Document ID: EPA-HQ-OLEM-2020-0107-0119
Agency: epa
Document Type: Proposed Rule
Title: Hazardous and Solid Waste Management System: Disposal of Coal Combustion Residuals From Electric Utilities; Legacy CCR Surface Impoundments
Posted Date: 2023-05-18T04:00Z

[Federal Register Volume 88, Number 96 (Thursday, May 18, 2023)]
[Proposed Rules]
[Pages 31982-32044]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-10048]

[[Page 31981]]

Vol. 88

Thursday,

No. 96

May 18, 2023

Part IV

Environmental Protection Agency

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40 CFR Part 257

Hazardous and Solid Waste Management System: Disposal of Coal 
Combustion Residuals From Electric Utilities; Legacy CCR Surface 
Impoundments; Proposed Rule

  Federal Register / Vol. 88, No. 96 / Thursday, May 18, 2023 / 
Proposed Rules  

[[Page 31982]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 257

[EPA-HQ-OLEM-2020-0107; FRL-7814-02-OLEM]
RIN 2050-AH14

Hazardous and Solid Waste Management System: Disposal of Coal 
Combustion Residuals From Electric Utilities; Legacy CCR Surface 
Impoundments

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: On April 17, 2015, the Environmental Protection Agency (EPA or 
the Agency) promulgated national minimum criteria for existing and new 
coal combustion residuals (CCR) landfills and existing and new CCR 
surface impoundments. On August 21, 2018, the United States Court of 
Appeals for the District of Columbia Circuit vacated the exemption for 
inactive surface impoundments at inactive facilities and remanded the 
issue back to EPA to take further action consistent with the opinion in 
Utility Solid Waste Activities Group, et al. v. EPA. The Agency is 
proposing to establish regulatory requirements for inactive surface 
impoundments at inactive facilities (legacy CCR surface impoundments). 
EPA is also proposing to establish groundwater monitoring, corrective 
action, closure, and post-closure care requirements for all CCR 
management units (regardless of how or when that CCR was placed) at 
regulated CCR facilities. EPA is also proposing several technical 
corrections to the existing regulations, such as correcting certain 
citations and harmonizing definitions.

DATES: 
    Comments due: Comments must be received on or before July 17, 2023.
    Public Hearing: EPA will hold an in-person public hearing on June 
28, 2023 and a virtual public hearing on July 12, 2023. Please refer to 
the SUPPLEMENTARY INFORMATION section for additional information on the 
public hearing.

ADDRESSES: You may send comments, identified by Docket ID No. EPA-HQ-
OLEM-2020-0107, 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, Office of Land and Emergency Management (OLEM) Docket, Mail 
Code 28221T, 1200 Pennsylvania Ave. 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.-4:30 p.m., Monday-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.

FOR FURTHER INFORMATION CONTACT: For questions concerning this 
proposal, contact Michelle Lloyd, Office of Resource Conservation and 
Recovery, Materials Recovery and Waste Management Division, 
Environmental Protection Agency, 1200 Pennsylvania Avenue NW, MC: 
5304T, Washington, DC 20460; telephone number: (202) 566-0560; email 
address: [email protected]. For more information on this 
rulemaking please visit https://www.epa.gov/coalash.

SUPPLEMENTARY INFORMATION: 

Table of Contents

I. Public Participation
    A. Written Comments
    B. Participation in In-Person Public Hearing
    C. Participation in Virtual Public Hearing
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 incremental costs and benefits of this action?
III. Background
    A. 2015 CCR Rule
    B. 2018 USWAG Decision
    C. 2020 Advance Notice of Proposed Rulemaking
IV. What is EPA proposing?
    A. Legacy CCR Surface Impoundment Requirements
    B. CCR Management Unit Requirements
    C. Technical Corrections
V. Effect on State CCR Permit Programs
VI. The Projected Economic Impact of This Action
VII. Statutory and Executive Order Reviews
Regulatory Text

List of Acronyms

ACM Assessment of Corrective Measures
ANPRM Advance Notice of Proposed Rulemaking
ASD alternative source demonstration
CAA Clean Air Act
CBI Confidential Business Information
CCR coal combustion residuals
CCRMU coal combustion residuals management unit
CERCLA Comprehensive Environmental Response, Compensation, and 
Liability Act
CFR Code of Federal Regulations
CWA Clean Water Act
EAP Emergency Action Plan
EJ environmental justice
ELG Effluent Limitation Guidelines
EPA Environmental Protection Agency
EPRI Electric Power Research Institute
FR Federal Register
GWMCA groundwater monitoring and corrective action
GWPS groundwater protection standard
HQ hazard quotient
HSWA Hazardous and Solid Waste Amendments
ICR Information Collection Request
LEAF Leaching Environmental Assessment Framework
MCL maximum contaminant level
NAICS North American Industry Classification System
NPDES National Pollution Discharge Elimination System
NPL National Priorities List
NTTAA National Technology Transfer and Advancement Act
OMB Office of Management and Budget
OSHA Occupational Safety and Health Administration
PM particulate matter
PRA Paperwork Reduction Act
PUC Public Utility Commission
QA/QC quality assurance/quality control
RCRA Resource Conservation and Recovery Act
RIA Regulatory Impact Analysis
SSI statistically significant increase
SSL statistically significant level
TDS total dissolved solids
TSCA Toxic Substances Control Act
TSDF Transportation Storage and Disposal Facility
USGS U.S. Geological Survey
USWAG Utility Solid Waste Activities Group
WIIN Water Infrastructure Improvements for the Nation

I. Public Participation

A. Written Comments

    Submit your comments, identified by Docket ID No. EPA-HQ-OLEM-2020-
0107, at https://www.regulations.gov (our preferred method), or the 
other methods identified in the ADDRESSES section. Once submitted, 
comments cannot be edited or removed from the docket. 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.

[[Page 31983]]

The written comment is considered the official comment and should 
include discussion of all points you wish to make. 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.

B. Participation in In-Person Public Hearing

    EPA will begin pre-registering speakers for the hearing upon 
publication of this document in the Federal Register. To register to 
speak at the hearing, please use the online registration form available 
on EPA's CCR website (https://www.epa.gov/coalash) or contact the 
person listed in the FOR FURTHER INFORMATION CONTACT section to 
register to speak at the hearing. The last day to pre-register to speak 
at the hearing will be June 26, 2023. On June 27, 2023, EPA will post a 
general agenda for the hearing on EPA's CCR website (https://www.epa.gov/coalash).
    EPA will make every effort to follow the schedule as closely as 
possible on the day of the hearing; however, please plan for the 
hearings to run either ahead of schedule or behind schedule. 
Additionally, requests to speak will be taken the day of the hearing at 
the hearing registration desk. EPA will make every effort to 
accommodate all speakers who arrive and register, although preferences 
on speaking times may not be able to be fulfilled.
    Each commenter will have five (5) minutes to provide oral 
testimony. EPA encourages commenters to provide EPA with a copy of 
their oral testimony electronically by emailing it to the person listed 
in the FOR FURTHER INFORMATION CONTACT section. EPA also recommends 
submitting the text of your oral comments as written comments to the 
rulemaking docket. If EPA is anticipating a high attendance, the time 
allotment per testimony may be shortened to no shorter than three (3) 
minutes per person to accommodate all those wishing to provide 
testimony and who have pre-registered. While EPA will make every effort 
to accommodate all speakers who do not preregister, opportunities to 
speak may be limited based upon the number of pre-registered speakers. 
Therefore, EPA strongly encourages anyone wishing to speak to 
preregister. Participation in the public hearing does not preclude any 
entity or individual from submitting a written comment.
    EPA may ask clarifying questions during the oral presentations but 
will not respond to the presentations at that time. Written statements 
and supporting information submitted during the comment period will be 
considered with the same weight as oral comments and supporting 
information presented at the public hearing.
    Please note that any updates made to any aspect of the hearing are 
posted online at EPA's CCR website at https://www.epa.gov/coalash. 
While EPA expects the hearing to go forward as set forth above, please 
monitor our website or contact the person listed in the FOR FURTHER 
INFORMATION CONTACT section to determine if there are any updates. EPA 
does not intend to publish a document in the Federal Register 
announcing updates.
    If you require the services of an interpreter or special 
accommodations such as audio transcription, please pre-register for the 
hearing with the person listed in the FOR FURTHER INFORMATION CONTACT 
section and describe your needs by June 14, 2023. EPA may not be able 
to arrange accommodations without advance notice.

C. Participation in Virtual Public Hearing

    EPA will begin pre-registering speakers for the hearing upon 
publication of this document in the Federal Register. To register to 
speak at the hearing, please use the online registration form available 
on EPA's CCR website (https://www.epa.gov/coalash) or contact the 
person listed in the FOR FURTHER INFORMATION CONTACT section to 
register to speak at the virtual hearing. The last day to pre-register 
to speak at the hearing will be July 10, 2023. On July 11, 2023, EPA 
will post a general agenda for the hearing on EPA's CCR website at: 
https://www.epa.gov/coalash.
    EPA will make every effort to follow the schedule as closely as 
possible on the day of the hearing; however, please plan for the 
hearings to run either ahead of schedule or behind schedule. 
Additionally, requests to speak will be taken the day of the hearing 
according to the procedures specified on EPA's CCR website (https://www.epa.gov/coalash) for this hearing. The Agency will make every 
effort to accommodate all speakers who arrive and register, although 
preferences on speaking times may not be able to be fulfilled.
    Each commenter will have five (5) minutes to provide oral 
testimony. EPA encourages commenters to provide the EPA with a copy of 
their oral testimony electronically (via email) by emailing it to 
person listed in the FOR FURTHER INFORMATION CONTACT section. If EPA is 
anticipating a high attendance, the time allotment per testimony may be 
shortened to no shorter than three (3) minutes per person to 
accommodate all those who wish to provide testimony and have pre-
registered. While EPA will make every effort to accommodate all 
speakers who do not preregister, opportunities to speak may be limited 
based upon the number of preregistered speakers. Therefore, EPA 
strongly encourages anyone wishing to speak to preregister. 
Participation in the virtual public hearing does not preclude any 
entity or individual from submitting a written comment.
    EPA may ask clarifying questions during the oral presentations but 
will not respond to the presentations at that time. Written statements 
and supporting information submitted during the comment period will be 
considered with the same weight as oral comments and supporting 
information presented at the public hearing. Verbatim transcripts of 
the hearings and written statements will be included in the docket for 
the rulemaking.
    Please note that any updates made to any aspect of the hearing is 
posted online on EPA's CCR website at https://www.epa.gov/coalash. 
While the EPA expects the hearing to go forward as set forth above, 
please monitor our website or contact the person listed in the FOR 
FURTHER INFORMATION CONTACT section to determine if there are any 
updates. EPA does not intend to publish a document in the Federal 
Register announcing updates.
    If you require the service of a translator, please pre-register for 
the hearing and describe your needs by June 28, 2023. If you require 
special accommodations such as audio transcription or closed 
captioning, please pre-register for the hearing and describe your needs 
by June 28, 2023. We may not be able to arrange accommodations without 
advance notice. Registrants should notify the person listed in the FOR 
FURTHER INFORMATION CONTACT section and indicate on the registration 
form any such needs when they pre-register to speak.

II. General Information

A. Does this action apply to me?

    This rule applies to and may affect all CCR generated by electric 
utilities and independent power producers that fall within the North 
American Industry Classification System (NAICS) code

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221112. The reference to NAICS code 221112 is not intended to be 
exhaustive, but rather provides a guide for readers regarding entities 
likely to be regulated by this action. This discussion lists the types 
of entities that EPA is now aware could potentially be regulated by 
this action. Other types of entities not described here could also be 
regulated. To determine whether your entity is regulated by this 
action, you should carefully examine the applicability criteria found 
in 40 CFR 257.50 of title 40 of the Code of Federal Regulations. If you 
have questions regarding the applicability of this action to a 
particular entity, consult the person listed in the FOR FURTHER 
INFORMATION CONTACT section.

B. What action is the Agency taking?

    EPA is proposing to amend the regulations governing the disposal of 
CCR in landfills and surface impoundments, codified in subpart D of 
part 257 of Title 40 of the Code of Federal Regulations (CFR) (CCR 
regulations). Specifically, the Agency is proposing to establish 
regulatory requirements for inactive CCR surface impoundments at 
inactive utilities (``legacy CCR surface impoundment'' or ``legacy 
impoundment''). This action is being proposed in response to the August 
21, 2018, opinion by the U.S. Court of Appeals for the District of 
Columbia Circuit in Utility Solid Waste Activities Group v. EPA, 901 
F.3d 414 (D.C. 2018) (``USWAG decision'' or ``USWAG'') that vacated and 
remanded the provision exempting legacy impoundments from the CCR 
regulations. This action includes adding a definition for legacy CCR 
surface impoundments and other terms relevant to this rulemaking. It 
also proposes to require that legacy CCR surface impoundments comply 
with certain existing CCR regulations with tailored compliance 
deadlines.
    While this action is responsive to the D.C. Circuit's order, it is 
also driven by the record, which clearly demonstrates that regulating 
legacy CCR surface impoundments will have significant quantified and 
unquantified public health and environmental benefits. As EPA concluded 
in 2015, the risks posed by unlined CCR surface impoundments are 
substantial, and the risks from legacy impoundments are at least as 
significant. EPA's 2014 Risk Assessment concluded that the cancer risks 
from unlined surface impoundments ranged from 3x10 -4 for 
trivalent arsenic to 4x10-5 for pentavalent arsenic. Non-
cancer risks from these same units also significantly exceeded EPA's 
level of concern, with estimated Hazard Quotients (HQ) of two for 
thallium, three for lithium, four for molybdenum and eight for 
trivalent arsenic. In addition, as described in Unit IV.B.1 of this 
preamble, information obtained since 2015 indicates that the risks for 
legacy CCR surface impoundments are likely to be greater than EPA 
originally estimated. Finally, based on the demographic composition and 
environmental conditions of communities within one and three miles of 
legacy CCR surface impoundments, these proposals will reduce existing 
disproportionate and adverse effects on economically vulnerable 
communities, as well as those that currently face environmental 
burdens. For example, in Illinois the population living within 1 mile 
of legacy CCR surface impoundment sites is over three times as likely 
compared to the state average to have less than a high school education 
(35.66% compared to 10.10%, see RIA exhibit ES.14), and that population 
already experiences higher than average exposures to particulate 
matter, ozone, diesel emissions, lifetime air toxics cancer risks, and 
proximity to traffic, Superfund sites, Risk Management Plan sites, and 
hazardous waste facilities (see RIA exhibit ES.15). Following on the 
significant progress EPA has made over many decades to reduce dangerous 
pollution from coal-fired electric utilities' stack emissions and 
effluents, this proposed rule will help EPA further ensure that the 
communities and ecosystems closest to coal facilities are sufficiently 
protected from harm from groundwater contamination, surface water 
contamination, fugitive dust, floods and impoundment overflows, and 
threats to wildlife.
    EPA is also proposing to establish requirements to address the 
risks from currently exempt solid waste management that involves the 
direct placement of CCR on the land.\1\ EPA is proposing to extend a 
subset of the existing requirements in part 257, subpart D to CCR 
surface impoundments and landfills that closed prior to the effective 
date of the 2015 CCR Rule, inactive CCR landfills, and other areas 
where CCR is managed directly on the land. In this proposal, EPA refers 
to these as CCR management units, or CCRMU. This proposal would apply 
to all existing CCR facilities and all inactive facilities with legacy 
CCR surface impoundments subject to this proposed rule.
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    \1\ Regulated CCR units consist of new and existing landfills 
and surface impoundments, including any lateral expansion of these 
units, as well as inactive CCR surface impoundments and legacy CCR 
surface impoundments.
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    Finally, EPA is proposing a number of technical corrections to the 
existing regulations, such as correcting certain citations and 
harmonizing definitions.
    EPA intends that the provisions of the rule be severable. In the 
event that any individual provision or part of the rule is 
invalidated., EPA intends that this would not render the entire rule 
invalid, and that any individual provisions that can continue to 
operate will be left in place.
    In this proposal, EPA is not reconsidering, proposing to reopen, or 
otherwise soliciting comment on any other provisions of the existing 
CCR regulations beyond those specifically identified in this proposal. 
For the reader's convenience, EPA has provided a background description 
of existing requirements in several places throughout this preamble. In 
the absence of a specific request for comment and proposed change to 
the identified provisions, these descriptions do not reopen any of the 
described provisions. EPA will not respond to comments submitted on any 
issues other than those specifically identified in this proposal, and 
such comments will not be considered part of the rulemaking record.

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

    EPA is publishing this notice under the authority of sections 
1008(a), 2002(a), 4004, and 4005(a) and (d) of the Solid Waste Disposal 
Act of 1970, as amended by the Resource Conservation and Recovery Act 
of 1976 (RCRA), as amended by the Hazardous and Solid Waste Amendments 
of 1984 (HSWA) and the Water Infrastructure Improvements for the Nation 
(WIIN) Act of 2016, 42 U.S.C. 6907(a), 6912(a), 6944, 6945(a) and (d).
    RCRA section 1008(a) authorizes EPA to publish ``suggested 
guidelines for solid waste management.'' 42 U.S.C. 6907(a). RCRA 
defines solid waste management as ``the systematic administration of 
activities which provide for the collection, source separation, 
storage, transportation, transfer, processing, treatment, and disposal 
of solid waste.'' 42 U.S.C. 6903(28).
    Pursuant to section 1008(a)(3), the guidelines are to include the 
minimum criteria to be used by the states to define the solid waste 
management practices that constitute the open dumping of solid waste or 
hazardous waste and are prohibited as ``open dumping'' under section 
4005. Only those requirements promulgated under the authority of

[[Page 31985]]

section 1008(a)(3) are enforceable under section 7002 of RCRA.
    RCRA section 4004(a) generally requires EPA to promulgate 
regulations containing criteria distinguishing ``sanitary landfills,'' 
which may continue to operate, from ``open dumps,'' which are 
prohibited. 42 U.S.C. 6944(a); see id. 6903(14), (26); 6945(a). The 
statute directs that, ``at a minimum, the criteria are to ensure that 
units are classified as sanitary landfills only if there is no 
reasonable probability of adverse effects on health or the environment 
from disposal of solid wastes at such facility.'' 42 U.S.C. 6944(a).
    RCRA section 4005(a), entitled ``Closing or upgrading of existing 
open dumps,'' prohibits any solid waste management practices or 
disposal of solid waste that does not comply with EPA regulations 
issued under RCRA section 1008(a) and 4004(a). 42 U.S.C. 6945(a). See 
also 42 U.S.C. 6903(14) (definition of ``open dump''). This prohibition 
takes effect ``upon promulgation'' of any rules issued under section 
1008(a)(3) and is enforceable either through a citizen suit brought 
pursuant to section 7002, or through an EPA enforcement action brought 
pursuant to section 4005(d)(4)(A). See 42 U.S.C. 6945(a), (d)(4)(A) 
(authorizing EPA to use the authority under RCRA section 3008(a) to 
enforce the open dumping prohibition for CCR). RCRA section 4005 also 
directs that open dumps (i.e., facilities out of compliance with EPA's 
criteria), must be ``closed or upgraded.'' Id.
    RCRA section 4005(d)(3) specifies that the regulations in 40 CFR 
part 257, subpart D ``(or successor regulations promulgated pursuant to 
sections 6907(a)(3) and 6944(a) of this title), shall apply to each CCR 
unit'' unless a permit issued by an approved state or by EPA is in 
effect. Similarly, section 4005(d)(6) \2\ provides that:
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    \2\ 42 U.S.C. 6945(d)(6).

a CCR unit shall be considered to be a sanitary landfill for 
purposes of this chapter, including subsection (a), only if the coal 
combustion residuals unit is operating in accordance with [a permit 
issued by EPA or an approved State] or the applicable criteria for 
coal combustion residuals units under part 257 of title 40, Code of 
Federal Regulations (or successor regulations promulgated pursuant 
to sections 6907(a)(3) and 6944(a) of this title).
1. Regulation of Solid Wastes Under RCRA Subtitle D
    Solid wastes that are neither a listed or characteristic hazardous 
waste are subject to the requirements of RCRA subtitle D. Subtitle D of 
RCRA establishes a framework for federal, state, and local government 
cooperation in controlling the management of nonhazardous solid waste. 
The federal role is to establish the overall regulatory direction by 
providing minimum nationwide standards that will protect human health 
and the environment. States may, but are not required to, adopt these 
requirements into their state programs.
    Under RCRA section 4005(a), upon promulgation of criteria under 
section 1008(a)(3), any solid waste management practice or disposal of 
solid waste that constitutes the ``open dumping'' of solid waste is 
prohibited. The federal standards apply directly to the facility (are 
self-implementing) and facilities are directly responsible for ensuring 
that their operations comply with these requirements.
    RCRA section 4005(d) establishes an additional regulatory 
structure, applicable exclusively to the solid waste management of CCR, 
that builds on the provisions in sections 1008(a)(3), 4004, and 
4005(a), without restricting the scope of EPA's authority under those 
sections. See, 42 U.S.C. 6945 (d)(7). Under 4005(d), states may seek 
EPA approval of a state permitting program under which individualized 
facility permits would ``operate in lieu of [EPA] regulation of coal 
combustion residuals units in the State.'' 42 U.S.C. 6945(d)(1)(A). EPA 
is also directed to ``implement a permit program,'' which would operate 
in absence of an approved state program. 42 U.S.C. 6945(d)(2). However, 
the statute makes clear that facilities must continue to comply with 
the federal regulations until a permit issued by either EPA or an 
approved state is in effect. 42 U.S.C. 6945(d)(3), (6).
    RCRA sections 1008(a)(3) and 4004(a) delegate broad authority to 
EPA to establish regulations governing the management of solid waste. 
Under section 4004(a) EPA is charged with establishing requirements to 
ensure that facilities will be classified as sanitary landfills and not 
an open dump ``only if there is no reasonable probability of adverse 
effects on health or the environment from the disposal of solid waste'' 
at the facility. Or in other words, under section 4004(a) EPA is 
charged with issuing regulations to address all ``reasonable 
probabilities of adverse effects'' (i.e., all reasonably anticipated 
risks) to health and the environment from the disposal of solid waste. 
Section 1008(a)(3) expands EPA's authority to address the risks from 
any of the listed activities. Specifically, EPA is authorized to 
establish requirements applicable to ``storage, transportation, 
transfer, processing, treatment, and disposal of solid waste.'' (42 
U.S.C. 6907(a), 6903(28)). Under RCRA, EPA sets these requirements 
without taking cost into account as a factor. See USWAG et al. v. EPA, 
901 F.3d 414, 448-49 (D.C. Cir. 2018) (citing RCRA Section 4004(a)).
    The statute is clear that EPA is authorized to issue regulations to 
address the current risks from previous solid waste management 
activities. EPA explained at length the basis for this conclusion as 
part of the Agency's rationale for regulating inactive impoundments. 
See, 80 FR 21344-21345. See also USWAG, et al. v. EPA, 901 F.3d 414 
(D.C. Cir. 2018). Among other provisions, the statutory definition of 
an ``open dump'' conclusively resolves the question. RCRA defines an 
``open dump'' as ``any facility or site where solid waste is disposed 
of . . . .'' 42 U.S.C. 6903(14). As the D.C. Circuit explained,

    Importantly, while the ``is'' retains its active present tense, 
the ``disposal'' takes the form of a past participle (``disposed''). 
In this way, the disposal itself can exist (it ``is''), even if the 
act of disposal took place at some prior time . . . . Properly 
translated then, an open dump includes any facility (other than a 
sanitary landfill or hazardous waste disposal facility), where solid 
waste still ``is deposited,'' ``is dumped,'' ``is spilled,'' ``is 
leaked,'' or ``is placed,'' regardless of when it might have 
originally been dropped off. See 42 U.S.C. 6903(3), (14). In other 
words, the waste in inactive impoundments ``is disposed of'' at a 
site no longer receiving new waste in just the same way that it ``is 
disposed of'' in at a site that is still operating.

901 F.3d at 440. See also In re Consolidated Consol. Land Disposal 
Regulation Litig., 938 F.2d 1386, 1389 (D.C. Cir. 1991) (EPA's reading 
of the term ``disposal'' in RCRA's Subtitle C, 42 U.S.C. 6924, to 
include ``the continuing presence of waste'' was reasonable); USWAG, 
901 F.3d at 453-54 (Henderson, J., concurring) (same). By the same 
logic, these provisions would authorize EPA to regulate closed units 
that continue to pose risks to health or the environment, for example 
by requiring the owners and operators of such units to remediate any 
contamination from these units, or to take action to prevent such 
contamination.

    The 2016 amendments further confirm EPA's authority over these 
activities. In section 4005, Congress incorporated the 2015 regulations 
into the statute, and expressly stated that the amendments in 4005(d) 
were not intended to limit or restrict the authority already provided 
under sections 1008(a)(3) and 4004(a). See, 42

[[Page 31986]]

U.S.C. 6945(d)(3), (6), (7). EPA also considers that with these 
amendments, Congress has affirmed the Agency's authority to impose the 
kind of requirements established in part 257 (e.g., corrective action 
to remediate groundwater contamination). Moreover, Congress made clear 
that EPA retains the authority to modify or expand these requirements 
as necessary to ensure that the standard in section 4004(a) will 
continue to be met. See, e.g., 42 U.S.C. 6945(d)(1)(A)(i), (3), (6) 
(referencing ``or successor regulations promulgated pursuant to 
sections 6907(a)(3) and 6944(a) of this title'').
    EPA interprets the standard in section 4004(a) to apply equally to 
criteria issued under sections 1008(a)(3) and 4004(a); namely that the 
criteria must ensure that a facility is to be classified as a sanitary 
landfill, and thus allowed to continue to operate, ``only if there is 
no reasonable probability of adverse effects on health or the 
environment'' from either the disposal or other solid waste management 
practices at the facility. Thus, under the combined authority conferred 
by sections 1008(a)(3) and 4004(a), a facility is an ``open dump'' if 
it engages in any activity involving the management of solid waste that 
does not meet the standard in section 4004(a); or in other words, any 
activity involved with the management of solid waste that presents a 
reasonable probability of causing adverse effects on health or the 
environment. EPA also interprets these provisions to authorize the 
establishment of criteria that define the manner in which facilities 
upgrade or close, consistent with the standard in section 4004(a), to 
ensure there will be no reasonable probability of adverse effects on 
health or the environment.

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

    As noted previously, EPA establishes the requirements under RCRA 
sections 1008(a)(3) and 4004(a) without taking cost into account. See, 
USWAG, 901 F.3d at 448-49. This action is expected to result in costs 
amounting to between $356 million and $413 million per year when 
discounting at 3% and 7% respectively.
    Of the $413 million per year estimated at a 7% discount rate, $237 
million is attributable to the requirements for legacy CCR surface 
impoundments, which are subject to the D.C. Circuit's order in USWAG, 
$170 million is attributable to the requirements for CCRMU, and $6 
million is attributable to requirements for landfills. Of the $356 
million per year estimated at a 3% rate, $204 million is attributable 
to the requirements for legacy CCR surface impoundments, $146 million 
is attributable to the requirements for CCRMU, and $6 million is 
attributable to requirements for landfills. The costs of this proposed 
rule are discussed further in the RIA, and include the costs of unit 
closure, corrective action, fugitive dust controls, structural 
integrity inspections, and recordkeeping and reporting. These cost 
estimates are subject to a number of limitations and uncertainties, and 
EPA has, for example, made the conservative assumption that all 
closures will be by removal, which is a simplified but higher-cost 
compliance option.
    This action is expected to result in monetized benefits amounting 
to between $77 million and $49 million per year when discounting at 3% 
and 7% respectively, as well as a variety of unquantified benefits of 
unknown magnitude. Of the $49 million in annualized monetized benefits 
estimated at a 7% discount rate, $30 million is attributable to the 
requirements for legacy CCR surface impoundments, $16 million is 
attributable to the requirements for CCRMU, and $3 million is 
attributable to requirements for landfills. Of the $77 million in 
annualized monetized benefits estimated at a 3% discount rate, $47 
million is attributable to the requirements for legacy CCR surface 
impoundments, $25 million is attributable to the requirements for 
CCRMU, and $5 million is attributable to requirements for landfills. 
The monetized benefits of this proposed rule are discussed further in 
the RIA, and includes partial estimates of the benefits from reduced 
incidents of cancer, avoided intelligence quotient (IQ) losses from 
mercury and lead exposure and the subsequent reduced need for 
specialized education, non-market benefits of water quality 
improvements, and the protection of threatened and endangered species. 
EPA also monetized the benefits of avoided impoundment failures, 
including both ``catastrophic'' failures and smaller-volume releases. 
One example of a severe impoundment failure is the Dan River Steam 
Station failure which occurred in 2014, when a stormwater drainage pipe 
under the inactive surface impoundments at the Dan River Steam Station 
caused the inadvertent release of 39,000 tons of CCR directly into the 
nearby Dan River. The result high-end estimate of the costs of this 
impoundment failure is $300 million. EPA requests comment and data on 
other examples of CCR releases from inactive CCR impoundments.
    EPA's benefits estimates are subject to a number of limitations and 
uncertainties, and many key categories of benefits could not be 
quantified or monetized. Unquantified benefits may be of equal or 
greater magnitude than quantified benefits but are difficult to 
quantify because sufficient data or adequate methodologies are not 
available. For example, EPA was only able to quantify the subset of 
human health effects for which established dose-response relationships 
have been studied and accepted for economic analyses. Consequently, EPA 
was unable to quantify most of the human health and ecological benefits 
associated with the proposed rule. Specifically, EPA was only able to 
quantify the benefits associated with: (1) Reduced incidence of two 
kinds of skin cancer \3\ from exposure to arsenic III and V in drinking 
water from private wells, and (2) With reduced neurologic and cognitive 
damages from exposure to lead and mercury from fish consumption. 
However, arsenic is also correlated with liver, lung, bladder, and 
kidney cancer,\4\ all of which are associated with higher costs and 
higher rates of mortality than the skin cancers used in the quantified 
benefits assessments. Similarly, toxins such as thallium, molybdenum, 
and lithium are commonly present in CCR,\5\ and as discussed in Unit 
IV.B.2 of this preamble, have been detected at statistically 
significant levels at several utilities, but because EPA lacks the data 
to create dose-response relationships between ingestion rates and 
specific health endpoints, EPA could not quantify the associated 
benefits in the RIA. A broad overview of specific contaminants and 
their likely health effects can be found in Chapter 4 of the RIA and in 
Appendix B.
---------------------------------------------------------------------------

    \3\ EPA evaluated basal cell carcinoma and squamous cell 
carcinoma, but was unable to quantify costs associated with Bowen's 
disease (or carcinoma in situ), another of the most common forms of 
skin cancer.
    \4\ U.S. Environmental Protection Agency (2014, December). Human 
and ecological risk assessment of coal combustion residuals. 
Regulation Identifier Number: 2050-AE81, citing U.S. EPA. IRIS 
Chemical Assessment Summary for arsenic, inorganic; CASRN 7440-38-2. 
Last updated December 3, 2002.
    \5\ Id.
---------------------------------------------------------------------------

    Another unquantified benefit arises from the expected increase in 
severe weather events due to climate change. Many legacy impoundments 
and CCRMU are located along rivers or the coast, where they are at risk 
of leaking waste and possibly failing when severe weather causes the 
units to flood and overtop. The proposed rule will address this 
baseline risk by requiring closure

[[Page 31987]]

and corrective action at legacy units and CCRMU. This reduction in risk 
yields potentially significant benefits, however the data and 
methodology to quantify the base rate and post-rule rate of unit 
leakage and failure due to weather related flooding and overtopping are 
not available. Thus, this benefit category is unquantified.
    Finally, another significant source of unquantified benefits comes 
from the protection and remediation of the groundwater contaminated by 
a legacy CCR surface impoundment or CCRMU as at many sites this 
groundwater is a potential future source of drinking water or other 
uses. This is distinct from the benefits associated with reducing the 
risks from contaminants migrating into drinking water wells or surface 
waters, reduced risks that rely on the presence of a receptor. As EPA 
explained in the preamble to the original 1979 regulations, sources of 
drinking water are finite, and future users' interests must also be 
protected. See, 44 FR 53445-53448.
    In the United States, groundwater is the source of drinking water 
for about half the total population; it is about 33% of the water that 
County and city water departments supply to households and businesses. 
It provides drinking water for more than 90% of the rural population 
who do not get their water delivered to them from a county/city water 
department or private water company.\6\ It also provides over 50 
billion gallons per day for agricultural needs. The volume of available 
and useable groundwater is decreasing in many areas of the United 
States.\7\ A significant number of legacy CCR surface impoundments and 
CCRMU are located in areas that, according to the U.S. Geological 
Survey (USGS), are experiencing significant groundwater decline and 
depletion.\8\ For example, EPA estimates that 8 potential legacy CCR 
surface impoundments are located in Iowa, and 20 potential CCRMU are 
located in Illinois (12) and Minnesota (8); USGS has estimated that 
these areas experienced 10-25 cubic kilometers of cumulative annual 
groundwater depletion between 1900 and 2008.\9\ Simply stated, the 
resource is becoming more scarce. Commensurately, the value of 
groundwater as a resource for agriculture, drinking water, and other 
purposes is increasing. In the context of such widespread declines in 
the overall availability of this critical resource, this proposed 
rule--which will increase the supply of potable water by requiring the 
remediation of groundwater contaminated by CCRMU and legacy CCR surface 
impoundments, and by preventing further reductions in the supply of 
useable groundwater from degradation and contamination from CCRMU or 
legacy CCR surface impoundments--is expected to provide significant and 
substantial benefits.
---------------------------------------------------------------------------

    \6\ U.S. Department of the Interior, U.S. Geological Survey, 
https://www.usgs.gov/special-topics/water-science-school/science/groundwater-decline-and-depletion.
    \7\ Id. at https://www.usgs.gov/special-topics/water-science-school/science/groundwater-decline-and-depletion.
    \8\ U.S. Department of the Interior, U.S. Geological Survey, 
Groundwater Depletion in the United States (1900-2008), available at 
https://pubs.usgs.gov/sir/2013/5079/SIR2013-5079.pdf.
    \9\ Id. at 12.
---------------------------------------------------------------------------

    Neighborhoods located near legacy CCR surface impoundments and 
CCRMU are disproportionately occupied by people already vulnerable to 
elevated environmental risks. These vulnerable communities face risks 
of impoundment failure, groundwater contamination, and fugitive air 
emissions. EPA expects these communities would be afforded substantial 
protection from the proposed rule. In addition, CCR units, built 
without liners and other precautionary measures, may depress property 
values in nearby neighborhoods. Improvements in home values resulting 
from the proposed rule has the potential to bestow welfare gains to 
homeowners located near legacy CCR surface impoundments and CCRMU. 
Although EPA has designed its proposal based on its statutory factors 
and court precedent and has not relied on this benefit-cost analysis in 
the selection of its proposed alternative, EPA believes that after 
considering all unquantified and distributional effects, the public 
health and welfare gains that will result from the proposed alternative 
would justify the rule's costs.
    Further information on the economic effects of this action can be 
found in Unit VII of this preamble.

III. Background

A. 2015 CCR Rule

    On April 17, 2015, EPA finalized national minimum criteria for the 
disposal of CCR as solid waste under Subtitle D of RCRA titled, 
``Hazardous and Solid Waste Management System; Disposal of Coal 
Combustion Residuals from Electric Utilities'' (80 FR 21302) (2015 CCR 
Rule). The 2015 CCR Rule, codified in 40 CFR part 257, subpart D, 
established regulations for existing and new CCR landfills, as well as 
existing and new CCR surface impoundments (including all lateral 
expansions of CCR units). The criteria consist of location 
restrictions, design and operating criteria, groundwater monitoring and 
corrective action requirements, closure and post-closure care 
requirements, recordkeeping, notification, and internet posting 
requirements.
    The 2015 CCR Rule also imposed requirements on inactive surface 
impoundments at active facilities. A CCR surface impoundment is a 
natural topographic depression, man-made excavation, or diked area, 
which is designed to hold an accumulation of CCR and liquids, and 
treats, stores, or disposes of CCR. The 2015 CCR Rule defined an 
``inactive CCR surface impoundment'' as ``a CCR surface impoundment 
that no longer receives CCR on or after October 19, 2015, and still 
contains both CCR and liquids on or after October 19, 2015.'' 40 CFR 
257.53. The rule defined ``active facility or active electric utilities 
or independent power producers'' as ``any facility subject to the 
requirements of this subpart that is in operation on October 19, 2015. 
An electric utility or independent power producer is in operation if it 
is generating electricity that is provided to electric power 
transmission systems or to electric power distribution systems on or 
after October 19, 2015. An off-site disposal facility is in operation 
if it is accepting or managing CCR on or after October 19, 2015.'' 40 
CFR 257.53.
    The 2015 CCR Rule did not impose any requirements on inactive 
facilities. EPA explained that this was consistent with past decisions 
under subtitle C, in which EPA declined to extend permitting 
obligations to closed and inactive disposal facilities in light of 
specific language in RCRA sections 3004 and 3005, and the practical 
difficulties in applying those requirements to inactive facilities 
(e.g., the difficulty in identifying owners or other responsible 
parties, and in implementing requirements in the absence of an entity 
currently engaged in disposal). 80 FR 21344 (April 17, 2015). EPA 
further raised concerns that the present owner of the land on which an 
inactive site was located might have no connection (other than present 
ownership of the land) with the prior disposal activities. Id. 
Consequently, EPA exempted those units at Sec.  257.50(e).

B. 2018 USWAG Decision

    The 2015 CCR Rule was challenged by several parties, including 
coalitions of regulated entities and environmental organizations 
(``Environmental Petitioners''). Environmental Petitioners raised two 
challenges that are relevant to this proposal. First, they challenged 
the provision that allowed existing, unlined surface impoundments to 
continue to operate until they exceeded

[[Page 31988]]

the groundwater protection standard. See Sec.  257.101(a)(1). They 
contended that EPA failed to show how continued operation of unlined 
impoundments met RCRA's baseline requirement that any solid waste 
disposal site pose, ``no reasonable probability of adverse effects on 
health or the environment.'' 42 U.S.C. 6944(a). Second, Environmental 
Petitioners challenged the exemption for inactive surface impoundments 
at inactive power plants (i.e., ``legacy ponds''). Environmental 
Petitioners argued that legacy ponds are at risk of unmonitored leaks 
and catastrophic structural failures.
    On August 21, 2018, the U.S. Court of Appeals for the D.C. Circuit 
upheld most of the 2015 CCR Rule but decided in favor of Environmental 
Petitioners on these two claims. The Court held that EPA acted 
``arbitrarily and capriciously and contrary to RCRA'' in failing to 
require the closure of unlined surface impoundments \10\ and in 
exempting inactive surface impoundments at inactive power plants from 
regulation. The Court vacated these provisions and remanded the matter 
back to the Agency for further action consistent with its opinion. 
USWAG et al. v. EPA, 901 F.3d 414 (D.C. Cir. 2018).
---------------------------------------------------------------------------

    \10\ The closure of unlined CCR surface impoundments was 
addressed in a separate regulatory action that was published on 
August 28, 2020 (85 FR 53516).
---------------------------------------------------------------------------

    In overturning the exemption for legacy ponds, the Court evaluated 
the evidence in the rulemaking record and reached specific conclusions 
about the risks that legacy ponds pose. The Court pointed to evidence 
that legacy ponds are most likely to be unlined and unmonitored and 
that such units have been shown to be more likely to leak than units at 
utilities still in operation. 901 F.3d at 432. The Court also 
determined that legacy ponds:

. . . pose the same substantial threats to human health and the 
environment as the riskiest Coal Residuals disposal methods, 
compounded by diminished preventative and remediation oversight due 
to the absence of an onsite owner and daily monitoring. See 80 FR at 
21343 through 21344 (finding that the greatest disposal risks are 
``primarily driven by the older existing units, which are generally 
unlined''). Notably, this very Rule was prompted by a catastrophic 
legacy pond failure that resulted in a ``massive'' spill of 39,000 
tons of coal ash and 27 million gallons of wastewater into North 
Carolina's Dan River.
. . .

    [T]here is no gainsaying the dangers that unregulated legacy 
ponds present. The EPA itself acknowledges the vital importance of 
regulating inactive impoundments at active facilities. That is 
because, if not properly closed, those impoundments will 
``significant[ly]'' threaten ``human health and the environment 
through catastrophic failure'' for many years to come. 75 FR at 
35,177; see also 80 FR at 21,344 n. 40.
    The risks posed by legacy ponds are at least as substantial as 
inactive impoundments at active facilities. See 80 FR at 21,343-21, 
344 (finding ``no [ ] measurabl[e] differen[ce]'' in risk of 
catastrophic events between active and inactive impoundments). And 
the threat is very real. Legacy ponds caused multiple human and 
environmental disasters in the years leading up to the Rule's 
promulgation. See 75 FR at 35,147 (proposed rule discusses multiple 
serious incidents). For example, a pipe break at a legacy pond at 
the Widows Creek plant in Alabama caused 6.1 million gallons of 
toxic slurry to deluge local waterways. Id. Another legacy pond in 
Gambrills, Maryland caused the heavy metal contamination of local 
drinking water. Id. And the preamble to the Rule itself specifically 
points to the catastrophic spill at the Dan River legacy pond in 
North Carolina. 80 FR at 21,393-21,394.

Id. at 432-433. Relying on this evidence, the Court concluded there was 
no logical basis for distinguishing between the inactive impoundments 
at active facilities that were regulated and the legacy impoundments 
that were exempt. Id. at 434. Consequently, the Court vacated the 
provision of the 2015 CCR Rule that specifically exempted inactive 
impoundments at inactive facilities from regulation and remanded the 
matter back to EPA for further action consistent with its opinion. See 
Sec.  257.50(e). Notwithstanding the vacatur of Sec.  257.50(e), until 
EPA amends the regulations to effectuate the Court's order, facilities 
are not legally obliged to take any action to comply with the federal 
CCR regulations. This is because, as currently drafted, Sec.  257.50 of 
the federal CCR regulations is not applicable to inactive surface 
impoundments at inactive facilities.

C. 2020 Advance Notice of Proposed Rulemaking

    On October 14, 2020, EPA published an Advance Notice of Proposed 
Rulemaking (ANPRM) (85 FR 65015). In that action, EPA requested 
information related to ``legacy'' CCR surface impoundments to inform a 
future rulemaking. The Agency requested input on its regulatory 
authority, input on a potential definition of a legacy CCR surface 
impoundment and specific information on the types of inactive surface 
impoundments at inactive facilities that might be considered legacy CCR 
surface impoundments. Specifically, EPA requested information on how 
many of these units exist, the current status of these units (e.g., 
capped, dry, closed according to state requirements, still holding 
water), and the names, locations, and closure dates of former power 
plants that may have these units. Finally, the Agency took comment on 
which CCR regulations should apply to legacy CCR surface impoundments 
and on suggestions for compliance deadlines.
    During the 60-day public comment period, the Agency received over 
15,000 comments from environmental groups, four states, one tribe, 
individual utilities, and industry trade associations. The topics 
raised in comments included a potential definition of a legacy CCR 
surface impoundment, EPA's regulatory authority, the scope and 
applicability of the legacy impoundment rule, and regulatory 
requirements to propose. Moreover, the comments generally agreed that 
EPA must prescribe timeframes for coming into compliance with the 
regulations and they recommended timeframes that are shorter than 
compliance timeframes in the 2015 CCR Rule. The remaining comments 
received are discussed in subsequent units of this preamble.
    As noted, EPA took comment on whether, in light of the Court's 
opinion in USWAG, the Agency could reconsider whether it has the 
authority to regulate inactive impoundments under RCRA subtitle D. 85 
FR 65017-65018 (Oct 14, 2020). The general consensus from commenters on 
the ANPRM was that, because the Court resolved the question based on 
the plain meaning of the statute, EPA does not have the discretion to 
reinterpret its authority. In addition, no commenter identified a 
factual basis for not regulating legacy CCR surface impoundments that 
addressed the Court's concern about the risks these units pose. Id. at 
65018. Consequently, EPA is not revisiting the question of whether it 
may regulate inactive or legacy CCR surface impoundments.

