ML20008E380
| ML20008E380 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 09/25/1980 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Gilberts D NORTHERN STATES POWER CO. |
| References | |
| NUDOCS 8010270466 | |
| Download: ML20008E380 (1) | |
Text
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UNITED STATES E
'i NUCLEAR REGULATORY COMMISSION E
REGION lil g"[
0, 799 ROOSEVELT ROAD GLEN ELLYN,ILLINOls 6o137 SEP 2 51980 Docket No. 50-282 Docket No. 50-306 Northern States Power Company ATTN:
Mr. Dennis E. Gilberts Vice President Power Production and System Operation 414 Nicollet Mall Minneapolis, MN 55401 Gentlemen:
This Information Notice is provided as an early notification of a possibly significant matter.
It is expected that recipients will review the informa-tion for possible applicability to their facilities. No specific action or response is requested at this time.
If further NRC evaluations so indicate, an IE Circular or Bulletin will be issued to recommend or request specific licensee actions.
If you have questions regarding this matter, please contac*.
the Director of the appropriate NRC Regional Office.
Sincerely, hb JamesG.Kepp.T
.er Director
Enclosure:
IE Information Notice No. 80-34 cc w/ encl:
Mr. F. P. Tierney, Jr.,
Plant Manager Central Files Director, NRR/DPM Director, NRR/ DOR AEOD Resident Inspector, RIII PDR Local PDR NSIC TIC John W. Ferman, Ph.D.,
Nuclear Engineer, MPCA 8010270 ffg
7 SSINS No.:
6835 i
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40 Accession No.:
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8008220239 IEIN 80-34 UNITED STATES
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NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 September 26, 1980
'IE Information Notice No. 80-34:
BORON DILUTION OF REACTOR COOLANT DURING STEAM GENERATOR DECONTAMINATION Description of Circumstances:
Recently two instances of boron dilution of the reactor coolant system have Both cases were a result of high pressure washing of the steam occurred.
generator tube sheets for decontamination to reduce the radiation levels during eddy current testing and related steam generator work.
Trojan Nuclear Plant miscalculated the excess boric acid On May 29, 1980, required to offset the demineralized water used in washing the tube sheets.
This resulted in the boron concentration of the primary coolant being reduced to less than the minimum required by the Technical Specifications. The dilu-tion was, however, expected since the wash water was allowed to enter the reactor vessel through the nozzles.
On July 5,1980, San Onofre Unit 1 inadvertently diluted the reactor coolant boron concentration.when the high pressure demineralized flushing water leaked by a dislodged nozzle seal. The inflatable seals had been installed to prevent the non-borated water from entering the reactor. The resulting boron concentra-tion was greater than required for shutdown margin, but the p.sitive reactivity added was in excess of that allowed by the Technical Specifications.
This Information Notice is provided to identify potential problem areas involved with decontaminating specific areas of steam generators.
It is expected that recipents will review the potential hazards involved ar.d consider increased monitoring of 1) inflatable seal performance, 2) vessel level, and 3) baron concentration.
Increasing the boron concentration of the primary system prior to performing any decontamination activities or using borated water for washing should also be considered.
It is expected that recipients will review this information for possible applicability to their facilities.
No specific action or response it. requested at this time.
If you have any questions regarding this matter, please contact the Director of the appropriate Regional Office.
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's iS IN 80-34 Siptember 26, 1980 i
RECENTLY ISSUED IE INFORMATION NOTICES Information Date of Notice No.
Subject Issue Issued to 80-33 Determination of Teletherapy 9/15/80 All teletherapy Timer Accuracy (G3) licensees 80-32 Clarification of certain 8/12/80 All NRC and agreement requirements for Exclu-state licensees sive-use shipments of radioactive materials 80-31 Maloperation of Gould-8/27/80 All light water reactor Brown Boveri Type 480 facilities holding OLs volt type K-600S and or cps K-DON 600S circuit breakers 80-30 Potential for unaccept-8/19/80 All boiling water reactor able interaction between facilities briding power the control rod drive scram reactor OLs or cps.
function and non-essential control air at certain GE BWR facilities 80-29 Broken studs on Terry 8/7/80 All light water reactor turbine steam inlet facilities holding flange power reactor OLs or cps
- Supplement to Notification of 7/29/80 All holders of reactor 80-06 significant events at and near-term OL operating power reactor applicants facilities 80-28 Prompt reporting of 6/13/80 All applicants for and required information holders of nuclear power to NRC reactor cps 80-27 Degradation of reactor 6/11/80 All pressurized water coolant pump studs reactor facilities holding power reactor OLs or cps 80-26 Evaluation of contractor -
6/10/80 All Part 50 licensees QA programs
- Operating Licenses or Construction Permits l
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