[Federal Register Volume 87, Number 59 (Monday, March 28, 2022)]
[Proposed Rules]
[Pages 17890-17935]
[FR Doc No: 2022-05505]

Vol. 87

Monday,

No. 59

March 28, 2022

Part III

Securities and Exchange Commission

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40 CFR Parts 118 and 300

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Clean Water Act Hazardous Substance Worst Case Discharge Planning
Regulations; Proposed Rule

Federal Register / Vol. 87 , No. 59 / Monday, March 28, 2022 /
Proposed Rules

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 118 and 300

[EPA-HQ-OLEM-2021-0585; FRL-7881-02-OLEM]
RIN 2050-AH17

Clean Water Act Hazardous Substance Worst Case Discharge Planning
Regulations

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The Clean Water Act (CWA) states that regulations shall be
issued which require an owner or operator of a facility to prepare and
submit a plan for responding, to the maximum extent practicable, to a
worst case discharge, and to a substantial threat of such a discharge,
of a hazardous substance. The Environmental Protection Agency (EPA or
Agency) proposes to require planning for worst case discharges of CWA
hazardous substances for onshore non-transportation-related facilities
that could reasonably be expected to cause substantial harm to the
environment by discharging CWA hazardous substances into or on the
navigable waters, adjoining shorelines, or exclusive economic zone.

DATES: Comments must be received on or before May 27, 2022.

ADDRESSES: You may send comments, identified by Docket ID No. EPA-HQ-
OLEM-2021-0585, by any of the following methods:
-- Federal eRulemaking Portal: https://www.regulations.gov/ (our
preferred method). Follow the online instructions for submitting
comments.
-- Mail: U.S. Environmental Protection Agency, EPA Docket Center, EPA-
HQ-OLEM-2021-0585 Docket, Mail Code 28221T, 1200 Pennsylvania Avenue
NW, Washington, DC 20460.
-- Hand delivery or courier (by scheduled appointment only): EPA Docket
Center, WJC West Building, Room 3334, 1301 Constitution Avenue NW,
Washington, DC 20004. The Docket Center's hours of operations are 8:30
a.m. to 4:30 p.m., Monday through Friday (except Federal holidays).
    Instructions: All submissions received must include the Docket ID
No. for this rulemaking. Comments received may be posted without change
to https://www.regulations.gov/, including any personal information
provided. For detailed instructions on sending comments and additional
information on the rulemaking process, see the ``Public Participation''
heading of the SUPPLEMENTARY INFORMATION section of this document. Out
of an abundance of caution for members of the public and our staff, the
EPA Docket Center and Reading Room are open to the public by
appointment only to reduce the risk of transmitting COVID-19. Our
Docket Center staff also continues to provide remote customer service
via email, phone, and webform. Hand deliveries and couriers may be
received by scheduled appointment only. For further information on EPA
Docket Center services and the current status, please visit us online
at https://www.epa.gov/dockets.

FOR FURTHER INFORMATION CONTACT: Rebecca Broussard, Office of Emergency
Management, Mail Code 5104A, Environmental Protection Agency, 1200
Pennsylvania Avenue NW, Washington, DC 20460; telephone number: 202-
564-6706; email: [email protected].

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Public Participation
    A. Written Comments
II. General Information
    A. Does this action apply to me?
    B. What action is the Agency taking?
    C. What is the Agency's authority for taking this action?
    D. What are the costs and benefits of this action?
    E. List of Abbreviations and Acronyms
III. Background
    A. Statutory Authority and Delegation of Authority
     1. Statutory Requirements
     2. Delegation of Authority
    B. CWA Hazardous Substance Designation and Reportable Quantities
    C. Regulatory Background
     1. EPA CWA Hazardous Substance Actions
     2. EPA Oil Pollution Prevention Regulation
     3. USCG CWA Hazardous Substance Worst Case Discharge Actions
    D. Litigation
    E. CWA Hazardous Substance Discharge History and Impacts
Analysis
     1. Discharge History and Reported Impacts
     2. Most Frequently Discharged CWA Hazardous Substances
     3. Impacts to Waterways and Sensitive Environments
     4. NRC Data Limitations
     5. Data Sources Examined
    F. Analysis of Existing Regulatory Programs
IV. Proposed Action
    A. Applicability Criteria
     1. Screening Criteria
     2. Substantial Harm Criteria
     3. Other Applicability Criteria
     4. Worst Case Discharge Calculations
     5. Substantial Harm Certification Form
    B. Response Planning
     1. Consistency With NCP and ACPs
     2. LEPC or TEPC Coordination
     3. QI Designation and Duties
     4. CWA Hazardous Substance FRP Components
    C. Implementation and Enforcement
     1. Office Delegation
     2. Compliance Dates
     3. Confidential Business Information
     4. Appeals Process
     5. Stakeholder Petitions
     6. Consistency With the NCP
    D. Additional Considerations
     1. Communities With Environmental Justice Concerns
     2. Climate Change
     3. Facility Density
V. Statutory and Executive Orders Reviews
    A. Executive Order 12866: Regulatory Planning and Review and
Executive Order 13563: Improving Regulation and Regulatory Review
    B. Paperwork Reduction Act (PRA)
    C. Regulatory Flexibility Act (RFA)
    D. Unfunded Mandates Reform Act (UMRA)
    E. Executive Order 13132: Federalism
    F. Executive Order 13175: Consultation and Coordination With
Indian Tribal Governments
    G. Executive Order 13045: Protection of Children From
Environmental Health Risks and Safety Risks
    H. Executive Order 13211: Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution or Use
    I. National Technology Transfer and Advancement Act (NTTAA)
    J. Executive Order 12898: Federal Actions To Address
Environmental Justice in Minority Populations and Low-Income
Populations

I. Public Participation

A. Written Comments

    Submit your comments, identified by Docket ID No. EPA-HQ-OLEM-2021-
0585 at https://www.regulations.gov (our preferred method), or the
other methods identified in the ADDRESSES section, above. Once
submitted, comments cannot be edited or removed from the docket. The
EPA may publish any comment received to its public docket. Do not
submit to EPA's docket at https://www.regulations.gov any information
you consider to be Confidential Business Information (CBI) or other
information whose disclosure is restricted by statute. Multimedia
submissions (audio, video, etc.) must be accompanied by a written
comment. The written comment is considered the official comment and
should include discussion of all points you wish to make. The EPA will
generally not consider comments or comment contents located outside of
the primary submission (i.e., on the web, cloud, or other file sharing
system). For additional submission methods, the full

EPA public comment policy, information about CBI or multimedia
submissions, and general guidance on making effective comments, please
visit https://www.epa.gov/dockets/commenting-epa-dockets.
    Due to public health concerns related to COVID-19, the EPA Docket
Center and Reading Room are open to the public by appointment only. Our
Docket Center staff also continues to provide remote customer service
via email, phone, and webform. Hand deliveries or couriers will be
received by scheduled appointment only. For further information and
updates on EPA Docket Center services, please visit us online at
https://www.epa.gov/dockets.
    The EPA continues to carefully and continuously monitor information
from the Centers for Disease Control and Prevention (CDC), local area
health departments, and our Federal partners so that the Agency can
respond rapidly as conditions change regarding COVID-19.

II. General Information

A. Does this action apply to me?

    A list of NAICS codes at the three-digit level that could be
affected by requirements established under CWA section 311(j)(5) is
provided in Table 1:

       Table 1--Entities Potentially Affected by the Proposed Rule
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                                             North American industry
                NAICS 3                   classification system (NAICS)
                                                   description
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111....................................  Crop Production
115....................................  Support Activities for
                                          Agriculture and Forestry
211....................................  Oil and Gas Extraction
212....................................  Mining (except Oil and Gas)
213....................................  Support Activities for Mining
221....................................  Utilities
311....................................  Food Manufacturing
314....................................  Textile Product Mills
321....................................  Wood Product Manufacturing
322....................................  Paper Manufacturing
324....................................  Petroleum and Coal Products
                                          Manufacturing
325....................................  Chemical Manufacturing
326....................................  Plastics and Rubber Products
                                          Manufacturing
327....................................  Nonmetallic Mineral Product
                                          Manufacturing
331....................................  Primary Metal Manufacturing
332....................................  Fabricated Metal Product
                                          Manufacturing
333....................................  Machinery Manufacturing
335....................................  Electrical Equipment,
                                          Appliance, and Component
                                          Manufacturing
336....................................  Transportation Equipment
                                          Manufacturing
423....................................  Merchant Wholesalers, Durable
                                          Goods
424....................................  Merchant Wholesalers,
                                          Nondurable Goods
441....................................  Motor Vehicle and Parts Dealers
444....................................  Building Material and Garden
                                          Equipment and Supplies Dealers
447....................................  Gasoline Stations
453....................................  Miscellaneous Store Retailers
488....................................  Support Activities for
                                          Transportation
493....................................  Warehousing and Storage
511....................................  Publishing Industries (except
                                          internet)
522....................................  Credit Intermediation and
                                          Related Activities
562....................................  Waste Management and
                                          Remediation Services
611....................................  Educational Services
622....................................  Hospitals
811....................................  Repair and Maintenance
812....................................  Personal and Laundry Services
928....................................  National Security and
                                          International Affairs
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    This table is not intended to be exhaustive, but rather provides a
likely minimal set of affected entities likely to be regulated by this
action. This table lists the types of entities that EPA is aware could
potentially be subject to this proposed action. Other types of entities
not listed in the table may also be subject to this proposed action. To
determine whether your facility is subject to this proposed action, you
should carefully examine the applicability criteria proposed in Sec.
118.3. If you have questions regarding the applicability of this action
to a particular entity or facility, consult the person listed in the
FOR FURTHER INFORMATION CONTACT section.

B. What action is the Agency taking?

    The EPA is proposing new requirements for Facility Response Plans
(FRPs) for worst case discharges of CWA hazardous substances for
onshore facilities that, because of their location, could reasonably be
expected to cause substantial harm to the environment by discharging
into or on the navigable waters, adjoining shorelines, or exclusive
economic zone.

C. What is the Agency's authority for taking this action?

    This proposal is authorized by section 311(j)(5) and 501(a) of the
CWA, (33 U.S.C. 1321(j)(5), 1361(a)).

D. What are the costs and benefits of this action?

    EPA estimated the total costs of the proposed action by combining
the per-facility estimates of compliance costs with the estimate of the
affected facility universe. EPA estimated the annualized cost of the
proposed rule over a 20-year analysis period, using three percent and
seven percent discount rates, as presented in Table 2.

       Table 2--Total Compliance Cost of the Proposed Action, 20-Year Present Value and Annualized ($2020)
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                                        Present value,    Annualized cost,    Present value,    Annualized cost,
                                              7%                 7%                 3%                 3%
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Cost................................       $300,375,193        $28,353,293       $410,322,776        $27,580,136
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    EPA also estimated the annualized cost of the proposed action to
EPA to develop and implement the proposed requirements, which can be
found in the Regulatory Impact Analysis (RIA) titled, ``Regulatory
Impact Analysis: Clean Water Act Hazardous Substance Worst Case
Discharge Planning Regulations,'' available in the docket for this
action. The proposed action is expected to have a mitigating effect on
CWA hazardous substance worst case discharges because the proposed rule
provisions address the kind of damages and adverse impacts expected
from this type of discharge. The planning activities associated with
developing CWA hazardous substance FRPs are likely to mitigate several
damage categories through pre-discharge planning and identification of
potential receptors and applicable endpoints; the emergency response
information provisions; descriptions of discharge detection systems,
hazard evaluation, and training programs; and drills and exercises.
Information on previous worst case discharges of a similar nature
suggests that the benefits of mitigating these

discharges could be large relative to the proposed rule's estimated
cost.
    Sections 6 and 7 of the RIA developed for this proposed action
provide additional details on costs and benefits, respectively, and EPA
solicits comment on the contents therein and associated data sources.

