40 CFR Part 52

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[MI19-01-5990; FRL-4999-2]

Disapproval of Clean Air Act PM Implementation Plan for Michigan

AGENCY: United States Environmental Protection Agency (USEPA).

ACTION: Notice of proposed rulemaking.

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SUMMARY: The USEPA today proposes disapproval of the State

Implementation Plan (SIP) submitted by the State of Michigan for the

purpose of bringing about the attainment of the National Ambient Air

Quality Standards (NAAQS) for particulate matter with an aerodynamic

diameter less than or equal to a nominal 10 micrometers (PM), because

USEPA finds unapprovable provisions in the consent orders submitted as

part of the SIP revision. The implementation plan was submitted by the

State to satisfy certain Federal requirements for an approvable

nonattainment area PM SIP for Wayne County, Michigan.

DATES: Comments on this proposed action must be received in writing by

July 15, 1994.

ADDRESSES: Comments should be addressed to: Carlton T. Nash, Chief,

Regulation Development Section, Air Toxics and Radiation Branch (AT-

18J), United States Environmental Protection Agency, Region 5, 77 West

Jackson Boulevard, Chicago, Illinois 60604-3590.

Copies of the State's submittal and other information are available

for inspection during normal business hours at the following location:

(It is recommended that you telephone Christos Panos at (312) 353-8328,

before visiting the Region 5 office.) United States Environmental

Protection Agency, Region 5, Air and Radiation Division, Air Toxics and

Radiation Branch, 77 West Jackson Boulevard, Chicago, Illinois 60604-

3590.

FOR FURTHER INFORMATION CONTACT: Christos Panos, Environmental

Engineer, Regulation Development Section, Air Toxics and Radiation

Branch (AT-18J), United States Environmental Protection Agency, Region

5, 77 West Jackson Boulevard, Chicago, Illinois 60604-3590, (312) 353-

8328.

SUPPLEMENTARY INFORMATION:

I. Background

Michigan was previously required to modify its particulate matter

SIP by the Clean Air Act Amendments of 1977. On May 22, 1981 (46 FR

27923), USEPA conditionally approved portions of Michigan's part D

Total Suspended Particulates (TSP) SIP. In response to USEPA's

conditional approval the Michigan Department of Natural Resources

(MDNR) submitted on May 17, 1985 revised rules, which were effective at

the State level on February 22, 1985 to control TSP from iron and steel

sources and from other sources in the State.

On August 7, 1987 (52 FR 29383), USEPA categorized areas of the

Nation into three groups based on the likelihood that protection of the

PM NAAQS would require revision of the existing SIP. The USEPA

identified the entire Wayne County, Michigan area as a PM ``Group I''

area of concern, i.e., an area with a strong likelihood of violating

the PM NAAQS and requiring substantial SIP revision. This Group I area

was reduced in size on October 31, 1990 and was subsequently designated

nonattainment for PM (55 FR 45799), and classified as moderate under

sections 107(d)(4)(B) and 188(a) of the Clean Air Act, upon enactment

of the Clean Air Act Amendments of 1990.1 See 56 FR 56694

(November 6, 1991).

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\1\The 1990 Amendments to the Clean Air Act made significant

changes to the Act. See Public Law No. 101-549, 104 Stat. 2399.

References herein are to the Clean Air Act, as amended (``the

Act''). The Clean Air Act is codified, as amended, in the U.S. Code

at 42 U.S.C. 7401, et seq.

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On June 11, 1992 (57 FR 24752), USEPA published a final rule which

approved certain sections of the State's May 17, 1985 submittal,

because the submittal represented an overall strengthening of the

existing Michigan SIP and would contribute to general improvement of

ambient air quality statewide, and disapproved other sections.

The amended Act required moderate PM nonattainment area SIP

submittals by November 15, 1991. On November 19, 1991 USEPA received

revisions to the Michigan SIP for the Wayne County PM nonattainment

area. The USEPA reviewed the submittal for completeness and found the

submittal to be incomplete. The USEPA made a finding pursuant to

section 110(k)(1)(C) of the Act that the State failed to submit a

complete SIP and notified the Governor in a letter dated December 17,

1991. See 57 FR 19906 (May 8, 1992). The USEPA's finding of

incompleteness activated the 18-month clock which could have resulted

in the imposition of sanctions pursuant to section 179 of the Act. On

June 11, 1993 the State submitted to USEPA new revisions for the Wayne

County PM nonattainment area SIP. The submittal was found to be

complete pursuant to section 110(k)(1) of the Act and USEPA notified

the State accordingly. This completeness determination corrected the

State's deficiency under section 179 of the Act and, therefore,

discharged the 18-month sanctions clock.

