[Federal Register Volume 66, Number 244 (Wednesday, December 19, 2001)]
[Notices]
[Pages 65516-65520]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-31218]
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NUCLEAR REGULATORY COMMISSION
[Docket No. 50-255]
Nuclear Management Company, LLC; Palisades Plant 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. DPR-20, held
by Nuclear Management Company, LLC (NMC or the licensee), for operation
of the Palisades Plant, located in Van Buren County, Michigan, and the
NRC is issuing this environmental assessment and finding of no
significant impact.
Environmental Assessment
Identification of the Proposed Action
The proposed amendment would change the limiting conditions for
operation (LCOs), surveillance requirements (SRs), and design features
in the Technical Specifications (TSs) to provide more flexible fuel
loading constraints for the Palisades fuel storage racks and
accommodate future core designs. The changes affect TS Sections 3.7.15,
``Spent Fuel Pool (SFP) Boron Concentration,'' 3.7.16, ``Spent Fuel
Assembly Storage,'' and 4.3, ``Design Features--Fuel Storage.'' Allowed
uranium enrichments for storage would be increased. Enrichment limits
for storage racks for unirradiated fuel (currently limited to fuel
assemblies having a maximum average planar uranium-235 (U-235)
enrichment of 4.20 weight percent) would be increased
[[Page 65517]]
to allow storage of 24 unirradiated fuel assemblies having a maximum
planar average U-235 enrichment of 4.95 weight percent, subject to
proposed loading pattern constraints (e.g., the center row being empty
if stored fuel exceeds 4.05 percent U-235 enrichments). Similarly, the
storage racks for unirradiated fuel could contain 36 unirradiated fuel
assemblies having a maximum planar average U-235 enrichment of 4.05
weight percent, subject to similar proposed loading pattern constraints
not necessarily requiring the center row to be empty. Region I storage
racks (currently limited to a maximum enrichment of 4.40 weight
percent) would be changed to allow storage of unirradiated or
irradiated fuel up to 4.95 weight percent enrichment on the basis of
revised criticality analyses that assume no credit for soluble boron in
the pool under normal conditions, but which take credit for 1350 ppm of
soluble boron under accident conditions. Enrichment requirements for
Region II fuel storage racks (currently limited to 3.27 weight percent)
would be changed to allow storage of unirradiated fuel up to 1.14
weight percent and irradiated fuel of equivalent reactivity up to 4.6
weight percent initial enrichment on the basis of criticality analyses
that take credit for 850 ppm of soluble boron in the pool under normal
conditions and 1350 ppm of soluble boron under accident conditions. The
TSs (e.g., proposed Table 3.7.16-1) for allowable enrichments for fuel
storage in Region II of the SFP or the north tilt pit would continue to
be based upon a combination of initial enrichment and burnup, but the
proposed change would also add decay time to this combination. The
existing limitations that Region I racks may contain only ``new or
partially spent'' fuel assemblies, and that Region II spent fuel racks
may contain only ``partially spent'' fuel assemblies, would be changed
to ``new or irradiated fuel assemblies which meet the initial
enrichment, burnup, and decay time requirements of [the proposed
revision to] Table 3.7.16-1.'' The existing requirements that fuel
assemblies in new or Region I fuel storage racks must contain ``216
rods which are either UO2,
Gd2O3UO2, or solid metal'' would be
deleted. TS 3.7.15 would continue to require that the SFP boron
concentration be equal to or greater than 1720 ppm whenever fuel is
stored in the spent fuel pool, and be verified weekly. However, the
optional Action Statement A.2.2 to immediately initiate action to
perform a SFP verification when the concentration is not within limits
would be deleted (as would a related portion of the applicability
statement regarding verification). The licensee also included changes
to the associated TS Bases.
The proposed action is in accordance with the application dated
March 2, 2001, as supplemented by letters dated March 29 and September
14, 2001. Although the initial application for a license amendment was
tendered by Consumers Energy Company (CEC), CEC has subsequently been
succeeded by NMC as the licensed operator of Palisades. By letter dated
May 17, 2001, NMC requested that the Commission continue to process and
disposition licensing actions previously docketed and requested by CEC.
