,' . !. UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

Office of Air Quality Planning and Standards 

Research Triangle Park, North Carolina 2771 1 

NOV 14 1994 

'SUBJECT: Criteria.for Granting l-Year Extensions of Moderate 

PM-10 Nonattainment Area Attainment Datea, Making 

~ttainment Determinations, and Reporting - on - - 

FROM : 

Air Quality Strategies and Standarde Division (MD-15) ' 

TO : Di~ector, Air, Peaticides and Toxics 

Management Division, Regions I and IV 

Director, Air and Waste Mariagement.Division, 

Region I1 

Director, Air, Radiation and Toxics Division, 

~egion III 

Director, Air and Radiation Division, 

Region V 

Director, Air, Pesticides and Toxies Division, 

Region VI 

Director, Air and Toxice Division, 

Region8 VII, VIII, IX, and X 

Pursuant to sections 179 (c) and 188 (b) (2) of the Clean Air 

Act,= the Administrator is to determine whether a nonattainment 

area has attained the PM-10 NAAQS by the applicable attainment 

date. The purpose of this memorandum ie to provide the EPA 

Regional Office8 and the State air pollution control agepciea 

with the relevant criteria for making attainment determinations, 

to provide information on the criteria for granting attainment 

date extension8 for moderate PM-10 nonattainment areas, and to 

implement quantitative milestone requiremente.' 

xThe Clean Air Act is codified, as amended, at 42 U.S.C. 

7401, et seq. 

'The policies set out in this memorandum are intended solely 

as guidance, do not represent final action, and are not ripe for 

judicial review. They are not intended to bind the States and 

(continued . . .I 
Backsround 

The EPA has general authority to designate areas which 

violate the PM-10 NAAQS as nonattainment pursuant to section . 

107(d) of the Act.. Upon designation as nonattainment, these 

areas are classified, by operation of law, as "moderateu 

nonattainment areas [see section 188(a) of the Act]. 

On the date of enactment of the 1990 Clean Air Act 

Amendments, PM-10 areas meeting the qualifications of section 

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

operation of law. These areas'included all former group I areas 

identified in 52 FR 29383 (August 7, 1987) and further clarified 

in 55 FR 45799 (October 31, 1990) any other areas violating the 

PM-10 NAAQS prior to January 1, 1989. All other areas were 

designated unclassifiable [see section 107(d) (4) (B) (iii) of the 

Act]. The EPA may redesignate any of these unclassifiable areas 

as nonattainment in accordance with section 107(d) (3) of the Act. 

States with areas which have been redesignated as 

nonattainment for PM-10 have the responsibility of developing and 

submitting to EPA a SIP which addresses the nonattainment air 

quality problem in the area. The EPA issued a "General Preamblew 

describing EPAts preliminary views on the interpretation of 

various SIP requirements, including those requirements applicable 

to moderate PM-10 nonattainment areas.3 Sections 172 (c) and 

189(a) of the Act outline some of the most important elements 

which must be contained in the SIP. Among these elements is the 

requirement to submit a SIP revision that provides for the 

implementation of reasonably available control measures (RACM) 

[including reasonably available control technology (RACT)].4 

States containing initial moderate PM-10 nonattainment areas 

were required to submit SIP'S containing RACM by 

November 15, 1991, and these SIP'S were required to provide for 

the implementation of RACM no later than December 10, 1993.5 

2 ( . . . continued) 

preliminary views, and EPA may modify this guidance at any time 

or act at variance with the guidance based upon analysis of 

specific circumstances. 

3See generally, 57 FR 13498 (April 16, 1992) and 57 FR 18070 

(April 28, 1992) . 

4All references to RACM in this document include RACT, which 

is a subset of the RACM requirement. 

'Initial nonattainment areas were those areas designated 

nonattainment under section 107 (dl (4) (B) of the Act. These areas 

(continued. . . ) 
Affected States are required to demonstrate attainment of the 

PM-10 NAAQS in these areas as expeditiously as practicable, and 

no later than December 31, 1994, or demonstrate that timely 

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

189 (a) (1) (B) of the Act] . 

States containing areas redesignated as moderate PM-10 

nonattainment areas subsequent to the 1990 Amendments are 

required to submit SIP'S for these areas containing RACM no later 

than 18 months after redesignaFion [see section 189(a) (2) (B) of 

the Act]. The SIP revisions are required to provide for the 

implementation of RACM no later than 4 years after redesignation 

as nonattainment [see section 189 (a) (1) (C) of the Act] . These 

SIP'S were required to demonstrate attainment of the PM-10 NAAQS 

as expeditiously as practicable, but no later than the end of the 

sixth calendar year after redesignation as nonattainment or to 

demonstrate that timely attainment is impracticable [see sections 

188 (c) (1) and 189 (a) (1) (B) of the Act] . 

