Clean Air Act Reclassification; Arizona-Phoenix Nonattainment Area; PMINF10

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 81

[AZR91-0003; FRL-5503-7]

Clean Air Act Reclassification; Arizona-Phoenix Nonattainment

Area; PM10

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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[[Page 21373]]

SUMMARY: In this document EPA is making a final finding that the

Phoenix Planning Area (PPA) has not attained the PM10 (particulate

matter 10 microns or less in aerodynamic diameter) national ambient air

quality standards (NAAQS) by the applicable attainment date in the

Clean Air Act (CAA) for moderate PM10 nonattainment areas,

December 31, 1994. This finding is based on EPA's review of PM10

ambient air quality data. As a result of this finding, the PPA is

reclassified as a serious PM10 nonattainment area by operation of

law. The intended effect of the reclassification is to allow the State

18 months from the effective date of this action to submit a new State

Implementation Plan (SIP) demonstrating attainment of the PM10

NAAQS by December 31, 2001, the CAA attainment date for serious areas.

EFFECTIVE DATE: This action is effective on June 10, 1996.

FOR FURTHER INFORMATION CONTACT: Wallace Woo, Chief, Plans Development

Section (A-2-2), Air Planning Branch, Air and Toxics Division, U.S.

Environmental Protection Agency, Region 9, 75 Hawthorne Street, San

Francisco, California 94105, (415) 744-1207.

SUPPLEMENTARY INFORMATION:

I. Background

A. CAA Requirements and EPA Actions Concerning Designation and

Classification

On November 15, 1990, the date of enactment of the 1990 Clean Air

Act Amendments (CAA), PM10 areas meeting the qualifications of

section 107(d)(4)(B) of the Act were designated nonattainment by

operation of law. Once an area is designated nonattainment, section 188

of the Act outlines the process for classification of the area and

establishes the area's attainment date. Pursuant to section 188(a), all

PM10 nonattainment areas were initially classified as moderate by

operation of law upon designation as nonattainment. These nonattainment

designations and moderate area classifications were codified in 40 CFR

part 81 in a Federal Register notice published on November 6, 1991 (56

FR 56694).

Under section 188(c)(1) of the CAA, the attainment deadline for all

PM10 nonattainment areas originally classified as moderate was no

later than December 31, 1994. Under section 188(d), EPA may, upon

application by a state, extend the attainment deadline if the state has

complied with all requirements and commitments pertaining to the area

in the applicable implementation plan. In addition, in order to qualify

for an extension there must have been no more than one exceedance of

the 24 hour national ambient air quality standard (NAAQS) in the area

in the year preceding the extension year, and the annual mean

concentration of PM10 in the area for such year must be less than

or equal to the standard. Under this provision, EPA may grant up to two

one year extensions if these conditions have been met.

B. Reclassification as Serious Nonattainment

EPA has the responsibility, pursuant to sections 179(c) and

188(b)(2) of the CAA, of determining within six months of the

applicable attainment date, whether PM10 nonattainment areas have

attained the NAAQS. Section 179(c)(1) of the Act provides that these

determinations are to be based upon an area's air quality as of the

attainment date, and section 188(b)(2) is consistent with this

requirement. EPA makes the determinations of whether an area's air

quality is meeting the PM10 NAAQS based upon air quality data

gathered at monitoring sites in the nonattainment area and entered into

the Aerometric Information Retrieval System (AIRS). These data are

reviewed to determine the area's air quality status in accordance with

EPA guidance at 40 CFR part 50, Appendix K.

Pursuant to Appendix K, attainment of the annual PM10 standard

is achieved when the annual arithmetic mean PM10 concentration is

equal to or less than 50 g/m\3\. The annual average is

determined by first calculating the average PM10 concentration for

each calendar quarter. The annual average is then calculated by

averaging the four calendar quarter averages. Attainment of the 24 hour

standard is determined by calculating the expected number of

exceedances of the 150 g/m\3\ limit per year. The 24 hour

standard is attained when the expected number of exceedances is 1.0 or

less. A total of three consecutive years of clean air quality data is

generally necessary to show attainment of the 24 hour and annual

standards for PM10. A complete year of air quality data, as

referred to in 40 CFR part 50, Appendix K, is comprised of all four

calendar quarters with each quarter containing data from at least 75

percent of the scheduled sampling days.

