[Federal Register Volume 88, Number 155 (Monday, August 14, 2023)]
[Proposed Rules]
[Pages 55220-55274]
[FR Doc No: 2023-17023]

Vol. 88

Monday,

No. 155

August 14, 2023

Part III

Environmental Protection Agency

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

40 CFR Part 257

Alabama: Denial of State Coal Combustion Residuals Permit Program;
Proposed Rule

Federal Register / Vol. 88, No. 155 / Monday, August 14, 2023 /
Proposed Rules

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

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 257

[EPA-HQ-OLEM-2022-0903; FRL 11262-01-OLEM]

Alabama: Denial of State Coal Combustion Residuals Permit Program

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of availability; request for comment.

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

SUMMARY: Pursuant to section 4005(d) of the Resource Conservation and
Recovery Act (RCRA), the Environmental Protection Agency (EPA or the
Agency) is proposing to deny the Alabama Department of Environmental
Management's (ADEM or Department) Application for approval of the
Alabama coal combustion residuals (CCR) permit program (Application).
After reviewing the State CCR permit program Application submitted by
ADEM on December 29, 2021, and additional relevant materials, and based
on extensive discussions with ADEM regarding its Application, EPA has
preliminarily determined that Alabama's CCR permit program does not
meet the standard for approval under RCRA. This document announces that
EPA is seeking comment on this proposal during a 60-day public comment
period and will be holding an in-person public hearing on EPA's
proposed denial of Alabama's CCR permit program.

DATES:
    Comments due. Comments must be received on or before October 13,
2023.
    Public Hearing: EPA will hold an in-person public hearing on
September 20, 2023, and a virtual public hearing on September 27, 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-OLEM-2022-0903, 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: Michelle Lloyd, Office of Resource
Conservation and Recovery, Materials Recovery and Waste Management
Division, U.S. 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 notice 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. Overview of Proposed Action
    B. Background
    C. Statutory Authority
III. The Alabama CCR Permit Program Application
    A. Alabama CCR Units and Resources
    B. Alabama CCR Regulations
    C. Alabama Authority To Regulate CCR
    D. Alabama Permits
    E. Summary of EPA Communications With Alabama
IV. EPA Analysis of the Alabama Application and Basis for Denial
    A. Legal Authority To Evaluate State CCR Program Submittals
    1. The Statute Requires EPA To Consider a State's CCR Permits
When Determining Whether To Approve the Program if the Information
Is Available
    2. EPA Is Not Required To Approve a Deficient State Program and
Then Redress the Deficiencies Through RCRA's Program Review
Provisions
    B. EPA's Analysis of the Alabama CCR Regulations
    1. Adequacy of Technical Criteria
    2. Review of Generally Applicable Alabama CCR Permit Program
Statutes and Regulations
    C. EPA's Analysis of Alabama's Permits Issued Under the State
CCR Regulations
    1. Colbert Fossil Plant
    2. Plant Gadsden
    3. Plant Gorgas
    4. Plant Greene County
    5. EPA conclusion About Alabama's Implementation of the CCR
Regulations
V. Proposed Action

List of Acronyms

ACM Assessment of Corrective Measures
ADEM Alabama Department of Environmental Management
ASD alternative source demonstration
BGS below ground surface
CBI Confidential Business Information
CCP coal combustion product
CCR coal combustion residuals
CD Consent Decree
CFR Code of Federal Regulations
CY cubic yards
eFile electronic filing system
EPA Environmental Protection Agency
EPRI Electric Power Research Institute
FR Federal Register
GWMCA groundwater monitoring and corrective action
GWMP Groundwater Monitoring Plan
GWPS groundwater protection standard
HSWA Hazardous and Solid Waste Amendments
ICR Information Collection Request
MCL maximum contaminant level
MNA Monitored Natural Attenuation
MSL mean sea level
NOPV Notice of Potential Violation
NPDES National Pollutant Discharge Elimination System
RCRA Resource Conservation and Recovery Act
RTC Response to Comments
SSI statistically significant increase
SSL statistically significant level
TSD Technical Support Document
TVA Tennessee Valley Authority
USGS U.S. Geological Survey
USWAG Utility Solid Waste Activities Group
WBWT waste below the water table
WIIN Water Infrastructure Improvements for the Nation

I. Public Participation

A. Written Comments

    Submit your comments, identified by Docket ID No. EPA-HQ-OLEM-OLEM-
2022-0903, 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. 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 September 18, 2023.
    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 pre-register, opportunities to
speak may be limited based upon the number of pre-registered speakers.
Therefore, EPA strongly encourages anyone wishing to speak to pre-
register. 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 description, please pre-register for the
hearing with the person listed in the FOR FURTHER INFORMATION CONTACT
section and describe your needs by September 6, 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 virtual 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 September 25, 2023.
    EPA will make every effort to follow the schedule as closely as
possible on the day of the hearing; however, please plan for the
hearing 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 EPA with a copy of
their oral testimony electronically (via email) to the 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
wishing to provide testimony and who have pre-registered. While EPA
will make every effort to accommodate all speakers who do not pre-
register, opportunities to speak may be limited based upon the number
of pre-registered speakers. Therefore, EPA strongly encourages anyone
wishing to speak to pre-register. 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
this action.
    Please note that any updates made to any aspect of the hearing will
be posted online on 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 service of a translator, please pre-register for
the hearing and describe your needs on the registration form by
September 13, 2023. If you require special accommodations such as audio
description or closed captioning, please pre-register for the hearing
and describe your needs on the registration form by September 13, 2023.
Alternatively, registrants may notify the person listed in the FOR
FURTHER INFORMATION CONTACT section of any special needs. We may not be
able to arrange accommodations without advanced notice.

II. General Information

A. Overview of Proposed Action

    On April 17, 2015, EPA published a final rule, creating 40 CFR part
257, subpart D,\1\ that established a comprehensive set of minimum
Federal requirements for the disposal of CCR in landfills and surface
impoundments (80 FR 21302) (``Federal CCR regulations''). Section 2301
of the 2016 Water Infrastructure Improvements for the Nation (WIIN) Act
amended section 4005 of RCRA, creating a new subsection (d) that
establishes a Federal CCR permit program that is similar to the permit
programs under RCRA

subtitle C and other environmental statutes. See 42 U.S.C. 6945(d).
---------------------------------------------------------------------------

    \1\ Unless otherwise specified, all references to part 257 and
part 239 in this notice are to title 40 of the Code of Federal
Regulations (CFR).
---------------------------------------------------------------------------

    RCRA section 4005(d) also allows states to seek approval for a
State CCR permit program that will operate in lieu of a Federal CCR
permit program in the State. The statute provides that within 180 days
after a State submits an application to the Administrator for approval,
EPA shall approve the State permit program if the Administrator
determines that the State program requires each CCR unit located in the
State to achieve compliance with either the Federal requirements or
other State requirements that EPA determines, after consultation with
the State, are at least as protective as those included in the Federal
CCR regulations. See, 42 U.S.C. 6945(d)(1)(B).
    On December 29, 2021, ADEM submitted its State CCR permit program
Application to EPA Region 4 requesting approval of the State's partial
CCR permit program.2 3 ADEM established State CCR
regulations that mirrored the provisions in the Federal CCR regulations
with additional State-specific provisions and clarifications. Though
ADEM primarily adopted the language in the Federal CCR regulations, EPA
reviewed both proposed and final permits Alabama issued under its CCR
program and concluded that ADEM was interpreting its State regulations
in a manner inconsistent with the plain language of the Federal
requirements, and that, as a result, the permits for CCR units in the
State contain permit terms that are neither the same as, nor as
protective as, the Federal CCR regulations. Specifically, EPA
identified deficiencies in ADEM's permits with respect to the closure
requirements for unlined surface impoundments and the associated
groundwater monitoring network and corrective action requirements. EPA
discussed these issues with ADEM, and, despite EPA's concerns, the
State declined to modify the existing permits and proceeded to issue
another CCR permit with the same deficient provisions. Further, ADEM
failed to adequately explain how the permits ensured that each CCR unit
would achieve compliance with either the Federal requirements or other
State requirements that are at least as protective as the requirements
in the Federal CCR regulations.
---------------------------------------------------------------------------

    \2\ Alabama Department of Environmental Management. Application
For CCR Permit Program Approval. December 2021.
    \3\ In the December 29, 2021 Application, Alabama sought a
partial program approval (rather than full program approval) of the
State's CCR permit program because it is not seeking approval for
some of its CCR regulations. Specifically, ADEM is not seeking
approval for six items that are listed in Unit IV.B.1.b of this
preamble and in the Technical Support Document Volume III. See
Volume III: Technical Support Document for the Proposed Notice to
Deny Alabama's Coal Combustion Residuals Permit Program, EPA
Analysis of Alabama CCR Permitting and Technical Regulations. U.S.
Environmental Protection Agency, Office of Land and Emergency
Management (5304T), 1200 Pennsylvania Avenue NW, Washington, DC
20460. August 2023.
---------------------------------------------------------------------------

    EPA is proposing to deny Alabama's request for approval of its CCR
permit program Application pursuant to RCRA section 4005(d)(1)(B),
because the State's program does not meet either standard for approval.
42 U.S.C. 6945(d)(1)(B).

B. Background

    CCR are generated from the combustion of coal, including solid
fuels classified as anthracite, bituminous coal, subbituminous coal,
and lignite, for the purpose of generating steam to power a generator
to produce electricity or electricity and other thermal energy by
electric utilities and independent power producers. CCR, commonly known
as coal ash, include fly ash, bottom ash, boiler slag, and flue gas
desulfurization materials.
    As noted above, on April 17, 2015, EPA published a final rule that
established a comprehensive set of minimum Federal requirements in 40
CFR part 257, subpart D for the disposal of CCR in landfills and
surface impoundments. The rule created a self-implementing program that
regulates the location, design, operating criteria, and groundwater
monitoring and corrective action for CCR units, as well as the closure
and post-closure care of CCR units. The rule also includes requirements
for recordkeeping and notifications for CCR units. EPA has since
amended 40 CFR part 257, subpart D (81 FR 51802, August 5, 2016), (83
FR 36435, July 30, 2018), (85 FR 53516, August 28, 2020), (85 FR 72506,
November 12, 2020). More information on these rules is provided in the
Technical Support Document (TSD) Volume III.

C. Statutory Authority

    EPA is issuing this proposed action pursuant to sections 4005(d)
and 7004(b)(1) of RCRA. See 42 U.S.C. 6945(d) and 6974(b)(1). As stated
above, section 2301 of the WIIN Act amended section 4005 of RCRA,
creating a new subsection (d) that establishes a Federal CCR permitting
program similar to permit programs under RCRA subtitle C and other
environmental statutes. See 42 U.S.C. 6945(d).
    Under RCRA section 4005(d)(1)(A), 42 U.S.C. 6945(d)(1)(A), states
seeking approval of a permit program must submit to the Administrator,
``in such form as the Administrator may establish, evidence of a permit
program or other system of prior approval and conditions under [S]tate
law for regulation by the State of coal combustion residuals units that
are located in the State.'' EPA shall approve a State permit program if
the Administrator determines that the State program requires each CCR
unit located in the State to achieve compliance with either: (1) The
Federal CCR requirements at 40 CFR part 257, subpart D; or (2) Other
State criteria that the Administrator, after consultation with the
State, determines to be ``at least as protective as'' the Federal
requirements. See 42 U.S.C. 6945(d)(1)(B). The Administrator must make
a final determination, after providing for public notice and an
opportunity for public comment, within 180 days of determining that the
State has submitted a complete application consistent with RCRA section
4005(d)(1)(A).\4\ See 42 U.S.C. 6945(d)(1)(B). EPA may approve a State
CCR permit program in whole or in part. Id. Once approved, the State
permit program operates in lieu of the Federal requirements. See 42
U.S.C. 6945(d)(1)(A). In a State with a partial permit program, only
the State requirements that have been approved operate in lieu of the
Federal requirements, and facilities remain responsible for compliance
with all remaining non-State approved requirements in 40 CFR part 257,
subpart D.
---------------------------------------------------------------------------

    \4\ See U.S. Environmental Protection Agency. Coal Combustion
Residuals State Permit Program Guidance Document; Interim Final,
August 2017, Office of Land and Emergency Management, Washington, DC
20460 (providing that the 180-day deadline does not start until EPA
determines the application is complete).
---------------------------------------------------------------------------

    As noted above, the Federal CCR regulations are self-implementing
and that means that CCR landfills and surface impoundments must comply
with the terms of the rule even prior to obtaining a Federal permit or
permit issued by an approved State, and noncompliance with any
requirement of the Federal CCR regulations can be directly enforced
against the facility. Once a final CCR permit is issued by an approved
State or pursuant to a Federal CCR permit program, however, the terms
of the permit apply in lieu of the terms of the Federal CCR regulations
and/or requirements in an approved State program, and RCRA section
4005(d)(3) provides a permit shield against direct enforcement of the
applicable Federal or State CCR regulations (meaning the permits terms

become the enforceable requirements for the permittee).
    In addition, RCRA section 7004(b) applies to all RCRA programs,
directing that ``public participation in the development, revision,
implementation, and enforcement of any. . .program under this chapter
shall be provided for, encouraged, and assisted by the Administrator
and the States.'' 42 U.S.C. 6974(b)(1).

