## SEP201999
\..0**-I~:**

- U) r.} 

### MEMORANDUM r;"". 0 " .'. (""") I 

## 'D -;-'1 SUBJECT: State Implementation Plans: Policy Regarding**E!<c,es~** i 

### Emissions DuringMalfunctions, Startup, and**Shrrrdo~** I

# ~ I 4.-......::= j. 

### FROM: Steven'A. Herma 

## 11

# i**~:**

# .Cf.1 ,

### j~istant Admi'

### ,~ for Enforcement and

### CO~li~C~ &Assurance

.

Robert Perciasepe Assistant Administrator for Air and Radiation Regional Administrators, Regions I - X

EPA's policy for state implementation plans (SIPs) regarding excess emissions during malfunctiorts, startup, shutdown, and maintenance is contained inmemorartda from Kathleen Bennett, formerly Assistant Administrator f6r Air, Noise and Radiation 

## I dated September 28, 1982 and FebruJry 15, 1983. Arecent revie"( of.SIPs'suggests that several contJinprovisions that appear to• be inconsistent with this policy,

### ~ither because they were ' inadvertently approved after EPA

### i~sued the.1982-1983 guidance or because they were part of the**~IP** 

### at that time and have never. been

### remo~ed. In order to addressIthese provipions in a consistent manner, today we are reaffirming and supplementing the**1982~83** 

### policy. In so doing, we aJe taking this opportunity to clarify several issues of interpretation that have arisen since

### I that time. The attached updated p6licy will clarify the types of excess emissions provisions states.lmay incorporate into SIPs sot 

### that they can in turn provide greater certainty to the regulated conununity.

. I ' . I 

### As EPA stated in its 1982,memorandum, because excess emissions might aggravate air quality so as to prevent attainment or interfere with maintenance of the ambient air quality 

## .1 standards. EPA views all excess emissions as violations of the applicabie emission**limitation.N~vertheless,** 

### EPA recognizes ----".=;.".



### - 2 -
that imposition of a penalty for sudden and unavoidable malftinctions cauied by circumstances entirely beyond the control of"the own'er'or operator may not'be·a'ppropriate. Accordingly, a' state or EPA can exercise its "enforce!!lent,discretion" to refrain from taking an enforcement actionin these,circumstances.
The main question of interpretation that has arisen regarding the old policy is whether a state may go beyond this "enforcement discretion" approach and include in its SIP a provision that would, in.the context of an enforcement action for exces's emissions,'-:excuse a sourc'e from penalties if th,e source can demonstrate that it meets certain objective criteria (an "affirmative defense"). This policy clarifies that itates have 'the discretion toprovide'such a defense to actions for.penalties

brought for excess emissions that**a~ise** during certain malfunction, startup, and shutdown episodes,

, In the coht;'ext of malfunctions" EPA recognizes that even eqUipment that is properly designed andmaintained can sometimes fail. At the same time, EPA has a fundamental responsibility under the Clean Air Act to ensure that SIPs provide for attainment and maintenance of'the national ambient air quality ,standards ("NAAQS")and protection of PSD increments. Thus, EPA cannot approve an affirmative defense provision.that would undermine the fundamental requirement of attainment and maintenance of the NAAQS, or any other requirement of the Clean Air Act, See sections 110(a) and (1) of the Clean Air Act, 42 U.S.C.S 7410(a) and (1).' Accordingly, an acceptable affirmative,defense provision,may only**appl~** to actions for penalties, out not to actions for injunctive relief. This restriction insures that both state and federal authorities remaTn able to'protect air'quality standards and PSD increments. Furthermore,'this approach is appropriate only when the respective,contributions of individual sources to pollutant concentrations in ambient'**ai~·**are such that.no single source or small-group'of'sources has the potential to cahse anexceedance of the NAAQS',or PSD increments.' Where a single source or small

'Pursuant to Section 110(1), EPA may not approve a SI'P revision if "the'icevisionwould interfere with any applicable' requirement concerning attainment and reasonable further progress, or any other applicable requirement of this chapter." See also CA1C§ 193, 42 U.B:C. § 7515, and the definitions of "emis'si'on"l'imitation" and "emission standard" contained in CAA § 302(k), 42·

### d.s.c. § 7602(k).
" In the case'of leadand sulfur dioxide, attainment problems usually are caused by one or a few sources and anI .

