[Federal Register Volume 88, Number 227 (Tuesday, November 28, 2023)]
[Proposed Rules]
[Pages 83065-83072]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-26123]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 268

[EPA-HQ-OLEM-2023-0372; FRL 11026-04-OLEM]


Department of Energy Hanford Mixed Radioactive Waste Land 
Disposal Restrictions Variance

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The United States Environmental Protection Agency (EPA) is 
proposing to grant a treatability variance from the Land Disposal 
Restrictions (LDR) treatment standards for the U.S. Department of 
Energy (DOE) for approximately 2,000 gallons of mixed low-activity 
waste from the Hanford Site in Washington State. The petitioner 
demonstrated that treatment of the waste to the specified standard is 
technically inappropriate, and the treatment variance is sufficient to 
minimize threats to human health and the environment posed by land 
disposal of the waste. If the variance is granted, the waste will be 
stabilized subject to specified conditions, and disposed at 
EnergySolutions in Clive, Utah and/or Waste Control Specialists in 
Andrews County, Texas. The variance would allow DOE, Washington, and 
EPA to

[[Page 83066]]

evaluate the regulatory pathways by which separation, pretreatment, 
stabilization, and offsite disposal could be implemented for other 
Hanford mixed low-activity waste.

DATES: Comments must be received on or before December 28, 2023.

ADDRESSES: You may send comments, identified by Docket ID No. EPA-HQ-
OLEM-2023-0372, 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 Docket, Mail Code 
28221T, 1200 Pennsylvania Avenue NW, Washington, DC 20460.
     Hand Delivery or Courier: 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: Bethany Russell, Waste 
Characterization Branch, Materials Recovery and Waste Management 
Division, Office of Resource Conservation and Recovery (5304P), 
Environmental Protection Agency, 1200 Pennsylvania Ave. NW, Washington, 
DC 20460; telephone number: 202-566-0823; email address: 
[email protected].

SUPPLEMENTARY INFORMATION:

I. Public Participation

A. Docket

    EPA has established a docket for this action under Docket ID No. 
EPA-HQ-OLEM-2023-0372. All documents in the docket are listed in the 
https://www.regulations.gov index. Publicly available docket materials 
are available either electronically at https://www.regulations.gov or 
in hard copy at the EPA Docket Center. The Public Reading Room for the 
docket is open from 8:30 a.m. to 4:30 p.m. Eastern, Monday through 
Friday, excluding holidays. The telephone number for the Public Reading 
Room and Docket Center is (202) 566-1744.

B. Written Comments

    Submit your comments, identified by Docket ID No. EPA-HQ-OLEM-2023-
0372, 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. The EPA may 
publish any comment received to its public docket. Do not submit 
electronically any information you consider to be Confidential Business 
Information (CBI) or other information whose disclosure is restricted 
by statute. Multimedia submissions (audio, video, etc.) must be 
accompanied by a written comment. The written comment is considered the 
official comment and should include discussion of all points you wish 
to make. The EPA will generally not consider comments or comment 
contents located outside of the primary submission (i.e. on the web, 
cloud, or other file sharing system). For additional submission 
methods, the full EPA public comment policy, information about CBI or 
multimedia submissions, and general guidance on making effective 
comments, please visit https://www.epa.gov/dockets/commenting-epa-dockets.

C. Submitting CBI

    Do not submit information that you consider to be CBI 
electronically through https://www.regulations.gov or email. Send or 
deliver information identified as CBI to only the following address: 
ORCR Document Control Officer, Mail Code 5305-P, Environmental 
Protection Agency, 1200 Pennsylvania Avenue NW, Washington, DC 20460; 
Attn: Docket ID No. EPA-HQ-OLEM-2023-0372.
    Clearly mark the part or all of the information that you claim to 
be CBI. For CBI information in a disk or CD-ROM that you mail to EPA, 
mark the outside of the disk or CD-ROM as CBI and then identify 
electronically within the disk or CD-ROM the specific information that 
is claimed as CBI. In addition to one complete version of the comment 
that includes information claimed as CBI, a copy of the comment that 
does not contain the information claimed as CBI must be submitted for 
inclusion in the public docket. If you submit a CD-ROM or disk that 
does not contain CBI, mark the outside of the disk or CD-ROM clearly 
that it does not contain CBI. Information marked as CBI will not be 
disclosed except in accordance with procedures set forth in 40 Code of 
Federal Regulations (CFR) Part 2.

II. General Information

A. Does this document apply to me?

    This action applies only to DOE's Hanford facility located in 
Richland, Washington.

B. What action is the Agency taking?

    On August 2, 2023, the EPA received a petition from the DOE 
requesting a variance from a treatment standard of the LDR of 40 CFR 
268.40 for disposal of approximately 2,000 gallons of hazardous wastes 
generated from DOE's Test Bed Initiative (TBI). This document proposes 
to grant DOE's petition for a variance pursuant to 40 CFR 268.44.

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

    Sections 3004(d) through (g) of the Resource Conservation and 
Recovery Act (RCRA), 42 U.S.C. 6294(d)-(g), prohibit the land disposal 
of hazardous wastes unless such wastes meet the LDR treatment standards 
(or treatment standards) established by EPA (or the Agency). Section 
3004(m) of RCRA, 42 U.S.C. 6924(m), requires EPA to set levels or 
methods of treatment, if any, which substantially diminish the toxicity 
of the waste or substantially reduce the likelihood of migration of 
hazardous constituents from the waste so that short-term and long-term 
threats to human health and the environment are minimized. EPA has 
established treatment standards for all hazardous wastes.
    However, when facilities generate hazardous wastes which cannot be 
treated to the specified levels, or when it is technically 
inappropriate for such wastes to undergo the prescribed treatment, they 
can apply for a variance from a treatment standard.\1\ The requirements 
for a treatment variance are found at 40 CFR 268.44. An applicant for a 
treatment variance may demonstrate that it is inappropriate to require 
a waste to be treated to the level or by the method specified as the 
treatment standard, even though such treatment is technically possible. 
This is the criterion pertinent to today's action.\2\ The petitioner 
must also

