[Federal Register Volume 64, Number 101 (Wednesday, May 26, 1999)]
[Rules and Regulations]
[Pages 28696-28701]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-12936]



[[Page 28695]]

_______________________________________________________________________

Part V





Environmental Protection Agency





_______________________________________________________________________



40 CFR Part 68



Accidental Release Prevention Requirements: Risk Management Programs 
Under Clean Air Act Section 112(r)(7); Amendments to the Worst-Case 
Release Scenario Analysis for Flammable Substances; Final and Proposed 
Rules

Proposed Settlement; Clean Air Act 112(r) Accidental Release Prevention 
Requirements: Risk Management Programs Litigation; Notice

  Federal Register / Vol. 64, No. 101 / Wednesday, May 26, 1999 / Rules 
and Regulations  

[[Page 28696]]



ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 68

[FRL-6348-2]


Accidental Release Prevention Requirements: Risk Management 
Programs Under Clean Air Act Section 112(r)(7); Amendments to the 
Worst-Case Release Scenario Analysis for Flammable Substances

AGENCY: Environmental Protection Agency (EPA).

ACTION: Direct final rule.

-----------------------------------------------------------------------

SUMMARY: This direct final action amends the Chemical Accident 
Prevention Provisions, also known as the Risk Management Program (RMP) 
regulations, codified in 40 CFR part 68. The revisions concern the 
worst-case release scenario analysis for regulated flammable substances 
in 40 CFR 68.25. EPA is issuing these revisions so that the regulated 
community can treat regulated flammable substances in the same manner 
as regulated toxic substances for determining the quantity released 
when conducting a worst-case release scenario analysis. EPA is taking 
this direct final action pursuant to a settlement agreement with the 
American Petroleum Institute (API).
    EPA is also clarifying its interpretation of Clean Air Act sections 
112(l) and 112(r)(11), as they relate to Department of Transportation 
(DOT) requirements under the Federal Hazardous Materials Transportation 
Law under a settlement agreement with the Chlorine Institute (CI).

DATES: This rule is effective on June 21, 1999 without further notice, 
unless EPA receives adverse comment by June 16, 1999 or, pursuant to 
CAA section 113(g), declines to finalize the settlement agreement. If 
we receive such comment, or decide to withdraw from the settlement 
agreement, we will publish a timely withdrawal in the Federal Register 
informing the public that this rule will not take effect.

ADDRESSES: Docket and Comments. Docket No. A-99-15, containing 
supporting information used to develop these amendments, is available 
for public inspection and copying from 8:00 a.m. to 5:30 p.m., Monday 
through Friday (except government holidays) from EPA's Air Docket, at 
Waterside Mall, Room M1500, 401 M Street, SW, Washington, D.C., 20460, 
telephone 202-260-7548. Written comments should be submitted to the 
same address. A reasonable fee may be charged for copying.

FOR FURTHER INFORMATION CONTACT: Sicy Jacob or John Ferris, Chemical 
Emergency Preparedness and Prevention Office, Environmental Protection 
Agency (5104), 401 M Street SW, Washington, D.C., 20460, (202) 260-7249 
or (202) 260-4043, respectively; or the Emergency Planning and 
Community Right-to-Know Hotline at 800-424-9346 (in the Washington, DC 
metropolitan area, (703) 412-9810). You may wish to visit the Chemical 
Emergency Preparedness and Prevention Office (CEPPO) Internet site, at 
www.epa.gov/ceppo.

SUPPLEMENTARY INFORMATION:

Regulated Entities

    Entities potentially regulated by this action are those stationary 
sources that have more than a threshold quantity of a regulated 
substance in a process. Regulated categories and entities include:

------------------------------------------------------------------------
                                                Example of regulated
                 Category                             entities
------------------------------------------------------------------------
Petrochemical.............................  Refineries, Plastics,
                                             Resins.
Chemical Manufacturing....................  Organics.
------------------------------------------------------------------------

    This table is not meant to be exhaustive, but rather provides a 
guide for readers to indicate some of those entities likely to be 
regulated by this action. The table lists entities EPA is aware of that 
could potentially be regulated by this action. Other entities not 
listed in the table could also be regulated. To determine whether a 
stationary source is regulated by this action, carefully examine the 
provisions associated with the list of substances and thresholds under 
Sec. 68.130 and the applicability criteria under Sec. 68.10. If you 
have questions regarding applicability of this action to a particular 
entity, consult the hotline or persons listed in the preceding FOR 
FURTHER INFORMATION CONTACT section.