Overview of the Policv 

I. Backsround 

The Administrator must determine whether PM-10 nonattainment 

areas have attained the NAAQS within 6 months of the applicable 

attainment date, and the State must report on the quantitative 

milestones for the area within 90 days of the milestone date for 

the area. The attainment date for the initial PM-10 

nonattainment areas is December 31, 1994. 

11. Attainment determination 

A. Attainment determination will be based upon whether 

an area has 3 consecutive vears of clean air quality data. This 

determination will be made in accordance with EPA as prescribed 

under 40 CFR part 50, appendix K. 

B. Any discrepancies with the data will be resolved in 

accordance with 40 CFR part 50, appendix K, during the process of 

reviewing the data. 

5 ( . . . continued) 

were required to implement RACM no later than December 10, 1993, 

pursuant to section 189 (a) (1) (C) of the Act. 
111. Criteria for obtainins an extension of the attainment date 

for moderate - areas 

A. The area must have no more than one measured exceedance 

at any monitoring site in the nonattainment area in the year 

preceding the extension year. 

B. The State must demonstrate that it is complying with all 

requirements that pertain to the area in the s~licable SIP. The 

applicable SIP is the latest federally-approved particulate 

matter SIP for the nonattainment area [see section 302(q) of the 

Act] . 

C., The EPA will request additional information from States 

to make its decision on whether to grant an attainment date 

extension. The EPA will be disinclined to grant an attainment 

date extension unless the State can substantially demonstrate 

that certain information concerning the Act planning requirements 

have been completed. The EPA will expect the State to 

demonstrate that: 

1. Control measures have been submitted in the form of a 

SIP revision and substantially implemented to satisfy the 

RACM/RACT requirement for the area. 

2. The area has made emission reduction progress that 

represents reasonable further progress toward timely attainment 

of the PM-10 NAAQS. 

IV. Conseauences of failure to attain or qualify for an 

extension 

A. The consequence of an area failing to attain the 

standard or qualify for an extension of the attainment date is 

that the area will be reclassified to serious by operation of law 

[see section 188 (b) (2) of the Act] . In addition, contingency 

measures must be implemented in any area which fails to attain 

the standard by the applicable attainment date. 

B. Upon reclassification, the State must meet the planning 

requirements for serious PM-10 nonattainment areas. These 

requirements include, among other things, provisions for the 

implementation of best available control measures (BACM) no later 

than 18 months from the date of reclassification. 

C. The Regional Offices will prepare the Federal Resister 

notices that identify the areas which will be reclassified to 

serious or will be granted an extension of the attainment date. 

These determinations will be announced in the Federal Resister 

following notice and comment rulemaking procedures. 
1. The EPA Headquarters will draft the Federal Resister 

notice identifying the areas which have attained the standard. 

V. Quantitative emission reduction milestones and reasonable 

further prosress 

A. The PM-10 nonattainment plan revisions demonstrating 

attainment must provide for quantitative emission reduction 

milestones which must be achieved every 3 years until the area is 

redesignated attainment and which demonstrate reasonable further 

progress for the area. 

1. The State should address at least the first two 

milestones along with the moderate area SIP. 

a. The first milestone is the emission reduction progress 

made between the SIP submittal and the attainment date for the area. 

b. The second milestone should provide for maintenance to 

ensure that the area remains in attainment after the attainment 

date. 

2. The PM-10 nonattainment areas must provide for 

quantitative emission reduction milestones which must be achieved 

every 3 years and which demonstrate reasonable further progress 

until the area is redesignated to attainment. 

B. Within 90 days of the date on which the milestone for a 

nonattainment area occurs, each State in which all or part of 

such nonattainment area is located must submit a milestone report 

to EPA. This report must demonstrate that all of the measures in 

the SIP approved under section 189 of the Act have been 

implemented, that the milestone for the area has been met, and 

that reasonable further progress has been achieved. Thus, EPA 

has broad discretion in determining the manner of the submittal 

and the information contained in the submittal (see the detailed 

discussion concerning milestone reporting). 

VI. . Requests for redesisnation to attainment 

A. If an area is determined to have attained the PM-10 

NAAQS by the attainment date, the area will remain nonattainment 

until all five of the requirements under section 107(d) (3) (E) of 

the Act have been met. Among the requirements of section 

107 (d) (3) (E) is that the State submit, and EPA approve, a SIP 

revision which satisfies the requirements of the 1990 Amendments. 

The rationale for the above policy statements are discussed in 

detail in the following actions. 
Determination of Attainment 

The EPA has the responsibility for determining whether a 

nonattainment area has attained the PM-10 NAAQS by the applicable 

attainment date.6 The EPA must make an attainment determination 

for the initial moderate nonattainment areas by June 30, 1995, no 

later than 6 months after the attainment date for the area.7 

The Act also requires EPA to publish a notice in the Federal 

Resister identifying those areas which failed to attain and 

reclassifying those areas as useriousv nonattainment areas. 

The EPA will be making attainment determinations for 

nonattainment areas based solely upon an area's air quality data, 

and no special or additional SIP submittal will be required from 

the State for this determination. Section 179(c) (1) of the Act 

provides that the attainment determination is to be based upon an 

area's "air quality as of the attainment date. The EPA will 

make the determination of whether an area's air quality is 

meeting the PM-10 NAAQS by the applicable attainment date based 

upon data gathered from air quality monitoring sites which have 

been entered into the Aerometric Information Retrieval System 

(AIRS) data base. 

A PM-10 nonattainment area's air quality status is 

determined in accordance with appendix K of 40 CFR part 50. 

Attainment of the annual PM-10 standard is achieved when the 

annual arithmetic mean PM-10 concentration is equal to or less 

than 50 kg/m3. Attainment of the 24-hour PM-10 standard is 

determined by calculating the expected number of exceedances of 

the 150 pg/m3 limit per year. The 24-hour standard is attained 

when the expected number of exceedances is 1.0 or less. A total 

of 3 consecutive years of clean air quality data is generally 

necessary to show attainment of the 24-hour and annual standard 

for PM-10. A complete year of air quality data, as referred to 

6~ee sections 179 (c) and 188 (b) (2) of the Act. 

7~n some cases, States may choose to submit moderate area 

SIP'S which include requests for redesignation to attainment 

before the applicable attainment date. In these cases, if EPA 

finds the SIP'S to be approvable, the SIP'S will be promulgated 

in the Federal Resister. The EPA will make a determination of 

attainment for the area no later than 6 months after promulgation 

of the SIP approval in the Federal Resister. This determination 

will be made in accordance with 40 CFR part 50, appendix K. The 

EPA will grant those requests for redesignation to attainment 

which satisfy all of the requirements of section 107(d) (3) (E) of 

the Act. 
in part 50, appendix Kt is comprised of all 4 calendar quarters 

with each quarter containing data from at least 75 percent of the 

scheduled sampling days.' 

The EPA will begin processing and analyzing data related to 

the attainment of PM-10 areas immediately aft-er the applicable 

attainment date for the affected areas. Current EPA policy, 

pursuant to 40 CFR part 58, sets the deadline for submittal of 

air quality data into the AIRS data base for no later than 90 

days after the end of the calendar year. In order for EPA to 

determine the attainment status of PM-10 areas, EPA must review 

the data for the 3 years prior to the attainment date for the 

areas. Due to the schedule for making attainment determinations, 

pursuant to sections 179 (c) (2) and 188 (b) (21, States should 

submit the required air quality data for the year preceding the 

attainment date into the AIRS data base as expeditiously as 

practicable, but no later than 90 days after the attainment date 

for the area. States should identify any issues concerning the 

validity of the data or discrepancies related to the data during 

this time period. The EPA will address issues related to the 

adequacy of data on a ,~ase-by-case babis in accordance with 40 

CFR part 50, appendix Rr- /' 

Section 179 (c) (2) of the Act also states that EPA may revise 

or supplement the attainment determination at any time based upon 

more complete information or analysis concerning the area's air 

quality as of the attainment date. The EPA interprets this to 

mean that in cases where there are discrepancies concerning the 

data or the validity of the data revealed subsequent to an 

attainment determination, EPA may later address these issues in 

accordance with EPA guidance as stated in 40 CFR part 50, 

appendix K. 

'under 40 CFR 50.6(a), the 24-hour primary and secondary 

standards are attained when the expected number of exceedances 

per year at each monitoring site is less than or equal to one. 

In the simplest case, the number of exceedances at a site is 

determined by recording the number of exceedances in each 

calendar year and then averaging them over the past 3 calendar 

years. Under 40 CFR part 58.13, the minimum percentage of 

monitoring data which can be considered as sufficient to 

determine attainment for PM-10 at any given monitoring site is 75 

percent. The amount of data required varies with the sampling ---, - frequency, data capture rate, _ and tfi%-Gnumber of year-s,.gecorded at 

a monitoring site. More- tKan 3 years of data may be considered 

if all additional rep5esentative years of data meeting the %?+ 

percent criterion are utilized. Data not meeting this criteri "\a 

may also suffice to show attainment; however, such exceptions 

must be approved by the appropriate Regional Administrator i 

2.0-2.3). / 

- . - --- -- 

accordance with EPA guidance (see part 50, appendix 

-. -- 
While EPA may determine that an area's air quality data 

indicate that the area may be meeting the PM-10 NAAQS for a 

specified period of time, this does not eliminate the State's 

responsibility under the Act to adopt and implement an approvable 

SIP. If EPA determines that an area has attained the standard, 

the area will remain classified as nonattainment until the State 

has requested, and EPA has approved, redesignation to attainment 

for the area. 

