Monday
January 31, 1994
 Part ill

              i:;

 Environmeanfal

 ProtectiQgji  Agency

 40 CFR Parts 9 arid 63
 List of Regulated {Substances and
 Thresholds for Accidental Release
 Prevention and  Risk Management
 Programs for Chei^Scal Accident Release
 Prevention; Final Bule and Motice
              •r.

              V
              i
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   i^478      Federal Register / Vol.  59,  No. 20 7 Monday, January
   ENVIRONMENTAL PROTECTION
   AGENCY

   40 CFR Parts 9 and 68

   P=RL-4828-6]

   List of Regulated Substances and
   Thresholds for Accidental Release
   Prevention; Requirements for Petitions
   Under Section 112(r) of the Clean Air
   Act as Amended

   AGENCY: Environmental Protection
   Agency (EPA).
   ACTION; Final rule. 	

  SUMMARY: The Environmental Protection
  Agency (EPA) is promulgating the list of
  regulated substances and thresholds
  required under section H2(r) of the
  Clean Air Act as amended. The list is
  composed of three categories: A list of
  77 toxic substances, a list of 63
  flammable substances, and explosive
  substances with, a mass explosion
  hazard as listed by the United States
  Department of Transportation (DOT).
  Threshold quantities are established for
  toxic substances ranging from 500 to
  20,000 pounds. For all listed flammable
  substances the threshold quantity is
  established at 10,000 pounds. For
  explosive substances the threshold
  quantity is established at 5,000 pounds.
  The list and threshold quantities will
  Identify facilities subject to chemical  '
  accident prevention regulations
  promulgated under section li2(r> of the
  Clean Air Act as amended; a proposed
  regulation for such requirements has
 been published in the Federal Register
 on October 20,1993. entitled Risk
 Management Programs for Chemical
 Accidental Release Prevention. EPA is
 also promulgating in this regulation the
 requirements for the petition process for
 additions to, or deletions from, the list
 of regulated substances. EPA is
 deferring action on a proposed
 exemption from regulation for listed
 flammable substances when used solely
 for facility consumption as fuel. For a
 document relating to the proposed
 exemption, see a supplemental notice
 published elsewhere in this issue.
 DATES: This rule is effective March 2
 1994,
 ADDRESSES: Docket: Supporting
 information used In developing both the
 proposed and the final rule is contained
 in Docket No. A-91-74. The docket is
 available for public inspection and
 copying from 8 a.m. to 4 p.m., Monday
 through Friday, at the EPA'S Air Docket
 Section. Waterside Mall, room M 1500,
 U.S. Environmental Protection Agency,
401M Street, SW.( Washington, DC
   20460. A reasonable fee may be charged
   for copying.
   FOR FURTHER INFORMATION CONTACT:
   Vanessa Rodriguez, Chemical Engineer;
   (2'02) 260-7913, Chemical Emergency
   Preparedness and Prevention Office,
   Mailcode 5101, U.S. Environmental
   Protection Agency, 401 M Street, SW.,
   Washington, DC 20460, or the  ,
   Emergency Planning and Community '
   Right-to-Know Hot Line at 1-800-535-
   0202.

   SUPPLEMENTARY INFORMATION: The
   information presented in this preamble
   is organized as follows:
  I. Introduction
    A. Statutory Authority
    B. Background  ,
  II. Clean Air Act Amendments of 1990
 ,   A. Prevention of Accidental Releases
    B. List of Substances and Thresholds; , •".
     Petitions for Additions and Deletions
   .1. Legislative Requirements     :
    2. Summary of Proposed Rule
  IH. Public Participation  -
  IV. Discussion of Comments and Major
     Regulatory Changes
    A. List of Substances and Threshold
     Quantities       -   .  .'.,'•   '-.-...
    1. Toxic Substances                ,
    a. Listing Criteria    '
    b. Specific Substances
    c. Other List Options Considered
    d. Threshold Quantities .     '        •
   e. Other Threshold Quantity Options
     Considered
   2. Flammable Substances
   3. Explosives •  .     '                .
   B. Threshold Determination       '     ,.
   1. Basis for Threshold Determination
   2. Mixture Exemption
   a. Toxic Substances
   b. Flammable Substances
   c. Explosive Substances
   3. Other Threshold Exemptions
   C. Petition Process  '
   D. Definitions  .
   E. Exemptions
   F. Scope
 V. Summary of Provisions of the Final Rule
 VI. Required Analyses
   A. E.0.12866
   B. Regulatory Flexibility Act    .
   C. Paperwork Reduction Act           .
   D. Display of OMB Control Numbers

 I. Introduction

 A. Statutory Authority

   rhis final rule is being issued under
 sections 112(r) and 301 of the Clean Air
 Act (CAA or Act) as amended (42 U.S.C.
 ?412(r), 7601).

 B. Background

   Public awareness of the potential
 danger from accidental releases of
 hazardous chemicals has increased over
 the years.as serious chemical accidents
have^occurred around the world (e.g'.7
th'e 1974 explosion in Flixborough,
England, and the 1976 release  of dioxin
in Seveso, Italy). Public concern
   intensified following the 1984 release of
   methyl isocyanate in Bhopal, India,  '
   which killed more than 2,000 people
   living near the facility. A subsequent
 '  release from a chemical facility in
   Institute, West Virginia, sent more than
   100 people to the hospital and made
   Americans aware that such accidents
   can and do happen-in.the United States...
    In response to this public concern and
   the hazards that exist, the U;S.
   Environmental Protection Agency (EPA)
   began its Chemical Emergency   ' "  -
   Preparedness Program (CEPP) in 1985,   /
   as part of the Agency's Air Toxics
.   Strategy. CEPP was a voluntary program
   to encourage state and local authorities
   to identify hazards in their areas and to
   plan for chemical emergency response
   actions. In 1986, Congress adopted
   many of the elements of CEPP in the     '
  Emergency Planning and Community
  Right-tp-Know Act of 1986 (EPCRA),
  also known as Title III of the Superfund
  Amendments and Reauthorizatibn Act
  of 1986  (SARA Title  HI). EPCRA
  requires states to establish state and
  local emergency planning groups,
  namely the State Emergency Response
  Commissions (SERCs) and the Local.
  Emergency Planning Committees :
  (LEPCs), to develop emergency response
  plans for each community. EPCRA
  requires facilities to provide information
  on the' hazardous chemicals they have
  on-site; the info'rmation collected is
  available to the public through the
 :SERC/LEPC structure. This information  •
  forms the foundation of both the   ..     ;
  emergency response plans and the
 public-industry dialogue on risks and .
 risk^reduction.
   Congress required EPA, under EPCRA
 (SARA Title III) section 305(b), to    " ., .
 conduct a review of emergency systems
 to monitor, detect, and prevent chemica
 accidents. The final.report to Congress,
. Review of Emergency Systems  (EPA,
 1988), concluded that the prevention of
 accidental releases requires an •
 integrated approach that considers
 .technologies, operations, and
 management practices. The report
 emphasized the importance of
 management commitment to safety
   In 1986, EPA established a chemical   '-
 accident prevention program to collect
 information on chemical accidents and
 work ,with other groups to increase
 knowledge of prevention practices and  '
 encourage industry to improve safety at
 facilities. Under this prbgram, EPA  .
.developed its Accidental Release :
Information Program (ARIP) to  collect
data on the causes of chemical accidents
and the steps facilities take to prevent
recurrences, EPA also'developed a
program for conducting chemical safety
audits at facilities. Through the audit

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one percent of the mixture by weight.
EPA also proposed to exempt     ;,
substances if (1) they are part of articjes.^
(2) if they are used as structural
components; (3) if they «« »«ft J" .^.
ianitorial maintenance; or (4) it they are:
found in consumer products, process
water, or in water or air from the
environrbent of municipal sources.
Activities in laboratories were also
proposed for exemption. In addition  an,
exemption was proposed for flammable
substances present at a facility to be    ;
'used solely for consumption as fuel at
the facility.    ^' .         ..."
   The Agency also proposed ^
 requirements for petitions to add or
 delete regulated substances under  .
 section 112(r). The Agency^roposed to
 establish that the burden of proof b^ on
 the petitioner to demonstrate that the
 criteria for addition and deletion are
 met. Basic administrative and
 documentation requirements for
 petitions were also included in the
 proposal.
 HI. Public Participation
   A hearing was held on the proposed
 rule in the EPA Auditorium, 401M
  Street, SW., Washington DC, on
  Tuesday, April 12,1993. The heanng
  was held to provide interested parties
  the opportunity for oral presentation of
  data, views, or arguments concerning
  the proposed rule. This hearing was
•  open to the public; a transcript of the
  public hearing is available in the docket.
  A total of 272 letters were received
 .during the public comment period on
  the proposed rule (an additional18
  were received after the close of the  _
  public comment period); copies of aH
  comment letters received are available
  for public inspection in the docket, A
  response to comments document,
  entitled Proposed Ust of Substances
   and Thresholds for Accidental Release
   Prevention: Summary and Response to
   Comments, includes a summary of
   comments received and the Agency s
   responses; the dpcument is available in
   the docket.
   IV. Discussion of Comments and Major
   Regulatory Changes              ,
     This portion of the preamble
   discusses comments on major issues
   received on the proposed list and
   thresholds rule and the principal
   regulatory changes made in the final
   rule in response to pubUc comments.
   mduded in the discussion is the
   rationale for these changes and the
   Agency action on the comments. Where
   the proposed regulation has not been
   changed in Uie final rule, the Agency
   : continues to rely on the rationale  ,
   provided in the prbposal notice,
A. Ust of Substances and Thresholds
  The list of substances and thresholds
promulgated today identifies sources
that are subject to accident prevention
regulations promulgated under section
. 112(r)(7Jof the Act. The list of
 substances is intended to focus  ..".
 accidental release prevention efforts on
 those stationary sources and substances
 that pose the most significant risks to
 the community. These risks may be  ~
 established either by the potential of the
 chemical ted cause harm (the inherent
 hazards and, physical/chemical
 properties!, known incidents (accident
 'history), or a combination thereof. EPA
 strongly emphasizes that the substances
 promulgated in today's listing are not
 the only substances that may pose a
 threat to communities upon release.
 There are large numbers of compounds
 andmixtures in commerce inthe U.S.
 thai in specific circumstances could be
  considered dangerous to human health
  or the environment; however, it would
  not be feasible io include all.such
  substances and circumstances. This list
,"•- should serve to focus prevention efforts
  and is not a list of all substances that
  could be'considered for accident
  prevention. Similarly, the threshold
  quantities established today may not
  always represent a level below which no
  hazard exists. Although stationary
  sources will be required to comply with
  the accidental release prevention
  regulations-under section 112(r)(7)(B)
  only if they have listed substances in ••;
  quantities exceeding the threshold
  quantity, it does not mean that these
  substances in smaller quantities
  representno potential hazard to the
   community in certain circumstances. In ...:
  "support of this principle Congress
   included general duty provisions under
   section 112(r)(l) of the Act.    '  -
     Several eommenters objected to the
   listing of classes of substances such as
   explosives orparticular substances such
  -as various flammable natural gases
   because these eommenters claimed that
   categorizing these chemicals as
   regulated substances would also make.
   these chemicals subject to the, general  .
   .duty clause of section 112(r)(l), and that
   without such listing these chemicals
   would be outside the scope of section
    112(r)(l). The general duty provision in
    section 112(r)(l) applies to "any   -_•' .  .
    substance listed pursuant to section
    112(r)(3) or any other extremety   ... •
    hazardous substance." The Agency
    believes .the scope of substances covered
  ,  by section 112(r)(l) isnot affected by
this nilem:aking except that by Including
a subikancie on the regulated substance •.=:•
list; die Agency unambiguously..,    ^
species that the general duty . -' -, • _. V
prpvi'sipnis apply to such chemicals. The
plainljanguage of section 112(rKl)  ","-.  ,
applies not only to the regulated        ;
.substances listed today but also to "any
.otheifextiemely hazardous substance:.'"
   In jiiscussing nearly identical
lahgiiage in the Senate's Clean Air Act  .
• Amendments bill of '1989, the         =:
Enviirpnment and Public Works ••
 Compittee expressed the intent that the
tenh]"exlTemely hazardous substance"  .-,
: wouLd include not only listed; ;   •-.'•
 subs|ano^ under the accident   ;
 previintioh'pfpvisions.and extremely  . ;
:hazardpvis substances under EPCRA
 (SAI^A Title HI) section 302 but also
 "other agents which may ormay not he
 liste|i or otherwise, identified by any
 Goviminent agency'which may as the
 result of shprt-term exposures
 assqpiated with releases to the air^cause
 death, irijury dr property damage"
  (Seriate Cpmrnit^eiB on Environment and
 Public Worksj Glean-Air Act
  Amtlndrnentspf 1989, Senate Report No,
  22&tl01st Congress, 1st Session 211
  (19ji9)L_."Senate Report"). Regardless of
  wh«thei',a substance is listed under
  tpdiiy's :rule, the general duty to identify
  and assHss hazards associated with
,,  accidental releases (as defined in
  sediion 112tr)(2)Ji to design and
  maintain afacility to prevent such   -;
  relelasesii and to miniinize,the  •
  coiiisequences of such releases that do
  'oocjur, extends to owners and operators
   of'(toy facility that may cause such
   imjaactii due to short-term exposures. As
   the[Senate makes clear, "the release of ;
   ani^substance which causes death or  .;
   serious injury because of its acute toxic
   effect of as:a result of an/explosion pr  '
   firji or which causes substantial
   pn»perliy damage by blast, fire, corrosion
   or other reaction would create a
  ^presumption that such substance is
   extreimely hazardous." Senate Repdrt at
  . 2li. No revision to the list promulgated
   today negates the applicabiuty, of the
   general duty provisions.
   1. Toxic Substances"      .   	
     "^'Listing criteria. Several eommenters
   sxiggestedthat EPA modify its listing
   criteria, largely so that EPA's list would
   bef more consistent withPSHA's list of
   Highly Hazardous Substances'for its
   Pirpcess Safety Management'Standard,'
   biit also because conimenters believed
   HPA's list includes some chemicals that
   do not pose the greatest'hazards to the
   pablio. Some eommenters suggestedvthe
   p'roposed 6.5 mm Hg vapor pressure cut"
    off w«is too low: Others suggested an,
    alileriiatiye methoi of choosing the list

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                                                                                                                      mil
4482      Federal Register / Vol.
                    ;	:	    ..
     of toxics namely the "Substance Hazard
     Index  . Several commenters also
     objected to EPA's use of accident history
     as a criterion for listing substances.
     EPA s proposed toxics list was based on
     the EHS list under.-SARA Title III. with
     additional consideration of the vapor
     pressures and accident histories for each
     substance. The proposed list included  -
     OSHA °     tances that a*8 not listed by
      Substance Hazard Index: Some
     commonters suggested replacing EPA's
     proposed listing criteria with another
     method labeled the "Substance Hazard
    Index" (SHI). The SHI is the ratio of a
    f t***ance!f VQP°r pressure to its acute
    toxidty; all substances would be ranked
    by their SHI and a cut-off would need
    to be selected to determine the
    substances to be listed. An SHI value of
    1,000 \vas suggested by commenters as
    a cut-off, but commenters did not
    provide a technical basis, or any other
    rationale, for why this cut-off was
    selected. The SHI value of 1,000 would
    derive a list of toxic substances that
    more closely approximates OSHA's
    PSM list than EPA's proposed list-
   provided that the Agency considers only
   those substances initially proposed for
   listing as toxics.
     EPA generally disagrees with the
   comments concerning the use of the SHI
   as a listing criterion. The Agency had
   considered this approach duringthe
   proposed rule development, but decided
   not to toclude it as an alternate listing
   methodology option. EPA instead
   considered toxidty and vapor pressure
   separately in identifying chemicals  for
   listing; the SHI combines these factors.
  fcPA believes that using separate toxicity
  an°.vaP°r pressure criteria is a more
  valid method of identifying chemical    ;
  candidates for listing. Both EPA's
  method and the  SHI approach consider
  properties related to the severity of
  acute heath effects (toxicity) and the
  livelihood of acddental releases of the
  substances (volatility), as required by
  Uie Act. However, as required by the
   «%£,?A'S Wroacb- *s based on the  list
  of EHSs as a starting point for
  identification of toxic substances (see
 f°£o! £e?°rt at  218; UstinS fact°rs used
 in EHS list are appropriate for
 ocddental release program). EPA's
 approach limits toxic chemicals to those
 Sfral £! ac"te. *<*fclty criteria for
 the EHS list and then applies a vapor
 pressure cut-off. The SHI approach does
 not include spedfic toxicity or vapor
 pressure cut-offs but instead specifies a
 cut-off value for a factor combining
 toxicity and vapor pressure. To identify
 all chemicals meeting the specific SHI
 cut-off of 1,000 as recommended by
commenters, chemicals with a much
     wider range of toxicity than those
     represented by the EHSs would have to
     be considered. Chemicals that are far
     less toxic than the EHSs would be
     potentially included, improperly    •
     characterizing the risk associated with
     them Moreover EPA does not believe
     the SHI method has been systematically
     applied to all substances for
     development of any current chemical
     list. The state of Delaware used the SHI
     approach to develop a list of substances
     lor its nsk management regulation; the
     brtl methodology was applied to
    existing lists of substances identified by
    use of toxicity criteria and not all
    substances. The Agency considers the
    bril to be more appropriate for
    determining the relative ranking of
    substances in an already established list
    I ne Agency's threshold quantity
    methodologyrfor listed toxics is similar
    on the toxicity/volatility ranking
    principle; it differs from the SHI in that
    the vapor pressure' is only part of the
    factor used to account for the potential
    dispensability of the listed substances
    For these reasons, the Agency Will not
    adopt the SHI criteria for listing toxic
    substances.
     Acute Toxicity Criteria: Commenters
   generally supported EPA's
   consideration of acute toxicify hazards
   as a basis.for listing toxic substances
   under section Il2(r). Some commenters
   however, recommended other measures
   of toxicity, such as the Emergency
   Response Planning Guidelines (ERPGs)
   developed by the American Industrial
   Hygiene Association, or data developed
  by the National Academy of Sciences
  among others. The Agency recognizes
 , the value of these other measures and
  guidelines for purposes of emergency
  preparedness and prevention activities
  However these measures are consensus
  exposure levels judged by the
  developing organizations to represent
  concentrations above which there may
  be serious irreversible health effects, or
  death, as a result of a single exposure for
 ,,a relatively short period of time. In
  addition, the methodology for most of
  these measures is still in the   ,
  developmental stages, with
 recommended guidelines or acute
 exposure levels presently available only
 tor a limited number of potentially
 hazardous substances. The Agency
 believes using acute toxicity data as
 proposed is more appropriate for the
 review and selection of hazardous •
 substances for listing under section
 112(r) because acute toxicity data
 directly reflects results of valid
 mammalian testing and thus is more
 objectively verifiable than judgmental
standards. -,
                                                            T
                                                                            ^Concerns were also expressed about
                                                                            ra^^^^^^etoxicity
                                                                                                    ci
also
also o
                                                                                      !
                                                                                      lljtl"g- Some commenters
                                                                                              ency's
                                                                                                              as
                    -sures   t
       and oral routes. EPA believes
                                                                                                             the
                                                                                          >cus'on those c
                                                                            ar0^"r7"i"ir"i°f theif inherent toxic
                                                                           .are most likely to cause immediate
                                                                            severe, irreversible health effects
                                                                            following exposures during an
                                                                            accidental release. Consequently for
                                                                            purposes of this rulemaking, the Agency
                                                                            ipnmarily interested in substances   y
                                                                            that are acutely toxic, rather than in
                                                                           Sf^f ^ C°uld Senerate a future
                                                                           health effectafter repeated long term or
                                                                          '• SST eXp,°Suref- Furthermore, acute
                                                                           toxic ty and lethality data are often
                                                                           readily available and the most
                                                                           commonly reported information
                                                                           generated ,by animal toxicity testing A
                                                                           greater number of potentially.hazardous
                                                                           substances can therefore be screened on
                                                                           the same basis using these values. For
                                                                          purposes of this rule, the listed toxic
                                                                          substances are expected to rapidly
                                                                          become airborne, thus human exposure
                                                                          by the inhalation route is of primary
                                                                          concern. The Agency believe? thatusing
                                                                          .data on oral and dermal acute lethality
                                                                          m addition to inhalation lethality- is
                                                                          appropriate for this listing    •        :
                                                                            Vapor Pressure Cut-Off: Other
                                                                          commenters suggested that EPA should
                                                                          use a higher .vapor pressure level as a     •
                                                                         ; listing criterion. EPA's vapor pressure  '
                                                                          criterion of 0.5  mm Hg was based on the  •
                                                                          properties of toluene diisocyanate  a
                                                                          substance with relatively low volatility
                                                                          which was mandated for the initial list
                                                                          by Congress. Commenters noted that
                                                                          Congress listed  toluene diisocyanate
                                                                          because it has been involved in     '    '•
                                                                          accidents, not because of its properties,  -
                                                                          and that its properties do not
                                                                          necessarily provide a valid basis for
                                                                          UPA s vapor pressure criterion. Several
                                                                          commenters suggested a vapor pressure
                                                                         of 20 mm Hg (18 mm Hg is the
                                                                         approximate vapor pressure^ water).
                                                                         but did not provide a basis for-choosing.
                                                                         this or any other vapor pressure
                                                                         criterion.      -  :            •     •-•..-
                                                                          : EPA has considered the comments '
                                                                         concerning the proposed vapor pressure
                                                                         criterion of 0.5 mm.Hg and generally
                                                                         agrees that this low vapor pressure level
                                                                         may lead to an overly conservative
                                                                         listing of chemicals that pose a    •        :
                                                                        relatively lower potential for air
                                                                        releases. EPA has decided to set the
                                                                        vapor pressure criterion at the higher
                                                                        level of 10 mm Hg. In selecting .this new
                                                                        vapor pressure cut-off,  the Agency
                                                                        examined the substances on the      :
                                                                        proposed Iist4hat have vapor pressures  '