Under section 188(b)(2)(A) of the CAA, a moderate PM10

nonattainment area must be reclassified as serious by operation of law

after the statutory attainment date if the Administrator finds that the

area has failed to attain the NAAQS. Pursuant to section 188(b)(2)(B),

EPA must publish a notice in the Federal Register identifying those

areas that failed to attain the standard and the resulting

reclassification.

C. Effect of Reclassification

PM10 nonattainment areas reclassified as serious under section

188(b)(2) of the CAA are required to submit, within 18 months of the

area's reclassification, SIP revisions providing for the implementation

of best available control measures (BACM) no later than four years from

the date of reclassification. The SIP also must contain a demonstration

that the implementation of BACM will provide for attainment of the

PM10 NAAQS no later than December 31, 2001. EPA has provided

specific guidance on developing serious area PM10 SIP revisions in

an addendum to the General Preamble to Title I of the Clean Air Act.

See 59 FR 41998 (August 16, 1994).

D. Proposed Finding of Failure to Attain

On June 7, 1995 EPA proposed to find that the Phoenix Planning Area

(PPA) had failed to attain the PM10 NAAQS by the applicable

attainment date. 60 FR 30046. This proposed finding was based on

PM10 monitoring data collected by Maricopa County during the years

1992 through 1994. The air quality monitoring data for the PPA showed

three violations of the 24 hour PM10 NAAQS in 1992 and violations

of the annual PM10 NAAQS in 1992 and 1993. The air quality

monitoring data are discussed in detail in the Notice of Proposed

Rulemaking (NPRM). 60 FR 30046, 30047. The following table summarizes

the data on which EPA has based its finding of failure to attain:

----------------------------------------------------------------------------------------------------------------

24 hour exceedances Annual exceedances

Site ----------------------------------------------------------------------------------

Conc. Date 1992 1993

----------------------------------------------------------------------------------------------------------------

4732 S. Central, Phoenix..... 171 g/m\3\ 11/20/92 .................... ....................

158 g/m\3\ 12/2/92 .................... ....................

1475 E. Pecos, Chandler...... 156 g/m\3\ 11/20/92 56 g/m\3\ 58 g/m\3\

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[[Page 21374]]

On October 20, 1995, the State requested, under section 188(d) of

the CAA, that EPA extend the attainment deadline for the PPA from

December 31, 1994 to December 31, 1995. This request was based on the

lack of recorded exceedances of the PM10 NAAQS in 1994. In 1995,

however, the PPA recorded two exceedances of the 24 hour NAAQS. On June

28, 1995 a concentration of 160 g/m\3\ was recorded at the

Chandler monitoring site, and on July 30, 1995 a concentration of 252

g/m\3\ was recorded, also at the Chandler monitoring site.

Additionally, the annual average concentration at the Chandler site in

1995 was 57.9 g/m\3\. Thus, while the State technically

qualified for a one year attainment date extension, the 1995 violations

effectively moot this request because the area cannot qualify for a

second extension. Therefore, EPA does not intend to act on the State's

extension request.

II. Response to Comments on Proposed Finding

During the public comment period on EPA's proposed finding, the

Agency received comment letters from: one State legislator; the Arizona

Department of Environmental Quality (ADEQ); the Arizona Department of

Transportation (ADOT); the Arizona Motor Transport Association; the

Maricopa Association of Governments (MAG); and the Maricopa County

Board of Supervisors. The issues raised in these comment letters are

summarized below and are followed by EPA's responses.

A. Economic Impacts of EPA's Finding

Comment: EPA's determination in the proposed rulemaking that a

finding of failure to attain the PM10 standard is not subject to

certain requirements in Executive Order (E.O.) 12866 or the Unfunded

Mandates Reform Act is incorrect, as is EPA's certification that this

action does not have a significant impact on small entities.

Response: 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 E.O. The E.O.

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.''

Sections 202, 203 and 205 of the Unfunded Mandates Reform Act of

1995 (Unfunded Mandates Act), 2 U.S.C. Secs. 1501-1571, requires EPA to

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.

