MEMORANDUM 

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

RESEARCH TRIANGLE PARK, NC 27711 

MAY 2 0 2005 OFFICE OF 

AIR QUALITY PLANNING 

AND STANDARDS 

SUBJECT: Maintenance Plan Guidance Document for Certain 8-hour Ozone Areas Under 

Section 11 0( a)(1) of Clean Air Act 

FROM: LydiaN. Wegman, Director 

Air Quality Strategies and Standar s Division 

TO: Air Division Directors, Regions I-X 

. SUMMARY 

The attached document provides guidance for States in preparing maintenance plans 

under section 110(a)(l) of the Clean Air Act (CAA) for areas required to do so under 40 CFR 

51.905( c) and (d). There are approximately 87 full or partial counties that are affected, listed in 

Table 2 of the attached document. 

BACKGROUND 

On April 30, 2004 (69 FR 23858), the Environmental Protection Agency (EPA) 

designated and classified areas for the 8-hour ground-level ozone National Ambient Air Quality 

Standard (NAAQS). For most areas, these designations became effective June 15, 2004. Also 

on April30, 2004, (69 FR 23951), EPA published the final phase 1 rule for implementation of 

the 8-hour ozone NAAQS. Section 51.905( c) and (d), established in that rulemaking, set forth 

requirements for anti-backsliding purposes for areas designated attainment for the 8-hour 

standard. These provisions require these areas to submit a 10-year maintenance plan under 

section 110(a)(1) of the CAA if they also were a nonattainment area, or an attainment/ 

unclassifiable area with a section 175A maintenance plan, under the 1-hour ozone standard. 

The purpose of this guidance is to address the maintenance requirements in Section 

110(a)(1) of the CAA for these areas. 

We appreciate Region IV's leadership and the participation of other Regional Offices in 

the development of this guidance.. In addition, State and local air agencies have reviewed and 

commented on a prior draft. 

Internet Address (URL) • http://www.epa.gov 

Recycled/Recyclable • Printed with Vegetable Oil Based Inks on Recycled Paper (Minimum 25% Post consumer) 
2 

Please make this guidance available to the affected State and local air pollution control . . . agencies In your region. 

Questions on this guidance may be directed to: John Silvasi(silvasi.john@epa.gov), 

(919) 541-5666, Sharon Reinders (reinders.sharon@epa.gov), (919) 541-5284, or Annie 

Nikbakht (nikbakht.annie@epa.gov), (919) 541-5246. 

cc: OPSG 
Maintenance Plan Guidance Document for Certain 

8-hour Ozone Areas Under Section llO(a)(l) of 

Clean Air Act 

U.S. Environmental Protection Agency 

Office of Air Quality Planning and Standards 

Research Triangle Park NC 27711 

May 20,2005 
General Applicability 

1. What is the purpose of this guidance? 

Response: In a Federal Register (FR) notice published April 30, 2004 (69 FR 23858), the 

Environmental Protection Agency (EPA) designated and classified areas for the 8-hour 

ground-level ozone national ambient air quality standard (NAAQS). For most areas these 

designations became effective June 15, 2004. 1 The purpose of this guidance is to address the 

maintenance requirements in Section 110(a)(1) of the Clean Air Act (CAA) for certain areas 

designated unclassifiable/attainment for the 8-hour ozone NAAQS. Specifically, the purpose of 

this document is to give the States guidance in developing a maintenance plan for those areas that 

are designated as unclassifiable/attainment for the 8-hour ozone standard and that had a 

designation of either attainment with an approved maintenance plan or nonattainment for the 

1-hour ozone standard, as of the effective date of the area's 8-hour ozone standard designation. 

2. What is a 110(a)(1) maintenance plan? 

Response: A 110(a)(1) maintenance plan is a plan required under Section 110(a)(1) of the CAA. 

This section of the Act requires that each state adopt and submit to EPA within three years after 

the promulgation of a NAAQS (un~er section 1 09) for any air pollutant, a plan which provides 

for implementation, maintenance, and enforcement of such primary standard for all areas within 

the state. The maintenance plan must be submitted to EPA as a state implementation plan (SIP) 

revision. 

3. Does this guidance create new requirements for 8-hour ozone maintenance plans? 

Response: No. EPA's Phase 1 Implementation Rule established the requirement that certain 

areas designated unclassifiable/attainment for the 8-hour ozone NAAQS are required to submit a 

maintenance plan for the 8-hour ozone NAAQS. See 69 FR 23951 (April 30, 2004). This 

guidance is consistent with the requirements established in 110(a)(1) of the CAA and the 

provisions of EPA's Phase 1 Implementation Rule (40 Code ofFederal Regulation (CFR) 

Section 51.905(a) (3) and (4)). This guidance is designed to provide information regarding how 

States might fulfill the maintenance plan obligation established by the CAA and EPA's Phase 1 

Implementation Rule. This document does not substitute for the CAA or EPA's regulations, nor 

is it a regulation itself. Thus, it does not impose binding, enforceable requirements on any party. 

EPA retains the discretion to approve SIPs on a case-by-case basis that may differ from this 

guidance, but still comply with the statute and regulations. This guidance is a living document 

and may be revised periodically without public notice. 