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                                          No. 20 /Monday, January 31, 1994 j[ Rules  arid Regulations.   14S3
 of less than 10 mm Hg 'and compared
 the rate of volatilization expected in a
 large release to the rate expected for
 substances with a vapor pressure greater
 than 10 rfim Hg. As expected,
 volatilization rates increase with
 increasing vapor pressure and
 increat/ing pool sizes. The Agency  .
 believes that a timely facility response
 'after the onset of an accidental release
 will likely limit the amount that could
 volatilize'for substances with vapor
 pressures lower than 10 mm Hg, thereby .
 reducing the potential public or off-site.
 impact. The Agehby believes that a  :
 greater amount of substances with vapor
 pressures; .above 10 mm Hg is likely to
 be volatilized and released, even after a
 .timely facility response, occurs,
 potentially causing off-site impacts. The '.
 Agency also reviewed accident history
 and production volume information on ,
 the substance's that .would be delisted at
 this vapor pressure. This review has led
 the Agency to conclude that the    :
 accident histories or production
 volumes associated with the delisted
 substances do not warrant their listing
 under this rulemaking at this time. The
 Agency believes that this revised vapor
 pressure criterion' focuses the list on
 .chemicals that present a greater
 potential for accidental' release than
 would a list using a 0.5 mm Hg
• criterion.      " -      • :  ..',.      ,:
   The new vapor pressure criterion will
 drop from the list some chemicals that
 may have,a lower likelihood of
 accidental release to air. Using ithe new
 vapor pressure criterion, the following
 18 chemicals proposed for listing
 (shown with their CAS Registry
 numbers) will jiot be included in the list
 promulgated today:
 Acetone cyanohydrin (75^-86-5)
 Aniline (62-53-3)-              ,
 Antimony pentafluoride (7783-70-2)
 Benzal chloride (98-87-3)
 Benzenamine, 3-(trifluoromethyl)-
 -        "      ""'  '   •''
 Benzotrichloride (98-07-7)
 Benzyl chloride (100-44-7) ~  "
 Benzyl cyanide (140-29-4)
 Chloroethanol (107-07-3)
 Dichloroethyl.ether (111^-44-4)
 Dimethyl phosphorbchloridothioate :
   (2524-03-0)- V-'    '.-.'•"•     :     v    :
. Formaldehyde cyanohydrin (107—16-4)
 Hydrogen -peroxide (concentration >
 .  52%) (7722-84-1)
 Lactonitrila (78-97-7)
 Pyridine, 2-methyl-5-vinyl- (140-76-1)
 Thiophenol (1Q87-98T-5)
 Trans-l,4-dichiorobutene (110--57-6J   -
 Trichloroethylsilane (115-21-9)
 • EPA will be reevaluatihg the list  .   .
 periodically and as a result of petitions.
 If additional information is submitted
 on the accident history or production
 volume of these substances, EPA may
 list these substances at a later time. In  r
 addition, these substances, as well as  ..
 any other extremely hazardous  /
: substance, are subject to the section
 112(r), general duty clause.
   Accident History: The Agency
 disagrees with-several commenters who
 claimed that the Agency lacked
: authority to list substances based on
 accident history. The accident history
 .associated with the use of a substance,
 in combination with toxicity, physical/
 chemical properties, and production
 volume considerations, is a permissible
 basis for the Administrator to list   •
 substances under section 112(r)< Data
 from recorded accidents relate to each of
 the factors identified in section
 112(r)(4): Such data can provide
• information on. the'severity ptimpacts  ;
 when impacts occur* as well as on .the
 likelihood and magnitude^ of exposure.
 Substances that "are known to cause
 * *  * death, injury, or serious adverse
 effects on human health or the
 environment" may be included on the  .
- list under section 112(r){3). It Would be
 a strained reading of the statute to say
' toe Administrator must ignore
 documented accidental releases of  .
 substance? in deciding which chemicals
 shall be the focus of the accidental   1
 release prevention program.
   The listing criteria established for,
 toxic substances considers not only  •
 acute toxicity, but also physical/
 chemical.properties (physical state,
 vapor pressure), and accident history.
 Several commenters argued that in
 analyzing accident histories EPA should
 not consider: (1) Transportation    ''-/
 accidents; (2) accidents not involving'•>
 death and/or injuries; (3) accidents
 involving.fifes^and explosions; (4)
 accidents involving reactions with other
 chemicals; and (5) accidents involving:
 elevated temperatures and pressures.  •
 The Agency disagrees with these
 comments. Accident nistory may
 indicate, beyond vapor pressure or other
 physical/chemipal properties, unique   .
 qualities or circumstances that warrant   ,
 accident prevention efforts. Evidence
 from transportation accidents may
 indicate the potential for airborne
 releases. For example; chemicals may be
 supplied in containers, such as tank    :
 cars, holding the chemical in similar
 conditions to storage conditions at      "
 stationary source. A failure of a
container while in transit may indicate
the potential for release while at-a fixed ,
location, since it may be stored under
similar conditions. Quantities of  T
chemicals are also commonly held at
facilities for some period of time, in  -   •
trucks, tank cars, and other shipping.
 containers. Accidents that did not result
 irjj off-site deaths or injuries may still
 :W|dicate the serious potential for off-site ,
 inipacts; e.g., evacuations may indicate
 .that there was concern that people "•-"••"'
 cifuld suffer adverse effects from
 exposure. Furthermore; other effects,
 stich as environmental damage, are
 appropriate to consider as weU. While
 th;e facrtors to be considered urider
 selction 112(r)(4j do not specifically  -
 direct EPA to consider envkonmentar
 effects,section iT2(r)(3) directs the
 Aidministrator to consider '"substances :
 which pose the greatest risk of causing
• * :* * serious adverse effects to..* '*'•*
 th^ environment from accidental
 .releases"-. As noted at several points in
 tiis'preambie, EPA believes that its
 decision to consider reported accidental
 rejeasos involving fire and explosions as
 evjents of concern is supported by botn"'-.
 the statute arid .legislative history. See   '
 aliso 136 Congressional Record, S16992
 (d^ily ed., Oct. 27,1990) (statement of
 Sejnator Reid addressing the explosion
 iriiHenderson, Nevada); 136
 Qingrisssional Record H12931 (daily ed.,
 O(it. 2(5,1990) (statement of      ' ' ;,,-,-
 Rffp'resientatiye Barton addressing    '„"'
 releases from burning material); H.R.
 Ccjiif. Rep. No. 952,101st Congress, "2nd
 sejbs.,,0140 (1990) (Board to investigate
 firtes and explosions).,It may also be
 appropriate to consider chemical
- reilcticiris with common materials such
 aslwater; e.g., it may be important to
 consider whether the reaction of an acid
 with water, producing heat,' could lead \
 to iformatipn of an acid vapor or mist
 (tiie Bhopal accident involved a reactipri
 ofmetiiylisbcyanate with water;
 gebterating heat). Accidents resulting    ,J
 fro|m conditions of elevated       '  :
 teinperatures and pressures hi chemical ..
 priicesses may provide important    ,  .',
 information regarding the potential foj.
 accidental releases having an effect bffr
.sitja:'_;.;;'._••;:'.-  ':;. _ ••--.•    ".'-••  •'• '.;
   The legislative history of section  -
 112(r) contains extensiveUisctlssion of
 hiiitoriical accidents and accident history ••
 data to support the need for enacting
 seirtipn 1,12(r) and the particular     '
 provisions included in the legislation.
 S&s 136 Congressional Record Hi 2940
 (didly ed., Oct. 26,1990) (statement of
 Representative Richafdsori); 136
 Cgnigressibhal Record Si6921, S16925-:
 26](daily ed., Oct. 27,1990) (statement '-,
 of ^en?itqr Durenberger); 136   .
 Cobgressiohal Record S16979 (daily ed.,
 O_9jt. 27/1990) (statement of Senator
 Bauc'us). Incidents such as the explosion '
 in; Henderson, Nevada and the releases
 doifnimented in the Acute .Hazardous' '-•:
Evients database, as well as statistics   .
coiJceriiipg the number, of releases arid ,

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 4484     Federal  Register / Vol. 59, No.  20 _/JMonday, January 31,  1994  /  Rules and Regulations
 evacuations were seen as demonstrating
 the need for an accident prevention
 program. See H.R. Rep. No. 490,101st
 Congress. 2nd sess.. 154-157 (1990);
 Senate Report at 211-221. The Agency
 will continue to consider accident
 history, in conjunction with acute
 toxicity and vapor pressure; to
 determine which substances need to be
 listed under section Il2(r), and will
 consider these same elements in any
 revisions to the list promulgated today.
 When determining whether to list a
 substance based on its accident history,
 the Agency will analyze and explain the
 relevance of the accident history to the
 potential for a stationary source to
 accidentally release the substance.
   b. Specific substances. Sulfuric acid,
 phenol, parathion, and nitrobenzene,
 proposed to be listed because of
 accident history, were the focus of a.
 number of comments. As stated above,
 tha Agency believes that accident
 history, as well as toxicity, physical/
 chemical properties, and current
 commercial production volume, are all
 appropriate elements to be considered
 in determining the substances to be
 listed. The Agency reserves the
 flexibility to consider the listed
 substances in light of a combination of,
 or all of these criteria elements.
 Accident history was targeted by several
 commenters as not being a valid criteria
 to uso in listing these substances. As
 discussed above, the Agency disagrees.
 Tho Agency has listed substances that
 meet two or three elements of the
 criteria only; e.g., there are acutely toxic
 substances listed that meet the high
 vapor pressure considerations but have
 no accident history associated with
 them.  By the same token, the Agency
 also believes that commercially
 produced substances that meet the acute
 toxicity criterion and have an accident
 history, still could present a high
 potential for an impact beyond the
 fenccline oven though they do not meet
 tho vapor pressure consideration.
   A number of commenters objected to
 tho inclusion of sulfuric acid on the list
 of substances, noting that because of its
 high boiling point and low vapor
 pressure under ambient conditions, it is
 unlikely to become airborne in a release.
 EPA recognizes that sulfuric acid does
 not meet the vapor pressure criterion.
 EPA originally proposed for listing
 sulfuric add because of its toxicity, high
 production volume, and because it has
been involved in a number of accidental
releases with reported migration of a
vapor cloud off-site; some of these
incidents also resulted in worker deaths
and injuries on-site. Several
commenters indicated that the accidents
dtad by EPA did not provide a valid
 basis for listing for a number of reasons.
 First, some of the accidents, according
 to commenters, actually Involved
 fuming sulfuric acid (oleum), which is
, a mixture of Sulfuric acid and sulfur
 trioxide, and vapor clouds reported
 from these accidents were attributable to
 sulfur trioxide  rather than sulfuric acid.
 Second, commenters stated that the
 injuries in some accidents were caused
 by direct contact with sujfuric acid
 rather than inhalation of vapor. Third,
 according to some commenters, some
 accidents involved reactions of sulfuric
 acid with other substances. Finally,
 comments were received which
 indicated there have been no accidents
 involving vapor clouds of sulfuric aci'd
 that caused off-site deaths or injuries,
 and that, in fact, the. low vapor pressure
 of sulfuric acid makes it impossible for
 an accidental release to have any effect
 beyond the fenceline.
   EPA is well aware that sulfuric acid
 has a low vapor pressure and is unlikely
 to be released into the air under ambient
 conditions. However, as noted above,
 EPA also believes that, exclusive of
 vapor pressure, accident history can
 provide a valid basis, in combination
 with toxicity and/or physical/chemical
 properties, for adding a substance to the
 list. The Agency also notes that nothing
 in the statute limits EPA to consider
 solely the effects  of vapor inhalation as
 a consequence  of a release. As noted
 above,.the EHS toxicity criteria
 endorsed by the Senate are not limited
 to inhalation. Furthermore, death,
 injuries, and environmental impacts
 caused by direct contact are. relevant to
 the risks posed by a chemical.
   While believing the EPA has the
 authority to list sulfuric acid if its
accident history, in conjunction with its
toxicity and significant production
volume, warrants listing, the comments
received by the Agency have created
doubt about the accuracy of what has
been reported as air releases of sulfuric
acid. For purposes of today's
rulemakihg, the Agency has been unable
to determine from accident history
whether sulfuric acid has generated an
air release that has caused impact off-
site. Because of the uncertainty
associated with past reported accidental
release information and the common
confusion between oleum and sulfuric
acid in such reporting, the Agency has
decided not to list sulfuric acid at this
time. Although  sulfuric acid is not
specifically listed, facilities handling
sulfurie acid are still subject to general
duty requirements. The Agency will
continue to monitor and review sulfuric
acid accident reports to determine the
need for listing  at a future time. EPA   '.
also seeks data on the off-site impacts of
  sulfuric acid that could be used to  •  •
  evaluate,whether sulfuric apid should
  be added to the list.   .   -  ..
    Related to the sulfuric acid issue are
  comments suggesting that the Agency
  specifically list oleum (fuming sulfuric
:  acid), CAS number 8014-95-7. Oleum
  is a mixture of sulfuric acid and sulfur
  trioxide. In the proposed rule, the.
  Agency believed oleum would be
  subject to section 112(r) requirements
  because both of its components, sulfuric
  acid and'sulfur trioxide, were proposed
•  for listing, and because of the Agency's
 'proposed de-minimis concentration for
  mixtures. However, two commenters  •
  noted that it is "reasonable to include
  oleum as a regulated chemical" and thai
  "oleum and sulfuric acid must be listed
  separately, since the fuming effects of an
  oleum release make it potentially much
  more serious." The Agency agrees with
  commenters that oleum should be
.  included in this  listing because of its  '
  accident history, toxicity, and
  production volume. Furthermore, the
  Agency has reviewed the accident
  history data relevant to oleum and
  sulfuric acid and agrees with
  commenters that some of the accidents
  the Agency had relied on to list sulfuric
  acid in fact involved oleum.
  Furthermore, because of the revisions . -•-
  on the de-minimis concentration
  provisions and the Agency's decision
  not to finalize the listing of sulfuric acid
  at this time, oleum would no longer be
  subject to 112(r)  provisions withoufa
•;  specific listing. In order to continue the
  coverage of oleum in the accidental
  release prevention provisions, EPA is
  specifically listing all forms of oleum in
  the section 112(r) list of-substances.
  . Phenol (in liquid form only),
 parathion, and nitrobenzene are also
 included on the proposed list based ori
 accident history. Several commenters ,
 objected to the inclusion of these
 chemicals, for reasons similar to those
 concerning the listing of sulfuric acid,
 i.e., the low vapor pressure of these
. substances arid the lack of sufficient
. supporting accident history to provide a
 basis for listing. The Agency generally
 agrees with the comments regarding
 these three specific substances. Having  •
 considere'd the comments and having
 conducted further review of accident
 history for these chemicals, the record
 indicates that there are not a. clearly
 significant number of accident reports
 with  effects, or potential effects, beyond
 the fenceline to merit listing at this
 time.
   Several commenters objected to the
"listing of other specific substances for a
 variety of reasons, including low vapor
 pressure, low toxicity, existing safety
 regulations, and'accident history. The

