ML19332A501
| ML19332A501 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 08/22/1980 |
| From: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | Papay L SOUTHERN CALIFORNIA EDISON CO. |
| References | |
| NUDOCS 8009160184 | |
| Download: ML19332A501 (1) | |
Text
I UNITED STATES NUCLEAR REGULATORY COMMISSION
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1990 N. CALIFIRNIA CO ULEVAR)
SUITE 202. WALNUT CREEK PLAZA 4e,,*
WALNUT CREEK. CALIFORNIA 94596 August 22, 1980 Docket Hos. 50-206, 50-361, 50-362 Southern California Edison Company P. O. Box 800 2244 Walnut Grove Avenue Rosemead, California 91770 Attention:
Dr. L. T. Papay, Vice President Advanced Engineering Gentlemen:
The enclosed IE Circular No. 80-18, provides information on the details of a safety evaluation that is necessary to adequately supr,rt changes to radwaste systems. No written response is required.
Should you have any questions related to the enclosed information, please contact this office.
Sincerely, R. H. Engelken Director Enclosures :
1.
IE Circular No. 80-18 2.
Recently Issued IE Circulars cc w/ enclosures:
J. M. Curran, SCE R. Dietch, SCE Q,.,
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SSINS No.: 6830 Accession No.:
8006190038 IEC 80-18 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 August 22, 1980 IE C' aular No. 80-18: 10 CFR 50.59 SAFETY EVALUATIONS FOR CHANGES TO RADI0 ACTIVE WASTE TREATMENT SYSTEMS Dis
..s an of Circumstances:
Recent inspection efforts at operating power reactors have revealed numerous instances in which licensees have failed to perform adequate safety evaluations to support changes made to the design and/or operation of facility radioactive waste treatment systems. These safety evaluations are required by the regula-tions of 10 CFR 50.59 whenever changes are made in the facility as described i.
in the Safety Analysis Report (SAR).
The inadequacies of the evaluations have caused radiological safety hazards "
occur unidentified and therefore to remain unevaluated and uncorrected.
In two particular cases, the inadequately evaluated system changes resulted in system failures that caused an uncontrolled release of radioactivity to the environment.
In each of these situations, a proper 10 CFR 50.59 safety evalua-tion should have-identified and corrected deficiencies in the system modifica-tion and/or operation and would have prevented the inadvertent release of radioactivity.
NRC followup examination of the situation indicates that the inconsistency and/or inadequacy of licensee safety evaluations may be widespread. A wide range of opinions seems to exist among licensees as to what constitutes an appropriate 10 CFR 50.59 safety evaluation, particularly for radwaste systems.
Therefore, the following discussion and/or guidance is provided for licensee use in preparing future 10 CFR-50.59 safety evaluations to support changes in the design and/or operation of the radioactive waste treatment systems of licensed facilities.
Although the contents of this guidance are specifically directed to the radioactive waste systems,- the general principles and philosophy of the 10 CFR 50.59-safety evaluation guidance are also applicable to the facili.ty design.and operation as a whole; thus, the application of 10 CFR 50.59 should reflect a consistent approach.
Discussion:
The requirements of 10 CFR 50.59 are composed of three essential parts.
First, paragraph (a)(1) is permissive in that it allows the licensee to make changes to the facility and its operation as described in the safety Analysis Report without prior approval, provided that a change in Technical Specifica-tions is not involved or an "unreviewed safety question" does not exist.
Criteria for determining whether an "unreviewed safety question" exists are defined in paragraph ~(a)(2). -Second, paragraph (b) requires that records of ji changes made under the authority of paragraph (a)(1) be maintained.
These records are required to include a written safety evaluation that provides the
.IEC 80-18 August-22, 1980 Page 2 of 3 basis for determining whether an "unreviewed safety question" exists.
Paragraph (b) also requires a report (at least annually) of such changes to the NRC.
Third, paragraph (c) requires that proposed changes in Technical
- Specifications be submitted to the NRC as an application for license amendment.
Likewise, proposed changes to the facility.or procedures and the proposed conduct of: tests that involve an "unreviewed safety question" are required to be submitted to the NRC as an application for license amendment.
Any. proposed change to a system or procedures described in the SAR, either by text or drawings, should be reviewed by the licensee to determine whether it involves an "unreviewed safety question." Maintenance activities that do not result in a change to a system (permanent or temporary), or that replace components with replacement parts procured with the same (or equivalenti purchase specification, do not require a written safety evaluation to meet 10 CFR 50.59 requirements. However, a safety evaluation is required to meet the provisions of 10 CFR 50.59 and any change must be reported to the NRC as required by 10 CFR 50.59(b) if the followin circumstances occur: (1)com-ponent-described in the SAR are removed; (g) component functions are altered; 2
(3) sub titute components are utilized; or (4) changes remain following comple-tion of a maintenance activity.
Notice to Licensees:
For all cases requiring a written safety evaluation, the carety evaluation must set forth the bases and criteria used to determine that the poposed change does or does not involve an "unreviewed safety question." l simple statement of conclusion in itself is not sufficient.