On April 7, 1994 the State submitted to USEPA a SIP revision for

the Marblehead Lime Company, River Rouge, Michigan. This submittal

supersedes the portion of the June 11, 1993 Wayne County PM

nonattainment area SIP submittal applicable to the Marblehead Lime,

River Rouge facility.

The air quality planning requirements for moderate PM nonattainment

areas are set out in subparts 1 and 4 of title I of the Act.2 The

USEPA has issued a ``General Preamble'' describing USEPA's preliminary

views on how USEPA intends to review SIP's and SIP revisions submitted

under title I of the Act, including those State submittals containing

moderate PM nonattainment area SIP requirements (see generally 57 FR

13498 (April 16, 1992) and 57 FR 18070 (April 28, 1992)). Because USEPA

is describing its interpretations here only in broad terms, the reader

should refer to the General Preamble for a more detailed discussion of

the interpretations of title I advanced in today's proposal and the

supporting rationale. In today's rulemaking action on the Michigan

moderate PM SIP, USEPA is proposing to apply its interpretations taking

into consideration the specific factual issues presented. Thus, USEPA

will consider any timely submitted comments before taking final action

on today's proposal.

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\2\Subpart 1 contains provisions applicable to nonattainment

areas generally and subpart 4 contains provisions specifically

applicable to PM-10 nonattainment areas. At times, subpart 1 and

subpart 4 overlap or conflict. EPA has attempted to clarify the

relationship among these provisions in the ``General Preamble'' and,

as appropriate, in today's notice and supporting information.

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Those States containing initial moderate PM nonattainment areas

were required to submit, among other things, the following provisions

by November 15, 1991:

1. Provisions to assure that reasonably available control measures

(RACM) (including such reductions in emissions from existing sources in

the area as may be obtained through the adoption, at a minimum, of

reasonably available control technology--RACT) shall be implemented no

later than December 10, 1993;

2. Either a demonstration (including air quality modeling) that the

plan will provide for attainment as expeditiously as practicable but no

later than December 31, 1994 or a demonstration that attainment by that

date is impracticable;

3. Quantitative milestones which are to be achieved every 3 years

and which demonstrate reasonable further progress (RFP) toward

attainment by December 31, 1994; and

4. Provisions to assure that the control requirements applicable to

major stationary sources of PM also apply to major stationary sources

of PM precursors except where the Administrator determines that such

sources do not contribute significantly to PM levels which exceed the

NAAQS in the area. See sections 172(c), 188, and 189 of the Act.

Some provisions were due at a later date. States with initial

moderate PM nonattainment areas were required to submit a permit

program for the construction and operation of new and modified major

stationary sources of PM by June 30, 1992 (see section 189(a)). Such

States also were to submit contingency measures by November 15, 1993

which become effective without further action by the State or USEPA,

upon a determination by USEPA that the area has failed to achieve RFP

or to attain the PM NAAQS by the applicable statutory deadline. See

section 172(c)(9) and 57 FR 13543-13544. These provisions will be

addressed in separate rulemaking actions.

II. In This Action

Section 110(k) of the Act sets out provisions governing USEPA's

review of SIP submittals (see 57 FR 13565-113566). In this action,

USEPA is proposing to disapprove the SIP revision submitted by the

State of Michigan to USEPA on June 11, 1993 which completed the

attainment plan for Wayne County, because it does not meet all of the

applicable requirements of the Act. The USEPA will consider any

comments submitted during the public comment period before taking final

action on today's proposal.

A. Analysis of State Submission

The State's June 11, 1993 submittal consisted primarily of 31

consent orders between the State and PM sources. The air quality

dispersion modeling conducted is based upon control measures,

limitations, and conditions contained in these orders. The USEPA is

proposing to disapprove the State's submittal because USEPA finds

unacceptable language in the consent orders submitted for approval into

the Michigan SIP. If the State removes the unacceptable language, or

replaces it with the previously approved version as detailed below, and

submits revised consent orders, the proposed disapproval will be

changed to an approval when USEPA takes final action on this submittal.

