[Federal Register Volume 64, Number 66 (Wednesday, April 7, 1999)]
[Notices]
[Pages 17019-17021]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-8598]
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NUCLEAR REGULATORY COMMISSION
Carolina Power & Light Company; H. B. Robinson Steam Electric
Plant, Unit No. 2 Environmental Assessment and Finding of No
Significant Impact
Docket No. 50-261
The U.S. Nuclear Regulatory Commission (the Commission) is
considering issuance of an amendment to Facility Operating License DPR-
23 issued to Carolina Power and Light Company (the licensee) for
operation of the H. B. Robinson Steam Electric Plant (HBRSEP), Unit 2,
located at the licensee's site in Darlington County, South Carolina.
Environmental Assessment
Identification of the Proposed Action
The proposed action would amend the Facility Operating License to
reflect a revision to the HBRSEP Updated Final Safety Analysis Report
(UFSAR) to include the evaluation of a previously unanalyzed spent fuel
cask drop scenario. The analysis also considered a second scenario of
potential damage by lateral movement of the cask into plant equipment
that results in damage to the valves while shipping with the valve
covers removed. The cask drop scenario is hypothesized to occur during
movement of spent fuel shipping cask model IF-300, without the cask
valve covers installed, from the decontamination facility at the HBRSEP
to the shipping railcar using a crane in a non-single-failure-proof
configuration, i.e. using a non-redundant cask lifting yoke. The
maximum potential height from which the cask could be dropped during
the time of transfer with a non-redundant cask lifting yoke is 30 feet.
The postulated accident associated with lateral movement of the cask
could occur anytime during the general handling of the cask without the
cask valve covers installed. The proposed action is in accordance with
the licensee's request for NRC review dated August 28, 1997, as
supplemented by letters dated June 17, 1998, October 29, 1998, and
February 11, 1999.
The Need for the Proposed Action
At HBRSEP, Unit No. 2, loaded Spent Fuel Shipping Casks are shipped
by rail
[[Page 17020]]
to CP&L's Shearon Harris Nuclear Power Plant (SHNPP), where the fuel is
placed in long-term storage in the SHNPP spent fuel pool. With the cask
valve covers installed the IF-300 shipping cask is designed to
withstand being dropped from 30 feet onto an unyielding surface. The
current Certificate of Compliance (CoC) for the IF-300 cask requires
the valve box covers be fully installed. However, during a portion of
the overall cask handling process, CP&L is constrained in its movement
of this cask. The cask cannot be transferred by crane in the single-
failure-proof configuration from the railcar to the cask
decontamination area of the Fuel Handling Building (FHB) or returned to
the railcar because the redundant lifting yoke cannot fit onto the cask
while the cask is on the railcar. The maximum height of the cask while
being lifted with a non-redundant yoke is 30 feet. The valve box covers
must be removed to provide access to the valves for off-gas venting
from the cask. Because the FHB cask decontamination area cannot
accommodate installation or removal of the valve box covers, the covers
are removed at the rail car and remain off the cask during all
movements in the FHB. Lateral movement of the cask into plant equipment
with the valve covers removed or a cask drop while the cask is being
transferred using a non-redundant lifting yoke could result in damage
to the valves, resulting in a release of noble gas and iodine gap
activity to the environment. These scenarios create the possibility of
a new or different kind of accident not previously evaluated. The
consequences of the cask drop scenario would bound any consequences due
to impact during lateral movement. For all of the above reasons, there
is a need for a revision to the HBRSEP UFSAR to include the evaluation
of a previously unanalyzed spent fuel cask drop scenario to allow the
licensee to ship spent fuel using fuel handling procedures that are not
currently within the plant's licensing basis.
Environmental Impacts of the Proposed Action
An evaluation has been performed by the licensee to determine the
consequences of a postulated 30 foot cask drop accident with less than
full integrity, i.e, with the valve box covers removed. The evaluation
determined that, while the fuel components would be retained in the
cask, the vent/drain valves may be damaged and thus not be gastight.
Using the maximum activity loading for the IF-300 cask, this type of
release has been evaluated and the whole body and thyroid doses which
could result are a small fraction of those previously analyzed for the
fuel handling accident in Section 15.7.3 of the UFSAR. The personnel
involved in a cleanup after a postulated accident would need to
decontaminate a maximum of one cubic foot of material with a dose rate
of up to 10 rem/hr at one meter based on the limit established for the
maximum allowable water remaining in the cask after loading operations.
Personnel exposure rates could be effectively limited by use of
temporary shielding and remote handling tools. The release of activity
would not be sufficient to initiate the Control Room radiation alarm or
pressurization mode of the Control Room ventilation system. The
postulated dose to a Control Room occupant was calculated to be 3.5E-03
rem (whole body) and 7.8E-04 rem (thyroid). Dose assessments were
performed using maximum potential releases assuming failure of the
spent fuel within the cask and radionuclide release from damage to the
valves. Calculated doses at the site boundary were 0.0072 rem (whole
body) and 0.1233 rem (thyroid). This evaluation also concluded that it
will also bound any consequences of the damage due to an impact during
a lateral movement, since the dose risks would be a fraction of the
consequences of cask drop with less than full integrity.
These results have been, in part, independently verified by the NRC
staff. The NRC staff also reviewed the assumptions and methods of
analysis in the licensee's radiological consequence analysis to ensure
they are conservative, bounding, and consistent with the HBRSEP design
basis. Based on the above evaluation, the staff concludes that the
licensee has demonstrated with reasonable assurance that maximum
radiological consequences of dropping an IF-300 cask at the HBRSEP are
radiation doses to members of public that are a small fraction of the
numerical criteria in 10 CFR Part 100 and are well within the
acceptance criteria in the Standard Review Plan and, therefore, are
acceptable. The Commission has completed its evaluation of the proposed
action and concludes that there will be an insignificant increase in
environmental impact on the dose consequences of a spent fuel cask drop
with this change in shipping configuration.
