ML20078A356
| ML20078A356 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 01/17/1995 |
| From: | Woodlan D TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20078A359 | List: |
| References | |
| TXX-95002, NUDOCS 9501240372 | |
| Download: ML20078A356 (6) | |
Text
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M Log # TXX 95002 EM File # 10010.1 L
4 905.4 (clo) 3 Ref. # 10CFR50.55a(g)
C 7UELECTRIC Januarj 17, 1995 C. Iance Terry Gesap N rmidrar t
U. S. Neclear Regulatory Commission Docurent Control Desk Washington, DC 20555 I
SUBJECT:
COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)
UNIT 2 DOCKET NO. 50 446 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION ON THE CPSES UNIT 2. FIRST TEN YEAR INSERVICE INSPECTION PROGRAM PLAN (UNIT 2: 1986 EDITION OF ASME CODE SECTION XI NO ADDENDA, INTERVAL START DATE AUGUST 3, 1993. FIRST INTERVAL)
REF:
- 1) NRC Letter from Mr. Timothy J. Polich to Mr. C. Lance Terry, dated November 9, 1994 I
Gentlemen:
l On November 15, 1994 TV Electric received a request for additional information from the NRC (Reference 1) regarding Interim Change Request (ICR) ISI-2RO 001 to the "PSES, Unit 2, Inservice Inspection (ISI) Program Plan.
ICR ISI-2RO 001 was submitted on May 31, 1994 via letter TXX 94154.
The additional information requested by the NRC is provided in the Attachment to this letter.
A current copy of the Unit 2 Augmented Inservice Inspection (AISI) Plan is provided in Enclosure 1 for your information. Future chariges and revisions to the Unit 2 AISI Plan will be available on site.
Please note that an ICR is the document used to process necessary changes prior to issuance of the next ISI Plan revision. A revision to the ISI Plan is usually issued after the completion of each refueling outage and prior to the next successive refueling outage.
ICRs and ISI Plan revisions include items such as rescheduled exams and updated drawings. A request for relief from th-ASME Code is requested separate from ICRs and Plan revisions; however, copies of relief requests are included in ICRs and Plan revisions for the purpose of administrative updates to the ISI Plan. A relief request is c..igned a unique identifier which consists of a letter representing the Code subsection followed by a sequential number (e.g., Lt 6 is assigned to the sixth request for relief from a requirement of Subsection IWB).
ICR iSI 2RO 001 did not request relief from ASME Code requirements.
0 9501240372 950117 1
1 h
00 N. Ouve I B. 81 Delles. Teams 75201
'TXX 95002 Page 2 cf 2 If'you have.any questions, please contact Mr. Ben Mays at (817) 897 6816 or Mr. Carl 8. Corbin at (214) 812 8859.
Sincerely.
C. L. Terry By:
D. R. Woodlan Docket Licensing Manager CBC/ba Attachment Enclosures c-Mr. L. J. Callan, Region IV Resident Inspector, CPSES Mr. T. J. Polich, NRR Mr. G. Bynog (TDLS)
Boyd W. Brown INEL Research Center 2151 North Boulevard P. O. Box 1625 Idaho Falls Idaho 8315 2209 1
Attachment to TXX 95002 Page 1 of 3 ITEM 2.3 Addrets the degree of compliance with augmented examinations that have been established by the NRC when added assurance of structural reliability is deemed necessary. Examples of documents that address augmented examinations that may be applicable based on licensee commitments are:
(1)
Branch Technical Position HEB 3 1, High Energy fluid Systems.
Protection Against Postulated Piping Failures in Fluid Systems Outside Containment; (2)
Reguiatory Guide 1.150 Ultrasonic Testing of Reactor Vessel Welds During Preservice and Inservice Examinations; (3)
Regu1atory Guide 1.14 Reactor Coolant Pump Flywheel Integrity.
RESPONSE
Augmented examinations established by the NRC which are applicable to CPSES are either included in the " Augmented Inservice Inspection (AISI) Plan" or addressed in the FSAR. The AISI / FSAR address the degree of compliance with applicable augmented examinations.
Item 2 a.(1): Compliance with the governing document is addressed in the Unit 2 AISI Plan. A copy of the Unit 2 AISI Plan is provided ir Enclosure 1 for your information.
Item 2.a.(2): Compliance with the governing document is addressed in FSAR Section 1A(N) (Enclosure 2).
Item 2.a.(3): See Item 2.a.(1) above.