1. Procedural Background

The Act requires States to observe certain procedural requirements

in developing implementation plans and plan revisions for submission to

USEPA. Section 110(a)(2) of the Act provides that each implementation

plan submitted by a State must be adopted after reasonable notice and

public hearing.3 See also section 110(l) of the Act. The USEPA

also must determine whether a submittal is complete and therefore

warrants further USEPA review and action (see section 110(k)(1) and 57

FR 13565). The USEPA's completeness criteria for SIP submittals are set

out at 40 CFR part 51, appendix V (1991), as amended by 57 FR 42216

(August 26, 1991). The USEPA attempts to make completeness

determinations within 60 days of receiving a submission. However, a

submittal is deemed complete by operation of law if a completeness

determination is not made by USEPA 6 months after receipt of the

submission.

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\3\Also section 172(c)(7) of the Act requires that plan

provisions for nonattainment areas meet the applicable provisions of

section 110(a)(2).

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The State of Michigan held a public hearing on March 30, 1993 to

receive public comment on the implementation plan for the Wayne County

nonattainment area. Following the public hearing the plan was adopted

by the State and signed by the Governor's designee and submitted to

USEPA on June 11, 1993 as a proposed revision to the SIP.

The SIP revision was reviewed by USEPA to determine completeness

shortly after its submittal, in accordance with the completeness

criteria set out at 40 CFR part 51, appendix V (1991), as amended by 57

FR 42216 (August 26, 1991). The submittal was found to be complete and

a letter dated June 30, 1993 was forwarded to the Director, Michigan

Department of Natural Resources, indicating the completeness of the

submittal and the next steps to be taken in the review process. The

State's submittal of a complete SIP stopped the sanctions clock

triggered by USEPA's December 17, 1991 finding that Michigan's November

15, 1991 submittal was incomplete. As noted in today's action USEPA

proposes to disapprove the Michigan PM SIP submittal for Wayne County.

In addition, the State of Michigan held a public hearing on

February 16, 1994 to receive public comment on the implementation plan

revision for the Marblehead Lime Company, River Rouge, Michigan.

Following the public hearing the plan was adopted by the State and

signed by the Governor's designee and submitted to USEPA on April 7,

1994 as a proposed revision to the June 11, 1993 SIP submittal

applicable to the Marblehead Lime, River Rouge facility.

2. Emissions Inventory

Section 172(c)(3) of the Act requires that nonattainment plan

provisions include a comprehensive, accurate, current inventory of

actual emissions from all sources of relevant pollutants in the

nonattainment area. The emissions inventory should also include a

comprehensive, accurate, and current inventory of allowable emissions

in the area. Because the submission of such inventories are necessary

to an area's attainment demonstration (or demonstration that the area

cannot practicably attain), the emissions inventories must be received

with the submission (see 57 FR 13539).

The State provided thorough documentation of its emissions

estimates for all sources in the nonattainment area for a 1985 base

year. The Wayne County area was shown to include 31 facilities. The

allowable emission rates were calculated based on limits contained in

Michigan's part 3 Air Pollution Particulate Regulations, limits

contained in State permits, and limits contained in State consent

orders. Emissions from roadways and other area source types are

estimated in accordance with procedures specified in AP-42 and USEPA's

guidance document, ``Control of Open Fugitive Dust Sources'', using

inputs that are judged to provide reasonable estimates of these

emissions.

The significant sources in the nonattainment area are: (1) Stack

sources; (2) process fugitive emissions; and (3) area sources such as

roadways and storage piles. The majority of the facilities in the

nonattainment area were able to demonstrate attainment of the PM NAAQS

with RACT level of control. For facilities where this RACT level of

control was insufficient to demonstrate attainment, certain limits were

lowered, and various operating conditions were modified to secure

enough additional reductions to demonstrate attainment. Refinements to

existing fugitive dust plans were made according to the control

efficiencies predicted by USEPA's ``Open Fugitive Dust Source Computer

Model''. These emission limits, production limits, and fugitive dust

plans are incorporated into the consent orders submitted for approval

into the Michigan SIP. For further details see the Technical Support

Document (TSD).

