[Federal Register Volume 62, Number 70 (Friday, April 11, 1997)]
[Notices]
[Pages 17790-17794]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-9340]
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DEPARTMENT OF ENERGY
Savannah River Operations Office Interim Management of Nuclear
Materials at the Savannah River Site
AGENCY: Department of Energy.
ACTION: Supplemental record of decision and supplement analysis
determination.
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SUMMARY: The U.S. Department of Energy (DOE) prepared a final
environmental impact statement (EIS), ``Interim Management of Nuclear
Materials'' (DOE/EIS-0220, October 20, 1995), to assess the potential
environmental impacts of actions necessary to manage nuclear materials
at the Savannah River Site (SRS), Aiken, South Carolina, until
decisions on their ultimate disposition are made and implemented. Some
of the particular materials considered in the EIS could present
environmental, safety and health vulnerabilities in their current
storage condition.
On December 12, 1995, DOE issued a Record of Decision (ROD) and
Notice of Preferred Alternatives, 60 FR 65300 (December 19, 1995), on
the interim management of several categories of nuclear materials at
the SRS, including Taiwan Research Reactor (TRR) spent nuclear fuel
rods. DOE decided to stabilize 81 TRR spent fuel rods because the TRR
fuel had failed,1 presenting environmental, safety and
health vulnerabilities that should be corrected. At the time of this
decision, DOE stated that, if additional TRR spent fuel failed, DOE
would categorize the failed fuel as Candidates for Stabilization and
perform appropriate National Environmental Policy Act (NEPA) review and
evaluation for stabilization of the material.
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\1\ The term ``failed'' means that the cladding on the fuel has
been breached. The ROD, 60 Fed. Reg. 65300 (December 19, 1995),
stated that failed fuel is indicated by gas releases from a fuel
storage canister or visible failure of the cladding or canisters.
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On February 8, 1996, DOE issued a Supplemental ROD, 61 FR 6633
(February 21, 1996), for the stabilization of Mark-16 and Mark-22
fuels, and other aluminum-clad targets. On September 6, 1996, DOE
issued a second Supplemental ROD, 61 FR 48747 (September 13, 1996), for
the stabilization of plutonium-239 solutions, a neptunium-237 solution
and obsolete targets.
DOE has now further decided, because of health and safety
vulnerabilities, to stabilize the remaining TRR spent nuclear fuel
located in the Receiving Basin for Offsite Fuels (RBOF) at the SRS,
using the F-Canyon and FB-Line facilities. The TRR spent nuclear fuel
to be stabilized consists of the equivalent of 310 fuel rods (some of
the rods were fragmented due to conditions in Taiwan) in 62 aluminum
canisters stored underwater in RBOF. DOE has decided to stabilize the
TRR spent nuclear fuel because additional TRR spent fuel in at least
two of the canisters has failed, and DOE believes that the rest is
likely to exhibit signs of failure at unpredictable intervals in the
near future. All 62 canisters contain TRR fuel that was subjected to
the same poor storage conditions in Taiwan, and the same physical
stress due to transportation conditions during shipment from Taiwan to
SRS, creating a propensity for corrosion of the fuel elements'
cladding. Once the cladding has failed, the failure cannot be arrested,
even by the excellent water quality conditions in RBOF. Thus, fission
products will continue to be released into RBOF.
By stabilizing the TRR fuel, DOE is taking prudent management steps
to alleviate the environmental, safety and health vulnerabilities
associated with the continued wet storage and degradation of the TRR
spent fuel. DOE considered interim measures to improve storage
conditions, such as those described in the Interim Management of
Nuclear Materials (IMNM) EIS, but DOE believes that an alternate
storage arrangement that eliminates contact between the fuel and water
cannot be implemented in a timely manner. For example, dry storage
facilities being planned on an aggressive schedule for domestic and
foreign research reactor spent fuel will not be available until
approximately 2003. In contrast, DOE expects that stabilizing the fuel
by processing it in the F-Canyon and FB-Line facilities can be
accomplished in 6 to 12 months.
