[Federal Register Volume 62, Number 71 (Monday, April 14, 1997)]
[Rules and Regulations]
[Pages 18047-18053]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-9508]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[OR-14-1-5535; FRL-5807-4]


Approval and Promulgation of State Implementation Plans: Oregon

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: EPA is taking final action to approve a revision to the State 
Implementation Plan (SIP) submitted by the State of Oregon for the 
purpose of bringing about the attainment of the National Ambient Air 
Quality Standards (NAAQS) for particulate matter with an aerodynamic 
diameter less than or equal to a nominal 10 micrometers (PM-10). The 
implementation plan was submitted by the state to satisfy certain 
Federal requirements for an approvable moderate nonattainment area PM-
10 SIP for the Klamath Falls, Oregon, PM-10 nonattainment area.

EFFECTIVE DATE: April 14, 1997.

ADDRESSES: Copies of the state's request and other information 
supporting this action are available for inspection during normal 
business hours at the following locations: EPA, Office of Air Quality 
(OAQ-107), 1200 Sixth Avenue, Seattle, Washington 98101; EPA Oregon 
Operations Office, 811 SW Sixth Avenue, Third Floor, Portland, Oregon 
97204; and the Oregon Department of Environmental Quality, 811 SW Sixth 
Avenue, Portland, Oregon 97204-1390.

[[Page 18048]]

    Documents which are incorporated by reference are available for 
public inspection at the Air and Radiation Docket and Information 
Center, EPA, 401 M Street SW, Washington, D.C. 20460, as well as at the 
above addresses.

FOR FURTHER INFORMATION CONTACT: Rindy Ramos, EPA, Office of Air 
Quality (OAQ-107), 1200 Sixth Avenue, Seattle, Washington 98101, (206) 
553-6510.

SUPPLEMENTARY INFORMATION:

