Document ID: EPA-HQ-OAR-2013-0684-0001
Agency: epa
Document Type: Proposed Rule
Title: Waste Isolation Pilot Plant Compliance with Disposal Regulations; Criteria for Certification and Recertifications: Panel Closure Redesign
Posted Date: 2013-12-03T05:00Z

[Federal Register Volume 78, Number 232 (Tuesday, December 3, 2013)]
[Proposed Rules]
[Pages 72612-72620]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-28240]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 194

[EPA-HQ-OAR-2013-0684; FRL-9903-38-OAR]

Criteria for the Certification and Recertification of the Waste 
Isolation Pilot Plant's Compliance With the Disposal Regulations; Panel 
Closure Redesign

AGENCY: Environmental Protection Agency.

ACTION: Proposed rule.

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SUMMARY: With this notice, the U.S. Environmental Protection Agency 
(EPA, or the Agency) proposes to approve the U.S. Department of 
Energy's (DOE, or the Department) planned change request to implement 
the Run-of-Mine Panel Closure System (ROMPCS) at the Waste Isolation 
Pilot Plant (WIPP) and to amend the WIPP Compliance Criteria to allow 
an EPA-approved panel closure other than the currently-required Option 
D design. Technical analyses demonstrate that, with the modified panel 
closure design, WIPP remains in compliance with the release limits set 
by the ``Environmental Standards for the Management and Disposal of 
Spent Nuclear Fuel, High-Level and Transuranic (TRU) Radioactive 
Waste.'' The proposed changes do not lessen the requirements for 
complying with the Compliance Criteria, nor do these changes impact the 
technical approach that the EPA will employ when considering any future 
planned changes to the panel closure system. Compliance with 
environmental or public health regulations other than the EPA's 
disposal regulations and WIPP Compliance Criteria is not addressed by 
today's action. Today's notice marks the beginning of a 60-day public 
comment period on this proposed action.

DATES: Comments must be received on or before February 3, 2014.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-
OAR-2013-0684, by one of the following methods--
     www.regulations.gov: Follow the on-line instructions for 
submitting comments.
     Email: to a-and-r-docket@epa.gov; Docket ID No. EPA-HQ-
OAR-2013-0684.
     Fax: (202) 566-1741.
     Mail: Air and Radiation Docket and Information Center, 
Environmental Protection Agency, Mail Code: 6102T, 1200 Pennsylvania 
Ave. NW., Washington, DC 20460.
    Instructions: Direct your comments to Attn: Docket ID No. EPA-HQ-
OAR-2013-0684. The Agency's policy is that all comments received will 
be included in the public docket without change and may be made 
available online at www.regulations.gov, including any personal 
information provided, unless the comment includes information claimed 
to be Confidential Business Information (CBI) or other information 
whose disclosure is restricted by statute. Do not submit information 
that you consider to be CBI or otherwise protected through 
www.regulations.gov or email. The www.regulations.gov Web site is an 
``anonymous access'' system, which means the EPA will not know your 
identity or contact information unless you provide it in the body of 
your comment. If you send an email comment directly to the EPA without 
going through www.regulations.gov, your email address will be 
automatically captured and included as part of the comment that is 
placed in the public docket and made available on the Internet. If you 
submit an electronic comment, the EPA recommends that you include your 
name and other contact information in the body of your comment and with 
any disk or CD-ROM you submit. If the EPA cannot read your comment due 
to technical difficulties and cannot contact you for clarification, the 
Agency may not be able to consider your comment. Electronic files 
should avoid the use of special characters or any form of encryption 
and be free of any defects or viruses. For additional information about 
the EPA's public docket, visit the EPA Docket Center homepage at http://www.epa.gov/epahome/dockets.htm.
    Docket: All documents in the docket are listed in the 
www.regulations.gov index. Although listed in the index, some 
information is not publicly available, e.g., CBI or other information 
whose disclosure is restricted by statute.

[[Page 72613]]

Certain other material, such as copyrighted material, will be publicly 
available only in hard copy. The EPA has established a docket for this 
action under Docket ID No. [EPA-HQ-OAR-2013-0684; FRL-9903-38-OAR]. 
Publicly available docket materials related to this action (e.g., the 
Technical Support document [TSD]) are available either electronically 
through www.regulations.gov, on the Agency's WIPP Web site (http://www.epa.gov/radiation/wipp) or in hard copy at the Air and Radiation 
Docket in the EPA Docket Center, (EPA/DC) EPA West, Room 3334, 1301 
Constitution Ave. NW., Washington, DC 20004. The EPA Docket Center 
Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through 
Friday, excluding legal holidays. The telephone number for the Public 
Reading Room is (202) 566-1744 and the telephone number for the Air and 
Radiation Docket is (202) 566-1742. In accordance with the EPA's 
regulations at 40 CFR part 2 and in accordance with normal EPA docket 
procedures, if copies of any docket materials are requested, a 
reasonable fee may be charged for photocopying.

FOR FURTHER INFORMATION CONTACT: Ray Lee or Jonathan Walsh, Radiation 
Protection Division, Mail Code 6608J, U.S. Environmental Protection 
Agency, 1200 Pennsylvania Avenue, Washington, DC 20460; telephone 
number: 202-343-9463 or 202-343-9238; fax number: 202-343-2305; email 
address: lee.raymond@epa.gov or walsh.jonathan@epa.gov.