In order for an area to be redesignated as attainment, the 

Sta-te must comply with the five requirements listed under section 

107 (dl (3) (El of the Act. Among other things, section 

107 (dl (3) (El requires that EPA determine that an area has met the 

PM-10 NAAQS and that the State has submitted a SIP which has been 

approved by EPA.' 

Attainment Date Extension Criteria for Moderate 'Areas 

If a State containing a moderate PM-10 nonattainment area 

does not have 3 consecutive years of clean air quality data to 

demonstrate that the area has attained the PM-10 NAAQS, the State 

may apply for a 1-year extension of the attainment date. The EPA 

may extend the attainment date for 1 year only if the State 

submits an application for the affected nonattainment area 

satisfying all of the following requirements: 

1. The area must have no more than one exceedance of the 

24-hour PM-10 NAAQS in the year preceding the extension year and 

the annual mean concentration of PM-10 in the year preceding the 

extension year must be less than or equal to the PM-10 NAAQs.~' 

Data requirements for purposes of making comparisons with the 

24-hour and annual PM-10 NAAQS must be consistent with section 

2.3 of 40 CFR part 50, appendix K. 

'see "Procedures for Processing Requests to Redesignate 

Areas to Attainment" memorandum to Regional Air Directors from 

John Calcagni, Director of the Air Quality Management Division, 

September 4, 1992. 

'O~he Act states that no more than one exceedance may have 

occurred in the area [see section 189 (d) (2) I . The EPA interprets 

this to prohibit extensions if there is more than one measured 

exceedance of the 24-hour standard at any monitoring site in the 

nonattainment area. The number of exceedances will not be 

adjusted to expected exceedances as long as the minimum required 

sampling frequencies have been met. 
2. The State must demonstrate that it has complied with all 

requirements and commitments pertaining to the affected 

nonattainment area in the applicable implementation plan.'' 

Requirements and commitments in the "applicable implementation 

plan" include SIP revisions approved by EPA under section 110(k) 

of the Act and FIPts promulgated by EPA under section 110(c) (1) 

of the Act [see section 302(q) of the ~ctl* [see generally 

section 188 (dl of the Act] . 

The authority delegated tg the Administrator to extend 

attainment dates for moderate qreas is discretionary. section 

188 (d) of the Act provides that the Administrator "mayff extend 

the attainment dat.e for areas that meet the minimum requirements 

specified above. The provision does not dictate or compel that 

EPA grant extensions to such areas. 

In exercising this discretionary authority for PM-10 

nonattainment areas, EPA will examine the air quality planning 

progress made in the moderate area. In addition to the two 

criteria specified in section 188(d), EPA will be disinclined to 

grant an attainment date extension unless a State has, in 

substantial part, addressed its moderate PM-10 planning 

obligations for the area. While States are encouraged to take 

expeditious steps toward completing SIP revisions which satisfy 

the requirements of the Act, Federal approval of PM-10 SIP 

requirements is not required in order to be granted an attainment 

date extension. The EPA, however, will expect the State to have 

adopted and substantially implemented control measures submitted 

to address the requirement for implementing RACM/RACT in the 

moderate nonattainment area, the central control requirement that 

applies to such areas.13 

The EPA believes that requesting the State to demonstrate 

that control measures have been adopted and are being implemented 

for areas seeking an extension is a reasonable expectation 

because the implementation of the control measures is an 

 he PM-10 SIP revisions required under the 1990 Amendments 

are not included in the definition of "applicable implementation 

planu if EPA has not taken final rulemaking action to approve the 

revisions. 

12states were required to submit PM-10 SIP revisions for 

initial moderate nonattainment areas on November 15, 1991. In 

the instances where EPA will not have taken final rulemaking 

action on the State's moderate area SIP revision prior to 

granting the attainment date extension for the area, the 

applicable SIP for the area would be the most recent federallyapproved particulate matter SIP for the area. 

, 13see sections 172 (c) (1) and 189 (a) (1) (C) of the Act. 
appropriate indication that the improvement in air quality, 

evidenced by the low number of exceedances, reflects the 

application of permanent steps to improve the air quality, rather 

than temporary economic or meteorological changes. As a part of 

this showing, EPA will expect the State to demonstrate that the. 

PM-10 nonattainment area has made emission reductions amounting 

to reasonable further progress toward attainment of the PM-10 

NAAQS as defined in section 171(1) of the Act. 

