Hartford City
Manchester Town
Marlborough Town
Newington Town
Rocky Hill Town
Simsbury Town
South Windsor Town
Suffield Town
West Hartford Town
Wethersfield ‘Town
Windsor Town
Windsor Locks Town

Litchfield County (pt)
Barkhamsted Town

- New Hartford Town

Middlesex County (pt)
East Haddam Town

New London County (pt)
Colchester Town

Tolland County (pt)
Andover Town
Bolton Town |
Columbia Town
Coventry Town
Ellington Town
Hebron Town
Somers Town
Stafford Town
Tolland Town
Vernon Town
Willington Town

Middletown, CT PMSA:

Middlesex County (pt)
Cromwell Town
Durham Town
East Hampton Town
Haddam Town
Middlefield Town
Middletown Town

“Middletown city
Portland Town

New Britain, CT PMSA:

Hartford County (pt)
Berlin Town

, New Britain Town
New Britain City

Plainville Town

Southington Town


October 1 ~ January 31

Duluth, MN-WI MSA

Minneapolis-St. Paul, MN-WI MSA

Chico, CA MSA

Fresno, CA MSA

Modesto, CA MSA

Reno, NV MSA

Sacramento, CA MSA

San Francisco-Oakland~San Jose, CA CMSA
Stockton, CA MSA :

t - Feb
Las Vegas, NV MSA
Phoenix, AZ MSA

Septe 1_- Februa: 29

Spokane, WA MSA

14


Philadelphia-Wilmington-Trenton, PA-DE-NJ-MD_ PMSA:
Philadelphia, PA-NJ PMSA:

Bucks County, PA
Chester County, PA
Delaware County, PA
Montgomery County, PA
Norristown Borough
- Philadelphia County, PATM
Philadelphia City
Burlington County, NJ
Camden County, NJ
Camden City
Gloucester County, NJ

Trenton, NJ PMSA:

Mercer County
Trenton City

Vineland-Millville-Bridgeton, NJ PMSA:
Cumberland County
Bridgeton City
Millville city
Vineland City
Wilmington, DE-NJ-MD PMSA:
Salem County, NJ
Portland-Vancouver, OR-Wi SA
Portland, OR PMSA:
Clackamas County
Portland City (pt)
Multnomah County
Portland City (pt)
Washington County
- Portland City (pt)
Yamhill County
Vancouver, WA PMSA:

Clark County
Vancouver City

24


For each of the covered CO nonattainment areas, the five highest
days in each month were calculated and plotted for 1988 and 1989. Bar
graphs reflecting this information for the originally-proposed 39%
oxygenated gasoline areas have been placed in the dockét.

Preliminary control periods under Approach I were identified by noting
those months where any of the five highest days exceeded the National
Ambient Air Quality- Standard (NAAQS) for CO.

Examination:of the data.resulting, from the Approach I analysis
revealed considerable heterogeneity in the length and “temporal °*~ se
placement of a number of areas that share fuel distribution facilities.
As a result, it was suggested that there is a need to constrain this
heterogeneity to facilitate transportation logistics. That is, where
possible, areas that share pipeline distribution systems should be
given the same control period. In evaluating this suggestion, EPA
considered a second way of analyzing the monitoring data.

This second approach used the exceedances of the carbon monoxide
standard at the design value monitor in the design value year (the year
in which the design value was established), to identify the months the

’ individual areas were prone to high ambient concentrations of carbon
monoxide. The outer boundaries of the season in which these
exceedances at the design value monitor occurred was considered along
with the larger body of monitoring data mentioned before.
Determination of the control periods in this manner results in a
significant degree of consistency among the control periods of areas

_ which share oxygenate sources and transportation facilities.

In many cases, using both approaches, the 4~month statutory
minimum length for the control period was the controlling factor, along
with the requirement that, in general, these programs begin no later
than November 1, 1992.

The result of the second analysis, called Approach II, has been
used by the Agency as the basis for most of the control periods
established in today's guidance. Several modifications, noted below,
were made to Approach II. EPA's guidance on control periods by area is
set forth in Table 1.

* In the July 9, 1991 Federal Register Notice, this number
was 41, not 39. As of the current date, neither Steubenville, OH
nor Winnebago, WI has been designated as a CO nonattainment area.
Therefore the number of CO nonattainment areas covered by these
guidelines is currently 39. Both of these areas have been
deleted from Table 1.

5 These bar graphs appear in a document titled, "Bar graphs
of carbon monoxide in Non-Attainment Areas - Revised," June 7,
1991, which is contained in the public docket.