I. Background

    The area within the Klamath Falls, Oregon, Urban Growth Boundary 
(UGB), was designated nonattainment for PM-10 and classified as 
moderate under Sections 107(d)(4)(B) and 188(a) of the Clean Air Act 
(CAA), upon enactment of the Clean Air Act Amendments (CAAA) of 
1990.<SUP>1 See 56 FR 56694 (November 6, 1991) and 40 CFR 81.338. The 
air quality planning requirements for moderate PM-10 nonattainment 
areas are set out in Subparts 1 and 4 of Title I of the Act.<SUP>2 EPA 
has issued a ``General Preamble'' describing EPA's preliminary views on 
how EPA intends to review SIPs and SIP revisions submitted under Title 
I of the Act, including those state submittals containing moderate PM-
10 nonattainment area SIP requirements (see generally 57 FR 13498 
(April 16, 1992) and 57 FR 18070 (April 28, 1992)). The General 
Preamble provides a detailed discussion of EPA's interpretation of the 
Title I requirements. In this rulemaking action for the PM-10 SIP for 
the Klamath Falls nonattainment area, EPA's proposed action is 
consistent with its interpretations, discussed in the General Preamble, 
and takes into consideration the specific factual issues presented in 
the SIP. Additional information supporting EPA's action on this 
particular area is available for inspection at the addresses indicated 
above.
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    \1\ The 1990 Amendments to the Clean Air Act made significant 
changes to the Act. See Pub. L. No. 101-549, 104 Stat. 2399. 
References herein are to the Clean Air Act, as amended (``the 
Act''). The Clean Air Act is codified, as amended, in the U.S. Code 
at 42 U.S.C. 7401, et seq.
    \2\ Subpart 1 contains provisions applicable to nonattainment 
areas generally and Subpart 4 contains provisions specifically 
applicable to PM-10 nonattainment areas. At times, Subpart 1 and 
Subpart 4 overlap or may conflict. EPA has attempted to clarify the 
relationship among these provisions in the ``General Preamble'' 
document and, as appropriate, in today's notice and supporting 
information.
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    Those states containing initial moderate PM-10 nonattainment areas 
(those areas designated nonattainment under Section 107(d)(4)(B)) were 
required to submit, among other things, the following provisions by 
November 15, 1991:
    1. Provisions to assure that Reasonably Available Control Measures 
(including such reductions in emissions from existing sources in the 
area as may be obtained through the adoption, at a minimum, of 
Reasonably Available Control Technology shall be implemented no later 
than December 10, 1993;
    2. Either a demonstration (including air quality modeling) that the 
plan will provide for attainment as expeditiously as practicable but no 
later than December 31, 1994, or a demonstration that attainment by 
that date is impracticable;
    3. Quantitative milestones which are to be achieved every 3 years 
and which demonstrate Reasonable Further Progress (RFP) toward 
attainment by December 31, 1994; and
    4. Provisions to assure that the control requirements applicable to 
major stationary sources of PM-10 also apply to major stationary 
sources of PM-10 precursors except where the Administrator determines 
that such sources do not contribute significantly to PM-10 levels which 
exceed the NAAQS in the area. See Sections 172(c), 188, and 189 of the 
Act.
    States with initial moderate PM-10 nonattainment areas were 
required to: 1) submit a permit program for the construction and 
operation of new and modified major stationary sources of PM-10 by June 
30, 1992 (see Section 189(a)); and 2) submit contingency measures by 
November 15, 1993, which were to become effective without further 
action by the state or EPA, upon a determination by EPA that the area 
has failed to achieve RFP or to attain the PM-10 NAAQS by the 
applicable statutory deadline (see Section 172(c)(9) and 57 FR 13543-
13544). Oregon has made submittals in response to both of the above 
described requirements. EPA intends to address that submittal 
containing the new source review permit program in a separate action.
    To address the CAAA of 1990, Oregon submitted a PM-10 nonattainment 
area SIP for Klamath Falls, Oregon, on November 15, 1991. A subsequent 
revision to the plan was submitted to EPA on September 22, 1995. EPA 
reviewed the November 15, 1991, and September 22, 1995, SIP revisions 
according to its interpretation of subpart 1 and 4 of Part D of Title I 
of the Act. EPA concluded from its review that the SIP met the 
applicable requirements of the Act and EPA, therefore, solicited public 
comment on its proposed approval. See the June 5, 1996, Federal 
Register document at 61 FR 28531 and its accompanying Technical Support 
Document (TSD). The June 5, 1996, document also indicated that anyone 
wishing to comment should do so by July 5, 1996.
    On July 12, 1996, in response to the June 5, 1996, Federal Register 
document, EPA received comments from three parties. It is EPA's 
opinion, however, that the majority of these comments are beyond the 
scope of EPA's proposed action. Many of the comments focus on issues 
associated with a former Weyerhaeuser Company facility (currently owned 
by Collins Products LLC) located outside the designated nonattainment 
area. While the commenters raise several concerns with this facility, 
most of them do not apply to EPA's approval of the nonattainment area 
plan. As explained in more detail in the Response to Comment Document 
for this action, EPA is currently working with the State of Oregon to 
resolve issues associated with the facility.
    EPA has thoroughly considered the comments in determining the 
appropriate action on the Klamath Falls PM-10 Control Plan. A summary 
of EPA's review of the comments is presented in the ``Response to 
Comments'' section below. A more detailed Response to Comment Document 
is available for public review at the above addresses.
    EPA is approving the Klamath Falls SIP as described in the June 5, 
1996, Federal Register document at 61 FR 28531 and its accompanying 
(TSD). The following is a review of those comments received during the 
public comment period.

II. Response to Comments

A. Area Designation

    The commenters all stated that the boundary for the nonattainment 
area should be enlarged to include sources currently external to the 
Urban Growth Boundary (UGB). One group of commenters provided the 
following:

    NAAQS standards were the original keystone of the CAA. All 
``areas'' \2\ containing a site for which air quality data show a 
violation of NAAQS were originally designated as non-attainment by 
Congress. Sec. 107(d)(4)(B)(2) [sic]. Klamath Falls was classified 
as a moderate PM-10 non-attainment area by operation of law.

________________

    \2\ Congress' use of the word area does not mean nonattainment 
area. The use of the word ``area'' must be given its plain meaning. 
The definition of ``area'' is not found in the act. When referring 
to non-attainment area, the act is using the definition found at 
Sec. 171(2). The word area cannot logically

[[Page 18049]]

mean non-attainment area. This would be circular.

    These same commenters contend that ``the urban growth boundary is 
an arbitrary land classification distinction.'' The comment states: 
``The 1986 modeling fails to satisfy 40 CFR part 51, appendix W. The 
SIP modeling should have included a `land use classification procedure 
or a population based procedure to determine whether the character' of 
the area was primarily urban or rural.''
    The first comment implies that Klamath Falls was designated 
nonattainment for PM-10 in accordance with section 107(d)(4)(B)(ii) of 
the Clean Air Act (CAA). This is not entirely correct. Klamath Falls 
was designated nonattainment in accordance with section 
107(d)(4)(B)(i). This section of the CAA states:

    (i) each area identified in 52 Federal Register 29383 (Aug. 7, 
1987) as a Group 1 area (except to the extent that such 
identification was modified by the Administrator before November 15, 
1990) is designated nonattainment for PM-10.

