ML19305A768
| ML19305A768 | |
| Person / Time | |
|---|---|
| Issue date: | 11/30/1979 |
| From: | NRC OFFICE OF STANDARDS DEVELOPMENT |
| To: | |
| Shared Package | |
| ML19305A769 | List: |
| References | |
| TASK-FP-925-5 REGGD-03.XXX, REGGD-3.XXX, NUDOCS 8002270500 | |
| Download: ML19305A768 (3) | |
Text
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~ A U.S. NUCLEAR REGULATORY COMMISSION January 1980 j
OFFICE OF STANDARDS DEVELOPMENT Division 3 ORAFT REGULATORY GUIDE AND VALUE/ IMPACT STATEMENT Task FP 925-5
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Contact:
M. S. Weinstein (301) 443-5910 NUCLEAR CRITICALITY SAFETY FOR PIPE INTERSECTIONS CONTAINING AQUEOUS SOLUTIONS OF ENRICHED URANYL NITRATE f
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A.
INTRODUCTION A
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Section 70.22, " Contents of Applications," of 10 CFR Part 70, " Domestic v
w Licensing of Special Nuclear Material," requires that a'ppJications for a specific license to own, acquire, deliver, receive,Jposse'ss[use, or transfer specialnuclearmaterialcontainproposedproceduresttiyavoidaccidentalcon-ditions of criticality.
Thisregulatoryguidepr$fi'ddsguidanceforcomplying with this portion of the Commission's regulations b'y+ describing procedures acceptable to the NRC staff for the prevent, ion of! criticality accidents in the storage and processing of aqueous solutions,s " enriched uranyl nitrate in pipe s
.. of intersections.
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BJJDISCUSSION 1
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u a ANSI /ANS-8.9-1978, " Nuclear CritTcality Safety Guide for Pipe Intersections Containing Aqueous Solutions of Enriched Uranyl '!trate,"1 was prepared by Sub-committee 8, FissionableaMaterials Outside Reactors, of the Standards Committee s
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of the American NucleariSoci'etf. ANSI /ANS-8.9-1978 was approved by the American National Standards Commitheir N16, Nuclear Criticality Safety, in 1977 and sub-3 m
sequentlybytheAgica7NationalStandardsInstitute(ANSI)onFebruary 15, 1978.
ANSI /ANS-8.5-4s applicable only to the storage and processing of homogeneous aqu solutions of uranyl nitrate containing no more than 93.5 wt-%U-235inintefsectingpipegeometriesconsistingofsinglecentralcolumns 2 Copies may be obtained from the American Nuclear Society, 555 North Kensington Avenue, La Grange Park, Illinois 60525.
This regulatory guide and the associated value/ impact statement are being issued in draft form to involve the pubile in the early stages of the development of a regulatory position in this area. They have not received complete staff review and do not represent an official NRC staff position.
Public comments are being solicited on both drafts, the guide (Including any feptementation schedule) and the value/ impact statement. Comuments on the value/ impact statement should be accompanied by sucoorting data.
Ceauments on both draf ts should be sent to the Secretary of the Cosumission. U.S. Nuclear Regulatory Casumission, Washington, D.C. 20555, Attention: Docketing and service Branch, by MiiR 1 4 13@C Requests for single copies of draf t guides (which may be reproduced) or for placement on an automatic distribution list for single copies of future draft guides in specific divisions should be made in writing to the U.S. Nuclear Regulatory Commission, Washington. 0.C. 20555, Attention: Director.
Division of Technical Information and Document Control.
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9 with smaller intersecting arms.
The standard presents tabulated maximum safe values, derived from an empirical model based on validated calculations and
-experimental data', for both the central column diameter and the total area of intersection of the arms with the column for conditions of partial and total
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reflection. - The standard f also presents a general procedure to ascertain the
. safety of. specific pipe intersections as well as guidance on model parameters
'and lim'itations..'In intersecting pipe geometries where the model does not apply,: e.g., multiple -columns or columns in the vicinity of other fissionable materials,-the standard requires that experimental data or validated computa-tional techniques be used to determine the' safe configuration.
C.
REGULATORY POSITION The nuclear criticality safety practices and guidance'for calculating safe pipe intersections for enriched uranyl nitrate solutions contained in ANSI /ANS-8.9-1978 provide procedures generally acceptable to the NRC staff for the prevention of criticality. accidents in the storage and processing of aqueous solutions of enriched uranyl nitrate in pipe intersections subject to the following:
1.
Use of ANSI /ANS-8.9-1978 is not a substitute for detailed nuclear criticality safety analyses for specific pipe intersections.
2.
Section'6 of ANSI /ANS-8.9-1978 lists additional documents referred to in the standard.
The specific applicability or acceptability of these listed documents will be covered-separately in other regulatory guides, where appropriate.
O.
IMPLEMENTATION The purpose of this section is to provide information to applicants regard-ing.the NRC. staff's plan for using this regulatory guide.
The proposed guide has been released.to encourage'public participation in its development.- Except in those cases in which an applicant proposes an 1 acceptable alternative method for complying with specified portions of the Commission's regulations, the method to be described in the active guide reflecting public comments will be used in'the evaluation of submittals for t
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specialinuclear material' Ifcense applications:: docketed after the implementation --
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I'mplementation by the staff will.in.
.date to'be specified in the active' guide'.'
4 uno case'be.' earlier:than June 1980.
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