GUIDELINE SERIES
OAQPS NO.
1.2-011 (Revision.)
GUIDELINES FOR DETERMINING THE NEED FOR
PLAN REVISIONS TO THE CONTROL STRATEGY
PORTION OF THE APPROVED
STATE IMPLEMENTATION PLAN
US. ENVIRONMENTAL PROTECTION AGENCY
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina
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PSCISCWQJ
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TABLE OF CONTENTS
Page
I. Introduction 1
II. Responsibilities in Implementing Plan Revisions 5
A. Regional Offices 5
B. Headquarters 7
,:( C. Alternate Responsibilities 8
«*'•• III. Procedures for Determining Whether a SIP/Control
Strategy Needs to be Revised 10
A. Identification of Problem Air Quality Control Regions . 10
B. Review of Specific Conditions within Individual AQCR's . 14
v) 1. Evaluation of Data 15
C 2. Analysis of Control Strategy 18
« 3. Available Analytical Techniques 21
" (a) Abbreviated Roll-back Procedure 21
(b) Modified Roll-back 23
\J (c) Diffusion Modeling . • 23
s C. Determination for Need for Plan Revision 25
IV. Procedures for Requiring Plan Revision 26
A. Plan Revision Documentation 26
B. Notification of State and Public 26
1. Federal Register Notice 27
2. Other Federal Register Actions 32
3. Letter to the Governor 33
C. Plan Submittal 34
V. Overview of Necessary Action in Relation to Substantially
Inadequate SIP's 35
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I. INTRODUCTION
Section 110 (a)(2)(H) of the Clean Air Act, as amended requires
that State Implementation Plans (SIP's) provide "for revision, after
public hearings, of such plan (i) from time to time as may be necessary
to take account of revisions of such national primary or secondary ambi-
ent air quality standard; or the availability of improved or more expe-
ditious methods of achieving such primary or secondary standards; or
(ii) whenever the Administrator finds on the basis of information avail-
able to him that the plan is substantially inadequate to achieve the
national ambient air quality primary or secondary standard which it
implements". (Emphasis added)
While the Act specifically identifies two reasons why SIP's can
and must be revised, this guideline deals mainly with the second category,
i.e., plan revisions to the SIP which are deemed necessary on the basis
of information which indicates the approved SIP control strategy is sub-
stantially inadequate to attain and maintain the national standard it
implements.
It is the Regional Administrator's responsibility to identify any
SIP which is substantially inadequate to attain national standards and
to call for a plan revision where necessary. Such determinations are
to be made in Fiscal Year 1976 for all areas of the nation (i.e., both
AQMA's and non-AQMA's) for each criteria pollutant (i.e., TSP, S02> CO,
0 and N09). Calls for revision to those existing SIP's which are sub-
X L.
stantially inadequate for attainment must be publicly announced without
proposal prior to July 1, 1976. These calls for revisions must specify
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the schedule for submission of revisions and must require that, to the
extent needed to meet national primary standards, all emission limitations
which it is reasonable to anticipate will be achievable within a reason-
able period of time must be submitted by the State by July 1, 1977.* Any
other control measures (generally referring to transportation controls
and land use measures) necessary for attainment and maintenance must be
submitted by the State by July 1, 1978. (NOTE: This is not intended to
imply that some land use and transportation measures are not considered
reasonable. These measures, though considered reasonable, generally
require more time to implement due to need to obtain enabling legislation.)
While the Act requires attainment of both primary and secondary
standards, priority attention shall be addressed to attainment of primary
standards. However, it is recommended that when plan revisions are
called for attainment of primary standards that they also be adequate
to provide for the attainment of secondary standards. Further, any plan
revision for attainment of national standards shall also consider
maintenance of such standards.
The decision to call for a plan revision should be made only after
detailed analysis of the status of air quality; the restrictiveness
of the existing regulations; the status of major compliance actions and
after thorough discussion with all pertinent program elements in the
Regional Office and with the affected State and local control agencies.
*Thus "technology forcing" based upon reasonable (not crystal ball) projec-
tions should be required wherever necessary to attain and maintain the
primary standards.
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The Agency must exercise good judgment in determining whether the
control strategy portion of an approved SIP is inadequate to achieve
national standards on a timely basis. It is the Agency's policy to
request such plan revisions only where they are clearly necessary. To
declare that a SIP is substantially inadequate will imply a need for
new and more stringent emission limitations. It will take some time to
develop such limitations. Pollution sources might use this situation
to resist coming into compliance with existing regulations and thus,
ongoing abatement actions could be inhibited. Further, frequent revisions,
particularly where they affect emission control requirements, are unde-
sirable in that they confront source owners with a "moving target".
Another factor to be considered is that any plan revision submitted
by a State that changes some part of the SIP or which adds a new part
could result in a Section 307 challenge by the affected sources to the
changed or added part. Such action may'del ay enforcement of the new
requirements. (Section 307 provides for a process of judicial review of
the Agency's action in approving or promulgating any implementation
plan or revision thereof.) The Office of Enforcement's experience
with §307 suits indicates that substantial delays in enforcement can
result from such challenges. Therefore, this reason alone is good
cause to minimize changes in regulations in the plan until present con-
trol requirements are fully implemented and any revision is clearly
necessary.
This guideline addresses the procedures to be followed in determining
those areas that mav not attain national standards (i.e., both Air
Quality Maintenance Areas (AQMA's) and non-AQMA's). Once it has been
determined that a SIP is substantially inadequate, the degree of analysis
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needed by the State to demonstrate attainment and maintenance varies depen-
ding upon whether the area is designated an AQMA or not. The analysis
procedures for AQMA development are found in Part 51, Subpart D (Main-
tenance Regulations). These Maintenance Regulations will allow the
Regional Administrator to modify certain analysis requirements by follow-
ing specified procedures. Procedures for States to demonstrate attainment
in non-AQMA areas are those existing Part 51 regulations on SIP
development.
This guideline does not address procedures for areas where only
a maintenance plan (i.e., no attainment plan necessary) is needed.
Procedures for such maintenance plans are found in Part 51, Subpart D
(Maintenance Regulations). It should be noted that calls for SIP
revisions where only a maintenance- plan is needed (i.e., where no
attainment plan is needed) need not be accomplished by July, 1976.
The Regional Administrator may schedule the call for a maintenance plan
at any time for those areas that do not have an attainment problem but
which may need a maintenance plan.
This guideline sets forth (1) the responsibilities of headquarters
and Regional Office personnel in relation to determining the need for
and calling for plan revisions, (2) the procedures for determining when
a plan revision to the control strategy portion of the SIP is necessary,
and (3) the procedures for notifying the State that a plan revision is
necessary. EPA procedures for approving/disapproving SIP revisions
submitted by States are not included in this Guideline but are contained
within OAQPS Guideline 1.2-005A (as revised).
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RESPONSIBILITIES CONCERNING PLAN REVISIONS
A. REGIONAL OFFICES
The Regional Office is responsible for reviewing available infor-
mation to determine if the approved control strategy is substantially
inadequate to attain and maintain the national standards. In making
this determination, it is important that the various program elements
within the Regional Office (OAHM, S&A, OE) be involved in the evalu-
ation and decision-making process. The various activities
required to determine the adequacy of the approved SIP generally involve
the responsibilities of these three Divisions. For example, the analysis
to determine the inadequacy of the SIP requires (1) a determination of
the validity and representativeness of the ambient air quality data
(S&A activity), (2) a determination of which portions of the control strategy
need to be revised and what new regulations should be recommended (OAHM
activity), and (3) a determination of the impact of these recommended regu-
lations on on-going enforcement activities (OE activity). Interdivisional
coordination is therefore essential to make the most effective call for
plan revision. Similarly, coordination, as appropriate, with State and
local agencies can also result in a more effective plan revision.
