Federal Register / Vol. 58, No. 5 / Friday, January 8, 1993 / Rules and Regulations

ENVIRONMENTAL PROTECTION

AGENCY

40 CFR Part 81

(AD-FRL-4158-4)

RIN NO. 2060-AC56

Reclassification of Moderate PM-10

Nonattainment Areas to Serious Areas

AGENCY: Environmental Protection

Agency (EPA).

AClION: Final rule.

SUMMARY: Under section 188(b)(1) of the

Clean Air Act, EPA is reclassifying as

serious four areas in California and one

area in Nevada which were initially

classified as moderate nonattainment

areas for PM-10 (particles with an

aerodynamic diameter less than or equal

to a nominal 10 micrometers).

EFFECTIVE DATE: This action will become

effective on February 8, 1993.

ADO ESSES: The technical reports

referenced in today's document can be

found in Public Docket No. A-91-53.

The docket is located at the U.S. EPA

Air Docket, Rm. M-1500, Waterside

Mall.LE-131, 401 M St., SW.,

Washington, DC 20460. The docket may

be inspected from 8:30 a.m. to 12 noon

and from 1:30 p.m. to 3:30 p.m. on

weekdays except for legal holidays, and

a reasonable fee may be charged for

copying.

FOR FURTHER INFORMATION CONTACT: Eric

Ginsburg, Air Quality Management

Division, Mail Drop 15, Office of Air

Quality Planning and Standards, U.S.

Environmental Protection Agency,

Research Triangle Park, NC 27711, (919)

541-0877.

SUPPLEMENTARY INFORMATION:

ELECTRONIC AVAILABILITY: This document

is available as an electronic file on The

Federal Bulletin Board at 9 a.m. the day

of publication in the Federal Register.

By modem dial 202-512-1387 or call

202-512-1530 for disks or paper copies.

This file is available in Postscript,

Wordperfect 5.1, and ASCII.

I, Background

On the date of enactment of the 1990

Clean Air Act Amendments, PM-10

areas meeting the qualifications of

section 107(d)(4)(B) of the Act were

designated nonattainment by operation

of law [see generally, 42 U.S.C.

7407(d)(4)(B) of the Act; references in

this notice to "the Act" or "the Clean

Air Act" are to the Clean Air Act, as

amended, 42 U.S.C. 7401 et seq.). These

areas included all former ;rcnup I areas

identified in 52 FR 29383 (August 7,

1987) and clarified In 55 FR 45799

(October 31, 1990), and any other areas

violating the PM-10 standards prior to

January 1. 1989 (many of these areas

were Identified by footnote 4 in the

October 31, 1990 Federal Register

document). A Federal Register

document announcing all of the areas

designated nonattainment for PM-10 at

enactment and classified as moderate

was published in 56 FR 11101 (March

15, 1991). A followup notice correcting

some of these areas was published

August 8, 1991 (56 FR 37654). These

nonattainment designations and

moderate area classifications were

codified in 40 CFR part 81 in a Federal

Register document published on

November 6, 1991 (56 FR 56694). All of

the areas in the Nation not designated

nonattainment at enactment were

designated unclassifiable [see section

107(d)(4)(B)(iii) of the Act].

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. In accordance with

section 188(a) of the Act, at the time of

designation, all PM-10 nonattainment

areas are initially classified as moderate

by operation of law.

A moderate area can subsequently be

reclassified as serious either before the

applicable moderate area attainment

date if EPA determines the area cannot

"practicably" attain the PM-10 NAAQS

by this attainment date, or following the

passage of the applicable moderate area

attainment date if EPA determines the

area has failed to attain the standard.

Under the plain meaning of the terms

of section 188(b)(1) of the Act, EPA has

general authority to reclassify at any

time before the applicable attainment

date any area EPA determines cannot

practicably attain the standard by such

date, Accordingly, section 188(b)(1) of

the Act is a general expression of

delegated rulemaking authority.In

addition, subparagraphs (A) and (B) of

section 188(b)(1) of the Act mandate

that EPA reclassify "appropriate" PM-10

nonattainment areas at specified time

frames (i.e., by December 31, 1991 for

the initial PM-10 nonattainment areas,

and within 18 months after the SIP

submittal due date for subsequent

nonattainment areas). These

subparagraphs do'not restrict EPA's

general authority but simply specify

that, at a minimum, it must be exercised

at certain times.' Any decision by EPA

to reclassify an area as serious before the

applicable attainment date will be based

(The EPA!s interpretation of the relasalflcation

provisions in section Tas(bX1) of the Act ws * discussed in the proposal for today's final rule and

in the "General Preamble to Title lof the Cle Alt

Act Amendments of 1990," 57 FR 13537-13538

(April 16, 1992).

on facts specific to the nonattainment

area at issue, and will only be made

after providing notice in the Federal

Register and an opportunity for public

comment on the basis for EPA's

proposed decision.

In those cases where EPA determines

that an area has failed to attain the

NAAQS by the applicable attainment

date, the area is reclassified as serious

by operation of law [see section

188(b)(2) of the Act]. The EPA must

publish a notice in the Federal Register

of such determinations and consequent

reclassifications within 6 months

following the applicable attainment

date.

In accordance with section

188(b)(1)(A) of the Act, EPA is

announcing the reclassification of those

initial moderate nonattainment areas

which EPA has determined at this time

cannot "practicably" attain the PM-10

NAAQS by December 31, 1994, the

applicable attainment date [see section

188(c)(1) of the Act). As explained

further below, today's action discharges

EPA's statutory obligation under section

188(b)(1)(A) of the Act which required

EPA to reclassify appropriate initial

moderate PM-10 nonattainment areas as

serious by December 31, 1991.

11. Determining That an Area Cannot

Practicably Attain

Generally, EPA will rely on

information in the State's SIP submittal.

suchas the control strategy, attainment

demonstration, and compliance

schedule to determine whether it is

practicable to attain the NAAQS in that

area by the applicable attainment date.

The SIP's which were due on November

15, 1991 for the initial PM-10 moderate

nonattainment areas were required to

contain, among other requirements, a

control strategy based upon the use of

reasonably available control measures

(RACM) which includes reasonably

available control technology (RACT)

[see sections 172(c)(1) and 189(a)(1)(C)

of the Act]. 2 The States were also

required to demonstrate that the SIP's

provide for timely implementation of

RACM and attainment of the NAAQS.

