ML19209C550
| ML19209C550 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 08/10/1979 |
| From: | Lantz E Office of Nuclear Reactor Regulation |
| To: | Lainas G Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML19209C546 | List: |
| References | |
| NUDOCS 7910160126 | |
| Download: ML19209C550 (2) | |
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DISTRIBUTIOM m-l Central File's Ig
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E MOR.A.MDUM FOR:
G. Lainas, Chief, Plant Systems Branch, 00R I
1 E. Adensam, Section Leader, Plant Systers Branch, 00R
-THRU :
i FROP.:
E. Lantz, Plant Systems Branch, DOR
SUBJECT:
YELEPHONE INTERVIEW WITH XAREN AYERSON OF THE REW YORK TIMES ON THE USE OF BORON TO PREVENT CRITICALITY IN SPENT FUEL POOLS l
In a telephone interview on August 7,1979, Karen Averson wanted to know the history of the use of bon >n to preclude criticality in spent fuel pools. She was familiar with the various types of boron now being used, i.e., Boral, boron carbide in graphite, boron carbide in composite polyner, and Boroflex, but wanted to know if all of these bad been approved by the MRC for use in spent fuel pools and wanted to know about l
the problems with each. My answer was as follows:
Boral has been used in the Yankee Rowe spent fuel pool since 1961.
1.
Other plants, especially in New Englano, started using it in the mi d-1970's. Thus, the use of Boral in spent fuel pools has been approved by the NRC for ecme time.
2.
The experience with Boral as a permanent neutron absorber in spent fuel pools has been very good. We have found that the boren carbide in it does not degrade and that, while the aluminum in it tends to become more brittle, it does not degrade in any significant way.
3.
The next absorber material to be approved by the NRC for spent fuel pools was bomn carbide in graphite plates. The NRC approved 7
h this for Haddam Neck in Movember 1976 and for several other plants There was a swelling problem at the Haddam Neck plant after that.
bMause the manufacturer had not baked out the phenolic binder, as the licensee implied it would do in its submittal to the NRC, The
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but this did not effect the r.eutron absorption capaF swelling was eliminated by venting.the cans into whic..
- a plates All of the racks with these graphite,.ates have had been sealed.
1arge amounts of boron in them and consequently are conservatively
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designed. Also, we do not expect a significant loss of bomn from these plates over the 40 year life of the plants.
4T 255 7 91016 0 / c7 b l
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The other two plater $terials,1,s.'.' the composite polymer and the 4.
Seraflex, will have phenolics in them throughout their existence in the spent fuel racks. These phenolics are made up of hydrogen, The high energy i
oxygen, and carbon as well as some other materials.
ga r.a radiation in the spent fuel pool will tend to decompose these i
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Thus, the licensees phenolics and rele<se the hydrogen atoes.have to show by irradia
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j the highest radiation dose that could possibly be obtained during the for*4 year life of the spent fuel pool without significantly l
degrading and losing more boron than was accounted for in the 4
At the present time the Point Beach criticality calculations.
racks with Boraflex in ther. are the on'fy ones of these to get i
final MRC approval, but MRC approval of the Lacrosse and Crystal i
River Unit 3 racks is exW t
I l
E. Lantz i
Plant Systems Branch Division of Operating Reactors l
cc:
F. Ingram t
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PSB: DOR SL-PSB: DOR Etantz:dn EAdensam 8/ /79 8/ /79
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