SUPPLEMENTARY INFORMATION:

Preamble Acronyms and Abbreviations:

    Several acronyms and terms used to describe components of the WIPP 
disposal system and performance assessment computer models are included 
in this preamble. To ease the reading of this preamble and for 
reference purposes, the following terms are defined here:

BRAGFLO Computer model used to simulate brine and gas flow
CBFO Carlsbad Field Office
CCA Compliance Certification Application
CCDF Complementary Cumulative Distribution Function
CFR Code of Federal Regulations
DBR Direct Brine Release
DOE U.S. Department of Energy
DRZ Disturbed Rock Zone
EPA U.S. Environmental Protection Agency
FEPs Features, Events and Processes
LWA Land Withdrawal Act
MSHA Mine Safety and Health Administration
NMED New Mexico Environment Department
OPC Ordinary Portland Cement
PA Performance Assessment
PABC Performance Assessment Baseline Calculation
PAVT Performance Assessment Verification Test
PCS Panel Closure System
PCS-2012 Panel Closure System 2012 Performance Assessment
PCR Planned Change Request
PC3R Panel Closure Redesign and Repository Reconfiguration 
Performance Assessment
PMR Permit Modification Request
RCRA Resource Conservation and Recovery Act
ROM Run-of-Mine
ROMPC, or
ROMPCS6 Run-of-Mine Salt Panel Closure System
SMC Salado Mass Concrete
SNL Sandia National Laboratories
TRU Transuranic
TSD Technical Support Document
VOC Volatile Organic Compound
WIPP Waste Isolation Pilot Plant

Table of Contents

I. General Information
    A. What should I consider as I prepare my comments for the EPA?
II. What is the WIPP?
III. What is the purpose of today's proposed action?
IV. How is the EPA responding to the DOE's planned change request?
    A. What are the EPA's requirements for the panel closure design?
    B. What changes are proposed to the panel closure design?
    C. How has the EPA reached its decision?
V. How is the EPA revising Appendix A, Condition 1?
    A. What are the current requirements of Appendix A, Condition 1?
    B. What changes are proposed to Appendix A, Condition 1?
    C. What did the EPA consider when making its decision?
VI. How has the EPA involved the public?
VII. Administrative Requirements
    A. Executive Order 12866
    B. Regulatory Flexibility Act
    C. Paperwork Reduction Act
    D. Unfunded Mandates Reform Act
    E. Executive Order 12898
    F. National Technology Transfer & Advancement Act of 1995
    G. Executive Order 13045: Children's Health Protection
    H. Executive Order 13132: Federalism
    I. Executive Order 13175: Consultation and Coordination With 
Indian Tribal Governments
    J. Executive Order 13211: Energy Effects

I. General Information

A. What should I consider as I prepare my comments for the EPA?

1. Submitting Confidential Business Information (CBI):
    Do not submit this information to the EPA through 
www.regulations.gov or email. Clearly mark all of the information that 
you claim to be CBI. For CBI information in a disk or CD ROM that you 
mail to the 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. Information marked as CBI 
will not be disclosed except in accordance with procedures set forth in 
40 CFR part 2.
2. Tips for Preparing Your Comments:
    When submitting comments, remember to--
     Identify the rulemaking by docket number, subject heading, 
Federal Register date and page number.
     Follow directions--the EPA may ask you to respond to 
specific questions or organize comments by referencing the chapter 
number.
     Explain why you agree or disagree; suggest alternatives 
and substitute language for your requested changes.
     Describe any assumptions and provide any technical 
information and/or data that you used.
     If you estimate potential costs or burdens, explain how 
you arrived at your estimate in sufficient detail to allow it to be 
reproduced.
     Illustrate your concerns with specific examples and 
suggest alternatives.
     Explain your views as clearly as possible, avoiding the 
use of profanity or personal threats.
     Make sure to submit your comments by the comment period 
deadline identified.

II. What is the WIPP?

    The WIPP is a disposal system for defense-related transuranic (TRU) 
radioactive waste. Developed by the DOE, the WIPP is located near 
Carlsbad in southeastern New Mexico. At the WIPP, radioactive waste is 
disposed of 2,150 feet underground in an ancient formation of salt 
which will eventually ``creep'' and encapsulate the waste. The WIPP has 
a total capacity of 6.2 million cubic feet of waste.
    Congress authorized the development and construction of the WIPP in 
1980 ``for the express purpose of providing a research and development 
facility to demonstrate the safe disposal of radioactive wastes 
resulting from the defense activities and programs of the United 
States.'' \1\ Waste which may be

[[Page 72614]]

