[Federal Register Volume 81, Number 120 (Wednesday, June 22, 2016)]
[Notices]
[Pages 40685-40689]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-14775]


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DEPARTMENT OF ENERGY


Production of Tritium in Commercial Light Water Reactors

AGENCY: National Nuclear Security Administration, Department of Energy.

ACTION: Record of Decision.

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SUMMARY: The National Nuclear Security Administration (NNSA), a 
separately organized agency within the Department of Energy (DOE), is 
issuing this Record of Decision (ROD) for the Final Supplemental 
Environmental Impact Statement for the Production of Tritium in a 
Commercial Light Water Reactor (CLWR SEIS) (DOE/EIS-0288-S1) issued on 
March 4, 2016.
    NNSA prepared the CLWR SEIS to update the environmental analyses in 
the 1999 Final Environmental Impact Statement for the Production of 
Tritium in a Commercial Light Water Reactor (DOE/EIS-0288; the 1999 
EIS). The CLWR SEIS provides analysis of the potential environmental 
impacts from Tritium Producing Burnable Absorber Rod (TPBAR) 
irradiation based on a conservative estimate of the tritium permeation 
rate through the TPBAR cladding, NNSA's revised estimate of the maximum 
number of TPBARs necessary to support the current and projected future 
tritium supply requirements, and a maximum production scenario of 
irradiating no more than a total of 5,000 TPBARs every 18 months.
    NNSA has decided to implement the Preferred Alternative, 
Alternative 6, which allows for the irradiation of up to a total of 
5,000 TPBARs every 18 months using Tennessee Valley Authority (TVA) 
reactors at both the Watts Bar and Sequoyah sites. Although near-term 
tritium requirements could likely be met with the irradiation of 2,500 
TPBARs every 18 months, this decision provides the greatest flexibility 
to meet potential future needs that could arise from various plausible 
but unexpected events. The exact number of TPBARs to be irradiated 
during each/any 18-month reactor core cycle will be determined by both 
national security requirements and TVA reactor availability.
    The CLWR SEIS analyses indicate that there would not be any 
significant increase in radiation exposure associated with TPBAR 
irradiation for facility workers or the public. For all analyzed 
alternatives, estimated radiation exposures would remain well below 
regulatory limits. The calculated estimated exposures for normal 
reactor operations with even the maximum number of TPBARs are 
comparable to those for normal reactor operation without TPBARs.

FOR FURTHER INFORMATION CONTACT: For further information on the CLWR 
SEIS, or this ROD, or to receive a copy of the CLWR SEIS, contact: Mr. 
Curtis Chambellan, CLWR SEIS Document Manager, P.O. Box 5400, 
Albuquerque, New Mexico 87185-5400; 505-845-5073; 
[email protected].
    For information on the DOE National Environmental Policy Act (NEPA) 
process, contact: Ms. Carol M. Borgstrom, Director, Office of NEPA 
Policy and Compliance (GC-54), U.S. Department of Energy, 1000 
Independence Avenue SW., Washington, DC 20585; (202) 586-4600, or leave 
a message at (800) 472-2756. This ROD, the CLWR SEIS, and related NEPA 
documents are available on the DOE NEPA Web site at www.energy.gov/nepa 
and on NNSA's NEPA Web site at http://nnsa.energy.gov/aboutus/ouroperations/generalcounsel/nepaoverview/nepa/tritiumseis.

SUPPLEMENTARY INFORMATION: 