    EPA believes it is important to point out that the Klamath Falls 
nonattainment boundaries were established, as were the boundaries for 
all the initial PM-10 nonattainment areas, through a public notice 
process which provided an opportunity for comment on the 
appropriateness of the boundary description. In the August 7, 1987, 
Federal Register document, Klamath Falls was identified by EPA as a PM-
10 area of concern and categorized as a Group 1 area. EPA did not 
receive any comments questioning this action. Subsequently, on October 
31, 1990, the area of concern was further defined as the area within 
the urban growth boundary. See 55 FR 45799. Therefore, upon passage of 
the Clean Air Act Amendments on November 15, 1990, the existing Klamath 
Falls Group 1 area, as defined by the urban growth boundary, was 
designated nonattainment and classified as a moderate PM-10 
nonattainment area by operation of law. See 56 FR 56694 at 56705-56706, 
56820 (Nov. 6, 1991) (document announcing formal codification of 
initial PM-10 nonattainment areas in 40 CFR part 81).
    On March 15, 1991 (56 FR 11101), prior to the November 6, 1991, 
formal codification document, EPA announced all the designations and 
classifications occurring for PM-10 by operation of law upon enactment 
of the Clean Air Act (the ``initial PM-10 nonattainment areas''). In 
this Federal Register document EPA provided, among other things, an 
opportunity for the public to comment on EPA's announcement. EPA 
requested public comment on the announcement in order to facilitate 
public participation and avoid errors. EPA did not receive any comments 
disputing the extent and description (i.e., the boundary) of the 
Klamath Falls nonattainment area.
    Furthermore, Oregon Administrative Rule (OAR) 340-31-500(10) 
contains a legal description of the Klamath Falls UGB. This rule is 
part of the federally-approved SIP.
    EPA is not sure what distinction the commenter is attempting to 
draw in the context of section 107(d) between the word ``area'' and the 
phrase ``nonattainment area.'' That section itself defines a 
nonattainment area as, among other things, any area that does not meet, 
i.e., is violating, the national ambient air quality standard for any 
pollutant. Section 107(d)(1)(A)(i). Other provisions in section 107(d) 
determine the process by which particular areas are officially 
designated as nonattainment. Indeed, the definition in section 171(2) 
essentially refers back to the section 107(d) definition.
    The comment on the urban vs. rural land use classification in 
section 8.2.8 of EPA's Guideline on Air Quality Models (Revised) is not 
relevant either to issues regarding the determination of the 
appropriate boundaries of the nonattainment area, or the method of 
modeling used to demonstrate attainment. Receptor, not dispersion 
modeling, is used to demonstrate attainment with the NAAQS. Section 
8.2.8 was written primarily in the context of the Prevention of 
Significant Deterioration program. It was written to determine the 
dispersion coefficient when modeling a single source and not for the 
purpose of determining the nonattainment boundaries of an area.

B. Weyerhaeuser (Collins Products LLC) Issues

    The primary issues associated with the Weyerhaeuser facility 
presented by a commenter include, but are not limited to: (1) 
dispersion modeling showing significant impacts at the Peterson School 
monitoring site, (2) dispersion modeling showing exceedances of the 24-
hour NAAQS outside of the UGB, and (3) exclusion of Weyerhaeuser's PM-
10 emissions from the plan's emission inventory. Each of these issues 
is addressed generally below and in more detail in the Response to 
Comment document.
1. Weyerhaeuser's Modeled Impacts at Peterson School
    One commenter refers to two modeling analyses, one conducted in 
1992 and one conducted in 1994, which indicated the facility had a 
significant impact at Peterson School and its emissions contributed to 
an exceedance of the NAAQS at an unmonitored location. Another modeling 
analysis, not referenced by the commenter, was conducted in 1995.
    The 1992 and 1994 modeling analyses performed to assess 
Weyerhaeuser's impact at the Peterson School monitoring site have been 
superseded by a modeling analysis conducted in 1995. The modeling 
analysis in 1995 was performed to satisfy the SIP commitment that 
Weyerhaeuser's emissions be dispersion modeled ``to determine whether 
emissions from the Weyerhaeuser facility have a significant impact 
(annual average impact of 1 <greek-m>g/m<SUP>3, or 24-hour impact of 5 
<greek-m>g/m<SUP>3) at the maximum concentration point within the 
nonattainment area (Peterson School monitoring site).'' <SUP>3 The 1995 
analysis was also performed to address deficiencies with the 1992 and 
1994 analyses. Therefore, because the 1992 and the 1994 modeling 
analyses have been superseded, the comments received concerning the 
1992 and the 1994 modeling analyses performed by either Weyerhaeuser or 
by the Oregon Department of Environmental Quality (ODEQ) are no longer 
relevant.
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    \3\ State Implementation Plan for PM-10 in Klamath Falls, 
October 1991, Section 4.12.3.2.
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    The 1995 analysis, summarized in an ODEQ August 4, 1995, 
memorandum, indicates that, on exceedance days, the Weyerhaeuser 
facility does not have a significant impact at the Peterson School 
monitoring site. Included in this analysis is the facility's current 
permitted allowable emissions, emission credits, and plant fugitive 
emissions. These allowable emissions are reflected in the facility's 
Air Contaminant Discharge Permit, issued on November 20, 1995. Through 
the state's operating permit program, this permit is part of the 
federally approved SIP.
    This 1995 analysis indicates that the facility's current permitted 
emissions do not have a significant impact on the Peterson School site 
during exceedance days.
2. Weyerhaeuser's Modeled Impact at an Unmonitored Location
    One commenter contends:

that there are presently exceedances within the Klamath area which 
may preclude redesignation. Sec. 172(c)(1) provides that an 
approvable SIP ``shall provide for the attainment of the national 
primary ambient air quality standards.''


[[Page 18050]]


    EPA believes that the comment alludes to a modeled violation of the 
NAAQS at a location outside of the designated nonattainment area 
boundary. Specifically, preliminary dispersion modeling information 
indicates that the Weyerhaeuser Klamath Falls facility is causing a 
violation of the NAAQS at an unmonitored site outside the nonattainment 
area. The modeled violation of the NAAQS outside of the nonattainment 
area and the approvability of the Klamath Falls PM-10 Control Plan by 
EPA, are two separate issues. This rulemaking action concerns only the 
latter issue.
    Nevertheless, to address the comment concerning the modeled 
violation, it is useful to note that the State of Oregon, with input 
from EPA, is currently working with Collins Products LLC to mitigate 
the modeled NAAQS violation. Further, as discussed in the June 5, 1996, 
Federal Register document (61 FR 28531) and the TSD for that notice, 
any violation of the NAAQS outside of an existing nonattainment area 
would be subject to its own planning requirements, analysis, and 
potential control measures.
3. Exclusion of Emissions
    Both the 1991 version and the 1995 revision of the proposed Klamath 
Falls PM-10 SIP, to some degree, discuss Weyerhaeuser's emissions. As 
required by the nonattainment area plan, and as discussed in the TSD to 
the June 5, 1996, Federal Register document; the Response to Comments 
Document for this action; and elsewhere in this document, Weyerhaeuser 
evaluated its impact at the Peterson School monitoring site.

C. Slash Burning Emissions

    EPA received comments from two commenters indicating that PM-10 
emissions from slash burning are not properly quantified. One of the 
commenters contends that:

    DEQ's emission inventory for Klamath County tallies slash 
burning as the single largest source of emissions

and, given that, wonders how EPA can

    * * * support a plan that considers slash to be a 0% contributor 
when DEQ's own records show that over 3,000 \4\ tpy come from slash.

________________

    \4\ This figure is from 1987-88 using DEQ's emission factor 
applied to State Forestry Smoke Management Annual Report data.

    As the commenter indicates, these emission estimates are on a 
county-wide basis and as such do not accurately reflect emissions 
generated from within the nonattainment area or the area in close 
proximity to the nonattainment area. For comparison purposes, the 
county is 6,135 square miles, whereas the nonattainment area is only 
approximately 70 square miles. In addition, specific information 
linking slash burning days with monitored exceedance days is not 
presented.
    However, to address the potential impacts of forestry slash 
burning, a voluntary smoke management plan was developed and 
implemented. This plan establishes a Special Protection Zone (SPZ) 
around the nonattainment area. This SPZ restricts prescribed burning 
within a 20 miles radius of Klamath Falls during the winter residential 
wood burning season. As previously stated, exceedances of the 24-hour 
NAAQS have historically occurred during the wood burning season. To 
supplement the voluntary smoke management plan, a Memorandum of 
Understanding was signed by and between several timber companies, 
several national forests, the Oregon Department of Forestry, and the 
Bureau of Land Management. As discussed in the June 5, 1996, Federal 
Register document and its TSD, EPA believes these steps adequately 
address the potential impacts of slash burning on the nonattainment 
area.

