ML101250342

Regulatory Conference Slides

ML101250342
Person / Time
Site:	Prairie Island
Issue date:	05/05/2010
From:	Xcel Energy
To:	NRC/RGN-III
References
Download: ML101250342 (23)

Text

Prairie Island Nuclear Generating Plant NRC Region III Regulatory Conference Emergency Action Level Scheme Issue May 11, 2010

Agenda

• Opening Remarks - Mark Schimmel

• Sequence of Events - Tim Blake

• Causes and Corrective Actions - Tim Blake

• Regulatory Significance - Jon Anderson

• Barriers and Operator Actions - Terry Bacon

• Summary - Mark Schimmel

• Closing Remarks - Dennis Koehl 2

Opening Remarks

• Prairie Island (PINGP) takes its obligation to protect the health and safety of the public very seriously

• Performance Deficiency

- Failure to follow and maintain in effect emergency plans which use a standard emergency classification and action level scheme

- We agree with the performance deficiency

• Causes and Corrective Actions

• Regulatory Significance 3

Sequence of Events, Causes, and Corrective Actions Tim Blake, Fleet Emergency Preparedness Manager 4

EAL Description

• Initiating Condition RA1 - Any UNPLANNED Release of Gaseous or Liquid Radioactivity to the Environment that Exceeds 200 Times the Offsite Dose Calculation Manual (ODCM) Specification for 15 Minutes or Longer

- RA1.1 - Applicable to routine release pathways, for which a discharge permit is normally prepared

- RA1.2 - Applicable to non-routine release pathways, for which a discharge permit would not normally be prepared

- RA1.3 - Confirmed sample analysis 5

Sequence of Events Timeline Decision to Rev 0 of EALs Rev 1 of Rev 3 of EALs submit by end implemented EALs Implemented of 3rd QTR implemented Wrong New EALs Submitted Picture No Justification for RA1.3 use submitted to NRC Used Ambiguous Thresholds 2004 2005 2006 2007 2008 2009 L Rollback Evaluating Evaluating Industry OE Kewaunee Point Beach withdraws Operator Wrong Picture OE submittal Feedback No Deviations Standard Wrong Picture Blue comments are missed opportunities 6

Revision 3 to EALs

• Completed in June 2009

• Note related to use of RA1.3 for offscale radiation monitors removed from Table R-1

• ALERT threshold changed to an unambiguous value for R-18

• Offsite Dose Calculation Manual alarm setpoints for R-25 and R-31 were reduced so these radiation monitors would read on scale at 200 X the alarm setpoint 7

Missed Opportunities

• Writers failed to use specific numbers for thresholds, instead used 200 X ODCM limits

• Literal application of fleet expectation for deviations

• Did not document and justify the use of EAL RA1.3 as an alternative entry into an ALERT for off scale radiation monitor readings

• Inadequate assessment of feedback and industry operating experience 8

Root Cause Evaluation

• Root Cause

- Existing procedure did not provide adequate guidance for changing EALs or EAL schemes

• Contributing Cause

- Change in standard and subsequent scope without sufficient resources

• Extent of Condition

- All extent of condition actions completed

- No other examples of the condition found

• Extent of Cause 9

Interim Actions Taken EAL scheme change to NEI 99-01, Rev 5 will not be made until procedure revisions are implemented Reviewed past 10 CFR 50.54(q) evaluations New 10 CFR 50.54(q) evaluations associated with risk significant planning standard changes require independent external reviews until the fleet procedure is revised 10

Corrective Actions Create a fleet procedure for changing EALs and EAL schemes with detailed guidance for:

- Proposed staffing levels and time allowances to develop and validate major changes

- Acceptable methods for meeting or changing EAL entry condition thresholds when the setpoint is beyond indication range

- Engineering reviews for changes requiring process indication or environmental monitoring

- Additional validation reviews

- Justification of changes in preparation for NRC submittals Revise EALs to include unambiguous threshold values 11

Regulatory Significance Jon Anderson - Regulatory Affairs Manager 12

Regulatory Significance EALs Thresholds Bases Radiation Monitors RA1.1 VALID reading on any Monitoring on R-18 effluent monitor that routine release exceeds 200 times the pathways for which alarm setpoint established a discharge permit by a current radioactivity is normally prepared discharge permit for 15 minutes or longer RA1.2 VALID reading on one or Addresses R-25 more radiation monitors monitoring on non- R-31 that exceeds 200 times routine release the alarm setpoint for 15 pathways for which minutes or longer a discharge permit is not normally prepared 13

Regulatory Significance

• R-25/31 Spent Fuel Pool Ventilation Radiation Monitors Flow Filter 14

Regulatory Significance Initiating Condition RA2 - Damage to Irradiated Fuel or Loss of Water Level that Has or Will Result in the Uncovering of Irradiated Fuel Outside the Reactor Vessel EAL Threshold Basis Radiation Monitors RA2.1 A VALID alarm on one or Addresses R-25 more of the following indication of fuel R-31 radiation monitors: uncovery or damage R-25 or R-31 Spent Fuel Pool Air Monitor (HI Alarm) 15

Regulatory Significance EALs RA 2.1 RA 1.2 Radiation R-25 R-25 Monitors R-31 R-31 ALERT HI-Alarm Setpoint 200 x Alarm Setpoint Thresholds: (6,000 CPM) (1,200,000 CPM)

Instrument 10 - 1,000,000 CPM 10 - 1,000,000 CPM Scaling:

16

Regulatory Significance Indication of Lowering R-25/R-31 Thresholds for Entering Spent Fuel Pool Level EAL RA2.1 or RA1.2 Or Damage to Irradiated 1400000 Fuel 1200000 1000000 R-25/R-31 800000 HI Alarm CPM 600000 6000 CPM 400000 RA2.1 RA1.2 200000 Declare an ALERT per RA2.1 0 HI Alarm 6000 200 x Alarm CPM Setpoint 17

Barriers and Operator Actions Terry Bacon - Operations Support Manager 18

Barriers and Operator Actions

• R-18 Waste Effluent Liquid Monitor Auto Closes at 30,000 CPM From Tanks To River R-18 CV-31256 Keylock NC CV-31841 FC NC FC Manual Valves NC C = normally closed; FC = fails in the closed position 19

Barriers and Operator Actions R-18 Permitted Liquid Valve No Discharge No Locked Closed ALERT

• Multiple process Yes and design Expected level No exceeded? No ALERT barriers are in Yes place such that Manual stop discharge No Yes ALERT the potential to No enter RA 1.1 is No Alarm setpoint Reached No ALERT extremely low Yes CV-31256 Auto Closed No ALERT Yes No Alarm Response No Procedure Actions ALERT Yes 20

Barriers and Operator Actions Tabletop Scenario

- 5 of 5 operators declared an ALERT 21

Summary Mark Schimmel, Site Vice President 22

Closing Remarks Dennis Koehl, Chief Nuclear Officer 23