ML19257D674
| ML19257D674 | |
| Person / Time | |
|---|---|
| Site: | Zion File:ZionSolutions icon.png |
| Issue date: | 01/15/1980 |
| From: | Lantz E Office of Nuclear Reactor Regulation |
| To: | Atomic Safety and Licensing Board Panel |
| Shared Package | |
| ML19257D675 | List: |
| References | |
| NUDOCS 8002050386 | |
| Download: ML19257D674 (3) | |
Text
.
UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION BEFORE THE ATOMIC SAFETY AND LICENSING BOARD In the Matter of
) Docket Nos. 50-295
)
50-304 COMMONWEALTH EDISON COMPANY
)
(Proposed Amendment to Facility Operating
)
License No. DPR-39 and DPR-48 to Permit (Zion Station, Units 1 and 2)
)
Storage Pool Modification)
SUPPLEMENTAL AFFIDAVIT OF EDWARD LANTZ I, Edward L antz, being duly sworn, do state as follows:
I am employed by the U.S. Nuclear Regulatory Commission as an Engineering Systens Analyst, Plant Systems Branch.
I am responsible for technical reviews and evaluations of component and system designs ano operating characteristics of licensed nuclear power reactors. The statement of my prcfessional qualifications has been pre-viously filed in this matter.
This affidavit is in response to the Atomic Safety and Licensing Board question as to whether or not the water in the Zion spent fuel pool would be a " stagnant, oxygenated, borated water system," as defined by the NRC Staff on page 3 of I.E.
Bulletin No. 79-17, Revision 1, dated 29 October 1979; and whether the water inside the proposed vented fuel storage tubes would be a " stagnant oxygenated borated water system."
This definition of a " stagnant, oxygenated, borated water system" is stated in the referenced bulletin as follows:
For this review, the term " stagnant, oxygenated borated water systems" refers to those systems serving as engineered 1872 344 3oceo3o38%
safeguards having no normal operating functions and contain essentially air saturated borated water where dynamic flow conditions do not exist on a continuous basis.
The spent fuel pool and the proposed vented fuel storage tubes in the racks in the pool can be considered engineered safeguards, but they do have a normal operating function.
In this respect they do not comply with this definition.
The water in the Zion spent fuel pool is essentially oxygen-saturated borated water, but it is circulated by cooling pumps and by natural convection. The cooling pumps take the hot water off of the top of the pool at one end and force it through a heat exchanger, where it is cooled, and then force it to the bottom of the other end of the pool. f!atural convection circulation takes place due to having different temperature, and hence different density, water at the.same elevation in adjacent regions in the pool.
The forced convection flow in the pool will have two components, an upward component and a horizontal component. The average, upward velocity in the Zion spent fuel pool without any racks or spent fuel in it due to one pump pumping 2300 gpm through it would be on the order of ten feet per hour. The average horizontal velocity would be a little larger due to the smaller flow area, but it would be the same order of magnitude.
If the flow rate is maintained at 2300 gpm, these velocities will be larger with racks and spent fuel in the pool. The more solid the material placed into the pool, i.e., the higher the fuel storage density, the larger these velocities will be for the same flow rate because of the decreased flow area.
1872 345 In natural circulation flow a vertical loop is established in which the water flows upward through the heat source region and downward through a cooler adjacent region. The upward velocity along a heat source is a direct function of the amount of heat in it. Thus,in a heat source region, i.e., a storage location with a spent fuel assembly in it, the natural circulation flow will enhance the upward, forced convection flow. Therefore, the water will not be stagnant in any storage location which has a spent fuel assembly in it. The natural circulation flow in a cooler region is downward, and it therefore tends to oppose the upward forced convection flow in that region. Thus in these regions it may at times be possible for these two velocities to cancel. The result could be regions of relatively stagnant water in some local areas in the pool.
The above discussion does not relate to the water present at the interface be+. ween the Boral and its S5304 cladding. That water would be within the referenced definitions of " stagnant, oxycenated borated water."
The above statements are true and accurate to the best of my knowledge.
,= l Edward Fantz Subscribed and sworn to before me this 15th day of January, 1980.
g.,
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~~
Notary Public My Coruission expires: July 1, 1982 1872 346
.