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### group of sources has the potential to cause an exceedance of the NAAQS or PSD increments, EPA believes an affirmative defense !**-apptba~h** 

### will not be**adequat~** 

### to**p~otect** 

### public health and the environment, and the only**appropri~te** 

### means of dealing with excess.emissions during malfunctiob,**s~artup,** 

### and shutdown episodes is through an enforcement I

### discretion approach.)
EPA is also taking this opportunity to clarify that it does not intend to**approv~** 

### SIP**revision~** 

### that would recognize a state director's decision tobar EPA's**o~** 

### citizens' ability to enforce

### ap~iicable requirements. Such an

### ~pproach would be inconsistent with the regulatory scheme**establi~hed** 

### in Title I of the Clean 

### i Air Act. EPA is also adding**conte~poraneous** 

### record keeping and: notification criteria to make its

### ~olicy regarding these types of events consisteht with its enforcement approach. Finally, EPA is clarifying hol excess emissions that occur during periods of startup and

### shut~own should be addressed. In! general, because excess emissions that occur during these periods
I ' 

### are reasonably foreseeable, they should not be excused. However, EPA recognizes that, for some soud:e categories, even the best 

### ! available emissions control

### system~ might not be consistently 

# I effective during startup or shutdo*n periods. In areas where**t~e** 

### respective contributions of individual sources to pollutant I 

### concentrations in ambient air are**~uch** 

### that no single source or '. I 

### small group of sources has the potential to cause an exceedance of the NAAQS or PSD increments,**th~se** 

### technological limitations may be addressed in the underlying I

### standards themselves thLough narrowly-tailored SIP revisions that take into account the potential impacts on ambient air q0ality causedby the inclusion of these allowances. In thes.

### ins~ances, as part of its 

# I justification of the SIP revision, the state should analyze the

### i

affirmative defense is not approprtate. This situation canbe particularlyaggravatedwhere a sh0rt-term standard (e.g., where exceedances or violations are basedon a few hour period) is also inplace. Although this policy is!generally applicable for other NAAQS, enforcement discretion is.the onlyappropriate approach.

# I for dealing with excess emissions during startup, shutdown, and malfunction in a specific area where a single source or a small group of sources has the potential to cause nonattainment of a short-termNAAQS. ) In'AmericanTruckingAssociationv. EPA, 175 F. 3d 1027 (D.C. eirc., 1999), the court remartded the PM2.5 NAAQS to the EPA. The Agency has not determinedwhether this policy is appropriate for PM2.5 NAAQS.- 4 - impact of-the potential worst-'case emissions that could'occuI' during startup and**shutdown.~**

.\. ," , 

# .." • ,"-. L't' 

### •

In addition to this approach,states may address this problem through the use of enfo·rcement'discreeion or they may include a general affirmative defense provision in their SIPs for short and infrequent startup and shutdown periods along the lines outlined in theattachmept·.:· As mentioned above, however, in those areas where:'a,single source or small group of sources has the potential to cause'ame}(ceedance of the NAAQS or PSD increments, issues relating to excess emissions arising during startUp and shutdown may only.:be addresse'dthrough an enforcement discretion approij.ch·.**~**--, All Regibns should review the·SIPs for their,states in light of this clarification and take-stepsto'insure that excess emissions provisions in these SIPs are consistent with the attached guidance.,

, .: A.ttachment



# ..

",**~**-.

" ,

'States may account for such emissions by in'cluding them in their routine rule effectiveness estimates. Rule effectiveness estimates may be prepared in accordance with an EPApolicy document entitled "Guidelines for Estimating andApplying'Rule Effectiveness for Ozone/CarbonMonoxide State Implementation Plan Base Year Inventories." (EPA-452/R-92-010),November 1992. •**,~**.,'
. \

.

### Attachment

I 

### POLICY ON EXCESS EMISSIONS DURING MALFUNCTIONS, STARTUP, AND I 

### SHUTDOWN

.