IV. What is EPA Proposing?

    In response to the USWAG decision, EPA is proposing to include a 
provision at Sec.  257.50(e), specifying that inactive surface 
impoundments at inactive facilities (``legacy CCR surface 
impoundments'') are subject to 40 CFR part 257, subpart D. EPA is also 
proposing that owners and operators of legacy CCR surface impoundments 
comply with all the appropriate requirements applicable to inactive CCR 
surface impoundments at active facilities. Specifically, EPA is 
proposing that owners and operators of legacy CCR surface impoundments 
comply with the following existing requirements in the CCR regulations: 
structural stability assessments, air criteria, inspections,

[[Page 31989]]

groundwater monitoring and corrective action, closure and post-closure 
care, recordkeeping, and notification and publicly accessible internet 
site requirements. EPA is further proposing to establish different 
compliance deadlines for these newly applicable regulatory requirements 
to ensure the owners and operators of these units have time to come 
into compliance.
    In addition to the revisions EPA is proposing to address the USWAG 
decision, EPA is proposing to establish requirements to address the 
risks from currently exempt solid waste management that involves the 
direct placement of CCR on the land.\11\ EPA is proposing to extend a 
subset of the existing requirements in part 257, subpart D to CCR 
surface impoundments and landfills that closed prior to the effective 
date of the 2015 CCR Rule, inactive CCR landfills, and other areas 
where CCR is managed directly on the land. In this proposal, EPA refers 
to these as CCR management units, or CCRMU. This proposal would apply 
to all existing CCR facilities and all inactive facilities with legacy 
CCR surface impoundments subject to this proposed rule.
---------------------------------------------------------------------------

    \11\ Regulated CCR units consist of new and existing landfills 
and surface impoundments, including any lateral expansion of these 
units, as well as inactive CCR surface impoundments and legacy CCR 
surface impoundments.
---------------------------------------------------------------------------

    Lastly, EPA is proposing to make several technical corrections to 
the CCR regulations. These are (1) to clarify the definitions of 
``feasible'' and ``technically feasible''; (2) to correct the CFR 
reference in the definition of wetlands at Sec.  257.61(a); (3) to 
correct a reference in the groundwater monitoring scope section; (4) to 
standardize the references to CCR websites throughout the CCR 
regulations; and (5) EPA is taking comment on extending the period for 
document retention and posting.
A. Legacy CCR Surface Impoundment Requirements
    The Agency is proposing that the existing requirements of the CCR 
regulations in 40 CFR part 257, subpart D that apply to inactive CCR 
impoundments at active facilities would apply to legacy CCR surface 
impoundments, except for the location restrictions and liner design 
criteria. EPA is also proposing to establish new requirements to 
address issues specific to legacy CCR surface impoundments. Finally, 
EPA is proposing to establish new compliance deadlines for legacy CCR 
surface impoundments.
1. Scope--Definition of Legacy CCR Surface Impoundments
    EPA received numerous comments on three options for defining legacy 
CCR surface impoundments in the ANPRM. The Agency considered those 
comments, as well as the other information available to EPA in the 
record and the USWAG decision in developing this proposal. Based on 
EPA's review, the Agency is proposing to define a legacy CCR surface 
impoundment as ``a surface impoundment that is located at a power plant 
that ceased generating power prior to October 19, 2015, and the surface 
impoundment contained both CCR and liquids on or after the effective 
date of the 2015 CCR Rule (i.e., October 19, 2015).'' This Unit of the 
preamble also responds to comments questioning how EPA intends to 
interpret ``contains liquids and CCR'' and ``inactive facility.''
a. Legacy CCR Surface Impoundment--Date for Determining Applicability.
    As previously explained, the 2015 CCR Rule exempted ``inactive 
surface impoundments at an inactive facility'' and provided definitions 
of an ``inactive CCR surface impoundment'' and an ``active facility or 
active electric utility.'' See 80 FR 21469-21471. Thus, in developing a 
definition of a legacy CCR surface impoundment two separate components 
need to be addressed: (1) The definition of an ``inactive CCR surface 
impoundment,'' and (2) The definition of an ``inactive facility or 
electric utility.'' EPA relied on the existing definitions of an 
inactive CCR surface impoundment and an active facility or active 
electric utility, as well as the USWAG decision to inform the options 
provided in the ANPRM. See 80 FR 21469-21471. Specifically, both terms 
establish applicability based in part on the effective date of the 2015 
CCR Rule--a unit is an ``inactive CCR surface impoundment'' if it does 
not receive CCR on or after October 19, 2015, and still contains both 
CCR and liquids on October 19, 2015, and an ``active facility or active 
electric utilities or independent power producers'' is only active if 
it was in operation on October 19, 2015. 40 CFR 257.53. Thus, the ANPRM 
sought comment on whether to define a legacy CCR surface impoundment 
as: A surface impoundment that is located at a power plant that ceased 
generating power prior to October 19, 2015, and
     Option 1--the surface impoundment contained both CCR and 
liquids on the effective date of the 2015 CCR Rule (i.e., October 19, 
2015); or
     Option 2--the surface impoundment contained both CCR and 
liquids on the date the Court issued its mandate for the August 21, 
2018, court decision (i.e., October 15, 2018); or
     Option 3--the surface impoundment contains both CCR and 
liquids on the date EPA issues a final rule bringing legacy CCR surface 
impoundments under the federal regulations.
i. Description of the ANPRM Options
    Option 1 was based on October 19, 2015, which is the effective date 
of the 2015 CCR Rule. Under this approach a CCR surface impoundment at 
an inactive facility or electric utility that contained both CCR and 
liquids on October 19, 2015, would be regulated as a legacy CCR surface 
impoundment. Impoundments that contained both CCR and liquids prior to 
October 19, 2015, but not after this date, would not be subject to the 
new requirements under this option (e.g., the facility took actions 
prior to October 19, 2015, to permanently remove liquids from the 
unit).
    The first option is based on the Court's finding in the USWAG 
decision that there was no basis in the record on which to 
differentiate between legacy CCR surface impoundments and inactive CCR 
surface impoundments at active facilities in the 2015 CCR Rule. In the 
decision, the Court concluded there was no logical basis for 
distinguishing between inactive impoundments at active facilities that 
were regulated and inactive impoundments at inactive facilities that 
were exempt, and therefore vacated the exemption for legacy CCR surface 
impoundments in Sec.  257.50(e). In the regulations, an inactive CCR 
surface impoundment at an active facility is defined as a ``CCR surface 
impoundment that no longer receives CCR on or after October 19, 2015, 
and still contains both CCR and liquids on or after October 19, 2015.'' 
Thus, under Option 1 the date the unit contained both CCR and liquids 
used in the definition of a legacy CCR surface impoundment would be 
identical to that used for inactive impoundments at active facilities, 
that is, October 19, 2015.
    Option 2 was based on October 15, 2018, which is the date the Court 
issued the mandate for the USWAG decision that vacated and remanded the 
regulatory provision exempting legacy CCR surface impoundments from the 
CCR regulations. Under this approach a CCR surface impoundment at an 
inactive facility or electric utility that contained both CCR and 
liquids on October 15, 2018, would be regulated as

[[Page 31990]]

a legacy CCR surface impoundment. Impoundments that contained both CCR 
and liquids prior to October 15, 2018, but not after this date, would 
not be subject to the new requirements under this option (e.g., the 
facility took actions prior to October 15, 2018, to permanently remove 
liquids from the unit).
    Option 3 was based on the effective date of a final rule bringing 
legacy CCR surface impoundments under the federal CCR regulations. 
Under this approach a CCR surface impoundment at an inactive facility 
or electric utility that contained both CCR and liquids on the 
effective date of the final rule would be regulated as a legacy CCR 
surface impoundment. Impoundments that contained both CCR and liquids 
prior to the effective date of the final rule, but not after this date, 
would not be subject to the new requirements.
    Underpinning Option 3 is the concept that it may be difficult for 
some owners and operators of inactive facilities to determine whether a 
legacy CCR surface impoundment at its facility previously contained 
both CCR and liquids at a specific point in the past. For example, 
under Options 1 and 2, the demarcation date in the definition will be 
approximately nine and six years in the past, respectively, at the time 
the final rule is anticipated to be published and effective. 
Furthermore, the third option could eliminate possible regulatory 
confusion for legacy CCR surface impoundments that contained liquids 
and CCR on the demarcation date specified in the definition (e.g., 
October 19, 2015, under Option 1) but are subsequently closed by the 
effective date of the final rule. An example of this situation using a 
cutoff date based on Option 1 would be a legacy CCR surface impoundment 
that was closed by removal of CCR in 2020. Under Option 3 the legacy 
CCR surface impoundment in this example would not be subject to the new 
rulemaking requirements because it did not contain both CCR and liquids 
on or after the effective date of the legacy CCR surface impoundment 
final rule.
    Of the three options discussed in the ANPRM, EPA believes that 
Option 1 is arguably the most consistent with the USWAG decision and 
the most protective option. As discussed in the preceding Unit, the 
Court expressly found that EPA's record for the 2015 CCR Rule 
demonstrated that legacy ponds ``pose the same substantial threats to 
human health and the environment as the riskiest Coal Residuals 
disposal methods, compounded by diminished preventative and remediation 
oversight due to the absence of an on-site owner and daily 
monitoring.'' 901 F.3d at 432. Under Option 1 there would be no 
distinction between legacy CCR surface impoundments and the currently 
regulated inactive impoundments at active facilities. In addition, the 
intended effect of a vacatur is to restore the status quo, to what it 
would have been if the vacated provision had never existed. Here, that 
means legacy CCR surface impoundments would have been regulated by the 
2015 CCR Rule. By choosing to vacate the provision, rather than 
remanding it back to the Agency, the Court made clear that its intent 
was for these units to immediately be subject to regulation. The fact 
that the vacatur did not achieve that does not change the court's 
intent.
ii. What comments did EPA receive on the options?
    Summary of Comments on Option 1. Some commenters stated that 
inactive surface impoundments at inactive facilities should be treated 
no differently than active and inactive surface impoundments at active 
facilities. These commenters therefore supported Option 1 and explained 
that the regulations should similarly apply to inactive impoundments at 
inactive facilities containing CCR and liquids on October 19, 2015. 
Other commenters opposed Option 1 because they considered that it would 
represent the retroactive application of regulations and, in some 
cases, the application of fundamentally inapplicable requirements to 
units that are no longer surface impoundments because they no longer 
contain CCR and/or liquids. These commenters identified impoundments 
that have been dewatered, excavated, and closed pursuant to state 
oversight as an example of impoundments that would not be appropriate 
candidates for subsequent regulatory requirements because these units 
are no longer functioning as impoundments based on actions taken by 
facilities since October 19, 2015.
    Other commenters stated that the definition for Option 1 (as well 
as Options 2 and 3) was too narrow and fails to address the universe of 
inactive impoundments at inactive facilities that pose a reasonable 
probability of adverse effects on health or the environment from the 
disposal of CCR. According to the comments, this is because Option 1 
conditions regulation of legacy CCR surface impoundments on arbitrary 
dates on which the impoundments contained both CCR and liquids. These 
commenters stated that the definition must include high-risk 
impoundments (such as impoundments located in floodplains and unstable 
areas and units with bases inundated by groundwater), regardless of age 
or condition, because of the likelihood that they are causing or will 
cause adverse effects to health and the environment, including 
impoundments located in floodplains and unstable areas and units with 
bases inundated by groundwater. In addition, the commenters state that 
the definition of a legacy CCR surface impoundment must include units 
that were not closed in a manner consistent with the regulations 
because a unit without a sufficient final cover system will allow 
precipitation into the unit and will produce leachate.
    Summary of Comments on Option 2. No commenters exclusively 
supported Option 2 over the other two options discussed in the ANPRM. 
Commenters disfavoring Option 2 did so for the same reasons as 
summarized for Option 1, largely stating that Option 2 ignores the 
current status of legacy CCR surface impoundments, inaccurately 
assesses current risks from these units, and disregards work and 
actions taken by facilities since August 21, 2018 (e.g., removal of 
waste from the units, closure of the units). In addition, other 
commenters stated that Option 2 fails to meet the RCRA protectiveness 
standard for reasons discussed under Option 1.
    Summary of Comments on Option 3. Several commenters supporting 
Option 3 stated that the definition of legacy CCR surface impoundments 
should be based on the scope of units identified in the 2018 USWAG 
decision. These commenters explained that the Court was concerned with 
the risks associated with lack of regulatory oversight over inactive 
CCR surface impoundments that contain impounded water, and therefore 
EPA's definition of a legacy CCR surface impoundment should similarly 
be those impoundments containing CCR and liquids on the effective date 
of the legacy CCR surface impoundment final rule. Finally, commenters 
stated that it is both impractical and unnecessary to look backwards to 
determine the historic regulatory status of a unit (e.g., to determine 
whether the impoundment contained CCR and liquids at a particular 
time), or to require impoundments that have already closed to re-close 
under this rulemaking.
    Some commenters said that Option 3 would avoid inclusion of 
effectively dry impoundments that are similar to inactive CCR 
landfills, which are not regulated under the 2015 CCR Rule. Another 
commenter stated that units maintained by its members provide good 
examples of units that it believed

[[Page 31991]]

would not be appropriate candidates for new federal CCR regulation as 
legacy CCR surface impoundments. For instance, the commenter pointed to 
the units at the Riverbend Steam Station in Mount Holly, North 
Carolina, which the commenter stated underwent dewatering from 2014 
through 2019 as part of the excavation process. In accordance with the 
facility's NPDES permit, the water was pumped to the on-site wastewater 
treatment facility for eventual discharge to the adjacent waterbody. 
Ash removal began in 2015 and was completed in 2019. The two ash basins 
at the Riverbend Steam Station have been excavated, and the dams for 
the facility's primary and secondary ash basins have been removed. 
According to the commenter, groundwater monitoring subject to state 
regulations and state-approved closure plans is ongoing. Finally, the 
commenter stated that the site has been regraded and seeded with grass. 
The commenter also pointed to Scholz Electric Generating Plant in 
Sneads, Florida, which has a 40-acre unit that was retired in April 
2015 and ceased receipt of waste in 2015. According to the commenter, 
the facility is currently in its third year of closure construction and 
is subject to a June 2015 court-approved settlement agreement for 
closure as well as an August 2016 closure plan approved by the Florida 
Department of Environmental Protection.
    The commenter also referenced the ash slurry settling ponds at the 
active Coronado Generating Station located in Saint Johns, Arizona. 
According to the commenter, the ponds, which are approximately 87 acres 
in size, were constructed in the mid-2000s and operated until early 
2010 when the facility ceased placement of CCR material in the ponds. 
When in use, the ponds were utilized for CCR and non-CCR waste 
disposal, non-recyclable plant wastewater, scrubber sludge, and fly 
ash, all of which were wet sluiced to the ponds. The commenter stated 
that closure of the ponds was completed in April 2019 in accordance 
with all applicable State of Arizona Aquifer Protection Permitting 
(APP) rules, and all required CCR and APP documentation have been 
posted to the CCR public website and submitted to the Arizona 
Department of Environmental Quality (ADEQ). The commenter also stated 
that the ponds are currently in post-closure care in accordance with 
ADEQ APP regulations, including groundwater monitoring and reporting 
that will continue for 30 years from the date of closure. According to 
the commenter, none of these units are currently functioning as ponds, 
and therefore regulating these types of units at inactive plants would 
represent a retroactive application of inapplicable and redundant 
requirements. The commenter further stated that many utilities are in 
the process of dewatering and closing additional legacy CCR surface 
impoundments as part of a comprehensive, fleetwide ash basin closure 
program.
iii. Response to Comments and Proposed Option
    As noted above, the Agency is proposing to define a legacy CCR 
surface impoundment, in part, as a surface impoundment that contained 
both CCR and liquids on or after October 19, 2015. Of the three options 
discussed in the ANPRM, EPA believes that Option 1 is the most 
consistent with the USWAG decision. As discussed in the preceding Unit, 
the Court expressly found that EPA's record for the 2015 CCR Rule 
demonstrated that legacy ponds ``pose the same substantial threats to 
human health and the environment as the riskiest Coal Residuals 
disposal methods, compounded by diminished preventative and remediation 
oversight due to the absence of an on-site owner and daily 
monitoring.'' 901 F.3d at 432. Under Option 1 there would be no 
distinction between legacy CCR surface impoundments and the currently 
regulated inactive impoundments at active facilities. In addition, the 
intended effect of a vacatur is to restore the status quo, to what it 
would have been if the vacated provision had never existed. Here, that 
means legacy CCR surface impoundments would have been regulated by the 
2015 CCR Rule. By choosing to vacate the provision, rather than 
remanding it back to the Agency, the Court made clear that its intent 
was for these units to immediately be subject regulation. The fact that 
the vacatur did not achieve that does not change the Court's intent.
    In addition, EPA is not persuaded by the commenters' objections to 
this option. EPA disagrees that reliance on the effective date of the 
2015 CCR Rule would constitute a retroactive application of law. For a 
regulation to be retroactive, it must change the prior legal status or 
consequences of past behavior. See Landgraf v. USI Film Products, 511 
U.S. 244, 269, n.4 (1994) (A rule ``is not made retroactive merely 
because it draws upon antecedent facts for its operation.''); Treasure 
State Resource Industry Ass'n v. E.P.A., 805 F.3d 300, 305 (D.C. Cir. 
2015). By contrast, here EPA is merely proposing to rely on a past fact 
to support the future application of regulations. And because EPA is 
proposing to establish future compliance dates, no facility would be 
subject to penalties solely because one of its legacy CCR surface 
impoundments was out of compliance with the regulatory requirements 
prior to the effective date of a rule finalizing this proposal.
    EPA also disagrees that the proposed requirements fail to account 
for the current characteristics of some of these units. The fact that 
some utilities have begun to close, or even completed closure does not 
necessarily resolve the risks these units can pose to groundwater. The 
record shows that significant numbers of CCR surface impoundments were 
constructed such that the base of the unit intersects with groundwater, 
and that many ``closed'' impoundments, even those closed in accordance 
with state permits, continue to impound water below the water table 
(i.e., contain liquid). The risks associated with such closures can be 
substantial (see Unit IV.B.1.b of this preamble for more information). 
Also, as discussed below in further detail, EPA is proposing that units 
that can demonstrate that they have met the performance standards for 
closure by removal in Sec.  257.102(c) would be subject to no further 
requirements.
    Finally, EPA recognizes that in some instances it may take some 
work to determine whether a surface impoundment previously contained 
both CCR and liquids on or after October 19, 2015. However, owners and 
operators of inactive power plants will be able to rely on operating 
records from when the power plant was operational, such as aerial 
photography, construction or inspection reports, groundwater monitoring 
data and employee testimonials to determine whether the impoundment 
contained both CCR and liquids on October 19, 2015.
    Nevertheless, EPA also continues to consider, as an alternative, 
defining a legacy CCR surface impoundment as a CCR surface impoundment 
that no longer receives CCR but contains both CCR and liquids on or 
after the effective date of the final rule. This option would be the 
easiest to implement. Based on the Agency's interpretation of what it 
means ``to contain liquid'' this option would at most only exclude the 
29 units \12\ that may have completed clean closure in accordance with 
the performance standards in Sec.  257.102(c) or have taken steps to 
remove all free

[[Page 31992]]

liquids, including groundwater, and address infiltration. and would 
therefore be equivalent to inactive landfills. While the latter 
category could still present the risk of contaminating groundwater, it 
is possible those risks could potentially be addressed by the proposed 
expansion of groundwater monitoring, corrective action, and closure 
obligations applicable to CCR management units. EPA therefore requests 
further comment on this option.
---------------------------------------------------------------------------

    \12\ This information can be found in the document titled 
``Potential Legacy CCR Surface Impoundments'' in the docket for this 
action.
---------------------------------------------------------------------------

b. Legacy CCR Surface Impoundment--Contains Both Liquid and CCR
    In response to EPA's ANPRM, some commenters stated that the phrase 
``contain[ing] both CCR and liquids'' is impermissibly vague. These 
commenters believe that while it is clear that impoundments that 
currently contain visible, standing water would fit this definition, 
they are concerned that arguments can be made that the definition does 
not include those units whose bases are in contact with groundwater or 
that no longer have standing water at the surface. Other commenters 
stated that more clarity is required regarding the definition of a 
legacy CCR surface impoundment. Finally, several commenters argued that 
EPA should not limit its regulation to units that contain water, but 
should expand the regulation to apply to all CCR units.
i. What does it mean to contain liquid?
    The ANPRM suggested that EPA would only revisit the date on which 
the determination would be made as to whether the impoundment contains 
both CCR and liquids. EPA did not indicate that the Agency intended to 
propose to limit or revise the existing requirement that in order to be 
considered an inactive CCR surface impoundment, the unit must contain 
both liquid and CCR. 40 CFR 257.53. However, as noted above, commenters 
have raised concerns that the existing definition is ambiguous and have 
raised questions about how these existing regulations apply to a number 
of factual scenarios. Specifically, commenters questioned whether the 
term ``liquids'' includes free water, porewater, standing water, and 
groundwater in CCR units.
    The part 257 regulations do not include a definition of the term 
``liquids.'' 40 CFR 257.53. Neither does RCRA define the term. See, 42 
U.S.C. 6903. EPA therefore relies upon dictionary definitions to 
interpret the regulation. For example, Merriam-Webster defines it as 
``a fluid (such as water) that has no independent shape but has a 
definite volume and does not expand indefinitely and that is only 
slightly compressible.'' Similarly, liquid (in physics) can be defined 
as one of the three principal states of matter, intermediate between 
gas and solid. The most obvious physical properties of a liquid are its 
retention of volume and its conformity to the shape of its container. 
Liquid can flow, and when a liquid substance is poured into a container 
or vessel, it takes the shape of that vessel, and will remain that way 
if conditions are unchanged (e.g., the substance stays in the liquid 
state). Furthermore, when a liquid is poured from one vessel to 
another, it retains its volume (if there is no vaporization or change 
in temperature) but not its shape. These properties serve as useful 
criteria for distinguishing the liquid state from the solid and gaseous 
states.
    In the realm of CCR surface impoundments, several types of liquids 
may be present in a CCR unit. For example, among others, this may 
include water that was sluiced into the impoundment along with the CCR, 
which may be found as free water ponded above the CCR or porewater 
intermingled with the CCR, or surface water and groundwater that has 
migrated into the impoundment due to the construction of the unit. 
Based on the regulatory terms, the structure, and context in which the 
terms are employed, as well as the dictionary definitions of 
``liquid,'' above, and the fact that nothing in the regulatory 
definition limits the source of the liquid, EPA considers free water, 
porewater, standing water, and groundwater to be liquids under the 
existing regulation. Moreover, the source of the liquid is not 
important with respect to its basic and fundamental designation as a 
liquid. It therefore does not matter whether the liquid in the surface 
impoundment comes from the rain, waters the facility deliberately 
places in the unit, floodwaters from an adjacent river, or from 
groundwater--all are liquids, and once present in the unit, they have 
the same potential to create leachate (another type of liquid), as well 
as to contribute to hydraulic head and drive flows driven by hydraulic 
gradients.
    Commenters questioned whether the existing definition of an 
inactive CCR surface impoundment would cover a surface impoundment 
where, prior to October 19, 2015, the facility has decanted the surface 
water, but, because the base of the impoundment intersects with the 
aquifer, water continues to flow through the impoundment and permeate 
the waste in the base of the unit. Commenters also questioned whether 
any of the following would also be covered: (a) Impoundments that 
contained CCR and liquids in the past but are now closed, (b) 
Impoundments that contained CCR and liquids in the past but will be in 
the process of closing by the effective date of the legacy rulemaking, 
and (c) Impoundments that once contained CCR and liquids but have been 
fully dewatered and are now maintained so as to not contain liquid.
    The critical issue in these questions is whether on or after the 
relevant date in the regulation these units ``contain'' liquid. 
``Contains'' means ``to have or hold (someone or something) within'' 
(e.g., Oxford English Dictionary, Merriam-Webster). Accordingly, an 
impoundment ``contains'' liquid if there is liquid in the impoundment, 
even if the impoundment does not prevent the liquid from migrating out 
of the impoundment. In other words, it ``contains'' water if it has 
water within, even if it does not completely restrain the water within 
the unit.
    A surface impoundment that, on or after October 19, 2015, has only 
decanted the surface water would normally still contain liquid if waste 
is saturated with water. To the extent the unit still contains liquids, 
it would be covered by the existing definition of an inactive 
impoundment. Under this proposed rule, such units would also be 
considered legacy CCR surface impoundments when located at inactive 
facilities. This would apply whether the unit is considered ``closed'' 
under state law, is in the process of closing, or whether at some 
subsequent point, the unit is fully dewatered and no longer contains 
liquid.
    To determine whether an impoundment has only been partially 
dewatered, EPA relies on the dewatering requirement found in the 
closure performance standard at Sec.  257.102(d)(2)(i) (``Free liquids 
must be eliminated by removing liquid wastes or solidifying the 
remaining wastes and waste residues''). Both the definition of an 
inactive CCR surface impoundment and the closure performance standard 
are designed to address the same issues (the presence or removal of 
liquid wastes) and are designed for the same purpose (to ensure the 
risks from the co-management of CCR and liquid are adequately 
addressed). Under the closure performance standard, a facility must 
eliminate both the standing liquid in the surface of the impoundment 
and the separable porewater in any sediment located in the base of the 
impoundment. Free liquids are defined at Sec.  257.53 to mean ``liquids 
that readily separate from the solid portion of a waste under ambient 
temperature and pressure.'' This definition encompasses both

[[Page 31993]]

standing liquids in the impoundment as well as porewater in any 
sediment or CCR. The regulation does not differentiate between the 
sources of the liquid in the impoundment (e.g., surface water 
infiltration, sluice water intentionally added, groundwater intrusion). 
This is further supported by the fact that the performance standard at 
Sec.  257.102(d)(2)(i) was modeled on the regulations that apply to 
interim status hazardous waste surface impoundments, which are codified 
at Sec.  265.228(a)(2)(i). Available guidance on these interim status 
regulations clarifies that these regulations require both the removal 
of standing liquids in the impoundment as well as sediment dewatering. 
See ``Closure of Hazardous Waste Surface Impoundments,'' publication 
number SW-873, September 1982. See also, Final Decision on Request For 
Extension of Closure Date Submitted by Gavin Power, LLC, 87 FR 72989 
(November 15, 2022).
    Accordingly, units that contain both CCR and liquids from any 
source, including those specifically identified above, after the 
relevant date would be considered inactive CCR impoundments, consistent 
with the existing regulations. Although EPA considers that the term 
``liquids'' is sufficiently clear that a definition is not necessary, 
EPA requests comment on whether it would be useful to include a 
regulatory definition of liquids.
    Under the existing regulations, an impoundment that did not contain 
liquids prior to the effective date of the 2015 CCR Rule, whether 
because it was closed in accordance with existing state requirements or 
for other reasons, is not an inactive impoundment. Similarly, a unit 
that still contains CCR and liquid after the relevant effective date 
would still be considered an inactive unit even if it was closed in 
accordance with the requirements in effect at the time (e.g., has a 
cover). EPA is not proposing to revise this for inactive impoundments, 
and for consistency, EPA is proposing that the same would hold true for 
legacy CCR surface impoundments, whatever date EPA ultimately selects 
for the definition.
    However, EPA also received comments in response to the ANPRM 
stating that available groundwater monitoring data demonstrates that 
CCR landfills (whether active or inactive) are just as likely to 
contaminate groundwater as CCR surface impoundments (legacy or 
otherwise). Accordingly, the commenters argue that EPA should regulate 
all CCR units, without regard to whether they contain liquid.
    EPA is not proposing to expand the definition of a legacy CCR 
surface impoundment to include units that contain no liquid. Units that 
contain liquid present different risks than those that do not, and the 
applicable requirements should differentiate among them accordingly on 
that basis. While EPA acknowledges that inactive landfills can still 
present the risk of contaminating groundwater, it is possible those 
risks could potentially be addressed by this rule's proposed expansion 
of groundwater monitoring, corrective action, and closure obligations 
to CCR management units. EPA acknowledges that its current proposal 
would not regulate every inactive CCR landfill, e.g., it would not 
address any inactive landfill located at an inactive utility that did 
not also have an inactive CCR surface impoundment, but it is unclear 
how many of such units exist, and whether there are any reasons that 
the risks from these units may differ from those that EPA is proposing 
to regulate. EPA therefore requests comment on these issues.
i. What does it mean to ``contain'' CCR?
    Under the existing regulation, an inactive CCR surface impoundment 
must contain CCR to be subject to the rule. 40 CFR 257.53. EPA is not 
proposing to revise that aspect of the term's definition. Consequently, 
EPA is proposing that a legacy impoundment that has closed by removal 
in accordance with the performance standards in Sec.  257.102(c) before 
the relevant date would not be considered an inactive CCR surface 
impoundment. EPA is proposing that facilities with such a unit would 
only be required to post documentation that they have met the existing 
standard for closure by removal in Sec.  257.102(c) on their CCR 
website. EPA is also proposing, however, that an impoundment at an 
inactive facility still undergoing closure by removal on the relevant 
date would be considered a legacy CCR surface impoundment subject to 
the final rule requirements. Depending on when the impoundment 
completes closure, some individual requirements may no longer be 
applicable to the legacy CCR surface impoundment (i.e., when the 
compliance date in the final rule falls after the date closure is 
completed for the impoundment); but EPA has no basis for concluding 
that a legacy CCR surface impoundment that is still in the process of 
closing poses no risk.
    A commenter asserted that EPA's authority under RCRA only extends 
to those impoundments where solid waste is still being ``disposed of'' 
at such inactive sites. According to the commenter, EPA's authority 
ends once the solid waste is removed from the inactive impoundment. The 
commenter cites the USWAG decision to support this interpretation, 
noting that the Court states that an impoundment regulated under RCRA 
includes:

any facility . . . where solid waste still ``is deposited,'' ``is 
dumped,'' ``is spilled,'' ``is leaked,'' or ``is placed,'' 
regardless of when it might have originally been dropped off.'' See 
42 U.S.C. 6903(3), (14). . . A site where garbage ``is disposed of'' 
is the place where garbage is dumped and left. The status of the 
site does not depend on whether or not more garbage is later piled 
on top. A garbage dump is a garbage dump until the deposited garbage 
is gone.

    The commenter concludes that, following the Court's logic, a legacy 
CCR surface impoundment is regulated under RCRA because CCR is 
currently deposited and stored at the site, but it remains an 
impoundment regulated under RCRA only during the time CCR is actually 
being stored at the site. According to the commenter, once all the CCR 
is removed from the impoundment and the impoundment site has achieved 
clean closure status according to state regulators, no CCR is being 
disposed as a solid waste at the site and consequently the impoundment 
is no longer subject to federal CCR regulation under Subtitle D of 
RCRA. By contrast, another commenter relied on the USWAG decision to 
conclude that EPA must regulate all legacy CCR surface impoundments 
unless the facility demonstrates that the unit has complied with the 
requirements in Sec.  257.102(c). According to the commenter, the Court 
explained that ``the statute creates a binary world: A facility is a 
permissible sanitary landfill, or it is an impermissible open dump. The 
EPA regulates both. The timing or continuation of disposal is 
irrelevant.''
    EPA agrees that it no longer has jurisdiction over a former unit 
that has closed by removal in accordance with Sec.  257.102(c). Once 
those standards have been met, no CCR ``still `is deposited,' `is 
dumped,' `is spilled,' `is leaked,' or `is placed.''' This is 
consistent with EPA's proposal to require the owner or operator to 
document that the unit has closed in accordance with Sec.  257.102(c), 
but to impose no requirements on such units.
    Nevertheless, EPA is unable to accept the suggestion that EPA 
exempt legacy CCR surface impoundments that have met state requirements 
for clean closure. The commenter did not provide any information about 
any of the state requirements they reference, or otherwise provide 
information that would allow EPA to evaluate how the

[[Page 31994]]

individual state requirements compare to Sec.  257.102(c). Based on the 
current record EPA can only support a determination that units that 
have clean closed since 2015 under a state CCR permit program meet the 
closure requirements in Sec.  257.102(c) for those facilities operating 
under a permit issued pursuant to one of the three approved state CCR 
permit programs (Oklahoma, Georgia, and Texas). Moreover, in RCRA 
section 4005(d)(1) Congress established specific standards and mandated 
the process for EPA to determine that state requirements should operate 
in lieu of the federal. Under those provisions, a state can apply to 
obtain authorization from EPA to operate its program (either in whole 
or in part) in lieu of the federal requirement by demonstrating that 
either of the standards in RCRA section 4005(d)(1)(B) has been met. 
Relying on that congressionally mandated process, rather than this 
rulemaking, is the appropriate route to address the commenters' 
concerns about duplication between federal and state requirements.
    EPA acknowledges that since the 2015 CCR Rule and the USWAG 
decision some units have closed or have begun to close in accordance 
with state permits. The Agency is also aware of units that closed on 
their own initiative in response to the D.C. Circuit's ruling. In 
response to the ANPRM, EPA received information that since October 19, 
2015, 22 surface impoundments at inactive facilities have closed by 
removal, and 27 surface impoundments have closed with waste in place, 
either with oversight from a state agency or on their own initiative in 
response to the USWAG decision. A number of commenters claimed that 
their units are heavily vegetated or developed and that reopening or 
other removal/remediation activities may disrupt current use of the 
land. It may well be that some old units are heavily vegetated. 
However, no commenter submitted any data or analysis to demonstrate 
that, over the long term, removal or remediation activities would be 
more detrimental to health and the environment than either cleaning up 
the contaminated groundwater or taking measures to prevent the legacy 
CCR surface impoundment from contaminating groundwater.
    Moreover, the fact that some impoundments have become heavily 
vegetated or redeveloped does not resolve the risks these unlined 
legacy CCR surface impoundments continue to pose. At a minimum, the 
record shows that significant numbers of CCR surface impoundments were 
constructed such that the base of the unit intersects with groundwater, 
and that many inactive, or even ``closed,'' impoundments continue to 
impound water below the water table (i.e., contain liquid). The risks 
associated with such closures can be substantial. See Unit IV.B.1.b of 
this preamble for more information. Consequently, based on the current 
record, EPA could not support an exemption for units that still contain 
both liquid and CCR even if the closure or remediation may disrupt the 
current use of the land.
c. Inactive Facility
    Consistent with USWAG, EPA is proposing to regulate all inactive 
CCR surface impoundments at inactive utilities. To support this 
decision, EPA is proposing to define an inactive utility (or inactive 
facility) as one that ceased producing electricity prior to October 19, 
2015. This date is the effective date of the 2015 CCR Rule. This is 
also the same date currently used in the regulation to define ``active 
facility,'' and that EPA originally used to define the exempted units. 
Use of this date would mean that the same universe of units that were 
subject to the original exemption would be regulated. This is 
consistent with the Court's vacatur, as vacatur is intended to restore 
the status quo ante, as though the vacated provision never existed.
    This definition is important to identify which facilities have 
legacy CCR surface impoundments and therefore are subject to these 
proposed regulations. EPA is relying on the existing rulemaking record 
and provisions in Sec.  257.50(b) to draw conclusions about the 
production of power such that an inactive facility contains ``units 
that dispose or otherwise engage in solid waste management of CCR 
generated from the combustion of coal at electric utilities and 
independent power producers,'' and from Sec.  257.50(c), which says 
``electric utilities or independent power producers, regardless of the 
fuel currently used at the facility to produce electricity.'' EPA is 
also relying on the existing definition of ``facility'' which means 
``all contiguous land, and structures, other appurtenances, and 
improvements on the land, used for treating, storing, disposing, or 
otherwise conducting solid waste management of CCR. A facility may 
consist of several treatment, storage, or disposal operational units 
(e.g., one or more landfills, surface impoundments, or combinations of 
them).''
    Ownership and the ability to identify those responsible for 
complying with these regulations is a key consideration for the 
proposed definition of an inactive facility. EPA analyzed the list of 
inactive CCR facilities provided in the ANPRM comments and conducted 
additional research to determine the owner of those facilities. To 
identify the owners of legacy CCR surface impoundments, EPA conducted a 
two-tiered research process. First, EPA conducted a general search that 
included desktop research, with a focus on news articles and trade 
publications regarding plant closures and ownership transfers, to 
identify the most recent identified owner of each former plant. Where 
possible, EPA confirmed the findings with utility websites, which often 
contain information on retired or converted plants, and often have 
corporate timelines that identify transfer of properties to other 
parties. In addition, where possible, when EPA identified an owner, the 
Agency attempted to confirm that the property or plant was listed on 
the owner's website. If information could not be confirmed, EPA 
continued researching until all other entities that could potentially 
currently own the plant could be ruled out. Second, EPA ran these 
identified owners through the Dun & Bradstreet Hoover's database to 
identify the ultimate corporate parent of the identified owner. The 156 
legacy CCR surface impoundments on the list are associated with 37 
different unique corporate parents. Of the 156, the vast majority, 126, 
are owned by a set of 23 companies the Agency knows own facilities 
regulated by the CCR regulations. The remaining 30 units are owned by 
14 different companies, with each company generally having just one 
location/site with legacy CCR surface impoundments (with one exception, 
that owns two sites). Therefore, it appears that most of the inactive 
facilities are owned by companies that are already regulated by the CCR 
regulations. Some of them are owned by a company that is not currently 
regulated by the CCR regulations, but the company has at least one 
facility with potential legacy CCR surface impoundments. EPA has not 
identified any facilities where the owner cannot be determined.
    In the ANPRM, EPA solicited comments about innocent owners of 
inactive facilities, but several commenters said that unlike the 
Comprehensive Environmental Response, Compensation, and Liability Act 
(CERCLA), RCRA does not contain an ``innocent owner'' concept, and 
there is therefore no statutory basis for uniformly excluding these 
owners from any RCRA regulations applicable to

[[Page 31995]]

legacy CCR surface impoundments. The same commenter said the owner 
should be the owner at the time of rule promulgation and that owner 
would be in a position to make decisions and act in response to new 
regulatory requirements applicable to the legacy CCR surface 
impoundments. Based on EPA's analysis of inactive facility ownership, 
EPA has no factual basis to establish an innocent owner provision and 
therefore is not proposing one.
    A commenter suggested that EPA should use the phrase ``permanently 
ceased generating,'' because plants can exist in various stages of 
generation, including seasonal mothball status, depending on the market 
conditions and the needs of the independent system operators. EPA 
disagrees that this is necessary or appropriate, as any facility that 
generates power after October 19, 2015, is considered an ``active 
facility,'' that is covered under the existing regulations. See, 40 CFR 
257.53 (defining Active facility). Under Sec.  257.50(c), the 
regulations apply to ``inactive CCR surface impoundments at active 
electric utilities or independent power producers, regardless of the 
fuel currently used at the facility to produce electricity.'' 40 CFR 
257.50(c).
    The question has been raised whether the phrase ``regardless of the 
fuel currently used to produce electricity'' in Sec.  257.50(c) 
indicates that EPA meant to limit the rule to facilities that combust 
fossil fuels; but the provision does not state or even imply that 
limitation. The definition of an active facility does not include any 
limitation related to how the facility generates electricity, including 
fuel use. Nor does the clause, ``regardless of the fuel currently used 
to produce electricity'' in Sec.  257.50(c) add a fuel use limitation 
into that definition, or otherwise create a fuel use limitation in the 
scope of the rule. The plain language of the clause states the 
opposite; that coverage applies without regard to the fuel used to 
produce electricity. Or in other words, without regard to the type of 
fuel used or indeed whether any fuel is used to produce electricity. 
Nevertheless, to avoid any further confusion, EPA is proposing to amend 
the provision to specify that the subpart also applies to inactive CCR 
surface impoundments at active electric utilities or independent power 
producers, regardless of how electricity is currently being produced at 
the facility.
    Finally, EPA requested comment as to whether the Agency's 
regulation of inactive CCR surface impoundments should be limited to 
only units at former power plants that sold electric power to the grid 
or whether it should also reach units at former power plants that 
provided power to a single site or facility. In response, some 
commenters said that EPA should regulate all inactive impoundments 
without regard to whether those impoundments are located at power 
plants that once sold electric power to the grid or supplied it only to 
a single site or facility. They said it is not the location of the 
impoundment, but rather the presence of coal ash, that controls. Other 
commenters said this could also prove to be a thorny factual issue, as, 
in many cases, the same power plant might have served a single site or 
facility for some period of time as well as served the grid at other 
times.
    For the same reasons that EPA did not include CCR generated by non-
utility boilers in the 2015 CCR Rule, EPA is not proposing to regulate 
units at former power plants that provided power to a single site or 
facility. See, 80 FR 21340. EPA lacks critical data about such 
facilities needed to determine whether and how to regulate such 
facilities. These facilities are primarily engaged in business 
activities, such as agriculture, mining, manufacturing, transportation, 
and education. These industries, and the manufacturing industries in 
particular, generate other types of wastes that are often mixed or co-
managed with the CCR at least at some facilities. As a result, the 
chemical composition of the co-managed waste is likely to be 
fundamentally different from the chemical composition of CCR generated 
by electric utilities or independent power producers. EPA requests 
comment on the likely chemical composition of other types of wastes 
generated by these industries that were co-managed with any CCR 
generated at such facilities. Insufficient information is also 
available on such facilities to determine whether a regulatory 
flexibility analysis will be required under the Regulatory Flexibility 
Act, and to conduct one if it is necessary. EPA therefore requests 
comment on whether the Agency should continue to pursue this issue by 
seeking to obtain the information necessary to determine whether 
regulation of such facilities is warranted.
d. Conclusions Related to Scope of Coverage
    After considering all of this information, EPA is proposing to 
define a legacy CCR surface impoundment as: A surface impoundment that 
is located at a power plant that ceased generating power prior to 
October 19, 2015, and the surface impoundment contained both CCR and 
liquids on or after October 19, 2015. EPA considers this definition to 
be the most protective of human health and the environment for the 
reasons provided herein.
    Alternatively, EPA solicits comments on defining a ``legacy CCR 
surface impoundment'' as: A CCR surface impoundment at a power plant 
that ceased generating power prior to October 19, 2015, and the surface 
impoundment contains both CCR and liquids on or after the effective 
date of the legacy CCR surface impoundment final rule.
2. Applicable Requirements for Legacy CCR Surface Impoundments and 
Compliance Deadlines
    This Unit of the preamble first provides a general overview of how 
EPA determined the applicable requirements and compliance deadlines for 
legacy CCR surface impoundments. Then, EPA will walk through each of 
the existing requirements for CCR surface impoundments and explain (1) 
Why EPA is proposing to apply them (or not) to legacy CCR surface 
impoundments, and (2) The rationale for the compliance deadline EPA is 
proposing for each requirement.
a. General Overview
i. Applicable Requirements
    Based on the record compiled for the 2015 CCR Rule, EPA concluded 
that ``there is little difference between the potential risks of an 
active and inactive surface impoundment; both can leak into 
groundwater, and both are subject to structural failures that release 
the wastes into the environment, including catastrophic failures 
leading to massive releases that threaten both human health and the 
environment.'' (80 FR 21343). As discussed in Unit III.B of this 
preamble, the D.C. Circuit concurred, and on that basis, vacated the 
exemption for legacy CCR surface impoundments. See, USWAG at 901 F.3d 
at 434. EPA received no information in response to the ANPRM that would 
support a conclusion that legacy CCR surface impoundments present fewer 
risks than other inactive CCR impoundments. Based on this record and on 
the specificity of the D.C. Circuit's findings in USWAG, EPA considers 
that it has limited discretion to establish requirements for legacy CCR 
surface impoundments that are significantly different than those 
currently applicable to inactive CCR impoundments. Accordingly, EPA is 
proposing that, in most cases the existing requirements in 40 CFR part 
257, subpart D applicable to inactive CCR surface impoundments would 
apply to legacy CCR surface

[[Page 31996]]

impoundments. EPA is proposing to make one revision to the existing 
groundwater monitoring requirements. In addition, EPA is proposing to 
establish two new requirements specific to legacy CCR surface 
impoundments: a reporting requirement and a new security requirement to 
restrict public access to these sites. Finally, EPA is proposing that 
legacy CCR surface impoundments would not be subject to either the 
location restrictions at Sec. Sec.  257.60 through 257.64, or the liner 
design criteria at Sec.  257.71. EPA is proposing to exclude these 
requirements because EPA believes they will not be necessary if EPA 
takes final action on the proposed requirement that all legacy CCR 
surface impoundments initiate closure no later than 12 months after the 
effective date of the final rule.
    Some commenters on the ANPRM said that all provisions currently 
required for CCR surface impoundments at active power plants (or those 
that were operating as of the effective date of the rule), are just as 
necessary--if not more so--at legacy CCR surface impoundments to ensure 
satisfaction of the RCRA section 4004(a) protectiveness standard. Other 
commenters said the only applicable requirements should be groundwater 
monitoring, closure, post-closure care, and related recordkeeping 
requirements. Several of these commenters also said that the 2015 CCR 
rulemaking record is not directly applicable to the universe of units 
that are located at inactive power plants and still contain CCR and 
liquids. They said the 2014 CCR Risk Assessment used to develop the 
2015 CCR Rule was limited to current disposal practices and did not 
consider units that had stopped receiving waste or historically 
disposed of CCR by facilities that no longer operate. According to 
these commenters, the Agency must first accurately identify the 
universe of legacy CCR surface impoundments, the specific 
characteristics of risk for those impoundments, and then analyze 
whether other authorities are sufficient to address any risk from these 
legacy CCR surface impoundments.
    Finally, some commenters requested that EPA include a mechanism for 
legacy CCR surface impoundment owner(s) and/or operator(s) to 
demonstrate that, in such cases, additional CCR requirements would be 
unnecessary. The commenters stated that this would be similar to the 
case-by-case determinations established under the Holistic Approach to 
Closure Parts A and B final rules (85 FR 53516 and 85 FR 72506) that 
provided a mechanism for the Agency to issue variances for plants that 
could successfully make the required demonstration.
ii. Compliance Deadlines
    EPA is proposing to establish new compliance dates for legacy CCR 
surface impoundments. The compliance deadlines in the 2015 CCR Rule 
were generally based on the amount of time determined to be necessary 
to implement the requirements. To determine what was feasible, EPA 
accounted for the fact that some of the new requirements involved 
numerous activities, many of which must occur sequentially (e.g., the 
groundwater monitoring requirements in Sec. Sec.  257.90 through 
257.95), as well as concerns about shortages of contractor and lab 
resources resulting from the fact that those numerous facilities would 
need to come into compliance at the same time. EPA also accounted for 
other Agency rulemakings that could have affected the owners or 
operators of CCR units, namely the 2015 Effluent Limitation Guidelines 
(ELG) and Standards for the Steam Electric Power Generating Point 
Source Category and the Carbon Pollution Commission Guidelines for 
Existing Stationary Sources: Electric Utility Generating Units. In 
establishing the proposed deadlines for legacy CCR surface 
impoundments, EPA adopted the same approach, and is proposing deadlines 
based on the amount of time determined to be necessary to implement the 
requirements. But some of the factors considered in the 2015 rulemaking 
are not relevant for legacy CCR surface impoundments; for example, 
there is no longer a need to coordinate with the ELG compliance 
deadlines. In addition, most facilities are already familiar with these 
requirements as they have already implemented them for other units at 
their active sites, so the timeframes need not account for the time 
that would be needed for a facility to understand the regulations and 
develop strategies for compliance. Finally, there will be fewer 
facilities and units that will need to come into compliance, and EPA no 
longer has concerns about shortages of contractors and lab resources. 
Consequently, EPA is generally proposing expedited timeframes for 
legacy CCR surface impoundments to comply with the regulations, based 
on the shortest average amount of time needed to complete the 
activities involved in meeting the requirements. Overall, comments 
submitted in response to the ANPRM acknowledged these differences and 
most supported the establishment of shorter deadlines than were 
established in the 2015 CCR Rule.
    Note that all deadlines herein are framed by reference to the 
effective date of the rule and have been proposed based on an effective 
date that is six months from publication of the final rule. The Agency 
has included a document in the docket \13\ for this rule that 
summarizes the proposed compliance deadlines. EPA requests comment on 
the compliance deadlines and the feasibility to meet the proposed 
compliance timeframes for legacy CCR surface impoundments.
---------------------------------------------------------------------------

    \13\ This information can be found in the document titled 
``Proposed Compliance Deadlines for Legacy CCR Surface Impoundments 
and CCR Management Units'' in the docket for this action.

  Table 1--Proposed Compliance Timeframes for Legacy CCR Surface Impoundments in Months After Effective Date of
                                                 the Final Rule
----------------------------------------------------------------------------------------------------------------
                                        Description of        Proposed deadline  (months
    40 CFR part 257, subpart D        requirement to be      after  effective date of the           Notes
            requirement                   completed                  final rule)
----------------------------------------------------------------------------------------------------------------
Applicability Documentation (Sec.   Applicability          0..............................  Prerequisite
  257.100).                          Documentation for                                       requirements:
                                     the legacy CCR                                          Establish CCR
                                     surface impoundment.                                    website.
                                                                                            Subsequent
                                                                                             requirements:
                                                                                             History of
                                                                                             construction;
                                                                                             Initial structural
                                                                                             stability
                                                                                             assessment; Initial
                                                                                             safety factor
                                                                                             assessment.
Design Criteria (Sec.   257.73)...  Install permanent      0..............................
                                     marker.
Site Security (Sec.                 Implement site         0..............................
 257.100(f)(3)(iii)).                security measures.