Under the Regulatory Flexibility Act, 5 U.S.C. Sec. 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 Secs. 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.

Under section 188(b)(2) of the CAA, EPA findings of failure to

attain are based upon air quality considerations, and reclassification

of nonattainment areas must occur by operation of law in light of

certain air quality conditions. Such findings and reclassification do

not, in-and-of-themselves, impose any new requirements on any sectors

of the economy. In addition, because the statutory requirements for the

differently classified areas are clearly defined, and because those

requirements are automatically triggered by classifications that, in

turn, are triggered by air quality values, findings of failure to

attain and reclassification cannot be said to impose a materially

adverse impact on State, local, or tribal governments or communities.

This conclusion does not in any way reflect a determination

regarding estimated or actual impacts of a reclassification on

Arizona's economy. It is important to understand that the sole

regulatory action that EPA is taking under the CAA involves only a

factual finding of whether the Phoenix area attained the PM10

standards by December 31, 1994, the statutory attainment date for

moderate areas. If EPA finds that the area has failed to attain by the

deadline, then the area is reclassified as serious, not by EPA, but by

operation of law. A finding by EPA that an area has failed to timely

attain the PM10 standards is based on air quality monitoring data

collected by Maricopa County and ADEQ from 1992 through 1994. The

statute does not require any action on EPA's part, since the CAA

specifies automatic reclassification of an area as a result of a

finding that the area has not attained the PM-10 standards. See section

188(b)(2). Because EPA's role in making such a finding is essentially

ministerial, the Agency has concluded that it does not impose any new

requirements or mandates on any sector of the State economy.

For the above reasons, EPA has determined that the finding of

failure to attain being made today would result in none of the effects

identified in section 3(f) of E.O. 12866 and is therefore not a

significant regulatory action, as defined in the E.O. Similarly, EPA

has concluded that the finding of failure to attain does not constitute

a Federal mandate within the meaning of the Unfunded Mandates Act.

Furthermore, the Agency has certified that the redesignation of the

attainment status of an area under section 107(d) of the CAA does not

have a significant economic impact on a substantial number of small

entities under the Regulatory Flexibility Act. See 46 FR 8709 (January

27, 1981). Because the regulatory impact of reclassification under

section 188(b) of the CAA is no different substantively from that

associated with designations, such actions are also not expected to

have significant impacts on small entities.

EPA wishes to emphasize, however, that the reclassification of the

Phoenix area is only the first step in developing a strategy to bring

ambient concentrations of PM10 in the area to healthful levels. As

with the State's moderate area SIP, which EPA approved on April 10,

1995 (60 FR 18010), development of a control strategy for the State's

serious area SIP will involve an assessment of the economic feasibility

of implementing any particular control measure. If Arizona determines

that a measure cannot be implemented because it is not economically

feasible, the State need only provide EPA with a reasoned justification

for that determination. EPA believes there will be sufficient

opportunity for ADEQ and other State agencies, local planning agencies,

the general public, and the regulated community to assess the economic

impacts of control measure implementation while they develop the

serious area SIP.

B. State Monitoring and Modeling Study

Comment: ADEQ claims that reclassification is not necessary because

the State and local governments have undertaken a study to better

characterize the sources contributing to the nonattainment problem in

the PPA.

[[Page 21375]]

The study will enable the State to define the control measures

necessary to attain and maintain the PM10 NAAQS. As a result the

PPA will be able to demonstrate attainment by implementing reasonably

available control measures (RACM) rather than BACM.

Response: EPA acknowledges the difficulties in assessing the

contributions from various sources to total PM10 concentrations

and fully supports the State's efforts to accurately identify those

sources which have caused the PPA to be in nonattainment of the

standards. Nonetheless, section 188(b)(2) of the CAA does not afford

EPA any discretion in determining whether the area has in fact attained

the PM10 NAAQS by the statutorily mandated attainment date. EPA

regulations generally require three years of ambient monitoring data in

order to assess an area's attainment status. See 40 CFR part 50,

Appendix K. As discussed in section I.D. of this notice, based on air

quality data collected during the years 1992 through 1994, EPA has

determined that the PPA has not attained the PM10 NAAQS.