The RACM must be implemented in the

initial PM-10 nonattainment areas by

December 10, 1993. and th, rvreas must

attain the standard as expeditiously as

practicable, but no later than December

31, 1994, unless an area can

demonstrate that attainment by that date

2The RACr is a subset of the overarching RACM

requirement Iso[ section 172(c(1) of the Act). The

RACT nerally refers to only the technological

Scontrol measures which apply to large stationary sources. Any reference toRACM herein implicitly

includes RACT.

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Federal Register / Vol. 58, No. 5 / Friday, January 8, 1993 / Rules and Regulations

is impracticable [see sections 188(c)(1)

and 189(a)(1)(C) of the Act].

There are at least three reasons why

an area may not practicably attain the

standards by the applicable attainment

date. First, implementation of the SIP

control strategy, including RACM, may

not create sufficient emissions

reductions to bring the area into

attainment. The State will have

demonstrated that an initial PM-10

nonattainment area cannot practicably

attain the NAAQS by the applicable

attainment date if the implementation of

RACM by December 10, 1993 will not

achieve sufficient emissions reductions

to attain the standards by December 31,

1994. The EPA has interpreted RACM,

including RACT, to be those emissionreduction measures which EPA believes

are generally reasonable considering

technological feasibility and costs of

control. The State should prepare a

reasoned justification to show that a

particular control measure for an

existing source is infeasible or otherwise

unreasonable and, therefore, would not

constitute RACM. 3 Otherwise, the SIP

should include implementation of all

available emission reduction measures

that have not been demonstrated to be

unreasonable.

Second, nonanthropogenic sources

which cannot reasonably be controlled

may contribute significantly to the

violation of the PM-10 NAAQS in the

area. Moreover, section 188(0 of the Act

authorizes the Administrator to waive a

specific attainment date for an area

where the Administrator determines

that nonanthropogenic sources

contribute significantly to the violation

of the PM-10 standard in the area.

Section 188(0 of the Act also provides

that the Administrator may, on a caseby-case basis, waive certain

requirements applicable to serious areas

where the Administrator determines

that anthropogenic sources of PM-10 do

not contribute significantly to violation

of the PM-10 standard in the area. 4 Note

that an area is reclassified if EPA

determines that it cannot practicably

meet the applicable attainment date or

that it has failed to meet such date.

Thus, reclassification is keyed to a

specific date. If that date is waived, the

area would not be subject to

reclassification because there simply

would be no date that the area cannot

practicably meet or that the area fails to

I See the "General Preamble to Title I of the Clean

Air Act Amendments of 1990," 57 FR 13540-13544

and 13560-13561 (April 16. 1992). 4 The EPA has made available to the public draft

guidance on the application of the waiver

provisions under section 188(f) of the Act [see 57

FR 31477 (July 16. 1992)1 and will finalize that

guidance at a later date.

meet. Thus, while nonanthropogenic

sources which cannot be reasonably

controlled may be a reason an area

cannot practicably attain, if such area

qualifies for a waiver of the attainment

date under section 188(f) of the Act, it

may also be a basis for not reclassifying

the area. Note that in today's action, in

order not to undermine the waiver

provision, EPA has given some

consideration to Spokane's potential

exclusion from reclassification under

section 188(f) of the Act in determining

whether it is "appropriate" to reclassify

that area at this time,

Third, the area may be significantly

impacted by PM-10 emissions

emanating from outside the United

States. In the latter case, the State may

demonstrate that the area qualifies for

treatment under section 179B(d) of the

Act, which provides that areas which

would have attained the NAAQS by the

applicable attainment date but for

emissions emanating from outside the

United States shall not be subject to

reclassification requirements under

section 188(b)(2) of the Act (see 56 FR

58662). In such cases of international

transport, the State will be expected to

demonstrate and quantify the

international contribution of PM-1 in

the affected area. Any State containing

an area which may qualify for treatment

under this provision still must timely

submit a moderate area SIP for such

area. In order to have its moderate PM10 SIP approved under section 179B(a)

of the Act in addition to demonstrating

that it would have timely attained the

PM-10 NAAQS but for international

emissions, the State must submit a

moderate SIP meeting all requirements

applicable to moderate PM-10

nonattainment areas other than the

requirement that it demonstrate timely

attainment.

The EPA may also consider

reclassifying moderate areas for which a

SIP has not been submitted whenever it

becomes apparent, e.g., because of an

extensive delay in submitting the SIP,

that the area cannot practicably attain

the standards by the end of 1994. The

EPA also may determine that an area

cannot practicably attain the PM-10

NAAQS by the applicable date when the

State submits an incomplete or

otherwise inadequate SIP for the area,

which would not assure timely

attainment and the State does not act

expeditiously to correct such

deficiencies. The EPA has notified

certain States of their failure to submit

PM-10 SIP revisions for the initial areas

by the November 15, 1991 deadline and

has notified some States that their SIP's

are incomplete [see, e.g., 57 FR 19906

(May 8, 1992)]. These actions

constituted determinations under

section 179(a)(1) of the Act and were

communicated in letters to affected

State Governors. As provided under

section 179(a) of the act, States

containing areas for which EPA has

made such determinations have up to 18

months from EPA's determination to

submit the plan or plan revision before

EPA is required to impose either the

highway funding sanction or the

requirement to provide two-to-one new

source offsets described in section

179(b) of the Act. The EPA's

determination also triggered the

requirement for EPA to impose a

Federal implementation 'plan as

provided under section 110(c)(1) of the

Act. In conjunction with the possible

imposition of sanctions, EPA may

propose or issue a final determination to

reclassify the area as serious.

Reclassification of an area as serious

does not obviate the legal requirement

to implement a moderate area SIP. 5

III. Determination for Reclassification

As noted, the PM-10 reclassification

provisions contain a general delegation

of authority to the Administrator

indicating that he "may" reclassify as

serious "any" moderate nonattainment

area that he determines "cannot

practicably attain" the PM-10 NAAQS

by the applicable statutory deadline [see

section 188(b)(1) of the Act]. By its plain

terms, this provision confers broad

discretionary authority on the

Administrator (hereafter referred to as

the "discretionary" reclassification

authority). As a subset of that broad

authority, section 188(b)(1)(A) of the Act

mandates that the Administrator

propose to reclassify "appropriate"

initial moderate nonattainment areas as

serious by June 30, 1991 and take final

action by December 31, 1991.6

As described above, initial moderate

area SIP's were due November 15, 1991.