emplaced in the WIPP is limited to TRU radioactive waste generated by 
defense activities associated with nuclear weapons; no high-level waste 
or spent nuclear fuel from commercial power plants may be disposed of 
at the WIPP. TRU waste is defined as materials containing alpha-
emitting radioisotopes, with half lives greater than twenty years and 
atomic numbers above 92, in concentrations greater than 100 nano-curies 
per gram of waste.\2\ Most TRU waste proposed for disposal at the WIPP 
consists of items that have become contaminated as a result of 
activities associated with the production of nuclear weapons (or with 
the clean-up of weapons production facilities), e.g., rags, equipment, 
tools, protective gear, soil and organic or inorganic sludges. Some TRU 
waste is mixed with hazardous chemicals. The waste proposed for 
disposal at the WIPP is currently located at federal facilities across 
the United States, including locations in California, Idaho, Illinois, 
New Mexico, Nevada, Ohio, South Carolina, Tennessee and Washington.
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    \1\ Department of Energy National Security and Military 
Applications of Nuclear Energy Authorization Act of 1980, Public Law 
96-164, section 213.
    \2\ WIPP Land Withdrawal Act, Pub. L. 102-579, section 2(18), as 
amended by the 1996 WIPP LWA Amendments, Pub. L. 104-201.
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    The WIPP Land Withdrawal Act (LWA), initially passed by Congress in 
1992 and amended in 1996, provides the EPA authority to oversee and 
regulate the WIPP. The WIPP LWA delegated to the EPA three main tasks, 
to be completed sequentially, for reaching an initial compliance 
certification decision. First, the Agency was required to finalize 
general regulations which apply to all sites--except Yucca Mountain--
for the disposal of highly radioactive waste.\3\ These disposal 
regulations, located at Subparts B and C of 40 CFR part 191, were 
originally published in the Federal Register in 1985 and amended in 
1993.\4\ Second, the EPA was to develop criteria, by rulemaking, to 
implement and interpret the general radioactive waste disposal 
regulations specifically for the WIPP. In 1996, the Agency issued the 
WIPP Compliance Criteria, which are found at 40 CFR part 194.\5\ The 
EPA made changes to the Compliance Criteria via rulemaking in July 2004 
(69 FR 42571-42583). These new provisions provide equivalent or 
improved oversight and better prioritization of technical issues in EPA 
inspections to evaluate waste characterization activities at DOE WIPP 
waste generator sites, and offer more direct public input into the 
Agency's decisions about what waste can be disposed of at the WIPP. 
Third, the EPA was to review the information submitted by the DOE and 
publish a certification decision.\6\ The Agency issued its 
certification decision on May 18, 1998, as required by Section 8 of the 
WIPP LWA (63 FR 27354-27406) determining that the WIPP met the 
standards for radioactive waste disposal. The complete record and basis 
for the EPA's 1998 certification decision can be found in Air Docket A-
93-02. Condition 1, concerning the panel closure system, was appended 
to 40 CFR part 194 as part of the certification decision.
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    \3\ WIPP LWA, section 8(b).
    \4\ 50 FR 38066-38089 (September 19, 1985) and 58 FR 66398-66416 
(December 20, 1993).
    \5\ 61 FR 5224-5245 (February 9, 1996).
    \6\ WIPP LWA, section 8(d).
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    Section 8(f) of the WIPP LWA requires that within five years of 
initial receipt of waste at the WIPP, and every five years thereafter, 
the DOE is to submit to the EPA and the State of New Mexico 
documentation of continued compliance with the part 191 radioactive 
waste disposal regulations. The Agency recertified the WIPP facility 
for the first time on March 29, 2006 (71 FR 18010-18021) and again on 
November 18, 2010 (75 FR 70584-70595).
    The Department submitted the design of the WIPP repository in 
Chapter 3 of the 1996 Compliance Certification Application (CCA). The 
EPA's certification is based upon this design. The underground waste 
disposal region at WIPP is divided into panels. A panel is a group of 
rooms mined into the salt, connected by tunnels called drifts. When all 
of the rooms of a panel are filled with waste, the DOE intends to seal 
the drifts with engineered structures called panel closures. The EPA 
certified the WIPP based on a panel closure design that sealed the 
drift using a concrete block wall and a poured concrete monolith. The 
DOE proposes to change this design and close the drift using two steel 
bulkheads and mined salt. Both panel closure designs are discussed in 
detail in Section IV of this document.

III. What is the purpose of today's proposed action?

    This action is being taken in response to the DOE's September 2011 
Planned Change Request (PCR) to alter the design of the panel closures 
used at the WIPP. The WIPP underground waste disposal area is divided 
into ten groups of rooms, or panels. A waste panel is a group of mined 
rooms connected by drifts that provide both access and ventilation to 
the rooms. Following completion of waste disposal activities in each 
panel, the DOE intends to seal these drifts with engineered structures 
called panel closures. 40 CFR part 194, Criteria for the Certification 
and Recertification of the Waste Isolation Pilot Plant's Compliance 
with the 40 CFR part 191 Disposal Regulations, did not originally 
require panel closures for the purpose of long-term compliance with 
release limits for radionuclides. Panel closures have, however, always 
been included in the design of the repository, and therefore 
incorporated into modeling of the WIPP system as a feature of the 
repository.

[[Page 72615]]

[GRAPHIC] [TIFF OMITTED] TP03DE13.010

    Although the Agency determined that the DOE met all of the 
applicable requirements of the WIPP Compliance Criteria in its 
compliance certification decision (63 FR 27354-27406; May 18, 1998), 
the EPA amended the WIPP Compliance Criteria, 40 CFR part 194, and 
appended four explicit conditions to its certification of compliance to 
ensure that the measures actually implemented at the WIPP (and thus the 
circumstances expected to exist there) were consistent with the DOE's 
Compliance Certification Application (CCA) and with the basis for the 
EPA's compliance certification. Condition 1 of the certification 
applies to the panel closure system.\7\ In the CCA, the Department 
presented four options for the design of the panel closure system, but 
did not specify which would be constructed at the WIPP facility. The 
Agency based its certification decision on the DOE's use of the most 
robust design, referred to in the CCA as ``Option D''.
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    \7\ Conditions 2 and 3 of the final certification decision apply 
to activities conducted at waste generator sites that produce TRU 
waste proposed for disposal at WIPP (Sec. Sec.  194.22 and 194.24), 
and Condition 4 of the certification applies to passive 
institutional controls (PICs), records and physical markers to warn 
future societies about the location and contents of the disposal 
system and thus to deter inadvertent intrusion into the WIPP (Sec.  
194.43).
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    At the time of the 1998 certification decision, there were 
indications that the DOE would seek to change the design of the panel 
closure system selected by the EPA. As stated in the original 
certification:

    Nothing in this condition precludes DOE from reassessing the 
engineering of the panel seals at any time. Should DOE determine at 
any time that improvements in materials or construction techniques 
warrant changes to the panel seal design, DOE must inform EPA. If 
EPA concurs, and determines that such changes constitute a 
significant departure from the design on which certification is 
based, the Agency is authorized under Sec.  194.65 to initiate a 
rulemaking to appropriately modify the certification.'' (63 FR 
27354, 27362; May 18, 1998.)

