ML20009E856
| ML20009E856 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 07/23/1981 |
| From: | Crutchfield D Office of Nuclear Reactor Regulation |
| To: | Counsil W NORTHEAST NUCLEAR ENERGY CO. |
| References | |
| TASK-07-01.A, TASK-7-1.A, TASK-RR LSO5-81-07-077, LSO5-81-7-77, NUDOCS 8107280490 | |
| Download: ML20009E856 (4) | |
Text
..
y% Q -$m o
_y
~ my y'-
.A
?
g' y
i?g m
g,
-y V%
q:
W y
a July 23, 1981 Docket No. 50-245 LS05 07-077 o>
c
< -[ gg *, IISCI A
-11 Mr. W. G. Counsil. Vice President c-Nuclear Engineering and Operations Northeast Nuclear Energy Congany
\\,A"Qaman, P. O. Box 270 Hartford, Connecticut 06I0':
A
/
s
Dear Mr. Counsil:
SUBJECT:
SEP TOPIC VII-1.A. ISOLATION OF REACTOR PROTECTION SYSTEM FROM NON-S&cTY SYSTEMS, INCLUDING QUALIFICATION OF ISOLA-TION DEVICES, SAFETY EVALUATION FOR MILLSTONE 1 The enclosed staff safety evaluation is based on a contractor document that has been made available to you previously. This evaluation supports the findings of the staff safet.y evaluation of Topic VII-1.A and recommends medifi-cations to the Reactor Protection System.
The need to actually implement these changes will be determined during the integrated safety assessment. This topic assessment may be revised in the future if your facility design is changed or if NRC criteria relating to this topic are moditled before the integrated assessment is completed.
Sincerely, Dennis M. Crutchfield, Chief Operating Reactors Branch No. 5 Division of Licensing
Enclosure:
As stated s
cc w/ enclosure:
See next page
$ SI O$8J.Osf SY 8107280490 810723 PDR ADOCK 05000245 j
P PDR g
7
-.tk...SERR;E.N...S.E 0.RM5;DL:PM..[b.k;.IN.....A
- A : D.L.,,,,,',',,,,,,,,,,
~"c'>,5 5 " a"'>
..: d k..RHermano....
WRu sel.l...
.JShea.....
DCrutchfield -.GL nas.
+c
- ^ " > 7N8.1..,,
.712?/81...
7g181.
.7.l[}/81. \\,'
.7/./dB)........ 7/p/81...
s P4RC FORM 318 810 803 P4RCM O240
@FFOCmL RZC@RD__ COW---
'"*h***
d
's ftr. W. G. Counsil cc William H. Cuddy, Esquire Connecticut Energy Agency Day, Berry & Howard ATTN: Assistant Director Counselors at Law Research and Policy One Constitution Plaza Development Hartford, Connecticut 06103 Department of Planning and Energy Policy Natural Resources Defense Council 20 Grand Street 91715th Street, N. W.
Hartford, Connecticut 06106 Washington, D. C.
20005 Northeast Nuclear Energy Company ATTN: Superintendent Millstone Plant P. O. Box 128 Waterford, Connecticut 06385 Mr. James R. Himmelwright Northeast Utilities Service Coapany P. O. Box 270 Hartford, Connecticut 06101 Resident Inspector c/o U. S. NRC P. O. Box Drawer KK Miantic, Connecticut 06357 Waterford Public Library Rope Ferry Road, Route 156 Waterford, Connecticut 06385 First Selectman of the Town l
of Waterford Hall of Records 200 Boston Post Road l
Waterford, Connecticut 06385 John F. Opeka Systens Superintendent Northeast Utilities Service Coapany P. O. Box 270 Hartfcrd, Connecticut 06101 U. S. Environmental Protection Agency Region I Office ATTN: EIS C0ORDINATOR JFK Federal Building Boston, Massachusetts 02203 i
l
SAFETY EVALUATION REPORT MILLSTONE 1
TOPIC: VII-1.A, ISOLATION OF REACTOR PROTECTION SYSTEM FROM NON-SAFETY SYSTEMS, INCLUDING QUALIFICATION OF ISOLATION DEVICES I.
INTRODUCTION Non-safety systems generally receive control signals from the reactor protection system (RPS) sensor current loops.
The non-safety circuits are required ta have isolation devices to insure the independence of the RPS channels.
Requircments for the design and qualificaton of isolation devices are quite specific.
Recent operating experience has shown that some of the earlier isolation devices or arrangements at operating plants may not be effective. The objective of our review was to verify that operating reactors have RPS designs which provide effective and qualified isolation of non-safety systems from safety systems to assure that safety systems will function as required.
II.
REVIEW CRITERIA The review criteria are presented in Section 2 of EG&G Report 0389J,
" Isolation of Reactor Protection System from Non-Safety Systems."
III.
RELATED SAFETY TOPICS AND INTERFACES The scope of review for this topic was limited to avoid duplication of effort since some aspects of the review were performed under related topics.
The related topics and the subject matter are identified below.
Each of the related topic reports contain the acceptance criteria and review guid-ance for its subject matter.
VI-7.C.1 Independence of Onsite Sources VIII-1.A Degraded Grid IX-6 Fire Protection There are no safety topics dependent on the present topic information because proper isolation has been assumed.
IV.
REVIEW GUIDELINES The review guidelines are presented in Section 3 of Report 0389J.
V.
EVALUATION Based on current licensing criteria and review guidelines, the plant reactor protection system complies with all current licensing criteria listed in Section 2.0 of this report except for the following:
1.
IEEE Standard 279, Section 4.7.2, requires isolation devices between RPS and control systems. There are no isolation devices between the nuclear flux monitoring systems and the process recorders and indicating instruments.
. ?.
Isolation devices are not provided to isolate the APRM system from the process computer.
3.
The power supplies for the RPS channels do not qualify as IE equip-ment.
Isolation between each RPS channel aiid its respective power supply is inadequate.
VI.
CONCLUSION The staff's position is that suitably qualified isolators should be provide for the three exceptions noted above or that the acceptability of the present designs be justified by the licensee.
l l
l i
i s