[[Page 83067]]

demonstrate that compliance with any given treatment variance is 
sufficient to minimize threats to human health and the environment 
posed by land disposal of the waste.
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    \1\ See 51 FR at 40605-40606 (November 7, 1986); see also 62 FR 
64504 (December 5, 1997).
    \2\ According to 42 CFR 268.44(a)(2), a petitioner may obtain a 
variance from an applicable treatment standard if it is 
inappropriate to require the waste to be treated to the level 
specified in the treatment standard or by the method specified as 
the treatment standard, even though such treatment is technically 
possible. To show that this is the case, as applicable here, the 
petitioner must demonstrate that treatment to the specified level or 
by the specified method is technically inappropriate (for example, 
resulting in combustion of large amounts of mildly contaminated 
environmental media). Section 268.44(m) further requires the 
petitioner to demonstrate that compliance with any given treatment 
variance is sufficient to minimize threats to human health and the 
environment posed by land disposal of the waste.
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III. Background

A. Hanford Waste Description

    Nearly 56 million gallons of radioactive and hazardous waste (mixed 
waste) were generated from the Hanford Site's role in our nation's 
defense program during the Manhattan Project and the Cold War.\3\ A 
total of 149 single shell tanks (SSTs) were constructed and entered 
service at Hanford between the 1940s and 1960s to contain this waste. 
Beginning in the 1960s, an additional 28 double shell tanks (DSTs) were 
also constructed at Hanford. DST capacity is crucial for retrieval of 
SST waste. Between the 1940s and the mid-1980s, approximately 240,000 
tons of hazardous chemicals were added to Hanford's tanks.\4\
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    \3\ See Hanford Test Bed Initiative Fact Sheet, July, 2018, 
https://www.energy.gov/sites/prod/files/2018/07/f53/Hanford%20Test%20Bed%20Initiative%20Fact%20Sheet%207-12-18.pdf.
    \4\ Government Accountability Office, GAO 22-104365, Nuclear 
Waste Disposal: Actions Needed to Enable DOE Decision That Could 
Save Tens of Billions of Dollars (2021), at 7.
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    DOE regulates certain radioactive materials, including the 
radioactive portion of mixed waste at Hanford, pursuant to its self-
regulating authority under the Atomic Energy Act of 1954 (AEA), 42 
U.S.C. 2011, et seq. The Washington State Department of Ecology (ECY) 
regulates the hazardous portion of the mixed waste as dangerous waste 
pursuant to the Revised Code of Washington (RCW) Chapter 70A.300 and 
Washington Administrative Code (WAC) Chapter 173-303, as a State 
authorized to implement a hazardous waste program under the Resource 
Conservation and Recovery Act (RCRA).
    Under RCRA and RCRA-authorized Washington regulations, mixed wastes 
are generally subject to the treatment standards in 40 CFR 268.40. 
Where there is no specific treatment standard set forth for a mixed 
waste, the standard applicable to the hazardous waste code applies to 
the mixed waste. For certain mixed wastes, specific treatment standards 
have been established. Treatment by high-level vitrification (HLVIT) 
applies to the subcategory of radioactive high-level mixed wastes 
generated during the reprocessing of fuel rods and bearing the waste 
codes D002 and/or D004 through D011.\5\ EPA selected vitrification as 
the Best Demonstrated Available Technology (BDAT) for this waste, and 
established HLVIT as the treatment standard, in part because 
stabilization would not provide treatment of the high-level radioactive 
portion of the waste, and because the potential health hazards 
associated with exposure to radioactivity during analysis of this high-
level mixed waste precluded setting a concentration-based treatment 
standard.\6\
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    \5\ See WAC 173-303-140, which incorporates by reference 40 CFR 
268 at WAC 173-303-140(2)(a).
    \6\ 55 FR 22520, 22627 (June 1, 1990).
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B. Description of the Proposed Treatment and Disposal