The USEPA finds that the emissions inventory generally appears to

be accurate and comprehensive, and provides a sufficient basis for

determining the adequacy of the attainment demonstration for this area

consistent with the requirements of sections 172(c)(3) and 110(a)(2)(K)

of the Act.4

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\4\The EPA issued guidance on PM-10 emissions inventories prior

to the enactment of the Clean Air Act Amendments in the form of the

1987 PM-10 SIP Development Guideline. The guidance provided in this

document appears to be consistent with the Act.

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3. RACM (Including RACT)

As noted, the initial moderate PM nonattainment areas must submit

provisions to assure that RACM (including RACT) are implemented no

later than December 10, 1993 (see sections 172(c)(1) and 189(a)(1)(C)).

The General Preamble contains a detailed discussion of USEPA's

interpretation of the RACM (including RACT) requirement (see 57 FR

13539-13545 and 13560-13561).

The USEPA has previously judged that existing TSP regulations

applicable to point sources and contained in part 3 of Michigan's Air

Pollution Control Commission Rules provide for RACT and have already

been incorporated into the Michigan SIP (57 FR 24752, June 11, 1992).

The attainment needs of this area are such that additional measures as

provided in the current submittal may be considered reasonably

available. At the same time, further controls beyond those required in

the submittal and necessary for assuring attainment would not be

considered reasonable, unless those measures would provide for earlier

attainment. (See the General Preamble at 57 FR 13560).

For fugitive dust sources, generic RACT control efficiencies were

applied to potential emissions based on whether a facility had, and was

implementing, a fugitive dust plan submitted to and approved by the Air

Pollution Control Commission5. The generic RACT efficiencies and

their percent control, as recommended by the Wayne County Air Pollution

Control Division, are: unpaved roads and lots, 75 percent; paved roads

and lots, 35 percent; and storage piles and storage pile activities, 50

percent.

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\5\Michigan eliminated the Air Pollution Control Division in a

recent reorganization. MDNR now handles the responsibilities of the

former division.

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The USEPA has reviewed the State's explanation and associated

documentation and concluded that it adequately justifies the control

measures to be implemented. The consent orders in Michigan's submittal

provide for compliance by October 1, 1993 and the implementation of the

nonattainment plan control strategy will result in the attainment of

the PM NAAQS by December 31, 1994, therefore satisfying the

requirements of sections 172(c)(1) and 189(a)(1)(C) of the Act.

4. Demonstration of Attainment

As noted, the initial moderate PM nonattainment areas must submit a

demonstration (including air quality modeling) showing that the plan

will provide for attainment as expeditiously as practicable but no

later than December 31, 1994 (See section 189(a)(1)(B) of the Act).

Alternatively, the State must show that attainment by December 31, 1994

is impracticable.

The MDNR conducted an attainment demonstration using dispersion

modeling for the Wayne County nonattainment area. This demonstration

indicates that the NAAQS for PM will be attained by 1994 in Wayne

County and maintained in future years. The 24-hour PM NAAQS is 150

micrograms/cubic meter (g/m3), and the standard is

attained when the expected number of days per calendar year with a 24-

hour average concentration above 150 g/m3 is equal to or

less than one. See 40 CFR 50.6. The annual PM NAAQS is 50 g/

m3, and the standard is attained when the expected annual

arithmetic mean concentration is less than or equal to 50 g/

m3. The dispersion modeling in the demonstration predicted 146.3

g/m3 as the 24-hour design concentration, thus

demonstrating attainment of the 24-hour PM NAAQS. The dispersion

modeling in the demonstration predicted 49.5 g/m3 as the

annual design concentration, thus demonstrating attainment of the

annual PM NAAQS. The control strategy used to achieve these design

concentrations is summarized in the section titled ``RACM (including

RACT)''.

