[Federal Register Volume 67, Number 165 (Monday, August 26, 2002)]
[Notices]
[Pages 54826-54828]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-21644]


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NUCLEAR REGULATORY COMMISSION

[Docket No. 50-390]


Tennessee Valley Authority, Watts Bar Nuclear Plant, Unit 1; 
Environmental Assessment and Finding of No Significant Impact

    The U.S. Nuclear Regulatory Commission (NRC) is considering 
issuance of an amendment to Facility Operating License No. NPF-90 held 
by the Tennessee Valley Authority (TVA or the licensee) for operation 
of the Watts Bar Nuclear Plant (WBN), Unit 1, located in Rhea County, 
Tennessee. Therefore, as required by Title 10, Code of Federal 
Regulations (10 CFR), Sec. 51.21, the NRC is issuing this environmental 
assessment and finding of no significant impact.

Environmental Assessment

Identification of the Proposed Action

    The proposed action would change WBN's Technical Specifications to 
allow TVA to irradiate up to 2304 tritium-producing burnable absorber 
rods (TPBARs) in WBN's reactor core. Irradiating the TPBARs in the 
reactor core supports the U.S. Department of Energy (DOE) in 
maintaining the nation's tritium inventory. TVA will insert the TPBARs 
into positions in the reactor core where conventional burnable poison 
rods would normally be (poison rods contain boron which reacts with 
neutrons making them unavailable for interacting with uranium atoms, 
thereby slowing fission and heat generation). TPBARs are not reactor 
fuel and do not generate thermal energy for generating electrical 
energy.
    TPBARs use lithium rather than boron. Neutron irradiation in the 
reactor core converts the lithium in the TPBARs into tritium. After one 
operating cycle, TVA would remove the fuel assemblies containing TPBARs 
from the WBN core and put them into the spent fuel pool. TVA would, 
after several weeks (based on plant schedules rather than decay 
considerations), remove the irradiated TPBARs from the fuel assemblies 
and consolidate them into shipping casks for DOE to transport to its 
tritium extraction facility at its Savannah River Site.
    The proposed action is in accordance with the licensee's 
application of August 20, 2001, as supplemented by letters of October 
29, November 14, November 21, December 7, December 19, 2001, and 
January 14, February 19, February 21, May 21, May 23, and July 30, 
2002.

The Need for the Proposed Action

    The proposed action would allow WBN to provide irradiation services 
for DOE to maintain the nation's tritium supply as prescribed by Public 
Law (Pub. L.) 106-65. Section 3134 of PL 106-65 directs the Secretary 
of Energy to produce new tritium at TVA's Watts Bar power plant.