Specific Regional Office responsibilities require that each SIP
for each pollutant (i.e., particulate matter, sulfur dioxide, carbon
monoxide, photochemical oxidants and nitrogen dioxide) be reviewed during
Fiscal Year 76 to determine if any such SIP is substantially inadequate
to attain and maintain national standards. In cases where the SIP is
determined to be substantially inadequate, the Regional Office must:
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(1) By July 1, 1976, notify the State, and announce in the Federal
Register that the control regulations contained in the SIP for the
pollutant in question are inadequate to attain (and in most cases to
maintain) national standards and that a plan revision is necessary. A
call to the State for a plan revision should be as specific as possible
in suggesting what new or revised regulations are needed. Further, the
call for plan revision should establish a time schedule for the State to
submit an indication of its intent to develop the necessary plan revision
and also for the submittal of the actual plan revision. (See Chapter IV
for additional details.)
(2) By July 1, 1977, the State must submit a plan revision that
includes, to the extent needed to meet national primary standards, all
emission limitations which it is reasonable to anticipate will be achievable
within a reasonable period of time. Also, any other control measures
(generally referring to transportation controls and land use measures)
necessary for attainment and maintenance must be submitted by the
State by July 1, 1978.
On October 15, 1973, the Administrator delegated his authority to
request plan revisions from States to the Regional Administrators through
EPA Order 1270.5 (see Appendix C). In cases where a plan revision is
requested by The Regional Office, the Assistant Administrators for OAWM
and OE should be notified.*
*NOTE: It has been recommended that EPA Order 1270.5 be amended to read
as indicated. Presently the order requi res the RO's to obtain the concur-
rence of the AA's on significant plan revisions. The order also presently
states that concurrence should be obtained on other plan revisions.
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Once the plan revision has been submitted by the State, the Regional
Office is further responsible to review, to recommend approval/disapproval
and promulgation and to prepare the Federal Register package associated
with any measures which have been determined to be necessary to assure
that the national standards will be achieved. These procedures are
contained in the July 22, 1975 Strelow/Legro memo to all Regional Adminis-
trators and will be incorporated in OAQPS Guideline 1.2-005A for proces-
sing SIP revisions.
B. HEADQUARTERS (OAWM/OAQPS/OTLUP AND OE/DSSE/MSED)
OAWM/OAQPS/OTLUP will provide policy and technical assistance to the
Regions concerning the plan revision issue. OAQPS has prepared various
policy guidelines concerning operational procedures and the criteria
to be considered in calling for plan revisions. Various technical
documents are also available to assist in the analysis of the adequacy
of the existing control strategy. For example, many of the technical
guidelines prepared primarily for the development of maintenance
plans such as Volume 11 and Volume 12 dealing with data analysis
and modeling respectively can be of value when considering plan
revisions for the attainment and maintenance of national standards.
In addition, guidance on control regulations and "cookbook" type manuals
that provide step-by-step guidance on the development of approvable SIP's
for NO and Ov will be provided during the Fiscal Year. Further, OAQPS
A A
will provide additional assistance as appropriate to the Regions in the
plan revision area.
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The Office of Transportation and Land Use Policy (OTLUP) is
a staff office of OAWM which provides technical support to the Regional
Offices in the development, evaluation and promulgation of transporta-
tion and land use related SIP actions. As such, OTLUP will provide
policy guidance to the Agency on land use and transportation measures
(see August 5, 1975, DRAFT policy memo on subject) and will participate in
the review of such control strategies being implemented by the Regions
as outlined in OAQPS Guildeline No. 1.2-005A (Revised)
The Office of Enforcement (DSSE and MSED) will provide appropriate
assistance to the Regions regarding enforcement policy with respect to
stationary sources and transportation control plan elements, respectively.
C. ALTERNATE RESPONSIBILITIES
The responsibilities within the Agency are somewhat different in
those cases where plan revisions are necessary to take account of new
or revised national standards. In this case, OAWM has the primary
responsibility of preparing and publishing in the Federal Register
(1) the new or revised national standards and (2) specific guidelines
on what actions States need to take to develop, adopt and submit an
approvable plan to implement the new or revised standard. In general,
all States will be required to submit a plan for a new national stan-
dard or will be required to augment and/or revise their existing SIP's
to consider a revised national standard. After OAWM has published
guidelines for the development of approvable SIP's, the Regional Offices
are then responsible to assist States in the development of SIP's, to
develop plans where States fail, etc.
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In situations where the SIP regulations (40 CFR Part 51) are modi-
fied in such a way as to affect the control strategy requirements (such
as the action in relation to maintenance of standards, 40 CFR 51.12,
June 18, 1973) OAWM and Regional Office responsibilities are identical
to those described for a new or revised standard.
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III. PROCEDURES FOR DETERMINING WHETHER A SIP/CONTROL
STRATEGY NEEDS TO BE REVISED
A. IDENTIFICATION OF PROBLEM AIR QUALITY CONTROL REGIONS
It is difficult to develop comprehensive guidelines for all cases
on exactly how to determine whether a control strategy will need to be
revised. While there may be a few situations where it is obvious that
a plan revision is necessary, in general it will be a difficult task to
determine that a plan is substantially inadequate to attain national
standards. The basic problem is to determine whether AQCR's are pro-
gressing satisfactorily toward attainment of national standards
as sources come into compliance with emission limitations contained
within the SIP.
Some factors that could be considered in making a determination as
to whether a SIP is substantially inadequate are as follows:
1. Factors favoring a finding that the SIP is not substantially
inadequate:
a. Available data provide a reasonable expectation that
NAAQS have been or will be achieved by the currently approved
SIP under provisions of the existing control strategy.
b. The most recent air quality data are below or not far
above NAAQS.
c. Much abatement work is ongoing or yet to be completed
under existing regulations.
d. Air quality and emission data are not yet extensive in
terms of time and geographical coverage.
e. Air quality levels have varied erratically up and down
in recent years and a clear trend is not yet determinable.
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f. Emission control regulations have been made more stringent
or more compehensive in the past 1 to 3 years but are not yet fully
implemented.
g. Existing regulations are very stringent -- at or border-
ing on a requirement that all reasonable control measures thet can be
achievable arc being used.
h. Major reductions in emissions have been made in the past
year or two and perhaps more reductions are programmed for the
near future.
i. The governmental air pollution control program has grown
substantially in the past few (1 to 3) years and enforcement
actions are being intensified.
2. Factors favoring a finding that the SIP is substantially inadequate:
a. There is good evidence that compliance with existing
regulations will not result in achieving NAAQS by the existing
attainment date.
b. Recent air quality levels are substantially above NAAQS.
c. Most existing regulations have been fully implemented;
future improvement in air quality under existing regulations
will not be substantial.
d. Air quality levels over the past few years show an evident
trend which, in consideration of abatement yet to occur, shows
clearly that NAAQS will not be attained by existing control
measures.
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e. Air quality and emission data are generally accurate
and extensive as to time series and geographic coverage.
f. Emission control regulations have not changed greatly
in recent years.
g. Existing regulations are not particularly stringent
and do not include all emission limitations which it is reasonable
to anticipate will be achievable within a reasonable period of time.
h. There has not been much change in air quality over the
past 1 to 3 years (and levels are above NAAQS).
i. Governmental control activities have been reasonably
adequate for the past few years (1 to 3) and regulations are
probably enforced well.
