and FMC also expressed concern that splitting the area 
into two PM-10 nonattainment areas at the State-Reservation boundary 
could result in a less comprehensive approach to air quality planning 
in the area. EPA was previously aware of the Tribes concern on this 
issue based on several meetings between the EPA and the Tribes 
regarding the State's request. EPA has carefully considered this 
concern, especially the interests of the Shoshone-Bannock Tribes, but 
continues to believe that the proposed split is in the overall best 
interest of the area as a whole. The State has largely completed its 
PM-10 planning requirements for the area. Therefore, EPA does not 
believe that splitting the nonattainment area will result in a less 
comprehensive approach to PM-10 planning for the existing Power-Bannock 
Counties PM-10 nonattainment area as a whole. If some area in or near 
the City of Pocatello or the Fort Hall Indian Reservation is later 
identified as a nonattainment area for PM-2.5, EPA will consider at the 
time of such identification whether, based on air quality data, 
planning and control considerations, or other air quality-related 
considerations, the planning requirements for PM-2.5 are best carried 
out by having a single nonattainment area or having two nonattainment 
areas divided at the State-Reservation boundary or in some other way.
    In addition to its contention that the State failed to comply with 
State requirements for public notice and opportunity for public 
comment, FMC further contends that the State failed to comply with the 
Clean Air Act in making its request to EPA. FMC argues that sections 
110(a)(2) and 110(l) of the CAA also require that the State's request 
to EPA be subject to public notice and comment before submission to 
EPA. EPA disagrees. Sections 110(a)(2) and 110(l) of the CAA require a 
State to provide public notice and comment at the State level for State 
Implementation Plans (SIPs) and SIP revisions. The State's request to 
EPA to split the Power-Bannock Counties PM-10 nonattainment area is not 
a SIP or SIP revision, and is therefore not subject to the requirements 
of section 110 of the CAA. FMC further argues that the State's request 
is incomplete as a matter of federal law because it does not address 
the factors enumerated in section 107(d)(3)(E) of the CAA. That 
section, however, by its terms applies only to requests to 
redesignation of an area from nonattainment to attainment. The State 
has not requested that the portion of the Power-Bannock Counties PM-10 
nonattainment area located on State lands be redesignated from 
nonattainment to attainment. As stated above, the proposed Portneuf 
Valley PM-10 nonattainment area will retain its classification as a 
moderate PM-10 nonattainment area as a result of this proposed action. 
Therefore, section 107(d)(3)(E) is inapplicable to the State's request 
and EPA's proposed action. Finally, FMC asserts that splitting the 
nonattainment area into two nonattainment areas is inconsistent with 
section 107(d)(1) of the CAA absent a showing that ``other sources in 
the area are not collectively causing or contributing to a violation of 
the NAAQS.'' As stated above, based on information currently available 
to EPA, EPA believes the State has shown that sources located on State 
lands are not causing or contributing to the violations of the PM-10 
NAAQS that have been recorded on the Tribal monitors. Therefore, EPA 
believes that splitting the Power-Bannock Counties PM-10 nonattainment 
areas into two nonattainment areas at the State-Reservation boundary is 
consistent with section 107(d)(1) of the CAA.
    FMC also asserts that a portion of the FMC facility is located on 
State lands. As discussed above, EPA has considered the impact of this 
fact on the State's request, and continues to believe it is appropriate 
to split the nonattainment area at the State-Reservation boundary. 
Based on the fact that more of the FMC facility is located on State 
lands than was previously understood by EPA, however, EPA specifically 
invites comment on whether, as an alternative proposal, it would be 
appropriate to split the current Power-Bannock Counties PM-10 
nonattainment area at the State-Reservation boundary, except to include 
in the proposed Fort Hall PM-10 nonattainment area that portion of the 
FMC facility located within State lands.
4. Summary
    Based on the information provided by the State in its request and 
other information available to EPA, EPA proposes to grant the State's 
request to split the Power-Bannock Counties PM-10 nonattainment area 
into two nonattainment areas along the State-Reservation boundary. The 
monitors located on State lands have not registered a violation or even 
an exceedence of the PM-10 NAAQS for more than five years. In addition, 
modeling and monitoring information shows that sources on State lands 
within the nonattainment area are not contributing to the exceedences 
of the PM-10 NAAQS that have been recorded on the Tribal monitors. 
Finally, the State has imposed controls on major sources of PM-10 
within the State portion of the nonattainment area and the monitors 
sited on State lands have shown a general decline in the ambient PM-10 
values recorded since the State first imposed these controls. In 
contrast, the monitors situated on Tribal lands have recorded numerous 
exceedences of the PM-10 NAAQS since they began operation in 1996, and 
EPA has not yet completed rulemaking action that would impose controls 
on the major sources of PM-10 in the Tribal portion of the 
nonattainment area. EPA therefore believes that air quality data, 
planning and control considerations, and other air quality-related 
information support dividing the current Power-Bannock Counties PM-10 
nonattainment area into two separate PM-10 nonattainment areas at the 
State-Reservation boundary, as requested by the State.