4. What are the different designation scenarios associated with 8-hour ozone and 1-hour 

1 Early Action Compact (EAC) areas will have a later effective date of designation. If any such areas are initially designated 

unclassifiable/attainment for the 8-hour NAAQS and are attainment with a maintenance plan areas for the 1-hour NAAQS, they will be required 

to submit a section llO(a)(l) maintenance plan no later than 3 years after the effective date of the area's 8-hour attainment designation. 

1 
ozone area designations? 

Response: As of the effective date of the 8-hour ozone designations, there are six different 

scenarios possible with respect to the two NAAQS and their designation status: 

A. Areas that are designated unclassifiable/attainment for the 8-hour ozone NAAQS and are 

designated unclassifiable/attainment for the 1-hour ozone NAAQS (8UA/1 UA) 

B. Areas that are designated unclassifiable/attainment for the 8-hour ozone NAAQS and are 

designated nonattainment for the 1-hour ozone NAAQS. (8UA/1N) 

C. Areas that are designated unclassifiable/attainment for the 8-hour ozone NAAQS and are 

designated attainment for the 1-hour ozone NAAQS with an approved maintenance plan. 

(8UA/1M) 

D. Areas that are designated nonattainment for the 8-hour ozone NAAQS and are designated 

unclassifiable/attainment for the 1-hour ozone NAAQS. (8N/1 UA) 

E. Areas that are designated nop.attainment for the 8-hour ozone NAAQS and are designated 

nonattainment for the 1-hour ozone NAAQS. (8N/1N) 

F. Areas that are designated nonattainment for the 8-hour ozone NAAQS and are designated 

attainment for the 1-hour ozone NAAQS with an approved maintenance plan. (8N/1M) 

Table 1 summarizes the 6 scenarios. 

Table 1 - Designation Status of 8-hour Ozone Areas 

1-hour ozone 

U nclassifiab le/ N onattainment Attainment with a 

Attainment maintenance plan 

8-hour Unclassifiable/ Scenario A Scenario B Scenario C 

ozone Attainment (8UA/1UA) (8UA/1N) (8UA/1M) 

N onattainment Scenario D Scenario E Scenario F 

(8N/1UA) (8N/1N) (8N/1M) 

2 
5. Which designation scenarios are addressed in this guidance? 

Response: This guidance only addresses areas that fall under scenarios B and C from Table 1: 

areas that are designated as unclassifiable/attainment for the 8-hour ozone standard and are either 

nonattainment for the 1-hour standard (scenario B) or are designated attainment with a 175A 

maintenance plan for the '1-hour ozone standard (scenario C). Table 2 lists the specific scenario 

B and C areas that are subject to this guidance. 

Timine 

6. When must a 110(a)(l) maintenance plan for scenario Band C be submitted to EPA? 

Response: Under 40 CFR 51.905(a)(3) and (4), States must submit section 110(a)(l) 

maintenance plans no later than 3 years ":fter the effective date of the area's 8-hour ozone 

NAAQS designation. For most areas, June 15, 2004, is the effective date of the 8-hour ozone 

NAAQS designations. Thus, for these areas, the section 110(a)(1) 8-hour ozone maintenance 

plan must be submitted no later than June 15, 2007. 

If the State wishes to revise its existing 1-hour ozone SIP for a scenario B or C area, prior to 3 

years after designation, the revision would have to meet sections 11 0(1) and 193 of the Act. The 

EPA strongly recommends that the revision be incorporated into a 110(a)(1) maintenance plan 

that is submitted as part of that revision. Also note that 40 CFR 51.905(e)(1) requires approval 

of a section 110(a)(1) plan ifthe State wishes to make either ofthe following SIP revisions: (a) 

removing the obligation to submit a maintenance plan for the 1-hour NAAQS 8 years after 

approval of the initial1-hour maintenance plan; or (b) removing the obligation to implement 

contingency measures upon a violation of the 1-hour NAAQS. Please note that scenario C areas 

that are subject to 175A maintenance plan requirements are still subject to those requirements for 

as long as those requirements remain a part of the approved SIP. 

Maintenance Plan Components 

7. What are the components of a 110(a)(1) maintenance plan for scenario Band C areas? 

Response: The 8-hour ozone 110(a)(1) maintenance plan constitutes a SIP revision and must 

provide for continued maintenance of the 8-hour ozone NAAQS in the area for 10 years from the 

effective date of the area's designation as unclassifiable/attainment for the 8-hour ozone 

NAAQS. At a minimum, the maintenance plan for scenario Band C areas must include the five 

following components2

: 

2 A projection of emissions and demonstration of maintenance for 10 years is not required for any affected area if there are 

essentially no anthropogenic emissions in the nonattainment area. It would be absurd to have a maintenance plan with contingency measures for 

such an area. In addition, such an area would obviously not result in contributions to downwind nonattainment areas. 

3 
Attainment Inventory - The attainment inventory should be based on actual "typical summer 

day'' emissions of volatile organic compounds and nitrogen oxides. The Phase 1 Implementation 

Rule provides that the 1 0-year maintenance period begins as of the effective date of designation 

for the 8-hour NAAQS for the area. For purposes of an attainment emissions inventory, the State 

· may use one of any of the three years on which the 8-hour attainment designation was based (i.e., 

2001, 2002, and 2003).3 Because areas are already required to develop an inventory for 2002 

under EPA's Consolidated Emissions Reporting Rule (CERR) (40 CFR Part 51, Subpart A, 67 

FR 39602, June 10, 2002), we recommend that areas use that year as the attainment emission 

inventory base year for the section llO(a)(l) maintenance plan. 