Of course, a number of factors other than air qualtiy and emission
data must be considered in the determination of the need fp_r a plan
revision, and/or the tining of the call for plan revision. These factors
include the following:
1. The Clean Air Act requires that SIP's which are substantial1y
inadequate to attain national standards be revised. Simply because
ambient air quality data exceed a national standard by 10% or 15% does
not in itself indicate an immediate need for a plan revision. Clearly,
the normal variation of ambient air quality due to meteorological condi-
tions, etc., may cause such a condition to exist. The requirement of
substantially inadequate provides the Regional Office with flexibility
in assessing the need for, and especially the timing of a call for plan
revision.
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2. The Agency has submitted to Congress a number of amendments
to the Clean Air Act. The most pertinent amendments affecting the call
for plan revisions involve:
(a) The TSP Act Amendment, and
(b) The Transportation Control Plan Act Amendment.
These two amendments are very similar and if accepted by Congress,
it is anticipated that they would provide extensions to attain the
national standards and provide guidance with respect to those areas
where unreasonable controls are needed to attain standards. Additionally,
the Senate is considering a new Section 120 to the Clean Air Act which
would require the establishment of a planning organization in any area
where SIP's are inadequate to attain and maintain NAAQS. Since these
amendments are presently being discussed by the Congress, calls for
plan revisions should be postponed until after the amendments are
fully considered and adopted by the Congress. It is presently estimated
that the revised amendments may be available toward the latter part of
1975. (NOTE: It is recommended that calls for plan revision be post-
poned, however the analysis necessary to determine the extent of the
problem should proceed.)
3. In some cases, little or no ambient air quality data exist
to allow for a determination of the adequacy of the SIP. For example,
in many cases, nitrogen dioxide data may not be available due to the
controversy concerning the original reference method. While adequate
and sufficient data should exist in many major urban areas (due to the
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special field projects over the past few years) there may be some areas
where sufficient data are not available. In these cases, any decision on
attainment and the need for plan revis ions..may have to be delayed from
the Fiscal Year 76 time period.
B. Review of Specific Conditions within Individual AQCR's
To attain national standards, EPA policy is that air quality levels
throughout an AQCR must be equal to or below (i.e., better than) national
standards (see OAQPS Guideline Document 1.2-008, Revised August 22, 1974).
In many cases, much of an AQCR may have ambient air quality at or below
the national standards, however, a few sites may have air quality that
is above the national standards. A review of the specific conditions that
cause these high ambient concentrations on a site-by-site basis will allow
the Agency (a) to determine if a pl-an revision is necessary, and (b) to
call for plan revisions that address localized problem areas. Control
strategy revisions based on site-by-site reviews may not be possible in
many large urban areas, especially for particulate matter, where non-
attainment of standards may be a relatively widespread problem with perhaps
more than 50% of the monitoring sites above the national standard. In
these cases, it is more appropriate to review the entire control strategy
for the area (i.e., AQCR, county or some other geographic area). It is
suggested, however, that even in such urban areas each site be
examined to determine the quality of data being collected and to determine
if local sources excessively bias ambient measurements.
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Prior to the review of the adequacy of the control strategy, it
is important to investigate the available ambient air quality to deter-
mine (1) its validity and (2) its representativeness (i.e., what does
the data represent and how should such data be used as the basis for
requiring a plan revision?).
1. Evaluation of Data
The validity of the air quality data is a major item in the review
of potential problem sites. Monitoring and Data Analysis Division, OAQPS,
has prepared several guidelines to assist in the certification and inter-
pretation of air quality data (See Appendix B).
While EPA should generally be confident of the validity of the air
quality data submitted by State and local agencies, it is also necessary
to review the validity of specific data, especially those data which
indicate the need for a plan revision. The National Air Data Branch (NAD3)
periodically questions State and local agencies concerning aoparent data
anomalies via a form letter; however, a more thorough investigation of the
ambient data which indicates a problem would be conducted by the Regional
Office. The Regional Office should refer to the guidelines mentioned above
for the specific items that should be reviewed to assure valid data.
Briefly, the review should determine:
(a) Are the proper numbers and kinds of monitoring equipment
operating in the area?
(b) Are monitoring sites properly located in accordance with
published guidelines?
(c) Are they properly calibrated and properly operated?
(d) Are the collected data properly validated?
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(e) Have all abnormal values been checked?
(f) Have peak concentrations which are of most concern been
evaluated to determine their accuracy?
(g) Are the data accurate and valid and can they withstand a
legal challenge of their validity?
In cases where data are questionable, they should generally not be
used in control strategy development. It is anticipated that many Section
307 challenges will be filed in relation to revised SIP's. Therefore, it
is prudent to base the need for plan revisions on valid and defensible
data.
If it is determined that the air quality values are valid, then a
further review of the data should be made to determine if the data are
representative and if such data should serve as the basis of a revised
control strategy. The review of the data should attempt to determine
if a nearby source(s) overly impacts on a monitoring site.
The purpose of determining the "representativeness" of the data is
so that the control regulations that will be adopted will affect the
sources that cause high ambient concentrations. For example, if an
ambient monitor is overly influenced by street dust, it is improbable
that new control regulations which olace stringent requirements on
stationary sources will have a beneficial impact on the ambient levels
at the site. Similarly, requiring particulate matter control on fuel
combustion sources may not provide for attainment where recorded ambient
levels in excess of national standards are due to windblown fugitive dust.
It is recommended, therefore, that each site be examined to determine
its "representativeness" for use in the development of a general control
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strategy, and/or to determine the sources which the site does represent.
If a site is source oriented, the data collected at that site should be
used to determine the degree of control that source may need to attain
standards but should not be used as the basis for control regulations
for all sources with the AQCR.
In examining the representativeness of the data, it may be determined
that unusual conditions existed such that the data should not be used in
control strategy development. For example, if the frequency and duration
of inversions and stagnations were unusually high, air quality levels could
be higher than normal. Unusually warm or cold weather will result in a
change in fuel use which may increase ambient levels above normal. If
conditions conducive to higher pollution levels were so unusual as to
not be expected to occur again for many years (e.g., 5 or 10 years), it
may be appropriate to discount high pollution levels occuring during such
rare events. Other examples of unusual events include dust storms, fires
or unusual control equipment malfunction or shut-down which could tempor-
arily cause abnormally high ambient concentrations. Generally, data
collected during such situations should not be_ used as_ a_ basis for requir-
ing additional control erf stationary sources.
In the investigation of air quality data, the Regional Offices
should obtain the very latest air quality concentrations for the s_jte_ ir\_
question. It may be necessary to obtain these data from the State or
local agency if they are not included in SAROAD. (In these cases, the
new data should be submitted to SAROAD to assure the availability of
the latest data to all users.) The data used for the review of the
adequacy of the SIP need not be for a calendar year, but should represent
the most recent 12 months (or four quarters) for which data are available.
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While OAQPS Guideline 1.2-008 points out that compliance with annual
NAAQS shall be based upon calendar year data, it further points out
that a continued appraisal of air quality on a quarterly basis is
needed to assess the status and progress with respect to the adequacy
of the SIP. Hence, it is not inconsistent with other Guidelines to
use non-calendar ambient data to determine if a SIP is inadequate
to attain standards.
2. Analysis of Control Strategy
With the addition of the latest air quality data, a comparison of the
trends in air quality levels at the site in question with the air quality
trends noted at other sites within the Region (State, city or other areas
where comparable results should exist) should be made. If the increase
or decrease is significantly different from that at the other sites, it
would appear that a localized problem exists.
For the purposes of this guideline, consider three hypothetical
cases:
Case 1: Assume that one site is above the national standards in an
AQCR. In this case, it is recommended that a review of the emission data
and compliance status of sources within the immediate vicinity of
the site in question (sav within a 1 to 3 mile radius--particulate
matter, sulfur dioxide, and CO; oxidant would require a much larger
area) be made. Points to consider include:
(a) Are all sources, both point and area sources, included in
the inventory?
(b) Are some sources presently uncontrolled? If so, are there con-
trol regulations with which these sources must ultimately comply?