III. The Alabama CCR Permit Program Application

    On December 29, 2021, ADEM submitted its revised CCR permit program
Application to EPA Region 4.\5\ The Application requested approval of
the State's partial CCR permit program.\6\ Alabama's first CCR
regulations were promulgated in 2018 and continued to be revised over
the next several years in response to public comment, discussions
between ADEM and EPA, and changes to the Federal CCR regulations in 40
CFR part 257, subpart D.
---------------------------------------------------------------------------

    \5\ Application to USEPA Region IV for CCCR Permit Program
Approval in Accordance with Section 4005 of the Resource
Conservation and Recovery Act (RCRA) Alabama Department of
Environmental Management Land Division-Solid Waste Branch. December
2021.
    \6\ ADEM previously submitted CCR permit program applications on
July 12, 2018, and February 26, 2021. For purposes of this proposed
action, EPA reviewed the most recent Application submitted on
December 29, 2021.
---------------------------------------------------------------------------

    EPA conducted an analysis of the Alabama CCR permit program
Application, including a thorough analysis of ADEM's statutory
authorities for the CCR program, as well as regulations at Alabama
Administrative Code Chapter. 335-13-15, Standards for the Disposal of
Coal Combustion Residuals in Landfills and Impoundments. This analysis
is discussed in Unit IV.B.2.b of this preamble and in the TSD Volume
III. EPA also reviewed Alabama's permitting regulations, as well as
recent and ongoing permit decisions ADEM was making under its CCR
regulations.

A. Alabama CCR Units and Resources

    In the Program Narrative in the Application, ADEM identified 16
units that are currently, or have been, used for disposal of CCR (3
landfills and 13 surface impoundments) in Alabama. ADEM stated that it
has the personnel and funding to administer a CCR permit program. The
State also indicated that its program is funded from three sources:
tipping fees collected for the disposal of solid waste, permitting
fees, and civil penalties from enforcement orders.

B. Alabama CCR Regulations

    ADEM Administrative Code Chapter 335-13-15 largely replicates the
requirements of 40 CFR part 257, subpart D, for the portions of those
regulations for which the State is seeking approval. In addition to the
technical criteria at ADEM Chapter 335-13-15, ADEM has adopted State-
specific permitting requirements, including public participation
requirements, at ADEM Administrative Code Chapter. 335-13-05. ADEM also
has additional reporting and approval requirements for CCR units, as
described in the TSD Volume III.

C. Alabama Authority To Regulate CCR

    ADEM derives its authority to operate the Solid Waste Program,
which includes CCR, in Alabama pursuant to the following statutory
provisions of the Code of Alabama, 1975: (1) Section 22-22A-5 provides
the Department with the authority to administer and enforce the State's
Solid Wastes and Recyclable Materials Management Act, to adopt and
promulgate rules, regulations, and standards through the Environmental
Management Commission, and to develop environmental policy for the
State; and to serve as the State Agency responsible for administering
federally-approved or federally-delegated environmental programs; (2)
Section 22-27-9 provides ADEM with authority over the management of
solid waste in the State (except for the collection and transportation
of nonhazardous and nonmedical solid waste) and the permitting and
operation of solid waste management facilities; and (3) Section 22-27-
12 provides ADEM with the authority to promulgate and adopt rules
establishing requirements for the management of solid waste and to
issue permits with conditions regarding the management of such solid
waste.

D. Alabama Permits

    Unlike Georgia, Texas, and Oklahoma (currently the only three
States with EPA approval for State CCR permit programs), Alabama had
already begun implementing its State CCR permit program and issuing
permits prior to its submittal of an Application for EPA approval of
the State's CCR permit program. At the time of submission of ADEM's
December 29, 2021 Application, ADEM had issued permits for the
following CCR facilities: (1) the James H. Miller Electric Generating
Plant (Permit #37-51; issued December 18, 2020); (2) Greene County
Electric Generating Plant (Permit #32-03: issued December 18, 2020);
(3) Gadsden Steam Plant (Permit #28-09, issued December 18, 2020); (4)
James M. Barry Electric Generating Plant (Permit #49-35, issued July 1,
2021); (5) E.C. Gaston Electric Generating Plant (Permit #59-16, issued
May 25, 2021); and (6) Charles R. Lowman Power Plant (Permit #65-06,
issued August 30, 2021). At the time of submission of the December 29,
2021 Application, permits were under development by ADEM at two other
facilities: the William C. Gorgas Electric Generating Plant and
Tennessee Valley Authority (TVA) Plant Colbert. Since the submission of
ADEM's Application, ADEM has proceeded to issue both the Plant Gorgas
Permit (Permit #64-12 issued February 28, 2022) and the TVA Colbert
Permit (Permit #17-11, issued October 25, 2022).

E. Summary of EPA Communications With Alabama

    As part of EPA's review of State CCR permit programs, the Agency
engages the State both before and after submittal of a State CCR permit
program application. These discussions serve a number of purposes; for
example, EPA engages in these discussions to help the State determine
the scope of the CCR permit program it wants to adopt (e.g., full or
partial program) and to ensure the State establishes the necessary
State CCR regulations prior to submitting the request for program
approval. EPA also assists the State in determining what to include in
the Narrative Statement component of its permit program application,
which serves as a roadmap to the State's CCR permit program. EPA also
uses these discussions to clarify questions raised during the public
comment period about the State program. To the extent the State
implements its CCR regulations prior to EPA's determination of State
program adequacy, EPA will also discuss the State's interpretation and
implementation of its program to ensure that EPA fully understands the
program and to determine which of the two statutory standards EPA will
use to evaluate the State program. EPA took the same approach with
Alabama as with other states seeking approval, and, as detailed below,
EPA and ADEM have had extensive discussions about the State's CCR
permit program.\7\
---------------------------------------------------------------------------

    \7\ EPA has attempted to identify all the interactions between
EPA and ADEM with respect to the State's CCR permit program. A
summary of the interactions between EPA and ADEM is included in the
docket to this notice in Volume II: Technical Support Document for
the Proposed Notice to Deny Alabama's Coal Combustion Residuals
Permit Program, Communication Between EPA and ADEM. U.S.
Environmental Protection Agency Office of Land and Emergency
Management (5304T). August 2023. In addition, copies of emails and
letters between EPA and ADEM can be found in the docket.

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

    EPA began telephone calls and meetings with ADEM about its
development of an Application for a CCR permit program in January 2018
and continued them through July 2022. In the early calls, EPA and ADEM
discussed the process for EPA to review and approve State CCR permit
programs, ADEM's plans for formally adopting CCR regulations, its
anticipated timeline for submitting a CCR permit program Application to
EPA, and ADEM's permit requirements. During these calls, EPA reviewed
ADEM's submission and sent comments to ADEM on those documents. The
frequency of calls between EPA and ADEM varied depending on the stage
of ADEM's efforts to develop and submit (or re-submit) its CCR permit
program Application. For example, during ADEM's public comment periods
associated with State rulemaking, or during periods of re-working
regulations or documents, calls were held less frequently. When ADEM
had questions or requested EPA input, calls were held more often.
    After ADEM's initial CCR regulations became effective in 2018, the
State began to issue permits. Calls were then held on specific
facilities and technical issues that ADEM sought EPA's input on, such
as specific corrective action proposed remedies or closure methods. In
addition, consistent with RCRA section 4005(d), EPA began discussions
with ADEM on specific facilities and permits to evaluate whether ADEM
was requiring, as part of its permit process, each CCR unit in the
State ``to achieve compliance with'' the Federal part 257 standards or
``other State criteria that the Administrator, after consultation with
the State, determines to be at least as protective as'' the Federal
criteria.
    Of particular concern to the Agency were facilities that were
closing (or had already closed) unlined CCR surface impoundments while
leaving waste (i.e., CCR) below the water table (WBWT). On March 15,
2022, EPA shared a list of such facilities in Alabama with ADEM and
scheduled discussions regarding the closures and groundwater monitoring
activities at the Greene County Electric Generating Plant and the
Gadsden Steam Plant. Discussions also focused on the William C. Gorgas
Electric Generating Plant. ADEM had issued permits at all three of
these facilities. During these discussions and written communication,
EPA expressed concern that Alabama's permit program appeared to differ
from the Federal program, and that these differences appeared to make
the State's program less protective than the Federal program. The
Agency specifically identified problems with the State's permit
requirements covering closure of unlined surface impoundments,
groundwater monitoring networks, and corrective action. See also Unit
IV.C of this preamble below and the TSD Volume I for a detailed
discussion of the deficiencies in ADEM's CCR permits. In addition to
the concerns raised with respect to Plants Greene, Gorgas, and Gadsden,
EPA has also raised concerns with respect to the TVA Plant Colbert
permit. On June 29, 2022, ADEM posted public notice of the draft permit
for Plant Colbert. Because the proposed permit for Plant Colbert raised
many of the same issues already being discussed with respect to Plants
Greene, Gorgas, and Gadsden, EPA submitted a letter to ADEM outlining
specific concerns with respect to the proposed permit.\8\
---------------------------------------------------------------------------

    \8\ Letter from Carolyn Hoskinson, Director, Office of Resource
Conservation and Recovery, to Mr. Russell A. Kelly, Chief, Permits
and Services Division, and Mr. Steve Cobb, Chief, Land Division. EPA
Comments on Proposed Permit, Tennessee Valley Authority Colbert
Fossil Plant, Alabama Department of Environmental Management, Permit
No. 17-11. September 15, 2022.
---------------------------------------------------------------------------

    As a result of these discussions, on July 7, 2022, EPA informed
ADEM via telephone that the Agency was putting on hold its completeness
review of ADEM's CCR permit program Application until Alabama
demonstrated to EPA that the State was implementing its program
consistent with the Federal CCR regulations. Further, EPA explained to
ADEM that it was exploring options for actions to take at the Federal
level with respect to both the CCR permit program Application, and at
specific facilities where there are outstanding concerns.
    On October 25, 2022, ADEM proceeded to issue a CCR permit to Plant
Colbert without revising the proposed permit to address EPA's concerns.
In a letter dated October 27, 2022, ADEM responded to EPA's letter
regarding Plant Colbert, presenting an interpretation of the
requirements applicable to closing CCR impoundments that EPA had
previously rejected in the discussions about the interpretation of the
Federal CCR regulations with ADEM described above and in EPA's Part A
proposed and final decisions. See discussion of Part A proposals in
Unit IV.C. of this preamble. To date, the State has not taken action to
revise the permits issued to Plants Colbert, Green, Gorgas, or Gadsden
to address the deficiencies EPA noted to ADEM.
    On December 9, 2022, ADEM gave EPA notice of its intent to sue EPA
under section 7002(a)(1)(A) and (1)(B) of RCRA, alleging EPA failed to
perform a nondiscretionary duty to approve the State's CCR permit
program.\9\ Among other things, ADEM asserted that EPA failed to comply
with the statutory requirement to approve the State's CCR permit
program within 180 days of the State's submittal of the permit program
Application on December 29, 2021. On February 1, 2023, EPA responded to
ADEM's Notice of Intent to Sue letter and informed the State that the
180-day timeframe does not start until EPA determines that a State's
Application is administratively complete and that, in this case, EPA
did not start the clock because EPA's concerns with ADEM's
interpretation of the minimum requirements of the Federal CCR
regulations had yet to be resolved and EPA was providing an opportunity
for ADEM to submit further Application information.\10\ EPA further
stated that the Agency could evaluate the State's program on the
current record if ADEM decided not to supplement its Application with
an explanation of how the State's interpretation of its regulations is
at least as protective as the Federal CCR regulations, but EPA
expressed concern that the current record would not support a proposal
to approve the State's partial CCR permit program. Id. On February 17,
2023, ADEM responded to EPA that it did not intend to supplement the
record and that EPA should evaluate its program accordingly.\11\ EPA
thereafter continued to review the Application based on the information
submitted to date, and this notice reflects EPA's proposed conclusions
from that review.
---------------------------------------------------------------------------