In order to demonstrate that the control measures have been 

adopted and are being implemented, and that reasonable further 

progress is being met, the State must submit an application for 

an attainment date extension in the form of a report similar to 

the quantitative emission reduction milestone report discussed 

below. (See section below on the criteria for the quantitative 

emission reduction milestone report.) This report may be 

submitted to EPA by the governor or his/her designee no later 

than 90 days after the attainment date for the area. The EPA 

Regional Offices will address a State's request for a 1-year 

extension of the attainment date through the comment and 

rulemaking process no later than 6 months after the applicable 

attainment date. If the State cannot make a sufficient 

demonstration that the area has complied with the extension 

criteria stated above, and EPA determines that the area has not 

timely demonstrated attainment of the PM-10 NAAQS, the area will 

be reclassified as serious by operation of law pursuant to 

section 188 (b) of the Act. 

If an extension is granted at the end of the extension year, 

EPA will again determine whether the area has attained the PM-10 

NAAQS. If the requisite 3 consecutive years of clean air quality 

data needed to demonstrate attainment are not met, the State may 

apply for a second 1-year extension of the attainment date. In 

order to qualify for the second 1-year extension of the 

attainment date, the State must satisfy the same requirements 

listed above for the first extension. In addition, EPA will 

consider the State's PM-10 planning progress for the area similar 

to its evaluation of the first extension request. However, EPA 

may grant no more than two 1-year extensions of the attainment 

date to a single nonattainment area [see section 188(d) of the 

Act]. 

Conseauences for Moderate Areas that Fail to Timelv Attain the 

PM-10 NAAQS 

The discussion which follows addresses the consequences of 

EPA's determination that a moderate area has failed to timely 

attain the PM-10 NAAQS. The consequences described below apply 

with equal force to moderate areas that fail to attain the PM-10 

NAAQS by the initial attainment date, that are not granted 

extended attainment dates, or that fail to meet an extended 

attainment date. 
If EPA finds that a moderate area is not in attainment after 

the applicable attainment date, the area will be reclassified by 

operation of law as a serious PM-10 nonattainment area.14 The 

EPA Regional Offices will identify the areas that have failed to 

attain the PM-10 NAAQS and reclassify them as serious, through 

the notice and comment rulemaking process in the Federal 

Resister, no later than 6 months following the attainment date. 

For efficiency, the Regional Offices may also choose to identify 

those areas which have been granted a 1-year extension of the 

attainment date in the same Federal Resister notices. 

Within 18 months after reclassification of an area as 

serious nonattainment, the affected States must submit, among 

other requirements, SIP'S containing provisions to assure that 

best available control measures (including best available control 

technology) are implemented no later than 4 years after 

reclas~ification.~~ Inaddition, contingency measures must take 

effect upon a determination by EPA that an area has failed to 

timely attain the PM-10 NAAQs.~~ Moderate area plans are 

required to provide for the implementation of specific measures 

to be undertaken if the area fails to make reasonable further 

progress, or to attain the NAAQS by the applicable attainment 

date. Such measures are to be included in the plan as 

contingency measures to take effect without further action by the 

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

failed to achieve reasonable further progress, or to timely 

attain the NAAQS. 

For the initial moderate nonattainment areas, EPA 

established November 15, 1993 as the due date for submission of 

contingency'measures [see General Preamble (57 FR 13543), 

April 16, 1992)l. The General Preamble contains significant 

guidance about the implementation of the contingency measure 

requirement.17 The EPA is currently developing further guidance 

on contingency measures which will be forwarded to the States and 

Regional Offices at a later date. 

The EPA interprets the requirement that contingency measures 

"take effect . . . without further action by the State, or [EPA] 

to mean that no further rulemaking activities by the State or EPA 

14See section 188(b) (2) of the Act. 

''see section 189(b) of the Act and 59 FR 41998 [August 16, 

1994 (guidance on serious PM-10 nonattainment area SIP 

requirements including BACM) I . 

16see section 172 (c) (9) of the Act. 

17see 57 FR 13510 and 13543-44. 
would be needed to implement the contingency measures.'' In 

general, EPAwill expect all actions needed to affect full 

implementation of the measures to occur within 60 days after EPA 

notifies the State of its failure to attain the standard. 

Contingency measures have not been submitted for several of 

the initial moderate PM-10 nonattainment areas. The EPA made 

findings of failure to submit for these areas in January of 1994. 

States which failed to submit contingency measures have 18 months 

to correct this deficiency before sanctions must be imposed [see 

section 179 of the Act and 59 FR 39832 (August 4, 1994)l. 