Thus, EPA did not have the benefit of

these required SIP submittals before

developing and issuing the

reclassification proposal required under

section 188(b)(1)(A) of the Act. In the

absence of better information, EPA used

surrogate criteria as evidence of an

area's ability to timely attain and

proposed to reclassify 14 areas relying

on that criteria. However, in its

proposal, EPA also contemplated that it

may get better information about an

area's ability to attain in, for example,

5 See 56 FR 58658 (November 21. 1991), note 3. 6

This directive does not restrict EPA's general

authority, but simply specifies that it must be

exercised, at a minimum, in accordance with

certain dates for areas designated nonattainment

under section 107(d)(4)(b) of the Act.

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3336

the form of the required SIP submittals.7

Thus, EPA entertained the possibility of

receiving information which rebutted

the indicators (56 FR 58658; Nov. 21,

1991): Thus, while EPA believes the

indicators for assessing an area's ability,

or inability, to attain area reasonable.

they are rebuttable on a case-by-case

basis.

Since this proposal, EPA has received

SIP's for some of the 14 areas identified

and has received other information

bearing on the determination of whether

it is appropriate to reclassify such areas

at this time. For example, EPA has

received SIP submittals and detailed SIP

work plans for some of the areas

identified in EPA's proposal which

purport to provide for timely

attainment. As noted, EPA is directed by

the statute to make a final decision to

reclassify appropriate areas by a date

certain and that date has already passed.

Due to these time constraints, EPA

cannot fully review the SIP's or wait for

SIP's which have not yet been

submitted. On the other hand, EPA

believes this information is relevant and

should be given at least some

consideration. The EPA has reconciled

this dilemma by preliminarily reviewing

the SIP submittals and other relevant

information (including the public

comments submitted in response to

EPA's proposal). To the extent such

information indicates, contrary to the

criteria identified in EPA's proposal,

that the area may be able to practicably

attain by the end of 1994, EPA is

determining that it is not appropriate to

reclassify the area at this time and,

hence, has declined to take final action

on such area in today's rulemaking. Nevertheless, EPA may conclude at a

later date that one of these areas cannot

practicably attain. For example, a full

review of the required SIP submittal

may reveal that the area cannot

practicably attain. In addition, the

delays in developing and submitting the

required November 15, 1991 SIP

submittal may become so prolonged that

the area cannot practicably attain. In

such instances, EPA would exercise its

discretionary authority under section

188(b)(1) of the Act to reclassify the

area.

Note that EPA's decision not to

reclassify these areas at this time does

not mean that any SIP relied on in

I The statute dos ree specify what information

EPA must consider in exercising the authority

delegated to it by section 168(b)(1) of the AcL Since

the statute does not address this precise question. EPA may base a decision that an ara cannot

practicably attain by the applicable date on any relevant Iaformatioa, which may inlcude SIP

submittals. modeling demonstrations, or other

roasonable information (Chevron U.S.A. Inc. v. NPDt. 467 U.S. 837. 842-845 (1984)1.

making such determination will be

approved. If a SIP purports to

demonstrate attainment, that is simply

strong evidence contradicting EPA's

criteria and militating against

reclassifying the area at that time. The

EPA may conclude after a full review of

the SIP that it has deficiencies that

warrant less than full approval, Further,

if such deficiency would preclude an

area from timely attaining, then EPA

may exercise its discretionary authority

to reclassify the area. In any case, no

binding EPA decision about the

approvability of any such SIP will be

made until the public has had an

opportunity to comment on such

decision.

In some instances, EPA's preliminary

review of the SIP for an area revealed

that the area could not practicably attain

by the required date and should be

reclassified. These are the areas

reclassified in today's action.

Specifically, in today's action, EPA is

reclassifying five areas (listed in Table

1 and discussed below) which EPA has

determined, at this time, cannot

practicably attain by December 31, 1994.

The EPA has not received public

comments or other information during

the public comment period in

opposition to EPA's decision to

reclassify these areas.

Note that, as indicated in EPA's

proposal, reclassification of an area in

no manner obviates the obligation to

submit a moderate area SIP (56 FR

58658; Nov. 21, 1991). Thus, those areas

reclassified in today's action must,

among other things, submit provisions

to assure that reasonably available

control measures (including reasonably

available control technology) are

implemented no later than December

10. 1993 and submit a demonstration

that attainment by December 31, 1994 is

impracticable.

Two areas identified in EPA's

proposal have requested treatment

under the International Border

provision (see section 179B of the Act).

While EPA has not yet received a PM10 SIP for either of these meas, EPA has

significant information suggesting that

the areas may qualify for treatment

under section 179B of the Act. including

an exclusion from reclassification under

section 179B(d) of the Act8. Because

ISection 179B(d) of the Act states that areas

demonstrating attainment of the NAAQS but for

emissions emanating from outside the United States

shall not b vublect to section 18o(bX2) of the Act

(reclassifiction for failure to attain). By amalogy to

this provison md applying rules of statutory

construction, ,PA will not reclassify before the

applicable attainment date areas which can demonstrate attainment of the NAAQS but for

emissions emanating from outside the United States

[see section i8es(b(1) of the Act). First. section 179B

EPA has information indicating that

these areas are significantly impacted by

emissions emanating from Mexico, but

insufficient information to determine

whether they would qualify for

treatment under section 179B of the Act,

EPA is declining to reclassify these

areas at this time. This represents, in

some fashion, a change in position from

EPA's proposal in that EPA believes the

information currently available to EPA,

standing alone, is a sufficient basis upon

which to conclude that these areas

should not be reclassified at this time.

So as not to undermine section 179B of

the Act, EPA believes it is reasonable to

conclude that it is not "appropriate" to

reclassify these areas at this time where

there is some significant evidence

suggesting that these areas may qualify

for an exclusion from reclassification

under that provision.

However, EPA may reclassify these

areas using its discretionary

reclassification authority should EPA at

some time in the future determine, for

example, that the areas cannot

practicably attain and do not qualify for

exclusion from reclassification under

section 1798(d) of the Act. For example,

prolonged delays in submitting the

required SIP for these areas may lead

EPA to conclude at some future time

that these areas cannot practicably

attain by the end of 1994.

In sum, in today's final rulemaking.

EPA is reclassifying those areas which

EPA has determined at this time cannot

practicably attain the PM-10 NAAQS by

the applicable statutory attainment date.