[[Page 31997]]

 
Operating Criteria (Sec.   257.80)  Prepare fugitive dust  0..............................  Subsequent
                                     control plan.                                           requirements:
                                                                                             Initial annual
                                                                                             fugitive dust
                                                                                             report.
Operating Criteria (Sec.   257,80,  Initiate weekly        0..............................  Subsequent
 257.82, 257.83).                    inspections of the                                      requirements:
                                     CCR unit.                                               Initial annual
                                                                                             inspection of the
                                                                                             CCR unit.
Operating Criteria (Sec.   257,80,  Initiate monthly       0..............................  Subsequent
 257.82, 257.83).                    monitoring of CCR                                       requirements:
                                     unit instrumentation.                                   Initial annual
                                                                                             inspection of the
                                                                                             CCR unit.
Internet Posting (Sec.   257.107).  Establish CCR website  0..............................  Subsequent
                                                                                             requirements:
                                                                                             Applicability
                                                                                             report; all
                                                                                             recordkeeping.
Design Criteria (Sec.   257.73)...  Compile a history of   3..............................  Prerequisite
                                     construction.                                           requirements:
                                                                                             Applicability
                                                                                             report.
                                                                                            Subsequent
                                                                                             requirements:
                                                                                             Hazard potential
                                                                                             classification;
                                                                                             Emergency Action
                                                                                             Plan; Initial
                                                                                             hazard
                                                                                             classification
                                                                                             assessment; Initial
                                                                                             structural
                                                                                             stability
                                                                                             assessment; Initial
                                                                                             safety factor
                                                                                             assessment; Initial
                                                                                             annual inspection;
                                                                                             Groundwater
                                                                                             monitoring system.
Design Criteria (Sec.   257.73)...  Complete initial       3..............................  Prerequisite
                                     hazard potential                                        requirements:
                                     classification                                          Applicability
                                     assessment.                                             report; History of
                                                                                             construction.
                                                                                            Subsequent
                                                                                             requirements:
                                                                                             Emergency Action
                                                                                             Plan.
Design Criteria (Sec.   257.73)...  Complete initial       3..............................  Prerequisite
                                     structural stability                                    requirements:
                                     assessment.                                             Applicability
                                                                                             report; History of
                                                                                             construction.
                                                                                            Subsequent
                                                                                             requirements:
                                                                                             Emergency Action
                                                                                             Plan.
Design Criteria (Sec.   257.73)...  Complete initial       3..............................  Prerequisite
                                     safety factor                                           requirements:
                                     assessment.                                             Applicability
                                                                                             report; History of
                                                                                             construction.
                                                                                            Subsequent
                                                                                             requirements:
                                                                                             Emergency Action
                                                                                             Plan.
Operating Criteria (Sec.   257,80,  Complete the initial   3..............................  Prerequisite
 257.82, 257.83).                    annual inspection of                                    requirements:
                                     the CCR unit.                                           History of
                                                                                             construction;
                                                                                             Weekly inspections
                                                                                             of the CCR unit;
                                                                                             Monthly monitoring
                                                                                             of CCR unit
                                                                                             instrumentation.
GWMCA (Sec.   257.91).............  Install the            6..............................  Prerequisite
                                     groundwater                                             requirements:
                                     monitoring system.                                      Applicability
                                                                                             report; History of
                                                                                             construction.
                                                                                            Subsequent
                                                                                             requirements:
                                                                                             Groundwater
                                                                                             sampling and
                                                                                             analysis program;
                                                                                             Initiate detection
                                                                                             and assessment
                                                                                             monitoring; Annual
                                                                                             GWMCA report;
                                                                                             Written closure
                                                                                             plan; Initiate
                                                                                             closure.
GWMCA (Sec.   257.93).............  Develop the            6..............................  Prerequisite
                                     groundwater sampling                                    requirements:
                                     and analysis program.                                   Install the
                                                                                             groundwater
                                                                                             monitoring system.
                                                                                            Subsequent
                                                                                             requirements:
                                                                                             Initiate detection
                                                                                             monitoring and
                                                                                             assessment
                                                                                             monitoring.
GWMCA (Sec.   257.90(e))..........  Annual GWMCA report..  January 31 of the year           Prerequisite
                                                            following GWM system install.    requirements:
                                                                                             Groundwater
                                                                                             monitoring system;
                                                                                             Groundwater
                                                                                             sampling and
                                                                                             analysis plan.
Design Criteria (Sec.   257.73)...  Prepare Emergency      9..............................  Prerequisite
                                     Action Plan.                                            requirements:
                                                                                             History of
                                                                                             construction;
                                                                                             Hazard potential
                                                                                             classification;
                                                                                             Initial structural
                                                                                             stability
                                                                                             assessment; Initial
                                                                                             safety factor
                                                                                             assessment.
Operating Criteria (Sec.   257.82)  Prepare initial        9..............................  Prerequisite
                                     inflow design flood                                     requirements:
                                     control system plan.                                    History of
                                                                                             construction;
                                                                                             Hazard potential
                                                                                             classification.
Operating Criteria (Sec.   257.80)  Prepare initial        12.............................  Prerequisite
                                     annual fugitive dust                                    requirements:
                                     report.                                                 Fugitive dust plan.
Closure (Sec.  Sec.   257.100-      Prepare written        12.............................  Subsequent
 257.101).                           closure plan.                                           requirements:
                                                                                             Initiate closure.
Post-Closure Care (Sec.   257.104)  Prepare written post-  12.............................  Prerequisite
                                     closure care plan.                                      requirements:
                                                                                             Written closure
                                                                                             plan.
Closure and Post-Closure Care       Initiate closure.....  12.............................  Prerequisite
 (Sec.   257.101).                                                                           requirements:
                                                                                             Written closure
                                                                                             plan.
GWMCA (Sec.  Sec.   257.90-257.95)  Initiate the           24.............................  Prerequisite
                                     detection monitoring                                    requirements:
                                     and assessment                                          Groundwater
                                     monitoring. Begin                                       monitoring system;
                                     evaluating the                                          Groundwater
                                     groundwater                                             sampling and
                                     monitoring data for                                     analysis plan.
                                     SSI over background
                                     levels and SSL over
                                     GWPS.
----------------------------------------------------------------------------------------------------------------

[[Page 31998]]

b. New Requirements Specific to Legacy CCR Surface Impoundments
i. Legacy CCR Surface Impoundment Applicability Documentation
    EPA is proposing to require the owner and operator of a legacy CCR 
surface impoundment to prepare an applicability documentation for any 
legacy CCR surface impoundment at that facility no later than the 
effective date of the final rule. This requirement would apply to all 
legacy CCR surface impoundments, including incised impoundments and 
impoundments that do not meet the height and storage volume cutoffs 
specified in Sec.  257.73(b). See, proposed regulatory text at Sec.  
257.100(f)(1)(i). EPA is proposing that this applicability 
documentation would include information to identify the unit, delineate 
the unit boundaries, include a figure of the facility and where the 
unit is located at the facility, the size of the unit, its proximity to 
surface water bodies, and the current site conditions. For impoundments 
that are incised or for those not meeting the height and storage volume 
thresholds specified in Sec.  257.73(b), the applicability report must 
document these conditions so that stakeholders can understand what 
structural integrity requirements will apply to the legacy CCR surface 
impoundment. EPA is also proposing that the applicability report 
include the facility address, latitude and longitude, and contact 
information of the owner and/or operator of the legacy CCR surface 
impoundment with their phone number and email address. EPA is also 
proposing that the owner or operator of the legacy CCR surface 
impoundment notify the Agency of the establishment of the facility's 
CCR website and the applicability of the rule, using the procedures 
currently in Sec.  257.107(a) via the ``contact us'' form on EPA's CCR 
website.
ii. Site Security for Legacy CCR Surface Impoundments
    Active facilities generally have guards and fencing to control 
access to the facility, but inactive CCR facilities may not have such 
security controls in place at the facility. To minimize that risk, EPA 
is proposing that owners and operators establish security controls to 
restrict access to legacy CCR surface impoundments. The proposed 
security requirements are written in terms of a performance standard, 
as opposed to a prescriptive set of technical standards, such as 
specific signage, barriers and fencing, or surveillance techniques. EPA 
chose this approach because it would allow the owner or operator to 
identify the most appropriate means for providing site security for the 
impoundment based on site-specific circumstances.
    Some commenters on the ANPRM agreed that such requirements are 
necessary because legacy CCR impoundments are located at inactive power 
plants, unlike impoundments at operating power plants, they almost 
certainly lack the oversight and protection afforded by significant 
numbers of on-site personnel. Consequently, the integrity of 
impoundments and berms and the safety of nearby residents depend on 
robust security measures to ensure that people are not--whether 
intentionally or unknowingly--entering the site and taking actions 
(such as ATV driving, dirt biking, or similar activities) that endanger 
the integrity of the impoundment or expose trespassers to health risks.
    The proposed site security performance standard would require the 
owner or operator to prevent the unknowing entry of people onto the 
legacy CCR surface impoundment and to minimize the potential for the 
unauthorized entry of people or livestock onto the impoundment. See 
proposed regulatory text in Sec.  257.100(f)(3)(iii). The Agency 
generally modeled the proposed requirements on existing regulations 
that apply to interim status hazardous waste surface impoundments, 
which are codified at Sec.  265.14(a). EPA recognizes that some 
facilities may have facility-wide access controls in place, and in this 
case, the facility-wide controls would satisfy the proposed requirement 
to limit public access to the legacy CCR surface impoundment. The 
Agency is proposing to require the facility to restrict access to the 
area containing the legacy CCR surface impoundment no later than the 
effective date of the final rule. See, proposed regulatory text at 
Sec.  257.100(f)(3)(iii).
iii. Certification of Closure by Removal for Legacy CCR Surface 
Impoundments
    As discussed in Unit IV.A.1.b.ii of this preamble, where a legacy 
CCR surface impoundment has completed closure of the CCR unit by 
removal of waste in accordance with the performance standards in Sec.  
257.102(c) prior to the effective date of the final rule, EPA is 
proposing that the owner and operator of an inactive facility post 
documentation that they have met the existing standard for closure by 
removal in Sec.  257.102(c) on their CCR website. If such a 
demonstration cannot be made, the CCR surface impoundment would be 
regulated as a legacy CCR surface impoundment. EPA is proposing to 
require that the closure certification be certified by a qualified 
professional engineer (P.E.). EPA is proposing to require certification 
by a qualified professional engineer even though the Agency now has 
authority to enforce the part 257 regulations. This is because the 
certification is not intended as a substitute for EPA's oversight, but 
as a supplement to ensure that the regulated community properly 
understands and implements the regulations. As EPA explained in 2015, 
the purpose of requiring certification was to ensure that qualified 
individuals verify that the technical provisions of the rule have been 
properly applied and met, not to delegate regulatory oversight to the 
engineer, or to serve as a shield against judicial enforcement. See 80 
FR 21335. Consistent with the original 2015 requirements, the 
performance standards that EPA is proposing to establish are 
independent requirements and would remain enforceable regardless of 
whether a P.E. certification has been obtained.
    EPA is proposing to require that the certified demonstration be 
completed and posted on the facility website no later than the 
effective date of the final rule. See proposed regulatory text at Sec.  
257.100(f)(1)(ii). Because the closure of the unit will have been 
already completed, the information on which to base the demonstration 
should be readily available. Consequently, EPA believes that requiring 
completion of this requirement, if applicable, by the effective date of 
the final rule provides sufficient time for such a task.
c. Location Restrictions and Liner Design Criteria
    The CCR regulations require existing CCR surface impoundments that 
cannot demonstrate compliance with the location restrictions for 
placement of CCR above the uppermost aquifer, in wetlands, within fault 
areas, in seismic impact zones, or in unstable areas (specified in 
Sec. Sec.  257.60 through 257.64) to cease receipt of waste and 
retrofit or close. The purpose of these requirements is largely to 
ensure that units located in particularly problematic areas cease 
operation. By definition, legacy CCR surface impoundments are not 
operating, and because it appears that all legacy CCR surface 
impoundments are unlined and will therefore be required to close, EPA 
believes that requiring compliance with the location restrictions would 
be largely redundant. Commenters on the ANPRM largely supported not 
requiring location restrictions or liner demonstrations on the grounds 
that location restrictions and operating and

[[Page 31999]]

design criteria are not relevant to this class of units, as these 
requirements primarily sought to ensure active units operated safely. 
Other commenters raised concern that requiring compliance with one or 
more location restrictions would provide information that would be 
``critical'' to designing unit closure and any necessary corrective 
action. EPA agrees that this information would be useful but believes 
the same information will be captured by compliance with the history of 
construction requirement, the closure plan, or in the development of 
the groundwater monitoring system.
    EPA is also proposing that the requirement to document whether the 
impoundment was constructed with a composite liner or alternative 
composite liner under Sec.  257.71(a)(1) is not warranted for legacy 
CCR surface impoundments. The original purpose of this provision was to 
determine whether the unit was unlined, and consequently subject to 
closure. However, the available information indicates that legacy CCR 
surface impoundments were largely constructed well before composite 
liners systems were typically installed. For this reason, EPA expects 
legacy CCR surface impoundment to be unlined and, therefore, EPA is 
proposing to require all legacy CCR surface impoundments to close. As a 
consequence, EPA believes that requiring facilities to compile the 
information required by Sec.  257.71(a)(1) would not provide useful 
information or otherwise be necessary.
d. Design Criteria for Structural Integrity for Legacy CCR Surface 
Impoundments
    To help prevent damages associated with structural failures of CCR 
surface impoundments, existing surface impoundments must meet specified 
structural integrity criteria in Sec.  257.73 as part of the design 
criteria. EPA is proposing that all existing structural integrity 
requirements be applicable to legacy CCR surface impoundments without 
revision.
i. Installation of a Permanent Marker for Legacy CCR Surface 
Impoundments
    Consistent with the existing requirements for CCR surface 
impoundments, EPA is proposing that owners or operators of legacy CCR 
surface impoundments, except for ``incised CCR surface impoundments'' 
as defined in Sec.  257.53, comply with Sec.  257.73(a)(1), which 
requires the placement of a permanent identification marker, at least 
six feet high on or immediately adjacent to the CCR unit with the name 
associated with the CCR unit and the name of the owner or operator. 
See, proposed regulatory text at Sec.  257.100(f)(2)(i).
    EPA is proposing that placement of the permanent marker must be 
completed by the owner or operator of the legacy CCR surface 
impoundment by the effective date of the final rule. By comparison, 
installation of a permanent marker was required two months after the 
effective date of the 2015 CCR Rule. The proposed deadline is expedited 
for the reasons described in Unit IV.A.2.a.ii of this preamble and 
accounts for sufficient time for survey work, and review of records in 
facility deeds or other records.
ii. History of Construction for the Legacy CCR Surface Impoundments
    Under the existing regulations, CCR surface impoundments that 
either have: (1) A height of five feet or more and a storage volume of 
20 acre-feet or more; or (2) Have a height of 20 feet or more, must 
document the design and construction of the CCR surface impoundment. 40 
CFR 257.73(b) and (c). See also 80 FR 21379-21380, April 17, 2015. EPA 
is proposing that owners or operators of legacy CCR surface 
impoundments that meet this size threshold would be required to comply 
with the existing requirements to compile the construction history of 
the legacy CCR surface impoundment. See proposed regulatory text in 
Sec.  257.100(f)(2)(ii).
    Some commenters on the ANPRM agreed that the history of 
construction is critical to an evaluation of the long-term stability of 
legacy CCR surface impoundments, which must be considered to determine 
if the closure performance standards for closure in place can be met at 
the impoundment and whether a given corrective action meets the 
requirement to select a safe, protective remedy. The history of 
construction is also critical in the event of any failure of the 
impoundment: emergency response personnel must have access to that 
information to determine how to halt further failure, and further 
release of CCR, as quickly as possible.
    For legacy CCR surface impoundments, EPA acknowledges that much of 
the construction history of the surface impoundment may be unknown or 
lost to time. The Agency conducted assessments of impoundments across 
the country starting in 2009 (herein referred to as 2009-2014 
Assessment Program). For information about these assessments and how 
the results impacted the 2015 CCR Rule, see 80 FR 21313-21318 (April 
17, 2015). The results from the 2009-2014 Assessment Program confirmed 
that many owners or operators of CCR units did not possess 
documentation on the construction history or operation of the CCR unit. 
80 FR 21380. Information regarding construction materials, expansions 
or contractions of units, operational history, and history of events 
was frequently difficult for the owners or operators to obtain. 
Therefore, consistent with the existing regulations, the owner or 
operator would only need to provide information on the history of 
construction to the extent that such information is reasonably and 
readily available.
    To complete the history of construction report, typically, the 
owner and operator first enlist a contractor to generate the history of 
construction report. Contracting typically involves the owner and 
operator issuing a request for proposal, contractors responding to the 
request, and the owner and operator evaluating the bids and selecting a 
contractor (estimate 1-2 weeks). Following selection and onboarding of 
a contractor, a data inventory, compilation, and review of existing 
documents is completed by the owner and operator and contractor to meet 
the requirements in Sec.  257.73(c)(1)(i) through (xi) (estimate 4-6 
weeks). Examples of documents compiled may include the CCR unit's 
design drawings and construction documents, such as construction 
reports, quality assurance, as-built records, and historic boring log 
reviews (e.g., subsurface investigation used for original CCR unit 
design, post-construction subsurface investigations, geotechnical 
studies). Data from external sources may also be needed such as the 
U.S. Geological Survey (USGS) 7.5-minute or 15-minute topographic 
quadrangle maps (Sec.  257.73(c)(1)(ii)) or National Hydrography 
Datasets (Sec.  257.73(c)(1)(iv)). The compiled data must then be 
reviewed, analyzed, and documented in reports (estimate 3-4 weeks). 
Examples of analyses may include maximum CCR depths, area-capacity 
curves, spillway capacities, and the maximum pool surface elevation 
following peak discharge from the inflow design flood. This estimate 
assumes that no new extensive analyses are needed, and that all 
necessary information can be derived from existing reports (e.g., 
hydraulic and hydrologic reports). If new analyses are needed (e.g., 
maximum CCR depth), they are assumed to be minor with data inputs for 
performing these analyses existing and readily available such as field 
surveys (e.g., historic site preparation surveys, post-construction/as-
built surveys, periodic surveys,

[[Page 32000]]

bathymetric surveys). Based on these assumptions, the time required to 
generate a history of construction report is 8-12 weeks or 2-3 months. 
Therefore, EPA is proposing to require the history of construction 
report to be compiled no later than 3 months after the effective date 
of the final rule.
    Expediting this timeframe compared to the 2015 CCR Rule timeframe 
is important for the reasons described above in Unit IV.A.2.a.ii of 
this preamble and because several additional requirements depend on the 
information that would be obtained by compliance with these 
requirements. For example, available geologic subsurface information 
from history of construction is typically necessary to determine the 
number, spacing and location of monitoring wells for the installation 
of a groundwater monitoring system that meets the criteria of Sec.  
257.91. Another example is that Sec.  257.73(c)(1)(xi) requires 
reporting any record or knowledge of structural instability of the CCR 
unit; this information is also needed for the initial and periodic 
structural stability assessments required under Sec.  257.73(d).
iii. Initial Hazard Potential Classification for Legacy CCR Surface 
Impoundments
    Consistent with the existing regulations, EPA is proposing that 
owners or operators of legacy CCR surface impoundments, except for 
incised CCR surface impoundments as defined in Sec.  257.53, must 
complete the initial periodic hazard potential classification 
assessment required under Sec.  257.73(a)(2). See, proposed regulatory 
text at Sec.  257.100(f)(2)(iii).
    Hazard potential classification assessments require activities that 
can be summarized as data/documentation review, a site visit, and 
report generation. As stated above, acquiring a contractor may take 1-2 
weeks. The contractor would then perform a site visit and review 
available hazard documents such as existing state or federal dam hazard 
potential classification documents or any previous structural stability 
or safety factor documentation. The contractor then generates a P.E.-
certified report stating the hazard classification determination and 
basis for the findings. The site visit is estimated to take 1 week. The 
data/documentation review and report generation are expected to take a 
total of 4-6 weeks. Based on these estimates, the total time needed to 
conduct the initial hazard potential classification assessment is 6-9 
weeks. Accordingly, EPA is proposing the initial hazard potential 
classification assessment be due no later than 3 months after the 
effective date of the final rule. The proposed deadline provides 
sufficient time to complete the activities necessary to satisfy this 
requirement, while allowing time (3-6 six weeks) for reasonable delays, 
such as weather delaying a site visit or difficulty obtaining pertinent 
documentation. This timeframe is expedited from the deadline in the 
2015 CCR Rule by 9 months for the reasons described above in Unit 
IV.A.2.a.ii of this preamble.
iv. Initial Structural Stability Assessment and Initial Safety Factor 
Assessment for Legacy CCR Surface Impoundments
    Under the existing regulations, CCR surface impoundments that meet 
the size thresholds in Sec.  257.73(b) and (c), must conduct two 
different types of technical assessments: (1) A structural stability 
assessment; and (2) A safety factor assessment. See 40 CFR 257.73(b), 
(d), (e), and (f). See also 80 FR 21380-21386, April 17, 2015. EPA is 
proposing that owners or operators of legacy CCR surface impoundments 
that meet the same thresholds also comply with the requirements to 
conduct an initial structural stability assessment and an initial 
safety factor assessment. See, proposed regulatory text at Sec.  
257.100(f)(2)(iv).
    Some commenters on the ANPRM said structural stability assessments 
and safety factor assessments must apply to legacy CCR surface 
impoundments since the risks from such units are likely greater at 
legacy CCR surface impoundments, given the age of such units; the 
higher percentage of legacy ponds (as compared to operating ash ponds) 
that were neither designed by, nor built under the supervision of, a 
P.E.; and the higher percentage of legacy CCR surface impoundments 
determined to be in ``poor'' or ``fair'' condition.
    The Agency conducted assessments of impoundments across the country 
starting in 2009 in the 2009-2014 Assessment Program. For information 
about these assessments and how the results impacted the 2015 CCR Rule, 
see 80 FR 21313-21318 (April 17, 2015). EPA analyzed the results of the 
2009-2014 Assessment Program and found that 97 impoundments \14\ 
assessed during the Program are located at inactive CCR facilities. Of 
those impoundments, EPA found that six impoundments are classified as 
high hazard potential, and 41 impoundments are classified as 
significant hazard potential meaning that failure or mis-operation of 
the dam will probably cause loss of human life or can cause economic or 
environmental losses. This further supports EPA's conclusion that these 
requirements are needed for legacy CCR surface impoundments.
---------------------------------------------------------------------------

    \14\ This information can be found in the document titled 
``Potential Legacy CCR Surface Impoundment Universe'' in the docket 
for this action.
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    Activities required to conduct the initial structural stability 
assessment include reviewing historic documents, conducting a site 
investigation (if needed), and generating a P.E.-certified report. 
Typically, owners or operators hire a contractor who is a certified 
P.E., which, as detailed above, may take one to two weeks. The 
contractor would then compile and review historic documents to 
determine if the design, construction, operation, and maintenance of 
the CCR unit are consistent with good engineering practices, which may 
take 2-3 weeks. These documents likely overlap with those already 
compiled for the history of construction and may include the design 
drawings, construction reports, quality assurance documentation, as-
built records, subsurface investigations, geotechnical studies, and 
site inspections. Stability of the CCR unit's embankment and foundation 
may be demonstrated through slope stability analyses. Because slope 
stability analyses are typically required to satisfy safety factor 
assessments, no additional time is considered necessary to satisfy the 
requirements under Sec.  257.73(d). Although site inspections would 
likely already have occurred by the effective date of the final rule 
pursuant to Sec.  257.83(a) or Sec.  257.83(b), it may be necessary for 
the qualified P.E. to perform a site inspection to certify the CCR unit 
meets the requirements as set forth in Sec.  257.73(d). Therefore, 1 
week for the site inspection is factored into the estimated time to 
complete these assessments. Finally, generating a P.E.-certified report 
may take 4-6 weeks. The total estimated time to meet this requirement 
is 8-12 weeks.
    Activities required to complete the initial safety factor 
assessment may include hiring a contractor that is a qualified P.E., 
which may take 1-2 weeks and conducting slope stability analyses of 
critical cross sections, as defined in Sec.  257.73(e)(1). For the 
initial assessment, it is anticipated that no new field work will be 
required to gather this data and that the input parameters required for 
the analysis (e.g., soil geotechnical properties, seasonal high-water 
table) are available in historic documents such as the subsurface 
investigation used for the original CCR unit design, post-construction 
subsurface investigations, and/or geotechnical studies. Compilation and

[[Page 32001]]

review of this data is estimated to take 2-3 weeks, followed by 5-7 
weeks for data analysis and reporting. The total estimated time needed 
to meet requirements for completion of the safety factor assessment is 
8-12 weeks.
    The activities for the initial structural stability and initial 
safety factor assessments can be conducted concurrently and based on 
the estimates above, should take a total of 8-12 weeks (2-3 months). 
Therefore, as stated above, EPA is proposing both the initial 
structural stability assessment and the initial safety factors 
assessments be completed no later than 3 months after the effective 
date of the final rule. These timeframes are expedited by 15 months 
from the 2015 CCR Rule deadline. EPA believes the expedited timeframe 
is important to address the risks posed by legacy CCR surface 
impoundments, as described in this Unit and in Unit IV.A.2.a.ii of this 
preamble.
v. Preparation of an Emergency Action Plan for Legacy CCR Surface 
Impoundments
    Section 257.73(a)(3) requires any CCR surface impoundment that is 
determined by the owner or operator, with the certification by a P.E., 
to be either a high hazard potential or a significant hazard potential 
CCR surface impoundment to prepare and maintain a written Emergency 
Action Plan (EAP). EPA is proposing that the owners or operators of 
legacy CCR surface impoundments that have been identified as having 
either a high hazard potential or a significant hazard potential would 
be required to comply with the same requirements to prepare and 
maintain an EAP that are currently required under Sec.  257.73. See 
proposed regulatory text at Sec.  257.100(f)(2)(v).
    An EAP is a document that identifies potential emergency conditions 
at a CCR surface impoundment and specifies actions to be followed to 
minimize loss of life and property damage. To prepare an EAP, the owner 
or operator must accurately and comprehensively identify potential 
failure modes and at-risk developments. See also 80 FR 21377-21379, 
April 17, 2015. Satisfying EAP requirements is primarily a desktop 
exercise that requires information on site conditions, some analyses, 
and assessments that are proposed to be completed earlier. Typically, 
the owner and operator enlist a contractor to generate the EAP, which, 
as described above may take 1-2 weeks. Once onboard, it is assumed that 
the contractor would review site-specific documents, assessments, and 
analyses that were completed earlier and that may have an impact on 
development of an EAP. These documents and assessments may include the 
history of construction, initial structural stability assessment, 
initial safety factor assessment, initial hazard potential 
classification, hydraulic and hydrologic analyses for inundation maps 
and potential impact areas, and the first annual inspection. Assuming 
all analyses discussed in the preceding sections are completed by the 
proposed deadlines of 3 months after the effective date of the final 
rule, the review of existing documents and assessments is estimated to 
take 4-6 weeks. Additional analyses, such as dam breach analyses or 
inundation evaluations, may be needed to define events or circumstances 
that may represent a safety emergency. If needed, these analyses may 
take 3-6 weeks). The contractor would then prepare the EAP including 
describing procedures to follow in an emergency, gathering emergency 
responder contact information and defining responsible persons, 
assigning responsibilities, and detailing notification procedures. This 
may take 6-8 weeks because the required coordination with community or 
government entities. Based on these assumptions, the time required to 
complete an EAP is 3-6 months. Therefore, EPA is proposing a deadline 
of 9 months after the effective date for this requirement. This 
timeline is sufficient to review previously prepared documents, 
complete additional analyses and prepare the EAP while accounting for 
the 3 months allotted for the prerequisite assessments.
e. Operating Criteria for Legacy CCR Surface Impoundments
    The operating criteria in Sec. Sec.  257.80, 257.82, and 257.84 
include air criteria for all CCR units, hydrologic and hydraulic 
capacity requirements for CCR surface impoundments, and periodic 
inspection requirements for CCR surface impoundments. These criteria 
address the potential risks from the day-to-day operations of CCR units 
and are established to prevent health and environmental impacts from 
CCR units. CCR surface impoundments are subject to hydrologic and 
hydraulic capacity requirements to ensure the unit can safely handle 
flood flows, which will help prevent uncontrolled overtopping of the 
unit or erosion of the materials used to construct the surface 
impoundment. The CCR regulations also require periodic inspections of 
CCR units to identify any appearance of structural weakness or other 
conditions that are not consistent with recognized and generally 
accepted good engineering standards. EPA is proposing that legacy CCR 
surface impoundments comply with these existing requirements without 
revision.
i. Fugitive Dust Control Plan for Legacy CCR Surface Impoundments
    EPA is proposing that owners or operators of legacy CCR surface 
impoundments must complete a fugitive dust control plan. See, proposed 
regulatory text at Sec.  257.100(f)(3)(i). The existing regulations 
require the owner or operator of a CCR unit to adopt measures that will 
effectively minimize CCR from becoming airborne at the facility, 
including CCR fugitive dust originating from CCR units, roads, and 
other CCR management and material handling activities. 40 CFR 
257.80(b). To meet this requirement, the owner or operator of the CCR 
unit must prepare and operate in accordance with a fugitive dust 
control plan. Id. See also 80 FR 21386-21388, April 17, 2015. EPA 
considers that fugitive dust controls are warranted because closure 
activities can produce significant quantities of dust. For the same 
reason, most commenters on the ANPRM agreed that legacy CCR surface 
impoundments should be subject to these requirements.
    The primary activities associated with this requirement are hiring 
a contractor who is a qualified P.E., having the contractor develop a 
plan based on daily operations at the unit and site conditions, and 
certification of the plan by a P.E. Little to no field-based activities 
are required to complete the fugitive dust control plan, so EPA is 
proposing that the owner or operator comply with the existing 
requirements by the effective date of the final rule. This timeline is 
commensurate with the timeline proposed in the 2015 CCR Rule for 
fugitive dust control plans.
ii. Initial Fugitive Dust Control Report for Legacy CCR Surface 
Impoundments
    EPA is proposing to require the initial annual fugitive dust report 
to be due 12 months after the effective date of the final rule. See, 
proposed regulatory text at Sec.  257.100(f)(3)(vi). Consistent with 
the existing regulations, the report must document all actions taken to 
control CCR fugitive dust, a record of all citizen complaints, and a 
summary of any corrective measures taken in the previous year. As this 
report is primarily a summary of owner or operator activities related 
to fugitive dust control and does not require a P.E. certification, the 
report may be completed by the owner or operator without the need for a 
contractor. Therefore, the deadline of 12 months after effective date 
of rule is sufficient for this requirement. This deadline is

[[Page 32002]]

expedited by 2 months from the 2015 CCR Rule deadline for the reasons 
described above in Unit IV.A.2.a.ii of this preamble. Because EPA is 
proposing that the fugitive dust control plan would be due on the 
effective date of the final rule, this would mean that the first annual 
report would be due one year after the plan is developed. The owner or 
operator has completed the annual CCR fugitive dust control report when 
the plan has been placed in the facility's operating record.
iii. Weekly Inspections of the Legacy CCR Surface Impoundment and 
Monthly Monitoring of the CCR Unit's Instrumentation
    EPA is proposing that owners and operators of legacy CCR surface 
impoundments must initiate the inspection requirements set forth in 
Sec.  257.83(a) no later than the effective date of the final rule. 
See, proposed regulatory text at Sec.  257.100(f)(3)(ii). Under Sec.  
257.83(a), all CCR surface impoundments must be examined by a qualified 
person at least once every seven days for any appearance of actual or 
potential structural weakness or other conditions that are disrupting 
or that have the potential to disrupt the operation or safety of the 
CCR unit. The results of the inspection by a qualified person must be 
recorded in the facility's operating record. Weekly inspections are 
intended to detect, as early as practicable, signs of distress in a CCR 
surface impoundment that may result in larger more severe conditions. 
Inspections are also designed to identify potential issues with 
hydraulic structures that may affect the structural safety of the unit 
and impact its hydraulic and hydrologic capacity. Section 257.83(a) 
also requires the monitoring of all instrumentation supporting the 
operation of the CCR unit to be conducted by a qualified person no less 
than once per month. See also 80 FR 21394-21395 (April 17, 2015).
    EPA recognizes that field work may be necessary prior to initiating 
weekly inspections, such as hiring a contractor to perform vegetative 
clearing and establishing inspection routes. If necessary, these 
activities may take 2-4 weeks. EPA also acknowledges that 
instrumentation may already be installed as part of dam safety or other 
programs under state regulations. However, if instrumentation is not 
currently installed, 4-6 weeks may be needed for the installation of 
piezometers or other equipment. Based on these estimates, EPA's 
proposed deadline for the initiation of weekly inspections and monthly 
monitoring of no later than the effective date of the final rule is 
sufficient for the completion of these activities. The proposed 
timeframe is the same as the 2015 CCR Rule deadline.
iv. Initial Annual Inspection for Legacy CCR Surface Impoundments
    EPA is proposing that owners and operators of legacy CCR surface 
impoundments must conduct the initial annual inspection no later than 3 
months after the effective date of the final rule. See, proposed 
regulatory text at Sec.  257.100(f)(3)(iv). Existing CCR surface 
impoundments exceeding the height and storage volume thresholds in 
Sec.  257.73(b) and (c), are required to conduct annual inspections of 
the CCR unit throughout its operating life (Sec.  257.83(b)). These 
inspections are focused primarily on the structural stability of the 
unit and must ensure that the operation and maintenance of the unit is 
in accordance with recognized and generally accepted good engineering 
standards. Each inspection must be conducted and certified by a P.E. 
See also 80 FR 21395, April 17, 2015.
    Annual inspections include documentation review, a visual 
inspection of the CCR unit, and a visual inspection of any hydraulic 
structures underlying the base of the CCR unit or passing through the 
CCR unit's dike. Documentation reviewed as part of the annual 
inspection include operating records, previous structural stability 
assessments, and the results of previous weekly, monthly, and annual 
inspections and can overlap with reviews needed to complete the initial 
structural stability assessment.
    EPA is proposing that owners and operators must prepare the initial 
inspection report for legacy CCR surface impoundments within the same 
timeframe--no later than 3 months from the effective date of the final 
rule--as was required for existing CCR surface impoundments in the 2015 
CCR Rule. The Agency believes this timeframe to prepare the initial 
annual inspection is similarly appropriate for legacy CCR surface 
impoundments as for existing impoundments. As discussed in the preamble 
to the 2015 CCR Rule, the 3-month timeframe was based on EPA's 
experience with its CCR Assessment Program to evaluate the structural 
stability and safety of existing impoundments throughout the nation. 
Specifically, EPA found that 3 months would be adequate to complete the 
tasks supporting an annual inspection, including retaining the services 
of a P.E., reviewing relevant information in the facility's operating 
record, conducting the field inspection, and completing the inspection 
report. See 80 FR 21395 (April 17, 2015).
v. Initial Inflow Design Flood Control System Plan for Legacy CCR 
Surface Impoundments
    EPA is proposing that owners and operators of legacy CCR surface 
impoundments must prepare the inflow design flood control system plan 9 
months after the effective date of the final rule. See, proposed 
regulatory text at Sec.  257.100(f)(3)(v). Owners or operators of all 
CCR surface impoundments are required to design, construct, operate, 
and maintain hydraulic and hydrologic capacity to adequately manage 
flow both into and from a CCR surface impoundment during and after the 
peak discharge resulting from the inflow design flood, which is based 
on the Hazard Potential Classification of the CCR surface impoundment 
(Sec.  257.82(a)). The regulation also requires the preparation of an 
initial inflow design flood control system plan (Sec.  257.82(c)). See 
also 80 FR 21390-21392, April 17, 2015.
    The primary activities associated with developing an inflow design 
flow control system can be summarized as document review, a site visit, 
hydrologic and hydraulic analyses (as needed), and report generation. 
Typically, owners and operators hire a P.E.-certified contractor, 
which, as described above, may take 1-2 weeks. The contractor would 
then perform a site visit (estimated to take one week) and review 
available pertinent documentation, such as topographical maps, aerial 
images, areal hydrological data, the unit's design drawings, the unit's 
construction reports, as-builts for the unit, previous area-capacity 
curves, and surface elevation data. EPA anticipates that many of these 
documents overlap with documents necessary for the history of 
construction report, hazard potential classification assessment, 
structural stability assessment, safety factor assessment, and annual 
inspection requirements, all of which are due no later than 3 months 
after the effective date of the final rule. Assuming all preceding 
analyses required by this rule are completed by their deadlines of 3 
months after the effective date of the final rule, the review is 
estimated to take 4-6weeks. Additional analyses, such as site-specific 
flood modeling and hydrologic and hydraulic (H/H) capacity 
calculations, may be needed to determine site-specific hydrological 
conditions or determine if the current H/H capacity is sufficient. 
These additional analyses are estimated to take

[[Page 32003]]

4-6 weeks. Finally, the contractor would generate the P.E.-certified 
inflow design flood control system plan documenting the design and 
construction of the flood control system, which may take another 4-6 
weeks. Based on these estimates, the total time needed to prepare an 
initial inflow design control system plan is 14 to 21 weeks. Therefore, 
EPA is proposing a deadline of 9 months after the effective date of the 
final rule for this requirement. EPA believes this timeline is 
sufficient to develop the plan while accounting for the three months 
allotted for the prerequisite assessments. This is expedited from the 
deadline in the 2015 CCR Rule by three months for reasons described 
here in Unit IV.A.2.a.ii of this preamble.
f. Groundwater Monitoring and Corrective Action Criteria for Legacy CCR 
Surface Impoundments
    The existing groundwater monitoring criteria in Sec. Sec.  257.90 
through 257.95 require an owner or operator of a CCR unit to install a 
system of monitoring wells and specify procedures for sampling these 
wells. Further, it sets forth methods for analyzing the groundwater 
data collected to detect hazardous constituents (e.g., toxic metals) 
and other monitoring parameters (e.g., pH, total dissolved solids) 
released from the units. 40 CFR 257.93. Once a groundwater monitoring 
system and groundwater monitoring program have been established for a 
CCR unit the owner or operator must conduct groundwater monitoring and, 
if the monitoring demonstrates an exceedance of the groundwater 
protection standards for identified constituents in Appendix IV of part 
257, corrective action is required. These requirements apply throughout 
the active life and post-closure care period of the CCR unit.
    There was widespread agreement among the commenters on the ANPRM 
that groundwater monitoring requirements would be appropriate for 
legacy CCR surface impoundments. However, some commenters argued that 
federal requirements would be duplicative and unnecessary. They 
suggested that EPA should allow facilities to demonstrate (through EPA 
review and approval) that the federal groundwater monitoring 
requirements are not necessary because existing groundwater monitoring 
systems established under state requirements meet the RCRA subtitle D 
protectiveness standard. These commenters said that overlapping federal 
and state groundwater monitoring and corrective action requirements 
would create regulatory uncertainty, potentially interfering with site-
specific plans designed to protect the environment and would ultimately 
delay work.
    EPA is proposing to require legacy CCR surface impoundments to 
comply with the existing groundwater monitoring and corrective action 
requirements with one revision, described below, to require sampling 
and analysis of constituents listed in Appendix IV at the same time as 
those listed in Appendix III. The existing groundwater monitoring and 
corrective action requirements are essentially the same requirements 
that have been applied to both hazardous waste and municipal solid 
waste disposal units for decades, and with the one exception discussed 
below, there is nothing about legacy units that makes them distinct 
enough to warrant separate requirements. EPA disagrees that it would be 
appropriate as part of this rulemaking to allow facilities to 
demonstrate (through EPA review and approval) that existing groundwater 
monitoring systems established under different state requirements could 
substitute for federal requirements. As EPA has previously explained, 
in RCRA section 4005(d), Congress established specific standards and 
mandated the process for EPA to determine that state requirements 
should operate in lieu of the federal. Under those provisions, a State 
can apply to obtain authorization from EPA to operate its program 
(either in whole or in part) in lieu of the federal requirement by 
demonstrating that either of the standards in RCRA section 
4005(d)(1)(B) has been met. Relying on that congressionally mandated 
process, rather than a separate process created in this rulemaking, is 
the appropriate route to address the commenters concerns about 
duplication between federal and state requirements.
i. Design and Installation of the Groundwater Monitoring System for 
Legacy CCR Surface Impoundments
    EPA is proposing that owners and operators of legacy CCR surface 
impoundments install the groundwater monitoring system as required by 
Sec.  257.91 no later than six months from the effective date of the 
final rule. See, proposed regulatory text at Sec.  257.100(f)(4)(i). 
Existing monitoring wells can be used as a part of that system provided 
that they meet the federal criteria. Commenters on the ANPRM explained 
that in some states, the state may require the owner or operator to 
receive state approval before they can install a groundwater monitoring 
system. Therefore, the commenters said that one year is inadequate to 
conduct these activities and two years is a more reasonable timeframe 
in which to carry out these activities. EPA disagrees that 12 months 
from the publication date (i.e., 6 months from the effective date) 
would provide an insufficient amount of time to install groundwater 
monitoring wells. In the 2015 CCR Rule, EPA allotted 36 months total 
(from publication) for facilities to both install the wells and 
complete their baseline sampling. Based on the amount of time most 
facilities needed to complete or to collect baseline sampling, EPA 
calculates that facilities were able to install wells within a single 
year.
    To complete the installation of the groundwater monitoring system, 
the first activity to meet Sec.  257.91(f) may include hiring a 
contractor that is a qualified P.E. (estimate 1-2 weeks). The next 
activity may be to develop a workplan that determines the number, 
location, and depths of monitoring wells, which assumed to be developed 
based on available historic site characterization information including 
hydrogeologic setting, engineering design of the CCR unit or other 
information that may already be compiled in the history of construction 
requirement (Sec.  257.73(c)(1)) (estimate 7-9 weeks). Note that any 
additional site characterization is assumed to occur concurrently with 
the monitoring well installation. Subsequently, site reconnaissance may 
be performed along with vegetative clearing and utility locating, and 
the workplan may be modified to adjust for field conditions as needed 
(estimate 2 weeks when considering the installation of 10 monitoring 
wells). The next activity is to drill to depth, install and develop the 
10 monitoring wells. The time to drill to depth can vary widely based 
on the drilling technique, subsurface lithology, site-specific 
conditions, weather, and other factors. It is estimated that a 100 foot 
well can be drilled to depth in 5 days at the rate of 20 feet/day. For 
10 monitoring wells, the time to drill to depth is assumed to take 10 
weeks. The monitoring wells must then be properly installed and 
constructed in accordance with Sec.  257.91(e) and other requirements. 
Monitoring well development is assumed to take 3 days per well or 30 
days for all 10 wells. The last activity is to develop documentation 
that records the design, installation, and development of the 
monitoring wells, subject to P.E. certification and submit monitoring 
well construction records to the appropriate state and federal agencies 
(estimate 4-6 weeks). Based on these assumptions, the total time

[[Page 32004]]

estimated for installation of a groundwater monitoring system is 
approximately 27-32 weeks, or 7-8.5 months. This deadline includes an 
additional 3.5-month buffer to adjust for delays in the field, 
installation of new additional wells, additional site characterization 
of newly discovered pertinent subsurface features (e.g., faults, karst 
features) or other modifications to the workplan based on site-specific 
information gained during the monitoring well installation. Thus, EPA 
is proposing to require the installation of the groundwater monitoring 
system no later than 6 months after the effective date of the final 
rule.
ii. Development of the Groundwater Sampling and Analysis Program for 
Legacy CCR Surface Impoundments
    EPA is proposing to require owners and operators of legacy CCR 
surface impoundments to comply with the existing groundwater sampling 
and analysis program requirements for CCR surface impoundments, 
including the selection of the statistical procedures that will be used 
for evaluating groundwater monitoring data. 40 CFR 257.93. See, 
proposed regulatory text at Sec.  257.100(f)(4)(ii).
    Recommendations and information on how to comply with many of the 
requirements for the groundwater sampling and analysis program (e.g., 
analytical procedures, QA/QC controls, sampling protocol) can be found 
in the following EPA guidance documents (e.g., RCRA Groundwater 
Monitoring: Draft Technical Guidance, 1992, EPA/530/R-93/001; Low-Flow 
(Minimal Drawdown) Ground-Water Sampling Procedures, 1996, EPA/540/S-
95/504). To develop the groundwater sampling and analysis program, the 
first steps would be to hire a contractor (1 to 2 weeks), review the 
groundwater monitoring system installation and other pertinent records 
(2 to 4 weeks), and develop the groundwater sampling and analysis 
program (4 to 6 weeks). Sometimes in complex hydrogeological settings 
(e.g., groundwater flow reversals surrounding CCR units adjacent to a 
large river), additional information from synoptic groundwater 
elevations may be necessary to refine the sampling program (e.g., 
establish upgradient/downgradient wells) (estimate 2 weeks). Based on 
these assumptions, the total time estimated to develop a groundwater 
sampling and analysis program is 9 to 14 weeks. The groundwater 
sampling and analysis program must include the list of monitoring wells 
to be sampled (e.g., sampling network). However, the list of monitoring 
wells to be sampled can only be determined after installation of the 
groundwater monitoring system which is estimated to take 7 to 8.5 
months. If it is assumed that the sampling and analysis program is 
developed (~2 to 3.5 months) only after the installation of the 
monitoring network (7.5 to 8 months), the total time needed to meet 
this requirement is estimated at approximately 9.5 to 11.5 months. 
Therefore, building in some buffer time to account for any possible 
delays due to complex hydrogeological settings, EPA is proposing that 
the sampling and analysis program can be developed no later than 6 
months after the effective date of the final rule.
iii. Detection Monitoring Program and Assessment Monitoring Program 
Combined
    To expedite groundwater monitoring and the initiation of corrective 
measures, EPA is proposing to require sampling and analysis of 
constituents listed in Appendix IV at the same time as those listed in 
Appendix III. The combined sampling and analysis of all Appendices III 
and IV constituents will expedite the initiation of corrective 
measures, where needed, by at least 6 months.
    The existing CCR regulations establish a phased groundwater 
monitoring program, consisting of a separate detection monitoring 
program, assessment monitoring program, and corrective action program. 
Groundwater monitoring begins with detection monitoring by conducting 
statistical comparisons between (1) the background level of a 
constituent measured in one or more upgradient wells and (2) the level 
of that same constituent in a downgradient well. The constituents 
monitored in detection monitoring are listed in Appendix III and are 
generally constituents that are designed to provide early evidence of a 
potential release (e.g., are highly mobile). If the concentration of 
the constituent in the downgradient well is higher than the background 
concentration by a statistically significant amount, (i.e., a 
statistically significant increase (SSI) over background has been 
detected), this provides evidence of a potential release from the unit.
    If an SSI is detected, the owner or operator must proceed to the 
next step, assessment monitoring. Assessment monitoring requires 
sampling and analysis for the full list of constituents included in 
Appendix IV. In assessment monitoring, concentrations of each Appendix 
IV constituent at downgradient wells are compared to a groundwater 
protection standard established for each constituent (either a 
background level or a regulatory limit). Whenever assessment monitoring 
results indicate a statistically significant level (SSL) exceeding the 
groundwater protection standard has been detected at a downgradient 
well for any of the Appendix IV constituents, the facility must start 
the process for cleaning up the contamination by characterizing the 
nature and extent of the release and of site conditions that may affect 
the cleanup, and by initiating an assessment of corrective measures.
    EPA is proposing to require that facilities simultaneously initiate 
sampling and analysis of all Appendix III and IV constituents at legacy 
CCR surface impoundments to expedite the cleanup of contamination from 
these abandoned unlined impoundments. EPA is proposing no other 
revisions to the existing groundwater monitoring requirements in 
Sec. Sec.  257.90 through 257.95.
    Although in 2015 EPA applied the same groundwater monitoring 
requirements to both existing and new CCR units, the phased approach to 
groundwater monitoring is best suited to situations where there is 
little likelihood of pre-existing contamination, such as for new units. 
A phased approach provides for a graduated response over time to the 
problem of groundwater contamination as the evidence of such 
contamination increases. This allows for proper consideration of the 
transport characteristics of CCR constituents in groundwater, while 
protecting human health and the environment. In contrast, at sites 
where the unit has potentially been leaking for a long period of time, 
these advantages are outweighed by the need to protect human health and 
environment by quickly detecting the constituents of concern in 
Appendix IV to expedite any necessary corrective action. See, USWAG 901 
F.3d at 427-30. Moreover, there is good reason to believe that many 
legacy CCR surface impoundments are contaminating groundwater, given 
the large number of presently regulated CCR surface impoundments that 
have been found to be leaking.
iv. Detection Monitoring Program and Assessment Monitoring Program--
Deadline for Collection and Analyses of Eight Independent Samples for 
Legacy CCR Surface Impoundments
    EPA is proposing that no later than 24 months after the effective 
date of the final rule, owners or operators of legacy CCR surface 
impoundments initiate the detection monitoring program by

[[Page 32005]]

completing sampling and analysis of a minimum of eight independent 
samples for each background and downgradient well, as required by Sec.  
257.94(b). See proposed regulatory text at Sec.  257.100(f)(4)(iii). 
Within 90 days after that, they must identify any SSIs over background 
levels for the constituents listed in Appendix III, as required by 
Sec.  257.94. To expedite the time to initiate any required corrective 
action, EPA is also proposing that by this same deadline they initiate 
the assessment monitoring program by establishing groundwater 
protection standards and beginning the evaluation of the groundwater 
monitoring data for an SSL over groundwater protection standards for 
the constituents listed in Appendix IV as required by Sec.  257.95. 
Then, if an SSL over a groundwater protection standard (GWPS) for any 
of the constituents listed in Appendix IV is found, the owner or 
operator of the legacy CCR surface impoundment must perform any 
required corrective action in accordance with Sec. Sec.  257.96 through 
257.98.
    Several commenters on the ANPRM stated that it would be appropriate 
to have a fully operational groundwater monitoring systems in place and 
begin detection monitoring two years from the rule's effective date and 
then to follow the same groundwater monitoring requirements as units 
subject to the 2015 CCR Rule. These commenters said that as important 
as it is to begin detecting and addressing releases to groundwater, it 
is equally important that these complex systems be designed and 
installed correctly. According to the commenters, the design and 
installation of a groundwater monitoring system generally entails a 
number of activities, many of which must occur sequentially, including 
determining the uppermost aquifer, deciding whether to install a single 
or multiunit monitoring system, collecting and evaluating 
hydrogeological information that can be used to model the site, 
characterizing the site geology, characterizing the groundwater flow 
beneath the site, determining the flow direction and hydraulic 
gradient, establishing horizontal and vertical flow direction, 
determining hydraulic conductivity, determining groundwater flow rate, 
determining the monitoring wells' placement, selecting the drilling 
method, designing the monitoring wells, developing sampling and 
analysis procedures, choosing a statistical method for evaluating the 
data, and beginning detection monitoring.
v. Initial Groundwater Monitoring and Corrective Action Report for 
Legacy CCR Surface Impoundments
    EPA is proposing to apply the existing requirements in Sec.  
257.90(e) to legacy CCR surface impoundments and that owners and 
operators of legacy CCR surface impoundments comply no later than 
January 31 of the year following the calendar year a groundwater 
monitoring system has been established (and annually thereafter). See 
proposed regulatory text at Sec.  257.100(f)(4)(iv). This requires the 
preparation of an annual groundwater monitoring and corrective action 
report. The report must contain specific information identified in the 
regulations, including but not limited to maps; aerial images or 
diagrams showing the CCR unit and all upgradient (background) and 
downgradient wells; identification of any monitoring wells installed or 
decommissioned in the previous year; monitoring data collected under 
Sec. Sec.  257.90 through 257.98, and a narrative discussion of any 
transition between monitoring programs (i.e., detection and assessment 
monitoring). Since EPA is proposing to expedite the baseline monitoring 
initiation of detection monitoring, and initiation of assessment 
monitoring, the requirement to prepare and post the first annual 
groundwater monitoring and corrective action report should also be 
expedited. This will allow the public to review the groundwater 
monitoring results.
g. Closure and Post-Closure Care Criteria for Legacy CCR Surface 
Impoundments
    The existing closure and post-closure care criteria in Sec. Sec.  
257.101 through 257.104 establish specific performance standards 
relating to the closure and the subsequent monitoring and maintenance 
of CCR units. These criteria are essential to ensuring the long-term 
safety of closing CCR units. A brief overview of the existing 
requirements is presented in Unit IV.A.2.f.i of this preamble.
    The regulations currently provide two options for closing a CCR 
unit: closure by removal and closure with waste in place. See Sec.  
257.102(a). Each option establishes specific performance standards that 
must be met in their entirety. See Sec.  257.102(c) and (d). If the 
performance standards for each option can both be met, the regulations 
allow a facility to select either of the options. However, a facility 
must meet all of the performance standards for the closure option it 
has selected, and if it cannot meet all of the performance standards 
for one option, then it must select the other option and meet all of 
the performance standards for that option. See Sec.  257.102(a).
    The existing CCR regulations also include timeframes to initiate 
and complete closure activities, as well as criteria under which owners 
or operators may obtain time extensions due to circumstances beyond the 
facility's control. See Sec. Sec.  257.101 through 257.102. Finally, 
owners and operators are required to prepare closure and post-closure 
care plans describing these activities. See Sec. Sec.  257.102(b), 
257.104(d). EPA is proposing to make the existing regulations 
applicable to legacy CCR surface impoundments as discussed specifically 
below.
    First, based on the data gathered since 2015 from the currently 
regulated CCR unit universe, the Agency considers it highly unlikely 
that any legacy CCR surface impoundment has a composite liner that 
meets the requirements of Sec.  257.71. EPA analyzed the list of 
inactive CCR facilities provided in the ANPRM comments and knows that 
almost all these facilities were opened prior to 1990 (one facility 
opened in 1996) before composite liner systems were typically 
installed. Unless legacy CCR surface impoundments are very different 
than impoundments at active facilities, EPA expects units of this age 
to be unlined as defined by Sec.  257.71. Consistent with the USWAG 
decision and the existing regulations in Sec.  257.101(a) mandating 
that all unlined (including clay-lined) impoundments must close, EPA is 
proposing to explicitly require that all legacy CCR surface 
impoundments initiate closure within 12 months of the effective date of 
final rule, rather than simply relying on the existing provision in 
Sec.  257.101(a). See, proposed regulatory text at Sec.  257.101(e). 
Legacy CCR surface impoundments pose unacceptable risks because they 
continue to impound liquid, even if closure has been initiated or a 
cover system has been installed.
    Second, EPA is proposing to explicitly state that the alternative 
closure demonstration provisions in Sec.  257.103(f) would not be 
applicable to legacy CCR surface impoundments. As a legacy CCR surface 
impoundment, by definition, is an inactive impoundment at an inactive 
facility, EPA does not believe that any facility will need to continue 
to use the unit. Because a continued need to use the disposal unit is a 
critical component of the alternative closure demonstrations, it 
appears that no legacy CCR surface impoundment could qualify under the 
existing provisions. Accordingly, EPA does not believe these provisions 
are relevant to legacy CCR surface impoundments.