D. Control Measures

    It is one commenter's position that * * * reduction in emissions do 
not `result from' implementation of the plan. Sec. 107(d)(3)(E)(iii).''
1. Mandatory Residential Woodburning Curtailment Program
    It is one commenter's belief that a lack of exceedances of the 24-
hour NAAQS since January 1991, is

    * * * not a measure of the success of the mandatory woodstove 
curtailment program, but rather the accumulation of a number of 
significant changes that have been occurring. The most significant 
changes occurred at Weyco [Weyerhaeuser] * * *

    Because the mandatory curtailment program (a voluntary program had 
been in place for several years) was implemented November 1, 1991, it 
is this commenter's opinion that the first complete year where 
reductions from the mandatory program would have occurred is in 1992.
    It is EPA's opinion that the chosen control strategies, which 
include the mandatory curtailment program, have brought the area into 
attainment with the NAAQS. This is discussed in more detail in the June 
5, 1996, Federal Register document, the TSD to that document, and the 
Response to Comment Document for this document.
    Based on ambient monitoring, the last seven exceedances of the 24-
hour NAAQS occurred in 1991. All of the exceedances occurred in January 
of that year. On October 31, 1991, one day before the mandatory 
curtailment program was implemented, a monitored value of 136 
<greek-m>g/m\3\ was recorded. On November 1, 1991, the mandatory 
curtailment program was implemented, and, during the 1991/1992 
woodburning season, the highest monitored value was 133 <greek-m>g/
m\3\. During November and December of 1991, there were no monitored 
exceedances of the 24-hour NAAQS, thus, indicating that emission 
reductions were being achieved by the end of 1991. In mid-1992, 
Weyerhaeuser's five hog fuel boilers were taken out of service. This is 
after completion of a successful woodburning season (November 1991 
through February 1992) without any exceedances of the NAAQS. Therefore, 
it is not unreasonable for EPA to believe that improvement in air 
quality is due to implementation of the control measures. As discussed 
in the TSD to the June 5, 1996, Federal Register document, ODEQ has 
conducted compliance surveys and documented the effectiveness of the 
program.
    However, EPA also recognizes that the Weyerhaeuser facility has 
reduced its actual PM-10 emissions and has taken a reduction in its 
allowable emissions of over 600 tons since 1992. The facility is 
currently permitted at 111 pounds per hour, a substantial reduction 
from its previous limit.
2. Open Burning
    The nonattainment area plan does not request credit for its open 
burning control measures. It is one commenter's opinion that this is 
not appropriate because significant open burning emissions existed in 
the baseline period.
    It is the state's prerogative to request credit for a specific 
control measure. In regard to open burning, the plan does contain open 
burning restrictions, but ODEQ chose not to request emission reduction 
credits for the reductions resulting from the open burning control 
measure. Nevertheless, emission reductions from the plan's control 
measures will be realized and remain enforceable.

E. Attainment Demonstration Method

    ODEQ conducted an attainment demonstration based upon receptor 
modeling proportional roll-back calculations to estimate the emission 
reductions required in 1994 to achieve the NAAQS. One commenter does 
not agree with this method and states: ``The SIP ignores the results of 
the dispersion

[[Page 18051]]