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If not, do these sources impact sufficiently on the site to warrant
a recommendation for a plan revision to require further emission
limitations on these sources?
(c) If the sources reviewed in (a) have applicable regulations that
they must adhere to at some later date, is the anticipated emission
reduction adequate to reduce ambient levels to below the standard?
(d) Do the sources reviewed in (a) have applicable emission limi-
tations they must presently comply with? Are the sources in compli-
ance with the regulations? If so, will additional emission reductions
be needed to provide for the attainment of the national standard? If
the sources are not in compliance with the emission limitation, is the
source on a compliance schedule? Should EPA/State enforcement action
be initiated against the source?
(e) Have the source emissions in the vicinity of the site in ques-
tion increased significantly? Is a plan revision necessary to com-
pensate for increases in emissions? What action is needed in relation
to assuring that the State adequately considers ambient standards
prior to approval for construction of new, sources?
Case 2: Suppose the attainment date for an AQCR has passed. If the
air quality data are found to be above the NAAQS, it would seem at first to
indicate that the SIP needs revision. However, the Regional Office should
consider some other items prior to requesting a revision:
a. Are all affected sources in compliance with the SIP?
b. Has sufficient time elapsed for recent emission reductions to
be reilecteci in the air qualtiy data?
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c. Have any of the sources affecting the site received a variance
from the State? Was such a variance legal? If not, is enforcement
action necessary?
d. Are new sources affecting the site? Is the State giving proper
consideration to the NAAQS when approving new sources?
e. Should EPA action be taken to implement new source review
procedures?
Case 3: Suppose that an AQCR was originally classified Priority III
because no data were available to indicate if any problems existed. More
recent data however show that an air quality problem does exist. What action
should be taken?*
In this case, the regulatory structure of the SIP should
be reviewed since the SIP may contain emission control regulations ade-
quate to attain NAAQS. Though the AQCR was classified Priority III, the
example region approach may have been used for plan development resulting
in the adoption of State-wide regulations. The implementation of these
regulations may be adequate to attain NAAQS.
*NOTE: In the Draft of this Guideline that was circulated for review in
August, 1975, a discussion was provided which indicated that the AQCR iden-
tified above should be reclassified to indicate that an air quality problem
existed. Many commentors correctly noted that this was contrary to pre-
vious guidance on the recommended use of the Priority Classification System
(8/12 memo from Mr. Steigerwald to Mr. Holman, Region I). Since that memo,
additional discussions have lead to the belief that the Priority Classifi-
cation Scheme is useful and should be retained. Consequently, work is
underway to improve the classification system (e.g., to delete regulatory
requirements associated with it and to revise it to indicate current
Agency priorities). Additional information will be provided to the Regional
Offices for review and comment prior to finalization of a modernized classi-
fication scneme.
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3. Available Analytical Techniques-1
Predictions of future air quality, especially when abatement actions
are still going on or to be taken, are not precise. Therefore, any finding
on what future air quality will be is not precise and a finding that a SIP
is substantially inadequate at this time should consider a number of variables
rather than be based on simplistic calculations. Various analytical tech-
niques are available to assess the source/receptor relationship, and the ef-
fect of emission control limitations on this relationship. Some of these
techniques are described below:
a. Abbreviated Roll-back Procedure
This procedure is useful when the amount of additional emission reduc-
tion expected between the present time and completion of actions to assure
compliance with all existing regulations can be readily calculated, such as
when only a few sources remain out .of compliance. In using this procedure,
the following calculations are made:
(1) Prepare an estimate of the emission reductions that will occur
because of completion of remaining abatement actions. For example,
25 sources may remain out of compliance. Their present emissions
are 140 tons per day. When controlled in accordance with existing
regulations, their emissions will total 40 tons per day (100 tons
not yet controlled).
(2) Prepare an estimate of total emissions in the area as of
the present time, either by:
(a) Updating the on-going emission inventory, or
*Though not discussed in detail herein, it is assumed that a current
emission inventory for point and non-point source and source compliance
information is available. Point sources are generally defined as those
sources with a potential for emitting 100 tons or more of a criteria
pollutant.
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(b) Taking the original SIP estimate of emissions after the
control strategy is implemented and add to it the "not yet
controlled" value from Step 1. For example say that present
emissions are 1000 tons per day.
(3) Estimate future air quality after remaining abatement is
accomplished by use of the proportional model, using the following
formul a:
Future AQ _ Present emissions - emissions yet to be controlled
Present AQ Present emissions
assume present air quality is 90 ug/m
Future AQ = 1000 - 100
90 ug/m3 1000
Future air quality = 81 ug/m3
If the pollutant of concern involves a background (rural area) factor,
it must be considered. For example, assume the pollutant is particu-
late matter and background levels are 30. Future air quality is then
calculated, in this example, to be:
Future AQ - Background = 1000 - 100
Present AQ - Background 1000
Future AQ - 30 _ 900
90-30 ug/m3 1000
Future air quality = 84 ug/m3
Such a procedure is useful in that it considers current air quality,
emission and compliance information to assess the potential of future
emission reductions. However, other more sophisticated techniques are
available to relate emissions to air quality. It is generally recom-
mended that in determining the need for a plan revision a more detailed
approach be utilized in defining the relationship between emission
reductions and air quality.
22
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b. Modified Rollback
The modified rollback model represents an improved form of the
basic rollback model and allows for direct consideration of additional
parameters not considered by the basic rollback model. The modified
rollback models can be used manually or by computer depending on the
complexity of the study area. They are available in four basic forms
which are progressively more detailed and accurate and progressively
require a more extensive data base and computation time.
The first form of the modified rollback models extends the basic
rollback to multiple categories of sources, which may experience differ-
ing rates of growth and degrees of control. The second modified form
extends this multiple-source version to include the effects of average
stack heights for the various categories. The third model includes the
radial distance from source to receptor, and the fourth model adds wind
direction frequency. The technique is described in a paper entitled
"Rollback Modeling - Basic and Modified" by Noel de Nevers and Roger
Morris, and is further summarized in Volume 12 of the Maintenance Guide-
line Series: Applying Atmospheric Simulation Models to Air Quality
Maintenance Areas.
c. Diffusion Modeling
This is the preferred predictive tool available in relating emissions
to air quality data. A number of diffusion models, Air Quality Display
Model (AQDM), the Implementation Planning Program (IPP), etc., are avail-
able for defining urban situations on an annual basis and are listed in
Table 1 (see OAQPS Guideline Document No. 1.2-031, September 1974 for
detailed discussion). Diffusion models such as these, as well as technical
23
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Table 1
Summary of Simulation Model Characteristics
Model
Name
Rollback
Appendix J
Miner-
Hoi worth
Hanna-
Gifford
Hanna-
Glfford
Pollutant
Specifi-
cation
Any
°x
SO, JSP
2
SO-.TSP
CO2
SO,.TSP
Averaging
Time
Specifl- Emission
cation Data
Any
1 Hour
1 Hour,
Annual
Annual
1-24 Hour
1
1
1
1
2
Meteor-
ological
D.Ha
1
1
3
2
5
Concen-
tration.
Estimates
3
3
3
3
,
2
Ease of
Use
1
1
1
1
2
Avail-
ability
1
1
1
1
1
Rell-
ab1 1 1 ty
3
3
1
1
1
Applicability
to AQM
3
3
3
3
2
w. Point Source
model
w. HIWAY
AQDM
SCIM*
APRAC-1A
SAI*
SJ,,TSP
co2
S02,TSP
SJj.TSP
CO
CO,N02,0X
1-24 Hour
1-24 Hour
Annual
1-24 Hour
1-24 Hour
1-10 Hour
3
3
3
3
3
2
5
5
4
5
5
5
1
1
1
1
1
2
2
2
3
3
3
3
2
2
2
3
2
3
1
1
1
2
2
. 2
1
1
1
1
1
2
*lhese models are currently 1n a developmental and debugging phase; they are not available for general
distribution as computer programs.