Today's action wholly discharges EPA's

statutory duty to reclassify "appropriate" moderate areas as serious

by December 31, 199 Isee section

188(b)(1)(A) of the Act]. However, EPA

also reserves the right to use its broad

discretionary authority under section

188(b)(1) of the Act to reclassify at a

later date the nine areas EPA declined

to reclassify in today's action. If, at

times in the future before the applicable

attainment date, EPA determines that

such areas cannot practicably attain the

PM-10 NAAQS, EPA will take final

of the Act evinces a general congressional intent not

to penalize areas where emissions emanating from

outside the country are the but4or case of the PM10 attainment problems. Further, If EPA were to

reclassify such areas before te applicable

attaiment date, EPA. in effect, would be reading

section 179(d) of the Act out of ts statute.

Specifically. if EPA proceeded to reclassify before

the applicable attainment date thobe areas qMaKly o Ie t udMer stMio t70 of Ow

Act, an area would never be subject to the provision

in section 179B(d) of the Act which prohibits EPA

from reclassifying such areas afer the applicable

attainment date. Canoso of statuo construction

counsel against Interpretiag the law such that

language is randered mere auplusage (se SS F at

58662; Nov. 21, 1991. note 12).

Federal Register / Vol. 58, No. 5 / Friday, Jawaary 8, 1993 / Rules and Regulations

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Federal Register / Vol. 58, No. 5 / Friday, January 8, 1993 / Rules and Regulations

action to reclassify these areas. Note that areas not reclassified today will remain rulemaking record for any future

the materials in the rulemaking docket in force as part of the ongoing decision to reclassify these areas

for today's action pertaining to the nine utilizing EPA's discretionary authority.

TABLE 1.-AREAS WHCH EPA IS RECLASSIFYING AT THIS TIME'

EPA region Area of concern Sources

IX San Joaquin Valley. CA FDO, secondary PK PB"

IX Owens Valley, CA FD IX South Coast Air Basin. CA Secondary PMK FD

IX Coect&*e Valley. CA FD

IX Las Vegas, NV FD

5PB ull d c oe for go" areas elasafied In toa'* document are Scated In a* evislons to 40 CFA peat 81 alM end of tis document 3 FD.FuglNO dust. PS - Prascrtbed bumft.

IV. Areas Which EPA is Reclassifying at

This Time

Coachella Valley, California. The EPA

is reclassifying the Coachella Valley

nonattanment area at this time because

the SIP for the area submitted to EPA by

the State of California on November 15,

1991 suggests that it is not practicable

to provide for attainment of the annual

and 24-hour PM-10 NAAQS until

December 31, 1995, 1 year after the

moderate area attainment date. The PM10 SIP for the Coachella Valley indicates

that 97 percent of the PM-10 emissions

are due to fugitive dust sources. The

most significant of these sources are

construction activities, reentrained dust

from paved roads, and windblown dust

from agricultural and disturbed lands.

Las Vegas, Nevada. The EPA is

reclassifying the Las Vegas nonattainment area due to the fact that

the PM-10 SIP submitted to EPA by the

State of Nevada on December 6, 1991

suggests that implementation of the

control measures contained in the SIP

will result in sufficient emissions

reductions to attain the annual PM-10

NAAQS by December 31, 1994, but that

it will not be practicable to timely attain

the 24-hour PM-10 NAAQS. A 1989

valley-wide emissions inventory

suggests that a substantial amount of

PM-10 emissions are due to fugitive

dust sources. Microinventories indicate

that significant sources of fugitive dust

include construction activities, paved

and unpaved roads, and windblown

dust from disturbed vacant land

including disturbed desert.9

9The EPA used the occasion of the publication of the PM-iO reclesslificatm proposal to request

public input on issues related to Its preliminary

efforts to develop a nonbinding policy addressing

the section 388(f) of the Act PM-1O waiver

provisions 156 FR 5861-58662; Nov. 21, 1991). The

Clark County Health Disbdct submitted comments

setting out some of Its suggestions regarding the

Implementation of 188() of the Act. Clark County's

comments address EPA's Interpretation of

anthropoenlic and nonanthxopogenlc under section

188110 of the Act and do not request that EPA alter

Its proposed decision to reclassify this area. Moreover. Clark County does substantiate to what

Owens Valley, California. The EPA is

reclassifying the Owens Valley

nonattainment area at this time based

upon the fact that the PM-10 SIP

submitted to EPA by the State of

California on January 9, 1992 suggests

that the area cannot practicably attain

the PM-lO standards by December 31,

1994. Ambient PM-10 levels in Owens

Valley are among the highest in the

country. In 1989, for instance, the

highest 24-hour PM-10 concentration

observed in the area was 1861

micrograms per cubic meter (ug/m3), in

contrast to the NAAQS of 150 ug/m 3. The PM-10 SIP for Owens Valley

includes an analysis of wind direction

and wind speed on days when PM-10

levels are high, which indicates that the

major source causing violations of the

PM-10 NAAQS in this area is Owens

Dry Lake. Owens Dry Lake covers

approximately 110 square miles near the

south end of the planning area.

Approximately 60 square miles of the

lake is dry. The Great Basin Unified Air

Pollution Control District is currently

developing and evaluating a variety of

mitigation measures. The final

mitigation program is scheduled for

implementation in 1995. The Great

Basin Unified Pollution Control District

submitted comments to EPA supporting

the reclassification of this area.

San Joaquin Valley. California. The

EPA is reclassifying the San Joaquin

nonattainment area due to the fact that

the PM-10 SIP for San Joaquin Valley

extent the October 25. 199 exceedance example was in fact attributable to nonanthropogenic sources. In any evant, the county's comments have no bearing on today's action which. as indicated.

ultimately was based on the SIP developed for that area. Finally, EPA recently made a draft of its

section 188(f) of the Act policy available to the

public and held a public meeting to provide the

public with additional opportunity to comment on its contents 157 FlR 31477; July 16, 1992). That draft

Indicates that a decision to reclassify an area as serious will not affect an am's eligibility for a waiver. The EPA will consider the Clark County comments addressing mction ( of the Act

issues as It reises its draft section 168(f) of the Act

policy in light of the various comments received.

submitted to EPA by the State of

California on December 24,1991

suggests that the area cannot practicably

attain the PM-10 NAAQS by December

31, 1994. Moreover, the area has not

projected attainment before the

December 31. 2001 serious area

attainment date. Violations of the PM-10

NAAQS in the San Joaquin Valley are

dominated by two source cateories: (1)

primary PM-l0 sources, including

reentrained road dust, construction

activities, and farming operations, and

(2) secondarily-formed PM-10,

including ammonium nitrate and

ammonium sulfate. On days when

primary PM-10 emissions dominate,

fugitive dust emissions account for

nearly 80 percent of the PM-10 mass. On

days when secondary PM-10 dominates,

nitrates and sulfates account for 63

percent of the PM-la mass. The

attainment strategy for the San Joaquin

Valley will rely heavily on the control

of widespread fugitive dust sources and

the control of precursors of PM-lO.

including nitrogen dioxide, sulfur

dioxide, and volatile organic

compounds.