,Introduct·ion ., .. ·1-

._.·e 

### This policy specifies when and·in what manner state implementation plans (SIPs) may pr6vide for defenses to viol'ations caused by·periods of exl::ess emis·sions due to malfunctions,' startup, or

### shutdow~. Generally, since SIPs must provide for attainment and

### mainten~nce of the national ambient 

## ! air quality standards and the aChibvement of PSD increments, ali periods of ex6eSS emissions

### mu~t bb considered violations.

, 

### Accordingly, any provision that allows for an automatic exemption2 

### for·

### ex~ess emissions islprohibited. However, the imposition of a penalty for excess emissions during malfunctions causedby circbmstances entirelybeyond the: control of the owner or operator

### m~y not be appropriate. States I 

### may, thereforer 

### as an exercise of their inherent enforcement discretion, choose not to penalizeja source that has produced excess emissions under such circumstances.
This policy provides an

# alte~lative approach to

# enforcemen~ discretion for areas and

### pollutant~ where the respective I 

### contributions of individual sourcek to pollutant concentrationsI 

### in ambient air are such that no sihgle source or smallgroup of: sources has the potential to causejan exceedance of the NAAQS of PSD increments. Where a single source or small group of sources has the potential to cause an**exce~dance** 

### of the NAAQS or PSD .! 

### increments, as is often the case fbr sulfur dioxide and lead,' I 

### EPA believes approaches other thanjenforcement**discret~on** 

### are**n~t** 

### appropriate. In such cases; any excess emissions may have a It 

### significant chance of causing an ekceedance or violation of the

. I, I 

### applicable standard or PSD increment. '

'The term excess emission means an air emission level which exceeds any applicable:erilission litnitation. Malfunctionmeans

# a sudden,and unavoidable breakdown of process or**controlequipmcn~_** 

### 2The term automatic exemption!means a generally applicable

# i provision in a SIP that would provide that if certain conditions existedduring a periodof excess**~missions,** 

### then those exceedances would not be considered violations. 'This policy also does not apJlY for purposes of PM2.5 NAAQS. InAmerican TruckingAssociation

# v; EPA, 175 F. 3d 1027 (D.C. Circ., 1999), the court remartded the PM2.5 NAAQS to the EPA. The Agency has not determinedwhether this policy is**~propriate** 

### for PM2.5 NAAQS.

### - 2 - Except where a single'source or small group of sources,has the potential to cause an exceedance of the NAAQS or PSD :increments,sta,tes may include in,their,SIPs affirmative ""','

defenses' for excess emissions, as long as the SIP establishes limitations consistent with those set out below. If approved into a SIP, an affirmative defense wouldbe available to sources in an enfoL'cement action**seeki~g** penalties brought by,the state, EPA, or citizens', ,Howeve,r, a determination by the state not to take an enforcement'actiQn would not'gar EPA or 'citizen action.5
In addition, in certain limited circumstances,

..{t may be' appropriate for the state to build into a source-specific,or ' source-category-specific emission standarda provision stating, that the otherwise applicable emission limitations do not apply during**narro~ly** defined startup and shutdown periods.

, ., I. '"AUTOMATIC EXEMPTIONS AND ENFORCEMENT DISCRETION
If a SIP

### con~ains a,provision

### addre~sing**exce~s** emissions; it cannot be the type that providesfor'automatic exemptions. Automatic exemptions might aggravate ambient airquality by excus:j.!1gexc;:ess,emiss,ions that cause or contribute to a ,violation of an ambie!1t'air quality standard, Additional'grounds'for disapproving,a SIP,tha):.includes the automatic exemption approach
are discuscsed'in more detaJl at 42 Fed. Reg. 58171 (November 8, 1977) 'and,42·Fed. Reg.?1372 (April 27, 1977). As a,result, EPA will not approve any**~IP Fevision~**  that provide automatic exemptions:for periods of excess,emissions. . , '. (" The best assurance that excess**emission~** will,not interfere with NAAQS attainment, maintenance, or increments is to address

### excessemissi~ns through

### e~forcement discretion. This policy;,," provides alternative means for addressing excess emissions of ' criteria pollutants. However, 'this policy does not appiy where a single source or small group of sources has the potential to cause an exceedance of the NAAQS or PSD increments. Moreover,

, , 'The'term affii:-mative defense means, in the,context of an enforcement proceeding, a response or defense put forward by a defendant,regarding which the defendant has the**bu~den** of proof, and the merits of,which are,independently and objectively' evaluated in a judicial or administrative proceeding,

• - .• • • i. 5Because all periods of excess emissions are violations and because affirmative**de~ense** provisions may not apply in actions for injunctive relief, under no circumstances wouldEPA consider periods of excess emissions, even if coveredby an affirmative defense, to be."**fed~rally** permi.tted,releases" under EPCRA or ' CERCLA,t

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### nothing in this guidance should be construed as requiring states to include affirmative defense provisions in their SIPs. 