Quantitative Emission Reduction Milestones and Reasonable Further 

Prosress 

VII. Milestone submittals 

The PM-10 nonattainment area SIP'S demonstrating attainment 

must include quantitative emission reduction milestones which are 

to be achieved every 3 years until the area is redesignated 

attainment and which demonstrate reasonable further progress, as 

defined in section 171(1) of the Act, toward timely 

attainment.lg The EPA has issued general guidance on the 

implementation of this requirement for moderate PM-10 

nonattainment areas as well as for serious PM-10 nonattainment 

areas. 20 

The Act does not clearly indicate the starting point for 

counting the first 3-year period or how many milestones must be 

initially addressed. In the General Preamble, EPA addressed the 

statutory gap in the starting point for counting the 3-year 

milestones, indicating that it would begin from the due date for 

the SIP revision containing the control measures for the area, 

i.e., November 15, 1991 for initial moderate PM-10 nonattainment 

areas (see 57 FR 13539). 

Section 189(c) plainly provides that quantitative milestones 

are to be achieved "until the area is redesignated attainment." 

However, this endpoint for quantitative milestones is speculative 

because redesignation of an area as attainment is contingent upon 

several factors and future events. The EPA believes that it is 

unreasonable to require planning for each nonattainment area to 

cover quantitative milestones several years into the future based 

''see section 172 (c) (9) of the Act and 57 FR 13512. 

Igsee section 189(c) of the Act 

20See 57 FR 13539 for the PM-10 moderate area guidance on 

milestones .and 59 FR 41998 for guidance on milestones for serious 

nonattainment areas. 
on the possibility that such time may elapse before an area is in 

fact redesignated to attainment. On the other hand, EPA believes 

that it is reasonable for States initially to submit a number of 

milestones sufficient to ensure that there is ongoing air quality 

protection beyond the attainment deadline. This will help to 

ensure that areas timely attaining the PM-10 NAAQS do not fall 

out of attainment before qualifying for redesignation. 

The EPA believes that at least two milestones should 

initially be addressed. Thus, submittals to address the SIP 

revisions due on November 15, 1991 for the initial moderate PM-10 

nonattainment areas should have demonstrated that, at a minimum, 

the following two milestones will be achieved: (1) First 

milestone--November 15, 1991 through November 15, 1994; and 

(2) second milestone--November 15, 1994 through November 15, 

1997. In all instances, additional milestones must be addressed 

and submitted at 3-year intervals if an area is not redesignated 

attainment. 

The EPA has previously indicated that for the initial PM-10 

moderate nonattainment areas that demonstrate timely attainment 

of the PM-10 NAAQS, the emission reduction progress made between 

the SIP submittal (i-e., due date of November 15, 1991) and the 

attainment date (i.e., no later than December 31, 1994) will ' 

satisfy the first quantitative milestone.21 For areas that 

demonstrate timely attainment of the PM-10 NAAQS, the milestones 

beyond the attainment date should, at a minimum, provide for . continued maintenance of the standards. The EPA intends to 

provide further guidance at a later date concerning the 

application of quantitative milestones and reasonable further 

progress for moderate nonattainment areas which demonstrate that 

attainment by the applicable attainment date is not practicable. 

Those moderate nonattainment areas designated subsequent to 

enactment of the 1990 Amendments will similarly be expected to 

initially submit two milestones. States are required to submit 

SIP'S for these areas 18 months after their redesignation as 

n~nattainment.~~ The attainment date for new PM-10 

nonattainment areas is "as expeditiously as practicable" but no 

later than the end of the sixth calendar year after an area's 

designation as n~nattainment.~~ 

21~ee 57 FR 13539. 

22See section 189 (a) of the Clean Air Act. 

23~ee section 188 (c) (1) of the Act. 
Because the SIP revision, including the quantitative 

milestone submittal, for a new nonattainment area is due 18 

months after the area is designated as nonattainment, the first 

3-year milestone is to be achieved 4 1/2 years after the 

nonattainment redesignation. The second quantitative milestone 

must be achieved 3 years after the first milestone or 7 1/2 years 

after the nonattainment redesignation. Therefore, the second 

milestone will fall at least a year and a half after the 

attainment deadline if a maximum of 6 years is needed to attain 

the PM-10 standard. The second quantitative milestone should 

provide for continued emission.reduction progress toward 

attainment and should provide- for continued maintenance of the 

standard after the attainment date for the area. 

Subsequent milestones must be submitted at 3-year intervals 

if an area is not redesignated to attainment. Thus, if an area 

is not redesignated to attainment by the due date for when the 

second milestone must actually be achieved, a third milestone 

must be submitted. The third milestone should be submitted at 

the same time that the State is required to submit a 

demonstration that the second milestone has been met, which is 90 

days after the milestone is due, as explained in section IX 

below. This pattern of submitting subsequent milestones along 

with the demonstration for the previous milestone should be 

continued even if the moderate nonattainment area is reclassified 

as serious. Submittal of milestones must continue until the area 

is redesignated to attainment. 