Maintenance Demonstration - The key element of a maintenance plan is a demonstration of 

how the area will remain in compliance with the 8-hour ozone standard for the 10 year period 

following the effective date of designation as unclassifiable/attainment. The end projection year 

is 10 years from the effective date of the attainment designation. For areas with an effective date 

of designation for the 8-hour NAAQS of June 15, 2004, the end projection year may be beyond 

2014. However, the maintenance plan must project attainment for 2014. 

The typical method that areas have used in the past to demonstrate that an area will maintain the 

1-hour standard has been to identify the level of ozone precursor emissions in the area which is 

sufficient to attain the NAAQS and to show that future emissions of ozone precursors will not 

exceed the attainment levels. To perform this analysis, for the 8-hour maintenance plan the state 

needs to develop emission inventories for one of the three years used to establish the area's 

attainment status and for the projection year. 

Maintenance may also be demonstrated using other methods, such as modeling. A State should 

work with the EPA Regional Office to determine whether a specific method for demonstrating 

maintenance is appropriate. 

Ambient Air Quality Monitoring - This guidance provides general guidelines for network 

modification in the context of section llO(a)(l) maintenance areas that need to be applied in light 

of exisitng circumstances. Neither States nor EPA should treat these guidelines in ways that 

create disincentives to monitoring. 

The State should continue to operate air quality monitors in accordance with 40 CFR 58 to verify 

maintenance of the 8-hour ozone standard in the area. Any modification to the ambient air 

monitoring network, such as removal of duplicative or unnecessary monitors, should be 

accomplished through close consultation with the EPA Regional office. 

Proposed network modifications should be accompanied by technical and statistical analysis 

sufficient to document a given monitor may be removed because it is unnecessary or duplicative 

3 

Because EAC areas will have a later effective date of designation, a later year (e.g. 2005, 2006 or 2007) would be used for the 

purposes of an emissions inventory. · 

4 
in the case of network reductions or to justify the value of investing in monitoring network 

enhancements. For purposes of this guidance, duplicative means monitoring for the same 

purpose and objective. A monitor may be unnecessary when it monitored a violation of the 8-

hour standard prior to the latest five complete three-year periods but has monitored attainment 

for the latest five complete three-year periods. 4

•

5 If the monitor is violating for this period, we 

recommend that the monitoring site be retained. This time period is necessary to confirm that 

several non-overlapping data periods6 show sustained clean air due to strategic emission 

reductions rather than favorable meteorology. 

In accordance with 40 CFR 58, the final network design will be subject to the approval of the 

Regional Administrator. 

Contingency Plan - The State must develop a contingency plan that, at a minimum, will ensure 

that any violation of the 8-hour ozone NAAQS is promptly corrected. More details regarding the 

contingency plan are provided in question 11 below. Additional information on contingency 

measures can also be obtained from the EPA Office of Air Quality Planning and Standards 

(OAQPS) and the EPA policy Procedures for Processing Requests to Redesignate Areas to 

Attainment (September 4, 1992 John Calcagni memo to Air Directors) located at 

http://www .epa. gov/ttncaaal /t5/meta/m845 .html . 

Verification of Continued Attainment - The submittal should indicate how the state will track 

the progress of the maintenance plan. This is necessary due to the fact that emissions projections 

made for the maintenance demonstration depend on assumptions of point, area and mobile source 

growth. One option for tracking the progress of the maintenance demonstration, provided here as 

an example, would be for the State to periodically update the emissions inventory. The 

maintenance demonstration should project maintenance during the 10-year period following the 

date of designation for the 8-hour NAAQS, not simply that the area will be in attainment in the 

lOth year. 

States should develop interim emission projection years to show a trend analysis for maintenance 

of the standard. These emission projections can also be used as triggers for implementing 

contingency measures. We recognize that it would be difficult and time-consuming to develop 

projections for each year of the 10-year period. Therefore, the number of interim projection years 

should reflect whatever information exists regarding the potential for increases in emissions in 

the intervening years. For instance, if there is a high probability that emissions will decrease 

over the 10-year period, fewer interim projections are needed; if it is likely that emissions will 

increase to such an extent as to jeopardize continued maintenance of the standard- even 

4

(i) years 1, 2, and 3; (ii) years 2, 3 and 4; (iii) years 3, 4 and 5; (iv) years 4, 5, and 6; and (v) years 5, 6, and 7). 

5 Of course, the period 2001-2003 would necessarily have to show attainment attainment, since this guidance applies only to areas 

initially designated attainment for the 8-hour ozone NAAQS using 2001-2003 data. 

6

E.g., period (i) does not have individual years in common with either period (iv) or(v). 

5 
temporarily- over the intervening years, the number of interim projection periods should be 

sufficient to document that such increases will not interfere with maintenance of the 8-hour 

ozone standard. 

If the precursor emissions projections are higher than the baseline inventory, a demonstration 

using a methodology selected in consultation with the appropriate EPA Regional office would be 

needed to show that the increase in emissions continues to achieve compliance with the 8-hour 

ozone NAAQS. 