Background

    NNSA is the lead Federal agency responsible for maintaining and 
enhancing the safety, security, reliability, and performance of the 
United States (U.S.) nuclear weapons stockpile. Tritium, a radioactive 
isotope of hydrogen, is an essential component of every weapon in the 
U.S. nuclear weapons stockpile and must be replenished periodically due 
to its short half-life.
    In March 1999, DOE published the 1999 EIS, which addressed the 
production of tritium in the TVA's Watts Bar and Sequoyah nuclear 
reactors using TPBARs. The 1999 EIS assessed the potential 
environmental impacts of irradiating up to 3,400 TPBARs per reactor per 
fuel cycle (a fuel cycle lasts about 18 months). On May 14, 1999, DOE 
published the ROD for the 1999 EIS (64 FR 26369) in which it announced 
its decision to enter into an agreement with TVA to produce tritium in 
the Watts Bar Unit 1 reactor (Watts Bar 1) in Rhea County, Tennessee, 
near Spring City; and Sequoyah Units 1 and 2 reactors (Sequoyah 1 and 
2) in Hamilton County, Tennessee, near Soddy-Daisy. In 2002, TVA 
received license amendments from the U.S. Nuclear Regulatory Commission 
(NRC) to produce tritium in those reactors. Since 2003, TVA has been 
producing tritium for NNSA by irradiating TPBARs only in Watts Bar 1. 
After irradiation, NNSA transports the TPBARs to the Tritium Extraction 
Facility at the DOE Savannah River Site in South Carolina. NNSA's 
Interagency Agreement with TVA to irradiate TPBARs is in effect until 
November 30, 2035.
    During irradiation of TPBARs in a reactor, a small amount of 
tritium diffuses through the TPBAR cladding into the reactor coolant; 
this is called permeation. The 1999 EIS estimated that the permeation 
rate of tritium through the TPBAR cladding into the reactor coolant 
system would be less than or equal to 1 curie per TPBAR per year. Based 
on tritium production experience at Watts Bar 1, NNSA has determined 
that tritium permeation through the

[[Page 40686]]

cladding is about three to four times higher than this estimate; 
nevertheless, tritium releases to the environment have resulted in 
radiation exposures that are well below regulatory limits. To put this 
permeation rate into perspective, it represents less than 0.1 percent 
of the total tritium each TPBAR produces during irradiation. NNSA has 
prepared the CLWR SEIS to update the information provided in the 1999 
EIS to include: (1) The analysis of the potential environmental impacts 
from TPBAR irradiation based on a conservative estimate of the tritium 
permeation rate, (2) NNSA's revised estimate of the maximum number of 
TPBARs necessary to support the current and projected future tritium 
supply requirements, and (3) a maximum production scenario of 
irradiating 5,000 TPBARs every 18 months, which NNSA might require as a 
contingency capability.

Purpose and Need for Agency Action

    U.S. strategic nuclear systems are based on designs that use 
tritium gas. Because tritium decays at a rate of about 5.5 percent per 
year (i.e., every 12.3 years one-half of the tritium has decayed), 
periodic replacement is required as long as the U. S. relies on a 
nuclear deterrent. The nation, therefore, requires a reliable source of 
tritium to maintain its nuclear weapons stockpile. Since completion of 
the 1999 EIS, the projected need for tritium has decreased. Near-term 
tritium requirements are more likely to be met with the irradiation of 
2,500 TPBARs, but this does not exclude the possibility that various 
potential future events could necessitate increasing TPBAR irradiation, 
including but not limited to changes in the NNSA's requirements for 
tritium, or to compensate for a prolonged reactor outage. In any event, 
the exact number of TPBARs to be irradiated will be determined by both 
national security requirements and TVA reactor availability, with no 
more than a total of 5,000 TPBARs (no more than 2,500 TPBARs per 
reactor) irradiated during an 18-month cycle, an amount that does not 
exceed the scope of the CLWR SEIS analysis, or the 1999 EIS.
    Because NNSA continues to need tritium for nuclear weapons, NNSA's 
purpose and need for the production of tritium in CLWRs remains the 
same today as described in the 1999 EIS. However, current tritium 
requirements are less than they were in 1999. The observed higher-than-
expected tritium permeation rate has resulted in precautionary 
limitations on the number of TPBARs that the NRC has permitted TVA to 
irradiate in its reactors.\1\ As a result, TVA cannot currently 
irradiate enough TPBARs in its reactors to meet NNSA's projected future 
tritium production requirements. The CLWR SEIS supplements applicable 
environmental analyses in the 1999 EIS to analyze and evaluate the 
potential effects of the higher tritium permeation to inform decisions 
related to producing tritium quantities needed to meet national 
security requirements.
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    \1\ Because of the higher-than-previously-expected rate of 
permeation, TVA requested, and the NRC approved, a reduction in the 
number of TPBARs TVA can irradiate per fuel cycle.
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Alternatives Considered