However, dep.snding upon the significance of the change, the safety evaluation may be briaf. The scope of the evaluation must be commensurate with the potential safety significance of the proposed change or test. The depth of the evaluation must be sufficient to determine whether or not an "unreviewed safety question" is involved.
These evaluations and analyses should be reviewed and approved by an appro-priate level of management before the proposed change is made.
An important part of the "unreviewed safety question" determination is the evaluation and analysis of the proposed change by(2) corrective actions are the licensee to assure that (1) potential safety hazards are identified, and taken to eliminate, mitigate, or control the hazards to an acceptable level.
All realistic failure modes and/or malfunctions must be considered and protec-tion provided commensurate with the potential consequences. All applicable regulatory requirements, including Technical Specifications, must be complied with so that the proposed change shall not represent an "unreviewed safety question." Also, the margin of safety as defined in the bases of the Technical Specifications shall not be reduced by the proposed change.
For radioactive waste systems, the appropriate portions of 10 CFR 20, 30, 50, 71, and 100, the facility. Technical Specifications, and 40 CFR 190 (Environ-mental Dose Standard) are applicable.
Additional specific criteria that should be reviewed prior to the modification of radioactive waste systems are presented below:
-(1)) System modifications should be evaluated against the seismic, quality
_ group and quality assurance criteria in Regulatory Guide 1.143.
Design
IEC 80-18 August 22, 1980 Page 3 of 3 provisions for controlling releases of radioactive liquids, as presented in Regulatory Guide 1.143, should also be evaluated.
(2) Radiological controls should be evaluated against the criteria in Regulatory Guide 1.21 and Standard Review Plan Section 11.5, " Process and Effluent Padiological Monitoring and Sampling Systems."
-(3) Systems involving potentially explosive mixtures s:nuld be evaluated against the criteria in Standard Review Plan Section 11.3, " Gaseous Waste Management System," subsection II, item 6.
(4) System design and operation should be evaluated to assure that the radiological consequences of unexpected and uncontrolled releases of radioactivity that is stored or. transferred in a waste syster are a small fraction of the 10 CFR 100 guidelines; i.e., less than 0.5 ram whole body-dose,1.5 rem thyroid from gaseous releases, and less than the radionuclide concentrations of 10 CFR 20, Appendix B, Table II, Column 2 from liquid releases at the nearest water supplies.
(See Standard Review Plan Sections 15.7.1, 15.7.2, and 15.7.3 for more details.)
j The evaluation must include an analysis encompassing the above criteria to Oe extent that the criteria are applicable to the proposed changes; i.e., if the modifications involve a change addressed by the above regulations and criteria, then the modifications must be evaluated in tenns of these regulations and criteria.
In conclusion, for any change in a facility radioactive waste system as described in the SAR, a safety evaluation is required in accordance with 10 CFR 50.59.
In this safety evaluation and the "unreviewed safety question" determination, the evaluation criteria in Items 1-4 above should be used.
If the prcposed modification (design, operation, or test) represents a departure from'this evaluation criteria, one of the following actions should be taken:
(1) The proposal should be modified to meet the intent of the criteria; (2) The evaluation / determination must present sufficient analyses to demonstrate the acceptability of the departure; or, (3) Commission approval must be received prior to implementing the modification (i.e., an unreviewed safety issue may be involved).
No written response to this circular is required.
If additional information regarding-this subject is required, contact the Director of this office.
i
7 IEC 80-18 August 22, 1980 RECEflTLY ISSUED IE CIRCULARS Circular Date of No.
Subject Issue Issued to 80-17 Fuel Pin Damage Due to Water 7/23/80 All holders of PWR Jet from Baffle Plat: Corner OLs and PWR cps 30-16 Operational Deficiencies In 6/27/80 All power reactor Rosemount Model 510DU Trip facilities with an Units And Model 1152 Pressure OL or a CP Transmitters 80-15 Loss of Reactor Coolant Pump 6/20/80 All pcwer reactor Cooling and Natural Circula-facilities with an tion Cooldown OL or CP 80-14 Radioactive Contamination of 6/24/80 All holders of power Plant Demineralized Water and research reactor System and Resultant Internal licenses (operating Contamination of Personnel and construction permits), and fuel cycle licenstus 80-13 Grid Strap Damage in 5/18/80 All holders of reactor Westinghouse Fuel Assemblies Ots and cps 80-12 Valve-Shaft-To-Actuator Key 5/14/80 All holders of reactor May Fall Out of Place When OLs and cps Mounted Below Horizontal Axis 80-11 Emergency Diesel Generator 5/13/80 All holders of a power Lube Oil Cooler Failures reactor OL or CP 80-10 Failure to Maintain 4/29/80 All holders of reactor Environmental Qualification OLs and cps of Equipment 80-09 Problems With Plant Internal 4/28/80 All holders of a power
. Communications Systems reactor OL or CP 80-08 BWR Technical Specification 4/18/80 All General Electric Inconsistency - RPS Response BWRs holding a power Time reactor OL 80-07 Problems with HPCI Turbine 4/3/80 All holders of a power Oil System reactor OL or CP