    In 2002, the Agency approved the DOE's request to install only the 
explosion wall, and to extend the panel closure installation schedule 
until a new design is approved. In January 2007, the DOE requested that 
installation of the explosion walls also be delayed until a new design 
could be approved, and proposed to monitor gas generation in Panels 3 
and 4 of the repository. The EPA approved this request in February 
2007. Today's action represents the first time that the Agency has 
considered an alteration to the panel closure design itself.
    The Department submitted a PCR to the EPA on September 28, 2011. 
Citing

[[Page 72616]]

experience and data gained since the CCA, the DOE's PCR states that the 
Option D panel closure would be extremely difficult and costly to 
install, and that the highly engineered design is unnecessary for 
either worker safety or environmental protection during the operational 
period. The DOE instead proposed a new panel closure design, the Run-
of-Mine Salt Panel Closure System (ROMPCS), which consists of mined 
salt emplaced between steel bulkheads.
    The EPA has completed its technical review of the DOE's PCR and 
supporting documentation. The goal of the Agency's technical review 
process was to determine whether, with the new design, the WIPP 
adequately demonstrates compliance with the requirements of 40 CFR part 
194 and the release limits of 40 CFR part 191 Subparts B and C. The 
process the EPA applied to support this proposed action entailed (1) a 
review of all materials submitted by the DOE, (2) requests for 
additional information including a full performance assessment, and (3) 
the independent performance of additional confirmatory calculations by 
the Agency. This process is fully documented in the EPA's TSD, ``Review 
of the DOE's Planned Change Request to Modify the WIPP Panel Closure 
System,'' (EPA-HQ-OAR-2013-0684-0002) and discussed in the following 
sections. Based on this process, the Agency concludes that the WIPP 
will remain in compliance with its release limits with the ROMPCS 
design. The Agency therefore proposes to approve the DOE's PCR to 
implement the redesigned panel closure at the WIPP, and to modify 40 
CFR part 194 Appendix A, Condition 1 to allow a panel closure design 
other than Option D. Section IV, below, discusses the Agency's 
consideration of the proposed panel closure modification. Section V 
describes the Agency's approach to modifying Condition 1.

IV. How is the EPA responding to the DOE's planned change request?

A. What are the EPA's requirements for the panel closure design?

    During the operational period of the repository, the panel closure 
system was intended to prevent access to closed waste panels, to 
mitigate the release of volatile organic compounds (VOCs) and to 
protect site workers from a hypothetical methane or hydrogen explosion 
inside a filled waste panel. These functions are addressed by the New 
Mexico Environment Department (NMED), and DOE has submitted a separate 
Resource Conservation and Recovery Act (RCRA) Permit Modification 
Request (PMR) stating that the new panel closure design will adequately 
protect workers and the public during the operational period of the 
WIPP.
    The EPA's Compliance Criteria at 40 CFR part 194 originally did not 
require a panel closure of any kind to be installed in the repository 
for the purpose of long-term compliance with release limits for 
radionuclides. The purpose of 40 CFR part 194 is to demonstrate 
compliance with the disposal regulations at 40 CFR part 191 for 
containment of radionuclides. The containment requirements at 40 CFR 
191.13 specify that releases of radionuclides to the accessible 
environment must be unlikely to exceed specific release limits for 
10,000 years after disposal, based on the amount of waste in the 
repository at the time of closure (Sec.  194.31). Assessment of the 
likelihood that the WIPP will not exceed release limits is accomplished 
through a process called performance assessment, or PA. The WIPP PA 
process culminates in a series of computer simulations that model the 
physical attributes of the disposal system (e.g., site characteristics, 
waste forms and quantities, engineered features) in a manner that 
captures the behaviors and interactions among its various components. 
The computer simulations require the development of conceptual models 
that represent physical attributes of the repository based on features, 
events and processes (FEPs) that may impact the disposal system. The 
conceptual models are then expressed as mathematical relationships, 
which are solved with iterative numerical models, which are then 
translated into computer codes (Sec.  194.23). Numerous simulations are 
performed using sampled values for material properties and processes 
whose values are uncertain. The results of the simulations are intended 
to calculate possible releases of radioactive materials from the 
disposal system to the accessible environment over the 10,000-year 
regulatory period, and are used to demonstrate compliance with the 
containment requirements in 40 CFR 191.13. Because the radionuclide 
release limits are based on the amount of waste in the repository at 
the time of closure, the containment requirements are expressed in 
terms of ``normalized releases.'' The results of the PA are assembled 
into complementary cumulative distribution functions (CCDFs), which 
indicate the probability of exceeding various levels of normalized 
releases (Sec.  194.34).
    At the time of the CCA, given limited information on how the 
different panel closure designs could influence performance, the Agency 
contended that the panel closures constructed in the repository should 
have physical properties similar to those that had been used to 
represent them in the compliant performance assessment. As stated in 
the WIPP certification:

EPA based its certification decision on DOE's use of the most robust 
design (referred to in the CCA as ``Option D''). The Agency found 
the Option D design to be adequate, but also determined that the use 
of Salado mass concrete--using brine rather than fresh water--would 
produce concrete seal permeabilities in the repository more 
consistent with the values used in DOE's performance assessment. 
Therefore, Condition 1 of EPA's certification requires DOE to 
implement the Option D panel closure system at WIPP, with Salado 
mass concrete replacing fresh water concrete. (63 FR 27355)

Because the Agency based its certification of the WIPP's compliance 
with the disposal regulations on the accurate representation of the 
repository in performance assessment, Condition 1 was appended to 40 
CFR Part 194 during the certification of the WIPP. No other design 
feature of the repository is required by the Compliance Criteria in a 
similarly explicit way.