Where the demonstration is based on modeling, an option for tracking progress would be for the 

State to periodically (typically every three years) reevaluate the modeling assumptions and input 

data. In any event, the State should monitor the indicators for triggering contingency measures 

(as discussed in questions 10 and 11). 

Conformity 

8. Are scenario Band C areas considered "maintenance areas" for purposes of conformity 

for the 8-hour standard? 

Response: No. Conformity for the 8-hour ozone standard does not apply in 8-hour 

unclassifiable/attainment areas that are subject to the CAA 110(a)(1) maintenance plan 

requirements. Conformity applies only to areas that are nonattainment or were nonattainment 

and were then redesignated to attainment subject to the requirement to develop a maintenance 

plan under 175A of the Act with respect to a particular NAAQS. See CAA section176(c)(5) for 

conformity applicability requirements; see 40 CFR 93.101 and 93.102 for the definition of 

"maintenance area" and the applicability regulations for transportation conformity, respectively. 

Since scenario B and C areas were never designated nonattainment for the 8-hour standard and 

are not obligated to develop a maintenance plan under 175A for that standard, they are not 

subject to the conformity requirements for the 8-hour standard. Conformity for the 1-hour ozone 

standard will continue to apply in existing 1-hour nonattainment and maintenance areas 

(including scenario B and C areas) until that standard is revoked. When the 1-hour standard is 

revoked, conformity will not apply for either ozone standard in scenario B and C areas .. See 40 

CFR 51.905( e )(3). 

Second 10-Year Plan Not Required 

9. Are scenario Band C areas required to develop a second 10 year maintenance plan that 

will apply after the first 10 years? 

Response: No. The Phase 1 Implementation Rule only requires a maintenance plan for the first 

10 years following designation for the 8-hour standard; it does not require areas to adopt a second 

10-year maintenance plan as is required for areas subject to the section 175A maintenance plan 

6 
requirement. However, contingency plans approved as part of the 110(a)(1) maintenance plan 

remain in effect and contingency measures could still be triggered if the area violates the 8-hour 

standard after the initial 1 0-year period. 

Contin2ency M·easures 

10. Do 1-hour controls remain in place for 8-hour unclassifiable/attainment areas? 

Response: All control measures approved into the SIP remain in effect unless and until EPA 

approves a SIP revision removing or modifying such measures. For control measures identified 

as "applicable requirements" in section 51.900(f) of the regulations, the State may not remove a 

measure from the SIP, but can request modification of the SIP such that the area is no longer 

required to implement the measure and that it instead be a contingency measure that would be 

triggered by a future violation of the 8-hour NAAQS. Any SIP revision requesting removal or 

modification of a control measure in the approved SIP must include a demonstration (as required 

by section 110(1) and 193 of the Act) that such removal or modification will not interfere with 

maintenance of the 8-hour standard or any other applicable requirement of the Act. The Phase 1 

Rule provides that before EPA will approve a revision to a SIP removing the obligation to 

implement a contingency measure upon a violation of the 1-hour standard in scenario B and C 

areas, the state must first submit the section 110(a)(1) maintenance plan for the 8-hour NAAQS. 

See 40 CPR 51.905 (e)(l). 

See the 11 0(1) guidance document and 40 CPR 51.905( c) for more details on requirements for 

modifying or removing 1-hour controls in 8-hour unclassifiable/attainment areas. 

11. What is an 8-hour ozone 110(a)(l) contingency plan? 

Response: The Phase 1 Rule requires the section 110(a)(l) maintenance plan for scenario Band 

C areas to include contingency provisions, as necessary, to promptly correct any violation of the 

NAAQS that occurs (51.905(a)(3)(iii) and (4) (ii)). The contingency plan should ensure that the 

contingency measures are adopted expeditiously once they are triggered. Consistent with the 

manner in which EPA 4as interpreted the analogous requirements for contingency measures in 

section 175A, EPA believes that the SIP should contain an enforceable commitment to adopt and 

implement the contingency measures in a timely fashion once they are triggered. To do so, the 

plan should clearly identify the measures to be adopted and a schedule and procedure for 

adoption and implementation, and a specific time limit for action by the State. The schedule for 

adoption and implementation should be as expeditious as practicable, but no longer than 24 

months. The State should also identify specific indicators, or triggers, which will be used to 

determine when the contingency measures need to be adopted and implemented. 

The trigger for implementation of contingency measures should, at a minimum, be upon a 

monitored violation of 8-hour ozone NAAQS. Another recommended trigger is when the area 

exceeds the precursor emission levels upon which maintenance is based. Because the State may 

7 
need to adopt as well as implement the contingency measures and such action could take some 

time, we recommend that the State consider a trigger that would occur prior to a violation of the 

NAAQS. Early triggers could avoid violations of the NAAQS, thus ensuring citizens are not 

exposed to unhealthy levels of air pollution and also eliminating the potential for redesignation to 

nonattainment based upon a violation of the NAAQS. 

8 
Table 2 

1-hour Ozone Nonattainment/Maintenance Counties where at least a portion of the county was designated unclassifiable/attainment for 

the 8-hour standard as of June 15, 2004. 