Table of Contents

I. Introduction and Background
    A. Statutory Authority
    B. Background
    C. RMP Rule Litigation
II. Discussion of Revisions to Sec. 68.25
III. Clarification of Section 112(l) and 112(r)(11)
IV. Judicial Review
V. Administrative Requirements
    A. Docket
    B. Executive Order 12866
    C. Executive Order 12875
    D. Executive Order 13045
    E. Executive Order 13084
    F. Regulatory Flexibility
    G. Paperwork Reduction
    H. Unfunded Mandates Reform Act
    I. National Technology Transfer and Advancement Act
    J. Congressional Review Act

I. Introduction and Background

A. Statutory Authority

    These amendments are being promulgated under sections 112(r) and 
301(a)(1) of the Clean Air Act (CAA) as amended (42 U.S.C. 7412(r), 
7601(a)(1)).

B. Background

    The 1990 CAA Amendments added section 112(r) to provide for the 
prevention and mitigation of accidental chemical releases. Section 
112(r) mandates that EPA promulgate a list of ``regulated substances,'' 
with ``threshold quantities''. Processes at stationary sources that 
contain a threshold quantity of a regulated substance are subject to 
accidental release prevention regulations promulgated under CAA section 
112(r)(7). EPA promulgated the list of regulated substances on January 
31, 1994 (59 FR 4478) (the ``List Rule'') and the accidental release 
prevention regulations creating the risk management program 
requirements on June 20, 1996 (61 FR 31668) (the ``RMP Rule''). 
Together, these two rules are codified at 40 CFR part 68. EPA has since 
revised the rules in several respects, and these revisions are 
reflected in the most recent codification of 40 CFR part 68.
    Part 68 requires that any source with more than a threshold 
quantity of a regulated substance in a process develop and implement a 
risk management program that includes a five-year accident history, 
offsite consequence analyses, a prevention program, and an emergency 
response program. In part 68, processes are divided into three 
categories (Programs 1 through 3). Processes that likely have no 
potential impact on the public in the case of accidental releases have 
minimal requirements (Program 1). Processes in Programs 2 and 3 have 
additional requirements based on their potential for offsite 
consequences as indicated by worst-case accidental release analysis and 
their accident history. Program 3 is also triggered if the processes 
are subject to OSHA's Process Safety Management (PSM) Standard. By June 
21, 1999, any source with more than a threshold quantity of a regulated 
substance in a process must submit to EPA a risk management plan (RMP) 
that summarizes their implementation of the risk management program.

C. RMP Rule Litigation

    The American Petroleum Institute (API) and the Chlorine Institute 
(CI) filed petitions for judicial review of the

[[Page 28697]]

RMP Rule (The Chlorine Institute v. EPA, No. 94-1279 (D.C. Cir.) and 
consolidated cases (Nos. 96-1284, 96-1288, 96-1289 & 96-1290)). In 
court filings, API raised issues related to worst-case release scenario 
analysis (Sec. 68.25 of the rule) for flammables.
    In the final RMP rule issued on June 20, 1996, Sec. 68.25(e) states 
that when conducting a worst-case scenario analysis for flammables, the 
owner or operator shall assume that the quantity of the substance, as 
determined under paragraph (b) of Sec. 68.25, vaporizes, resulting in a 
vapor cloud explosion. This approach applies to all listed flammable 
substances regardless of whether the flammable substance is normally a 
liquid or liquefied by refrigeration. API suggested that flammable 
liquids and those liquefied by refrigeration should be treated, for 
modeling purposes, in the same manner as for toxic liquids or those 
liquefied by refrigeration, as stated in Sec. 68.25 (c) and (d). EPA 
agreed that flammable liquids (including those liquified by 
refrigeration) could be appropriately treated in that manner. 
Accordingly, EPA and API signed a proposed settlement agreement in May 
1999. This settlement agreement is awaiting finalization pursuant to 
section 113(g) of the CAA.
    CI's primary litigation concern related to CAA sections 112(l) and 
112(r)(11), as they relate to Department of Transportation (DOT) 
requirements under the Federal Hazardous Materials Transportation Law 
(``Federal Hazmat Law''). EPA and CI reached an agreement on this issue 
and signed a proposed settlement agreement in May 1999. This settlement 
agreement is awaiting finalization pursuant to section 113(g) of the 
CAA.

