Palisades's Update Over Cracked Primary Coolant Pumps Blades

1)

PALISADES NUCLEAR PLANT NRC INTEGRATED INSPECTION REPORT 05000255/2015002

Annual Follow-Up of Selected Issues: Primary Coolant Pump Operation

a. Inspection Scope 

The operation of the primary coolant pumps (PCPs) in a manner that resulted in flow cavitation was the subject of an NRC-identified NCV documented in Section 1R15 of Palisades IR 2012003. The inspectors continued their review of licensee corrective actions to address the NCV this quarter. The licensee, in conjunction with Westinghouse, performed a detailed analysis and system model of the operation of the PCPs during startup and shutdown conditions to evaluate the operating limits and site procedures for the pumps. This analysis was intended to determine if a nexus existed between certain plant operating conditions and PCP performance issues that had been identified.

Sounds like a half ass scientific experiment...not the necessary nuclear safety.   

From this analysis, it was determined that the way in which the PCPs were started and operated during plant startups could cause the pumps to operate

I  don't like the word "could" in this...where is the certainty they discovered the cause and fixed it? 

outside the manufacturer’s design conditions for a prolonged period of time (this was the subject of the documented NCV from 2012). Recommendations were made to consider revising the system operating procedures for sequencing pump operation during these conditions and also to re-evaluate TS limitations that may be limiting the combination of pumps that could be operated together. The TS limitations could also affect the alignments of pumps operated during plant shutdowns. The licensee assessed these recommendations, as well as others discussed in the analysis and entered the issues into the CAP. The inspectors reviewed these corrective actions which were intended to revise the system operating procedures and assess the feasibility of a TS change. There were also corrective actions to inspect the ‘B’ PCP, which was the only pump remaining to have a refurbished impeller

Any pump amp of flow perturbations yet?  

potentially with missing pieces. This inspection was planned for RFO 25 in the spring of 2017.

2) More issues with protecting their employees over radiation protects troubles.

Sounds like big backsliding issues with the CAP post yellow finding. Looking forward to the upcoming rupture.  

 Corrective Action Program 

The inspectors reviewed CRs, causal evaluations, corrective actions, and plant health committee meeting minutes associated with improving equipment reliability and system health. The inspectors also conducted an independent search of CRs to identify significant equipment issues that occurred between January 2013 and June 2015 to determine if commonalities existed with respect to causes or organizational and programmatic components related to the issues. A trend identified by external assessors this quarter was that even though the site’s equipment reliability index value was high, there were challenges to systems important to safety, some of which were long-standing or were not appropriately assessed for risk. A potential contributing factor to this was identified by a different external assessment at the end of 2014 in which engineering rigor to troubleshoot and address consequential equipment failures was not always sufficient. The inspectors had developed a similar trend based on inspection findings and observations over the same time period.

Some significant equipment failures with certain organizational and programmatic components were assessed in a common cause analysis that determined commonalities between the issues related to inadequate task barriers, insufficient detail in work packages, inadequate challenges across organizations to identify risk, and inadequate interface among organizations. The inspectors’ independent review of CRs identified additional equipment failures that were not assessed in the common cause analysis. These equipment issues had commonalities of inadequate preventive maintenance/job scopes, inadequate parts or age-related parts failures, programmatic/process weaknesses, and improper risk recognition that contributed to insufficient troubleshooting or corrective actions to prevent repeat failures. Also, some of these issues did not have definitive causes and were long-standing issues without resolution due to not identifying causes. In a few cases these issues had been repeat failures. More extensive troubleshooting was planned in the future for most of these issues, but they remained vulnerabilities until adequately corrected with the causes appropriately addressed. There were also corrective actions open to address deficiencies in these areas that had not yet been fully implemented. However, a combination of the aforementioned issues had led to equipment problems challenging systems important to safety.

The licensee recently focused on improving equipment reliability by more effectively utilizing the Plant Health Committee and decreasing the backlog of critical equipment repairs required. Systems in Maintenance Rule (a)(1) status have been discussed on a more frequent basis and WOs to repair long-standing issues were being tracked at every meeting. Emergent station concerns were also discussed. The committee had re-focused station leadership attention on risk-significant system and component issues to further inter-organizational teamwork to resolve issues in a more timely fashion.