ML19259B428
| ML19259B428 | |
| Person / Time | |
|---|---|
| Site: | La Crosse File:Dairyland Power Cooperative icon.png |
| Issue date: | 01/31/1979 |
| From: | Linder F DAIRYLAND POWER COOPERATIVE |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| TASK-09-01, TASK-9-1, TASK-RR LAC-6098, NUDOCS 7902090312 | |
| Download: ML19259B428 (5) | |
Text
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ILSIItYLitNIb POWEIt C00PEftstTAVE fa Crosse, Ohconsin 54601 January 31, 1979 In reply, please refer to LAC-6098 DOCKET NO. 50-409 Director of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D.
C.
20555
SUBJECT:
DAIRYLAND POWER COOPERATIVE LA CROSSE BOILING WATER REACTOR (LACBWR)
PROVISIONAL OPERATING LICENSE NO. DPR-45 PROPOSED MODIFICATION - SPENT FUEL STORAGE
Reference:
(1)
NRC Letter, Ziemann to Linder, dated December 29, 1978.
Gentlemen:
Enclosed with this letter is additional information required for your review of the proposed modification of the LACBWR spent fuel storage pool.
This information is provided in response to those items listed in the enclosure of the above referenced letter.
Please contact us if additional information is required.
Very truly yours, DAIRYLAND POWER COOPERATIVE hvIl p
Frank Linder, General Manager FL:NLH:af Enclosure cc:
(See attached list).
7902090 3/2
i Director of Nuclear Reactor Regulation LAC-6098 Washington, D. C.
20555 January 31, 1979 cc:
J. G. Keppler, Regional Director U. S. Nuclear Regulatory Commission Directorate of Regulatory Operations Region III 799 Roosevelt Road Glen Ellyn, IL 60137 Charles Bechhoefer, Esq., Chairman Atomic Safety and Licensing Board Panel U. S. Nuclear Regulatory Commission Washington, D. C.
20555 Mr. Ralph S. Decker Route 4 Box 190D Cambridge, MD 21613 Dr. George C. Anderson Department of Oceanography University of Washington Seattle, Washington 98195 O. S. Hiestand, Jr.
Attorney at Law Morgan, Lewis & Bockius 1800 M Street, N. W.
Washington, D. C.
20036 Kevin P. Galle,n Attorney at Law Morgan, Lewis & Bockius 1800 M Street, N. W.
Washington, D. C.
20036 Coulee Region Energy Coalition P. O. Box 1583 La Crosse, WI 54601 Response to NRC Requests for Additional Information Submitted by NRC Letter, Ziemann to Linder, Dated December 29, 1978 Proposed Modification - LACBWR Spent Fuel Storage Item 1 Provide the distribution of eines of boron carbide (B C) 4 that vill be in the B C/ Polymer Composite plates particles 4
and describe hou the self chielding of the B C particica 4
was accounted for in detcrmining the effective absorption croca section of the plates.
DPC RESPONSE:
The B C particle size distribution used in the Carborundum 4
Composite poison material is as follows:
B C Particle Size Distribution in Carborundum Poison Material 4
Selve Number Corresponding Nominal Fraction of Particles Sieve Opening (inches)
Retained by Seive, %
+35
.020 2.0
+60
.010 10.0
+120
.005 50.0 The nuclear analysis for the LACBWR high density fuel storage racks (NES Document 81A0547) was performed using diffusion theory, with blackness theory used to represent the B4C poison material.
The blackness theory was used to provide diffusion coefficients and absorption cross sections for regions which were too poisonous for diffusion theory to treat.
In the blackness theory treatment for LACBWR, the 0.100 inch thick poison slab was treated as the black region, without any smearing of nearby water gaps.
The B C poison was taken to be homogen-4 cously distributed throughout the 0.100 inch region.
Since the blackness theory cannot treat particle size effects, an auxiliary calculation was performed with KENO, a Monte Carlo code, to determine if there is any effect due to particle sizes in the range from 0.000" to 0.010", the sizes used in the manufacture of the poison.
In this auxiliary calculation, a generalized model which included alternating sections of fuel, water, and poison plates was set up and the effect of changing the particle size from zero (the homogeneous case) to as much as 0.020 inches was investigated.
The increase in Keff for particle sizes up to 0.010" is less than the uncertainty in the K gg value computed e
by KENO (approximately 1%).
Since 90% of the particles are smaller than 0.010", it is concluded that the effect of particle size on Keff is negligible.
The increase in Keff for particle sizes of 0.020" is only 0.9%
Ak/k, so that even if all of the B C particles were of this 4
size, the K gg for the LACBWR racks would still satisfy the e
criticality criterion.
Item 2 Identify uhat system (a) vould be availabic to provide make-up vater to ~ the Fuel Element Storage Welt (FESW) in the event the spent fuel cooling eyetem becomes inoperable.
Indicate the calculated boit-off rate of the poot vater and compare it to the make-up rate available from each source.
Also indicate uhat operator action vould be required to utilize each source and hou tong it could take to initiate thoec actions.
DPC RESPONSE:
Make-up water to the FESW is available from the following sources:
Approximate Estimated Time Operator Make-Up to Initiate Source Action Rate Make-Up Overhead Storage Open Manual Valves 7,000 GPM
< 15 Minutes Tank (OHST) in Supply Pipe to Cooling System rnmineralized Open Manual Valve 15 GPM 5 Minutes Water Hose by Hose Station Station Located Near FESWd A small section of the fuel pool cooling system piping must be used if make-up water is added from the OHST to the FESW.
This piping is isolable from the rest of the cooling system.
Since water flow from the OHST to the FESW is by gravity,
'he cooling c
system pumps are not required to add water to the FESW.
The calculated evaporation rate of the pool water at saturation temperature without the cooling system in service is approximately two (2) gallons / minute, based on a maximum heat load of 9.31 x 105 BTU /hr from a 1/3 core (24 assembly) discharge in 1990, one (1) year after the previous 1/3 core discharge.
- Demineralized water transfer pump powered from redundant essential busses.
(Ref. Evaluation of Fuel Pool Cooling Requirements with Expanded Fuel Storage Capacity submitted by DPC Letter LAC-5341, Madgett to Director of Nuclear Reactor Regulation, dated June 7, 1978).
This evaporation rate is well below the make-up rate available from either the OHST or demineralized water hose station.
Although not a normal make-up water source for the FESW, water could also be added to the FESW from a nearby fire hose station.
The fire hose station is connected to the high pressure service water system which uses two diesel engine driven pumps taking suction from the Mississippi River.