ML051750269
| ML051750269 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 06/17/2005 |
| From: | Lochbaum D Union of Concerned Scientists |
| To: | Diaz N NRC/Chairman |
| References | |
| 05-0327, G20050452, LTR-05-0327 | |
| Download: ML051750269 (4) | |
Text
EDO Principal Correspondence Control FROM:
DUE: 07/19/05 David Lochbaum Union of Concerned Scientists EDO CONTROL: G20050452 DOC DT: 06/17/05 FINAL REPLY:
Chairman Diaz FOR SIGNATURE OF :
ROUTING:
Unaddressed Regulatory Implications of "TMI SLIME" Reyes Virgilio Kane Silber Dean Cyr/Burns Collins, RI Paperiello, RES Wallis, ACRS DATE: 06/23/05 ASSIGNED TO:
NRR CONTACT:
Dyer SPECIAL INSTRUCTIONS OR REMARKS:
Add EDO and the Commission for concurrence.
EDO and Commission to review response prior to dispatch.
OFFICE OF THE SECRETARY CORRESPONDENCE CONTROL TICKET Date Printed: Jun 23, 2005 08.52 PAPER NUMBER:
ACTION OFFICE:
LTR-05-0327 EDO LOGGING DATE: 06/2212005 AUTHOR:
AFFILIATION:
ADDRESSEE:
SUBJECT:
ACTION:
DISTRIBUTION:
David Lochbaum UCS Nils Diaz Unaddressed regulatory implications of "TMI SLIME" Direct Reply RF, SECY to Ack
- I LETTER DATE:
06/17/2005 ACKNOWLEDGED SPECIAL HANDLING:
No Made publicly Available in ADAMS via SECY/EDOIDPC NOTES:
Commission should review response prior to dispatch FILE LOCATION:
ADAMS DATE DUE:
07/21/2005 DATE SIGNED:
EDO -- G20050452
w Union of Concerned Scientists Cmdzens and Sdentists fo Environmental Soutons June 17,2005 Dr. Nils J. Diaz, Chairman Mr. Edward McGaffigan, Jr., Commissioner Mr. Jeffrey S. Merrifield, Commissioner Dr. Gregory B. Jaczko, Commissioner Dr. Peter B. Lyons,.Commissioner U.S. Nuclear Regulatory Commission Washington, DC 20555-0001
SUBJECT:
UNADDRESSED REGULATORY IMPLICATIONS OF "TMI SLIME" -
Dear Mr. Chairman and Commissioners:
In 2003, the Advisory Committee on Reactor Safeguards (ACRS) raised a concern about the potential for chemical -effect's't6o dvrs'ely'affb6'e;. th^'hIed loss'acridgsth!aebris bled forming on the containment sump screens at 'presWurizedwater'eactors during the recirculation phases of accidents. The ACRS was reviewing the NRC staffs i'esolution plan for :Gcneric-Safety Issue' 191 (GSI4191)
The'ACRRS becarn'e aware of the memo' dated Septerhbei-t l4,1979, fromrnthe Oak' Ridge Nati6nal Laio'rattiy tb'the 'GPU Service Corporai6n :reporting the 'presence 'of -a gelatinbus 'maeeria' ini 'd'-ate' iariiple' iak'nfr'oni' the Three Mile *IslandUnit 2 containment sump following its'acbidenCt This "lMI gslim'e'7 issue pr6mpted a series of chemical'effects'and head loss testing to aimwerthe ACRS's question':- I; I attended a public meeting on January 8, 2004, between the NRC staff and industry representatives about GSI-191.1 During thAtmeeting, a representative frosnlthetlos'Alanios National Labo'ratory working under contract to the NRC to answer the ACRS's question reported that his inquiry into the' source and nature d'f the TMI slime indicated that approximately -one-third of the water residing in the reactor containment after the accident was untreated water from the Susquehanna River and that the most likely source of this river water was leakage from the containment chillers.
The recent release of reports on the chemical effects and head loss testing address the ACRS's question about the potential impact from gelatinous materials on the resolution plan for GSI-191. There are at least two other regulatory implications of the "Th1I1slime"'that remain to be addressed.:These implications are unrelated to GSI-191,:but viarrant addressifign6nedthleis.iThose two implicationis are:': :;
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- 1) Impact on release pathways: The regulatory requirements governing containment penetrations do not mandatd'autonmatic isolation valves be' installed'for a closed1loop-system such as water-filled 1'
lpiping used to cool components-inside'tlie.lcontaihiientt.The"'underlying assu'mption'ishii a' zi,}-- closed loop X system 'does not represe'n1 a~ipathWayfor radioaictiv'e ni mate'rials 'to 's'caji' froni
- ;containment. :,Appareintly, I one.\\ bf ithe 'l6adifig' candidates' f. ' the' signifi6rnt -'a'nibunt'of
.-,..,-Susquehanna River waterfound in'the-TMI containment is leakage'(romiiaI6sedA-6ojsys'tem.i:
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'4 Washington Office: 1707 H Street NW Suite 600 *Washington DC 20006-3919
- 202-223-6133
- FAX: 202.223-6162 Cambridge Headquarters: TwoBrattleSquare
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June 17, 2005 Page 2 of 2 general, leak(s) in a closed-loop system inside containment cannot pose a potential release pathway for radioactive material as long as the system is operating because pressure of the fluid inside the leaking pipe will likely exceed the containment pressure. When a closed-loop system is not operating, reduced pressure inside its piping could create'the potential for a release pathway.
The questions raised by this implication include: Are operating procedures sufficient to prevent the creation of a release pathway when an operating system with a closed-loop portion inside containment is removed from service?
- 2) Impact on environmental qualifications: Certain equipment, mostly electrical devices, may not function properly when submerged in water. The NRC has issued numerous generic correspondence documents on this subject (e.g., Bulletin 79-OIB, Information Notice 89-63 and Information Notice 2002-12). To demonstrate compliance with the requirements for environmental qualification of equipment inside containment, the submergence level is calculated based on the containment geometry, volume of the make-up water tank, and projected leak rates from systems inside containment. The potential for a significant volume of water to leak into containment, as may have happened in 1979 to produce the -TMI slime and-certainly happened in 1980 to submerge the lower section of the reactor vessel at Indian Point Unit 2, poses a challenge to environmental qualification of equipment.
On behalf of the Union of Concerned Scientists, I respectfully ask that you direct the NRC staff to either verify that both of these implications are fully addressed by existing regulatory requirements or undertake
- steps to address these implications.
Sincerely,
,0faw1 David Lochbaum Nuclear Safety Engineer Union of Concerned Scientists 1707 H Street NW, Suite 600 Washington, DC 20006 (202) 223:6133
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