[[Page 32006]]

i. ANPRM Comments Regarding Closure
    Commenters on the ANPRM generally agreed that closure requirements 
are appropriate for legacy CCR surface impoundments. However, they 
disagreed on the precise requirements that would be appropriate. Some 
commenters said a legacy CCR surface impoundment that has been closed 
in place must be required to re-close if not closed in a manner that 
meets or exceeds the 2015 CCR Rule's provisions for closure in place. 
They also said that EPA must not exempt legacy CCR surface impoundments 
from closure requirements unless the impoundment was closed in full 
compliance with either the closure mandate for removal set out at Sec.  
257.102(c), or the closure performance standards, drainage and 
stabilization directives, and cover system requirements set out at 
Sec.  257.102(d).
    Other commenters on the ANPRM agreed that closure and post-closure 
requirements would be appropriate for legacy CCR surface impoundments 
but stated that the requirements should account for distinctive 
elements of some legacy CCR surface impoundments. According to these 
commenters, over decades, some legacy CCR surface impoundments have 
become ecosystems that support protected species or feature wetlands. 
These commenters raised concern that closure activities could 
compromise these ecosystems or species whereas leaving the environment 
undisturbed is preferable. These commenters stated that if EPA requires 
closure of these units, owners should not be required to obtain 
necessary approvals or mitigate impacts to aquatic resources or 
protected species under other laws. One commenter on the ANPRM said EPA 
should not require legacy CCR surface impoundments completing closure 
by removal to meet the groundwater performance standards.
    Some commenters said EPA should rely on RCRA section 1006(b) to 
include a provision in any final rule addressing legacy CCR surface 
impoundments that any closure plan for a legacy CCR surface impoundment 
approved by a state or federal agency prior to the effective date of 
any new regulations would be considered compliant with the new 
regulations. According to these commenters, many units are or will be 
in the process of closing impoundments pursuant to consent orders, 
agreements, and/or state regulatory programs, and forcing units that 
are in active closure or that have completed closure to comply with a 
new set of requirements risks undoing the careful planning that has 
already occurred with state or federal agencies. These commenters 
further stated that ``such redundant and retroactive regulation also 
risks delaying the closure process and requiring closure work to be 
redone.'' According to these commenters, confirming that units 
implementing closure plans approved by a state or federal agency would 
be deemed compliant with the final legacy CCR surface impoundment 
regulations (or that the underlying units are otherwise exempt from the 
final regulations) would avoid duplicative, retroactive regulation of 
such units, and would allow the regulated community and impacted states 
to rely on the closure plans already in place, and would prevent any 
delay in completion of closure activities that could be attributed to 
uncertainty of the application of requirements for the final rule.
    Although several commenters alleged that the closure of legacy CCR 
surface impoundments would itself present greater risks than leaving 
the disposal unit in its existing state, no commenter presented any 
data or analysis to support their claims. EPA also lacks a factual 
basis to exempt legacy CCR surface impoundments in the process of 
completing closure by removal from the requirement to meet the 
groundwater performance standards. In the absence of any record to 
support a conclusion that these suggestions meet the statutory standard 
in RCRA section 4004(a), EPA cannot adopt them. EPA invites comments 
from those with concrete data or analysis, if any, about any specific 
legacy CCR surface impoundments as it relates to these questions.
    EPA also disagrees that it would be appropriate to establish an 
exemption for facilities that are currently in the process of closing 
under state requirements. The commenters provided no factual record of 
the various state information regarding particular state requirements, 
but merely generically reference the existence of state requirements. 
This is insufficient information for the Agency to evaluate how the 
state requirements compared to the federal requirements. Such a factual 
record would be necessary to support any kind of exemption or other 
action pursuant to RCRA section 1006(b). More to the point, as 
discussed previously, the appropriate mechanism to address concerns 
about potentially duplicative state and federal requirements is through 
Congressionally-mandated process in RCRA section 4005(d), under which a 
state seeks approval to operate its permit program in lieu of the 
federal program, rather than this rulemaking.
ii. Preparation of a Written Closure Plan for Legacy CCR Surface 
Impoundments
    EPA is proposing that owners and operators of legacy CCR surface 
impoundments comply with the existing requirements of Sec.  257.102(b) 
requiring the preparation of a written closure plan. See proposed 
regulatory text at Sec.  257.100(f)(5)(i). The closure plan describes 
the steps necessary to close a CCR unit at any point during the active 
life of the unit based on recognized and generally accepted good 
engineering practices. 40 CFR 257.102(b)(1). The plan must set out 
whether the closure of the CCR unit will be accomplished by leaving CCR 
in place or through closure by removal and include a written narrative 
describing how the unit will be closed in accordance with the section, 
or in other words, how the closure will meet all the performance 
standards in the regulations. 40 CFR 257.102(b)(1)(i). If the CCR is 
left in place, the closure plan must include a description of the final 
cover system and how the final cover system will achieve the regulatory 
performance standards. If the base of the impoundment intersects with 
groundwater, the closure plan would need to discuss the engineering 
measures taken to ensure that the groundwater had been removed from the 
unit prior to the start of installing the final cover system, as 
required by Sec.  257.102(d)(2)(i). The closure plan would also need to 
describe how the facility plans to meet the requirements in Sec.  
257.102(d)(1) to ``control, minimize or eliminate, to the maximum 
extent feasible, post-closure infiltration of liquids into the waste 
and releases of CCR, leachate, or contaminated run-off to the ground or 
surface waters.'' This could include for example, the installation of 
engineering controls that would address the post-closure infiltration 
of liquids into the waste from all directions, as well as any post-
closure releases to the groundwater from the sides and bottom of the 
unit. The written closure plan must also provide a schedule for 
completing all activities necessary to satisfy the closure criteria of 
the rule. See also 80 FR 21410-21425, April 17, 2015.
    Some commenters said EPA should provide phased and reasonable 
compliance deadlines for the development of closure plans prior to 
initiation of any groundwater monitoring or closure work. Other 
commenters acknowledged the Agency provided 18 months from promulgation 
of the 2015 CCR Rule for plants to develop their closure and post-
closure plans and that the amount of time was

[[Page 32007]]

partly dictated by the Agency's commitment to harmonizing the 2015 CCR 
Rule with the ELG Rule. Commenters shared that consideration of new ELG 
requirements would not be an issue for legacy CCR surface impoundments; 
therefore, a shorter planning horizon is reasonable for legacy CCR 
surface impoundments such as 6 months from the effective date of a 
legacy CCR surface impoundment rule. The commenters further said that 
planning is only the first step while unit closure itself can take 
years depending on factors such as the size and type of unit. Legacy 
CCR surface impoundments would likely require similar closure 
timeframes, and possibly additional time if site-specific 
accommodations are required such as the presence of a listed or 
endangered species. Some commenters agreed that the closure timeframe 
provided in the 2015 CCR Rule may be reasonable for legacy CCR surface 
impoundments. Other commenters said six months should be the bare 
minimum for owners to develop any closure and post-closure care plans 
for legacy CCR surface impoundments as closure activities cannot begin 
until the closure plan is in place.
    When preparing the closure plan, the owner or operator would first 
need to hire a contractor to complete the report (1-2 weeks). Next, it 
is assumed that the contractor will need to review site-specific 
documents, assessments, and analyses that were completed earlier to 
meet requirements for other parts of the rule that may impact the 
closure plan. Examples of existing documents and assessments reviewed 
may include history of construction, initial structural stability 
assessment, initial safety factor assessment, initial hazard potential 
classification, hydraulic and hydrologic analyses for inundation maps 
and potential impact area, annual inspections, groundwater monitoring 
system, and groundwater sampling and analysis reports. Assuming all 
preceding analyses are completed by their deadlines of 6 months after 
the effective date of the final rule, the next step is to review 
existing documents and assessments (estimate 4-6 weeks). The next step 
is to prepare the written closure plan with the requirements in Sec.  
257.102(b) through (j). Since the listed activities are primarily 
desktop-related and depend on predecessor requirements, EPA is 
proposing a deadline of 12 months after the effective date of the rule 
to complete the closure plan. EPA is expediting this deadline for the 
reasons described above in Unit IV.A.2.a.ii of this preamble.
iii. Preparation of a Written Post-Closure Care Plan for Legacy CCR 
Surface Impoundments
    EPA is proposing that owners and operators of legacy CCR surface 
impoundments would be required to comply with the existing requirement 
in Sec.  257.104(d) regarding the preparation of a written post-
closure. See, proposed regulatory text at Sec.  257.100(f)(5)(ii). 
Section 257.104(d) requires that an owner or operator of a CCR unit 
prepare a written post-closure plan. The content of the plan includes 
among other things, a description of the monitoring and maintenance 
activities required for the unit and the frequency that these 
activities will be performed.
    When developing the post-closure care plan, EPA assumes the 
contents of the P.E.-certified plan are stated in the rule Sec.  
257.104(d)(1)(i) through (iii) and can be summarized as planned 
monitoring and maintenance activities, contact information during post-
closure care period and planned uses of the property. The steps to 
prepare the post-closure care plan are assumed to be the same as the 
closure plan, with different analysis needed for the post-closure care 
period. Since the listed activities are primarily desktop-related and 
depend on a number of predecessor requirements, described in Unit 
IV.A.2.g.i of this preamble, related to the closure plan, EPA is 
proposing to require the post-closure care plan no later than 12 months 
after the effective date of the final rule. EPA is expediting this 
deadline for the reasons described above in Unit IV.A.2.a.ii of this 
preamble.
iv. Initiation of Closure for Legacy CCR Surface Impoundments
    As discussed above, the current record indicates that legacy CCR 
surface impoundments are largely, if not entirely, unlined, and 
therefore, EPA is proposing that they be subject to the existing 
requirement to initiate closure that are applicable to other unlined 
CCR surface impoundments. See 40 CFR 257.101. Specifically, EPA is 
proposing that owners and operators of legacy CCR surface impoundments 
initiate closure no later than 12 months after the effective date of 
the final rule. See proposed regulatory text at Sec.  257.101(e)(1). 
This is 30 months sooner than the earliest date under the 2015 CCR Rule 
that owners or operators of CCR units were required to initiate closure 
and is expedited for the reasons described above in Unit IV.A.2.a.ii of 
this preamble. EPA considered requiring initiation of closure sooner 
but believes that 12 months is the minimum amount of time necessary to 
collect the information needed to determine whether to close the unit 
in place or close by removal. Such information would include the 
identification and delineation of the legacy CCR surface impoundment, 
the structural stability of the unit, the hydrogeology of the site, and 
other site characteristics of the site, and whether any of the 
uppermost aquifer has been contaminated, as well as any other relevant 
engineering information needed to design the closure. Because many of 
the legacy CCR surface impoundments have not been monitored for some 
time, this information may not be currently available. However, most of 
this information can be obtained through compliance with the 
groundwater monitoring and corrective action requirements that EPA is 
proposing to establish, as discussed above. Twelve months will provide 
sufficient time to complete the steps necessary to obtain this 
information. Once the owner and/or operator has the necessary 
information, they can develop a closure plan and initiate closure.
    One commenter said there should be no mechanism to extend the time 
to initiate closure. EPA agrees and, consistent with the existing 
requirements for inactive unlined impoundments in Sec.  257.101(a), the 
Agency is not proposing to establish a mechanism to extend the deadline 
to initiate closure.
    Finally, as an alternative to requiring the closure of a legacy CCR 
surface impoundment, the Agency solicits comment on whether the 
regulations should provide owners and operators the option to retrofit 
a legacy CCR surface impoundment in accordance with the retrofit 
requirements in Sec.  257.102(k).
v. Deadline To Complete Closure for Legacy CCR Surface Impoundments
    The existing CCR regulations currently require (at Sec.  
257.102(f)) an owner or operator of existing and new CCR surface 
impoundments generally to complete closure activities within five years 
from initiating closure. The regulations also establish the conditions 
for extending this deadline, as necessary, including documentation 
requirements. EPA is proposing that owners and operators of legacy CCR 
surface impoundment comply with the existing closure completion 
timeframes in Sec.  257.102(f). Most commenters agreed that units 
should be provided the same amount of time to complete closure as in 
the existing provisions.

[[Page 32008]]

vi. Post-Closure Care for Legacy CCR Surface Impoundments
    The existing post-closure care criteria require the monitoring and 
maintenance of units that have closed in place for at least 30 years 
after closure has been completed. 40 CFR 257.104. During this post-
closure period, the facility would be required to continue groundwater 
monitoring and corrective action, where necessary. EPA is proposing to 
apply these existing requirements to legacy CCR surface impoundments 
without revision. These criteria are essential to ensuring the long-
term safety of legacy CCR surface impoundments.
h. Recordkeeping, Notification, and Internet Posting Criteria for 
Legacy CCR Surface Impoundments
    The 2015 CCR Rule required at Sec. Sec.  257.105 through 257.107 
for owner or operators of CCR units to record certain information in 
the facility's operating record. In addition, owners and operators are 
required to provide notification to states and/or appropriate Tribal 
authorities when the owner or operator places information in the 
operating record, as well as to maintain a CCR website for this 
information. Commenters on the ANPRM agreed that recordkeeping, 
notification and website reporting requirements are appropriate for 
legacy CCR surface impoundments.
    EPA is proposing that owners and operators of legacy CCR surface 
impoundments be subject to the existing recordkeeping, notification and 
website reporting requirements in the CCR regulations. The CCR 
regulations require the owner or operator of a CCR unit(s) to maintain 
files of all required information (e.g., demonstrations, plans, 
notifications, and reports) that supports implementation and compliance 
with the rule. Each file must be maintained in the operating record for 
a period of at least five years following submittal of the file into 
the operating record. Submittal into the operating record is required 
at the time the documentation becomes available or by the specific 
compliance deadline. Section 257.105 contains a comprehensive listing 
of each recordkeeping requirement.
    Owners or operators are also required to notify State Directors 
and/or the appropriate Tribal authority when specific documents have 
been placed in the operating record and on the owner's or operator's 
CCR website. In most instances, these reports must be certified by a 
P.E. and may, in certain instances, be accompanied by additional 
information or data supporting the notification. Notification 
requirements can be found at Sec.  257.106, and are required for 
location criteria, design criteria, operating criteria, groundwater 
monitoring, corrective action, closure, and post-closure care.
    Commenters on the ANPRM agreed that owners or operators of CCR 
facilities should be required to establish a publicly accessible 
website where facilities are required to post relevant information 
demonstrating compliance with all applicable requirements. They agreed 
the website should not be hosted by the state or EPA. They also said 
the website should be required to be activated by the effective date of 
the final rule.
    EPA is proposing that owners and operators of legacy CCR surface 
impoundments are also required to establish and maintain a website 
titled, ``CCR Rule Compliance Data and Information.'' Unless provided 
otherwise in the rule, information posted to the publicly accessible 
internet site must be available for a period no less than 5 years from 
the initial posting date for each submission. Posting of information 
must be completed no later than 30 days from the submittal of the 
information to the operating record. EPA is proposing that owners and 
operators of legacy CCR surface impoundments have 30 days from the 
effective date of the final rule to post applicable information on 
their CCR website.

B. CCR Management Unit Requirements

    EPA is proposing to establish requirements to address the risks 
from currently exempt solid waste management of CCR that involves the 
direct placement of CCR on the land. Information obtained since 2015 
demonstrates that these exempt solid waste management practices are 
currently contaminating groundwater at many sites, and at others, have 
the potential to pose risks commensurate with the risks associated with 
currently regulated activities. The specific solid waste management 
activities at issue are: CCR disposal in surface impoundments and 
landfills that closed prior to the effective date of the 2015 CCR Rule, 
disposal in inactive CCR landfills, and any solid waste management that 
involves the placement or receipt of CCR directly on the land.
    As discussed in more detail below, EPA estimates that these solid 
waste management practices could pose lifetime cancer risks from 
arsenic as high as 2 x 10-5 to 1 x 10-3 (i.e., 2 
to 100 cases of cancer for every 100,000 individuals exposed), 
depending on the specific management practice. In addition, EPA has 
identified recent damage cases, described in Unit IV.B.2 of this 
preamble, indicating that these management practices have contaminated 
groundwater at currently regulated facilities,\15\ through releases of 
constituents commonly found in CCR, such as arsenic, lithium and 
molybdenum.
---------------------------------------------------------------------------

    \15\ Under part 257, subpart D, new and existing CCR landfills 
and surface impoundments, including any lateral expansions of these 
units, as well as inactive CCR surface impoundments are currently 
regulated.
---------------------------------------------------------------------------

    Based on these data, EPA is proposing to establish a new category 
of units that would be subject to a set of requirements tailored to the 
characteristics of such units and the risks that they present. These 
requirements would include the existing criteria in the CCR regulations 
for groundwater monitoring, corrective action, closure, and post-
closure care.
1. Risk Analysis of CCR Management Units
a. Summary of 2014 Risk Record
    EPA conducted a national-scale, probabilistic analysis in 2014 
titled, Human and Ecological Risk Assessment of Coal Combustion 
Residuals (2014 Risk Assessment),\16\ that characterized potential 
risks to human and ecological receptors associated with leakage from 
CCR surface impoundments and landfills in operation at that time. A 
combination of models was used to predict fate and transport of 
contaminants through the environment, receptor exposures, and the 
resulting risks to human and ecological receptors. The specific 
exposure routes evaluated were: (1) Human inhalation of particulate 
matter blown from open management units, (2) Human ingestion of crops 
and livestock raised on nearby fields, (3) Human ingestion of 
groundwater used as a source of drinking water, (4) Human ingestion of 
fish caught from freshwater streams, and (5) Ecological contact with 
and ingestion of surface water and sediment. Site-specific data were 
used where available, supplemented by regional and national data to 
fill data gaps, to capture the variability of waste management 
practices, environmental conditions, and receptor behavior. EPA 
reported risks for both highly exposed individuals and more moderately 
exposed individuals. Risks to highly exposed individuals represent a 
reasonable maximum estimate that members of the general population 
might be exposed to, which were

[[Page 32009]]

calculated as the 90th percentiles of all probabilistic model results. 
Risks to moderately exposed individuals represent a more typical 
estimate that members of the general population might be exposed to, 
which were calculated as the 50th percentiles of all probabilistic 
model results.
---------------------------------------------------------------------------

    \16\ U.S. EPA. 2014. ``Human and Ecological Risk Assessment of 
Coal Combustion Residuals.'' RIN 2050-AE81. Office of Solid Waste 
and Emergency Response. Washington, DC. December.
---------------------------------------------------------------------------

    Under RCRA, EPA typically relies on a risk range to determine the 
point at which regulation is appropriate. EPA uses as an initial cancer 
risk ``level of concern'' a calculated risk level of 1 x 
10-5 (one in one hundred thousand) or a hazard quotient (HQ) 
above 1.0 for any noncarcinogenic risks. For example, wastestreams for 
which the calculated high end individual cancer-risk level is 1 x 
10-5 or higher generally are considered candidates for 
regulation. Wastestreams whose risks are calculated to be 1 x 
10-4 (one in ten thousand) or higher generally will be 
considered to pose a substantial present or potential hazard to human 
health and the environment and generally will be regulated. 
Wastestreams for which these risks are calculated to be 1 x 
10-6 (one in one million) or lower, and lower than 1.0 HQ or 
environmental risk quotients for any noncarcinogens, generally will be 
considered not to pose a substantial present or potential hazard to 
human health and the environment and generally will not be regulated. 
See 80 FR 21449; 59 FR 66075-66077, December 22, 1994.
    EPA first evaluated national-scale risks, as documented in the 2014 
Risk Assessment, which provide a snapshot in time of potential risks 
across the country. This was accomplished by weighting risks from 
individual management practices in proportion to the anticipated 
prevalence of those practices. National-scale risks provide important 
context as to whether risks are a systemic issue that warrant national 
regulations or are limited in scope and better addressed through more 
targeted actions. The Agency's evaluation found that the management 
practices that EPA believed were generally in current use at surface 
impoundments and landfills were likely to pose risks to human health 
through groundwater exposure within the range that EPA typically 
considers warranting regulation. For highly exposed individuals, the 
cancer risks from arsenic due to the operation of surface impoundments 
were as high as 2 x 10-4 and noncancer risks from both 
lithium and molybdenum were as high as an HQ of 2, while the cancer 
risks associated with the operation of landfills were estimated to be 
as high as 5 x 10-6 from the ingestion of arsenic-
contaminated drinking water. In contrast, all risks for moderately 
exposed individuals fell below EPA's risk range. This was largely 
attributed to the fact that many facilities are located next to major 
water bodies and so contaminant plumes were frequently intercepted by 
these water bodies before they could reach private wells.
    EPA next evaluated the risks associated with individual management 
practices at surface impoundments and landfills. This was accomplished 
by filtering the national-scale model runs to focus only on those that 
included the practice of interest and using the filtered set of runs to 
calculate risks associated with that specific practice. These 
individual risks provide important context about the range of 
contaminants and practices that could pose risk at individual sites. 
The Agency's evaluation identified two specific management practices 
that could lead to risks higher than those identified in the national 
risk estimates.
    The first practice EPA evaluated was the disposal of CCR in unlined 
and clay-lined units. Management in unlined surface impoundments 
resulted in cancer risks for arsenic up to 3 x 10-4, as well 
as noncancer risks for lithium up to an HQ of 3, molybdenum up to an HQ 
of 4, and thallium up to an HQ of 2. Management in unlined landfills 
resulted in cancer risks for arsenic up to 2 x 10-5. The 
larger increase in arsenic risks identified for unlined landfills above 
those for national-scale landfills (2 x 10-5 vs. 5 x 
10-6) compared to unlined and national-scale impoundments (3 
x 10-4 vs. 2 x 10-4) is because a larger 
proportion of landfills nationwide were initially modeled as having a 
liner. Since promulgation of the 2015 CCR Rule, it has become clear 
that more landfills are unlined than originally estimated. Thus, it is 
anticipated that national-scale risks for landfills would actually be 
closer to those for unlined units (2 x 10-5), rather than 
the lower estimates reported in the 2014 Risk Assessment.
    Although clay-lined units tended to have lower risks than unlined 
units, they still had potential to result in risks within the range 
that EPA considers for regulation under RCRA. Management in clay-lined 
impoundments with a liner thickness of three feet resulted in cancer 
risks for arsenic of up to 7 x 10-6 and noncancer risks for 
lithium up to an HQ of 2, while management in similarly lined landfills 
resulted in cancer risks for arsenic up to the 1 x 10-5. The 
larger increase in arsenic risks for unlined impoundments above those 
for clay-lined impoundments (1 x 10-5 vs. 7 x 
10-6) compared to unlined and clay-lined landfills (2 x 
10-5 vs. 1 x 10-5) is because the layer of low 
conductivity clay counteracts the hydraulic head in impoundments that 
would otherwise freely drive greater volumes of leachate into the 
subsurface.\17\ In contrast, leachate generation in both types of 
landfills is limited far more by the rate of precipitation. As a 
result, EPA further considered how reducing the modeled clay liner 
thickness of impoundments to the minimum allowable standard of two feet 
would affect arsenic risk and found it would increase to as high as 2 x 
10-5.
---------------------------------------------------------------------------

    \17\ The somewhat higher risks identified for clay-lined 
landfills compared to similarly lined impoundments are likely 
related to site-specific conditions, such as where in the country 
these units are located.
---------------------------------------------------------------------------

    The second practice evaluated was the management of wastes with an 
extreme pH. In particular, empirical porewater data revealed that co-
management of CCR with other wastes in surface impoundments had the 
potential to result in a highly acidic pH, cancer risks for arsenic up 
to 1 x 10-3, and noncancer risks for cobalt and mercury up 
to an HQ of 13 and 5, respectively. Laboratory leaching test data also 
indicated that highly acidic and basic CCR wastes have the potential to 
leach similarly high arsenic concentrations, up to an order of 
magnitude higher than under more neutral conditions. Only a small 
number of previous landfill model runs considered acidic conditions 
based on the information available about conditions in active units; 
identified risks for these units were driven by more basic conditions. 
Thus, to the extent that at conditions at either extreme of the pH 
scale are more prevalent than previously estimated, it is likely that 
overall risks from disposal in both surface impoundments and landfills 
would be even higher than modeled.
    EPA acknowledged in the 2014 Risk Assessment that there were some 
additional management practices that may result in higher risk at 
individual sites, but that could not be quantitatively modeled with the 
data available at the time. One specific example provided was of CCR 
disposal below the water table. EPA was unable to quantitatively model 
the associated risks as there was little data on how common this 
practice was or the extent to which it could affect groundwater 
chemistry. Because EPA could not quantitatively model these management 
practices (and because the Agency had no information to indicate that 
it was a current, widespread management practice), EPA noted only that, 
based on its review of damage cases, the damage from the placement of 
CCR in sand and

[[Page 32010]]

gravel pits was almost always associated with CCR being placed in 
contact with water, which indicated that the placement of CCR in 
contact with water can lead to higher risks than from dry disposal. 80 
FR 21352, April 17, 2015. EPA further explained that ``in this 
situation, the sorption that occurs in the unsaturated zone of the risk 
assessment model does not occur in the field. This and other site-
specific risk factors could lead to additional contamination beyond 
what was modeled nationwide.'' 2014 Risk Assessment at pages 5-48. As a 
consequence, EPA specifically included sand and gravel pits that 
received CCR in the definition of CCR landfills covered by the 
regulations. 80 FR 21354.
    EPA believes the groundwater data that have since been collected 
from monitoring systems installed around surface impoundments and 
landfills generally validates the findings of the 2014 Risk Assessment. 
For example, one limited analysis from 2019 of the groundwater data 
collected as part of the required facility monitoring programs found 
arsenic, molybdenum, and lithium are the constituents most likely to be 
found at concentrations above GWPS in compliance wells.\18\ These data 
broadly confirm that these three constituents, which were identified as 
the primary risk drivers by national-scale modeling, are among those 
found most frequently at elevated levels in site groundwater monitoring 
wells.
---------------------------------------------------------------------------

    \18\ Environmental Integrity Project. 2019. ``Coal's Poisonous 
Legacy: Groundwater Contaminated by Coal Ash Across the U.S.''
---------------------------------------------------------------------------

b. Risks From Historical Disposal Units
    The 2014 Risk Assessment could not directly model risks associated 
with disposal units that had previously closed or become inactive, as 
there was little to no information available about the numbers, 
locations, and characteristics of these historical units. However, 
based on information obtained since 2015, EPA now expects that risks 
posed by the management of CCR in inactive or closed landfills and 
closed surface impoundments at electric utilities could pose risks to 
nearby receptors that are, at a minimum, similar to the levels and 
kinds of risks posed by the currently regulated universe of CCR 
landfills and surface impoundments.
    The unregulated units contain similar types of ash and are located 
on the same facilities, often in close proximity to and sometimes 
underneath the currently regulated units. Therefore, the risks 
associated with historical impoundments and landfills are expected to 
be similar to those modeled for the currently regulated units. Even if 
the historical impoundments have subsequently been at least partially 
dewatered or have undergone some kind of closure, the current absence 
of impounded water does not negate the releases that occurred during 
operation of the unit. In addition, if precipitation can continue to 
freely migrate into the unit, (e.g., because it lacks an effective 
cover system), any leachate generated as a result would be a potential 
ongoing source of contamination, particularly where the unit is already 
leaking or in contact with groundwater. In general, it is expected that 
these historical units have been present for longer than the currently 
operating units at the same sites and so would have had more time to 
leak. As a result, previous and ongoing releases from these historical 
units could potentially be greater and have migrated further from the 
unit than releases from the currently regulated universe of units. 
Furthermore, as described below, there are a number of additional 
reasons to believe that the potential magnitude of releases from 
historical disposal is even greater than EPA modeled in 2014 for the 
currently regulated units.
    First, many facilities have historically disposed of CCR in 
landfills and surface impoundments that lack adequate liner systems. 
Based on surveys conducted by EPA between 2009 and 2010 (hereafter 
``EPA surveys''), EPA estimated in the 2014 Risk Assessment that 33% of 
landfills and 17% of impoundments had composite liners.\19\ It has 
since become clear that even fewer units are lined. EPA's review of 
liner demonstration documents posted on facilities' CCR websites found 
that only 8% of landfills and 6% of impoundments in operation attest to 
having a standard or alternative composite liner. It is unlikely that 
historical units were lined at higher rates, particularly those 
constructed prior to the promulgation of minimum standards for disposal 
in RCRA subtitle D landfills in 1991. See, 40 CFR part 257, subpart A 
and part 258. Most of the coal-fired utilities in the United States 
were constructed before 1990.\20\ Therefore, the risks associated with 
historical disposal units are likely to be at least as high as 2 x 
10-5 based on the estimates of the risks associated with the 
management of CCR in unlined landfills in the 2014 Risk Assessment. 
This risk estimate for historical landfills would be almost an order of 
magnitude higher than the national-scale risks associated with the 
management of CCR in landfills modeled in the 2014 Risk Assessment. 
This risk estimate would also be twice the level of risk that EPA 
typically considers for regulation and is the same level of risk as 
those associated with the clay-lined CCR surface impoundments that the 
D.C. Circuit required to close.
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    \19\ U.S. EPA. 2014. ``Human and Ecological Risk Assessment of 
Coal Combustion Residuals.'' RIN 2050-AE81. Office of Solid Waste 
and Emergency Response. Washington, DC. December.
    \20\ United Stated Energy Information Administration. 2017. 
``Most Coal Plants in the United States were Built Before 1990.'' 
Accessed online at: https://www.eia.gov/todayinenergy/detail.php?id=30812.
---------------------------------------------------------------------------

    Second, some facilities conduct coal preparation activities prior 
to combustion. These activities may include coal handling by conveyor 
systems, coal washing for removing mineral matter, and coal ``sizing'' 
to reduce the average particle size of coal. The wastes generated from 
coal preparation activities are collectively referred to as ``coal 
refuse.'' Some facilities have been known to dispose of coal refuse 
together with CCR. Such co-disposal can have a pronounced effect on the 
leaching behavior of CCR because of the potential for the refuse to 
make the overall waste pH far more acidic. Available Leaching 
Environmental Assessment Framework (LEAF) leaching data considered in 
the 2014 Risk Assessment show that multiple Appendix IV constituents 
are most soluble at an acidic pH and thus able to leak at higher rates. 
As a result, EPA found modeled risks were often highest when CCR was 
disposed with coal refuse. For example, the modeled cancer risks for 
the co-disposal of ash and coal refuse (pH 1.7-8.2) in surface 
impoundments ranged between 1 x 10-3 for trivalent arsenic 
to 4 x 10-4 for pentavalent arsenic. Non-cancer risks were 
similarly high, ranging between and an HQ of 13 for cobalt and HQ of 14 
for pentavalent arsenic to 26 for trivalent arsenic, based on the 
ingestion of contaminated drinking water.
    The practice has declined over time. A survey conducted by Electric 
Power Research Institute (EPRI) in 1995 showed 34 percent of unlined 
landfills and 68 percent of unlined surface impoundments actively 
managed CCR with coal refuse.\21\ In contrast, EPA surveys indicated 
that, by 2014 this management practice had declined to around 5% of all 
operating units. EPA's 2014 national-scale modeling was based on the 5% 
reported in the EPA surveys, and as a consequence, this practice had 
minimal influence on the overall

[[Page 32011]]

nationwide risk estimates in the 2014 Risk Assessment. However, it is 
clear from the EPRI data that management of CCR with coal refuse used 
to be far more common. Therefore, the risks associated with historical 
disposal units, such as closed units or inactive landfills, are likely 
to be higher than the national-scale risks reported in the 2014 Risk 
Assessment.
---------------------------------------------------------------------------

    \21\ EPRI. 1997. ``Coal Combustion By-Products and Low-Volume 
Wastes Comanagement Survey.'' Palo Alto, CA. June.
---------------------------------------------------------------------------

    Finally, it is known that facilities have disposed of CCR in units 
that either have been constructed beneath the water table or have since 
become inundated with groundwater. EPA's review of the location 
restriction demonstrations posted on facilities' CCR websites found 
that approximately 31% of operating impoundments have waste below the 
water table; similar data are not available for landfills. EPA 
previously identified disposal below the water table as a management 
practice that could result in higher risks than those modeled in the 
2014 Risk Assessment. Since promulgation of the 2015 CCR Rule, it has 
become apparent that the practice of disposing of CCR below the water 
table is more common than previously understood. Given that most 
historical landfills and impoundments are located on the same sites as 
the currently operating units, and are therefore located in the same 
hydrogeologic environments, there is good reason to believe that such 
units at some of these sites were constructed in contact with the water 
table or have since become inundated with groundwater.
    The greater prevalence of this management practice has significant 
implications for the risks associated with CCRMU. First, a CCR landfill 
saturated with water during operation, either continuously or 
intermittently, would have behaved more like an operating CCR surface 
impoundment, even though such a unit would not have the hydraulic head 
from ponded water present in an operating impoundment. The hydraulic 
head from the ponded water in an operating impoundment unit allows for 
continual leaching of contaminants from the CCR and drives the 
resulting leachate into underlying soils and potentially into the 
underlying aquifer. However, where any part of the unit is actually 
constructed below the water table, the conditions caused by the 
continuous saturation of the CCR by the groundwater flowing in and out 
of the unit allow the contaminants in the unit to continuously leach 
directly into the nearby ground and surface waters, even without any 
downward pressure from hydraulic head pushing leachate out of the unit. 
Second, for the same reasons, closed units and inactive landfills that 
continue to be saturated by groundwater will continue to present these 
same risks, even though no additional CCR will have been added to the 
unit.
    Further there are several ways in which disposal below the water 
table can result in higher risks than EPA originally estimated in 2014. 
One of these is that it has the potential to alter groundwater 
chemistry in ways that increase either the solubility or mobility of 
CCR contaminants. This is due to the residual, unburnt organic matter 
in CCR serving as a carbon source (i.e., substrate, electron donor) for 
bacteria in the soil. Bacteria preferentially use any dissolved oxygen 
(O2) for oxidation of organic matter (i.e., electron 
transfer from the organic matter to oxygen) because this yields the 
greatest energy returns for the bacteria. With a sufficient source of 
biodegradable organic matter, bacterial consumption of oxygen can 
outpace replenishment of dissolved oxygen that occurs through diffusion 
from the atmosphere and infiltration of precipitation. Depletion of 
oxygen is more likely to occur in saturated soils because the constant 
presence of water allows biological activity to proceed unimpeded by 
periods of drying, the relatively slow flow rate of groundwater does 
not transport dissolved oxygen from the upgradient side of the unit 
fast enough to outpace consumption across the footprint of the unit, 
and sustained saturation of the soil limits oxygen exchange with the 
atmosphere. In the absence of oxygen, bacteria will instead use 
nitrate, manganese, iron, sulfate, and other compounds for reduction of 
organic matter (i.e., electron transfer to organic matter from other 
compounds). Such reducing conditions will not affect all constituents 
equally, serving to mobilize some and immobilize others. However, 
reducing conditions can mobilize arsenic, the primary source of risks 
identified in the 2014 Risk Assessment, in two primary ways. First, the 
transformation of iron, sulfur, and other minerals in the ash and soil 
can free arsenic that was either complexed with or sorbed onto these 
minerals. Second, reducing conditions can change the dominant oxidation 
state of arsenic (i.e., how many electrons the atom has gained or lost 
in its present state), resulting in a more mobile form that is not 
retained as well on the soil surface.
    Research conducted since the 2014 Risk Assessment has better 
documented the potential effects of disposal below the water table on 
leakage from CCR units. Studies published in 2022 examined, among other 
things, the degree to which environmental conditions can differ within 
the same closed impoundment, both above and below the water 
table.22 23 Specifically, arsenic concentrations measured in 
the water intermingled with CCR collected from beneath the water table 
were as high as 4,100 [micro]g/L due to the presence of reducing 
conditions and a near neutral pH of 8. That concentration is 
substantially higher than 20 [micro]g/L, measured from the same ash 
with LEAF Method 1313 at a similar pH, or 780 [micro]g/L, which is the 
90th percentile of all impoundment porewater measurements previously 
compiled by EPA. Altogether this indicates that the 2014 Risk 
Assessment, which relied on data from these two sources, may have 
underestimated the potential magnitude of leakage from CCR units under 
reducing conditions. Data collected using LEAF methods, like all 
standardized leaching tests, tend to reflect oxidizing conditions due 
to contact between the sample and the atmosphere during sample 
collection and laboratory analysis. It has since been recognized that 
further analysis of leachate data with geochemical speciation models 
may be warranted when field conditions diverge from those present in 
the laboratory setting (e.g., reducing conditions).\24\ Data from the 
Agency's empirical porewater dataset may reflect reducing conditions to 
some degree because the ash in these units remains saturated. Yet, 
there are reasons to believe that reducing conditions would not be as 
common or extreme in operating impoundments. Operating impoundments are 
open to the air, frequently have new water sluiced into them, and may 
be periodically dredged. These conditions introduce oxygen into the 
impoundment far faster and more frequently than a closed and capped 
impoundment. For all these reasons, it is likely that long-term 
disposal of CCR below the groundwater table, whether in a closed or 
partially dewatered impoundment, a closed or inactive landfill, or 
other method of management, can pose risks

[[Page 32012]]

similar to or even greater than previously modeled for operating 
surface impoundments.
---------------------------------------------------------------------------

    \22\ Wang, X., A.C. Garrabrants, Z. Chen, H.A. van der Sloot, 
K.G. Brown, Q. Qiu, R.C. Delapp, B. Hensel, and D.S. Kosson. 2022. 
``The Influence of Redox Conditions on Aqueous-Solid Partitioning of 
Arsenic and Selenium in a Closed Coal Ash Impoundment.'' Journal of 
Hazardous Materials. 428:128255.
    \23\ Wang, X, H.A. van der Sloot, K.G. Brown, A.C. Garrabrants, 
Z. Chen, B. Hensel, and D.S. Kosson. 2022. ``Application and 
Uncertainty of a Geochemical Speciation Model for Predicting 
Oxyanion Leaching from Coal Fly Ash under Different Controlling 
Mechanisms.'' Journal of Hazardous Materials. 438:129518.
    \24\ U.S. EPA. 2019. ``Leaching Environmental Assessment 
Framework (LEAF) How-To Guide: Understanding the LEAF Approach and 
How and When to Use It.'' Office of Land and Emergency Management. 
Washington, DC. May.
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    Based on the various lines of evidence outlined above and confirmed 
by the damage cases discussed in the next Unit of the preamble, 
historical disposal practices for CCR diverge from current practices in 
several material ways. Each of these practices individually have the 
potential to result in risks even higher than those previously modeled 
for the currently operating universe of CCR units, and a combination of 
these practices could push risks even higher.
2. Damage Cases
    EPA has a long history of considering damage cases in its 
regulatory decisions under RCRA. RCRA specifically directs EPA, when 
making a Regulatory Determination for CCR, to consider ``documented 
cases in which danger to human health and the environment from surface 
run-off or leachate has been proved,'' demonstrating that such 
information is to carry great weight in decisions of whether and how to 
regulate such wastes. 42 U.S.C. 6982(n)(4). See also 42 U.S.C. 
6982(n)(3). In addition, damage cases are among the criteria EPA must 
consider under its regulations for determining whether to list a waste 
as a ``hazardous waste.'' See 40 CFR 261.11(a)(3)(ix). EPA also relied 
on damage cases to develop the specific requirements for CCR in part 
257, subpart D. See, 80 FR 21452-21459.
    Damage cases generally provide direct evidence of both the extent 
and nature of the potential risks to human health and the environment 
that have resulted from actual waste management practice. For example, 
in the 2015 CCR Rule, EPA relied on damage cases to identify actual 
management practices that resulted in harm above and beyond that 
already identified through modeling. Based on the damage cases, EPA 
identified several additional constituents (antimony, barium, 
beryllium, chromium, selenium, and lead) that were added to the 
Appendix IV list for groundwater monitoring. For CCRMU, EPA is relying 
on the damage cases to further support the results of the modeling 
discussed in the preceding Unit of this preamble and to better 
understand the characteristics of the sites and units, as well as the 
management practices, in order to develop appropriate requirements.
a. Data Sources Reviewed
    In response to the ANPRM, EPA received comments that contained 
information stating that groundwater contamination was occurring at 
many sites from federally unregulated units such as inactive landfills, 
closed landfills, and fill. Additionally, EPA received comments, 
reports, and data from states, nongovernmental organizations, citizen 
groups, and other stakeholders, regarding groundwater contamination 
from currently unregulated CCR sources. EPA also reviewed comments 
received on the ANPRM. One commenter, Earthjustice et al., said:

    EPA only regulates CCR landfills that were active after October 
2015, which leaves hundreds of coal ash landfills [to] escape all 
closure, source control, and remediation requirements. Commenters 
now know that these coal ash landfills are currently causing serious 
groundwater contamination. The analysis of the Ashtracker \25\ data 
presented in these comments shows that the vast majority of CCR 
landfills threaten human health and the environment. Data indicate 
that distinctions based on landfill type or the date that the unit 
ceased operation are effectively meaningless from a risk 
perspective. Unless EPA addresses the threats posed by inactive 
landfills, the CCR Rule will continue to fall short of the RCRA 
protectiveness standard. Serious and ongoing harm caused by coal ash 
will never be resolved, until EPA applies its regulatory oversight 
to these toxic open dumps.
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    \25\ Ashtracker provides public access to industry-reported data 
from state and company records about groundwater contamination at 
coal ash dumps. It can be accessed at https://www.ashtracker.org.

    Earthjustice et al., also provided a list of 47 potential inactive 
landfills \26\ identified in EPA Information Request Responses from 
Electric Utilities,\27\ EPA Human and Ecological Risk Assessment of 
Coal Combustion Residuals (Dec. 2014),\28\ and U.S. Energy Information 
Administration (EIA) Monthly Electric Generator Inventory (``EIA 
860M'').\29\
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    \26\ EPA-HQ-OLEM-2020-0107-0073.
    \27\ Database Results (Excel) 04-12-12 at https://archive.epa.gov/epawaste/nonhaz/industrial/special/fossil/web/html/index-3.html and Summary Table for Impoundment Reports (.xls)--July 
31, 2014, at https://archive.epa.gov/epawaste/nonhaz/industrial/special/fossil/web/html/index-4.html. Available at EPA-HQ-OLEM-2020-
0107-0003.
    \28\ U.S. EPA. 2014. ``Human and Ecological Risk Assessment of 
Coal Combustion Residuals.'' RIN 2050-AE81. Office of Solid Waste 
and Emergency Response. Washington, DC. December. Docket ID No. EPA-
HQ-RCRA-2009-0640-11993.
    \29\ https://www.eia.gov/electricity/data/eia860m/.
---------------------------------------------------------------------------

    EPA reviewed these data and found the information used to support 
the 2015 CCR Rule included EIA data that estimated which power plants 
disposed of CCR either wet (in CCR surface impoundments) or dry (in CCR 
landfills) to estimate the number of CCR units on-site. These 2014 
estimates of CCR units were not always verified at the time, nor did 
the data contain actual unit names or exact numbers of units on-site, 
nor were the commenters data unit specific with unit names or other 
identifying features. However, since 2016,\30\ the Agency has been 
reviewing the documents posted on facilities' CCR websites for 
compliance with CCR regulations. Specifically, EPA has reviewed 
groundwater monitoring reports, assessment of corrective measures 
reports, corrective measures progress reports, remedy selection 
reports, history of construction reports, closure plans and reports, 
and fugitive dust control plans for facilities with CCR websites from 
2018, 2019, 2020, and 2021. Through the review of information posted by 
facilities on CCR websites and implementation of the 2015 CCR Rule, EPA 
has better estimates of the different types of units at regulated 
facilities. Some of the differences between the 2014 Risk Assessment 
data, 2014 Regulatory Impact Analysis (RIA), and the current known 
universe of regulated facilities are due to differences in reporting 
between cells versus units, general assumptions about the number of 
wet/dry units at a facility, changes in unit names over time due to 
different waste management practices, and inclusion of storage 
impoundments that were later determined to not contain CCR and 
therefore were not CCR surface impoundments.
---------------------------------------------------------------------------

    \30\ In December 2016, the Water Infrastructure Improvements for 
the Nation (WIIN) Act gave EPA enforcement authority under RCRA 
sections 3007 and 3008 for the CCR regulations. See RCRA section 
4005(d).
---------------------------------------------------------------------------

    Through review of groundwater monitoring and corrective action 
reports, EPA found many instances where the owners or operators of CCR 
facilities claimed that the detection of an SSI or SSL in 
concentrations of Appendix III or IV constituents in groundwater came 
from a CCRMU rather than the monitored regulated CCR unit. Whenever a 
facility determines that there is an SSI over background levels for one 
or more of the constituents in Appendix III at a monitoring well at the 
downgradient waste boundary, the regulations allow the facility an 
opportunity to complete an alternative source demonstration (ASD) 
showing that a source other than the unit (i.e., an alternative source) 
was the cause of the SSI. Section 257.94(e)(2). The regulations provide 
a similar opportunity whenever assessment monitoring results indicate 
that an SSL exceeding the GWPS has been detected at a downgradient well 
for any of the Appendix IV constituents. 40 CFR 257.95(g)(3). If a 
successful ASD for an SSL is not completed within 90 days, corrective 
action must be initiated.