VIII. Reasonable further proqress 

In addition to addressing quantitative emission reduction 

milestones, PM-10 nonattainment plans are also required to 

demonstrate reasonable further progress.24 Reasonable further 

progress is defined as "such annual incremental reductions in 

emissions of the relevant air pollutant as are required by [part 

Dl title I of the Act] or may reasonably be required by the 

Administrator for the purpose of ensuring attainment of the 

[NAAQS] by the applicable date. u25 

The SIP'S for PM-10 nonattainment areas should include 

detailed schedules for compliance with applicable control 

requirements in the areas and accurately indicate the corresponding annual emission reductions to be realized. In reviewing 

SIP revisions, EPA will determine whether the annual incremental 

emission reductions to be achieved are reasonable in light of the 

statutory objective to ensure timely attainment of the PM-10 

NAAQS. Additionally, EPA believes that it may be appropriate for 

24See sections 172 (a) (2) and 189 (c) (1) of the Act. 

25~ee section 171(1) of the Act. 
States to require early implementation of control measures that 

are not capital intensive (e.g., controlling fugitive dust 

emissions at a stationary source) while phasing in control 

measures that require significant investment, such as the 

installation of new hardware. 

The EPA will generally assess whether an area has achieved 

reasonable further progress in conjunction with determining its 

compliance with the quantitative emission reduction milestone 

requirement. Thus, as indicated below, when a State demonstrates 

an area's compliance with a quantitative milestone, it should 

also address whether reasonable further progress has been 

achieved during each of the relevant 3 years. The EPA is 

currently developing further guidance on reasonable further 

progress which will be forwarded to the States and Regional 

Offices at a later date. 

IX. Milestone and reasonable further prosress reportinq 

Within 90 days of the date on which a milestone applicable 

to an area occurs, each State in which all or part of such area 

is located must demonstrate the following to EPA: (1) All 

measures in the plan approved under section 189 of the Act have 

been implemented, and (2) the milestone has been met. The 

demonstration must be submitted in such form and manner and must 

contain such information and analyses as EPA requires [see 

section 189(c) (2) of the Act]. Thus, EPA is granted broad 

discretion in determining the manner of the submittal and the 

information contained therein. 

In order to demonstrate,that an area has met a quantitative 

milestone, the State must generally submit a report which 

demonstrates that the area has implemented RACM/RAcT and has 

achieved the emission reductions predicted in the quantitative 

milestone for the area.26 More specifically, the State should 

provide the information outlined below. 

A. RACM implementation 

The report should identify the PM-10 sources that are 

located in the area. The RACM requirements adopted by the State 

to control sources of PM-10 should be identified, and the report 

should specify the steps that have been taken to implement each 

control measure, the percent of implementation that has been 

achieved, and an estimate of the reductions achieved. The State 

should describe how the estimate of the emission reductions was 

made. 

26~ee sections 172 (c) (1) and 189 (a) (1) (C) of the Act. 
A table may be used to summarize the source(s)/source 

category(ies1 and associated control measures. This table should 

include an estimate of PM-10 emissions before and after controls. 

The report should provide an explanation of why 100 percent 

implementation was not achieved and why the projected emission 

reductions were not achieved. The State should also identify the 

steps that will be taken to achieve the emission reductions which 

were not met. The emission reductions should also be analyzed by 

year, and the report should assess whether reasonable further 

progress was achieved in each of the 3 years during the 

applicable milestone period. 

The EPA is not requiring the State to provide an updated 

emissions inventory to address the previous information. The EPA 

is requesting that the State provide sisnificant and reliable 

estimates of the percentage of the control strategy that has been 

implemented in the nonattainment area and resulting emission 

reduction progress. 

Example: The two significant PM-10 sources in a 

nonattainment area consist of reentrained road dust from 10 miles 

of unpaved roads and the change out of 50 uncertified wood 

stoves. The RACM for the area is the paving of all 10 miles of 

road and the change out of all 50 wood stoves. The State 

estimates that a total of 1000 tons per year of emission 

reductions would be achieved from the paving of all 10 miles of 

unpaved roadways and 1000 tons per year from the change out of 

the wood stoves. The State also projects that 100 tons per year 

of emission reductions would be achieved from the paving of each 

mile of roadway and 20 tons per year from the change out of each 

wood stove. In the quantitative milestone report, the State 

indicates that, due to unforeseeable economic difficulties, it 

was only able to pave a total of 5 miles of roadway and change 

out of only 25 wood stoves. The State should report the 

estimated emission reductions achieved as a result of paving 5 

miles of roadway and the change out of the 25 wood stoves. The 

State should project when it expects to complete the paving of 

the remaining 5 miles of roadway and the change out of the 

remaining 25 wood stoves. The State should also address the 

annual emission reductions that were expected and in fact 

achieved. 
ESTIMATED EMISSION REDUCTIONS TABLE 

The State should explain why the projected emission 

reductions from point sources, reentrained road dust, and 

residential wood combustion were not achieved. The State should 

also indicate its plans to achieve 100 percent implementation of 

the control measures and the associated emission reductions. If 

additional control measures are needed to obtain the reductions, 

these measures should be identified and a schedule for 

implementation provided. 