model [1992 modeling], uses an inappropriate rollback model with faulty 
emission inputs and attempts to use a receptor model for validation.'' 
The commenter further states the SIP violates the CAA because two 
documents contained in Section 3.2 of 40 CFR Part 51, Appendix W, were 
not used to justify the use of rollback.
    The same commenter provided a chart (Attachment D) relating ``total 
wood production at Weyerhaeuser and PM-10 readings at Peterson School'' 
and states that the correlation coefficient (R square value) is 0.94 
using linear regression in an attempt to demonstrate that Weyerhaeuser 
was a dominant contributor to exceedances at Peterson School.
    As noted elsewhere, the 1992 modeling analysis has been superseded 
by a modeling analysis conducted in 1995 and, therefore, the 1992 
analysis is no longer relevant.
    As previously stated, the initial moderate PM-10 nonattainment 
areas were required to submit a demonstration (including air quality 
modeling) showing that the plan would provide for attainment as 
expeditiously as practicable but no later than December 31, 1994 (see 
Section 189(a)(1)(B) of the Act). The General Preamble sets out EPA's 
guidance on the use of modeling for moderate area attainment 
demonstrations (see 57 FR 13539). Alternatively, the state had to show 
attainment by December 31, 1994, or that attainment was impracticable.
    Generally, EPA recommends that attainment be demonstrated according 
to the PM-10 SIP Development Guideline (June 1987), which presents 
three methods. Federal regulations require demonstration of attainment 
``by means of a proportional model or dispersion model or other 
procedure which is shown to be adequate and appropriate for such 
purposes'' (40 CFR 51.112). The preferred method is the use of both 
dispersion and receptor modeling in combination. The regulation and the 
guideline also allow the use of dispersion modeling alone, or the use 
of two receptor models in combination with proportional rollback.
    As indicated in the General Preamble, 57 FR at 13539, EPA has 
developed a supplemental attainment demonstration policy for initial 
PM-10 nonattainment areas such as Klamath Falls. The Preamble provides 
additional flexibility in meeting the PM-10 attainment demonstration 
requirements. An earlier April 2, 1991, memorandum titled, ``PM-10 
Moderate Area SIP Guidance: Final Staff Work Product,'' contained 
``Attachment 5'' describing the same policy. The policy explains that 
in certain circumstances a modified attainment demonstration may be 
appropriate on a case-by-case basis. It may be reasonable to accept a 
modified attainment demonstration in cases where ``time constraints, 
inadequate resources, inadequate data bases, lack of a model for some 
unique situations, and other unavoidable circumstances would leave an 
area unable to submit an attainment demonstration'' by November 15, 
1991. The policy further explains that its application is reserved for 
those initial PM-10 nonattainment areas that have ``completed the 
technical analysis * * * and made a good-faith effort to submit a final 
SIP by their November 15, 1991, due date.''
    During development of the Klamath Falls initial moderate area PM-10 
attainment plan, ODEQ did not use dispersion modeling to estimate the 
design values or in the attainment and maintenance demonstrations. This 
was due to: (1) the lack of adequate historical meteorological data, 
(2) the late receipt in the development process of spatially resolved 
emission inventory data needed for modeling, (3) the fact that the 
intense and extremely shallow inversions and calm winds in the area 
(typical wind speeds during exceedances days are less than one meter 
per second) are not conducive to dispersion modeling (EPA does not have 
and has not developed an approved guideline model for conditions of 
this type), and (4) the fact that on winter days, when worst case air 
quality conditions occur, the airshed is heavily dominated by emissions 
from woodstoves, fireplaces, and road sanding.
    The Klamath Falls PM-10 attainment demonstration is based upon 
receptor modeling proportional roll-back calculations to estimate the 
emission reductions required in 1994 to achieve the NAAQS. Emission 
inventory estimates were reconciled with Chemical Mass Balance (CMB--
version 7.0) receptor modeling. Results from two emission estimation 
methods--emission inventory and receptor modeling--are in agreement 
that woodsmoke and soil dust are the major sources of emissions on 
exceedance days. According to the emission inventory, woodsmoke equals 
80% and soil dust equals 8% of total PM-10 particulate. According to 
the CMB analysis, woodsmoke equals 82% and soil dust equals 10.9% of 
particulate. This issue is discussed in more detail in the TSD for the 
June 5, 1996, Federal Register document (see 61 FR 28537).
    EPA guidance on CMB modeling specifies that the apportionment 
should account for at least 80% of the measured aerosol mass. ODEQ's 
analysis accounted for 96% of the mass.
    The comment that the two documents (Interim Procedures for 
Evaluating Air Quality Models and Protocol for Determining the Best 
Performing Model) contained in Section 3.2 of 40 CFR part 51, appendix 
W are not used to justify the use of roll-back is correct. This is 
because the documents are intended to be used to evaluate the 
performance of dispersion models not receptor models.
    Because the input data for the graph presented in Attachment D were 
not provided, EPA was not able to verify the correlation. In addition, 
the graph presented in Attachment D, entitled ``ANNUAL PM10 VS WEYCO 
LUMBER PRODUCTION'', shows lumber production (board feet  x  100,000) 
on the Y axis, and annual PM-10 concentrations (<greek-m>g/m\3\) on the 
X axis. The labeling of the X and Y axes appear to be in error. For 
example the graph indicates that, when lumber production is 
approximately 70  x  100,000 board feet, annual PM-10 concentrations 
should be approximately 200 <greek-m>g/m\3\. This value appears to be 
in error because monitored annual PM-10 concentrations have never been 
above 73 <greek-m>g/m\3\. Furthermore, the graph does not consider 
implementation of the area's control measures (e.g., woodsmoke 
curtailment, road dust measures, woodstove changeout), which 
significantly reduced emissions over the same time period covered by 
the graph, and the resulting improvement in air quality due to 
implementation of the selected control measures.
    Therefore, it is EPA's opinion that the graph presented in 
Attachment D is inconclusive evidence that Weyerhaeuser was (is) a 
dominant contributor to exceedances at Peterson School. In conclusion, 
because ODEQ followed EPA guidance, used the approved EPA chemical mass 
balance model, and because the CMB results were verified by the 
emission inventory, EPA is satisfied that the source apportionment 
provided by ODEQ in the Klamath Falls SIP is adequate.
    EPA believes this conclusion is strengthened by the fact that, 
since implementation of the control strategies in 1991, the area has 
not exceeded the PM-10 NAAQS and has, based on monitored values, met 
the CAA attainment date of December 31, 1994.