Environmental Impacts of the Proposed Action

    DOE's Environmental Impact Statement, DOE/EIS-0288, Final 
Environmental Impact Statement (EIS) for the Production of Tritium in a 
Commercial Light Water Reactor, dated March 1999, assessed the 
environmental impacts of producing tritium at WBN. TVA was a 
cooperating Federal agency in preparing this EIS and adopted the EIS in 
accordance with 40 CFR 1506.3(c) of the Council on Environmental 
Quality regulations. DOE also prepared a Tritium Production Core (TPC) 
Topical Report, NDP-98-181, Rev. 1, to address the safety and licensing 
issues associated with incorporating TPBARs in a reference pressurized-
water reactor. The NRC used its Standard Review Plan (NUREG-0800) as 
the basis for evaluating the impact of the TPBARs on a reference plant. 
The NRC reviewed the TPC Topical Report and issued a Safety Evaluation 
Report, NUREG-1672, in May 1999. NUREG-1672 identified 17 plant-
specific interface issues that a licensee would have to address in 
support of a plant specific amendment to operate a tritium production 
core. TVA's application of August 20, 2001, and supplements, addressed 
these interface issues. NRC staff is reviewing TVA's amendment request 
and will issue a safety evaluation documenting its review.
1. Radiological Impact from Tritium Release to the Reactor Coolant 
System (RCS) Under Normal Plant Operations with 2304 TPBARs in the Core
    Tritium levels in the RCSs of large pressurized-water reactors have 
ranged as high as 4000 curies per year (Ci/yr) without exceeding 
regulatory limits. TVA estimated, as discussed in its May 23, 2002, 
letter, that the tritium level in the RCS at WBN would increase from 
about 1826 Ci/yr to 3170 Ci/yr with 2304 TPBARs in the reactor. This 
increased tritium level could increase overall occupational exposure, 
but NRC data summarized in NUREG-0713, ``Occupational Radiation 
Exposure at Commercial Nuclear Power Reactors and Other Facilities,'' 
dated 1995, indicate tritium exposure is not an important contributor 
to overall occupational exposure.
    TVA stated that WBN does not expect this increased activity to 
affect normal RCS feed-and-bleed operation throughout the cycle, as 
discussed in its May 23, 2002, letter. The NRC staff finds no reason to 
disagree with TVA's conclusion. Thus, primary coolant discharge volumes 
should be similar to current volumes.
    The staff concludes that the additional dose rate from operating 
WBN with 2304 TPBARs in the reactor will not have a significant impact 
on TVA's ability to control worker radiation doses and keep them well 
within regulatory limits using the controls and practices in WBN's 
existing Radiation Protection Program.
    If increased RCS feed and bleed is required, it may be necessary to 
temporarily store the increased volume of tritiated liquid onsite, or 
to dilute the tritiated liquid to ensure that 10 CFR part 20 discharge 
limits are met. WBN has sufficient storage tanks to accommodate this 
additional liquid waste.
2. Radiological Impact from Liquid Effluents Under Normal Plant 
Operations with 2304 TPBARs in the Core
    The WBN facility has waste-treatment systems designed to collect 
and process waste that may contain radioactive material. The tritium in 
liquid effluents from WBN is diluted to a relatively low

[[Page 54827]]

concentration before it reaches even the most highly exposed members of 
the public. TVA's submittal of May 23, 2002, shows that the total 
additional dose to the maximally-exposed members of the public within 
50 miles of WBN from tritium in liquid effluents is estimated to be 
0.01 millirem per year (mrem/yr). This total dose, considering the 
minimal increase from tritium production, is less than 1.0 percent of 
the NRC 3-mrem/yr guideline for effluent exposure to the public. The 
staff concludes that the potential radiological impact on plant 
workers, members of the public, and the environment from operation with 
the TPC complies with all regulatory dose limits.
3. Radiological Impact from Radioactive Gaseous Emissions Under Normal 
Plant Operations with 2304 TPBARs in the Core
    A portion of the tritium might be released to the atmosphere. The 
amount would depend on plant conditions and the manner in which TVA 
operates WBN. Individuals could be exposed to tritium in a variety of 
pathways if it was released to the atmosphere. These pathways include 
inhalation and skin absorption, as well as consumption of meat, 
vegetables and milk. According to TVA, in its submittal of May 23, 
2002, the calculated tritium dose to the most highly-exposed members of 
the public through all pathways would be about 63 percent of the NRC 
annual exposure guideline for airborne effluents.
4. Radiological Impact from Solid Radioactive Waste Under Normal Plant 
Operations with 2304 TPBARs in the Core
    Irradiation of TPBARs is expected to increase the number of curies 
and volume of solid radioactive waste, primarily because of disposal 
(offsite) of the associated base plates and thimble plugs, which become 
irradiated. The estimated increase in activity inventory is from 
approximately 1800 Ci/year to approximately 3500 Ci/yr. The estimated 
increase in volume is from 32,820 cubic feet/year to 32,853 cubic feet/
year. The estimated resultant total worker dose resulting from handling 
the increased solid waste is approximately 1.1 percent of the dose 
assessment estimate of record. Offsite shipment and disposal would be 
in accordance with established agreements between TVA and DOE.
5. Radiological Impact to Workers in the Fuel Storage Area Under Normal 
Plant Operations with 2304 TPBARs in the Core
    The proposed amendment is not expected to significantly affect the 
doses to the workers in the fuel storage area. The TPBARs are designed 
to have minimal effect on plant operations, including refueling 
operations. Unirradiated TPBARs will produce no increase in exposure, 
occupational or public, because they are essentially non-radioactive. 
Possible increases in tritium airborne activity may increase dose to 
workers handling and consolidating radioactive TPBARs. However, TVA 
stated, in its submittal of May 23, 2002, that WBN's station dose 
assessment of record bounds the expected increase.
6. Non-Radiological Impact with 2304 TPBARs in the Core
    The proposal does not affect non-radiological plant effluents. The 
proposal does not result in any significant changes to land use or 
water use. It also does not result in any significant changes to the 
quantity or quality of effluents, and no effects on endangered or 
threatened species or on their habitat are expected. Therefore, no 
changes in, or different types of, non-radiological environmental 
impacts are expected as a result of the amendment.
7. Radiological Impact from Postulated Accidents with 2304 TPBARs in 
the Core
    TVA's submittal of May 23, 2002, discussed the effects of TPBARs on 
the possible consequences of the following postulated accidents 
discussed in WBN's Updated Final Safety Analysis Report (UFSAR):
     Fuel-handling accident
     Design basis loss-of-coolant accident (LOCA)
     Main steamline failure outside of containment
     Steam generator tube rupture
     Loss of normal alternating current power to plant 
auxiliaries
     Waste gas decay tank failure
     Rod ejection accident
     Failure of small lines carrying primary coolant outside 
containment
    Discussions of the postulated accidents with the greatest 
radiological consequences appear below.