Listed by Region, State, Areas and County 

With Classification, Nonattainment/Maintenance Status, P=Part, Part County Description, Rural Transport (RT) 

8- Hour Ozone U nclassifiable/ Attainment Areas 1-hour Designation Data 

Region/State 8-hour Attainment Area 8-hour Attainment Area Counties/Cities/Towns 1-Hour Area Designation 

Status 

Region 1 

NEW NH Hillsborough Co P Mont Vernon Town, Wilton Town Boston-Lawrence-Wor Serious 

HAMPHSIRE cester (E. MA), Nonattainment I 

MA-NH 

NH Hillsborough Co P Includes only the following cities and towns: Antrim Manchester, NH Marginal 

Town, Bennington Town, Deering Town, Francestown Nonattainment 

Town, Greenfield Town, Greenville Town, Hancock 

Town, Hillsborough Town, Lyndeborough Town, Mason 

Town, New Boston Town, New Ipswich Town, 

Peterborough Town, Sharon Town, Temple Town, 

Weare Town, Windsor Town 

NH Merrimack Co P The entire county except the following town: Hooksett 

NH Rockingham Co P Includes only the following cities and towns: Deerfield 

Town, Northwood Town, Nottingham Town 

NH Strafford Co P The entire county except the following cities and towns: Portsmouth-Dover-Roc Serious 

Dover, Durham, Rochester, Rollinsford, and hester, NH N onattainment 

Somersworth 

9 
8- Hour Ozone Unclassifiable/Attainment Areas 1-hour Designation Data 

Region/State 8-hour Attainment Area 8-hour Attainment Area Counties/Cities/Towns 1-Hour Area Designation 

Status 

Cheshire Co, NH NH Cheshire Co NH Cheshire Co Incomplete Data 

Incomplete Data N onattainment 

N onattainment 

MAINE ME Hancock Co P Entire county excluding the following cities and towns: Hancock & Waldo Cos, Marginal 

Bar Harbor, Blue Hill, Brooklin, Brooksville, Cranberry ME Maintenance 

Isles, Deer Isle, Frenchboro, Gouldsboro, Hancock, 

Lamoine, Mount Desert, Sedgwick, Sorrento, Southwest 

Harbor, Stonington, Sullivan, Surry, Swans Island, 

Tremont, Trenton, and Winter Harbor 

ME Waldo CoP Entire county excluding the following town):Islesboro 

ME Knox CoP Entire county excluding the following cities and towns: Knox & Lincoln Co.s, Moderate 

Camden, Criehaven, Cushing, Friendship, Isle au Haut, ME N onattainment 

Matinicus Isle, Muscle Ridge Shoals, North Haven, Owls 

Head, Rockland, Rockport, St. George, South 

Thomaston, Thomaston, Vinalhaven, and Warren 

ME Lincoln Co P Entire county excluding the following cities and towns: 

Alna, Boothbay, Boothbay Harbor, Breman, Bristol, 

Damariscotta, Dresden, Edgecomb, Monhegan, 

Newcastle, Nobleboro, South Bristol, Southport, 

Waldoboro, Westport, and Wiscasset 

ME Androscoggin Co P Entire county excluding the following town: Durham Lewiston-Auburn, ME Moderate 

N onattainment ~ - ~ ~- - --

10 
8- Hour Ozone Unclassifiable/ Attainment Areas 1-hour Designation Data 

Region/State 8-hour Attainment Area 8-hour Attainment Area Counties/Cities/Towns 1-Hour Area Designation 

Status 

ME Cumberland Co P Entire county excluding the following cities and towns: Portland, ME Moderate 

Brunswick, Cape Elizabeth, Casco, Cumberland, N onattainment 

Falmouth, Freeport, Frye Island, Gorham, Gray, 

Harpswell, Long Island, New Gloucester, North 

Yarmouth, Portland, Pownal, Raymond, Scarborough, 

South Portland, Standish, Westbrook, Windham, and 

Yarmouth 

ME York CoP Entire county excluding the following cities and towns: 

Alfred, Arundel, Berwick, Biddeford, Buxton, Dayton, 

Elliot, Hollis, Kennebunk, Kennebunkport, Kittery, 

Limington, Lyman, North Berwick, Ogunquit, Old 

Orchard Beach, Saco, Sanford, South Berwick, Wells, 

and York 

Region 3 

PENNSYLVANIA P A Somerset Co P A Somerset Co Johnstown, P A Marginal 

N onattainment 

P A Columbia Co P A Columbia Co Scranton-Wilkes-Barre, Marginal 

PA N onattainment 

P A Crawford Co P A Crawford Co Crawford Co, P A Incomplete Data 

N onattainment 

P A Juniata Co P A Juniata Co Juniata Co, P A Incomplete Data 

Nonattainment 

P A Lawrence Co P A Lawrence Co Lawrence Co, PA Incomplete Data 

N onattainment 

P A Northumberland Co P A Northumberland Co Northumberland Co, Incomplete Data 

PA N onattainment 

11 
8- Hour Ozone Unclassifiable/Attainment Areas 1-hour Designation Data 

Region/State 8-hour Attainment Area 8-hour Attainment Area Counties/Cities/Towns 1-Hour Area Designation 