B. What changes are proposed to the panel closure design?

    The Option D panel closure design consists of a 12-foot thick 
``explosion-isolation wall'' constructed of solid concrete blocks 
filling the drift on the waste disposal side, a short section of open 
drift called an ``isolation zone'' and a monolithic concrete barrier on 
the side of the open drift. Fractured rock in the immediate vicinity of 
the drift--called the disturbed rock zone, or DRZ--would be removed, 
and the resulting void space filled by the concrete monolith. In its 
current PCR, the DOE states that ``large scale testing has demonstrated 
that using SMC [Salado Mass Concrete] cannot meet the design and 
performance requirements for the panel closures as specified in the 
CCA.'' Even if the Option D monolith could be constructed as planned, 
the Agency acknowledges that it would be installed at significant cost 
to the Department, that additional occupational hazards would be 
incurred by moving and pouring large amounts of concrete in the 
underground and that disposal operations would be significantly 
disrupted.
    The DOE's new panel closure design, the ROMPCS, consists primarily 
of run-of-mine (ROM) salt--impure halite that

[[Page 72617]]

has been mined in the course of normal repository operations and not 
subjected to additional processing or grading. The ROMPCS design 
consists of two standard steel ventilation bulkheads with a minimum of 
100 feet of run-of-mine (ROM) salt between them, filling the drift from 
floor to ceiling. In Panels 1, 2 and 5, where explosion walls have 
already been constructed, salt will be placed directly against the 
explosion wall and a standard steel ventilation bulkhead placed on the 
outer end of the panel closure. The DOE has stated that the ROMPCS will 
provide adequate protection during the operational period. Upon initial 
emplacement, the run-of-mine salt will exhibit the properties of a 
loosely consolidated or unconsolidated material. Over time, as the open 
areas of the repository close due to salt creep, the panel closures 
will consolidate and eventually heal to a state resembling intact salt.
    The EPA's technical review process is summarized below in Section 
C. Based on the results of performance assessment, the Agency concludes 
that the WIPP will continue to comply with the EPA's disposal standards 
with the ROMPCS. Therefore, the Agency proposes to approve the DOE's 
PCR and allow the implementation of the ROMPCS design at the WIPP.

C. How has the EPA reached its decision?

    As in the past, the Agency's consideration of the panel closure 
system focused on its inclusion and accurate representation in 
repository performance assessment, so that the EPA can ultimately 
certify the WIPP's ability to meet long-term performance standards.
    In support of its panel closure PCR, the DOE initially submitted a 
performance assessment calculation called the Panel Closure Redesign 
and Repository Reconfiguration (PC3R) PA, which incorporated multiple 
planned changes. The Agency determined that to approve the PCR, it was 
necessary to isolate the impacts, if any, of the change in panel 
closure design. In response, the DOE prepared the PCS-2012 PA, with the 
explicit goal of changing only those aspects of the current baseline PA 
that are directly related to the change in the panel closure design. 
Thus, results of the PCS-2012 PA may be directly compared to results of 
the current Performance Assessment Baseline Calculation (PABC-09) to 
see the impact of changes in the panel closure on modeled releases from 
the facility.
    The majority of the technical effort expended by the Agency was 
spent determining how the changes in the panel closures should be 
represented in the performance assessment models. This review process 
involved interactions with the DOE and DOE contractor staff and is 
documented in the Agency's TSD, ``Review of DOE's Planned Change 
Request to Modify the WIPP Panel Closure System.'' (EPA-HQ-OAR-2013-
0684-0002) The process began by identifying the universe of changes 
which might have taken place within the performance assessment. The 
conclusion of the features, events and processes (FEPs) review found 
that the required changes to the models were limited to the properties 
of the panel closure and of the disturbed rock zone immediately 
surrounding it. In performance assessment, these materials are 
represented in the BRAGFLO computer model, which simulates the flow of 
brine and gas in the repository over the 10,000-year period of 
performance. Some modeling changes, such as differences between the 
physical dimensions of the panel closure designs, were relatively 
simple for the DOE to implement. The most significant change between 
panel closure designs, and the greatest modeling challenge, was the 
dynamic nature of the ROMPCS's material properties. The Option D design 
called for the excavation of the DRZ, and the installation of a rigid 
concrete monolith which would effectively prevent further fracturing. 
Thus, the properties of the panel closure and surrounding DRZ were not 
expected to change significantly over time, and were represented in PA 
by constant values. The ROMPCS will be emplaced in a loose form, 
surrounded by a fractured DRZ. As the panel closure system consolidates 
due to repository creep closure, it will decrease in porosity, and its 
permeability to fluids will decrease. Based on measurements taken in 
the underground, laboratory data and geomechanical modeling, it is 
expected that this consolidation process will be complete approximately 
200 years after the closure of the repository.
    The DOE represents the ROMPCS using three time periods. Two time 
periods of one hundred years each are used to represent the gradual 
reconsolidation of the panel closure system. A third time period, 
extending from 200 years after closure to the end of the 10,000-year 
performance period, represents the final healed state of the PCS. The 
consolidation of the ROMPC is modeled by sampling its porosity from a 
range of possible values for each time period. The permeability of the 
panel closure to fluids during each time period is then calculated 
using a correlation between the porosity and permeability of salt, 
developed by the DOE using existing experimental data. The DRZ 
surrounding the panel closure is modeled so that it is more permeable 
to fluids during the first 200 years after closure, and less permeable 
when the system has reached a steady state. Parameter values 
representing other material properties of the ROM salt were directly 
adopted from parameters that were developed during the CCA to describe 
the crushed salt component of the shaft seals. The parameters used to 
represent the changes in performance assessment were finalized by the 
DOE in a memorandum dated May 3, 2012.
    After the EPA's concurrence with the representation of the panel 
closure, the DOE executed the PCS-2012 PA calculation. Results of the 
PCS-2012 PA are discussed in detail in TSD Section 4.5. Compared to the 
PABC-2009 baseline, calculated mean total releases from the PCS-2012 PA 
did not appreciably increase at a probability of 0.1, and increased at 
a probability of 0.001, from 1.1 to 1.51 EPA units. (See TSD, EPA-HQ-
OAR-2013-0684-0002, Table 3.7.) Thus, the mean total release, as well 
as the 90th percentile and upper 95% confidence limit of the mean, fell 
significantly below the Agency's regulatory limits of 1 EPA unit for a 
probability of 0.1, and 10 EPA units for a probability of 0.001.
    Modeled releases from the repository principally result from the 
penetration of the repository waste by a hypothetical oil or gas 
borehole. Specific release mechanisms include cuttings and cavings 
releases, direct brine releases (DBRs), spallings releases and releases 
up a borehole to the Culebra dolomite. The increase in calculated 
releases in the PCS-2012 PA is primarily due to increases in direct 
brine releases, resulting from changes in pressure and brine saturation 
in the waste panels (See TSD, EPA-HQ-OAR-2013-0684-0002, Section 3.5). 
Compared to the Option D PCS design, the ROMPCS is expected to be more 
permeable to fluids upon installation, and less permeable after it has 
consolidated. The initial conditions of the WIPP model make a 
significant amount of brine available in the repository at the time of 
closure. The higher initial permeability of the ROMPCS allows early-
time brine inflows into the waste panels, resulting in generally higher 
brine saturations and higher rates of gas generation in the modeled 
waste panel. When the permeability of the panel closures decreases 
after 200 years, both brine and gas can be retained in the panel, 
increasing the brine saturations and gas pressures encountered by 
borehole

