ML19330B909
| ML19330B909 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 07/22/1980 |
| From: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | Jackie Jones CAROLINA POWER & LIGHT CO. |
| References | |
| NUDOCS 8008070193 | |
| Download: ML19330B909 (2) | |
Text
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i' UNITED STATES I
8 NUCLEAR REGULATORY COMMISSION n
y
....:9 REGION 11 g
101 MARIETTA ST., N.W., SUITE 3100 ATLANTA, GEORGI A 30303
'88 O
In Reply Refer To:
It 50-325 50-324 Carolina Power and Light Company Atta:
J. A. Jones Senior Executive Vice President and Chief Operating Officer
~411 Fayetteville Street Raleigh, NC 27602 Gentlemen:
Enclosed is Supplement No. 2 to IE Bulletin No. 80-17 which requires action by you with regard to your power reactor facility (ies) with an operating license.
This transmittal confirms the information and action required that was conveyed by telephone to you on July 19, 1980.
In order to assist the NRC in evaluating the value/ impact of each Bulletin on licensees, it would be helpful if you would provide an estimate of the manpower expended in conduct of the review and preparation of the report (s) required by the Bulletin. Please estimate separately the manpower associated with corrective actions necessary following identification of problems through the Bulletin.
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Should you have any questions regarding this Bulletin or the actions required by you, please contact this office.
Sincerely,
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James P. O'Reilly Director
Enclosures:
1.
Supplement No. 2 to IE Bulletin No. 80-17 2.
List of Recently Issued IE Bulletins cc w/ encl:
A. C. To11ison, Jr., Plant Manager v
8oo8070lg3 w.-
i e
SSINS No.:
6820 Accession No.:
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UNITED STATES 8006190032 NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C. 20555 July 22, 1980 IE Bulletin No. 80-17 Supplement No. 2 FAILURES REVEALED BY TESTING SUBSEQUENT TO FAILURE OF CONTROL RODS TO INSERT DURING A SCRAM AT A BWR Description of Circumstances:
At about 3:35 a.m. on July 19, 1980, a manual scram test was initiated at Dresden Unit No. 3.
This test was initiated in accordance with the require-ments of IE Bulletin No. 80-17.
The scram itself was accomplished (i.e.,
control rods inserted). Following the scram, the Scram Discharge Volume (SDV) was monitored by UT in accordance with Item #3 of IE Bulletin No. 80-17.
The UT check followed the normal draining of the SDV at a time when personnel conducting the test believed the SDV to be empty. However, the UT check revealed the scram discharge west header bank to be 80% filled with water (i.e., apparently the drain was not successful).
Upon investigation, it appeared that the SDV vent system did not function due
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to a stuck ball check valve (i.e., a ball check valve functioning as a vacuum breaker). This ball check valve is installed in a tee connection downstream of the vent valve in a one-inch vent header which terminates in the reactor building equipment drain tank (RBEDT). The ball check valve provides a vent path to the reactor building atmosphere in the event the vent header does not.
The vent header itself provides a path to other interconnections and extends into the RBEDT under the surface of water normally contained there.
Additional information has also resulted from scram testing at other BWRs as follows:
1.
At Duane Arnold, the Scram Discharge Instrument Volume (SDIV) drain valve was found installed so that pressure in the SDIV tended to unseat the drain valve disk. This resulted in leakage out of the SDIV during the scram. This was corrected by reversing and reinstalling the valve. The scram tests were performed on July 12 and 13 and the drain valve was corrected before return to power operations on July 17, 1980.
2.
At the Millstone Unit 1, the scram tests were performed successfully on July 11 through 14.
The function of the 10-second delay on scram reset (per Item #2.(j) of IE Bulletin No. 80-17) was tested separately from the scram tests. Review of the separate test results by plant personnel established that the scram reset delay feature was not functioning in the scram circuits due to a wiring error on the circuit boards. This was corrected.
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a IE Bulletin 80, 80-17 Supplement k. 2 July 22, 1980 4
Page 2 of 2 b
v 3.