South Coast Air Basin, California. The

EPA is reclassifying the South Coast Air

Basin at this time because the SIP for

the South Coast Air Basin projects that

it is not practicable to attain the 24-hour

PM-10 NAAQS until the year 2000 and

attainment of the annual PM-10 NAAQS

by the year 2006. These dates are well

beyond the December 31, 1994 mderate

area attainment date. The basin-wide

emissions inventory for the area covers

approximately 6600 square miles and

indicates that 91 percent of primary PM10 emissions are due to area sources,

primarily reentrained road dust. With

projected increases in population (31

percent) and increases in vehicle miles

travelled (62 percent), PM-10 emissions

associated with reentrained road dust

are expected to increase from 663 tons/

day In 1987 to 1025 tons/day in 2010.

In addition to the widespread sources of

primary PM-10 emissions, source

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contribution estimates indicate that

secondarily-formed particles (nitrates

and sulfates) can contribute as much as

52 percent of the 24-hour PM-10 mass

and as much as 37 percent of the annual

PM-10 mass. Therefore, the attainment

strategy for the South Coast Air Basin

will also rely heavily on the control of

important precursors to PM-10

including nitrogen dioxide, sulfur

dioxide, and volatile organic

hydrocarbons.

V. Areas Which EPA is not

Reclassifying at This Time

While EPA is taking final action to

reclassify the five areas described above,

EPA is not reclassifying the nine areas

listed in Table 2 at this time, including

those areas which EPA has determined,

in its preliminary assessment, to be

affected by international transport.

Generally, EPA has information for

these areas indicating that they may

practicably be able to attain the PM-10

NAAQS or may be excluded from

reclassification due to international

transport [see section 179B(d) of the

Act). Thus, EPA believes it is premature

to reclassify these areas at this time.

However, as noted, EPA holds open the

possibility of reclassifying these areas

using its discretionary authority under

section 188(b)(1) of the Act. This will

permit EPA to undertake a

comprehensive review of each area's

control strategy. The EPA anticipates

that it will take final action on its

proposal to reclassify these areas

because they cannot practicably attain at

the time it takes rulemaking action on

each area's SIP. Note also that if a PM10 SIP control strategy and

demonstration have not yet been

submitted for an area, EPA may

conclude at some future date that the

area cannot practicably attain due to

protracted delays in making such

submittal. A more specific discussion

follows below for each of these nine

areas, including the significant public

comments which EPA has received.

TABLE 2.-AREAS WHICH EPA Is NOT RECLASSIFYING AT THIS TIME'

EPA region Area of concern Sources

III Liberty, Lincoln, Port Vue, and Glassport Boroughs and the City of Clairton, PA Point

V Oglesby, IL Point

ViII Ubby, MT FD2, RWC 4

. PB

VIII Utah Co., UT Points

IX Paul Spur, AZ Point, FD

IX Nogales, AZ International , FD

IX Imperial Valley, CA FD, International PB

X Kiamath Falls, OR FD, RWC, PB

X Spokane, WA FD, PB, RWC

'The ful legal deecrtptions for those areas which EPA is not reclasstytig at this time can be bund at 56 FR 5684 (Nov. 6, 1991). FD - Fugitive dust. 3P1 3 Preecrbed buming. 4RWC - Resldential wood combustion. In rrational - Intemabornsl tansport of PM-tO. sPoint - Dominam point source impact.

Liberty Borough, Pennsylvania. The

EPA has determined that, at this time,

it is not appropriate to reclassify the

Liberty Borough nonattainment area to

serious. This decision is based on

comments and information received

during the public comment period

regarding the ability of Allegheny

County to attain and maintain the PM10 standard by December 31, 1994. The

decision is also based on the

commitment by the Allegheny County

Bureau of Air Pollution Control to

submit an applicable implementation

plan which demonstrates the attainment

of the PM-10 NAAQS by the moderate

area attfinment date (i.e., December 31,

1994).

The Liberty Borough nonattainment

area is comprised of Liberty, Lincoln,

Port Vue, Glassport Boroughs, and the

City of Clairton in Allegheny County,

Pennsylvania (56 FR 56823; Nov. 6,

1991). The area is heavily industrialized

with a diverse mix of sources including

steel manufacturing, utilities, and

industrial boilers. These sources

generate both point source PM-10

emissions and fugitive dust. In 1989 and

1990, emissions control measures were

implemented in the nonattainment area

in addition to those measures which

had been installed previously.

However, EPA has not received a PM10 SIP for the Liberty Borough

nonattainment area. On December 16,

1991, the EPA Regional Administrator

sent a-letter notifying the Governor of

Pennsylvania of EPA's determination

that the State had failed to submit the

PM-10 SIP for Allegheny County by the

statutory submittal date of November

15, 1991 (see, e.g., 57 FR 19906, May 8,

1992). This determination started the

18-month timeclock for the imposition

of sanctions and the 2-year timeclock for

promulgation of a Federal

implementation plan.

The EPA did receive a "PM-10 work

plan" from the Allegheny County

Health Department on March 26, 1992.

The work plan commits to.attainment of

the PM-10 NAAQS by the statutory

attainment date of December 31, 1994.

It summarizes the procedures to be

followed for the development of the SIP

submittal, including modeling and

monitoring air quality in the area,

conducting an emissions inventory, and

producing a control strategy. The work

plan also establishes a schedule for SIP

submittal, indicating that the schedule

will be met through a cooperative effort

with EPA. The schedule projects that

the SIP will be submitted to EPA by

June 15, 1993.

The EPA received more detailed

comments on its proposal to reclassify

the Liberty Borough nonattainment area

than on its proposed action on other

areas. Rather than discuss those

comments and EPA's responses in detail

here, EPA has placed a document in the

docket accompanying this notice which

describes those comments and explains

further the rationale for EPA's decision

not to reclassify the Liberty Borough

nonattainment area as serious at this

time.

