ML20199H626

Safety Evaluation Accepting Classification of Instrument Air Tubing & Components for Safety Related Valve Top Works.Staff Recommends That EOI Revise Licensing Basis to Permit Incorporation of Change

ML20199H626
Person / Time
Site:	Waterford
Issue date:	01/21/1999
From:	NRC (Affiliation Not Assigned)
To:
Shared Package
ML20199H624	List: ML20199H619 ML20199H626
References
NUDOCS 9901250254
Download: ML20199H626 (2)

Text

_ _ _ _ _ . . . . _ - - -- -- -

,@ unq i p +4 UNITED STATES j

g NUCLEAR REGULATORY COMMISSION

1. WASHINGTON, D.C. 20666 4001 kg...../ l SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION i

SAFETY CLASSIFICATION OF INSTRUMENT AIR TUBING AND  ;

COMPONENTS FOR SAFETY RELATED VALVE TOP WORKS WATERFORD STEAM ELECTRIC STATION. UNIT 3 DOCKET NO. 50-382

1.0 BACKGROUND

On January 25,1989, Entergy Operations, Inc. (EOl) identified a discrepancy in the design and installation at Waterford Steam Electric Station, Unit 3 (Waterford 3) of the Instrument Air (IA) tubing that supplies the actuators of two safety injection valves. By letter dated July 3,1997, EOl stated that this discrepancy was also found for the lA tubing of all other safety-related air-operated valves required to perform a safety function. This tubing was installed under ANSI B31.1, with Seismic Category 1 tubing supports, but purchased as ASME Section til Class 2, with the exception of the hydrostatic testing requirements and inspection by an American Nuclear Insurer. According to Regulatory Guide (RG) 1.26 ANSI B31.1 is applicable only to Quality Group D (non-nuclear safety) piping and components. This tubing is therefore installed as non-nuclear safety tubing even though it is required to be designed and installed in accordance with ASME Section 111, Class 3 requirements. This represents a non-conformance with the licensing basis for Waterford 3. In letter dated July 3,1997, as supplemented by letter dated November 13,1998, EOl requested an exception to RG 1.26, which would permit classifying the lA tubing and components as ASME Section Ill, Class 3, but using ANSI B31.1 for installation.

2.0 EVALUATION In the July 3,1997, submittal, EOl indicated that, according to the guidance provided in NUREG-0800, " Standard Review Plan" (SRP) Section 3.2.2 " System Quality Group Classification," lA tubing and components are classified as Quality Group C as specified in RG 1.26, corresponding to ASME Section lli Class 3. At Waterford 3, EOl implemented the alternate safety classification of American Nuclear Society publication ANS-18.2 as an alternate to RG 1.26 for defining the quality of safety-related piping systems and components. In the staff safety evaluation report (SER) NUREG-0787, July 1981, the staff concluded that the ANS classification (Safety Classes 1,2,3 and non-nuclear safety) corresponds to the classification in RG 1.26 (Quality Groups A, B, C and D) and therefore, found the ANS-18.2 classification acceptable. ANS-18.2 thus forms part of the licensing basis for Waterford 3. The SER also stated that Safety Class 3 (Quality Group C) components were constructed in accordance with ASME Section Ill, Class 3 requirements except that the Code N-symbol stamp was not applied to these components and the third party inspection by an authorized inspection agency, as ENCLOSURE 9901250254 990121 PDR Aro s 0 9003 2 P

l

I.....

l*

l defined by ASME Section 111, was not implemented for these components. However, EOl stated that Class 3 components were purchased only from suppliers who possessed the l appropriate ASME Certificate of Authorization. The staff found this acceptable. The staff also l reviewed an alternate Waterford 3 inspection program and found it to be equivalent to that required by ASME Section 111, and was therefore, also found acceptable.

EOl reported this non-confo,mance condition to the Nuclear Regulatory Commission in Waterford 3 Licensee Event Reports (LER) 89-002-00 and 89-002-01. The root cause was attributed to incorrect procedures by the Architect Engineer during initial construction. EOI performed corrective actions, which included walkdowns of the tubing and welds, dye penetrant testing of welds and review of construction documentation and we! der qualification. EOl determined on this basis that the installed material met the requirements of ASME Section Ill, except for the hydrostatic testing requirement and inspection by an American Nuclear Insure.

EOl indicated that the design requirements of ANSI B31.1 were more conservative than those of ASME Section lil, Class 3 requirements, and therefore, concluded that this tubing may be l classified as Safety Class 3 even though the tubing design and installation are based on ANSI l B31.1.

l In the July 3,1997, submittal, EOl requested an exception to the SRP and RG 1.26.

Section 3.2.2 of the SRP states that exceptions to the quality group classifications of RG 1.26 are acceptable if justification can be demonstrated by alternate design rules based on the use of a more conservative design. EOl indicated that the instrument lines are installed according to ANSI B31.1, but that the tubing is procured to ASME Section Ill. The staff considers this justification acceptable for the lA tubing and components of safety-related valve top assemblies currently installed at Waterford 3. However, the staff has also determined that EOl's request is not justifiable for future installation of similar cornponents at Waterford 3. Therefore, for future installation or replacement of IA tubing and components of safety-related valve top assemblies at Waterford 3, the request for exception from the RG 1.26 classification is acceptable, provided the new IA tubing and components of safety-related valve top assemblies at Waterford 3 satisfy all Division 1 construction requirements, defined in American Society of Mechanical Engineers (ASME) Code Section Ill, Subarticle NCA-1110, Article NCA-9000, and Subsection ND, with the following exceptions:

1 The design may be based on the rules of ANSI B31.1, except that the tubing supports should be designed as Seismic Category 1.

2. The tubing and components may be exempted from the Authorized Nuclear Inspection requirement. '

The exception for installed components from RG 1.26 represents a non-conformance with the ASME Code and therefore, constitutes a deviation from the plant licensing commitments. The staff therefore, recommends that EOl revise its licensing basis for Waterford 3 to permit i incorporation of the change summarized above.

Principal Contributor: M. Hartzman l

! Date: January 21, 1999 I

1