    In 2013, DOE updated its decision to separate tank wastes with low 
levels of long-lived radionuclides (referred to as low-activity waste 
or LAW) from other tank waste, and to vitrify some of the LAW at 
Hanford's Tank Waste Treatment and Immobilization Plant (WTP). The 
vitrified waste form will be disposed of onsite at Hanford's Integrated 
Disposal Facility (IDF). The WTP has the design capacity to treat only 
around 60 percent of the LAW from the Hanford tanks.\7\ For the 
remaining LAW, DOE did not select a treatment method and found it would 
be ``beneficial to study further the potential cost, safety, and 
environmental performance of supplemental treatment technologies.'' \8\ 
DOE therefore proposed the TBI Demonstration.
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    \7\ See GAO 22-104365, Actions Needed to Enable DOE Decision 
That Could Save Tens of Billions of Dollars (2021), at 2.
    \8\ See 78 FR 75916.
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    DOE describes the TBI Demonstration as: (1) the onsite separation 
and pretreatment of supernate from Tank SY-101, located in the 200 West 
Area on the Central Plateau of the Hanford Site to remove the bulk of 
the key radionuclides from the supernate; (2) transport of the 
pretreated liquid waste to an offsite treatment facility for treatment 
using stabilization/solidification (grouting); and (3) disposal of the 
grouted waste form at a commercial disposal facility outside the State 
of Washington. Effectuating the TBI Demonstration would allow DOE, 
Washington, and EPA to evaluate the regulatory pathways by which 
separation, pretreatment, stabilization (grouting), and offsite 
disposal could be implemented for other Hanford mixed low-activity 
waste. Concurrently, DOE is applying for a Research Development & 
Demonstration (RD&D) Permit from ECY to perform the onsite pretreatment 
activities associated with the TBI Demonstration.\9\
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    \9\ U.S. Department of Energy, ORP-67633, 2,000-Gallon Test Bed 
Initiative Demonstration Research, Development, and Demonstration 
Permit Application, Revision. 0 (June 8, 2023) (hereinafter, RD&D 
Permit Application).
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    On August 2, 2023, DOE submitted to EPA a petition for a treatment 
variance under 40 CFR 268.44(a)(2) to implement the TBI Demonstration 
by treating approximately 2,000 gallons of supernate from Tank SY-
101.\10\ DOE selected Tank SY-101 for the TBI because of, among other 
reasons, the tank waste chemistry, including low organic 
concentration.\11\ Separation and pretreatment would involve filtration 
of solids, and use of a crystalline silicotitanate ion exchange media 
to capture and remove key radionuclides (including cesium (Cs-137) and 
daughter barium (Ba-137m) and strontium (Sr-90)) from the supernate. 
Tank SY-101 consists of two layers: the supernate, which comprises 
approximately 81 percent of the tank volume, and an undissolved salt 
cake layer beneath the supernate.
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    \10\ U.S. Department of Energy, 23-TF-0023, Test Bed Initiative 
Land Disposal Restrictions Variance Petition (August 1, 2023).
    \11\ U.S. Department of Energy, Test Bed Initiative at Hanford, 
Report to Congress (April 2019), at 7.
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    As requested in the petition and provided in this proposal, the 
pretreated supernate would be subject to a stabilization treatment 
method, hereafter referred to as STABL, with verification sampling to 
ensure the treated waste meets the numerical LDR treatment standards 
applicable to the waste codes provided in this proposal. The offsite 
commercial treatment facilities identified in the petition, 
EnergySolutions and Waste Control Specialists, would be required to 
conduct the stabilization treatment in compliance with their RCRA 
permits, as well as their radioactive material licenses.
    DOE anticipates that half of the pretreated liquid would be 
transported to EnergySolutions for grouting and disposal at its 
commercial facility in Clive, Utah, and half would be transported to 
Waste Control Specialists for grouting and disposal at its Federal 
Waste Facility (FWF) in Andrews County, Texas.\12\ The process totes 
used to transport the pretreated liquid waste offsite to 
EnergySolutions and Waste Control Specialists for treatment would meet 
all applicable U.S. Department of

[[Page 83068]]

Transportation (USDOT) requirements under 49 CFR Subchapter C.
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    \12\ See U.S. Department of Energy, Memorandum: Approval of 
Exemption of Use of Non-U.S. Department of Energy Facilities for the 
2,000-Gallon Test Bed Initiative Demonstration (June 8, 2023).
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    In accordance with DOE Order 435.1 Chg 2(AdminChg), Radioactive 
Waste Management and DOE Manual 435.1-1 Chg 3(LtdChg), Radioactive 
Waste Management Manual, DOE completed a Waste Incidental to 
Reprocessing (WIR) Evaluation for the 2,000-gallon TBI Demonstration in 
March 2023.\13\ Based on the WIR Evaluation, DOE determined that the 
separated, pretreated, and solidified supernate from Tank SY-101 is 
waste incidental to the reprocessing of spent nuclear fuel, is not 
high-level waste, and can be managed as a low-level waste.\14\
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    \13\ U.S. Department of Energy, DOE/ORP-2022-02, Revision 0, 
Final Waste Incidental to Reprocessing Evaluation for the Test Bed 
Initiative Demonstration (hereinafter, Final WIR Evaluation) (March 
2023); see 88 FR 16615 (March 20, 2023). https://www.hanford.gov/files.cfm/WIR_%E2%80%93_Final_WIR_Evaluation_for_the_TBI1.pdf.
    \14\ WIR Determination.
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    DOE also completed a Final Environmental Assessment (Final EA) for 
the 2,000-gallon TBI Demonstration in accordance with the National 
Environmental Policy Act (NEPA), and DOE's NEPA implementation 
regulations, 10 CFR part 1021.\15\ In the Final EA, DOE analyzed the 
environmental impacts associated with four combinations of facilities 
for grouting and disposal of the pretreated 2,000 gallons of supernate 
from Tank SY-101. The EA evaluated potential impacts of the TBI 
Demonstration to air quality, human health (both from normal operations 
and accidents or destructive acts), waste management, and 
transportation. Any proposal to separate, pretreat, stabilize, and 
dispose of any tank waste other than the TBI supernate from Tank SY-101 
would be evaluated in a separate NEPA review. DOE sent the draft EA 
with a request for input to host States and Tribes as well as States 
and Tribes that could be affected by the proposed action, as documented 
in Section 4 of the EA.\16\ DOE determined that the four alternatives 
analyzed for grouting and disposal will not constitute a major Federal 
action significantly affecting the quality of the human environment 
within the meaning of NEPA, and therefore issued a Finding of No 
Significant Impact (FONSI) on March 16, 2023.\17\
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    \15\ U.S. Department of Energy, Final Environmental Assessment 
of the Test Bed Initiative Demonstration, DOE/EA-2086 (March 2023). 
https://www.energy.gov/sites/default/files/2023-03/ea-2086-test-bed-initiative-hanford-2023-03_0.pdf.
    \16\ The following tribes and State agencies were notified of 
the preparation of the EA: Confederated Tribes of the Umatilla 
Indian Reservation, Nez Perce Tribe, Yakama Nation Tribe, Wanapum 
Tribe, Tennessee Department of Environment and Conservation, Texas 
Commission on Environmental Quality, State of Utah Public Lands 
Policy Coordination Office, Oregon State Department of Energy, 
Washington State Department of Ecology.
    \17\ Finding of No Significant Impact Test Bed Initiative 
Demonstration Hanford Site, Washington, DOE/EA-2086 (March 16, 
2023). https://www.hanford.gov/files.cfm/Final_--_230316_-_NEPA_FONSI_for_TBI_(Digital).pdf.
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IV. Basis for EPA's Proposed Determination