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           Federal Register / VoL 59, No.  20 / Monday,; January 31>1994 7
 chemicals mentioned include hydrogen
 peroxide, acrylonitrile, and
 hydrochloric acid, among others. EPA
 has reviewed the comments on these •
 chemicals and categories of chemicals
 that were recommended for deletion
 'and has decided to, except as noted,
 retain them on the list of regulated   ,
 substances under section 112(r}. As
 noted above, EPA is.revising the vapor,
 pressure criterion and hot proceeding to
 • h'st 18 chemicals with vapor pressures
 below 10 rnm Hg. In addition; the
 Agency has determined that section
 112(rJ(3) prohibits it from listing methyl
 broinide because the substance has been
 listed by regulation as an ozone       '
 depleting chemical under CAA Title VI
 (see 58 FR 65018, December 10,1993).
   The Agency disagrees with   _
 commenters that seek deleting
 substances because of other existing .-••
 regulations. The listing of substances
 and thresholds, as mandated by  ,   '
 Congress, reflects the potential for these
 listed substances to cause serious
 adverse effects to human health or the   .
 environment. The Agency believes that
 considerations of other regulations
 applicable to these regulated substances
 are appropriately accounted for In
 accident prevention requirements
 developed for facilities handling the   '
. regulated substances above the       \
 threshold quantities; rather than in
 determining whether any listed
 substance poses  a potential hazard.
   Several commenters recommended
 , the deletion of substances that were
 mandated for Hsting by Congress,   "  .
 including ammonia, toluene
 diisocyanate, and anhydrous sulfur
 dioxide. The Agency believes that the
 language of section 112(r)(3) precludes
 it from omitting these chemicals from ',-'-
-the initial-list The Agency will consider
 petitions to delist these chemicals if
: such: petitions, comply with the petition
 criteria announced today.  -      •.'•."'
   Several commenters recommended
 adding other specific substances, such
 as chlordane and tetraethyl lead, to the
 list of regulated substances. The Agency^
 will consider these at the time it revises
 the list promulgated today, or through
 the petition process. However, the
 Agency notes that notwithstanding  ;
 today's listing, these substances are still
 subject to'the general duty provisions,
 • particularlyaf they are in commercial
 production and use. ;,   ,
   In the list rule proposal, EPA
 , requested information to determine the
 need and appropriateness of including
 radionuclides under this rulemaking.
 Some commenters objected to including
 radionuclides while others
 recommended inclusion. Still other
 commenters recommended the
 inclusion of only some radionuclides.
 Howeyer, none of the commenters   ',."';
 provided sufficient technical  -,'
 information to assist the Agency in
 determining whether or not       ;
 radionuclides should be listed. Due to
 the uncertainty associated with gaps in
 EPA's data and the appropriate'eriterfa
 for listing, the Agency has decided not
 to include radionuclides in the initial
 list of regulated substances.   '
  ; c. Oihevlisi options considered. EPA
 considered the option of adopting the
 entire list of 360 toxic chemicals
 regulated under EPCRA (SARA Title IH)
 section 302. A small number of
 commenters favored this option,.    •;
 believing that consistency with EPCRA
 is desirable, that having a single list
 would help avoid confusion, and that
 listing additional toxic substances •'
 would be more protective of the public.
 EPA did.not propose to adopt the entire
 EHS list because it includes a number
 of solids and non-volatile liquids for
 which an effect beyond the fencelihevin
 the event-of an accidental release is  ,',
 expected to be less likely than for    '
 gaseous or volatile liquids. It also
 includes substances that are not
 currently in commercial production..
 Congress did not direct EPA to list all
 EHS substances. Instead, Congress
 provided that the Administrator could
 include as few as 100 substances on the
 initial list under section 112(r). In
 'directing the Administrator to "use" the
 EHS list, but hot to be "limited''.to" this
 list, and in providing that "such      :'"
 modifications as * _ * * appropriate" be
 made, the CAA provides the Agency
 with the flexibility to cull from die EHS
 list and other sources a more focused  "
 list of substances for accidental release
 prevention regulations. Most       ,  ;:
 commenters supported EPA's decision
 to propose for listing only those EHSs
 that.best reflect the statutory criteria of
 Ukelihobd and magnitude of release; For
 •these reasons, EPA is not adopting the
 entireEHSlisL                   ;
    d. Threshold quantities. EPA's    ;
 proposed thresholds were lower than
 OSHA's for 15 of the substances listed
 by both OSHA and EPA. A number of
 commenters stated that EPA's    .
 thresholds should not be lower than
 OSHA's for any listed substances; since
 in general, workers: face a more
 immediate threat of exposure-in an
 accidental release than would the
 public. Several commenters indicated
 that EPA should adopt the OSHA    .
 thresholds for chemicals which EPA
;: had assigned lower thresholds.   ,     •••
 Conversely, there were other comments
 supporting, the lower thresholds
 ; proposed by EPA for several chemicals,
 based on tlie eommenters' -experience
 .with these chemicals.             .   :
   EPAJ has reviewed the threshold    ,
 quantities for the listed substances and
 the OSJHA thresholds for the substances
 on both the EPA and QSHA lists prior -
 to andjafter the proposal of EPA's rule.  ,
 EPA rocogiiizes the practical importance
 of conisistency with, the QSHA list to the
 extent|pos!5ible, but also believes it i$
 neces^^ry ftb have a sound methodology"
 for assignment of threshold quantities;
 the C^|A n>quires the'Agency to include
 an expjlaneition of the basis for
 estabflshing the list, and to account for
 specified factors hi setting threshold
 quantises". OSHA's thresholds were not
 required t<» reflect the factors EPA must
 consicler. The statute also provides for
 petiticjhs to add new chemicals,,and   :.
 requirps thte development of thresholds,
 for siMsh diemicals when listed. A    ,
,'>ound|methodology is essential for
 making changes to the list and - _.-.  .
 threshplds after promulgation. The   /:.
 methcidolcigy adopted today considers
 the faistprs required by the CAA under
 sectiojii'il 2(r)(5). No other methodology
 was identified that EPA could use to
 derive| thresholds that would be
 consistent and equally applicable to the
 current listed substances and to those
 that miay be addedIn the future.
 Therelore, EPA is hot adopting the
 OSHAf thresholds.               ---,-
   Neyferth'Bless, EPA agrees with
 comm&hters that EPA should review its
 prdpdged'iteeshbld methodology and  '
 quant'Jty categories to ensure that ftey,
 , accurately reflect the range of risks,
 posed by the listed toxic substances.    :
 Based on this review, EPA .has decided
 to retain its threshold methodology but •
 revise the range of threshold quantities
 for toitics. The minimum quantity
 rematis at 500 pounds, representative, of
 drum-size containers, but the maximum
 threshold quantity is raisedtb 20,000
 pounds, replacing the proposed 10,000
 pound maximurn. This higher upper    „
 limit expands the range of threshold
. quantiities to better reflect the relative
 hazards among the listed toxics; the,
 upperjlimit of 20,000 represents typical
 handlfng (quantities, and would still be -'
, protecitiye pfthe public for those
 substsijices which now have the higher
 thresholds!. Thresliold quantity
 categciries for toxic substances are now:
 500 pounds, 1,000 pounds, 2,500
 pounds, 5,000 pounds, 10,000 pounds,:
,15,00(5 pounds, and 20,000 pounds^ ...
   Usijag this revised .range, higher    :
 ,thresli|Qld« have been assigned for most ,
 ofAejtpxic substances listed based on
 the re'vised vapor pressure* criterion.
 rSeverjil. taxic substanpes also meetthe  ,
 flampmbility criteria, and thus could be
 assigrled two thresholds^ Toxic  '

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4486      Federal Register  / Vol.  59,
                                                              January 31, .1994 / Rules and-Regulations
  substances that also meet the criteria for
  listing as flammable substances are
  assigned the lower of the thresholds.
  Under the revised methodology, the
  only substance that has a threshold
  quantity that is lower under EPA than
  OSHA's PSM standard is methyl
  chloride, which meets the criteria for
  listing for flammability and, therefore, is
  assigned a threshold quantity of 10,000
  pounds, rather than the 20,000 pounds'
  that would apply under the
  methodology for toxiqs. The OSHA
  threshold for methyl chloride is 15,000
  pounds. This is to account for those
  hazards presented by the substance that
  are considered in this rulemaking; the
  lowest threshold quantity is assigned to
  be more protective.
    A number of commenters suggested
  that site-specific factors should be
  considered in setting or modifying
  thresholds, such as population density,
  ecosystem sensitivity, safety devices,
  experience, uses of the substance, and
  handling conditions. EPA recognizes
  that these and many other site-specific
  factors could affect the likelihood of
  occurrence or the effects of a release.
  Accounting for these factors has the  -'*
  advantage of more specifically tailoring
  threshold quantities based on common
  usa patterns of the substances and on
  the particular site in which they would
  bo used. One serious disadvantage of
  applying site-specific factors to setting
  thresholds would be that such an
  approach would be inappropriate for
  ubiquitous chemicals, such as chlorine
  and ammonia, because of the
  innumerable applications that would
  have to ba considered. A greater
  disadvantage to this approach is that the
  intrinsic hazard of a chemical will still
 ba present oven when it is used outside
 of a "typical" scenario. As stated in the
 proposed rule, EPA believes it is not
 feasible to develop a methodology for
 establishing threshold quantities based
 on site-specific factors that would be
'applicable uniformly nationwide.
 Therefore, EPA did not incorporate site-
 specific factors in setting or modifying
 thresholds. As discussed in the
 preamble section IV.B. Threshold
 Determination, substance-specific  •
 factors and use scenarios are considered"
 in determining whether there is a
 threshold quantity on-site. Also, site
 specific factors will more appropriately
 ba accounted for in the accidental
 release prevention regulations under
 section 112(r)(7). This Agency rationale
 is also applicable to similar comments
 for establishing thresholds for
 flammable and explosive substances.
  o. Other threshold quantity options
 considered. In addition to the proposed
'methodology for setting thresholds for
                                      toxic substances and the use of OSHA.
                                      thresholds as discussed above, EPA
                                     , requested comment on severarother
                                      options. One option was use of the
                                      .vapor quantity method, based on air •
                                      dispersion modeling, to determine the
                                      quantity in air needed to equal the
                                      "Immediately Dangerous to Life and  •
                                      Health" (IDLH, published by the
                                      National .Institute for Occupational
                                      Safety and Health) concentration level
                                      at 100 meters from the point of release.
                                      This option was not generally supported
                                      by commenters. A second option was to
                                      adopt the threshold planning quantities
                                      (TPQs) under EPCRA section 302. A
                                      small number of commenters favored
                                      this option, believing that consistency
                                      with EPCRA would help to avoid
                                      confusion. EPA did not propose this
                                      option because the TPQs are intended to
                                      represent a level at which the chemical
                                      hazards should be considered by
                                     • localities for discretionary community
                                      planning purposes.' As mentioned in the
                                      preamble of the proposed rule, the
                                      thresholds established under this rule
                                      have a different purpose, i.e., to indicate
                                      which facilities ntust comply with
                                     mandatory facility-based prevention
                                     requirements. Any confusion that :
                                     results from two different threshold -,'
                                     quantities applying to the same
                                     chemical under two EPA emergency
                                     preparedness and prevention programs
                                     is mitigated by the fact that the more
                                     onerous and detailed planning
                                     requirements are triggered when greater,
                                     and presumably more dangerous,
                                     quantities are present.
                                       The third threshold option considered
                                     for toxics was adoption of the OSHA
                                     thresholds for all substances listed by
                                     both EPA and OSHA. A number of,
                                     commenters favored this option. As
                                     noted above, EPA recognizes the,
                                     importance of consistency with OSHA.
                                     However, because of EPA's statutory
                                     obligation to establish a methodology
                                     based on.specified factors, the Agency
                                     has elected not to adopt the OSHA
                                     thresholds. The thresholds adopted in
                                     today's rule for chemicals listed by EPA
                                     are, with the exception of methyl
                                     chloride, equal to or higher than
                                     OSHA's.

                                     2. Flammable Substances
                                       EPA's listing of flammable gases and
                                     volatile flammable liquids was generally
                                     supported by commenters, although a
                                     few commenters maintained that,
                                     because OSHA regulates flammable
                                     substances, EPA should not list them.  :
                                     The Agency disagrees that flammable
                                     substances should not be listed for
                                     accident prevention and potential
                                     effects off-site, since such substances
                                     pose a potential off-site hazard (namely,
  a vapor cloud explosion) because of
  their inherent properties. The proposed
  threshold for flammables, 10,000
  pounds, was generally supported as
  well. EPA is finalizing the proposed
  listing for flammables and their
  threshold quantities',            : . •
    ^Commenters also focused .on specific
  flammable substances, including
  methane, ethane, propane, and butane
  (some components of natural gas),
  Commenters argued that special factors
  (e.g., the low density of methane gas)
  justify not listing or modifying the
  listing of these substances. EPA has
  reviewed the comments on specific    ;
  flammable substances and disagrees
  with the commenters. EPA believes
  there is sufficient information, from
  both accident reports and modeling
  results, to support the conclusion that
  flammable substances that meet the
  listing criteria, in quantities abdve the
 .threshold quantity of 10,000 pounds,
  could present a hazard to the public
  from a vapor cloud explosion. EPA
 , recognizes that, as noted by
  commenters, some situations in which
  these substances are handled may
  present a lesser hazard than others.
  However, these substances still pose, a
  potential threat beyond the fertaeline in
  case of an accidental release. Therefore,
  in order to be protective of the public,
 EPA is maintaining the same          .
 application of the criteria for flammable
 substances as.proposed for all listed
 flammable substances. EPA's listing
 decision is based on the substances'
 demonstrated or potential effects in the
 event of'an accidental release, not on
 existing regulations, standards, or
 recommended practices applicable to
 the listed substances; these factors may
 more appropriately be accounted for
 .when accident prevention regulations   :
 are promulgated under section 112(r)(7,'.
   Several commenters recommended   '
 that EPA provide an exemption, similar
 to the exemption under OSHA's PSKl
 Standard, for flammable liquids kept in
 atmospheric tanks below their normal
. boiling points. Unlike OSHA, EPA is "
 listing only flammable gashes and
 volatile flammable liquids. EPA
 considers these substances to be
 intrinsically hazardous, regardless of
 conditions of storage, and, therefore,
 does not believe it is appropriate to
 provide an exemption for atmospheric.
 storage.    .     •••  .

 3. Explosives         -            U/
.   Explosives classified by DOT as Class
 1, Division 1.1 and listed as such in 49
 CFR 172.101 (the Hazardous Materials
 Table) are covered by this rule with a
 threshold of 5,000 pounds. In 49 CFR
 173.50, DOTdefines the term .    : '   .
   I!
   I
-J-'l
-; . :lj
.'  If

-------
     "explosive" as any substance or article,
     mcluding a device, which is designed to
     function by explosion (i.e., an extremely
     rapid release of gas and heat) or which,  >
     by chemical reaction within itself, is
     able to function in a similar jnanner
     even if not designed to function by
     explosion, unless the substance or
     article is otherwise classed under DOT
     provisions. Division 1.1 consists of
     explosives with a mass explosion
     hazard;' a .mass explosion is one which
    .affects almost the entire load
     instantaneously. The Agency proposed
     to list all substances that met the
     definition of Division I.I (58 FR 5110)
     The Agency is clarifying and modifying
    its listing of explosive substances to
  ,  include only those substances listed in
    49;CFR 172.101 (DOT'S Hazardous
 :   Material Table), which is a subset of all
    substances and mixtures of substances
    that would meet DOT's Division 11
    definition.    ....;,                '   "   :
     EPA noted in the preamble to the
    proposed rule that it believed this
    threshold would apply primarily to
    manufacturers of high explosives (58 FR
    5112). More than 100 commenters,
    primarily explosives distributors and
    users, objected to the listing of
    explosives in general. These
    commenters maintained that explosives
    are regulated adequately by a number of
   agencies, including the Bureau of  '
   Alcohol, Tobacco, and Firearms (BATF1
   DOT, OSHA, the Mine Safety and
   Health Administration (MSHA), and the
   Department of Defense (DOD). The
   commenters believe the requirements of
  the existing regulations serve to prevent
  accidents and cited the safety record of
  the explosives industry as evidence: The
  commenters believe the American Table
  of Distances, used by BATF to set
  distances for storage of explosives,
  provides protection for the community
  from the effects of an accidental
 , explosion; this table is based on a lower
  overpressure level than the 3.0 psi used
  by EPA to setthe threshold for
  explosives and, therefore, is more
  protective of the public. In addition, a
  number of commenters said the 5,000-
  pound threshold proposed by EPA
  would not restrict the effects of the rule
  to manufacturers, as suggested by EPA,
. but would also cover many distribution  ~
  and use sites; They noted that, for
  example, blasting may require only a
  small quantity of high explosive  :
  (Division 1.1), but that the entire ,
 quantity of explosives on-site used in
 blasting is treated as a high explosive;
 the high explosive portion serves to
 initiate the.reaction involving the entire
.quantity.             ;
   PA acknowledged in the proposed
 mle that explosives ate already   '  " :
    regulated by a number of agencies.   ;.
    However, these existing regulations do
    not negate the properties of these
   . substances. The explosives listed in
    today'srule meet the criteria of section
    112{r) (3) .and (4) because the inherent
    properties of the listed explosives
    plainly indicate that such chemicals
    may have a severe impact in the event
    of a detonation. The listed explosives
    represent the category of explosives that
    may most easily detonate. In the event
    of an accidental detonation these
    substances pose an inherent risk of off-
    site effects. Industry requirements under
    other applicable regulations, or :
   recommended standards, are more
   appropriately accounted for in  the
   development of accidental release
   prevention requirements. The
   requirements for accident prevention  in
   section 112(r)(7) specifically allow for
  . recognition of iridustry-specific
   circumstances, including voluntary
   prevention measures, in EPA's
   prevention regulations. No similar
   provision is set forth in sections 112(r)
   (3), (4), or (5), which covers the
   development of this list of substances
  and thresholds quantities. Section
  112(r)(7) implementing rules,,as
  appropriate, Will allow for industry
  specific circumstances to be considered.
  Other regulatory requirements, and
  other practices already "in place aimed
  specifically at protecting the public
  from adverse effects In case of         :
  accidental releases are expected to be
  integrated Wito accident prevention
  requirements of rulemaking under
  section 112(r)(7).
    ^particular, EPA's review of existing
  regulations indicates.that public safety
  would be enhanced if additional
  information about explosives, such as '  .
  hazards assessments, were available to
  emergency response agencies and local
  emergency planners. Public safety
  would also be enhanced if there were
  additional coordination between
 facilities handling explosives and the
 local emergency planners and
 responders. The listing of explosives
 will make information available under
 section 112(r) rulemaking and facilitate
 this coordination. Furthermore, current
 regulations do not provide for public
 communication of potential off-site
 hazards, as do CAA Amendments      -
 requirements imder section I12(r)(7)l
 Currently, only information related to
 the quantity and location of explosives
 is available to the public-under sections
 311 and 312 of EPCRA. Under the risk
management provisions of the GAA the
public will also have available to them
information about the measures being
taken by the. facility to prevent off-site
                                    4487

    [•consequences from accidental
    [detonations.1       -         '       !,  •
   1;:The Agency has noted that the
    practice of treating the entire quantity of
    mixtures of high explosives with other
    .explosives as'high explosives, coupled
   ^witfci the Agency's proposed threshold
   ^termination rule for mixtures, creates
   .toe potential for coverage of explosive
    formulations that are intended to be
    Ceased (exploded) on-site. The Agency
    Rid not intend such coveragein its
   'proposal. Jn response to this problem
   Identified by the commenters, the
   Agency is modifying the listing of
   explosives in today's final rule so that  ;
   {Specific explosives oni the Hazardous
   Materials Table are identified as the ;
   ipgulated substances. This avoids the
   potential circularity in the proposed
   definition. Mixtures withsubstances
  Jtstecl on,the Hazardous Materials Table
   are,potentially covered only, through the
   operation  of the explosive mixture
   provision in toe threshold
   djetenmination portion of today's rule
   1'he Agency is also clarifying the    "
   coverage of explosive mixtures.to be
   used jfor intentional on-site detonation
   (not an accidental release) when
   determining if a threshold quantity is
  p^aitin a process. This clkrificationisx
  discussed l^ter in today's preamble.
  B  Threshold Determination  ••..?•/••-.   ''...''
    Secflion 68.115 was driginally
  pipposed as section 68.5. It has been '
  ccnsoMdated with other subpart C
  piovisions that relate to covered
  substances and applicable thresholds
  Tlus ajction of the regulation
  e|tablishes how to estimate the presence
  of |a threshold quantity. Exemptions of     -~
  those quantities that need not be.
  apcourrted for in determining a
  thiresh(3ld are also included.
  I".^^ Basis for Threshold Determination
   Comments on the proposed rule
  geiierally supported a threshold     .
  quiuitity determination that is based on
  the} quantity of a regulated substance in  -.
  a process. Some commenters, however
  suggested that determining threshold '
 quiintities should be based on the
 quality ori-site, the average annual
 usage, or on-site specific factors. EPA
 generally disagrees with these -
 stat:ements. The total quantity on-site
 wmle ODnsistent with other regulations
 in determining threshold quantities"
 (paiticularlyEPCnRA, section 302) does   '
 not necessarily represent the quantity
 that| could be involvedin an accident
 Thej total quantity 6h-site may include
 quaatities in separate processes,
 buildings,.and locations within the
 san^e facility. The average annual usage
measures the quantity used by a facility

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 4488
Federal Register / Vol. 59. No. 20 / Monday. January  31.  1994  /  Rules and
 in a year and is not related to the
 maximum quantity that could be
 released at a given time. Site-specific
 factors are appropriately accounted for
 both in defining the process for which
 a threshold calculation must be
 undertaken and in assessing the hazards
 and preparing the risk management plan
 for the particular facility. As
 recommended by most commenters,  .
 EPA Is retaining the threshold
 determination based on the total
 Quantity In a process, using the same
 process definition as OSHA. This
 approach focuses on the quantity of a
 substance that might be released in a
 single accident, and that could be
 reasonably anticipated to cause effects
= of concern as a result of an accidental   .
 release. This threshold determination
 approach is consistent with OSHA's
 PSM standard.
  2. Mixture Exemption
    a. Toxic substances. The proposed
  rulo included a de-minimis
  concentration of one percent by weight
  for all listed substances present in a
  mixture'; i.e., quantities of a regulated
  substance in a mixture did not have to
  bo accounted for purposes of the
  threshold quantity if the substance were
  present at concentrations below one
  percent by weight. A number of
  comments were received on this
  exemption for solutions and mixtures.
     Several commenters suggested
  providing a threshold determination
  method for mixtures based on the SHI.
  The partial pressure of the listed
   substance in solution and its toxicity
   would be used to determine the value of
   tho SHI for the solution; the index value
   would be compared to a cut-off value
   (commenters recommended a cut-off of
   1,000). EPA does not agree that the SHI
   criteria should be used to determine the
   mixture cut-off. Because the SHI
   approach was not used in determining
   which chemicals to list, a mixtures
   score based on this index would not
   rolato to whether a chemical met the
    listing criteria. EPA also remains
    concerned about the lack of a basis for
    the recommended 1,000 SHI cut-off. In
    addition, EPA believes the SHI
    approach would be difficult to .
    implement within the structure of
    section 112(r), especially for facilities
   " outside the chemical manufacturing