B. Enforcement and compliance measures 

Estimated 

Emission 

Reductions 

Achieved 

600 

5 0 0 

5 0 0 

500 

2 10 0 

The quantitative emission reduction milestone report should 

identify when the affected sources in the nonattainment area were 

expected to come into compliance with RACM and which sources are 

not in compliance. The report should also indicate the percent 

of compliance being achieved for appropriate source categories 

(e.g., 50 percent compliance with the voluntary wood stove 

curtailment program). The report should state whether the 

applicable recordkeeping requirements are being met, and by what 

governmental entity(ies). An indication of whether any 

compliance tests have been conducted and the results of those 

tests should also be given. Compliance information is necessary 

to adequately assess the effectiveness of the control measures 

and the associated emission reductions likely achieved. 

Percent 

Implementation 

Achieved 

66 

5 0 

50 

100 

66.5 

Source Category 

Point sources 

Reentrained road 

dust from paved and 

unpaved roadways 

Residential wood 

combustion 

Mobile sources 

Total 

C. Failure to submit a report or to meet a milestone 

If a State fails to submit a required quantitative milestone 

report for an affected PM-10 nonattainment area, or if EPA 

determines that such area has not met an applicable milestone, 

the State must submit a plan revision within 9 months after such 

failure or determination. The plan revision must assure that the 

Projected Emission 

Reductions Needed to 

Show Attainment After 

Implementation of RACM/RACT 

900 

1000 

1000 

500 

3400 
State will achieve the next milestone for the area by the 

applicable date, or attain the PM-10 NAAQS, if there is no next 

milestone. 27 

Therefore, if the projected quantitative milestone for an 

area was not achieved (i.e., the control measures were not 

implemented to the extent expected by the milestone due date), 

the report should indicate how the State plans to meet the next 

milestone or attainment date. The report should address the 

expected contents of the required plan revision, including the 

control measures that will likely be included and the emission 

reductions projected from the implementation of these additional 

measures. This plan revision must be submitted by the governor 

or his designee and must be adopted in accordance with the 

procedures required for all SIP revisions. 

If the State fails to submit the plan revision within 9 

months after EPA1s determination that the milestone was not met 

or that the State failed to submit the milestone report, EPA will 

issue a finding of failure to submit and initiate the sanctions 

process for the area.'" 

Requests for Redesisnation to Attainment 

A State that has a PM-10 nonattainment area that has been 

determined by EPA to have attained the PM-10 NAAQS, may request 

redesignation to attainment. The Administrator may grant a 

request to redesignate an area to attainment if the following 

conditions are satisfied: 

1. The EPA determines that the area has attained the NAAQS. 

2. The applicable implementation plan for the area has been 

fully approved by EPA under section 110 (k) . 

3. The EPA determines that the improvement in air quality 

is due to permanent and enforceable reductions in emissions. 

4. The State has met all requirements applicable to the L 

area under section 110 and part Dl title I, of the Act. 

5. The EPA has fully approved a maintenance plan, including 

a contingency plan, for the area as meeting the requirements of 

section 175A of the Act [see generally section 107 (d) (3) {E) of 

the Act]. 

- - 

27~ee section 189(c) (3) of the Act. 

28~ee sections 110(m) and 179(a) of the Act and 59 FR 39832, 

August 4, 1994. 
Each of these criteria is discussed in more detail in a 

memorandum from John Calcagni to the Regional Air Directors, 

dated September 4, 1992, ad&ressing the guidelines for qualifying 

for redesignation to attainment. [See "Procedures for Processing 

Requests to Redesignate Areas to Attainment" memorandum to 

Regional Air Directors from John Calcagni, Director of the Air 

Quality Management Division, September 4, 1992.1 The second half 

of the memorandum gives particular attention to the maintenance 

plan requirement under section 175A since this constitutes a new 

requirement under the 1990 Amendments. The memorandum provides 

that special concerns for areas seeking redesignation will be 

addressed on a case-by-case basis. 

If there are any questions concerning this policy, please 

contact Larry Wallace of the Integrated Policy and Strategies 

Group at (919) 541-0906. 

cc: Tom Helms, AQSSD 

Joe Paisie, AQSSD 

Rich Osias, OGC 

AQSSD:IPSG:LWallace:pfinch:MD-15:541-5628:11-3-94 

Wallace ~A/FINAL.ADP 

Concurred with Vickie Patton and Mike Prosper, OGC