    \9\ Letter from Alabama Attorney General Steve Marshall to EPA
Administrator Michael Regan, Notice of Endangerment and Intent to
Sue under Section 7002(a)(1)(A) and (1)(B) of the Resource
Conservation and Recovery Act. December 9, 2022.
    \10\ Letter from Barry Breen, Acting Assistant Administrator,
OLEM, to Lance LeFleur, Director, ADEM, February 1, 2023. Email sent
February 2, 2023.
    \11\ Letter from Lance LeFleur, Director, ADEM, to Barry Breen,
Acting Assistant Administrator, OLEM, February 17, 2023.
---------------------------------------------------------------------------

IV. EPA Analysis of the Alabama Application and Basis for Denial

    As stated above, a State seeking approval of a CCR permit program
can either adopt the Federal CCR requirements or establish State-
specific criteria that are at least as protective as the Federal CCR
requirements. See 42 U.S.C. 6945(d)(1)(B). After a State submits a
complete application, EPA evaluates the State program to determine
whether it ``requires each

coal combustion residuals unit located in the state to achieve
compliance with the applicable [Federal or other equally protective
State] criteria.'' Id. Specifically, EPA evaluates the terms of the
permit program or other system of prior approval and conditions and the
Narrative Statement, to determine whether by its terms the State
program meets either of these standards for each CCR unit regulated by
the State. As discussed in more detail below and in the TSD Volume III,
to make this determination EPA evaluates not only the CCR specific
requirements but also the State's general authority to issue permits
and impose conditions in those permits, as well as the State's
authority for compliance monitoring and enforcement.\12\ Thus,
collectively, the CCR specific and general permit requirements must
provide the State with sufficient authority to require compliance from
all CCR units located within the State. In addition, if the State
begins issuing CCR permits and overseeing compliance with the permits
prior to EPA's State program approval decision, the Agency must also
consider whether the State in fact ``requires each CCR unit located in
the state to achieve compliance with'' either the Federal criteria in
part 257 or other State criteria that ``are at least as protective as''
the Federal regulations. 42 U.S.C. 6945(d)(1)(B) (emphasis added). See
Unit IV.A of this preamble (discussing the Agency interpretation of
RCRA section 4005(d)).
---------------------------------------------------------------------------

    \12\ State permit program regulations usually include general
requirements that apply across multiple permit programs (e.g.,
procedures for issuing permits). When new performance standards are
issued for a type of facility or unit (for example, CCR
regulations), states include both general and facility/unit specific
requirements in the State permit program as necessary to develop a
program that satisfies the Federal requirements to support approval
of a State program.
---------------------------------------------------------------------------

    ADEM adopted regulations that largely mirror the Federal CCR
regulations, but in some places ADEM also added additional or different
criteria to be consistent with its existing solid waste regulations.
When a State adopts the language in the Federal CCR regulations, EPA's
review of the terms of the permit program is generally straightforward,
and, in this case, EPA's review of the express terms of ADEM's CCR
permit program demonstrates that the State program includes all
regulatory provisions required for approval of a partial program.\13\
Thus, the terms of the permit program provide ADEM with the authority
necessary to issue permits that will ensure each CCR unit in the State
achieves the minimum required level of control (i.e., the State has the
authority to issue permits that require compliance with standards that
are at least as protective as those in the Federal CCR regulations).
---------------------------------------------------------------------------

    \13\ EPA conducted a thorough review of the terms of Alabama's
CCR permit program submittal, consistent with review of submittals
by states that were granted approval, and that review can be found
in the Volume III: Technical Support Document for the Proposed
Notice to Deny Alabama's Coal Combustion Residuals Permit Program,
EPA Analysis of Alabama CCR Permitting and Technical Regulations.
U.S. Environmental Protection Agency, Office of Land and Emergency
Management (5304T), 1200 Pennsylvania Avenue NW, Washington, DC
20460. August 2023.
---------------------------------------------------------------------------

    While the statutes and regulations of the Alabama CCR permit
program provide the State with sufficient authority to require
compliance with the Federal requirements or equivalent State
requirements, EPA is proposing to determine that permits issued by ADEM
allow CCR units in the State to comply with alternative requirements
that are less protective than the requirements in the Federal CCR
regulations with respect to groundwater monitoring, corrective action,
and closure. For example, as discussed in more detail in subsequent
sections, ADEM has issued multiple permits allowing CCR in closed units
to remain saturated by groundwater, without requiring any engineering
measures to control the groundwater flowing into and out of the closed
unit. ADEM has also approved groundwater monitoring systems that
contain an inadequate number of wells, and in incorrect locations, to
detect groundwater contamination from the CCR units. Finally, ADEM has
issued multiple permits that effectively allow the permittee to delay
implementation of effective measures to remediate groundwater
contamination both on- and off-site of the facility. Overall, EPA's
review of the permit records demonstrates a consistent pattern of
deficiencies in the permits and a lack of oversight and independent
evaluation of facilities' proposed permit terms on the part of ADEM. In
each case, EPA was unable to locate any evaluation or record of
decision documenting that ADEM had critically evaluated the materials
submitted as part of the permit applications, or otherwise documented
its rationale for adopting those proposed permit terms prior to
approving the application. As a consequence, EPA cannot conclude that
the permits are as protective as the Federal CCR regulations.
    As noted above, EPA discussed many of these issues with ADEM and
the State declined to revise the permits to be consistent with the
Federal CCR regulations. ADEM also declined to demonstrate that its
alternative requirements satisfy the requirement in RCRA section
4005(d)(1)(B). Instead, the Alabama Attorney General, on behalf of
ADEM, asserted in the Notice of Intent to Sue that EPA does not have
the authority to consider implementation of the State program when
determining whether a State program is sufficient, and that the Agency
may only look to the ``four corners'' of the State program submission
when evaluating the program for approval. In the Notice of Intent to
Sue, the ``four corners'' of the application are described as being
public participation, guidelines for compliance, guidelines for
enforcement authority, and intervention in civil enforcement
proceedings. Regarding deficiencies in implementation of a State CCR
permit program, the State of Alabama's position must, therefore, be
that EPA first approve a State CCR permit program even if the Agency
knows the State's implementation is deficient prior to approval, and
the Agency must then follow the process for withdrawal of the program
through the program review and withdrawal provisions in RCRA sections
4005(d)(1)(D) and (E), respectively. Id.
    EPA does not agree with ADEM's interpretation of the Agency's
authority under RCRA, and the Agency is proposing to deny the program
under RCRA section 4005(d)(1)(B). Though the statute authorizes EPA to
approve a State CCR permit program in whole or in part, implementation
of the groundwater monitoring, corrective action, and closure
regulations are fundamental to an adequate CCR State permit program.
EPA does not see any meaningful way for a State to implement a partial
CCR permit program without the authority to oversee these three major
elements of the CCR program. Thus, EPA is proposing to deny the entire
Alabama CCR State permit program that ADEM submitted for approval.
    In Unit IV.A of this preamble, EPA responds to ADEM's position that
RCRA section 4005(d) prohibits EPA from considering the permits issued
under the State CCR permit program when determining whether to approve
the program and that EPA may only address such issues after the State
program is approved. In Unit IV.B of this preamble, the Agency provides
a short summary of EPA's conclusions after review of the express terms
of the ADEM statutes and regulations. In Unit IV.C of this preamble,
EPA identifies specific permits that the Agency believes are deficient
and explains the bases for EPA's proposed determination that they are
inconsistent with the standard for approval in RCRA section
4005(d)(1)(B).

A. Legal Authority To Evaluate State CCR Program Submittals

    For the reasons set forth below, EPA does not agree with ADEM's
assertion that EPA may not consider the State's CCR permit history when
determining whether to approve its permit program. In short, the Agency
interprets the statute to require EPA to consider the CCR permits a
State has issued under its CCR program when determining whether the
State program can be approved, where such information is available
prior to approval.
1. The Statute Requires EPA To Consider a State's CCR Permits When
Determining Whether To Approve the Program if the Information Is
Available
    Section 4005(d)(1)(B) of RCRA provides in part that the
Administrator ``shall approve, in whole or in part, a permit program or
other system of prior approval and conditions submitted under
subparagraph (A) if the Administrator determines that the program or
other system requires each coal combustion residuals unit located in
the State to achieve compliance with'' either: (1) The Federal CCR
requirements at 40 CFR part 257 (i.e., the Federal CCR regulations); or
(2) Other State criteria that the Administrator, after consultation
with the State, determines to be at least as protective as the Federal
requirements. 42 U.S.C. 6945(d)(1)(B) (emphasis added). The statute
directs the Administrator to determine whether the State program
``requires each'' CCR unit in the State ``to achieve compliance'' with
either the Federal standard or an alternative State standard at least
as protective as the Federal CCR regulations. This necessarily includes
Agency consideration of both a State's statute and regulations and what
the State actually requires individual CCR units to do, such as in
permits or orders, when such information is available prior to approval
of the State program. By specifying that EPA is to determine that the
State program requires each unit ``to achieve compliance,'' rather than
merely that the State requires compliance or has the authority to
require compliance, Congress indicated that EPA is not restricted to
evaluating the letter of the State's regulations. Moreover, the statute
makes clear that once a permit goes into effect, those are the relevant
requirements applicable to the CCR unit rather than the regulations.
See 42 U.S.C. 6945(d)(3) (specifying that the applicable criteria for
CCR units in an approved State are those contained in the State permit,
rather than the Federal or State regulations). Whether issued permits
comply with Federal requirements or a State program that is at least as
protective is directly relevant to whether the State program ``requires
each CCR unit in the State to achieve compliance.'' If issued permits
do not comply, the State program does not require compliance. EPA
cannot reasonably ignore such information, when available, as it falls
squarely within the ordinary meaning of what the statute expressly
directs EPA to consider. This is particularly true, where, as here, the
Agency knows ADEM is issuing permits to CCR units that do not require
compliance with the Federal CCR regulations, and the State has not
demonstrated that its alternative approach is as protective as the
Federal CCR regulations.
    In this case, ADEM adopted into its State regulations the
provisions of the Federal CCR regulations. For this reason, ADEM
believes that EPA must approve the State's CCR program because it in
large part mirrors to the Federal CCR regulations, thus, according to
ADEM, the State program satisfies the requirements for an approvable
program pursuant to RCRA section 4005(d)(1)(B)(i). ADEM is correct that
EPA may approve a State program under this provision based on the fact
that the State's regulations are identical to those in the Federal CCR
regulations, but not where the State interprets the State regulations
to impose significantly different requirements than the Federal CCR
regulations, and the State has issued permits authorizing actions that
the Federal regulations prohibit. Here, despite adopting the language
in the Federal CCR regulations, ADEM has affirmatively stated that it
interprets the State regulations differently than the identically
worded Federal provisions and has issued permits on that basis, even
though the Agency has informed the State on multiple occasions that its
interpretation and implementation of the regulations are not consistent
with the Federal CCR regulations. See Units III.E and IV.C of this
preamble (discussing Alabama's interpretation of ``infiltration'' under
Sec.  257.102(d)(1)(i), among other examples). Based on all of the
information in the record, EPA cannot conclude that Alabama's program
``requires each'' CCR unit in the State ``to achieve compliance with''
the Federal CCR regulations as required by RCRA section
4005(d)(1)(B)(i).
    Further, because Alabama is interpreting the language in the
Federal CCR regulations differently than the Agency, Alabama is
essentially submitting ``other State criteria,'' and in order for EPA
to approve such a program, Alabama must provide information to support
a determination that the State criteria are ``at least as protective as
the [Federal CCR regulations]'' consistent with RCRA section
4005(d)(1)(B)(ii). EPA has explained its position to Alabama, most
recently by letter dated February 1, 2023, and Alabama has declined to
provide any explanation, much less an adequate one, of how its program
will require each CCR unit to achieve compliance with standards at
least as protective as the Federal CCR regulations. Accordingly, the
Agency is proposing to deny Alabama's request for approval of its CCR
permit program. This proposed denial is based on all the available
information in the record, and as discussed in Unit IV.C of this
preamble, it demonstrates that the Alabama CCR permits do not require
each CCR unit in the State to achieve compliance with requirements at
least as protective as those contained in the Federal CCR regulations.
2. EPA Is Not Required To Approve a Deficient State Program and Then
Redress the Deficiencies Through RCRA's Program Review Provisions
    In addition to the express terms of RCRA section 4005(d)(1)(B), as
explained below, the overall context of RCRA section 4005(d) supports
consideration of State CCR permits when they have been issued prior to
approval of the State program. Even were that not the case, it would be
unreasonable to interpret the statute to require that EPA must approve
a State program based on the four corners of the submission and then
use the program review provisions of RCRA section 4005(d)(1)(D) to
address pre-existing deficiencies in the program. As an initial matter,
EPA questions how it would be reasonable to ignore directly relevant
and readily available information in review of a State program that
will stand in for a Federal program, because once EPA approves a State
program, the requirements of the State program apply instead of the
Federal rules. Further, once a State permit is issued, facilities are
shielded from enforcement of anything other than the provisions of the
State permit. Compounding the problem is the time it would take to go
through the statutorily mandated process to withdraw a deficient
program and the fact that prior noncompliance would be arguably
sanctioned by approval of a State program that is being implemented
improperly.
    In this case, all the potential problems that can arise by
approving a State CCR program based solely on the ``four

corners'' of the State application are in play. Specifically, the State
is interpreting the terms of the State program (i.e., the terms of the
Federal CCR regulations) in a manner that is less protective than the
Federal CCR regulations, the State is issuing permits based on its
flawed interpretation, EPA approval of the State program would be the
equivalent of approving the deficient permits, it would take
considerable time to withdraw the State program after approval, and, in
the interim, facilities would be able to operate under permits that are
less protective than required. Furthermore, the Agency is proposing to
determine, based on the available information, that Alabama's CCR
permit program is deficient under two of the bases provided in RCRA
section 4005(d)(1)(D)(ii), EPA has notified Alabama of the
deficiencies, and the State has declined to address them. See Unit IV.C
of this preamble (discussing the deficiencies in Alabama's CCR
program).
    The statute requires EPA to periodically review approved State
programs and provides a process by which EPA can address identified
deficiencies. RCRA sections 4005(d)(1)(D)(i) and 4005(d)(1)(D)(ii),
respectively. The review provisions in RCRA section 4005(d)(1)(D)(i)
require review:
     from time to time, as the Administrator determines
necessary, but not less frequently than once every 12 years;
     not later than 3 years after the date on which the
Administrator revises 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);
     not later than 1 year after the date of a significant
release (as defined by the Administrator), that was not authorized at
the time the release occurred, from a coal combustion residuals unit
located in the State; and
     on request of any other State that asserts that the soil,
groundwater, or surface water of the State is or is likely to be
adversely affected by a release or potential release from a coal
combustion residuals unit located in the State for which the program or
other system was approved.
    The statute clearly provides for review of State programs whenever
``the Administrator determines necessary,'' in addition to the
situations that mandate EPA review of a State program (e.g., RCRA
section 4005(d)(1)(D)(i)(I) requiring review periodically and at least
every 12 years). Under Alabama's reading of the statute, EPA must
approve a knowingly deficient State program and then undertake a
program review, either mandatory or discretionary, to address the
deficiencies in that same program. Under such circumstances, CCR units
in the State would potentially be allowed to operate in a manner that
is not consistent with the Federal CCR regulations for many years
unless EPA were to undertake a voluntary program review immediately
after approving the program.
    An additional factor that argues against Alabama's interpretation
is the fact that RCRA section 4005(d)(1)(D)(ii) provides a process that
EPA must follow to address identified deficiencies in a State CCR
permit program before EPA may withdraw the program, and, during that
time, ADEM could continue to issue permits that are not as protective
as the statute requires. See also 42 U.S.C. 6945(d)(1)(E)(i) (allowing
withdrawal of a State program only after notice to the State and an
opportunity for a hearing). Specifically, under RCRA section
4005(d)(1)(D)(ii), EPA must provide the State with notice of
deficiencies in the State program and an opportunity for a hearing if
the Administrator determines that:
     a revision or correction to the permit program or other
system of prior approval and conditions of the State is necessary to
ensure that the permit program or other system of prior approval and
conditions continues to ensure that each coal combustion residuals unit
located in the State achieves compliance with the criteria described in
clauses (i) and (ii) of subparagraph (B);
     the State has not implemented an adequate permit program
or other system of prior approval and conditions that requires each
coal combustion residuals unit located in the State to achieve
compliance with the criteria described in subparagraph (B); or
     the State has, at any time, approved or failed to revoke a
permit for a coal combustion residuals unit, a release from which
adversely affects or is likely to adversely affect the soil,
groundwater, or surface water of another State.
    The information currently available to EPA already indicates that
Alabama's program is deficient under the first two provisions of RCRA
section 4005(d)(1)(D)(ii). First, a revision to Alabama's CCR permit
program is necessary to ensure that each CCR unit located in the State
achieves compliance with State standards that are ``at least as
protective as'' the Federal CCR regulations because Alabama has never
adequately explained how its alternative requirements achieve that
standard. 42 U.S.C. 6945(d)(1)(D)(ii)(I). Second, as explained further
in Unit IV.C. of this preamble, ADEM has not implemented its permit
program in a manner that ``ensures each CCR unit located in the State
achieves compliance with the criteria described in subparagraph (B).''
42 U.S.C. 6945(d)(1)(D)(ii)(II). In addition, EPA has notified Alabama
of these deficiencies on multiple occasions, and the State has not
provided an adequate justification for the position that its
interpretation of the Federal CCR regulations should govern over EPA's
interpretation.
    Given Alabama's continued failure to adequately address EPA's
concerns with its CCR program, EPA has no reason to believe that
Alabama will change its interpretation and implementation of its
program if EPA were to approve Alabama's CCR program and then
subsequently proceed with the RCRA section 4005(d)(1)(D)(ii) process to
attempt to resolve the program deficiencies. EPA would then have to go
through the RCRA section 4005(d)(1)(E) process to withdraw the Alabama
program. In that case, EPA would then be back at the point where
Alabama would have to either adopt EPA's interpretation of the Federal
CCR regulations or explain how its alternative interpretation ensures
that the State's program is as least as protective as the Federal CCR
regulations.
    The statutory language is clear, and it does not support Alabama's
interpretation. In addition, the Agency believes Alabama's
interpretation could, as in this case, lead to the illogical result
that EPA must approve a State CCR permit program that it believes it
likely will eventually have to withdraw. EPA also declines to adopt
Alabama's suggested approach because the process to withdraw takes
significant time and in the interim Alabama would likely continue to
issue permits that allow CCR units in the State to operate under
conditions that are less protective than those required in the Federal
CCR regulations. Finally, EPA is aware of several CCR permits that
allow units to operate less protectively than required by Federal CCR
regulations and approving Alabama's program would mean that these units
would no longer be subject to the Federal CCR regulations. Thus, if EPA
were to approve Alabama's program now (i.e., after the deficient CCR
permits were issued), the Alabama CCR program, including the facility-
specific permits, would apply in lieu of the Federal CCR

regulations pursuant to RCRA section 4005(d)(1)(A) and (3).
    For all these reasons, EPA does not believe the statute must be
interpreted as Alabama suggests and EPA declines to adopt the State's
interpretation.

B. EPA's Analysis of the Alabama CCR Regulations

    Section 4005(d)(1)(A) of RCRA, 42 U.S.C. 6945(d)(1)(A), requires a
State seeking CCR permit program approval to submit to EPA, ``in such
form as the Administrator may establish, evidence of a permit program
or other system of prior approval and conditions under State law for
regulation by the State of coal combustion residuals units that are
located in the State.'' Although the statute directs EPA to establish
the form of such evidence, the statute does not require EPA to
promulgate regulations governing the process or standard for
determining the adequacy of such State programs. EPA, therefore,
developed the Coal Combustion Residuals State Permit Program Guidance
Document; Interim Final (82 FR 38685, August 15, 2017) (the ``Guidance
Document''). The Guidance Document provides recommendations on a
process and standards that states may choose to use to apply for EPA
approval of a State CCR permit program, based on the standards in RCRA
section 4005(d), existing regulations at 40 CFR part 239, and the
Agency's experience in reviewing and approving State programs.
    As stated above, State permit programs under RCRA generally include
both sector specific technical regulations (e.g., performance standards
for CCR units) and general State permitting and enforcement provisions
that apply to all the different State RCRA permitting programs. In this
case, Alabama is seeking approval of a partial State CCR permit program
and it established State regulations that are almost the same as the
Federal CCR regulations for the portions of the Federal program for
which the State is seeking approval. To the extent the Federal and
State provisions are different, the differences do not on their face
substantively make the State regulations less protective than the
Federal CCR regulations. EPA reviewed ADEM's CCR regulations and, based
on that review, EPA proposes to find that the express terms of the
regulations provide ADEM with sufficient authority to issue permits
that are at least as protective as those required under the Federal CCR
regulations. See the TSD Volume III (providing a detailed analysis of
the regulatory terms of Alabama's CCR regulations). EPA is proposing to
determine that the terms of the regulations provide the State with
sufficient authority to implement an adequate CCR permit program
despite the fact that the Agency is also proposing to deny the
Application for Alabama CCR permit program based on the State's
issuance of permits under those same regulations. Therefore, the Agency
believes the record would support approval of Alabama's program if the
State either modified its permits to be consistent with the Federal
requirements or demonstrated that its alternative requirements are at
least as protective as the Federal CCR regulations.
    EPA briefly discusses its evaluation of the State's regulations
below. A comprehensive evaluation is included in the TSD Volume III in
the docket for this proposed action.
1. Adequacy of Technical Criteria
a. Alabama CCR Regulations
    EPA first evaluates the technical criteria that will be included in
each permit the State issues to determine whether they are the same as
the Federal criteria, or to the extent they differ, whether the
modified criteria are ``at least as protective as'' the Federal
requirements. See 42 U.S.C. 6945(d)(1)(B).
    On April 20, 2018, ADEM, by and through the Alabama Environmental
Management Commission (EMC), amended ADEM Admin. Code div. 335-13 to:
(1) Modify Chapters 1, 4, and 5 and (2) Add a new Chapter 15: Standards
for the Disposal of Coal Combustion Residuals in Landfills and Surface
Impoundments. These rules became effective on June 8, 2018. In response
to EPA comments and changes to the Federal CCR regulations, ADEM
proposed and finalized several amendments to its CCR rules with the
first revisions becoming effective February 15, 2021. The most recent
revisions became effective December 13, 2021.
    ADEM's regulations adopt the Federal CCR regulations amended
through August 28, 2020, and include the corrections EPA made at
Sec. Sec.  257.102(d)(3)(ii) and 257.103(f)(1)(vi) (85 FR 72506,
November 12, 2020) (except for certain provisions outlined below).
    EPA has preliminarily determined that the Alabama CCR permit
program contains all the technical criteria in 40 CFR part 257, subpart
D, except for the provisions specifically discussed below. EPA's full
analysis of the terms of the Alabama CCR permit program and how the
Alabama regulations differ from the Federal requirements can be found
in the TSD Volume III.
b. Federal Rule Provisions Excluded From Alabama's Request for Approval
of a Partial Program
    Alabama is requesting approval for a partial State CCR program,
rather than a full CCR program that includes all the requirements of
the Federal CCR regulations. ADEM is not seeking approval for the
following six provisions:
    1. ADEM Administrative Code r. 335-13-15-.01(1)(d); this State
provision is the analog to the Federal exclusion of inactive surface
impoundments at inactive facilities, found at Sec.  257.50(e), that was
vacated in Utility Solid Waste Activities Group v. EPA, 901 F.3d 414
(per curiam) (USWAG);
    2. ADEM Admin. Code r. 335-13-15-.07(4)(f); this State provision is
the analog to the Federal requirement for alternative closure
deadlines, found at 40 CFR 257.103(f);
    3. EPA has revised the Federal regulations to granting
Participating State Directors authority to issue certifications in lieu
of requiring a professional engineer (PE) certification. ADEM did not
adopt these provisions; therefore, an owner or operator of a CCR unit
must submit certifications from a PE, as appropriate, as required by
ADEM Admin. Code chapter 335-13-15;
    4. The Federal regulations include a provision that authorizes the
suspension of groundwater monitoring requirements under certain
circumstances, found at Sec.  257.90(g), which the State has not
adopted;
    5. The Federal regulations include a provision for an alternate
liner demonstration found at Sec.  257.71(d), and the State has not
adopted this Federal provision; and,
    6. ADEM Admin. Code r. 335-13-15-.06(6)(h)2.: The State has adopted
the groundwater protection standards for cobalt, lead, lithium, and
molybdenum found at Sec.  257.95(h)(2) but is not seeking approval
because the Federal provision has been challenged and is under
reconsideration.
    More detail on the elements of the partial program and EPA's
analysis of the program can be found in the TSD Volume III. With the
exception of specific provisions spelled out in the TSD Volume III, EPA
has preliminarily determined that the Alabama CCR regulations contain
all the technical elements of the portions of the Federal CCR
regulations for which the State is seeking approval.

2. Review of Generally Applicable Alabama CCR Permit Program Statutes
and Regulations
    As explained above, supra note 12, Alabama's CCR permit program
regulations include general requirements that apply across multiple
permit programs, and its Application for approval of a CCR permit
program thus includes both general and facility/unit-specific
requirements in the State CCR permit program. EPA therefore also
evaluated the Alabama CCR permit program as modified to address CCR
units using the process discussed in Units II.C and IV.A of this
preamble. EPA's findings are summarized below and provided in more
detail in in the TSD Volume III for this notice.
    In evaluating Alabama's CCR permitting requirements, EPA reviewed
the State's permit requirements for CCR units including applicability,
duration, application process, denial process, and the process for
draft and final permit determinations. EPA also reviewed Alabama's
requirements that apply to modification, suspension, and revocation of
permits. For permit modifications, EPA specifically looked at major and
minor modifications to determine which modifications would require
public participation. After conducting this review, EPA has
preliminarily determined that the Alabama regulations concerning CCR
permit applications and approvals is adequate, and that this aspect of
the Alabama CCR permit program meets the standard for program approval.
    Based on RCRA section 7004, 42 U.S.C. 6974, it is EPA's judgment
that an adequate State CCR permit program will ensure that: (1)
Documents for permit determinations are made available for public
review and comment; (2) Final determinations on permit applications are
made known to the public; and (3) Public comments on permit
determinations are considered. Alabama has adopted public participation
opportunities for the CCR program that can provide an inclusive
dialogue, allowing interested parties to talk openly and frankly about
issues within the CCR program and search for mutually agreeable
solutions to differences. EPA reviewed Alabama's public participation
requirements, processes, and procedures including public notices,
public comment periods (including consideration of public comments),
public hearings, and public availability of final determinations. An
overview of the Alabama public participation provisions is provided in
the TSD Volume III. After conducting this review, EPA has preliminarily
determined that the Alabama approach to public participation
requirements provides adequate opportunities for public participation
in the permitting process sufficient to meet the standard for program
approval.
    EPA also reviewed Alabama's compliance monitoring authority,
enforcement authority, and the procedures for intervention in civil
enforcement proceedings. It is EPA's judgment that an adequate permit
program should provide the State with the authority to gather
information about compliance, perform inspections, and ensure that
information it gathers provides an adequate basis for enforcement.
ADEM's statutory authority for compliance monitoring for its Solid
Waste Program is set forth in sections 22-27-7, 22-27-9, 22-27-12, 22-
22A-5 and 22-22A-8 of the Code of Alabama, 1975. These portions of the
statute, as well as ADEM Admin. Code rules 335-13-1-.11(2) and 335-13-
6-.01(2) give the Department authority during an inspection to obtain
all information necessary to determine whether the owner/operator is in
compliance with State CCR requirements. This includes authority to
conduct monitoring and testing when necessary.
    Based on the information Alabama has submitted on the State's
permitting requirements, EPA has preliminarily determined these aspects
of the Alabama CCR permit program provide the State with the necessary
authority to implement an adequate State program. More detail on the
review and analysis of Alabama's CCR permit program can be found in the
TSD Volume III.

C. EPA's Analysis of Alabama's Permits Issued Under the State CCR
Regulations

    EPA conducted a review of Alabama's permitting decisions as part of
the Agency's evaluation of whether ADEM's CCR permit program requires
each coal combustion residual unit located in the State to achieve
compliance with standards at least as protective as the Federal CCR
regulations. 42 U.S.C. 6945(d)(1)(B). Alabama's permitting decisions
issued under its CCR regulations are directly relevant to determining
whether the State's program satisfies this statutory requirement, and
EPA considers such information to be appropriately part of the record
for a decision on the permit program when permit issuance begins prior
to approval of the State program and the Agency has information that
the State's implementation is not sufficiently protective.
    ADEM submitted its revised State CCR permit program Application on
December 29, 2021. Less than a month later, on January 11, 2022, EPA
published several proposed decisions responding to requests from owners
and operators of CCR units nationwide for extensions of the April 11,
2021, deadline to cease sending waste to unlined CCR surface
impoundments (Part A proposals). EPA proposed to deny several of the
extension requests because facilities were planning to close unlined
CCR surface impoundments with, among other things, waste remaining in
groundwater without adopting engineering measures to limit the flow of
groundwater into and out of the unit. Soon after issuing the Part A
proposals, several states, utility facilities that own unlined surface
impoundments, and trade groups contacted EPA to object to the Agency's
application of the closure requirements to the unlined surface
impoundments in those proposed decisions. Based on these objections,
EPA was concerned that Alabama's and other states' CCR permit programs
were being interpreted and implemented to allow facilities to close
unlined surface impoundments without complying with all the necessary
requirements in the Federal regulations.
    Because of these concerns, on March 15, 2022, EPA sent a list to
ADEM of CCR surface impoundments in Alabama that, based on the
information available to EPA, appear to be inundated by
groundwater.\14\ Over the next several months, EPA and ADEM met several
times to discuss the application of the Federal closure performance
standards to such impoundments, and to better understand how the State
interpreted its own requirements.\15\
---------------------------------------------------------------------------

    \14\ The CCR surface impoundments with insufficient permits that
are discussed in this Unit of the preamble are all surface
impoundments with WBWT. For a list of all the CCR surface
impoundments EPA identified in Alabama with WBWT, see Email from
Meredith Anderson to Scott Story. CCR units in AL. March 15, 2022.
    \15\ Interactions between EPA and Alabama about implementation
of the State program include: April 13, 2022, meeting to discuss the
Federal closure performance standards; three separate meetings to
discuss the proposed closure requirements for Plant Gorgas, Plant
Greene County, and Plant Gadsden; May 10, 2022, meeting to further
discuss the closure performance standard and specifically how ADEM
was interpreting and applying the closure and groundwater monitoring
performance standards at the Ash Pond at Plant Gadsden; and May 28,
2022, meeting to discuss the status of closure activities at Plant
Greene County and Plant Gadsden. A list of EPA/Alabama interactions
is in the Technical Support Document Volume II.
---------------------------------------------------------------------------

    EPA also started reviewing permits for unlined surface impoundments
in Alabama as part of EPA's review of the State CCR permit program. As
a consequence, in meetings and in correspondence with ADEM, EPA

expressed concern that Alabama's permit program appeared to differ from
the Federal program, and that these differences appeared to make the
State's program less protective than the Federal program. As a result
of these discussions, on July 7, 2022, EPA informed ADEM via telephone
that EPA would be unable to approve ADEM's CCR permit program
Application until Alabama demonstrated to EPA that the State is
implementing its program to be as protective as the Federal CCR
regulations.\16\ Further, EPA explained to ADEM that it was exploring
options for actions to take at the Federal level with respect to both
the CCR permit program Application and at specific facilities where
there are outstanding concerns.
---------------------------------------------------------------------------

    \16\ July 7, 2022- Telephone call between Carolyn Hoskinson,
Director of EPA's Office of Resource Conservation and Recovery, and
Stephen Cobb, Chief of the Land Division at the Alabama Department
of Environmental Management.
---------------------------------------------------------------------------

    Throughout the course of these discussions, and in EPA's nationwide
Part A determinations, EPA explained the existing requirements under
the Federal regulations; in response, ADEM offered notably different
interpretations of some of the obligations under the State's current
closure requirements. Despite the Agency's concerns, the State
continues to implement its CCR program in a manner that is less
protective than the Federal CCR regulations, and Alabama has not
adequately explained how its alternative State program satisfies the
statutory requirement to require each CCR unit in the State to achieve
compliance with either the Federal requirements or with State standards
that are at least as protective as the Federal requirements.
    As part of the evaluation of Alabama's CCR program submittal, EPA
reviewed four final State CCR permits issued by ADEM for the following
facilities: Plants Colbert, Gadsden, Greene County, and Gorgas. EPA's
review focused specifically on permits issued to unlined surface
impoundments that have closed or are closing with waste that will
remain in place below the water table, because these units have the
greatest potential to cause significant environmental and human health
effects if mismanaged. EPA limited its review to information in the
permit record (e.g., the Permit Application or information on ADEM's e-
File site) and to information publicly available on each facility's CCR
website, even though the permit record alone should contain all the
information necessary to determine whether the permit is as protective
as the Federal CCR regulations. EPA also did not attempt to catalog
every potential inconsistency between the permits and the Federal CCR
regulations. Instead, EPA concentrated on the permits' consistency with
fundamental aspects of the closure, groundwater monitoring, and
corrective action requirements. EPA took this approach because the
purpose of this review is to determine whether Alabama's program meets
the statutory standard for approval, not to reach final conclusions
about an individual facility's compliance with the CCR regulations.
    During its review, EPA identified a consistent pattern of ADEM
issuing permits to CCR units that fail to demonstrate compliance with
fundamental requirements in part 257, without requiring the permittees
to take specific actions to bring the units into compliance. EPA also
identified a consistent pattern of ADEM approving documents submitted
by the facilities, such as closure plans, groundwater monitoring plans,
and assessments of corrective measures, even though the submissions
lacked critical information or are otherwise deficient. ADEM also did
not require the permittees to take any action to cure deficiencies in
the permits even where ADEM previously identified the deficiencies and
requested further information prior to issuing the final permits.
Specifically, EPA is proposing to determine that ADEM issued multiple
permits allowing CCR in closed units to remain saturated by
groundwater, without requiring engineering measures that will control
the groundwater flowing into and out of the closed unit. See, 40 CFR
257.102(d). EPA is also proposing to determine that ADEM approved
groundwater monitoring systems that contain an inadequate number of
wells, and in incorrect locations, to monitor all potential contaminant
pathways and to detect groundwater contamination from the CCR units in
the uppermost aquifer. See, 40 CFR 257.91. Finally, EPA is proposing to
determine that ADEM issued multiple permits that effectively allow the
permittee to delay implementation of effective measures to remediate
groundwater contamination both on- and off-site of the facility. See,
40 CFR 257.96-257.97. Overall, EPA's review of the permit records and
other readily available information documents a consistent pattern of
deficient permits and a lack of oversight and independent evaluation of
facilities' proposed permit terms. In each case, EPA was unable to
locate any evaluation or record of decision documenting that ADEM
critically evaluated the materials submitted as part of the permit
application, or otherwise documented its rationale for adopting them.
For all these reasons, EPA is proposing to conclude that the ADEM
permits discussed below are not as protective as the Federal CCR
regulations.
    In the next several sections, EPA discusses specific issues
identified during the review of ADEM's final permits for Plants
Colbert, Gadsden, Greene County, and Gorgas.\17\ Based on EPA's review,
the Agency is proposing to deny Alabama's Application because the
State's CCR permit program does not require each CCR unit in the State
to achieve compliance with either the minimum requirements in the
Federal CCR regulations or with alternative requirements that EPA has
determined to be at least as protective as the Federal provisions.
---------------------------------------------------------------------------

    \17\ On January 31, 2023, EPA Region 4 sent a Notice of
Potential Violations (NOPV) and Opportunity to Confer to Alabama
Power Company. The NOPV addressed concerns with compliance of
Alabama Power Company's Plant Barry Ash Pond. The NOPV addressed the
following potential violations: failure to meet the criteria for
conducting the closure of the Plant Barry Ash Pond, failure to
establish an adequate groundwater monitoring system, and failure to
address certain site-specific criteria in the Emergency Action Plan.
Although the permit and record for Plant Barry share many of the
flaws in the CCR permits for other unlined surface impoundments in
Alabama, EPA will not address the Plant Barry permit as part of this
action because the enforcement process with the facility is ongoing.
---------------------------------------------------------------------------

1. Colbert Fossil Plant
    TVA owns and operates the Colbert Fossil Plant (Colbert or Colbert
Plant) located in Colbert County, Alabama, and it submitted a permit
application for the facility dated December 10, 2021.\18\ The plant
property is on the south bank of the Tennessee River, approximately 8
miles west of Tuscumbia, Alabama. The Colbert Fossil Plant was fully
idled and stopped generating electricity in March 2016. The plant had
five generating units with a combined generating capacity of 1,204
megawatts. In accordance with the ADEM Land Division, Solid Waste
Program, Standards for Disposal of Coal Combustion Residuals in
Landfills and Surface Impoundments, Chapter 335-13-15-.02, Ash Disposal
Area 4 (also called Ash Pond 4) is classified as an existing CCR
surface impoundment. Ash Disposal Area 4 is located on the southern
portion of the plant property, approximately 3,000 feet south of the
powerhouse. The CCR surface impoundment is bounded to the west by
Colbert Steam Plant Road, to the east by Cane Creek, and to the south
by Lee Highway. EPA reviewed TVA's permit application and draft and
final permits

for the Colbert Plant along with associated documents. Issues with
closure, groundwater monitoring networks, and corrective action at the
Colbert Plant are discussed below.
---------------------------------------------------------------------------

    \18\ Tennessee Valley Authority Colbert Fossil Plant (COF) Ash
Pond 4 Permit Application. Submitted to ADEM. December 10, 2021.
---------------------------------------------------------------------------

a. TVA Colbert Closure Issues
    The Federal CCR regulations provide two options for closing a CCR
unit: closure by removal and closure with waste in place. 40 CFR
257.102(a). Both options establish specific performance standards. 40
CFR 257.102(c) and (d). TVA closed Ash Pond 4 at Colbert by leaving the
CCR in the unit in place; but, as explained below, the TVA application
for Ash Pond 4 did not comply with the Federal closure standards for
closure with waste in place for unlined surface impoundments and ADEM
issued the permit without addressing the deficiencies.
    TVA's Permit Application for the Colbert Plant explains that Ash
Pond 4 was built in 1972 and TVA completed its closure in early 2018,
prior to its application for a permit under the ADEM CCR rules in
Chapter 335-13-15.\19\ TVA elected to close Ash Pond 4 by leaving CCR
in place and constructing a final cover system over the waste, which is
estimated to be 2.6 million cubic yards (CY) of waste.\20\ Closure of
Ash Pond 4 was completed in accordance with a closure and post-closure
care plan dated February 2017, which was approved by ADEM on August 22,
2017.\21\ Closure activities were deemed complete in March 2018 and a
certification report dated September 18, 2018, documenting closure of
Ash Disposal Area 4, was submitted to ADEM.
---------------------------------------------------------------------------

    \19\ The terms ``Ash Pond 4'' and ``Ash Pond Area 4'' are both
used in the Colbert Plant Permit Application to refer to the
impoundment in question. For purposes of this proposal, EPA is
referring to the impoundment as Ash Pond 4.
    \20\ The Permit Application states that the ``total capacity of
Ash Disposal Area 4 is approximately 2.6 million CY, covering
approximately 52 acres.'' EPA is aware that other reports State that
the ``approximate volume of CCR material at the time of the
inspection'' is 3.29 million CY. See, e.g., FY2021 Intermediate
Inspection of CCR Facilities dated May 6, 2021. For purposes of
estimating volumes of saturated CCR in this proposal, EPA is taking
an approach that provides a minimum estimate, relying on the value
presented in the Permit Application to represent the volume of CCR
in the impoundment, instead of relying on the larger estimates
established based on the inspection of the unit.
    \21\ Tennessee Valley Authority. Permit Application for CCR
Surface Impoundment, TVA Colbert Fossil Plant Ash Disposal Area 4.
December 10, 2021. Attachment I.
---------------------------------------------------------------------------

    ADEM's Final Permit, issued in October 2022, provides the following
terms and conditions:
    Closure Timeframe and Notifications. The Permittee shall close
their CCR units as specified in 335-13-15-.07(2), this permit and the
Application.
    B. Criteria for Closure.
    1. Cover. Closure of a CCR landfill, surface impoundment, or any
lateral expansion of a CCR unit must be completed by either leaving the
CCR in place and installing a final cover system or through removal of
the CCR and decontamination of the CCR unit, as described in 335-13-
15-.07(3)(b) through (j). The minimum and maximum final grade of the
final cover system may be less than 5 percent and greater than 25
percent, as specified in the Permit Application, for the Colbert Fossil
Plant Ash Disposal Area 4. Ash Disposal Area 4 may utilize erosion
control measures, as specified in the Permit Application, other than
horizontal terraces. (See Section IX.A. and B.)
    2. Written Closure Plan. The written closure plan, as part of the
Application, must include, at a minimum, the information specified in
335-13-15-.07(3)(b)1.(i) through (vi).
    According to ADEM, ``[t]he Department adopted the terms of the
closure plan as part of the permit as the Department has previously
approved the plan and determined it meets both State and Federal
regulations for closure of a CCR unit.'' \22\ Once ADEM approved and
adopted TVA's Closure Plan into the permit, the Closure Plan, rather
than the referenced State regulations, became the State requirements
with which TVA is required to comply. See, 42 U.S.C. 6945(d)(3)(A). As
discussed in detail in the next section and summarized in Table II,
between 2019 and 2021, approximately 6 to 13 feet of ash (on average)-
or 13 to 35 percent of the CCR in the closed Ash Pond remains saturated
by groundwater.
---------------------------------------------------------------------------

    \22\ Letter from Stephen Cobb to Carolyn Hoskinson, Responding
to EPA Comments on Proposed Permit for the
    Tennessee Valley Authority Colbert Fossil Plant, October 27,
2022, Enclosure 1, page 6.
---------------------------------------------------------------------------

i. The CCR in the Closed Ash Pond 4 Remains Saturated by Groundwater
    Neither TVA's Closure Plan, the Permit Application, ADEM's Final
Permit, or any other document in the permitting record specifically
discuss how the closure of Ash Pond 4 would meet the closure
performance standards given the measured groundwater elevations and
hydrogeology of the site. Accordingly, EPA reviewed information in the
Permit Application as well as other publicly available information
available on TVA's CCR website to determine whether groundwater remains
in contact with the CCR in Ash Pond 4 since closure was completed in
March 2018. As described below, available groundwater measurements
recorded between 2018 and 2021 show that, even after closure,
groundwater levels at Ash Pond 4 continue to be present above the base
of the unlined impoundment, saturating a portion of the CCR in the
closed unit. EPA's basis for these findings is described in the
succeeding paragraphs, which summarize EPA's understanding of the base
elevation of Ash Pond 4 (e.g., the lowest extent of CCR in the unit),
the groundwater levels since closure was completed in 2018, and EPA's
estimate of the volume of CCR that remains saturated with liquid
(groundwater). More details on EPA's analyses can be found in TSD
Volume I.\23\
---------------------------------------------------------------------------

    \23\ Volume I: Technical Support Document for the Proposed
Notice to Deny Alabama's Coal Combustion Residuals Permit Program,
Supplemental Analyses of Technical Issues with ADEM Permits. U.S.
Environmental Protection Agency, Office of Land and Emergency
Management (5304T), 1200 Pennsylvania Avenue NW, Washington, DC
20460. August 2023.
---------------------------------------------------------------------------

(1) Base of the Impoundment
    Ash Pond 4 is a 52-acre CCR surface impoundment that was created by
constructing a single dike around the perimeter of the impoundment and
two internal divider dikes. EPA was unable to locate information in the
Permit Application or other publicly available documents that fully
describes the as-constructed configuration of the bottom of Ash Pond 4
across its entire footprint prior to the initial receipt of waste.
However, based on information in the Permit Application and documents
referenced in the Permit Application, the lowermost documented
elevations at which CCR occurs within the impoundment varies depending
on the location, ranging from approximately 413.5 to 427.1 ft above
mean sea level (MSL). See TSD Volume I, Section II.a.
    EPA also relied on an average elevation to estimate the volume of
CCR in the impoundment remaining in contact with groundwater, rather
than trying to account for what may be as much as a 14-foot difference
across the 52-acre impoundment. Specifically, EPA relied on an average
bottom elevation of 422 ft above MSL, which is the average of elevation
measurements taken at 18 locations within the footprint of the
impoundment based on borings for piezometers and wells. Information on
these borings is found on construction drawings 10W395-7 through 9 and
a report from 2010. See TSD Volume I, Section II.a. This average is
also consistent with several documents in the Permit Application and
other documents that depict the

base of the impoundment at 422 ft above MSL. For example, Section A-A
of construction drawing 10N292R3 shows a bottom elevation of
approximately 422 ft above MSL in the vicinity of the northern
perimeter dike where the spillways were constructed. Id. at Volume I,
Section II.a.i.3. Another example is a slope stability section
supporting a steady-state seepage analysis that shows a portion of the
base of the impoundment to be at an elevation of 422 ft above MSL. Id.
at Section II.a.i.2. Similarly, design drawings from 2010 for a
temporary rock buttress and sheet pile wall constructed in a portion of
an internal divider dike show the bottom of the impoundment to be 422
ft above MSL at this location. Id. at Section II.a.i.3. A final example
is the liner design demonstration prepared by TVA to comply with Sec.
257.71 that states ``[f]rom information contained in drawing 10N290, it
was assumed the base of the pond is at elevation 422 ft.'' Id. at
Section II.a.iv. However, it is important to note that the use of the
422 ft elevation mark to represent the base of the unit was an effort
to represent average conditions. As noted earlier, the preponderance of
the evidence suggests that base of the impoundment varies depending on
the location, ranging from approximately 413.5 to 427.1 ft above MSL,
but an average value of 422 ft above MSL is technically defensible and
conservatively high. See TSD Volume I, Section II.a. Volumes during
worst case conditions (i.e., when river stages and water tables are
higher than reported values) would be greater, and actual saturated CCR
volumes could be higher than estimated if portions of the unit with
lower documented waste bottom elevations (less than 422 ft above MSL)
were considered. The estimates provided by EPA below and in the TSD
Volume I are reasonable based on the available information provided in
the Permit Application regarding the waste bottom elevations.
ii. Characterization of Groundwater Elevations
    Information from TVA's Permit Application clearly supports a
conclusion that at least some portion of the CCR in Ash Pond 4 remains
saturated by continued infiltration of groundwater. The groundwater
elevation maps for 2020 and 2021 provided in the Permit Application
reveal that the lowest measured groundwater elevations range between
just over 414 to just over 416 ft above MSL.\24\ These levels are found
in groundwater monitoring wells COF-105 and CA31A, which are screened
in the residuum/alluvium layer, and consistently measure the lowest
groundwater elevations of any of the wells immediately surrounding Ash
Pond 4. In every measurement reported in the Permit Application, the
groundwater elevations measured in these wells are 0.86 to 2.7 feet
above the lowest documented elevation of CCR within the unit (413.5 ft
above MSL). Furthermore, COF-105 is located approximately 150 feet east
of the unit boundary in the downgradient direction and CA31A is located
approximately 400 feet northeast of the unit boundary in the
downgradient direction. As corroborated by monitoring well and
piezometer data from within the unit, the actual groundwater elevations
directly beneath the unit are generally higher than these minimum
recorded values, which are well beyond the unit boundary in
downgradient directions. This basic information clearly supports a
conclusion that at least some portion of the waste in Ash Pond 4 is wet
under typical conditions.
---------------------------------------------------------------------------

    \24\ Tennessee Valley Authority. Permit Application for CCR
Surface Impoundment, TVA Colbert Fossil Plant Ash Disposal Area 4.
December 10, 2021. Attachment H, Appendix A, Figures A-1 through A-
4.
---------------------------------------------------------------------------

    A closer examination of available data from the Permit Application
further supports this conclusion. Assuming that the base of the CCR is
uniformly at 422 ft above MSL, based on the contour intervals depicted
on the groundwater elevation map for February 27, 2020 (Figure A-1),
groundwater elevations range from 414.36 to 437.46 ft above MSL, and
exceed 422 ft above MSL at over fifty percent of the entire Ash Pond 4
footprint. Similarly, the groundwater elevation contours depicting the
February 22, 2021 (Figure A-3), groundwater elevation data documents
water levels ranging from 415.14 to 436.54 ft above MSL, indicating
that water levels greater than 422 ft above MSL are present at one-
third or more of the area within the impoundment.
    Even though data from summer monitoring events show that summer
groundwater levels are considerably lower than the data reported for
February 2020 and 2021, there still appears to be a considerable
footprint of wet waste under all reported conditions, and conditions
indicative of groundwater saturation or infiltration into the closed
unit appear to be sustained without interruption in some regions of the
unit. On August 10, 2020 (Figure A-2), groundwater levels ranged from
414.38 to 422.58 ft above MSL and are mapped between 415 and 420 ft
over most of the unit's footprint, with a small portion in the extreme
southwest corner of the mapped area showing higher groundwater levels
of greater than 420 ft. On August 23, 2021 (Figure A-4), groundwater
elevations ranged from 414.79 to 429.00 ft above MSL and are mapped as
being greater than 422 ft above MSL beneath a somewhat larger portion
of the impoundment's surface area in the southwestern corner, with the
remainder of groundwater elevations in the unit mapped between 415 and
420 ft above MSL.
    The Permit Application also presents groundwater elevation contour
maps for the Tuscumbia limestone bedrock aquifer for 2020 and 2021.
This is appropriate as there is an abundance of information contained
in the materials presented for the Permit Application, the annual
groundwater monitoring reports, and the 2019 Comprehensive Groundwater
Investigation Report that indicates that the Tuscumbia limestone
aquifer is in direct contact and is in direct hydraulic communication
with the overlying residuum/alluvium aquifer.\25\ In this respect, EPA
interprets the Tuscumbia limestone aquifer to be part of the uppermost
aquifer system for the unit. EPA's analysis in this regard is included
in Section II.b of the TSD Volume I.
---------------------------------------------------------------------------

    \25\ Stantec, Comprehensive Groundwater Investigation Report,
First Amended Consent Decree # 20-01-2013-900123 Ash Pond 4 and Ash
Stack 5. TVA Colbert Fossil Plant, Prepared for Tennessee Valley
Authority Chattanooga, Tennessee. May 17, 2019.
---------------------------------------------------------------------------

    For the Tuscumbia limestone, the Permit Application included four
contour maps from groundwater elevation measurement events on February
27, 2020, August 10, 2020, February 22, 2021, and August 23, 2021.\26\
These data sets, which are summarized in Table I below, generally
indicate that water levels in the bedrock aquifer are higher than the
422-foot base elevation beneath significant regions of the Ash Pond 4
footprint during most of these four monitoring events, particularly
during winter conditions. For February 27, 2020 (Figure A-5),
groundwater elevations in the Tuscumbia limestone ranged from 414.61 to
437.77 ft above MSL.\27\ TVA's interpretive contours depicting the
Tuscumbia limestone bedrock groundwater elevations for February 27,
2020, indicate that the entire

impoundment is characterized by water levels greater than or equal to
422 ft above MSL, except for a very small area near monitoring well
COF-111 near the eastern boundary. For February 22, 2021 (Figure A-7),
measured groundwater elevation data for the Tuscumbia limestone aquifer
ranged from 411.11 to 436.70 ft above MSL. TVA's interpretive contour
map for the same period indicates that groundwater levels at or above
422 ft above MSL were mapped at approximately half of the unit's
footprint. Similarly, on August 23, 2021 (Figure A-8), groundwater
elevation data ranged from 413.47 to 429.07 ft above MSL and
interpretive contours for same period for the Tuscumbia limestone
bedrock aquifer again indicate that approximately 50 percent of the
unit's footprint exhibits groundwater levels at or above 422 ft above
MSL. Conditions during the August 10, 2020 (Figure A-6), monitoring
event show lower groundwater levels, with groundwater elevation values
for the Tuscumbia limestone aquifer ranging from 412.85 to 422.54 ft
above MSL. TVA's interpretive groundwater elevation contours for the
same period show groundwater elevations below 422 ft above MSL in all
areas except for a small portion near the southwestern corner of the
unit. It should also be noted that surface water levels associated with
the four monitoring events listed above indicate that surface water
levels in the Pickwick Reservoir are greater than 413.5 ft above MSL
(the lowest documented waste bottom elevation) for two of the four
monitoring events as shown in Table I. It is also worth noting that
river stage, which fluctuates, was measured as above the lowest
groundwater elevations measured in the Tuscumbia limestone for three of
the four time periods presented in the Permit Application.
---------------------------------------------------------------------------

    \26\ Permit Application at Figures A-5 through A-8,
respectively.
    \27\ The elevation corresponding to wells CA29BR and CA22B on
Figures A-5 through A-8 were excluded from this range based on TVA's
footnote indicating these wells are ``poorly connected to site wide
groundwater flow system.''
---------------------------------------------------------------------------

    Together with the documented occurrence of solution features in the
limestone and associated preferential pathways in groundwater, it is
reasonable to expect some degree of hydraulic communication between the
reservoir/river and the underlying limestone aquifer. Depending on the
magnitude and duration of the occurrence of higher river/reservoir
levels, some degree of recharge from the river to the underlying
aquifers may be expected. It is perhaps partly for this reason that the
CCR in the unit remains wet, at least intermittently, so many years
after the unit was closed. Despite the disclaimer,\28\ which appears on
all the Tuscumbia groundwater elevation maps in the Permit Application,
EPA believes that the interpretive contours provided on these maps
corroborate the anisotropic groundwater flow conditions to which TVA
refers. EPA's interpretation of this information confirms the presence
of northeast striking preferential pathways within the Tuscumbia
limestone aquifer. In any event, the measured head values in the
Tuscumbia limestone aquifer within and surrounding the unit are hard
data points that enable the simplistic analysis regarding position of
the waste relative to measured water levels. EPA's analysis and
reasoning on this subject are further detailed in Section II.b of the
TSD Volume I.
---------------------------------------------------------------------------

    \28\ Permit Application at Note ``1'' on Figures A-5 through A-
8.

    Table I--Maximum and Minimum Reported Groundwater Elevations a for the Tuscumbia Limestone and Associated
     Contempraneous River Stage Elevations for Pickwick Reservoir on Four Monitoring Events During 2020-2021
----------------------------------------------------------------------------------------------------------------
                                                   Feb 27, 2020    Aug 10, 2020    Feb 22, 2021    Aug 23, 2021
----------------------------------------------------------------------------------------------------------------
High Groundwater Elevation......................          437.77          422.54           436.7          429.07
Low Groundwater Elevation.......................          414.61          412.85          411.11          413.47
River Stage \b\.................................          410.95          414.24          412.41          413.79
----------------------------------------------------------------------------------------------------------------
\a\ All data presented in feet above MSL, NGVD 29 datum.
\b\ River stage values obtained from Figures A-5 through A-8 in the Groundwater Plant in the Permit Application.

    The groundwater elevations provided in the Permit Application are
based primarily on data collected from outside of the unit, without
consideration of actual groundwater levels directly within and beneath
the unit. Although data from inside the unit were not provided in the
Permit Application, data from piezometers and monitoring points within
Ash Pond 4 are available in the Annual Inspection Reports posted on
TVA's CCR website. EPA reviewed the water level information reported in
the Annual Inspection Reports from 2016 through 2022.\29\ These reports
document the change of water levels within the unit over time since
closure and provide for a direct, more highly resolved and
representative analysis of actual groundwater levels and conditions
directly within and beneath the unit. These data demonstrate that
significant areas and volumes of CCR below the water table have been
and remain sustained within the unit as discussed in further detail
below. These data also enabled EPA to estimate the minimum volumes of
saturated CCR that remain in the closed unit under various observed
conditions.
---------------------------------------------------------------------------

    \29\ The TVA reports are titled: 2022 Engineering (Annual)
Inspection of CCR Facilities dated May 9, 2022; FY2021 Intermediate
Inspection of CCR Facilities dated May 6, 2021; FY2020 Intermediate
Inspection of CCR Facilities dated July 29, 2020; FY2019
Intermediate Inspection of CCR Facilities dated August 30, 2019;
FY2018 Intermediate Inspection of CCR Facilities dated September 4,
2018; and FY2017 Intermediate Inspection of CCR Facilities dated
December 15, 2017. Collectively, EPA is referring to one or more of
these reports as the ``Annual Inspection Reports.''
---------------------------------------------------------------------------

    The most recent Annual Inspection Report from May 2022 states that
``[t]here are 54 automated vibrating wire piezometers, eight (8)
automated slope inclinometers, and six (6) manual magnetic
extensometers installed at Ash Disposal Area 4.'' The Annual Inspection
Reports categorize the piezometers as ``A'' or ``B'' in the
alphanumeric identifiers assigned to each individual piezometer.
Because many of these ``A'' piezometers have recorded ``dry''
conditions in later monitoring events, it appears that the ``A'' series
piezometers generally represent the shallower portions of the
subsurface beneath the unit, e.g., screened primarily in CCR materials.
While there seems to be some degree of overlap in the vertical
dimension, the ``B'' series piezometers appear to be screened into
generally deeper stratigraphic intervals than the ``A'' series, and
generally reflect water levels in the deeper portions of the CCR waste
as well as the underlying native aquifer materials in contact with the
waste.
    The groundwater elevations measured in ``A'' and ``B'' series
piezometers for the post-closure period from 2019 through 2021 varied
over similar ranges. Groundwater elevations measured in the ``A''
series ranged from 414.58 to 447.4

ft above MSL during this post-closure period whereas groundwater
elevations in the ``B'' series ranged from 414.5 to 445.1 ft above MSL
during the same period. Average piezometric water levels in the shallow
``A'' piezometers during this post-closure period were generally at or
above 430 ft above MSL beneath most of the footprint of the unit,
except for a lobe of lower groundwater elevations (generally measured
from 423 to 428 ft above MSL or below) in the east-central portion of
the unit. The only groundwater elevations measured at or below 422 ft
above MSL were at locations on the extreme eastern edge of the
impoundment or further eastward in the vicinity of Cane Creek. At the
deeper ``B'' piezometers, average groundwater elevations during the
post-closure period from 2019 to 2021 were observed to be universally
greater than 425 ft above MSL except for a thin strip along the eastern
margin of the impoundment containing a small area (approximately 15% or
less of the unit's footprint area) of somewhat lower groundwater
elevations (ranging generally from 416 to 424 ft above MSL), which
projects into the unit in the vicinity of piezometer COF_P4_VWP03_B.
Lastly, the most recently reported groundwater elevation measurements
in each piezometer and well (in 2021) continue to show a similar
pattern, with nearly all groundwater elevation values between 425 to
440 ft above MSL, except for a thin strip of lower groundwater
elevations near the extreme eastern margin of the impoundment, again
with a small lobe-shaped area of lower groundwater elevations (421.5 to
424.2 ft above MSL) projecting a short distance into the central part
of the unit from the east-central edge. Again, groundwater exceeding
the average waste elevation of 422 ft above MSL was measured across
virtually the entire unit.\30\
---------------------------------------------------------------------------

    \30\ EPA's analysis of post-closure (2019-2021) groundwater
elevations within the unit evaluated ``A'' and ``B'' series
piezometers. It should be noted that the ``A'' series also included
a number of additional piezometers with an ``S'' designation
indicating shallow screened interval depths. Evaluation of ``A''
series data also included shallow alluvium monitoring wells COF-104,
-105, and -111, and CA-17A. Evaluation of ``B'' series data also
included alluvium monitoring wells COF-104, -105, and -111. It
should be noted that these monitoring wells are located along the
extreme eastern periphery of the unit or downgradient to the east of
the unit. It is also noted that these few monitoring wells
consistently recorded some of the lowest groundwater elevations in
the combined ``A'' and ``B'' data sets. In this this respect, the
average values for the ``A'' and ``B'' piezometers are somewhat
lower than they would be if the monitoring well data were excluded.
This is to say that actual average groundwater elevation conditions
within the unit proper are likely slightly higher than these
assessments reflect due to the inclusion of the monitoring well
data.
---------------------------------------------------------------------------

    EPA also evaluated these data using common commercially available
software for contouring groundwater data,\31\ creating a series of maps
that present a series of potentiometric surfaces and groundwater
elevation measurements based on monitoring well and piezometer data
from within Ash Pond 4, for various time frames and representative
values, including pre-closure, during or immediately after closure, and
post-closure. These groundwater elevation contour maps are available in
Section II.b of the TSD Volume I.
---------------------------------------------------------------------------

    \31\ EPA used EnviroInsite software to visualize geotechnical
data (e.g., contouring groundwater elevation data from discrete
point measurements).
---------------------------------------------------------------------------

    While different software packages could be used to contour
groundwater data and many different interpolation methods, EPA's
contouring approach honors the data and other known constraints and is
a conservate estimation of site conditions on those dates. These
computer-generated contour maps are useful to illustrate what the
measured groundwater elevations reveal: that groundwater levels
decreased immediately after closure, but even several years later
groundwater levels continue to exceed not only the lowest documented
waste bottom elevation (413.5 ft above MSL), but also the average waste
bottom elevation (422 ft above MSL) of the CCR in the unit. The
computer-generated contours of average groundwater elevations
representing pre-closure conditions measured at monitoring wells from
January 1, 2016, through December 31, 2017, indicate pronounced
groundwater mounding centered on the central and southcentral portions
of the unit where a broad region of groundwater elevations on the order
of 450 ft above MSL are outlined. See Section II.b in TSD Volume I.
Contours of average groundwater elevations over a timeframe that
includes the initiation of unit closure, measured at monitoring wells
and piezometers from January 1, 2018, through December 31, 2019,
indicate a reduction in the groundwater elevations beneath the central
part of the unit to values on the order of 430 ft above MSL. A
significant reduction in groundwater elevations as compared to pre-
closure conditions is evident from these data. Id. Further decreases in
groundwater elevations are indicated from computer-generated contours
of average groundwater elevations measured at monitoring wells and
piezometers post-closure from January 1, 2020, through December 31,
2021. However, the magnitude of groundwater elevation decreases is much
smaller compared to the period just after closure, with the
northeastern corner of the unit indicating the greatest relative
decrease. Id. It is important to note that despite the post-closure
decreases in groundwater elevations, groundwater levels currently
remain well above the lowest recorded waste bottom elevation (413.5 ft
above MSL) of CCR in the unit as well as the average (422-ft above MSL)
waste bottom elevation of CCR at the preponderance of the impoundment.
    It is important to note, however, that the foregoing analyses are
somewhat skewed to the high side of the range of groundwater
fluctuation because the Annual Inspection Reports list the highest
recorded value for each location over the reported time interval
(approximately the previous year). It is possible that some portions of
the unit are above the water table during certain times of year or
under certain hydrologic conditions. Nevertheless, the available
reported data strongly suggests that there is a large and measurable
volume of persistent wet CCR present in the closed unit. With these
caveats, EPA's overall analysis of groundwater elevation data for Ash
Pond 4 is as follows.
    Prior to closure, there appears to have been significant
groundwater mounding beneath Ash Pond 4 that has slowly decreased since
pond closure. Such mounding resulted in substantially higher
groundwater levels directly beneath the impoundment that generally
decrease radially (as indicated by lower levels consistently measured
in the monitoring wells in the peripheral and downgradient portions of
the unit). As discussed above, it appears that the ``A'' piezometers
(assumed shallow) are screened within the CCR materials and are
measuring piezometric head beneath the impoundment area and the
(assumed) deeper ``B'' piezometers are sampling groundwater in the
native geologic materials and/or CCR near the base of CCR waste beneath
the impoundment. The reported groundwater elevations in both the ``A''
(shallow) and the ``B'' (deeper) piezometers indicate that groundwater
continues to infiltrate into the CCR in many portions of the closed
unit as noted in the paragraphs above. While the assumed deeper
piezometers (``B'' series) typically have water levels somewhat closer
to those observed in the monitoring wells peripheral to the unit, the
generally higher elevations in the shallow (``A'') piezometers versus
the deeper (``B'') piezometers indicates that a downward vertical
gradient likely

existed between the impoundment and the underlying geologic materials
prior to closure, that the general potential for downward vertical
hydraulic gradients has been sustained during and following closure,
and that it persists currently, many years after closure. A detailed
analysis of well/piezometer construction information, boring logs and
other data are needed to further confirm and assess persistence,
magnitude, and variability of downward vertical hydraulic gradients
from the unit to the underlying aquifers.
    Upgradient (west) groundwater elevations were consistently above
waste bottom elevations, whereas downgradient waste bottom elevations
were consistently near or above groundwater elevations. In a general
sense, Ash Pond 4 can be described as a quasi-wedge-shaped body with
higher elevations and generally thicker waste profiles on the west
side, sloping eastward where generally thinner waste profiles occur at
lower elevations to the east. While the groundwater table also
generally slopes from west to east, the groundwater elevation surface
(i.e., water table) does not fall to the level of the base of the waste
except in small portions of the eastern half of the unit, at best, and
at worst only near the extreme eastern margins of the unit. This
equates to a quasi-wedge-shaped body of saturated waste with generally
higher elevations and greatest thicknesses to the west, pinching out in
the eastward direction at the eastern margin of the unit.
    These data and analyses underscore the general concerns that absent
active engineering measures, which the permit approved by Alabama does
not require, groundwater will continue to infiltrate into and flow out
of Ash Pond 4 and the waste will remain wet for the foreseeable future.
iii. Volumes of Saturated CCR Estimates
    Based on the available information concerning the configuration of
the CCR waste mass, elevation and configuration of the surface defining
the interface between the CCR waste and underlying native geologic
materials, and the position of the water table under a variety of
conditions, EPA made a series of calculations to estimate the volume of
CCR in Ash Pond 4 that continues to be saturated with groundwater. In
all the estimates, the volume of saturated waste is generally estimated
to be the area within the impoundment where groundwater elevations
exceed the average bottom elevation of 422 ft above MSL, using computer
contouring software to create modeled contours of the groundwater
elevation surface within the unit. Under all scenarios considered,
substantial volumes of CCR remain saturated by continually infiltrating
groundwater. EPA's analyses and the resulting estimates can be found in
Section II.c of the TSD Volume I.
    EPA estimates that significant volumes of saturated CCR currently
remain in the closed unit, ranging from 346,183 to 914,774 CY of CCR.
EPA further estimates that approximately 13% to 35% of the total volume
of CCR in the unit remains in the groundwater, and that 75% to 97% of
the total unit surface area is underlain by saturated CCR. Finally, EPA
estimates that, on average, approximately 6 to 13 feet of the CCR
remains saturated with groundwater. See Table II below.
    Under this approach, EPA used a 2-ft contour interval to create
more granular digital models of the groundwater surface elevation.
Computer contouring software was further used to calculate the areas
contained between successive 2-ft contour lines and to calculate the
average groundwater elevation for that subregion. Saturated waste
thickness values were then calculated for each sub-area containing
groundwater elevations greater than 422-ft above MSL. Thickness values
were then multiplied by the respective areas computed for each sub-area
to obtain partial volumes of CCR in the aquifer. Total volumes of
saturated CCR were then computed by adding the partial volumes for each
sub-area.
    Using this approach, three separate estimates of volumes of
saturated CCR were calculated from average groundwater elevations
reported from overburden monitoring wells for the following time
periods:
     Spring 2019 (January 1, 2019, through May 31, 2019),
     Spring 2020 (January 1, 2020, through May 31, 2020), and
     Spring 2021 (January 1, 2021, through May 31, 2021).
    Table II summarizes the volumes and areas of saturated CCR
calculated for each of these time intervals.

        Table II--Depth, Surface Area, and Volume Estimates of Saturated CCR at Ash Pond 4 for 2019-2021
----------------------------------------------------------------------------------------------------------------
                   Estimates of saturated CCR                       Spring 2019     Spring 2020     Spring 2021
----------------------------------------------------------------------------------------------------------------
Total Surface Area of Unit (SY) \a\.............................         275,880         275,880         275,880
Total CCR Volume (CY) \b\.......................................       2,600,000       2,600,000       2,600,000
Average Thickness of Saturated CCR (ft).........................              13              13               6
Surface Area of Unit with CCR in Groundwater (SY)...............         263,907         267,657         204,302
Percentage of Unit Area with CCR in Groundwater (%).............              96              97              75
Volume Percentage of Saturated CCR (%)..........................              35              33              13
Volume of Saturated CCR (CY)....................................         914,774         858,445         346,183
----------------------------------------------------------------------------------------------------------------
\a\ Source: AECOM. Closure and Post-Closure Plan. October 12, 2016.
\b\ Source: CTI and Associates. FY2021 Intermediate Inspection of CCR Facilities. May 6, 2021.

    The 2019 and 2020 total estimates of saturated CCR for the unit
were similar, 914,774 and 858,445 CY, respectively. Total volume
estimates for 2021 were lower (346,183 CY) owing to lower average
groundwater elevations over that period as compared to 2019 and 2020.
It should be noted that daily precipitation amounts from publicly
available data indicate a greater level of rainfall in the proximity of
the unit in Spring 2020 as compared to 2021. Additionally, ambient
groundwater levels in monitoring wells outside of the impoundment were
generally higher in 2020 as compared to 2021. Lastly, there is a
greater number of monitoring points with reported water level data for
2020. It is therefore likely that variations in local precipitation
exert a strong and variable influence on groundwater elevations beneath
and in the vicinity of the unit, and therefore the lower levels in 2021
are not enough to support a conclusion that the unit will eventually
dry itself out. In any case, the supplemental analysis using the more
refined contour intervals is consistent with and within the upper and
lower bounds of previous estimates, further corroborating the overall
conclusion of sustained and ongoing presence of significant volumes of
CCR that continues to be infiltrated by groundwater from within the
unit. The magnitude of the estimates clearly

varies in response to fluctuations in groundwater levels beneath the
unit due to variation in annual precipitation and other factors,
including closure. However, despite some evidence that water levels
have declined somewhat since closure, the record supports a conclusion
that substantial volumes of CCR will continue to be perpetually
inundated by groundwater.
    Based on all these data EPA is proposing to determine that both the
Closure Plan approved by ADEM and incorporated into the permit, and the
closure itself (which ADEM also approved) are not consistent with the
requirements in Sec.  257.102(d). Neither the approved Closure Plan nor
any other document in the record for the permit accounts for the levels
of groundwater present in the unit prior to closure or describes any
engineering measures taken to meet each of the Federal CCR closure-in-
place performance standards in Sec.  257.102(d)(1) and (2) in light of
the groundwater present in the unit. Nor, based on the post-closure
groundwater elevation data from piezometer wells from 2019 to the
present, did the approved closure address the groundwater continuously
flowing into and out of the CCR, as required by the Federal
regulations.
    The Federal regulations require that ``prior to installing the
final cover system . . . [f]ree liquids must be eliminated by removing
liquid wastes or solidifying the remaining wastes and waste residues.''
40 CFR 257.102(d)(2). 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. As EPA has
previously explained, based on the regulatory terms, the structure, and
context in which the terms are employed, as well as the dictionary
definitions of ``liquid,'' and the fact that nothing in the regulatory
definition limits the source of the liquid, EPA considers groundwater
to be a liquid under the existing regulation.\32\ 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 runoff, or
groundwater that migrates into the impoundment.
---------------------------------------------------------------------------

    \32\ U.S. EPA. Denial of Alternative Closure Deadline for
General James M. Gavin Plant, Cheshire, Ohio. November 18, 2022. pp
14-42; 88 FR 31,982, 31,992-31,993 (May 18, 2023).
---------------------------------------------------------------------------

    TVA's Annual Inspection Reports from 2016 through 2018 show that
groundwater was infiltrating into Ash Pond 4. The average groundwater