      Most of the commenters believed the
    one percent concentration cut-off is toe
    low for solutions of toxic substances;
    their position being that one percent
    mixtures of a regulated substance pose
    essentially no threat to the public.
    Several commenters also suggested that
    EPA should provide specific
                            concentration cut-offs for solutions of
                            certain listed substances, such as
                            hydrogen fluoride, nitric acid, and
                            sulfuric acid. Several commenters
                            suggested that the concentration cut-offs
                            should be raised for hydrochloric acid
                            (listed for concentrations of 25 .percent
                            or greater) and ammonia (listed for
                            concentrations of 20 percent or greater}.
                              The Agency agrees with commenters
                            that the one percent cut-off may, prove
                            to be too conservative in certain
                            circumstances, and that it may not
                            adequately reflect the decreased
                            potential for air release of most
                            regulated substances in dilute mixtures
                             or solutions; at very low concentrations
                             some of these mixtures or solutions fail;
                             to meet the listing criteria. The Agency
                             also believes, however, that no
                            • justification would exist to exclude the
                             quantities in mixtures or solutions from
                             the threshold calculation if it is     .  :
                             uncertain that these mixtures or
                             solutions fail to meet the  original listing
                             criteria.                       en 4
                               In response to these comments, E.FA
                             has modified the one percent mixture
                             exemption to reflect the amount of the
                             regulated substance that may reasonably
                             be anticipated to cause an effect of
                             concern iji an accidental release. The
                             Agency has reassessed the concentration
                             at which certain dilute solutions of
                             regulated substances may pose a hazard,
                              to the community, sufficient to warrant
                              treatment as a regulated substance, for
                              purposes of determining whether a
                              threshold quantity is present in a
                              process. As part of this modification,
                              EPA has decided to provide specific cut-
                              off concentrations for certain chemicals.
                              These chemicals, in mixtures or
                              solutions with concentrations below the
                              specified cut-off, will not have to be
                              considered in determining whether a ..
                              threshold quantity is present. For other
                              chemicals, a method, rather than a
                              specific cut-off, will be provided to
                               determine whether mixtures should be
                               considered in the threshold
                               determination. The following chemicals
                               are now listed with concentration cut-
                               offs (hi addition to those already
                               proposed with concentrations cutoffs)
                               as shown for weight percent of the
                               substances in water solution:
                                 » Hydrogen fluoride/Hydrofluoric
                               acid (concentration 50 percent or
                               greater); the listing of hydrogen fluoride
                               has been clarified to reflect that it
                               includes the aqueous form of hydrogen
                               fluoride, hydrofluoric acid.
                                  •"Nitric acid (concentration 80
                               percent or greater).
                                  The concentration limits for
                               hydrofluoric and nitric acid are based
                                on the partial pressures of these
                                substances in water solution. At the
Concentrations listed, the partial
pressures of the solutions would meet
the vapor pressure criterion of 10 mm
Hg. Also, EPA is raising the proposed
concentration cut-off for hydrochloric
acid from 25 to 30 percent, based on
Water solutions, to meet the revised
 vapo'r pressure criterion. EPA is not
 changing the concentration cut-off for
 ammonia because the partial pressure of  ,
 ammonia in a 20-percent solution still
 exceeds, the 10 mm Hg vapor pressure
 criterion.                   .
   Other listed toxic substances in  "
 solutions or mixtures must be included
 in threshold determination if the partial  ,
 pressure of the substance in the solution
 or mixture is equal to, or exceeds, 10
 mm Hg. If the partial pressure of the
 regulated toxic substance in the mixture
 is determined to be below 10 mm Hg...
 •under all conditions in process handling
 or process storage, the solution or
 mixture need not be considered in the
 threshold determination. If the partial
 pressure of the regulated toxic substance
-  in the mixture equals or exceeds 10 mm
  Hg in portions of the process, then the
  quantity of the listed substance
  contained in'the mixture at these
.  portions of the process shall be included
  in determining whether a threshold is
  met, The facility will be required to use
  the one percent de-minimis          _
  concentration in determining threshold
  quantities unless it can measure or
  estimate, and document, that the partial
  pressure of the regulated substance in
  the mixture or solution is less than 10

    The methodology for determining the
  amount of a regulated substance in a
  mixture to apply to thresholds does not
   apply to oleum, toluene 2,4-
   diisocyanate, toluene 2,6-diisocyanate,
   and toluene diisocyanate (unspecified
   isomer). These substances have Vapor
   pressures less than 10 mm Hg.
     b.Flamma ble substances. The
   •proposed rule included the same de-
   minimis concentration of one percent by
   weight for all listed substances present
   in a mixture for flammable substances.
   •A number of commenters noted that
   mixtures of flammable substances in
   concentrations above one percent may
   not be flammable. They suggested that
   a listed flammable substance in a
   mixture should be included in threshold
    determination only if the mixture meets
    the flammability criteria for listing.;
    Other commenters suggested that the
    entire mixture containing a listed
   .substance should be treated as a
    regulated substance if the mixture meets.
    the listing criteria for flammable
    substances. EPA agrees that a mixture
    containing a listed flammable substance
    should only be considered in a

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                                                                                    i                ,_

             Federal Register / Vol.  59,  No. 20 /Monday. January 31, 1994 /  Rules and Regulations     4489
  threshold determination if the jnixture
  itself meets the criteria for an NFPA
 ,-flammability rating of 4, i.e.. flash point
  below 22.8° C f 73° F) and boiling point
:  below 37,8° C (100° F). Again, as for the
  toxics in mixtures or solutions, a facility
 ! is required to use the one percent de-
  minimis concentration for trires^
  quantity calculations unless it can
  measure or estimate, arid document, that
 .the mixture or solution does not have a
  flash pointbelow 22.8° C (73° F) and a
  boiling pciint below 37.8^ C (100° F). ...-
    The Agency agrees with cOmmenters
  who suggested that a mixture containing
'.-.- a flammable regulated substance should
  be treated as the regulated substance for
  purposes of determining whether a
  threshold quantity is present if the
  mixture itself meets the boiling point.  "
.  and flash point criteria of today's rule.
  EPA believes the hazards associated
  with such highly flammable mixtures
  make it appropriate to treat such
•i mixtures as regulated substances when  .
  such mixtures meet the flammability
  listing criteria. EPA recognizes that
  counting the entire quantity of a
  flammable mixture for threshold,
  determination differs from the proposed
  rule and from the treatment of mixtures
  containing regulated toxic substances.
  However, the Agency believes this  ,
 ' different treatment is appropriate
  because, for flammable substance
  mixtures, the mixture is known to -
  display the flammability hazard at
  levels that meet the listing criteria,,
 •while for toxic substance mixtures, the
 mixture is not known to meet the acute
 toxicity criterion. For toxic substance ...
 mixtures, EPA requires counting
 towards a threshold only the portion of
 the mixture that would meet the acute
 toxicity criterion (i.e.> the amount of the
 actual substance).            ,     ,
    c. Explosive substances, A number of
 -comments were received regarding the
 threshold calculations for explosives,  :
 particularly for mixtures of division 1.1
 ^explosives with low explosives or ;  :
 blasting agents at use sites. In the
 proposed rule, the Agency had    •     "
 established a de-minimis concentration
 applicable to all listed substances.  ,
 Cornmenters pointed out problems with
 this mixture consideration, in light of
 EPA's listingof all explosives meeting
 POT's definition of Division 1.1
 hazardous materials.This definition
 treats the entire quantity of a mixture
 containing a high explosive as a
 Division 1.1 explosive, hence negating
 the de-minimis calculation for purposes
-pf threshold quantity determinations.-
 This, affected particularly those mixtures
 formulated on-site, prior to intentional...
 detonations, following BATF   •  ,  ,
 regulations. TO minimize the potential
  for accidents, these mixtures generally
  are made shortly before intentional on-
  site explosions. The Agency recognizes
  that the intentional release (or
  controlled release) in an explosion of
  mixtures containing a regulated
  substance is not an accidental release;
  Thus, the Agency believes that the
 .amount of an explosive, in such a
  mixture cannot be reasonably
: anticipated to cause effects of concern
  as a result of an accidental release when
 ". such quantities are intended to be
  released on-site. Therefore, in addition
  to clarifying the listing of explosives
  only to include those substances listed
  by DOT in 49 CFR 172.101, the Agency
  is also clarifying the applicability of the
  mixture .concentration provision for
  explosives. Fai purposes of determining
  whether a threshold quantity is present
  in a process involving explosives,
 mixtures of Division 1.1 explosives
  listed by DOT in 49 CFR 172.101
  (Hazardous Material Table) and-other
 explosives need not to,be.included
 when the mixture is intended to be used
 in an-on-site non-accidental release in a
 manner Consistent with applicable
 BATF regulations. Quantities of
 explosive regulated substances in
 mixtures that are not intended to be
 used on-site in an intentional explosion
 would not be exempt if such mixture
 would be treated "as a Division 1.1
 explosive under 49 CFR parts 172 and
':173. ,'.-  /  /-«•' '/. - -... •:•/ ...• V'  .'-;•''' :.;.

    The following two examples
 demonstrate how this threshold     ,
 determination provision would operate.
 An owner or operator of a stationary
 source receives a mixture, or prepares a
 .mixture, that: combines a small quantity
^of an explosive listed as Division 1.1
 hazardous material in 49 GFR1721101
 with a large quantity of a blasting agent,
 so that the total quantity is above the
 5,000 Ibs threshold quantity established
 for listed explosives. If the owner or
 operator intends to'detonate the high
 explosive/blasting agent mixture at the
 stationary,source in a manner that is
 consistent with applicable BATF
 regulations, then the owner or operator
 need not count the weight of the        ',-
 mixture in determining whether the
 source has a threshold quantity of the
T regulated substance on-site. If the-owner
 or operator intends to store, and then
 transport off-site the high explosive/
 blasting agent mixture, and the entire
 mixture would be treated as Division 1.1
 explosive under applicable DOT:
 regulations, then the weight of the entire
 mixture would need to be calculated to
 determine whether a threshold quantity
.is present.
      }•_<-,'     ,    •   '   ••    -   ,  .  '
  3^ Other Threshold-Exemptions
.  - .   j: • • '  - -. '. ... :•..-! ' . .' .  r  '    •  '- . .-.•.-.
   Except as rioted below, all other
  threshold;exerriptions in the proposed
  rule are retained in the final rule. All
  cordirieints received concerning these
,  exeipptioris favored the Agency's
r projiosall. The Agency continues to
••:• beli(sve that the forms of regulated
  substances exempted .in today's rule
-". canitotri3^s6riably be anticipated to
  causle.efifects of concern hi flie eyent of
; anabcidentalreieasel,            "'
;   Use for facility, consumption as fuel:-
 The Agency has deferred a decision on
  the proposed exemption for listed    1
 .flanimable substances when used solely
  for facility consumption as fuel. Fora  •
  dociiment relating to this proposed:
  exeiiiption, see a supplemental notice
,  published elsewhere in this issue. The
  Ageiicy intends to decide on whether to
  pronaulgate this exemption on or before
  the date the final risk management
  program rule is promulgated,

  C. Petition Process
   Section68.120 of'the rule establishes
  the specific administrative and  .
 techj:ucal requirements for the ;
'^submission of petitions to add or, delete
' substances from the list of regulated
 ;subs:fanciBS. --- '     •  •'"  ' -.  •; '-,' -.'"' :'.'
   Several comments were received on
 the catena for determining whether a
 substanciBi that is the subject of a petition
 should bi3 listed or deUsted. Two
 conunenters said  the listing criteria are
 too piafeow. For example, it was argued
 that 1EPA should allow petitioners to
 develop a case for listing toxic
 chendcals.that do not meet the acute
^ toxicjty criteria. Another cbminenter    -
 said the listing criteria are too broad,
 and the standards for delisting are top
 strinjjent; delisting requites     ,      ;
 denvmstiating that the substance^'will
 not"|;au{ie death, injury, or
 enviilbnmental harm.
   EPA beh'eves the acute toxicity
 criteiia for listing toxics, as well as the
 volatility arid accident history, provide
 a valild basis for identification of
 chemicalis that pose hazards to the       •
.conn^unity in case of acute exposures
resulting from an accidental-release and
is reti|iriiiig these criteria for petition
review. The Agency is also retaining the
selecition criteria for h'stirig flammables
and explcisiyes. EPA agrees that the
•petition risquiremerits for delisting may
be too stringent and will delete         •
substances from the list if it:can be
deteKpined that the substance, in case
of an laccidental release, "is not known
or anljicipated to"  cause death, injury, or
serious" adverse effects to human health
or the| environment.
  Onis commenter said the decision not
to accept additional petitions unless

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4490      Federal  Register / Vol. 59, No*  20 /Monday, January. 31,  1994 /Rules and Regulations
now data become available should be
modified so that petitions that present
significant data not previously
considered (whether or not the data are
new) can be accepted. The petition
process provides that when a petition is
received, EPA will publish a notice in
the Federal Register requesting
additional, pertinent scientific
information that was not identified by
the petitioner. Interested parties will
have the opportunity to present
significant data not included in the
petition. Therefore, EPA believes it is
appropriate to accept additional
petitions on a substance only if new
data become available.
  Another conunenter said the 18-
month period proposed for review of
petitions should be shortened to six
months. EPA believes the 18-month
review period is not excessive for
carrying out a thorough review of the
petition and any public comments and
publishing a decision concerning the
petition. Denials shall be published in
the Federal Register within 18 months
of the Agency receiving the petition; for
petitions granted, the Agency will
publish a proposed new listing within
18 months.
D. Definitions
  Section 68.3 of the regulation sets
forth the definitions that will apply to
all regulations published under section
112(r). Some of the terms used in other
parts of the CAA are also applicable to
section 112(r). In addition, a number of
terms new to the CAA, resulting from
the implementation of section 112(r),
aro defined in section 68.3 for purposes
of all accidental release prevention
regulations. These definitions include
terms necessary to communicate
effectively the new regulatory
requirements.
  Accidental .Re/ease: The definition
proposed for accidental release has been
taken directly from the legislative
language. Several commenters, however,
thought it appropriate that the Agency
clarify this definition to better focus on
EPA's intent through this regulation.
Several commenters submitted that the
definition of accidental release should
be clarified not to include routine
emissions to the environment. The
Agency believes that the definition is
clear in specifying that and accidental
release is an "unanticipated emission"
of a regulated substance and that this
would not include routine emissions. .
Several commenters also had concerns
regarding the inclusion of the term
"other extremely hazardous substances"
in the definition of accidental release.
This term has also been taken directly
from the legislative language and the
 Agency believes it to be an important.
 component of this definition. Under
 section 112(r)(l) the owners and
 operators of stationary sources have a
 duty to initiate specific activities to
 prevent and mitigate accidental releases
 of any regulated substance under
 112(r)(3), or any other extremely
 hazardous substance.
   Process: There were a number of
 comments related to EPA's definition of
 process. The proposed definition was
 consistent with OSHA's definition of
 process under their PSM standard, and
 included any activity involving a
 regulated substance including any use,
 storage, manufacturing, handling, or on-
 site movement of such substances, of
 combination of these activities. Any
 group of vessels that is interconnected,'
 or separate vessels that are located such
 that a regulated substance .could be
 involved in a potential release, were
 proposed to be considered a single
 process. Because of the need to maintain
 as much consistency as possible with  - :
 OSHA, EPA is retaining this definition
 and is providing, in this preamble, some
 clarification prompted by comments
 submitted on this issue.
   Many commenters. argued that the  •
 proposed definition included terms that
 were not clear, such as interconnected
 vessels and single processes. The
 commenters indicated, for example, that
 in some cases vessels may be connected
 in indirect ways and still present a low
 probability that they could be involved
 in a single release. The Agency believes
 that this was already accounted for .
 through the'proposed "definition of
 process. To serve as clarification,
, interconnected vessels that could be
 involved in a single release would'
 include vessels physically connected so
 that an event could lead to an accidental
 release involving all these vessels at one
 tune. The Agency still believes that the
 facility is responsible in accounting for
 any quantity o'f et regulated substance
 that could potentially be released from
 one or more vessels, whether these are
 connected or not.  '          '   '•"•:.
   Stationary source: Several
 commenters requested clarification •:-
 regarding pipelines and whether listed
 flammable substances in pipeline
 transfer stations would be covered by
 the rule under the stationary source
 definition. Other commenters had
 questions regarding the inclusion in this
 definition of transportation containers
 not under active shipping orders.  The
 Agency is clarifying the definition of
 stationary source. For purposes of
 regulations under section 112(r), the
 term stationary source does not apply to
 .transportation conditions, which would
 include.storage incident to such   •-*''.
transportation, of any 112(r) regulated
substance. Pipelines, transfer stations,
and other activities already covered ,
under DOT as transportation of
hazardous substances by pipeline, or
incident to such transportation, under  ;
49 CFR parts 192, 193 and 195 would
not be covered. Transportation       .
containers that are not under active
shipping papers are not considered by
EPA to be storage incident to
transportation; the Agency considers the
definition of stationary source to
include such containers.
E.Exemptions   '      """.'.'..'  ','- .
  The Agency is retaining the proposed :
exemption from this part  for ammonia
used as an agricultural nutrient, when
held by farmers. This exemption was
authorized by statute, and it was also
generally supported by commenters.  '
  A number of commenters Suggested
that an exemption should be added for
natural gas,  mainly because of other
existing regulations. As, discussed
previously in this preamble, EPA's ,
listing of a substance is based on the .
demonstrated or potential effects in the
event of an accidental release. Existing
regulations may be targeted to reduce a .. -"
potential release, or the effects of a
release, but  do not.negate the  hazards
presented by the substances regulated.
Existing requirements under other
regulations, standards, or recommended
practices are to be accounted for though
the requirements .of the risk
management program and any other
prevention regulations under  section
                              "
F. Scope
•  An issue of concern to a number of
commenters were the general duty
requirements under section-112(r)(l).
Generally, commenters voiced some
confusion regarding what the
requirements would be, and particularly
about which substances would be
included. Because of similarities with
OSHA's general duty clause,
commenters expressed the need for EPA
to develop guidance along the OSHA
Field Operations Manual to assist
facilities in evaluating their compliance
with these requirements.
  The CAA identified the following
activities as part of the general duty
requirements: Identification of hazards
which may result from an accidental
release using appropriate hazard
assessment techniques,,designing and  .
maintaining a safe facility taking such
steps as necessary to prevent accidental
releases, and actions which minimize
the consequences of an accidental
release once it' has occurred.-, Section
112(r)(l) specifically indicates that  the
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              Federal  Register / Vol. 59, No.: 20 /Monday, January
                                                        Regulations   ,  ,4431
 " general duty provision applies in the
   same manner and to the same extent as
   OSHA's general duty clause under
   section 654, title 29 of the U.S. Code.
   The Agency is investigating the
   relationship betwee.n requirements
   under section 112(r) and OSHA's
   general duty provisions.      •".'•
     Comments were also received on the
   separate issuance of the list and
   thresholds rule and the risk
   management program rule. The  -     /;
 ,  comments'focused on the difficulties for
   the regulated community to evaluate
   and comment c-n the full impact of the
   list and thresholds without specific
  • information on the accident prevention
   requirements. The Agency agrees that
   the separation of these rules  does, not
   allow the regulated .community the
   optimum opportunity to commentori  •
   the proposed regulation. While the
  Agency recognizes that the two rules
  comprise a single program, the statute  v
  allows for proposal and promulgation of
  the list and thresholds rule prior to the
  proposal and promulgation of the
  section 112(r)(7) rule. Because EPA's
  duty .to publish the list and thresholds
  rale arose before the duty to publish the
  risk management program rule, the
  Agency was obligated to publish the
  proposed list and thresholds rule before
  the section 112(r)(7)(B) proposed rule
  was publishable. The Agency has just
  published a proposed notice for the
  prevention requirements applicable to
  facilities having the listed substances
  above the threshold quantities (Risk
  Management Programs for Chemical  ^
  Accidental Release Prevention, 58 FR
  54190, October 20,1993). The comment
  period for the risk management program
  mle will be  open at the time this rale
  is finalized. This will give commenters
  the opportunity to comment on the risk
  management program with the
  knowledge of what substances are
  covered.              .
 V. Summary of Provisions of .the Fizaal
 Rule  <.       • :••  ,     •;.•-•...-.-...