F. Contingency Measures

    It is one commenter's opinion that the SIP's contingency plan ``is 
flawed,'' ``the contingency section of the CAA has been violated,'' and 
the measures do not ``protect against backsliding.'' These comments are 
made in regard to the

[[Page 18052]]

plan's contingency measure applicable to the Weyerhaeuser facility.
    EPA disagrees that the contingency section of the CAA has been 
violated. All moderate area SIPs, due November 15, 1991, were required 
to contain contingency measures that would be immediately implemented 
upon a determination by EPA that an area failed to make RFP or to 
attain the standard by the applicable attainment date. Besides a 
contingency measure applicable to the Weyerhaeuser facility (see OAR 
340-21-200), the nonattainment area plan also contains contingency 
measures applicable to woodstoves, industrial sources located inside 
the nonattainment area, and numerous road dust control measures. These 
measures were reviewed and discussed in detail in the TSD for the June 
5, 1996, Federal Register document. The attainment date for the Klamath 
Falls nonattainment area was December 31, 1994. Based on monitored air 
quality data, the Klamath Falls PM-10 nonattainment area has 
demonstrated RFP and attained the PM-10 NAAQS. Air quality monitors 
located within the designated nonattainment area boundary have not 
recorded an exceedance of the NAAQS since 1991.
    In light of all the above, EPA believes the Klamath Falls SIP does 
provide for ``meaningful contingency planning'' that meets the 
requirements of the Act.

III. This Action

    Section 110(k) of the Act sets out provisions governing EPA's 
review of SIP submittals (see 57 FR 13565-13566). In this action, EPA 
is approving the plan revisions submitted to EPA on November 15, 1991, 
and September 22, 1995. EPA has determined that the submittals meet all 
of the applicable requirements of the Act due on November 15, 1991, 
with respect to moderate area PM-10 submittals. Also, EPA is granting 
the exclusion from PM-10 control requirements applicable to major 
stationary sources of PM-10 precursors. In addition, EPA is approving 
the SIP revision submitted on November 15, 1991, as meeting the 
requirement for contingency measures.
    Nothing in this action should be construed as permitting or 
allowing or establishing a precedent for any future request for 
revision to any SIP. Each request for revision to the SIP shall be 
considered separately in light of specific technical, economic, and 
environmental factors, and in relation to relevant statutory and 
regulatory requirements.

IV. Effective Date

    Pursuant to Section 553(d)(3) of the Administrative Procedures Act 
(APA), this final rule is effective April 14, 1997. Section 553(d)(3) 
of the APA allows EPA to waive the requirement that a rule be published 
30 days before the effective date if EPA determines there is ``good 
cause'' and publishes the grounds for such a finding with the rule. 
Under section 553(d)(3), EPA must balance the necessity for immediate 
federal enforceability of these SIP revisions against principles of 
fundamental fairness which require that all affected persons be 
afforded a reasonable time to prepare for the effective date of a new 
rule. United States v. Gavrilovic, 551 F 2d 1099, 1105 (8th Cir. 1977). 
The purpose of the requirement for a rule to be published 30 days 
before the effective date of the rule is to give all affected persons a 
reasonable time to prepare for the effective date of a new rule. Id.
    EPA has determined good cause exists to make this Federal Register 
document effective upon publication. The rules made federally 
enforceable by this Federal Register document have been enforceable as 
a matter of state law for more than five years. In addition, the PM-10 
emission inventory contained in the Klamath Falls PM-10 Control Plan 
must be federally approved before the Oregon Department of 
Transportation can make conformity determinations for several 
transportation projects in Klamath Falls which will benefit the general 
public. The imposition of the 30-day delay in the effective date of 
this SIP revision would require some of these projects to be postponed 
for an additional 30 days. Therefore, EPA believes the 30-day 
publication period would cause undue burdens to the public, and to 
affected governmental and transportation planning agencies.
    Thus, EPA has determined that good cause exists to make these SIP 
revisions immediately effective and that the principles of fundamental 
fairness are met because all known affected persons have been afforded 
a reasonable time to prepare for the effective date of these SIP 
revisions. Accordingly, pursuant to section 553(d)(3) of the APA, this 
Oregon SIP revision approval is effective upon publication in the 
Federal Register.