II. Discussion of Revisions to Sec. 68.25

    40 CFR 68.25 requires each stationary source subject to the RMP 
rule to analyze at least one worst-case release scenario for regulated 
flammables and at least one for regulated toxic substances that are 
present in a process at the stationary source above the threshold 
quantity. A worst-case release means the release of the largest 
quantity of a regulated substance from a vessel or process line failure 
that results in the greatest distance to an endpoint defined in 
Sec. 68.22(a).
    In the final rule promulgated on June 20, 1996, EPA established a 
framework for the worst-case scenario analysis that considers the 
physical state of the substance and the way in which it is stored or 
handled (see 40 CFR 68.25):
    (1) For toxic gases and gases liquefied by pressure, the worst-case 
release scenario assumes that the largest quantity is released in 10 
minutes and the rate of release to the air is the quantity divided by 
10 minutes. Upon loss of containment (e.g. a catastrophic vessel 
failure), a gaseous substance will be completely released to the air 
within 10 minutes. Although gases liquefied by pressure will behave 
initially like a liquid, they will rapidly become gases upon 
catastrophic release because of the sudden release of pressure and 
because the storage temperature of the liquid is often much higher than 
the boiling point of the substance. The rate of flashing and 
volatilization is generally great enough to vaporize the entire 
quantity within 10 minutes.
    (2) For toxic liquids, the worst-case scenario assumes an 
instantaneous spill; the release rate to the air is the volatilization 
rate from a pool that spreads out to a 1 centimeter (cm) depth unless 
passive mitigation (e.g., a diked area) contains the substance in a 
smaller area. The rate of volatilization to the air depends on the 
surface area of the liquid pool and it may be adjusted to account for 
the smaller surface in a contained area.
    (3) For toxic substances liquefied by refrigeration, the scenario 
assumes an instantaneous liquid spill followed by volatilization of the 
pool at the substance's boiling point but only if the spilled liquid is 
contained by passive mitigation at a liquid depth greater than 1 cm. If 
passive mitigation is not present or is of such large capacity that the 
refrigerated liquid spill can spread out to a depth of 1 cm, then the 
quantity of refrigerated liquid is assumed to completely volatilize 
within 10 minutes. Gases liquefied by refrigeration need time to 
vaporize and become a gas because the storage temperature of the liquid 
is less than its boiling point. Therefore, the rate of release to the 
air is less than the total quantity released in 10 minutes. The liquid 
must be contained by passive mitigation at a depth greater than 1 cm; 
otherwise, the rate of warming and volatilization is great enough to 
completely vaporize the spill within 10 minutes.
    For all listed flammables however, the worst case assumes that the 
quantity in the largest vessel or pipeline vaporizes to form a vapor 
cloud, followed by a vapor cloud explosion. No consideration was given 
for liquids or substances liquefied by refrigeration, primarily because 
EPA assumed that passive mitigation or containment was typically not 
used under flammable storage due to fire safety reasons. The American 
Petroleum Institute (API) argued that, in many cases, spilled flammable 
liquids are, in fact contained, but in a way that prevents a liquid 
fire from impacting storage vessels and prevents release to the 
environment. Such containment serves to reduce the quantity available 
for a vapor cloud explosion in the same way that liquid toxics generate 
a smaller toxic vapor cloud than gases. If the flammable worst-case 
scenario were revised to account for liquids in the same way as toxics, 
then the flammable worst-case scenario could distinguish flammable 
gases from liquids to avoid generating a technically incorrect and 
overly conservative result.
    EPA agrees that the worst-case assessment for flammable liquids and 
flammables liquefied by refrigeration is not consistent with the 
approach for toxic liquids or toxics liquefied by refrigeration. EPA is 
thus taking direct final action to revise Sec. 68.25(e) so that 
flammables may be treated in a manner consistent with the treatment of 
toxics.
    Specifically, EPA is making the following changes to Sec. 68.25 for 
flammables: (1) For regulated flammable substances that are normally 
gases at ambient temperature and handled as a gas or as a liquid under 
pressure, the owner or operator shall assume that the quantity in the 
vessel or pipe, as determined under Sec. 68.25(b), is released as a gas 
over 10 minutes. The total quantity shall be assumed to be involved in 
the vapor cloud explosion. (2) For regulated flammable substances that 
are normally liquids at ambient temperature, the owner or operator 
shall assume that the entire quantity in the vessel or pipe, as 
determined under Sec. 68.25(b), is spilled instantaneously to form a 
liquid pool. For liquids at temperatures below their atmospheric 
boiling point, the volatilization rate shall be calculated at the 
conditions specified in Sec. 68.25(d). The owner or operator shall 
assume that the quantity which becomes vapor in the first 10 minutes is 
reported as the quantity released. (3) For flammable gases handled as 
refrigerated liquids at ambient pressure, the owner or operator may 
assume that the total quantity of the substance determined in 
Sec. 68.25(b) instantaneously spills followed by volatilization of the 
liquid pool at the substance's boiling point and under the conditions 
specified in Sec. 68.25(d), provided the spilled liquid would be 
contained by passive mitigation at a liquid depth greater than 1 cm. 
The quantity of substance that becomes vapor in the first 10 minutes is 
involved in the vapor cloud explosion. If passive mitigation is not 
present or is of such large capacity that the refrigerated liquid spill 
can spread out to a depth of 1 cm, then the quantity of refrigerated