A. EPA's Approach to This Proposed Variance

    The regulatory framework and associated requirements of the RCRA 
LDR standards must be addressed to implement the 2,000-gallon TBI 
Demonstration and dispose of the grouted waste form at EnergySolutions 
in Clive, Utah, and/or Waste Control Specialists in Andrews County, 
Texas. As mentioned above, the LDR standard under RCRA and RCRA-
authorized Washington regulations for the subcategory of radioactive 
high-level mixed wastes generated during the reprocessing of fuel rods 
and bearing the waste codes D002 and/or D004 through D011 is HLVIT. DOE 
asserts that after Tank SY-101 supernate is processed through TBI, 
including separation of high- and low-activity waste fractions, 
pretreatment, and solidification, following a re-classification through 
a WIR determination, the solidified low-activity waste fraction can be 
managed and disposed as low-level radioactive waste. Once those steps 
are completed, DOE believes the HLVIT treatment standard does not apply 
and thus the separated, pretreated mixed waste would not be required to 
be vitrified. Washington interprets its RCRA-authorized LDR 
requirements such that the waste designation and all associated LDR 
treatment standards, including HLVIT, have already attached to the tank 
waste and remain attached to the separated, pretreated low-activity 
fraction of the tank waste until satisfied. Thus, according to 
Washington, if the waste is not vitrified, the HLVIT standard would 
need to be removed through some regulatory vehicle, such as a treatment 
variance, in order for that waste to be grouted instead of 
vitrified.\18\
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    \18\ For Washington's statements describing its position, see 
FFRDC Report 2023, Volume II p. 494-495.
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    EPA's decision to propose this treatment variance approval does not 
resolve DOE and the State's differing interpretations of the LDR 
requirements, and EPA is not concluding that HLVIT does or does not 
apply to the TBI waste. Rather, EPA proposes to approve this variance 
to provide a clear regulatory pathway for the 2,000-gallon TBI to 
proceed. As documented in a 2021 report by the General Accountability 
Office,\19\ DOE, Washington, and EPA agree that the TBI should proceed, 
to test the viability of a grouting approach to some of the Hanford 
tank waste. However, the regulatory disagreement between DOE and 
Washington remains unresolved. In view of this background--and the 
importance DOE, Washington and EPA all attach to making progress on the 
Hanford tank waste mission--EPA proposes to approve a variance clearly 
allowing the TBI to proceed, on the specific terms and subject to the 
specific conditions proposed today, regardless of whose interpretation 
forms the starting point for the variance analysis.
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    \19\ GAO-22-104365.
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    Specifically, EPA proposes to subject the TBI waste to a STABL 
(stabilization) treatment method, with verification sampling to ensure 
the treated waste meets the LDR numerical standards, as applicable, for 
waste codes F001-F005 (limited to constituents associated with spent 
solvent activities at the Hanford facility); D001-D011, D018, D019, 
D022, D028-D030, D033-D036, D038-D041, and D043. The waste codes 
included herein are those identified on the Dangerous Waste Permit 
Application Part A form for the DST System, Rev. 4 (December 14, 2009), 
which includes Tank SY-101.\20\ The codes include listed hazardous 
wastes bearing organic constituents, and toxic and corrosive 
characteristic wastes which ordinarily must meet concentration-based 
treatment standards under Washington's RCRA-authorized program. DOE's 
petition requests to use STABL to meet the numeric standard, therefore 
these wastes are included in this variance.
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    \20\ See Petition, Table 1. The data provided in Table 1 is 
derived from the Final Analytical Report for Tank 241-SY-101 TBI 
Grab Sampling 2018, RPP-RPT-61303 Rev. 05 (October 2020). All waste 
codes that appear on the DST System Part A form are included in this 
variance, with the exception of F039 (because the DST System has not 
accepted waste bearing that waste code). The sample result suggests 
that Tank SY-101 supernate displays only a limited subset of the 
waste codes listed on the DST System Part A form. See RD&D Permit 
Application, Sec. 4.1.2 and Table 4-1. DOE explains that Tank SY-101 
supernate does not exhibit the characteristics of ignitability 
(D001) and reactivity (D003) before or after pretreatment. 
Nonetheless, EPA understands that Washington views the SY-101 waste 
as bearing all of the codes on the Part A form (except for F039) and 
is therefore including the codes in the proposed variance, since the 
facility is regulated under Washington's authorized program. The 
inclusion of D001 and D003 does not affect the treatment required by 
the variance, since treatment for underlying hazardous 
characteristics for these waste codes is accounted for by the 
treatment required for the corrosivity (D002) and toxicity (D004-
043) characteristics.

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[[Page 83069]]

    Pursuant to 40 CFR 268.44(a)(2)(i), a variance may be approved if 
it is technically inappropriate to treat the waste to the level 
specified in the treatment standard, or by the method specified as the 
treatment standard, even though such treatment is technically possible. 
As with any section 268.44 treatment variance, the petitioner must also 
show that compliance with the variance will be sufficient to minimize 
threats to human health and the environment posed by land disposal of 
the waste.

