ML20217B751
| ML20217B751 | |
| Person / Time | |
|---|---|
| Site: | Framatome ANP Richland |
| Issue date: | 10/11/1999 |
| From: | Edgar J SIEMENS POWER CORP. (FORMERLY SIEMENS NUCLEAR POWER |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| JBE:99:056, TAC-L31227, NUDOCS 9910130053 | |
| Download: ML20217B751 (3) | |
Text
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.. - SIEMENSL October 11'1999
' JPE:09:056 U. S. Nuclear Regulatory Commission
' Attn: Document Control Desk Washington, D.C. 20555 Gentlemen:
License Amendment Application - SNM - 1227, Docket 70-1257; Addition of the Fuel Services i
Building to the NRC License (TAC NO. L31227)
Ref.: Letter, P.W. Lain to L.J. Maas, " Authorized Activities in the Fuel Services Building -
Request for Additional Information (TAC NO. L31227), dated October 4,1999.
Attached are Siemens Power Corporation's (SPC's) responses to the request for additional information in the referenced letter.
If you require further information, please call me at 509-375-8663.
Very truly yours, Jam s B. Edgar Staff Engineer - Licensing
/las Enclosures 130004'
/ok 9910130053'991011 X
/
PDR ADOCK 07001257-IE C
Siemens Power Corporation 2101 Hom Rapids Road Tel:
(509) 375-8100 RicNand, WA 99352 Fax:
. (509) 'J75-8402
o, 4
ATTACHMENT NRC Ouestions Decommissioning
- 1. Does the proposed new activity in the Fuels Services Building effect the Decommissioning Plan described in Chapter 7 of the license application?
SPC Resoonse The proposed activity should have no effect on the decommissioning plan. The contamination present on fuel ~ assemblies will be the same as that on fuel examination equipment used at reactor sites and returned to the Fuel Services Building. In addition, there will be no contamination from SNM in the building because that material will be contained in the rods.
Criticality Safety -
- 2. ' identify and describe in detail the established criticality safety measures that SPC currently 4
has in use in the UO Building that will be applied in the Fuel Services Building. Specifically 2
identify each controlled parameter, all of the controls used to ensure that double contingency is. met, a description of how these controls ensure that double contingency is met, and any assumptions that were made in the analysis, include any limiting calculations that were performed.
SPC Response
- a. The specific controlled parameters for this process are listed in Table I-4.1 in SPC's material's license SNM-1227, NRC Docket No. 70-1257. The parenthetical section and
' table references behw are from SPC's application for license SNM-1227. The controlled parameters are:
- L Enrichment -less than 5 wt.% 23sU. (section 1.4.1)
Slab height-less than 3.6 inches. (Table 1-4.3, section 14.1.2.6.1, and Table 11-14.1) e Moderation- (14.2.4.5.3 and in various parts of sections 15.1.10.1,15.1.10.2, 15.1.10.3 and 15.1.11)
Spacing-at least 1 foot spacing between transfer carts and other accumulations of fissile material. (14.2.4.6)
- b. The controls used to ensure double contingency is met are described below. They are:
Only'a single fuel assembly can be downloaded at a time.
..There are restrictions on fuel assembly enrichment and on the ratio of volume of water to volume of fuel (V,/V,) for large PWR assemblies.
Rods are placed into an open ended rod tray with the sides of the tray less than 3.6 inches deep.
Siemens Power Corporation
' 2101 Hom Rapids Road -
Tel:
(509) 376-8100 IUcNand, WA 99352-Fax:
(509) 376 8402
~
JBE:99:056 U.S. Nuclear'Hegulatory Commission Attachment o
August 11,1999 Page 2
.The disassembly operation is located in a moderation control area approved by criticality safety.
Transfer carts are equipped with locking bars that ensure a safe geometry even in the event the cart somehow tips over.
' During transport between buildings, a second restraining device (nylon straps) is used to keep rods in the rod tray and the rod tray on the transfer cart,
- c. These controls ensure double contingency is met because:
For the allowed enrichment,' optimally moderated rods cannot go critical when the rods are limited to 3.6" slab. The rod tray and cart designs provide reasonable assurance that the slab height will not be exceeded.
if somehow the allowed slab height is exceeded, criticality is not possible without I
e sufficient moderation. The down!oading area is free from overhead solution lines, plastic is not allowed to be placed between layers of rods on the rod trays. The design of the j
rod trays precludes the accumulation of sufficient amounts of water to optimally moderate the rods if they were somehow optimally pitched, i
- d. _ The analysis uses the following assumptions:
' Limitina Assumotion:
Spacers will not be used between layers of rods.
Conservative assumotion:
Rod trays are assumed to be loaded with optimum diameter fuel rods at an optimum pitch and completely flooded (moderated) with water. Note that rods are limited to a safe slab (3.6 inches) where as a critical slab height of flooded close packed fuel rods is greater than 10.5 inches (conservatively assuming a square pitch). Rods will be close packed if spacers are not used between layers of rods.
e, include any limiting calculations that were performed. The following results came from XSDRN-PM calculations.
Pitch Type Vol.% Interspersed l Slab depth (inches)
K,n, Moderator l
Edge to-edge.3165 inch (0.804 cm) diameter rods-Square 1
na
.88 Triangular na
.90 Square 10 na
.93 Triangu'ar na
.90 Square 100 10.9
.95 Triangular 27.7
.95 Edge to-edge 0.5 inch (1.27 cm) diameter rods Square 100 10.5
.95 Triangular 27.0
.95