Comments were received from the

local air pollution control agency, the

Commonwealth of Pennsylvania,

affected industries, local citizens, and

public interest groups. Those

commenters opposing reclassification

based their views on assertions that

recent improvements in air quality are

the result of locally-instituted controls,

that EPA did not adequately consider

the air quality impact of those controls

in its decision to propose

reclassification of this area, and that the

PM-10 work plan provides evidence of

the State's commitment to, and the

practicability of, attaining the PM-10

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NAAQS by December 31, 1994. For

these reasons, some of the commenters

indicated that it would be premature for

EPA to reclassify this area. Comments.

favoring reclassification were based

primarily on concerns about poor air

quality in the area, on disagreement as

to the-cause of recently-observed

improvements in air quality, on

assertions that the State's failure to

submit a SIP by the November 15, 1991

due date precludes the area's ability to

timely attain the NAAQS, and on the

belief that reclassification would best

advance the goal of expeditious

attainment of the NAAQS.

Briefly, EPA has based its decision on

the evidence provided in the Allegheny

County Health Department's work plan

in support of that area's commitment:to

attain the NAAQS by December 31,

1994. The EPA has further based its

decision on the fact that commenters

favoring reclassification have not

provided any evidence which rebuts the

State's and county's assertions that

attainment by December 31, 1994 is

practicable. The EPA notes in response

to those favoring reclassification that

reclassifying the area at this time would

result in the requirement that the area

implement additional control measures,

but would also permit the State to

postpone attainment potentially up to

the statutory serious area attainment

date of December 31, 2001.10 By not

reclassifying the area as serious, EPA

intends to enforce the statutory

moderate area requirement for the State

to adopt a plan which provides for

attainment of the NAAQS as

expeditiously as practicable, but not

later than December 31, 1994. The EPA

believes that the principal concerns

expressed by the commenters favoring

reclassification-the need to promote

near-term improvements in air qualityare better served by not taking final

action to reclassify an area at this time

where there is some reasonable

evidence that the area may practicably

attain by December 31, 1994.

Spokane, Washington. The EPA is not

taking final action to reclassify the

Spokane nonattainment area at this

time, but will make a final decision at

the time the Agency takes rulemaking

action on the SIP. This will permit EPA

the opportunity to comprehensively

review the SIP and to assess the claims

that nonattainment in the area is

attributable, at least in part, to

nonanthropogenic dust storms, and that

the area is potentially eligible for a

18 Section 188(b)(2) of the Act requires that such

serious nonattainment areas attain the NAAQS as expeditiously as practicable, but not later than

December 31. 2001.

waiver of-the December 31, 1994

attainment date under section 188(f) of

the Act, The EPA cannot reject or accept

these claims at the present time, The

Agency is currently reviewing the SIP

for Spokane, giving particular

consideration to any anthropogenic

contributions to emissions that may be

reentrained during the area's dust

storms. The EPA will determine

Spokane's eligibility for a waiver of the

moderate area attainment date under

section 188(f) of the Act and will make

a final decision on reclassification when

the Agency has completed its review of

the area's SIP.

Comments received from 14 private

citizens and government, industry, and

environmental groups attribute

Spokane's nonattainment status to

nonanthropogenic dust storms. One

commenter asserted that these dust

storms emanate from the approximately

100,000 acres of undeveloped, untilled

land southwest of Spokane, and to

approximately 500,000 acres of

farmland vulnerable to soil erosion due

to high winds. According to the

Spokane County Conservation District,

such soil erosion is especially prevalent

after harvest and prior to the emergence

of the new crop, stating that it is not

possible to prevent windblown dust

during this vulnerable period. They add

that, when compounded by high winds,

preventing this windblown dust is

"beyond the realm of legislation or

regulation."' One conservation farmer

indicated, however, that farmers have

been working closely with the Soil

Conservation Service to mitigate the

erosion to their cropland.

In addition to comments regarding

nonanthropogenic sources of PM-10 in

Spokane County, 3 elected officials in

Washington State, the Intermountain

Grass Growers Association, 3 Spokane

County public agencies, and I private

corporation contended that the severe

duststorms in the Spokane

nonattainment area should be treated as "exceptional events," as discussed in 40

CFR part 50, Appendix K. section 2.4.

As such, the commenters believe that

contributions from these dust storms

should be discounted when measuring

exceedances of the PM-10 NAAQS.

Because the State has measured 7 such

occurrences during the 3-year reporting

period, there is reason to believe that

these events happen with a regularity

which would disqualify them from

treatment as exceptional events. Again,

EPA will make a final determination

regarding this claim following a

comprehensive review of the SIP

' Letter from Spokane County Conservation

District to Ken Woodard. December 17. 1991.

submittal. One commenter urged EPA to

classify this area as serious, but did not

substantively address whether the area

cannot practicably attain by the

applicable attainment date or the

likelihood of the area qualifying for a

waiver of its moderate area attainment

date under section 188(f) of the Act.

Available information indicates that

both Imperial Valley, California, and

Nogales, Arizona, may qualify for

treatment under the International

Transport provision in section 179B of

the Act due to particulate matter

emanating from Mexico. While the

Agency has sufficient data at this time

to verify that PM-10 originating in

Mexico contributes to nonattainment in

these areas, additional monitoring and

air quality analysis are necessary to

quantify the international contribution

so that the SIP's for Nogales and

ImperiaLValley may accurately discount

international transport from their

attainment demonstrations, and EPA

can correspondingly determine whether

the SIP's for'the areas would be

adequate to attain and maintain the PM10 NAAQS but for emissions emanating

from Mexico (see section 179B of the

Act). The following is a more detailed

discussion of the areas affected by

international transport: Imperial Valley, California. The EPA

is not reclassifying the Imperial Valley

nonattainment area at this time.

Although the State of California has not

yet submitted a PM-10 SIP for Imperial

Valley, previous reports indicate that

transport from Mexicali, Mexico, may

significantly contribute to elevated PM10 levels in the Valley.' 2 As such, the

area may qualify for exclusion from

reclassification to serious under section

179B(d) of the Act.