The plutonium separated by the stabilization process (about 15
kilograms) will be stored at the SRS in existing vaults and then in the
new Actinide Packaging and Storage Facility, when it becomes
operational, until DOE implements long-term storage and disposition
decisions on weapons usable forms of plutonium, which were published in
the ROD for the Storage and Disposition of Weapons-Usable Fissile
Material (62 FR 3014, January 21, 1997). A Departmental commitment to
prohibit the use of plutonium-239 and weapons-usable highly enriched
uranium separated and/or stabilized during the phaseout, shutdown, and
cleanout of weapons complex facilities for nuclear explosive purposes
was approved by the Secretary of Energy on December 20, 1994, and DOE
is considering options for placing this material under international
safeguards.
FOR FURTHER INFORMATION CONTACT: For further information on the interim
management of nuclear materials at the SRS or to receive a copy of the
final EIS, the initial ROD or the subsequent supplemental RODs contact:
Andrew R. Grainger, NEPA Compliance Officer, U.S. Department of Energy,
Savannah River Operations Office, P.O. Box 5031, Aiken, South Carolina
29804-5031, (800) 242-8259, Internet: [email protected]
For further information on the DOE NEPA process, contact: Carol M.
Borgstrom, Director, Office of NEPA Policy and Assistance, EH-42, U.S.
Department of Energy, 1000 Independence Avenue, SW., Washington, DC
20585, (202) 586-4600, or leave a message at (800) 472-2756.
SUPPLEMENTARY INFORMATION: DOE prepared a final environmental impact
statement (EIS), ``Interim Management of Nuclear Materials'' (DOE/EIS-
0220, October 20, 1995), to assess the potential environmental impacts
of actions necessary to manage nuclear materials at the SRS, Aiken,
South Carolina, until decisions on their ultimate disposition are made
and implemented. In the Interim Management of Nuclear Materials (IMNM)
EIS, DOE evaluated the impacts of several stabilization alternatives
and a ``No Action'' alternative for all Taiwan Research Reactor (TRR)
spent nuclear fuel in RBOF. The estimates of the potential impacts
included normal operations, waste generation, potential accidents, and
cumulative impacts. In each case, the potential impacts for each
stabilization alternative were estimated based on the entire SRS
inventory of TRR spent fuel, the equivalent of 391 spent fuel rods in
143 aluminum canisters. As a result, the potential impact of
stabilizing all the TRR spent fuel by processing the material in F-
Canyon and FB-Line, as well as the potential impacts from the other
alternatives, was analyzed and documented in the IMNM EIS.
DOE previously has issued three RODs based on the IMNM EIS,
regarding the stabilization of nuclear materials at the SRS. In the
first ROD, 60 Fed Reg 65300 (December 19, 1995), DOE determined, as
relevant here, that 81
[[Page 17791]]
failed TRR spent nuclear fuel rods (contained in 81 canisters) would be
stabilized by processing the material to a metal through F-Canyon and
FB-Line to address environmental, safety and health vulnerabilities. In
that ROD, DOE also determined that the remaining intact TRR fuel rods
would remain in interim wet storage in RBOF unless they failed. As
stated in the ROD, if DOE determined that additional fuel, targets, or
canisters have failed, as indicated by gas releases from a canister, or
visible failure of cladding or canisters, DOE would categorize those
materials as Candidates for Stabilization. The ROD further states that
DOE would perform the appropriate NEPA review and evaluation for the
stabilization of any additional materials in RBOF that may be
determined at a later date to have failed (e.g., Supplement Analysis).
Stabilization of the 81 canisters of failed TRR spent fuel is currently
being completed.
Two canisters of TRR fuel, previously believed to contain intact
fuel, are now releasing gas, and therefore have been categorized as
containing failed fuel. DOE believes that the remaining TRR spent fuel
is likely to fail at unpredictable times in the near future. All 62
canisters contain TRR fuel that was subjected to the same poor storage
conditions in Taiwan, and the same physical stress due to
transportation conditions during shipment from Taiwan to SRS, creating
a propensity for corrosion of the fuel elements' cladding. Once the
cladding has failed, the failure cannot be arrested, even by the
excellent water quality conditions in RBOF. Thus, fission products will
continue to be released into RBOF.
Interim Management of Nuclear Materials EIS
The IMNM EIS considered the interim management of certain nuclear
materials at the SRS. These materials included 143 canisters containing
TRR spent nuclear fuel rods that were stored in RBOF. The TRR spent
nuclear fuel rods are natural uranium metal clad in aluminum.
