[Federal Register Volume 63, Number 98 (Thursday, May 21, 1998)]
[Notices]
[Pages 28013-28014]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-13504]
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NUCLEAR REGULATORY COMMISSION
[Docket No. 50-397]
Washington Public Power Supply System, Nuclear Project No. 2
(WNP-2); Environmental Assessment and Finding of No Significant Impact
The U.S. Nuclear Regulatory Commission (the Commission) is
considering issuance of an amendment to Facility Operating License No.
NPF-21 issued to Washington Public Power Supply System (the licensee),
for operation of WNP-2 located in Benton County, Washington.
Environmental Assessment
Identification of the Proposed Action
The proposed action would revise the maximum yield strength for
emergency core cooling system suction strainer materials listed in the
WNP-2 Final Safety Analysis Report (FSAR).
The proposed action is in accordance with the licensee's
application for amendment dated April 16, 1998, as supplemented by
letters dated April 28 and May 8, 1998.
[[Page 28014]]
The Need for the Proposed Action
The proposed action is needed to support the progression to startup
for WNP-2, which is currently in a refueling outage. During this outage
newly designed suction strainers have been installed in the suppression
pool. They are designed to protect ECCS pumps from fibrous or other
material that could be transported to the suppression pool after a
design basis accident such as a loss of coolant accident. The licensee
determined after fabrication of these strainers that the stanless steel
material had measured yield strength which exceeded the limit which was
specified in the FSAR. Excessive yield strength can make the stainless
steel susceptible to stress corrosion cracking (SCC) under certain
environmental conditions. The licensee identified this as an unreviewed
safety issue and submitted an amendment request which would change the
yield strength for the installed strainers. Approval of this amendment
will enable the licensee to change reactor mode and declare the
strainers operable while progressing to startup and full power
operation.
Environmental Impacts of the Proposed Action
The Commission has completed its evaluation of the proposed action
and, based on the testing and analytical information provided by the
licensee, concludes that the increase in yield strength for the
specific material used in the suction strainers is acceptable. The
licensee has an effective cleanup system for the suppression pool,
which maintains a desired level of water cleanliness sufficient to
avoid conditions that would support SCC. Further, the licensee has
conducted a fracture mechanics analysis and has determined that
cracking in the surface martensitic structure of the strainers will not
propagate to a critical size and, thus, not jeopardize the strainers'
safety related function of protecting the ECCS pumps and spray nozzles.
Also, the licensee's analysis has demonstrated that the strainers have
adequate structural integrity to preclude failure when the forces of
design basis hydrodynamic loads are applied. Lastly, a Strauss test
using actual strainer material samples demonstrated acceptable stress
corrosion cracking resistance.
The staff has concluded that this change will not increase the
probability or consequences of accidents, no changes are being made in
the types of any effluents that may be released offsite, and there is
no significant increase in the allowable offsite or occupational
radiation exposure. Accordingly, the Commission concludes that there
are no significant radiological environmental impacts associated with
the proposed action.
With regard to potential nonradiological impacts, the proposed
action does not affect nonradiological plant effluents and has no other
environmental impact.
Accordingly, the Commission concludes that there are no significant
environmental impacts associated with the proposed action.
Alternatives to the Proposed Action
Since the Commission has concluded there is no significant
environmental impact associated with the proposed action, any
alternatives with equal or greater environmental impact need not be
evaluated. As an alternative to the proposed action, the staff
considered denial of the proposed action. 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 for WNP-2.
Agencies and Persons Consulted
In accordance with its stated policy, on May 13, 1998, the staff
consulted with the Washington State official, Mr. R. Cowley of the
Department of Health, State of Washington Energy Facility Site
Evaluation Council, regarding the environmental impact of the proposed
action. The State official had no comments.
Finding of No Significant Impact
Based upon 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 letter dated April 16, 1998, as supplemented by letters
dated April 28, 1998, and May 8, 1998, which are available for public
inspection at the Commission's Public Document Room, The Gelman
Building, 2120 L Street, NW., Washington, DC, and at the local public
document room located at the Richmond Public Library, 955 Northgate
Street, Richland, Washington 99352.
Dated at Rockville, MD., this 14th day of May 1998.
For the Nuclear Regulatory Commission.
Chester Poslusny,
Senior Project Manager, Project Directorate IV-2, Division of Reactor
Projects--III/IV, Office of Nuclear Reactor Regulation.
[FR Doc. 98-13504 Filed 5-20-98; 8:45 am]
BILLING CODE 7590-01-P