    To supply tritium to meet stockpile requirements, NNSA could 
potentially use one or more of four TVA CLWR units at the Watts Bar and 
Sequoyah sites (two at each site). These include the units evaluated in 
the 1999 EIS as well as Watts Bar Unit 2 (Watts Bar 2) which is 
currently coming online. The SEIS evaluates the potential environmental 
impacts from TPBAR irradiation for seven alternatives:
    The No-Action Alternative is based on the analysis in the 1999 EIS, 
the Record of Decision for the 1999 EIS, and analyses for NRC license 
applications and license amendment actions. The 1999 EIS estimated a 
maximum of 3,400 curies of tritium released from any reactor in a given 
year. To stay within this maximum 3,400 curies, the SEIS No Action 
Alternative assumes a conservative release of 5 curies for each TPBAR 
annually, or a total of 680 TPBARs in any given reactor. This means 
that the No-Action Alternative assumes irradiation of up to a total of 
2,040 TPBARs every 18 months using the reactors identified in the 1999 
ROD (Watts Bar 1, Sequoyah 1, and Sequoyah 2) to keep permeation levels 
under currently approved NRC license and regulatory limits.
    Alternative 1 assumes TVA would irradiate up to a total of 2,500 
TPBARs every 18 months at the Watts Bar site and would not irradiate 
TPBARs for tritium production at the Sequoyah site.
    Alternative 2 assumes TVA would irradiate up to a total of 2,500 
TPBARs every 18 months at the Sequoyah site and would not irradiate 
TPBARs for tritium production at the Watts Bar site.
    Alternative 3 assumes TVA would irradiate up to a total of 2,500 
TPBARs every 18 months using both the Watts Bar and Sequoyah sites. 
This would provide NNSA and TVA the ability to supply requirements 
using either site independently or to use both sites, with each 
supplying a portion of the necessary tritium.
    Alternative 4 assumes TVA would irradiate up to a total of 5,000 
TPBARs every 18 months at the Watts Bar site using Watts Bar 1 and 2. 
Because TVA would irradiate a maximum of 2,500 TPBARs in any one 
reactor, this would involve use of both Watts Bar reactors. Under this 
alternative, TVA would not irradiate TPBARs for tritium production at 
the Sequoyah site.
    Alternative 5 assumes TVA would irradiate up to a total of 5,000 
TPBARs every 18 months at the Sequoyah site using Sequoyah 1 and 2. 
Because TVA would irradiate a maximum of 2,500 TPBARs in any one 
reactor, this would involve use of both Sequoyah reactors. Under this 
alternative, TVA would not irradiate TPBARs for tritium production at 
the Watts Bar site.
    Alternative 6 assumes TVA would irradiate up to a total of 5,000 
TPBARs every 18 months using both the Watts Bar and Sequoyah sites. 
Because TVA would irradiate a maximum of 2,500 TPBARs in any one 
reactor, this could involve the use of one or both reactors at each of 
the sites.
    The following table summarizes these alternatives and provides 
information about the number of TPBARs analyzed per site as well as the 
maximum number of TPBARs that could be irradiated every 18 months for 
each alternative. The maximum number of TPBARs analyzed in the CLWR 
SEIS for irradiation in a single reactor (as opposed to a single site) 
is 2,500 TPBARs per fuel cycle versus the 3,400 TPBARs analyzed in the 
1999 EIS.

                                                             Tritium Production Alternatives
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                                                                                      Alternatives
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             Site                      No-Action              1            2                 3                 4           5                 6
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                                Watts bar     Sequoyah    Watts bar    Sequoyah    Watts bar   Sequoyah    Watts bar   Sequoyah    Watts bar   Sequoyah
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Reactor Units................  1..........  1 and 2....  1 and/or 2.  1 and/or 2  1 and/or 2  1 and/or 2  1 and 2...  1 and 2...  1 and/or 2  1 and/or 2

[[Page 40687]]

 
Number of TPBARs analyzed per  680........  1,360......  2,500......  2,500.....  1,250.....  1,250.....  5,000.....  5,000.....  2,500.....  2,500
 site.
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Maximum TPBARs irradiated                2,040           2,500......  2,500.....           2,500          5,000.....  5,000.....           5,000
 every 18 months for
 alternative.
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    In the Notice of Intent to prepare the CLWR SEIS (76 FR 60017; 
September 28, 2011), NNSA stated that it would assess the impacts 
associated with tritium production in CLWRs based on a permeation rate 
of about 5 curies of tritium per TPBAR per year. Although the observed 
tritium permeation through the cladding has been less than 5 curies of 
tritium per TPBAR per year, the current permeation rate does not take 
into account potential uncertainties about operating cycle length, 
tritium production per TPBAR, and future operational changes that could 
occur at the TVA reactors, all of which could affect the permeation 
rate.
    Given these potential uncertainties in operational parameters, and 
after consultation with TVA and the Pacific Northwest National 
Laboratory (the TPBAR design agency), NNSA decided to evaluate an even 
higher and thus more conservative tritium permeation rate (10 curies of 
tritium per TPBAR per year) in the CLWR SEIS instead of 5 curies of 
tritium per TPBAR per year. NNSA, the Pacific Northwest National 
Laboratory, and TVA have determined that a tritium permeation rate of 
10 curies of tritium per TPBAR per year is the best estimate to ensure 
that the analyses would reasonably be expected to bound uncertainties 
in relation to future operations. By analyzing this higher tritium 
permeation rate, NNSA is confident that the SEIS provides a reasonable, 
but conservative and bounding, analysis of the potential environmental 
impacts from tritium production in the Watts Bar and Sequoyah reactors. 
In addition, the SEIS includes a standalone analysis of the potential 
impacts associated with a permeation rate of 5 curies of tritium per 
TPBAR per year for 2,500 TPBARs per 18-month cycle at Watts Bar 1 to 
provide the most realistic estimate of the potential impacts.