VI. Administrative Requirements

A. Executive Order 12866

    This action has been classified as a Table 3 action for signature 
by the Regional Administrator under the procedures published in the 
Federal Register on January 19, 1989 (54 FR 2214-2225), as revised by a 
July 10, 1995, memorandum from Mary Nichols, Assistant Administrator 
for Air and Radiation. The Office of Management and Budget (OMB) has 
exempted this regulatory action from E.O. 12866 review.

B. Regulatory Flexibility Act

    Under the Regulatory Flexibility Act, 5 U.S.C. 600 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 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.
    SIP approvals under section 110 and subchapter I, part D, of the 
Clean Air Act do not create any new requirements but simply approve 
requirements that the state is already imposing. Therefore, because the 
Federal SIP approval does not impose any new requirements, I certify 
that it does not have a significant impact on any small entities 
affected. Moreover, due to the nature of the Federal-state relationship 
under the CAA, preparation of a flexibility analysis would constitute 
Federal inquiry into the economic reasonableness of state action. The 
Clean Air Act forbids EPA to base its actions concerning SIPs on such 
grounds. Union Electric Co. v. U.S. EPA, 427 U.S. 246, 255-66 (1976); 
42 U.S.C. 7410(a)(2).

C. Unfunded Mandates

    Under Section 202 of the Unfunded Mandates Reform Act of 1995 
(``Unfunded Mandates Act''), signed into law on March 22, 1995, EPA 
must prepare a budgetary impact statement to accompany any proposed or 
final rule that includes a Federal mandate that may result in estimated 
costs to state, local, or tribal governments in the aggregate; or to 
the private sector, of $100 million or more. Under Section 205, EPA 
must select the most cost-effective and least burdensome alternative 
that achieves the objectives of the rule and is consistent with 
statutory requirements. Section 203 requires EPA to establish a plan 
for informing and advising any small governments that may be 
significantly or uniquely impacted on by the rule.
    EPA has determined that the approval action does not include a 
Federal mandate that may result in estimated costs of $100 million or 
more to either state, local, or tribal governments in the aggregate, or 
to the private sector. This Federal action approves pre-existing 
requirements under state or local law, and imposes no new requirements.

[[Page 18053]]

Accordingly, no additional costs to state, local, or tribal 
governments, or to the private sector, result from this action.

D. Submission to Congress and the General Accounting Office

    Under 5 U.S.C. 801(a)(1)(A) as added by the Small Business 
Regulatory Enforcement Fairness Act of 1996, EPA submitted 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 
General Accounting Office prior to publication of the rule in today's 
Federal Register. This rule is not a ``major rule'' as defined by 5 
U.S.C. 804(2).

E. 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 June 13, 1997. 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 CAA section 307(b)(2), 42 U.S.C. 
7607(b)(2))

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by 
reference, Particulate matter.

    Note: Incorporation by reference of the Implementation Plan for 
the State of Oregon was approved by the Director of the Office of 
Federal Register on July 1, 1982.

    Dated: March 28, 1997.
Chuck Clarke,
Regional Administrator.

    Part 52, chapter I, title 40 of the Code of Federal Regulations is 
amended as follows:

PART 52--[AMENDED]

    1. The authority citation for Part 52 continues to read as follows:

    Authority: 42 U.S.C. 7401-7671q.

Subpart MM--Oregon

    2. Section 52.1970 is amended by adding paragraph (c)(119) to read 
as follows:


Sec. 52.1970  Identification of plan.

* * * * *
    (c) * * *
    (119) November 15, 1991, and September 20, 1995, letters from the 
Director, Oregon Department of Environmental Quality, to the Region 10 
Regional Administrator, EPA, submitting the PM-10 Klamath Falls, 
Oregon, PM-10 Control Plan and amendments as revisions to its SIP.
    (i) Incorporation by reference.
    (A) State Implementation Plan for PM-10 in Klamath Falls, dated 
October 1991 and revised August 1995; and Appendix 4: Ordinances and 
Commitments, Ordinance No. 6630 (adopted September 16, 1991), and 
Ordinance No. 63 (adopted July 31, 1991)--Chapters 170 and 406.

[FR Doc. 97-9508 Filed 4-11-97; 8:45 am]
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