WOLF CREEK GENERATING STATION – INTEGRATED INSPECTION REPORT - February 13, 2013 (Six Violations)
Six Violations, 36.5% Failures in Operator Requal Exams, Six Operator Reactivations in Question...
Green: The inspectors reviewed a self-revealing finding associated with licensed operator performance during the biennial requalification exam. Specifically, 19 of 52 operators failed at least one portion of the biennial requalification examinations. As an immediate corrective action, the licensed operators who failed any portion of the examinations were remediated (i.e., the licensed operators were retrained and successfully retested) prior to returning to shift.
The inspectors determined that the high rate of licensed operator failures constituted a performance deficiency because licensed operators are expected to operate the plant within acceptable standards of knowledge and abilities demonstrated through periodic testing.
Two licensed operators had not completed the remediation process and remained off shift at the end of the inspection period.
The finding has a cross-cutting aspect in the area of human performance associated with resources, because the licensee failed to ensure that personnel were adequately trained to assure nuclear safety. Specifically, the licensee failed to use sufficiently challenging weekly written evaluations during the weekly training cycles to assess licensed operator knowledge.
Green: The inspectors identified a non-cited violation of 10 CFR 55.53, "Conditions of License," for the failure of the licensee to ensure that licensed operators met all the conditions of their licenses in order to be considered an active watch stander. Specifically, the licensee failed to ensure that six licensed operator reactivations met the complete plant tour requirement specified in 10 CFR 55.53(f) prior to license reactivation and subsequent performance of licensed operator duties.
Failure to ensure that all authorized individuals who operate the controls of the facility met the conditions of their licenses as defined in 10 CFR 55.53 was a performance deficiency. This finding was more than minor because it was associated with the human performance attribute of the Mitigating System Cornerstone and affected the cornerstone's objective of ensuring the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, licensed operators that do not properly complete the requirements of 10 CFR 55.53(f) prior to resuming control room watchstanding duties may commit operator errors that could cause mitigating systems to fail to respond properly.
The prior similar violation occurred at Comanche Peak (NCV 05000445/2011004-02), and was determined to have very low safety significance per the last revision of NRC Manual Chapter 0609, Appendix I, because more than 20 percent of the license reactivation records reviewed contained these deficiencies.
This finding was determined to have a cross-cutting aspect in the area of human performance, associated with resources, because the licensee failed to ensure complete, accurate, and up-to-date procedures were available and adequate to assure nuclear safety. Specifically, the licensee failed to specify in a procedure what plant areas must be included to meet the requirements of a complete plant tour.
Green: The inspectors identified a non-cited violation of Technical Specification 3.4.12, "Low Temperature Overpressure Protection System," for exceeding the maximum allowed number of centrifugal charging pumps capable of injecting to the reactor coolant system during low temperature operations. Inspectors found that Wolf Creek inappropriately made a technical specification bases change that allowed a second charging pump to be capable of injection, contrary to the wording of the associated technical specification. Wolf Creek submitted a request for a technical specification interpretation. In response, the NRC’s Office of Nuclear Reactor Regulation stated that Technical Specification 3.4.12 allows one charging pump to be capable of injection during low temperature operations.
The failure to operate Wolf Creek in accordance with the technical specifications during low temperature conditions is a performance deficiency. The performance deficiency was more than minor because it impacted the Initiating Events Cornerstone objective of configuration control to limit the likelihood of those events that upset plant stability and challenge critical safety functions during shutdown as well as power operations.
Green: The inspectors identified a non-cited violation for failure to perform surveillance testing specified in Technical Specification 3.7.11, "Control Room Air Conditioning System." The activities the licensee was crediting to meet the requirement to verify heat removal capability were not adequate to meet the intent of the requirement. Specifically Wolf Creek was crediting their Generic Letter 89-13 heat exchanger reliability program actions to visually clean and inspect the condenser tubes to meet a heat exchanger performance test requirement which required measuring heat removal capability. Wolf Creek entered Surveillance Requirement 3.0.3 for the missed surveillance. Based on analyses by operations, engineering, and risk assessment personnel it was determined that reasonable expectation existed that air conditioning units SGK04A and SGK04B were still fully capable of meeting their specified safety function. Therefore, the air conditioning units were "Operable but Non-Conforming," and it was appropriate to consider the limiting condition for operation met for a delay time not to exceed the surveillance period of 18 months.
The inspectors determined that the failure to perform sufficient testing to satisfy a technical specifications surveillance requirement is a performance deficiency. The performance deficiency was more than minor because it impacted the structures, systems, and components and barrier performance attribute for the control room and auxiliary building and the Barrier Integrity Cornerstone objective to provide reasonable assurance that the radiological barrier remains functional.