Key to Table 1
rn, nx. NO,)
A. Pollutant Specification
Any pollutant
Specific Pollutants (sii,
B. Averaging-time Specification
Any averaging-time
Annual Average
1 to 24 hour Average
C. Emission Data
1. Area-wide Emissions Total
2. Total emission distributed as finite area sources
3. Detailed point, line and area sources
D. Meteorological Data
1. None
2. Average wind speed
^t Average wind speed and mixing height
«. »'• Frequency distribution of wind direction, wind speed,
stability and mixing height
5. Hourly variations of wind direction, wind speed, stability'
and mixing height
24
H.
Concentration Estimates
1. Estimates at any specified point
2. One estimate for each area source grid
3. One estimate applicable to entire AQMA
Ease of Use
1. Slide-rule
2. Snail computer effort
3. Major computer effort
Availability
1. r'~n literature
2. National Technical Information Service
3. EPA, upon request
Reliability
1. Can be verified and calibrated
2. Verification 1s Incomplete, possibility of calibration
1s uncertain
3. Questionable, acceptable for crude estimates only
Applicability to AQM
1. Can distinguish between specific source and land use types
2. Can distinguish between land use types only
3. Considers no distinction between sources or land uses
-------
assistance to operate them on the EPA UNIVAC 1110 system is available
from MDAD, OAQPS. Point source models are also available for single
source short-term (1-hr and 24-hr) situations. Diffusion modeling
requires detailed emission, air quality and meteorological data to
mathematically simulate the emission/air quality relationship for a
given AQCR. While there are certain limitations which restrict the
use of diffusion models (lack of data, severe topographic variations,
etc.), the method does provide the best available approach to predict
resulting ambient levels caused by the application of emission limita-
tions on emission sources. (See note)
C, Determination for Need for Plan Revision
During the technical analysis to determine if a plan revision is
appropriate, the Regional Office should consider the impact of calling
for a plan revision in relation to ongoing enforcement programs. The
possibility of a Section 307 challenge, and its effect on compliance
and enforcement should be discussed and considered. While plan revi-
sions should be sought where determined necessary, attempts should be
made where possible to minimize the impact of plan revisions on enforce-
ment activities.
NOTE: Both rollback and diffusion modeling techniques have been
discussed in this document. It should be noted that the Agency
proposed in the Federal Register^ on September 14, 1973, that future
control strategy development shall be based upon diffusion modeling
analysis. This position may be somewhat modified prior to promulgation.
Further, additional guidance on modeling techniques Will be published in
Appendix A, of the Part 51 regulations. For purposes of preliminary
analysis of the problem AQCR's, rollback techniques may be used; however,
when the revised control strategy is developed by either the State or
EPA it is strongly recommended that diffusion modeling be utilized
in most cases. In other words, rollback is adequate for the decision
to call for a plan revision but is not as good as diffusion modeling
as the basis of costly regulations that can be challenged under Section 307.
25
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IV. PROCEDURES FOR REQUIRING PLAN REVISIONS
If the analysis of the problem indicates that a revision to the
control strategy is needed, the following actions are necessary:
A. PLAN REVISION DOCUMENTATION
The Regional Office should document the reason why the plan revision
is necessary, providing a reasonable amount of detail on the discovery
analysis performed to determine the need for the revision. To the ex-
tent practical, the Regional Office should suggest specific source(s)
or source categories or regulations which should be considered under the
plan revision. While it is hoped that the approved SIP will be adequate
to attain the national standard on an AQCR-wide basis, it is likely that
portions of some AQCR's will need further controls to achieve
the standards. In other AQCR's, area-wide changes in the SIP will
be needed. Recommendations for SIP revisions should therefore be made as
to the specific geographic area in which the revision is needed, i.e.,
by AQCR, by county, by "hot spot" areas or in some definable area where
an air quality problem has been noted.
The analysis which is performed to determine the need for a plan re-
vision should be discussed with appropriate State and local officials.
Similarly, the particular regulations which should be revised or added
should be identified, to the extent practicable at this stage of evalu-
ation, with appropriate State and local officials.
B. NOTIFICATION OF STATE AND PUBLIC
The Regional Offices should first confer with the State and/or local
agencies involved and advise them of the need for plan revision and explore
with them, any particular regulations which clearly need revision or
26
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need to be added and those which do not. Subsequently, the Regional Admin-
istrator should officially notify the State that a revision is necessary
via a letter to the Governor followed by a Federal Register notice.
1. Federal Register Notice
Various Federal Register actions will need to be taken in relation to
advising the State and the public that the Agency has determined that a
plan revision is necessary. The first Federal Register action involves
a Federal Register notice indicating EPA's determination of an SIP defici-
ency and requesting corrective action on the part of the State agency.
The Federal Register notice can be considered as an "open letter" to
the State and it should contain a summary of the detailed analysis on which
the need for the plan revision is based. Specifically, the notice should
discuss the following:
a. Specific reasons why the plan revision is necessary;
b. Recommendations as to the actions which appear to be necessary
to correct the deficiency, if known, e.g., what sources appear to cause
the need for further controls; what regulations, if any, should probably
be revised or added; and which regulations appear to be adequate.
c. The Federal Register Notice should also indicate that the plan
revision should include the degree of emission reduction necessary
to offset emission increases that can reasonably be expected to result
from projected growth of population, industrial activity, motor
vehicle traffic and other factors that may cause or contribute to
increases in emissions; (NOTE: In non-AQMA areas, it is not necessary
to require the detailed consideration of growth as is required for
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AQMA's. In non-AQMA's, the FMVCP, NSPS, and the review of new source
procedures should generally be adequate to maintain NAAQS. However,
the plan revision should consider growth in an area and, where necessary,
include the degree of emission control to provide for continued main-
tenance of NAAQS.)
d. The Federal Register Notice should identify the specific geographic
area within an AQCR where the problem exists.
e. If the non-attainment area is an AQMA, the Federal Register Notice
should inform the State that the plan revision for attainment and main-
tenance should be developed and submitted in accordance with procedures
set forth in Subparts A, B, and D and other EPA guidance, and should
provide a schedule under which the full attainment and maintenance plan
must be submitted.*
f. The other portions of the SIP which may need to be revised as a conse-
quence of the control strategy revision. These may include portions
required under the following sections of 40 CFR 51:
(i) Section 51.11 Legal Authority—especially if transportation
or land use controls are deemed necessary.
(ii) Section 51.15 Compliance Schedules--must be provided if new
control regulations are adopted.
(iii) Section 51.17 Air Quality Surveillance--if the Region has a
substantial air quality problem, more ambient sampling may be required
to define the extent of the problem and monitor progress.
*The final 40 CFR 51 regulations for maintenance plan for areas that need
to submit a plan to attain national standards may specify a constraint
on the length of this schedule (such as July, "1978).
28
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(iv) Section 51.21 Intergovernmental Cooperation—portions may
need to be revised if the State delegates new responsibility to
other State or local agencies to carry out portions of the plan.
(v) Section 51.20 Resources—new control regulations may require
additional resources for enforcement purposes. Such information
should be reported with the plan revision.
(vi) Section 51.10 General Requirements—the control regulations
submitted as part of the plan revision will probably indicate the
need for a change in the date of attainment of the national
standards. The notice should specify that the revision must provide
for the attainment of the primary standards "as expeditiously as
practicable." Until the Clean Air Act is amended to provide
for extensions of the deadlines, the mid-77 attainment date is
still technically the "no later than" cut-off point of the Act for most
areas. [A one-year deferral mechanism (i.e., Section 110(f)) exists for
source specific extension cases. However, OE advises that use of such a
mechanism, because of the requirements of adjudicatory hearings, can be
time consuming and should probably be minimized.]