Preferred Alternative

    The Preferred Alternative is the alternative the agency believes 
would ensure its ability to fulfill its statutory mission, giving 
consideration to environmental, economic, technical, and other factors. 
In the Draft CLWR SEIS, NNSA identified Alternative 1 as the Preferred 
Alternative. While, as previously stated, the irradiation of 2,500 
TPBARs every 18 months is likely to meet near-term national security 
requirements, NNSA has determined that responsible planning needs to 
incorporate the flexibility to address potential future scenarios, 
including but not limited to a change in tritium production 
requirements or a prolonged reactor outage. Such events could require 
NNSA to increase the number of TPBARs that must be irradiated in a 
given 18-month period. To enable that flexibility, NNSA designated 
Alternative 6 as the Preferred Alternative in the Final SEIS, because 
that alternative encompasses the full numerical range of TPBARs that 
could, under any currently foreseeable circumstances, be irradiated in 
an 18-month period, at either or both the Watts Bar and Sequoyah sites, 
to satisfy national security requirements.

Environmentally Preferable Alternative

    After considering the potential impacts to each resource area by 
alternative, NNSA identified the No-Action Alternative as the 
environmentally preferable alternative. Under the No-Action 
Alternative, as many as 680 TPBARs would be irradiated every 18 months 
in each of the following reactors: Watts Bar 1, Sequoyah 1 and Sequoyah 
2. If all three reactors were used for tritium production, a maximum of 
2,040 TPBARs could be irradiated every 18 months. This is the lowest 
limiting value considered for the total number of TPBARs proposed to be 
irradiated under any of the alternatives and consequently would result 
in less potential environmental impact.

Environmental Impacts of Alternatives

    The CLWR SEIS analyzed the potential impacts of each alternative on 
land use, aesthetics, climate and air quality, geology and soils, water 
resources, biological resources, cultural resources, infrastructure and 
utilities, socioeconomics, and human health and safety. The CLWR SEIS 
also analyzed the potential environmental impacts of each alternative 
that may result from accidents and intentional destructive acts, 
transportation, and those associated with waste and spent nuclear fuel 
management, and environmental justice. The key SEIS findings are: (1) 
Tritium releases from normal operations with TPBAR irradiation would 
have an insignificant impact on the health of workers and the public; 
(2) tritium releases from TPBAR irradiation would increase tritium 
concentrations in the Tennessee River in comparison with not 
irradiating TPBARs; however, the tritium concentration at any drinking 
water intake would remain well below the maximum permissible 
Environmental Protection Agency (EPA) drinking water limit of 20,000 
picocuries per liter; (3) TPBAR irradiation would not have a 
significant adverse impact on the operation and safety of TVA reactor 
facilities, and the potential risks from accidents would remain 
essentially the same whether TPBARs were irradiated in a TVA reactor or 
not; and (4) irradiation of 2,500 TPBARs in a single reactor would 
increase spent nuclear fuel generation by about 24 percent per fuel 
cycle and irradiation of 5,000 TPBARs at a single site would increase 
spent nuclear fuel generation at either Watts Bar or Sequoyah by about 
48 percent per fuel cycle; however, TVA has an infrastructure in place 
and has a plan to manage the increased volume of spent nuclear fuel 
assemblies.
    The potential environmental impacts of each alternative are 
summarized for comparison in the Summary and Section 2.5 of the Final 
CLWR SEIS. Summary Table S-2 and Final CLWR SEIS Table 2-5 provide a 
summary of potential environmental impacts associated with the 
Preferred Alternative as well as a means for comparing the potential 
impacts of the Preferred Alterative with each of the analyzed 
alternatives.

