[Federal Register Volume 66, Number 103 (Tuesday, May 29, 2001)]
[Notices]
[Pages 29127-29128]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-13409]


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ENVIRONMENTAL PROTECTION AGENCY

[ND-001-0008; AD-FRL-6973-1]


Approval and Promulgation of State Implementation Plans; North 
Dakota; Notice of Potential Violations of the Prevention of Significant 
Deterioration Increments

AGENCY: Environmental Protection Agency (EPA).

ACTION: Information notice.

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SUMMARY: North Dakota has conducted a draft modeling analysis that 
shows numerous violations of the Class I prevention of significant 
deterioration (PSD) increments for sulfur dioxide (SO2) in 
four Class I areas. Those Class I areas include Theodore Roosevelt 
National Park, the Lostwood Wilderness Area, the Medicine Lakes 
Wilderness Area, and the Fort Peck Class I Indian Reservation. In a 
March 13, 2001 letter to EPA, the North Dakota Department of Health has 
committed to refine this modeling analysis and to subsequently adopt 
revisions to the State Implementation Plan (SIP) as may be necessary to 
address the increment violations that may be shown by the revised 
analysis. The purpose of this document is to inform the public of 
potential increment violations and of the commitments made by the North 
Dakota Department of Health to address the potential violations.

EFFECTIVE DATE: May 29, 2001.

ADDRESSES: Relevant documents are available for public inspection 
during normal business hours at the Air and Radiation Program, 
Environmental Protection Agency, Region VIII, 999 18th Street, Suite 
300, Denver, Colorado 80202-2405. Interested persons should contact the 
person listed below to arrange for a mutually agreeable time to view 
these documents.

FOR FURTHER INFORMATION CONTACT: Amy Platt, Air and Radiation Program, 
Environmental Protection Agency, Region VIII, (303) 312-6449.

SUPPLEMENTARY INFORMATION:

I. What Is the Purpose of This Document?

    The purpose of this document is to inform the public of the 
commitments made by the North Dakota Department of Health regarding 
draft modeling studies that have shown violations of the PSD increment 
for SO2 in four Class I areas. Those Class I areas include 
Theodore Roosevelt National Park and the Lostwood Wilderness Area, both 
of which are in North Dakota, and the Medicine Lakes Wilderness Area 
and the Fort Peck Class I Indian Reservation, both of which are within 
the State of Montana. In a March 13, 2001 letter to EPA, the North 
Dakota Department of Health has committed to refine this modeling 
analysis and to subsequently adopt revisions to its SIP as may be 
necessary to address the increment violations that may be shown by the 
revised modeling analysis. Specifically, the North Dakota Department of 
Health made the following commitments:
     By April 1, 2001--The State will develop an air quality 
modeling protocol.
     By January 2, 2002--The State will complete its modeling 
analysis (or within nine months from the time EPA completes its review 
of the modeling protocol).
     By February 1, 2002--The State will provide EPA with a 
summary of its modeling analysis.
     By August 1, 2003--The State will complete a SIP revision 
to resolve the increment issue (if the modeling analysis shows that the 
increment is exceeded).

Note that EPA is publishing the State's commitments in order to inform 
the public of the process that the State and EPA are following to 
address the increment violations modeled by the State. However, this 
document does not make the State's commitments legally binding.
    EPA responded to the State in a letter dated March 28, 2001. 
Specifically, EPA stated that, in light of the State's March 13, 2001 
commitment letter, we will not initiate formal action to call for a SIP 
revision to address these violations of the PSD increments for 
SO2. We acknowledged that the State needs to refine the 
modeling analysis to better determine the appropriate control 
strategy(ies) to address the violations, and we will work with the 
State in its efforts. If the State does not meet its commitments, or if 
the State and EPA cannot agree on an acceptable modeling protocol or on 
acceptable control measures, we may decide to initiate a formal SIP 
call.

II. What Are the PSD Increments?

    The purpose of the PSD program of the Clean Air Act (Act), 42 
U.S.C. 7470-7479, is to ensure that the air quality in clean air areas 
remains clean and does not deteriorate to the level of the national 
ambient air quality standards (NAAQS). The mechanism created by 
Congress to meet this goal is the establishment of ``PSD increments.'' 
These increments define the maximum allowable increases over baseline 
concentrations that are allowed in a clean air area for a particular 
pollutant. Any increase above this level indicates that significant 
deterioration of air quality has occurred. Because only emissions 
increases above the baseline concentration are considered in 
determining how much increment has been consumed, the amount of 
increment consumed can only be determined through air quality 
dispersion modeling, not through direct monitoring of ambient 
concentrations.
    The Act provides for three different classes of air quality 
protection, to reflect varying levels of protection from significant 
deterioration in air quality. In the 1977 Clean Air Act Amendments, 
Congress designated all international parks, national wilderness areas 
and national memorial parks which exceed 5000 acres in size, and all 
national parks

[[Page 29128]]

which exceed 6000 acres in size as mandatory Class I areas. Congress 
also allowed States or Tribes to request redesignation of any area to 
Class I air quality protection status. Class I areas are to receive 
special protection from degradation of air quality, and the most 
stringent PSD increments apply in these areas.
    The Class I increments for SO2 are defined in section 
163(b)(1) of the Act, 42 U.S.C. 7473(b)(1), as follows:


Annual arithmetic mean.....................  2 ug/m3
Twenty-four hour maximum...................  5 ug/m3
Three-hour maximum.........................  25ug/m3
 


    These increments are also promulgated in EPA's PSD regulations at 
40 CFR 52.21(c). North Dakota has adopted these increments as state 
regulation in section 33-15-15-01.2.b. of the North Dakota 
Administrative Code, which EPA approved as part of the SIP on November 
2, 1979 (44 FR 63102).
    For any averaging period other than an annual averaging period, 
section 163(a) of the Act allows the increment to be exceeded during 
one such period per year. Otherwise, section 163 of the Act provides 
that the increments are not to be exceeded and that the SIP must 
contain measures assuring that the increments will not be exceeded. 
Section 110(a)(2)(D)(i)(II) of the Act, 42 U.S.C. 7410(a)(2)(D)(i)(II), 
further requires the SIP to include provisions prohibiting any source 
or other emitting activity within the State from emitting air pollution 
in amounts that will interfere with measures to be included in any 
other State's implementation plan to prevent significant deterioration 
of air quality. EPA's PSD regulations also provide that the SIP must be 
revised whenever EPA or the State determines that an applicable PSD 
increment is being violated. (See 40 CFR 51.166(a)(3).)

III. How Can I Obtain More Information on This Matter?

    Copies of the State's March 13, 2001 letter and EPA's March 28, 
2001 response can be obtained from the contact person listed above. A 
Background Document is also available, which discusses in greater 
detail the PSD requirements of the Act, the history of PSD increment 
violations in North Dakota Class I areas, and the State's draft 
modeling analysis.
    This notice today informs the public and identifies the appropriate 
EPA regional office from which the public may gain further information 
and review the relevant documents pertaining to this North Dakota PSD 
increment issue.

    Dated: April 20, 2001.
Jack W. McGraw,
Acting Regional Administrator, Region VIII.
[FR Doc. 01-13409 Filed 5-25-01; 8:45 am]
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