At the time the EIS was prepared, DOE knew the cladding on at least
81 of the fuel rods was failed as a result of storage conditions in
Taiwan. In about 1990, prior to shipping the TRR spent fuel to the
United States, the failed fuel was placed in aluminum canisters, one
failed fuel rod per canister. Each canister was then drained of any
water that entered the canister, filled with an inert gas, and sealed
so that water in the storage pool would not come into contact with the
failed fuel.
The 310 TRR fuel rods that were believed to be intact (i.e., those
that indicated no visible breach in the cladding) were placed in
aluminum canisters for handling and storage purposes. Five rods were
loaded in each of the canisters, for a total of 62 canisters. The
canisters were designed to be loaded from the side. The opening for
loading the rods extended almost the entire length of the canister, and
a cover was latched in place after loading was completed. The covers
(and the canisters) were designed with slots to allow water into the
canisters. The overpack canisters were designed to facilitate handling
and storage, not to prevent the contact of the fuel rods with storage
pool water.
The IMNM EIS evaluated the potential environmental impact of
several alternatives for stabilizing the failed TRR fuel. These
alternatives included processing the fuel to either a metal or oxide
form, placing the material in dry storage, processing the material for
vitrification at the Defense Waste Processing Facility, and
vitrification in F-Canyon. DOE also considered continued wet storage of
the material, i.e., the ``No Action'' alternative. DOE performed the
evaluation of the potential impacts of these alternatives, assuming all
the material--i.e., all 143 canisters of TRR spent fuel--would be
stabilized, although the proposed action involved only 81 canisters
(containing 81 failed fuel rods). A summary of the potential impacts
from the alternatives was presented in Table 2-12 of the IMNM EIS.
By mid-1995, DOE had determined that 16 (of the 81) canisters
containing failed TRR spent nuclear fuel had deteriorated to the point
that the canisters were releasing gas and, as a consequence,
radionuclides into the water of RBOF. DOE proposed the 81 canisters of
TRR spent fuel as Candidates for Stabilization because: the release of
hydrogen gas indicated that the canisters likely would not prevent
water from coming into contact with the failed fuel or prevent
radionuclides from being released into the storage pool; the presence
of hydrogen gas indicated fuel corrosion was occurring; and the failure
of any more canisters was certain to result in additional radionuclides
being released into RBOF, since once corrosion has begun, it cannot be
arrested. DOE also decided that the remaining 62 canisters of presumed
``intact'' TRR fuel should be considered stable for interim wet storage
over about the next ten years.
In a ROD issued on December 12, 1995, 60 FR 65300 (December 19,
1995), DOE decided to stabilize the 81 failed TRR spent fuel rods by
implementing the Processing to Metal alternative described and analyzed
in the IMNM EIS. In addition, DOE concluded that if, ``after removing *
* * failed TRR fuel * * * from RBOF, DOE determines that additional
fuel * * * or canisters have failed, as indicated by gas releases from
a canister, or visible failure of cladding or canisters, DOE would
categorize those materials as Candidates for Stabilization. DOE would
perform the appropriate * * * [NEPA] review and evaluation for the
stabilization of any additional materials in RBOF that may be
determined at a later date to have failed (e.g., a Supplement
Analysis).'' Id. At 60 FR 65313.
Environmental Impacts of Alternatives
In the IMNM EIS, DOE evaluated the impacts of several stabilization
alternatives (i.e., Processing to Metal, Processing to Oxide, Improving
Storage, Processing and Storage for Vitrification in the Defense Waste
Processing Facility, and Vitrification in F-Canyon) and a ``No Action''
alternative. For each alternative, the IMNM EIS estimated the potential
impacts of stabilizing all of the TRR spent nuclear fuel (both failed
fuel and that believed to be intact), including normal operations,
waste generation, potential accidents, and cumulative impacts. In each
case, the potential impacts for each stabilization alternative were
estimated based on the entire SRS inventory of TRR spent fuel. As a
result, the potential impact of stabilizing all the TRR spent fuel by
Processing to Metal, as well as the potential impacts from the other
alternatives, was analyzed and documented in the IMNM EIS.