On December 16, 1991, the EPA

Regional Administrator for Region IX

sent a letter to the Governor of

California notifying him of the State's

failure to submit a SIP for the Imperial

Valley. This notification started the 18-

month timeclock which will result in

the imposition of sanctions if EPA does

not receive a SIP [see section 179(a) of

the Act). The Imperial County Air

Pollution Control District is currently

working with the California Air

Resources Board (CARB) to develop a

PM-ia SIP for this area. The SIP is

scheduled to be submitted to EPA by the

2

"Draft Analysis of the Imperial County.

California Rural Fugitive Dust Area," prepared by

PE3 Associates, January 1989; "Example Level One

Air Quality Analysis for Particulate Matter State

Implementation Plan Revisions (Imperial Valley,

Cifornia)," State of California Air Resources

Board, March 1988; "Draft Program Plan for the

Imperial Valley/Mexicali Particulate Matter Sources

Apportionment Study." Desert Research Institute,

December 20, 1991.

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end of 1992. In addition, EPA and CARB

will be conducting a PM-10 source

apportionment study In the Imperial

Valley/Mexicali air basin in cooperation

with the Imperial County Air Pollution

Control District and the Secretary of

Social Development in Mexico. The

objectives of the study are to: (1)

estimate the spatial and temporal

distributions of PM-10 concentrations in

the Imperial Valley and Mexicali; (2)

apportion PM-10 concentrations to

source emissions; and (3) estimate crossborder transport of PM-10. The

monitoring portion of the study began

on March 10, 1992.

Nogales, Arizona. The EPA is not

taking final action to reclassify the

Nogales nonattainment area at this time.

Despite the fact that the State of Arizona

has not yet submitted a PM-10 SIP for

Nogales, previous studies by the

Arizona Department of Environmental

Quality indicate that transport from

Nogales, Mexico, may significantly

contribute to elevated PM-10 levels in

the nonattainment area. t3 As such, the

area may qualify for exclusion from

reclassification as serious under section

179B(d).

On December 16, 1991, the EPA

Regional Administrator for Region IX

sent a letter to the Governor of Arizona

notifying him of the State's failure to

submit a SIP for Nogales. This

notification started the 18-month

timeclock which will result in the

imposition of sanctions if EPA does not

receive a SIP [see section 179(a) of the

Act]. The Arizona Department of

Environmental Quality intends to

submit a SIP by the end of 1992. They

also planned to initiate a project in the

summer of 1992 to provide additional

emissions inventory data and source

contribution estimates for the Nogales

area.

The SIP's submitted for the remaining

5 areas contain control strategy

demonstrations purporting to show that

the NAAQS will be attained by

December 31, 1994. The Agency is

reviewing the public comments received

for these areas, as well as the SIP control

strategies and, as stated previously, will

make a determination concerning

reclassification upon taking rulemaking

action on the SIP's. Further discussion

of these areas follows below.

Klamath Falls, Oregon. Based upon

EPA's preliminary review of the PM-10

SIP submitted in response to the

November 15, 1991 SIP requirement,

EPA, at this time, supports the State's

""Preliminary Investigation of Causes and Extent

of the Nogales. Arizona PM-lO Problem." Arizona

Department of Environmental Quality. September 1990

determination that the nonattainment

area will practicably attain the NAAQS

by December 31, 1994. One comment

was received from the Oregon

Department of Environmental Quality

opposing reclassification. The

commenter asserted that the PM-10 SIP

submittal includes the necessary air

pollution control provisions and a

demonstration that attainment of the

NAAQS by December 31, 1994.

Libby, Montana. Based upon EPA's

preliminary review of the area's PM-10

SIP submitted in response to the

November 15, 1991 SIP requirement,

EPA, at this time, supports Montana's

determination that the Libby

nonattainment area will practicably

attain the NAAQS by December 31,

1994. The Montana Department of

Health and Environmental Sciences

submitted comments opposing

reclassification. The commenter

contended that the SIP contains an

adequate control strategy. including

point source permit modification, and

that it would be premature to reclassify

at this time.

Oglesby, Illinois. Based upon EPA's

preliminary review of the PM-10 SIP for

this area, EPA at this time supports the

State's determination that the

nonattainment area will practicably

attain the NAAQS by December 31.

1994. The EPA is currently evaluating

the SIP and will make a final

determination about reclassifying the

area because it cannot practicably attain

when EPA takes formalaction on the

submittal.

Paul Spur, Arizona. Based upon

EPA's preliminary review of the SIP

submitted for this area, EPA, at this

time, supports Arizona's determination

that the nonattainment area will

practicably attain the NAAQS by

December 31, 1994. The Arizona

Department of Environmental Quality

opposes reclassification based upon

EPA's design value criteria [see 56 FR

58658; Nov. 21, 19911 and its belief that

EPA should review the SIP before

deciding to reclassify the area. One

comment received from a private

corporation adds that significant

improvements to air quality have

already been made with the imposition

of control measures as indicated by the

data from 1988 through the third quarter

of 1991. Further control measures, the

commenter claims, are outlined In the

SIP revision.

Utah County, Utah. Following EPA's

preliminary review of the PM-10 SIP

submitted for this area in response to

the November 15, 1991 SIP requirement,

EPA, at this time, supports Utah's

determination that the nonattainment

area will practicably attain the NAAQS

by December 31, 1994. The State of

Utah's Department of Environmental

Quality opposes reclassification based

on its belief that the PM-10 SIP revision

provides for emissions reductions

sufficient to demonstrate attainment by

December 31, 1994. The commenter

states that EPA should be fair in giving

Utah County the opportunity to show

such attainment.

VI. Effect of Reclassification

Additional SIP revisions are required

under section 189(b) of the Act for the

nonattainment areas that are reclassified

to serious. First, regulations requiring

the use of best available control

measures (BACM), including "the

application of best available control

technology (BACT) to existing stationary

sources," must be adopted and

submitted to EPA within 18 months

after the area is reclassified to serious

[section 189(b)(2) of the Act]. '

4 The

BACM requirement must be

implemented within 4 years after the

area is reclassified [section 189(b)(1)(B)

of the Act]. Second, the State must

submit a SIP revision within 4 years

after reclassification of the area (within

18 months after reclassification for

failure to attain) that includes a

demonstration that the plan will attain

the PM-10 NAAQS by December 31,

2001 [see sections 188(c)(2),

189(b)(1)(A)(i), and 189(b)(2) of the

Act].15 Third, section 189(b)(3) of the

Act provides that "for any Serious Area,

the terms 'major source' and 'major

stationary source' include any stationary

source or group of stationary sources

located within a contiguous area and

under common control that emits, or

has the potential to emit, at least 70 tons

per year of PM-10." This provision

requires, among other things, smaller

new and modified sources (those with

the potential to emit 70tons per year or

greater, rather than 100 tons per year or

'

4As with RACM and RACT, BACT is a subset of

the overarching BACM requirement. The BACT

generally refers to the technological control

measures which apply to large stationary sources.