Several factors help assure that the Wayne County nonattainment

area will maintain as well as attain the standard. First, a substantial

majority of emissions in the area are from industrial sources and were

modeled either with maximum allowable emissions (for point sources) or

with emissions at the sources' full capacity operation (for area

sources). Thus, the only opportunities for growth in the inventory

beyond the modeled inventory are new source construction and growth in

public area sources. The new source review program assures that new

sources will not create violations of the air quality standards. For

public area source emissions, the Southeast Michigan Council of

Governments (SEMCOG) compiled estimates of daily vehicle miles traveled

(VMT) in Wayne County for a 1985 base year. To account for VMT growth

in Wayne County, SEMCOG reran their transportation models for the year

2005. The resulting VMT projections were compared to the 1985 base year

case and showed a net increase in PM emissions. The increase in

emissions, however, has already been accounted for in the attainment

demonstration. Michigan's modeling analysis, reflecting emissions in

2005, yielded a design value of 146.3 g/m3. Extrapolating

back to 1994 would yield a design value of 146.1 g/m3.

Therefore, the State of Michigan has demonstrated maintenance of the

air quality standard of 150 g/m3 through the year 2005.

See the TSD for a more detailed description of the attainment

demonstration and the control strategy used.

5. PM Precursors

The control requirements which are applicable to major stationary

sources of PM, also apply to major stationary sources of PM precursors

unless USEPA determines such sources do not contribute significantly to

PM levels in excess of the NAAQS in that area (see section 189(e) of

the Act).

An analysis of air quality and emissions data for the Wayne County

nonattainment area indicates that exceedances of the NAAQS are

attributable solely to direct PM emissions from stack sources, process

fugitive emissions, and area sources such as roadways and storage

piles, and not sources of PM precursors. Consequently, USEPA is

proposing to find that major sources of precursors of PM do not

contribute significantly to PM levels in excess of the NAAQS. The

consequences of this finding are to exclude these sources from the

applicability of PM nonattainment area control requirements. Note that

while USEPA is making a general finding for this area, today's finding

is based on the current character of the area including, for example,

the existing mix of sources in the area. It is possible, therefore,

that future growth could change the significance of precursors in the

area. The USEPA intends to issue future guidance addressing such

potential changes in the significance of precursor emissions in an

area.

6. Quantitative Milestones and Reasonable Further Progress (RFP)

The PM nonattainment area plan revisions demonstrating attainment

must contain quantitative milestones which are to be achieved every 3

years until the area is redesignated attainment and which demonstrate

RFP, as defined in section 171(1), toward attainment by December 31,

1994 (see section 189(c) of the Act). Reasonable further progress is

defined in section 171(1) as such annual incremental reductions in

emissions of the relevant air pollutant as are required by part D or

may reasonably be required by the Administrator for the purpose of

ensuring attainment of the applicable NAAQS by the applicable date.

As discussed in the General Preamble (57 FR 13539), attainment

plans for moderate areas which demonstrate attainment by December 31,

1994 will satisfy the initial quantitative milestone requirement. The

consent orders included in Michigan's SIP submittal require compliance

by October 1, 1993. Given this requirement and the fact that Wayne

County demonstrates attainment by 1994, USEPA believes the State's

submission clearly satisfies the initial quantitative milestone

requirement and demonstrates RFP.

7. Enforceability Issues

Sections 110(a)(2)(A) and 172(c)(6) of the Act, 42 U.S.C.

7410(a)(2)(A) and 7502(c)(6), require that each SIP include emission

limitations and other control measures, means or techniques, and

schedules or timetables for compliance which are enforceable by the

State and by USEPA. See also 57 FR 13556. In addition, States must

include in their nonattainment area SIPS a program to provide for the

enforcement of the measures described in the SIP. 42 U.S.C.

7410(a)(2)(C). The USEPA criteria addressing the enforceability of SIPs

and SIP revisions were provided in a September 23, 1987 memorandum

(with attachments) from Craig Potter, Assistant Administrator for Air

and Radiation, et al. (see 57 FR 13541).

The State of Michigan identified in its submittal particular

control measures for stack sources, process fugitive dust emissions,

and area sources such as roadways and storage piles. These control

measures are addressed in the section entitled ``RACM (including

RACT),'' above. In its submittal, the State specifies how each control

measure or limit is made enforceable. The majority of the control

measures are contained in the existing TSP regulations and, therefore,

are enforceable as part of the existing Michigan SIP. Some of the

control measures and applicable recordkeeping requirements,

particularly those dealing with area sources of PM, are contained in

the 31 consent orders which the State has requested that USEPA approve

as part of the Michigan SIP.