5


Los Angeles~Anaheim-Riverside, CA CMSA

Anaheim-Santa Ana, CA PMSA:

Orange County
Anaheim City
Santa Ana City

Los Angeles-Long Beach,CA PMSA:

Los Angeles County
Burbank City
Long Beach City
Los Angeles City
Pasadena City
Pomona City

Oxnard-Ventura, CA PMSA:

Ventura County
Oxnard City
San Buenaventura (ventura) city

Riverside-San Bernardino, CA PMSA:

Riverside County
Palm Springs City
Riverside City
San Bernardino County
San Bernadino City

Ne’ fe) > rthern New Jersey- Long Island NY-NJ-CT
Bergen-Passaic, NJ PMSA:

Bergen County
Passaic County
Paterson City

Bridgeport-Milford, CT PMSA:

Fairfield County (pt)
Bridgeport Town

Bridgeport City
Easton Town
Fairfield Town
Monroe Town
Shelton Town
Stratford. Town
Trumbull Town

‘21


Fort Collins, Loveland, CO MSA

Larimar County
Fort Collins City
Loveland City

Fresno, CA MSA

Fresno County
Fresno City

Greensboro-Winston-Salem-High Point, NC MSA

Davidson County
High Point City (pt)
Davie County
Forsyth County
Winston-Salem City
Guilford County
Greensboro City
High Point City (pt)
Randolph County
High Point City (pt)
Stokes County
Yadkin County

Ss Vegas ISA

Clark County
Las Vegas City
Medford, OR MSA

"Jackson County
Medford City

Men Ss -AR-MS_MS.

Shelby County, TN
Memphis City
Tipton County, TN

Minneapolis-St. Paul, MN-WI MSA

Anoka, County, MN
Carver County, MN
Chisago County, MN .
Dakota County, MN
Hennepin County, MN
Bloomington City
Minneapolis City
Isanti County, MN

27


New York, NY PMSA:

Bronx County

New York City (pt)
Kings County

New York City (pt)
New York County

New York City: (pt):
Putnam County
Queens County

New York City (pt)
Richmond County

New York City (pt)
Rockland County .
Westchester County

White Plains City

Newark, NJ PMSA:

Essex County
Newark City
Morris County
Sussex County
Union County
Elizabeth City

Norwalk, CT PMSA:

Fairfield County (pt)
Norwalk Town
Norwalk City
Weston Town
Westport Town
Wilton Town

Orange County, NY PMSA:
Orange County
Stamford, CT PMSA:
Fairfield county (pt)
Darien Town
Greenwich Town
New Canaan Town

Stamford Town
Stamford City

23


North Andover Town
Salisbury Town
West Newbury Town

Lowell, MA-NH PMSA:

Middlesex County, MA (pt)
Billerica Town .
Chelmsford Town
Dracut Town
Dunstable Town
Lowell city
Pepperell Town
Tewksbury Town
Tyngsborough Town
Westford Town

Salem-Gloucester, MA PMSA:

Essex County (pt)
Beverly City
Danvers Town
Essex Town
Gloucester City
Hamilton Town
Ipswich Town
Manchester Town
Marblehead Town
Middleton Town
Peabody City
Rockport Town
Rowley Town
Salem City
Swampscott Town
Topsfield Town
Wenham Town

Cleveland-Akron-Lorain, OH CMSA
Akron, OH PMSA:

Portage County
Kent City
Summit. County
Akron City
Barberton City
Cleveland, OH PMSA:

Cuyahoga County
Cleveland City

Geauga County

Lake County

18:


the winter of 1992-93 of less than four months. Nevertheless, EPA
believes that the time necessary to successfully implement. this program
this first year justifies the November 1 start date. In any case,
states will control periods commencing prior to November 1 are not
precluded from starting their programs prior to the November 1
deadline.

EPA also believes that the November 1, 1992 start date is
consistent with the Act, which provides that the oxygenated gasoline
requirement "shall take effect no later than November 1, 1992 (or at
such other date during 1992 as the Administrator establishes under the
preceding provisions of this paragraph) ."

For additional information and discussion of the issues related to
start date, the February 5, .1992 Supplemental 1 Notice should be
consulted. -- - a -

Geographic Scope
According to Section 211(m) of the Act, SIP revisions must be

submitted by each State in which there is located all or part of an
area which is designated under Title I as a nonattainment area for
carbon. monoxide-and.which has.a.carbon monoxide. design value..of..9..5..
parts per million (ppm) or above based on data for the two-year period
of 1988 and 1989’ and calculated according to the most recent
interpretation methodology issued by the Administrator prior to
enactment of the 1991 amendments to the Act. These control areas are
as follows:

1. Boston-Lawrence-Salem, MA-NH CMSA

2. Hartford-New Britain-Middletown, CT CMSA

3. New York-Northern New Jersey-Long Island, NY-NJ-CT CMSA
4. Syracuse, NY MSA

5. Baltimore, MD MSA

6. Philadelphia-Wilmington-Trenton, PA-NJ-DE-MD CMSA
7. Washington, DC-MD-VA MSA

8.. Greensboro-Winston-Salem-High Point, NC MSA

9. Memphis, TN-AR-MS MSA

10. Raleigh-Durham, NC MSA

11. Cleveland-Akron-Lorain, OH CMSA

12. Duluth, MN-WI MSA

13. Minneapolis-St. Paul, MN-WI MSA

14. Albuquerque, NM MSA

15.. El Paso, TX MSA

16. Colorado Springs, CO MSA

17.. Denver-Boulder, CO CMSA

® The Agency has determined that the 1988 and 1989 data from several areas is
inadequate to properly characterize the ambient concentrations.of CO. Therefore, for
these areas - Boston, Cleveland and Washington, D.C. - older, more representative
data has been used.