   EPA is adding part 68 to title 40 of the
 Code of Federal Regulations, including
 the.list of regulated substances and
 threshold quantities, as well as the
• requirements for the petition process to
 add regulated substances to the list or to
 delete regulated substances from the
 list.-   ;    •••-- '•;-  .-•• :•/.••;••';..  ... >;
   Section 68.1 establishes the scope of
 the Part 68 chemical accident
 prevention provisions.
   Section 68.3 establishes definitions
 applicable to all Part 68 regulations.
   Section 68.100 establishes the
 purpose of the subpart as the
 designation of regulated substances and
 their threshold quantities, and '.
   establishment of the requirements for
   petitions to add substances or delete
   substances from the list.
    .Section 68.115 (proposed §68.5)
   establishes the procedures to determine
   whether a threshold quantity of a
   regulated substance is present at a
   stationary source. Specific exemptions
   to the threshold determination
   procedure are also included for mixture
   concentrations, articles, and certain uses
   and activities.
    The final rule includes several
   exemptions for mixtures that have been
   revised from the proposed rule. These
-   are:  :   -":•-.   "•., ',."•-   '  •' '".':  .•
    (1) For toxic substances present hi a
  mixture qr solution  at a concentration of
   one percent or greater by weight, the
  facility has the option of demonstrating
  that the partial pressure  of the regulated
  substance in the solution under any or
  all storage or handling conditions is less
  than 10 mm Hg; in this case, the
  quantity of the regulated substance in
  the mixture in the portion-pf the process
  with a partial pressure of less than 10
- mm Hg would be exempt from threshold
  determination;  /  -  \    :
    (2) Mixtures containing regulated
  flammable substances are exempt from
  threshold,determination  if the facility
  demonstrates that the mixture itself
  does not meet the criteria for
  flammability (flash point below 73°F
  (22.8°C) and boiling point below 100°F
  (37.8°C);and
    (3) Mixtures of Division 1.1
  explosives listed in 49 CFR 172.101 and
  other explosives need not be considered
  when,detennining whether a threshold
  quantity is present, provided that the
  mixture is intended to be intentionally
  released (i.e., a non-accidental  release) .
  in a manner consistent with DOT and
 BATF'regulations.
   Section'68.120 specifies the
 requirements for petitions to the Agency
 to add substances to the list, and to
 delete substances from the list: Petition  '
 requirements have been modified
 slightly to read that a substance may be
 deleted from the list if adequate data are
 available to determine that the    ~ .
 substance, in the case of an accidental
 release, is "unlikely to cause" (rather
 than "will not cause") death, injury, or
 serious adverse effects to human health
 or the environment.             -
   Section 68.125 exempts ammonia
used as an agricultural nutrient when
held by a fanner.         ,         ,   ,
   Section 68.130 establishes the list of
regulated substances, including a list of
toxic substances, a list of flammable
substances, and a h'st criterion'for
commercial high explosives.;ThiS
section also establishes the threshold
quantities for all Hsted substances.    "
     The final rule includes several
   changes to the proposed list and
   thresholds, Eighteen substances, with
   va:por pressures below 10 mm Hg, have
   be^h deleted from the proposed list of
   to:jdc substances, and one substance
   (vinyl chloride) has been moved from
   thiplist of toxic substances to the list of
   flaimmable substances. One substance,
   methyl bromide, has been deleted
   because it is listed under Title VI of the
   C/LA. Four substances on the proposed '
 .  list, included partly because of their
   accident history, have been deleted
   wliale another* oleum, has been
   specifically h'sted. The final list
   contains 77 toxic substances.  .
   Concentration ^cut-off levelshave been
   specified for solutions of two additional
   substances, hydrogen fluoride and nitric
   acid. The concentration cut-off level has
   be
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4492      Federal Register  /  Vol. 59, No. 20  / Monday, January 31, 1994 / Rules, and Regulations
action". Even though the list and
thresholds rule, by itself, imposes no
cost on facilities, the cost impact of the
list and thresholds derives from
compliance with the risk management
program regulations and other
reasonable regulations, which are
triggered by the presence of a regulated
substance above its threshold quantity.
Ths annual effect on the economy for
the accidental release prevention
regulations that will be triggered by this
rulo is expected to exceed $100 million.
As such, this action is submitted to
OMB for review as part of a larger
accidental release prevention program.
Changes made in response to OMB
suggestions or recommendations will be
documented in the public record.
  Tho Agency developed a draft
Regulatory Impacts  Analysis (RIA) for
tha proposed rule that considered the
cost for the accidental release
prevention program envisioned under
section 112(r); this draft RIA includes
tha list and'thresholds and the risk
management program requirements. The
list rule, by itself, imposes only very
minimal costs associated with  the
petition requirements for additions to,
and deletions from, the list and for the
documentation of mixtures; the majority
of costs relate to actions that facilities
with listed chemicals must undertake as
a result of the risk management program
rule.
   The requirements under the OSHA
Process Safety Management Standard,
which parallels the EPA risk
management planning requirements,
have now been in place for some time,
and information is becoming available
on the costs to facilities working to
comply with OSHA. An addendum to
the draft RIA was developed for the
 proposed risk management program rule
to reflect public comments and the new
 information. The Agency estimate of the
 universe of facilities covered by the
 final list and thresholds rule has since
 been revised. EPA now estimates that
 approximately 118,000 facilities will be
 covered by the final list and thresholds
 rule. The distribution of facilities
 covered includes 11,000 manufacturers
 and 107,000 non-manufacturers (i.e.,
 refineries; public chinking water and
 waste treatment systems; cold storage
 facilities; wholesalers; agricultural
 retailers; service industry facilities;
 private utilities; propane retailers,
 propane users, explosives
 manufacturers, and gas extraction ana
 processing facilities). The average
 number of regulated substances per
 facility varies from one for cold storage
 facilities to six for highly complex
 manufacturing facilities.
  EPA estimates that the petition
process under this rulemaking will cost
a facility submitting a petition an
average of $5,000.'EPA estimates that
there will be 11 petitions a year. EPA
anticipates that the cost to the Federal
government for processing and
reviewing the petitions will be
approximately equal to the cost to
facilities for filing a petition. The total
annual cost is estimated to be~$110,000
($5,000x2x11 petitions).

B. Regulatory Flexibility Act  ,
 pursuant to the Regulatory Flexibility
Act of 1980, 5 U.S.C. 601 et seq., when
an agency publishes a notice of
rulemaking, for a rule that will have a
significant effect on a: substantial
number of small entities, the agency
must prepare and make available for
public comment a regulatory flexibility
analysis that considers the effect of the .
rule on small entities (i.e., small '
businesses, small organizations, and
small governmental jurisdictions).
   The list rule, by itself, imposes only .
very minimal costs associated with the
petition requirements for additions to,
and deletions from, the list and for the
documentation of mixtures; the majority
of costs relate to actions that facilities
with listed chemicals must undertake as
a result of the risk management program
rule. The risk management program
regulation was proposed by EPA on
October 20,1993 (58 FR 54190); a
discussion of the impacts on small
entities is included on page 54212. The
initial Regulatory Flexibility Analysis is
contained in the combined economic
analysis entitled Regulatory Impact
Analysis in Support of Listing Regulated
 Substances and Thresholds and
Mandating Risk Management Programs
"for Chemical Accident Prevention, as
Required by Section 112(r) of the CAA,
 available in the .docket. A revised.
 economic analysis will be developed in
 conjunction with the final risk
 management program regulation.
 C. Paperwork Reduction Act
   The information collection
 requirements contained in this rule have
 been approved by the Office of
 Management and Budget (OMB) under
 the provisions of the Paperwork
 Reduction Act, 44 U.S.C. 3501 et seq.
 and have been assigned control number
 2050-0127.                 ,
   Public reporting for this collection of
 information in the petition process is   :
 estimated to be approximately 138   ,
 hours per response, including time for
 reviewing instructions, searching
 existing data sources, gathering and
 maintaining the data needed, and
 completing and reviewing the collection
 of information. EPA estimates that there
 will be 11 petitions a year. The total
 annual burden is estimated to be 1,518   '.
 hours (138 hours x 11 petitions).
   Send comments regarding the burden
 estimate or any other aspect of this,
 collection of information, including
 suggestions for reducing the burden, to:
  Chief, Information Policy Branch, PM-223,  :
 U,S., Environmental Protection Agency, 401
 M St. SW., Washington, DC.20460; and to the
 Office of Information and Regulatory Affairs, '
 Office of Management and Budget,
^Washington, DC 20503, marked "Attention:
 Desk Officer for EPA."

 D. Display of OMB Control Numbers

   EPA is also amending the table of
 currently approved information
 collection  request (IGR) control numbers
 issued by OMB-for various regulations.
. This amendment updates the table to
 accurately display those information
 requirements contained in this final
 rule. This  display of the OMB control
 number and its subsequent codification'
 .in the Code of Federal Regulations .
 satisfies the requirements of the -    •
 Paperwork Reduction Act (44 U.S.C.
 3501et seq.) and OMB's implementing
 regulations at 5 CFR part 13201
   The ICR was previously subject,to
 public notice and comment prior to  „_
 OMB approval. As a result, EPA finds
 that there  is "good cause" under section
 553(b)(B) of the Administrative
 Procedure Act (5 U.S.C. 553(b)(B)) to
 amend this table without prior notice
 and'comment. Due to the technical
 nature of the table, further notice and .
 comment  would be unnecessary. For the'
 same reasons, EPA also finds that there
 is good cause under 5 U.S.C. 553(d)(3).

 L,ist of Subjects       .

 40 CFR Part 9  .     •

   . Environmental protection, paperwork
 reduction act.           •••,'_•''..••

 40 CFR Part 68

   Environmental protection, Chemicals,
 Chemical accident prevention, Clean
 Air Act, Extremely hazardous
 substances, Intergovernmental relations;
 Hazardous substances, Reporting and
 Recordkeeping requirements. "
   Dated: January 14,1994.
 Carol M. Browner,
 Administrator.                      -,
   For the reasons set out in the
 preamble, title  40, chapter I, subchapter
 A, part 9 of the Code of Federal
 Regulations is amended, and title 40,
 chapter I, subchapter C, part 68 ,of the   -
 Code of Federal Regulations is added, as
 set forthbelbw:  ."'....,.'.  , •  .-,  .- ;',-<.-_.;.._

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             .Federal :RegisterV:Vol. 59, No. J20  I  Monday.  January 31, 1994^ Rules and Regulations
                                                                                    4493
  PART S—OMB APPROVALS UNDER
  THE PAPERWORK REDUCTION ACT

    1. The authority citation for part 9
  continues to read as follows:       ,

    Authority: 7 U.S.C. 135 et seq., 136-136y;
  15 U.S.C. 2001, 2003, 2005,"2006, 2601-2671;
  21 U.S.C. 331j, 346a, 348; 31 U.S.C. 9701; 33 '
  U.S.G. 1251 et seqi, 1311,1313d, 1314,1321
  1326,1330, 1344,1345 (d) and (e), 1361; E.O.
  11735,;38 FR 21243, 3 CFR, 1971-1975  ,
  Comp. p, 973; 42 U.S.C. 241, 242b, 243, 246,
  300f, 300g, 300g-l, 3bOg-2,.300g-3, 300g-4,
  300g-5, 300g-6, 300j-l,-300j-2, 300J-3, 300J-
  4, 300J-9,1857 et seq., 6901-^3992^ 7401-
  7671q, 7542,"9601-9657,11023,11048. '

    2. Section.9.1 is amended by adding
  the new entry with a new heading to the
  table to read as follows:

  §9.1 OMB approvals under the Paperwork
  Reduction Act.                      :
        40 CFR citation.:
OMB control
    No.
 Chemical Accident Prevention:
   Provisions:- •
  , 68.120 (a), (e), and (g) .........  2050-0127
   3. Part 68 is added to read as follows:

 PART 68—CHEMSCAL ACCIDEMT
 PREVENTION PROVISIONS

 Subpart A—General
 Sec.    '-,''.  _ -_'• ... •: .   -' •;.•-•  •-.:-.
 68;l  Scope.              •••".   :  ;-,
 68.3  Definitions.  ' '       "  .

 Subpart B—Risk Management Plari
 Requirements [Reserved]
 Subpart C—•Regulated Substances for
 Accidental Release Prevention
 68.100 ' Purpose.
 68.115  Threshold determination."      ;•
 68.120  Petition process.             '••
 68". 125  Exemptions.    " '
 68.130  List of substances;         '•-.'••
  Authority: 42.U.S.C. 7412(r),76br.  .

 Subpart A—General

 §68.1  Scope.
  This Part sets forth the list of
 regulated substances and thresholds, the
 petition process for adding or deleting
 substances to the list of regulated  :    .
 substances, the requirements for owners.
 or operators of stationary sources
 concerning the prevention of accidental
 releases, and the State accidental release
 prevention programs approved under   :
 section ,112(r). The list of substances,
threshold quantities; and accident
prevention regulations promulgated   '.:';'
under this part do not limit in any way
  the general duty provisions under
  section 112(r)(l).           '

  §68.3  Definitions,
    Eor the purposes of,this Part:
    Accidental release means an     •';•-'•
  unanticipated emission of a regulated
  substance or other extremely hazardous
  substance into the ambient air from a
  stationary source.       ":
    Administrator means the
  administrator of the U.S. Environmental
  Protection Agency.                    :
    Article means a manufactured item, as
  defined under 29 CFR 1910.120p(b), that
  is formed to a specific shape or design
  during manufacture,.that has eiid use
  functions dependent hi whole' or in part.
  upon the shape or design during end
  use,.and that does not release or
  otherwise result in exposure .to a
  regulated substance under normal •"-'.'.'-
  conditions of processing and use.    -
    CAS means the Chemical Abstracts
  Service.  : -           ••     •
    DOrmeans the United States
  Department =6f Transportation.
    Process means any .activity involving
  a regulated substance including any use,
  storage, manufacturing; handling, or on-
  site movement of .suchsubstances, or
  combination of these, activities. For the
  purposes of this definition, any group  of
 .vessels that are interconnected; or
.  separate vessels that are located such
  that a regulated substance could be    .'-
  involved in a potential release, shall be
  considered a single process.
  . Regulated substance is any substance
 .listed pursuant to section 112(r)(3) of  '
 the Clean Ah-Act as amended, in
 §68.130. „    >•
   Stationary source mearis any
 buildings, structures, equipment,   ,"':
 installations> or substance.emitting
 stationary activities which belong to the
 same industrial group, which are
 located on one or more contiguous
 properties/which are under the.coritrol  ,
 of the same person (or persons under
 common control), and from which an
 accidental release may occur. A
 stationary source includes
 transportation containers that are ho •
 longer mider active shipping papers arid
 transportation containers that are
 connected to equipment  at the
 stationary source for the purposes of    •
 temporary storage, loading, or           :
 unloading. The term stationary source
 does not apply to transportation,
 including the storage incident to
 transportation, of any regulated
 substance or any  other extremely
 hazardous substance under the
 provisions of this part, provided that
 such transportation is regulated under
 49 CFR parts 192,193, or 195.
Properties shall not be considered
                                                  :  contiguous solely because of a railroad
                                                    o!r gas pipeline right-of-way.  '
                                                    ^Threshold quantity means the
                                                    qjiianflty specified for regulated
                                                  • . Substances pursuant to section 112(r)(5)
                                                    of the Clean Air Act as amended, listed
                                                    m 1 68.130 and determined to be •  ;   '
                                                    Resent at a stationary source as   -
                                                  •  specified in §«8.115 of this Part:
                                                    '.Kfeil^.means any reactor, tank', drum,
                                                    bprrel, cylinder, vat, kettle, boiler, pipe,
                                                       , pr other container. .-'-•
  ^|ubpart B— Risk Management Plan
  R|equirements [Reserved]

  Subpart C— Regulated Substances for
  Accidental Release Prevention
  § B8,KK) Purpose. -
 •  liThissubpart designates substances to
  -b(3 listed under section 112(r)(3), (4),
  aiid (5) of the jClean Air Act, as
  amended, identifies their threshold-
  qjiantities; and establishes the   ' .;
  re|quireinents for petitioning to addTor
  dijlete substances from the list.
 .  •&":.•- ---;' •-...-: -y ••;-."- ;   -.  -  ".  ' •  v-.-/.  "
  §158.1 1 5  Threshold determihation.
  ,n(a) A- threshold quantity of a regulated
  substance listed in § 68:130 is present at
  a istationary source if the total quantity
  of|ffie regulated substance, contained in
  a ^process exceeds the threshold.
   j(b) For the purposes of determining
  whether more than a threshold quantity "
  °f[S^S^lated substance is present at th&
  st|ti6ri^ry source, iihe following
  exemptions apply:   '            ,.
   ti) Concentrations, of a regulated toxic
 substance in a mixture. If a regulated
 suhstattce is present in a mixture and- •   •
 this .concentration of the substance is
 below one percent by weight of the
 milxture, the amount of the substance in
 this mticture need not be considered
 wl^en determining whether more than a
 thireshpld quantity is present at the
 staitiqnary source. Except for oleum,
 toluene 2,4-diispcyanate, toluene 2,6- ,
 dii §t)cjranate, and toluene diisocyanate
 {uiispecified isomer), if the
 coiicentration of the regulated substance.
 i?1 ^e mixture is one percent or greater
 by [Weight, but the owner.or operator can
 demonstrate that the partial pressure of
 thej; regulated substance in the mixture '•
: (solution) under handling or storage  .
 conjditions in any portion of the process
 is Jess than 10 millimeters of mercury
 (mm Hg), the amount of the substance
 in lie mixture in that portion of the
 prcjeess need hot be considered when
 determining whether more than a
 threshold quantity is present at the
 staljiphary source. The owner or operatoi
 shall dcicuinent this partial pressure  ,
             or esthriate.  :    '.'

