ML20136H839
| ML20136H839 | |
| Person / Time | |
|---|---|
| Site: | River Bend  |
| Issue date: | 08/12/1985 |
| From: | Novak T Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20136H844 | List: |
| References | |
| NUDOCS 8508200522 | |
| Download: ML20136H839 (5) | |
Text
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UNITED STATES NUCLEAR REGULATORY C0m lSSION GULF STATES UTILITIES COMPANY 1
DOCKET NO. 50-458 f
f i
ENVIRONMENTAL ASSESSMENT AND FINDING OF NO SIGNIFICANT IMPACT The U. S. Nuclear Regulatory Commission (the Commission) is issuing i
exemptions from certain requirements of 10 CFR Part 50 to the Gulf States Utilities Company (the applicant) for the River Bend Station. Unit 1 facility i
i located in West Feliciana Parish, Louisiana.
i ENVIRONMENTAL ASSESSMENT A.
Control Panel 1EN8*PNLO4A 7
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Identification of the Proposed Action:
i The exemption would allow a delay in the completion of the seismic l
qualification of control panel 1EN8*PNLO4A. This schedular exemption from the j
requirements of General Design Criteria 2. " Design Bases For Protection Against I
j Natural Phenomena" would require completion of the seismic qualification of the control panel prior to exceeding 5 percent of rated power. The exemption is in 1
l accordance with the applicant's request dated August 12, 1985.
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The Need for the Proposed Action:
f The exemption is required to facilitate fuel loading and the continued i
i progress of preoperational and startup testing programs.
i Environmental Impacts of the Proposed Action:
The 125v de control panel IE:4*PNLO4A is located in the Control Building and provides control power to the 4.2 kV IE switchgear IENS*SWG1A, the 480v load centers IEJS*LDCIA and IEJS*LDC2A, and the 125v de switchgear IENB*SWG01A.
i The 125v de control panel is required to support equipment necessary for the
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shutdown of the plant.
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The environmental impact with respect to this exemption is related i
solely to the potential increased probability of a failure of this panel during and following a seismic event. However, the potential increase of the probability of a release of a significant amount of radioactive material i
resulting from the exemption being granted is small. During low power opera-tion, fission product inventories and decay heat generation rates are much lower than at full power so much more time is available to respond to abnonnal l
events. Moreover, the applicant stated in their letter of August 7,1985 that the 125v de control panel, IEN8*PNLO4A, is similar to equipment already seismically qualified for use at River Bend Station. The overall weight of the subject panel is $75 lb versus 875 lb for the qualified panel. The differences between the two i
panels are so minor that there is sufficient confidence about the seismic capability of the subject panel.
Alternative to the Proposed Action:
j Because the staff has concluded that there is no measurable environmental l
impact associated with the proposed exemption, any alternative to this exemption will have either no environmental impact or greater environmental impact.
1 The principal alternative would be to deny the requested exemption. This l
would not reduce the environmental impacts of plant operations and would result i
in unwarranted delays in power ascension.
B.
Air Operated Valves (1 DFR*A0V144 and 145) for Pool Pumpback System Identification of proposed Action:
l The exemption would allow a delay in the replacement of the operators of i
valves IDFR*A0V144 and IDFR*A0V145 in the suppression pool pumpback systen i
l (SPPS). This schedular exemption from the requirements of General Design Criteria 2 " Design Bases For Protection Against Natural Phenomena" would require replacement 1 -
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of the operators of these valves with qualified operators prior to exceeding 5 percent of rated power. The exemption is in accordance with the applicant's 1
request dated August 12, 1985.
j 1
The Need For the Proposed Action l
The exemption is required to facilitate fuel loading and the continued progress of preoperational and startup testing programs.
Environmental Impacts of the Proposed Action:
1DFR*A0V144 and IDFR*A0V145 are air-operated valves in a recently installed suppression pool pumpback system (SPPS).
Installation of the SPPS (which returns water which may have leaked through an unisolable passive failure from l
the suppression pool) incluces replacement of non-safety related sump pumps and i
j the operators of these valves with safety-related components. The pumps have t
)
been replaced and provided with a Class IE power supply. However, the operators i
of these valves have not yet been replaced. The operators have been ordered and I
l-will be installed prior to operation above 5 percent of full rated power.
Following a seismic event and the passive failure which leaks from the suppression 4
pool, these valves can be manually operated to provide the SPPS function within i
l 30 minutes. Following a LOCA and the passive failure which leaks from the sup-i j
pression pool, the solenoid which controls the air supply to the operator say fail.
In the event these valves fail to close (the fail-safe position) the water from the auxiliary building floor drain sump would be pumped to the radweste system instead of the suppression pool. The only event which would require that this i
water be pumped to the suppression pool would be an Emergency Core Cooling i
System (ECCS) line break in the cresent area. The probability of an ECCS pipe break in this area for the short time prior to exceeding 5 percent of i
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4 rated power is very small. Furthennore an accident occurring below 5 percent of rated power which would require the use of the suppression pool would i
require less suppression pool water than the design basis accident. Therefore i
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the probability in the event of an ECCS pipe break in the cresent area con-4 current with an accident requiring suppression pool water is extremely small.
j!
Alternative to the Proposed Action l
Because the staff has concluded that there is no measurable environmental 1
impact associated with the proposed exemption, any alternative to this exemption will have either no environmental impact or greater environmental impact.
The principal alternative would be to deny the requested exemption. This would not reduce the environmental impacts of plant operation and would result in unwarranted delays in power ascension.
4 ALTERNATIVE USE OF RESOURCES:
I These actions of the granting of the exemptions A and 8 discussed above do not involve the use of resources not previously considered in connection with i
j the " Final Environmental Statement Related to the Operation of River Bend Station" dated January 1985.
l AGENCIES AND PERSONS CONSULTED:
l f
The NRC staff reviewed the applicant's requests that support the above i
requested exemptions. The NRC staff did not consult other agencies or persons.
4 i
FINDING OF NO SIGNIFICANT IMPACT I
l The Commiission has determined not to prepare an environmental impact statement for the requested exemptions.
Based upon the foregoing environmental assessment, we conclude that the I
requested actions will not have a significant effect on the quality of the I
human environment.
i
. For further details with respect to this action, see the requests for the exemptions as listed herein, which are available for public inspection at the Commission's Public Document Room 1717 H Street, N. W., Washington, D. C.,
20555 and at the Government Documents Department, Louisiana State University, Baton Rouge, Louisiana.
Dated at Bethesda, Maryland, this 12th day of August 1985.
FOR THE NUCLEAR REGULATORY C0fMISSION Thomas M. Novak, Ass s irecter for Licensing Division of Licensing Office of Nuclear Reactor Regulation 1
._._.