[[Page 72618]]

penetrations of the repository. Those increases in turn result in 
increases in mean DBR and spallings releases. Cuttings and cavings are 
important contributors to total releases, but are not affected by waste 
panel pressure and brine saturation. Releases through the Culebra are 
essentially unchanged from those calculated using the Option D design.
    The EPA considers this analysis important to its understanding of 
the disposal system. The Agency concludes that the changes to the panel 
closure system do not have a significant impact on the long-term 
performance of the disposal system.

V. How is the EPA revising Appendix A, Condition 1?

A. What are the current requirements of Appendix A, Condition 1?

    The Option D panel closure is currently required by 40 CFR part 
194, Appendix A, Condition 1.
    As described in Section III, the EPA certified the WIPP's 
performance based on the properties of the Option D panel closure. It 
is the only engineered aspect of the repository design that is 
explicitly required by rule.

B. What changes are proposed for Appendix A, Condition 1?

    As described above in Section IV, the EPA is proposing to accept a 
redesigned panel closure. Acceptance of the PCR requires modification 
of Condition 1. The Agency does not believe that the design must be 
specified by the condition, because there is no evidence to suggest 
that the panel closure has a disproportionate ability to impact long-
term performance when compared to other design features of the 
repository. This change does not grant the DOE the ability to alter the 
panel closure design at will. As with any engineered component of the 
disposal system, a departure from the current, approved design must be 
submitted to the Agency as a planned change request as required by 
Sec.  194.4(b)(3)(i). The EPA would expect any such request to be 
supported by complete technical documentation, including information 
concerning ``the geology, hydrology, hydrogeology, and geochemistry of 
the WIPP disposal system'' and ``WIPP materials of construction, 
standards applied to design and construction,'' as required by Sec.  
194.14, Content of certification applications. The Agency would use 
this information to determine whether or not the WIPP remains in 
compliance with the disposal standards. As with any other planned 
change, based on the potential impact to the WIPP's compliance, the EPA 
will determine whether the change ``departs significantly from the most 
recent compliance application,'' and must be addressed by rule in 
accordance with Sec.  194.65.

C. What did the EPA consider when making its decision?

    In 1998, the EPA certified the WIPP conditionally based on the 
Option D panel closure design. At that time, the DOE had not specified 
which design it planned to implement, and limited performance 
assessment results were available to indicate the impact of the panel 
closure design on repository performance. In contrast, the Department 
has now proposed a single panel closure design to be installed in all 
waste panels. Due to the evolution of the WIPP PA since the CCA, the 
DOE and the EPA have gained a greater understanding of panel closures' 
influence on PA results.
    The Agency initially chose the Option D panel closure partly to 
match the physical properties of the panel closure to the modeled 
parameters of the generic panel closure represented in the CCA. This 
representation of the panel closure was refined in the 2002 Technical 
Baseline Migration PA to reflect the dimensions of the Option D design 
and include impacts of a rigid structure on the surrounding DRZ. These 
changes did not result in a significant impact on predicted releases, 
and were included in PAs which supported both WIPP recertifications. 
The changes made in the PCS-2012 PA altered the panel closure 
properties substantially, without significantly affecting the WIPP's 
ability to comply with the release limits. The DOE's sensitivity 
analysis indicates that several sampled parameters related to the panel 
closures contributed to the overall results, but their contributions 
were dwarfed by the effect of other parameters, such as the waste shear 
strength and actinide solubility. Additionally, the Agency carried out 
confirmatory studies as part of its technical review which analyzed how 
different representations of the DRZ surrounding the panel closure 
could potentially influence modeled results.
    The conclusion that the Agency draws from all of these studies is 
that although the panel closures can influence modeled results to a 
degree, there is no evidence that modifications to the panel closure or 
its representation in PA could jeopardize the WIPP's ability to comply 
with the disposal requirements. Because panel closures do not exercise 
a disproportionate impact on the WIPP's ability to isolate 
radionuclides from the accessible environment, the EPA does not believe 
that it is necessary for the specific design of the panel closure to 
remain as a condition of certification. Rather, panel closures can be 
treated in a similar manner as any other engineered feature of the 
repository. As described in Section IV, the DOE must still submit a PCR 
if it wishes to alter the design from the approved ROMPCS.