Thus. any reference to BACM herein implicitly

includes BACT.

Is Alternatively, the State must demonstrate that

attainment by December 31. 2001. is impracticable.

that the plan provides for attainment by the most

expeditious alternative date practicable (but no -

more than 5 years after the serious area attainment

date), and that the section 18a(e) of the Act

requirements for receiving an extension of the

attainmet date have been satisfied (i.e.. the plan

includes the most stringent measures that are

included in the implementation plan of any State or are achieved in practice in any State and can

feasibly be implemented in the area)lsee section 189

(b)(1)(A)(ii) of the Actl. Areas that are reclassified

under section 188(b)(2) of the Act following failure

to attain must submit attainment demonstarations

within 18 months after reclassification to serious

[see section 189(b)(2) of the Act].

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greater) to obtain section 172(c)(5) of the

Act construction permits which include

requirements to comply with lowest

achievable emission rates and to obtain

emission offsets [see sections 172(c)(5)

and 173 of Act].

Where an area is being reclassified to

serious, it may be reasonable for States

to consider the relationship of RACM to

BACM for the affected sources. The EPA

discussed this relationship in the

proposal for today's action (see 56 FR

58660-58661; Nov. 21, 1991). The EPA

anticipates that BACM for area sources

will generally be additive to or not

significantly incompatible with RACM

for these sources.' 6 Therefore, the

moderate area SIP's for the areas which

EPA is reclassifying should continue to

implement the requirements for the

application of RACM to appropriate

sources. After reclassification to serious,

additional regulations which require

BACM must be adopted and submitted

within 18 months and implemented

within 4 years, as stated above.

VII. Miscellaneous

A. Executive Orders

Under Executive Order 12291, EPA

has determined that this action is not "major" because reclassification of the

areas does not have an annual effect on

the economy of $100 million or more,

would not cause a major increase in

prices, and would not have a significant

adverse impact on competition or the

ability of United States enterprises to

compete with foreign enterprises. This

notice and the November 21, 1991

proposal were submitted to the Office of

Management and Budget (OMB) as

required by Executive Order 12291. Any

written comments from OMB and

written EPA responses to those

comments are included in the docket.

Similarly, any written comments from

OMB regarding today's final action, and

any written responses, have been placed

in the docket. This action does not

contain any information collection

requirements subject to OMB review

under the Paperwork Reduction Act of

1980 (44 U.S.C. sections 3501 et seq.),

A federalism assessment under

Executive Order 12612 is not requird

for this action since this action was

directed under section 188(b)(1)(A) of.

the Act.

B. Regulatory Flexibility Act

Under 5 U.S.C. section 605(b), the

Administrator has certified that

redesignations do not have a significant

economic impact on a substantial

number of small entities (see 46 FR

8709). BecaUse the regulatory Impact of

reclassifications under section 188(b) of

the Act is no different substantively

from, that associated with designations,

such actions are also not expected to

have significant impacts on small

entities.

List of Subjects in 40 CFR Part 81

Air pollution control, National parks.

Wilderness areas.

Dated: November 18, 1992.

William K. Reilly,

Administrator.

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 81.305 is amended by

revising the table for California--PM-10,

to read as follows:

§81.305 Calfornia. *t * t *t a

CALIFORNA.-PM-10. Nonattainment Areas

Designated area Designation Classification

Date Type Date Type

Inyo County Owens Valley planning area ................................................................................. 11/16/90 Nonattalnment 02/08/93 Serious.

Hydrologic Unit #18090103

San Bernardino, Inyo, and Kern Counties

Searles Valley planning area ............................................................... i .................. 11/16/90 Nonattalnment 11/15/90 Moderate.

Hydrologic Unit #18090205

Mono County Mammoth Lake planning area 1115/90 Nonattalnment 11/15/90 Moderate.

Includes the following sections: a. Sections 1-12, 17, and 18 of Township T4S, R28E;

b. Sections 25-38 of Township T3S, R28E; c. Sections 25-3 of Township T3S, R27E;

d. Sections 1-18 of Township T4S. R27E; and e. Sections 25 and 36 of Township T3S. R26E

Fresno. Kern. Kings, Tulare, San Joaquin. Stanislaus. Madera Counties

San Joaquin Valley planning area .......................................................................... 11/15/90 Nonattailnment 02/08/93 Serious.

Riverside, Los Angeles. Orange, and San Bernardino Counties

South Coast Air Basin .......................................................................................... 11/16/90 Nonattlnment 02/08/93 Serious.

Riverside County Coachella Valley planning area ............................................................................... 1115/90 Nonattalnment 02/8/93 Serious.

Imperial County Imperial Valley planning area .................................................................................. 1115/90 Nonattainment 1115/90 Moderate.

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

1

6The EPA also discussed the relationship

between RACM and BACM in the "General ' Preamble to Title I of the 1990 Clean Air Act

Amendments." 57 FR 13544 (April 16. 1992).

Specifically. EPA indicated that it may be

reasonable for States containing areas that will be

reclassified as serious to consider the compatibility

of RACM and RACT with BACM and BACT that

ultimately will be implemented under the serious

area plans for these areas. The EPA indicated that

States containing such areas need not require major

changes to control systems for specific stack and

process sources in the affected modeaes area SIP's

where they demonstrate ihat such changes will be

significantly incompltible with the application of

BACT-level control systems.

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* " 3. Section 81.329 is amended by 181.329 Nevad&

revising the table for Nevada-PM-10, - *

to read as follows:

NEVADA.-PM-10 NONATA#IMENT AREAS

Designated area Desgnation Cbmeat

OType TeDate T

Wi"ho Comty

Rena planning area ............. ........................................ 11/15/90 Nonattainment fl/ISO Modame.

Hyd ographic area 87

Clark County Las Vegas planning area ........................ li/sO tr feuw"nmnlt O2I08/93 Sedou.

Hydrographc Area 212

Rest of State ..................................................... ....... ....... . 11/15/M0 Uncla fable

* * * * *

[FR Doc. 93-375 Filed 1-7--93. 8.45 am]

BILLING CODE 6660-6"

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