Status 

PAPike Co PA Pike Co Pike Co, PA Incomplete Data 

N onattainment 

P A Schuylkill Co P A Schuylkill Co Schuylkill Co, P A Incomplete Data 

N onattainment 

PA Snyder Co PA Snyder Co Snyder Co, P A Incomplete Data 

N onattainment 

P A Susquehanna Co P A Susquehanna Co Susquehanna Co, P A Incomplete Data 

N onattainment 

PA Warren Co PA Warren Co Warren Co, P A Incomplete Data 

N onattainment 

PA Wayne Co PA Wayne Co Wayne Co, PA Incomplete Data 

N onattainment 

VIRGINIA VA Smyth Co The portion of White Top Mountain above the 4,500 feet Smyth Co, VA (White Marginal RT 

elevation in Smyth county. Top Mtn) N onattainment 

WEST VIRGINIA WV Greenbrier Co WV Greenbrier Co Greenbrier Co, WV Marginal 

Maintenance 

Region 4 

FLORIDA FLDuvalCo FLDuval Co Jacksonville, FL Section 185A 

Maintenance 

12 
8- Hour Ozone Unclassifiable/Attainment Areas 1-hour Designation Data 

Region/State 8-hour Attainment Area 8-hour Attainment Area Counties/Cities/Towns 1-Hour Area Designation 

Status 

FL Broward Co FL Broward Co Miami-Fort Moderate 

Lauderdale-W. Palm Maintenance 

FL Miami-Dade Co FL Miami-Dade Co Beach, FL 

FL Palm Beach Co FL Palm Beach Co 

FL Hillsborough Co FL Hillsborough Co Tampa-St. Petersburg- Marginal 

Clearwater, FL Maintenance 

FL Pinellas Co FL Pinellas Co 

KENTUCKY KY Greenup Co P The area bounded as follows: Beginning at a point where Huntington-Ashland, Moderate 

the Ohio River meets the Greenup-Boyd County Line; WV-KY Maintenance 

proceeding southwest along the Greenup-Boyd County 

Line to the junction of the East Fork of the Little Sandy 

River and the Greenup-Boyd County Line; proceeding 

north and west along the East Fork of the Little Sandy 

River to the confluence of the Little Sandy River; 

proceeding north along the Little Sandy River to the 

confluence of the Ohio River;proceeding east along the 

Ohio River to the beginning. 

KY Fayette Co KY Fayette Co Lexington-Fayette, KY Marginal 

Maintenance 

KY Scott Co KY Scott Co 

KY Daviess Co KY Daviess Co Owensboro, KY Marginal 

13 
8- Hour Ozone Unclassifiable/Attainment Areas 1-hour Designation Data 

Region/State 8-hour Attainment Area 8-hour Attainment Area Counties/Cities/Towns 1-Hour Area Designation 

Status 

KY Hancock Co P The area bounded as follows: Beginning at the 

Intersection of U.S. 60 and the Hancock-Daviess County 

Line; proceeding east along U.S. 60 to the intersection of 

Yellow Creek and U.S. 60; proceeding north and west 

along Yell ow Creek to the confluence of the Ohio River; 

proceeding west along the Ohio River to the confluence 

of Blackford Creek; proceeding south and east along 

Blackford Creek to the beginning. 

KY Edmonson Co KY Edmonson Co Edmonson Co, KY Marginal RT 

Maintenance 

KY Livingston Co P The area bounded as follows: Beginning at the point Paducah, KY Marginal 

where the Marshall, McCracken, and Livingston County Maintenance 

Lines meet; proceeding due north to the Ohio River; 

proceeding east along the Ohio River and that part of the 

Livingston County Line to the northern most point of 

Cumberland Island and then south to the point of 

confluence of the Cumberland River; proceeding east on 

the Cumberland River to the intersection of U.S. 60 and 

the Cumberland River; proceeding north on U.S. 60 to 

the junction of Joe Grimmet Road and U.S. 60; 

proceeding to the end of Joe Grimmet Road and 

extending a line from that point to the junction of U.S. 

70 and Heater Store Road; proceeding south along 

Heater Store Road to the intersection ofKy 1889 and 

Heater Store Road; proceeding south on Harvey Road to 

the junction ofKy 453 and Harvey Road; proceeding 

west on Ky 453 to the junction of Haddox Road and Ky 

453; proceeding south along Haddox Road to the 

Tennessee River (at Haddox Ferry); proceeding west on 

the Tennessee River to the beginning --

14 
8- Hour Ozone Unclassifiable/Attainment Areas 1-hour Designation Data 

Region/State 8-hour Attainment Area 8-hour Attainment Area Counties/Cities/Towns 1-Hour Area Designation 