[[Page 32013]]

Specifically, EPA found in reviewing groundwater monitoring and 
corrective action reports that 42 ASDs or assessments of corrective 
measures (ACMs) concluded that a federally unregulated CCR source was 
responsible for the SSI or SSL. In Unit IV.B.2.b and c of this preamble 
are several examples (i.e., damage cases) where owners or operators of 
CCR facilities claimed that an SSI or SSL is attributable to a CCR 
source rather than the federally regulated CCR unit.
    In addition to reviewing the groundwater monitoring and corrective 
action reports, EPA also reviewed the history of construction reports, 
closure plans and reports, and fugitive dust control plans for 
facilities with CCR websites from 2018, 2019, 2020, and 2021. These 
documents contained either site maps, which identified currently 
regulated units, and in some cases, inactive or closed units at the 
facility, or narrative discussions of the site history, which included 
identification of where CCR were previously disposed or managed at the 
facility. Through this review, EPA found 65 references to CCR that are 
managed or disposed outside federally regulated CCR units; however, EPA 
was not able to find additional information about these units including 
whether groundwater monitoring has been conducted.
    Given the available data about CCR facilities, the Agency reviewed 
the records for evidence of inactive landfills at active CCR facilities 
and inactive CCR facilities. EPA reviewed the available data and found 
clear, written documentation of about 34 inactive or closed CCR 
landfills at 22 CCR facilities. In addition, EPA evaluated those 
verified inactive or closed CCR landfills and found evidence from ASD 
reviews that eight landfills were identified as contaminating 
groundwater. Some of the landfills are adjacent to a federally 
regulated CCR unit and some are below federally regulated CCR units but 
are not considered part of the regulated unit. This is the available 
information that the Agency has regarding inactive CCR landfills and 
EPA has no information to suggest a different situation regarding 
inactive CCR landfills.
    After reviewing all of this information, EPA identified a total of 
134 areas at 82 active facilities \31\ where CCR is being managed, but 
which remain exempt under existing federal CCR regulations. These areas 
include inactive CCR landfills, closed CCR landfills, closed CCR 
surface impoundments, and other solid waste management areas of CCR. 
Through further investigation, EPA found 42 federally unregulated units 
with documentation that the units are potentially contaminating 
groundwater. Of those, EPA found evidence that eight were associated 
with closed CCR landfills, one related to an inactive CCR landfill, 22 
pertained to closed CCR surface impoundments, three involved CCR 
disposed below the regulated CCR unit, and eight related to CCR 
disposed or managed in other solid waste management areas. A subset of 
examples of these 42 federally unregulated units are briefly summarized 
below; first for facilities that attributed an SSL associated with a 
federally regulated landfill or impoundment to the federally 
unregulated unit and second where SSIs are attributed to a federally 
unregulated unit. Although some of these units are being regulated or 
addressed by states, it does not negate the need to expand the federal 
CCR regulations to address contamination and potential risks from CCRMU 
across the nation.
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    \31\ This information can be found in the document titled 
``Potential CCR Management Units'' in the docket for this action.
---------------------------------------------------------------------------

b. Examples of CCRMU With Identified SSLs
    Under the existing CCR regulations, when a facility determines 
there is an SSL for one or more Appendix IV constituents and completes 
a successful ASD showing that a source other than the regulated unit is 
the cause of the SSL(s), the facility is not required to initiate 
corrective action for that particular constituent. Through ASD reviews, 
EPA identified several areas at active facilities where CCR was managed 
outside of a regulated unit and was identified as a source of one or 
more Appendix IV SSL(s). The following facilities are examples of 
situations in which potential CCRMU have been identified as the source 
of an SSL and demonstrate the need to expand the federal CCR 
regulations as EPA is proposing in this preamble.
James H Campbell Power Plant, West Olive, Michigan
    The JH Campbell Power Plant, owned and operated by Consumers Energy 
Company, is located within a mile of Lake Michigan. The facility has 
five regulated CCR units, including three CCR surface impoundments 
(Pond A, Bottom Ash Ponds 1-2, and Bottom Ash Pond 3) and two CCR 
landfills. The ``wet ash ponds area'' is approximately 267 acres and is 
bounded by perimeter dikes with a system of internal dikes separating 
the individual ash ponds. In addition to the five regulated CCR units, 
there are at least seven other unregulated, unlined ``closed'' 
impoundments \32\ that ceased placement of waste prior to October 19, 
2015, do not have an engineered cap nor vegetative cap, and have a 
closure plan that was approved by the State. Based on the groundwater 
monitoring report reviews, there were SSIs over background at many 
wells at all units and some had an SSL for arsenic and selenium. At 
Pond A, which closed with waste in place in 2019, there are SSIs for 
boron and sulfate, and SSLs were identified for arsenic (13 [micro]g/L 
[MCL of 10 [micro]g/L]) and selenium \33\ (143 [micro]g/L [MCL of 50 
[micro]g/L]) for which an assessment of corrective measures was 
completed, and the selected remedy is source removal and final cover as 
the primary corrective action. In the 2021 Annual Groundwater 
Monitoring and Corrective Action Report posted in January 2022, 
Consumers Energy concluded there was an ASD for Pond A and said, 
``Increases in Appendix III constituents (e.g., boron) and direct 
exceedances of the selenium GWPS in JHC-MW-15011, JHC-MW-15010, JHC-MW-
15009, and JHC-MW-15008R that have not yet resulted in a statistically 
significant exceedance suggest a detectable influence from the 
immediately adjacent, upgradient, closed, pre-existing CCR units on-
site. The closed, preexisting units are not regulated under the RCRA 
CCR Rule, but remedial action is being taken under Consent Agreement 
WMRPD No. 115-01-2018. A [remedial action plan] for these units was 
submitted to [Michigan's Department of Environment, Great Lakes, and 
Energy] on September 30, 2021.'' During the 2021 groundwater monitoring 
period for Bottom Ash Ponds 1-2, which closed by removal in 2018, SSIs 
were identified for boron, calcium, chloride, pH, sulfate, and total 
dissolved solids (TDS); also, one SSL was identified for arsenic (38 
[micro]g/L [MCL of 10 [micro]g/L]).\34\ An assessment of corrective 
measures has been completed for the CCR unit and the primary selected 
remedy is source removal and final cover. Consumers Energy also said in 
the 2022 semiannual

[[Page 32014]]

progress report that the facility is reevaluating the groundwater 
``monitoring system for [Bottom Ash] Ponds 1-2 to more accurately 
account for the influence from the closed, pre-existing units.''
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    \32\ These ``closed'' impoundments (Pond B, Pond C, Pond D, Pond 
F, Pond G (G1 and G2), Pond H, and Pond K) are listed in a figure on 
page 12 of the 2021 Annual Groundwater Monitoring and Corrective 
Action Report, JH Campbell Power Plant Pond A, January 2022, 
Prepared for Consumer's Energy.
    \33\ JH Campbell Semiannual Progress Report--Selection of 
Remedy, Ponds 1-2 North and 1-2 South, and Pond A, July 30, 2022. 
Pages 3-4.
    \34\ Annual Groundwater Monitoring and Corrective Action Report, 
JH Campbell Power Plant Ponds 1-2 North and 1-2 South, January 2022, 
Prepared for Consumers Energy. Page 23.
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New Castle Generating Station, Pennsylvania
    GenOn Power Midwest LP (GenOn) operates the New Castle Generating 
Station located in West Pittsburg, Pennsylvania. The New Castle 
Generating Station has two CCR units subject to the regulations--an 
impoundment (North Bottom Ash Pond) and a landfill (New Castle Plant 
Ash Landfill). Each of these CCR units has relevance to this proposal 
due to other unregulated disposal units located adjacent to the 
regulated CCR units.
    The North Bottom Ash Pond was used for the management of bottom ash 
until 2016 when the facility transitioned from coal to natural gas. 
After the transition to natural gas, GenOn initiated closure of the 
North Bottom Ash Pond by removing all waste from the impoundment. 
Closure of the impoundment was certified in 2019.\35\ Groundwater 
monitoring associated with the impoundment while the unit was operating 
detected arsenic at SSL above the GWPS in all downgradient monitoring 
wells.\36\ In accordance with the procedures in the regulations for CCR 
units in 40 CFR 257.94(e)(2), GenOn determined that an alternative 
source was responsible for these SSLs of arsenic. Specifically, the ASD 
found that a 120-acre unlined CCR surface impoundment located 
immediately adjacent to the North Bottom Ash Pond was responsible for 
the arsenic concentrations in the downgradient monitoring wells.\37\ 
According to the 2019 Annual Report prepared by GenOn, there were SSLs 
for arsenic (0.087 mg/L [MCL of 10 [micro]g/L]) in the downgradient 
monitoring wells.\38\ Consequently, because the SSLs of arsenic were 
attributed to another source (i.e., a former unlined CCR surface 
impoundment), GenOn concluded it was not required to remediate the 
arsenic contamination under the federal CCR regulations.
---------------------------------------------------------------------------

    \35\ CCR Compliance, Closure Certification Report, Closure by 
Removal, New Castle North Bottom Ash Pond. June 2019.
    \36\ Id. At 5.
    \37\ Id.
    \38\ CCR Compliance, Groundwater Monitoring and Corrective 
Action Annual Report, New Castle North Ash Pond and Ash Landfill. 
January 2020.
---------------------------------------------------------------------------

    GenOn also determined that there were SSIs above background levels 
for multiple analytes at the New Castle Plant Ash Landfill (Ash 
Landfill), which is the other regulated CCR unit at the New Castle 
Generating Station. In its most recent annual groundwater monitoring 
report in 2022, GenOn reported SSIs for boron, calcium, fluoride, 
sulfate, and total dissolved solids.\39\ GenOn determined that an 
alternative source was responsible for these analyte increases, 
specifically pointing to an ``underlying historic ash impoundment and 
other closed stages of the landfill.'' \40\ Prior to development of the 
60-acre Ash Landfill, CCR was disposed in an impoundment from 
approximately 1939 to 1978.\41\ After the impoundment was dewatered in 
1978, dry CCR was disposed in this area in several stages of CCR 
placement up until the time Ash Landfill began operation. Since 2018, 
GenOn has attributed SSIs for boron, calcium, fluoride, sulfate, and 
TDS to this historic disposal of CCR.
---------------------------------------------------------------------------

    \39\ CCR Compliance, Groundwater Monitoring and Corrective 
Action Annual Report, New Castle Ash Landfill. December 2022.
    \40\ Id. At 3.
    \41\ New Castle Plant Ash Landfill--Annual CCR Unit Inspection 
Report. January 16, 2018.
---------------------------------------------------------------------------

Huntington Power Plant, Utah
    The Huntington Power Plant in Huntington, Utah is owned and 
operated by PacifiCorp and has one regulated unit, the Huntington CCR 
Landfill. While conducting the required groundwater monitoring for the 
Huntington CCR Landfill, there were SSLs for chromium, cobalt, lithium, 
molybdenum, selenium, fluoride, and arsenic, so the owner and operator 
conducted assessment of corrective measures. There is also a former 
combustion waste landfill called the Old Landfill, which is located 
northwest of the regulated Huntington CCR Landfill. The ACM report \42\ 
assumes the SSLs are the result of groundwater interactions with both 
the Huntington CCR Landfill and the Old Landfill. Both landfills have 
stormwater run-on from the area surrounding the landfill. This run-on 
is routed around the landfills via diversion ditches and run-off from 
the landfills itself is collected and retained in a sediment basin 
north of the Huntington CCR Landfill. The facility is implementing a 
remedy to address releases only from the regulated CCR Huntington 
Landfill, but the remedy selection report \43\ does not appear to 
address releases from the Old Landfill.
---------------------------------------------------------------------------

    \42\ Corrective Measures Assessment CCR Landfill--Huntington 
Power Plant Huntington, Utah. May 2019.
    \43\ Remedy Selection Report CCR Landfill--Huntington Power 
Plant, Huntington, Utah. August 2020.
---------------------------------------------------------------------------

J.B. Sims, Grand Haven, Michigan
    The J.B. Sims Generating Station, owned and operated by Grand Haven 
Board of Light and Power, is located on Harbor Island, north of Grand 
Haven, Michigan. Harbor Island is bound to the north, east, and west by 
the Grand River and to the south by the South Channel, tributaries of 
Lake Michigan. The facility has two federally regulated CCR units (Unit 
1 & 2 and Unit 3), both of which are inactive, unlined surface 
impoundments. Unit 1 & 2 is approximately 1.2 acres and includes areas 
where, prior to October 19, 2015, CCR was placed in unlined 
impoundments and used as fill in low-lying areas of adjacent wetlands. 
Unit 3 is approximately 0.5 acres and was built on top of historically 
placed CCR. The boundary of Unit 1 & 2 was updated in an agreement with 
EPA and the State in January 2021,\44\ to include an area that received 
CCR prior to 1978. Therefore, the groundwater monitoring network and 
closure plan are currently being updated to reflect the new boundary 
and better address contamination from historical CCR across the 
units.\45\ Additionally, in March 2022, the State issued an enforcement 
notice \46\ to J.B. Sims citing inadequate groundwater monitoring and 
failure to address all areas where CCR were managed (e.g., stored, 
placed) prior to disposal during the unit's operation. As such, the 
facility is considering expanding Unit 3's groundwater monitoring 
network. The units are often partially flooded, and groundwater 
elevations and flow direction are influenced by precipitation and water 
levels in the Grand River and the South Channel.
---------------------------------------------------------------------------

    \44\ The meeting between Grand Haven Board of Light and Power, 
the state, and EPA during which the new boundaries for Unit 1 & 2 
were agreed to is discussed on page 3 (PDF page 10) of the 2021 
Annual Groundwater Monitoring & Corrective Action Report by Golder 
Associates. January 28, 2022.
    \45\ Letter to Grand Haven Board of Light and Power-Update To 
The October 14, 2019 J.B. Sims Generating Station Inactive Units \1/
2\ Impoundment And Unit 3 Closure Plan--Interim Conditions For 
Closure. October 22, 2021.
    \46\ The State of Michigan, Department of Environment, Great 
Lakes, and Energy (EGLE) issued an enforcement notice via email 
March 22, 2022, to Grand Haven Board of Light and Power, J.B. Sims.
---------------------------------------------------------------------------

    Based on groundwater monitoring report reviews, both units have had 
SSIs and SSLs since groundwater monitoring was initiated in 2017. 
During 2021, both Unit 1 & 2 and Unit 3 had SSIs for all Appendix III 
constituents and SSLs for arsenic (98 [micro]g/L [MCL is 10 [micro]g/
L]), chromium (270 [micro]g/l [MCL is 100 [micro]g/L]), cobalt (22 
[micro]g/l [GWPS is 6 [micro]g/L], fluoride (13 mg/L [MCL is 4 mg/L]), 
and

[[Page 32015]]

lithium (2800 [micro]g/L [site-specific GWPS is 59 [micro]g/L]).\47\ In 
December 2020, J.B. Sims submitted an ASD for Unit 3's 2019 SSLs for 
chromium, cobalt, fluoride, lead, and lithium, pointing to the historic 
fill across the island as the source of the SSLs.48 49 
Furthermore, the Fourth Quarterly 2021 Monitoring Report suggested the 
continued SSIs and SSLs at Unit 3 were due to historical CCR fill 
beneath the unit, historical fill outside of Unit 1 & 2, and waste 
historically placed across the site.\50\ However, until the groundwater 
monitoring networks are finalized, the extent of groundwater 
contamination and the source of all contamination cannot be determined. 
The assessment of corrective measures for both units began in February 
2019 and is ongoing, pending finalization of the groundwater monitoring 
networks. Based on groundwater monitoring reports, EPA has found that 
due to the fluctuations in groundwater elevations in response to 
precipitation and nearby surface water levels, portions of the 
facility, including Unit 1 & 2, can be inundated or partially in 
contact with groundwater.
---------------------------------------------------------------------------

    \47\ SSL concentrations can be found in Appendix B (PDF page 
512) of the 2021 Groundwater Monitoring & Corrective Action Report 
prepared by Golder Associates on behalf of Grand Haven.
    \48\ 2020 Alternate Source Demonstration J.B. Sims Generating 
Station--Unit 3 Impoundments Submitted to: Grand Haven Board of 
Light and Power Submitted by Golder Associates Inc. December 28, 
2020.
    \49\ Technical Memorandum to Michigan Department of Environment, 
Great Lakes, and Energy-Unit 3 Impoundments Alternate Source 
Demonstration Response Grand Haven Board Of Light And Power--JB Sims 
Power Generating Station. February 12, 2020.
    \50\ Memorandum to Michigan Department of Environment, Great 
Lakes, and Energy- Fourth Quarter 2021 Monitoring Report, Former JB 
Sims Generating Station, Unit 3 A&B Impoundments--Response to 
Comments. March 8, 2022.
---------------------------------------------------------------------------

c. Examples of CCRMU With Identified SSIs
    Under the existing CCR regulations, when a facility determines 
there is an SSI for one or more Appendix III constituents and completes 
a successful ASD showing that a source other than the regulated unit is 
the cause of the SSI(s), the facility is not required to initiate 
assessment monitoring for that particular constituent. 40 CFR 
257.94(e). Through ASD reviews, EPA identified several areas at active 
facilities where CCR was managed outside of a regulated unit and was 
identified as a source of one or more Appendix III SSI(s). As such, any 
groundwater contamination from these potential CCRMU have not been 
investigated under the existing federal CCR regulations. The following 
facilities are examples of situations in which potential CCRMU have 
been identified as the source of an SSI and demonstrate the need to 
expand the federal CCR regulations as EPA is proposing in this 
preamble.
Reid Gardner Generating Station, Moapa Valley, Nevada
    Reid Gardner Generating Station, owned and operated by NV Energy, 
is located adjacent to the Muddy River and the Moapa Band of Paiutes 
reservation, approximately 45 miles northeast of Las Vegas. Reid 
Gardner has seven regulated CCR units: four unlined inactive surface 
impoundments (Pond 4B-1, Pond 4B-2, Pond 4B-3, and Pond E-1), two 
active unlined surface impoundments (Pond M-5 and Pond M-7), and one 
partially lined landfill (Mesa Landfill). The inactive surface 
impoundments covered 47 acres and were closed by removal in 2017.\51\ 
The inactive surface impoundments were constructed in 2003 (Pond E-1) 
and 2006 (Pond 4B-1, Pond 4B-2, and Pond 4B-3) to replace four of the 
eleven historical unlined evaporation ponds located at the facility 
that made up the evaporation pond complex (Pond 4A, Pond 4B-1, Pond 4B-
2, Pond 4B-3, Pond 4C-1, Pond 4C-2, Pond D, Pond E-1, Pond E-2, Pond F, 
and Pond G).\52\ The evaporation pond complex was built within the 
Muddy River floodplain and used from approximately 1974 until 
approximately 2002 to evaporate CCR and other process wastewaters from 
the facility. The two active surface impoundments (Ponds M-5 and M-7) 
were constructed in 2010 approximately 0.75 miles south of the 
historical evaporation ponds and cover 28 acres. Mesa Landfill was 
constructed and operational prior to the 2015 CCR Rule and has a 
surface area of roughly 252 acres.
---------------------------------------------------------------------------

    \51\ Reid Gardner Generating Station Inactive Coal Combustion 
Residual Surface Impoundments Ponds 4B-1, 4B-2, 4B-3, and E-1 
Closure Certification, April 2019.
    \52\ Construction History, Pond E1, Reid Gardner Generating 
Station. April 11, 2018.
---------------------------------------------------------------------------

    Based on groundwater monitoring report reviews, the inactive 
surface impoundments had no Appendix III SSIs above their established 
background concentrations during the detection monitoring event in 
2019.53 54 55 56 57 58 However, the inactive surface 
impoundments did have Appendix IV constituent concentrations above the 
standard GWPS, including arsenic (2.52 mg/L [MCL is 0.01 mg/L]), 
cadmium (0.0072 mg/L [MCL is 0.005 mg/L]), cobalt (242 [micro]g/L 
[standard GWPS is 6 [micro]g/L]), fluoride (35.4 mg/L [MCL is 4.0 mg/
L]), lithium (27,300 [micro]g/L [standard GWPS is 40 [micro]g/L]), 
molybdenum (6,390 [micro]g/L [standard GWPS is 100 [micro]g/L]), 
selenium (0.204 mg/L [MCL is 0.05 mg/L]), thallium (0.026 mg/L [MCL is 
0.002 mg/L]), and radium 226 & 228 combined (8.02 pCi/L [MCL is 5 pCi/
L]). Ponds M-5 and M-7 and the Mesa Landfill have had SSIs for fluoride 
every year of detection monitoring for which ASDs have been performed 
pointing to natural variation in groundwater 
quality.59 60 61 62 63 64 ASDs were also performed for SSIs 
at Mesa Landfill for pH (2019 and 2021) and turbidity (2020 and 2021) 
that attributed the SSIs to natural variation in groundwater quality. 
Therefore, since ASDs have been performed for all SSIs and the

[[Page 32016]]

active units, Reid Gardner has not moved from detection monitoring to 
assessment monitoring. The facility also claims the historical, co-
located evaporation ponds are the source of groundwater contamination 
in the area and not the CCR-regulated units. Specifically, in the 
closure certification for the inactive surface impoundments, the 
facility points to documentation as far back as the 1980s that describe 
seepage from Pond D, the historical Pond E-1 and E-2, Pond F, and Pond 
G and leakage at an estimated rate of 50 acre-feet/year from Ponds 4C-1 
and 4C-2 and historical Ponds 4B-1, 4B-2, and 4B-3.
---------------------------------------------------------------------------

    \53\ Reid Gardner Generating Station Inactive CCR Surface 
Impoundment E-1. Coal Combustion Residual 209 Annual Groundwater 
Monitoring and Corrective Action Report. July 31, 2019.
    \54\ Reid Gardner Generating Station Inactive CCR Surface 
Impoundments 4B-1, 4B-2, and 4B-3. Coal Combustion Residual 2019 
Annual Groundwater Monitoring and Corrective Action Report. Revision 
1. May 14, 2020.
    \55\ Reid Gardner Generating Station Mesa Impoundments M5 and M7 
Coal Combustion Residual 2019 Annual Groundwater Monitoring and 
Corrective Action Report and Alternate Source Demonstration. January 
31, 2020.
    \56\ Reid Gardner Generating Station Mesa Impoundments M5 and M7 
Coal Combustion Residual 2020 Annual Groundwater Monitoring and 
Corrective Action Report and Alternate Source Demonstration. January 
29, 2021.
    \57\ Reid Gardner Generating Station Mesa Impoundments M5 and M7 
Coal Combustion Residual 2021 Annual Groundwater Monitoring and 
Corrective Action Report and Alternate Source Demonstration. January 
28, 2022.
    \58\ Alternate Source Demonstration and Addendum to the Coal 
Combustion Residual 2017 Annual Groundwater Monitoring and 
Corrective Action Report Reid Gardner Generating Station Mesa CCR 
Surface Impoundments (Ponds M5 and M7). Prepared for NV Energy. 
April 13, 2018.
    \59\ Reid Gardner Generating Station Mesa Landfill Coal 
Combustion Residual 2018 Annual Groundwater Monitoring and 
Corrective Action Report and Alternate Source Demonstration. January 
31, 2019.
    \60\ Reid Gardner Generating Station Mesa Impoundments M5 and M7 
Coal Combustion Residual 2018 Annual Groundwater Monitoring and 
Corrective Action Report and Alternate Source Demonstration. January 
31, 2019.
    \61\ Reid Gardner Generating Station Mesa Landfill Coal 
Combustion Residual 2019 Annual Groundwater Monitoring and 
Corrective Action Report and Alternate Source Demonstration. January 
31, 2020.
    \62\ Reid Gardner Generating Station Mesa Landfill Coal 
Combustion Residual 2020 Annual Groundwater Monitoring and 
Corrective Action Report and Alternate Source Demonstration. January 
31, 2021.
    \63\ Reid Gardner Generating Station Mesa Landfill Coal 
Combustion Residual 2021 Annual Groundwater Monitoring and 
Corrective Action Report and Alternate Source Demonstration. January 
28, 2022.
    \64\ Alternate Source Demonstration and Addendum to the Coal 
Combustion Residual 2017 Annual Groundwater Monitoring and 
Corrective Action Report Reid Gardner Generating Station Mesa 
Landfill. Prepared for NV Energy. April 13, 2018.
---------------------------------------------------------------------------

Cooper Station, Somerset, Kentucky
    Cooper Station is owned and operated by East Kentucky Power 
Cooperative (EKPC) and is located in Somerset, Kentucky. There is one 
CCR landfill on-site, and the disposal area covers 96.32 acres in a 
total State-permitted area of 315.25 acres. Before construction of the 
landfill, CCR was managed in an unlined surface impoundment below the 
current landfill location. The facility conducted an ASD in 2018 for 
boron, calcium, sulfate, and TDS.\65\ Previous analyses indicate that 
karst regions under the historic impoundment may have facilitated the 
release of some contamination. ASD results indicate the regulated CCR 
landfill is not the source of the release since it is lined but did not 
definitively state if the facility determined the unregulated unlined 
surface impoundment beneath the landfill as the alternative source. As 
such, the facility determined that the current CCR landfill remains in 
detection monitoring.
---------------------------------------------------------------------------

    \65\ Annual CCR Groundwater Monitoring & Corrective Action 
Report, Cooper Landfill, January 31, 2019. The ASD is discussed in 
Appendix C of the report.
---------------------------------------------------------------------------

Seminole Electric Cooperative, Florida
    Seminole Electric Cooperative (Seminole) operates the Seminole 
Generating Station located in Palatka, Florida. For CCR that is not 
beneficially used, CCR is disposed at the facility in a landfill 
(Increment One Landfill), which is subject to the CCR regulations. This 
CCR landfill is a double-lined landfill with a leachate collection 
system and, because part of the Increment One Landfill overlaps with 
the side-slope of a former, federally unregulated landfill, the liner 
system also includes a high-density polyethylene geomembrane where the 
two units interface.\66\ Seminole determined there were SSIs above 
background levels for multiple analytes in one or more monitoring wells 
at the downgradient waste boundary in 2018, including SSIs for boron, 
calcium, chloride, sulfate, and TDS. Seminole determined that one or 
more alternative sources were responsible for these analyte increases. 
These sources include former test cells (i.e., areas where CCR was 
placed in the 1980s for purposes of construction evaluations that are 
now located beneath the Increment One Landfill), a former CCR landfill 
adjacent to the Increment One Landfill, and several process water ponds 
next to the Increment One Landfill.\67\ Since 2018, Seminole has 
attributed SSIs for these analytes to these alternative sources and 
therefore, has not moved from detection monitoring to assessment 
monitoring.
---------------------------------------------------------------------------

    \66\ Seminole Generating Station Increment One Landfill Annual 
Groundwater Monitoring and Corrective Action Report. January 31, 
2019.
    \67\ Id. at 20.
---------------------------------------------------------------------------

R.M. Schahfer Generating Station, Indiana
    The R.M. Schahfer Generating Station, owned and operated by 
Northern Indiana Public Service Company, LLC (NIPSCO), has several CCR 
units subject to the regulations, including several CCR impoundments 
and a CCR landfill consisting of multiple cells or phases of operation 
(``Landfill''). The Landfill is of particular relevance to this 
proposal because includes three cells subject to federal CCR 
regulations (Phases V through VII) and four landfill cells that are not 
(Phases I through IV). In the course of conducting the required 
groundwater monitoring for the regulated cells of the Landfill, in 
January 2018, NIPSCO determined that there were SSIs above background 
levels for all seven analytes in Appendix III at one or more monitoring 
wells at the downgradient waste boundary of the regulated CCR units. 
This included SSIs for boron, calcium, chloride, fluoride, pH, sulfate, 
and TDS.\68\ Through procedures laid out in the regulations for 
regulated CCR units in 40 CFR 257.94(e)(2), NIPSCO determined that 
these groundwater SSI impacts were not due to a release from the 
regulated CCR landfill cells, but instead were attributable to another 
source. Specifically, NIPSCO has concluded that ``a release from the 
non-regulated, unlined portions of the landfill, Phases 1 and II, is 
the source of the identified SSIs.'' \69\ Subsequent groundwater 
monitoring of the regulated Landfill cells since 2018 continues to 
identify SSIs and NIPSCO continues to attribute those impacts to 
releases from the unregulated Phase I and II cells.\70\
---------------------------------------------------------------------------

    \68\ 2018 Annual Groundwater Monitoring and Corrective Action 
Report--Landfill Phase V and Phase VI, NIPSCO R.M. Schahfer 
Generating Station. January 31, 2019.
    \69\ Northern Indiana Public Service Company, R.M. Schahfer 
Generating Station, Wheatfield, Indiana, Schahfer Landfill Phase V 
and Phase VI, Alternative Source Demonstration. April 13, 2018. 
Begins on PDF page 20 of the 2018 Annual Groundwater Monitoring and 
Corrective Action Report--Landfill Phase V and Phase VI. April 13, 
2018.
    \70\ 2021 Annual Groundwater Monitoring and Corrective Action 
Report, Landfill Phase V, Phase VI, and Phase VII, NIPSCO LLC R.M. 
Schahfer Generating Station. January 31, 2022.
---------------------------------------------------------------------------

    Landfill Phase I is a 20-acre unlined cell that received CCR (flue 
gas desulfurization materials and fly ash) between 1984 and 1991 and 
subsequently closed with a final cover system in 1999. Phase II of the 
Landfill is an unlined 42-acre cell where flue gas desulfurization 
materials and fly ash were disposed between 1991 to 1998. The Phase II 
cell was closed with a final cover system in 1998. CCR landfills such 
as the Phase I and II cells are not regulated by the existing 
regulations because the cells have not received CCR on or after October 
19, 2015. As a result, NIPSCO has not been required under the existing 
federal CCR regulations to investigate further and remediate as 
necessary groundwater impacts from the unlined Phase I and II cells.
Waukegan Generating Station, Illinois
    An example of CCR used as fill on-site is Midwest Generation's 
Waukegan Generating Station in Waukegan, Illinois. There are two CCR 
surface impoundments named the East Ash Pond and West Ash Pond, which 
were used interchangeably during the facility's operational history and 
have a multi-unit groundwater monitoring system. The East Ash Pond has 
a surface area of 9.8 acres with a storage capacity of 184,000 cubic 
yards. The West Ash Pond has a surface area of 10 acres with a storage 
capacity of 223,000 cubic yards. According to the 2018 Annual 
Groundwater Monitoring and Corrective Action Report, there was 
detection of SSIs over background for Appendix III constituents, 
including pH and sulfate.\71\ An ASD was completed that claimed other 
potential historic sources were the cause of the SSIs. In the 2019 
Annual Groundwater Monitoring and Corrective Action Report, an ASD for 
Appendix III constituents identified calcium and TDS with the same 
claim that other potential historic sources were the cause of the 
SSIs.\72\ The ASDs discuss that the downgradient

[[Page 32017]]

monitoring wells were installed within the berms for the surface 
impoundments that consisted of a ``mixture of fill and beneficially 
reused coal combustion by-product''.73 74 The 2018 ASD also 
notes that a upgradient well, MW-05 which is not a part of the CCR 
groundwater monitoring network, has substantially higher sulfate and 
boron concentrations than the downgradient wells suggesting an 
upgradient source. Furthermore, the 2019 ASD mentions that the 
fluctuating TDS concentrations at downgradient well MW-16 are 
correlated to fluctuations in TDS at MW-05 further suggesting an 
upgradient source. While these ASDs suggest that the sources may be CCR 
within the berms and a upgradient source they do not analyze these 
potential sources to verify the claims. EPA did verify that the boring 
logs for groundwater monitoring wells MW-01 through MW-05 and MW-16 
show they were installed within 11 to 20 feet of CCR in the berms 
surrounding the surface impoundments.\75\ In addition, construction 
drawings in the history of construction show ``existing fill'' or CCR 
was used in the construction of the surface impoundment access ramps 
and underneath the surface impoundments liners.\76\ The facility 
continued to use the ASDs for SSIs in 2020 and 2021, therefore, the 
surface impoundments remain in detection monitoring.
---------------------------------------------------------------------------

    \71\ 2018 Waukegan Generating Station Annual GWMCA Report, 
Appendix B, PDF pg. 100. January 2019.
    \72\ 2019 Waukegan Generating Station Annual GWMCA Report, 
Appendix B, PDF pg. 100. January 2020.
    \73\ 2020 Waukegan Generating Station Annual GWMCA Report. 
January 2021.
    \74\ 2021 Waukegan Generating Station Annual GWMCA Report. 
January 2022.
    \75\ Waukegan boring well logs.
    \76\ October 2016, Waukegan Generating Station History of 
Construction.
---------------------------------------------------------------------------

White Bluff Steam Electric Station, Arkansas
    The White Bluff Steam Electric Station in Redfield, Arkansas is 
owned or operated by Entergy and has three CCR units: two CCR surface 
impoundments (A Recycle Pond/South Pond and B Recycle Pond/North Pond); 
and one CCR landfill (Existing CCR Landfill Cells 1-4). CCR previously 
was disposed in a 20-acre ravine,\77\ which was closed and covered in 
accordance with the original facility State-issued permit. The active 
landfill was then built on top of, and adjacent to, the unlined, closed 
landfill. In 2018, the facility conducted intrawell monitoring of the 
groundwater at the facility and SSIs for pH, calcium, TDS, and boron 
were detected. An ASD was completed and determined that the sources of 
the SSIs were: (1) Releases from portions of the Coal Ash Disposal 
Landfill (CADL) closed before the effective date of the CCR Rule 
(October 19, 2015); (2) Surface water that has come into contact with 
on[hyphen]site CCR and has migrated into the subsurface; and/or (3) 
Natural variation in groundwater quality. Therefore, the landfill 
remains in detection monitoring.
---------------------------------------------------------------------------

    \77\ Entergy Arkansas, LLC White Bluff Steam Electric Station 
Landfill Cells 1-4 2021 Annual Groundwater Monitoring and Corrective 
Action Report. January 31, 2022.
---------------------------------------------------------------------------

3. Summary of CCR Management Unit Proposal
    After considering all of the above data and information, EPA is 
proposing to establish a new category of regulated units that would be 
subject to a set of requirements tailored to the characteristics of 
such units and the risks that they present. EPA is proposing that this 
new category of units, called ``CCR management units'' or CCRMU, would 
consist of CCR surface impoundments and landfills that have closed 
prior to the effective date of the 2015 CCR Rule, inactive CCR 
landfills, and any area at a facility where solid waste management 
involving the past or present placement or receipt of CCR directly on 
the land has or is occurring.
    Further, EPA is proposing to require facilities to conduct a 
facility evaluation to identify and delineate any CCRMU present at the 
facility and document the findings in a report. In addition, EPA is 
proposing to require the facility to ensure that all identified CCRMU 
comply with the existing requirements in part 257 for groundwater 
monitoring, corrective action, closure, and post-closure care 
requirements. These requirements are intended to address the risks 
posed by any existing releases of CCR or CCR constituents to the 
groundwater, regardless of when the CCR was placed in the units and 
prevent future releases. Consistent with the existing CCR regulations, 
owners and operators of CCRMU would also be required to record 
compliance with these requirements in the facility's operating record, 
notify the state of certain actions taken and decisions made, and 
maintain a publicly accessible website on the internet of compliance 
information. The other existing requirements in part 257 are not 
necessary for CCRMU. For example, since CCRMU do not contain sufficient 
liquids to create a hydraulic head or to otherwise cause the conditions 
that might lead to a structural failure, the structural stability 
requirements are unnecessary. Furthermore, EPA is proposing that CCRMU, 
like legacy CCR surface impoundments, must close, and for the same 
reasons that EPA described with respect to legacy CCR surface 
impoundments, the location restrictions and liner design criteria are 
also unnecessary. This proposal would apply to all CCRMU at active CCR 
facilities and at inactive facilities with one or more legacy CCR 
surface impoundments, regardless of how or when the CCR was placed in 
the CCRMU. All of these proposals are discussed in more detail in this 
Unit of the preamble.
    Note that all deadlines herein are framed by reference to the 
effective date of the rule and have been proposed based on an effective 
date that is 6 months from publication of the final rule. The Agency 
has included a document in the docket for this rule that summarizes the 
proposed compliance deadlines.\78\ EPA requests comment on the 
compliance deadlines and the feasibility to meet the proposed 
compliance timeframes for CCRMU.
---------------------------------------------------------------------------

    \78\ Docket item is titled Proposed Compliance Deadlines for 
Legacy CCR Surface Impoundments and CCR Management Units.

       Table 2--Proposed Compliance Timeframes for CCRMU in Months After Effective Date of the Final Rule
----------------------------------------------------------------------------------------------------------------
                                    Proposed compliance timeframes for CCRMU
-----------------------------------------------------------------------------------------------------------------
                                                                Proposed deadline
     40 CFR Part 257, Subpart D          Description of           (months after
            requirement                 requirement to be     effective date of the             Notes
                                            completed              final rule)
----------------------------------------------------------------------------------------------------------------
Internet Posting (Sec.   257.107)..  Establish CCR website.  0.....................  Subsequent requirements:
                                                                                      Facility Evaluation
                                                                                      Report; all recordkeeping.
Facility Evaluation (Sec.   257.75)  Initiate the facility   0.....................  Subsequent requirements:
                                      evaluation.                                     Facility Evaluation
                                                                                      Report.
Facility Evaluation Report (Sec.     Complete the Facility   3.....................  Prerequisite requirements:
 257.75).                             Evaluation Report.                              Facility Evaluation,
                                                                                      Establish CCR website.

[[Page 32018]]

 
GWMCA (Sec.   257.91)..............  Install the             6.....................  Prerequisite requirements:
                                      groundwater                                     Facility Evaluation
                                      monitoring system.                              Report.
                                                                                     Subsequent requirements:
                                                                                      Groundwater sampling and
                                                                                      analysis program; Initiate
                                                                                      detection and assessment
                                                                                      monitoring; Annual GWMCA
                                                                                      report.
GWMCA (Sec.   257.93)..............  Develop the             6.....................  Prerequisite requirements:
                                      groundwater sampling                            Install groundwater
                                      and analysis program.                           monitoring system.
                                                                                     Subsequent requirements:
                                                                                      Initiate detection
                                                                                      monitoring and assessment
                                                                                      monitoring; Annual GWMCA
                                                                                      report.
GWMCA (Sec.   257.90(e))...........  Annual GWMCA report...  January 31 of the year  Prerequisite requirements:
                                                              following GWM system    Install groundwater
                                                              install.                monitoring system;
                                                                                      Groundwater sampling and
                                                                                      analysis plan.
Closure (Sec.   257.102)...........  Prepare written         12....................  Subsequent requirements:
                                      closure plan.                                   Initiate closure.
Post-Closure Care (Sec.   257.104).  Prepare written post-   12....................  Prerequisite requirements:
                                      closure care plan.                              Written closure plan.
Closure and Post-Closure Care (Sec.  Initiate closure......  12....................  Prerequisite requirements:
   257.101).                                                                          Written closure plan.
GWMCA (Sec.  Sec.   257.90-257.95).  Initiate the detection  24....................  Prerequisite requirements:
                                      monitoring and                                  Install groundwater
                                      assessment                                      monitoring system;
                                      monitoring. Begin                               Groundwater sampling and
                                      evaluating the                                  analysis plan.
                                      groundwater
                                      monitoring data for
                                      SSI over background
                                      levels and SSL over
                                      GWPS.
----------------------------------------------------------------------------------------------------------------

4. Applicability and Definitions Related to CCR Management Units
    EPA is proposing to amend Sec.  257.50 by adding a new paragraph 
(j) to specify that subpart D applies to CCRMU. EPA is also proposing 
to add a new definition and revise 11 existing definitions in Sec.  
257.53 to implement the proposed criteria for CCRMU.
a. Definition of CCR Management Unit
    EPA is proposing to define a CCR management unit to capture the 
solid waste management practices that have been demonstrated in the 
risk assessment and the damage cases to have the potential to 
contaminate groundwater. EPA is proposing to define a CCRMU as any area 
of land on which any non-containerized accumulations of CCR are 
received, placed, or otherwise managed, that is not a CCR unit. This 
definition is based on the current definitions of a CCR pile--which is 
currently regulated as a CCR landfill--and of a CCR surface 
impoundment, which both rely on the concept of ``accumulations of 
CCR.'' See, 40 CFR 257.53.
    EPA is proposing that CCRMU would include historical solid waste 
management units such as CCR landfills and surface impoundments that 
closed under then-existing law prior to the effective date of the 2015 
CCR Rule, as well as inactive CCR landfills (including abandoned 
piles). It would also include any other areas where the solid waste 
management of CCR on the ground has occurred, such as structural fill 
sites, CCR placed below currently regulated CCR units, evaporation 
ponds, or secondary or tertiary finishing ponds that have not been 
properly cleaned up, and haul roads made of CCR if the use does not 
meet the definition of beneficial use. All of these examples involve 
the direct placement of CCR on the land, in sufficient quantities to 
raise concern about releases of hazardous constituents, and--in most, 
if not all cases--with no measures in place to effectively limit the 
contact between the CCR and liquids, and subsequent generation and 
release of any leachate.
    EPA recognizes that this is a broad definition, but the Agency does 
not intend that the placement of any amount of CCR would necessarily 
constitute a CCRMU. Accordingly, EPA is proposing that the following 
would not be considered CCRMU: consistent with the current regulations, 
closed or inactive process water ponds, cooling water ponds, wastewater 
treatment ponds, and storm water holding ponds or aeration ponds. These 
units are not designed to hold an accumulation of CCR, and in fact, do 
not generally contain a significant amount of CCR. See, 80 FR 21357. In 
addition, consistent with the existing regulations, neither an area or 
unit at which exclusively non-CCR waste is managed, nor any 
containerized CCR, such as a silo, would be considered CCRMU. See, Id. 
at 21356. Neither of these units present conditions that give rise to 
the risks modeled in EPA's assessment or identified in the damage 
cases.
    For similar reasons, the Agency is proposing that any CCR used in 
roadbed and associated embankments would not be considered CCRMU. As 
EPA explained in the 2015 rule the methods of application are 
sufficiently different from CCR landfills that EPA cannot extrapolate 
from the available risk information to determine whether these 
activities present similar risks. Roadways are subject to engineering 
specifications that generally specify CCR to be placed in a thin layer 
(e.g., six to 12 inches) under a road. The placement under the surface 
of the road limits the degree to which rainwater can influence the 
leaching of the CCR. There are also significant differences between the 
manner in which roadways and landfills can potentially impact 
groundwater. These include the nature of mixing in the media, the 
leaching patterns, and how input infiltration rates are generated. 
First, CCR landfills are typically a homogenously mixed system, and as 
a result, there are no spatial variations of the chemical and physical 
properties of the media (for

[[Page 32019]]

example, bulk density, hydraulic conductivity and contaminant 
concentration). By contrast, roadways are generally constructed of 
several layers with different material properties (heterogeneity). This 
difference affects the hydraulic conductivity of a mass of CCR in a 
landfill, as compared to CCR placed in an embankment. Any potential 
leaching will tend to spread over the length of the embankment, as 
opposed to the leaching in a downward motion that would occur in a 
homogenously filled landfill. Finally, EPA is concerned that 
groundwater monitoring of a road may not be practicable. However, even 
though EPA considers that the available information does not 
demonstrate that use in roadbed present sufficient risk to warrant the 
suite of requirements applicable to CCRMU, that calculus changes in the 
event the CCR in roadbed is contaminating groundwater. Accordingly, EPA 
is proposing that if a facility subsequently determines that the CCR in 
onsite roadbed is contributing to contamination to the aquifer, the 
facility would be required to address the contamination. For example, 
if during an on-going corrective action, a facility identifies the 
roadbed as an additional source of contamination, it would be required 
to address that contamination as part of the ongoing remediation of the 
aquifer. In addition, the measures EPA is proposing to require 
facilities to take would not be expected to identify truly de minimis 
quantities of CCR. As discussed in greater detail in the next section, 
EPA is proposing that facilities would only be required to identify 
accumulations if there are records to confirm the existence of CCRMU or 
visual evidence of CCR placement on the ground.
    As a complement to this definition, EPA is proposing to define the 
term inactive CCR landfill to mean an area of land or an excavation 
that contains CCR but that no longer receives CCR on or after the 
effective date of this final rule and that is not a surface 
impoundment, an underground injection well, a salt dome formation, a 
salt bed formation, an underground or surface coal mine or a cave. For 
purposes of this subpart, this term also includes sand and gravel pits 
that received CCR, and abandoned CCR piles.
b. Revision to Definition of CCR Unit
    EPA is proposing to modify the definition of CCR unit by stating 
that CCR management units are not covered by the definition of a CCR 
unit. See proposed regulatory text at Sec.  257.53. Under the existing 
regulations, CCR units are defined as CCR landfills and CCR surface 
impoundments, as well as any lateral expansion of a CCR landfill or CCR 
surface impoundment. In addition, the term CCR unit already covers 
inactive CCR surface impoundments at active facilities because these 
units are CCR surface impoundments. Similarly, because a legacy CCR 
surface impoundment is a CCR surface impoundment, these units are a CCR 
unit under the regulations.
    As currently structured, many regulations specify that they apply 
collectively to the owners and operators of ``CCR units,'' rather than 
listing out each individual type of unit. As discussed elsewhere in 
this preamble, EPA is proposing to extend only a subset of the existing 
requirements in part 257, subpart D to CCRMU, consisting of 
requirements for groundwater monitoring, corrective action, closure, 
post-closure care, and reporting and recordkeeping. However, EPA is not 
proposing to apply the part 257 location restrictions, liner design 
criteria, structural integrity criteria for impoundments, and operating 
criteria to CCRMU. In order to implement this approach with the fewest 
revisions to the existing regulations, EPA is proposing to exclude 
CCRMU from the definition of CCR unit and propose specific 
modifications to those provisions that EPA intends would apply to 
CCRMU. To state another way, CCRMU would not be subject to provisions 
only applicable to CCR units.
c. Revisions to the Definitions of Owner and Operator
    EPA is proposing revisions to the existing definitions of Owner and 
Operator. The existing definition of Owner is the ``person(s) who owns 
a CCR unit or part of a CCR unit.'' First, EPA is proposing to revise 
the definition to incorporate the concept of CCRMU into the existing 
definition because CCRMU are excluded from the definition of a CCR unit 
as discussed in the preceding Unit of the preamble. This would be 
accomplished by adding ``or CCR management unit'' to the existing 
definition. See proposed regulatory text at Sec.  257.53. Second, the 
Agency is proposing to revise the definition of Owner to include the 
owner(s) of the entire facility, which would be achieved by adding ``or 
a facility, whether in whole or in part'' to the definition. EPA is not 
proposing to revise the definition of a ``facility,'' which under the 
existing regulations means ``all contiguous land, and structures, other 
appurtenances, and improvements on land, used for treating, storing, 
disposing, or otherwise conducting solid waste management of CCR. A 
facility may consist of several treatment, storage, or disposal 
operational units (e.g., one or more landfills, surface impoundments, 
or combinations of them).'' 40 CFR 257.53.
    EPA is proposing this revision in part to account for the more 
complicated ownership arrangements that exist at some utilities. EPA 
has found that there may be multiple owners at the same facility; for 
example, one entity may hold title to a single impoundment, while 
another entity may own the remaining disposal units at the site. 
Moreover, ownership can change over time, as individual units or 
portions of the facility are parceled off. This proposal would also 
more accurately reflect the nature of the obligations EPA is proposing 
to establish for CCRMU. For example, as discussed below, EPA is 
proposing to require an investigation of the entire disposal facility 
to identify CCRMU. At many sites, this would involve areas other than 
those encompassed by the definition of a CCR unit, extending to all 
areas where disposal or other solid waste management may be occurring. 
Moreover, relying exclusively on the ``owner'' of the CCRMU may be 
ambiguous in this context, as at some sites the owner may not yet be 
aware that a CCRMU is present (e.g., because it results from the 
historic placement or accumulation of CCR). EPA recognizes that this 
proposal would apply to currently regulated facilities, but it is not 
clear that this revision would actually amend the entities that 
currently are liable. EPA expects that most (if not all) utilities 
currently operate as though the regulation already required the owner 
operator of the facility to take actions; for example, under the 
existing regulations owners and operators are required to conduct 
corrective action even where the plume has migrated beyond the 
footprint of the regulated unit.
    For similar reasons, EPA is proposing to revise the definition of 
Operator to incorporate the concept of CCRMU into the existing 
definition by adding ``or CCR management unit'' to the existing 
definition. See proposed regulatory text at Sec.  257.53. In addition, 
the Agency is proposing revisions to account for the unique 
characteristics of a CCRMU. In cases where the CCRMU is closed (i.e., 
not receiving waste or otherwise in operation) or is a historic 
placement or accumulation of CCR, there will not be an entity that 
neatly fits the normal concept of an ``operator,'' because there would 
be no current or ongoing oversight or activity with respect to the 
continued use of the unit. To avoid any ambiguity, EPA is proposing to 
revise

[[Page 32020]]

the definition of ``operator'' to clarify that the term Operator 
includes those person(s) or parties responsible for disposal or 
otherwise actively engaged in solid waste management of CCR. It also 
includes those responsible for directing or overseeing groundwater 
monitoring, closure, or post-closure activities at a CCR unit or CCRMU.
    Because multiple entities may potentially be liable, (owners and 
operators) EPA is providing the following guidance. Consistent with 
EPA's typical practice, unless otherwise provided in the regulations, 
as long as one responsible entity (an owner or operator) has complied 
with the requirements, EPA will consider the obligation satisfied as to 
all potentially liable parties and will initially rely on owners and 
operators to determine among themselves how best to ensure compliance 
with the requirements.
d. Conforming Revisions to Other Existing Definitions
    EPA is proposing revisions to eight definitions in Sec.  257.53 to 
make reference to CCRMU. These definitions currently refer only to CCR 
units and the proposed changes would add the words ``or CCR management 
unit'' to the definitions so as to incorporate the concept of CCRMU 
into the existing definition. The eight definitions for which EPA is 
proposing this revision are: Active life or in operation, Active 
portion, Closed, CCR landfill or landfill, Qualified person, Qualified 
professional engineer, State Director, and Waste boundary. EPA is not 
proposing to otherwise revise or reopen the substance of the existing 
definitions as they apply to CCR units. Accordingly, the Agency will 
not respond to any comments on these definitions as they apply to CCR 
units.
5. Facility Evaluation for Identifying CCR Management Units
    EPA is proposing that owners and operators of active or inactive 
facilities with one or more CCR unit(s) will need to conduct a facility 
evaluation. The purpose of the facility evaluation is to confirm 
whether any CCRMU exist on-site, and, if so, to delineate the lateral 
and vertical extent of the unit(s). In developing this proposal, EPA 
relied heavily on the RCRA subtitle C Facility Assessment process for 
identifying solid waste management units at a hazardous waste facility. 
In addition, EPA accounted for certain existing requirements in the CCR 
regulations; for example, under the 2015 CCR Rule, facilities were 
required to compile a history of construction for their existing 
impoundments. 40 CFR 257.73(c)(1). Facilities were generally able to 
obtain all of the information specified in Sec.  257.73(c)(1)(i) 
through (ix), even for units constructed decades ago. EPA expects that 
facilities will similarly be able to obtain the information that EPA is 
proposing would be required in the Facility Evaluation Report 
(discussed in Unit IV.B.5.b of this preamble).
    EPA is proposing a two-step process for a facility evaluation. The 
first step would consist of a thorough review of available records in 
combination with a physical facility inspection and any necessary field 
work, such as soil sampling, to fill any data gaps from the information 
obtained from the review of available records. See proposed regulatory 
text at Sec.  257.75(b). The second step of the facility evaluation 
would be to generate a Facility Evaluation Report to document the 
findings of the facility evaluation. See proposed regulatory text at 
Sec.  257.75(c).
a. Facility Evaluation for CCR Management Units
    EPA is proposing that during the facility evaluation the owner or 
operator of a CCR unit at an active facility or inactive facility would 
need to identify and delineate the extent, laterally and vertically, of 
any CCRMU at the facility. EPA is proposing a two-step process by which 
the facility would make those determinations: the first would be 
conducting a facility evaluation and the second would be the drafting 
of a Facility Evaluation Report. EPA is proposing that the deadline to 
initiate the facility evaluation would be no later than the effective 
date of the final rule in Sec.  257.75(b).
    A facility evaluation would begin with a review of all existing 
records and documents readily and reasonably available to or attainable 
by the facility, that contain information regarding any past and 
present CCR management that resulted in the accumulation of CCR on the 
ground. Consistent with the proposed definition of a CCRMU, in this 
context EPA considers the terms ``placement'' and ``receipt'' to 
include situations in which spilled or released CCR has been left on 
the ground. During this first step, the facility would be required to 
gather and review information to identify potential locations of CCR 
placement, and to determine preliminary boundaries and depths of any 
CCRMU. EPA is also proposing that a facility evaluation would include a 
physical inspection of the facility. Where necessary, the physical 
inspection would include field investigation activities, such as 
conducting exploratory soil borings, geophysical assessments, or any 
other similar physical investigation confirmation activities to 
establish the location and boundaries of identified CCRMU, and to 
affirmatively rule out other areas of potential CCR placement at the 
facility that were identified during the information review. EPA is 
further proposing that the scope of the facility evaluation would be 
the entire facility as the term is currently defined in 40 CFR 257.53 
and the evaluation would need to include all of the information 
specified in the CCRMU Facility Evaluation Report.
    As noted, the facility evaluation would begin with a review of all 
readily and reasonably available information regarding past and present 
placement of CCR on the ground at the facility. In this first stage, 
the facility would need to gather all existing information that may be 
useful to determine any locations at the facility where CCR may have 
been placed (including spilled) on the ground. EPA expects that in this 
initial phase, the facility would cast a wide net, and collect all 
information that could potentially contain useful information to 
identify the potential locations of CCR placement at the facility. 
Finally, to complete the information review, the investigatory process 
would need to be documented, any data gaps identified, and plans for 
conducting a physical inspection of the site to verify locations, 
boundaries, and volumes of CCR placement at the facility would need to 
be formalized. Each step of this process is described in greater detail 
below.
i. Information Gathering
    The first step in the facility evaluation process involves the 
collection of information that contains any information on whether CCR 
was either routinely and systematically placed on the ground, or where 
facility activities otherwise resulted in measurable accumulations of 
CCR on the ground. The quality and reliability of the information 
review will depend greatly on the owner's and operator's ability to 
collect relevant information. Information reviews may provide 
misleading results when significant sources of information are not 
considered. EPA is proposing that the information that must be gathered 
during this step would include any documents that contain information 
relevant to past facility operations and waste disposal processes. By 
the conclusion of the facility evaluation, EPA expects that the 
facility would be able to identify the date, locations, durations, and 
volumes or estimated quantities of CCR placement.

