ML20236Q933
| ML20236Q933 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 11/13/1987 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20236Q929 | List: |
| References | |
| NUDOCS 8711200367 | |
| Download: ML20236Q933 (2) | |
Text
'
UNITED STATES g
g g
NUCLEAR REGULATORY COMMISSION 5
- l WASHINGTON, D. C. 20555 t
c
%..s /
i 1
SAFETYEVALUATIONBYTHEOFFICEOFNUCLEARREACTORREGULATIpN RELATED T0 AMENDMENT NO.118 TO FACILITY OPERATING LICENSE NO. DPR-66 DUQUESNE LIGHT COMPANY OHIO EDISON COMPANY PENNSYLVANIA POWER C'OMPANY BEAVER VALLEY POWER STATION, UNIT NO. 1 DOCKET NO. 50-334
1.0 INTRODUCTION
L In a letter dated April 22, 1985 (S. A. Varga to J. J. Carey) we notified the I
licensee (Duquesne Light Company) that the overtemperature AT response time as specified in the Technical Specifications may not appropriately reflect that assuaed in the FSAR, The licensee agreed with our assessment in a= letter I
dated June 11, 1985.' By letter dated January' 14, 1986, the dicensee fonnally 1
i submitted a change request. Our evaluation of the proposed change is 1
contained in the following 1:ection.
The staff's Inspection Report 50-334/85-20 described the licensee's j
3 repl6 cement of the original Sostman resistance temperature detectors (RTDs) l with Rosemount RTDs. The response times of these two models of RTDs are diff'e rent. The original FSAX analysis addressed both model RTDs, and hence j
the replacement of one model with the other does not result in need for a i
l regnalysis.
(,
However, after all Sostman RTDs have been replaced with Resemount' RTDs, the
?
unit experienced numerous AT alams (see details'in the referenced Inspection Report). The licensee modified wiring of the react,orTrotection system to
, address the problem, and submitted corresponding l proposed Technical Specification changes in its January 14, 1986 letter. ' By letter dated July 25, i
1986 the licensee made a revision to clarify the original submittal.
a As a result of our September 23, 1986 request for additional infonnation,. the a
L licensee provided a response in the form of Westinghouse' Topical Reports WCAP-11462 (Proprietary) and VCAP-11463 (non-proprietary), both entitled "Overtemperature and Overppr Delta-T Reactor Trip Setpoint Calculations
~
for Beaver Valley Unit 1 (Letter,:. Sieber to NRC, June 12, 1987),..
.The staff rtade a proposed no-significant.. hazards determination' en March 12, 4
1966 (51 FR B589).,The licensee's July 25, 1986 and June 12, 1937 submittals
provided only clarificatforvand additional technical support. The staff therefore determined that there was no need to publish a revised NSHC detennination, j
B711200367 871113 PDR ADOCK 05000334 P
t
.PDR n'
- n
q j
1,
1 2.0 DISCUS $10N AND EVALUATION The requested amendment would change the algorithms for the overtemperature -
delta T and the' overpower-delta T trips to take into. account. the cha'n~oeover
]
from.the use of Sostraan RTDs to faster acting RosenountL RTDs.
In addition, a correction would be made to the value of the response time of the overtempera-1 ture-delta.T trip.
?
-The change to the overtemperature-delta T and overpower-delta.T trip algorithms ~.
1 consists of the insertion of lag compensator terms on delta.T and T,Ne.. The lag -
circuits are installed to reduce the probability for spurious trips to the i
fast response of the Rosemount RTDs. The time constants (the lag terms)
- {
appropriately. reflect the plant _ design 'and ensure that correct adjustment of.
-l the lag network will be maintained. Thus-the change has no'effect on the j
safety analysis and is acceptable.
The maximum u mitted value of the response. time for the overtemperature-delta T y
trip has been reduced from 6-to 4 seconds. The 4 second value includes a 2.--
q second allowance for coolant transit and themal' lag response time associated q
with the RTD bypass' manifold. This_ delay is not part of the, instrument response-time and is not measurable.
Furthennore, the change does not. alter.the value used in-the safety analyses, is consistent with what we' stated in our April 22, 1985 letter, and adds conservatism.. We find the change to' be acceptable.
3.0 ENVIRONMENTAL CONSIDERATION
This amendment involves changes installation or use of a facility component located within the restricted area as' defined in 10 CFR Part 20. The staff has determined that the amendment involves no significant increase.in the amounts, i
and no significant change. in the-types, of any effluents that may be released -
{
offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Consnission has previously issued a.
proposed finding that this amendment involves no significant hazards consideration _ and there has been no public comment on such finding. Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth j
in10CFR51.22(c)(9). Pursuant to 10 CFR 51.22(b), no' environmental impact J
statement or environmental assessment need be prepared in connection with the issuance of this amendment.
4.0 CONCLUSION
We have concluded.. based on the considerations discussed above, that: (1)there is reasonable assurance that the health and safety of the public will not be j
endangered by operation in the proposed manner, and-(2) such activities will be conducted in compliance with the Commission's regulations and tt.e issuance of this amendment will not be-inimical to the common defense and security or to the health and safety.of the public.
1 Dated: November 13, 1987 Principal. Contributor:
1 F. Burrows, reviewer
~
W. Brooks, reviewer 1
.-