Status 

SOUTH SC Cherokee Co SC Cherokee Co Cherokee Co, SC Marginal 

CAROLINA Maintenance 

Region 5 

MICHIGAN MIBayCo MIBayCo Saginaw-Bay Incomplete Data 

City-Midland, MI Maintenance 

MI Midland Co MI Midland Co 

MI Saginaw Co MI Saginaw Co 

omo OH Preble Co OH Preble Co Preble Co, OH Section 185A 

Maintenance 

WISCONSIN WI Walworth Co WI Walworth Co Walworth Co, WI Marginal 

Maintenance 

Region 6 

LOIDSIANA LA Lafayette Par LA Lafayette Par Lafayette, LA Section 185A 

Maintenance 

LA Calcasieu Par LA Calcasieu Par Lake Charles, LA Marginal 

Maintenance 

LA Jefferson Par LA Jefferson Par New Orleans, LA Section 185A 

Maintenance 

LA Orleans Par LA Orleans Par 

LA St Bernard Par LA St Bernard Par 

LA St Charles Par LA St Charles Par 

LA Beauregard Par LA Beauregard Par Beauregard Par, LA Incomplete Data 

Maintenance --

15 
8- Hour Ozone U nclassifiable/ Attainment Areas 1-hour Designation Data 

Region/State 8-hour Attainment Area 8-hour Attainment Area Counties/Cities/Towns 1-Hour Area Designation 

Status 

LA Grant Par LA Grant Par Grant Par, LA Incomplete Data 

Maintenance 

LA Lafourche Par LA Lafourche Par LaFourche Par, LA Incomplete Data 

Maintenance 

LA Pointe Coupee Par LA Pointe Coupee Par Pointe Coupee Parish, Incomplete Data 

LA Maintenance 

LA StJames Par LASt James Par StJames Par, LA Incomplete Data 

Maintenance 

LA St Mary Par LA St Mary Par St Mary Par, LA Incomplete Data 

Maintenance 

NEW MEXICO NM Dona Ana Co P Dona Ana Co The area bounded by the New Sunland Park, NM (New Area 

Mexico-Texas State line on the east, the New Mexico- 1995) Marginal 

Mexico international line on the south, the Range N onattainment 

3E-Range 2E line on the west, and the N3200 latitude 

line on the north. 

TEXAS TX ElPaso Co TX El Paso Co El Paso, TX Serious 

N onattainment 

TX Victoria Co TX Victoria Co Victoria, TX Incomplete Data 

Maintenance 

Region 7 

KANSAS and KS Johnson Co KS Johnson Co Kansas City, MO-KS Other 

MISSOURI Maintenance 

KS Wyandotte Co KS Wyandotte Co 

16 
8- Hour Ozone Unclassifiable/Attainment Areas 1-hour Designation Data 

Region/State 8-hour Attainment Area 8-hour Attainment Area Counties/Cities/Towns 1-Hour Area Designation 

Status 

MO Clay Co MO Clay Co 

MO Jackson Co MO Jackson Co 

MO Platte Co MO Platte Co 

Region 8 

UTAH UTDavis Co UT Davis Co Salt Lake City, UT Moderate 

Maintenance 

UT Salt Lake Co UT Salt Lake Co 

Region 9 

ARIZONA AZ Maricopa Co P Gila River Indian tribe area Phoenix, AZ Serious 

Nonattainment 

CALIFORNIA CAKernCo P Indian Wells Valley planning area: That portion of Kern East Kern Co, CA Serious 

County contained within Hydrologic Unit #18090205. N onattainment 

(redesignated to attainment/maintenance on 06/21/04) on June 15, 2004 

CA Monterey Co CA Monterey Co Monterey Bay, CA Moderate 

Maintenance 

CA San Benito Co CA San Benito Co 

CA Santa Cruz Co CA Santa Cruz Co 

17 
8- Hour Ozone Unclassifiable/Attainment Areas 1-hour Designation Data 

Region/State 8-hour Attainment Area 8-hour Attainment Area Counties/Cities/Towns 1-Hour Area Designation 

Status 

CA San Diego Co P That portion of San Diego County that includes the areas San Diego, CA Serious 

listed below: La Posta Areas #1 and #2 Cuyapaipe Area Maintenance 

Manzanita Area Campo Areas # 1 and #2 The boundaries 

for these designated areas are based on coordinates of 

latitude and longitude derived from EPA Region 9's GIS 

database and are illustrated in a map entitled "Eastern 

San Diego County Attainment Areas for the 8-Hour 

Ozone NAAQS," dated March 9, 2004, including an 

attached set of coordinates. The map and attached set of 

coordinates are available at EPA's Region 9 Air Division 

office. The designated areas roughly approximate the 

boundaries of the reservations for these tribes, but their 

inclusion in this table is intended for CAA planning 

purposes only and is not intended to be a federal 

determination of the exact boundaries of the reservations. 

Also, the specific listing of these tribes in this table does 

not confer, deny, or withdraw Federal recognition of any 

of the tribes so listed nor any of the tribes not listed. 

CA Santa Barbara Co CA Santa Barbara Co Santa Barbara-Santa Serious 

Maria-Lompoc, CA Maintenance 

CA Sutter Co P Excluding that portion of the Sutter Buttes mountain Yuba City, CA Section 185A 

range at or above 2,000 feet in elevation. N onattainment 

CA Yuba Co CA Yuba Co 

NEVADA NV Washoe Co NV Washoe Co Reno, NV Marginal 

N onattainment 

Region 10 

18 
8- Hour Ozone Unclassifiable/Attainment Areas 1-hour Designation Data 

Region/State 8-hour Attainment Area 8-hour Attainment Area Counties/Cities/Towns 1-Hour Area Designation 