III. Implications of this Proposed Action

A. Area Classifications and Designations

    If EPA takes final action on this proposal, the current Power-
Bannock Counties PM-10 nonattainment area would be split into two 
nonattainment areas that together cover the identical geographic area 
of the current nonattainment area. The revised areas would be divided 
at the boundary between State lands and the Fort Hall Indian 
Reservation, with one revised area, to be referred to as the ``Portneuf 
Valley PM-10 nonattainment area,'' comprised of State lands and the 
other revised area, referred to as the ``Fort Hall PM-10 nonattainment 
area,'' comprised of lands within the exterior boundary of the Fort 
Hall Indian Reservation.
    The table below indicates how EPA is proposing to revise the PM-10 
designation for the current Power-Bannock Counties PM-10 nonattainment 
area, for both Idaho and the Fort Hall Indian Reservation in 40 CFR 
section 81.313.

[[Page 33604]]



                                                                   Part 81.313--PM-10                                                                   
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Designation                                           Classification                    
             Designated area             ---------------------------------------------------------------------------------------------------------------
                                              Date                        Type                        Date                        ype                   
--------------------------------------------------------------------------------------------------------------------------------------------------------
Idaho...................................  ...........  Nonattainment............................  ...........  Moderate.                                
Portneuf Valley Area:                                                                                                                                   
    T.5S, R.34E Sections 25-36..........                                                                                                                
    T.5S, R.35E Section 31..............                                                                                                                
    T.6S, R.34E Sections 1-36...........                                                                                                                
    T.6S, R.35E Sections 5-9, 16-21, 28-                                                                                                                
     33.                                                                                                                                                
    Plus the West \1/2\ of Sections                                                                                                                     
     10,15,22,27,34.                                                                                                                                    
    T.7S, R.34E Sections 1-4, 10-14, and                                                                                                                
     24.                                                                                                                                                
    T.7S, R.35E Sections 4-9, 16-21, 28-                                                                                                                
     33.                                                                                                                                                
    Plus the West \1/2\ of Sections                                                                                                                     
     3,10,15,22,27,34.                                                                                                                                  
    T.8S, R.35E Section 4...............                                                                                                                
    Plus the West \1/2\ of Section 3....                                                                                                                
  Fort Hall Indian Reservation..........  ...........  Nonattainment............................  ...........  Moderate.                                
    T.5S, R.34E Sections 15-23..........                                                                                                                
    T.5S, R.33E Sections 13-36..........                                                                                                                
    T.6S, R.33E Sections 1-36...........                                                                                                                
    T.7S, R.33E Sections 4,5,6..........                                                                                                                
    T.7S, R.34E Section 8...............                                                                                                                
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Both the Portneuf Valley PM-10 nonattainment area and the Fort Hall 
PM-10 nonattainment area would retain nonattainment designations as PM-
10 nonattainment areas as a result of this proposed action. In a 
concurrent notice of proposed rulemaking published today, however, EPA 
is proposing to make a finding that the proposed ``Fort Hall PM-10 
nonattainment area'' has failed to attain the PM-10 NAAQS by the 
applicable attainment date of December 31, 1996. If EPA makes a final 
determination that the proposed ``Fort Hall PM-10 nonattainment area'' 
has failed to attain the standard, that area would be reclassified as a 
serious PM-10 nonattainment area by operation of law under section 
188(b) of the Act, whereas the Portneuf PM-10 nonattainment area would 
remain classified as a moderate area.

