ML19330A753
| ML19330A753 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 05/28/1980 |
| From: | Dotzler T NUCLEAR REGULATORY COMMISSION (TNRC), SUMMERTOWN |
| To: | NRC COMMISSION (OCM) |
| Shared Package | |
| ML19330A747 | List: |
| References | |
| NUDOCS 8007290296 | |
| Download: ML19330A753 (3) | |
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BEFORE THE COMMISSION M>
d Type B Petition by V
THE NUCLEAR REGULATORY COMMISSION Petitioner, the Nuclear Regulatory Commission (TNRC),
a five-member musical group located at 156 Drakes Lane, Summertown, TN 38483, requests under 10 CFR ES 2.206, 2.202, 50.35, and 55.40 that the United States Nuclear Regulatory.
Commission (USNRC) revoke the limited Operating License of the Tennessee Valley Authority (TVA) to perform low power testing of the Sequoyah Nuclear Plant (SQNP) because public health and safety is endangered by even limited operation of this facility.
Prior to the March 28, 1979 accident at the Three Mile Island Nuclear P15 tnt (TMI), SONP Unit 1 was constructed to withstand a pressure on the containment vessel of only 12 pounds per square inch (psi), based upon Westinghouse and TVA belief that the ice-condenser pressure-suppression system.
would be adequate to keep temperatures of small amounts of hydrogen, as well as steam, below potentially explosive levels.
Neither TVA nor USNRC anticipated a hydrogen explosion of the magnitude experienced at TMI when SONP was constructed.
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At 9 hours1.041667e-4 days <br />0.0025 hours <br />1.488095e-5 weeks <br />3.4245e-6 months <br />, 50 minutes into the accident at TMI, there was a sudden pressure spike of 28 to 120 psi to the containment building of TMI Unit 2 caused by hydrogen combustion. The estimated quantities of hydrogen produced during the TMI accident imply oxidation of 45 to 50 percent of the available zirconium cladding. This degree of oxidation is consistent with an estimated 40 to 50 percent of core damage obtained by measurements of cesium and iodine in TMI primary coolant.
Prior to TMI, liberation of hydrogen in these quantities, 400-450 kilograms, was thought to be very unlikely by USNRC.
A hydrogen combustion pressure spike of the magnitude experienced at TMI would exceed SONP conta!.nment pressure rating as built and could result in a loss of containment vessel integrity, an essential barrier to the environment.
Under some circumstances, actual structural material strengths will withstand pressure loads which exceed design specifications. These circumstances depend upon the particular j
and unique stress pattern created by the single-occurreics 1
event causing pressure to exceed design limits, which is not predictable. Safety dictates therefore that design specifications 1
should not be regarded as "exceedable."
l In light c f operating experience obtained at TMI, a multiple-failure accident sequence, significant core damage, hydrogen liberation and combustion, and major metal-water reactions must be regarded as plausible occurrenae in
- large, pressurized-water reactors. The containment building at Sequoyah Unit 1 could provide inadequate protection in the -..
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event of a TMI-type accident. A multiple-failure accident sequence and fuel damage could occur within SQNP at even the low power levels currently generated. SQNP Unit 1 as built would provide even less protection from an accident of this type than did TMI Unit 2.
10 CFR 5 50.35 provides that a license to operate will not be issued until the final design provides reasonable assurance that the health and safety of the public will not be endangered by operation of the facility. 10 CFR 9 55.40 (b) provides that any license may be revoked because conditions revealed by any means would have warranted the Commission to refuse to grant a license on the original application.
Therefore the petitioner requests that the limited Operating License of Sequoyah Unit 1 be revoked in order to protect the public health and safety, and for such other action as may be proper. This revocation should be made effective immediately.
Dated this 28th day of May, 1980.
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g id$ N Thomas botzler
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Chairman The Nuclear Regulatory Commission The Farm Summertown, Tennessee 38483 (614) 964-3574