10.


Other CO Nonattainment Areas Required to Implement -Oxygenated Gasoline
P.

rograms ":

Missoula, MT
Fairbanks, AK
Grant's Pass, OR
Klamath Co., OR

2 Please see the November 6, 1991 Federal Register Notice on Air Quality
Designations (56 FR.56694 November 6, 1991) for a more detailed definition of the
boundaries for these CO nonattainment areas. This notice is scheduled to be updated
shortly.

30


the fact that all carbon monoxide exceedances from 1990 and 1991
occurred between October and April, EPA's guidance indicates a 7-month
control period for the New York City control area, for the period of
October 1 through April 30.

Based on discussions during the regulatory negotiation process,
and in accordance with the "Agreement in Principle," EPA had proposed
to modify the control periods for Grant's Pass, Medford and Klamath, in
the state of Oregon to the four months from October 1 through January
31. This was a modification of the control period originally proposed
in the July 9, 1991 Notice.’ The ambient air data from southern
Oregon indicates high ambient concentrations for these counties in the
months of December and January. The Agency considered additional
months given the four-month statutory minimum. For one county,
February had somewhat lower concentrations than October, and for the
other two counties the February and October concentrations were
approximately the same. EPA has received additional comments on this
modification in response to the February 5, 1992 supplemental notice.
The State of Oregon has requested that the control period for southern
Oregon be returned to the original November through February period.
The State believes that this control period will more accurately match
the time when these areas are prone to high ambient concentrations of
co.

Based on EPA's analysis of the data alone, these counties are not
prone to high ambient concentrations of CO in either October or
February. Nevertheless, the Act requires a minimum control period of
four months. While the statute specifies that the control period is to
constitute that time of year in which the area is. prone to high ambient
cO concentrations, this criterion is insufficient for selecting whether.
October or February should be included to meet the statutory minimum in
this case. In such a case, the Agency believes it may reasonably
consider other factors, including the state's preference, where the
environmental data does not provide a substantial basis for
distinction. The commenters were split on their choice of control
periods whether to include October of February. Therefore, the Agency
has decided to concur with the State of Oregon's request to set the
control period from November through February.

EPA has decided to adopt Approach II primarily because it is more
consistent with the methodology used to determine attainment. This is
consistent with the statute's emphasis on attainment status and design
value, beth of which are based on design monitor values. This approach
will also aid in the implementation of these state programs by helping
to integrate control periods for areas which share oxygenate sources
and transportation facilities. EPA is fully confident that Approach II
reasonably reflects the period "prone to high ambient concentrations of
carbon monoxide" for the applicable areas.

7 56 FR 51151 (July 9, 1991).


By using only data from the design value monitor in the design
value year and by looking only at non-overlapping 8-hour averages,
Approach II ties the control period determination more closely to the
methodology used to define attainment. Violation of the 8-hour
standard occurs when the second highest non-overlapping 8-hour average
in a year exceeds the NAAQS for CO. In addition, Approach II also
provides more logical consistency in the gasoline distribution network.

Using this second approach, the eastern seaboard, with the
exception of the New York City area, converges on a common core 4~month
period from November through February. This same core period prevails
in Petroleum Administration for Defense Districts (PADDs)® 3 and 4 and
in a substantial portion of PADD 5. Five areas were assigned control
periods in excess of four months using this approach.

One area which merits a separate analysis is the New York City
CMSA. Data from 1988-89 suggested that a control period extending into
the summer might be warranted in the New York City area. Based on this ~
data, EPA initially proposed a 12-month control period. However,
consideration of the area's 1990 and.1991 data supports a shorter
control period. The New York State Deputy Commissioner previously
proposed that the New York City CMSA program require 2.7% oxygen by
-weight..in gasoline from.November 1 to..March 31, and 2.0% gen by
weight from April 1 to October 31. In response to the Fel ry 5, 1991
supplemental notice, comments were received from the New York State
Department of Environmental Conservation, the New Jersey Department of
Environmental Protection and Energy, the Connecticut Department of
Environmental Protection and New York City Department of Environmental
Protection officials requesting a 7-month control period based upon the
_ 1990 and 1991 data. EPA has had extensive discussions with New York,
New Jersey and Connecticut state officials, to attempt to coordinate
their input regarding this issue for their common control area. As a
result of these discussions, the requests from the local officials, and

‘ The definition of PADD is contained in the Petroleum
Supply Monthly (DOE/EIA-0109), prepared by the Energy Information
Administration, Office of Oil and Gas, U.S. Department of Energy
(May 1991). The definition, which appears on page 143, is as

follows: _

. Petroleum Administration for Defense (PAD) Districts.
Geographic aggregations of the 50 States and the
District of Columbia into five districts by the
Petroleum Administration for Defense in 1950. These districts
were originally instituted for economic and geographic
reasons as Petroleum Administration for War (PAW)

Districts, which was established in 1942.