E. List of Abbreviations and Acronyms

ACP Area Contingency Plan
AEGLs Acute Exposure Guideline Levels for Airborne Chemicals
ANPRM Advanced Notice of Proposed Rulemaking
APA Administrative Procedures Act
AWIA America's Water Infrastructure Act
BHP Biodegradation, Hydrolysis, and Photolysis
CAA Clean Air Act
CASRN Chemical Abstract Service Registry Numbers
CBI Confidential Business Information
CCC Criterion Continuous Concentration
CDC Centers for Disease Control and Prevention
CFR Code of Federal Regulations
CMC Criterion Maximum Concentration
CERCLA Comprehensive Environmental Response, Compensation, and
Liability Act of 1980
CFATS Chemical Facility Anti-Terrorism Standards
CTAC Chemical Transportation Advisory Committee
CWA Clean Water Act
DHS United States Department of Homeland Security
DOI United States Department of the Interior
DOT United States Department of Transportation
EJSCREEN Environmental Justice Screening and Mapping Tool
E.O. Executive Order
EPA United States Environmental Protection Agency
EPCRA Emergency Planning and Community Right-to-Know Act
ERAP Emergency Response Action Plan
ERPGs Emergency Response Planning Guidelines
FR Federal Register
FRP Facility Response Plan
FWSE Fish, Wildlife, and Sensitive Environments
HAZWOPER Hazardous Waste Operations and Emergency Response
ICR Information Collection Request
ICS Incident Command System
IDLH Immediately Dangerous to Life or Health
IRIS Integrated Risk Information System
LC50 Lethal Concentration 50%
LD50 Lethal Dose 50%
LEPC Local Emergency Planning Committee
MCL Maximum Contaminant Level
MOU Memorandum of Understanding
MRLs Minimum Risk Levels
MSHA Mine Safety and Health Administration
MTR Marine Transportation Related
NAICS North American Industry Classification System
NCP National Contingency Plan
NIIMS National Interagency Incident Management System
NIOSH National Institute for Occupational Safety and Health
NOAA National Oceanic and Atmospheric Administration
NPDES National Pollutant Discharge Elimination System
NPRM Notice of Proposed Rulemaking
NRC National Response Center
NTSIP National Toxic Substance Incidents Program
NTTAA National Technology Transfer and Advancement Act
OMB Office of Management and Budget
OPA 90 Oil Pollution Act of 1990
OSC On-Scene Coordinator
OSHA Occupational Safety and Health Administration
OSRO Oil Spill Removal Organization
PALs Provisional Advisory Levels for Hazardous Agents
PCBs Polychlorinated Biphenyls
PHMSA Pipeline and Hazardous Materials Safety Administration
PRA Paperwork Reduction Act
PREP Preparedness for Response Exercise Program
QI Qualified Individual
RA Regional Administrator
RCP Regional Contingency Plan
RCRA Resource Conservation and Recovery Act
RFA Regulatory Flexibility Act
RIA Regulatory Impact Analysis
RMP Risk Management Plan
RQ Reportable Quantity
SBA Small Business Administration
SDWA Safe Drinking Water Act
SERC State Emergency Response Commission
SMCRA Surface Mining Control and Reclamation Act
SPCC Spill Prevention Control, and Countermeasure
SRO Spill Response Organization
SWPA Source Water Protection Area
TBD Technical Background Document
TEPC Tribal Emergency Planning Committee
TERC Tribal Emergency Response Commission
TRI Toxics Release Inventory
TSCA Toxic Substances Control Act of 1976 as amended by the
Lautenberg Act
TSDF Treatment, Storage, and Disposal Facility
UMRA Unfunded Mandates Reform Act
USCG United States Coast Guard
UST Underground Storage Tank

III. Background

A. Statutory Authority and Delegation of Authority

1. Statutory Requirements
    The CWA as amended by the Oil Pollution Act of 1990 (33 U.S.C. 2701
et seq; hereafter, ``OPA 90''), states, ``The President shall issue
regulations which require an owner or operator of a tank vessel or
facility . . . to prepare and submit to the President a plan for
responding, to the maximum extent practicable, to a worst case
discharge, and to a substantial threat of such a discharge, of oil or a
hazardous substance'' (33 U.S.C. 1321(j)(5)(A)(i)). For this action, a
facility is determined to be ``. . . [an] onshore facility that,
because of its location, could reasonably be expected to cause
substantial harm to the environment by discharging into or on the
navigable waters,\1\ adjoining shorelines, or the exclusive economic
zone'' (33 U.S.C. 1321(j)(5)(C)(iv)). As described below, the
Administrator has been delegated this authority under E.O. 12777 (56 FR
54757, October 18, 1991). The Administrator also has authority under
CWA section 501 to prescribe such regulations as are necessary to carry
out provisions of the Act. In 33 U.S.C. 1321(j)(5)(D), the CWA states
that these response plans must:
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    \1\ Navigable waters are defined in 40 CFR 120.2 as waters of
the United States, including the territorial seas. This document
will refer to ``navigable water'' to include ``adjoining shorelines
and the exclusive economic zone.''
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    (1) Be consistent with the National Contingency Plan (NCP) and Area
Contingency Plans (ACP);
    (2) Identify the qualified individual (QI) having full authority to
implement removal actions, and require immediate communications between
that individual and the appropriate Federal official and the persons
providing personnel and equipment;
    (3) Identify, and ensure by contract or other means approved by the
President the availability of private personnel and equipment necessary
to remove to the maximum extent practicable a worst case discharge
(including a discharge resulting from fire or explosion), and to
mitigate or prevent a substantial threat of such a discharge;
    (4) Describe the training, equipment testing, periodic unannounced
drills, and response actions of persons on the vessel or at the
facility, to be carried out under the plan to ensure the safety of the
vessel or facility and to mitigate or prevent the discharge, or the
substantial threat of a discharge;
    (5) Be updated periodically; and
    (6) Be resubmitted for approval of each significant change.
    EPA's responsibilities in the CWA (33 U.S.C. 1321(j)(5)(E)) for
this action for onshore facilities that could reasonably be expected to
cause significant and substantial harm to the environment by
discharging into or on the navigable waters are to:
    (1) Promptly review plans;
    (2) Require amendments when plans do not meet the statutory
requirements;
    (3) Approve plans; and
    (4) Review each plan periodically.
    Additionally, EPA may require inspection of containment booms,

skimmers, vessels, and other major equipment used to remove discharges
(33 U.S.C. 1321(j)(6)(A)). EPA also has the authority to conduct
unannounced drills of removal capability in areas for which Area
Contingency Plans (ACPs) are required and under relevant FRPs (33
U.S.C. 1321(j)(7)).
2. Delegation of Authority
    Under E.O. 12777 (56 FR 54757, October 18, 1991), EPA was delegated
the authority to regulate non-transportation-related onshore facilities
and non-transportation-related offshore facilities landward of the
coastline.\2\ DOT was the delegated authority for transportation-
related facilities and the U.S. Coast Guard (USCG) was delegated the
authority for tank vessels and marine transportation-related (MTR)
facilities. Section 2(i) of E.O. 12777 allows for further delegation
between the agencies as later occurred in a February 3, 1994 MOU
between EPA, the U.S. Department of the Interior (DOI), and DOT (59 FR
9494, February 28, 1994). DOI redelegated 33 U.S.C. 1321(j)(5)
authority to regulate non-transportation-related offshore facilities
landward of the coastline to EPA. This MOU applies to both oil and CWA
hazardous substance facilities.
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    \2\ E.O. 12777 Implementation of Section 311 Of The Federal
Water Pollution Control Act of October 18, 1972, as Amended, and the
Oil Pollution Act of 1990. See https://www.archives.gov/federal-register/executive-orders/1991.html#12777.
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    EPA has delegated authority over offshore facilities landward of
the coastline as per 40 CFR part 112 Appendix B. However, this action
is limited to non-transportation-related onshore facilities as defined
in the consent decree described in Section III.D of this document. EPA
solicits data, information, and comment on CWA hazardous substance
facilities located offshore landward of the coastline and their
regulation under this action.

B. CWA Hazardous Substance Designation and Reportable Quantities

    The term ``hazardous substance'' is defined in the CWA as those
substances designated pursuant to 33 U.S.C 1321(b)(2), wherein EPA is
authorized to list hazardous substances which, when discharged in any
quantity into jurisdictional waters, present an imminent and
substantial danger to public health or welfare, including, but not
limited to, fish, shellfish, wildlife, shorelines, and beaches (33
U.S.C. 1321(a)(14)).
    Once a chemical (i.e., ``element and compound'') is designated as a
CWA hazardous substance, the reportable quantity is established by
regulation under 33 U.S.C. 1321(b)(4). Section 311 of the CWA prohibits
discharges of CWA hazardous substances in quantities that may be
harmful into navigable waters and waters of the contiguous zone, except
where permitted under the Protocol of 1978 relating to the
International Convention for the Prevention of Pollution from Ships,
1973,\3\ and where permitted in quantities and at times and locations
or under such circumstances or conditions as the President may, by
regulation, determine not to be harmful (33 U.S.C 1321(b)(3)).
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    \3\ Protocol of 1978 relating to the International Convention
for the prevention of pollution from ships, 1973 (with annexes,
final act and International Convention of 1973). Concluded at London
on 17 February 1978; registered by the International Maritime
Organization on 26 November 1983. https://treaties.un.org/doc/Publication/UNTS/Volume%201340/volume-1340-A-22484-English.pdf.
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C. Regulatory Background

1. EPA CWA Hazardous Substance Actions
    EPA designated a list of CWA hazardous substances in 40 CFR part
116 \4\ and subsequently established reportable quantities (RQs) for
those substances in 40 CFR part 117, the discharge of which at or above
the RQ is a violation of CWA section 311(b)(3) and requires notice,
including notice as set forth in 40 CFR 117.21 and the National
Contingency Plan in 40 CFR 300.125(a).\5\ The RQs constitute the
quantities EPA deemed may be harmful and were initially based on a
five-level rating system derived from acute aquatic toxicity and set in
40 CFR 117.3. The most acutely toxic CWA hazardous substances were
classified as Category X and assigned a one-pound RQ, which was
determined based on the smallest container commonly used in
commerce.\6\ Under EPA's scaled system, EPA assigned the other
categories on a proportional basis. If the upper aquatic toxicity limit
of a category is 10 times the upper limit of the preceding, more toxic
category, then the harmful quantity was set as 10 times larger,
excepting category D, at five times larger, and so forth. CWA RQs (in
lbs.) for the five categories are X: 1, A: 10, B: 100, C: 1,000, and D:
5,000.
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    \4\ 43 FR 10474, March 13, 1978.
    \5\ 44 FR 50766, August 29, 1979.
    \6\ 43 FR 10496, March 13, 1978.
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2. EPA Oil Pollution Prevention Regulation
    Promulgated under the authority of CWA section 311, the Oil
Pollution Prevention regulation sets forth requirements for the
prevention of, preparedness for, and response to oil discharges at
specific non-transportation-related facilities (see 40 CFR part 112).
The goal of the regulation is to prevent discharges of oil and oil
mixed with hazardous substances from onshore facilities and to contain
such discharges. The regulation requires facilities to develop and
implement Spill Prevention, Control, and Countermeasure (SPCC) Plans
and establishes procedures, methods, and equipment requirements to
prevent oil discharges to navigable waters or adjoining shorelines.
    Additionally, subpart D of the Oil Pollution Prevention regulation
requires certain facility owners or operators to prepare and submit a
facility response plan (FRP) for responding to a worst case discharge
of oil. The Oil Pollution Prevention FRP requirements apply to a subset
of SPCC-regulated facilities from which a discharge, or substantial
threat of discharge, may cause substantial harm to the environment.\7\
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    \7\ See 40 CFR part 112 Appendix C.
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3. USCG CWA Hazardous Substance Worst Case Discharge Actions
    In response to OPA 90, the USCG published rulemaking actions
regarding response plans for CWA hazardous substances. On May 3, 1996,
the USCG published an Advance Notice of Proposed Rulemaking (ANPRM)
addressing vessel and facility response plans (61 FR 20084, May 3,
1996). USCG held two public meetings in 1996 and then developed
proposed regulations and published two separate NPRMs for tank vessels
and MTR facilities in 1999 (64 FR 13734, March 22, 1999) and 2000 (65
FR 17416, March 31, 2000), respectively. On February 17, 2011, USCG
reopened the comment period. In 2019, USCG withdrew their proposed
rulemakings (84 FR 2799 and 84 FR 2800, February 8, 2019) based on
findings of the Chemical Transportation Advisory Committee (CTAC) that
the proposed rules are no longer applicable to the current state of
chemical industry spill response. Specifically for MTR facilities,
``[d]ue to the services and requirements industry frequently engages in
to satisfy insurance requirements and company sustainability polices,
together with the existence of new terminal inspection protocols like
that developed by the Chemical Distribution Institute, CTAC was unable
to identify any significant gaps in hazardous substance spill response
planning at marine transportation-related facilities that would be
reduced by the 2000 proposed rulemaking'' (84 FR 2799-2800).

Additionally, for vessels, ``CTAC also identified many areas in which
the NPRM may overlap with existing local, state, and international
regulatory schemes as well as current industry practice'' (84 FR 2799).
To date, a USCG regulation has not been finalized.