VI. How has the EPA involved the public?

    In order to guide its technical process, the EPA held informal 
public meetings in Carlsbad, New Mexico, on December 5, 2012, and Santa 
Fe, New Mexico, on December 6, 2012. The purpose of these meetings was 
to provide the public with background on the DOE's panel closure system 
planned change request, and to give the public the opportunity to raise 
any technical issues that the Agency should consider in its decision. 
At both meetings, many comments were in favor of approving the panel 
closure planned change request based on its scientific and economic 
merits. Specifically, commenters expressed confidence in the ability of 
salt creep to compress the ROMPCS and form an adequate panel closure, 
and emphasized the greater operational safety when installing the 
revised design. In Santa Fe, one commenter expressed the view that the 
lack of a cost analysis for building the Option D panel closures, and 
the failure to explicitly consider other designs are deficiencies in 
the PCR. Other commenters asked questions regarding the likelihood of 
gas generation and explosions in the closed panels. No technical 
comments were submitted.
    Additional public meetings will be held in Carlsbad and Albuquerque 
in December 2013. Details and summaries of these meetings will be 
published on the EPA's WIPP Web site at http://www.epa.gov/radiation/wipp.

VII. Administrative Requirements

A. Executive Order 12866

    Under Executive Order 12866, (58 FR 51735; October 4, 1993), the 
Agency must determine whether the regulatory action is ``significant'' 
and therefore subject to OMB review and the requirements of the 
Executive Order. The Order defines ``significant regulatory action'' as 
one that is likely to result in a rule that may: (1) Have an annual 
effect on the economy of $100 million or more or adversely affect in a 
material way the economy, a sector of the economy, productivity, 
competition, jobs, the environment, public health or safety, or state, 
local, or tribal governments or communities; (2) create

[[Page 72619]]

a serious inconsistency or otherwise interfere with an action taken or 
planned by another Agency; (3) materially alter the budgetary impact of 
entitlements, grants, user fees or loan programs or the rights and 
obligations of recipients thereof; or (4) raise novel legal or policy 
issues arising out of legal mandates, the President's priorities or the 
principles set forth in the Executive Order. Pursuant to the terms of 
Executive Order 12866, it has been determined that this rule is not a 
``significant regulatory action.''

B. Regulatory Flexibility Act

    The Regulatory Flexibility Act (``RFA'') generally requires any 
federal agency to conduct a regulatory flexibility analysis of any rule 
subject to notice and comment rulemaking requirements unless they 
certify that the rule will not have a significant economic impact on a 
substantial number of small entities. Small entities include small 
businesses, small not-for-profit enterprises and small governmental 
jurisdictions. This proposed rule will not have a significant impact on 
a substantial number of small entities because it sets forth 
requirements which apply only to federal agencies. Therefore, this 
action will not have a significant economic impact on a substantial 
number of small entities.

C. Paperwork Reduction Act

    This proposed action does not impose an information collection 
burden under the provisions of the Paper Reduction Act, 44 U.S.C. 3501 
et seq. The Compliance Criteria in 40 CFR part 194 requirements are 
applicable only to the DOE and the EPA and do not establish any form of 
collection of information from the public.

D. Unfunded Mandates Reform Act

    Title II of the Unfunded Mandates Reform Act of 1995 (``UMRA''), 
Public Law 104-4, establishes requirements for federal agencies to 
assess the effects of their regulatory actions on state, local and 
tribal governments and the private sector. Pursuant to Title II of the 
UMRA, we have determined that this regulatory action is not subject to 
the requirements of sections 202 and 205, because this action does not 
contain any ``federal mandates'' for state, local or tribal governments 
or for the private sector. This rule applies only to federal agencies.

E. Executive Order 12898

    Pursuant to Executive Order 12898 (59 FR 7629; February 16, 1994), 
entitled ``Federal Actions to Address Environmental Justice in Minority 
Populations and Low-Income Populations,'' the Agency has considered 
environmental justice related issues with regard to the potential 
impacts of this action on the environmental and health conditions in 
low-income, minority and Native-American communities. We have complied 
with this mandate. However, the requirements specifically set forth by 
the Congress in the Waste Isolation Pilot Plant Land Withdrawal Act 
(Pub. L. 102-579), which prescribes the EPA's role at the WIPP, did not 
provide authority for the Agency to examine impacts in the communities 
in which wastes are produced, stored and transported, and Congress did 
not delegate to the EPA the authority to consider the issue of 
alternative locations for the WIPP. During the development of the 
existing provisions in 40 CFR part 194, the EPA involved minority and 
low income populations early in the rulemaking process. In 1993, the 
EPA representatives met with New Mexico residents and government 
officials to identify the key issues that concern them, the types of 
information they wanted from the Agency and the best ways to 
communicate with different sectors of the New Mexico public. The 
feedback provided by this group of citizens formed the basis for the 
EPA's WIPP communications and consultation plan. To help citizens 
(including a significant Hispanic population in Carlsbad and the nearby 
Mescalero Indian Reservation) stay abreast of the EPA's WIPP-related 
activities, the Agency developed many informational products and 
services. The EPA translated several documents regarding WIPP into 
Spanish, including educational materials and fact sheets describing the 
EPA's WIPP oversight role and the radioactive waste disposal standards. 
The Agency established a toll-free WIPP Information Line, recorded in 
both English and Spanish, providing the latest information on upcoming 
public meetings, publications and other WIPP-related activities. The 
EPA also developed a mailing list, which includes many low-income, 
minority and Native-American groups, to systematically provide 
interested parties with copies of EPA's public information documents 
and other materials. Even after the final rule, in 1998, the EPA has 
continued to implement outreach services to all WIPP communities based 
on the needs determined during the certification. The Agency has 
established a WIPP-NEWS email listserv to facilitate communications 
with interested stakeholders not only in New Mexico and surrounding 
areas, but nationally and internationally as well. The EPA's WIPP Web 
site is also continuously updated with relevant news and updates on 
current and future WIPP activities.