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 4494     Federal Register / Vol.  59, No. 20  /  Monday, January•51, 1994 /Rules. and Regulations^
   (2) Concentrations of a regulated
 flammable substance in a mixture. If a
 regulated substance is present in a
 mixture and the concentration of the
 substance !s below one percent by
 weight of the mixture, the mixture need
 not be considered when determining
 whether more than a threshold quantity
 of the regulated substance is present at
 tho stationary source. If the
 concentration of the regulated substance
 in the mixture is one percent or greater
 by weight, then, for purposes of
 determining whether more than a
 threshold quantity is present at the
 stationary source, the entire weight  of
 the mixture shall be treated as the
• regulated substance unless the owner or
 operator can demonstrate that the
 mixture itself does not meet the criteria
 for flammability of flash point below
 73SF (22.8°C) and boiling point below
 100°F (37.8*C). The owner or operator
 shall document these flash point and
 boiling point measurements or
 estimates.
   (3j Concentrations of a regulated'
 explosive substance in a mixture.
 Mixtures of Pivision 1.1 explosives
 listed in 49 CFR 172.101 (Hazardous
 Materials Table) and other explosives
 need not be included when determining
 whether a threshold quantity is present
 in a process, when the mixture is
 intended to be used on-site in a non-
 acddental release in a manner
 consistent with applicable BATF
 regulations. Other mixtures of Division
 1.1 explosives listed in 49 'CFR 172.101
 and other explosives shall be included
 in determining whether more than a
 threshold quantity is present in a
 process if such mixtures would be
 treated as Division 1.1 explosives under
 49 CFR Parts 172 and 173.
    (4) Articles. Regulated substances
 contained in articles need not be
 considered when determining whether
 more than a threshold quantity is
 present at the stationary source.
    (5) Uses. Regulated substances, when
 in use for the following purposes, need
 not be Included in determining whether
 more than a threshold quantity is
 present at the stationary source:
    (i) Use as a structural component of
 the stationary source;
    (ii) Usa of products for routine
 Janitorial maintenance;
    (lii)  Use by employees of foods, drugs,
 cosmetics, or other personal items
 containing the regulated substance; and
    (iv) Use of regulated substances
 present in process water or non^contact
 cooling water as drawn from the
 environment or municipal sources, or
 use of regulated substances present in
 air used either as compressed air or as
 part of combustion.
   (6) Activities in Laboratories. If a
 regulated substance is manufactured,
 processed, or used in a laboratory at a
 stationary source under the supervision
 of a technically qualified individual as
 defined in § 720.3(ee) of this chapter,   ;
 the quantity of the substance need not
 be considered in determining whether a
 threshold quantity is present. This
 exemption does not apply to:
   .(i) Specialty chemical production;
   (ii) Manufacture, processing, or use of
 substances in pilot plant scale
 operations; and               '
   (iii) Activities conducted outside the
 laboratory.

 §68.120  Petition process.
   (a) Any person may petition the
 Administrator to modify, by addition or
 deletion, the list of regulated substances
 identified in § 68.13ff. Based on the
 information presented by the petitioner,
 the Administrator may grant or deny a
 petition.         •           ••
   (b) A substance may be added to the •
• list if, in the case of an accidental
 release, it is known to cause or may be
 reasonably anticipated to cause death,
 injury, or serious adverse effects to
 human health or the environment.
   (c) A substance may be deleted from  ,
 the list if adequate data on the health
 and environmental effects of the
 substance are available to determine
 that the substance, in the case of an
 accidental release, is not known to
 cause and may not be reasonably
 anticipated to cause death, injury, or
 serious adverse effects to human health
 or the environment.
    (d) No substance for which a national
 primary ambient air quality standard
 has been established shall be added to
 the list. No substance regulated under
 Title VI of the Clean Air Act, as
 amended, shall be added to the list.
    (e) The burdenofproofison the
 petitioner to demonstrate that the
 criteria for addition and deletion are
 met. A petition will be denied if this
 demonstration is not made.
    (f) The Administrator will not accept
 additional petitions on the same ..
 substance following publication of a
 final notice of the decision to grant or
 deny a petition, unless new data
 becomes available that could
 significantly affect the basis for the
 decision.
    (g) Petitions to modify.the list of .
 regulated substances must contain the
 following:
    (1) Name and address of the petitioner
 and a brief description of the
 organization^) that the petitioner
 represents, if applicable;
  (2) Name, address, and telephone
number of a contact person for the   .
petition;               ••        .
  (3) Common chemical name(s),
common synpnym(s), Chemical
Abstracts Service number, and chemical
formula and structure;   (
  (4) Action requested (add or delete a
substance);
  (5) Rationale supporting the
petitioner's position; that is, how the
substance meets the criteria for addition
and deletion. A short summary of the
rationale must be submitted along with
a more detailed narrative; and   ,
  (6) Supporting data; that is,1he
petition must include sufficient
information to scientifically support the
request to modify the list. Such
information shall include:     '
  (i) A list of all support documents;
  (ii) Documentation of literature
searches conducted, including, but not
, limited to, identification of the
database(s) searched, the search
strategy, date's covered, and printed
results;               -   ,  .   .   '
   (iii) Effects data (animal^ human, and
environmental test  data) indicating the
potential for death, injury, or serious
adverse human and environmental
impacts from acute exposure  following
an accidental release; printed copies of
the data sources, in English, should be
provided; and,
   (iv)  Exposure  data or previous
accident history data, indicating  the
potential for serious adverse human
health or environmental effects from an
 accidental release. These data may  ;
 include, but.are not limited to, physical
 and chemical properties of the
 substance, such as vapor pressure;
 modeling results, including data and '  ,
 assumptions used and model ,
 documentation; and historical accident
 data, citing data sources,  •"         .
   (h) Within 18 months of receipt of a
 petition, the Administrator shall publish
 in the Federal Register a notice either
 denying the petition or granting the
 petition and proposing a listing.

 §68.125 Exemptions.   .
   Agricultural nutrients. Ammonia used
 as an  agricultural nutrient, when held
 by farmers, is exempt from all
 provisions of this part.

 §63.130 List of substances.
   (a) Explosives listed by DOT as
 Division 1.1 in 49 CFR 172.101 are
 covered under section 112(r) of the
 Clean Air Act. The threshold quantity
 for explosives is 5,000 pounds.
   (b) Regulated toxic and flammable
 substances under section 112(r) of the •
 Clean Air Act are the substances listed
 in Tables 1, 2, 3, and 4. Threshold

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qlerd KBjister / Vol.  59, No.  20  / Monday, Jaman,  31. 1994 \, Mes  8nd Regulations
                                                                           ~"
                                                                                                                                4495
                   TO §ee,30.-LlsT
                                                regulated substances are explained in
                                                the notes tp the list.
                                       TOX,

                                  [Alphabetical Order— 77 Substances]
                '
    Acrolein [2-Propenafl	
    Acrylonitrile [2-Propenenitrile] .."..""!.."'"
    Acrylyl chloride [2-Propenoyl chloride]'.".                                 	
    Allyl alcohol [2-Propen4ol]	           	'	
    Aliylamine [2-Propen-)-amine]  	'".'.'""".	•••-
    Ammonia (anhydrous) ..:	.".."	"	•	
    Ammonia (cone 20% or greater)"	*	•	
    Arsenous trichloride	      	
    Arsine	„	™_"	•"•	
    Boron trichloride [Borane, tricnloro-]	
    Boron trifluoride [Borane, trifluoro-]    	
   SrS^"!.!.!!.1^^ Wi
-------
4496     Federal Register / Vol. 59. No. 20 / Monday. January  31. 1994 / Rules  and Regulations	^

     TABLE 1 TO §68.130.—LIST OF REGULATED Toxic SUBSTANCES AND THRESHOLD QUANTITIES FOR ACCIDENTAL
                                        RELEASE PREVENTION—Continued
                                          [Alphabetical Order—77 Substances!
Chemical name
ProplontWIe [Propanenitrile] 	 «• 	 • 	 •••• 	 > 	 — — ~ — »— -•>-• 	 -•-•••
Propyl chloroformata JCarbonochloridkJ add, propylesterj 	 ....... 	 ••••• — • 	 • 	
PropytonolmJns [AzkhSne, 2-methyH ~ — .......... 	 	 — .......................
Propytena oxkte [Oxlrane, methyl-] .__™.....~. 	 	 	 	 	 — 	 	 	
Sulfur tfoxJda (anhydrous) .. 	 • 	 • 	 "••••••
Sulfur tetrafkKxkte [Sulfur fhjortde (aM). ti -4j-j — . 	 	 •••/ 	
Sulfur trtoxkte 	 	 	 •- 	 • 	 • 	 r"" 	 "
Telxamethyttead [Plurnbane. tetramethyH 	 	 	 	 ?~ 	 	 	 <
TetranJtrornetnarm [Methane, tetran'rtro-] . 	 	 — • 	 — — ->••- 	 ? 	 ..............
TKartom tatracMorlde [Titanium chloride (T1CI4> fJ-4H • — rrj™-"^"" 	 "" "' — ' — ' — 	 —
TokJ&na 2,4-dIsocyanate [Benzefte, 2,4-dilsocyanato-1 -methyl-]1 •••• — • — — — •• — «—— • —
Toluene 2,6-dBsocyanata [Benzene, l,3-diisocyanato-2-methyl-]i — •"":"""" 	 """"" 	 ""
Totuorta dtisocyanata (unspecified isomer) [Benzene, 1,3-dnsocyanatomethyH1 	 --• — - 	 	 — ••
Trhnothyhshtorosilana [Silane, chtorotrimethyH ... — .... — • 	 « — • — • — •• — •••• •••
vinyl acetate monomer [Acetic add ethenyl ester] 	 	 •— 	 	 — — ••• — - -—
CAS No.
107-12-0
109-61-5
75-55-8
75-56-9
7446-09-5
7783-60-0
7446-11-9
75-74-1
, 509-14-8
7550-45-0
' 584-84-9
91^08-7
26471^62-5
75-77-4
108-05-4
Threshold
quantity
(Ibs)
10,000
* 15iOOO
10,000
-10,000
5,000
, 2,500
10,000
10,000
10,000
2,500
10,000
10,000
10,000
10,000
15,000
Basis for
listing
b -
b
b
b .
a,b
b
a, b
b
b
b
a ' •
a
a '• . • ' ;•"•
b
b
   iTha mixture exemption In §68.115(b)(1) does not apply to the substance.
   NOTE Basis for Listing:
   a Mandated tor listing by Congress.
   b On EHS list, vapor pressure 10 mmHg or greater.
   c Toxic —
     Toxteilvfof hydfogen chloride, potential to release hydrogen chloride, and hfetorv^ac^"^- .. nt
     Toxlcity of sulfwWoxIde and sulfuric acid, potential to release sulfur trioxide. and history of accidents,

     TABLE 2 TO 568130 —LIST OF REGULATED Toxic SUBSTANCES AND THRESHOLD QUANTITIES FOR
                                              RELEASE PREVENTION
                                          [CAS Number Ofder—77 Substances]
ACCIDENTAL
CAS No.
50-00-0 	
57—14-7 _„„„„„
60-34-4 	
67-66-3 	 -
74-87-3 	
74-90-8 	
74-93-1 	
75-15-0 	
75-21-8 	
75—44-5 ...........
75-55-8 	
75-66-9 	
75-74-1 	 »
75—77—4
75-78-5 « 	
75-79-6 	
78-82-0 	
79-21-0 	
78-22-1 	
9-1-amine] 	 - 	 - 	 ••-» 	 .
Proplonitrne [Propanenitrile] .......i..........~~ 	 - 	 • 	
Actyfonitrile [2-PropenenitriIe] „... 	 ..~. 	 	
Ethylenediamlne[t^-Ethanediamine} 	 . 	 	 	 	 • 	 — ••• 	 — — •• — 	 ......—»•
Ally) alcohol p-Propen-l-oi] „ 	 .._......... 	 	 	 . — - 	 - 	 	 	 ,~~
Chloromethyl methyl ether [Methane, chtoromethoxy-j 	 	 	 ••— — •— 	 •• .-
Vinyl acetate monomer lAcetic acid ethenyl ester] 	 	 	 •• 	 • 	 •— - 	 	
Isopropyl chloroformate [Carbonochloridw actp, i-rneinyiemyi esierj 	 — — • ,
Cyclohexylamlne [Cyctohexanamine] ™... 	 . 	 ••— 	 	 	 	
Propyl chloroformate [Carbonochloridic acw, propyiesierj 	 	 	 	 r —
rUiclii .......................«....«."•»".....?•..•.**.* - i
Piperkfina .™...™™.— ~.~™— .—.-——.—•«——— 	 .....-..— ~. 	 - 	 - 	 .................
CrotonaWehyde, (E)- [2-Butenal, (EH 	 •— 	 - 	 ;.•—"••— -••'•• 	 " 	 ™ 	 -••••— ••••••'••
Methacrylonitrila [2-Propenenitrile, 2-methyH 	 	 — .-- 	 • 	 	 ••"••••• '•-
Threshold
quantity
(Ibs)
15,000
15,000
15,000
20,000
10,000
2,500
10,000
20,000
10,000
500
10,000
10,000
10,000
10,000
. 5,000
5,000
20,000
10,000
5,000
10,000
20,000
5,000
, 10,000
10,000
20,000
20,000
15,000
5,000
15^)00
15,000
15,000
15,000
" 5,000
15..000
. 20,000
' M 0,000
Basis for
listing
b
3 :
b
b
a
a.b
b
b
a.b
a,b
b
b
b
b
b
b
b
b
b
a
b'
b -"•
b
b
b
b
b
b
b
b
b ,
b
b
b • •:.-
b'
b ••; r', •• •

-------
  	w-,*_Jp<,
         Federal Raster /'Vol. 59, No.' 20 / Monday, January 31.  1994 / Rules and Regulations     4497
    TABLE 2 TO §68.l30.-LisT OF REGULATED Toxic SUBSTANCES AND THRESHOLD QUANTITIES FOR ACCIDENTAL
                                   RELEASE PREVENTION—Continued
                                     [CAS Number Order—77 Substances]
CAS No.
302-01-2
353-42-4-... 	 	
506-77-4 .
. 509-14-8 .
542-88-1 .;.......;
556-64-9
-584-84-9
594-42-3
624-83-9
814-68-6 ,
41 7O— SO— 3
7446-09-5
7446-11-9
7550-45-0 '
7637-07 2 ........
7647-01-0 ;..„...
7647-01-0-
7664-39-3
7664-41-7
7664-41-7
7697-37 2 ........
7719^12-2
7726-95-6 ........
7782-41-4 ...-.-;...
7782-^60-5 	 	
7783-06-4 ........
7783-07-5 	 	
7783-60-0 .v......
_7784-34-1.........
7803-51-2 ........
8014-95-7 ...;....
•10025-87-3 ......
10049-04-4 ......
10102-43-9 ......
10294-34-5 ......
13463--39-3 :,...".
13463-40-6 ......
19287-45-7 ......
26471-^2-5 :......
Chemicarnarhe
^
Ethyleneimine [Aziridine] 	
Hydrazihe .: 	 !!!."!!!"!!! 	 ' 	 ' 	 ""." 	 ' 	 ' 	
BorOTWfluoriderompou^
Cyanogen chloride .....„!..... -••-.-. . -.--..- " - '"•"* — "•••••
Tetranitromethane [Methane, tetranitro-j -•"' 	 "" ' "''""""""•"""-•
Chloromethyl ether [Methane oxybis[chloro-] ——............... 	 	 	 j 	 	 ..........,..:.
Methyl thiocyanate rjhiocyanlc acid, methyl es'terj !"'""""""""""""
Toluene 2,4-dnsocyanate [Benzene, 2,4-diisocyanatc-1-methyl-]i
Perchlpromethylmercaptan [Methanesulfenyl chloride, trichlorc-1
Methyl isocyanate [Methane, isocyanato-]
Acryiyl chloride [2-Propenoyl chloride] 	 •"•••••••••"••••••••••,»•..........,.
I Crotonaldehyde [2-Butenal] 	 	 	 	
Sulfur dioxide (anhydrous) ................. . .—•---• 	 	 	 ...
Sulfur trioxide ..........'...„ 	 	 	 ......v...... .:.!]."]!!]!!!!"""""""'
Titanium tetrachloride [Titanium chloride (TiCI4) "(TM)'-i " ' "'"""":"
Boron trifluoride [Borane, trifluoro-] 	 	 	 	 - •".' 	 """""

.........,...vr....j; ;.^; ..,;.;„„;.;:.„:... •
Hydrogen chloride (anhydrous) [Hydrochloric acid] ....... • ,-•---••'";••-"• 	 •• 	 -••
Hydrogen fluoride/Hydrofluoric acid (cone 50% or greater) [Hydrofluoric acid} ' ""'""""'" 	 '""'.'
Ammonia (anhydrous) ........ . • ' - .•> ••.•'•••"•• • 	 — 	 ..........
Ammonia (cone 20% or greater) 	 	 - -. •-.•"•—•—; - 	 	
Nitric acid (cone 80% or greater) ................. —"-•--••---,•-•,—•-• 	 —•;••-•" v;:;"";— ••••••:•••••;
Phosphorus trichloride [Phosphorous trichloride] ..
Bromine 	 	 	 '"•""" 	 """"
Fluorine. 	 ...;..... 	 „. .. . :
Chlorine 	 	 	 	 	 	 	 	 	 ;_.____ •;• ——•••.—;.-.........
Hydrogen sulfide ........;..... ..... •••-••-"-;•"--•• 	 .......v... ....i......
Hydrogen selenide 	 	 	 = ——-—•-• 	 •;• 	
Sulfur tetrafluoride [Sulfur fluoride (SF4), (T-4J-1 -'-
Arsenbus trichloride ' 	 	 	 	 •"""" 	
Arsine 	 	 '"
Phosphine 	 	 .......„....; 	 	 	 ......!"""""""" 	 ———......
Oleum (Fuming Sulfuric acid) [Sulfuric'acid'rmix't'ure"^
Phosphorus oxychloride [Phosphoryl chloride] .
Nitric oxide [Nitrogen oxide (NO)] 	 ..••.»«..»..... 	 	 	 ....
Boron trichloride [Borane, trichlorb-J ,
......... 	 	 ,.... ....^...... 	 .;..

1 ••—""...v .....™....................
.,:„..,,.;....;:- :::::iv::;::"::;;;:
	 • 	 ••*•>>»................-.....

ron, pentacarbonyl- [Iron carbonyl (Fe(eO)5), (TB-5-11)-] . ...............................
N^-lBasi'rfoTLSf''0-'1 '" § 68"1 1 5(b)(1 5 d°6S "Ot ^ to the substance- , ' '
a Mandated for listing by Congress. . *r^~" •
. - b OnEHSIist, vapor pressure 10 mmHg or greater. "'
c Toxic gas.
e Toxicity-of sulfur trioxide and sulfuric acid, potential to release sulfur trioxide, and history of accidents.
Thresholc
quantity
(IDS)
10,000
15,000
15,000
10,000
'10,000
• 1,000
-• 20,000
"•; 10,000
,10)000
'. 10,000
, 5,000
20,000
5,00'0
10,000
,2,500
5,000-
15,000
: .5,000
... 1,000
10,000
20,000
' 15,000
15,000
10,000
1,000
2,500
10,000
-2;500
15,000
1,000
5,000
10,000
5,000
;.i,ooo
10,000
5,000
, .1,000
; 2,500
:' "2.500
10,000
J\ "
Basis.for
listing
crcrq-D-crO Cf o cr o-cr,crer.p) M .CTJB cr.cra) w_os to .do- erm to cr cr.ia. 'cr ni & cr cr o b- cr cr
•••' .. '-"-• .'. ._., ;'. " ' _ ., " •, .."'--, eriy •' er- •; .. o-cr'cr, . ' crcr . •. cr •'' '.;'••'',.'','
- •'-.••'.' -. ,.:. .''...••'' -'••-.'',' ••'..' '•• .' . ' ' '--.• ' ••-'.' ' '•'''-'",', -;
a
^>
TABLE 3 TO §68.130.-L1ST OF REGUUTED FLAMMABLE SUBSTANCES AND THRESHOLD QUANTITIES FOR ACCIDENTAL
                                        RELEASE PREVENTION
                                    [Alphabetical Order—63 Substances]
. Chemicalnarne
Acetylene [Ethyne] 	 •."•«»'"»«"!!.""™!"!!!!!."!!!.'."!"."" 	
Brpmotrifluorethylene [Ethene, bromotrifluoro-1 	 " 	
1 ,3-Butadiene 	 	
Butane 	 	 	 ; 	 •„• 	
1-Butene ..........: 	 	
2-Butene 	 -.-. 	 	
Butene 	 	 	 	
. 2-Butene-cis 	 	 I"."]."!".'" 	
2-Butene-trans [2-Butener(E)j '".'"-. 	
Cartxsn oXysulfide [Carbon oxide sulfide (COS)j . 	 ' 	
'
(DAS No.
75-07-0
I -74-66-2'
. 598-73-2
-106-99-0
106-97-8
106-98-9
107-01-7
25167-67-3
' 590-18-1
624—64—6

Threshold
quantity
(Ibs)
10,000
10,000
10,000
10,000
1 10,000
10,000
10,000
"10,000
10,000'
10,000
" 10,000
Basis for
listing
g
f
f
)
f
f
f
f
f
f
f
;,

-------
4498     Federal Register / Vol. 59, No. 20 / Monday, January 31,  1994: /'Rules and^ Rggulatiofls J ^   -


  TABLE 3 TO §68.130.—LIST OF REGULATED FLAMMABLE SUBSTANCES AND THRESHOLD QUANTITIES FOR ACCIDENTAL
                                     RELEASE PREVENTtONr-Continued
                                       [Alphabetical Order—63 Substances]  "           .
Chemical name ; ,



Cyanogen [Ethanedioitrlle] 	 	 ««. 	 . 	 	 	 .„..,..«....... 	 . 	 . — .....«««. 	 «„...«





Ethano 	 ....... 	 ............. 	 	 	 *...........«....„....
Ethyl acatylooa [1-ButyneJ . .... . ............ 	 - 	 ».;..... 	 	 	 	 — ;« 	 .........