ITEM 2.b:
Section 50.55a(g)(6)(11)(A) of Title 10 of the Code of Federal Regulations requires that all licensees must augment their reactor vessel examinations by implementing once, during the inservice inspection interval in effect on September 8, 1992, the examination requirements for reactor vessel shell welds specified in Item Bl.10 of Examination Category B A of the 1989 Code.
It is recognized that based on the effective date of the subject regulation and the August 3,1993, starting date of the first 10 year interval of the Comanche Peak Steam Electric Station, Unit 2, that the augmented requirement may not be applicable.
It is a regulatory position however, that i
essentially 100 percent of the Examination Category B A, Item Bl.10 be
{
examined. Please provide the staff with a technical discussion describing the intended approach and any specialized techniques or equipment that will be used to perform the required eeactor pressure vessel examinations.
Include an estimate on the percentage of volumetric coverage that can and will be achieved.
Attachment to TXX 95002 Page 2 of 3
RESPONSE
j 100% of the Reactor Vessel Examination Category B A, Item Bl.10 welds are included in the Unit 2 ISI Plan Section 4.1.
The required volumetric examinations will be conducted by a combination of manual and automated ultrasonic techniques from the inside and/or the outside surface. The scheduled completion of these examinations coincides with the end of the first ten year ISI interval. Greater than 90%
coverage of the required examination volume is expected.
ITEM 2.c:
C.ade Class 2 piping welds *. 'he residual heat removal, emergency core cocling, and containment heat removal systems are critical to the safe shut down of the plant.
It has been recognizeri that current Code examination nequirements exclude selection of thin wall piping welds (<3/8 inch) in the subject systems. As a result, flaws in thin wall piping welds would not be detected until through wall leakage occurs.
In the review of the licensee's program, it has oeen noted that Class 2 piping welds <3/8 inch are included in the total Class 2 piping weld population but are excluded from examinations. Considering the safety significance of the subject systems, describe your plans for volumetric examination of a sample of thin-wall piping welds to assure the continued integrity of the subject systems.
RESPONSE
To assure continued integrity of the subject systems a sample of thin wall piping welds are subject to volumetric examination as described in the Unit 2 AISI Plan. A copy of the AISI Plan is provided in for your information.
ITEM 2.d Please provide isometric and component drawings showing all Code Class 1 and Class 2 piping, welds, components, and supports. The requested isometric and component drawings, in conjunction with the schedule of examinations, will permit the staff to determine if the extent of ISI examinations meets the applicable Code requirements.
RESPONSE
Copies of isometric and component drawings showing all Code Class 1 and Class 2 pEing, welds, ccmponents and supports are provided in
' < closure 3.
ITEM 2.e.-
For Examination Category B-J, Class 1 piping welds, the Code requires that welds selected for examination shall include:
(1) all terminal ends in each pipe or branch run connected to vessels, (2) all terminal ends and joints in each pipe or branch run connected to other components where the stress levels exceed stress levels as applicable, and (3) all dissimilar metal welds.
In some cases the licensee has selected pipe to pipe welds. These types of welds are typically not selected as they are not structural discontinuities or high stress welds. Discuss the methodology used to
I I
Attachment to TXX 95002 Page 3 of 3 select Class 1 piping welds for examination.
RESPONSE
Code Class 1 piping welds are selected for examination in accordance with Table IWB 2500 1 Examination Category B J of the ASME Code. Of the six Class 1 pipe to pipe welds that.were selected for examination, four are considered high stress welds and are required to be examined per Table IWB 2500 1 Examination Category B J Note (1)(b). The remaining two pipe to pipe welds were selected for examination so that the total number of welds selected for examination equaled at least 25% of the welds in the Reactor Coolant System as discussed in Table IWB 2500 1 Examination Category B J Note (1)(d). The methodology used to select these additional welds considered size and material' distribution within the system as well as accessibility and location for ALARA purposes.
ITEM 2.f:
Verify that there are no requests for relief required at this time.
If relief requests are required, the licensee should submit them for staft review.
RESPONSE
The Unit 2 ISI Program Plan, Revision 0, was issued by TXX 93344, dated 0ctober 6, 1993. At that time no relief requests were identified: however, since that time relief requests A 1 and A 2 have been submitted and are contained in Appendix A of the Unit 2 ISI Plan.
The requests for relief were submitted via TXX-94332, dated December 21, 1994. The relief requests were added to the Unit 2 ISI Plan via Interim Change Request No.s ISI 2RO 02 and 03 (submitted via TXX-94337, dated December 21, 1994). Additional relief requests are anticipated and will be submitted when t. i extent of limitations are determined. The extent of limitations are defined at the time of examination.
i ENCLOSURE 1 TO TXX 95002
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