F. National Technology Transfer & Advancement Act of 1995

    Section 12 of the National Technology Transfer & Advancement Act of 
1995 is intended to avoid ``re-inventing the wheel.'' It aims to reduce 
costs to the private and public sectors by requiring federal agencies 
to draw upon any existing, suitable technical standards used in 
commerce or industry. To comply with the Act, the EPA must consider and 
use ``voluntary consensus standards,'' if available and applicable, 
when implementing policies and programs, unless doing so would be 
``inconsistent with applicable law or otherwise impractical.'' We have 
determined that this regulatory action is not subject to the 
requirements of National Technology Transfer & Advancement Act of 1995 
as this rulemaking is not setting any technical standards.

G. Executive Order 13045: Children's Health Protection

    This rule is not subject to Executive Order 13045, entitled 
``Protection of Children from Environmental Health Risks and Safety 
Risks'' (62 FR 19885; April 23, 1997) because it does not involve 
decisions on environmental health risks or safety risks that may 
disproportionately affect children.

H. Executive Order 13132: Federalism

    Executive Order 13132, entitled ``Federalism'' (64 FR 43255; August 
10, 1999), requires the EPA to develop an accountable process to ensure 
``meaningful and timely input by state and local officials in the 
development of regulatory policies that have federalism implications.'' 
``Policies that have federalism implications'' is defined in the 
Executive Order to include regulations that have ``substantial direct 
effects on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government.'' This 
proposed rule does not have federalism implications. It will not have 
substantial direct effects on the states, on the relationship between 
the national government and the states or on the distribution of power 
and responsibilities among the various levels of government, as 
specified in Executive Order 13132. This proposed

[[Page 72620]]

action revises a specific condition of the Compliance Criteria in 40 
CFR part 194. These criteria are applicable only to the DOE (operator) 
and the EPA (regulator) of the WIPP disposal facility. Thus, Executive 
Order 13132 does not apply to this rule. In the spirit of Executive 
Order 13132, and consistent with the Agency's policy to promote 
communications between the EPA and state and local governments, the EPA 
specifically solicits comment on this proposed rule from state and 
local officials.

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

    Executive Order 13175, entitled ``Consultation and Coordination 
with Indian Tribal Governments'' (65 FR 67249; November 9, 2000), 
requires the EPA to develop an accountable process to ensure 
``meaningful and timely input by tribal officials in the development of 
regulatory policies that have tribal implications.'' This proposed rule 
does not have tribal implications, as specified in Executive Order 
13175. This proposed action revises a condition of the Compliance 
Criteria in 40 CFR part 194. The Compliance Criteria are applicable 
only to Federal agencies. Thus, Executive Order 13175 does not apply to 
this rule. In the spirit of Executive Order 13175, and consistent with 
the EPA policy to promote consultation and coordination with Indian 
Tribal Governments, the Agency specifically solicits comment on this 
proposed rule from Tribal officials.

J. Executive Order 13211: Energy Effects

    This proposed rule is not subject to Executive Order 13211, 
``Actions Concerning Regulations That Significantly Affect Energy 
Supply, Distribution, or Use'' (66 FR 28355; May 22, 2001) because it 
is not a significant regulatory action under Executive Order 12866.

    Dated: November 18, 2013.
Janet G. McCabe,
Acting Assistant Administrator, Office of Air and Radiation.

    For the reasons set out in the preamble, 40 CFR part 194 is 
proposed to be amended as follows:

PART 194--CRITERIA FOR THE CERTIFICATION AND RECERTIFICATION OF THE 
WASTE ISOLATION PILOT PLANT'S COMPLIANCE WITH THE 40 CFR PART 191 
DISPOSAL REGULATIONS

0
1. The authority citation for part 194 continues to read as follows:

    Authority: Pub. L. 102-579, 106 Stat. 4777, as amended by Public 
Law 104-201, 110 Stat. 2422; Reorganization Plan No. 3 of 1970, 35 
FR 15623, Oct. 6, 1970, 5 U.S.C. app. 1; Atomic Energy Act of 1954, 
as amended, 42 U.S.C. 2011-2296 and 10101-10270.
0
2. Amend Appendix A to Part 194 by revising Condition 1: Sec.  
194.14(b) to read as follows:

Appendix A to Part 194--Certification of the Waste Isolation Pilot 
Plant's Compliance With the 40 CFR Part 191 Disposal Regulations and 
the 40 CFR Part 194 Compliance Criteria

* * * * *
    Condition 1: Sec.  194.14(b), Disposal system design, panel 
closure system. The Department shall close filled waste panels in a 
manner that has been specifically approved by the Agency. Any 
modification to the approved panel closure design must be submitted 
by the DOE as a planned change request pursuant to Sec.  
194.4(b)(3)(i), and include supporting information required by Sec.  
194.14, Content of compliance certification application. The 
Administrator or Administrator's authorized representative will 
determine whether the planned change differs significantly from the 
design included in the most recent compliance certification, and 
whether the planned change would require modification of the 
compliance criteria. The EPA's approval of a panel closure change 
request requires that performance assessment calculations adequately 
represent the waste panel closure design, and that those 
calculations demonstrate the WIPP's compliance with the release 
standards set by 40 CFR part 191, Subpart B in accordance with Sec.  
194.34, Results of performance assessments.
* * * * *
[FR Doc. 2013-28240 Filed 12-2-13; 8:45 am]
BILLING CODE 6560-50-P