Pthvl rhlwkift tPfhann chJorfWl " 	 	 	 	 «.... 	 .................................
Elmlana lEthenel - 	 	 	 	 	 • 	 	 • 	

P(m;l mAWJwrfnn rPlhnnfithlon 	 	 	 	 	 	 	 -..««.....«....«
PHwl nttrffo IKIrtrnitft nrtrf fiihvl pe-terl 	 •'. 	 .- 	 ...........«....«.«...........*.......«
lJi)l^l>(-LnAr> , . >•>• »• 	 	 	 iiu.





Mcthano 	 « 	 	 	 	 	 .....«....,.^......

^.MolhvUlAi rtARA . fc 	 	 	 .......................
2.Mc\thvH-hirtpno ..'. 	 	 	 	 ..........



1 1.PnnJnH!nonfl .„ . . ... ..« 	 * 	 «... 	 	 »....« 	 	











Trf^htrwftitlliina rsilana frfchloro-1 „« 	 ...„.-.....;....... 	 	 	 - 	 • 	 	







VtnwllHnna fliinrlf irt fPfhflnfl 1 1-difluaro-T . ........; 	 	 	 	
Vinyl methyl ether [Ethene, methoxy-] 	 	 	 - 	 •_• 	 •• 	
CAS No.
7791-21-1
557-98-2
590-21-6
460-19-5
75-19-4
4109-96-0
75-37-6
124-^0-3
463-82-1
74-84-0
107-00-6
75-04-7
75-00-3
74-85-1
60-29-7
75-08-1
109-95-5
1333-74-0
75-28-5
78-78-4
78-79-5
75-51-0
75-29-6
: , 74-82-8
74-89-5
563^45-1
563-46-2
115-10-6
107-31-3
115-11-7
50^-60-9
109-66-0
109-67-1
646-04-8
627-20H3
463-49-0
74-98-6
.11&-07-1
74-99-7
7803-62-5
116-14-3
75-76-^3
10025-78-2
79-38-9
75-50-3
689-QJ^
75-01-4
109-92-2
75-02-5
75-35-4
75-38-7
107-25-5
Threshold
quantity
(Ibs)
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
' 10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
10,000
Basis for
listi'lg
f
g -
9 - ... '
9
g
f
f .-.. ."
f
g
g
g
g .'
f '
f
g .
?
f
g
g
g
g
f* •-. •.
f ;
f
f .
f
g
g ..... •
f
f
aj
g
g. " '"•',
f
  NOTE: Basis for Listing:
  a  Mandated for listing by Congress.                    .       •
  I Flammable gas.                                                 -                :      -   '
  g  Volatile flammable liquid.                                           .                      ,         •

  TABLE 4 TO §68.130.—LIST.OF REGULATED FLAMMABLE SUBSTANCES AND THRESHOLD QUANTITIES FOR AcciDbWA.
                                           RELEASE PREVENTION

                                       [CAS Number Order—63 Substances]       :      .  .
CAS No.
ftfi *vy, *r

' Chemical name
Pihvt p!h«r TPtharifl 1 1'-ox\Ais-l „ 	 	 	 	 	 «...«.....i,,.....«.«*'
Methane 	 	 	 	 	 	 	 	 ~..» 	 - 	 •• 	 —• 	 	 • — «••'
CAS No. "
v- : 60-29-7
74-62-8
Threshold
quantity
(Ibs) •
10,000
10,000
Basis for
listing
g '•'-'
f . .- --

-------
         CAS NO.


     74-84-0
    •74-85-1 .......
     74-86-2	
   -  74-B9-5 ......
     74-98-6 ......
     74-99-7 .......
     75-00-3 .;.......  :
    -75-Q1-4 ;:..:.;.../
    75-02-5 .......;„;.
    75-04-7	;
    75-07-0 ......
    75-08-1 „......""
    75-19-4...........
    75-28-5 ...........
    75-29-6	
   . 75-31-0 .........
.    75-50-3 .;..
    75-76-3 ...........
-    78r78-=4 .;;....  •
".    78^-79-5.....:...
    79-38-9 ,..^.....
    106-97-S .....
    106-98-9 .....
    196-99-0	 '
-   107-00-6....
    107-01-7	...„
    107-25^5 ......
    107-31-3 ..
    109-66-0 ,
    109-67-1 ..
    109-92-2	
-   109-95-5.... "-••
   1.1.5-07-1 ....
   115-10-6	   ..
   115-11-7 ,......"
   116-14-3.....
   124-^0-3	
  -460-19-5 ......
  463-49-0 ....
  463-58-1  ...
  463-^2-T ...
  504-60-9 ....
  557-98-2	
  563-45-1........."
  563-46-2 .....
  590-18-1	
  590-21-6 ....
  598-73-2.....
  624-^4-6 .....
  627-20-3 ....
  646-04-5 ....
 •689-97--4 ....
  1333-74-0 „
 4109-96-0 ....:..
 7791-21-1  :.....
 7803-62-5 .......:
 10025-78-2 .
25167-67-^ '„  .
                                 Chemical name
  Ethane-	 ' • •  . '     ~.~~  '.    . --  -     ..  -.-..-...	•
  Ethylene [Etherle]  .....;....."	-•-—--.......	„....—	........,.,......;.....;
 Acetylene [Ethyne] .:."""""	—-••••--•	~™....~.,.......;......	..._....;
         ,     [Ethane, chlorb-j
 vinyl chloride [Ethene, chlorp-j  •'-.-•        '    	••	-'••>•:• •—•-•••••••••••
 Vinyl fluoride {Ethene, fluoro-]  ""'"	'	•.""•"""•"	•	••••^"•--•.",.......,1...:...
 Ethylamine [Ethanamine]     —--•-•	•-••-	.....;..;;.;....;
 Acetaldehyde	....^....^""""""	•.•"-••.•-••	-	•-•-~..^..^..........:...;..^..
 Ethyl mercaptan [EthanethToJj	f"""""	••-••""---"v--.-.........r..,.....^...-;r..r..;
 Cyclopropane	  """	•"••^••••'	"....-............;.......;
 isobiitane [Propane, 2-m'etnyli	    	••••-...........	
 Isopropyl chloride [Propane, 2-chloroT"""""	'	""'""	'	•—->--4.......
 sopropylamine [2-Propahamine] ....... •"""-•••"	:--•--»	;.:;:-..„.
 Vinylidene chloride [Ethene, 1,1-dichloro-j""""'	;	""""	'""•	—"-•••{-•-
 Difluoroethane [Ethane, 1;1-difluoro-l     --•;-	•	;~---.~........,..:.:.....»r.....
 Vinylidene fluoride [Ethene, 1,1-difIuoro-]'	"'""""	"""	—---"••——••!?••"-
 Tnmethylamine [Methanamine, N, N-dime'th'vlT'r'"	"""" •"•"•"—-v—-"—:t^:,.,
Tetramethylsilane[SHane,tetramethyM        	-•-"------..-...-...	::...;p;,::..
Isopentane [Butane, 2-methyH        ""	""""""""•"••"••	-••;•»-.:.....:.....£	:
teoprene [1,3,-Butadiene, 2-methyH "!i;!;;"!;Z!!I!Z:;Zr"""'"""'""'"""""""'""""T'";"
  1-Butene	-v.....!!""!r'""''"""" ••—•—'••	....:.... ,„... ..:l.....;..........v..J.^7:.
  1,3-Butadiene '-'....;„:„"''""'""'""	v-----»-.r../.....:	v-»:....,..-i.:...,..;'...i....:;|J;....'.-;'
  Ethyl acefylene [1-Butyn'eT'ZZ"	—-•----"-"---........	.,::...,.:.|j™.;;
  2-Butene	..	..::..„....      	---'•-----—--.:....-,.......,....	......£...„
  Vinyl methyl ether [EtneiieT meSoxHT""""	"---•"-•••"-—-—•—--.....-U---
  Methyl formate Formic acid, methyl ester]""""-""'''"""""'"	"'""'------p-
  Pentane	.............;..	              """;	'	•••••—"———••————V—-..-iS"/.i:.

 Vinyl ethyl ether {Ethene,' ethoxy-iZ '''"''"""""""'"''"'"""•••"•••••••••••••:•••••• '•••••••^>•••
 Ethyl nitrite [Nitrous acid, ethyl esteri     """"•""•"••••"-••-•-"-—-----.;....4---
 Propylene [1-Propene]  ..          '	"r™"	•-—•:•—••••:•.	.--':.	&...;,
 Methyl ether [Methane, oxybis-J """""	"	""""v	-••—--;•-—	v....,.p;:^
 2^lethy!propene[1-Propene,2-meth'yH"""r"""""""'"^"'	:-«•••»;•••••-»—£
 Tetrafluoroethylene [Ethene, tetrafluorcA '""•""•""-•-"••"••—•-••••'—.............^
 Dimethylamine [Methanamine, N-methvl-T"""""""""""""""	"""	'	"-F
'Cyanogen [Ethanedinitrile]  .                """	'	••--•—••	......-.......„!
 Propadiene^[1,2-Propadienel -.."!""""""	-.-.....	;.^...._
 Caibon oxysuifide-[Carbon oxide sulfide"(c"6sTr""""""""""""""":	'"	--"X"-
^Dimethylpropane [Propane, 2,2^ime%l-] "•	""	-•"—••-••-	-^
 1,3-Pentadiene ........             ;          •—•—	—	....„,.;....
   Mote: Basis for Listing:,:  a ;Mandated for listing by Congress./
                                                                                    GAS No.
    74-84^-d
    74-85-1
:v.  74-86-2
 "  74-89^5
 .,74-98-6
.  74-99-7:
   75-00-3
   75-O1-4
   75-02-5
   75-04-7
   75-07-0
   75-08-1
   75-19-4
   75-28-5
  .7,5-29-^
  -75-31-Q
.. 75-35-4
 '75-<37-6
  75-38-7
  7&-50-3
  75-76^-3
 .78-78-4
  78-79-5
  79-^38^9
 106-97-8
                                                                                    106-99-0
                                                                                    107-00-6
                                                                                ..... .107,7-01-7
                                                                                  •107-25-5'
                                                                                ."107-31-3
                                                                              -..    10'9-66-0
                                                                                    109-67-1
                                                                                    109-92-2
                                                                                   109-95-5
                                                                               .   115-07-1
                                                                                   115-10HB
                                                                                  ;i 15-11-7
                                                                               •-••  ^16-14-3
                                                                                   124-40-3
                                                                                  460-19-5
                                                                                  463-49-0
                                                                                ' 463-68-t
                                                                              Y  463-82-1
                                                                                  504-60-9
                                                                                  557-98^2
                                                                                  563-45-1
                                                                                 .563-46-2
                                                                                  590-18-1
                                                                                •  590-21-6
                                                                                  598-73-2
                                                                                  624-64-6
                                                                                  627-20-3
                                                                                  646-04-8
                                                                                  689-97-4
                                                                                1333-74-0
                                                                                4109-96-^0
                                                                                '7791-21-1
                                                                                7803-62-5
                                                                               10025-78-2
                                                                              25167-67-3
                                                                                                 'quantity
                                                                                                    (Ibs)
    10,000
    10,000
    10,000
    10,000
    10,000
    10,000
 x  10,000
:'"   10,000
   10,000
   10,000
   10,000
 .  10,000
   10,000
   10,000
   10,000
  .10,000
   10,000
   10,000
   10,000
   10,000
  10,000
  10,000
  10,000
  10,000
  10,000
  i 0,000
 -10,000
  10,000
 10,000
 10,000
                          Basis for
                           listing
                                                                                                             g
                                                                                                                                g,
               10,000
               10,000
          g
          g
              10,000
              •10,000
             "-10,000
              io.ooo
              10,000
              10,000
              10,000
              10,000'
              10,000
              10,000
              10,000  f
              10,000  f
              10,000  g
             10,000  f
                                               Flammable gas.    g   VolatileJIammable liquid
             :10,000
             :i 0,000
             10,000
             10,000
             10,000
             10,000
             10,000
             10,000
           .  10,000
             10,000
             10,000
             10,000
             10,000
             io.ooo
 IFRDqc. 94-1556 Filed 1-28-94; 8:45 am]
 BIUJNQ CODE i656(«(M>  ''•"'•

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                                              No. 20 /Monday, January 31, 1994  / Notices^
ENVIRONMENTAL PROTECTION
AGENCY
lFRt-4828-7]

List of Regulated Substances for
Accidental Release Prevention Under
Section 112{r) of the Clean Air Act as
Amended; Risk Management Programs
for Chemical Accident Release
Prevention Under Section 112(r)(7) of
the Clean Air Act as Amended
AGENCY: Environmental Protection
Agency (EPA).
ACTION: Supplemental notice.	
 SUMMARY: The Clean Air Act
 Amendments of 1990, signed into law
 on November 15,1990, include
 provisions for chemical accident
 prevention. Elsewhere in this issue of
 the Federal Register, the Environmental
 Protection Agency is promulgating the
 list of regulated substances and
 thresholds required under section 112
 (r) of the Clean Air Act as amended. The
 list and threshold quantities will
 identify facilities subject to chemical
 accident prevention regulations to be
 promulgated under section 112(r) of the
 Clean Air Act as amended; a proposed
 regulation for such requirements was
 published in the Federal Register on
 October 20,1993 (58 FR 54190). In
 promulgating the list, EPA i.s deferring
 action on threshold quantities for listed
 flammable substances when used solely
 for facility consumption as fuel (see 58
 FR 5102,5120, (January 19,1993)). EPA
 , requests additional public comment on
  the hazards associated with flammables
  used as fuel and the appropriateness of
  the proposed exemption. In addition,
  EPA requests comments on the impacts
  of proposed accident prevention
  requirements under section 112(r)(7), on
  sources that would be covered by the
  requirements in the absence of an
  exemption, and on ways of reducing the
  impacts of these requirements.
  Comments  will be placed in the dockets
  for both the list of regulated substances
  and the chemical accident prevention
  regulations.
  DATES: Comments must be submitted on
  or before March 2,1994.
  ADDRESSES: Comments may be mailed
  or submitted to: Environmental
  Protection  Agency, Attn: Docket No. (A-
   91-74), room 1500, Waterside Mall, 401
  M Street SW., Washington, DC 20460.
   Comments must be submitted in
   triplicate.                        '  .
   DOCKET: Supporting information used ui
   developing both the proposed and final
   list rules is contained in Docket No. A-
   91-74. Supporting information used in
   developing the chemical accident
prevention regulations proposed rule is
contained in Docket No. A-91-73.
These dockets are available for public
inspection and copying between 8 a.m.
and 4p.m., Monday through Friday at
the address listed above. A reasonable
fee may be charged for copying.
FOR FURTHER INFORMATION CONTACT:
Vanessa Rodriguez (202) 260-7913, _
Chemical Emergency Preparedness and
'Prevention Office (5101), US
Environmental Protection Agency, 401
M Street SW., Washington, DC 20460, or
the Emergency Planning and
Community-Right-to-Know Hot Line at
1-800-535-0202,
SUPPLEMENTARY INFORMATION:
 I. Introduction
  A. Statutory.Authority           -
  B. Background
 II. Use of Flammable Substances as Fuel
  A. Regulatory History
  B. Hazards Information
  C. Regulatory Impact

 I. Introduction

 A. Statutory Authority
   This notice is being issued under
 sections 112(r) and 301 of the Clean Air.
 Act (CAA or Act) as amended (42 U.S.C.
 7412(r), 7601).
  B. Background
    Section 112(r) of the Clean Air Act of
  1990 establishes chemical accident
  prevention provisions that-focus on
  chemicals posing a significant hazard to
  the community. The intent of these
  provisions is to require facility risk
  management practices that will prevent
  chemical accidents from occurring and
  will minimize the impacts of accidents
  that do occur. Section 112(r)(3) of the
  CAA requires EPA to promulgate an
  initial list of at least 100 substances
  ("regulated substances") that are known
  to cause, or may be reasonably
  anticipated to causa, death, injury, or
  adverse effects to human health and the
  environment. Section 112(r)(5) requires
  EPA to set threshold quantities for each
  listed substance. EPA is promulgating
  the list of regulated substances and
  threshold quantities elsewhere in this
  issue of the Federal Register. The list is
  composed of three categories: toxic
  substances, flammable substances, and
  explosive substances. Threshold
  quantities for toxic substances range   ,
  from 500 to 20,000 pounds. For all
  listed flammable substances, the
  threshold quantity is 10,000 pounds,
   and for all explosive substances, the
   threshold quantity is 5,000 pounds.
     Under CAA section 112(r)(7), the Act
   requires EPA to promulgate reasonable
   regulations and appropriate guidance to
   provide for the prevention and detection
of accidental releases and for response
to such releases. The accident
prevention regulations will apply to
stationary sources that have present
more than a threshold quantity of a
regulated substance. These regulations
shall address, as appropriate, the use,
operation, repair, and maintenance of .
equipment to monitor, detect, inspect,
and control releases, including training
of personnel in the use and maintenance
of equipment or in the conduct of
periodic inspections. The regulations
shall include requirements for the
development and submission of Risk
Management Plans (RMPs) by regulated
facilities. The RMP shall include a
hazard assessment, a prevention
program, and an emergency response
program^ The proposed rule for accident
 prevention, Risk Management Programs
 for Chemical Accidental Release
 Prevention, was published on October
 20,1993 (58 FR 54190).
 II. Use of Flammable Substances as
 Fuel
 A. Regulatory History
   In the proposed rule to establish a list
 of regulated substances (58 FR 5102,
 5120 (January 19,1993)), EPA proposed
 to exempt from the 10,000-pound
 threshold determination flammable
 substances!used solely for facility -
 'consumption as fuel. The final rule
  establishing a list of regulated
  substances (see the final rule published
  elsewhere in this issue) defers action on
  this exemption. EPA plans to make a
  determination on the exemption before
  or at the time:it publishes a final rule
 •for risk management planning.       "• -
    A number of commenters. supported
  the exemption, arguing that it is
  appropriate to exclude on-site storage
  and use of hydrocarbon fuels for what
  were referred to as "low risk
  applications" (e.g., heating and drying).
  Some-commenters appeared to interpret
  the exemption to apply to process-
  related operations, such as process
  heaters; this exclusion was not intended
  by the Agency. It also was argued by
   commenters that current fire protection
   standards and emergency procedures
   provide acceptable means to prevent
   accidental releases and minimise the
   impacts in the event of a release.
     Other commenters opposed an
   exemption for facility'consumption as
   fuel. These commenters. argued that use
   of flammable substances for fuel is _
   probably responsible for more public
   risk than all other uses of flammables
   combined, and that the Agency had not
   made hazard- or risk-based arguments in
   support of the exemption. These
   commenters noted that the proposed

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               ^.  Federal  Register / Veil: 59, No. 20 -../. Monday; January 3lfl994 I Notices
                                                                      4561
 exemption- would allow the handling of
 large quantities of listed flammable  -
 ?ubstances without the development of
 risk management.plan's, -  . ;   :   .-•'• •.'  .•
  The Agency'currently lacks      '•
 information or evidence to demonstrate'
 that the hazard and potential for an -
.accidental release is different for the
 storage, trafisfer, or use of a flammable •-'
 substance'used solely as fuel from the ' ;
•storage, transfer,,or use of the.same.,   '
 substance in a chemical process. The
 Agency also has data available in the .   :
 docket indicating that flammable
"substances used solely as fuel have been
 involved in accidental releases,"    ;
 Therefore, the Agency seeks comment '•;...
 on the appropriateness of this       '  .-•••
 exemption.  ..,..;   ;   ,:.".    '  ';. ',,/•" ••-

 B. Hazards Information       •      •  '
  EPA requests' comments supported by .-
 data on the hazards associated with the.
 use of EPA-listed fiamhiable substances
 as fuel. In particular, the Agency seeks',
 data on actual and potential off-site
 impacts. For example, EPA recognizes -
 that serious hazaidVare associated with
.propane,'but would like additional  •
 information concerning the impacts of
 propane accidents, as related to propane
 use as fuel, on the public. EPA also   :'
 requests comment on whether a hazard-
 based distinction'can be made between
 flammable substances used as fuel and '
 flammable substances otherwise^: •    :
 regulated under the accident prevention
 program. In particular, are the hazards
 associated with handling flammables for
 fuel uses greater or lower than the   ' '
 hazards associated with using the same
 substances in industrial processes •
 otherwise regulated under the accident
 prevention program?         -
   The Occupational Safety and Health""
 Administration (OSHA) exempted
 under its process safety management
 standards "Hydrocarbon fuels used
 solely for workplace consumption as a
 fuel * * .,* • if such fuels are not part of
 a process containing another highly
 hazardous chemical covered by the -    <
 [process safety management] standard"
 (see 57 FR 6356, 6367 (February 24,    : .
 1992)). In part, OSHA's expressed   '  .
 rationale was that this type of use did  ^
 not have the same catastrophic potential
 to workers.as other uses. Fuel storage
 and handling may be systematically
 different (due to industrial standards,
 technology, and regulation) than storage
 and handling of a substance for other
 uses. EPA requests comments supported
 by available data regarding whether the;
 use of a flammable substance as .a fuel
 affects the amount of the substance that
. may reasonably be anticipated to cause
 off-site impacts of concern as a result of
 an accidental release. Another question
 concerns the extent to which a hazard-
 based distinction can be made between
 the EPA-regulated flammables and the
 larger OSHA universe of flammable
 substances when they are used as fuel.
 C. Regulatory Impact.