[[Page 32021]]

    EPA expects that the amount of available written information and 
documentation that will be available for review during the document 
review phase may vary by facility. However, the following documents 
developed as part of complying with part 257, which are available to 
facilities, would normally contain information that can be useful in 
identifying CCRMU: inspection reports; history of construction reports; 
fugitive dust control plans; annual groundwater monitoring and 
corrective action reports; ASDs; ACM reports or other corrective action 
reports; and closure plans and reports. Further, there are other 
sources of readily available data that frequently contain information 
relevant to past facility operations and waste disposal processes, such 
as facility compliance reports produced for non-CCR programs (e.g., 
Toxic Substances Control Act [TSCA]/Occupational Safety and Health 
Administration [OSHA]/National Pollutant Discharge Elimination System 
[NPDES]/Clean Air Act [CAA]/Clean Water Act [CWA]); permits and permit 
applications, including NPDES, solid waste, dam safety, and air 
permits; historical and contemporary monitoring and reporting data, and 
facility operating logs and maps; and site imagery including available 
historical aerial photographs, site photographs, topographic maps, and/
or engineering or construction drawings, including drawings for 
physical facility improvement projects, such as surface water control, 
water and power infrastructure and utilities, roads, berms, ponds and/
or other physical features at the facility. EPA expects that facilities 
would search available records to determine whether they contain 
information relevant to the potential existence and locations of CCRMU.
    EPA is further proposing to require that owners and operators 
gather information by conducting meetings and interviews with current 
or former facility personnel and any available state and local 
officials familiar with the facility to the extent that those persons 
are available and have knowledge about past and/or present facility 
operations. The goal of the interview process would be to help gather 
any information relevant to the facility operations and waste disposal 
processes. EPA's expectation is that a good faith effort be made to 
identify key individuals that may have direct knowledge of the 
facility's historic CCR management to fill in data gaps and/or verify 
existing information. The expectation is qualitative and dependent on 
the reasonableness with which individuals can be identified and 
contacted. However, the purpose and process for determining the need 
for and the extent of employee interviews, or lack thereof, should be 
documented in the report. It is in the facility's best interest to 
evaluate historic management of CCR at the facility, identify CCR 
management units used throughout that duration, and, where gaps exist, 
try to identify individuals that may have information or direct 
knowledge regarding CCR management during those times. EPA expects 
that, when necessary, individuals involved in making decisions 
regarding CCR management during historic operations and/or implementing 
those decisions in the field would be able to be identified based on 
job titles and duties, time and duration of work service, and/or 
specific expertise using the facility's human resource records. Most 
government offices keep records of complaints, permits, and/or other 
correspondence that should be reviewed as part of the site evaluation. 
Individual officials in these records may be identified, particularly 
where they were involved with issues where CCR was managed or placed on 
the ground, or released to the environment through the air, surface 
water or groundwater.
    It is estimated that the compliance cost associated with meeting 
and/or interviewing in-house personnel would be negligible for current 
employees, and minimal (less than 8 hours) for former employees since 
some effort may be involved with trying to locate and contact them. In 
addition to the cost for owners and operators to review state or local 
records for the facility during the facility evaluation, it is 
estimated that the cost associated with contacting any necessary state 
or local officials or offices would be minimal (less than 8 hours) 
since it is unlikely they would be the only source of information for 
CCR management activities at the facility, and their knowledge of any 
CCR management units may be limited.
ii. Information Evaluation
    During this stage, EPA is proposing to require that a P.E. review 
the documents and information gathered during the initial step of 
review to draw conclusions regarding the existence of CCRMU at the 
facility. At the end of this stage, EPA expects the facility to 
identify: (1) Any areas where the facility can affirmatively conclude 
based on the available information that one or more CCRMU are present; 
and (2) Any areas where the available information indicates that CCR 
may have been either routinely and systematically placed on the ground, 
or where facility activities otherwise could have resulted in 
measurable accumulations of CCR on the ground (i.e., areas where the 
available information indicates that one or more CCRMU may be present).
    Each of the information sources discussed above can provide 
valuable information that can be used to identify the existence and 
locations of CCRMU. Some specific examples are provided below:
    Environmental reports for multimedia inspections contain useful 
information on site management practices, monitoring data, and unit 
conditions. These reports can also describe comprehensive monitoring 
evaluations at the site that can indicate where releases or areas of 
concern exist. Multimedia permit and permit applications contain large 
amounts of information on the facility design, waste management 
practices including how wastes were disposed of, and the physical 
characteristics of the surrounding area. These documents can contain 
old topographic maps, facility figures and drawings, wastestream flow 
diagrams, and unit and process descriptions.
    If a groundwater monitoring report for a CCR unit indicates that 
contaminant levels in groundwater monitoring wells are the result of 
CCRMU rather than the monitored CCR unit, this would need to be further 
investigated during the facility evaluation process to fully delineate 
the locations of areas where CCR was placed on the ground, including 
the size of the unit and other related unit details.
    Similarly, a review of aerial photographs can identify potential 
CCRMU at the facility at locations that have become overgrown or 
otherwise hidden over time. When used in conjunction with USGS 
topographic maps, owners and operators could look for evidence that may 
be indicative of placement of CCR on the ground. As an example, if 
aerial photographs and USGS topographic maps indicate the existence of 
a pond or dam system at the site, this may be enough to warrant further 
investigation of available documents and may require field 
investigation depending on the strength of information to determine if 
the changes were made to allow placement of CCR on the ground.
    Finally, one of the primary purposes of the information review is 
to provide an understanding of the CCR management activities at the 
facility, allowing for subsequent observations during the physical site 
inspection to be focused to the greatest extent practical. While 
information obtained during the

[[Page 32022]]

review may be insufficient to support affirmative conclusions regarding 
the existence or non-existence of a CCRMU, based on the information 
available at most facilities, EPA expects that it will be possible to 
determine which areas at the facility would need to be inspected, and 
the type of data that would be needed to draw definitive conclusions. 
The Agency expects that all of the information gathered in the 
information review will be relevant to determining the areas to be 
inspected during the physical (visual) site inspection. Further, the 
information gathered during the information review would be used to 
support any necessary field activities.
iii. Physical Site Inspection
    EPA is proposing to require that a facility conduct a physical site 
inspection of the entire facility in all cases. The purpose of the 
physical site inspection is to visually inspect the entire facility for 
evidence of CCR placement on the ground, ensure that all CCRMU have 
been identified, and fill any data gaps identified during the initial 
information evaluation. To that end, EPA is proposing that the physical 
site inspection must consist of a visual inspection of the entire 
facility to look for evidence that CCR is currently being managed on 
the ground. At a minimum, a facility would be required to visually 
inspect the site to confirm the information obtained from the 
information review phase and to identify any anomalies that warrant 
further investigation, such as an unnatural topographic rise or 
depression or an area where unspecified liquid waste was applied over 
several years. In addition, EPA is proposing that the facility would be 
required to conduct any field work such as soil sampling necessary to 
determine whether areas that had been identified as a potential CCRMU 
in fact contain CCR and to obtain the information required for the 
Facility Evaluation Report.
    The complexity of past and current facility operations, combined 
with the amount of data that was available for review during the 
information review phase would impact how extensive the facility 
inspection must be. For example, if facility records are sparse or 
contain data gaps, the Agency expects that the facility inspection 
would be more thorough than in situations where detailed records exist. 
However, even in situations where detailed facility records exist, the 
facility must still conduct a visual inspection to ensure that all 
CCRMU have been identified, even if those areas were not identified in 
the initial document review. In addition, EPA expects that in most 
cases, a facility will need to conduct some sampling or other fieldwork 
in order to obtain all the information required for the Facility 
Evaluation Report. For example, even if the facility had as-built 
engineering drawings for an old landfill, EPA expects that in some 
cases the facility may still need to conduct some sampling to establish 
the lateral and vertical dimensions of the CCRMU. If, after conducting 
a thorough document review and a visual inspection, the facility has 
found no evidence of any CCRMU, no further testing or sampling would be 
required to conclude that there are no CCRMU present at the facility. 
EPA is not proposing to require facilities to conduct widespread site 
sampling to prove that no CCRMU exist on-site. All recorded 
observations and data gathered during the facility evaluation, 
including any conclusions regarding the status of each CCRMU at the 
facility, must be assembled and incorporated into a Facility Evaluation 
Report, which is described in detail below.
b. Facility Evaluation Report for CCR Management Units
    After completing the first step of the facility evaluation process, 
EPA is proposing to require the owners and operators of active or 
inactive facilities with one or more CCR unit(s) to compile and place 
in the operating record information pertaining to every CCRMU located 
at the facility no later than 3 months after the effective date of the 
final rule at Sec.  257.75(c). The Facility Evaluation Report must be 
posted to the facility's CCR publicly accessible internet site within 
30 days of that date. In developing the list of items to be included in 
the Facility Evaluation Report, the Agency considered certain 
requirements from existing regulations for History of Construction 
reports that must be generated for existing CCR surface impoundments at 
Sec.  257.73(c)(1) as well as other requirements necessary to provide 
additional information about each CCRMU at the facility. In addition, 
the Agency is proposing to require that the Facility Evaluation Report 
include a certification from a P.E. stating that the Facility 
Evaluation Report meets the requirements at Sec.  257.75(c). See 
proposed regulatory text at Sec.  257.75(d). Further, the Agency is 
proposing to require that the Facility Evaluation Report include a 
certification to be signed by the owner or operator or an authorized 
representative similar to the certification that is required at Sec.  
257.102(e) and Sec.  257.102(f) for existing units undergoing closure. 
See proposed regulatory text at Sec.  257.75(e).
    EPA is proposing that the Facility Evaluation Report must contain 
the following: (1) The name and address of the person(s) owning and 
operating the facility; the unit name associated with any CCR unit and 
CCRMU at the facility; and the identification number of each CCR unit 
and CCRMU if any have been assigned by the state; (2) The location of 
any CCRMU identified on the most recent U.S. Geological Survey (USGS) 
7.5-minute or 15-minute topographic quadrangle map, or a topographic 
map of equivalent scale if a USGS map is not available, with the 
location of each CCR unit at the facility identified; (3) A statement 
of the purpose(s) for which each CCRMU at the facility is or was being 
used; (4) A description of the physical and engineering properties of 
the foundation and abutment materials on which each CCRMU is 
constructed; (5) A discussion of any known spills or releases of CCR 
from each CCRMU and whether or not the spills or releases were reported 
to state or federal agencies; (6) Any record or knowledge of structural 
instability of each CCRMU; (7) Any record or knowledge of groundwater 
contamination associated or potentially associated with each CCRMU; (8) 
Size of each CCRMU, including the general lateral and vertical 
dimensions and an estimate of the volume of waste contained within the 
unit; (9) Dates when each CCRMU first received CCR and when each CCRMU 
ceased receiving CCR; (10) Specification of all CCR wastes that have 
been managed in each CCRMU at the facility; (11) A narrative 
description, including any applicable engineering drawings or reports 
of any closure activities that have occurred; (12) A narrative that 
documents the nature and extent of field oversight activities and data 
reviewed as part of the facility evaluation process, and that lists all 
data and information that was reviewed indicating the absence or 
presence of CCRMU at the facility; and (13) Any supporting information 
used to identify and assess CCRMU at the facility, including but not 
limited to any construction diagrams, engineering drawings, permit 
documents, wastestream flow diagrams, aerial photographs, satellite 
images, historical facility maps, any field or analytical data, 
groundwater monitoring data or reports, inspection reports, 
documentation of interviews with current or former facility workers, 
and other documents or sources of information used to identify and 
assess CCRMU at the facility.

[[Page 32023]]

    As stated above, the Agency is proposing that the Facility 
Evaluation Report include a certification to be signed by a P.E. and 
the owner or operator or an authorized representative. Owners and 
operators of active or inactive facilities with one or more CCR unit(s) 
that do not contain any CCRMU would need to complete and place in the 
operating record a certified Facility Evaluation Report documenting the 
steps taken during the facility evaluation to determine the absence of 
any CCRMU. The Facility Evaluation Report must be placed in the 
facility operating record (Sec.  257.105(f)(25)), submitted to the 
appropriate regulating entity (Sec.  257.106(f)(24)), and published on 
the facility's website (Sec.  257.107(f)(24)).
    While these requirements apply to facilities with one or more CCR 
units, owners and operators are required to compile this information 
only to the extent available. EPA acknowledges that there may be 
certain information or data that may be unknown or lost. Therefore, in 
this proposed rule, EPA is using the phrase ``to the extent available'' 
and clarifying that the term requires the owner or operator to provide 
information in the Facility Evaluation Report only to the extent that 
such information is reasonably and readily available. EPA intends that 
facilities provide relevant information only if documentation exists. 
EPA does not expect owners or operators to provide anecdotal or 
speculative information regarding the presence or absence of CCRMU. 
However, if data gaps exist, owners or operators subject to this 
proposed rule may need to collect additional field data to fill the 
gaps.
    As stated previously, most of the activity needed to complete the 
Facility Evaluation and Facility Evaluation Report consists of 
reviewing reports and other documentation that already exist as a 
consequence of complying with other provisions in part 257, such as the 
history of construction, site or unit inspection reports, aerial 
imagery, quality assurance reports, groundwater monitoring and 
corrective action reports, or historic boring log reviews (e.g., 
subsurface investigations, geotechnical studies). Therefore, EPA 
estimates the hiring and onboarding of a contractor, data compilation, 
data review, conducting a site inspection, data analyses, and 
generation of a P.E.-certified report will take a total of 8 to 12 
weeks or 2 to 3 months. See Unit IV.A.2.d. Where new analyses are 
needed (e.g., sampling to establish the dimension of a CCRMU), they are 
assumed to be minor with data inputs for performing these analyses 
existing and readily available and capable of being conducted 
concurrently with some of the data review and report generation. 
Therefore, EPA believes the proposed deadline for the completion of the 
Facility Evaluation Report of no later than 3 months after the 
effective date of the final rule will be sufficient for the completion 
of these activities.
6. Applicable Existing CCR Requirements for CCR Management Units and 
Compliance Deadlines
a. Fugitive Dust Requirements for CCR Management Units
    The air criteria in the existing regulations address the pollution 
caused by windblown dust, by requiring the owners and operators of CCR 
units to minimize CCR from becoming airborne at the facility. 40 CFR 
257.80. These requirements apply to the entire facility, which means 
that the owner or operator is to minimize CCR fugitive dust originating 
not only from the CCR unit, but also from roads and other CCR 
management and material handling activities at the facility. 
Consequently, under this proposal, CCRMU would already be covered by 
the fugitive dust requirements in Sec.  257.80 because CCRMU are 
located at facilities with a CCR unit. EPA is therefore only proposing 
to make those changes to the fugitive dust requirements in Sec.  257.80 
that are necessary to make clear that these requirements also apply to 
CCRMU. Specifically, EPA is to add ``CCRMU'' to the list of units 
subject to the requirements under Sec.  257.80 and associated 
provisions under Sec. Sec.  257.105 through 257.107. EPA solicits 
comments on amending Sec.  257.80(b)(6) to include a deadline for 
facilities to amend the fugitive dust control plan no later than 30 
days following a triggering event, such as the closure of a CCRMU or 
change in facility or CCR unit operations.
b. Groundwater Monitoring and Corrective Action Requirements for CCR 
Management Units
    The existing groundwater monitoring criteria in Sec. Sec.  257.90 
through 257.95 require an owner or operator of a CCR unit to install a 
system of monitoring wells and specify procedures for sampling these 
wells. Further, it sets forth methods for analyzing the groundwater 
data collected to detect hazardous constituents (e.g., toxic metals) 
and other monitoring parameters in Appendix III or IV (e.g., pH, TDS) 
released from the units. 40 CFR 257.93. Once a groundwater monitoring 
system and groundwater monitoring program has been established for a 
CCR unit the owner or operator must conduct groundwater monitoring and, 
if the monitoring demonstrates an exceedance of the groundwater 
protection standards for identified constituents in Appendix IV of part 
257, corrective action is required. These requirements apply throughout 
the active life and post-closure care period of the CCR unit. EPA is 
proposing that the same groundwater monitoring and corrective action 
requirements that EPA is proposing to establish for legacy CCR surface 
impoundments would apply to CCRMU.
    The existing groundwater monitoring and corrective action 
requirements in Sec. Sec.  257.90 through 257.98 are essentially the 
same requirements that have been applied to both hazardous waste and 
municipal solid waste disposal units for decades, and with the 
exception of the one revision that EPA is proposing for legacy CCR 
surface impoundments, there is nothing about CCRMU that makes them 
distinct enough to warrant separate requirements. Each of the 
individual requirements are discussed in greater detail below.
i. Design and Installation of the Groundwater Monitoring System for CCR 
Management Units
    EPA is proposing that owners and operators of CCRMU install the 
groundwater monitoring system as required by Sec.  257.91 no later than 
6 months from the effective date of the rule. See proposed regulatory 
text at Sec.  257.90(b)(3)(i). The rationale for this compliance date 
is described in Unit IV.A.2.f.i of this preamble.
ii. Development of the Groundwater Sampling and Analysis Plan for CCR 
Management Units
    EPA is proposing to require that owners and operators of CCRMU 
comply with the existing groundwater sampling and analysis program 
requirements for CCR units, including the selection of the statistical 
procedures, that will be used for evaluating groundwater monitoring 
data. 40 CFR 257.93 and 257.91(d)(3). See, proposed regulatory text at 
Sec.  257.90(b)(3)(ii). EPA is proposing this requirement to be 
completed no later than 6 months after the effective date of the final 
rule. The rationale for this compliance date is described in Unit 
IV.A.2.f.ii of this preamble.
iii. Detection Monitoring Program and Assessment Monitoring Program 
Combined
    EPA is proposing to require that facilities simultaneously initiate 
sampling and analysis of all Appendix

[[Page 32024]]

III and IV constituents at CCRMU to expedite the detection and cleanup 
of contamination from these abandoned unlined impoundments. This is the 
only revision to the existing groundwater monitoring requirements in 
Sec. Sec.  257.90 through 257.95 that EPA is proposing to make for 
CCRMU.
    As laid out in Unit IV.B.1, there is good reason to believe that 
CCRMU are currently contaminating groundwater. And as is the case with 
legacy CCR surface impoundments, at sites where the unit has 
potentially been leaking for a long time, the need to protect human 
health and environment by quickly detecting the constituents of concern 
in Appendix IV warrants expediting any necessary corrective action. 
See, USWAG 901 F.3d at 427-30. The rationale for this proposal is 
further explained in Unit IV.A.2.f.iii of this preamble.
iv. Collection and Analyses of Eight Independent Samples for CCR 
Management Units
    EPA is proposing that no later than 24 months after the effective 
date of the final rule, owners or operators of CCRMU initiate the 
detection monitoring program by completing sampling and analysis of a 
minimum of eight independent samples for each background and 
downgradient well, as required by Sec.  257.94(b). See proposed 
regulatory text at Sec.  257.100(f)(4)(iii). Within 90 days after that, 
they must identify any SSIs over background levels for the constituents 
listed in Appendix III of this part, as required by Sec.  257.94. EPA 
is also proposing that by this same deadline they initiate the 
assessment monitoring program by establishing groundwater protection 
standards and beginning the evaluation of the groundwater monitoring 
data for statistically significant levels over groundwater protection 
standards for the constituents listed in Appendix IV of this part as 
required by Sec.  257.95. Then, if a statistically significant level 
over a groundwater protection standard for any of the constituents 
listed in Appendix IV of this part is found, the owner or operator of 
the legacy CCR surface impoundment must perform any required corrective 
action in accordance with Sec. Sec.  257.96 through 257.98. The 
rationales for these deadlines are explained in Unit IV.A.2.f.iv. of 
this preamble.
v. Preparation of Initial Groundwater Monitoring and Corrective Action 
Report for CCR Management Units
    EPA is proposing to apply the existing requirements in Sec.  
257.90(e) for preparation of an annual groundwater monitoring and 
corrective action report to CCRMU and that owners and operators of 
CCRMU comply no later than January 31 of the year following the 
calendar year a groundwater monitoring system has been established for 
such CCR management unit, and annually thereafter. See proposed 
regulatory text at Sec.  257.90(e)(1). The rationale for the components 
of this report and the expedited compliance deadline is explained in 
Unit IV.A.2.f.v of this preamble.
c. Closure and Post-Closure Care Criteria for CCR Management Units
    EPA is proposing to apply the existing closure criteria for CCR 
surface impoundments in Sec. Sec.  257.101 and 257.102 to CCRMU. EPA is 
also proposing to require that all CCRMU initiate closure, whether or 
not they are currently contaminating groundwater. Consistent with the 
proposal for legacy CCR surface impoundments, EPA is proposing to 
explicitly state that the alternative closure provisions in Sec.  
257.103 would not be applicable to CCRMU. Finally, EPA is proposing to 
apply the existing post-closure care requirements in Sec.  257.104 to 
CCRMU. Each of these proposals are discussed in detail below
i. Criteria for Conducting Closure of CCRMU and Requirement To Close
    Requiring the closure of CCRMU in accordance with Sec. Sec.  
257.101-257.102 would provide significant risk mitigation. As laid out 
in Unit IV.B.1 of this preamble, CCRMU at both inactive and active 
facilities pose significant risks to human health and the environment, 
at levels that are at least as significant as the risks presented by 
legacy CCR surface impoundments and the units currently regulated under 
the 2015 CCR Rule. Additionally, this is consistent with the existing 
CCR regulations, which require closure of all CCR units that have 
ceased receiving waste to mitigate the risks such units pose to human 
health and the environment. See, 40 CFR 257.102(e)(1). In particular, 
risks identified on a national scale are from releases of arsenic, 
lithium and molybdenum to groundwater. Available toxicological profiles 
indicate that ingestion of arsenic is linked to increased likelihood of 
cancer in the skin, liver, bladder and lungs, as well as nausea, 
vomiting, abnormal heart rhythm, and damage to blood vessels; ingestion 
of lithium is linked to neurological and psychiatric effects, decreased 
thyroid function, renal effects, cardiovascular effects, skin 
eruptions, and gastrointestinal effects; and ingestion of molybdenum is 
linked to higher levels of uric acid in the blood, gout-like symptoms, 
and anemia. 80 FR 21451. To date, groundwater monitoring required by 
the 2015 CCR Rule has revealed that at least 40% of currently regulated 
surface impoundments and landfills have identified groundwater 
contamination and require corrective action to mitigate the associated 
risks. This number is expected to increase as more facilities come into 
full compliance with the rule. Another 23% of units have identified 
evidence of leakage and continue to monitor groundwater to ensure that 
contamination does not occur before the unit can be closed and source 
controls put in place. In many cases, CCRMU are historical landfills 
and surface impoundments. Thus, the relevant release pathways, exposure 
routes, and associated harm that can result are the same. As noted 
above, the risks associated with these CCRMU are anticipated to be at 
least as significant as the universe of currently operating units. 
There is further evidence that the risks may be even higher. This is a 
result of the fact that: (1) These units have been present onsite for 
longer and had more time to leak, and (2) Riskier disposal practices, 
such as co-management with coal refuse, were more common in the past. 
As the D.C. Circuit explained, RCRA requires EPA to set minimum 
criteria for sanitary landfills that prevent harm, not merely to ensure 
that contamination is remediated. See, USWAG, 901 F.3d at 430.
    Further, EPA does not believe that any facility will need to 
continue to use a CCRMU. These units, by definition, are not currently 
receiving CCR; any unit currently receiving CCR is regulated under the 
existing regulations. Instead CCRMU have been ``closed'' by the 
facility, presumably in accordance with whatever state requirements 
were in effect at the time, or have been left inactive on-site. Because 
a continued need to use the disposal unit is a critical component of 
the alternative closure demonstrations (at Sec.  257.103(f)), it 
appears that no CCRMU could qualify under the existing provisions. 
Accordingly, EPA does not believe these provisions are relevant to 
CCRMU.
    While EPA is proposing that the CCR unit closure requirements would 
apply, EPA requests comment on other approaches to how a facility might 
implement the requirement to close at a site where the CCRMU lies 
beneath an operating unit. EPA also solicits comments on whether EPA 
should not mandate the closure of CCRMU. However, EPA is concerned that 
if CCRMU were not required to close, EPA

[[Page 32025]]

would not adequately address the risks from those units that have waste 
below the water table. In general, EPA considers that closure is the 
most certain way to adequately address the source of any releases from 
these units. Although EPA could rely upon the existing corrective 
action requirements to achieve source reduction, the Agency is 
concerned that this will not adequately prevent harm, as the statute 
requires, because these requirements would only apply upon a 
determination that the CCRMU has contaminated the aquifer. In addition, 
the closure requirements in Sec.  257.102 provide a uniform approach 
that EPA is confident will adequately protect human health and the 
environment in all situations.
    Given the locations of many CCRMU (located in floodplains, or 
wetlands, or near large surface water bodies), EPA is concerned that 
the base of these units may intersect with the groundwater beneath the 
unit. As EPA has previously explained, where the base of a surface 
impoundment intersects with groundwater, the facility will typically 
need to include engineering measures specifically to address any 
continued infiltration of groundwater into the impoundment in order to 
close with waste in place consistent with Sec.  257.102(d). See, e.g., 
87 FR 72989 (Nov 28, 2022), 85 FR 12456, 12464 (March 3, 2020). The 
same holds true for CCRMU that intersect with groundwater. The existing 
requirements in Sec.  257.102(d)(1) and (3) apply to all CCR units and 
EPA is proposing that these provisions would also apply to CCRMU 
without revision. By contrast, the existing requirements in Sec.  
257.102(d)(2), which establish performance standards for drainage and 
stabilization of the unit, only apply to CCR surface impoundments. 
These performance standards are critical to ensuring that units that 
contain liquids are properly and safely closed, and therefore should 
apply to any unit, including a CCRMU and a CCR landfill, where the CCR 
remains saturated. Accordingly, EPA is proposing to revise Sec.  
257.102(d)(2) so that it applies to all CCR units and CCRMU. EPA 
provides a background discussion of the existing closure performance 
standards below. It is important to note that if there is no liquid in 
the unit, the proposed revision would not require the facility to do 
anything to meet the performance standards.
    The CCR closure requirements applicable to closing with waste in 
place include general performance standards and specific technical 
standards that set forth individual engineering requirements related to 
the drainage and stabilization of the waste and to the final cover 
system. The general performance standards and the technical standards 
complement each other, and both must be met at every site.
    The specific technical standards related to the drainage of the 
waste in the impoundment require that, ``free liquids must be 
eliminated by removing liquid wastes or solidifying the remaining 
wastes and waste residues.'' 40 CFR 257.102(d)(2)(i). Free liquids are 
defined as all ``liquids that readily separate from the solid portion 
of a waste under ambient temperature and pressure,'' regardless of 
whether the source of the liquids is from sluiced water or groundwater. 
40 CFR 257.53. Consequently, the directive applies to both the 
freestanding liquid in the impoundment and to all separable porewater 
in the impoundment, whether the porewater was derived from sluiced 
water, stormwater run-off, or groundwater that migrates into the 
impoundment. In situations where the waste in the unit is inundated 
with groundwater, the requirement to eliminate free liquids thus 
obligates the facility to take engineering measures necessary to ensure 
that the groundwater, along with the other free liquids, has been 
permanently removed from the unit prior to installing the final cover 
system. See, 40 CFR 257.102(d)(2)(i).
    In addition to the process-specific technical requirements, all 
closures must meet the requirements in the general performance standard 
to ``control, minimize or eliminate, to the maximum extent feasible,'' 
both post-closure infiltration of liquids into the waste and releases 
of CCR or leachate out of the unit to the ground or surface waters, and 
to ``preclude the probability of future impoundment of water, sediment, 
or slurry.'' 40 CFR 257.102(d)(1)(i), (ii). EPA construes the word 
``infiltration'' in this regulation as a general term that refers to 
the migration or movement of liquid into or through a CCR unit from any 
direction, including the top, sides, and bottom of the unit. This is 
consistent with the plain meaning of the term. For example, Merriam-
Webster defines infiltration to mean ``to pass into or through (a 
substance) by filtering or permeating'' or ``to cause (something, such 
as a liquid) to permeate something by penetrating its pores or 
interstices.'' Similarly, the Cambridge English Dictionary defines 
infiltration as ``the process of moving slowly into a substance, place, 
system, or organization,'' and provides the following example ``It is 
important to manage moisture infiltration into buildings.'' https://dictionary.cambridge.org/us/dictionary/english/infiltration (website 
visited 10/22/2022). None of these definitions limit the source or 
direction by which the infiltration occurs.
    In situations where the groundwater intersects an unlined CCR unit, 
water may infiltrate into the unit from the sides and/or bottom of the 
unit because the base of the unit is below the water table. In this 
scenario, the CCR in the unit will be in continuous contact with water. 
This contact between the waste and groundwater provides a potential for 
waste constituents to be dissolved and to migrate out of (or away from) 
the closed unit. In such a case, the general performance standard also 
requires the facility to take measures, such as engineering controls, 
that will ``control, minimize, or eliminate, to the maximum extent 
feasible, post-closure infiltration of liquids into the waste'' as well 
as ``post-closure releases to the groundwater'' from the sides and 
bottom of the unit. 40 CFR 257.102(d)(1).
    Whether any particular unit can meet these performance standards is 
a fact and site-specific determination that will depend on a number of 
considerations, such as the hydrogeology of the site, the design and 
construction of the unit, and the kinds of engineering measures 
implemented at the unit. Accordingly, the fact that prior to closure 
the base of a unit intersects with groundwater does not mean that the 
unit may not ultimately be able to meet the performance standards in 
Sec.  257.102(d) for closure with waste in place. Depending on the site 
conditions, a facility may be able to meet these performance standards 
by demonstrating that a combination of engineering measures and site-
specific circumstances will ensure that as a consequence of complying 
with the closure performance standards, the groundwater will no longer 
be in contact with the waste in the closed unit. As one example, where 
groundwater intersects with only a portion of an impoundment, the 
facility could close that portion of the unit by removing the CCR from 
that area of the unit but leaving waste in place in other areas. As 
another example, if the entire unit sits several feet deep within the 
water table, engineering controls can potentially be implemented to 
stop the continued flow of groundwater into and out of the waste. See, 
EPA Office of Solid Waste, Closure of Hazardous Waste Surface 
Impoundments, SW-873, p 81 (September 1982), Revised Edition.
    Concerns have been raised that the existing regulations do not 
clearly support the above description. For

[[Page 32026]]

example, some have argued that the term ``infiltration'' only refers to 
the movement of water into a unit from the surface through a cover 
system, or that the regulations do not require facilities to eliminate 
``free liquids'' derived from groundwater. Although EPA strongly 
disagrees and considers that the plain text of the regulation already 
clearly communicates the positions laid out above, the Agency requests 
comment on whether to revise the existing regulatory text so that it 
addresses the particular issues that regulated entities have raised. 
Specifically, as discussed previously EPA is requesting comments on 
whether to include a regulatory definition of the term ``liquids,'' 
which could specify that the term includes free water, porewater, 
standing water, and groundwater. Similarly, EPA requests comment on 
whether to adopt a regulatory definition of the term ``infiltration,'' 
consistent with term's plain meaning and the dictionary definitions 
referenced above.
ii. Preparation of a Written Closure Plan for CCR Management Units
    EPA is proposing that owners and operators of CCRMU comply with the 
existing requirements of Sec.  257.102(b) requiring the preparation of 
a written closure plan. See proposed regulatory text at Sec.  
257.102(b)(2)(iii). EPA is proposing a deadline of 12 months after the 
effective date of the rule to complete the closure plan. The rationale 
for the components of this report and for this compliance date is 
described in Unit IV.A.2.g.ii of this preamble.
iii. Preparation of a Written Post-Closure Care Plan for CCR Management 
Units
    EPA is proposing that owners and operators of CCRMU would be 
required to comply with the existing requirement in Sec.  257.104(d) 
regarding the preparation of a written post-closure. See, proposed 
regulatory text at Sec.  257.104(d)(4)(iii). EPA is proposing to 
require the post-closure care plan no later than 12 months after the 
effective date of the final rule. The rationale for the components of 
this report and for this compliance date is described in Unit 
IV.A.2.g.iii of this preamble.
iv. Deadline To Initiate Closure for CCR Management Units
    EPA is proposing that owners and operators of CCRMU initiate 
closure no later than 12 months after the effective date of the final 
rule. See proposed regulatory text at Sec.  257.101(f). EPA's rationale 
for this timeframe is included in Unit IV.A.2.g.iv and Unit IV.A.2.a.ii 
of this preamble.
v. Deadline To Complete Closure for CCR Management Units
    The existing CCR regulations currently require (at Sec.  
257.102(f)) an owner or operator of a CCR surface impoundment generally 
to complete closure activities within five years from initiating 
closure. The regulations also establish the conditions for extending 
this deadline, upon a showing that additional time is necessary.
    EPA is proposing to apply the CCR surface impoundment closure 
timeframes because EPA has concluded that CCRMU closure will closely 
resemble CCR impoundment closures. First, as discussed in Unit 
IV.B.2.a, EPA identified a total of 134 areas where CCR is being 
managed, but which remain exempt under existing federal CCR 
regulations. Over half of these areas are associated with former, 
federally unregulated CCR surface impoundments. For those former 
impoundments that will be closed with waste in place, the owner or 
operator would need to procure substantial volumes of soil or borrow 
material to properly achieve the subgrade elevations needed to support 
the final cover system. For some CCRMU this material acquisition will 
involve the movement of tens of thousands of truckloads of soil or 
borrow material. This situation would also apply to certain CCR fill 
placements as well as to inactive CCR landfills where past waste 
disposal did not reach the landfill's design capacity (i.e., landfill 
airspace was not fully utilized). In these situations, EPA believes the 
timeframes to complete closure for existing CCR surface impoundments 
are more appropriate (i.e., 5 years) than, for example the 6 months 
(and limited time extensions) provided for existing CCR landfills.
    Second, EPA is finding through implementation of the existing 
regulations that a significant percentage of facilities are electing to 
close CCR units by removal of waste. If owners and operators of CCRMU 
were to similarly choose this approach to closure, a shorter timeframe 
would only be sufficient for smaller-sized CCRMU since removal 
operations often require tens of thousands of truckloads to relocate 
CCR to a suitable location.
    Finally, as discussed in Unit IV.B.6, the Agency is concerned that 
the base of at least some CCRMU may intersect with the groundwater 
beneath the unit because CCRMU may be located in floodplains or 
wetlands, or near large surface water bodies. EPA's experience in 
implementing the regulations is that such closures are generally more 
complex and take longer to complete. This is because the facility will 
typically need to incorporate engineering measures into the closure 
activities to ensure that the groundwater will no longer be in contact 
with the waste in the unit. EPA thus believes the timeframes to 
complete closure of CCRMU should be the same as the timeframes provided 
for existing CCR surface impoundments.
    In addition, EPA is proposing to make CCRMU eligible for limited 
time extensions to complete closure when justified by the owner or 
operator. EPA recognizes that there can be unforeseen and extraordinary 
circumstances that warrant additional time to close a CCRMU. For 
example, these circumstances can include climate of the location. 
Weather delays, and the need for coordination with and approvals from 
state regulatory agencies. Accordingly, the rule proposes to adopt the 
same procedures currently applicable to CCR surface impoundments, which 
would allow the owner or operator to obtain additional time to complete 
the closure of a CCRMU, provided the owner or operator can make the 
prescribed demonstrations. Consistent with the existing requirements 
for CCR surface impoundments, the amount of additional time that a 
facility could obtain would vary based on the size (using surface area 
acreage of the CCR unit as the surrogate of size) of the CCRMU. For 
CCRMU 40 acres or smaller, the maximum time extension is 2 years. For 
CCRMU greater than 40 acres, the maximum time extension is five 2-year 
extensions (10 years), and the owner or operator must substantiate the 
factual circumstances demonstrating the need for each 2-year extension. 
See proposed regulatory text at Sec.  257.102(f)(2).
vi. Post-Closure Care for CCR Management Units
    The existing post-closure care criteria require the monitoring and 
maintenance of units that have closed in place for at least 30 years 
after closure has been completed. 40 CFR 257.104. During this post-
closure period, the facility would be required to continue groundwater 
monitoring and corrective action, where necessary. EPA is proposing to 
apply these existing requirements to CCRMU without revision. These 
criteria are essential to ensuring the long-term safety of CCRMU.

[[Page 32027]]

d. Recordkeeping, Notification and Internet Posting for CCR Management 
Units
    As discussed in Unit IV.A.2.h of this preamble, the 2015 CCR Rule 
required at Sec. Sec.  257.105 through 257.107 for owner or operators 
of CCR units to record certain information in the facility's operating 
record. In addition, owners and operators are required to provide 
notification to states and/or appropriate Tribal authorities when the 
owner or operator places information in the operating record, as well 
as to maintain a website for this information. Similar to legacy CCR 
surface impoundments, EPA is proposing that owners and operators of 
CCRMU be subject to certain recordkeeping, notification, and website 
reporting requirements in the CCR regulations. EPA is proposing that 
the applicable recordkeeping requirements in Sec.  257.105, the 
notification requirements in Sec.  257.106, and posting on a website 
requirements at Sec.  257.107 would also apply to CCRMU. EPA is also 
proposing changes to add CCRMU to Sec.  257.107(a) to require the 
facility to notify the Agency using the procedures for the 
establishment of the website no later than the effective date of the 
final rule.

C. Technical Corrections

    Through the implementation of the 2015 CCR Rule, the Agency 
identified an incorrect CFR reference to the definition of technically 
feasible, technically infeasible, and wetlands EPA also identified 
inconsistencies in how publicly accessible internet sites are 
referenced. Therefore, EPA is proposing to amend the CCR regulations so 
that the regulations clarify definitions, accurately reference the 
definition of wetlands, and use consistent language when referring to 
publicly accessible internet sites. The Agency is also proposing to 
amend an incorrect reference to Sec.  257.99 in the groundwater 
monitoring scope section. Finally, EPA is requesting comment on 
extending the period for document retention and posting.
1. Definitions of ``Technically Feasible'' and ``Technically 
Infeasible''
    EPA is proposing to revise the definition of technically feasible 
to clarify that the terms technically feasible and feasible have the 
same meaning in the regulations. The existing regulations define 
technically feasible as ``possible to do in a way that would likely be 
successful.'' EPA codified this definition in 2020 when amending the 
alternative closure requirements for landfills and impoundments. 85 FR 
53542 (August 28, 2020). As EPA explained, the definition was based on 
two dictionary definitions of ``feasible'': ``capable of being done or 
carried out''(Merriam website (https://www.merriam-webster.com/dictionary/feasible)) and ``possible to do and likely to be 
successful'' (Cambridge English Dictionary (https://dictionary.cambridge.org/us/dictionary/english/feasible)). Id.
    However, some rule provisions use the term feasible. It is not the 
Agency's intent to distinguish between these terms. Therefore, EPA is 
proposing to add the term feasible to the existing definition of 
technically feasible to make clear that both terms have the same 
meaning in the regulations. This definition revision would be 
accomplished by adding ``or feasible'' to the existing definition so 
that the definition would read ``Technically feasible or feasible means 
possible to do in a way that would likely be successful.'' See proposed 
regulatory text at Sec.  257.53.
    For similar reasons, EPA is proposing to also revise the definition 
of technically infeasible to clarify that the terms technically 
infeasible and infeasible have the same meaning in the regulations. See 
proposed regulatory text at Sec.  257.53.
2. Wetlands Reference Correction
    When the 2015 CCR Rule was finalized in April 2015, Sec.  257.61(a) 
referenced Sec.  232.2 which contained a definition of wetlands. An EPA 
and United States Army Corps of Engineers joint final rule published 
June 29, 2015 (80 FR 37053) amended Sec.  232.2 by removing the 
definition of wetlands. However, the reference to Sec.  232.2 in Sec.  
257.61(a) of the 2015 CCR Rule was not updated. The proposed amendment 
would correct the CFR reference for the wetlands definition by 
referring to 40 CFR 230.41(a) (December 24, 1980, 45 FR 85344).
3. Groundwater Monitoring and Corrective Action Applicability
    EPA is proposing to correct a typographical error in the initial 
applicability paragraph of the groundwater monitoring and corrective 
action regulations. In Sec.  257.90(a), the existing regulations refer 
to the ``groundwater monitoring and corrective action requirements 
under Sec. Sec.  257.90 through 257.99''; however, there are no 
requirements codified under Sec.  257.99. This was brought to our 
attention by a state interested in permit program approval. To avoid 
confusion with the regulations, EPA is proposing to revise the section 
references in Sec.  257.90(a) to read ``groundwater monitoring and 
corrective action requirements under Sec. Sec.  257.90 through 
257.98.''
4. Publicly Accessible Internet Site
    EPA is proposing to change several provisions using the term ``CCR 
Web site'' to ``CCR website,'' which is the term used in Sec.  
257.107(a). The inconsistent spelling of CCR website was brought to our 
attention by a state interested in permit program approval. To avoid 
confusion with the regulations, EPA is proposing to correct such 
references in Sec. Sec.  257.100(e)(1)(iii) and 257.107(b) through (j).
5. Document Retention
    EPA is taking comment on extending the period for document 
retention and posting found in Sec. Sec.  257.105 and 257.107. The 
existing regulations generally require retention of documents in the 
operating record for a period of five years (Sec.  257.105(b)) and 
posting of documents on the facility publicly accessible CCR website 
for five years (Sec.  257.107(c)). The Agency now believes these time 
periods may be too short and that relevant information should remain 
publicly accessible for a longer time period. Under the existing 
requirements, information that is still relevant for CCR units could be 
removed from operating records and taken off websites well before the 
relevancy of that information has passed and goals of the record 
retention and posting requirements have been met. For example, for CCR 
unit closure plans that were posted in 2016 in accordance with Sec.  
257.102(b), the time periods have run, allowing closure plans to be 
removed from operating records and websites. This is true even if the 
facility has not initiated closure activity and may not initiate 
closure activity for many years. This was not consistent with EPA's 
original intent--either for the closure plan itself or for the posted 
information more generally--which was that the information should 
remain posted for as long as the information was relevant to evaluating 
the facility's compliance with the regulations. See, e.g., 80 FR 21335. 
The Agency continues to believe that much of the information, including 
plans, reports, and monitoring results, subject to the time period 
limits will remain relevant and should remain accessible for a much 
longer period than the original five years. The Agency is taking 
comment on how long these time periods should be extended. The Agency 
is considering a general increase in the retention period (e.g., 
fifteen years) or, alternatively, tying the retention period to a 
regulatory milestone for each unit (e.g., completion

[[Page 32028]]

of closure, post-closure care, or groundwater corrective action) and is 
seeking comment on which of these approaches, if any, the Agency should 
adopt. The Agency is considering this extension of retention time for 
all documents currently subject to the relevant retention time periods 
as all of these documents could remain relevant longer than the current 
time periods. Therefore, the goals of information availability and 
transparency would remain relevant for the CCR program.

V. Effect on State CCR Permit Programs

    The proposed revisions to the CCR regulations would both establish 
standards for new types of units and revise existing requirements for 
CCR units defined in and subject to the 2015 CCR Rule. For this reason, 
if EPA takes final action on all the proposed changes, the requirements 
for approval and retention of a state CCR permit program in accordance 
with RCRA section 4005(d) will change. How these revisions would affect 
states depends on whether the state has received approval for the 
provisions that are ultimately included in any final rule and whether 
the state is seeking full or partial approval of its permit program.
    If EPA has approved a state regulation pursuant to RCRA section 
4005(d), that state regulation will continue to operate in lieu of the 
federal program, even if EPA subsequently revises the federal analog of 
that regulation. See 42 U.S.C. 6945(d)(1)(A), (3). In essence this 
means that any federal revisions would not take effect in the approved 
state until the state revises the program to adopt them. In order to 
maintain approval, the state must revise such a regulation within three 
years of any revision to the federal CCR regulation that is more 
protective. See, 42 U.S.C. 6945(d)(1)(D)(i)(II). Conversely, where EPA 
has not approved a state requirement, the federal requirements continue 
to apply directly to the facilities in that state. As a consequence, 
any revisions to the federal requirements will take effect in states 
without an approved program because the federal requirements continue 
to operate.
    As discussed in Units IV.A and IV.B of this preamble, EPA is 
proposing to establish requirements for legacy CCR surface impoundments 
and CCRMU. Because legacy CCR surface impoundments and CCRMU are new 
types of federally regulated units, no state is currently approved to 
issue state CCR permits to such units in lieu of the federal CCR 
regulations. Thus, any state that wants approval to issue permits to 
such units will be required to update the state CCR regulations and go 
through the state CCR permit program approval process set forth in RCRA 
section 4005(d).
    As discussed in Units IV.B.9 and IV.C of this preamble, EPA is also 
proposing to revise requirements under the existing CCR regulations. 
The revised requirements will directly apply to affected facilities 
except to the extent EPA has already approved the state to issue 
permits for the original requirement. In such a case the state 
requirement will apply in lieu of the new federal requirement until the 
state program is revised. EPA considers at least one of these proposals 
(the proposal to expand Sec.  257.102(d)(2) to landfills that are 
inundated with groundwater) to be more stringent than the existing 
regulations.
    Accordingly, all states will have to consider whether to update 
their state CCR regulations and seek approval to issue permits for 
legacy CCR surface impoundments and CCRMU. In addition, states with 
approved CCR permit programs will be required to revise their 
regulations to address any new requirements applicable to CCR units, to 
the extent those requirements are more stringent than the approved 
state CCR permit program.\79\ Similarly, states that are currently 
working with the Agency to obtain approval of their state CCR permit 
program will need to update their state programs to address the new 
requirements applicable to CCR units if the state wishes to seek full 
program approval and the new requirements are more stringent.\80\
---------------------------------------------------------------------------

    \79\ Currently the states of Georgia, Oklahoma, and Texas have 
approval for state CCR permit programs.
    \80\ Currently, EPA is working with the states of Alabama, 
Arizona, Florida, Illinois, Indiana, Kansas, Louisiana, Maryland, 
Michigan, North Carolina, North Dakota, Pennsylvania, Tennessee, 
Utah, Virginia, West Virginia, Wisconsin, and Wyoming on drafting 
CCR regulations or a draft CCR permit program.
---------------------------------------------------------------------------

    The process for approving modifications is the same as for the 
initial program approval: EPA will propose to approve or deny the 
program modification and hold a public hearing during the comment 
period. EPA will then issue the final program determination within 180 
days of determining that the state's submission is complete.
    EPA requests comment on the effect of this proposed rule on state 
CCR permit programs. EPA specifically requests comment on whether the 
proposed revisions to the existing requirements that apply to CCR units 
will be more stringent than the existing state CCR permit requirements, 
such that the states with approved programs and states currently in the 
process of seeking approval would need to revise their state CCR permit 
program to retain or obtain approval, respectively.