A map showing PADDs by State appears on page 110.of the
above referenced publication.


Medina County
Lorain-Elyria, OH PMSA:
Lorain County
Elyria City
Lorain City

Denver-Boulder co_CMSA

Boulder-Longmont, CO PMSA:

Boulder County
Boulder City
Longmont City

Denver, CO PMSA:

Adams County
Arapahoe County
Denver County
Denver City
Douglas County
Jefferson County

Hartford-New Britain-Middletown, CT CMSA

Bristol, CT PMSA:

Hartford. County (pt)
Bristol Town

Bristol City
Burlington Town

Litchfield County (pt)
Plymouth Town

Hartford, CT PMSA:

Hartford County. (pt)
Avon Town
Bloomfield Town
Canton Town
East Granby Town
East Hartford Town
East Windsor Town
Enfield Town=
Farmington Town
Glastonbury Town
Granby Town
Hartford Town

19.


Specific response to the comments concerning the accuracy and
validity of the 1986 and 1987 Boston monitoring data will be contained
in the Technical Support Document to the Title I
Designation/Classification Corrections Notice. Using the 1986 and 1987
data, EPA concludes that the Boston CMSA has a design value of 9.8 ppm
co and, hence, is required to implement an oxygenated gasoline program.

The County of Sacramento has. submitted a letter in response to the
Supplemental Notice of Proposed Guidance. The letter states that the
County would like to petition the EPA Administrator under section
211(m).(3) of the Act that the Agency alter the control period as
proposed for Sacramento from October through January to November
through February. EPA does not believe that the ambient data warrant
such a change. There were CO exceedances in Sacramento in October and
none in February during the 1989-1990 period. EPA will address. the
issues raised more fully at such time as a petition is actually
received.

A comment from the California Air Resources Board (CARB) points
out that EPA, in the proposed guidelines, stated that it will consider
recent ambient air’ quality data in issuing final guidelines or in
reviewing individual SIPs. CARB recommends that the Los Angeles
control period should not include the month of September. The reason
given is that there were no. CO exceedances in September for the years
1989 to 1991. This would result in a control period of October 1
through February 29. EPA agrees that it would be appropriate to
eliminate the month of September from Los Angeles' control period and
has adjusted Table 1 accordingly.

Effective Date

In the Notice of Proposed Guidance on Establishment of Control
Periods published on July 9, 1992 EPA proposed that gasoline programs
with control periods beginning in September, October, .and November
would have effective dates of September 1, 1992, October 1, 1992, and
November 1, 1992, respectively. In addition, EPA proposed that for
areas with a control period of twelve months, the effective date will
be September 1, 1992. Based on comments, however, EPA proposed in
the February 5, 1992 Supplemental Notice that the effective date for
all areas with control periods beginning on or before November 1, 1992
will be no later than November 1, 1992.

After considering the public comments, EPA is recommending a
November 1, 1992 start date for all programs. EPA is concerned that an
effective date prior to November 1, 1992 would afford industry and the
states insufficient time to implement the oxygenated gasoline programs.
EPA recognizes that a November 1 start date could deprive areas of air
quality benefits from the oxygenated gasoline program during that
portion of control periods prior to November 1, 1992. In addition, EPA
recognizes that certain areas may have an effective control period in

8 56 FR 31148, 31153 (July 9, 1991).

9


San Francisco-Oakland-San Jose, CA CMSA
Oakland, CA PMSA:

Alameda County
Berkeley City
Livermore City
Oakland. City

Contra Costa County
San Francisco, CA PMSA:

Marin County

San Francisco County
San Francisco City

San Mateo County

San Jose, CA PMSA:

Santa Clara County
Palo Alto City
San Jose City

Santa Cruz, CA PMSA:

Santa Cruz.County
Santa Cruz City

Santa Rosa-Petaluma, CA PMSA:

Sonoma County
Petaluma City
Santa Rosa City

Vallejo-Fairfield-Napa, CA PMSA:

Napa County
Napa City
Solano County
Fairfield city
Vallejo City

Seattle-Tacoma, WA CMSA:
Seattle, WA PMSA:
King County
Auburn City
Seattle City
Snohomish County
Everett City

25


Establishment of Control Periods under Section 211(m)
of the Clean Air Act as Amended

U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of. Mobile Sources

Field Operations and Support Division


stated above, Table 1 includes the entire CMSA or MSA, whichever is
larger.

For certain multi-state MSAs and CMSAs, the portions of one or
more of the states in the MSA or CMSA are not actually designated as
being in CO nonattainment. For example, the Memphis CMSA extends to
areas of Arkansas and Louisiana which are designated as attainment for
co. This problem arises in a number of additional states.