For those few areas with pre-1977 attainment dates in which it
is reasonably certain that a control strategy can be developed which
could attain the standards by mid-1977, the state should be required
to submit revisions which will attain the standards "as expeditiously
as practicable," but no later than mid-1977. The state should be told
that it will be necessary to apply formally for a deadline extension
of the original attainment date (e.g., May, 1975) pursuant to Section
29
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110(e) and 40 CFR 51.30. If these requirements are otherwise met, an
extension can be granted if the revised plan requires significantly
more stringent controls than contained within the original SIP.
For most areas it will be impossible to identify an appropriate
attainment date in the notice because, although the analysis supporting
the notice must identify the nature and extent of the problem, an appro-
priate attainment date will not be identifiable until the control strategy
is developed. For these cases, the notice should require the State to
identify a new attainment date, which must be "as expeditiously as practi-
cable", and submit it for approval with the plan revision. (It should
be noted that this is an interim policy until the Act is amended to
provide new attainment deadlines and/or extension procedures.)
g. The notice should specify the date for submission of the revision.
Section 51.6(b), Revision, states that "the plan shall be revised within
60 days following notification by the Administrator, or by such later date
prescribed by the Administrator after consultation with the State." Since
a control strategy will need to be developed, compliance schedules deter-
mined and negotiated with regulations subjected to a public hearing and
adoption, it appears that six months or more may be needed to revise the
control strategy portion of the plan.
The Agency has established firm end dates for the submittal of plan
revisions by States to attain national standards. Plan revisions, containing
emission linitations, shall be submitted by July 1, 1977. In cases where
additional measures are necessary (e.g., land use and transportation controls)
30
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such measures may be submitted no later than July 1, 1978. It should be
noted that these are "no-later-than" dates and that plan revisions should
be submitted as expeditiously as practicable. (NOTE: No firm end dates
exist for areas that need only maintenance plans. The schedule for the
development and submittal of such plans is to be established by the Regional
Administrators.)
h. The Federal Register Notice should also request that the Governor of
the State advise EPA within 60 days of its intention to comply with
the request for a plan revision and to set forth a timetable for starting
and completing each major element of the work to be done in developing the
revision. Major milestones may include (a) the development of the control
strategy, (b) preparing draft legislative amendments, where necessary,
(c) public hearing dates, and (d) submission of plan to EPA. The State
should also advise the Regional Offices of the agencies responsible for the
development of the plan revision and where appropriate, an identification
of the responsibilities of each agency when multi-agencies are involved with
the development of the plan revisions. The notice should clearly state
that EPA will begin to take action to disapprove the pertinent sections of
the SIP and/or to develop, propose and promulgate EPA regulations, if the
State does not provide an indication of its intent to comply with the revi-
sion notice within the stated time period.
i. The Federal Register Notice should declare that all existing elements
in the plan remain in effect (and are fully enforceable) until the revision
is submitted by the State and approved by EPA or EPA promulgates any needed
revision. In other words, there should always be a plan in effect. Also,
since only the specific regulations that are added or changed by a plan
revision are subject to a Section 307 challenge, it would be prudent
31
-------
in those cases where possible, not to change any currently approved
regulations but rather add new regulations to the SIP. However, where
the alternative of revising an existing regulation is clearly superior
to adding a new regulation, fear of litigation should not deter a
revision of the existing regulation.
j. The Notice should point out that the plan revision must be submitted
in accordance with the provisions of 40 CFR 51.4, Public Hearings, and
51.6, Revisions and the other requirements of Part 51. In addition, the
Federal Register Notice should contain a justification indicating why
the finding of a plan deficiency is not subject to public comnent at this
time. OGC believes that the Agency's technical determination of the
necessity for a plan revision does not need to undergo rulemaking procedures
at the time of calling for a plan revision. The public will have ample
opportunity to comment on the action when the plan revision has been sub-
mitted by the State (or when EPA proposes its own remedial measures). As
with other plan submittals, the public must be advised of any plan revision
submission and be allowed to comment on the action. An example Federal
Register notice is provided in Appendix A.
2. Other Federal Register Actions
In addition to the Federal Register Notice discussed above, other
Federal Register actions need to be taken. These actions depend upon the
State's response in relation to the plan revision requirement.
In those cases where the State submits a letter of intent, followed
by a plan revision, no action should be taken to disapprove the original
SIP prior to the review of the SIP revision. After the State submits
its revisions and EPA reviews them, concurrent actions can be taken to
32
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disapprove particular parts of the original SIP and approve the new or
revised parts. Such procedure would minimize the paper work involved
in the preparation of the Federal Register and briefing memo documents,
and avoid discontinuities in the regulatory process.
In those cases where a negative response or where no letter of
intent is received from the State in relation to the request to modify
the SIP, or where no plan revision is submitted as required, the Agency
shall take action in a timely fashion to simultaneously propose disapproval
of the pertinent portions of the SIP and propose EPA substitute and/or
additional regulations. Such disapproval and regulatory actions should
seek to minimize disruptions in implementing acceptable regulations, and
be taken in such a manner so_ that a_ plar^ remains in_ effect at_ aj 1 time.
Agency procedures for preparation of Federal Register actions
are provided in OAQPS Guidelines Series Document No. 1.2-005A
(revised).
3. Letter to the Governor
It is recommended that a letter be sent to the Governor(s) of the
affected State(s) of the necessary action prior to publication in the
Fe de ra 1 Register. Since some explanation of the reason for the plan
revision is in order, it may be appropriate to attach a draft copy of
the Federal Register notice.
The State Agency should also be advised of the pending Federal Register
action. However, since the State should already be intimately aware of
the content of the call for plan revision from ongoing discussions with
them on the attainment problems, the letter to advise them of the
publication of the notice in the Federal Register is more of a courtesy.
33
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C. PLAN SUBMITTAl
Once the plan revision is submitted by the State, the Agency pro-
cedures outlined in the OAQPS Guideline No. 1.2-005A govern the review
and approval/disapproval process.
34
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V. Overview of Necessary Actions in Relation to Substantially
Inadequate SIP's
The purpose of this Chapter is to provide an overview of the
necessary actions in relation to identifying substantially inadequate
SIP's and calling for Plan Revisions. While this guideline thus far
has discussed procedures to be followed for all areas of the nation
to determine if a SIP is substantially inadequate, certain follow-up
actions are different, depending upon whether an area has been designated
as an AQMA (Air Quality Maintenance Area) or as non-AQMA. Consequently,
two slightly different flow charts that sequentially identify the necessary
actions are provided for AQMA's (Table 2) and non-AQMA's (Table 3). These
minor differences can be seen in Steps 1 and 4 and result from specific
activities and requirements for AQMA areas that do not exist for non-AQMA
areas.
35
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TABLE 2
ACTION STEPS FOR AQMA AREAS WKLRE SIP'S ARE SUBSTANTIALLY IMADEQUATE. TO
ATTAIN NMQS
STEP 1. RO's, with State and local agency assistance as appropriate, determine
those areas of the nation for each criteria pollutant where the SIP is
substantially inadequate to attain NAAQS. Determination by 7/76.
(RO's may wish to use as input the AQMA analysis proposed (in the main-
tenance regulations) to be submitted by the State to EPA by April, 1976.)
STEP 2. RO discusses findings of analysis with State and local agencies and
determines which control regulations should be modified or added by 7/76.
STEP 3. RO advises Governor of State by letter of necessary plan revision by 7/76.