B. Proposed Technically Inappropriate Determination

    In promulgating the Land Disposal Restrictions for Third Third 
Scheduled Wastes (Third Third Rule) that established the HLVIT 
treatment standard, EPA expressly recognized the effectiveness of 
grouting for immobilizing inorganic hazardous constituents in low-level 
mixed waste:

    The Agency believes that for treatment of metals in low-level 
mixed wastes and for some TRU mixed wastes containing low 
radioactive components, chemical precipitation will remove the 
metals in wastewaters, and stabilization technologies will reduce 
the leachability of the metal constituents in nonwastewater 
matrices. These are the same technologies that are applicable to 
nonradioactive wastes containing metals.
    DOE submitted data demonstrating the applicability of 
stabilization as a treatment technology for the low-level waste 
fractions that are separated from the high-level waste generated 
during the reprocessing of fuel rods. As used by one particular 
facility, a stabilization process called grout stabilization 
involves blending commercially produced cement-based reagents with 
the liquid low-level waste fraction. The material sets up as a solid 
mass, immobilizing the waste. The performance data indicate that 
stabilization provides immobilization of the characteristic metal 
constituents and radioactive contaminants for this low-level 
radioactive waste, and that it is possible to stabilize the RCRA 
hazardous portions to meet the treatment levels for the 
characteristic metals. . . .
    DOE provided information to support that vitrification is an 
applicable technology for their high-level wastes generated from the 
reprocessing of fuel rods. Treatment can be accomplished by using 
either direct vitrification or a more complex treatment process 
which includes a series of chemical steps that separate the low-
level radioactive waste fractions from the high-level radioactive 
waste. The high-level radioactive portion is then vitrified. When 
using separation technologies such as precipitation followed by 
settling or filtration, the bulk of the radioactivity can be 
incorporated into a high-level liquid waste containing up to 99 
percent of the radioactivity of the original irradiated fuel rods. 
By separating high-level and low-level mixed wastes, the amount of 
high-level waste that may require vitrification treatment can be 
reduced.

[55 FR 22626-2627 (June 1, 1990).]

    Tank SY-101 contains both inorganic and organic constituents; 
however, sampling results from Tank SY-101 supernate \21\ show that the 
organic constituents in the waste are at least one order of magnitude 
below the applicable nonwastewater (NWW) concentration-based LDR 
treatment standards except for 1-butanol (also referred to as n-Butyl 
alcohol).\22\ The sample results show that 1-butanol was not detected 
in the sample, however, the laboratory detection limit (2.78 mg/L) for 
this constituent is slightly above the NWW concentration-based standard 
(2.6 mg/kg). Thus, 1-butanol is either below or just slightly above 
this standard in the pre-treated waste, and EPA is confident that it 
will meet the LDR standard following treatment, and that grouting is an 
appropriate treatment technology for this constituent in this waste.
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    \21\ See Petition, Table 1.
    \22\ Because the final grouted waste form being disposed of will 
be a nonwastewater, the NWW standards are the relevant treatment 
standards for this proposed variance.
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    As referenced above, EPA expresses no opinion on whether the waste 
subject to this proposed variance must be vitrified under ECY's RCRA-
authorized LDR regulations. However, EPA believes that, under the facts 
and circumstances presented in DOE's petition for this waste stream and 
the terms of this proposed variance, it would be technically 
inappropriate to require the Tank SY-101 supernate to be treated by 
vitrification. As explained further below, in view of the efficacy of 
grout for immobilizing inorganic constituents, the fact that the 
organics concentrations in the pretreated liquid waste are below (or in 
the case of 1-butanol, below or just slightly above) the NWW standards, 
and the protective geologic features of the identified disposal sites, 
EPA believes that requiring Tank SY-101 supernate to be vitrified would 
be technically inappropriate. This is because vitrification would 
require more time to implement, result in additional secondary impacts, 
and be more costly--outcomes that EPA considers unnecessary and 
undesirable in view of its proposed determination that grouting under 
the terms of the proposed variance would minimize threats.
    The proposed approval applies only to the 2,000 gallons of 
separated, pretreated supernate from Tank SY-101. Therefore, these 
distinctions in impacts and outcomes between grouting and vitrifying 
the waste are small. That said, EPA believes they are tangible in 
proportion to the amount of waste involved, which is also small. 
Moreover, the TBI Demonstration is intended to test the viability of an 
approach involving grouting and offsite disposal for other low-activity 
waste from Hanford. Thus, the TBI could provide the basis for a broader 
approach under which these distinctions would be more significant.
    First, EPA believes grouting the waste, under the terms of the 
proposed variance, would speed up implementation of retrieval, 
treatment and disposal. In a peer-reviewed report issued in 2023, the 
Federally Funded Research and Development Center (FFRDC) recommended 
grouting and off-site disposal in parallel to vitrification due to the 
improved execution schedule and probability of successful project 
completion when compared to all other effective alternatives for waste 
beyond the capacity of the existing DFLAW.\23\ Tank SY-101 is not 
currently part of the direct-feed system for vitrification. To vitrify 
LAW from SY-101 would require construction of new infrastructure. Thus, 
the TBI would allow the 2,000 gallons of TBI waste to be retrieved, 
treated, and disposed of more quickly than would otherwise be possible. 
Conducting TBI in parallel to on-site vitrification of LAW from other 
tanks could provide multiple pathways for disposal of Hanford tank 
waste and provide the capability to achieve a more rapid reduction in 
the amount of waste stored, and therefore result in a more rapid 
reduction in risk to human health and the environment.\24\ Moreover, 
DST space in West Area is needed to allow for the receipt of waste 
retrievals from the aging SSTs for vitrification. In 2021 the 
Government Accountability Office (GAO) reported that insufficient tank 
space is the top risk to the Hanford cleanup mission, with a 95 percent 
chance of running out of DST space to continue retrieval of SST 
waste.\25\ The May 2017 GAO report, which discussed the potential 
reduction in short-term risks and long-term costs from treating a 
portion of LAW with grout, stated that grouting could reduce the 
environmental risk posed by leaks from aging tanks by removing waste 
from such tanks sooner than vitrification would. The availability of 
DST space, including in SY-101, is thus integral to DOE's cleanup 
mission at Hanford. Grouting the TBI waste would free up 2,000 gallons 
of DST space that could be

[[Page 83070]]

used for waste retrieved from SSTs, allowing for optimized retrieval 
sequencing to reduce environmental and human health risk more 
rapidly.\26\
---------------------------------------------------------------------------