The Agency notes that section. 211(m) (1). obligates "{e]ach State in.
which there is located all or part of an area which is designated under
title I as a nonattainment area for carbon monoxide...(to] submit to
the administrator a State implementation plan...for such area..."
Section 211(m)(2) provides further that SIP revisions require that the
oxygenated. gasoline program apply to fuel refiners or marketers in the
larger of the CMSA or MSA in which the CO nonattainment area is
located. The Agency does not beliévé that statés containing only an
attainment portion of the MSA or CMSA are obligated to submit SIP
revisions. In the case of such states, the attainment portions of the
MSA or CMSA located within their boundaries are not themselves
designated under title I as a nonattainment area for CO. These states
ubmit SIPs for such areas. Therefore,
re implement “an Oxygenatéa ~~

qu.
gasoline program in Shelby and Tipton Counties.

The Agency does not believe that Congress intended States
containing nonattainment portions of the MSA or CMSA to establish
oxygenated gasoline programs requiring that gasoline sold or dispensed
for use outside its borders be oxygenated. An interpretation that
section 211(m) requires such states to establish oxygenated gasoline
programs applicable in this manner to the portions of the MSA or CMSA
outside their borders raises serious constitutional issues regarding
the principle of a State's sovereignty vis a vis other States and about
the constitutionality of Congress's delegation of power to regulate
interstate commerce.

For areas that have carbon monoxide design values of 9.5 parts per
million (ppm) for any two year period after 1989, the Act requires that
a revision to the SIP shall be submitted within ig months after such
two year. period. The statute does not specify.whether two-year periods
after 1989 are to be overlapping or mutually exclusive. EPA believes
the two-year period was specified to ensure that a sufficient amount of

‘data is considered, and therefore an overlapping approach is more
appropriate. EPA will address the geographic scope issues for these
areas as such action becomes necessary.

One such area is Ogden, Utah which has been classified as
nonattainment with a design value of 9.9 ppm based on 1989 and 1990
data. Ogden will be required to implement an oxygenated gasoline
program beginning in 1993.

12 }


18. Fort Collins-Loveland, CO MSA
19. Missoula, MT

20. Provo-Orem, UT MSA

21. Chico, CA MSA

22. Las Vegas, NV MSA

23. Fresno, CA MSA

24. Los Angeles-Anaheim-Riverside, CA CMSA
25. Modesto, CA MSA

26. Phoenix, AZ MSA

27. Reno, NV MSA

28. Sacramento, CA MSA

29. San Diego, CA MSA

30. San Francisco-Oakland-San Jose, CA CMSA
31. Stockton, CA MSA

32. Anchorage, AK MSA

33. Fairbanks, AK

34. Grant's Pass, OR

35. Klamath County, OR

36. Medford, OR MSA

37. Portland-Vancouver, OR-WA CMSA
38. Seattle-Tacoma, WA CMSA

39. Spokane, WA MSA

Section 211(m)(2) of the Act requires that the oxygenated gasoline
program apply to all gasoline sold or dispensed in the larger of the
CMSA or MSA. in which the nonattainment area is located. For
nonattainment areas not in a CMSA or MSA, the control area is the
nonattainment area. The requirements of the program shall apply to
every county, or partial county which is located in the CMSA, MSA, or
nonattainment areas. Table 2, compiled based on information from the
U.S. Census Bureau, contains a list of the counties that are covered by
these programs. States may rely on the list of covered areas by CMSA,
MSA, or nonattainment area that appear in. Table 2 for implementing
oxygenated gasoline programs in 1992.

This requirement has caused some concern. State officials in
Minnesota have expressed concern over the designation of the entire
Duluth MSA as requiring an oxygenated gasoline program. Most of
northeastern Minnesota is included in. the Duluth MSA. According to
state officials, much of this area is national wilderness area, and
therefore very rural and sparsely populated. The state believes that
compliance with the oxygenated gasoline provisions as proposed may
prove an »%nerous burden for the few gasoline marketers and retailers in
the area. : .

Congress specifically mandated in the Act that these programs be
implemented in "the larger of the Consolidated Metropolitan Statistical
Area (CMSA) in which the [CO nonattainment] area is located, or if the
area is not located in a CMSA, the Metropolitan Statistical Area in
which the area is located." Moreover, EPA does not agree that
compliance in northeastern Minnesota will be onerous since that area
already receives its gasoline from the Duluth area. Therefore, as

-1i


Several commenters have raised a concern regarding Litchfield
County, Connecticut. Section 211(m) of the Act provides that the
oxygenated gasoline program should apply in the entire Metropolitan
Statistical Area (MSA) or Consolidated Metropolitan Statistical Area
(CMSA) during that area's control period. Separate parts of Litchfield

“County are included in both the Hartford and New York City CMSAs. This
problem is compounded by the fact that these two control areas are
proposed to have different control periods. EPA believes that the
Connecticut SIP revisions should provide that each part of Litchfield
County be subject to the control period. applicable to. the MSA or CMSA
of which it is.a part. The state has indicated that this decision will
be acceptable to them.