D. Litigation

    On March 21, 2019, the Natural Resources Defense Council, on behalf
of Clean Water Action and the Environmental Justice Health Alliance for
Chemical Policy Reform filed suit in the United States District Court
for the Southern District of New York alleging violations of CWA
311(j)(5)(A)(i) and the Administrative Procedures Act (APA).\8\ The
first claim alleged that EPA's failure to issue ``regulations mandated
by the [CWA] requiring non-transportation-related substantial-harm
facilities to plan, prevent, mitigate and respond to worst case spills
of hazardous substances . . . constitutes a failure to perform a non-
discretionary duty or act in violation of the [CWA].'' The second claim
alleged that, ``EPA's failure to issue these regulations constitute[d]
agency action unlawfully withheld contrary to and in violation of the
[APA] and the [CWA].'' The plaintiffs requested an order from the Court
to compel EPA to promulgate CWA Hazardous Substance Worst Case
Discharge Planning Regulations. Following EPA's Answer, filed on June
4, 2019, the plaintiffs and EPA entered discussions regarding a
potential resolution of the lawsuit.
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    \8\ Complaint for Declaratory and Injunctive Relief,
Environmental Justice Health Alliance for Chemical Policy Reform v.
EPA, No. 1-19-cv-02516 (S.D.N.Y., filed March 21, 2019).
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    The plaintiffs and EPA entered into a consent decree on March 12,
2020 that resolved the litigation.\9\ The consent decree requires that
within two years (24 months) of entry into the consent decree, or by
March 12, 2022, EPA will sign a notice of proposed rulemaking
pertaining to the issuance of the CWA Hazardous Substance Worst Case
Discharge Planning Regulations for non-transportation-related onshore
facilities. The consent decree further requires EPA to sign a notice
taking final action within an additional two and a half years, or 30
months after publication of the proposal. This proposed action
satisfies EPA's first obligation under the consent decree.
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    \9\ Envtl. Justice Health All. for Chem. Reform v. EPA, No.
1:19-cv-02516-VM, Document 32 (S.D.N.Y., filed March 12, 2020).
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E. CWA Hazardous Substance Discharge History and Impacts Analysis

    To gain a historic perspective of CWA hazardous substance
discharges to water over time, EPA researched and analyzed multiple
sources of available CWA hazardous substance discharge data. EPA
analyzed National Response Center (NRC) data on CWA hazardous
substances discharges to water. 40 CFR 117.21 requires immediate
notification to the NRC once the person in charge of a vessel or an
offshore or onshore facility has knowledge of a discharge of a CWA
hazardous substance from the facility in quantities equal to or
exceeding its assigned RQ in any 24-hour period. Reporters may not
always be familiar with RQ levels for CWA hazardous substances and
reported quantities released are usually inaccurate or unknown, the NRC
will field and process all reported CWA hazardous substance incidents
and forward the initial information to the Federal On-Scene Coordinator
(OSC) for further investigation. Reports are also made under the NCP
reporting requirement in 40 CFR 300.125. NRC data are generated by
notifications received immediately following a discharge and often lack
complete information on chemicals and quantities discharged, incident
and response details, impacts, and locations. Although the data have
limitations of accuracy, completeness, and over- and under-reporting of
incidents, the NRC database is the most comprehensive database for CWA
hazardous substance discharges. It is important to recognize that these
data reflect the impacts reported upon discovery of an incident (e.g.,
evacuations, injuries, hospitalizations, fatalities, waterway closures,
and water supply contamination), which often result directly from the
event that caused the discharge, rather than the totality of impacts
that could be attributed to the discharge itself. In many cases, it can
take days, weeks, and even months to fully characterize the harm caused
by a discharge. NRC data are not updated to reflect that harm. This
analysis is also hindered by the lack of a robust national database of
the types of CWA hazardous substance discharges that EPA is proposing
to regulate in this action.
1. Discharge History and Reported Impacts
    While there are notable instances of high-volume discharges of non-
CWA hazardous substances to water, EPA found limited data on historical
worst cases discharges to water of CWA-regulated hazardous substances
and the NRC has no information related to the origination of the data
cited in this section and Table 3. Between 2010 and 2019, 252,238 total
discharges were reported to the NRC. Of those, 98,306 were non-
transportation-related, of which CWA hazardous substance discharges
comprised 19,657. EPA then identified 2,489 non-transportation-related
CWA hazardous substance discharges which either reached water (1,311)
or it is unknown whether they reached water (1,178). Of the 2,489
discharges in those categories, 131 had reported impacts. Finally, of
those 131, EPA identified 52 discharges of CWA-regulated hazardous
substances that could be linked to non-transportation-related
facilities (i.e., within EPA's regulatory jurisdiction). Given the
generally cursory nature of data provided to the NRC as part of an
emergency notification, the Agency was unable to determine whether any
of the 52 discharges could have been considered worst case discharges
(i.e., the largest foreseeable discharge in adverse weather conditions,
including a discharge resulting from fire or explosion; see Section
IV.A.3.b of this preamble) of CWA hazardous substances based on volume
and impacts.\10\
---------------------------------------------------------------------------

    \10\ The NRC database does not identify how many of the 2,489
discharges involving a CWA hazardous substance reached or may have
reached navigable waters. For this analysis, EPA took a conservative
approach and assumed that all discharges impacted navigable water.
---------------------------------------------------------------------------

    Over the 10-year period of 2010 to 2019, the average number of CWA
hazardous substance discharges declined from 289 to 219 discharges (a
decrease of 24 percent). EPA has no information as to the cause of this
decline.
2. Most Frequently Discharged CWA Hazardous Substances
    A chart of the distribution by CWA hazardous substance of the 2,489
CWA hazardous substance discharges that may have reached water is shown
in Table 3.

 Table 3--Distribution of Discharges by CWA Hazardous Substance 2010 to
                                  2019.
------------------------------------------------------------------------
                                                            Discharged
                 CWA Hazardous substance                     (percent)
------------------------------------------------------------------------
PCBs....................................................              55
Sulfuric acid...........................................               8
Sodium hydroxide........................................               6
Ammonia.................................................               5
Benzene.................................................               4
Hydrochloric acid.......................................               4
Chlorine................................................               4
Sodium hypochlorite.....................................               3

Other...................................................              12
------------------------------------------------------------------------
Source: NRC.

    The majority of discharges (55 percent, or 1,358) comprised
polychlorinated biphenyls (PCBs), typically PCB-containing transformer
leaks or discharges, most often due to vehicles colliding with
transformers (most likely on telephone poles). Fifteen chemicals
accounted for 90 percent of CWA hazardous substance discharge incidents
(by frequency, not by volume), 263 of 362 CWA hazardous substances
(includes alternate names) had no reported discharges, and 80 CWA
hazardous substances had fewer than 10 discharges.
    EPA banned PCBs in 1979 and while they are no longer commercially
produced, they are still present in materials and products produced
before the ban. EPA regulates PCBs through the Toxic Substances Control
Act of 1976 (TSCA). Implementation of TSCA includes a PCB cleanup
policy which addresses mitigating the impacts of PCB discharges.
Additionally, most PCBs discharges or threats of discharges are
comingled with oil. Oil of any kind and in any form, including oil
mixtures, are subject to regulation under EPA's Oil Pollution
Prevention regulation. Please see the Technical Background Document
(TBD) for additional information.
3. Impacts to Waterways and Sensitive Environments
    In reviewing the identified 131 non-transportation-related CWA
hazardous substance discharges that may have reached water with
reported impacts, EPA determined that 46 involved residences, dumping,
third-party damage to transformers (typically vehicle crashes),
swimming pools, drills or exercises (not actual discharges), vehicles,
incidents that occurred outside of the time period (pre-2010) but were
reported later, duplicates, incidents outside of the United States, or
miscellaneous hydraulic fracturing reports (e.g., odor coming from tap
due to drilling occurring nearby).
    Of the remaining 86 discharges, 52 could be linked to non-
transportation-related facilities that are within EPA's regulatory
jurisdiction. Of note:

--Water supply contamination: 50 incidents (six discharges reached
water, 44 discharges where it is unknown if discharges reached water
\11\)
---------------------------------------------------------------------------

    \11\ Indicator in NRC database for water contamination provides
options of yes, no, and unknown to have reached water. Forty-four of
these incidents reported `unknown' if reached water. The data are
unclear as to whether any of these incidents reached water and/or
whether they contaminated the water.
---------------------------------------------------------------------------

--Waterway traffic corridor closed: Two incidents (one discharge
reached water, one discharge where it is unknown if the discharge
reached water)

    Other impacts,\12\ to the extent to which known, are described in
Table 4. Since the NRC fields and processes initial incident
information, impact information cited in Table 4 is most often unknown.
---------------------------------------------------------------------------

    \12\ No fatalities resulted from a CWA hazardous substance
discharge. The only fatality identified was due to a tractor trailer
collision on a bridge where the driver perished, and the vehicle
landed on the toe of a temporary cap on an EPA Superfund site.

Table 4--Other Reported Impacts of CWA Hazardous Substance Discharges From Non-Transportation-Related Facilities
                                    That May Have Reached Water 2010 to 2019
----------------------------------------------------------------------------------------------------------------
                                             Number of
         Other reported impacts              incidents       Number of individuals               Notes
----------------------------------------------------------------------------------------------------------------
Evacuations.............................              35  1,115.....................  Typically impacts facility
                                                                                workers.
Shelter-in-place........................               1  No data available.........  Barge offloading toluene
                                                                                discharged 50 gallons
                                                                                into the Mississippi
                                                                                River.
Injuries (without hospitalizations).....               2  4.........................  All reported injuries
                                                                                appear to be workers
                                                                                onsite, but NRC data are
                                                                                not explicit.
Hospitalizations........................              11  18........................  All reported
                                                                                hospitalizations appear
                                                                                to be workers onsite, but
                                                                                NRC data are not
                                                                                explicit.
----------------------------------------------------------------------------------------------------------------

4. NRC Data Limitations
    The NRC data on which EPA relied for this analysis have numerous
limitations. As described in the subsequent section, EPA has not been
able to identify another dataset which is more complete and/or includes
the types of discharges that would be regulated by this proposed rule,
so despite their limitations, EPA is using the NRC data for this
analysis. There may be impacts (i.e., additional or other than
evacuations, injuries, hospitalizations, fatalities, waterway closures,
and water supply contamination) from the universe of CWA hazardous
substance discharges to jurisdictional water from non-transportation-
related facilities which were not reported to the NRC and, thus, could
not be quantified in this analysis. These may include the loss of
productivity due to a facility or process unit shutting down because of
a discharge, emergency response and restoration costs, transaction
costs such as the cost of resulting litigation, damages to water
quality, fish kills, or impacts to property values due to changes in
perceived risk or reduced ecological services. EPA was not able to
identify data sources to quantify these impacts, other than the cited
data from the NRC. The NRC data are discussed and analyzed further in
the RIA.
5. Data Sources Examined
    Since the mission of the NRC is to be the initial point of contact
for all oil and hazardous substances releases and forward that
information to the Federal OSC for response, the initial data collected
does, in most cases, have limitations. Due to this lack of information
on discharges with impacts in the NRC database, EPA examined additional
data sources including:

--National Oceanic and Atmospheric Administration (NOAA) Incident News
--Risk Management Plan (RMP) \13\ rule five-year accident history data
---------------------------------------------------------------------------

    \13\ Chemical Accident Prevention Provisions, RMP (40 CFR part
68).
---------------------------------------------------------------------------

--Toxics Release Inventory (TRI) discharge to water data

--Survey data from previous CWA Hazardous Substance Spill Prevention
rulemaking effort \14\
---------------------------------------------------------------------------

    \14\ EPA sent a voluntary survey to states, tribes and U.S.
territories in June 2018 as part of the final Clean Water Act
Hazardous Substances Spill Prevention rulemaking (84 FR 46100;
September 3, 2019) requesting information on the number and type of
EPCRA Tier II facilities reporting CWA hazardous substances onsite,
as well as information about historical discharges of CWA hazardous
substances, ecological and human health impacts of those discharges,
and existing state and tribal regulatory programs that serve to
prevent discharges of hazardous substances (Docket EPA-HQ-OLEM-2017-
0444).
---------------------------------------------------------------------------

--National Toxic Substance Incidents Program (NTSIP)
--Chemical Safety and Hazard Investigation Board Reports
--State discharge reports

    EPA did not identify any instances of worst case discharges of CWA
hazardous substances (i.e., the largest foreseeable discharge in
adverse weather conditions, including a discharge resulting from fire
or explosion, see Section IV.A.3.b of this preamble) previously unknown
to the Agency from the above list of data sources. The RIA contains
additional information on these data sources and EPA's research to
identify discharge information sources. EPA requests data on
occurrences of CWA hazardous substance discharges into navigable waters
along with documented impacts.