[[Page 28698]]

liquid is assumed to completely volatilize within 10 minutes and the 
total quantity is involved in the vapor cloud explosion.
    This modification allows stationary sources to account for 
volatilization of the liquid pool if flammables are liquefied by 
refrigeration; however, sources are not required to use this added 
assumption. Sources can still use the quantity determined under 
Sec. 68.25(b) as the quantity released. Sources that have already 
submitted their RMP may choose to use this revised approach, but are 
not required to do so. Sources that choose to use this revised 
approach, must revise and re-submit their RMP to EPA by June 21, 1999.
    EPA will not be modifying RMP*SubmitTM (the computer 
database used to report the RMPs) as a result of this rule at this 
time. Instead, stationary sources reporting for flammables liquefied by 
refrigeration would need to calculate the total quantity of the gas 
generated (taking the volatilization rate into account) from the pool 
in a 10-minute period. This value would be reported as ``Quantity 
released'' in section 4.4 of RMP*SubmitTM. The passive 
mitigation (dikes, berms, etc.) considered would be specified at 
``Other'' in section 4.10. EPA also suggests that stationary sources 
utilize the Executive Summary section of RMP*SubmitTM to 
explain how they calculated the quantity released for the refrigerated 
flammable substances.
    Section 68.25(e) will be revised by adding (i) and (ii) and adding 
a new (f); existing (f), (g), and (h) will become (g), (h), and (i).
    EPA is publishing this rule without prior proposal because we view 
this as consistent with the original rule as promulgated and as a 
noncontroversial amendment. No adverse comment is anticipated. The sole 
regulatory change contemplated under the settlement agreement 
represents a narrow technical amendment designed to make the treatment 
of flammables consistent with that of toxics. This amendment merely 
adjusts the way in which releases of these substances are modeled and 
does not alter the number of sources subject to RMP or the basic 
obligations under the RMP. In light of the foregoing and the need to 
promulgate the revision prior to the rule's June 21, 1999 compliance 
date, the Agency believes a direct final rule is the most appropriate 
vehicle for implementation of the settlement agreement.
    In the ``Proposed Rules'' section of today's Federal Register 
publication, we are publishing a separate document that will serve as 
the proposal to revise Sec. 68.25 for flammables if adverse comments 
are filed. This rule will be effective on June 21, 1999, without 
further notice unless we receive adverse comment by June 16, 1999. If 
EPA receives adverse comment, we will publish a timely withdrawal in 
the Federal Register informing the public that the rule will not take 
effect. We will address all public comments in a subsequent final rule 
based on the proposed rule. We will not institute a second comment 
period on this action. Any parties interested in commenting must do so 
at this time.