# - " " - -"" '. I'"-, ,. II. AFFIRMATIVE DEFENSES FOR MALFUNCTIONS
EPA can approve a SIP revisiol that creates an affirmative defense to claims for penalties in!enforcement actions regarding excess emissions caused by malfunctions as long as the defense 

### I does not apply to SIP provisions that derive from federally I 

### promulgated performance standards 6r emission limits, such as new source performance standards (NSPS) and national emissions 

# I standards for hazardous air pollutants (NESHAPS).' In addition, affirmative defenses are not appropriate for areas and pollutants where a single source or small group of sources has the**potenti~l** 

### •to cause an exceedance of ,the NAAQS or PSD increments. I



### Furthermore, affirmative defenses to claims for injunctive reliJf are not allowed. To be approved,**~n** 

### affirmative defense ! provision must provide that the defendant has the burden of proof of demonstrating that:

### ~ 1. The excess emissions were causedby a sudden, unavoidable breakdown of technology, -beyond the control of the owner or operator;

, 

### 2. The excess emissions (a) did not stem from any activit1 or event that could have been foreseen and avoided, or planned 

# i for, and (b) could not have been**a~oided** 

### by better operation and[ maintenance practices;
I 

### 3. To the maximum extent pratticable the air pollution control equipment or processe5**wer~** 

### maintained and operated in


### , manner consistent with good practice for minimizing emissions;
4. Repairs were made in an expeditious fashion when the operator knew or should have known that applicable eciission limitations were being exceeded. Off-shift labor and overtime must have been utilized, to the extent practicable, to ensure that such repairs were made as expeditiously as practicable;

,

, 

### . 5. The amount and duration of the excess emissions (including any bypass) were minimized to the maximum extent practicable during periods of such1emissions; , 

# I I a

'To the extent a state,includes NSPS orNESHAPS in its SIP, the standards should not deviate from those that were federally promulgated. Because EPA set**thes~** 

### standards taking into account technological limitations, additiorta1 exemptions would be inappropriate. I

### - 4 -
6. "A:ll'possible steps were taken to minimize the impact.of the excess emissions on ambient air quality; .'

..**~** ,: 

### 7. All emission monitoring**syste~s** 

### were kept in operation if at all possible;
8. The owner or.operator's actions in response to the excess**emi~sionswere** 

### documented by properly signed,· , contemporaneous operating logs, or other relevant evidence;
9.**~heexcess** 

### emissions were not part of a**~ecurring** 

### pattern ihdicativeof inadequate'design! operation, or maintenance; and
10. The owner or operator properly and promptly notified the appropriate regulatory authority.
EPA interprets these criteria narrowly. Only those malfunctions that are sudden, unavoidable, and**unpredict~ble** 

### in nature qualify for the defense. For example, a single instance of a burst pipe that meets the above criteriamay qualify under an affirmative·defense. The defense would not be available, however, if the facility had a history of similar failures because of improper design, improper maintenance, or poor operating practices. Furthermore,.a source must have taken all available measures to compensate for and.resolve the malfunction. If a**~acility** 

### has a baghousefire that leads to excess emissions, the affirmative defense would be appropriate only for the period of time necessary to modify or curtail operations to come into compliance. The ·fire should-not be used to excuse excess emissions generated during an extended period of time while the operator orders and installs new bags, and relevant SIP language must limit applicability of the affirmative defense accordingly.
III. EXCESS.EMISSIONS DURING**STA~TU?** 

### AND SHUTDOWN
In general, startup·and shutdown of process equipment.are
. part of the normal operation of a source and shouldbe accounted for in the plannin'g, design,. and implementation of vperating procedures for the**proce~s** 

### and control equipment. Accordingly, it is reasonable to expect,that careful and prudent planning,and design will eliminaEe violations of emission limitations**durin~** 

### such periods.
A. SOURCE CATEGORY SPECIFIC RULES ·FOR STARTUP AND SHUTDOWN

" 

### For some.source categories, given the types of control technologies available, there may exist short periods of . \ emissions during startup and shutdown when, despite best efforts**~egarding** 

### planning, design, and operating prcicidures, the

.