Minnesota has requested a control period of October 15 through
February 14. Many gasoline marketers opposed starting or ending a
control period in middle of the month. Their opposition was based
upon the récordke ig and logistical problems “that a mid=month date ~~
would create. Given that one of the highest ambient readings in
Minneapolis occurred on October 15, EPA does not believe that the
October control period should be shortened to exclude the first two
weeks of October. Also, there were no exceedences in February in the
Minnesota ambient data. Therefore, EPA reaffirms its control period as
published 6n repruary 5, i992 = october through January. If the State
believes that February should be included, the State can consider
including it as part of the control period which will be included in
its SIP revision.

Several commenters including the Massachusetts Department of
Environmental Protection suggested that Boston should not be required
to implement an oxygenated gasoline program. These commenters did not
believe that the ambient monitoring data warranted implementation of an
oxygenated gasoline program in the Boston CMSA.

EPA does not agree with these commenters and thus strongly
believes that the Boston CMSA is an area which is required to implement
an oxygenated gasoline program by November 1, 1992.

EPA believes that the monitoring data collected in Boston in 1988
and 1989 was inadequate to properly characterize Boston's CO problem,
The CO microscale site in Boston was discontinued in June 1988 due to a
lost lease. The site was eventually moved to a new location and
resumed operation in january 1990. The new site has shown no
exceedences from January 1990 through January 1992. However, rerouting
of traffic patterns past this site for a major 10-year construction
project is scheduled'to begin in May 1992, and concentrations are
expected to increase. Since a microscale CO monitor did not operate
for 6 of the 8 calendar quarters during 1988 and 1989 and the previous
site had recorded CO exceedences in 1986, the Agency believes it is
reasonable to consider alternative data. The alternative data that the
agency has chosen to use is the calendar year data from 1986 and 1987.
Use of this data is consistent with current Agency policy and the
Agency's calaaification decision for Boston under Title I of the Act.

8


New Haven County (pt)
Ansonia Town
Beacon Falls Town
Derby Town
Milford Town
Milford City
Oxford Town
Seymour Town

Danbury, CT PMSA:

Fairfield County (pt)
Bethel Town
Brookfield Town
Danbury Town

Danbury City
New Fairfield Town
Newtown Town
Redding Town
Ridgefield Town
Sherman Town

Litehfield..county.... pt).
Bridgewater Town
New Milford Town

Jersey City, NJ PMSA:
Hudson County
Hoboken City
Jersey City
Middlesex-Somerset-Hunterdon, NJ PMSA:
Hunterdon County
Middlesex County
New Brunswick City
Perth Amboy City
Somerset County
Monmouth-Ocean City, NJ PMSA:

Monmouth County
Ocean County

Nassau-Suffolk County, NY PMSA:

Nassau County
Suffolk County

22


Ramsey County, MN

St. Paul City
Scott County, MN
Washington County, MN
Wright County, MN

Modesto, CA MSA

Stanislaus County
Modesto City
Turlock City

Phoenix, AZ MSA

Maricopa County

° Mesa City
Phoenix City
Scottsdale City
Tempe City

Provo-Ore! U

Utah County
Orem City
Provo city

aleigh- MSA

Durham County
Chapel Hill Town (pt)
Durham City
Franklin County
Orange County
Chapel Hill Town (pt)
Wake County
Raleigh City

Reno, NV _ MSA

Washoe County
Reno City

Sacramento, CA MSA

El Dorado County
Placer County
Sacramento County
Sacramento City
Yolo County
Davis City
Woodland City

28


Regulatory Negotiation
EPA used a Regulatory Negotiation Advisory Committee (Advisory

Committee) to aid in the development of the proposed* and
supplemental guidelines published on July 9, 1991 and February 5,
1992. For a discussion of the Regulatory Negotiation process as it
relates to development of these guidelines, please refer to the
February 5, 1992 Supplemental Notice.

Tir. Guidance and Rationale

Control Periods
In establishing an oxygenated gasoline program, the Act specifies

that oxygenated gasoline will be required during the portion of the
year in which the areas are prone to high ambient concentrations of
carbon monoxide. The control period. shall not be less than four
months. These -control- periods. are to-be-determined: by- the- we
Administrator. EPA may reduce the control period if a state can
demonstrate, based on meteorological conditions, that a reduced period
will assure that there will be no carbon monoxide exceedances outside
of such reduced period. Under section 211(m)(1)(B) of the Act, areas
with carbon monoxide design values of 9.5 parts per million (ppm) or
greater for-any twe-year-pericd-after -1989shall submit-SiIP revisions ~~
establishing an oxygenated gasoline program within 18 months of such
two-year exceedance period. EPA will address control period issues for
such areas as necessary.

In analyzing the control period issue, the Agency has focused
primarily on the ambient monitoring data from 1988 and 1989. The
Agency chose this time period because it is the time period specified
in § 211(m) of the Act for determining inclusion in the program. For
areas where the Agency believes that 1988-89 ambient monitoring data is
inadequate, the Agency has focused on the ambient monitoring data that
was used to determine that area's attainment status. EPA has also
considered more recent data in response to comments from state
officials requesting modified control periods.