  EPA requests additional information
 on: (1) the kinds of substances, (2) the
 types and number of facilities,
 especially small businesses, and (3) the
 uses of flammables that would be
 affected by an exemption for the use of
 flammable substances as fuels. EPA also
 requests comment on the
 appropriateness of the risk management.
 program as described in the proposed
 rule of October 20,1993 (see 58 FR
 54190) for this regulated universe.
  Comments are sought on the extent
 and effectiveness of existing'voluntary
, and regulatory programs that inay
 redu.ce hazards associated with the use :
 oli,flanimables as fuel, as well as the,   -
 d€|gree to which such requirements'
 accomplish the same goals (e.g.,   ,  .
 availability pf information to the puMiej
 as|th'e proposed chemical accident   :
 pffeveiilipn prograni and plans.^For  :"
 iiiStance, information on die OSHA
 pife'cess safety management standard
 ajtd on fire protection measures and
 emergency procedures at the state and
 local levelis requested. As OSHA noted,.
 the OSHA standards for flammable arid -
 combustible liquids and, liquified  '
- petooloum gases address flammables
 ufjfed as fuel (see 57 FR 6367); Do these
 standards fuifiirparticular aspects of
 EISA's proposed program, such as the
 pijeyeiition program element?      •    •
   EPA alsp seeks comment  on ways to   ,
 reduce the impact of the risk   .    -
 management planning regulations on.   •_
 usiers of flamrnables as fuel if the
 Agency determines that an exemption is
 n
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|7  ?
                                                        j.  -,,  (jr  —r 5—TT  f^  -1  j— ip -5   -^^3^1

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Ite

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           Federal Register'/  VoL 59, No. 20 /Monday,  January 31,
                                                     Regulations     4479
program, EPA headquarter? and regional
staff, as well as state and local officials,
learned about integrated approaches to
process safety from facilities. EPA has
also worked with trade associations,
professional'organizations, labor,   ;
environmental groups, and other ,
Federal agencies to determine how best
to reach smaller operations, which .the
section 305(bj study indicated are less
aware of risks than larger facilities. EPA -
has also been an active participant in  *
international efforts related jto chemical
accident prevention, particularly
through the Organization for Economic
Cooperation and Development (OEGD),
which has held-five international
workshops from 1989 through 1991 to
discuss issues related to accident ,     :
prevention, preparedness-,_arid response, "
and has developed guidelines for   -
member countries.               -.
   In addition to EPA's work in this area,
other agencies and states have
developed programs related to chemical
accident prevention. The Occupational'
Safety and.Health Administration
(OSHA) promulgated a final rule on "_•'.
"chemical.process safety management
amending 29 CFR 1910.109 and adding
29 CFR 1910.119 (57 FR 6356, February
24,1992) as required under section 304
of the Clean Air Act Amendments of   ,
 1990 (CAA Amendments). Four states-
New Jersey, California, Delaware, and
Nevada—have .operational risk
management programs. Additional.,
 states have begun to  address accidental •
release prevention as part of their air
"toxics program development.
   Professional and trade organizations
have also developed programs in this  .
 area. For example, the Center for
 Chemical Process Safety of the
 American Institute of Chemical
 Engineers has published guidance on
 the management of chemical process
 safety. The Chemical Manufacturers'   ..
 Association has adopted a Responsible
 Care™ program, which all members
 must comply with to maintain .    "
 membership. The American. Petroleum
 Institute has developed a similar
 program, Management of Process-
: Hazards; Recommended Practice 750
 (RP 750), for its members. In 1982, the
 European Community adopted the   .,
 Seveso Directive (82/501/EEC, as
 amended), which requires facilities ,
 handling certain'chemicals to develop a
 safety report that is similar to a risk
 management plan. "

 •II. Clean Air Act Amendments of 1990
'•A. Preventionof AccidentalReleases
   In the CAA Amendments, signed into
 law on November 15,,1990, Congress
       subsection  (r) to CAA'section 112
for the prevention of chemical
accidents. The goals of the chemical
accident prevention provisions are to
•focus on chemicals that pose a
significant hazard to the community
•should an accident pccur, to prevent  :
their accidental release and to minimize
the consequences of such releases.
   Section 112(r) of the CAA has a
number of provisions. Under section
112(r) owners and operators of       ...
stationary sources who produce,   ;   ;-
process, handle, or store substances
listed under section 112(r)(3) or any   -
other extremely hazardous substances
have a general duty to initiate specific
activities to prevent and mitigate
accidental releases. The general duty  ;_.--.-
requirements apply to stationary sources
regardless of the quantity 'of substances
managed at the facility. Activities such
as identifying hazards which may result
from accidental releases jising-,     -•'•.„
appropriate hazard assessment        \,
techniques; designing, maintaining and
operating a safe facility; and minimizing
. the consequences .of accidental releases
if they occur would be essential     - V:
activities to be taken as necessary to
satisfy the general duty requirements.
As a matter of business practice, owners
 and operators of these stationary,sources
have a. duty to conduct these activities
under section 112(r) in the same manner
 and to the same extent as an employer's
 duties under OSHA's general duty    ';;
 clause in section 654 of title 29 of the
 United States Code.            .
   Section 112(r)(3) of the CAA requires
 EPA to promulgate an initial list of at
 least 100 substances ("regulated
 substances") that are known to cause, or
 may be reasonably anticipated to cause, .
 death, injury; or serious adverse effects.
 to human health, or the environment if
 accidentally released. EPA is required to
 se,t threshold quantities for each listed
 substance. Under CAA section 112(rJ{7),
 the Act requires EPA to promulgate :
 reasonable regulations and appropriate
 guidance to provide for the'prevention -
,- and detection of accidental releases and .
 for responses to such releases. The
 accident prevention regulations will
 apply to stationary sources that have
 present more than a .threshold quantity
 of a regulated substance..These
 regulations shall address, as      v ; -
 appropriate, the use, operation, repair,
 and maintenance of equipment to .
 monitor, detect, inspect, and control
 .releases, including; training of personnel
 in the use and maintenance of
. equipment or in the conduct of periodic
 inspections. The regulations shall
 include requirements for the       •
 development and submission of Risk
 Management Plans {RKlPs) by regulated
 sources. The RMP shall include a
 hazard assessment, a prevention   ,-
 program, and an emergency response
 jprogram-.The proposed rule for accident
 jbfevention, Risk Management Programs
 •jbr Chemical Accidental Release
 Prevention, was published on October
 j|0, 1993 (58 FR 54190).
 f: The Act establishes a Chemical Safety '..
 lind Hazard Investigation Board to
 investigate (or cause to be investigated):
 ibhemical accidents at facilities and  ' ;  ;
 irecbitamend to Congress, Federal, state,
 local authorities, and the public actions ,
 feat can be taken to improve chemical
 isafet'y.-Under the Act; EPA is authorized
 •to conduct studies related to accidental
 releases, including research on hazard
 assessments, hydrogen fluoride, and air
 Dispersion modeling. A report to
 Opn|?ress 6ii hydrogen fluoride was
 completed and published by the Agency
 in September 1993, entitled Hydrogen
 fluoride Study, Report to Congress,
 'section  112(n)(6) of the Clean Air Act as
 Amended.         ,        "  •"?•-.-
 I;  Tlie;Clean Air Act also addressed the -
 ilapproyal of state programs and.    ;
 jdelegation of Federal authorities for all   '
 jsecttpn 112 requirements in* section
 .|112(1). Thus, state Accidental Release
 Prevention programs are approved ,  *
. Ihrougli,the authorities in section '112(1).
• pThe approval provisions of section
 1112(1)(5) include a determination that: A
 iftate program contains the authorities to
 ' issujre; compliance by  all sources within
 the istate with each applicable standard,
 "Sregulation, or requirement; adequate.;
 ijpesources are available to implement the ;
 ;jprojprain; an expeditious     ".,-.-•-""
 ^implementation schedule is in place to   •
 |ensiu-e  that affected sources achieve     '
 Icompliance; and the. state :program is  :   ;
:;, ptherwise in cornpliarice with the   :
 Idbjectives of the Act and guidance .   ;
 ipublished under section 112(1)(2).
 ji THe Agency promulgated a final rule
 '|in November 1993 which addresses the
 [approval requirements of section 112(1) •
"'lerititled Approval of State Programs and
 jDelegation of Federal  Authorities.These
 ! requirements can be -found hi 40 CFR  .
 jp'art 63—SubpartE. Section 63.95 .:.
 jspe<:ifically address the'required      -..
 ;pqomponents of an accidental release   '
 ."[prevention program. The Agency is
 !cun-ently wprking on  developing further
 jguidarice to states in regard to the  ''_
 [Development of an accidental release   •
 [prevention program.   ;      -        '
 [Under section 304 of the CAA   '   :
 ;[A^nendments, OSHA was required to •
 ipramijlgate a chemical process safety
 ,;[rnaiiagbment standard to protect.  .'-'.'
 /[•employees from hazards associated with.
 ! accidental releases of highly hazardous
 Ichemicals in the workplace.. OSHA _.'..'.
 | promulgated a  final rule amending 29 "
 JCFR 1916.1O9 and adding 29 CFR ;/•'"

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4480
Federal  Register / Vol. 59, No. 20 / Monday. January 31, 1994 / Rules, and
   1910.110 (57 FR 6356, February 24,
   19132) that requires a chemical process
   safety management (PSM) program for
   tiny process involving a highly
   hazardous chemical at or above a
   specified threshold quantity. The rule
   applies to a list of highly hazardous
   toxic and reactive substances at
   particular threshold quantities,
   flammable liquids or flammable gases in
  quantities of 10,000 pounds or more and
  to the manufacture of explosives and
  pyrotechnics.

  B.Ust of Substances and Thresholds;  •
  Petitions for Additions and Deletions
  1. Legislative Requirements
    The Act requires EPA to promulgate
  an initial list of at least 100 substances
  that, in the event of an accidental
  release, are known to cause or may
  reasonably bo anticipated to cause
  death, injury, or serious adverse effects
  to human health or the environment. An
  accidental release is defined under CAA
  section 112(r)(2)(A) as "an
  unanticipated emission * *  * into the
  ambient air from a stationary source." In
  developing this list, EPA was required
  to consider, but was not limited to, the
  Hst.of extremely hazardous substances
  (EHSs) promulgated under EPCRA
  (SARA Title 111) section 302.
    Congress listed the follo%ving 16
  substances to be included in the initial
  list (the Chemical Abstracts Service,
  (CAS) Registry number is provided in
  parentheses):
 Chlorine (7782-50-5)
 Ammonia and anhydrous ammonia
   (7664-41-7)
 Methyl chloride (74-87-3)
 Ethyleno oxide (75-21-8)
 Vinyl chloride (75-01-4)
 Methyl isocyanate (624-83-9)
 Hydrogen cyanide (74-90-8)
 Hydrogen sulfide (7783-06-4)
 Toluene diisocyanate, represented by:
 —Toluene 2,4-diisocyanate (584-84-9)
 —Toluene 2,6-diisocyanate (91-08-7)
 —Toluene diisocyanate, unspecified
   Isomer (26471-62-5)
 Phosgene (75-44-5)
 Bromine (7726-95-6)
 Anhydrous hydrogen chloride (7647-
   01-0)
 Hydrogen fluoride (76.64-39-3)
 Anhydrous sulfur dioxide (7446-09-5),
   and
 Sulfur trioxido (7446-11-9)
   No air pollutant for which a national
 primary ambient ah- quality standard
 lias boon established maybe included
 on the list, with the exception of
 anhydrous sulfur dioxide and sulfur
 trioxlde, which must be included. No
substances regulated under Title VI of
the Act as amended may be included on
                                      the list. Title VI covers ozone depleters,
                                      primarily chlorofluorocarbons (CFCs)
                                      and halons. The Act requires EPA to
                                      review, and if necessary revise, the list
                                     . of regulated substances under section
                                      112(r) at least every five years. EPA may
                                      also review and if necessary revise the
                                      list as a result of petitions. EPA is
                                      required to develop procedures for
                                      petitions to the Agency for the addition
                                      of substances to, and deletion of
                                      substances  from, the list; these petition
                                      procedures are to be consistent with
                                      those applicable to  the list of hazardous
                                      air pollutants found in CAA
                                      Amendments section 112(b).
                                      2. Summary of Proposed Rule
                                        On January 19,1993  (58~FR 5102),
                                     EPA proposed a list of 100 toxic
                                     substances and threshold quantities, a
                                     list of 62 flammable substances (gases
                                     and volatile liquids) with threshold
                                     quantities of 10,000 pounds, and
                                     commercial explosives defined by the
                                     Department of Transportation (DOT) as
                                     Division 1.1 (explosives with'mass
                                     explosion hazard) with a threshold
                                     quantity of 5,000 pounds. EPA also
                                     proposed requirements for a petition
                                     process to add or delete chemicals from
                                     the list.  x
                                       Toxic substances were included on
                                     the list based on their toxicity, physical
                                     state, vapor  pressure, production
                                     volume, and accident history. Toxicity
                                     criteria used to identify chemicals as
                                     extremely hazardous.substances (EHSs)
                                    • under EPCRA were used as criteria for
                                     the proposed list. The acute toxicity
                                     criteria are:
                                       (a) Inhalation LC50 S 0.5 milligrams
                                     per liter of air (for,exposure time < 8
                                     hours), or                '
                                       (b) Dermal LDso S 50 milligrams per.
                                     kilogram of body weight, or          T.
                                       (c) Oral LD5o 5 25 milligrams per
                                     kilogram of body weight where LC50 is
                                     the median concentration in air at   . .   •
                                     which 50 percent of the test animals
                                     died, and LDso is the median lethal dose
                                     that killed 50 percent of the test
                                     animals. In the absence of LC50 or LDso
                                     data, LCu, or LEto data were used for
                                     listing, where LCu, is the lethal
                                     concentration low, or lowest
                                     concentration in air at which any of the
                                     test animals died, and LD^ is the lethal-
                                     dose low, or the lowest concentration at
                                    , which any of the test animals died.
                                     Additional substances on the EHS list
                                     meet the secondary EHS toxicity criteria
                                     in light of production volume  (see
                                     appendix B of EPA's Technical
                                     Guidance for Hazards Analysis,
                                     December 1987, which is in the docket
                                     for this rulemaking). A vapor pressure
                                     criterion of 0.5 millimeters of mercury
                                     (mm Hg) was used as  a baseline,  based
                                                                  on the vapor pressure of.toluene
                                                                  diisocyanate,. a substance mandated for •
                                                                  the initial list by Congress; toxic gases
                                                                  and liquids with a vapor pressure of 0.5
                                                                  mm Hg or higher under ambient
                                                                  conditions were considered for listing.
                                                                .  Only toxic chemicals in commercial
                                                                  production, verified through EPA's
                                                                  Toxic Substances Control Act (TSCA)
                                                                  Chemical Inventory, were included on
                                                                  the list. By applying these criteria to the
                                                                  360 chemicals on the EPCRA EHS list,
                                                                ' the Agency identified 87 potential
                                                                  regulated substances for the CAA
                                                                  Amendments section 112(r) list. The
                                                                •  Agency also looked at other data sources
                                                                  (including the OSHA highly hazardous
                                                                  chemical list) to identify 9 more  .
                                                                  substances for the section 112(r) list.   '
                                                                  Four additional substances were
                                                                  identified for listing based on a
                                                                  combination of toxicity, high
                                                                  production volume, and history of
                                                                  accidents involving death or injury.
                                                                 Threshold quantities were set for toxic
                                                                 substances based on a ranking method
                                                                 that considers toxicity and volatility of
                                                                 the chemicals. EPA assigned identical
                                                                 thresholds to chemicals with similar
                                                                 ranking scores, ranging from 500
                                                                . pounds to 10,000 pounds.
                                                                   Flammable gases, and volatile
                                                                 flammable liquids were included on the
                                                                 list based.on the flash point and boiling
                                                                 point criteria used by,the National Fire ,
                                                                 Protection Association (NFPA) for its    '
                                                                 highest flammability hazard ranking
                                                                 (flash point below 73°F(22.8°C) and
                                                                boiling point below 100°F (37.8°C)) (Fire
                                                                Protection Guide on Hazardous
                                                                Materials, 1984, 8th edition). Only
                                                                flammable substances in commercial
                                                                production were listed. The threshold
                                                                quantity for flammable substances was
                                                                set at 10,000 pounds, based on the
                                                                potential for a vapor cloud explosion.
                                                                  Explosives in Division 1.1 were
                                                                proposed for listing based on their -
                                                                potential to detonate. The threshold
                                                                quantity for .explosives was set at 5,000
                                                                pounds because a detonation of this
                                                                quantity'could yield blast wave
                                                                overpressures of 3.0 pounds per square
                                                                inch (psi) at a distance of 100 meters
                                                                from the blast-site and could have  "
                                                                potentially lethal effects in the
                                                                community beyond the fenceline.
                                                                  EPA proposed to apply the threshold
                                                                quantity to the maximum total quantity
                                                                of a substance in a process. This
                                                                definition would apply to the maximum
                                                                total quantity, at any one time, in a
                                                                single vessel, in a group'of
                                                                interconnected vessels or in several
                                                                vessels that could potentially be
                                                                involved at one time in an accidental
                                                                release. Substances in mixtures would
                                                                be exempted from the threshold        '
                                                               "determination if they represent less than

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