Moreover, the State recently reported two additional violations of

the PM10 NAAQS at the Chandler monitoring site in 1995. While for

the purposes of this rulemaking EPA is only considering air quality

data from 1992 through 1994, these 1995 violations further support

EPA's determination that PPA has failed to attain the PM10

standard.

C. EPA's Current Review of the PM10 NAAQS

Comment: Reclassification of the PPA is untimely in light of the

pending revision of the PM NAAQS. State and local agencies will have to

spend considerable resources to develop a plan for a standard that may

no longer be in effect.

Response: Section 109(d)(1) of the Clean Air Act requires that

``not later than December 31, 1980, and at five-year intervals

thereafter'' EPA review and revise, if warranted, air quality criteria

and national ambient air quality standards. EPA is currently under

court order to complete its review of the particulate matter NAAQS by

June 28, 1997.

This review may or may not result in a replacement and/or revision

of the PM10 NAAQS. The Agency is currently considering the

addition of a new PM NAAQS that targets fine particulate matter, such

as particles with an aerodynamic diameter less than or equal to a

nominal 2.5 micrometers. However, the Agency is also considering

retaining a PM10 standard. Although the PM NAAQS review process is

incomplete at this time, recent epidemiologic studies show consistent

positive associations of ambient PM exposure with adverse health

effects, including mortality and morbidity. Given the significant

health effects associated with PM, vigorous enforcement of the current

PM10 requirements is critical to ensure protection of the public

health. Until a revision of the NAAQS occurs, the current NAAQS and the

requirements relating to them remain in force. In the event that a new

NAAQS is promulgated, a transition policy that addresses current

requirements and ensures protection of the public health will be

developed.

D. Air Quality Monitoring

Comment: There should be a more detailed review of the

circumstances surrounding the location of the two monitoring sites

which recorded exceedances to insure that the locations are not

anomalies improperly reflecting local conditions. It would not be

appropriate to impose a classification upon the entire region due to

what may be anomalies for just two sites out of nine.

Response: In order to meet Federal monitoring regulations, agencies

which operate air monitoring networks are required to design these

networks in order to meet certain monitoring objectives. These

objectives are to determine: 1) the highest concentrations expected to

occur in the area covered by the network; 2) representative

concentrations in areas of high population density; 3) the impact on

ambient pollution levels of significant sources or source categories;

and 4) general background concentration levels. See 40 CFR part 58,

Appendix D.

Both the South Phoenix and Chandler sites are located in order to

measure PM10 concentrations in areas of high population density.

The Maricopa County Environmental Services Department (MCESD) and ADEQ,

the agencies responsible for operating the pollutant monitoring network

in the PPA, conduct an annual review of the monitoring network as

required by Federal regulations. See 40 CFR part 58.26 and 40 CFR part

58, Appendix F. EPA believes the South Phoenix and Chandler monitoring

stations are correctly sited and meet all applicable Federal

requirements.

Comment: According to section 2.11 of the Quality Assurance

Handbook for Air Pollution Control, PM10 monitors have a precision

error of 10% when addressing the PM10 24 hour NAAQS.

Therefore, two of the recorded violations, with readings below 165

g/m3, could be within the NAAQS when this error variation is

accounted for.

Response: EPA's quality assurance procedures establish minimum

acceptable operating limits for PM10 sampling equipment. The

10% to which the commenter refers is not directly related

to the final PM10 ambient concentration, but rather to the air

flow rate through the PM10 sampler. The ambient concentration is

calculated from the particle mass collected on a filter medium, the

volume of air pulled through the filter, and the amount of time the

sampler is operated. The 10% to which the commenter refers

is the acceptable range of deviation for the air flow rate through the

sampler. Nevertheless, EPA recognizes the validity of the commenter's

concern regarding the 10% threshold. However, this 10%

threshold is not an allowance or a leeway to adjust data, rather it is

a limit which if exceeded alerts the field or laboratory monitoring

personnel to a possible sample validity problem. Readings beyond the

10% threshold can mean heavy filter loading or decreases in the sampler

flow rate. Air flow rates beyond this 10% threshold may necessitate

invalidating all samples collected since the last sampler calibration.

See Quality Assurance Handbook for Air Pollution Control, section

2.11.3.4, Sample Validation and Documentation.