EPA considered various approaches to calculating the period "prone
to high ambient concentrations of carbon monoxide," a phrase which the
Act does not define. The first approach taken by EPA analyzed the
ambient monitoring data by looking at the average carbon monoxide
concentrations which occurred in _8-hour overlapping periods (Approach
IT).

? 56 FR 31151 (July 9, 1991).
3.57 FR 4406 (February 5, 1992).


TABLE 2 - CMSA and MSA BY COUNTY!

Boston~Lawrence~Salem, MA-NH CMSA
Boston, MA PMSA:

Bristol County (pt)
Mansfield Town
Norton Town
Raynham, Town

Essex County (pt)
Lynn City
Lynnfield Town
Nahant Town
Saugus Town

Middlesex County (pt)
Acton Town
Arlington Town
Ashland Town
Ayer Town
Bedford Town
Belmont Town
Boxborough Town
Burlington Town
Cambridge Town
Carlisle Town
Concord Town
Everett City
Framingham Town
Framingham (CDP)
Groton Town
Holliston Town
Hopkinton Town
Hudson Town
Lexington. Town
Lincoln Town
Littleton Town
Malden City
Marlborough City -
Maynard Town
Medford City
Melrose City
Natick Town
Newtown City
North Reading Town
Reading Town

* A partial county is indicated by “(pt)”. following the county name. The cities and
towns that appear below the county name are those that are included in the program
area. .

15


Middleborough Town
Norwell Town
Pembroke Town
Plymouth Town
Plympton Town
Rockland Town
Scituate Town
Suffolk County
Boston City
Chelsea City
Revere City
Winthrop Town
Worcester County (pt)
Berlin Town
Bolton Town
Harvard Town
Hopedale Town
Lancaster Town
Mendon Town
Milford Town
Southborough Town
Upton Town

Brockton, MA PMSA:

Bristol County (pt)
Easton Town

Norfolk County (pt)
Avon Town

Plymouth County (pt)
Abingdon Town
Bridgewater Town
Brockton City
East Bridgewater Town
Halifax Town
West Bridgewater Town
Whitman Town

Lawrence-Haverhill, MA-NH -PMSA:

Essex County, MA (pt)
Amesbury Town
Andover Town
Boxford Town
Georgetown Town
Groveland Town
Haverhill City
Lawrence City
Merrimac Town
Methuen Town
Newbury Town
Newburyport City

17


II. Background

Section 211(m) of the Act requires states with carbon monoxide
(CO) nonattainment areas with design values of 9.5 parts per million or
more, based on data for the two-year period of 1988 and 1989,' to
submit revisions to their State Implementation Plans (SIPs). Such
states must individually implement an oxygenated gasoline program in
“the specified control areas requiring gasoline to meet a minimum oxygen
content of 2.7 percent by weight, subject to a testing tolerance
established by the Administrator.. This oxygen content requirement
applies during the portion of the year, referred to as the “control
period," in which the areas are prone to high ambient concentrations of
co. The length of the control period, as required by section 211(m) of
the Act, is to be determined by the Administrator and shall not be less
than four months in length. EPA may reduce the control period if a
State can demonstrate that because of meteorological conditions, a
reduced period will assure that there will be no carbon monoxide
exceedances outside of such reduced period. The oxygen content
requirement is to cover all gasoline sold or dispensed in the larger of
the Consolidated Metropolitan Statistical Area (CMSA) or the
Metropolitan Statistical Area (MSA) in which the nonattainment area is
located.

“This document provides EPA's guidance to states regarding the
establishment of control periods for oxygenated gasoline programs,
under section 211(m) of the Act, This guidance is a general statement
of policy. It does not establish a binding norm and is not finally
determinative of the issues addressed. Agency decisions in any
particular case will be made applying the law, applicable regulations
and guidelines on the basis of specific facts and actual action. The
proper control period will also be an issue during the notice and
comment rulemaking undertaken by EPA to review individual state
submissiéns of oxygenated gasoline programs as SIP revisions as
required by section 211(m).

To expedite Agency decisions in particular cases, a state
submitting a SIP revision which includes an oxygenated gasoline program
with a different proposed control period than the applicable control
period as specified in these guidelines should provide as detailed an
explanation as possible for the differences.

‘~The Agency has determined that the 1988 and 1989 data from
several areas is inadequate to properly characterize the ambient
concentrations of CO. Therefore, for these areas - Boston,
Cleveland and Washington D.C. ~- older, more representative data
has been used.


Tacoma, WA PMSA:

Pierce County
Tacoma City

Albuquerque, NM MS.