F. Analysis of Existing Regulatory Programs

    To understand the degree to which CWA hazardous substances worst
case discharge planning requirements are regulated under existing
regulations, the Agency reviewed and analyzed the current Federal and
state regulatory framework as well as industry standards for overlap
with and coverage of CWA hazardous substance worst case discharge FRP
provisions required by CWA section 311(j)(5) as detailed in Section III
of this preamble.
    EPA's analysis did not find any combination of Federal programs
that comprehensively cover all the CWA section 311(j)(5)(D)
requirements for all CWA hazardous substances. CWA hazardous substance
facilities subject to the Oil Pollution Prevention Program requirements
or RMP rule will have some overlap for the required program elements.
RCRA hazardous waste regulations are comprehensive for CWA hazardous
substances present as waste. State programs do not provide uniform
coverage and are a patchwork, while industry standards are voluntary.
    The TBD compares the programs analyzed to the CWA hazardous
substance FRP required program elements and provides a matrix of each
program examined and elements of those programs that have requirements
comparable to those in CWA section 311(j)(5).
    EPA analyzed the following EPA requirements:

--America's Water Infrastructure Act of 2018 Amendments to section 1433
of the Safe Drinking Water Act (42 U.S.C. 300i-2)
--Chemical Accident Prevention Provisions, RMP (40 CFR part 68)
--Emergency Planning and Community Right-to-Know Act:
    --Emergency Planning Notification and Emergency Release
Notification (40 CFR part 355)
    --Hazardous Chemical Reporting: Community Right-to-Know (40 CFR
part 370)
    --Toxic Chemical Release Reporting: Community Right-to-Know (40 CFR
part 372)
--National Pollutant Discharge Elimination System (NPDES) Regulations
    --NPDES (40 CFR part 122)
    --General Pretreatment Regulations for Existing and New Sources of
Pollution (40--CFR part 403)
--Oil Pollution Prevention Regulations
    --Subpart A, Applicability, Definitions, and General Requirements
for All Facilities and All Types of Oils, SPCC (40 CFR part 112)
    --Subpart D, Response Requirements, FRP (40 CFR 112.20 and 112.21)
--Pesticide Regulations
    --Pesticide Management and Disposal (40 CFR part 165)
    --Pesticide Agricultural Worker Protection Standard (40 CFR part
170)
--Resource Conservation and Recovery Act (RCRA) Regulations
    --Criteria for Classification of Solid Waste Disposal Facilities
and Practices Subpart D, Standards for the Disposal of Coal Combustion
Residuals in Landfills and Surface Impoundments (40 CFR part 257)
    --Standards Applicable to Generators of Hazardous Wastes (40 CFR
part 262)
    --Standards for Owners and Operators of Hazardous Waste Treatment,
Storage, and Disposal Facilities (TSDF) (40 CFR parts 264 & 265)
    --Technical Standards and Corrective Action Requirements for Owners
and Operators of Underground Storage Tanks (UST) (40 CFR part 280)
--TSCA: PCBs Manufacturing, Processing, Distribution in Commerce, and
Use Prohibitions (40 CFR part 761)
    EPA also analyzed the following non-EPA Federal requirements:
--Mine Safety and Health Administration (MSHA) Subchapter H--Education
and Training, Subchapter I--Accidents, Injuries, Illnesses, Employment,
and Production in Mines (30 CFR parts 46-50)
--Occupational Safety and Health Administration Regulations:
    --Hazard Communication Standard (HazCom) (29 CFR 1910.1200)
    --Hazardous Waste Operations and Emergency Response (HAZWOPER) (29
CFR 1910.120)
    --Process Safety Management of Highly Hazardous Chemicals (29 CFR
1910.119)
    --Emergency Action Plan (29 CFR 1910.38)
--Pipeline and Hazardous Materials Safety Administration (PHMSA)
Hazardous Materials Regulations (49 CFR parts 171-179)
--Surface Mining Control and Reclamation Act (SMCRA) Mineral Resources,
Office of Surface Mining Reclamation and Enforcement, Department of the
Interior (30 CFR parts 700-999)
--United States Department of Homeland Security (DHS) Chemical Facility
Anti-Terrorism Standards (CFATS) (6 CFR part 27)

    EPA also analyzed the existing state regulatory framework for CWA
hazardous substance FRPs for all 50 states and found 27 programs with
elements potentially comparable to those required by CWA section
311(j)(5), available in the TBD. EPA found state coverage is an
inconsistent patchwork and cannot be relied upon for uniform,
nationwide CWA hazardous substance FRP requirements.
    Additionally, EPA analyzed existing industry standards related to
CWA hazardous substance FRPs for four standards with elements
potentially comparable to those required by CWA section 311(j)(5).
However, these standards are voluntary and do not provide comprehensive
coverage of proposed CWA hazardous substance FRP program elements.
    Again, the TBD contains a more detailed discussion of each proposed
program element and regulation, program, or standard. EPA solicits
comment on this analysis as well as on other programs or standards EPA
should examine.

IV. Proposed Action

    EPA is proposing a regulatory program whereby those facilities that

could reasonably be expected to cause substantial harm to the
environment, based on their location, are required to prepare and
submit CWA hazardous substance FRPs for worst case discharges to the
EPA. EPA will approve only those CWA hazardous substance FRPs submitted
for facilities that could cause significant and substantial harm to the
environment. EPA proposes that FRPs must be consistent with the NCP and
ACPs; identify the qualified individual having full authority to
implement response actions and require immediate communications between
that individual and the appropriate Federal official and the persons
providing personnel and equipment, with a description of duties;
identify, and ensure by contract or other approved means, the
availability of private personnel and equipment necessary to respond to
the maximum extent practicable to a worst case discharge of CWA
hazardous substances (including a discharge resulting from fire or
explosion), and to mitigate or prevent a substantial threat of such a
discharge; describe the training, equipment testing, periodic
unannounced drills, and response actions of persons at the facility;
and review and update facility response plan periodically and resubmit
to the RA for approval of each significant change. Specific CWA
hazardous substance FRP components will include: facility information,
owner or operator information, hazard evaluation, reportable discharge
history, response personnel and equipment, evidence of contracts or
other approved means to ensure the availability of personnel and
equipment, notification lists, discharge information, personnel roles
and responsibilities, response equipment information, evacuation plans,
discharge detection systems, response actions, disposal plans,
containment measures, training and exercise procedures, self-
inspection, a coordination activities. Please see section IV.B of this
preamble for specific discussion of each of these components.
    To identify potential elements to include in this proposal, EPA
reviewed existing regulations that include emergency response planning
provisions as well as the USCG regulatory proposals to establish
requirements for CWA hazardous substance worst case discharges.
Specifically, EPA considered existing requirements for Oil Pollution
Prevention FRPs under 40 CFR part 112 (or oil FRPs) given that these
requirements have been in place since 1994 and were promulgated under
the same statutory authority as this proposal. Of note, CWA hazardous
substances vary widely in physical and chemical properties when
compared to oils; EPA has closely considered these variations in this
proposal. Additionally, EPA examined requirements under the RMP rule
under 40 CFR part 68, which implements section 112(r)(7) of the Clean
Air Act and requires facilities that use regulated substances to
develop an RMP.

A. Applicability Criteria

    The statute governing CWA hazardous substances worst case
discharges specifies that those facilities that could reasonably be
expected to cause substantial harm to the environment, based on their
location, are required to prepare and submit CWA hazardous substance
FRPs for worst case discharges to the EPA. EPA will approve or
disapprove only those CWA hazardous substance FRPs submitted for
``significant and substantial harm facilities.''
    EPA is proposing in Sec.  118.3 two initial screening criteria to
determine whether a facility, because of its location, could cause
substantial harm to the environment from a worst case discharge into or
onto navigable water. The first step in assessing applicability is to
determine whether a facility has the container capacity for a CWA
hazardous substance onsite at or above a threshold quantity. If so, the
facility owner or operator then determines whether the facility is
within one-half mile to navigable water or a conveyance to navigable
water. EPA solicits comment on alternative or additional screening
criteria with supporting rationale and data. If those two conditions
are satisfied, the owner or operator determines whether the facility
meets any of the four substantial harm criteria: The ability to
adversely impact a public water system; the ability to cause injury to
fish, wildlife, and sensitive environments (FWSE); the ability to cause
injury to public receptors; and/or having had a reportable discharge of
a CWA hazardous substance within the last five years. If any of those
substantial harm criteria are met, then the owner or operator must
submit a CWA hazardous substance FRP to EPA. Additionally, EPA is
proposing in Sec.  118.5(a) that an EPA Regional Administrator has the
authority to require CWA hazardous substance FRPs, after consideration
of site-specific factors for a facility, regardless of whether a
facility meets the criteria in proposed Sec.  118.3. To determine
whether a facility could reasonably be expected to cause substantial
harm following a CWA hazardous substance worst case discharge, EPA is
proposing factors for the RA to evaluate in Sec.  118.5(b). Please see
further discussion of Regional Administrator authorities to require CWA
hazardous substance FRPs and determination of significant and
significant and substantial harm in A.2.f of this section.
    Proposed applicability criteria include:
    Threshold Quantity: To account for the 296 different CWA hazardous
substances with various properties, EPA is proposing to apply a maximum
capacity onsite criterion threshold quantity for each CWA hazardous
substance by using a multiplier of the CWA RQ, based on the RQ
categories specified in 40 CFR part 117.
    Facility location: EPA is proposing to use facility location
relative to navigable waters as an applicability screening criterion
for CWA hazardous substance FRP facilities. Specifically, facilities
meeting or exceeding the CWA hazardous substance maximum capacity
onsite threshold quantity and located within one-half mile of a
navigable water or a conveyance to a navigable water must determine if
the facility meets at least one substantial harm criterion.
    Ability to cause injury to fish, wildlife, and sensitive
environments (FWSE): EPA proposes a substantial harm criterion for
facilities located at a distance such that a CWA hazardous substance
discharge has the potential to cause injury to FWSE. EPA proposes to
codify parameters and toxic endpoints to be used by facility owners
when determining whether a worst case CWA hazardous substance discharge
could cause injury to FWSE.
    Ability to adversely impact a public water system: EPA is proposing
to require facility owners or operators to coordinate with nearby
public water systems to determine whether a CWA hazardous substance
worst case discharge could adversely impact a public water system.
    Ability to cause injury to public receptors: EPA is proposing a
substantial harm criterion for facilities located at a distance such
that a CWA hazardous substance discharge could cause injury to public
receptors. EPA proposes a definition for public receptors as those
areas where the public could be exposed to a CWA hazardous substance
worst case discharge to navigable waters. EPA further proposes that the
same parameter and toxic endpoints used for the FWSE substantial harm
criterion

apply for determining injury to public receptors.
    Reportable discharge history: EPA is proposing a substantial harm
criterion that identifies whether the facility has had a reportable CWA
hazardous substance discharge to water within the last five years. A
reportable discharge is defined in 40 CFR 117.21 as any discharge in
quantities equal to, or exceeding, in any 24-hour period, the
reportable quantity in 40 CFR 117.3, the discharge of which violates
CWA section 311(b)(3).
[GRAPHIC] [TIFF OMITTED] TP28MR22.242

    EPA is proposing a definition of ``facility'' in Sec.  118.2 that
is adopted from the Oil Pollution Prevention regulation at 40 CFR
112.2.\15\ This definition is broad and captures the types of
facilities intended to be regulated by EPA under CWA hazardous
substance worst case discharge regulations. The Agency recognizes that
under this definition, the owner or operator has the discretion to
determine what constitutes a facility. That is, the proposed rule may
become applicable to a facility in cases of aggregation of buildings,
structures, or equipment and associated storage or type of activity, or
the division of the facility may end applicability due to separation of
buildings, structures, or equipment and associated CWA hazardous
substance storage or type of activity. However, an owner or operator
may not make facility determinations indiscriminately and in such a
manner as to simply avoid applicability of the proposed rule (for
example, the division of one facility into separate facilities with one
CWA hazardous substance container located at each facility where all
containers are located side-by-side or in close proximity to each other
and are used for the same purpose). EPA solicits comment on this
definition and any appropriate adjustments with supporting rationale
and data.
---------------------------------------------------------------------------