Comment: According to EPA's Exceptional Event Guideline, high winds

are defined as an hourly speed of greater than or equal to 30 mph or

gusts equal to or greater than 40 mph with little or no precipitation.

The western regional climate center in Reno, Nevada reported that

November 20, 1992 was the windiest day of the quarter in the PPA with

wind speeds up to 40 mph and no precipitation. Therefore the exceedance

recorded on that date (156 g/m3) should be classified as an

exceptional event. Furthermore, all of the PM10 NAAQS violations

in the PPA were impacted by short term construction activities. The

Exceptional Event Guideline states that construction and demolition

activities are exceptional events.

Response: EPA has established criteria and procedures to identify

or ``flag'' data which may be affected by ``exceptional events'' in its

``Guideline on the Identification and Use of Air Quality Data Affected

by Exceptional Events,'' July 1986 (Guideline). Under the flagging

system, state and local air pollution control agencies are responsible

for initially identifying and documenting data influenced by

exceptional events. These agencies are expected to develop the

appropriate

[[Page 21376]]

background information necessary to support a decision to flag an

individual piece of data. The agencies must then submit the information

to EPA for concurrence. Flagging a piece of data or data set does not

exclude that data from being used for nonattainment designations or

classifications. The actual exclusion would only be allowed if, as a

result of a public review process, the responsible government agency,

in this case EPA, determines that the data are inappropriate for use in

a specific regulatory activity. Neither the MCESD nor ADEQ requested

that these data be flagged as exceptional events, nor were these data

proposed to be excluded from any specific regulatory action.

Notwithstanding the fact that the State did not initiate the

flagging process, EPA would have evaluated whether the exceedances in

question were affected by exceptional events had the commenter provided

documentation demonstrating that they qualified as such. There are

basically two issues which must be addressed in order to determine

whether an exceedance of the NAAQS was due to an exceptional event.

First, there must be a link between a specific PM10 generating

activity (e.g., forest or structural fire, construction/demolition

activity) and the suspect data. Second, there must be a determination

that the activity is not likely to recur.

Regarding high winds, the commenter only referenced part of the

definition in the Guideline of a high wind event. The definition in

full is ``hourly windspeed of greater than or equal to 30 mph or gusts

equal to or greater than 40 mph, with [little or] no precipitation. The

high wind condition with [little or] no precipitation and dry soil must

be associated with a significant contribution (estimated to be > 85% by

weight) of crustal material on the PM sampling medium.'' The commenter

did not provide any supporting information on the type of particulate

matter which contributed to the PM10 exceedance on November 20,

1992. Furthermore, no information was provided to show that this wind

event was itself exceptional, i.e. that it was not expected to recur.

As to construction activities, the commenter again only sites a

portion of the definition of construction/demolition activities that

would qualify as exceptional events. The Guideline states that

construction/demolition activities that last for only a short period of

time, are within a reasonable distance of the monitoring site and that

are implementing all reasonable control measures may be flagged as

exceptional events. Flagged data should be limited to sites that are

classified as micro- or middle-scale and downwind with respect to the

construction activity. The Chandler monitoring site is classified as a

neighborhood scale site. See 40 CFR part 58, Appendix D for an

explanation of the difference in spatial scales. As with the high wind

claim, the commenter also did not address the likelihood of the

construction activity's recurrence. In the State's approved moderate

area PM10 SIP, construction activities are recognized as

controllable sources of PM10 and are now regulated under Maricopa

County Rule 310.

To summarize, the commenter did not provide any supporting

information or data showing that the high winds or construction

activities did, in fact, have a direct causal link to the PM10

NAAQS exceedances or, if so, the magnitude of the contribution from

these sources. The commenter simply asserted that the high winds and

construction activities occurred. Furthermore, the commenter did not

address the likelihood of the recurrence of these conditions. In fact,

the SIP development process is intended to prevent exceedances from

anthropogenic activities such as construction by providing for planning

by the State and local community to help ensure such activities

adequately mitigate their contribution to PM10 air quality

problems.

Comment: The two locations where violations were recorded are only

two of nine SLAMS sites and data from the seven clean sites should also

be considered in deciding whether the PPA should be reclassified. The

recorded violations are only 14%, 5%, and 4% over the PM10 NAAQS

and these values are not ``seriously'' in excess of the PM10

NAAQS.