Bernalillo County
Albuquerque City

Anchorage, AK MSA

Anchorage. Borough
Anchorage City

Baltimore, MD MSA

Anne Arundel County
Annapolis City
Baltimore County
Baltimore City
Carroll County
Harford County
Howard County
Queen Annes County
Baltimore City

Chico, CA MSA

Butte County
Chico City

Colorado Springs, CO MSA

El Paso County
Colorado Springs City

ulutl -WI_MS.
St. Louis County, MN
Duluth City

El_ Paso, TX MSA:

El Paso County
El Paso City

26


Guidance on Establishment of Control Periods under Section 211(m) of
the Clean Air Act as Amended

SUMMARY: Section 211(m) of the Clean Air Act as amended by the Clean
Air Act Amendments of 1990 ("the Act") requires that various states
submit revisions to their State Implementation Plans (SIPs) and
implement an oxygenated gasoline program. This requirement applies to
all states with carbon monoxide (CO) nonattainment areas with design
values of 9.5 parts per million or more, generally based on data for
1988 and 1989. The oxygenated gasoline program must require gasoline
in the specified control areas to contain no less than 2.7% oxygen by
weight during that portion of the year in which the areas are prone to
high ambient concentrations of carbon monoxide, except that a state is
strongly encouraged to adopt an averaging program employing marketable
oxygen credits.

Section 211(m)(2) requires that the Administrator.specify the
portion of the year in which the area is prone to high ambient
concentrations of carbon monoxide: This portion of the year ("control
period") is to be not less than four months in length, unless the state
can demonstrate that based on meteorological conditions, a reduced
pericd will not result in exceedances outside of such.reduced period.

This document provides EPA guidance on control periods by area.
This document also discusses the geographic scope of the control areas.

The primary determinants of the control periods are the statutory
minimum of four months and data on exceedances of the carbon monoxide
standard at the design value monitor in the design value year.

FOR FURTHER INFORMATION CONTACT: Alfonse Mannato, (202) 260-9040
SUPPLEMENTARY INFORMATION:
I. Introduction

This document provides EPA's guidance on establishment of control
periods for oxygenated gasoline programs under section 211(m) of the
Act. Section II provides the background for this guidance, with
respect to chronology and the broad issues involved. Section III
presents EPA's guidance on control periods and rationale. Comments
received and. EPA responses to those comments are also contained in
Section III.


San Diego, CA MSA

San Diego County
Escondido City
San Diego City
Ss ie, WA M:

Spokane County
_ Spokane City

Stockt ie

San Joaquin County

Lodi City
Stockton City
Syracuse, NY MSA

Madison County
Onondaga County

. Syracuse City
Oswego County

Washington, DC-MD-VA_ MSA

District of Columbia
Washington City
Calvert County, MD
Charles County, MD
Frederick County, MD
Frederick City
Montgomery County, MD
Prince Georges County, MD
Arlington County, VA
Arlington (CDP)
Fairfax County, VA
Loudon County, VA
Prince William County, VA
Stafford County, VA
Alexandria City, VA
Fairfax City, VA
Falls Church City, VA
Manassas City, VA
Manassas Park City, VA

29


TABLE 1 - Guidance on Control Period
by Nonattainment Area

November 1 ~- Febru

Hartford-New Britain-Middletown, CT CMSA
Boston-Lawrence-Salem, MA-NH CMSA

Syracuse, NY MSA

Baltimore, MD MSA
Philadelphia-Wilmington-Trenton, PA-NJ-DE-MD CMSA
Washington, DC-MD-VA MSA
Greensboro-Winston-Salem-High Point, NC MSA
Memphis, TN-AR-MS MSA :
Raleigh-Durham, NC MSA
Cleveland-Akron-Lorain, OH CMSA
Albuquerque, NM MSA

El Paso, TX MSA

Colorado Springs, CO MSA

Denver-Boulder, CO CMSA

Fort Collins-Loveland, CO MSA

Missoula, MT

Provo-Orem, UT MSA

San Diego, CA MSA

Anchorage, AK MSA

Fairbanks, AK

Portland-Vancouver, OR-WA CMSA
Seattle-Tacoma, WA CMSA

Grant's Pass, OR

Klamath County, OR

Medford, OR MSA

\ October 1- April 30
New York-Northern New Jersey-Long Island, NY-NJ-CT CMSA

13°


Sherborn Town
Shirley Town
Somerville City
Stoneham Town
Stow Town
Sudbury Town
Townsend Town
Wakefield Town
Waltham City
Watertown Town
Wayland Town
Weston Town
Wilmington Town
Winchester Town
Woburn City
Norfolk County (pt)
Bellingham Town
Braintree Town
Brookline Town
Canton Town
Cohasset Town
Dedhan
Dover T
Foxborough Town
Franklin Town
Holbrook Town
Medfield Town
Medway Town
Millis Town
Milton Town
Needham Town
Norfolk Town
Norwood Town
Quincy City
Randolph Town
Sharon Town
Stoughton Town
Walpole Town
Wellesley Town
Westwood Town
Weymouth Town
Wrentham Town
Plymouth County (pt)
Carver Town
Duxbury Town
Hanover Town
Hanson Town
Hingham Town
Hull Town
Kingston Town
Lakeville Town
Marshfield Town

16