STEP 4. RO publishes a FederaJ Register Notice (without proposal) to publicly
announce need for plan revision, by 7/76. Proposal indicates among
other things that all emission limitations (as needed) which it is
reasonable to anticipate will be achievable within a reasonable
period of time must be submitted by 7/77, other measures (e.g., land
use and transportation measures) by 7/78 and a requirement that the
State notify EPA within 60 days of its intent to propose and submit
plan revision. Further, RO should advise State that plan revision should
be developed in relation to Subpart D and other EPA guidance for mainten-
ance area. Also, since the final 40 CFR 51 regulations for maintenance
plans may specify a constraint (such as July, 1978) for subn;ittal of
maintenance plans in non-attainment AQ'IA's, this should be noted in the
Federal
STEP 5. State submits to RO within 60 days letter of intent with schedule for
completion of major plan items to develop plan revision. If no response,
RO proposes plan revision to attain and maintain fiAAQS in a timely
fashion.
STEP 6. State submits, by 7/77, plan revision with adopted regulations-
STEP 7. RO notifies public of 7/77 plan submittal in the Federal Register, seeks
coninents and proposes to approve or disapprove 7/77 plan submittal.
STEP 8. RO approves 7/77 plan submittal, or disapproves and proposes EPA substi-
tute regulations.
STEP 9. Where necessary, State submits by 7/78 othsr control measures needed
to attain and maintain national standards, such as land use and trans-
portation control measures.
STEP 10. RO notifies public of 7/78 plan submittal in the Federal Register, seeks
comments and proposes to approve or disapprove 7//8 plan submittal.
STEP 11. RO approves 7/78 plan submittal or disapproves ana proposes EPA substi-
tute measures.
NOTE: (1) Dates do not apply to those AQMA's where only a maintenance plan
is required. In such cases, the Regional Administrator can establish
any date for submittal of a plan that considers maintenance only
(i.e., not attainment and maintenance).
(2) All dates are latest dates acceptable for this sequence of events.
(3) Step 1, 2, 3 and 4 all have end dates of July 1976. It should be
noted that such steps are sequential and require time between steps for
implementation. It is recommended that these steps be spread out from
April to July, 1976, however Regional Offices have the latitude to
establish interim dates as they consider appropriate. Only the July,
1976, notice to the States of a need for a plan revision is a firm
Agency date.
36
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TABLE 3
ACTION STEPS FOR NON-AQMA AREAS WHERE SIP'S ARE SUBSTANTIALLY
INADEQUATE^ TO ATTAIN NAAQS
STEP 1. RO's, with State and local agency assistance as appropriate,
determine those areas of the nation for each criteria pollutant
where the SIP is substantially inadequate to attain NAAQS.
Determination by 7/76.
STEP 2. RO discusses findings of analysis with State and local agencies
and determines which control regulations should be modified
or added by 7/76.
STEP 3, RO advises Governor of State by letter of necessary plan "
revision by 7/76.
STEP 4. RO publishes a Federal Register Notice (without proposal) to
puolicly announce need for plan revision, by 7/76. Proposal
indicates among other things that all emission limitations (as
needed) which it is reasonable to anticipate will be achievable '
within a reasonable period of time must be submitted by 7/77,
other measures (e.g., land use and transportation measures)
by 7/78 and a requirement that the State notify EPA within 60
days of its intent to propose and submit plan revision.
STEP 5. State submits to RO within 60 days letter of intent to
develop plan revision with schedule for completion of
major plan items to develop plan revision. If no
response, RO proposes plan revision to attain and main-
tain NAAQS'in a timely fashion.
STEP 6. State submits, by 7/77, plan revision with adopted regulations
up to RACT (as needed).
STEP 7. RO notifies public of 7/77 plan submittal in the Eedej-al Register,
seeks comments and proposes to approve or disapprove 7/77 plan
submittal.
STEP 8. RO approves 7/77 plan submittal, or disapproves and proposes
EPA substitute regulations.
STEP 9. Where necessary, State submits by 7/78 other control measures
needed to attain and maintain national standards.
STEP 10. RO notifies public of 7/78 plan submittal in the Federal Register.
seeks comments and proposes to approve or disapprove 7/78 plan
submittal.
STEP 11. RO approves 7/78 plan submittal or disapproves and oroposes EPA
substitute measures.
NOTE:
(1) All dates are latest dates acceptable for this sequence of events.
(2) Step 1, 2, 3 and 4 all have end dates of ,lnl« 1976. H should be
noted that such steps are sequential and require time between steps for
implementation. It is recommended that these steps be spread out from
April to July, 1976, however Regional Offices have the latitude to
establish interim dates as they consider appropriate. Only the July,
1976, notice to the States of a need for a plan revision is a firm v
Agency date.
37
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APPENDIX A
(Example Federal Register Notice)
NON-AQMA AREA
ENVIRONMENTAL PROTECTION AGENCY
APPROVAL OF STATE IMPLEMENTATION PLANS
Notice of Required Revision to Part of the State Implementation Plan for
the Metropolitan Smogtown Intrastate Air Quality Control Region
On May 31, 1972 (37 F.R. 10842), pursuant to Section 110 of the Clean
Air Act, and 40 CFR Part 51, the Administrator approved the control stra-
tegy for the attainment of national primary and secondary standards for
suspended particulate matter in the Metropolitan Smogtown Intrastate
Region. The plan was designed to attain these national standards by date,
(such as June 1975).
On the basis of recent air qual-ity data submitted by the State in
fulfillment of the requirements of Section 51.7 (Reports), and from the
evaluation of various compliance actions taken by the State to implement
the adopted particulate emission control regulations of the applicable
plan, it is the technical judgement of the Regional Administrator for
Region III, that the presently approved control strategy portion of the
plan for particulate matter (i.e., pursuant to 40CFR Section 51.13) is
inadequate to attain the national particulate matter standards. There-
fore it is necessary to add additional control measures- to the plan or
revise one or more existing regulations for control of particulate matter.
Specifically, this finding is based upon a detailed diffusion modeling
analysis of the urban-industrialized section of Southeast Smogtown, (State)
This analysis, which has been summarized in a technical report entitled
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"The Suspended Participate Problem in Smogtown" is available for inspec-
tion and copying at the Environmental Protection Agency, Region III,
Curtis Building, 6th and Walnut Streets, Philadelphia, PA 19106, and the
Public Information Reference Unit, Room 2922 (EPA Library), 401 M St., S.W.,
Washington, D.C. 20460. Copies of this technical report have been pro-
vided to the appropriate State and local air pollution control agencies
within the (State).
The mathematical diffusion modelling analysis, summarized in the
report, indicates that two sources contribute significant particulate
matter emissions to the atmosphere in southeast Smogtown. Emissions from
these sources, which include an uncontrolled cement plant and a moderately
controlled integrated steel mill, are such that national particulate
matter standards are predicted to be violated beyond the scheduled date
of attainment of the national standards (i.e., July 1975). The
report also identifies that the intermittent open burning at various dumps
and small uncontrolled incinerators contribute to more localized excursions
above the national standards. Based upon this analysis, the Regional Ad-
ministrator, Region III, has determined that a substantial (in the range of
30%) reduction of 1974 annual particulate matter emissions from these
plants or other sources will be needed to provide for the attainment of the
standards. Further, more vigorous enforcement of currently adopted
regulations for controlling open burning and incinerators must be under-
taken by the appropriate air pollution control agency. Alternatively,
other equivalent improvements in the particulate control strategy may be
employed, as determined by the State and approved by EPA.
Because of this identified deficiency, the Regional Administrator
finds that a revision to parts of the control strategy for particulate
A-2
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matter in the applicable plan is needed. This Federal Register; Notice
is intended to officially advise the (State) of this requirement.