Since discovering that additional TRR fuel has failed, DOE has re-
evaluated the stabilization alternatives in the IMNM EIS to ensure that
the analysis remains valid. In the IMNM EIS, DOE concluded that these
alternatives would take from four to nine years to implement completely
for the TRR spent nuclear fuel, while the preferred alternative of
processing TRR spent fuel to a metal could be implemented more quickly.
DOE believes that the estimates of time to implement TRR spent nuclear
fuel stabilization alternatives in the IMNM EIS are still accurate. DOE
expects that stabilization of the remaining TRR spent fuel in RBOF
could be completed in 6 to 12 months.
As part of its re-evaluation, DOE considered interim storage
methods that could be implemented in accordance with the No Action
alternative. Interim storage methods would involve canning the TRR
spent nuclear fuel in RBOF and placing the material back in wet
storage.
[[Page 17792]]
To assure safe storage of the TRR spent fuel, vacuum drying capability
would be needed in RBOF. High temperature treatment, e.g., heating to
200 deg.C, would also likely be required for failed TRR
fuel. Drying and heating would be necessary because water, beyond a
minimal amount, must be removed from the fuel to prevent continued
corrosion and gas generation that could create unpredictable and
unmonitored conditions inside the fuel storage container. The SRS does
not currently have the capability to either dry or heat-treat spent
fuel, and could not develop such a capability for several years.
Additionally, the technology to heat-treat uranium metal fuel with
failed cladding is undeveloped and requires research. DOE does not
believe that treatment and canning could be satisfactorily implemented
before stabilization by processing to a metal could be accomplished.
Continuing to store the fuel in RBOF is not desirable because it
would exacerbate the corrosion of the fuel and result in continued
releases of fission products and, eventually, metal and oxide particles
in the basin water. These releases would subject workers to unnecessary
radiation exposure and would present an environmental, safety and
health vulnerability. Therefore, continued storage would do nothing to
resolve current concerns regarding wet storage of TRR spent fuel.
Furthermore, it would not be practical to remove individual failed
rods from the TRR fuel canisters because no efficient method to
identify a failed fuel rod exists. An inspection of the cladding
surface of each and every rod through magnification or, more likely,
nondestructive testing would be required to identify the existence and
location of cladding penetration. Based on previous experience with
contaminated, but unirradiated, fuel, an inspection of this magnitude
could take a year to complete, and stabilization actions would still be
required for the failed TRR fuel. As a result, this method would not
resolve current concerns regarding TRR fuel corrosion.
Decision
In the 1995 ROD, 60 FR 65300 (December 19, 1995), DOE decided to
stabilize 81 TRR spent nuclear fuel rods by implementing the
``Processing to Metal'' alternative described in the IMNM EIS. DOE
stated that this alternative was selected for reasons similar to those
for the Mark-31 targets (a material very similar to the TRR spent
nuclear fuel). That is, by processing the TRR spent fuel to a metal,
the material could be stabilized earlier than under the other
alternatives, and four to nine years earlier than the environmentally
preferred alternative, i.e., Improving Storage. Further delay in
removing the fuel from wet storage would serve no practical purpose.
Other reasons for selecting Processing to Metal include the fact that
the selected stabilization alternative relies on existing operating
equipment and trained personnel, the technical uncertainty is low,
costs are well established, and the small amount of plutonium metal
produced would be a small fraction of the DOE inventory and would not
present nuclear nonproliferation concerns. DOE believes that the
reasons for choosing the Processing to Metal alternative for initial
failed TRR fuel still apply to the remaining TRR spent nuclear fuel.
DOE therefore has concluded that all the TRR spent nuclear fuel in
RBOF is ``at risk'' material. DOE bases its conclusion on the
following:
The poor TRR spent fuel use and storage conditions in
Taiwan are known to have caused gross failure for other TRR fuel;
The TRR fuel that DOE believed to be intact was exposed to
the same poor conditions in Taiwan;
Poor storage conditions facilitate the start of corrosion
sites on the spent fuel cladding;
The high quality of the RBOF storage basin water would not
be sufficient to arrest existing fuel corrosion because uranium metal
corrosion and existing corrosion sites established on aluminum would
continue to progress even with excellent water quality;
Hydrogen gas generation around TRR spent fuel, previously
believed to be intact, indicates that fuel cladding has failed and that
the uranium metal beneath the fuel cladding is corroding;
Water monitoring data indicate that storing the TRR spent
fuel in RBOF caused radioactivity releases into RBOF water to more than
double; and
The continued presence of fission products in the RBOF
pool water indicates that fuel failure is continuing.