    \15\ See EPA's ``SPCC Guidance for Regional Inspectors'' https://www.epa.gov/oil-spills-prevention-and-preparedness-regulations/spcc-guidance-regional-inspectors.
---------------------------------------------------------------------------

1. Screening Criteria
a. CWA Hazardous Substance Capacity Threshold Quantity
i. 10,000x CWA Hazardous Substance RQ Multiplier
    In Sec.  118.3, EPA is proposing that if the maximum capacity
onsite, as defined in Sec.  118.2 (the total aggregate container
capacity for each CWA hazardous substance present at all locations
within the entire facility at any one time) at the facility of any CWA
hazardous substance, at any one time, meets or exceeds 10,000 times its
RQ, the facility has met the threshold quantity. If a facility's
container capacity meets or exceeds the threshold quantity for any one
CWA hazardous substance and the facility is within one-half mile of
navigable waters, then the facility owner or operator must determine if
the facility meets at least one substantial harm criterion proposed in
this action. If so, the entire facility would be subject to the CWA
hazardous substance FRP requirements proposed in this action for all
CWA hazardous substances stored or used at the facility.
    EPA chose to use a multiplier of the CWA hazardous substance RQ as
the threshold quantity because RQs represent a quantity that may be
harmful when discharged to navigable waters. For a facility to cause
substantial harm to the environment, it would need to reasonably be
expected to cause a discharge in a quantity larger than the RQ and
would therefore need to have the capacity to store significantly larger
quantities onsite.
    RQs exist for all CWA hazardous substances and reflect relative (in
relation to other CWA hazardous substances, due to the five categories
detailed below, see Table 5) and aquatic

toxicity.\16\ In accordance with 40 CFR 117.21, CWA hazardous substance
discharges to navigable waters or adjoining shorelines require
notification to the NRC when the CWA hazardous substance discharge is
equal to, or exceeds, in any 24-hour period, the RQ in 40 CFR 117.3.
---------------------------------------------------------------------------

    \16\ These values were later adopted by Comprehensive
Environmental Response, Compensation, and Liability Act of 1980
(CERCLA).
---------------------------------------------------------------------------

    The RQs were originally developed in 1979 and adjusted beginning
with an evaluation of the intrinsic physical, chemical, and
toxicological properties of each CWA hazardous substance. The intrinsic
properties examined, also called the ``primary criteria,'' were aquatic
toxicity, mammalian toxicity (oral, dermal, and inhalation),
ignitability, reactivity, chronic toxicity, and potential
carcinogenicity.\17\ Generally, for each intrinsic property, EPA ranked
CWA hazardous substances on a scale, associating a specific range of
values on each scale with an RQ value of 1, 10, 100, 1,000, or 5,000
lbs. EPA evaluated the data for each CWA hazardous substance using
various primary criteria; each CWA hazardous substance may have
received several tentative RQ values based on its particular intrinsic
properties. The lowest of the tentative RQs became the ``primary
criteria RQ'' for that substance, which EPA used to assign an initial
category of X, A, B, C, or D. After EPA assigned the primary criteria
RQ, EPA further evaluated substances for their susceptibility to
certain degradative processes, which were used as secondary adjustment
criteria. These natural degradative processes were biodegradation,
hydrolysis, and photolysis (BHP). If a CWA hazardous substance, when
discharged into the environment, degrades relatively rapidly to a less
hazardous form by one or more of the BHP processes, its RQ (as
determined by the primary RQ adjustment criteria), was generally
adjusted down one level (e.g., from Category A to Category B).
Conversely, if a CWA hazardous substance degrades to a more hazardous
product after its discharge, the original substance was assigned an RQ
equal to the RQ for the more hazardous substance, which may have been
one or more levels higher than the RQ for the original substance (e.g.,
from Category C to Category A). This approach in developing RQs may not
reflect the ignitability or reactivity of single substances or among
multiple substances that may comingle, or the potential for the
additive or synergistic effects in the toxicity of two or more CWA
hazardous substances.
---------------------------------------------------------------------------

    \17\ In 1979, EPA established RQs at 40 CFR 117 (44 FR 50766,
August 29, 1979), which used the acute aquatic toxicity of the CWA
hazardous substances to determine RQs. For a detailed discussion of
this methodology, see 43 FR 10489-92 (March 13, 1978) and 40 FR
59982-89 (December 30, 1975). In 1985, EPA amended 40 CFR part 117
to make reportable quantities adjusted under CERCLA the applicable
reportable quantities for hazardous substances pursuant to CWA
section 311 (50 FR 13456, April 4, 1985). In this action, EPA
established a methodology for adjusting RQs, which established
``primary criteria'' as aquatic toxicity, mammalian toxicity (oral,
dermal, and inhalation), ignitability, reactivity, and chronic
toxicity. EPA subsequently established a methodology for including
potential carcinogenicity as a ``primary criterion'' (see, for
example, 54 FR 33418, August 14, 1989 and 54 FR 33426, August 14,
1989).

  Table 5--CWA Hazardous Substance Categories and Reportable Quantities
------------------------------------------------------------------------
                                                     Reportable quantity
                      Category                              (lbs)
------------------------------------------------------------------------
X..................................................                    1
A..................................................                   10
B..................................................                  100
C..................................................                1,000
D..................................................                5,000
------------------------------------------------------------------------

    Using the RQ as a basis to characterize a facility that has the
ability to cause substantial harm in the event of a worst case
discharge has the advantage of building a regulatory structure using
existing quantifiable values that have previously been vetted through
the rulemaking process. The public, industry, and EPA are familiar with
these concepts. Additionally, RQs reflect varying levels of and
relative risk, based on the methodology outlined above, so
applicability criteria under the proposed rule are scaled to the
specific circumstances of each facility, rather than applying a one-
size-fits-all approach. However, the properties of listed CWA hazardous
substances may not be fully captured in the RQs because the existing
RQs may not be based on the most current risk data.
    This rulemaking is explicitly focused on response planning for
worst case CWA hazardous substances discharges to navigable waters. EPA
recognizes that multiple factors contribute to the likelihood of a CWA
hazardous substance worst case discharge to navigable waters, including
but not limited to, physical and chemical properties of the CWA
hazardous substance, quantity stored onsite, size of storage
containers, cause of the discharge, proximity to navigable waters or
conveyances, properties of the terrain, drainage pathways, weather,
etc. EPA expects that excessively low threshold quantities would likely
be overly cautious and regulate facilities that are not likely to cause
substantial harm to the environment. Establishing a lower threshold
planning quantity for all CWA hazardous substances could potentially
overwhelm local and facility emergency planning efforts and would not
be commensurate with the danger posed by individual substances.
    The 10,000x RQ multiplier assumes that larger capacities of CWA
hazardous substances generally correspond to an increased risk of
adverse impacts to receptors should a worst case discharge occur. As
discussed in Section III of this preamble, the RQs are quantities that
``may be harmful,'' thus, by definition, they do not represent a worst
case discharge quantity. Additionally, as discussed in Section
IV(A)(2)(d) of this preamble, the definition of ``size classes of
releases'' in 40 CFR 300.5, which corresponds with hazardous substance
releases under the NCP, is not tied to a particular quantity; rather, a
major release is a ``release of any quantity of hazardous substance(s),
pollutant(s), or contaminants(s) that poses a substantial threat to
public health or welfare of the United States or the environment or
results in significant public concern.'' Under the NCP, the On-Scene
Coordinator (OSC) makes the final determination of the appropriate
classification of a hazardous substance release based on consideration
of the particular release (e.g., size, location, impact, etc.). EPA
concludes that to focus on the threat of these major releases, in terms
of applicability, adjusting the RQ upward is warranted.
    EPA recognizes that the multiplier proposed here does not represent
a ``safe'' quantity in the event of a CWA hazardous substance
discharge. However, EPA determined the 10,000x RQ multiplier reflects
the range of risks posed by the listed CWA hazardous substances,
whether they are used at large or small facilities, by preserving the
underlying toxicity parameters used to establish the original RQs. EPA
notes, however, owners and operators are responsible for remaining
cognizant of the maximum capacity(ies) onsite of all CWA hazardous
substances at any one time and determining whether the maximum capacity
onsite is at or exceeds 10,000x the RQ found at 40 CFR 117.3.
    The proposed rule requires detailed planning requirements for
responding to worst case discharges. These requirements should be
triggered only when maximum capacities onsite of CWA hazardous
substances are large enough to pose a risk of substantial harm to
public health or the environment. While EPA recognizes that site-
specific factors, such as site elevations and location and nature of

the discharge point, could affect the likelihood or effects of a
discharge, EPA does not believe it is feasible to develop a methodology
for establishing threshold quantities based on site-specific factors
that would be applicable uniformly nationwide for every CWA hazardous
substance. This is consistent with EPA's original approach in setting
the RQs and reflected in the regulatory history and language.\18\ EPA
examined other threshold multipliers, available in the RIA, including
10x, 100x, and 1,000x multipliers; however, these multipliers would not
focus the proposed emergency planning requirements on those facilities
with the greatest potential to cause substantial harm to human health
or the environment. EPA solicits comment on using a 10,000x multiplier
of the RQs for the screening criteria with supporting rationale and
data. EPA also solicits comment on the use of alternative RQ multiplier
values, as well as different multipliers for each category of CWA
hazardous substance, in addition to any supporting data or studies on
this topic.
---------------------------------------------------------------------------

    \18\ See Footnote 17.
---------------------------------------------------------------------------

I. Alternative Applicability Approaches
Establish New Regulatory Thresholds Based on Toxic Endpoints
    EPA also considered developing applicability thresholds using
representative receptors for each of the three categories of receptors
considered under this proposed rule (FWSE, public receptors, and public
water systems) in order meet the specific objectives of this rule.
    Under this approach, EPA would set new threshold quantities for
each CWA hazardous substance using the most current risk data. Each CWA
hazardous substance would be evaluated to determine (1) how a discharge
could cause substantial harm to each type of receptor, and (2) the
concentration at which substantial harm would be likely to occur for
each type of receptor. The lowest concentration that could cause
substantial harm to any receptor would serve as the basis for
establishing a single applicability threshold for each CWA hazardous
substance. A standard conservative dilution factor would be used to
relate the substantial harm concentration to a quantity of the CWA
hazardous substance onsite at a facility that would then serve as the
applicability threshold for that CWA hazardous substance.
    While this approach could effectively target facilities based on
their effects on the receptors of interest, there are significant
drawbacks to this strategy. Development of new CWA hazardous substance-
specific worst case discharge thresholds would unduly delay
implementation of this protective regulation, and there would be data
gaps. Additionally, simplifying assumptions would be necessary to
develop a dilution factor used to convert a concentration at a
downstream receptor to a mass stored at a facility. EPA solicits
comment on establishing new regulatory thresholds for CWA hazardous
substance FRP applicability using the most current risk data and
appropriate endpoints, including the methodology, data, and rationale;
appropriate dilution factors; and feasibility of implementation.
Establish Thresholds Using Distance-Based Multipliers
    EPA considered establishing applicability thresholds using
distance-based multipliers for CWA hazardous substance RQs. This
approach recognizes that the potential for a CWA hazardous substance
worst case discharge from a facility to cause substantial harm to a
downstream receptor (i.e., public water system, FWSE, or public
receptor) depends on the distance and travel time from the facility to
a downstream receptor over land and water, among other factors (e.g.,
river width, gage height, flow velocity, land transport considerations,
lateral dispersion and/or diffusion). As distance increases, the
contaminant concentration at the receptor decreases, while the time
available to respond to the discharge increases; thus, the further a
facility is from a receptor, the lower the potential for substantial
harm, all other factors being equal. By applying a multiplier to the RQ
based on the distance from the facility to the nearest downstream
receptor, the regulation could better target facilities that are more
likely to cause substantial harm in the event of a worst case
discharge.
    Under this approach, an owner or operator would be required to
calculate a planning distance to the nearest downstream receptor if the
following two conditions are met: The facility has more than 10x the RQ
of the CWA hazardous substance onsite and the facility is within one-
half mile of navigable water or a conveyance leading to navigable
water. The planning distance to the nearest downstream receptor is then
used to establish the distance-based applicability threshold using the
simple equation: RQ x distance x 100, where distance is the planning
distance, in miles, between the facility and the nearest downstream
receptor. The planning distance includes travel overland and in water.
For a release of the same amount, the concentration at a receptor is
inversely proportional to the distance from the point of release to the
receptor. Thus, inclusion of a ``distance factor'' in the equation to
establish an applicability threshold will appropriately establish a
lower threshold for facilities that are closer to downstream receptors,
and thus present a greater risk.
    Facilities with onsite quantities greater than this distance-based
threshold would then be required to conduct an analysis to determine
whether the facility has the potential to cause substantial harm in the
event of a worst case discharge. Only if the analysis determines that
the facility has the potential to cause substantial harm in the event
of a worst case discharge would the facility be required to develop a
CWA hazardous substance FRP.
    EPA recognizes that use of planning distance in the applicability
determination may better target facilities with the potential to cause
substantial harm without unnecessarily increasing the size of the
regulated universe, because facilities located further upstream from a
receptor would have a proportionately higher applicability threshold.
This approach would be more complicated for the regulated community to
implement, relative to the use of a single threshold multiplier (e.g.,
10,000), and for EPA to evaluate and enforce. EPA solicits comment on
this approach, as well as any supporting data, information pertaining
to additional costs, considerations for appropriate multipliers to use,
and underlying methodology, data, and rationale.
Thresholds From Other Hazardous Substances Regulations (Non-CWA)
    EPA reviewed other hazardous substance regulations for potential
consideration of applicability thresholds, including:

--Chemical Accident Prevention Provisions, RMP List of Substances (40
CFR 68.130)
--EPCRA Section 302: Threshold Planning Quantities for Emergency
Planning (40 CFR part 355, Appendices A and B)
--EPCRA Section 304: Reportable Quantities for Emergency Release
Notification (40 CFR part 355, Appendices A and B)
--EPCRA Sections 311 and 312: Reporting Thresholds for Hazardous
Chemical Reporting: Community Right to Know (40 CFR 370.10)
--EPCRA Section 313: Toxic Chemical Release Reporting (40 CFR 372.65)

    These are detailed in the TBD. EPA concluded that the methodologies
used to create the reporting thresholds under these regulations are not
appropriate for CWA hazardous substance response planning.
Additionally, EPA found that only EPCRA Sections 311 and 312 include
all substances on the 40 CFR part 116 list of CWA hazardous substances.
However, the applicability for EPCRA sections 311 and 312 regulations
is if any OSHA hazardous chemical is present at the facility at or
above the reporting thresholds at any one time. EPA solicits comment on
any other chemical threshold approaches from Federal or state
regulations, industry standards, etc. that EPA should consider,
including data and rationale.
II. Alternative Thresholds by Aggregated Category
    EPA considered options involving aggregating chemical capacity by
RQ category or by removability or recoverability in the event of a
discharge. To aggregate by RQ category to determine whether a facility
meets the threshold quantity for the maximum capacity onsite proposed
in Sec.  118.3(a), a facility could be required to add up the
capacities of CWA hazardous substance containers present onsite by
category. If, in aggregate, the capacity of those containers in each
category reaches the threshold quantity, the owner or operator would be
required to determine whether the facility is within one-half mile of
navigable water and then whether the facility meets any of the
substantial harm criteria.
    EPA decided this approach is inappropriate due to the wide
variability of physicochemical properties for CWA hazardous substances
within each category. Additionally, under this approach, facilities
with small amounts of multiple chemicals in each category may be
required to do facility response planning for improbable events
impacting multiple small containers, or other containers where the
likelihood of concurrent catastrophic discharge is very low. Finally,
this approach would require EPA to select a capacity threshold for each
category above which facilities would be regulated. EPA found no basis
for selecting a threshold for aggregate capacity for each category.
    EPA solicits comment on the approach to aggregate CWA hazardous
substances within categories to determine whether a facility has
reached the threshold quantity for applicability, as well as
alternative approaches to aggregating quantities of different CWA
hazardous substances with supporting rationale and data.
    In terms of categorizing CWA hazardous substances by removability
and recoverability for response resource planning, EPA previously
proposed and revoked rules that could guide that discussion. On March
13, 1978, EPA issued 40 CFR part 117 to determine the removability of
each CWA hazardous substance and 40 CFR part 119, which determined
units of measurement and penalties (43 FR 10488 and 43 FR 10495). On
November 2, 1978, section 311 of the CWA was amended by Public Law 95-
576. The amended statute no longer required the Agency to make
determinations of removability or units of measurement for computing
penalties. Therefore, 40 CFR parts 117 and 119 of the March 13, 1978
regulations were revoked on February 16, 1979 (44 FR 10269). The basis
for determining reportable quantities, formerly termed ``harmful
quantities,'' was simplified by the amendment and, thus, part 118 of
the March 13, 1978 regulations was also revoked and reportable
quantities were reproposed as a new part 117 on February 16, 1979 (44
FR 10271) as ``quantities that may be harmful.''
    In 40 CFR part 117: Determination of Removability of Hazardous
Substances (43 FR 10488) (since revoked), EPA discussed designating
certain substances as those that can actually be removed under most
conditions of discharge. These substances have limited water
solubility, a relatively cohesive mass, and are less dense than water.
Thus, they resemble petroleum oils in their behavior when discharged to
water. The substances can be described as those with specific gravities
less than 1.0 and water solubility less than 1,000 mg/l. Accordingly,
the revoked final rule made the determination that allyl acetate,
ethylbenzene, xylene, allyl chloride, benzene, cyclohexane, isoprene,
methyl methacrylate, styrene, and toluene could actually be removed and
identified them as oil-like CWA hazardous substances.
    Additionally, under 40 CFR part 119: Units of Measurement & Rates
of Penalty (43 FR 10495) (now revoked), EPA discussed applying an
adjustment factor to penalties (0.1 to 1.0) using a profiling operation
based on the solubility, density, volatility, and associated propensity
for dispersal in water of each CWA hazardous substance. Each CWA
hazardous substance was placed in one of eight categories combining
these physical, chemical, and dispersal properties in various ways. EPA
then ranked the relative harm these categories posed to the
environment. Table 6 shows the terms involved; final relative ranking
of physical, chemical, and dispersal categories in increasing order of
relative damage potential; and physical, chemical, and dispersal factor
of each category.

                               Table 6--Material Classification and Relative Harm
----------------------------------------------------------------------------------------------------------------
                                                                                Physical/
           Material classification               Physical/ chemical/ dispersal         Rank          chemical/
                                                            category                                 dispersal
----------------------------------------------------------------------------------------------------------------
Insoluble Volatile Floater...................  IVF..............................               1            0.10
Insoluble Nonvolatile Floater................  INF..............................               2            0.23
Insoluble Sinker.............................  IS...............................               3            0.36
Soluble Mixer................................  SM...............................               4            0.49
Precipitator.................................  P................................               5            0.62
Soluble Sinker...............................  SS...............................               6            0.75
Soluble Floater..............................  SF...............................               7            0.88
Miscible.....................................  M................................               8             1.0
----------------------------------------------------------------------------------------------------------------

    The eight categories were defined as:
    1. IVF (insoluble volatile floater): Materials lighter than water
with a vapor pressure greater than 10 mm Hg and a solubility of less
than 1,000 ppm (weight per weight basis) or materials with vapor
pressure greater than 100 mm Hg and solubility less than 10,000 ppm.

    2. INF (insoluble nonvolatile floater): Materials lighter than
water with a vapor pressure greater than 10 mm Hg and a solubility of
less than 1,000 ppm (weight per weight basis).
    3. IS (insoluble sinker): Materials heavier than water and with a
solubility less than 1,000 ppm (weight per weight basis).
    4. SM (soluble mixer): Solid substances with a solubility greater
than 1,000 grams of solute per 1,000 grams of water.
    5. P (precipitator): Salts which dissociate or hydrolyze in water
with subsequent precipitation of a toxic ion.
    6. SS (soluble sinker): Materials heavier than water and a
solubility greater than 1,000 ppm (weight per weight basis).
    7. SF (soluble floater): Materials lighter than water and a
solubility greater than 1,000 ppm (weight per weight basis).
    8. M (miscible): Liquid substances which can freely mix with water
in any proportion.
    EPA considered, but decided against, using these revoked categories
for a listed hazardous substance's ability to be removed under most
conditions of discharge to aggregate hazardous substances for
establishing an applicability threshold quantity. EPA judged that
aggregating in this fashion is impractical; may not adequately reflect
risks, including inherent, CWA hazardous substance-specific toxic,
explosive, ignitable and/or reactive natures, especially during an
extreme event; and implementation and compliance would be complicated.
Additionally, as these regulations were revoked, industry is unfamiliar
with this approach and facility planners do not use these categories in
their planning. EPA solicits comment on aggregating CWA hazardous
substances, as detailed above, with supporting rationale and data.
    Additionally, in the USCG proposed rules for tank vessels and MTR
facilities (64 FR 13734, March 22, 1999 and 65 FR 17416, March 31,
2000), some CWA hazardous substances were defined as ``sinkers'' and
``floaters'', where ``sinkers'' are those CWA hazardous substances
whose physical and chemical properties, following a discharge into
water, result in a substance in the water that does not float, react
chemically with water, rapidly vaporize, or rapidly dissolve. Under
ambient conditions, these chemicals have a solubility of less than 0.01
percent, specific gravity greater than 1.0, and a vapor pressure less
than 1 PSIG. ``Floaters'' are those CWA hazardous substances whose
physical and chemical properties, following a discharge into water,
result in a substance on the water surface that does not rapidly sink,
react chemically with water, vaporize, or dissolve. Under ambient
conditions, these CWA hazardous substances have a solubility of less
than 0.01 percent, a specific gravity less than 1.0, and a vapor
pressure less than 1 PSIG. Neither a ``sinker'' or ``floater''
designation was intended to include CWA hazardous substances that are
highly reactive in water or volatile, and therefore could not be
reasonably contained or collected under any conditions.
    Categorizing chemicals in this fashion is more intuitive than the
EPA-revoked eight categories in Table 6 above. Additionally, ``sinker''
and ``floater'' would specifically link to response requirements, the
main focus of this action. However, again due to the wide variability
in chemical properties and requirements around responding to a worst
case discharge, EPA determined that categorizing and aggregating
chemicals generally is not appropriate for this action for the reasons
specified above for aggregating by the revoked categories.
    EPA solicits comment on using ``sinkers'' and ``floaters'' as
chemical categories to require specific response planning resources be
available or contracted, or in aggregating chemicals for threshold
determinations with supporting rationale and data.
ii. Maximum Capacity Onsite v. Maximum Quantity Onsite
    EPA is proposing in Sec.  118.2 to define maximum capacity onsite
as the total aggregate container capacity of each CWA hazardous
substance present at all locations within the entire facility at any
given time, similar to the approach taken in the Oil Pollution
Prevention regulation (see 40 CFR part 112). EPA is proposing a
definition for permanently closed containers in Sec.  118.2 such that
facilities would not need to count these containers in their CWA
hazardous substance maximum capacity onsite threshold quantity
calculations.
    EPA recognizes that for the chemical industry, chemical inventory
quantities routinely fluctuate, and facilities use a wide variety of
containers to store CWA hazardous substances; common containers include
storage tanks, process vessels, railcars, and other onsite shipping
containers not in transportation. Thus, regulating facilities based on
the maximum container capacity onsite will allow regulated stakeholders
an opportunity to plan for the worst case quantities of CWA hazardous
substances at the facility. This approach also allows emergency
response planners to reflect the risk posed by CWA hazardous substances
onsite in those maximum possible quantities. This is a simpler approach
for inspectors to determine facility applicability based on container
sizes instead of reviewing and aligning quantities in fluctuating
inventories. Furthermore, calculating applicability using container
shell capacity could be viewed as a more conservative approach to
determine whether a facility has reached the threshold quantity of CWA
hazardous substances.
    There are some limitations to this approach. Chemical mixtures
would be complex to regulate, and the approach does not allow for
flexibility. Oils are fundamentally different from CWA hazardous
substances in that when an oil is mixed with another substance, the
entire mixture is subject to regulation under CWA section 311 and the
Oil Pollution Prevention regulation. Therefore, when determining
applicability for oils, the shell capacity of the container can be
taken into account because the entire mixture in the container is
considered an oil for regulatory purposes. However, CWA hazardous
substances may be combined into mixtures and therefore it is necessary
to understand the quantities of each substance in the mixture to
determine total quantities onsite when determining applicability.
Furthermore, EPA understands that CWA hazardous substance facility
quantities and batch process operations often vary and therefore EPA
inspectors would still need to consider facility inventories to
understand facility storage capacities. Additionally, this approach is
not consistent with how industry manages their chemicals under similar
chemical preparedness and reporting regulations. The typical amount of
CWA hazardous substances at a facility may be less than the total
capacity because facilities are overdesigned to meet seasonal demands
or changing facility need. Finally, containers may be designed to never
actually hold the maximum quantity possible due to the need for
freeboard or headspace, thus using the maximum capacity onsite may not
be a realistic accounting of CWA hazardous substance quantities for
planning purposes.
    EPA considered proposing that the maximum quantity stored onsite
means the total amount of a CWA hazardous substance present at all
locations within the entire facility at any given time (e.g., storage
tanks, process vessels, onsite shipping containers) and that this
amount be used to determine whether a facility meets or exceeds the
threshold

quantity proposed in Sec.  118.3(a). This is consistent with other EPA
chemical accident preparedness and reporting programs, for example
EPCRA Sections 311 and 312.\19\ A facility owner or operator would use
the maximum total aggregate amount of a CWA hazardous substance in all
containers onsite at any one time to calculate this quantity. Once a
facility becomes subject to the regulation for one CWA hazardous
substance, the facility would include all CWA hazardous substances on
site in their planning activities.
---------------------------------------------------------------------------