Accordingly, the State shall prepare and submit, by July 1, 1977, a
plan revision containing adopted emission limiting regulations, as
needed, which it is reasonable to anticipate will be achievable within
a reasonable period of time to provide for the attainment and mainten-
ance of the national primary particulate matter standards. If additional
control measures (e.g., land use and transportation measures) are
needed, such measures may be submitted no later than July, 1978. The
plan revision should identify the nature and sources of emissions
within the Southeast portion of Smogtown and demonstrate how the adopted
regulations will provide for the attainment and maintenance of the
national standards^. The plan should include a demonstration that
emission increases that will result from projected growth of population,
industrial activity, etc., will not cause the national standard to be
violated. Compliance schedules for any source affected by any new or
revised regulation must be submitted in accordance with the requirements ;
of 40 CFR 51.15 (Compliance Schedules). The plan revision should also i
indicate any additional resources needed to implement the control plan
beyond tliose already provided for in the plan, along with the State's !
i
commitment to provide additional manpower and money to implement the con- i
trol measures. If responsibility for implementing any portion of the
plan revision is delegated to other State and/or local agencies, a l
description of the specific responsibility of each agency in implementing <
i
i
the plan shall be submitted. The plan revision shall be submitted by ;
the State in accordance with the provisions of Section 51.4, Public
i
Hearings, and Section 51.5, Submission of Plans and otherwise fulfill •
l
the requirements of Part 51.
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The State is advised that the plan revision must provide for the
attainment of primary standards as expeditiously as practicable. It is
the judgment of the Regional Administrator that adequate time exists
for the State to revise the plan so as to provide for attainment of
primary standards by mid-1977 as provided under the Clean Air Act.
If the plan revision requires substantially more restrictive emission
controls than are presently included in the approved plan, and if
the requirements of 40 CFR 51.30 are met, then an extension to mid-
1977 can be approved by the Agency for the attainment of national primary
particulate matter standards. Such an extension should be formally
requested by the Governor when submitting the plan revision. The State
is further advised that additional time can be provided for the attain-
ment of secondary standards, so long as such standards are attained within
a "reasonable time". The revised plan shall indicate the date the
national standards will be attained.
The Governor shall submit, within 60 days, a letter of intent to
the Regional Administrator, EPA, Region III which identifies the various
action steps (along with target dates for completion) which the State
will take to develop the plan revision in accordance with the require-
ments set forth in this notice. The S, ite must also identify the agencies
that have been given responsibility to prepare the plan revision. Failure
by the State to submit a letter of intent within the allotted 60 days
will be considered by EPA as an indication that no plan revision will be
forthcoming from the State. In this case, EPA will begin to develop for
promulgation a federal plan to attain and maintain national standards.
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All of the applicable plan remains in effect until the plan revision
is submitted by the State to EPA and is approved by EPA or until EPA
promulgates substitute (or additional) regulations.
This notice is not subject to rulemaking procedures. The need for a plan
revision is based upon a technical finding of the Regional Administrator
which clearly shows that the control strategy for particulate matter in
the Metropolitan Smogtown Intrastate Region is inadequate and needs to be
revised. Authority for such action is provided in Sections 110(a)(2)(H)
and 110(c) of the Clean Air Act, 1970. Ample opportunity for public comment
on the Regional Administrator's determination will be provided. If the
State develops its own revisions and submits them to EPA, public hearings
will be required at the State level and EPA will provide opportunity for
written comments prior to taking action on the submission; if EPA must
propose and promulgate its own regulations, EPA will provide opportunity
for written comments and, if the State held no hearing on the revisions,
will provide opportunity for a public hearing. Authority: Section
110(a)(2)(H) of the Clean Air Act, as amended, 42 U.S.C. 1857c-5(a)(2)(H)
and Section 110(c) of the Clean Air Act, as amended, 42 U.S.C. 1857c-5(c).
Date
Regional Administrator
Environmental Protection Agency
A-5
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APPENDIX B. GUIDELINES ON AMBIENT TREND MONITORING
1. General Guidelines for Regional Office Monitoring Programs 1.2-007
PURPOSE: General summary of existing ambient trend moni-
toring guidelines
2. Guidelines for Interpretation of Air Quality Standards 1.2-008*
PURPOSE: Answer questions on how NAAQS and air quality is
related
3. Guidelines for Network Design and Instrument Siting 1.2-012*
PURPOSE: Network design and instrument siting criteria
4. Procedures for Flow and Auditing of Air Quality Data 1.2-013*
PURPOSE: Steps to insure valid data
5. Guidelines for Evaluation of Air Quality Trends 1.2-014*
PURPOSE: Trend evaluation
6. Guidelines for the Evaluation of Air Quality Data 1.2-015*
PURPOSE: Evaluation methodology
7. A Description of Analytical Techniques and Associated SAROAD 1.2-017
Method Codes Used in Storing Data in NADB
PURPOSE: Decoding of method codes used in NADB
8. Designation of Criteria Pollution Analytical Methods as 1.2-018*
Acceptable/Not Acceptable for Purposes of Data Analysis
PURPOSE: Acceptability of data and instruments
9. Air Quality Monitoring Site Description Guidelines 1.2-019*
PURPOSE: Information on Monitoring Sites
*Also included in Volumn 11, Air Quality Maintenance Guidelines
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APPENDIX C
ENVIRONMENTAL
PROTECTION TRANSMITTAL
AGENCY
Addressee
1270.5
October 15, 1973
DELEGATIONS OF AUTHORITY - AIR AND WATER PROGRAMS
MATERIAL TRANSMITTED:
EPA Order No. 1270.5 - Delegation of Authority to Request States to
Revise State Implementation Plans.
MATERIAL SUPERSEDED:
None.
\
FILING INSTRUCTIONS:
FtJe the attached material in numerical order in a three-ring binder
established for the EPA Directives System.
Howard M. Messner
Deputy Assistant Administrator
for Administration
Dist: Directives Distribution
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C-2
ENVIRONMENTAL
PROTECTION ORDER
AGENCY
1270.5
October 15, 1973
DELEGATIONS OF AUTHORITY - AIR AND WATER PROGRAMS
DELEGATION OF AUTHORITY TO REQUEST STATES TO
REVISE STATE IMPLEMENTATION PLANS
1. PURPOSE. This Order delegates to the Regional Administrators the
authority to request States to revise State Implementation Plans under
Section 110(a)(2)(H)(ii) of the Clean Air Act.
2. BACKGROUND. Section 110(a) (2) (II) (ii) of the Clean Air Act provides ••
for the revision of State Implementation Plans (SIF's) "whenever the
Administrator finds on the basis of information available to him that the
plan is substantially inadequate to achieve the national ambient air
quality primary or secondary standard which it implements." In view of
the emphasis on utilizing regional offices in supervising the SIP's, a
delegation of authority to the Regional Administrators to request the
revisions is in order.
3. DELEGATION. The Regional Administrators are delegated authority to
perform the responsibilities indicated above within their respective
regions.
A. LIMITATIONS.
a. Revisions will be requested only when such revisions are clearly
necessary.
b. Where the requested revision would affect emission control
regulations significantly, or the enforcement thereof, Regional Admin-
istrators should obtain the concurrence of the Assistant: Administrator
for Air and Water Programs and the Assistant Administrator for Enforce-
ment and General Counsel.
c. Where the requested revision would have significant national
policy implications or would establish a significant precedent, the
concurrence of the aforesaid Assistant Administrators is required.
Dist: Directives Distribution Initiated by: AF
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C-3
ORDER
1270.5
October 15, 1973
d. Insofar as other revisions are concerned, Regionai Administrators
should simply notify the two Assistant Administrators of requests made.
e. This authority may not be redele
RdpseB.1 E. Train
Administrator
&
PAS 4
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