The USEPA finds the consent orders are not approvable as part of

the Michigan SIP for two reasons. First, each of the 31 consent orders

contains a provision (paragraph 11) which allows for the substitution

of ``equivalent'' particulate and fugitive dust control measures. The

consent orders provide that a company subject to an order may revise

the control programs contained in the order provided that, among other

things, neither MDNR nor USEPA objects to the revision within 45 days

of receipt of the proposal. The USEPA finds that this means of

modifying the control requirements contained in a consent order, which

would also (if approved) become part of the Michigan SIP, is

inappropriate because it bypasses the Act's substantive and procedural

requirements for SIP revisions. See sections 110(a)(2) and 110(i) of

the Act, 42 U.S.C. 7410(a)(2) and 7410(i).6

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\6\It should be noted that USEPA regulations promulgated

pursuant to title V of the Act contain provisions under which

alternative, equivalent emission limits may be incorporated in a

title V permit. See 40 CFR 70.6(a)(iii). However, these provisions

are applicable solely in the context of title V permits, and then

only if the specific requirements in that rule have been met. The

USEPA further notes that Michigan does not presently have a

federally approved title V program.

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By letter dated October 5, 1992 USEPA Region 5 informed MDNR that

it could provide sources some flexibility by revising paragraph 11 to

permit use of those measures specifically outlined in USEPA's PM-10

Open Fugitive Dust Source Computer Model Package (EPA-450/3-90-010).

More details on this mechanism are provided in the October 5, 1992

letter and USEPA's TSD. In its submission, however, Michigan did not

revise the orders to include this suggested approach.

Consistent with the above, if, during the public comment period,

MDNR revises paragraph 11 to delete the provision for substitution of

``equivalent'' measures, this portion of the consent orders may be

approved. In the alternative, MDNR may permit the use of the measures

identified in the Agency's fugitive dust model, in lieu of the

provision for substitution of ``equivalent'' measures, in accordance

with USEPA's October 5, 1992 letter.

In addition, each of the 31 consent orders provides for termination

upon the issuance of an operating permit pursuant to title V of the Act

(paragraph 12). Each title V operating permit, however, must include

all Clean Air Act provisions necessary to assure compliance with the

applicable requirements of the Act, including those in the SIP. See 42

U.S.C. 7661c(a). Therefore, the requirements contained in the title V

operating permit are to be those substantive requirements applicable

under other provisions of the Act, such as the SIP. For that reason,

the consent orders must not expire, even following issuance of the

operating permits.7 The TSD contains further information on the

enforceability of the consent orders.

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\7\The USEPA would not consider a valid termination of the

consent orders included in the SIP to have occurred unless and

until: The State issues a title V permit that contains the

provisions in the consent order; the State submits to USEPA a SIP

revision providing for replacement of the consent order with the

substitute permit; and USEPA approves the permit provisions as a SIP

revision.

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8. Ligninsulfonate Dust Suppressant

As stated earlier, MDNR used USEPA's ``Open Fugitive Dust Source

Computer Model'' to determine control efficiencies for various

combinations of chemical application rates and treatment frequencies

applicable to fugitive dust roadway emissions. The model lists watering

or chemical suppressants as two possible control options for unpaved

roads. Average efficiency curves were generated for four chemical dust

suppressants and, because there was little data available at the time,

the program was designed to be very general without any reference to a

specific chemical or brand name. The model allows for comparisons

between watering and chemicals, and between the chemicals originally

considered in the generation of the model, but not for the substitution

of suppressants other than the four types originally considered by the

model. Ligninsulfonate was not one of the four chemicals originally

evaluated by USEPA's model.

Ligninsulfonate has been utilized as a dust suppressant since the

early 1900's in Sweden and its use in this country dates to the 1940's.

Only one company in the nonattainment area (Levy, at five locations)

currently uses ligninsulfonate for dust suppression. The MDNR

investigated the relationship between the control efficiencies for

lignin suppressants relative to the ones considered in the computer

model to correlate the use of lignins to the use of the original four

suppressants. MDNR determined that if lignins are applied at a chemical

rate 2.3 times that of the chemicals considered in USEPA's computer

model, then the efficiency predicted by the model can be applied to

uncontrolled emission rates from unpaved roads being treated with

ligninsulfonate given equal treatment frequencies. The USEPA believes

that the data that has been submitted by the State of Michigan is

comparable to the original data used to determine the control

efficiencies of the dust suppressants included in the model, and,

therefore, is adequate to technically support the use of

ligninsulfonate as an alternative suppressant. See the TSD for further

details.