Response: Maricopa County's nine station network is only a

representative sample of the PPA's air quality. These nine stations

cover 2,920 square miles. Monitoring is only conducted on a one in

every six day schedule. Therefore, for every one sample taken, there

are five days for which the air quality is unknown. If there were other

sites set up to represent conditions similar to those of the violating

sites, it is possible that more violations would have been recorded.

Pursuant to 40 CFR, part 50, Appendix K, an exceedance is defined

as a value which is measured above the level of the 24 hour standard

after rounding to the nearest 10 g/m3 (i.e. values ending

in 5 or greater are rounded up). Therefore, had the highest recorded

values in the 1992 to 1994 period been 154 g/m3 or less,

the concentrations would not have been considered exceedances of the

NAAQS. However, the PM10 concentrations recorded in the Phoenix

area, 156 g/m3, 158 g/m3, and 171

g/m3, are above that level and are therefore considered

exceedances.

Further, the claim that the exceedances were not ``seriously in

excess'' of the NAAQS is without validity. The PM10 NAAQS are set

at a level required to protect public health. The standards are

designated levels, not ranges, of PM10 above which the air quality

is considered unhealthy. The reclassification of the PPA is based on

the fact that violations of the standards have occurred, and continue

to occur, rather than on the severity of the violations.

E. National PM10 Standard

Comment: EPA should not apply a nationwide PM10 standard to an

arid Southwest region such as the PPA.

Response: Section 109 of the CAA requires EPA to promulgate primary

and secondary NAAQS for certain types of air pollutants. These

standards are based on criteria which reflect current scientific

knowledge of the effect of these pollutants on public health and

welfare.

On July 1, 1987 EPA promulgated the NAAQS for PM10. 52 FR

24663 (July 1, 1987). While the types of sources and the ability to

control them differ from one area of the country to another, the human

health effects of PM10 pollution are the same whether one resides

in New York City or Phoenix. Therefore, in order to protect human

health, the standards must be the same nationwide.

However, unlike the NAAQS, the SIP development process is intended

to address variability in source types. While the CAA does impose

certain minimum control requirements, ultimately it is up to the state

and the affected local communities to choose the particular control

measures that best address their unique air pollution problem. In

developing the control measures, a state may consider the economic and

technological feasibility of implementing a particular control measure.

III. Today's Final Action

EPA is today taking final action to find that the PPA did not

attain the PM10 NAAQS by December 31, 1994, the CAA attainment

date for moderate PM10 nonattainment areas. As a result of this

final finding, the PPA is reclassified by operation of law as a serious

PM10 nonattainment area.

IV. Executive Order (EO) 12866

Under E.O. 12866, 58 FR 51735 (October 4, 1993), EPA is required to

determine whether regulatory actions

[[Page 21377]]

are significant and therefore should be subject to 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 Agency has determined that the finding of failure to attain

finalized today would result in none of the effects identified in

section 3(f). Under section 188(b)(2) of the CAA, findings of failure

to attain and reclassification of nonattainment areas are based upon

air quality considerations and must occur by operation of law in light

of certain air quality conditions. They do not, in-and-of-themselves,

impose any new requirements on any sectors of the economy. In addition,

because the statutory requirements are clearly defined with respect to

the differently classified areas, and because those requirements are

automatically triggered by classifications that, in turn, are triggered

by air quality values, findings of failure to attain and

reclassification cannot be said to impose a materially adverse impact

on State, local, or tribal governments or communities.

V. Regulatory Flexibility

Under the Regulatory Flexibility Act, 5 U.S.C. Sec. 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 Secs. 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.

As discussed in sections II.A. and IV of this notice, findings of

failure to attain and reclassification of nonattainment areas under

section 188(b)(2) of the CAA do not in-and-of-themselves create any new

requirements. Therefore, I certify that today's final action does not

have a significant impact on small entities.