Public Involvement

    NNSA published a Notice of Intent to prepare the CLWR SEIS in the 
Federal Register (76 FR 60017) on September 28, 2011, to invite 
comments and suggestions on the proposed scope of the CLWR SEIS. NNSA 
requested public comments by mail, facsimile, or email by the close of 
the scoping period on November 14, 2011. A public scoping

[[Page 40688]]

meeting took place on October 20, 2011, in Athens, Tennessee. NNSA 
considered all scoping comments it received in the preparation of the 
Draft CLWR SEIS.
    In August 2014, NNSA published the Draft CLWR SEIS. The 45-day 
public comment period on the Draft CLWR SEIS began on August 8, 2014, 
and ended on September 22, 2014. During the comment period, public 
hearings were held to allow the public to comment on the Draft CLWR 
SEIS in Athens, Tennessee, on September 9, 2014; and Chattanooga, 
Tennessee, on September 10, 2014. In addition, NNSA accepted public 
comments via mail, email, and facsimile. NNSA considered all comments 
received in the preparation of the Final CLWR SEIS.

Comments on the Final CLWR SEIS

    NNSA distributed the Final CLWR SEIS to Congressional members and 
committees; State and local governments; other Federal agencies, 
culturally affiliated American Indian tribal governments, non-
governmental organizations, and other stakeholders including members of 
the public who requested the document. Also, the Final CLWR SEIS was 
made available via the DOE and NNSA Web sites. On March 4, 2016, EPA 
issued the notice of availability (NOA) for the Final CLWR SEIS (81 FR 
11557). During the 30 days following publication of the NOA, NNSA 
received one comment letter from the EPA, dated April 4, 2016. The 
Appendix to this ROD identifies the comments contained in that letter 
and provides NNSA's responses. NNSA has concluded that those comments 
do not identify a need for further NEPA analysis.

Decision

    NNSA has decided to implement the Preferred Alternative, 
Alternative 6, which allows for the irradiation of a total of 5,000 
TPBARs every 18 months using both the Watts Bar and Sequoyah sites. 
Because TVA could irradiate a maximum of 2,500 TPBARs in any one 
reactor, one or both reactors at each of the sites could be used. For 
the analyses in the SEIS, NNSA assumed for Alternative 6 that each site 
would irradiate 2,500 TPBARs every 18 months. However, because the SEIS 
analyzes the impacts of irradiating up to 5,000 TPBARs at a single 
site, Alternative 6 is not intended to limit the number of TPBARs 
irradiated at either the Watts Bar or Sequoyah site, so long as no more 
than a total of 5,000 TPBARs is irradiated every 18 months, with no 
more than 2,500 TPBARs in any reactor core.

Basis for Decision

    The 1999 EIS discusses NNSA's purpose and need to produce tritium 
by irradiating TPBARS in one or more CLWRs. That purpose and need 
remains unchanged and is the foundation for the decision announced in 
this ROD. In making its decision, NNSA considered potential 
environmental impacts of operations and activities, current and future 
mission needs and compatibility, TVA missions and reactor licensing 
considerations, technical and security considerations, availability of 
resources, and public comments on the CLWR SEIS.
    The selection of Alternative 6 is based primarily on the increased 
flexibility that it affords to deal with currently unanticipated 
circumstances. With respect to potential human health and safety 
impacts, although irradiation of up to a maximum total of 5,000 TPBARs 
in an 18-month period will increase potential doses to workers and the 
public, all doses will be well within regulatory limits. The potential 
use of both the Watts Bar and Sequoyah sites provides both NNSA and TVA 
the greatest flexibility to meet future tritium production 
requirements, something the other alternatives do not provide. That is 
especially true now that four reactors (i.e., the addition of Watts Bar 
2) are potentially available to assist in meeting national security 
requirements.