    \19\ See 40 CFR part 370.
---------------------------------------------------------------------------

    EPA solicits comment on the proposed approach, the definition of
permanently closed containers, using maximum quantity onsite rather
than maximum capacity onsite for applicability threshold quantity
calculations, the number of facilities that may be regulated under the
proposed approach versus using maximum quantity onsite, and potential
alternative approaches with supporting rationale and data.
iii. Accounting for Mixtures
    When designating CWA hazardous substances, EPA defined mixture in
40 CFR 116.3 to mean any combination of two or more elements and/or
compounds in solid, liquid, or gaseous form except where such
substances have undergone a chemical reaction so as to become
inseparable by physical means. Additionally, 40 CFR 116.4 states that
the elements and compounds appearing in Tables 116.4 A and B are
designated as hazardous substances in accordance with CWA section
311(b)(2)(A). This designation includes any isomers and hydrates, as
well as any solutions and mixtures containing these substances.
    Under 40 CFR 302.6 Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA) Notification Requirements,
hazardous substance mixtures are calculated by the following: (i) If
the quantity of all of the hazardous constituent(s) of the mixture or
solution is known, notification is required where an RQ or more of any
hazardous constituent is discharged; (ii) If the quantity of one or
more of the hazardous constituent(s) of the mixture or solution is
unknown, notification is required where the total amount of the mixture
or solution discharged equals or exceeds the RQ for the hazardous
constituent with the lowest RQ.
    As the regulated community is already familiar with determining RQs
for mixtures or solutions for release notification under CERCLA section
103(a) (40 CFR 302.6), EPA is proposing the same requirements in Sec.
118.9 for mixtures or solutions in this action. As such, if a facility
has a mixture wherein the quantities of all the hazardous constituents
of the mixture are known, the threshold quantity would be reached when
any individual CWA hazardous substance constituent quantity reaches
that level as extrapolated to the maximum container capacity. However,
if a facility has a mixture wherein the quantities of the constituents
are not known, the facility has met the threshold when the entire
quantity of the mixture onsite reaches or exceeds the threshold
quantity for the hazardous constituent with the lowest threshold when
extrapolated to the maximum container capacity. EPA solicits comment on
this approach or suggested alternative approaches with supporting data
for determining CWA hazardous substance threshold quantities for
mixtures.
    Because this proposed action would determine threshold quantity
applicability based on maximum capacity onsite, a facility would follow
the mixture rule proposed in Sec.  118.9 to determine the capacity
quantities of CWA hazardous substances onsite. For the worst case
discharge planning quantity, please see Section IV.A.4.iv of this
preamble.
b. Distance to Navigable Water
i. One-Half Mile to Navigable Water or Conveyance to Navigable Water
    EPA is proposing that facilities meeting the threshold quantity of
CWA hazardous substances and located within one-half mile of navigable
water or a conveyance to navigable water complete the substantial harm
determination. This distance is based on research related to the Oil
Pollution Prevention FRP regulation.\20\ As discussed in the preamble
to the Oil Pollution Prevention FRP regulation,\21\ all facilities with
worst case discharges of oil to navigable water examined in the case
studies were located such that their closest opportunity for discharge
was within one-half mile of navigable waters. Thus, 40 CFR part 112,
Appendix C, Attachment C-III--Calculation of the Planning Distance
considers one-half mile proximity to a navigable water or a conveyance
to navigable water as part of the planning distance calculation for
overland transport. These overland transport planning distance
calculations, combined with in-water calculations, determine whether
the facility could cause substantial harm to public health and
sensitive environments due to a worst case discharge. Additionally,
conveyances located close to the facility can provide a direct pathway
to navigable waters. If this distance is less than or equal to one-half
mile, a discharge from the facility could pose substantial harm given
that the time to travel the distance from the storm drain or other
conveyance to the navigable water could be considered virtually
instantaneous (40 CFR 112, Appendix C). Given that the Oil Pollution
Prevention FRP regulation has been in place for over 30 years, industry
is familiar with this approach.
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    \20\ 58 FR 8832, February 17, 1993.
    \21\ ibid.
---------------------------------------------------------------------------

    EPA considered using both lower and higher values for the distance
to navigable water or conveyances to navigable water and solicits
comment on alternative approaches to determining whether a facility,
because of its location, could reasonably be expected to cause
substantial harm to the environment by discharging CWA hazardous
substances into or on the navigable waters, with supporting rationale
and data.
ii. Alternatives to One-Half Mile to Navigable Water or Conveyance to
Navigable Water
    EPA considered a facility self-determination model, wherein an
owner or operator would determine whether the facility has a reasonable
expectation to cause substantial harm by discharging to navigable
waters based on locational and geographic considerations using EPA-
defined criteria. Under this model, the determination would be
customized by each facility to their unique circumstances. The main
drawback to this approach is that defining universally applicable
criteria to determine whether facilities are located at a distance that
may cause substantial harm may be complicated and implementation may be
difficult and burdensome.
    EPA also considered establishing proximity distances to navigable
waters for CWA hazardous substances using chemical characteristics or
historical discharge data. Under this approach, EPA would use available
CWA hazardous substance physicochemical data to calculate overland
distances to navigable water to indicate that a facility's location
potentially poses a substantial threat. However, the Agency concluded
that determining the appropriate physicochemical properties influencing
fate and transport for the 296 CWA hazardous substances is not feasible
when accounting for the large number of mixtures or wastes containing
CWA hazardous substances.

Additionally, worst case discharge historical data are sparse, and EPA
has identified an insufficient number of historical worst case
discharges of CWA hazardous substances to accurately set a distance
threshold using discharge history data.
    EPA solicits comment and any information pertinent to these
alternative approaches as well as supporting data and rationale.
2. Substantial Harm Criteria
    After determining whether a facility satisfies the initial
screening criteria, EPA is proposing that an owner or operator would
then assess whether their facility meets any of the four substantial
harm criteria: (1) Ability to cause injury to FWSE, (2) ability to
adversely impact a public water system, (3) ability to cause injury to
public receptors, and (4) reportable discharge history. If any one of
these substantial harm criteria are met, then the facility must prepare
and submit a response plan to EPA.
    EPA considered the substantial harm criteria in the Oil Pollution
Prevention regulation in 40 CFR part 112 as a basis for developing CWA
hazardous substances substantial harm criteria. These criteria and
steps to determine whether they are met are further detailed below.
a. Ability to Cause Injury to Fish, Wildlife, and Sensitive
Environments (FWSE)
i. Proposed Approach
    EPA is proposing a substantial harm criterion to consider the
facility's ability to cause injury to FWSE. This is based on 40 CFR
112.20(f)(1)(ii)(B) for oil FRPs, in which EPA established a criterion
for determining injury to FWSE as follows: ``The facility is located at
a distance . . . such that a discharge from the facility could cause
injury to fish and wildlife and sensitive environments . . .''
Furthermore, in 40 CFR 112.20(f)(2)(i) EPA identified that an EPA
Regional Administrator (RA) shall consider proximity to FWSEs and other
areas he or she determines to possess ecological value in his or her
assessment of whether a facility could reasonably be expected to cause
substantial harm to the environment.
    EPA judged that a similar approach considering ability to cause
injury to FWSE is appropriate to determine the potential for CWA
hazardous substance discharges to cause substantial harm to the
environment.
I. Definition of FWSE
    40 CFR part 112 Appendix C references the DOC/NOAA document,
``Guidance for Facility and Vessel Response Plans Fish and Wildlife and
Sensitive Environments,'' which outlines guidance for interpreting
fish, wildlife, and sensitive environments (59 FR 14713, March 29,
1994). In six appendices (I-VI), the guidance document outlines the
Federal agencies responsible for specific environmental resources (I);
critical habitats for endangered/threatened species (II); federally
protected areas (III); sensitive biological and human-use resources
(IV); ranking of shoreline habitats impacted by oil spills (V); and
contact information for regional offices (VI). As part of the statutory
requirements under the CWA, any hazardous substances worst case
discharge program must ``be consistent with the requirements of the
National Contingency Plan (NCP) and Area Contingency Plans (ACPs).''
\22\ EPA is proposing to require owners and operators to evaluate the
substantial harm criteria using the fish and wildlife definition under
40 CFR 112.2 (proposed in this rulemaking in Sec.  118.2) as well as
use applicable ACP guidance in defining fish, wildlife, and sensitive
environments in their respective regions.
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    \22\ 33 U.S.C. 1321(j)(5)(D)(i). Accessed January 14, 2021.
Available at: https://www.govinfo.gov/content/pkg/USCODE-2019-title33/pdf/USCODE-2019-title33-chap26-subchapIII-sec1321.pdf.
---------------------------------------------------------------------------

    An ACP is used by all agencies engaged in responding to
environmental emergencies within a defined geographical area. When
implemented in conjunction with the NCP, the ACP must be adequate to
remove a worst-case discharge, and to mitigate or prevent a substantial
threat of such discharge from a vessel, offshore facility, or onshore
facility operating in or near the defined geographical area.
Additionally, the ACP identifies areas within its bounds that may
require tailored protection or response strategies due to unique
environmental attributes. These may be endangered species habitats or
other areas defined by the ACP. The ACP provides guidance on how
responders should incorporate the needs of these areas into response
strategies. The ACP Fish and Wildlife and Sensitive Environments Plan
annex is developed in consultation with the U.S. Fish and Wildlife
Service, NOAA, and other interested parties, including state fish and
wildlife conservation officials. The annex, consistent with the NCP and
Regional Contingency Plans (RCPs), addresses fish and wildlife
resources and their habitat, and other areas considered sensitive
environments, and provides the necessary information and procedures to
immediately and effectively respond to discharges that may adversely
affect these resources, including provisions for a response to a worst
case discharge (40 CFR 300.210(c)(4)). EPA solicits comment on how
FWSEs are defined for this action.
II. FWSE Planning Distance Calculation
    To determine whether a facility could cause substantial harm to a
FWSE, EPA is proposing that facilities self-determine formulas and/or
methodologies to use for overland transport and transport in water for
planning distance, using EPA-provided parameters and the lethal
concentration 50 percent (LC50) toxicity intervals provided by EPA
(Table 7). The facility owner or operator would be required to evaluate
whether the facility is located at a distance such that a worst case
discharge from the facility could cause injury to FWSE. EPA is
proposing in Sec.  118.10 that a facility owner or operator calculate
the worst case discharge scenario of the maximum single CWA hazardous
substance container, interconnected containers, pipe, or piping system
capacity onsite for a CWA hazardous substance at or above the threshold
quantity set in Sec.  118.3(a) that represents the largest capacity. If
the worst case discharge scenario indicates that the facility could
cause injury to FWSE, then the owner or operator must prepare an FRP
that addresses all CWA hazardous substances where the maximum capacity
onsite meets or exceeds the threshold quantity. The goal of calculating
planning distance is two-fold. First, planning distance determines a
facility's potential to cause substantial harm, and second, planning
distance may be part of the response plan implementation to identify
appropriate response actions. Thus, the worst case discharge scenario
is used to both determine applicability and in the hazard evaluation.
    EPA is proposing to provide the toxicity thresholds and parameters
for overland transport and in-water transport, while the facility must
determine (1) where the FWSE receptors are located, and (2) if, based
on the parameters provided, a worst case discharge of CWA hazardous
substances would result in exposure of receptors to a concentration
equal to or greater than the toxicity threshold concentration provided
by EPA. The following describes the parameters reviewed, the proposed
methodology, and toxic endpoints and parameters for planning distance
calculations.

