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Kenneth Thomas Interview

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Guest Name: Kenneth Thomas

Company: Nebraska Public Power District

Plant Name: Cooper Nuclear Station (CNS)

Position or Title: Mechanical Programs Supervisor

ASME Section XI/OM Code of Record: 2001 Edition, 2003 Addenda

ASME Section XI/OM Inspection Interval: 4th Interval (as of March 1, 2006)

E-Mail Address: kbthoma@nppd.com

Phone Number: (402) 825-5445


Question: How many personnel do you have in your ISI/IST organization and how are the responsibilities distributed between the ISI/NDE, Risk Informed, Pump and valve, Containment, System Pressure Test, Snubber, Repair/Replacement Programs, etc.?

Thomas: We have one Engineer who is responsible for the developing and maintaining the ISI and BWRVIP Programs, Containment Inspection Program, associated relief requests and administrative procedures. This also includes coordination of pressure tests. He is assisted by a technician who also assists the Erosion/Corrosion Engineer.

There is also one Engineer responsible for implementation of the IST Program. He develops the test procedures and reviews the test results. The System Engineer is responsible for trending.

Another Engineer is responsible for administering the repair/replacement program. He reviews the work documents and ensures that the ISI, IST, Appendix J Engineers, and ANII have reviewed the repair plans. He prepares the NIS-2 after the outage. He is also responsible for snubber testing. At CNS, we have a small population of snubbers.

We have implemented a Risk Informed (RI) program, and saw a significant savings in cost and dose in the Spring 2005 Outage.

We do not have any certified NDE technicians at our plant. We use contractors for all NDE. However, we do have several people in Engineering, Operations, and Maintenance certified to perform visual examinations.

Question: How much of the NDE is actually performed by your organization, if any, in lieu of utilizing outside vender support, and if so, what savings have you recognized by using your in-house personnel?

Thomas: No NDE is performed by CNS personnel. We only perform visual examinations. We hope to establish a certification program for PT/MT and UT Thickness testing.

Question: What changes have you made in your organizational structure or reporting functions that you have found to be beneficial?

Thomas: In order to maintain the quality and integrity of our programs, we have learned that Engineering Programs personnel must be protected from unrelated distractions. Our plant has learned that the program engineers are not interchangeable. Maintaining these programs requires dedicated personnel. They have specific knowledge and skills gained through experience working with the Code and in the plant.

Question: What issues proved to be very difficult, costly, or troublesome to resolve, and what would you recommend to avoid those issues in the future?

Thomas: There are many gray areas that are not specifically addressed in the code. When we have come to a decision, we try to document the basis for that decision. We may capture it in the database or in the program as appropriate. When we can't come to agreement amongst ourselves, we submit an inquiry to the ASME.

Question: What code cases or relief requests have you implemented that have proven to be very helpful and cost effective?

Thomas: N-460, N-526, N-552, N-586, N-597-1, N-624, N-639, N-648-1 and N-686 are included in the new 4th interval program. Relief requests tend to be plant specific and wouldn't have provided much benefit to other plants.

Question: Has your organization implemented a risk informed ISI or IST program, and if so, what Code Cases or methodology did you incorporate and what benefits and savings have you realized? What was the scope of the program and the approximate costs to develop the program? Were there any unexpected problems encountered while developing the program? Did you receive any requests for additional information from the NRC and has your program been approved?

Thomas: We used the EPRI Template, which is consistent with N-577. There were some RAIs, but they mainly were for clarification. No problems were encountered during the development. The program was approved for the third interval and is being resubmitted for approval for the fourth interval.

Question: What form of training has proven to be the most successful for your group; in-house instruction, vendor instruction, organizational instruction (EPRI, NSSS, etc.), conferences, technical meetings, online learning, etc.? What ISI/NDE training seminars are you considering for attendance in the near future?

Thomas: The EPRI NDE for Engineers has been very good. Our ISI and Erosion Corrosion Engineers have all taken it. ASME XI meetings are also instructional. We learn a lot about the basis for a specific examination at code meetings. We also get an opportunity to exchange information with our peers. The BWRVIP IVVI Training is also very beneficial for the program owners.

Question: What new NDE techniques, technology, or special NDE situations have you encountered recently and were they successful?

Thomas: We work closely with our contractor to use the best techniques available. We did have some difficulty with the Core Shroud examination tool during the last outage.

