Regulatory Guide 3.23

Stabilization of Uranium-Thorium Milling Waste Retention Systems

ML13038A432
Person / Time
Issue date:	11/30/1974
From:	US Atomic Energy Commission (AEC)
To:
References
RG-3.023
Download: ML13038A432 (2)

40 J,

Uj4- November 1974 U.S. ATOMIC ENERGY COMMISSION

REGULATORY

DIRECTORATE OF REGULATORY STANDARDS

GUIDE

REGULATORY GUIDE 3.23 STABILIZATION OF URANIUM-THORIUM MILLING WASTE

RETENTION SYSTEMS

A. INTRODUCTION

more than 100 acres containing millions of tons of tailings. When milling operations are terminated, the waste liquids gradually evaporate or are treated and Section 20.105, "Permissible Levels of Radiation in released leaving dry solid tailings in a condition such that Unrestricted Areas," of 10 CFR Part 20, "Standards for erosion by wind is likely. Solid waste -tailings generally Protection Against Radiation," prohibits, except as contain less than 0.05 percent uranium or thorium.

authorized by the Commission pursuant to Section However, they also contain nearly all the radioactive

20. 105(a), the use of licensed materials in such a manner daughters which were initially in the ore. Average ex.

as to create in any unrestricted area, radiation levels ternal radiation levels at the surface of unstabilized which, if an individual were continuously present in the tailings piles resulting from these radioactive daughter area, could result in his receiving a dose (1) in excess of products generally exceed the 2 mr/hr external radiation two millirems in any one hour or (2) in excess of 100 limit specified in §20.105 of 10 CFR Part 20 for un- millirems in any seven consecutive days. Section 20.106, restricted areas. Furthermore, concentrations of airborne

"Concentrations in Effluents to Unrestricted Areas," radon and other radioactive materials around inactive generally prohibits the use of licensed material in such a systems may exceed the limits specified in Appendix B

manner as to release to an unrestricted area radioactive as a result of wind erosion.

material in concentrations which exceed the limits speci- V ..-

-

fied in Appendix B, Table II of Part 20. This regulatory guide describes the principal stabilization, maintenance, In order to limit exposures to individuals to external and long-term control criteria acceptable to the Regula- radiation and airborne radioactive materials to "as low as tory staff that should be considered in connection with practicable" and to prevent imprudent uses of tailings, the construction and use of tailings retention systems at such as in construction, inactive tailings systems should uranium and thorium mills containing radioactive be stabilized and controlled to limit access to the area.

materials in concentrations exceeding those specified in The stabilized system should also be examined from Appendix.B of 10 CFR Part 20. time to time on a regular frequency to ensure the integ- rity of the stabilized system. Subcommittee N46-7 of

B. DISCUSSION

American National Standards Committee N46, Nuclear Reactor Fuel Cycle, under the sponsorship of the American Institute of Chemical Engineers, has developed The milling of uranium and thorium ores results in a standard which provides general criteria on stabiliza- the production of large quantities of liquid and solid tion, control, maintenance, and inspection of inactive wastes (tailings) which contain radioactive materials in retention systems for wastes resulting from the milling of concentrations in excess of those specified in Table II of uranium and thorium ores. This standard was approved Appendix 3, 10 CFR Part 20. As these wastes are gen- by the American National Standards Committee N46 erated during milling operations, they generally are and its Secretariat. It was subsequently approved and stored in earth dam retention systems located near the designated ANSI N313-1974 by the American National mill. These systems range in size from a few acres to Standards Institute on June 20, 1974.

USAEC REGULATORY GUIDES Copie of Published guides may be obtained by request indicating the divisions desired to the US. Atomic Energy Commission, Washington, D.C. 20545, Regulatory Guides are issued to describe and make available to the public Attention: Director of Regulatory Standards. Comments and suggestions for methods acceptable to the AEC Regulatory staff of implementing specific parts of improvemenrts in these guides are encouraged and should be sent to the Secretary the Commission's regulations, to delineate techniques .bed by the staff in of the Commission. US. Atomic Energy Commission. Washington, D.C. 20545, evaluating specific problems or postulated accidents, or to provide guidance to Attention: Docketing and Senrice Section.

applicants. Regulatory Guides are not substitutes for regulations and compliance with them is not required. Methods and solutions different from those let out in The guides are issued in the following ten broad divisions:

thi guides will be acceptable if they provide a basis for the findings requisite to the issuance or continuance of a permit or license by the Commission. 1. Power Reactors

6. Products

2. Research and Test Reactors

7. Transportation

3. Fuels and Materials Facilities 8. Occupational Health Published guides will be revised periodically. asappropriate. to accnommodate 4. Environmental and Siting 9. Anjtlus, Rnvievw comnmnts and to reflect new information or experience. 5. Materials and Plant Protection 1

0. General

C. REGULA*'ORY POSITION Except in those cases in which the applicant proposes.

an alternative method for complying with specified The requirements and criteria included in ANSI portions of the Commission's regulations, the method N313-1974, "Stabilization of UraniumwThorium Milling described herein will be used in the evaluation of license Waste Retention Systems,"* on stabilization, control, applications or renewal applications filed after January maintenance, and inspection of inactive retention sys- 1, 1975.

tems for wastes resulting from the miffing of uranium and thorium ores are generally acceptable to the Regulatory If an applicant whose application for an initial license staff in determining whether satisfactory arrangements or license renewal is filed on or before January 1, 1975.

have been made by applicants and licensees for stabi- wishes to use this regulatory guide in developing sub- lizing, controlling, and maintaining inactive tailings mittals for applications, the pertinent portions of the retention systems. application will be evaluated on the basis of this guide.

D: IMPLEMENTATION

The purpose of this section is to provide information to applicants and licensees regarding the Regulatory *Copies may be obtained from the American National Standards staff's plans for utilizing this regulatory guide. Institute, Inc., 1430 Broadway, New York, New York 10018.

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