Applications for License Amendments (Generic Letter No. 86-03)
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555 February 10, 1986 TO ALL LICENSEES OF OPERATING REACTORS AND APPLICANTS FOR AN OPERATING LICENSE Gentlemen: SUBJECT: APPLICATIONS FOR LICENSE AMENDMENTS (Generic Letter 86-03) During the past year, I have evaluated the difficulties in providing timely notices in the Federal Register regarding license amendments proposed for issuance. One of the reasons for these difficulties is that too often the information called for by 10 CFR 50.91(a)(1) regarding an analysis of no significant hazards consideration using the standards of 10 CFR 50.92 is not provided with the amendment request. The enclosed discussion is for your information and guidance. Its purpose is to reduce delays in processing Federal Notices regarding license amendment requests. Included with the discussion is an example of a submittal which the staff found to contain an adequate analysis of the no significant hazards consideration. You are requested to ensure that all future amendment requests contain sufficient documentation to specifically address each factor under 10 CFR 50.92(d). An adequate submittal would include a detailed basis sufficiently comprehensive on the issue of no significant hazards consideration to permit the staff to file a timely Federal Register Notice. The staff's objective is to have most routine Federal Register Notices published within 20 working days of receipt of a license amendment request. In the event that the staff is unable to find that an adequate basis to support a finding regarding no significant hazards consideration has been provided, I have directed the Project Director to return the application so that the necessary information can be included. This will also highlight to utility management any significant problem the staff is experiencing with your amendment requests. Any such determination will be made by the staff within six working days of receipt. Your Project Manager will promptly notify you and return the amendment request accordingly. No specific response to this letter is required. Please contact your Project Manager if you have any questions. Harold R. Denton, Director Office of Nuclear Reactor Regulation Enclosure: As stated ENCLOSURE RECENT PROBLEMS WITH LICENSE AMENDMENT REQUESTS 10 CFR 50.91(a)(1) requires that licensees requesting an amendment provide an analysis "using the standards in 50.92" (the 3 factor test) about the issue of no significant hazards considerations (NSHC). Staff final determinations must also use the 3 factor test of 50.92. Proposed staff determinations may use the examples of actions which are "likely" or "not likely" to involve significant hazards considerations. These examples were provided in Enclosure 1 to Generic Letter 83-19. The basic problem with many recent license amendment requests is that the licensee does not provide an analysis using the 3 factor test. Often, all the licensee provides is a simple line assertion, copying the 3 factors, but offering no analysis. In many cases the safety assessment is brief or lacking in content such that the reader cannot conclude that the basis for the NSHC determination is in fact adequately provided in the description or in the safety assessment section. In other cases the safety assessment is written so that the reader cannot determine which part of the assessment applies to which of the three factors. A simple assertion that references an entire, fairly complex safety assessment as justification for satisfying the three factor test is not considered satisfactory. To expedite processing of your application, each of the three factors should be addressed separately for each part of the license amendment request. An assertion without appropriate analysis does not satisfy 10 CFR 50.91(a)(1). While a licensee may offer an opinion to be helpful to the staff on which example is appropriate, that is not sufficient to satisfy 50.91(a)(1) -- a licensee is not merely to suggest that it is "likely" or "unlikely" that a proposed amendment involves a significant hazards consideration -- the licensee is required to give an analysis in terms of the 3 factors. The licensee should not need examples of what is "likely" or "unlikely"; the licensee must complete a safety evaluation before submitting the proposed amendment. Thus, the licensee should know on the basis of the completed technical evaluation whether the proposed amendment increases the probability or consequences of an accident previously evaluated, creates the possibility of a new accident or reduces a safety margin. On this basis, the licensee should be able to articulate clearly the specific reasons as to whether the change is significant. Attached is an example of a submittal which the staff found to meet the above criteria. ATTACHMENT 1 Description of amendment request: The proposed amendment would modify Technical Specification 2.2.2, "Core Protection Calculator Addressable Constants"; Table 2.2-2, which provides a listing of the Type I and Type II Addressable Constants; and the associated Bases. The proposed amendment would also revise the appropriate page of the Index, delete the reference to Table 2.2-2 from Notation (9) and delete Notation (10) of Table 4.3-1, and delete the note in Administrative Control 6.8.1 (g). The addressable constants of the Core Protection Calculators (CPC) provide a mechanism to incorporate reload dependent parameters and calibration constants to the CPC software so that the CPC core model is maintained current with changing core configurations and operating characteristics. As a method to avoid gross errors upon operator entry of an