# C .'.i ':"':::.,' ,r

• ,( - 5 - '

th ' 1'bl .' l" 

### I , b o erW1se app 1ca e em1SS10n 1m1tat10n cannot e met. Accordingly, except in the case**wh~re'a** single source or,small group of sources has the potential

# I to"cause"'an exce'edan:ce''ofth'e NAAQS or PSD increments, it may be:appzopriate, in consultation with EPA, to create narrowly-tailored**~IP** revisions that take these technological limitations into account and state that the otherwise applicable emissions limitations do not apply during narrowly defined startup and shutd6wn periods. To be approved, these revisions should meet the following requirements:

, ' 

### " I. , . 1. The'revision must be limited to specific, narrowlydefined source categories using specific control strategies (e.g., cogeneration facilities burning natural gas and using ,selective catalytic reduction);
2. Use of,the must be technically periods; control**strat~gy** for this source category infeasible during startup or shutdown



### 3. shutdown I The frequency and

## duratio~ of mode must be minimized toithe practicable; I

, operation in startup or maximum extent

4. As part of its justification of the SIP revision, the state should analyze the potential,worst-case emissions that could occur during startup and shutdown;
5. All possible steps must be taken to minimize the impact of emissions during startup and shutdown on ambient air quality)
6. At all times, the facility must be

# operat~d in a mannek consistent with good practice for minimizing emissions, and,the source must have**~sed** best efforts regarding planning, design, and operating procedures to meet tpe otherwise applicable emission limitation; and I"

I 7. The owner or operator's aCtions durin§ startupand shutdown periods must be**documente~** by properly Signed, contemporaneous operating logs,**or~** other relevant evidence.



### , , B. GENERAL AFFIRMATIVE DEFENSE PROVISIONS RELATING TO STARTUP AND SHUTDOWN
In addition to the approach oLtlined in Section IlIA) above, states may address the problem of

### ~xcess emissions occurring during startup and shutdown periodb through an enforcement discretion approach. Further, exc1ept in the case where a single source or small group of sources

### h~as the potential to cause an

# I exceedance of the NAAQS or PSD increments,,states may also adoPrt for their SIPs an affirmative**def~nse** approach. Using this

I ".- 6 - approach, all**~efiods** of**ek~eis** emissions.arising during startup and shutdownmust be treated as violations" and the·affirmative
,,···,·..·,,·····'·Oefenseiprbvision'mu·st'not'be available for claims'for injuncHve' relief, Furthermore, to be approved, such a provision must provide**that'~he·defetidant** has-the burden of proof of. demonstrating that:

. ,

.

### ,



### ... ,1.' The periods·of excess einissions·that occurred during. startup**an~;shdtdo~n·were** short and infrequent and couldnot have been prevented through careful planning and design;



### ., 2.' The excess emissions'were not part of a .recurring pattern indicative'of in'adequate.de·sign, 'operation, or maintenance; 3; 'If the excess emissions'were caused by a bypass (an intentional diversion·of control.equipment), .thenthe bypass was unavoidable to prevent loss of life, personal injury, or severe property damage;'
4. At all times,' the facility'was operated in a manner consistent with good practice for minimizing emissions; 

### 5: ,The'frequency and duration.of operation in'startup or shutdown mode**was~minimized** to the maximum extent practicable;
6. All possible steps were taken to minimize the impact of the excess emissions'on ambien·t air quality;·
7. All emission monitoring systems were kept in operation if at all possible;
·8. The owner or operator's actions during the p,eriod of· excess emissions were documented by properly signe.d, contemporaneous operating logs, or other relevant evidence; and
9. The owner, or operator properly and promptl'y notifie9 the appropriate regulatory authority.
If excess emissions occur during routine startup or shutdown periods due to a malfunction, then those instances should be treated as other malfunctions that**~re** subject to the**ma~function** provisions of this policy. (Reference Part I above)

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benneI1899a.wpdlAuguSI11,1999