B. New and Revised NAAQS for Particulate Matter

    On July 18, 1997, EPA promulgated revisions to both the annual and 
the 24-hour PM-10 standards and also established two new standards for 
particulate matter, both of which apply only to particulate matter 
equal to or less than 2.5 microns in diameter (PM-2.5). See 62 FR 
38651. The revised standards became effective on September 16, 1997. 
Although the revised suite of particulate matter standards reflects an 
overall strengthening of the regulatory standards for particulate 
matter, the revised 24-hour PM-10 standard, by itself, reflects a 
relaxation of that standard. In the preamble to the final rule setting 
the new and revised particulate matter standards, EPA stated that the 
pre-existing PM-10 standards would remain in effect for a period of 
time after the effective date of the new standard to ensure a smooth 
transition to the new standards. 62 FR 38701.
    Based on the transition policy announced by EPA in the preamble to 
the final rule setting the new and revised particulate standards, if 
EPA takes final action on its proposal to split the Power-Bannock 
Counties PM-10 nonattainment area, the existing PM-10 standards will 
ultimately be revoked in the two resulting nonattainment areas at 
different times. Because the monitors located on State lands showed 
attainment of the pre-existing PM-10 standard at the time promulgation 
of the revised PM-10 standards became effective, the pre-existing PM-10 
standard would continue to apply in the proposed Portneuf Valley PM-10 
nonattainment area until such time as EPA approves the control measures 
that have been adopted and implemented at the State level to bring the 
area into attainment with the pre-existing PM-10 NAAQS, and the State 
of Idaho has an approved SIP under section 110 of the Act for purposes 
of implementing the revised particulate matter standards. See 62 FR 
38701. The monitors in the Tribal portion of the nonattainment area, 
however, did not show attainment of the pre-existing PM-10 standard at 
the time promulgation of the revised PM-10 NAAQS became effective. 
Therefore, the pre-existing PM-10 NAAQS would continue to apply in the 
proposed Fort Hall PM-10 nonattainment area until EPA has completed its 
rulemaking under section 172(e) of the Act to prevent backsliding in 
those areas that had not attained the pre-existing PM-10 standard as of 
the date the relaxed PM-10 standard became effective. See 62 FR 39701. 
The rule promulgated under section 172(e) must require controls in the 
Fort Hall PM-10 nonattainment area, that are ``not less stringent than 
the controls applicable to areas designated nonattainment before the 
relaxation of the 24-hour PM-10 standard.'' EPA is also in the process 
of drafting a Federal Implementation Plan for the proposed Fort Hall 
PM-10 nonattainment area and expects that such FIP will meet the 
requirements promulgated by EPA under section 172(e).

C. Consultation With the Shoshone-Bannock Tribes

    As discussed above, EPA consulted with the Shoshone-Bannock Tribes 
prior to making this proposal. In particular, as discussed above, EPA 
is aware that the Tribes are concerned that splitting the area into two 
PM-10 nonattainment areas at the State-Reservation boundary could 
result in a less comprehensive approach to air quality planning in the 
area. As also discussed above, EPA has carefully considered the Tribes 
concerns but believes that the proposed split is in the overall best 
interest of the area as a whole because the State has largely completed 
its PM-10 planning requirements for the area. Therefore, EPA does not 
believe that splitting the nonattainment area will result in a less 
comprehensive approach to PM-10 planning for the existing Power-Bannock 
Counties PM-10 nonattainment area as a whole. In this regard, EPA would 
like to emphasize that until EPA promulgated the TAR in February of 
1998, the Tribes did not have authority under the Clean Air Act

[[Page 33605]]

to address the PM-10 planning requirements for the Reservation portion 
of the nonattainment area. EPA will carefully consider any additional 
comments or concerns raised by the Tribes during the public comment 
period on this action, including the Tribes preference for the name of 
the nonattainment area located within the Fort Hall Indian Reservation.

