Thursday, April 23, 2015

Brunswick NRC Inspectors Finding DG Day Tank Vent Pipe Violation Like Waterford?

So we are now heading towards a 2.206 on Waterford...(The 2.206 was going to be about missing missile protection on the DG day tank. I just found the NRC identified it on their CDBI inspection. So now the 2.206 is unnecessary.)

Does Waterford have tornado protection on day tank vent lines?
Roof- both A and B
dg fan-B
Dam CDBI- Specifically, between October 8 and 16, 2014, the licensee failed to initiate a condition report to evaluate the lack of missile protection on the emergency diesel generator A and B storage tank vents, a nonconformance that is a condition adverse to quality. In response to this issue, the licensee performed an operability determination to address the team’s concerns and initiated a separate condition report to document the failure to initiate a report for a condition adverse to quality.
So I am not going to have the issue Brunswick got a violation over not missile shields and the NRC ignored it in Waterford.
Bottom line, with the absent missile shield on the day tank vent lines, the DG vent fan being inop since the bugled maintenance on the B in 1999 and the corrosion on the dg day tank vent lines...the operability of the the diesel generators was impaired on multiple causes for decades. The NRC paper whips these guys on the isolated issues, they don't look at these things holistically, with  poor maintenance over multiple issue has cast a terrible possible reliability problem over both diesel generators. Basically thy don't hit Entergy with a big enough hammer to get they to globally change their tune.
You notice post CDBI missile protection finding they have picked it up at another plant-Brunswick. After all these years, why hasn't the NRC caught the divergent from licencing condition across multiple plants. Why is the industry so lackadaisical  with maintaining their original licencing conditions.
Waterford on the broken DG  fan picked up by luck, they weren't positively monitoring the DG ventilation flow...they by procedure didn't have a positive way to immediately detect a DG fan was broken.  
Bottom line, I doubt the NRC knows the totality of all the broken or degraded safety components and the deficiencies in the plant's organization at WaterFord...it is very worrisome. 
Just saying, the probability of tornado winds capable of damaging the DG day tank vent piping is not transparent.
No extent of condition with is the site within the plant design on severe weather.
I still say heavy winds could drive up debris onto the roof above the DG day tank and clog up the roof drain?  
I still say the adequate punishment would have been, you need to assume that the NRC didn't catch this, Waterford was incapable of catching it. The assumption should have been in some future both vent pipes would have rotted through, or tornado or hurricane winds would have picked up missile debris knocking off the badly corroded vent pipe...in a hurricane with a LOOP WaterFord would have lost both DGs on water intrusion into the day tank and been in a blackout. It should have been a red finding.

The worst this to do in plant accident is to tie the hands of the operators around their back...have degraded or broken equipment show up way down the EOPs. 

What you see on the big picture, the NRC has to bail them out with violations or exemptions, equipment fails over poor maintenance...Waterford can't catch problems on their own before accidents and failed equipment shows up.
As an interim action, a stainless steel pipe clamp with a rubber liner was installed around EDG Feed Tank
vent pipe to prevent water intrusion

http://www.tornadohistoryproject.com/tornado/Louisiana/map

Tornadoes in Louisiana

Date(s) (yyyy-mm-dd)TornadoesFatalitiesHighest FatalitiesInjuriesHighest InjuriesLongest PathWidest Path
1950-02-12 - 2013-12-211827206 people47 people3339 people510 people234.7 miles3080 yards

Mike, so is there a difference between a day tank ventilation piping (Brunswick) and a day tank vent pipe (Waterford). They both fill of the Diesel Generator day tank and could take out the DG.

They really never mention specifically the DG  fuel oil. Bastards.

With ventilation you are usually talking moving air, bigger pipes and a motorized fan???

I am calling vent piping and ventilation piping the same...

Waterford's DG day tank vent pipe fiasco:
January 22, 2015 WATERFORD – NRC COMPONENT DESIGN BASES INSPECTION REPORT 05000382/2014007 AND PRELIMINARY GREATER THAN GREEN FINDING
 April 09, 2015: WATERFORD UNIT 3 – NRC SUPPLEMENTAL INSPECTION REPORT 05000382/2015010
See how incredibly erratic the NRC is with violating a plant. Two plants with NRC inspectors finding issues of the possible unreliability of the diesel generators that the plant staff's didn't find.

So Waterford repaired the corroded DG vent piping with rubber and hose clamp...how can that stand up to a tornado. Why didn't the NRC inspectors violate Waterford on tornado protection like Brunswick?

Introduction. The NRC identified a Green NCV of 10 CFR Part 50, Appendix B, Criterion III,
Design Control, for failure to ensure adequate tornado missile protection for the EDG 4-day
Actually this is the first mention of fuel oil tank...I am certain its the vent line. Well, 99.5% certain.
fuel oil tank ventilation piping.
Description. On May 8, 2014, during a walkdown, the inspectors noted that the EDG 4-day fuel oil tank ventilation piping was not protected from tornado-borne missiles. The inspectors questioned the licensee on the whether this piping needed to be tornado protected, and if so, could it withstand the design basis tornado and rain event. On August 14, 2014, under WO 13421302, the licensee took corrective actions to place concrete blocks around the ventilation piping. An engineering evaluation was then performed that identified the worst case design basis tornado and rainfall scenario conditions and what effect those would have on EDG operation. It was determined that with the maximum 24-hour rainfall rate and a tornado missile shearing the ventilation piping at the roof level, the worst case scenario was the EDG1 4-day tank filling with Water  which would be transferred over to the EDG1 saddle tank. The saddle tank would fill to a level high enough to impact EDG operation in less than two hours. Following this evaluation, the licensee completed engineering change (EC) 96860 to install concrete barrier pads around the ventilation piping at the 4-day tank roof level to preclude a tornado missile impact at the most vulnerable part of the piping, and also preclude water accumulation on the roof from entering the EDG 4-day tanks. The inspectors reviewed the engineering evaluation, EC, and interviewed engineering personnel to understand the scenario and the impact to plant operation.
The Brunswick Original Final Safety Analysis Report (Appendix F) and Updated Final Safety Analysis Report (UFSAR), Chapter 3, contain the language of the regulatory requirements for the general design criteria listed in 10 CFR Part 50, Appendix A, and how the licensee complies with those criteria. Criterion 2 for protection against natural phenomena states, in part, that structures, systems, and components (SSCs) important to safety shall be designed to withstand the effects of natural phenomena such as earthquakes, tornadoes, hurricanes, floods, tsunami, and seiches without loss of capability to perform their safety functions. The licensee’s statement of compliance states, “SSCs important to safety have been designed with appropriate margin for uncertainties, to permit safe plant operation or shutdown even under conditions of the most severe natural phenomena which have been conservatively postulated to occur at the site.” Criterion 4 for missile design bases states, in part, that SSCs important to safety shall be appropriately protected against dynamic effects, including the effects of missiles, which may result from events and conditions outside the nuclear power unit. The licensee’s statement of compliance states, “SSCs important to safety have been designed with full consideration of the combined effects of the normal and postulated accident environment, including the effects of pipe whipping or other dynamic effects resulting from the accidents.” Section 3.5.1.4 of the UFSAR contains the specific analysis of four potential tornado-borne missiles and the effects on the plant. The impact of one of these missiles, shearing the EDG 4-day fuel oil tank ventilation line, along with water intrusion into the system from the design basis rainfall event, would prevent the EDG (an SSC important to safety) from performing its required safety function of providing a reliable source of AC power to the engineered safety features for safe shutdown of the plant or during design basis accidents.

Analysis. The inspectors determined the failure to ensure adequate tornado missile protection
There is the first mention of a fuel tank
for the EDG 4-day fuel oil tank ventilation piping was a performance deficiency that warranted a significance determination. The inspectors determined that the finding was more than minor in accordance with IMC 0612, “Power Reactor Inspection Reports,” Appendix B, “Issue Screening,” dated September 7, 2012, because it is associated with the Mitigating Systems Cornerstone attributes of Protection Against External Factors and Equipment Performance, and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, it was determined that the ventilation piping could be sheared with a design basis tornado missile at the 4-day fuel oil tank building roof level and water intrusion into the EDG fuel oil system would occur during a design basis rain event that would prevent the EDG from performing its required safety function. Using IMC 0609, Appendix A, issued June 19, 2012, The Significance Determination Process (SDP) for Findings At-Power, the inspectors determined the finding screened to a detailed risk evaluation since the EDG1 fuel oil system was assumed to be completely failed due to a tornado, and it would degrade one or more trains of a system that supports a risk significant system or function. The regional Senior Reactor Analyst performed a detailed risk evaluation by using a qualitative screening analysis to determine the significance of the finding. Tornado initiating event frequency was derived from Nation Weather Service data. Because of the low likelihood of a tornado powerful enough to throw an object of sufficient size to damage the piping, the remote chance the thrown object would strike the vent
Sounds like Fukushima reasoning...
pipe, and because the remaining EDGs would not be impacted in the same way by the tornado, the finding was determined to be Green. The inspectors did not identify a cross-cutting aspect associated with this finding because the finding is an old design issue that has been in place since original plant construction.
Enforcement: Title 10 CFR Part 50, Appendix B, Criterion III, “Design Control,” requires, in part, that measures be established to assure that applicable regulatory requirements and the design basis, as defined in Part 50.2 and as specified in the license application, for those structures, systems, and components to which this appendix applies, are correctly translated into specifications, drawings, procedures, and instructions.
Contrary to the above, since the initial construction of both units, until August 14, 2014, the licensee failed to translate the appropriate tornado missile protection requirements into the design of the EDG 4-day fuel oil tank ventilation piping. The licensee performed corrective actions to install concrete blocks around the tank ventilation piping. This violation is being treated as an NCV, consistent with Section 2.3.2.a of the Enforcement

Policy. The violation was entered into the licensee’s CAP as CR 686589. (NCV 05000324; 325/2014005-01, Failure to Protect Emergency Diesel Generator 4-Day Fuel Oil Tank Ventilation Piping from Tornado Missiles) 1R18 Plant Modifications (71111.18 – 1
Waterford
January 22, 2015 WATERFORD – NRC COMPONENT DESIGN BASES INSPECTION REPORT 05000382/2014007 AND PRELIMINARY GREATER THAN GREEN FINDING











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