VI. The Projected Economic Impact of This Action

A. Introduction

    EPA estimated the costs and benefits of this action in a Regulatory 
Impact Analysis (RIA), which is available in the docket for this 
action.

B. Affected Universe

    The universe of facilities and units affected by the proposed rule 
includes three categories. The first is comprised of facilities with 
legacy CCR surface impoundments. The RIA identifies 127 legacy CCR 
surface impoundments located at 59 facilities. The second component of 
the affected universe is composed of CCRMU. The RIA identifies 134 
units at 82 facilities. The final component of the universe is 
comprised of CCR landfills that are already regulated under the 2015 
CCR final rule, but which have waste in contact with groundwater. The 
RIA identifies 19 units.

C. Baseline Costs

    The RIA examines the extent to which baseline practices at legacy 
CCR surface impoundments and CCRMU address contamination in a manner 
consistent with the requirements of the proposed rule. To the extent 
that legacy CCR surface impoundments and CCRMU are already sufficiently 
addressing contamination, they are assumed to not incur costs or 
realize benefits under the proposed rule. To estimate the proportion of 
legacy CCR surface impoundments addressing contamination in the 
baseline, the RIA examines relevant federal and state programs and 
determines that about 5.5% of legacy CCR surface impoundments are 
addressing site contamination. To estimate the proportion of CCRMU 
addressing contamination, the RIA examines publicly available filings 
from owners and operators of regulated coal fired power plants. The RIA 
estimates that about 34% of CCRMU are undergoing sitewide corrective 
action and closure in a manner sufficient to meet the requirements of 
the proposed rule.

D. Costs and Benefits of the Proposed Rule

    The RIA estimates that the annualized costs of this action will be 
approximately $413 million per year when discounting at 7%. Of this, 
$237 million is attributable to the requirements for legacy CCR surface

[[Page 32029]]

impoundments, which are subject to the D.C. Circuit's order in USWAG, 
$170 million is attributable to the requirements for CCRMU, and $6 
million is attributable to requirements for landfills. The RIA 
estimates that the annualized costs of this action will be 
approximately $356 million when discounting at 3%. Of this, $204 
million is attributable to the requirements for legacy CCR surface 
impoundments, $146 million is attributable to the requirements for 
CCRMU, and $6 million is attributable to requirements for landfills. 
The costs of this proposed rule are discussed further in the RIA and 
include the costs of unit closure, corrective action, fugitive dust 
controls, structural integrity inspections, and recordkeeping and 
reporting.
    The RIA estimates that the annualized monetized benefits 
attributable to this action will be approximately $49 million per year 
when discounting at 7%. Of this, $30 million is attributable to the 
requirements for legacy CCR surface impoundments, $16 million is 
attributable to the requirements for CCRMU, and $3 million is 
attributable to requirements for landfills. The RIA estimates that the 
annualized monetized benefits attributable to this action will be 
approximately $77 million per year when discounting at 3%. Of this, $47 
million is attributable to the requirements for legacy CCR surface 
impoundments, $25 million is attributable to the requirements for 
CCRMU, and $5 million is attributable to requirements for landfills. 
The monetized benefits of this proposed rule are discussed further in 
the RIA, and include reduced incidents of cancer from the consumption 
of arsenic in drinking water, avoided intelligence quotient (IQ) losses 
from mercury and lead exposure, non-market benefits of water quality 
improvements, and the protection of threatened and endangered species. 
EPA also monetized the benefits of avoided impoundment failures, 
including both ``catastrophic'' failures and smaller-volume releases. 
One example of a severe impoundment failure is the Dan River Steam 
Station failure which occurred in 2014, when a stormwater drainage pipe 
under the inactive surface impoundments at the Dan River Steam Station 
caused the inadvertent release of 39,000 tons of CCR directly into the 
nearby Dan River. The result high-end estimate of the costs of this 
impoundment failure is $300 million.
    The RIA also describes a number of important benefits that cannot 
currently be quantified of monetized due to data limitations or 
limitations in current methodologies. These benefits include reducing 
the baseline risk of unit leakage and failure attributable to climate-
change driven severe weather events. Many legacy CCR surface 
impoundments and CCRMU are situated close to rivers or are located 
along the coast. These units are vulnerable to inland or coastal 
flooding, which may occur at an increased frequency due to the effects 
of climate change. Flooding events may cause these units to overtop or 
catastrophically collapse, releasing CCR into the environment, exposing 
nearby communities to toxic contamination and necessitating potentially 
costly cleanup and remediation. EPA has identified 36 legacy CCR 
impoundments at medium or high risk from climate change driven 
flooding, and 27 CCRMU at medium or high risk from climate change 
driven flooding.
    Another set of benefits outside the scope of quantification include 
reducing the instance of negative human health impacts such as 
cardiovascular mortality, neurological effects, and cancers (separate 
from the quantified cancer benefits) brought on by exposure to toxins 
found in coal ash. Either through leaking impoundment sites or release 
events, many pollutants from legacy CCR surface impoundments are likely 
to contaminate nearby water bodies, affecting surface waters, local 
fish populations, and drinking water reservoirs. Because known 
transport pathways exist between these release events and human heath 
endpoints, EPA expects the proposed rule to cause risk reductions for 
various categories that are not yet quantifiable. Toxins such as 
thallium, molybdenum, and lithium, while all present in CCR, lack the 
data to create dose-response relationships between ingestion rates and 
specific health endpoints, and thus precludes EPA from quantifying 
associated benefits.
    The RIA describes several surface water quality benefits such as 
the improved health of ecosystems proximate to CCR disposal units, and 
the avoided costs of treating public drinking water impacted by CCR 
contamination. EPA expects leakages or releases of effluent from any 
CCR surface impoundment site to contaminate nearby surface waters and 
environments. Introduction of arsenic, selenium, and other heavy metals 
associated with CCR surface impoundment contents are shown to 
accumulate in sediments of nearby stream and lake beds, posing risks 
and injury to organisms and consequently ecosystems. Although surface 
waters are broadly protected from high levels of contaminants under 
EPA's regulations and Water Quality Criteria (WQC), complex 
interactions from trace amounts of heavy metals and other toxins known 
to be released from legacy CCR surface impoundment sites have displayed 
measurable impact to aquatic animals and ecosystems.\81\
---------------------------------------------------------------------------

    \81\ Brandt, Jessica E., et al. ``Beyond selenium: coal 
combustion residuals lead to multielement enrichment in receiving 
lake food webs.'' Environmental science & technology 53.8 (2019): 
4119-4127.
---------------------------------------------------------------------------

    The proposed rule may result in avoided drinking water treatment 
costs and drinking water quality improvements at public water systems. 
First, by reducing the risk of CCR leakage events and impoundment 
failures, the proposed rule will help avoid costs of water quality 
treatment at public intake sources. Second, by preventing release 
events the proposed rule has the potential to reduce the incidence of 
eutrophication in source waters for public drinking supplies. 
Eutrophication is primarily caused by an overabundance of nitrogen and 
phosphorus. It causes foul tastes and odors, which require additional 
treatment, and commensurate expenditure, to remove.
    The RIA discusses potential impacts on the market for the 
beneficial use of CCR as a substitute for virgin materials. Future uses 
of CCR are unknown. Research on the recovery of rare earth elements and 
yttrium from coal fly ash is ongoing but currently only at laboratory 
scale. It is possible that in the future, the availability of 
additional CCR may reach an equilibrium price that encourages demand, 
particularly as coal plants retire and the supply of ``new'' CCR falls. 
However, the quality of CCR in legacy CCR surface impoundments and 
CCRMU may limit their value. Older, closed impoundments or other CCR 
storage areas are less likely to have CCR material of a known and 
reliable composition.
    The RIA also discusses potential reductions in fugitive dust 
emanating from legacy CCR surface impoundments, which will benefit 
fence line communities by reducing the amount of resuspended ash from 
legacy CCR surface impoundments that could otherwise lead to 
respiratory health hazards for communities surrounding a given legacy 
surface impoundment.
    The RIA discusses the benefits of improved property values near 
closed and remediated sites. Neighborhoods located near hazardous waste 
sites often experience depressed property values due to health risks 
posed by contaminant exposure pathways, potential reductions in 
ecological services, unsightly aesthetics of the

[[Page 32030]]

disposal unit site, and potential stigma associated with proximity to a 
disposal site. Almost a million households, and over 2.5 million people 
are located within 3 miles of legacy CCR surface impoundments and 
CCRMU. Approximately 75,000 households and 200,000 people are located 
within a mile. Improvements in home values resulting from the proposed 
rule have the potential to bestow welfare gains to homeowners located 
near legacy CCR units and CCR management units.
    The RIA also discusses the value of reusing land formerly occupied 
by legacy CCR surface impoundments, and CCRMU. Once legacy CCR surface 
impoundments and CCRMU are closed by removal, or landfills are properly 
capped, or corrective action activities are completed, the land is more 
likely to move into alternative, economically productive purposes. For 
example, these land reuse projects might include industrial 
redevelopment or implementation of green energy generation which can 
utilize the existing electricity grid infrastructure.
    Finally, based on the demographic composition and environmental 
conditions of communities within one and three miles of legacy CCR 
surface impoundments, these proposals will reduce existing 
disproportionate and adverse effects on economically vulnerable 
communities, as well as those that currently face environmental 
burdens. For example, in Illinois the population living within 1 mile 
of legacy CCR surface impoundment sites is over three times as likely 
compared to the state average to have less than a high school education 
(35.66% compared to 10.10%, see RIA exhibit ES.14), and that population 
already experiences higher than average exposures to particulate 
matter, ozone, diesel emissions, lifetime air toxics cancer risks, and 
proximity to traffic, Superfund sites, Risk Management Plan sites, and 
hazardous waste facilities (see RIA exhibit ES.15).
    The RIA also discusses the interaction of the CCR rules with Air 
rules governing emissions at power plants. Following on the significant 
progress EPA has made over many decades to reduce dangerous pollution 
from coal-fired electric utilities' stack emissions and effluents, this 
proposed rule will help EPA further ensure that the communities and 
ecosystems closest to coal facilities are sufficiently protected from 
harm from groundwater contamination, surface water contamination, 
fugitive dust, floods and impoundment overflows, and threats to 
wildlife. The volume and toxicity of CCR at many sites persisted or 
increased over past decades even as coal-fired units' air and water 
emissions decreased, and this proposed rule will help EPA fulfill the 
promise of substantial public health and welfare gains from its full 
suite of regulations aimed at reducing the harms from coal-combustion 
pollution.
    As noted previously, EPA establishes the requirements under RCRA 
sections 1008(a)(3) and 4004(a) without taking cost into account. See, 
USWAG, 901 F.3d at 448-49. Although EPA has accordingly designed its 
proposal based on its statutory factors and court precedent and has not 
relied on this benefit-cost analysis in the selection of its proposed 
alternative, EPA believes that after considering all unquantified and 
distributional effects, the public health and welfare gains that will 
result from the proposed alternative would justify the rule's costs.
    Under section 3(f)(1) of Executive Order 12866, this action is 
considered a significant action.

VII. Statutory and Executive Order Reviews

    Additional information about these statutes and Executive Orders 
can be found at https://www.epa.gov/laws-regulations/laws-and-executive-orders.

A. Executive Order 12866: Regulatory Planning and Review and Executive 
Order 13563: Improving Regulation and Regulatory Review

    Under section 3(f)(1) of Executive Order 12866, this action is a 
significant regulatory action that was submitted to the Office of 
Management and Budget (OMB) for review. Any changes made in response to 
recommendations received as part Executive Order 12866 review have been 
documented in the docket. EPA prepared an analysis of the potential 
costs and benefits associated with this action. This analysis, 
Regulatory Impact Analysis: Hazardous and Solid Waste Management 
System: Disposal of Coal Combustion Residuals from Electric Utilities; 
Legacy CCR Surface Impoundments, is available in the docket. and is 
briefly summarized in section VII.

B. Paperwork Reduction Act (PRA)

    The information collection activities in this proposed rule have 
been submitted for approval to the Office of Management and Budget 
(OMB) under the PRA. The Information Collection Request (ICR) document 
that the EPA prepared has been assigned EPA ICR number 2761.01. You can 
find a copy of the ICR in the docket for this rule, and it is briefly 
summarized here.
    The proposed rule requires legacy CCR surface impoundments to 
comply with the reporting and recordkeeping requirements already in 
place for regulated CCR units. Many of these requirements are one-time 
requirements that will occur soon after the promulgation of the rule, 
while several are ongoing. The proposed rule also requires legacy CCR 
surface impoundments to submit an applicability report, unique to this 
universe of units, which will provide stakeholders with essential site 
characteristic and contact information for the unit.
    Respondents/affected entities: Inactive coal fired electric utility 
plants with inactive CCR surface impoundments (legacy CCR surface 
impoundments), coal-fired electric utility plants with CCRMU, and coal-
fired electric utility plants with landfills already subject to 
regulation under the 2015 final CCR rule, but which have waste in 
contact with groundwater.
    Respondent's obligation to respond: The recordkeeping, 
notification, and posting are mandatory as part of the minimum national 
criteria promulgated under Sections 1008(a), 2002(a), 4004, and 4005(a) 
and (d) of RCRA.
    Estimated number of respondents: 273.
    Frequency of response: one-time and annually.
    Total estimated burden: 70,700 hours (per year). Burden is defined 
at 5 CFR 1320.3(b).
    Total estimated cost: $24.4 million (per year), includes $20.4 
million annualized capital or operation & maintenance costs.
    An agency may not conduct or sponsor, and a person is not required 
to respond to, a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for the 
EPA's regulations in 40 CFR are listed in 40 CFR part 9.
    Submit your comments on the Agency's need for this information, the 
accuracy of the provided burden estimates and any suggested methods for 
minimizing respondent burden to the EPA using the docket identified at 
the beginning of this rule. The EPA will respond to any ICR-related 
comments in the final rule. You may also send your ICR-related comments 
to OMB's Office of Information and Regulatory Affairs using the 
interface at www.reginfo.gov/public/do/PRAMain. One may find this 
particular information collection by selecting ``Currently under 
Review--Open for Public Comments'' or by using the search function. OMB 
must receive comments no later than July 17, 2023.

[[Page 32031]]

C. Regulatory Flexibility Act (RFA)

    I certify that this action will not have a significant economic 
impact on a substantial number of small entities under the RFA. The 
small entities subject to the requirements of this action are owners 
and operators of coal fired electric utility plants in NAICS code 
221112 and firms that own property on which an inactive/retired coal 
fired power plant is located. The Agency has identified 11 small 
entities subject to the proposed rule. The Agency estimates that the 
average annual cost to a small entity that owns CCRMU will be 
approximately $2.8 million, and the average annual cost to a small 
entity that owns legacy CCR surface impoundments will be about $2.1 
million. EPA makes two assumptions about how small entities will comply 
with the rule. First, EPA assumes that the units owned by small 
entities will all require corrective action, and will undergo closure 
by removal. Second, EPA assumes that small entities will not be able to 
pass on any compliance costs to ratepayers. These assumptions, in EPA's 
opinion, constitute a high-end scenario. Eight small entities are 
estimated to own CCRMU, for an annual cost of approximately $23 
million. Three small entities are estimated to own legacy CCR surface 
impoundments for an annual cost of approximately $6.5 million. In total 
small entities are estimated to incur approximately $29.5 million in 
annual costs. The Agency has determined that one small entity may 
experience an impact above 1% of annual revenues but below 3% of annual 
revenues, and one small entity may experience an impact greater than 3% 
of annual revenues. Details of this analysis are presented in the 
Regulatory Impact Analysis, which can be found in the docket for this 
action.

D. Unfunded Mandates Reform Act (UMRA)

    This action contains a federal mandate under UMRA, 2 U.S.C. 1531-
1538, that may result in expenditures of $100 million or more for 
state, local and tribal governments, in the aggregate, or the private 
sector in any one year. Accordingly, the EPA has prepared a written 
statement required under section 202 of UMRA. The statement is included 
in the docket for this action and briefly summarized here.
    The RIA estimates that the proposed rule may affect 127 legacy CCR 
surface impoundments at 59 facilities, 134 CCRMU at 82 facilities, and 
29 landfills already regulated under the 2015 final rule. The proposed 
rule will extend the existing requirements of the 2015 CCR final rule, 
found in 40 CFR part 257, subpart D, to these units.
    In preparing the 2015 CCR final rule, and consistent with the 
intergovernmental consultation provisions of section 204 of the UMRA, 
EPA initiated pre-proposal consultations with governmental entities 
affected by the rule. In developing the regulatory options for the 2015 
CCR Rule, EPA consulted with small governments according to EPA's UMRA 
interim small government consultation plan developed pursuant to 
section 203 of UMRA. The details of this consultation can be found in 
the preamble to the 2015 CCR final rule. Consistent with section 205 of 
UMRA, EPA identified and considered a reasonable number of regulatory 
alternatives, and adopted the least-costly approach (i.e., a modified 
version of the ``D Prime'' least costly approach presented in the 2010 
proposed CCR rule). The proposed rule merely extends the provisions of 
the 2015 final rule to three additional classes of facilities.
    This action is not subject to the requirements of section 203 of 
UMRA because it contains no regulatory requirements that might 
significantly or uniquely affect small governments. The threshold 
amount established for determining whether regulatory requirements 
could significantly affect small governments is $100 million annually. 
The RIA estimates annual average costs of $5 million total for the two 
local governments identified as owning units subject to the proposed 
rule. These estimates are well below the $100 million annual threshold 
established under UMRA. There are no known tribal owner entities of 
facilities that would incur substantial direct costs under the proposed 
rule.

E. Executive Order 13132: Federalism

    This action does not have federalism implications. It will not have 
substantial direct effects on the states, on the relationship between 
the national government and the states, or on the distribution of power 
and responsibilities among the various levels of government.

F. Executive Order 13175: Consultation and Coordination With Indian 
Tribal Governments

    This action does not have tribal implications as specified in 
Executive Order 13175. For the ``Final Rule: Hazardous and Solid Waste 
Management System; Disposal of Coal Combustion Residuals from Electric 
Utilities'' published April 17, 2015 (80 FR 21302), EPA identified 
three of the 414 coal-fired electric utility plants (in operation as of 
2012) as being located on tribal lands. To the extent that these plants 
contain CCRMU subject to the proposed rule, the impacts to tribes will 
be limited to document review and walking the site. As these are not 
substantial direct costs, this action does not impose substantial 
direct compliance costs or otherwise have a substantial direct effect 
on one or more Indian tribes, to the best of EPA's knowledge. Neither 
will it have substantial direct effects on the relationship between the 
Federal Government and Indian tribes, or on the distribution of power 
and responsibilities between the Federal Government and Indian tribes. 
Thus, Executive Order 13175 does not apply to this action.

G. Executive Order 13045: Protection of Children From Environmental 
Health Risks and Safety Risks

    This action is subject to E.O. 13045 (62 FR 19885, April 23, 1997) 
because it is a significant regulatory action under section 3(f)(1) of 
E.O. 12866, and EPA believes that the environmental health or safety 
risks addressed by this action may have a disproportionate effect on 
children. Accordingly, EPA evaluated the environmental health or safety 
effects of CCR constituents of potential concern on children. The 
results of this evaluation are contained in the Human and Ecological 
Risk Assessment of Coal Combustion Wastes available in the docket for 
this action.
    As ordered by E.O. 13045 Section 1-101(a), EPA identified and 
assessed environmental health risks and safety risks that may 
disproportionately affect children in the revised risk assessment. 
Pursuant to U.S. EPA's Guidance on Selecting Age Groups for Monitoring 
and Assessing Childhood Exposures to Environmental Contaminants, 
children are divided into seven distinct age cohorts: 1 to <2 yr, 2 to 
<3 yr, 3 to <6 yr 6 to <11 yr, 11 to <16 yr, 16 to <21 yr, and infants 
(<1 yr). Using exposure factors for each of these cohorts, EPA 
calculated cancer and non-cancer risk results in both the screening and 
probabilistic phases of the assessment. In general, risks to infants 
tended to be higher than other childhood cohorts, and also higher than 
risks to adults. However, for drinking water cancer risks, the longer 
exposures for adults led to the highest risks. Screening risks exceeded 
EPA's human health criteria for children exposed to contaminated air, 
soil, and food resulting from fugitive dust emissions and run-off. 
Similarly, 90th percentile child cancer and non-cancer risks exceeded 
the human health

[[Page 32032]]

criteria for the groundwater to drinking water pathway under the full 
probabilistic analysis (Table 5-17 in the Human and Ecological Risk 
Assessment of Coal Combustion Wastes). The closure, groundwater 
monitoring and corrective action required by the rule will reduce risks 
from currently unregulated legacy CCR surface impoundments, and waste 
management units. Thus, EPA believes that this rule will be protective 
of children's health.
    In general, because the pollution control requirements under the 
CCR rule will reduce health and environmental exposure risks at all 
coal-fired electric utility plants, the CCR rule is not expected to 
create additional or new risks to children.

H. Executive Order 13211: Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution or Use

    This action is not a ``significant energy action'' because it is 
not likely to have a significant adverse effect on the supply, 
distribution or use of energy. Because the proposed rule addresses 
management of CCR and pertains solely to inactive CCR units (legacy CCR 
surface impoundments at inactive facilities and CCR management units at 
facilities already regulated under the 2015 CCR rule), this proposed 
rule will have no effect on the production of crude oil, coal, fuel, or 
natural gas. In addition, the proposed rule will have no direct effect 
on electricity production, generating capacity, or on foreign imports 
or exports of energy.
    Electricity price effects on the price of energy are only possible 
because in some cases, utilities may attempt to pass the costs of 
managing CCR under the proposed rule on to ratepayers in the form of 
increased electricity rates through Public Utility Commissions (PUCs). 
As a result, the proposed rule may indirectly affect electricity prices 
within the energy sector. To estimate what the electricity price 
effects of this proposed rule may be on a national level, EPA compared 
the expected costs of this rule to the expected costs and effects 
resulting from three previously conducted IPM runs for three previous 
RIAs, the 2015 CCR Rule, the 2015 ELG Rule (which included the costs of 
the 2015 CCR Rule in its baseline), and the 2019 ELG Rule, which was a 
deregulatory rule. Extrapolating from these IPM runs, EPA estimates 
that the effect of the current action on electricity prices will be 
between 0.042% and 0.125%. Since these effects fall below the 1% 
threshold, EPA concludes that this rule is not expected to generate 
significant adverse energy effects. The full energy impacts analysis is 
available in the Regulatory Impact Analysis that accompanies this 
action.

I. National Technology Transfer and Advancement Act (NTTAA)

    This rulemaking involves technical standards. EPA has decided to 
use the following technical standards in this rule: (1) RCRA Subpart D, 
Section 257.70 liner design criteria for new CCR landfills and any 
lateral expansion of a CCR landfill includes voluntary consensus 
standards developed by ASTM International and EPA test methods such as 
SW-846, (2) Section 257.71 liner design criteria for existing CCR 
surface impoundments includes voluntary consensus standards developed 
by ASTM International and EPA test methods such as SW-846, (3) Section 
257.72 liner design criteria for new CCR surface impoundments and any 
lateral expansion of a CCR surface impoundment includes voluntary 
consensus standards developed by ASTM International and EPA test 
methods such as SW-846, and (4) Section 257.73 structural stability 
standards for new and existing surface impoundments use the ASTM D 698 
and 1557 standards for embankment compaction.

J. Executive Order 12898: Federal Actions To Address Environmental 
Justice in Minority Populations and Low-Income Populations

    Executive Order 12898 (59 FR 7629, February 16, 1994) directs 
federal agencies, to the greatest extent practicable and permitted by 
law, to make environmental justice (EJ) part of their mission by 
identifying and addressing, as appropriate, disproportionately high and 
adverse human health or environmental effects of their programs, 
policies, and activities on communities with environmental justice 
concerns.
    EPA believes that the human health or environmental conditions that 
exist prior to this action result in or have the potential to result in 
disproportionate and adverse human health or environmental effects on 
communities with environmental justice concerns.
    EPA conducted a demographic screening analysis for all legacy CCR 
surface impoundments and CCRMU to determine the composition of 
populations living within one and three miles of facilities with these 
units. Specifically, EPA looked at the percentages of the relevant 
populations that are identified as minority/people of color, households 
below the federal poverty level, population with less than high school 
education (among those 25 years and older), and populations 
characterized by linguistic isolation. EPA chose to look at radii of 
one and three miles because they represent the areas most likely to be 
affected by groundwater contamination from legacy CCR surface 
impoundments and CCRMU. EPA compared the demographic profile within 
these radii to national averages to assess the extent to which 
marginalized groups are disproportionately affected by contamination 
from legacy CCR surface impoundments and CCRMU in the baseline. EPA 
found that the following demographic and socioeconomic indicators were 
more highly represented within one and three miles of sites containing 
legacy CCR surface impoundments than the U.S. national averages: 
minority/people of color, Black population, Native American population, 
Hispanic ethnicity, households below the poverty level, less than high 
school education, and linguistic isolation. EPA found that the 
following demographic and socioeconomic indicators were more highly 
represented within one and three miles of CCRMU: Black population, 
``Other'' racial groups, households below the poverty level, and less 
than high school education. EPA also compared a subset of three 
population indicators, minority status, less than high school education 
and linguistic isolation, around legacy CCR surface impoundments and 
CCRMU against state level population characteristics. In eight of the 
25 states (32%) containing legacy CCR surface impoundments affected by 
the proposed rule, at least one of these three demographic indicators 
for populations within one mile of the facility was above twice the 
state average value. In five of the 28 states (18%) containing CCRMU 
affected by the proposed rule, at least one of the three demographic 
indicators for populations within one mile of the facility was above 
twice the state average value.
    EPA also examined the cumulative environmental impacts that exist 
around facilities in the affected universe. EPA looked at the following 
eight environmental indicators, PM 2.5, O3, Diesel PM, Lifetime Cancer 
Risk, Traffic Proximity, National Priorities List (NPL) Proximity, Risk 
Management Plan (RMP) Proximity, and Transportation Storage and 
Disposal Facility (TSDF) proximity within one mile of facilities in the 
affected universe. Because environmental indicators are not available 
at the national level, EPA confined this analysis to states where at 
least one facility registered twice the

[[Page 32033]]

state average on any of the eight environmental indicators. Nine states 
contain such facilities, and in six of them at least half of the 
environmental indicators within a mile of facilities containing legacy 
units were higher than state averages. At the state level, therefore, 
environmental issues seem to cluster, uniquely impacting communities 
living within a mile of legacy and management units.
    Based on the results of these demographic screening analyses, EPA 
believes that the human health or environmental conditions that exist 
prior to this action result in or have the potential to result in 
disproportionate and adverse human health or environmental effects on 
communities with environmental justice concerns.
    EPA believes that this action is likely to reduce existing 
disproportionate and adverse effects on communities with environmental 
justice concerns. Neighborhoods located near legacy CCR surface 
impoundments and CCR management units are disproportionately occupied 
by communities with environmental justice concerns. These vulnerable 
communities face risks of impoundment failure, groundwater 
contamination, and fugitive air emissions. If such failures or 
contamination occur, nearby residents will face risks to their health, 
both cancer and noncancer. Other risks include damage to ecosystem 
services and environmental amenities. These communities are likely to 
face existing environmental burdens that put them at greater cumulative 
risk from the environmental impacts associated with proximity to legacy 
units. EPA believes that the proposed rule is likely to incrementally 
reduce baseline disproportionate and adverse effects on communities 
with environmental justice concerns by requiring closure and corrective 
action at legacy CCR surface impoundments and CCRMU, thereby reducing 
the risks of exposure to contamination from CCR faced by these 
populations. The analyses above examining the demographic composition 
and environmental conditions of communities within one and three miles 
of legacy CCR surface impoundments and CCRMU highlight the higher 
potential incidence of EJ issues in more demographically vulnerable 
communities. They demonstrate that the proposed rule is likely to 
improve conditions for nearby communities from the baseline, as these 
communities are more likely than the national average to be more 
vulnerable to environmental harms due to their demographics and 
economic vulnerability and are currently facing existing environmental 
burdens. It is important to note that proximity to traffic could remain 
a significant EJ issue and in fact be exacerbated by the proposed rule 
if removal of CCR from plants with legacy units is undertaken using 
heavy-duty vehicles and routes that run through residential areas. EJ 
concerns related to traffic will need to be assessed at a site-by-site 
level in conversation with nearby communities as EPA implements the 
proposed rule.
    The information supporting this Executive Order review is contained 
in the accompanying Regulatory Impact Analysis, which can be found in 
the docket for this action.

List of Subjects in 40 CFR Part 257

    Environmental protection, Beneficial use, Coal combustion products, 
Coal combustion residuals, Coal combustion waste, Disposal, Hazardous 
waste, Landfill, Surface impoundment.

Michael S. Regan,
Administrator.

    For the reasons set out in the preamble, EPA proposes to amend 40 
CFR part 257 as follows:

PART 257--CRITERIA FOR CLASSIFICATION OF SOLID WASTE DISPOSAL 
FACILITIES AND PRACTICES

0
1. The authority citation for part 257 continues to read as follows:

    Authority: 42 U.S.C. 6907(a)(3), 6912(a)(1), 6944, 6945(a) and 
(d); 33 U.S.C. 1345(d) and (e).

0
2. Amend Sec.  257.1 by revising paragraph (c)(12) to read as follows:

Sec.  257.1  Scope and purpose.

* * * * *
    (c) * * *
    (12) Except as otherwise specifically provided in subpart D of this 
part, the criteria in subpart A of this part do not apply to CCR 
landfills, CCR surface impoundments, lateral expansions of CCR units, 
and CCR management units, as those terms are defined in subpart D of 
this part. Such units are instead subject to subpart D of this part.

Subpart D [AMENDED]

0
3. Amend subpart D by remove the phrase ``Web site'' and adding in its 
place the word ``website'' everywhere it appears.
0
4. Amend Sec.  257.50 by revising paragraph (c), (d), and (e) to read 
as follows:

Sec.  257.50  Scope and purpose.

* * * * *
    (c) This subpart also applies to inactive CCR surface impoundments 
at active electric utilities or independent power producers, regardless 
of how electricity is currently being produced at the facility.
    (d) This subpart applies to CCR management units located at active 
or inactive facilities with a CCR unit.
    (e) This subpart applies to electric utilities or independent power 
producers that have ceased producing electricity prior to October 19, 
2015 and that have a legacy CCR surface impoundment.
* * * * *
0
5. Revise Sec.  257.52 to read as follows:

Sec.  257.52  Applicability of other regulations.

    (a) Compliance with the requirements of this subpart does not 
affect the need for the owner or operator of a CCR landfill, CCR 
surface impoundment, lateral expansion of a CCR unit, or CCR management 
unit to comply with all other applicable federal, state, tribal, or 
local laws or other requirements.
    (b) Any CCR landfill, CCR surface impoundment, lateral expansion of 
a CCR unit, or CCR management unit continues to be subject to the 
requirements in Sec. Sec.  257.3-1, 257.3-2, and 257.3-3.
0
6. Amend Sec.  257.53 by:
0
a. Revising the definitions of ``Active life or in operation'', 
``Active portion'', ``Closed'', and ``CCR landfill or landfill'';
0
b. Adding the definition of ``CCR management unit'' in alphabetical 
order;
0
c. Revising the definitions of ``CCR unit'';
0
d. Adding the definition of ``Inactive CCR landfill'' in alphabetical 
order;
0
e. Revising the definition of ``Inactive CCR surface impoundment'';
0
f. Adding the definitions of ``Inactive facility or inactive electric 
utility or independent power producer'' and ``Legacy CCR surface 
impoundment'' in alphabetical order; and
0
g. Revising the definitions of ``Operator'', ``Owner'', ``Qualified 
person'', ``Qualified professional engineer'', ``State Director'', 
``Technically feasible or feasible'', ``Technically infeasible or 
infeasible'', and ``Waste boundary''.
    The revisions and additions read as follows:

Sec.  257.53  Definitions.

* * * * *
    Active life or in operation means the period of operation beginning 
with the initial placement of CCR in the CCR unit or CCR management 
unit and ending at completion of closure activities in accordance with 
Sec.  257.102.

[[Page 32034]]

    Active portion means that part of the CCR unit or CCR management 
unit that has received or is receiving CCR or non-CCR waste and that 
has not completed closure in accordance with Sec.  257.102.
* * * * *
    Closed means placement of CCR in a CCR unit or CCR management unit 
has ceased, and the owner or operator has completed closure of the CCR 
unit or CCR management unit in accordance with Sec.  257.102 and has 
initiated post-closure care in accordance with Sec.  257.104.
* * * * *
    CCR landfill or landfill means an area of land or an excavation 
that receives CCR and which is not a surface impoundment, a CCR 
management unit, an underground injection well, a salt dome formation, 
a salt bed formation, an underground or surface coal mine, or a cave. 
For purposes of this subpart, a CCR landfill also includes sand and 
gravel pits and quarries that receive CCR, CCR piles, and any practice 
that does not meet the definition of a beneficial use of CCR.
    CCR management unit means any area of land on which any non-
containerized accumulation of CCR is received, placed, or otherwise 
managed at any time, that is not a CCR unit. This includes inactive CCR 
landfills and CCR units that closed prior to October 17, 2015.
* * * * *
    CCR unit means any CCR landfill, CCR surface impoundment, or 
lateral expansion of a CCR unit, or a combination of more than one of 
these units, based on the context of the paragraph(s) in which it is 
used. This term includes both new and existing units, unless otherwise 
specified. This term does not include CCR management units.
* * * * *
    Inactive CCR landfill means an area of land or an excavation that 
contains CCR but that no longer receives CCR on or after the effective 
date of the final rule and that is not a surface impoundment, an 
underground injection well, a salt dome formation, a salt bed 
formation, an underground or surface coal mine, or a cave. For purposes 
of this subpart, this term also includes sand and gravel pits that 
received CCR, and abandoned CCR piles.
    Inactive CCR surface impoundment means a CCR surface impoundment 
located at an active facility that no longer receives CCR on or after 
October 19, 2015, and still contains both CCR and liquids on or after 
October 19, 2015.
    Inactive facility or inactive electric utility or independent power 
producer means any facility with a legacy CCR surface impoundment 
subject to the requirements of this subpart that ceased operation prior 
to October 19, 2015. An electric utility or independent power producer 
is no longer in operation if it has ceased generating electricity 
provided to electric power transmission systems or to electric power 
distribution systems before October 19, 2015. An inactive facility does 
not include an off-site disposal facility that ceased operation prior 
to October 19, 2015.
* * * * *
    Legacy CCR surface impoundment means a CCR surface impoundment that 
no longer receives CCR but contained both CCR and liquids on or after 
October 19, 2015, and that is located at an inactive electric utility.
* * * * *
    Operator means the person(s) responsible for the overall operation 
of a CCR unit or CCR management unit. This term includes those 
person(s) or parties responsible for disposal or otherwise actively 
engaged in the solid waste management of CCR. It also includes those 
responsible for directing or overseeing groundwater monitoring, closure 
or post-closure activities at a CCR unit or CCR management unit.
* * * * *
    Owner means the person(s) who owns a CCR unit or CCR management 
unit or part of a CCR unit or CCR management unit, or a facility, 
whether in full or in part.
* * * * *
    Qualified person means a person or persons trained to recognize 
specific appearances of structural weakness and other conditions which 
are disrupting or have the potential to disrupt the operation or safety 
of the CCR unit or CCR management unit by visual observation and, if 
applicable, to monitor instrumentation.
    Qualified professional engineer means an individual who is licensed 
by a state as a Professional Engineer to practice one or more 
disciplines of engineering and who is qualified by education, technical 
knowledge and experience to make the specific technical certifications 
required under this subpart. Professional engineers making these 
certifications must be currently licensed in the state where the CCR 
unit(s) or CCR management unit is located.
* * * * *
    State Director means the chief administrative officer of the lead 
state agency responsible for implementing the state program regulating 
disposal in CCR landfills, CCR surface impoundments, all lateral 
expansions of a CCR unit, and CCR management units.
* * * * *
    Technically feasible or feasible means possible to do in a way that 
would likely be successful.
    Technically infeasible or infeasible means not possible to do in a 
way that would likely be successful.
* * * * *
    Waste boundary means a vertical surface located at the 
hydraulically downgradient limit of the CCR unit or CCR management 
unit. The vertical surface extends down into the uppermost aquifer.
0
7. Amend Sec.  257.61 by revising the introductory text of paragraph 
(a) to read as follows:

Sec.  257.61  Wetlands.

    (a) New CCR landfills, existing and new CCR surface impoundments, 
and all lateral expansions of CCR units must not be located in 
wetlands, as defined in Sec.  230.41(a) of this chapter, unless the 
owner or operator demonstrates by the dates specified in paragraph (c) 
of this section that the CCR unit meets the requirements of paragraphs 
(a)(1) through (5) of this section.
* * * * *
0
8. Add Sec.  257.75 to subpart D to read as follows:

Sec.  257.75  Requirements for identifying CCR management units.

    (a) Applicability. The requirements of this section apply to owners 
and operators of active or inactive facilities with one or more CCR 
unit(s).
    (b) Facility evaluation. Upon the effective date of the final rule, 
the owner or operator of an active facility or inactive facility with 
one or more CCR unit(s) must initiate a facility evaluation to identify 
all CCR management units at the facility. At a minimum, the presence or 
absence of CCR management units at the facility must be confirmed and 
documented through a thorough evaluation of available records that 
contain the information needed to prepare the Facility Evaluation 
Report required by paragraph (c) of this section. The facility 
evaluation must include a physical inspection of the facility. Where 
necessary, the physical inspection must additionally include field 
investigation activities to fill data gaps, such as conducting 
exploratory soil borings, geophysical assessments, or any other similar 
physical investigation activities to establish the location and 
boundaries of identified CCR management units, and to affirmatively 
rule out other areas of potential CCR placement at the facility that 
were identified during the information

[[Page 32035]]

review. The facility evaluation must identify all CCR management units 
at the facility regardless of when the CCR management unit came into 
existence.
    (c) Facility evaluation report. No later than 3 months after the 
effective date of the final rule, the owner or operator of an active or 
inactive facility that contains CCR units regulated under this subpart 
must prepare a Facility Evaluation Report, which shall contain, to the 
extent available, the information specified in paragraphs (c)(1) 
through (13) of this section. The owner or operator has prepared the 
Facility Evaluation Report when the report has been placed in the 
facility's operating record as required by Sec.  257.105(f)(25).
    (1) The name and address of the person(s) owning and operating the 
facility; the unit name associated with any CCR unit and CCR management 
unit at the facility; and the identification number of each CCR unit 
and CCR management unit if any have been assigned by the state.
    (2) The location of any CCR management unit identified on the most 
recent U.S. Geological Survey (USGS) 7 1-2 minute or 15-minute 
topographic quadrangle map, or a topographic map of equivalent scale if 
a USGS map is not available. The location of each CCR unit at the 
facility must also be identified.
    (3) A statement of the purpose(s) for which each CCR management 
unit at the facility is or was being used.
    (4) A description of the physical and engineering properties of the 
foundation and abutment materials on which each CCR management unit is 
constructed.
    (5) A discussion of any known spills or releases of CCR from each 
CCR management unit and whether the spills or releases were reported to 
state or federal agencies.
    (6) Any record or knowledge of structural instability of each CCR 
management unit.
    (7) Any record or knowledge of groundwater contamination associated 
with each CCR management unit.
    (8) Size of each CCR management unit, including the general 
dimensions and an estimate of the volume of waste contained within the 
unit.
    (9) Dates when each CCR management unit first received CCR and when 
each CCR management unit ceased receiving CCR.
    (10) Specification of all CCR wastes that have been managed in each 
CCR management unit at the facility.
    (11) A narrative description, including any applicable engineering 
drawings or reports of any closure activities that have occurred.
    (12) A narrative that documents the nature and extent of field 
oversight activities and data reviewed as part of the facility 
evaluation process, and that lists all data and information that was 
reviewed indicating the absence of CCR management units at the 
facility.
    (13) Any supporting information used to identify and evaluate CCR 
management units at the facility, including but not limited to any 
construction diagrams, engineering drawings, permit documents, 
wastestream flow diagrams, aerial photographs, satellite images, 
historical facility maps, any field or analytical data, groundwater 
monitoring data or reports, inspection reports, documentation of 
interviews with current or former facility workers, and other documents 
used to identify and assess CCR management units at the facility.
    (d) The owner or operator of any facility regulated under this 
subpart must obtain a certification from a qualified professional 
engineer stating that the Facility Evaluation Report meets the 
requirements of paragraph (c) of this section.
    (e) The owner or operator of any facility regulated under this 
subpart must certify the Facility Evaluation Report required by 
paragraph (c) of this section with the following statement signed by 
the owner or operator or an authorized representative:

    I certify under penalty of law that I have personally examined 
and am familiar with the information submitted in this demonstration 
and all attached documents, and that, based on my inquiry of those 
individuals immediately responsible for obtaining the information, I 
believe that the submitted information is true, accurate, and 
complete. I am aware that there are significant penalties for 
submitting false information, including the possibility of fine and 
imprisonment.

    (f) The owner or operator of any facility regulated under this 
subpart that does not contain any CCR management unit must submit a 
Facility Evaluation Report documenting the steps taken during the 
facility evaluation to determine the absence of any CCR management 
unit. The Facility Evaluation Report must include the certifications 
required under paragraphs (d) and (e) of this section.
    (g) The owner or operator of the CCR management unit must comply 
with the recordkeeping requirements specified in Sec.  257.105(f)(25), 
the notification requirements specified in Sec.  257.106(f)(24), and 
the internet requirements specified in Sec.  257.107(f)(24).
0
9. Amend Sec.  257.80 by revising paragraphs (a), (b) introductory 
text, (b)(6), the first sentence of (c), and (d) to read as follows:

Sec.  257.80  Air criteria.

    (a) The owner or operator of a CCR landfill, CCR surface 
impoundment, any lateral expansion of a CCR unit, or CCR management 
unit must adopt measures that will effectively minimize CCR from 
becoming airborne at the facility, including CCR fugitive dust 
originating from CCR units, roads, and other CCR management and 
material handling activities.
    (b) CCR fugitive dust control plan. The owner or operator of the 
CCR unit or CCR management unit must prepare and operate in accordance 
with a CCR fugitive dust control plan as specified in paragraphs (b)(1) 
through (7) of this section. This requirement applies in addition to, 
not in place of, any applicable standards under the Occupational Safety 
and Health Act.
* * * * *
    (6) Amendment of the plan. The owner or operator subject to the 
requirements of this section may amend the written CCR fugitive dust 
control plan at any time provided the revised plan is placed in the 
facility's operating record as required by Sec.  257.105(g)(1). The 
owner or operator must amend the written plan whenever there is a 
change in conditions that would substantially affect the written plan 
in effect, such as the construction and operation of a new CCR unit.
* * * * *
    (c) Annual CCR fugitive dust control report. The owner or operator 
of a CCR unit or a CCR management unit must prepare an annual CCR 
fugitive dust control report that includes a description of the actions 
taken by the owner or operator to control CCR fugitive dust, a record 
of all citizen complaints, and a summary of any corrective measures 
taken. * * *
    (d) The owner or operator of the CCR unit or a CCR management unit 
must comply with the recordkeeping requirements specified in Sec.  
257.105(g), the notification requirements specified in Sec.  
257.106(g), and the internet requirements specified in Sec.  
257.107(g).
0
10. Amend Sec.  257.90 by:
0
a. Revising paragraph (a);
0
b. Adding paragraph (b)(3); and
0
c. Revising paragraphs (c), (d), (e) introductory text, (e)(1), (e)(6) 
introductory text, (e)(6)(i), (ii), (e)(6)(iii)(B), (e)(6)(iv)(B), (C), 
(D), and (f).
    The revisions and addition read as follows:

[[Page 32036]]

Sec.  257.90  Applicability.

    (a) Applicability. All CCR landfills, CCR surface impoundments, 
lateral expansions of CCR units, and CCR management units are subject 
to the groundwater monitoring and corrective action requirements under 
Sec. Sec.  257.90 through 257.98, except as provided in paragraph (g) 
of this section.
    (b) * * *
    (3) CCR management units. The owner or operator of the CCR 
management unit must be in compliance with the following groundwater 
monitoring requirements by the dates specified in paragraphs (b)(3)(i) 
through (iv) of this section:
    (i) Groundwater monitoring system installation. No later than 6 
months after the effective date of the final rule, install the 
groundwater monitoring system as required by Sec.  257.91.
    (ii) Groundwater monitoring sampling and analysis program. No later 
than 6 months after the effective date of the final rule, develop the 
groundwater sampling and analysis program to include selection of the 
statistical procedures to be used for evaluating groundwater monitoring 
data as required by Sec.  257.93.
    (iii) Initiation of detection monitoring and assessment monitoring. 
No later than 24 months after the effective date of the final rule, be 
in compliance with the following groundwater monitoring requirements:
    (A) Initiate the detection monitoring program to include obtaining 
a minimum of eight independent samples for each background and 
downgradient well, as required by Sec.  257.94(b).
    (B) Begin evaluating the groundwater monitoring data for 
statistically significant increases over background levels for the 
constituents listed in appendix III of this part, as required by Sec.  
257.94.
    (C) Begin evaluating the groundwater monitoring data for 
statistically significant levels over groundwater protection standards 
for the constituents listed in appendix IV of this part as required by 
Sec.  257.95.
    (c) Once a groundwater monitoring system and groundwater monitoring 
program has been established at the CCR unit or a CCR management unit 
as required by this subpart, the owner or operator must conduct 
groundwater monitoring and, if necessary, corrective action throughout 
the active life and post-closure care period of the CCR unit or a CCR 
management unit.
    (d) In the event of a release from a CCR unit or a CCR management 
unit, the owner or operator must immediately take all necessary 
measures to control the source(s) of releases so as to reduce or 
eliminate, to the maximum extent feasible, further releases of 
contaminants into the environment. The owner or operator of the CCR 
unit or a CCR management unit must comply with all applicable 
requirements in Sec. Sec.  257.96, 257.97, and 257.98.
    (e) For existing CCR landfills and existing CCR surface 
impoundments, no later than January 31, 2018, and annually thereafter, 
the owner or operator must prepare an annual groundwater monitoring and 
corrective action report. For new CCR landfills, new CCR surface 
impoundments, and all lateral expansions of CCR units, the owner or 
operator must prepare the initial annual groundwater monitoring and 
corrective action report no later than January 31 of the year following 
the calendar year a groundwater monitoring system has been established 
for such CCR unit as required by this subpart, and annually thereafter. 
For CCR management units, the owner or operator must prepare the 
initial annual groundwater monitoring and corrective action report no 
later than January 31 of the year following the calendar year a 
groundwater monitoring system has been established for such CCR 
management unit as required by this subpart, and annually thereafter. 
For the preceding calendar year, the annual report must document the 
status of the groundwater monitoring and corrective action program for 
the CCR unit or the CCR management unit, summarize key actions 
completed, describe any problems encountered, discuss actions to 
resolve the problems, and project key activities for the upcoming year. 
For the purposes of this section, the owner or operator has prepared 
the annual report when the report is placed in the facility's operating 
record as required by Sec.  257.105(h)(1). At a minimum, the annual 
groundwater monitoring and corrective action report must contain the 
following information, to the extent available:
    (1) A map, aerial image, or diagram showing the CCR unit or the CCR 
management unit and all background (or upgradient) and downgradient 
monitoring wells, to include the well identification numbers, that are 
part of the groundwater monitoring program for the CCR unit or the CCR 
management unit;
* * * * *
    (6) A section at the beginning of the annual report that provides 
an overview of the current status of groundwater monitoring and 
corrective action programs for the CCR unit or the CCR management unit. 
At a minimum, the summary must specify all of the following:
    (i) At the start of the current annual reporting period, whether 
the CCR unit or the CCR management unit was operating under the 
detection monitoring program in Sec.  257.94 or the assessment 
monitoring program in Sec.  257.95;
    (ii) At the end of the current annual reporting period, whether the 
CCR unit or the CCR management unit was operating under the detection 
monitoring program in Sec.  257.94 or the assessment monitoring program 
in Sec.  257.95;
    (iii) * * *
    (B) Provide the date when the assessment monitoring program was 
initiated for the CCR unit or the CCR management unit.
    (iv) * * *
    (B) Provide the date when the assessment monitoring program was 
initiated for the CCR unit or the CCR management unit.
    (C) Provide the date when the public meeting was held for the 
assessment of corrective measures for the CCR unit or the CCR 
management unit; and
    (D) Provide the date when the assessment of corrective measures was 
completed for the CCR unit or the CCR management unit.
* * * * *
    (f) The owner or operator of the CCR unit or the CCR management 
unit must comply with the recordkeeping requirements specified in Sec.  
257.105(h), the notification requirements specified in Sec.  
257.106(h), and the internet requirements specified in Sec.  
257.107(h).
* * * * *
0
11. Amend Sec.  257.91 by revising paragraphs (a) introductory text, 
(a)(1) introductory text, (a)(1)(i), (a)(2), (c)(2), (d), (e)(1), and 
(g) to read as follows:

Sec.  257.91  Groundwater monitoring systems.