1. Wolf Creek identified a violation of 10 CFR Part 50, Appendix B, Criterion V, “Instructions, Procedures, and Drawings,” for an improperly installed Swagelok fitting that resulted in emergency diesel generator A being unable to complete its mission time due to excessive jacket water leakage. The fitting caused fretting over time until a leak occurred on March 12, 2012, about 12 hours into a 24-hour surveillance run on emergency diesel generator A. A hardware failure analysis concluded that the resulting crack will grow quickly to the point of unacceptable jacket water leakage within 10-15 hours, thereafter. In this condition, so the engine was unable to meet its mission time of 7 days. The affected tubing was replaced the following day, and training was conducted for maintenance personnel. The violation is more than minor because it affects the equipment performance attribute of the Mitigating Systems Cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Using Inspection Manual Chapter 609, Appendix A, Exhibit 2, Mitigating Systems Cornerstone screening questions, Section A, the finding was determined to be of very low safety significance (Green) because the finding did not result in the emergency diesel generator being out of service for greater than its allowed outage time, and did not result in an actual loss of function of one or more trains of equipment designated as high safety-significant in accordance with the licensee’s maintenance rule program for more than 24 hours. Since the finding is of very low safety significance, was identified by Wolf Creek, and has been entered into the licensee’s corrective action program as Condition Report 50360, this violation is being treated as a non-cited violation consistent with Section 2.3.2 of the NRC Enforcement Policy.
2. Operation 3.8.1 because diesel generator A was unable to perform its safety function for its full mission time under certain conditions. The retaining pin for the fuel rack control shaft between cylinders 6 and 7 had not been installed during maintenance on December 3, 2010, and the pin had backed about half way out on February 23, 2011. If the pin came out, the fule injector for number 7 cylinder would no longer respond to governor controls and could fail to full-fuel position. The violation is more than minor because if left uncorrected it had the potential to lead to a more significant safety concern. Using Inspection Manual Chapter 0609, Appendix A, Exhibit 2, the inspectors performed a significance determination screening and determined that a more detailed risk evaluation was required because the finding potentially represented an actual loss of safety function for a single train for greater than the Technical Specification allowed outage time. The senior reactor analyst utilized the Wolf Creek plant-specific standardized plant analysis risk model, Revision 8.20, to assess the risk of this performance deficiency. Based on testing and analysis performed by the licensee, the analyst agreed that emergency diesel generator A would likely start and load given the conditions identified on February 23, 2011. Therefore, the primary risk would be from different accident initiator. The analyst determined that the change in core damage frequency for consequential loss of offsite power events with an associated failure of emergency diesel generator A was 4.0 x 10-8 over a 1-year period. This resulted in a change in core damage frequency of 8.9 x 10-9 for an 81-day exposure, or very low safety significance (Green). Since the finding is of very low safety significance, was identified by Wolf Creek, and has been entered into the licensee’s corrective action program as Condition Report s 33909 and 50360, this violation is being treated as a non-cited violation consistent with Section 2.3.2 of the NRC Enforcement Policy.
P. Bedgood, Manager, Radiation Protection
J. Broschak, Vice President, Engineering
R. Clemons, Vice President, Strategic Projects
J. Cuffe, Supervisor, Radiation Protection
D. Dees, Superintendant, Operations
T. East, Superintendent, Emergency Planning
R. Evenson, Requalification Program Supervisor
R. Flannigan, Manager, Nuclear Engineering
K. Fredrickson, Engineer, Licensing
R. Hammond, Supervisor, Regulatory Support
J. Harris, System Engineer
S. Henry, Operations Manager
R. Hobby, Licensing Engineer
S. Hossain, Engineer, System Engineering
J. Keim, Support Engineering Supervisor
R. Lane, Superintendent, Operations
M Legresley, System Engineer
M. McMullen, Technician, Engineering
C. Medinciy, Supervisor, Radiation Protection
W. Muilenburg, Licensing Engineer
M. McMullen, Design Engineer, Engineering
K. Miller, Technician Level III, Instruments and Controls
R. Murray, Simulator Supervisor
E. Ray, Manager, Training
L. Ratzlaff, Manager, Maintenance
L. Rockers, Licensing Engineer
R. Ruman, Manager, Quality
D. Russell, Operations Training Superintendent
G. Sen, Regulatory Affairs
D. Scrogum, Systems Engineer, Engineering
M. Skiles, Supervisor, Radiation Protection
R. Smith, Site Vice President
L. Solorio, Senior Engineer
R. Stumbaugh, Health Physicist III, Radiation Protection
M. Sunseri, President and Chief Executive Officer
J. Truelove, Supervisor, Chemistry
M. Westman, Assistant to Site Vice President
J. Yunk, Manager, Corrective Actions