Mitigation Measures

    To mitigate potential impacts from tritium releases, TVA would 
construct and operate a 500,000-gallon tritiated water tank system at 
Sequoyah in the event of a decision to irradiate TPBARs at that site or 
to facilitate routine tritium management. This system would be similar 
to that at the Watts Bar site. TVA would use the Watts Bar and Sequoyah 
tank systems to store tritiated water after it passed through the 
liquid radioactive waste processing system. TVA would release the 
stored tritiated water to the Tennessee River by the existing pathways. 
The tank systems that TVA currently has in place at the Watts Bar site 
and would potentially have in place at the Sequoyah site would have 
sufficient capacity to store and release the water to the Tennessee 
River at appropriate times (that is, TVA will release stored tritiated 
water from the tank during times of higher river flows for better 
dilution), and it will enable TVA to minimize the potential impacts of 
tritiated water releases. The systems would enable TVA to plan fewer 
releases each year and to ensure that site effluents would continue to 
remain well below regulatory concentration limits. Additionally, TVA 
will continue to monitor its operations for emissions to air and water 
in accordance with its NRC licensing requirements. Lastly, NNSA is 
continuing TPBAR research efforts, with the goal to reduce tritium 
permeation into the reactor coolant.

    Issued in Washington, DC, this 15th day of June, 2016.
Frank G. Klotz,
Under Secretary for Nuclear Security, Administrator, National Nuclear 
Security Administration.

Appendix: Comments Received on the Final CLWR SEIS

    NNSA received one comment letter on the Final CLWR SEIS. That 
letter, from the EPA dated April 4, 2016, contained comments on 
three topics which NNSA is addressing in this Appendix to the ROD.
    The first EPA comment was a recommendation that radiological and 
effluent monitoring should continue as the Project progresses. NNSA 
and TVA agree with this recommendation and note that TVA will 
continue to monitor its operations for emissions to air and water in 
accordance with its NRC licensing requirements.
    The second EPA comment was a recommendation that the Project 
Team continue to work closely with any affected communities, 
regulatory agencies, and other stakeholders as the Project 
progresses. The EPA specifically identified radiological and 
effluent monitoring, as well as spent nuclear fuel management, as 
issues relevant to such coordination. In response to this comment, 
the NNSA and TVA reiterate their commitment to closely coordinate 
with any potentially affected communities, regulatory agencies, and 
other stakeholders as the Project progresses. Notifications of 
notable Project activities will be posted on both TVA and NNSA 
public information Web sites, as appropriate, and all regulatory 
requirements will be met in an open and transparent manner. NNSA and 
TVA welcome public involvement as the Project progresses.
    The third EPA comment was a request that the ROD further 
evaluate the potential consequences of a breached holding tank 
releasing water containing tritium to the owner-controlled area and 
flowing to the Tennessee River. Such a scenario is addressed in the 
SEIS, in Section 1.6, with the conclusion that the EPA drinking 
water limit of 20,000 picocuries per liter would not be exceeded at 
the nearest community drinking water intake in the event of an 
instantaneous release of the maximum expected quantity of tritiated 
water in the tank. That conclusion is based on the assumption that 
the tritiated water would be reasonably well-mixed into the river by 
the time the flow reached the first community system drinking water 
intake.
    In that scenario, the impacts (doses from drinking water 
consumption) on an annual basis would be no different than currently 
evaluated in Chapter 4 of the SEIS. In addition, during the NRC 10 
CFR 50.59 regulatory process for the tank system, TVA analyzed the 
potential offsite dose that could

[[Page 40689]]

result from the rupture of the tank and the release of the entire 
contents of the tank to the Tennessee River without any holdup or 
dilution prior to entering the river. The results of that analysis 
indicated that the offsite dose due to liquid releases (water 
ingestion, fish ingestion, and recreation) would be less than 0.21 
millirem. Airborne offsite doses were calculated to be less than 1.5 
millirem. These doses are well below all regulatory limits.
    Design features and safety systems for the tritiated water tank 
system make such an instantaneous release/rupture unlikely. 
Specifically, the 500,000-gallon stainless steel tritiated water 
storage tank is set within a larger diameter open tank secondary 
containment structure to provide full capacity retention. A rain 
shield over the open containment tank connects to the primary tank 
above the usable level of the tank, providing a pathway into the 
secondary containment for all leaks on the side wall of the primary 
tank. The primary tank also includes an overflow line piped from 
beneath a top bladder to a 1000-gallon overflow storage tank located 
in the annulus between the primary and secondary tanks to contain 
overfills within the secondary tank. The bottoms of the tanks are 
separated with a mesh and any leakage between the two tank bottoms 
is directed to an alarmed sump inside the annulus area to provide 
leak detection. Piping outside of the tank is run inside a covered 
highway-rated concrete trench lined with epoxy and provided with a 
leak detection system.

[FR Doc. 2016-14775 Filed 6-21-16; 8:45 am]
 BILLING CODE 6450-01-P