ML19321A152
| ML19321A152 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 07/17/1980 |
| From: | Mills L TENNESSEE VALLEY AUTHORITY |
| To: | Schwencer A Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8007220532 | |
| Download: ML19321A152 (5) | |
Text
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~~ENN ESSEE VALLZY AUT'"CRITY c e mcc n. Trm.:nI: r :::
400 Chestnut Street Tower II July 17, 1980 Director of Nuclear Reactor Regulation Attention:
Mr. A. Schwencer, Chief Light Water Reactors Branch No. 2 Division of Licensing U.S. Nuclear Regulatory Commission Washington, DC 20555
Dear Mr. Schwencer:
In the Matter of
)
Docket No. 50-327 Tennessee Valley Authority
)
TVA proposes to install and implement an interim system of distributed ignitors which would limit the effects of large amounts of hydrogen such as that generated during the Three Mile Island accident.
On or before August 15, 1980, TVA will submit to the NRC for your review and concurrence the safety analysis, detailed drawings, Final Safety Analysis Report revisions, test requirements document, and proposed revisions to the emergency operating instructions.
TVA has determined pursuant to 10 CFR 50.59 that installation is not an unreviewed safety question. However, implementation of this system has been determined to be an unreviewed safety question. Therefore, the operation of this system will not be initiated until TVA has NRC approval.
Enclosed is the TVA presentation material requested by L. S. Rubenstein which defines the interim distributed ignition system.
Very truly yours, TENNESSEE VALLEY AUTHORITY L. M. Mills, Manager Nuclear Regulation and Safety Enclosure Qbf'g,\\
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Degraded Core Task Force Program 3
Major Tasks 1.
Controlled Ignition 4
2.
Halon e
3.
Risk Assessment
-4.
Core Behavior, Hydrogen Generation and Transport
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5.
Hydrogen Burning and Containment Responses 6.
Containment Integrity 7.
Equipment Environmental Qualifications i
8.
Radiation Dose Code 9.
Hydride Converter, Fogging, and Others 10.
Rulemaking and State of the Art i
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s Distributed Controlled Hydrogen Ignition System Phase 1 (Interim)
Off-the-shelf system components.
Ignitors Thermal resistor (glow plug) 1500*F surface temperature A
1 Possibly supplied by Fostoria Industries Powered by backup lighting circuits (seismic, diesel)
Remote manual control from auxiliary building To be implemented with the next two months 3
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Distributed Controlled Hydrogen Ignition System Phase 2 (Improved)
Each ignitor to have individual control from main control roow.
More hydrogen and oxygen monitors to guide operator Plant computer to warn of detonation limit Backup diesel power supply Small and large LOCA environment (pressure, temperature, humidity, radiation)
Hydrogen burn environment Ignitor locations to be chosen Hydride converter near RV vent, PORV discharge, and air return fans to be considered Additional containment penetrations To be implemented in parallel with "long term" (2-year) program Distributed Controlled Hydrogen Ignition System Phase 3 (Final)
Modifications to phase 2 system will be implemented upon completion and based on results of "long-term" study b
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PHASE 1 SCHEDULE 1
Completion Date i
1.
Provide-Safety Analysis, Detailed Drawings, FSAR Changes, Test Requirements, and vperating Instructions (Procedures) to NRC 8/15/80 I
2.
Installation and Testing Completed on or before 9/15/80 3.
System operational Upon NRC approval i
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