a. Fuel-Handling Accident

    This accident is defined as dropping a spent fuel assembly 
containing irradiated TPBARs resulting in rupture of the cladding on 
all the fuel rods. TVA's calculations conservatively assumed that 24 
TPBARs (the maximum possible number) are in the dropped spent fuel 
assembly and that they all rupture and transfer their tritium to the 
spent fuel pool. Releasing this activity to the (1) control room 
boundary, (2) Exclusion Area Boundary over 2 hours, and (3) Low 
Population Zone over 30 days results in the doses to the thyroid, skin 
(beta), whole body (gamma), and Total Effective Dose Equivalent (TEDE), 
as defined in 10 CFR part 20, that are small percentages of regulatory 
limits.

b. LOCA

    This accident is defined as losing reactor coolant at a rate in 
excess of the capability of the reactor coolant makeup system. LOCAs 
could occur from breaks in pipes in the reactor coolant pressure 
boundary up to and including a break equivalent in size to the double-
ended rupture of the largest pipe in the RCS. TVA conservatively 
assumed that the entire tritium content of the 2304 TPBARs is released 
into containment during a postulated LOCA. Releasing this activity to 
the (1) control room boundary, (2) Exclusion Area Boundary over 2 
hours, and (3) Low Population Zone over 30 days results in doses to the 
thyroid, skin (beta), whole body (gamma), and TEDE that are small 
percentages of regulatory limits.
8. Post-LOCA Hydrogen Generation Inside Containment
    TVA's submittal of August 20, 2001, stated that TPBARs could 
release additional hydrogen to the containment following a large-break 
LOCA (LBLOCA). WBN has emergency operating procedures in place to start 
a hydrogen recombiner train when the containment volumetric percentage 
of hydrogen reaches 3 percent. Previous analysis for a conventional 
(non-TPBAR) core in the WBN UFSAR indicated that for an LBLOCA, with no 
recombiners started, the containment hydrogen concentration reached 
3.75 percent 4 days following event initiation. With additional 
hydrogen from the TPBARs, TVA's analysis indicated that the containment 
hydrogen concentration would only slightly increase 2 days following 
event initiation. If one recombiner train is started 24 hours after 
event initiation for the TPBAR core, the peak containment hydrogen 
concentration is limited to less than 4 percent for up to 6 days. 
Having up to 24 hours to place a recombiner train in service to 
maintain the containment hydrogen concentration below 4 percent is 
adequate in satisfying NRC Regulatory Guide 1.7. Accordingly, reactor 
operation with the TPBARs will not be a significant contributor to the 
post-LOCA hydrogen inventory, and will not