    \23\ FFRDC Report 2023, Volume I page 52.
    \24\ See FFRDC Report 2023 page 52.
    \25\ GAO-21-73.
    \26\ See FFRDC 2023 page 52.
---------------------------------------------------------------------------

    Again, these distinctions as applied to the 2,000 gallons are 
small, but if the TBI demonstrates the effectiveness of a regulatory 
pathway for other Hanford low-activity waste via grouting and offsite 
disposal, that could substantially facilitate DOE's ability to meet its 
SST retrieval schedule and allow DOE to complete its cleanup mission in 
less time than it would if vitrification is required for all of 
Hanford's low-activity waste.\27\ Grouting could provide an alternative 
treatment pathway that would allow 200 West Area tanks to be retrieved, 
and supernate from those tanks to be treated and disposed of offsite, 
decades earlier than the baseline approach of vitrification. Given that 
these tanks are well past their design life and are at risk of leaking, 
this would help mitigate the environmental risk of this tank waste (and 
attendant costs) sooner.
---------------------------------------------------------------------------

    \27\ See GAO 22-104365, p. 44-45; GAO, GAO 21-73, Hanford 
Cleanup, DOE's Efforts to Close Tank Farms Would Benefit from 
Clearer Legal Authorities and Communication (January 2021). See, 
also, 2023 FFRDC Follow-On Report, Vol. 1, p. 9-11 (finding, for 
example, that every two years of WTP vitrification operations 
without LAW supplemental treatment adds one year to the overall 
mission).
---------------------------------------------------------------------------

    Second, vitrification of the 2,000 gallons of Tank SY-101 supernate 
would result in certain secondary impacts, which are unnecessary and 
avoidable under these circumstances given the efficacy of grouting, the 
protective geologic features of the identified disposal sites, and the 
terms of the proposed variance. When LAW is vitrified, the water 
present in LAW is not incorporated into the glass matrix as part of the 
treatment process. The water initially present in the LAW, as well as 
any water produced as part of the treatment process, must then be 
recycled back into the vitrification system or managed as a liquid 
secondary waste, which would contain low levels of radionuclides and 
hazardous constituents not otherwise immobilized or destroyed by the 
glass-forming step. In contrast, when pretreated LAW is grouted instead 
of vitrified, the water content of the waste is incorporated into the 
cementitious matrix.
    Vitrification also generates secondary waste streams (such as high-
efficiency particulate air filters, carbon adsorber beds, spent or 
failed melters, and melter components), whereas grouting generates 
minimal secondary wastes.\28\ Furthermore, vitrification is a high 
temperature process that generates offgas that requires management and 
treatment for worker and public protection, whereas grouting takes 
place at much lower temperatures and is less energy-intensive than 
vitrification.\29\
---------------------------------------------------------------------------

    \28\ See, 2023 FFRDC Follow-On Report, Vol. I, App. B.
    \29\ See, 2023 FFRDC Follow-On Report, Vol. I, p. 3-4.
---------------------------------------------------------------------------

    Vitrification of TBI tank waste would also be more costly than 
grouting to achieve near-term risk reduction. Additional vitrification 
capability would need to be constructed before the TBI waste and any 
other low-activity waste from Hanford's 200 West Area could be 
vitrified. Multiple independent sources estimate the costs of grouting 
and off-site disposal vs vitrification.\30\ For example, the 2023 FFRDC 
Follow-On Report states that grouting would minimize financial demands 
by reducing mission duration and lifecycle costs and indicates that 
grouting is clearly executable at benchmark funding levels.\31\ In 
light of this, EPA believes grouting and offsite disposal of TBI waste 
in accordance with the terms of this approval would be cheaper than 
vitrification. Cost savings can also be realized by reducing the amount 
of waste that needs to be managed in tanks. The GAO reported in 2021 
that DOE spent more than $400 million per year from 2017-2019 
maintaining the waste in the tanks.\32\ Finally, the reduction of waste 
quantity managed in aging tanks has the potential to reduce cleanups 
costs associated with waste leaking from the tanks.
---------------------------------------------------------------------------

    \30\ See 2019 FFRDC Report; 2022 GAO report; 2023 FFRDC Follow-
On Report.
    \31\ GAO-17-306
    \32\ GAO-21-73.
---------------------------------------------------------------------------

    EPA recognizes there are differences in reporting on how much time, 
cost, and secondary impacts would be reduced by grouting some of the 
Hanford low-activity waste rather than vitrifying it. However, EPA 
believes there would be savings under all three metrics.
    Finally, the characteristics of the two facilities that would be 
authorized for disposal of the grouted waste form under the proposed 
variance support EPA's proposed determination that requiring HLVIT 
would be technically inappropriate for the TBI waste as described 
below.
    First, these two facilities feature favorable physical, including 
geologic, features, as described in section II.C below.\33\ These 
features would help ensure that threats to human health and the 
environment posed by disposal of the grouted SY-101 supernate are 
minimized. EPA's proposed technical inappropriateness determination is 
dependent on its proposed threat minimization determination.
---------------------------------------------------------------------------

    \33\ The geology underlying the IDF differs from the geology 
underlying these two facilities in certain respects, see Section 
II.C page 14 below.
---------------------------------------------------------------------------

    Second, because the pre-treated LAW will still contain 
radionuclides, EPA notes that disposal must be in accordance with the 
Nuclear Regulatory Commission's (NRC) performance objectives at 10 CFR 
part 61, subpart C for disposal of LLW. The performance objective 
requirements for licensed MLLW disposal facilities in the Texas 
Administrative Code and the Utah Administrative Code mirror and are 
comparable to the NRC's performance objectives, as discussed in detail 
in the 2,000-gallon TBI Demonstration Final WIR Evaluation.\34\
---------------------------------------------------------------------------

    \34\ See Final WIR Evaluation, p. 4-2; 5-1.
---------------------------------------------------------------------------

    For all the reasons above, EPA concludes that requiring treatment 
by vitrification would be technically inappropriate for this 2,000 
gallons of Tank SY-101 supernate in view of the efficacy of grouting, 
the protective geologic features of the identified disposal sites, and 
the conditions specified in the proposed variance.