9. Contingency Measures

As provided in section 172(c)(9) of the Act, all moderate

nonattainment area SIP's that demonstrate attainment must include

contingency measures. See generally 57 FR 13543-13544. These measures

should consist of other available measures that are not part of the

area's control strategy and must take effect without further action by

the State or USEPA, upon a determination by USEPA that the area has

failed to make RFP or attain the PM NAAQS by the applicable statutory

deadline. As noted, States with initial moderate nonattainment areas

were not required to submit the contingency measures required in

section 172(c)(9), until November 15, 1993. The USEPA will determine

the adequacy of such submittal as appropriate in a separate rulemaking.

III. Implications of This Action

The USEPA is proposing to disapprove in its entirety the SIP

revision submitted by the State of Michigan on June 11, 1993 for the

Wayne County PM nonattainment area because USEPA finds unapprovable

provisions in each of the 31 consent orders submitted as part of the

SIP revision. If the State removes the unacceptable language in

paragraph 11, or replaces it with the previously approved version

mentioned above, and removes paragraph 12 in each of the 31 consent

orders, and submits revised consent orders which USEPA finds

acceptable, the proposed disapproval would be changed to an approval

when USEPA takes final action on this submittal. If finalized, this

disapproval would constitute a disapproval under section 179(a)(2) of

the Act (see generally 57 FR 13566-13567). As provided under section

179(a) of the Act, the State of Michigan would have up to 18 months

after a final SIP disapproval to correct the deficiency that is the

subject of the disapproval before USEPA is required to impose either

the highway funding sanction or the requirement to provide two-to-one

new source review offsets. If the State has not corrected its

deficiency within 6 months thereafter, USEPA must impose the second

sanction. Any sanction USEPA imposes must remain in place until USEPA

determines that the State has come into compliance.

IV. Request for Public Comments

The USEPA is requesting comments on all aspects of today's

proposal, including USEPA's proposed decision to impose the two to one

new source review offset requirement as the first sanction should USEPA

ultimately disapprove this submittal in whole or in part and the State

fails to timely remedy the deficiency. As indicated at the outset of

this document, USEPA will consider any comments received by July 15,

1994.

V. Executive Order 12866

This action has been classified as a Table 2 action by the Regional

Administrator under the procedures published in the Federal Register on

January 19, 1989 (54 FR 2214-2225), as revised by an October 4, 1993

memorandum from Michael H. Shapiro, Acting Assistant Administrator for

Office of Air and Radiation. A future document will inform the general

public of these tables. On January 6, 1989 the Office of Management and

Budget (OMB) waived Table 2 and 3 SIP revisions (54 FR 2222) from the

requirements of section 3 of Executive Order 12291 for 2 years. The

USEPA has submitted a request for a permanent waiver for Table 2 and 3

SIP revisions. The OMB has agreed to continue the waiver until such

time as it rules on USEPA's request. This request continues in effect

under Executive Order 12866 which superseded Executive Order 12291 on

September 30, 1993. OMB has exempted this regulatory action from E.O.

12866 review.

VI. Regulatory Flexibility

Under the Regulatory Flexibility Act, 5 U.S.C. 600 et seq., USEPA

must prepare a regulatory flexibility analysis assessing the impact of

any proposed or final rule on small entities. 5 U.S.C. 603 and 604.

Alternatively, USEPA 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.

The USEPA's disapproval of the State request under section 110 and

subchapter I, part D of the Act does not affect any existing

requirements applicable to small entities. Any pre-existing Federal

requirements remain in place after this disapproval. Federal

disapproval of the State submittal does not affect its state-

enforceability. Moreover, USEPA's disapproval of the submittal does not

impose any new Federal requirements. Therefore, USEPA certifies that

this disapproval action does not have a significant impact on a

substantial number of small entities because it does not impose any new

Federal requirements.

List of Subjects in 40 CFR Part 52

Environmental protection, Air pollution control, Intergovernmental

relations, Particulate matter, Reporting and recordkeeping

requirements.

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

Dated: June 2, 1994.

Michelle D. Jordan,

Acting Regional Administrator.

[FR Doc. 94-14538 Filed 6-14-94; 8:45 am]

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