Corrosion of the TRR fuel creates radiation exposure, safety, waste
and environmental concerns which dictate the expeditious resolution of
the corrosion problem. Continued wet storage would facilitate the TRR
fuel corrosion process. Other storage arrangements would be impractical
because of the protracted implementation schedule. Therefore, DOE has
decided to stabilize the TRR spent nuclear fuel in the 62 canisters by
the IMNM EIS Processing to Metal alternative using the F-Canyon and FB-
Line facilities at the SRS.
Issued at Washington, DC, April 2, 1997.
Alvin L. Alm,
Assistant Secretary for Environmental Management.
Supplement Analysis for Stabilization of TRR Fuel
Background
The U.S. Department of Energy (DOE) prepared a final environmental
impact statement (EIS), ``Interim Management of Nuclear Materials''
(DOE/EIS-0220, October 20, 1995), to assess the potential environmental
impacts of actions necessary to manage nuclear materials at the
Savannah River Site (SRS), Aiken, South Carolina, until decisions on
their ultimate disposition are made and implemented. Some of the
particular materials considered in the EIS could present environmental,
safety and health vulnerabilities in their current storage condition.
On December 12, 1995, DOE issued a Record of Decision (ROD) and
Notice of Preferred Alternatives, 60 FR 65300 (December 19, 1995), on
the interim management of several categories of nuclear materials at
the SRS, including Taiwan Research Reactor (TRR) spent nuclear fuel
rods. DOE decided to stabilize 81 TRR spent fuel rods because the TRR
fuel had failed,2 presenting environmental, safety and
health vulnerabilities that should be corrected. At the time of this
decision, DOE stated that, if additional TRR spent fuel failed, DOE
would categorize the failed fuel as Candidates for Stabilization and
perform appropriate National Environmental Policy Act (NEPA) review and
evaluation for stabilization of the material.
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\2\ The term ``failed'' means that the cladding on the fuel has
been breached. The ROD, 60 Fed. Reg. 65300 (December 19, 1995),
stated that failed fuel is indicated by gas releases from a fuel
storage canister or visible failure of the cladding or canisters.
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The IMNM EIS categorized 62 canisters of TRR spent nuclear fuel as
suitable for interim storage, based on the absence of obvious gas
generation or obvious damage to the fuel or the storage canisters.
However, no evaluation was conducted of the integrity of the fuel rods
within the canisters. Instead, DOE relied on the results of inspections
completed prior to shipping the fuel to the United States for
classifying the fuel as intact.
TRR fuel failure in Taiwan was the result of poor reactor
operations or poor storage and handling conditions. For example, some
TRR fuel was stored in outdoor dry storage consisting of a concrete pad
into which carbon steel cylinders were vertically inserted below
[[Page 17793]]
grade. TRR spent fuel rods, held in metal baskets, were lowered into
the cylinders. The cylinders were then capped and welded closed. Over
time, water intruded into the cylinders and severely damaged some of
the fuel. Failed cladding on TRR spent fuel was common, and some of the
rods were so damaged that they had literally disintegrated into rubble.
Prior to loading all the TRR spent fuel for shipment to the United
States, the Nuclear Assurance Corporation (NAC) evaluated the fuel to
determine its integrity. NAC first visually inspected each rod to
detect cladding failures on the rods which are approximately one inch
in diameter and 10 feet long. NAC conducted its visual inspection from
a safe distance of at least 10 feet, using magnification devices such
as binoculars. Any failed fuel detected in this fashion was canned
immediately.
If no obvious defects were discovered, NAC then subjected each rod
to a ``sip'' test. For this test, a fuel rod was first placed in a
container filled with water. A sample of the water in the container was
drawn and analyzed to detect fission products such as cesium-137. After
three or four hours, another sample was drawn and analyzed. If the
difference between the two samples was greater than two times the
background radiation level, NAC considered the rod to be failed. Any
failed fuel detected in this fashion was canned, one failed fuel rod
per canister.
Rods that passed the visual and ``sip'' inspections were placed in
an aluminum ``overpack'' canister about 5 inches in diameter and 11
feet long. Five intact rods were placed in one canister. There were no
baffles or separators installed to provide any cushion between the rods
during shipment. The canisters were loaded in dry shipping casks for
the 12,000 mile trip to the SRS. During shipment, the fuel rods were
subjected to physical stress, such as impact between the rods in each
canister,3 due to transportation conditions. The TRR fuel
was shipped to the United States during 1990 and 1991.
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\3\ Spent fuel from foreign research reactors currently being
returned to the United States is shipped in an entirely different
manner that does not allow the fuel rods to come into direct contact
with one another or contribute in any other way to their
degradation.
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Upon receipt at the SRS, the transportation casks were placed
underwater in RBOF. The canisters were unloaded from the transportation
casks, and a visual inspection of the canisters' exterior was performed
prior to placing the canisters in underwater storage in RBOF.
The results of the tests on TRR spent fuel integrity that were
performed in Taiwan only provided an assessment of the TRR fuel rods at
the time they were loaded into the canisters. The tests could not
predict cladding performance after the canisters were loaded into the
shipping casks, or after six to seven years of wet storage at the SRS,
especially in light of the historically poor storage and handling
conditions in Taiwan.
Current Conditions
The Westinghouse Savannah River Company (WSRC), DOE's management
and operating contractor at the SRS, has observed occasional gas
bubbles coming from the locations in RBOF where the TRR fuel previously
believed to be intact is stored. Until recently, the source of the gas
bubbles was not specifically identified because gas generation was
sporadic. When the TRR fuel canisters were placed in storage in 1990
and 1991, DOE was planning to reprocess the TRR spent fuel, and
therefore did not expect the fuel to remain in wet storage for a
prolonged period. However, in 1992, the Secretary of Energy decided to
phase out reprocessing activities, and consequently the TRR fuel has
remained in wet storage much longer than anticipated.
In November 1996, WSRC noted a marked increase in the gas
generation rate from two of the canisters containing TRR fuel that was
previously thought to be intact. Gas bubbles that previously appeared
on a sporadic basis appeared on a continuous basis at intervals ranging
from about every 40 seconds to 1 minute. The likely reason for the
increase in the generation of gas bubbles from the two TRR fuel
canisters is that corrosion of either the fuel cladding or the uranium
metal fuel is accelerating. DOE believes that corrosion sites on the
TRR spent fuel occurred as a result of damage during handling, or poor
storage conditions in Taiwan or in transit to the SRS. Pre-existing
corrosion sites on the fuel cladding would have continued to progress
after the material was placed in RBOF, because once a corrosion site
had been formed, corrosion would continue despite the excellent water
quality in RBOF.
Corrosion of uranium metal clad in aluminum was studied extensively
for the Mark-31 targets that were stored in the L-Reactor Disassembly
Basin.4 These targets, which have recently been dissolved
for stabilization, were very similar in nature to the TRR spent nuclear
fuel in that both consisted of uranium-238 metal clad with aluminum.
WSRC reported that the typical corrosion phenomenon occurred in two
phases: an initiation stage, corresponding with the penetration of the
fuel cladding either by corrosion or by storage and handling damage,
followed by the beginning of uranium corrosion; and a propagation
stage, corresponding with a significant growth of the corrosion's
extent. The first stage was usually of unpredictable duration. During
that stage, deformation of the cladding did not usually occur, but
occasional bubbles of hydrogen could evolve. The reaction involved:
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\4\ J.P. Howell, ``Corrosion Surveillance in Spent Fuel Storage
Pools,'' NACE Corrosion/97 paper 107 (Houston, Texas: National
Association of Corrosion Engineers, 1997).
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U+2H2OUO2+2H2
The second phase, that is, the propagation phase, was characterized
by growth of a blister at the location of cladding penetration. Once
swelling started, the blister grew at a fairly steady rate until the
accumulated uranium oxide caused the cladding to split. After the
cladding split, the uranium oxide was released into the water, and a
larger area of uranium metal was exposed to attack. In either phase,
the progression of uranium metal corrosion would continue to occur
regardless of the basin water quality. In sum, once the uranium metal
is exposed to water, a more rapid reaction takes place liberating
hydrogen, and once that corrosive process has started, there is no
practical way to stop the process as long as the fuel is in contact
with water.