C. Proposed Minimization of Threat Determination

    EPA proposes to determine that grouting of the pre-treated, low 
activity fraction of the Tank SY-101 supernate, under the terms of the 
proposed variance, would minimize threats to human health and the 
environment posed by disposal of the waste. The proposed minimization 
of threat finding is predicated on the TBI waste being treated to the 
LDR standard of STABL, with verification through samples collected 
after grouting to demonstrate that the stabilization achieves the NWW 
LDR concentration-based and Toxicity Characteristic Leaching Procedure 
(TCLP)-based standards, as applicable, for F001-F005 (limited to 
constituents associated with spent solvent activities at the Facility); 
D001-D011, D018, D019, D022, D028-D030, D033-D036, D038-D041, and D043.
    The EPA-approved STABL treatment technology is described as 
``[s]tabilization with the following reagents (or waste reagents) or 
combinations of reagents: (1) Portland cement; or (2) lime/pozzolans 
(e.g., fly ash and cement kiln dust) . . .'' 40 CFR 268.42. This method 
includes the grouting technology that DOE requests approval for. As 
described above, EPA in the Third Third Rule preamble generally 
concluded that stabilization was an appropriate technology for low-
level waste fractions that are separated

[[Page 83071]]

from the high-level waste generated during the reprocessing of fuel 
rods. To comply with STABL, the offsite commercial treatment facilities 
would be required to use the appropriate stabilization methods that 
meet applicable regulatory requirements in accordance with the 
facilities' waste permits and radioactive material licenses, as 
applicable.
    Moreover, under the proposed variance, the grouted waste would be 
required to meet the numerical treatment standards applicable to the 
waste codes for the subject waste. While confirmation sampling would 
not typically be conducted for waste subject to the STABL standard, 
since it is a method-based standard, sampling after treatment at the 
offsite commercial treatment facilities would be conducted for the 
purpose of validating treatment performance against the NWW numerical 
standards at 268.40 and, as applicable, at 268.48.\35\ EPA determined 
in promulgating these numerical standards that they minimize threats 
posed by disposal of hazardous waste bearing the relevant waste codes, 
as required by RCRA section 3004(m).
---------------------------------------------------------------------------

    \35\ DOE has requested this confirmation sampling in the context 
of the 2,000-gallon TBI to support and inform the development of a 
possible method-based treatment standard for other Hanford tank 
waste. DOE indicates that it may submit a variance request in the 
future for other tank waste that may provide a basis to eliminate 
the need for post-treatment sampling. Today's proposal is limited to 
the 2,000-gallon TBI, and EPA expresses no view as to the 
appropriateness of proposals DOE may advance in the future for 
treatment of other Hanford tank waste.
---------------------------------------------------------------------------

    Based on the sampling data provided by DOE, EPA fully expects that 
the numerical treatment standards will be met. All metals other than 
chromium are below NWW TCLP standards based on their measured total 
concentrations in Tank SY-101. A previous grouting recipe used by DOE 
provided a retention factor for chromium which can be used to predict 
the TCLP concentrations found in the final grouted waste form. This 
demonstration showed that the chromium TCLP leachate concentration in 
the grouted waste form would be two to three orders of magnitude less 
than the NWW TCLP numerical standard.\36\ While this grout recipe may 
not be identical to the recipe used in this proposed action, grouting 
is generally BDAT for metal constituents and is therefore expected to 
immobilize the chromium and therefore minimize threats.\37\
---------------------------------------------------------------------------

    \36\ DOE details in their petition: In Tank SY-101 supernate, 
chromium was detected at 95.8 mg/L. Available data on chromium in 
relation to DOE's Cast Stone formulation indicate that the retention 
factor for chromium is between 3.3x10-5 and 1.3x10-4 (mg_Cr/
L_leachate)/(mg_Cr/kg_solid), which corresponds to an EPA SW-846 
Method 1311 TCLP concentration of between 9.9x10-4 and 3.9x10-3 
(mg_Cr/L_leachate). In contrast, the NWW treatment standard for 
chromium is 0.6 (mg_Cr/L_leachate). Thus, the TCLP leachate 
concentration for the grouted waste form is expected to be two or 
three orders of magnitude less than the NWW numerical standard.
    \37\ EPA 402-R-96-014, Stabilization/Solidification Processes 
for Mixed Waste, page 36.
---------------------------------------------------------------------------

    As described earlier, the organic wastes are already at least an 
order of magnitude below the NWW standards, except for 1-butanol, which 
below or just slightly above the treatment standard. For this reason, 
targeted organics destruction or removal in addition to grouting is not 
necessary to minimize threats to health and the environment.
    EPA's proposed determination is supported by independent 
assessments. For example, experts convened by the National Academies of 
Science in 2016 concluded that both vitrification and grout could 
effectively treat Hanford low activity waste and be protective of human 
health.\38\
---------------------------------------------------------------------------

    \38\ GAO-22-104365, Nuclear Waste Disposal: Actions Needed to 
Enable DOE Decision That Could Save Tens of Billions of Dollars, at 
50-51.
---------------------------------------------------------------------------