    (a) Performance standard. The owner or operator of a CCR unit or a 
CCR management unit must install a groundwater monitoring system that 
consists of a sufficient number of wells, installed at appropriate 
locations and depths, to yield groundwater samples from the uppermost 
aquifer that:
    (1) Accurately represent the quality of background groundwater that 
has not been affected by leakage from a CCR unit or a CCR management 
unit. A determination of background quality may include sampling of 
wells that are not hydraulically upgradient of the CCR management area 
where:
    (i) Hydrogeologic conditions do not allow the owner or operator of 
the CCR unit or the CCR management unit to

[[Page 32037]]

determine what wells are hydraulically upgradient; or
* * * * *
    (2) Accurately represent the quality of groundwater passing the 
waste boundary of the CCR unit or the CCR management unit. The 
downgradient monitoring system must be installed at the waste boundary 
that ensures detection of groundwater contamination in the uppermost 
aquifer. All potential contaminant pathways must be monitored.
* * * * *
    (c) * * *
    (2) Additional monitoring wells as necessary to accurately 
represent the quality of background groundwater that has not been 
affected by leakage from the CCR unit or the CCR management unit and 
the quality of groundwater passing the waste boundary of the CCR unit 
or the CCR management unit.
    (d) The owner or operator of multiple CCR units or CCR management 
units may install a multiunit groundwater monitoring system instead of 
separate groundwater monitoring systems for each CCR unit or CCR 
management unit.
    (1) The multiunit groundwater monitoring system must be equally as 
capable of detecting monitored constituents at the waste boundary of 
the CCR unit or CCR management unit as the individual groundwater 
monitoring system specified in paragraphs (a) through (c) of this 
section for each CCR unit or CCR management unit based on the following 
factors:
    (i) Number, spacing, and orientation of each CCR unit or CCR 
management unit;
    (ii) Hydrogeologic setting;
    (iii) Site history; and
    (iv) Engineering design of the CCR unit or CCR management unit.
    (2) [Reserved]
    (e) * * *
    (1) The owner or operator of the CCR unit or the CCR management 
unit must document and include in the operating record the design, 
installation, development, and decommissioning of any monitoring wells, 
piezometers and other measurement, sampling, and analytical devices. 
The qualified professional engineer must be given access to this 
documentation when completing the groundwater monitoring system 
certification required under paragraph (f) of this section.
* * * * *
    (g) The owner or operator of the CCR unit or the CCR management 
unit must comply with the recordkeeping requirements specified in Sec.  
257.105(h), the notification requirements specified in Sec.  
257.106(h), and the internet requirements specified in Sec.  
257.107(h).
0
12. Amend Sec.  257.93 by revising paragraphs (a) introductory text, 
(c), (d), (f) introductory text, (f)(6), (g)(1), (h), and (j) to read 
as follows:

Sec.  257.93  Groundwater sampling and analysis requirements.

    (a) The groundwater monitoring program must include consistent 
sampling and analysis procedures that are designed to ensure monitoring 
results that provide an accurate representation of groundwater quality 
at the background and downgradient wells required by Sec.  257.91. The 
owner or operator of the CCR unit or the CCR management unit must 
develop a sampling and analysis program that includes procedures and 
techniques for:
* * * * *
    (c) Groundwater elevations must be measured in each well 
immediately prior to purging, each time groundwater is sampled. The 
owner or operator of the CCR unit or the CCR management unit must 
determine the rate and direction of groundwater flow each time 
groundwater is sampled. Groundwater elevations in wells which monitor 
the same CCR management area must be measured within a period of time 
short enough to avoid temporal variations in groundwater flow which 
could preclude accurate determination of groundwater flow rate and 
direction.
    (d) The owner or operator of the CCR unit or the CCR management 
unit must establish background groundwater quality in a hydraulically 
upgradient or background well(s) for each of the constituents required 
in the particular groundwater monitoring program that applies to the 
CCR unit as determined under Sec.  257.94(a) or Sec.  257.95(a). 
Background groundwater quality may be established at wells that are not 
located hydraulically upgradient from the CCR unit or the CCR 
management unit if it meets the requirements of Sec.  257.91(a)(1).
* * * * *
    (f) The owner or operator of the CCR unit or the CCR management 
unit must select one of the statistical methods specified in paragraphs 
(f)(1) through (5) of this section to be used in evaluating groundwater 
monitoring data for each specified constituent. The statistical test 
chosen shall be conducted separately for each constituent in each 
monitoring well.
* * * * *
    (6) The owner or operator of the CCR unit or the CCR management 
unit must obtain a certification from a qualified professional engineer 
or approval from the Participating State Director or approval from EPA 
where EPA is the permitting authority stating that the selected 
statistical method is appropriate for evaluating the groundwater 
monitoring data for the CCR management area. The certification must 
include a narrative description of the statistical method selected to 
evaluate the groundwater monitoring data.
    (g) * * *
    (1) The statistical method used to evaluate groundwater monitoring 
data shall be appropriate for the distribution of constituents. Normal 
distributions of data values shall use parametric methods. Non-normal 
distributions shall use non-parametric methods. If the distribution of 
the constituents is shown by the owner or operator of the CCR unit or 
the CCR management unit to be inappropriate for a normal theory test, 
then the data must be transformed or a distribution-free (non-
parametric) theory test must be used. If the distributions for the 
constituents differ, more than one statistical method may be needed.
* * * * *
    (h) The owner or operator of the CCR unit or the CCR management 
unit must determine whether or not there is a statistically significant 
increase over background values for each constituent required in the 
particular groundwater monitoring program that applies to the CCR unit 
or the CCR management unit, as determined under Sec.  257.94(a) or 
Sec.  257.95(a).
* * * * *
    (j) The owner or operator of the CCR unit or the CCR management 
unit must comply with the recordkeeping requirements specified in Sec.  
257.105(h), the notification requirements specified in Sec.  
257.106(h), and the internet requirements specified in Sec.  
257.107(h).
0
13. Amend Sec.  257.94 by revising paragraphs (a), (b) and (f) to read 
as follows:

Sec.  257.94  Detection monitoring program.

    (a) The owner or operator of a CCR unit or a CCR management unit 
must conduct detection monitoring at all groundwater monitoring wells 
consistent with this section. At a minimum, a detection monitoring 
program must include groundwater monitoring for all constituents listed 
in appendix III to this part.
    (b) Except as provided in paragraph (d) of this section, the 
monitoring frequency for the constituents listed in appendix III to 
this part shall be at least semiannual during the active life of the 
CCR unit or the CCR management unit and the post-closure period. For 
existing CCR landfills and existing CCR surface impoundments, a minimum 
of eight

[[Page 32038]]

independent samples from each background and downgradient well must be 
collected and analyzed for the constituents listed in appendix III and 
IV to this part no later than October 17, 2017. For new CCR landfills, 
new CCR surface impoundments, and all lateral expansions of CCR units, 
a minimum of eight independent samples for each background well must be 
collected and analyzed for the constituents listed in appendices III 
and IV to this part during the first six months of sampling. For CCR 
management units, a minimum of eight independent samples from each 
background and downgradient well must be collected and analyzed for the 
constituents listed in appendix III and IV to this part no later than 
24 months after effective date of the final rule.
* * * * *
    (f) The owner or operator of the CCR unit or the CCR management 
unit must comply with the recordkeeping requirements specified in Sec.  
257.105(h), the notification requirements specified in Sec.  
257.106(h), and the internet requirements specified in Sec.  
257.107(h).
0
14. Amend Sec.  257.95 by revising paragraphs (b), (e), (g) 
introductory text, (g)(1) introductory text, the first sentence of 
(g)(3)(ii), paragraphs (g)(4), (h) introductory text, and (i) to read 
as follows:

Sec.  257.95  Assessment monitoring program.

* * * * *
    (b)(1) Within 90 days of triggering an assessment monitoring 
program, and annually thereafter:
    (i) The owner or operator of the CCR unit must sample and analyze 
the groundwater for all constituents listed in appendix IV to this 
part.
    (ii) The owner or operator of a CCR management unit must sample and 
analyze the groundwater for all constituents listed in appendix IV to 
this part no later than 24 months after effective date of the final 
rule.
    (2) The number of samples collected and analyzed for each well 
during each sampling event must be consistent with Sec.  257.93(e) and 
must account for any unique characteristics of the site, but must be at 
least one sample from each well.
* * * * *
    (e) If the concentrations of all constituents listed in appendices 
III and IV to this part are shown to be at or below background values, 
using the statistical procedures in Sec.  257.93(g), for two 
consecutive sampling events, the owner or operator may return to 
detection monitoring of the CCR unit or the CCR management unit. The 
owner or operator must prepare a notification stating that detection 
monitoring is resuming for the CCR unit or the CCR management unit. The 
owner or operator has completed the notification when the notification 
is placed in the facility's operating record as required by Sec.  
257.105(h)(7).
* * * * *
    (g) If one or more constituents in appendix IV to this part are 
detected at statistically significant levels above the groundwater 
protection standard established under paragraph (h) of this section in 
any sampling event, the owner or operator must prepare a notification 
identifying the constituents in appendix IV to this part that have 
exceeded the groundwater protection standard. The owner or operator has 
completed the notification when the notification is placed in the 
facility's operating record as required by Sec.  257.105(h)(8). The 
owner or operator of the CCR unit or the CCR management unit also must:
    (1) Characterize the nature and extent of the release and any 
relevant site conditions that may affect the remedy ultimately 
selected. The characterization must be sufficient to support a complete 
and accurate assessment of the corrective measures necessary to 
effectively clean up all releases from the CCR unit or the CCR 
management unit pursuant to Sec.  257.96. Characterization of the 
release includes the following minimum measures:
* * * * *
    (3) * * *
    (ii) Demonstrate that a source other than the CCR unit or the CCR 
management unit caused the contamination, or that the statistically 
significant increase resulted from error in sampling, analysis, 
statistical evaluation, or natural variation in groundwater quality. * 
* *
    (4) If a successful demonstration has not been made at the end of 
the 90 day period provided by paragraph (g)(3)(ii) of this section, the 
owner or operator of the CCR unit or the CCR management unit must 
initiate the assessment of corrective measures requirements under Sec.  
257.96.
* * * * *
    (h) The owner or operator of the CCR unit or the CCR management 
unit must establish a groundwater protection standard for each 
constituent in appendix IV to this part detected in the groundwater. 
The groundwater protection standard shall be:
* * * * *
    (i) The owner or operator of the CCR unit or the CCR management 
unit must comply with the recordkeeping requirements specified in Sec.  
257.105(h), the notification requirements specified in Sec.  
257.106(h), and the internet requirements specified in Sec.  
257.107(h).
0
15. Amend Sec.  257.96 by revising paragraphs (a), (b), and (f) to read 
as follows:

Sec.  257.96  Assessment of corrective measures.

    (a) Within 90 days of finding that any constituent listed in 
Appendix IV to this part has been detected at a statistically 
significant level exceeding the groundwater protection standard defined 
under Sec.  257.95(h), or immediately upon detection of a release from 
a CCR unit or a CCR management unit, the owner or operator must 
initiate an assessment of corrective measures to prevent further 
releases, to remediate any releases and to restore affected area to 
original conditions.
    (b) The owner or operator of the CCR unit or the CCR management 
unit must continue to monitor groundwater in accordance with the 
assessment monitoring program as specified in Sec.  257.95.
* * * * *
    (f) The owner or operator of the CCR unit or the CCR management 
unit must comply with the recordkeeping requirements specified in Sec.  
257.105(h), the notification requirements specified in Sec.  
257.106(h), and the internet requirements specified in Sec.  
257.107(h).
0
16. Amend Sec.  257.97 by revising paragraphs (c) introductory text, 
(d) introductory text, and (e) to read as follows:

Sec.  257.97  Selection of remedy.

* * * * *
    (c) In selecting a remedy that meets the standards of paragraph (b) 
of this section, the owner or operator of the CCR unit or the CCR 
management unit shall consider the following evaluation factors:
* * * * *
    (d) The owner or operator must specify as part of the selected 
remedy a schedule(s) for implementing and completing remedial 
activities. Such a schedule must require the completion of remedial 
activities within a reasonable period of time taking into consideration 
the factors set forth in paragraphs (d)(1) through (6) of this section. 
The owner or operator of the CCR unit or the CCR management unit must 
consider the following factors in determining the schedule of remedial 
activities:
* * * * *
    (e) The owner or operator of the CCR unit or the CCR management 
unit must comply with the recordkeeping requirements specified in Sec.  
257.105(h), the notification requirements specified

[[Page 32039]]

in Sec.  257.106(h), and the internet requirements specified in Sec.  
257.107(h).
0
17. Amend Sec.  257.98 by revising paragraphs (a)(3) introductory text, 
(b), (c)(1), and (f) to read as follows:

Sec.  257.98  Implementation of the corrective action program.

    (a) * * *
    (3) Take any interim measures necessary to reduce the contaminants 
leaching from the CCR unit or the CCR management unit, and/or potential 
exposures to human or ecological receptors. Interim measures must, to 
the greatest extent feasible, be consistent with the objectives of and 
contribute to the performance of any remedy that may be required 
pursuant to Sec.  257.97. The following factors must be considered by 
an owner or operator in determining whether interim measures are 
necessary:
* * * * *
    (b) If an owner or operator of the CCR unit or the CCR management 
unit, determines, at any time, that compliance with the requirements of 
Sec.  257.97(b) is not being achieved through the remedy selected, the 
owner or operator must implement other methods or techniques that could 
feasibly achieve compliance with the requirements.
    (c) * * *
    (1) The owner or operator of the CCR unit or the CCR management 
unit demonstrates compliance with the groundwater protection standards 
established under Sec.  257.95(h) has been achieved at all points 
within the plume of contamination that lie beyond the groundwater 
monitoring well system established under Sec.  257.91.
* * * * *
    (f) The owner or operator of the CCR unit or the CCR management 
unit must comply with the recordkeeping requirements specified in Sec.  
257.105(h), the notification requirements specified in Sec.  
257.106(h), and the internet requirements specified in Sec.  
257.107(h).
0
18. Amend Sec.  257.100 by revising the section heading and paragraph 
(a), and adding paragraph (f) to read as follows:

Sec.  257.100  Inactive CCR surface impoundments and Legacy CCR surface 
impoundments.

    (a) Inactive CCR surface impoundments and legacy CCR surface 
impoundments are subject to all of the requirements of this subpart 
applicable to existing CCR surface impoundments.
* * * * *
    (f) Timeframes for legacy CCR surface impoundments--(1) Legacy CCR 
surface impoundment applicability documentation. (i) Excepted as 
provided in paragraph (f)(1)(ii) of this section, owners and operators 
of legacy CCR surface impoundments must prepare documentation for each 
legacy CCR surface impoundment subject to the requirements of this 
subpart no later than the date the final rule is effective. At a 
minimum, the documentation for each legacy CCR surface impoundment must 
contain:
    (A) Information to identify the legacy CCR surface impoundment and 
delineate the unit boundaries, including a figure of the facility and 
where the unit is located at the facility.
    (B) The name associated with the legacy CCR surface impoundment.
    (C) The identification number of the legacy CCR surface impoundment 
if one has been assigned by the state.
    (D) Size of the legacy CCR surface impoundment (in acres).
    (E) A description of the current site conditions, including the 
current use of the inactive facility.
    (F) The proximity (in feet, or miles, if appropriate) of the legacy 
CCR surface impoundment to the closest surface water body.
    (G) The name and address of the person(s) owning and operating the 
legacy CCR surface impoundment with their phone number and email 
address.
    (H) The owner or operator of the legacy CCR surface impoundment 
must notify the Agency of the establishment of the facility's CCR 
website and the applicability of the rule, using the procedures in 
Sec.  257.107(a) via the ``contact us'' form on EPA's CCR website.
    (ii) For owners and operators of legacy CCR surface impoundments 
that completed closure of the CCR unit by removal of waste prior to the 
effective date of the final rule, no later than the effective date of 
the final rule, complete a closure certification documenting that all 
closure requirements in Sec.  257.102(c) have been met.
    (2) Design criteria. The owner or operator of a legacy CCR surface 
impoundment must:
    (i) Except for legacy CCR surface impoundments that are incised, no 
later than the date the final rule is effective, place on or 
immediately adjacent to the CCR unit the permanent identification 
marker as set forth by Sec.  257.73(a)(1).
    (ii) Except for legacy CCR surface impoundments that do not exceed 
the height and/or storage volume thresholds under Sec.  257.73(b), no 
later than three months after the date the final rule is effective, 
compile a history of construction as set forth by Sec.  257.73(c).
    (iii) Except for legacy CCR surface impoundments that are incised, 
no later than three months after the date the final rule is effective, 
complete the initial hazard potential classification assessment as set 
forth by Sec.  257.73(a)(2) and (f).
    (iv) Except for legacy CCR surface impoundments that do not exceed 
the height and/or storage volume thresholds under Sec.  257.73(b), no 
later than three months after the date the final rule is effective, 
complete the structural stability and safety factor assessments as set 
forth by Sec.  257.73(d), (e), and (f).
    (v) Except for legacy CCR surface impoundments that are incised, no 
later than nine months after the date the final rule is effective, 
prepare and maintain an Emergency Action Plan as set forth by Sec.  
257.73(a)(3).
    (3) Operating criteria. The owner or operator of the legacy CCR 
surface impoundment must:
    (i) No later than the date the final rule is effective, prepare the 
initial CCR fugitive dust control plan as set forth in Sec.  257.80(b).
    (ii) No later than the date the final rule is effective, initiate 
the inspections by a qualified person as set forth by Sec.  257.83(a).
    (iii) No later than the date the final rule is effective, prevent 
the unknowing entry, and minimize the possibility for the unauthorized 
entry, of persons or livestock onto the legacy CCR surface impoundment.
    (iv) No later than three months after the date the final rule is 
effective, complete the initial annual inspection by a qualified 
professional engineer as set forth by Sec.  257.83(b).
    (v) No later than nine months after the date the final rule is 
effective, prepare the initial inflow design flood control system plan 
as set forth in Sec.  257.82(c).
    (vi) No later than 12 months after the date the final rule is 
effective, prepare the initial annual fugitive dust control report as 
set forth in Sec.  257.80(c).
    (4) Groundwater monitoring and corrective action. The owner or 
operator of the legacy CCR surface impoundment must:
    (i) No later than six months after the date the final rule is 
effective, install the groundwater monitoring system as required by 
Sec.  257.91.
    (ii) No later than six months after the date the final rule is 
effective, develop the groundwater sampling and analysis program, 
including the selection of the statistical procedures, that will be 
used for evaluating groundwater monitoring data as required by Sec.  
257.93.
    (iii) No later than 24 months after the date the final rule is 
effective, be in compliance with the following groundwater monitoring 
requirements:
    (A) Initiate the detection monitoring program to include obtaining 
a minimum of eight independent samples

[[Page 32040]]

for each background and downgradient well, as required by Sec.  
257.94(b).
    (B) Begin evaluating the groundwater monitoring data for 
statistically significant increases over background levels for the 
constituents listed in appendix III of this part, as required by Sec.  
257.94.
    (C) Begin evaluating the groundwater monitoring data for 
statistically significant levels over groundwater protection standards 
for the constituents listed in appendix IV of this part as required by 
Sec.  257.95.
    (iv) No later than January 31 of the year after the groundwater 
monitoring system is established, prepare the initial groundwater 
monitoring and corrective action report as set forth in Sec.  
257.90(e).
    (5) Closure and post-closure care. The owner or operator of the 
legacy CCR surface impoundment must:
    (i) No later than 12 months after the date the final rule is 
effective, prepare an initial written closure plan as set forth in 
Sec.  257.102(b); and
    (ii) No later than 12 months after the date the final rule is 
effective, prepare an initial written post-closure care plan as set 
forth in Sec.  257.104(d).
0
19. Amend Sec.  257.101 by adding paragraphs (e) and (f) to read as 
follows:

Sec.  257.101  Closure or retrofit of CCR units and CCR management 
units.

* * * * *
    (e) The owner or operator of a legacy CCR surface impoundment is 
subject to the requirements of paragraphs (e)(1) and (2) of this 
section.
    (1) No later than 12 months after the date the final rule is 
effective, an owner or operator of a legacy CCR surface impoundment 
must initiate the closure of the legacy CCR surface impoundment in 
accordance with the requirements of Sec.  257.102.
    (2) An owner or operator of a legacy CCR surface impoundment that 
closes in accordance with paragraph (e)(1) of this section must include 
a statement in the notification required under Sec.  257.102(g) that 
the legacy CCR surface impoundment is closing under the requirement of 
paragraph (e)(1) of this section.
    (f) The owner or operator of a CCR management unit is subject to 
the requirements of paragraphs (f)(1) and (2) of this section.
    (1) No later than 12 months after the date the final rule is 
effective, an owner or operator of a CCR management unit must initiate 
the closure of the CCR management unit in accordance with the 
requirements of Sec.  257.102.
    (2) An owner or operator of a CCR management unit that closes in 
accordance with paragraph (f)(1) of this section must include a 
statement in the notification required under Sec.  257.102(g) that the 
CCR management unit is closing under the requirements of paragraph 
(f)(1) of this section.
0
20. Amend Sec.  257.102 by:
0
a. Revising paragraphs (a), (b)(1), and (b)(2)(iii);
0
b. Adding paragraph (b)(2)(iv);
0
c. Revising paragraphs (b)(3)(ii)(A), (b)(3)(iii), (b)(4), (c), (d)(1) 
introductory text, (d)(1)(iv), (d)(2) introductory text, (d)(3) 
introductory text, (d)(3)(i)(B), (d)(3)(iii), (e) introductory text, 
and (f)(1) introductory text;
0
d. Adding paragraph (f)(1)(iii); and
0
e. Revising paragraphs (f)(2)(i) introductory text, (f)(2)(i)(B), and 
(C);
0
f. Adding paragraphs (f)(2)(ii)(D) and (E); and
0
g. Revising paragraphs (f)(2)(iii), (f)(3), (g), (h), (i)(1), 
(i)(2)(i), (i)(4), and (j).
    The revisions and additions read as follows:

Sec.  257.102  Criteria for conducting the closure or retrofit of CCR 
units and closure of CCR management units.

    (a) Closure of a CCR landfill, CCR surface impoundment, any lateral 
expansion of a CCR unit, or a CCR management unit must be completed 
either by leaving the CCR in place and installing a final cover system 
or through removal of the CCR and decontamination of the CCR unit or 
CCR management unit, as described in paragraphs (b) through (j) of this 
section. Retrofit of a CCR surface impoundment must be completed in 
accordance with the requirements in paragraph (k) of this section.
    (b) * * *
    (1) Content of the plan. The owner or operator of a CCR unit or a 
CCR management unit must prepare a written closure plan that describes 
the steps necessary to close the CCR unit or the CCR management unit at 
any point during the active life of the CCR unit or CCR management unit 
consistent with recognized and generally accepted good engineering 
practices. The written closure plan must include, at a minimum, the 
information specified in paragraphs (b)(1)(i) through (vi) of this 
section.
    (i) A narrative description of how the CCR unit or CCR management 
unit will be closed in accordance with this section.
    (ii) If closure of the CCR unit or CCR management unit will be 
accomplished through removal of CCR from the CCR unit or CCR management 
unit, a description of the procedures to remove the CCR and 
decontaminate the CCR unit or CCR management unit in accordance with 
paragraph (c) of this section.
    (iii) If closure of the CCR unit or CCR management unit will be 
accomplished by leaving CCR in place, a description of the final cover 
system, designed in accordance with paragraph (d) of this section, and 
the methods and procedures to be used to install the final cover. The 
closure plan must also discuss how the final cover system will achieve 
the performance standards specified in paragraph (d) of this section.
    (iv) An estimate of the maximum inventory of CCR ever on-site over 
the active life of the CCR unit or CCR management unit.
    (v) An estimate of the largest area of the CCR unit or CCR 
management unit ever requiring a final cover as required by paragraph 
(d) of this section at any time during the CCR unit's active life.
    (vi) A schedule for completing all activities necessary to satisfy 
the closure criteria in this section, including an estimate of the year 
in which all closure activities for the CCR unit or CCR management unit 
will be completed. The schedule should provide sufficient information 
to describe the sequential steps that will be taken to close the CCR 
unit or CCR management unit, including identification of major 
milestones such as coordinating with and obtaining necessary approvals 
and permits from other agencies, the dewatering and stabilization 
phases of CCR surface impoundment or CCR management unit closure, or 
installation of the final cover system, and the estimated timeframes to 
complete each step or phase of CCR unit or CCR management unit closure. 
When preparing the written closure plan, if the owner or operator of a 
CCR unit or CCR management unit estimates that the time required to 
complete closure will exceed the timeframes specified in paragraph 
(f)(1) of this section, the written closure plan must include the site-
specific information, factors and considerations that would support any 
time extension sought under paragraph (f)(2) of this section.
    (2) * * *
    (iii) CCR management units. No later than 12 months after effective 
date of the final rule, the owner or operator of the CCR management 
unit must prepare an initial written closure plan consistent with the 
requirements specified in paragraph (b)(1) of this section.
    (iv) The owner or operator has completed the written closure plan 
when the plan, including the certification required by paragraph (b)(4) 
of this section, has been placed in the facility's operating record as 
required by Sec.  257.105(i)(4).
    (3) * * *
    (ii) * * *

[[Page 32041]]

    (A) There is a change in the operation of the CCR unit or CCR 
management unit that would substantially affect the written closure 
plan in effect; or
* * * * *
    (iii) The owner or operator must amend the closure plan at least 60 
days prior to a planned change in the operation of the facility, CCR 
unit, or CCR management unit or no later than 60 days after an 
unanticipated event requires the need to revise an existing written 
closure plan. If a written closure plan is revised after closure 
activities have commenced for a CCR unit or a CCR management unit, the 
owner or operator must amend the current closure plan no later than 30 
days following the triggering event.
    (4) The owner or operator of the CCR unit or the CCR management 
unit must obtain a written certification from a qualified professional 
engineer or approval from the Participating State Director or approval 
from EPA where EPA is the permitting authority that the initial and any 
amendment of the written closure plan meets the requirements of this 
section.
    (c) Closure by removal of CCR. An owner or operator may elect to 
close a CCR unit or a CCR management unit by removing and 
decontaminating all areas affected by releases from the CCR unit or the 
CCR management unit. CCR removal and decontamination of the CCR unit or 
CCR management unit are complete when constituent concentrations 
throughout the CCR unit or the CCR management unit and any areas 
affected by releases from the CCR unit or CCR management unit have been 
removed and groundwater monitoring concentrations do not exceed the 
groundwater protection standard established pursuant to Sec.  257.95(h) 
for constituents listed in appendix IV to this part.
    (d) * * *
    (1) General performance standard. The owner or operator of a CCR 
unit or CCR management unit must ensure that, at a minimum, the CCR 
unit or CCR management unit is closed in a manner that will:
* * * * *
    (iv) Minimize the need for further maintenance of the CCR unit or 
the CCR management unit; and
* * * * *
    (2) Drainage and stabilization of CCR units and CCR management 
units. The owner or operator of any CCR unit or CCR management unit 
must meet the requirements of paragraphs (d)(2)(i) and (ii) of this 
section prior to installing the final cover system required under 
paragraph (d)(3) of this section.
* * * * *
    (3) Final cover system. If a CCR unit or CCR management unit is 
closed by leaving CCR in place, the owner or operator must install a 
final cover system that is designed to minimize infiltration and 
erosion, and at a minimum, meets the requirements of paragraph 
(d)(3)(i) of this section, or the requirements of the alternative final 
cover system specified in paragraph (d)(3)(ii) of this section.
    (i) * * *
    (B) The infiltration of liquids through the closed CCR unit or CCR 
management unit must be minimized by the use of an infiltration layer 
that contains a minimum of 18 inches of earthen material.
* * * * *
    (iii) The owner or operator of the CCR unit or the CCR management 
unit must obtain a written certification from a qualified professional 
engineer or approval from the Participating State Director or approval 
from EPA where EPA is the permitting authority that the design of the 
final cover system meets the requirements of this section.
    (e) Initiation of closure activities. Except as provided for in 
paragraph (e)(4) of this section and Sec.  257.103, the owner or 
operator of a CCR unit must commence closure of the CCR unit no later 
than the applicable timeframes specified in either paragraph (e)(1) or 
(2) of this section. CCR management units are subject to the 
requirements of paragraph (e)(3) of this section.
* * * * *
    (f) * * *
    (1) Except as provided for in paragraph (f)(2) of this section, the 
owner or operator must complete closure of the CCR unit or the CCR 
management unit:
* * * * *
    (iii) For CCR management units, within five years of commencing 
closure activities.
    (2) * * *
    (i) Extensions of closure timeframes. The timeframes for completing 
closure of a CCR unit or a CCR management unit specified under 
paragraphs (f)(1) of this section may be extended if the owner or 
operator can demonstrate that it was not feasible to complete closure 
of the CCR unit or the CCR management unit within the required 
timeframes due to factors beyond the facility's control. If the owner 
or operator is seeking a time extension beyond the time specified in 
the written closure plan as required by paragraph (b)(1) of this 
section, the demonstration must include a narrative discussion 
providing the basis for additional time beyond that specified in the 
closure plan. The owner or operator must place each completed 
demonstration, if more than one time extension is sought, in the 
facility's operating record as required by Sec.  257.105(i)(6) prior to 
the end of any two-year period. Factors that may support such a 
demonstration include:
* * * * *
    (B) Time required to dewater a surface impoundment or a CCR 
management unit due to the volume of CCR contained in the CCR unit or 
the characteristics of the CCR in the unit;
    (C) The geology and terrain surrounding the CCR unit or the CCR 
management unit will affect the amount of material needed to close the 
CCR unit or the CCR management unit; or
* * * * *
    (ii) * * *
    (D) CCR management units of 40 acres or smaller may extend the time 
to complete closure by no longer than two years.
    (E) CCR management units larger than 40 acres may extend the 
timeframe to complete closure of the CCR management unit multiple 
times, in two-year increments. For each two-year extension sought, the 
owner or operator must substantiate the factual circumstances 
demonstrating the need for the extension. No more than a total of five 
two-year extensions may be obtained for any CCR management unit.
    (iii) In order to obtain additional time extension(s) to complete 
closure of a CCR unit or a CCR management unit beyond the times 
provided by paragraph (f)(1) of this section, the owner or operator of 
the CCR unit or the CCR management unit must include with the 
demonstration required by paragraph (f)(2)(i) of this section the 
following statement signed by the owner or operator or an authorized 
representative:

    I certify under penalty of law that I have personally examined 
and am familiar with the information submitted in this demonstration 
and all attached documents, and that, based on my inquiry of those 
individuals immediately responsible for obtaining the information, I 
believe that the submitted information is true, accurate, and 
complete. I am aware that there are significant penalties for 
submitting false information, including the possibility of fine and 
imprisonment.

    (3) Upon completion, the owner or operator of the CCR unit or the 
CCR management unit must obtain a certification from a qualified 
professional engineer or approval from the Participating State Director 
or approval from EPA where EPA is the

[[Page 32042]]

permitting authority verifying that closure has been completed in 
accordance with the closure plan specified in paragraph (b) of this 
section and the requirements of this section.
    (g) No later than the date the owner or operator initiates closure 
of a CCR unit or CCR management unit, the owner or operator must 
prepare a notification of intent to close a CCR unit or CCR management 
unit. The notification must include the certification by a qualified 
professional engineer or the approval from the Participating State 
Director or the approval from EPA where EPA is the permitting authority 
for the design of the final cover system as required by Sec.  
257.102(d)(3)(iii), if applicable. The owner or operator has completed 
the notification when it has been placed in the facility's operating 
record as required by Sec.  257.105(i)(7).
    (h) Within 30 days of completion of closure of the CCR unit or CCR 
management unit, the owner or operator must prepare a notification of 
closure of a CCR unit or CCR management unit. The notification must 
include the certification by a qualified professional engineer or the 
approval from the Participating State Director or the approval from EPA 
where EPA is the permitting authority as required by Sec.  
257.102(f)(3). The owner or operator has completed the notification 
when it has been placed in the facility's operating record as required 
by Sec.  257.105(i)(8).
    (i) * * *
    (1) Except as provided by paragraph (i)(4) of this section, 
following closure of a CCR unit or CCR management unit, the owner or 
operator must record a notation on the deed to the property, or some 
other instrument that is normally examined during title search.
    (2) * * *
    (i) The land has been used as a CCR unit or CCR management unit; 
and
* * * * *
    (4) An owner or operator that closes a CCR unit or CCR management 
unit in accordance with paragraph (c) of this section is not subject to 
the requirements of paragraphs (i)(1) through (3) of this section.
    (j) The owner or operator of the CCR unit or CCR management unit 
must comply with the closure recordkeeping requirements specified in 
Sec.  257.105(i), the closure notification requirements specified in 
Sec.  257.106(i), and the closure internet requirements specified in 
Sec.  257.107(i).
* * * * *
0
21. Amend Sec.  257.104 by revising paragraphs (a), (b) introductory 
text, (b)(2), (c), (d)(1), (2), (d)(3)(ii)(A), (d)(3)(iii), (d)(4), 
(e), and (f) to read as follows:

Sec.  257.104  Post-closure care requirements.

    (a) Applicability. (1) Except as provided by paragraph (a)(2) of 
this section, Sec.  257.104 applies to the owners or operators of CCR 
landfills, CCR surface impoundments, all lateral expansions of CCR 
units, and CCR management units that are subject to the closure 
criteria under Sec.  257.102.
    (2) An owner or operator of a CCR unit or a CCR management unit 
that elects to close a CCR unit or a CCR management unit by removing 
CCR as provided by Sec.  257.102(c) is not subject to the post-closure 
care criteria under this section.
    (b) Post-closure care maintenance requirements. Following closure 
of the CCR unit or the CCR management unit, the owner or operator must 
conduct post-closure care for the CCR unit or the CCR management unit, 
which must consist of at least the following:
* * * * *
    (2) If the CCR unit or the CCR management unit is subject to the 
design criteria under Sec.  257.70, maintaining the integrity and 
effectiveness of the leachate collection and removal system and 
operating the leachate collection and removal system in accordance with 
the requirements of Sec.  257.70; and
* * * * *
    (c) Post-closure care period. (1) Except as provided by paragraph 
(c)(2) of this section, the owner or operator of the CCR unit or the 
CCR management unit must conduct post-closure care for 30 years.
    (2) If at the end of the post-closure care period the owner or 
operator of the CCR unit or the CCR management unit is operating under 
assessment monitoring in accordance with Sec.  257.95, the owner or 
operator must continue to conduct post-closure care until the owner or 
operator returns to detection monitoring in accordance with Sec.  
257.95.
    (d) * * *
    (1) Content of the plan. The owner or operator of a CCR unit or a 
CCR management unit must prepare a written post-closure plan that 
includes, at a minimum, the information specified in paragraphs 
(d)(1)(i) through (iii) of this section.
    (i) A description of the monitoring and maintenance activities 
required in paragraph (b) of this section for the CCR unit or the CCR 
management unit, and the frequency at which these activities will be 
performed;
    (ii) The name, address, telephone number, and email address of the 
person or office to contact about the facility during the post-closure 
care period; and
    (iii) A description of the planned uses of the property during the 
post-closure period. Post-closure use of the property shall not disturb 
the integrity of the final cover, liner(s), or any other component of 
the containment system, or the function of the monitoring systems 
unless necessary to comply with the requirements in this subpart. Any 
other disturbance is allowed if the owner or operator of the CCR unit 
or the CCR management unit demonstrates that disturbance of the final 
cover, liner, or other component of the containment system, including 
any removal of CCR, will not increase the potential threat to human 
health or the environment. The demonstration must be certified by a 
qualified professional engineer or approved by the Participating State 
Director or approved from EPA where EPA is the permitting authority, 
and notification shall be provided to the State Director that the 
demonstration has been placed in the operating record and on the owners 
or operator's publicly accessible internet site.
    (2) Deadline to prepare the initial written post-closure plan--(i) 
Existing CCR landfills and existing CCR surface impoundments. No later 
than October 17, 2016, the owner or operator of the CCR unit must 
prepare an initial written post-closure plan consistent with the 
requirements specified in paragraph (d)(1) of this section.
    (ii) New CCR landfills, new CCR surface impoundments, and any 
lateral expansion of a CCR unit. No later than the date of the initial 
receipt of CCR in the CCR unit, the owner or operator must prepare an 
initial written post-closure plan consistent with the requirements 
specified in paragraph (d)(1) of this section.
    (iii) CCR Management Units. No later than 12 months after effective 
date of the final rule, the owner or operator of a CCR management unit 
must prepare an initial written post-closure care plan as set forth in 
paragraph (d)(1) of this section.
    (iv) The owner or operator has completed the written post-closure 
plan when the plan, including the certification required by paragraph 
(d)(4) of this section, has been placed in the facility's operating 
record as required by Sec.  257.105(i)(4).
    (3) * * *
    (ii) * * *
    (A) There is a change in the operation of the CCR unit or the CCR 
management unit that would substantially affect the written post-
closure plan in effect; or
* * * * *

[[Page 32043]]

    (iii) The owner or operator must amend the written post-closure 
plan at least 60 days prior to a planned change in the operation of the 
facility or CCR unit, or CCR management unit, or no later than 60 days 
after an unanticipated event requires the need to revise an existing 
written post-closure plan. If a written post-closure plan is revised 
after post-closure activities have commenced for a CCR unit or a CCR 
management unit, the owner or operator must amend the written post-
closure plan no later than 30 days following the triggering event.
    (4) The owner or operator of the CCR unit or the CCR management 
unit must obtain a written certification from a qualified professional 
engineer or an approval from the Participating State Director or an 
approval from EPA where EPA is the permitting authority that the 
initial and any amendment of the written post-closure plan meets the 
requirements of this section.
    (e) Notification of completion of post-closure care period. No 
later than 60 days following the completion of the post-closure care 
period, the owner or operator of the CCR unit or the CCR management 
unit must prepare a notification verifying that post-closure care has 
been completed. The notification must include the certification by a 
qualified professional engineer or the approval from the Participating 
State Director or the approval from EPA where EPA is the permitting 
authority verifying that post-closure care has been completed in 
accordance with the closure plan specified in paragraph (d) of this 
section and the requirements of this section. The owner or operator has 
completed the notification when it has been placed in the facility's 
operating record as required by Sec.  257.105(i)(13).
    (f) The owner or operator of the CCR unit or the CCR management 
unit must comply with the recordkeeping requirements specified in Sec.  
257.105(i), the notification requirements specified in Sec.  
257.106(i), and the internet requirements specified in Sec.  
257.107(i).
0
22. Amend Sec.  257.105 by:
0
a. Revising paragraphs (a), (b), (c), (d) and (f) introductory text;
0
b. Adding paragraph (f)(25);
0
c. Revising paragraphs (g) introductory text, (h) introductory text, 
(i) introductory text, (i)(7), and (8): and
0
d. Adding paragraph (k).
    The revisions and additions read as follows:

Sec.  257.105  Recordkeeping requirements.

    (a) Operating Record. Each owner or operator of a CCR unit or CCR 
management unit subject to the requirements of this subpart must 
maintain files of all information required by this section in a written 
operating record at their facility.
    (b) Document Retention. Unless specified otherwise, each file must 
be retained for at least five years following the date of each 
occurrence, measurement, maintenance, corrective action, report, 
record, or study.
    (c) Recordkeeping for multiple CCR units or CCR management units. 
An owner or operator of more than one CCR unit or CCR management unit 
subject to the provisions of this subpart may comply with the 
requirements of this section in one recordkeeping system provided the 
system identifies each file by the name of each CCR unit. The files may 
be maintained on microfilm, on a computer, on computer disks, on a 
storage system accessible by a computer, on magnetic tape disks, or on 
microfiche.
    (d) State Director and/or appropriate Tribal authority 
notification. The owner or operator of a CCR unit or CCR management 
unit must submit to the State Director and/or appropriate Tribal 
authority any demonstration or documentation required by this subpart, 
if requested, when such information is not otherwise available on the 
owner or operator's publicly accessible internet site.
* * * * *
    (f) Design criteria. The owner or operator of a CCR unit or CCR 
management unit subject to this subpart must place the following 
information, as it becomes available, in the facility's operating 
record:
* * * * *
    (25) The Facility Evaluation Report as required by Sec.  257.75(c).
    (g) Operating criteria. The owner or operator of a CCR unit or CCR 
management unit subject to this subpart must place the following 
information, as it becomes available, in the facility's operating 
record:
* * * * *
    (h) Groundwater monitoring and corrective action. The owner or 
operator of a CCR unit or CCR management unit subject to this subpart 
must place the following information, as it becomes available, in the 
facility's operating record:
* * * * *
    (i) Closure and post-closure care. The owner or operator of a CCR 
unit or CCR management unit subject to this subpart must place the 
following information, as it becomes available, in the facility's 
operating record:
* * * * *
    (7) The notification of intent to close a CCR unit or CCR 
management unit as required by Sec.  257.102(g).
    (8) The notification of completion of closure of a CCR unit or CCR 
management unit as required by Sec.  257.102(h).
* * * * *
    (k) Legacy CCR surface impoundments. In addition to the information 
specified in paragraphs (e) through (j) of this section, the owner or 
operator of a legacy CCR surface impoundment subject to this subpart 
must place the following information, as it becomes available, in the 
facility's operating record:
    (1) The applicability documentation required by Sec.  
257.100(f)(1)(i).
    (2) The completion of closure by removal certification as specified 
under Sec.  257.100(f)(1)(ii).
0
23. Amend Sec.  257.106 by:
0
a. Revising paragraphs (a), (b), (c), (d), and (f) introductory text;
0
b. Adding paragraph (f)(24);
0
c. Revising paragraphs (g) introductory text, (h) introductory text, 
(h)(5), (i) introductory text, (i)(7), and (8); and
0
d. Adding paragraph (k).
    The revisions and additions read as follows:

Sec.  257.106  Notification requirements.

    (a) Deadline to submit notification to the relevant State Director 
and/or appropriate Tribal authority. The notifications required under 
paragraphs (e) through (i) of this section must be sent to the relevant 
State Director and/or appropriate Tribal authority before the close of 
business on the day the notification is required to be completed. For 
purposes of this section, before the close of business means the 
notification must be postmarked or sent by electronic mail (email). If 
a notification deadline falls on a weekend or federal holiday, the 
notification deadline is automatically extended to the next business 
day.
    (b) Notifications to Tribal authority. If any CCR unit or CCR 
management unit is located in its entirety within Indian Country, the 
notifications of this section must be sent to the appropriate Tribal 
authority. If any CCR unit or CCR management unit is located in part 
within Indian Country, the notifications of this section must be sent 
both to the appropriate State Director and Tribal authority.
    (c) Combining notifications. Notifications may be combined as long 
as the deadline requirement for each notification is met.
    (d) Notification deadline after placement in operating record. 
Unless

[[Page 32044]]

otherwise required in this section, the notifications specified in this 
section must be sent to the State Director and/or appropriate Tribal 
authority within 30 days of placing in the operating record the 
information required by Sec.  257.105.
* * * * *
    (f) Design criteria. The owner or operator of a CCR unit or CCR 
management unit subject to this subpart must notify the State Director 
and/or appropriate Tribal authority when information has been placed in 
the operating record and on the owner or operator's publicly accessible 
internet site. The owner or operator must:
* * * * *
    (24) Provide notification of the availability of the Facility 
Evaluation Report as specified by Sec.  257.105(f)(25).
    (g) Operating criteria. The owner or operator of a CCR unit or CCR 
management unit subject to this subpart must notify the State Director 
and/or appropriate Tribal authority when information has been placed in 
the operating record and on the owner or operator's publicly accessible 
internet site. The owner or operator must:
* * * * *
    (h) Groundwater monitoring and corrective action. The owner or 
operator of a CCR unit or CCR management unit subject to this subpart 
must notify the State Director and/or appropriate Tribal authority when 
information has been placed in the operating record and on the owner or 
operator's publicly accessible internet site. The owner or operator 
must:
* * * * *
    (5) Provide notification that the CCR unit or CCR management unit 
is returning to a detection monitoring program specified under Sec.  
257.105(h)(7).
* * * * *
    (i) Closure and post-closure care. The owner or operator of a CCR 
unit or CCR management unit subject to this subpart must notify the 
State Director and/or appropriate Tribal authority when information has 
been placed in the operating record and on the owner or operator's 
publicly accessible internet site. The owner or operator must:
* * * * *
    (7) Provide notification of intent to close a CCR unit or CCR 
management unit specified under Sec.  257.105(i)(7).
    (8) Provide notification of completion of closure of a CCR unit or 
CCR management unit specified under Sec.  257.105(i)(8).
* * * * *
    (k) Legacy CCR surface impoundments. In addition to the information 
specified in paragraphs (e) through (j) of this section, the owner or 
operator of a legacy CCR surface impoundment subject to this subpart 
must notify the State Director and/or appropriate Tribal authority when 
information has been placed in the operating record and on the owner or 
operator's publicly accessible internet site. The owner or operator 
must:
    (1) Provide notification of the availability of the applicability 
documentation as specified under Sec.  257.105(k)(1).
    (2) Provide notification of the availability of the completion of 
closure by removal certification as specified under Sec.  
257.105(k)(2).
0
24. Amend Sec.  257.107 by:
0
a. In paragraph (a) adding a paragraph heading and revising the first 
sentence;
0
b. Revising paragraphs (b), (c), (d), and (f) introductory text;
0
c. Adding paragraph (f)(24);
0
d. Revising paragraphs (g) introductory text, (h) introductory text and 
(h)(5);
0
e. Revising paragraphs (i) introductory text, (i)(7), and (8); and
0
f. Adding paragraph (k).
    The revisions and additions read as follows:

Sec.  257.107  Publicly accessible internet site requirements.

    (a) CCR website requirement. Each owner or operator of a CCR unit 
or CCR management unit subject to the requirements of this subpart must 
maintain a publicly accessible internet site (CCR website) containing 
the information specified in this section. * * *
    (b) CCR website for multiple units. An owner or operator of more 
than one CCR unit or CCR management unit subject to the provisions of 
this subpart may comply with the requirements of this section by using 
the same CCR website for multiple CCR units or CCR management units 
provided the CCR website clearly delineates information by the name or 
identification number of each unit.
    (c) Document retention on a CCR website. Unless otherwise required 
in this section, the information required to be posted to the CCR 
website must be made available to the public for at least five years 
following the date on which the information was first posted to the CCR 
website.
    (d) Website posting deadline after placement in operating record. 
Unless otherwise required in this section, the information must be 
posted to the CCR website within 30 days of placing the pertinent 
information required by Sec.  257.105 in the operating record.
* * * * *
    (f) Design criteria. The owner or operator of a CCR unit or CCR 
management unit subject to this subpart must place the following 
information on the owner or operator's CCR website:
* * * * *
    (24) The Facility Evaluation Report as specified under Sec.  
257.105(f)(25).
    (g) Operating criteria. The owner or operator of a CCR unit or CCR 
management unit subject to this subpart must place the following 
information on the owner or operator's CCR website:
* * * * *
    (h) Groundwater monitoring and corrective action. The owner or 
operator of a CCR unit or CCR management unit subject to this subpart 
must place the following information on the owner or operator's CCR 
website:
* * * * *
    (5) The notification that the CCR unit or CCR management unit is 
returning to a detection monitoring program specified under Sec.  
257.105(h)(7).
* * * * *
    (i) Closure and post-closure care. The owner or operator of a CCR 
unit or CCR management unit subject to this subpart must place the 
following information on the owner or operator's CCR website:
* * * * *
    (7) The notification of intent to close a CCR unit or CCR 
management unit specified under Sec.  257.105(i)(7).
    (8) The notification of completion of closure of a CCR unit or CCR 
management unit specified under Sec.  257.105(i)(8).
* * * * *
    (k) Legacy CCR surface impoundments. In addition to the information 
specified in paragraphs (e) through (j) of this section, the owner or 
operator of a legacy CCR surface impoundment subject to this subpart 
must place the following information on the owner or operator's CCR 
website:
    (1) The applicability documentation as specified under Sec.  
257.105(k)(1).
    (2) The completion of closure by removal certification as specified 
under Sec.  257.105(k)(2).

[FR Doc. 2023-10048 Filed 5-17-23; 8:45 am]
BILLING CODE 6560-50-P