Question: Has your organization implemented the requirements for ASME Section XI, Appendix VIII, of the 1995 Edition with the 1996 Addenda. Did you utilize the recommended EPRI format for relief requests, and if so, which ones? What is the approval status of your relief requests and what problems or successes have you encountered in implementing Appendix VIII?

Thomas: In conjunction with our NDE contractor, we are implementing Appendix VIII. We did receive approval of a request for an alternative to Supplement 10 and are resubmitting it for approval in the fourth interval. The other concern we have is making sure the NDE Technicians are aware of the differences in examination requirements, particularly for Risk-Informed creviced locations.

Question: What do you find to be the most difficult part of your job?

Thomas: Coordinating ISI examinations with several other departments is the most difficult part of the job. Each group has their own priorities. We have found that by communicating our needs early and often, we get the best results. The second most difficult part is educating management on Code and BWRVIP requirements.

Question: What do you find to be the most rewarding part of your job?

Thomas: I consider ISI, BWRVIP and IST to be important methods for enhancing the safe and reliable operation of the plant. The Outage Manager may not be too happy when ISI delays startup because a flaw has been detected that has to be evaluated or repaired. But we know that we have done our job correctly by detecting the flaw.

Question: What have you found to be the most humorous experience on the job?

Thomas: Early in my career I provided a lot of explanation to an NRC inspector on how the Code worked. He became the region's expert and came back to audit me.

Question: Have you had any difficulties or questions regarding the code classification of system components or establishing the code classification boundaries? If so, what difficulties or questions did you encounter and how did you resolve the issues? What technical positions did you take?

Thomas: It isn't too difficult to establish system boundaries, but you have to have a good technical basis for them. Finding the technical basis is the challenging part. At times I have requested technical positions from Licensing or calculations from Design to justify various technical positions.

Question: Have you had any difficulties or questions applying the Section XI Repair/Replacement Rules to components, spare parts, etc. If so, what difficulties or questions did you encounter and how did you resolve the issues? What technical positions did you take?

Thomas: CNS is an older plant. Some of our equipment was not built to a specific code. It can be difficult to apply the Code rules at the part level. It requires an understanding of how the part functions in relation to the whole. It can also be difficult to determine what the original construction code requirements where after 25 years.

Question: Does your organization plan to implement a Section XI edition and/or addenda that is later than currently required in 10 CFR 50, and if so, what benefits do you anticipate?

Thomas: No, we are using the latest edition and addenda approved by the NRC. We also review any new code cases that may be beneficial to our plant.

Question: Do your NDE procedures include a methodology for calculating the examination coverage for limited examinations, and if so, how is this calculation performed and what considerations are included?

Thomas: We require the NDE contractor to address this in his procedures. The calculations consider the volume required by the code and the coverage obtained for each different angle.

Question: Does your plant share any calibration blocks on a regular basis with other plants outside of your organization, and if so, what types of blocks do you share and who do you share them with?

Thomas: We have shared some calibration materials with Fort Calhoun and have borrowed some from Duane Arnold. We have usually shared piping calibration standards.

Question: As outages become shorter and shorter, how are you able to handle your ISI workload during the outage? Are you supplementing your staff with additional temporary personnel or are some tasks getting deferred?

Thomas: We schedule pressure tests on line during system windows or scheduled IST testing. We also perform Class 2 & 3 examinations pre-outage to the extent practical. We now schedule ISI exams during both shifts of an outage. We begin planning for the next outage at least a year in advance.

Question: Has your current or prior organization ever lost accountability of their ISI/IST program due to inadequate record keeping, non-documented plant modifications, etc.? What activities were lacking that led to the situation? What efforts were required to reconcile, verify, and/or validate the database to get the program back to a state of confidence? What controls were put in place to ensure that such an incident would not occur again?

Thomas: At a previous plant, accountability was lost. We had to sort through ten-years worth of data to re-establish the examination history. We also re-performed several exams that did not meet the standards. We maintain a hard copy of exam data sheets filed by component/weld. We also input examination results into our database. We do not rely on a contractor to maintain the status of our program.

Question: What type of software do you use to track and analyze ISI program commitments and inspection data? Was the software developed by your organization or purchased from a vender? Does it adequately meet your needs? If not, why not?

Thomas: We are using the Iddeal database. IT works well for Risk-Informed applications and for Appendix VIII requirements.

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