III. Clarification of CAA Sections 112(l) and 112(r)(11)

    Pursuant to the settlement agreement with CI, EPA is clarifying its 
interpretation of CAA sections 112(l) and 112(r)(11), as they relate to 
DOT requirements under the Federal Hazardous Materials Transportation 
Law, 49 U.S.C. 5101-5127.
    In our amendments to 40 CFR part 68 (63 FR 640, January 6, 1998) we 
dealt with the issue of the relationship between part 68 and statutes 
administered by and regulations promulgated by the Department of 
Transportation (DOT), such as the Federal Hazardous Materials 
Transportation Law (``Federal Hazmat Law'') and the Hazardous Materials 
Regulations (``HMR''). We noted therein that: ``EPA's regulations do 
not supersede or limit DOT's authorities and, therefore, are in 
compliance with CAA section 310.''
    The definition of stationary source finalized in that rule 
generally provides that containers that are in transportation or 
storage incident to transportation are not part of a stationary source 
or a process at the stationary source. On the other hand, the 
definition of stationary source does provide that such containers are 
part of a stationary source under certain circumstances, most notably 
when they are being loaded, unloaded or on site for storage not 
incidental to transportation. Because a transportation container may at 
times function as a storage container or a process at a stationary 
source, or may function as part of operations at a stationary source, 
EPA is specifically directed by statute to address these activities 
(CAA section 112(r)(7)(B)(i)) (``The regulations shall cover storage, 
as well as operations''). To the extent that DOT is also authorized 
under the Federal Hazmat Law to regulate activities that are at a 
stationary source, nothing in the CAA prohibits both agencies from 
exercising concurrent jurisdiction over these activities. As EPA has 
said in the context of the RMP Rule, compliance with Federal Hazmat Law 
and HMR requirements may satisfy parallel requirements of part 68. This 
approach to implementation reflects the coordination between the 
agencies that is called for under CAA section 112(r)(7)(D). The 
exercise of concurrent jurisdiction preserves the applicability of the 
Federal Hazmat Law and HMR and does not supersede or limit DOT's 
jurisdiction. CAA section 310 provides that the CAA shall not be 
construed as superseding or limiting the authority or responsibilities 
of any Federal agency. Thus, neither CAA section 112(r)(11) (which 
provides that section 112(r) does not preempt state regulations that 
are more stringent than EPA's) nor section 112(l) (which allows EPA to 
delegate the accident prevention regulations to a state if the state's 
program is no less stringent than EPA's) can be read to authorize a 
state to regulate in a manner that would otherwise be preempted under 
the Federal Hazmat Law. A state that, for purposes of obtaining 
delegation under section 112(l), adopts Part 68 or a program that is 
substantively the same as Part 68 will not be considered by EPA to 
regulate in a manner that would otherwise be preempted under the 
Federal Hazmat Law.

IV. Judicial Review

    Under section 307(b)(1) of the Clean Air Act (CAA), judicial review 
of this rule is available only by filing a petition for review in the 
U.S. Court of Appeals for the District of Columbia Circuit within 60 
days of this notice, unless EPA withdraws this rule as described 
earlier in this notice. Under section 307(b)(2) of CAA, the 
requirements that are the subject of today's document may not be 
challenged later in civil or criminal proceedings brought by EPA to 
enforce these requirements.

V. Administrative Requirements

A. Docket

    The docket is an organized and complete file of all the information 
considered by the EPA in the development of this rulemaking. The docket 
is a dynamic file, because it allows members of the public and 
industries involved to readily identify and locate documents so that 
they can effectively participate in the rulmaking process. Along with 
the proposed and promulgated rules and their preambles, the contents of 
the docket serve as the record in the case of judicial review. (See 
section 307(d)(7)(A) of the CAA.)
    The official record for this rulemaking, as well as the public 
version, has been established for this

[[Page 28699]]

rulemaking under Docket No. A-99-15, and is available for inspection 
from 8:00 a.m. to 5:30 p.m., Monday through Friday, excluding legal 
holidays. The official rulemaking record is located at the address in 
ADDRESSES at the beginning of this document.

B. Executive Order 12866

    Under Executive Order 12866, (58 Federal Register 51,735 (October 
4, 1993)) the Agency must determine whether the regulatory action is 
``significant'' and therefore subject to OMB review and the 
requirements of the Executive Order.
    The Order defines ``significant regulatory action'' as one that is 
likely to result in a rule that may: (1) Have an annual effect on the 
economy of $100 million or more or adversely affect in a material way 
the economy, a sector of the economy, productivity, competition, jobs, 
the environment, public health or safety, or State, local, or tribal 
governments or communities; (2) Create a serious inconsistency or 
otherwise interfere with an action taken or planned by another agency; 
(3) Materially alter the budgetary impact of entitlements, grants, user 
fees, or loan programs or the rights and obligations of recipients 
thereof; or (4) Raise novel legal or policy issues arising out of legal 
mandates, the President's priorities, or the principles set forth in 
the Executive Order.''
    It has been determined that today's action is not a ``significant 
regulatory action'' under the terms of E.O. 12866 and is, therefore, 
not subject to OMB review.

C. Executive Order 12875

    Under Executive Order 12875, EPA may not issue a regulation that is 
not required by statute and that creates a mandate upon a State, local 
or tribal government, unless the Federal government provides the funds 
necessary to pay the direct compliance costs incurred by those 
governments, or EPA consults with those governments.
    If EPA complies by consulting, Executive Order 12875 requires EPA 
to provide to the Office of Management and Budget a description of the 
extent of EPA's prior consultation with representatives of affected 
State, local and tribal governments, the nature of their concerns, any 
written communications from the governments, and a statement supporting 
the need to issue the regulation.
    In addition, Executive Order 12875 requires EPA to develop an 
effective process permitting elected officials and other 
representatives of State, local and tribal governments ``to provide 
meaningful and timely input in the development of regulatory proposals 
containing significant unfunded mandates.''
    Today's rule does not create a mandate on State, local or tribal 
governments. This rule change does not impose any enforceable duties on 
these entities. Instead, it merely provides an alternative approach for 
calculating the quantity released in the worst-case scenario. 
Stationary sources already subject to the rule may use this approach 
for conducting worst-case release scenarios for flammable substances in 
the same manner as toxic substances. Accordingly, the requirements of 
section 1(a) of Executive Order 12875 do not apply to this rule.

D. Executive Order 13045

    Executive Order 13045: ``Protection of Children from Environmental 
Health Risks and Safety Risks'' (62 FR 19885, April 23, 1997) applies 
to any rule that: (1) is determined to be ``economically significant'' 
as defined under E.O. 12866, and (2) concerns an environmental health 
or safety risk that EPA has reason to believe may have a 
disproportionate effect on children. If the regulatory action meets 
both criteria, the Agency must evaluate the environmental health or 
safety effects of the planned rule on children, and explain why the 
planned regulation is preferable to other potentially effective and 
reasonably feasible alternatives considered by the Agency.
    This action is not subject to the E.O. 13045 because it is not 
``economically significant'' as defined in E.O. 12866, and because it 
does not involve decisions based on environmental health or safety 
risks.

E. Executive Order 13084

    Under Executive Order 13084, EPA may not issue a regulation that is 
not required by statute, that significantly or uniquely affects the 
communities of Indian tribal governments, and that imposes substantial 
direct compliance costs on those communities, unless the Federal 
government provides the funds necessary to pay the direct compliance 
costs incurred by the tribal governments, or EPA consults with those 
governments.
    If EPA complies by consulting, Executive Order 13084 requires EPA 
to provide to the Office of Management and Budget, in a separately 
identified section of the preamble to the rule, a description of the 
extent of EPA's prior consultation with representatives of affected 
tribal governments, a summary of the nature of their concerns, and a 
statement supporting the need to issue the regulation. In addition, 
Executive Order 13084 requires EPA to develop an effective process 
permitting elected officials and other representatives of Indian tribal 
governments ``to provide meaningful and timely input in the development 
of regulatory policies on matters that significantly or uniquely affect 
their communities.''
    Today's rule does not significantly or uniquely affect the 
communities of Indian tribal governments. This rule change merely 
provides an alternative approach for calculating the quantity released 
in the worst-case scenario. Stationary sources already subject to the 
rule may use this approach for conducting worst-case release scenarios 
for flammable substances in the same manner as toxic substances. 
Accordingly, the requirements of section 3(b) of Executive Order 13084 
do not apply to this rule.

F. Regulatory Flexibility

    EPA has determined that it is not necessary to prepare a regulatory 
flexibility analysis in connection with this direct final rule and that 
this rule will not have a significant negative economic impact on small 
entities. This rule change does not require any stationary source to 
report additional elements in the risk management plan. It merely 
provides an alternative approach for stationary sources already subject 
to the rule to use for conducting worst-case release scenarios for 
flammable substances.

