05000219/LER-1981-024, Forwards LER 81-024/03L-0.Detailed Event Analysis Encl

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Forwards LER 81-024/03L-0.Detailed Event Analysis Encl
ML20030B263
Person / Time
Site: Oyster Creek
Issue date: 07/08/1981
From: Finfrock I
JERSEY CENTRAL POWER & LIGHT CO.
To: Grier B
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20030B264 List:
References
NUDOCS 8108060267
Download: ML20030B263 (4)
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LER-1981-024, Forwards LER 81-024/03L-0.Detailed Event Analysis Encl
Event date:
Report date:
2191981024R00 - NRC Website
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OYSTER CREEK NUCLEAR GENERATING STATION imRgW (609)693-6000 P O BOX 388

  • FORKED RIVER
  • 08731 July 8, 1981 D

fW rj@%

Mr. Boyce H. Grier, Director N

B Office of Inspection and Enforcment S-h Region I g U G 0 5 19a; u --

United States Nuclear Regulatory Ccmnission

- Mg g

631 Park Avenue b

s King of Prussia, Pennsylvania 19406 i'O Th

Dear Mr. Grier:

SUBJECT: Oyster Creek Nuclear Generating Station Docket No. 50-219 Licensee Event Report Reportable Occurrence No. 50-219/81-24/3L This letter forwards three copies of a Licensee Event Report to report Reportable Occurrence No. 50-219/81-24/3L in cmpliance with paragraphs 6.9.2.b.2 and 6.9.2.b.3 of the Technical Specifications.

Very truly yours, an R. Finf Jr.

ice President - JCP&L Director - Oyster Creek IRF:dh Enclosures cc: Director (40 copies)

Office of Inspection and Enf'rcment United States Nuclear Regul a ry Ca mission Washington, D.C.

20555 Director (3)

Offi of Managmient Information

//f and Program Control United States Nuclear Regulatory Cmrtission Washington, D. C. 20555

$s g

NBC Resident Inspector (1)

Oyster Creek Nuclear Generating Station Forked River, N. J.

1 S

OYSTER CREEK NUCLEAR G m ERATING STATION Forked River, New Jersey 08731 Licensee Event Report Reportable Occurrence No. 50-219/81-24/3L Report Date July 8, 1981 Occurrence Date June 8, 1981 Identification of Occurrence The plant was operating in a degraded mode as permitted by a limiting condition for operation as given in Tcchnical Specification paragraph 3.4.C.4, when two Emergency Service Water pumps were found to be inoperable, and the required operability check of the operable pumps was not performed in the time period specified.

This event is considercd to be a reportable occurrence as defined in the Technical Specifications, paragraphs 6.9.2.b.2 and 6.9.2.b.3.

Conditions Prior to Occurrence The plant was operating at steady state power.

Major Plant Parameters Power:

Reactor 1081 b5ft Generator 310 F54e 4

Flow:

Recirculation 12.0xlglb/hr p

3.5 x 10 Feedwater Description of Occurrence At approximately 12:35 A.M. on June 8, an operability check of the Emergency Service Water pumps was performcx1 due to grass clogging probleus at the intake structure. Pump 52B was found to have unacceptable motor current, and pump 52C was found to have unacceptable discharge pressure.

(Based on acceptance criteria given in the Containnent Spray and Emergency Service Water Pump Operability Test procedure, 607.4.001). The rcmaining pumps, 52A in Systan I and 52D in Systan II, met the acceptance criteria.

After discussion with the NBC Resident Inspector, at approximately 11:30 A.M.

on June 9, an operability check was again performed on the four ESW pumps (approximately 35 hours4.050926e-4 days <br />0.00972 hours <br />5.787037e-5 weeks <br />1.33175e-5 months <br /> after the first operability check). Once again pumps 52B (Systan I) and 52C (Systen II) failed to meet acceptance criteria, and 52A and 52D were operable.

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Reportable Occurrence Page 2 Peport No. 50-219/81-24/3L On June 10, the four pumps were again tested, and in addition to measuring notor current and pump discharge pressure, the systan flow was measured using ultrasonic measuring equipnent. Based on the fact that each pump delivered nore than the acceptable flow r: te, the four ESW pumps were then considered operable. The test data for the three (3) days is as follows:

June 8 ESW Pump Disch. Pressure (psig)

Current (amps) i 52A 100 51 52B 100

  • 48 52C
  • 95 51 52D 115 55 June 9 j

ESW Pump Disch. Pressure (psig)

Current (amps) 52A 100 51 52B

  • 95
  • 48 l

52C

  • 97 51 52D 140 54 June 10 ESW Pump Disch. Pressure (psig)

Current (amps) Flow (ggn) 52A 100 50.5 3420 52B

  • 95
  • 47 3830 52C
  • 95 51 3750 52D 115 53.5 4000 Acceptable Limits:

>100 psig pressure 53 + 3 amps current

> 3000 gpn flow (design flow)

  • Denotes unacceptable values Apparent Cause of Occurrence i

Following the June 8 testing of the ESW pumps and after a managenent review of the test data, it was decidal to consider the pumps with questionable i

rmaings operable. This decision was based on past experience of poor correlation between I: ump flow and pressure / current readings. At the same time, engineers were assigned to evaluate the test data and conduct flow tests in order to verify the status of the pumps in question.

Subsequently, it was found that pump flows were well within acceptable limits and in fact the pumps were operable. Additionally, it was found that the amneter on the 'B' pump was faulty ard slight clogging of the pump suctions of 'B' and 'C' pump contributed to the low discharge pressure rmaings.

~

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Reportable u,Ct.irence Page 3 Report No. 50-219/81-24/3L Analysis of Occurrence The Containment Spray and Dnergency Service Water Systes are engineered safety systems designed to rmove fission product decay heat frm the primary containment in the event of a loss of coolant accident. There are two independent syst e s used to accmplish this, with each systs having redundant pumps, each capable of performing the safety function. The systes are designed so that a single Containment Spray pump and a single Dnergency Service Water pump can provide the necessary cooling.

In this case, the safety significance is minimized by the fact that the redundant punp in each systs was operable (52A in Systm I and 52D in Systm II). Based on this, the systs would have been aale to perform - designed function in the event of a IOCA. It should also be noted that the a,of June 10 shows that the punps are still capable of delivering rated flow even with the low current or pressure.

Corrective Action

Since the time of the occurrence, the faulty anneter has been replaced. Emergerg Service Water pumps 52B and 52C were rmoved and the suction bells were cleaned.

Testing perfonned after this maintenance yielded current and pressure readings which were all within acceptable limits.

^

Currently, engineers have been assigned to provide flow instrumentation on this systs in order to provide positive indication of pump operability. In the interim, the pump testing procedure and pump acceptance criteria are being evaluated in order to determine possible changes to provide better irrlication of actual operability status.

In the future when a question on equipnent operability arises as a result of surveillance data or other conditions that can't be inenrhtely dispostioned, a conservative approach will be taken and the subject equignent declared inoperable and the appropriate surveillance performed as required by Technical Specification:

until resolved.

Failure Data l

Manufacturer - Byron Jackson Type -

Vertical-Centrifugal, 3000 gyn,1770 RPM

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