[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]
BILLING CODE 6450-01-P