The increase in the generation of gas bubbles from TRR fuel
canisters is an indication that corrosion of the fuel is progressing
from the initiation stage to the propagation stage. As this process
continues, uranium oxide production will cause the cladding to split
and expose more uranium metal to the basin water. As the corrosion
products form, they will continue to carry radionuclides into the
storage basin water. Canisters that display only occasional bubbles
contain fuel that is earlier in the initiation stage of corrosion. In
any case, the presence of hydrogen gas provides a strong indication
that uranium metal corrosion has been initiated in the TRR fuel.
Another indication of corroding fuel is the release of fission
products into the RBOF water. The basin filtration system removes
fission products to maintain radioactivity levels in the water at
acceptable limits, but this system must be turned off on a periodic
basis for maintenance. During these periods, the rate of radioactivity
release has been determined by establishing the rate of
[[Page 17794]]
change in the basin radioactivity levels. Currently, a steady increase
in basin radioactivity levels always follows shutdown of the RBOF
filtration system. This increase is due to the constant release of
fission products by failed fuel in the basin. DOE believes that the
source of this radioactivity is the TRR fuel, because the average RBOF
water radioactivity levels more than doubled when the TRR spent fuel
was placed in storage in the early 1990s.
Environmental Analysis
The CEQ regulations for implementing NEPA, 40 CFR 1502.9(c), direct
federal agencies to prepare a supplement to an EIS when an agency
``makes substantial changes in the proposed action that are relevant to
environmental concerns, or there are significant new circumstances or
information relevant to environmental concerns and bearing on the
proposed action or its impacts.'' The DOE regulations for compliance
with NEPA, 10 CFR 1021.314, direct that when it is unclear whether or
not a supplemental EIS is required, the Department is to prepare a
supplement analysis.
This Supplement Analysis (Analysis) evaluates new information
regarding the condition of TRR spent fuel. In addition, this Analysis
compares this new information with the IMNM EIS' evaluation of failed
TRR spent fuel.
In the IMNM EIS, DOE evaluated the impacts of several stabilization
alternatives (i.e., Processing to Metal, Processing to Oxide, Improving
Storage, Processing and Storage for Vitrification in the Defense Waste
Processing Facility, and Vitrification in F-Canyon) and a ``No Action''
alternative. For each alternative, the IMNM EIS estimated the potential
impacts of stabilizing all of the TRR spent nuclear fuel (both failed
fuel and that believed to be intact), including normal operations,
waste generation, potential accidents, and cumulative impacts. In each
case, the potential impacts for each stabilization alternative were
estimated based on the entire SRS inventory of TRR spent fuel. As a
result, the potential impact of stabilizing all the TRR spent fuel by
Processing to Metal, as well as the potential impacts from the other
alternatives, was analyzed and documented in the IMNM EIS.
Since discovering that additional TRR fuel has failed, DOE has re-
evaluated the stabilization alternatives in the IMNM EIS to ensure that
the analysis remains valid. In the IMNM EIS, DOE concluded that these
alternatives would take from four to nine years to implement completely
for the TRR spent nuclear fuel, while the preferred alternative of
processing TRR spent fuel to a metal could be implemented more quickly.
DOE believes that the estimates of time to implement TRR spent nuclear
fuel stabilization alternatives in the IMNM EIS are still accurate. DOE
expects that stabilization of the remaining TRR spent fuel in RBOF
could be completed in 6 to 12 months.
Conclusion
Based on the foregoing, DOE finds that stabilizing the TRR fuel by
the Processing to Metal alternative in the IMNM EIS will result in
neither significantly greater environmental impacts than analyzed in
the IMNM EIS nor a substantial change in the proposed action relevant
to environmental concerns. Stabilizing all the TRR fuel by processing
it to a metal is consistent with the goals of the proposed action in
the IMNM EIS. Furthermore, stabilizing all the TRR fuel by processing
it to a metal is consistent with the stabilization action selected in
the December 12, 1995, ROD, which clearly allowed for the stabilization
of additional TRR spent fuel. Consequently, DOE has concluded that the
stabilization of the remaining TRR fuel does not require the
preparation of a supplemental EIS.
[FR Doc. 97-9340 Filed 4-10-97; 8:45 am]
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