ML19323F391
| ML19323F391 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 05/07/1980 |
| From: | Mills L TENNESSEE VALLEY AUTHORITY |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| IEB-80-07, IEB-80-7, NUDOCS 8005280935 | |
| Download: ML19323F391 (4) | |
Text
/0 TENNESSEE VALLEY AUTHORITY CHATTANOOGA. TENNESSEE 374ot 400 Chestnut Street Tower II May 7, 1980 Mr. James P. O'Reilly, Director
~'
Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Region II - Suite 3100
~
101 Marietta Street Atlanta, Georgia 30303
"[
Dear Mr. O'Reilly:
OFFICE OF INSPECTION AND ENFORCEMENT BULLETIN 80 RII:JPO 50-259, -260, -296 - BROWNS FERRY NUCLEAR PLANT UNITS 1, 2, AND 3 Enclosed is our response to IE Bulletin 80-07 for the Browns Ferry Nuclear Plant, transmitted to us for action by your letter to H. G. Parris dated April 4, 1980. Based on our response to the Niletin action items, and as explained further in the enclosure, continued operation of the Browns Ferry Nuclear Plant is justified and the operating licenses for Browns Ferry units 1, 2, and 3 should not be modified, suspended, or revoked.
Very truly yours, TENNESSEE VALLEY AUTHORITY Q1.Y1 V24 L. M. Mills, Manager Nuclear Regulation and Safety Subscribed d sworn to before me this day of [JI(1/1_
1980.
C uMk
[L[lIJ/LLLL dotaly Public g'
My Commission Expires
[f,
,/
/
Enclosure THIS DOCUMENT CONTAINS l
80.05280 7 3 g POOR QUALITY PAGES An Equal Opportunity Eniployer
ENCLOSURE RESPONSE *TO IE BULLETIN 80-07 BROWNS FERRY NUCLEAR PLANT UNITS 1, 2, AND 3 (DOCKET NOS. 50-239, -260, -296)
Each of the three units of the Browns Ferry Nuclear Plant is presently in an operating cycle. Therefore, our response to IE Bulletin 80-07 addresses the specific items listed under part B of the action to be taken.
Item B.1 The ':KC staff has determined that the operatin; plants warrant inspection as required by paragraph 1 and 2 above.
Therefere, licensees are requested to provide within 30 days of receipt of this bulletin, written justifi-cation for any continued operation until tnese inspections are made and any defects thus identified are corrected.
Response
Underwater camera increction and videotaping of the unit 1 jet pump beam boltkeepers, holddown beams, aad
-a=**=4aa-04 ?es vere performed in February 1980 during the unit 1 refueling outage. No obvious cracking, wear, broken tack welds, or other problems were observed with the jet pumps.
The vendor has indicated that tae problem of jet pump assembly f ailure is related to total operating tima, the patential for failura increasing with time. As of January 1980, the estimated total operating hours of the three Browns Ferry units were as follows: unit 1 - 25,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />; unit 2-22,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />; unit 3 - 19,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />. These operating times are considerably lower than the operating times for the plants which have experienced failure.
We submit tha> the visua.' inspection of unit 1, which has the largest number of opera'.i..g hours, and the action taken to identify and respond to possible jet pump problem. on all units justify the continued operation of Browns Ferry units 1, 2, and 3 until the next refueling outage on each unit.
The present schedule for these outages and estimated total operating hours as of the outage date are as follows:
Unit 2 - September 7, 1980, with 27,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> Unit 3 - October 30, 1980, with 25,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br /> Unit 1 - April 14, 1981, with 35,000 hours0 days <br />0 hours <br />0 weeks <br />0 months <br />
~ ~
During the outages, we will perfor$ Ehe ultrasonic and visual inspections required in items A.1 and A.2.
We will also complete the notification and report requirements in item A.3.
'c.'e pl2= t: repl::: all defective jet pump holddown beams an'd other defective parts found during these inspections.
o 9
5
Item n.2 For plants intending to justify " continued operations or resume operation, the following surveillance, if not already performed, shall be initiated within 10 days after receipt of this bulletin and shall be centinued until the plant technical specifications are revised er the cause of beam failure has been identified and corrected.
This surveillance should improve the ability of the plant to identify an early indication of jet pump degraiation or failure.
Individual jet pump differential pressure readings should be recorded and used to establish a data base for expected charac-teristics for each jet pump.
Periodic surveillance readings and individual jet pump trends when evaluated against this-data base should assist in providing indication of je' pump degradation and
__;;; ment other conditions che:ked ta determine jet pcmp cperabilit.
a.
Fr2;2re the necessary procedure: 2nd perf:rm jet pump :pera-nl.::y surveillance including tne items specif ed in b. below on a daily basis, and following recirculation pump restart, and following unexpected changes observed in core flow indications, recirculation system flow indications, or established power-ccre flew relationships.
b.
If any of the following deviations occur during surveillance, evaluate and record the reasen:
(1) The recirculation pump flow differs by more than 10% frem the cetablished speed-flow characterictics fer that pump.
(2) The indicated total core flow is more than 10*' greater than the core flow value derived fr:m established power-core flow relationships:
(3) The diffuser to lower plenum differential pressure reading on an individual jet pump exceeds the expected charac-teristics established for that pump (B.2 above).
Response
p On April 17, 1980, TVA increased its daily surveillance requirements to meet the intent of this item.
Comparisons of the flows and speeds for the tv,o recirculation pumps is being made. Comparisons of total core flow to expected flow is also being made. Since individual jet pump alfierential pressure varies fut difietent puwet levelo and cerc flows, comparison of individual jet pump differential pressure to the average jet pump differential press'ure is being made to evaluate possible jet pump degradation.
e e
~
. Iten E.3 If it is determined that a jet pump is inoperable or significantly i
degraded, the reactor shall be shutdown in accordance with technical I
specification requirements.
Response
s The action required in this item is our present practice. Appropriate l
,p ant personnel have been made aware of the incidents d'escribed in
' IE Bulletin 80-07 and have been instructed to take appropriate actions as
}
necessary, including reactor shutdown.
1 1
Itam L.4 Review your procedures for instructing plant operaters regarding identification and response to sudden individual jet pump f ailure.
Revise procedures as required and instruct operating staff of any changes.
Response
on April 22, 1980, Emergency Opar :ir.g. ;;ruc:icn ::c. 20 (Jat Pump Failure) was revised in accordance with this item.
In addition, the characteristics of the jet pump failure at Dresden 3 are being verified at the Erewns Ferry simulator, and the ainulator will be modified as necessary to exhibit the correct response.
In this way, the incident is continually incorporated into operator training and retraining. Also, the incident and the revised procedure are being discussed with all licensed personnel
{
in supplemental training onsite.
f s
1 1
)
+
4 e
--