Toxic Endpoints

    EPA is proposing in Appendix B of 40 CFR part 118 to use 10 percent
of a range of LC50 concentrations. A common risk assessment method, use
of an uncertainty factor of 10 to estimate the lower limit by dividing
the LC50 threshold by 10 (LC50/10) extrapolates the lethal
concentration used in laboratory aquatic toxicity tests to lower
concentrations than the lethal dose. This method results in a
concentration of concern that is more conservative and likely more
relevant to discharges of CWA hazardous substances to the environment.
EPA used tests involving adult fathead minnows to create the original
RQ classification; they are available for all 296 CWA hazardous
substances (43 FR 10474, March 13, 1978). EPA proposes to use 96-hour
LC50 intervals for each RQ category as the criterion for FWSE (Table
7). For mixtures of CWA hazardous substances, EPA proposes in Sec.
118.10(a) that an owner or operator shall assume the entire capacity of
the container holds the CWA hazardous substance with the lowest RQ. EPA
judges that this approach will appropriately capture the risk of CWA
hazardous substance worst case discharges causing injury to FWSE.

                                    Table 7--Proposed Concentrations for FWSE
                                         [Proposed Part 118 Appendix B]
----------------------------------------------------------------------------------------------------------------
                                                                     Aquatic toxicity  (mg/L)
                    Category                        RQ  (lbs.)   --------------------------------   10%  (mg/L)
                                                                       Lower           Upper
----------------------------------------------------------------------------------------------------------------
X...............................................               1               0             0.1            0.01
A...............................................              10             0.1               1             0.1
B...............................................             100               1              10               1
C...............................................           1,000              10             100              10
D...............................................           5,000             100             500              50
----------------------------------------------------------------------------------------------------------------

    EPA reviewed several options for toxicity endpoints for FWSE. These
included both the Criterion Maximum Concentration (CMC) and Criterion
Continuous Concentration (CCC), as well as a percentage of the LC50 for
acute aquatic toxicity tests. While the CMC and CCC have the advantage
of combining the results of multiple toxicity tests, using overarching
chemical components, there are 104 freshwater CMCs, 116 freshwater
CCCs, 97 saltwater CMCs and 97 saltwater CCCs for CWA hazardous
substance chemical compounds.\23\ EPA solicits comment on methods of
estimating concentrations based on aquatic toxicity testing that are
relevant to human and aquatic endpoints for the 296 CWA regulated
hazardous substances and how to address mixtures, with supporting
rationale and data.
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    \23\ Further information is available in the TBD.
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Planning Distance Parameters

    EPA is proposing in Sec.  118.10(b) that owners or operators shall
use any methodology(ies) or formula(s) that accurately reflect the
conditions at the facility location and that consider parameters
provided by EPA for overland transport and transport over water.
Overland transport parameters shall include ground conditions (e.g.,
topography, land use, soil absorption) and properties of the CWA
hazardous substance (e.g., evaporation, reactivity). In-water transport
parameters include: The point of entry to the water (i.e., flow rate,
duration, direction of the discharge); conditions of the water (i.e.,
velocity, slope, currents, turbulence, water temperature, salinity);
and properties of the CWA hazardous substance in water.
    The proposed approach differs from the Oil Pollution Prevention FRP
program which specifies formulas for calculating planning distance and
allows the owner or operator to use an alternative formula(s) for
calculating planning distance (see 40 CFR part 112 Appendix C,
Attachment C-III). In this action, EPA is proposing flexibility for
determining planning distance for CWA hazardous substances to account
for the variety in chemical and physical properties of the 296 CWA
hazardous substances. EPA determined a one-size-fits-all approach for
calculating planning distances for CWA hazardous substances is not
appropriate for this particular action given the variety of hazardous
substances and the range of physicochemical properties resulting in
differences in their fate and transport. Facility owners and operators
may choose to use existing models and formulas to calculate planning
distance such as those in 40 CFR part 112 Appendix C. The owner or
operator must provide supporting documentation, rationale, and
assumptions for the formula used to calculate planning distance in
order for the EPA to evaluate the facility's determination of
substantial harm.
    EPA explored other potential models for planning distance, which
are further discussed in the TBD, and considered whether the Agency
should specify formulas for calculating planning distance and/or
develop a tool to assist facility owners and operators in completing
calculations. An example of one such tool is RMP*Comp, a free software
program an owner or operator can use to complete the Off-site
Consequence Analyses (both worst case scenarios and alternative
scenarios) required under the RMP rule. RMP*Comp allows a user to input
data elements and then guides the user through the process of
conducting the analysis.
    EPA solicits comment on the various model parameters, in-water and
overland transport models, scenarios, and variables which should be
included in a potential planning distance calculation as well as
whether EPA should develop a comparable tool to the RMP*Comp system for
worst case discharges CWA hazardous substances.
ii. Alternative Approaches
    EPA considered using the same parameter and toxic endpoint approach
as proposed above, except with endpoints established from the CWA RQ
concentrations. In this alternative approach, EPA would use the lower
end of each RQ category concentration range for the toxic endpoint
value. Although this approach ensures that the program remains
consistent by using the RQs, considering both aquatic toxicity and
mammalian toxicity (oral), the range of concentrations for each RQ
category may be too large to accurately reflect the risk of each
substance. EPA solicits comment on this approach and potential
alternatives along with supporting data and rationale.
    EPA also considered specifying formulas by chemical, chemical
category, or some other categorization.

The Agency evaluated existing modeling programs for water and land but
chose not to adopt an approach that specifies formulas for CWA
hazardous substance planning distance.\24\ The chemical and physical
property variation across the 296 CWA hazardous substances make it
challenging to adopt a one-size-fits-all approach to accurately
calculate planning distances. EPA solicits comment on available
technologies, methodologies, modeling programs, or formulas that could
be used to establish planning distance.
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    \24\ Details on the models evaluated are included in the TBD.
---------------------------------------------------------------------------

b. Ability to Adversely Impact a Public Water System
i. Proposed Approach
    EPA is proposing in Sec.  118.3(c)(2) that facilities located at a
distance such that a worst case discharge from the facility has the
ability to adversely impact a public water system could reasonably be
expected to cause substantial harm to the environment. Facilities would
be required to coordinate with the public water system to determine
whether concentrations from a worst case CWA hazardous substance
discharge would result in scenarios adversely impacting the public
water system.
    Public drinking water was specifically highlighted as an area of
risk of substantial harm in the OPA 90 Conference Report under
proximity to potable water.\25\ EPA proposes in Sec.  118.2 to adopt
the definition of public water system as stated in 40 CFR 141.2 and
used by the Oil Pollution Prevention FRP program, designating a public
water system as a system of public piped water for human consumption
with at least fifteen service connections or that regularly services 25
individuals for at least 60 days of the year.
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    \25\ Legislative History of the Oil Pollution Act of 1990:
Public Law 101-380: 104 Stat. 484: August 18, 1990. in 8 Washington,
DC, Covington & Burling; p. 150.
---------------------------------------------------------------------------

    In determining whether a CWA hazardous substance discharge would
adversely impact a downstream public water system, the facility owner
or operator would be required to evaluate whether a worst case
discharge concentration would:
    1. Violate Federal and state drinking water standards (e.g.,
Maximum Contaminant Levels (MCLs)),
    2. Compromise the ability of a public water system to produce water
that complies with Federal and state drinking water standards,
    3. Result in adverse health impacts in individuals exposed to
contaminated drinking water,
    4. Contaminate public water system infrastructure, and/or
    5. Cause a public water system to issue water use restrictions.
    EPA expects that facilities would need to gather relevant
information related to the CWA hazardous substances onsite and
information relevant to their fate and transport following a discharge
in order to determine whether the facility has the ability to adversely
impact public water systems. This may include modeling a worst case
discharge scenario and obtaining the arrival time, duration, and
concentration of the discharge as it reaches a water intake. With that
information, the facility would coordinate with downstream public water
systems to determine impacts to the system and would be required to
document coordination.
    State drinking water primacy agencies (``State agency'') may be
another resource to aid in determining impacts to public water systems.
EPCRA section 304 requires facilities to notify their State Emergency
Response Commission (SERC) or Tribal Emergency Response Commission
(TERC) and Local Emergency Planning Committee (LEPC) or Tribal
Emergency Planning Committee (TEPC) of any releases of extremely
hazardous substances (EHSs) defined under EPCRA section 302 or CERCLA
hazardous substances at or above their RQ. The America's Water
Infrastructure Act (AWIA), which amended EPCRA section 304, requires
facilities to notify the applicable State agency, which in turn
notifies community water systems of a discharge that has the potential
to impact the system's source water. In Appendix A of 40 CFR part 118,
EPA is proposing to require facilities to document and retain efforts
to coordinate with nearby public water systems regarding this
substantial harm criterion.
    All states, except for Wyoming, have primacy for implementing the
Safe Drinking Water Act (SDWA). The EPA Regional Water Program
implements the SDWA for Wyoming, Washington DC, several Indian Tribes,
and the territories. State drinking water primacy agencies are required
to enforce Federal standards. State drinking water programs also have
the discretion to (1) place more stringent standards on contaminants
regulated under SDWA or (2) regulate a contaminant that is not
currently regulated under SDWA. EPA intends the proposed language to
encompass Federal drinking water standards as well as more stringent
state drinking water regulations.
    This general approach covers any site-specific considerations and
contains clear and unambiguous requirements, as well as negates the
need to specify values (i.e., concentration or total mass) that result
in substantial harm; rather, it focuses on adverse outcomes that could
result from a worst case discharge. Additionally, this approach avoids
the issue of whether drinking water treatment could (or could not)
reduce the concentration of the CWA hazardous substance to below
harmful levels.
    EPA recognizes challenges with this approach. First, this approach
places a burden on public water systems to voluntarily participate in
coordination activities with an unknown number of upstream facilities.
A limited number of public water systems could be inundated with
coordination requests depending on the number of potentially regulated
facilities located upstream. Second, public water systems may not fully
understand whether worst-case discharges for particular CWA hazardous
substance would result in adverse health impacts in exposed individuals
or contaminate their infrastructure given the variability of CWA
hazardous substance physiochemical properties and toxicities. This may
be especially true for smaller systems that lack the knowledge and
resources to assist in this evaluation. EPA recognizes that guidance
would need to be developed to support such evaluations. Lastly, given
their variability, the treatability of some CWA hazardous substances is
not known. Further, if a public water system does not respond to
requests to coordinate, facility owners or operators may be in a
position to make the determination without the support and expertise of
water system staff. In these instances, the regulated facility would
measure compliance at the water treatment facility intake. Another
challenge with this approach is that it does not consider other water
intakes (e.g., industrial water intakes) that may be downstream of a
potentially regulated facility. EPA solicits comment on the merits and
limitations of this approach, including situations where a public water
system declines to participate or does not respond; suggested
alternatives to this approach; and supporting data and rationale for
these alternatives.
ii. Alternative Approaches
    EPA considered categorizing all facilities within Source Water
Protection Areas (SWPAs) as meeting substantial harm criteria. The 1996
Amendments to SDWA emphasized the importance of pollution prevention to
protect the safety of drinking water supplies and required states to
create a

Source Water Assessment Program for all public water systems. State
drinking water programs were required to:
    1. Identify the land area(s) which provide water to each public
drinking water source in their state;
    2. Complete an inventory of existing and potential sources of
contamination in those areas;
    3. Determine the susceptibility of each drinking water system to
contamination; and
    4. Distribute the results of the assessment to water users and
other interested entities.
    The 1996 program requirements were intended to provide communities
with the information needed to formulate and implement protection
measures. By the early 2000s, source water assessments were completed
for all public water systems. The 1996 SDWA Amendments do not require
states to update source water assessments periodically. However, some
states opt to implement state-specific policies requiring periodic
evaluations and/or updates of assessments. States may provide access to
public water system source water assessment reports on their websites
or respond to information requests for these reports. Updating
assessment plans by the states is voluntary. As such, states, not EPA,
maintain the information and geographic boundaries of SWPAs.
    For SWPAs that are publicly available, facilities could easily
determine whether they are within a boundary and it would obviate the
need for distance planning. However, EPA chose not to adopt this
approach for several reasons. First, this would increase the number of
facilities that must develop facility response plans without clearly
focusing on those that could cause the greatest harm. Additionally,
many states do not make their SWPAs available to the public, so
facility owners or operators would have to request them from the state.
Responding to these requests could place a burden on state drinking
water programs. Further, EPA does not possess the geographic boundaries
of current state SWPAs, which hinders EPA's ability to assess how
feasible this option would be to implement. This presents challenges to
estimating the facility universe or costs for this approach.