ML20168A570
| ML20168A570 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 06/16/2020 |
| From: | Christopher Hunter NRC/RES/DRA/PRB |
| To: | |
| Littlejohn J (301) 415-0428 | |
| References | |
| LER 1976-010-00 | |
| Download: ML20168A570 (4) | |
Text
PRECURSOR DESCRIPTION AND DATA NSIC Accession Number:
112309 Date:
March 8, 1976-
Title:
Gas Turbine Becomes Inoperable at Millstone The failure sequence was:
- 1. The isolation condemsor was inoperable.
- 2. It was decided to start the emergency power system (a gas turbine and a diesel generatorlT as a precaution as hurricane Belle passed.
- 3. The gas turbine failed to run because the governor was out of adjustment.
- 4. The reactor was placed in cold shutdown since both the IC and the FWCI systems were inoperable.
Corrective action:
The governor was adjusted.
Design purpose of failed system or component:
- 1. The I.C. is a natural circulation system which serves as a heat sink when the reactor is isolated.
- 2. The FWCI system provides for a source of high pressure coolant given a Loca.
Unavilailiy ofsysem er WSH 400 Unavailability of systoent per WASH 1400:
- Unavailabilities are In units of per demand D-1.
Failure rates are' in units of per hour HR-1.
With The I.C. Inoperable It Was Decided To Initiate The Gas Turbine For Precaution As Hurricane Bell Passed The Gas Turbine Failed To Run Reactor Placed Cold Shutdown In Potential Severe Core Danage No No, violation of Tech Specs No NSIC.112309 -
Actual Occurrence of Gas Turbine Becones Inoperable at Millstone 1
Loss of Reactor Diesel Reactor Made Sub-RCIC/HPCI ADS/LPCI Long Off site Scram Start and critical by the Initiates CS Term Power Load SBLCS Or Rods Are Initiates Core Manually Driven.In Cooling Potential Severe Core Damage Sequence No.
No Yes No Yes Yes No Yes Yes No Yes No Yes Yes Yes Yes 1
2 3
4 5
6 7
8 9
10 11 12 13 14 15 NSIC 112309 -
Sequence~of Interest of Gas Turbine Becomes Inoperable at Millstone 1
CATEGORIZATION OF ACCIDENT SEQUENCE PRECURSORS NSIC ACCESSION NUMBER:
.112309 DATE OF LER:
March 22, 1976 DATE OF EVENT:
March 8, 1976 SYSTEM INVOLVED: I.C., FWCI, Emergency Power COMPONENT INVOLVED:
Governor CAUSE:
Out of adjustment SEQUENCE OF INTEREST: Loss of offsite power.
ACTUAL OCCURRENCE:
Gas Turbine Becomes Inoperable REACTOR NAME:
Millstone 1 DOCKET NUMBER: 245 REACTOR TYPE:
BWR DESIGN ELECTRICAL RATING: 660 Wie REACTOR AGE: 54 yr VENDOR:
General Electric ARCHJITECT-ENGINEERS:
Ebasco OPERATORS:
North East Nuclear Energy Company LOCATION:
Five miles SW of New London DURATION:
12 (a) hours PLANT OPERATING CONDITION:
100% power SAFETY FEATURE TYPE OF FAILURE:
(a) inadequate performance; (b) failed to start;
-D de inoperable; (d) ___________
DISCOVERY METHIOD:
Operational Event.
COMMENT: