Monday, April 03, 2017

Junk Brown's Ferry Safety Relief Valves: Humongus Example of Inconsistent Enforcement with NRC's Regulations

It's call insanity.

What is the big deal here with two SRVs being inop this cycle, while Hope Creek I believe last outage, having something like 12 of 13 SRVs being inop. Why does the three SRV plant get a pressure setpoint drift violation, while the 12 of 13 SRV valve violations plant gets nothing but approval.

I am almost certain if the platinum seats were installed correctly it would make no difference. 

Hope Creeks's SRVs pressure test drift has been in violation of tech spec for a decade and the number of failed valve test has been ramping up till 12/ 13 failed this period. How does this make since?

Repeated events should require a escalated violation level and the number of valves failing per test should required another increase in a violation level.

A plant being in violation of tech specs requiring a immediate safety shutdown repeatedly and it's only a non cited wonder a large number of employees are in a deep state of disillusionment with the industry.

Risk perspectives makes following tech specs voluntary...    
November 9, 2016 
SUBJECT: BROWNS FERRY NUCLEAR PLANT - NRC INTEGRATED INSPECTION REPORT 05000259/2016003, 05000260/2016003, AND 05000296/2016003

Closed) LER 050000296/2016-004-00, Main Steam Relief Valves Lift Settings Outside of Technical Specification Required Setpoints
a. Inspection Scope
On April 6, 2016, the Tennessee Valley Authority was presented with as-found testing results from NTS Huntsville indicating that three of the thirteen Main Steam Relief Valves (MSRVs) from Browns Ferry Nuclear, Unit 3, exceeded the +/- 3 percent setpoint required for their operability. TS 3.4.3 required twelve of the thirteen MSRVs to be operable for MSRV system operability. The inspectors reviewed the licensee event report associated with this event and determined that the report adequately documented the summary of the event including the cause of the event and potential safety consequences. The residents reviewed the licensee’s corrective actions and associated analysis for this recurring issue. This LER is closed.
b. Findings
Introduction: A self-revealing Green Non-cited Violation (NCV) of TS 3.4.3, Safety Relief Valves was identified for two required Main Steam Relief Valves (MSRV) being inoperable longer than allowed by Technical Specifications.
Description: Browns Ferry has thirteen MSRVs per unit of which twelve are required to be operable in Modes 1, 2, and 3. The MSRVs ensure that the maximum reactor vessel pressure is not exceeded. Every refueling outage, all thirteen MSRV pilot valves are replaced with ones that have been refurbished. The as-found technical specification required surveillance testing results indicated that three of the thirteen MSRVs from Browns Ferry Nuclear, Unit 3, exceeded the +/- 3 percent band around the setpoint. Any MSRV exceeding the +/- 3 percent band results in that MSRV being declared inoperable. Troubleshooting determined that the MSRV pilot valve discs failed by corrosion bonding to their valve seats. The valve discs were previously platinum coated to prevent this, but the valve seat's rough Stellite surface caused the coating to flake off. TVA determined that the MSRVs were inoperable from March 19, 2014 to February 20, 2016. Upon further analysis, the affected valves remained capable of maintaining reactor pressure within ASME code limits. The valves' ability to open by remote-manual operation, activation through the Automatic Depressurization System, and MSRV\ Automatic Actuation Logics were not affected. The system remained capable of performing its required safety function. TVA’s corrective actions were to replace all Unit 3 MSRV pilot valves, to analyze the pilot valves of the inoperable MSRVs, and to revise procedures to verify the pilot disc finish meets its requirements prior to valve assembly. MSRV operability was restored on March 28, 2016, during the scheduled replacement of the MSRVs with refurbished valves which were certified to lift within the technical specification required setpoint limits.
Analysis: The licensee’s failure to maintain operability of the MSRVs was a performance deficiency. Two of the twelve required MSRVs were determined to be inoperable during testing following the Unit 3 refueling outage. The performance deficiency was more than minor because it adversely affected the mitigating systems cornerstone attribute of equipment performance. Specifically, two required MSRVs were not able to lift within their required pressure band. This performance deficiency was screened using IMC 0609, Appendix A, Exhibit 2, Mitigating Systems Screening Questions, dated June 19, 2012. This performance deficiency screened to Green because although the system was inoperable for greater than its allowed outage time and follow on action completion time, the system maintained its function. The inspectors assigned a cross cutting aspect of Resolution since the licensee has not taken sufficient corrective actions to address the continued out of tolerance lift results caused by corrosion bonding of the MSRV pilot valve seats. (P.3)
Enforcement: Technical Specification 3.4.3 required, in part, that 12 MSRVs be operable while in Modes 1, 2, and 3 and that if one required MSRV is inoperable that the Unit be placed in Mode 3 in 12 hours and Mode 4 in 36 hours. Contrary to the above, from March 19, 2014 to February 20, 2016, Browns Ferry Unit 3 operated in Mode 1 with more than one required MSRV inoperable and did not enter Mode 3 within 12 hours and Mode 4 in 36 hours. The licensee’s immediate corrective action was to replace all Unit 3 MSRV pilot valves prior to the completion of the refueling outage. This violation is being treated as an NCV, consistent with section 2.3.2 of the Enforcement Policy. The violation was entered into the licensee’s corrective action program as CR 1157981. (NCV)

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