    Finally, the treatment and disposal facilities that would be 
authorized by this variance are particularly appropriate for this 
waste. Most importantly, the grouted waste form will be disposed of at 
EnergySolutions in Utah and/or Waste Control Specialists in Texas, both 
of which are commercial facilities that are RCRA-permitted and licensed 
by the applicable State authorities pursuant to their agreement with 
the NRC to accept mixed waste in accordance with their Waste Acceptance 
Criteria. Because the pre-treated LAW will still contain radionuclides, 
disposal must be in accordance with the NRC performance objectives at 
10 CFR part 61, subpart C for disposal of LLW. The performance 
objective requirements for licensed MLLW disposal facilities in the 
Texas Administrative Code and the Utah Administrative Code mirror and 
are comparable to the NRC's performance objectives, as discussed in 
detail in the 2,000-gallon TBI Demonstration Final WIR Evaluation. 
Those licensed facilities are subject to regulations and conditions 
that ensure the protection of public health and safety and the 
environment.
    The disposal facilities were also specifically selected based on 
their location, geology, hydrogeology, and experience in receiving 
comparable waste types for disposal. The EnergySolutions facility is 
located in a remote area of Utah with low-permeability clay soils 
immediately under the facility. Any potential for exposures via the 
groundwater pathway is further reduced due to naturally poor 
groundwater quality at the site which is extremely saline and exceeds 
EPA and Utah State drinking water standards for several naturally 
occuring constituents.\39\ No domestic water use occurs within 10 km of 
the facility.\40\ The precipitation levels in the area are low, 
evaporation is high, and the nearest stream channel is 2 miles east of 
the facility, thus minimizing the potential for releases via any 
surface water pathway.\41\ All of those characteristics make the site 
well-suited for the disposal of the TBI waste.
---------------------------------------------------------------------------

    \39\ 2023 FFRDC Follow-On Report, Vol. II, p. G-13.
    \40\ 2023 FFRDC Follow-On Report, Vol. II, p. G-18.
    \41\ 2023 FFRDC Follow-On Report, Vol. II, p. G-18.
---------------------------------------------------------------------------

    Similarly, the Waste Control Specialists FWF facility is in a 
physical setting that is naturally protective of human health and the 
environment. The area receives less than 16 inches of precipitation 
annually and evapotranspiration exceeds precipitation rates.\42\ There 
are no perennial streams on or near the site.\43\ The site sits on top 
of a 600-ft geologic layer of silts, muds and other low-permeability 
constituents.\44\ The first continuously saturated zone is 225 ft below 
ground surface and has extremely low permeability, retaining water from 
the Pleistocene era.\45\ The water volume is not sufficient to support 
an individual, and is non-potable.\46\
---------------------------------------------------------------------------

    \42\ 2023 FFRDC Follow-On Report, Vol. II, p. G-33.
    \43\ 2023 FFRDC Follow-On Report, Vol. II, p. G-33.
    \44\ 2023 FFRDC Follow-On Report, Vol. II, p. G-27.
    \45\ 2023 FFRDC Follow-On Report, Vol. II, p. G-31.
    \46\ 2023 FFRDC Follow-On Report, Vol. II, p. G-31.
---------------------------------------------------------------------------

    The geologic features, low infiltration, and no credible pathway to 
surface water or potable water aquifers at both EnergySolutions in Utah 
and Waste Control Specialists in Texas provide additional long-term 
environmental protections for waste that would help ensure that threats 
to human health and the environment posed by the disposal of the 
grouted SY-101 supernate are minimized.\47\ Conversely, with respect to 
geology, Hanford's IDF overlies unconsolidated to semi-consolidated 
sediments with no intervening natural barrier between the landfill and 
the underlying aquifer. However, EPA is not making a decision on 
whether a

[[Page 83072]]

variance would be appropriate for disposal in landfills other than 
those evaluated in the petition.
---------------------------------------------------------------------------

    \47\ 2023 FFRDC Follow-On Report, Vol. I, p. 52.

                                  Table 1--Proposed Modification to 40 CFR 268.44(o) for the TBI Demonstration Petition
                                            Wastes Excluded From The Treatment Standards Under Sec.   268.40
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                              Wastewaters                       Nonwastewaters
                                                                    Regulated    -----------------------------------------------------------------------
  Facility name and address      Waste code        See also         hazardous       Concentration                       Concentration
                                                                   constituent         (mg/L)             Notes            (mg/L)             Notes
--------------------------------------------------------------------------------------------------------------------------------------------------------
United States Department of   F001-F005 D001-  NA..............  For waste codes  NA..............  NA..............  STABL\19 20\....  NA.
 Energy (Energy), Richland,    D011, D018,                        F001-F005, the
 WA \17\.                      D019, D022,                        constituents
                               D028-D030,                         are limited to
                               D033-D036,                         those
                               D038-D041, and                     associated
                               D043 \18\.                         with spent
                                                                  solvent
                                                                  activities at
                                                                  the Facility
                                                                  documented
                                                                  through
                                                                  process
                                                                  knowledge.
                                                                 For
                                                                  constituents,
                                                                  as applicable,
                                                                  associated
                                                                  with D waste
                                                                  codes under
                                                                  the ``Waste
                                                                  Code'' column,
                                                                  see 40 CFR
                                                                  268.40.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\17\ The STABL treatment standard applies to the separated and pretreated tank waste under the 2,000-gallon TBI Demonstration.
\18\ The waste codes included in this column are those identified on the current version of the Dangerous Waste Permit Application Part A form for the
  Hanford Double Shell Tank System, Rev. 04 (December 14, 2009), except for F039 which has not been accepted into the Double Shell Tanks.
\19\ Sampling after treatment will be conducted at the treatment facility for the purpose of assessing the extent of treatment performance against the
  NWW numerical standards at 268.40 and, as applicable, at 268.48. Waste treated using STABL may not be land disposed until LDR constituents are below
  the non-wastewater numerical standards at 40 CFR 268.40 and 268.48.
\20\ Treatment using the STABL treatment method shall be performed, and the treated waste shall be disposed of, at EnergySolutions in Clive, Utah, and/
  or Waste Control Specialists in Andrews County, Texas.


Barry N. Breen,
Principal Deputy Assistant Administrator, Office of Land and Emergency 
Management.
[FR Doc. 2023-26123 Filed 11-27-23; 8:45 am]
BILLING CODE 6560-50-P