VI. Unfunded Mandates

Under sections 202, 203 and 205 of the Unfunded Mandates Reform Act

of 1995 (Unfunded Mandates Act), signed into law on March 22, 1995, 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 believes, as discussed above, that the finding of failure to

attain and reclassification of the Phoenix Planning Area are factual

determinations based upon air quality considerations and must occur by

operation of law and, hence, do not impose any federal

intergovernmental mandate, as defined in section 101 of the Unfunded

Mandates Act.

List of Subjects in 40 CFR Part 81

Environmental protection, Air pollution control, Intergovernmental

relations, Particulate matter.

Dated: April 29, 1996.

Felicia Marcus,

Regional Administrator.

40 CFR part 81 is amended as follows:

PART 81--[AMENDED]

1. The authority citation for part 81 continues to read as follows:

Authority: 42 U.S.C. 7407, 7501-7515, 7601.

2. Section 81.303 is amended by revising the table for Arizona--PM-

10, to read as follows:

Sec. 81.303 Arizona.

* * * * *

Arizona--PM-10

----------------------------------------------------------------------------------------------------------------

Designation Classification

Designated Area ------------------------------------------------------------------------------

Date Type Date Type

----------------------------------------------------------------------------------------------------------------

Cochise County:

Paul Spur/Douglas planning 11/15/90 Nonattainment............... 11/15/90 Moderate.

area.

Township 23 South, Range

25 East (T23S, R25E):

T23S,R26E

T23S, R27E

T23S, R28E

T24S, R25E

T24S, R26E

T24S, R27E

T24S, R28E

Santa Cruz County:

Nogales planning area........ 11/15/90 Nonattainment............... 11/15/90 Moderate.

The portions of the

following Townships

which are within the

State of Arizona and lie

east of 111 deg.

longitude:

T23S, R13E

T23S, R14E

T24S, R13E

T24S, R14E

Rillito planning area........ 11/15/90 Nonattainment............... 11/15/90 Moderate.

[[Page 21378]]

Townships:

T11S, R9E

T11S, R10E

T11S, R11E

T11S, R12E

T12S, R8E

T12S, R9E

T12S, R10E

T12S, R11E

T12S, R12E

Pima County

Ajo planning area............ 11/15/90 Nonattainment............... 11/15/90 Moderate.

Township T12S, R6W, and

the following sections

of Township T12S, R5W:

a. Sections 6-8

b. Sections 17-20,

and

c. Sections 29-32

Maricopa and Pinal Counties

Phoenix planning area........ 11/15/90 Nonattainment............... 6/10/96 Serious.

The rectangle determined

by, and including--

T6N, R3W

T6N, R7E

T2S, R3W

T2S, R7E

T1N, R8E

Yuma County:

Yuma planning area........... 11/15/90 Nonattainment............... 11/15/90 Moderate.

Townships:

T7S-R21W, R22W;

T8S-R21W, R22W, R23W,

R24W

T9S-R21W, R22W, R23W,

R24W, R25W;

T10S-R21W, R22W,

R23W, R24W, R25W

Pinal and Gila Counties:

Hayden/Miami planning area... 11/15/90 Nonattainment............... 11/15/90 Moderate.

Townships: T4S, R16E T5S,

R16E T6S, R16E plus the

portion of Township T3S,

R16E that does not lie

on the San Carlos Indian

Reservation, and the

rectangle formed by, and

including, Townships

T1N, R13E

T1N, R15E

T6S, R13E

T6S, R15E

Gila County (part):

Payson: T10N, Sections 1-3, 1/20/94 Nonattainment............... 1/20/94 Moderate.

10-15, 22-27, and 34-36 of

R9E; T11N, Sections 1-3, 10-

15, 22- 27, and 34-36 of

R9E; T10-11N, R10E; T10N,

Sections 4-9, 16-21, and 28-

33 of R11E; T11N, Sections 4-

9, 16-21, and 28-33 of R11E..

Mohave County (part):

Bullhead City: T21N, R20-21W, 1/20/94 Nonattainment............... 1/20/90 Moderate.

excluding Lake Mead National

Recreation Area; T20N, R20-

22W; T19N, R21-22W excluding

Fort Mohave Indian

Reservation..

Rest of State................ 11/15/90 Unclassifiable..............

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[FR Doc. 96-11736 Filed 5-9-96; 8:45 am]

BILLING CODE 6560-50-P