At Browns Ferry Unit No. 1, a test scram involving two rods was performed on July 19, 1980. The test showed normal response of level switches in the SDIV, When proceeding to drain the SDIV, however, the SDV did not empty n* required and expected. A vacuum in the SDV apparently existed which k*)t the system from draining.
Subsequently, the vacuum was cleared by opefetor actions and the volume drained properly.
Tests are continuing toward determination of the cause and to measure the vacuum.
4.
At h Mil'e Point Unit No. 1, one rod failed to scram during the manual scras ist on July 14, 1980. This was due to a failure of the scram Pi101 valve for that rod.
In view Di thf above-described events, the following actions in addition to those spefified in IE Bulletin No. 80-17, including Supplement No.
1, are to be taken 17 MT licensees.
EachNt: licensee with a SDV vent system that depends on any component 1.
othe:51iha the vent valve alone for proper venting must provide an alter-nauN path continuously open to building atmosphere on the side of the.et*d valve piping away f rom the SDV. This alternate vent path must be ywtfse in its function at all times (i.e., a vent must be effective regv&os of component operability other than the vent valve).
Plaghame made corrections by providing a vent through a standpipe open to Minig atmosphere. This was done at Browns Ferry Unit No. 3 and is
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berthat Dresden ' Units 2 and 3.
It is noted that due consideration
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toi % ical aspects should be included.
An be vent path must"be provided within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> following the telsbee totification on July 19, 1980 in order to continue or commence opesig Reposiswriting within 5 days of the date of this Bulletin Supplement 2.
the gination of your action in' response to the above.
Reports shall be % to the Director of the appropriate NRC Regional Office and a PY%ibe forwarded to the NRC Office of Inspection and Enforcement, C
9 Diviei*W Reactor Operations Inspection, Washington, D.C. 20555.
More infaMue on the details of the Dresdda and Browns Ferry events and modifica% be obtained by contacting the Dresden and/or Browns Ferry operatin % ision. In addition, we understand that a General Electric Company % ce is available for consultation at (408)925-3188.
For all water power reactor facilities with a construction permit, this Bu
. for information only and no written response is required.
Approved Mi80225 (R0072); clearanch expires 7-31-80.
Approval was given undTM5E clearat.:e specifically for identified generic problem's.
IE Bulletin No. 80-17 (Supplement No. 2)
Enclosure July 22, 1980 RECENTLY ISSUED IE BULLETINS Bulletin Subject Date Issued Issued To No.
Supplement 1 Failure of Control Rods 7/18/80 All BWR power reactor to 80-17 to Insert During a Scram facilities holding OLs at a BWR 80-17 Failure of Control Rods 7/3/80 All BWR power reactor to Insert During a Scram facilities holding OLs at a BWR 80-16 Potential Misapplication of 6/27/80 All Power Reactor Rosemount Inc., Models 1151 Facilities with an and 1152 Pressure Transmitters OL or a CP with Either "A" or "D" Output Codes 80-15 Possible Loss Of Hotline 6/18/80 All nuclear facilities With Loss Of Off-Site Power holding OLs 80-14 Degradation of Scram 6/12/80 All BWR's with an e--
Discharge Volume Capability OL j
P i
80-13 Cracking In Core Spray 5/12/80 All BWR's with an
,Spargers OL 80-12 Decay Heat Removal System 5/9/80 Each PWR with an OL Operability 80-11 Masonry Wall Design 5/8/80 All power reactor facilities with an OL, except Trojan 80-10 Contamination of 5/6/80 All power reactor Nonradioactive System and facilities with an Resulting Potential for OL or CP Unmonitored, Uncontrolled Release to Environment 80-09 Hydramotor Actuator 4/17/80 All power reactor Deficiencies operating facilities and holders of power reactor construction permits 80-08 Examination of Containment 4/7/80 All power reactors with Liner Penetration Welds a CP and/or OL no later than April 7, 1980
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