Regulatory Guide 3.70

Use of Fixed Neutron Absorbers at Fuels and Materials Facilities.

ML12220A069
Person / Time
Issue date:	08/31/1997
From:	Office of Nuclear Regulatory Research
To:
References
DG-3011 RG-3.070
Download: ML12220A069 (4)

U.S. NUCLEAR REGULATORY COMMISSIONREGULATORYAugust 1997GUIDEOFFICE OF NUCLEAR REGULATORY RESEARCHREGULATORY GUIDE 3.70(Draft issued as DG-3011)USE OF FIXED NEUTRON ABSORBERS ATFUELS AND MATERIALS FACILITIES

A. INTRODUCTION

In 10 CFR Part 70, "Domestic Licensing of SpecialNuclear Material," Section 70.22, "Contents of Ap-plications," requires that applications for a specificlicense to own, acquire, deliver, receive, possess, use,or initially transfer special nuclear material containproposed procedures to avoid criticality accidents. Thisregulatory guide provides guidance for complying withthis portion of the Commission's regulations by de-scribing procedures for preventing criticality accidentsby using fixed neutron absorbers in operations involv-ing handling, processing, storing, and transporting spe-cial nuclear material at fuels and materials facilities.The information collections contained in this regu-latory guide are covered by the requirements of 10 CFRPart 70, which were approved by the Office of Manage-ment and Budget, approval number 3150-0009. TheNRC may not conduct or sponsor, and a person is notrequired to respond to, a collection of information un-less it displays a currently valid OMB control number.

B. DISCUSSION

ANSI/ANS-8.21-1995, "Use of Fixed NeutronAbsorbers in Nuclear Facilities Outside Reactors,"11Copies may be obtained from the American Nuclear Society, 555 N.Kensington Avenue, La Grange Park, Illinois 60525.was prepared by Subcommittee ANS-8, FissionableMaterials Outside Reactors, of the American NuclearSociety Standards Committee. ANSI/ANS-8.21-1995was approved by the American National StandardsCommittee N16, Nuclear Criticality Safety, and by theAmerican National Standards Institute (ANSI) in 1995.ANSI/ANS-8.21-1995 provides guidance forusing fixed neutron absorbers as an integral part of op-erations to prevent criticality accidents in operations in-volving handling, processing, storing, and transportingspecial nuclear materials at fuels and materials facili-ties. The design, safety evaluations, and verificationand inspection requirements for the use of fixed neutronabsorbers for criticality safety control are specified inthe standard.The methods described in this guide were appliedto a number of specific cases during reviews andselected licensing actions. These methods reflect thelatest general NRC approach to criticality safety in op-erations involving the use of fixed neutron absorbers atfuels and materials facilities.

C. REGULATORY POSITION

ANSI/ANS-8.21-1995, "Use of Fixed NeutronAbsorbers in Nuclear Facilities Outside Reactors," pro-vides procedures acceptable to the NRC staff for the useof fixed neutron absorbers in handling, processing,USNRC REGULATORY GUIDES The guides are issued in the following ten broad divisions:Regulatory Guides are issued to describe and make available to the public such informa-tion as methods acceptable to the NRC staff for implementing specific parts of the Corn- 1. Power Reactors 6. Productsmission's regulations, techniques used by the staff in evaluating specific problems or pos- 2. Research and Test Reactors 7. Transportationtutated accidents, and data needed by the NRC staff in its review of applications for per- 3. Fuels and Materials Facilities 8. Occupational Healthmits and licenses. Regulatory guides are not substitutes for regulations, and compliance 4. Environmental and Siting -9. Antitrust and Financial Reviewwith them is not required. Methods and solutions different from those set out in the guides 5. Materials and Plant Protection 10. Generalwill be acceptable if they provide a basis for the findings requisite to the issuance or con-tinuance of a permit or license by the Commission.Single copies of regulatory guides may be obtained free of charge bywriting the Printing.This guide was issued after consideration of comments received from the public. Corn- Graphics and Distribution Branch, Office of Administration, U.S. Nuclear Regulatory Com-ments and suggestions for improvements inthese guides are encouraged atall times, and mission, Washington, DC 20555-0001; or by fax at (301)415-5272.guides will be revised, as appropriate, to accommodate comments and to reflect new in-formation or experience. Issued guides may also be purchased from the National Technical Information Service onWritten comments may be submitted to the Rules Review and Directives Branch, DFIPS, a standing order basis. Details on this service may be obtained by writing NTIS, 5285 PortADM, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001. Royal Road, Springfield, VA 2216 storing, and transporting special nuclear material atfuels and materials facilities to avoid criticality acci-dents. Use of ANSI/ANS-8.21-1995, however, is not asubstitute for the licensee's preparation of and NRC'sapproval of detailed nuclear criticality safety analysesfor specific operations.Section 6 of ANSI/ANS-8.21-1995 lists addition-al documents referred to in the standard. The specificapplicability and acceptability of three of these listeddocuments has been addressed in the latest version ofthe regulatory guides identified below.Standard Regulatory GuideANSI/ANS-8.1-1983 3.4 Nuclear Criticality Safety in Operations with FissionableMaterials at Fuels and Materials FacilitiesANSI/ANS-8.5-1986 3.1 Use of Borosilicate-Glass Raschig Rings as a Neutron Absorberin Solutions of Fissile MaterialANSI/ANS-8.17-1984 3.58 Criticality Safety for Handling, Storing, and Transporting LWRFuel at Fuels and Materials Facilities

D. IMPLEMENTATION

The purpose of this section is to provide informa-tion to applicants and licensees regarding the NRCstaff's plans for using this regulatory guide.Except in those cases in which the applicant pro-poses an acceptable alternative method for complyingwith specified portions of the NRC's regulations, themethods in this guide will be used in the evaluation ofsubmittals in connection with license applications sub-mitted under 10 CFR Part 70.3.70-2 REGULATORY ANALYSISThis regulatory guide endorses ANSI/ANS-8.21-1995, "Use of Fixed Neutron Absorbers inNuclear Facilities Outside Reactors." Issuing this regu-latory guide is consistent with the NRC policy of evalu-ating the latest national consensus standards in terms oftheir suitability for endorsement by regulatory guide.The methods described in this guide were applied to anumber of specific cases during reviews and selected li-censing actions. These methods reflect the latest gener-al NRC approach to criticality safety in operations in-volving the use of fixed neutron absorbers at fuels andmaterials facilities.The value to NRC operations and industry is thatthere would be (1) a systematic method for specifyingand reviewing technical specifications on allowablefixed neutron absorbers, (2) more established methodsfor specifying technical specifications, (3) guidance ondesign, evaluation, verification, and inspection of fixedneutron absorbers, and (4) less chance for unwarrantedcriticality accidents.ANSI/ANS-8.21-1995, "Use of Fixed NeutronAbsorbers in Nuclear Facilities Outside Reactors," pro-vides more specific guidance on establishing and usingfixed neutron absorbers. It does not provide any newmethodology for establishing the use of fixed neutronabsorbers than is presently required in 10 CFR Part 70.Thus, the incremental cost should be negligible (or atmost marginal) if an applicant or licensee follows theguidance in ANSI/ANS-8.21-1995 as opposed to notfollowing this standard.3.70-3 FIRST CLASS MAILPOSTAGE AND FEES PAIDUSNRCPERMIT NO. G-67OFFICIAL BUSINESSPENALTY FOR PRIVATE USE, $300PRINTED ON RECYCLED PAPER