The Need for the Proposed Action
The proposed action to change the fuel enrichment and burnup
combinations acceptable for storage in Region II racks is needed to
allow flexibility in fuel placement within the pool. This flexibility
is needed because recent fuel assembly enrichments at Palisades have
been above the current 3.27 weight percent enrichment limit for Region
II racks specified in TS 4.3.1.2. Thus, currently, these assemblies can
only be stored in Region I racks that have limited unused storage
capacity. This proposed action is also needed to eliminate reliance
upon programs (periodic ``blackness'' testing) designed to detect
degradation and ensure the integrity of fixed Boroflex poison material
in the Region II fuel racks for reactivity control. Since the
licensee's criticality calculations for this proposed change do not
credit the Boroflex material, periodic blackness testing can be
discontinued.
The proposed action to increase fuel storage enrichment limits
allows the licensee the flexibility to pursue increased reload fuel
enrichments needed to optimize fuel cycle costs.
Environmental Impacts of the Proposed Action
The NRC has completed its evaluation of the potential radiological
consequences for both normal and accident conditions associated with
the proposed allowed storage of fuel with increased enrichment and SFP
criticality calculations supporting the proposed changes. Radiological
consequences are only indirectly affected by increasing fuel
enrichment. The radiological consequences are primarily a function of
operating power and burnup. By increasing fuel enrichment, the same
power level can be produced for a longer period of time before
refueling. Therefore, the proposed allowed storage of fuel with
increased enrichment in the SFP would have no effect on authorized
operating power levels, but would result in increasing the burnup
levels that can be practically achieved. The proposed license amendment
to change the TSs would not affect the allowed maximum burnup for
Palisades. The licensee determines this limit using approved fuel
assembly and core design methodology stated in the Palisades Final
Safety Analysis Report (FSAR), as periodically updated. The evaluation
of the radiological consequences resulting from fuel handling accidents
(and other accident and transient conditions) would not change since
the maximum allowed fuel burnup remains unchanged. The licensee will
continue to evaluate reload core designs on a cycle-by-cycle basis as
part of its reload safety evaluation process to confirm that the cycle
core design adheres to the limits that exist in the accident analyses
and TSs and, thus, ensure that each reactor operating cycle will be
acceptable.
A. TS Changes Associated with the Fuel Pool in General
The applicability of TS LCO 3.7.15 would be changed from ``When
fuel assemblies are stored in the SFP and a verification of the stored
assemblies has not been performed'' to ``When fuel assemblies are
stored in the Spent Fuel Pool.'' The NRC staff finds this to be a more
restrictive change with no environmental impact.
Required Action A.2.2 for LCO 3.7.15 would be deleted because
verification alone would not restore the plant to analyzed conditions.
Required Action A.2.1 would be renumbered as ``A.2.''
The intent of the existing LCO 3.7.15 is to protect against
criticality during a fuel handling accident or misloading event. The
licensee's criticality analyses supporting the proposed action credit
boron for normal storage as well as for accident scenarios. Therefore,
the applicability of LCO 3.7.15 would be extended to all times when
fuel assemblies are stored in the Palisades fuel pool and Action A.2.2
would be eliminated.
The change in applicability effectively increases the minimum SRs
for spent fuel boron since samples now must be taken even if loading
has been verified. Since administrative procedures at Palisades
currently require these samples at least weekly, this change would have
no effect upon plant operations and would not result in a change to
individual or cumulative occupational radiation exposure limits.
Similarly, the changed surveillance
[[Page 65518]]
would not result in a change to radiological or nonradiological
effluent releases during normal or accident scenarios.
B. TS Changes Associated with the Storage Racks for Unirradiated Fuel
The enrichment allowed in TS 4.3.1.3.a would be changed from ``Fuel
assemblies having a maximum average planar U235 enrichment
of 4.20 weight percent'' to ``Twenty-four unirradiated fuel assemblies
having a maximum planar average U-235 enrichment of 4.95 weight
percent, and stored in accordance with the pattern shown in Figure
4.3.-1; or Thirty-six unirradiated fuel assemblies having a maximum
planar average U-235 enrichment of 4.05 weight percent, and stored in
accordance with the pattern shown in Figure. 4.3.-1.'' Existing TS
4.3.1.3.c would be deleted and existing TS 4.3.1.3d would be renumbered
as 4.3.1.3c.