G. Paperwork Reduction

    The Office of Management and Budget (OMB) has approved the 
information collection requirements contained in this rule under the 
provisions of the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. and 
has assigned OMB control number 2050-0144.
    This rule does not include any new information collection 
requirements for OMB review under the provisions of the Paperwork 
Reduction Act. This revision of the rule does not impose any new 
reporting, recordkeeping, or third party reporting requirements on 
stationary sources, it merely provides an alternative approach for 
sources to calculate the quantity released in the worst-case scenario 
for flammables. The Office of Management and Budget (OMB) has approved 
the information collection requirements contained in this rule under 
the provisions of the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. 
and has assigned OMB control number 2050-0144.
    Burden means the total time, effort, or financial resources 
expended by persons

[[Page 28700]]

to generate, maintain, retain, or disclose or provide information to or 
for a Federal agency. This includes the time needed to review 
instructions; develop, acquire, install, and utilize technology and 
systems for the purposes of collecting, validating, and verifying 
information, processing and maintaining information, and disclosing and 
providing information; adjust the existing ways to comply with any 
previously applicable instructions and requirements; train personnel to 
be able to respond to a collection of information; search data sources; 
complete and review the collection of information; and transmit or 
otherwise disclose the information.
    An Agency may not conduct or sponsor, and a person is not required 
to respond to a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for EPA's 
regulations are listed in 40 CFR part 9 and 48 CFR Chapter 15. EPA is 
amending the table in 40 CFR part 9 of currently approved ICR control 
numbers issued by OMB for various regulations to list the information 
requirements contained in this final rule.

H. Unfunded Mandates Reform Act

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public 
Law 104-4, establishes requirements for Federal agencies to assess the 
effects of their regulatory actions on State, local, and tribal 
governments and the private sector. Under section 202 of the UMRA, EPA 
generally must prepare a written statement, including a cost-benefit 
analysis, for proposed and final rules with ``Federal mandates'' that 
may result in expenditures to State, local, and tribal governments, in 
the aggregate, or to the private sector, of $100 million or more in any 
one year. Before promulgating an EPA rule for which a written statement 
is needed, section 205 of the UMRA generally requires EPA to identify 
and consider a reasonable number of regulatory alternatives and adopt 
the least costly, most cost-effective or least burdensome alternative 
that achieves the objectives of the rule. The provisions of section 205 
do not apply when they are inconsistent with applicable law. Moreover, 
section 205 allows EPA to adopt an alternative other than the least 
costly, most cost-effective or least burdensome alternative if the 
Administrator publishes with the final rule an explanation why that 
alternative was not adopted. Before EPA establishes any regulatory 
requirements that may significantly or uniquely affect small 
governments, including tribal governments, it must have developed under 
section 203 of the UMRA a small government agency plan. The plan must 
provide for notifying potentially affected small governments, enabling 
officials of affected small governments to have meaningful and timely 
input in the development of EPA regulatory proposals with significant 
Federal intergovernmental mandates, and informing, educating, and 
advising small governments on compliance with the regulatory 
requirements.
    EPA has determined that this rule does not contain a Federal 
mandate that may result in expenditures of $100 million or more for 
state, local, and tribal governments, in the aggregate, or the private 
sector in any one year. Today's action is not subject to the 
requirements of sections 202 and 205 of the Unfunded Mandates Act.
    Today's rule contains no Federal mandates (under the regulatory 
provisions of Title II of the UMRA) for state, local, or tribal 
governments or the private sector. This rule change does not require 
any stationary sources to report additional elements in the risk 
management plan. It merely provides an alternative approach for 
stationary sources already subject to the rule to use for conducting 
worst-case release scenarios for flammable substances.
    In addition, for the same reasons, EPA has determined that this 
rule contains no regulatory requirements that might significantly or 
uniquely affect small governments.

I. National Technology Transfer and Advancement Act

    Section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (``NTTAA''), Public Law 104-113, section 12(d) (15 U.S.C. 
272 note), directs EPA to use voluntary consensus standards in its 
regulatory activities unless to do so would be inconsistent with 
applicable law or otherwise impractical. Voluntary consensus standards 
are technical standards (e.g., materials specifications, test methods, 
sampling procedures, business practices) that are developed or adopted 
by voluntary consensus standards bodies. The NTTAA requires EPA to 
provide Congress, through OMB, explanations when the Agency decides not 
to use available and applicable voluntary consensus standards.
    This action does not involve technical standards. Therefore, EPA 
did not consider the use of any voluntary consensus standards.

