ML20198F571
| ML20198F571 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 10/21/1985 |
| From: | Watson R CAROLINA POWER & LIGHT CO. |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| CON-NRC-396, REF-PT21-85, REF-PT21-85-466-000 183, HO-850467-(O), PT21-85-466, PT21-85-466-000, NUDOCS 8511140384 | |
| Download: ML20198F571 (4) | |
Text
a
~
CP&L Carolina Power & Light Company SHEARON HARRIS NUCLEAR PROJECT P. O. Box 101 h,Li b g)
New Hill, N.C. 27562 007 2 1 565 File Number:
SHF/10-13510E NRC-396 Letter Number: HO-850467 (0)
Dr. J. Nelson Crace co United States Nuclear Regulatory Commission tn Region II CD 101 Marietta Street, Northwest (Suite 2900)
E3 Atlanta, CA 30323 gg CAROLINA POWER & LICHT COMPANY
- )
SHEARON HARRIS NUCLEAR POWER PLANT CD
~~
1986 - 900,000 KW - Unit 1 POTENTIAL OVERPRESSUR1ZATION OF THE C#'
C' COMPONENT COOLING WATER SYSTEM, ITEM 183
Dear Dr. Crace:
Attached is our final report on the subject item, which was deemed reportable per the provisions of 10CFR50.55(e) and 10 CFR, Part 21 on August 13, 1984. With this report, Carolina Power & Light Company considers this matter closed.
If you have any questions concerning this matter, please do not hesitate to contact me.
Yours very truly, 20 &
R. A. Watson Vice President Shearon Harris Nuclear Power Plant RAW /cwj Attachment l
l cc: Messrs. C. Maxwell (NRC-SHNPP) l J. M. Taylor (NRC) 851114
'i 851021 PDR
^
s 050004o0 s1 PDR TED?
CAROLINA POWER AND LIGHT COMPANY SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1 FINAL REPORT POTENTIAL OVERPRESSURIZATION OF THE COMPONENT COOLING WATER SYSTEM ITEM #183 SEPTEMBER 20, 1985 REPORTABLE UNDER 10CFR50.55(e) and 10CFR21
SUBJECT:
10CFR50.55(e) and 10CFR21 Reportable Item Shearon Harris Nuclear Power Plant Potential Overpressurization of the Component Cooling Water System.
ITEM:
Component Cooling Water System for SRNPP Unit One.
SUPPLIED BY:
Westinghouse Reactor Division.
NATURE OF DEFICLENCY:
Westinghouse notified the NRC under 10CFR21 on July 12, 1984, of a reportable item issociated with the design of the Westinghouse-supplied component cooling i
water system. An overpressure condition could result from closure of the surge tank vent valve on a high radiation signal from the radiation detectors within the component cooling water aystem. Closure of the vent valve could result in an increase in pressure in the surge tank due to a system inleakage or an increases in system heat load.
The pressure in the 4
surge tank could then increase to the set pressure of the surge tank relief valve. System overpressurization of up to 170% of the design pressure may then occur downstream of the CCW pumps as a result of pump developed head.
DATE PROBLEM WAS CONFIRMED TO EXIST:
Westinghouse letter CQL-8065 dated July 23, 1984, and l
received July 27, 1984.
I DATE PROBLEM REPORTED:
N. J. Chiangi notified the NRC (Mr. A. Hardin) that this item was reportable under 10CFR50.55(e) and l
10CFR21 on Auguc~ 33, 1984.
SCOPE OF PROBLEM:
Unit ! Component Cooling Water System (both trains)
SAFETY IMPLICATIONS: Overpressurizction and potential loss of both component cooling water trains.
4 1
i
. +
REASON PROBLEM l
IS REPORTABLE: Overpressurization could lead to a degraded safety condition and loss of an ESF system.
CORRECTIVE ACTION:
As automatic isolation of the surge tank vent line is
}
not an essential function, Westinghouse has revised the system design by deleting the surge tank vent valve and changed the circuitry such that the high radiation alarm is maintained on the main control board. Also within that design change Westinghouse
].
deleted the relief valve thus creating an open line to an available floor drain. This methodology i
utilizes " leak before break" technology to alleviate j
postulating large inflows of water resulting from a double-ended tube rupture. Mass addition was also lessened by the insertion of,two orifices in the supply lines for the CCW system which limits inflow to fifty GPM. These design changes have been approved by both CP&L and Westinghouse and have been 4
formally issued to our construction organization.
FINAL REPORT: Carolina Power and Light considers the changes outlined to be an acceptable means of resolving the reportable deficiency. The Component Cooling Water System has been redesigned and this item is considered complete.
1 l
t 4
l
..