Since the storage racks for new (unirradiated) fuel are not used to
store irradiated fuel, radiological consequences associated with
changes in storage limitations are largely limited by the prevention of
inadvertent criticality. The licensee's criticality analyses supporting
this license amendment request show that the keff based on a
95-percent probability at a 95-percent confidence level (i.e., the 95/
95 keff) for the new fuel storage rack is less than 0.95
assuming enrichment up to 4.05 weight percent U-235 when fully loaded
with 36 unirradiated assemblies. The analyses also show the 95/95
keff for the new fuel storage rack is less than 0.95 when
loaded with only 24 unirradiated assemblies with enrichment up to 4.95
weight percent U-235. The center row of the rack is left empty under
this configuration. The licensee provided a graphical description of
both loading patterns in Figure 3 of its engineering analysis, EA-SFP-
99-03 (Enclosure 2 to the March 2, 2001, supplemental letter), which
shows \1/2\ of the new fuel storage rack--the loading pattern continues
through the other half of the rack. The design-basis assembly is a 216-
pin Palisades assembly. The licensee found earlier assembly types with
fewer than 216 pins and guide tubes to be bounded since their
enrichment is less than or equal to 3.27 weight percent. The licensee
also notes that all assemblies with fewer than 216 pins have been
irradiated and, therefore, cannot be stored in the storage racks for
new fuel. Any new designs other than those assumed in the licensee's
calculation, including but not limited to different numbers of fueled
pins, different pellet diameters, and different pellet densities, would
first be evaluated by the licensee against the design-basis calculation
and in accordance with 10 CFR 50.59, ``Changes, Tests and
Experiments,'' before being stored in the racks. Therefore, the NRC
staff finds that the proposed TS changes associated with the racks for
storage of unirradiated fuel will not have a significant adverse
radiological impact.
Storage of higher enriched fresh fuel assemblies in the storage
racks for unirradiated fuel, under specific loading patterns, has no
effect on nonradiological effluent releases.
C. TS Changes Associated with Region I Fuel Pool Storage
The enrichment allowed in TS 4.3.1.1.a for fuel assemblies in
Region I fuel storage racks would be changed from ``having a maximum
enrichment of 4.40 weight percent'' to ``having a maximum planar
average U-235 enrichment of 4.95 weight percent.'' In TS 4.3.1.1.d, the
existing requirement that the Region I fuel storage racks be designed
and maintained with:
``New or partially spent fuel assemblies. Assemblies with enrichments
above 3.27 weight percent U235 must contain 216 rods which
are either UO2 , Gd2O3UO2,
or solid metal.''
would be changed to
``New or irradiated fuel assemblies.''
The licensee's criticality analyses supporting this license
amendment request show that the 95/95 keff for the Region I
fuel storage racks is less than 0.95 assuming the enrichment of an
assembly is less than or equal to 4.95 weight percent U-235. The
design-basis assembly is a 216-pin Palisades assembly. Earlier assembly
types with less than 216 pins and guide tubes are bounded since their
maximum enrichment is less than or equal to 3.27 weight percent. The
licensee states that the calculation bounds all assemblies currently
stored at Palisades and those the licensee foresees in the future. Any
new designs other than those assumed in the licensee's calculation,
including but not limited to different numbers of fueled pins,
different pellet diameters, and different pellet densities, will first
be evaluated by the licensee against the design-basis calculation
before being stored in the racks. In addition, before being used in the
Palisades core, any new fuel design is first evaluated as part of the
licensee's reload safety evaluation to ensure the cycle core design
adheres to the limits that exist in the accident analyses and TSs. The
licensee performs such analyses using approved methodologies as defined
in TS 5.6.5, ``Core Operating Limits Report (COLR),'' and in accordance
with 10 CFR 50.59.
In itself, increasing the enrichment level allowed for storage in
the Region I fuel pool racks has no effect on possible radiological or
nonradiological effluent releases. Since the licensee's criticality
design calculations show that Keff remains below 0.95 in all
normal storage and accident scenarios, there is no significant
increased threat of radiation exposure due to accidental criticality in
the fuel pool. If the licensee should decide to pursue reload
enrichments higher than the current storage limit (i.e., greater than
4.40 weight percent), the result would not adversely impact the
environmental effects since radiological impacts are only indirectly
affected by increasing fuel enrichment. The radiological impacts are
primarily a function of operating power and burnup. The purpose of
increased fuel enrichment is the ability to produce the same power
level for a longer period of time before refueling. Therefore, the
proposed allowed storage of fuel with increased enrichment in the SFP
would have no effect on authorized operating power levels, but would
result in increasing the burnup levels that can be practically
achieved. Again, licensees evaluate the use of fuel (at any enrichment
and burnup) on a cycle-by-cycle basis to ensure that parameters such as
assembly discharge burnups are within limits specified in the FSAR.
Therefore, the proposed TS changes associated with Region I fuel
pool storage have no significant adverse radiological impact. These
changes also have no adverse nonradiological impact.
D. TS Changes Associated with Region II Fuel Pool Storage
The licensee proposes the following TS changes regarding the
storage of fuel assemblies in Region II of the fuel pool:
LCO 3.7.16 currently requires that ``The combination of initial
enrichment and burnup of each fuel assembly stored in Region II shall
be within the requirements of Table 3.7.16-1.'' This would be changed
to require that ``The combination of initial enrichment, burnup, and
decay time of each irradiated fuel assembly stored in Region II shall
be within the requirements of Table 3.7.16-1.'' Thus, this change would
add the decay time of each assembly as an additional requirement for
storage in Region II. Similarly, the associated SR (SR 3.7.16.1) to
``Verify by administrative means that the initial enrichment and burnup
of each spent fuel assembly stored in Region II is in accordance with
Table 3.7.16-1'' would be changed to
[[Page 65519]]
``Verify by administrative means that the combination of initial
enrichment, burnup, and decay time of each irradiated fuel assembly
stored in Region II is in accordance with Table 3.7.16-1.'' Existing TS
Table 3.7.16-1 would be replaced by Table 4 from the licensee's
engineering analysis, EA-SFP-99-03, which specifies Region II burnup
requirements after various periods of decay. The existing requirement
of TS 4.3.1.2.a that the Region II fuel storage racks are designed and
shall be maintained with fuel assemblies ``having a maximum enrichment
of 3.27 weight percent'' would be changed to ``having a maximum planar
average U-235 enrichment of 4.60 weight percent.'' A new TS 4.3.1.2.b
would be added to require that the Region II fuel storage racks be
designed and maintained with ``Keff [less than] 1.0 if fully
flooded with unborated water, which includes allowances for
uncertainties as described in Section 9.11 of the FSAR.'' Existing TS
4.3.1.2.b would be renumbered as 4.3.1.2.c and revised to require that
Region II fuel storage racks be designed and maintained with
Keff less than or equal to 0.95 ``if fully flooded with
water borated to 850 ppm,'' rather than ``if fully flooded with
unborated water.'' Existing TSs 4.3.1.2.c and 4.3.1.2.d would be
renumbered 4.3.1.2.d and 4.3.1.2.e, respectively. TS 4.3.1.2.e (former
4.3.1.2.d) would also be changed to require that Region II fuel storage
racks be designed and maintained with ``[p]artially spent fuel
assemblies which meet the initial enrichment and burnup requirements of
Table 3.7.16-1,'' to ``[n]ew or irradiated fuel assemblies which meet
the initial enrichment, burnup, and decay time requirements of Table
3.7.16-1.'' A new figure based upon Figure 3 of the licensee's
engineering analysis, EA-SFP-99-03, and showing storage rack loading
patterns for new fuel would be added as TS Figure 4.3-1.
The licensee's criticality analyses, which are the basis for this
license amendment request, show that the 95/95 Keff for the
Region II fuel storage racks is less than 0.95 assuming the enrichment
of an assembly is less than or equal to 4.60 weight percent U-235 and
assuming 850 ppm boron in the pool water. The analyses also ensure that
Keff is less than 1.0 assuming no boron. The proposed
revision to Table 3.7.16-1 contains the burnup, enrichment, and decay
time combinations shown to be acceptable in the licensee's engineering
analysis, EA-SFP-99-03.