J. Congressional Review Act

    The Congressional Review Act, 5 U.S.C. 801 et. seq., as added by 
the Small Business Regulatory Enforcement Fairness Act of 1996, 
generally provides that before a rule may take effect, the agency 
promulgating the rule must submit a rule report, which includes a copy 
of the rule, to each House of the Congress and to the Comptroller 
General of the United States. EPA will submit a report containing this 
rule and other required information to the U.S. Senate, the U.S. House 
of Representatives, and the Comptroller General of the United States 
prior to publication of the rule in the Federal Register. This action 
is not a ``major rule'' as defined by 5 U.S.C. 804(2). This rule will 
be effective on June 21, 1999.

List of Subjects in 40 CFR Part 68

    Environmental protection, Chemicals, Chemical accident prevention.

    Dated: May 17, 1999.
Carol M. Browner,
Administrator.

    For the reasons set out in the preamble, title 40, chapter I, 
subchapter C, part 68 of the Code of Federal Regulations is amended to 
read as follows:

PART 68--CHEMICAL ACCIDENT PREVENTION PROVISIONS

    1. The authority citation for Part 68 continues to read as follows:

    Authority: 42 U.S.C. 7412(r), 7601(a)(1), 7661-7661f.

Subpart B--Hazard Assessment

    2. Section 68.25 is amended by redesignating paragraphs (f), (g), 
and (h) as (g), (h), and (i), and by revising paragraph (e) and adding 
a new paragraph (f) to read as follows:


Sec. 68.25  Worst-case release scenario analysis.

* * * * *
    (e) Worst-case release scenario--flammable gases. The owner or 
operator shall assume that the quantity of the substance, as determined 
under paragraph (b) of this section and the provisions below, vaporizes 
resulting in a vapor cloud explosion. A yield factor of 10 percent of 
the available energy released in the explosion shall be used to 
determine the distance to the explosion endpoint if the model used is 
based on TNT equivalent methods.
    (1) For regulated flammable substances that are normally gases at 
ambient temperature and handled as a gas or as a liquid under pressure, 
the owner or operator shall assume that the quantity in the vessel or 
pipe, as determined under paragraph (b) of this section, is released as 
a gas over 10 minutes. The total quantity shall be

[[Page 28701]]

assumed to be involved in the vapor cloud explosion.
    (2) For flammable gases handled as refrigerated liquids at ambient 
pressure:
    (i) If the released substance is not contained by passive 
mitigation systems or if the contained pool would have a depth of one 
centimeter or less, the owner or operator shall assume that the total 
quantity of the substance is released as a gas in 10 minutes, and the 
total quantity will be involved in the vapor cloud explosion.
    (ii) If the released substance is contained by passive mitigation 
systems in a pool with a depth greater than 1 centimeter, the owner or 
operator may assume that the quantity in the vessel or pipe, as 
determined under paragraph (b) of this section, is spilled 
instantaneously to form a liquid pool. The volatilization rate (release 
rate) shall be calculated at the boiling point of the substance and at 
the conditions specified in paragraph (d) of this section. The owner or 
operator shall assume that the quantity which becomes vapor in the 
first 10 minutes is involved in the vapor cloud explosion.
    (f) Worst-case release scenario--flammable liquids. The owner or 
operator shall assume that the quantity of the substance, as determined 
under paragraph (b) of this section and the provisions below, vaporizes 
resulting in a vapor cloud explosion. A yield factor of 10 percent of 
the available energy released in the explosion shall be used to 
determine the distance to the explosion endpoint if the model used is 
based on TNT equivalent methods.
    (1) For regulated flammable substances that are normally liquids at 
ambient temperature, the owner or operator shall assume that the entire 
quantity in the vessel or pipe, as determined under paragraph (b) of 
this section, is spilled instantaneously to form a liquid pool. For 
liquids at temperatures below their atmospheric boiling point, the 
volatilization rate shall be calculated at the conditions specified in 
paragraph (d) of this section.
    (2) The owner or operator shall assume that the quantity which 
becomes vapor in the first 10 minutes is involved in the vapor cloud 
explosion.
* * * * *
[FR Doc. 99-12936 Filed 5-24-99; 10:57 am]
BILLING CODE 6560-50-P