addressable constant, a reasonability check requirement was imposed by the original NRC CPC Review Task Force. The CPC software has been designed with automatic acceptable input checks against limits that are specified by the CPC functional design specifications. Therefore, inclusion of the addressable constants and the software limit values in the Technical Specifications (2.2.2 and Table 2.2-2) is redundant, and serves only to enforce prior approval of changes to these limits. Proper administrative control procedures are available to assure that appropriate values of addressable constants are entered by the operator. Any CPC software changes involving addressable constants or software limit values are made and tested under NRC approved software change procedures and are available for NRC review. BASIS FOR NO SIGNIFICANT HAZARDS DETERMINATION: The proposed change does not involve a significant hazards consideration because operation of Arkansas Nuclear One Unit 2 in accordance with this change would not: (1) involve a significant increase in the probability or consequences an accident previously evaluated. This change merely eliminates redundant administrative requirements concerning the CPC addressable constants. The function of these requirements is already implemented by the allowable value checks in the CPC software. Changes to the addressable constants are accomplished through strict administrative procedures. Therefore, this change cannot increase the probability or consequences of an accident. (2) create the possibility of a new or different kind of accident from any previously analyzed. It has been determined that a new or different kind of accident will not be possible due to this change. This elimination of redundant administrative requirements does not create the possibility of a new or different kind of accident. (3) involve a significant reduction in a margin of safety. Administrative procedures involving the CPC addressable constants ensure that the CPC core model is calibrated to current plant conditions and therefore preserve the margin of safety. Elimination of redundant administrative requirements will not reduce the margin of safety. . The Commission has provided guidance concerning the application of the standards for determining whether a significant hazards consideration exists by providing certain examples (48 FR 14870) of amendments that are considered not likely to involve significant hazards consideration. Example (i) relates to a purely administrative change to Technical Specifications: for example, a change to achieve consistency throughout the Technical Specifications, correction of an error, or a change in nomenclature. Example (iv) relates to a relief granted upon demonstration of acceptable operation from an operating restriction that was imposed because acceptable operation was not yet demonstrated. This assumes that the operating restriction and the criteria to be applied to a request for relief have been established in a prior review and that it is justified in a satisfactory way that the criteria have been met. In this case, the proposed change described above is similar to both Example (i) and Example (iv) in that deletion of Technical Specification 2.2.2, Table 2.2-2 and modifications to the related pages are purely administrative changes, and are also relief granted upon demonstration of acceptable operation from an operating restriction that was imposed because acceptable operation was not yet demonstrated. Conceptually, the addressable constants reasonability checks are the equivalent of the limits of an adjustable potentiometer in the conventional analog hard-wired type protection system. The limits of these potentiometers are not specified in the Technical Specifications, as this would be unrealistic and would make no contribution to plant safety. The addressable constants are basically calibration constants which are used to assure that the CPC calculations of core parameters accurately reflect actual plant conditions. The proposed change may therefore be considered to achieve consistency throughout the Technical Specifications in that it removes a listing of calibration constants which is redundant in purpose and is not provided for any other system. Removal of the listing of the addressable constants (and the allowable ranges of the Type I constants) may be considered a relief from an operating restriction that was imposed by the NRC CPC Review Task Force because acceptable operation was not yet demonstrated. ANO-2 was the first CE plant equipped with the CPC system; the addressable constants Technical Specification was imposed because this system was the first application of a digital computer based portion of a reactor protection system. Subsequent operational experience with the CPC system, both at ANO-2 and the other CPC equipped plants, has demonstrated acceptable operation. Relief from this administrative restriction has been allowed after several meetings between the utilities with CPC equipped plants and the NRC Core Performance Branch, which included members of the CPC Review Task Force. The criteria applied to the relief from this operating restriction have been established and there is satisfactory justification that they have been met. The NRC Core Performance Branch have issued a draft Safety Evaluation Report (concerning the removal of the addressable constants Technical Specification) which provides this justification. Therefore, based on the above considerations, AP&L has determined that this change does not involve a significant hazards consideration.
Page Last Reviewed/Updated Tuesday, March 09, 2021
Page Last Reviewed/Updated Tuesday, March 09, 2021