Status 

OREGON OR Marion Co P OR Marion Co P Salem, OR Incomplete Data 

N onattainment 

OR Polk CoP OR Polk CoP 

Salem Area Salem Area Transportation Study 

Transportation Study 

19 
8- Hour Ozone Unclassifiable/Attainment Areas 1-hour Designation Data 

Region/State 8-hour Attainment Area 8-hour Attainment Area Counties/Cities/Towns 1-Hour Area Designation 

Status 

WASHINGTON WAKing CoP The following boundary includes all of Pierce County, and all of King Seattle-Tacoma, W A Marginal 

County except a small portion on the northeast corner and the western Maintenance 

portion of Snohomish County: Starting at the mouth of the Nisqually 

river extend northwesterly along the Pierce County line to the 

southernmost point of the west county line of King County; thence 

northerly along the county line to the southernmost point of the west 

county line of Snohomish County; thence northerly along the county 

line to the intersection with SR 532; thence easterly along the north 

line of SR 532 to the intersection of 1-5, continuing east along the 

same road now identified as Henning Rd, to the intersection with SR 9 

at Bryant; thence continuing easterly on Bryant East Rd. and Rock 

Creek Rd., also identified as Grandview Rd., approximately 3 miles to 

the point at which it is crossed by the existing BPA electrical 

transmission line; thence southeasterly along the BP A transmission 

line approximately 8 miles to point of the crossing of the south fork of 

the Stillaguamish River; thence continuing in a south-easterly 

direction in a meander line following the bed of the River to Jordan 

Road; southerly along Jordan Road to the north city limits of Granite 

Falls; thence following the north and east city limits to 92nd St. N.E. 

and Menzel Lake Rd.; thence south-southeasterly along the Menzel 

Lake Rd. and the Lake Roesiger Rd. a distance of approximately 6 

miles to the northernmost point of Lake Roesiger; thence southerly 

along a meander line following the middle of the Lake and Roesiger 

Creek to Woods Creek; thence southerly along a meander line 

following the bed of the Creek approximately 6 miles to the point the 

Creek is crossed by the existing BPA electrical transmission line; 

thence easterly along the BP A transmission line approximately 0.2 

miles; thence southerly along the BPA Chief Joseph-Covington 

electrical transmission line approximately 3 miles to the north line of 

SR 2; thence southeasterly along SR 2 to the intersection with the east 

county line of King county; thence south along the county line to the 

northernmost point of the east county line of Pierce County; thence 

along the county line to the point of beginning at the mouth of the 

Nisqually River. 

WAPierce Co WA Pierce Co 

20 
8- Hour Ozone U nclassifiable/ Attainment Areas 1-hour Designation Data 

Region/State 8-hour Attainment Area 8-hour Attainment Area Counties/Cities/Towns 1-Hour Area Designation 

Status 

W A Snohomish Co P Snohomish Co The following boundary includes all of Pierce County, 

and all of King County except a small portion on the northeast comer 

and the western portion of Snohomish County: Starting at the mouth 

of the Nisqually river extend northwesterly along the Pierce County 

line to the southernmost point of the west county line of King County; 

thence northerly along the county line to the southernmost point of the 

west county line of Snohomish County; thence northerly along the 

county line to the intersection with SR 532; thence easterly along the 

north line of SR 532 to the intersection of 1-5, continuing east along 

the same road now identified as Henning Rd, to the intersection with 

SR 9 at Bryant; thence continuing easterly on Bryant East Rd. and 

Rock Creek Rd., also identified as Grandview Rd., approximately 3 

miles to the point at which it is crossed by the existing BPA electrical 

transmission line; thence southeasterly along the BPA transmission 

line approximately 8 miles to point of the crossing of the south fork of 

the Stillaguamish River; thence continuing in a south-easterly 

direction in a meander line following the bed of the River to Jordan I 

Road; southerly along Jordan Road to the north city limits of Granite 

Falls; thence following the north and east city limits to 92nd St. N.E. 

and Menzel Lake Rd.; thence south-southeasterly along the Menzel 

Lake Rd. and the Lake Roesiger Rd. a distance of approximately 6 

miles to the northernmost point of Lake Roesiger; thence southerly 

along a meander line following the middle of the Lake and Roesiger 

Creek to Woods Creek; thence southerly along a meander line i 

following the bed of the Creek approximately 6 miles to the point the I 

Creek is crossed by the existing BPA electrical transmission line; 

thence easterly along the BPA transmission line approximately 0.2 

miles; thence southerly along the BPA Chief Joseph-Covington 

electrical transmission line approximately 3 miles to the north line of 

SR 2; thence southeasterly along SR 2 to the intersection with the east 

county line of King county; thence south along the county line to the 

northernmost point of the east county line of Pierce County; thence 

along the county line to the point ofbeginning at the mouth of the 

Nisqually River. 

OREGON and OR Clackamas Co P OR Clackamas Co P Portland-Vancouver Marginal 

WASHINGTON AQMA,OR-WA Maintenance 

OR Multnomah Co P OR Multnomah Co P 

21 
8- Hour Ozone Unclassifiable/Attainment Areas 1-hour Designation Data i 

Region/State 8-hour Attainment Area 8-hour Attainment Area Counties/Cities/Towns 1-Hour Area Designation 

Status 

OR Washington CoP OR Washington Co P 

WAClarkCoP WA Clark CoP 

Air Quality Maintenance Air Quality Maintenance Area 

Area -- -- -- - -- -- - --

22