ML20064M438
| ML20064M438 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 01/28/1983 |
| From: | Ray H SOUTHERN CALIFORNIA EDISON CO. |
| To: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| Shared Package | |
| ML20064M440 | List:
|
| References | |
| NUDOCS 8302150553 | |
| Download: ML20064M438 (4) | |
Text
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S AN ONOFRE NUCLE AR CENER A TING S T A TION P.O. B O X 128 S AN C LEMENTE. C ALIFORNI A 92672 H. B. R A Y v
TELEPHONE January 28, 1983 "ana""aaaa'a
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U. S. Nuclear Regulatory Commission Office of Inspecticn ari Enforcement Region V 1450 Maria Lane, Suite 210 Walnut Creek, California 94596-5363 Attention:
Mr. R. H. Engelken, Regional Administrator
Dear Sir:
Subject:
Docket No. 50-361
(
30-Day Reports Licensee Event Report Nos.83-001 and 83-002 San Onofre Nuclear Generating Station, Unit 2
Reference:
Letters, H.B. Ray (SCE) to R.H. Engelken (NRC),
dated January 5,1983 and November 17, 1982 Pursuant to section 6.9.1.13.b of Appendix A, Technical Specifications to Facility Operating License NPF-10, for San Onofre Unit 2, this submittal provides the required 30-day written report and copies of Licensee Event Reports (LER's) for two similar occurrences involving low water level in the Condensate Storage Tanks, 2T-120 and 2T-121.
Limiting Condition for Operation (LCO) 3.7.1.3 requires that while in Modes 1 - 3, the Condensate Storage Tanks 2T-120 and 2T-121 must be operable with a contained volume of at least 280,00 gallons and 90,000 gallons, respectively (the required content for Tank 2T-121 is based on the maximum power achieved to date of 50%). The associated Action Statement requires that with the tanks declared inoperable, they must be returned to operable status within four hours or the plant must be placed in hot standby (Mode 3) within the next six hours and in hot shutdown (Mode 4) within the following six hours. The Surveillance Requirement 4.7.1.3 requires verification of the contained water volume at least once each 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />.
On January 1,1983 with the plant in Mode 2 at 0.5% power, condensate water from tanks 2T-120 and 2T-121 was being used for various operations.
0302150553 830128 PDR ADOCK 05000361 S
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m R. H. Engelken January 28, 1983 In this particular instance, condensate water from T-121 was being used to feed the Steam Generators, and 2T-120 was t'eing used for condenser make-up due to overboarding the hotwells to control chloride levels due to saltwater leakage in the condenser.
In addition, the Auxiliary Boiler was also in service using condensate inventory from Tank 2T-120.
At 0815 the level in Tank 2T-120 fell below the limits of LCO 3.7.1.3.
Since the level was not restored within the allowable 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, preparations were initiated at 1215 for entry into Mode 3.
The level was restored at 1244 and LC0 3.7.1.3 satisfied. At 1015 the level in Tank 2T-121 fell below the limits of LC0 3.7.1.3.
The level was restored at 1215, thus satisfying LCO 3.7.1.3.
The cause of these incidents was insufficent attention being directed toward maintenance of the minimum volumes required by the Technical Specifications during operations involving high water usage. To compound the difficulty of maintaining the water inventory, there was a shift change of Opera. ors and the turnover instructions did not adequately address the impact of the overboarding operations in progress.
These two events are the most recent in a series of incidents over the past several months wherein the LCO Action Statements were entered. As a result of these past incidents several corrective measures, as reported previously, were developed.
These corrective measures included:
1)
Revision of the Technical Specification requirements for contained volume of tank 2T-121, 2)
Implementation of an automatic tank level control system (now expected to be installed in April,1983), and 3)
Supplementary instruction and training to operating personne..
In addition, although not identified in our various LER submittals, additional operating personnel were assigned to monitor and maintain levels in tanks 2T-120 and 2T-121.
These corrective measures were only partially effective in eliminating periodic entry into the Ar ; ion Statement associated with LC0 3.7.1.3.
Since NRC approval of the Technical Specification change in the required contained volume for tank 2T-121 on October 26, 1982, the Action Statement has only been entered once for low water level in tank 2T-121 (that occurrence being reported by this LER 83-002). Too frequent entering of the Action Statement for low water levels in tank 2T-120 has continued.
Consequently, additional corrective action has been initiated as follows:
R. H. Eng31 ken January 28, 1983 4)
Tank T-120 alarm setpoint was reset on January 24,1983 to be closer to the Technical Specification limit. With the alarm setpoint established at a value which is close to the Technical Specification value, but far enough above that value to provide time for corrective action to be effective, the setpoint will be more meaningful to the Operators.
5)
Two additional tanks of half-million gallon capacity each are expected to be installed and operational by April 15, 1983.
These tanks will provide the normal make-up volume for plant operations during the high usage periods expected during power ascension testing on Units 2 and 3.
6)
A proposed Technical Specification change will be submitted by February 28, 1983 for both Tanks 2T-120 and 2T-121 such that the level requirements will be a function of time after each reactor shutdown. This proposed change will be submitted for the Unit 3 Technical Specifications, also.
Finally, in order to ensure that operator complacency does not contribute to our entering the Action Statement in the future, the following additional corrective measures have been taken:
7)
The Operations Manager has issued verbal orders to the effect that tank 2T-120 cannot be taken below 80% without his permission.
8)
The Operations Manager has met with the Supervisors of each shift to discuss this problem. A written memorandum detailing this discussion will also be distributed to all Operators, including emphasis on the need to abide by all LC0's, and to recognize that LC0 Action Statements are not, by their design, intended to be utilized frequently.
Enclosed LER's83-001 and 83-002 address these events for tanks 2T-120 and 2T-121 respectively. There was no impact on public health or safety as a result of these events.
If you have any questions regarding the above, please contact me.
Sincerely, ik f'41h
Enclosures:
LER's83-001, 83-002
R. H.' Engelken January 28, 1983 cc:
A. E. Chaffee (USNRC Resident Inspector, San Onofre Units 2 & 3)
R. J. Pate (USNRC Resident Inspector, San Onofre Units 2 & 3)
U. S. Nuclear Regulatory Commission Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission Office of Management Information and Program Control Institute of Nuclear Power Operations l
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