Boron is already present in the Palisades SFP. Likewise, the fuel
stored in the pool is burned to levels dictated by core design
constraints. Fuel assemblies experience radioactive decay while they
are stored. These characteristics of the fuel would not be changed by
the proposed amendment. Therefore, crediting the reactivity effects
associated with boron, burnup, and decay in the design-basis
criticality calculations has no effect upon possible radiological or
nonradiological effluent releases. Since the criticality design
calculations show that Keff remains below 0.95 in all normal
storage and accident scenarios, there is no increased threat of
radiation exposure due to accidental criticality in the fuel pool.
In general, the proposed burnup and enrichment combinations that
are acceptable for storage in the Region II racks require higher
burnups for a given enrichment than those present in the current TS
Table 3.7.16-1. This increase in allowed minimum burnup does not affect
radiological consequences since the actual fuel burnup is dictated by
core design constraints and may be significantly higher than that
required for storage in Region II fuel storage racks (up to 58,900 MWD/
MTU assembly average for recent Palisades reload fuel, as discussed in
FSAR Section 3.2.3, Nuclear Limits). In general, higher burnup has a
limited effect on the short-lived isotope inventory in the fuel due to
the development of an equilibrium condition between production and
decay. Instead, extended burnups increase the fraction of the short-
lived isotopes that migrate into the fuel-clad gap region (see, for
example, NUREG/CR-5009, ``Assessment of the Use of Extended Burnup Fuel
in Light Water Power Reactors,'' prepared for the U.S. Nuclear
Regulatory Commission by Pacific Northwest). With increasing burnup,
there is no decrease in fuel rod integrity or the probability of fuel
failures during normal operations, as long as actual burnup does not
exceed the vendor-approved values. However, with the increased short-
lived activity in the clad-gap region, increased burnup could result in
increased activity being released into the reactor coolant under normal
operation if fuel failures were to occur. Maximum fuel burnup limits
are not being changed by this proposed amendment.
E. Conclusions
On the basis of the above assessment, the NRC staff concludes that
the proposed TS changes regarding the storage of new and irradiated
fuel, including fuel with increased allowed enrichment (up to 4.95
weight percent), will not have a significant adverse environmental
effect.
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 off site, 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 nonradiological impacts, the proposed
action does not have a potential to affect any historic sites. It does
not affect nonradiological plant effluents and has no other
environmental impact. Therefore, there are no significant
nonradiological environmental impacts associated with the proposed
action
Accordingly, the NRC staff concludes that there are no significant
environmental impacts associated with the proposed action.
Environmental Impacts of the Alternatives to the Proposed Action
As an alternative to the proposed action, the NRC staff considered
denial of the proposed action (i.e., the ``no-action'' alternative).
Denial of the application would result in no change in current
environmental impacts. The environmental impacts of the proposed action
and the alternative action are similar.
Alternative Use of Resources
The action does not involve the use of any different resource than
those previously considered in the Final Environmental Statement for
Palisades dated June 1972, as supplemented.
Agencies and Persons Consulted
On December 12, 2001, the NRC staff consulted with the Michigan
State official, Mary Ann Elzerman, regarding the environmental impact
of the proposed action. The State official agreed with the NRC staff's
proposed issuance of this Environmental Assessment and Finding of No
Significant Impact.
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.
Further details with respect to the proposed action may be found in
the licensee's application dated March 2, 2001, as supplemented by
letters dated March 29 and September 14, 2001.
[[Page 65520]]
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 ADAMS Public Library
component on the NRC Web site, http://www.nrc.gov (the Public
Electronic Reading Room). 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 at [email protected].
For the Nuclear Regulatory Commission.
Dated at Rockville, Maryland, this 12th day of December, 2001.
Darl S. Hood,
Senior Project Manager, Section 1, Project Directorate III, Division of
Licensing Project Management, Office of Nuclear Reactor Regulation.
[FR Doc. 01-31218 Filed 12-18-01; 8:45 am]
BILLING CODE 7590-01-P