The proposed action will not increase the probability or
consequences of accidents previously analyzed. No changes are being
made in the types of any effluents that may be released off-site and
there is no significant radiological environmental impacts associated
with the proposed action.
With regard to potential nonradiological impacts, the proposed
action does not involve 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 Commission concludes that there are no significant
environmental impacts associated with the proposed action.
Alternatives to the Proposed Action
The Spent Fuel Shipping Cask cannot be lifted in the single
failure-proof configuration from the cask decontamination area of the
FHB to the railcar with this configuration because the redundant
lifting yoke cannot fit onto the cask while the cask is on the railcar.
Therefore, alternatives to the proposed activity were considered which
include (1) designing a new redundant lifting rig and modifying the
shipping cask to allow the Spent Fuel Cask Crane to fit onto the cask
while the cask is situated on the railcar; (2) modifying the FHB to
accommodate installing the valve box covers on the Spent Fuel Shipping
Cask in the cask decontamination area before movement of the cask to
the railcar; or (3) ceasing spent fuel shipping operations and loading
the spent fuel into Independent Spent Fuel Storage Installation (ISFSI)
canisters. For the purposes of this review, the alternatives to the
proposed action have been evaluated using the dollar value per Person-
Rem of $2000 recommended by NUREG-1530, ``Reassessment of NRC's Dollar
Per Person-Rem Conversion Factor Policy.'' Since the postulated
consequences at the Site Boundary have been calculated to be 0.0072
Rem, the proposed change to the UFSAR can be assigned a value of
approximately $15 per person. From the HBRSEP, Unit No. 2 Emergency
Plan, the most populous 90 deg. sector out to 10 miles contained a
population of 23,210. Therefore, a dollar value of $350,000 was used
for comparison of the proposed activity with its alternatives.
Development of a redundant yoke and modification of the Spent Fuel
Cask Crane will involve the design, fabrication, and installation of a
one-of-a-kind redundant yoke that can be used for lifts of the Spent
Fuel Shipping Cask that include lifting of the cask to the railcar.
Modifying the FHB to accommodate installation of the valve box covers
prior to lifting the Spent Fuel Shipping Cask from the cask
[[Page 17021]]
decontamination area to the railcar would involve a major modification
to the unit to enclose a larger cask decontamination area within a
controlled air space. It is difficult to provide accurate estimates for
the cost of these alternatives because of the numerous variables
involved. It is believed that the cost for either of these alternatives
will be in excess of $1,000,000.
As an alternative to the proposed amendment, the staff considered
denial of the requested amendment; thus, shipment of spent fuel to
SHNPP could be terminated. The result of termination of spent fuel
shipment would be to require the storage of additional spent fuel
onsite until all existing capacity is used or additional capacity is
added to allow continued operation until the termination of the HBRSEP,
Unit No. 2, operating license on July 31, 2010. The Spent Fuel Pit has
already been reracked with high density fuel storage racks, and the
addition of storage capacity to the Spent Fuel Pit by further re-
racking is not feasible. CP&L maintains an ISFSI license for 8 ISFSI
canisters currently containing 56 spent fuel assemblies. No additional
capacity is available under the current ISFSI license. The license
could be amended to allow additional capacity using a new canister
design, or a canister licensed under a general license could be used.
The estimated cost of adding sufficient ISFSI storage capacity to
permit operation of the unit until the end of the current operating
license has been estimated to be approximately $5,000,000.
The action proposed by the licensee of performing the cask lifting
operations between the decontamination facility and the railcar with
the valve covers removed and using a non-redundant cask lifting yoke
has no significant impact on the environment either from routine
operations or from a postulated accident in this configuration. The
postulated accident dose is only a small fraction of 10 CFR Part 100
limits and within the acceptance criteria of the Standard Review Plan.
Therefore, the benefits of the proposed activity substantially outweigh
the costs of the alternatives to the proposed activity. 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
This action does not involve the use of any resources not
previously considered in the ``Final Environmental Statement Related to
the Operation of H.B. Robinson.''
Agencies and Persons Consulted
In accordance with its stated policy, on February 17, 1999, the
staff consulted with the South Carolina State official, Virgil Autry,
South Carolina Department of Health, Bureau of Radiological Health and
Environmental Control. The State official had no comments.
Finding of No Significant Impact
On the basis of the environmental assessment, the Commission
concludes that the proposed action will not have a significant effect
on the quality of the human environment. Accordingly, the Commission
has determined not to prepare an environmental impact statement for the
proposed action.
For further details with respect to the proposed action, see the
licensee's letters dated August 28, 1997, June 17, 1998, October 29,
1998, and February 11, 1999, which are available for public inspection
at the Commission's Public Document Room, which is located at The
Gelman Building, 2120 L Street, NW., Washington, DC, and at the local
public document room located at the Hartsville Memorial Library, 147
West College, Hartsville, South Carolina 29550.
Dated at Rockville, Maryland, this 31st day of March 1999.
For the Nuclear Regulatory Commission.
Sheri R. Peterson,
Section Chief, Project Directorate II/Section II-2, Division of
Licensing Project Management, Office of Nuclear Reactor Regulation.
[FR Doc. 99-8598 Filed 4-6-99; 8:45 am]
BILLING CODE 7590-01-P