IV. Administrative Requirements

A. Executive Order (E.O.) 12866

    Under E.O. 12866 (58 FR 51735 (October 4, 1993)), EPA is required 
to determine whether regulatory actions are significant and therefore 
should be subject to Office of Management and Budget (OMB) review, 
economic analysis, and the requirements of the Executive Order. The 
Executive Order defines a ``significant regulatory action'' as one that 
is likely to result in a rule that may meet at least one of the four 
criteria identified in section 3(f), including, under paragraph (1), 
that the rule may ``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.''
    The OMB has exempted this action from review under E.O. 12866. In 
addition, the Agency has determined that EPA's proposal to split the 
nonattainment area into two nonattainment areas would result in none of 
the effects identified in section 3(f).

B. Regulatory Flexibility Act

    Under the Regulatory Flexibility Act, 5 U.S.C. 601 et seq, EPA must 
prepare a regulatory flexibility analysis assessing the impact of any 
proposed or final rule on small entities. 5 U.S.C. 603 and 604. 
Alternatively, EPA may certify that the rule will not have a 
significant economic impact on a substantial number of small entities. 
Small entities include small businesses, small not-for-profit 
enterprises, and government entities with jurisdiction over populations 
of less than 50,000.
    A regulatory flexibility screening analysis of this proposed action 
revealed that it would not have a significant adverse economic impact 
on a substantial number of small entities. A rule revising the 
designation of an area by creating two separate nonattainment areas 
under section 107(d)(3) of the CAA does not impose any new requirements 
on small entities. See Mid-Tex Electric Cooperative, Inc. v. FERC, 773 
F.2d 327 (D.C. Cir. 1985) (agency's certification need only consider 
rule's impact on entities subject to the requirements of the rule). To 
the extent that a State, Tribe or EPA must adopt new regulations, based 
on an area's nonattainment status, EPA will review the effect those 
actions have on small entities at the time EPA takes action on those 
regulations. Therefore, pursuant to 5 U.S.C. 605(b), I certify that the 
approval of the revised designation action proposed today does not have 
a significant economic impact on a substantial number of small entities 
within the meaning of those terms for RFA purposes.

C. Unfunded Mandates Reform Act

    Title II of the Unfunded Mandates Reform Act (UMRA), establishes 
requirements for Federal agencies to assess the effects of their 
regulatory actions on State, local, and Tribal governments and the 
private sector. Under the UMRA, EPA must assess whether various actions 
undertaken in association with proposed or final regulations include a 
Federal mandate that may result in estimated costs of $100 million or 
more to the private sector, or to State, local or tribal governments in 
the aggregate.
    EPA has determined that this proposed action, if promulgated, would 
not include a Federal mandate that may result in estimated costs of 
$100 million or more to either State, local, or tribal governments in 
the aggregate, or to the private sector. A rule revising the 
designation of an area by creating two separate nonattainment areas 
under section 107(d)(3) of the CAA does not impose any new requirements 
on the State, Tribes or the private sector. Redesignation is an action 
that affects the air quality status of a geographic area or the 
boundary of the geographic area and does not impose any regulatory 
requirements on the State, Tribes or private sector. Accordingly, EPA 
has determined that the proposed action does not include a Federal 
mandate that may result in estimated costs of $100 million or more to 
either State, local, or Tribal governments in the aggregate, or to the 
private sector.

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

    Executive Order 13045 (62 FR 19885 (April 23, 1997)) applies to any 
rule that EPA determines (1) ``economically significant'' as defined 
under Executive Order 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.
    This proposed action is not subject to Executive Order 13045 
because this is not an economically significant regulatory action as 
defined by Executive Order 12866.

V. Request for Public Comments

    EPA is, by this document, proposing that the PM-10 designation for 
the Power-Bannock Counties PM-10 nonattainment area be revised. The EPA 
is requesting public comments on all aspects of this proposal, 
including the appropriateness of the proposed designation and the scope 
of the proposed boundary. Public comments should be submitted to EPA at 
the address identified above by July 20, 1998.

List of Subjects in 40 CFR Part 81

    Environmental protection, Air pollution control, National parks, 
Wilderness areas.

    Authority: 42 U.S.C. 7401 et seq.

    Dated: June 10, 1998.
Chuck Findley,
Acting Regional Administrator, Region 10.
[FR Doc. 98-16403 Filed 6-18-98; 8:45 am]
BILLING CODE 6560-50-P