[[Page 54828]]

have a significant impact on the total hydrogen concentration within 
the containment when compared to the values associated with the non-
TPBAR core. The maximum containment hydrogen concentration can be 
maintained at less than the lower flammability limit of 4.0-volume-
percent, with one recombiner train started at a 3-percent hydrogen 
concentration approximately 24 hours after an LBLOCA.

Summary

    The Commission has completed its evaluation of the proposed action. 
The proposed action will not significantly increase the probability or 
consequences of accidents, no changes are being made in the types of 
effluents that may be released offsite, and there is no significant 
increase in occupational or public radiation exposure. Therefore, there 
are no significant radiological environmental impacts associated with 
the proposed action.
    With regard to potential non-radiological impacts, the proposed 
action does not have a potential to affect historic sites. It does not 
affect non-radiological plant effluents and has no other environmental 
impact. Therefore, there are no significant nonradiological 
environmental impacts associated with the proposed action.

Environmental Impacts of the Alternatives to the Proposed Action

    As an alternative to the proposed action, the staff considered 
denial of the proposed action (i.e., the ``no-action'' alternative). 
Denial of the application would result in no significant change in 
current environmental impacts. However, because there are no 
significant environmental impacts associated with this action, and 
because Pub. L. 106-65 directs that DOE produce tritium at WBN or the 
Sequoyah Nuclear Plant, this is not considered a viable option.

Alternative Use of Resources

    DOE evaluated the action, including completing construction of one 
or both of the Bellefonte Nuclear Plant Units and construction of an 
accelerator facility at the Savannah River site and concluded that the 
proposed alternative has the least environmental impact of the options 
considered. The NRC has no reason to disagree with DOE's decision.

Agencies and Persons Consulted

    On August 15, 2002, the staff consulted with the Tennessee State 
official, Debra Schults of the Tennessee Bureau of Radiological Health, 
regarding the environmental impact of the proposed action. The State 
official had no comments.

Finding of No Significant Impact

    On the basis of the environmental assessment, the NRC concludes 
that the proposed action will not have a significant effect on the 
quality of the human environment. Accordingly, the NRC has determined 
not to prepare an environmental impact statement for the proposed 
action.
    For further details with respect to the proposed action, see the 
licensee's letter dated August 20, 2001, as supplemented by letters 
dated October 29, November 14, November 21, December 7, December 19, 
2001, and January 14, February 19, February 21, May 21, May 23, and 
July 30, 2002. Documents may be examined, and/or copied for a fee, at 
the NRC's Public Document Room (PDR), located at One White Flint North, 
11555 Rockville Pike (first floor), Rockville, Maryland. Publicly 
available records will be accessible electronically from the Agencywide 
Documents Access and Management System (ADAMS) Public Electronic 
Reading Room on the internet at the NRC Web site, http://www.nrc.gov/reading-rm/adams.html. Persons who do not have access to ADAMS or who 
encounter problems in accessing the documents located in ADAMS, should 
contact the NRC PDR Reference staff by telephone at 1-800-397-4209 or 
301-415-4737, or by e-mail to [email protected].

    Dated at Rockville, Maryland, this 20th day of August, 2002.
    For the Nuclear Regulatory Commission,
L. Mark Padovan,
Project Manager, Section 2, Project Directorate II, Division of 
Licensing Project Management, Office of Nuclear Reactor Regulation.
[FR Doc. 02-21644 Filed 8-23-02; 8:45 am]
BILLING CODE 7590-01-P