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

2 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

3 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

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

5 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

Sequence of Events Timeline 6

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

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

8 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

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

10 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

11 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 Corrective Actions

12 Regulatory Significance Jon Anderson - Regulatory Affairs Manager

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

14

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

Regulatory Significance 15 EAL Threshold Basis Radiation Monitors RA2.1 A VALID alarm on one or more of the following radiation monitors:

R-25 or R-31 Spent Fuel Pool Air Monitor (HI Alarm)

Addresses indication of fuel uncovery or damage R-25 R-31 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

Regulatory Significance EALs RA 2.1 RA 1.2 Radiation Monitors R-25 R-31 R-25 R-31 HI-Alarm Setpoint (6,000 CPM)

Instrument Scaling:

10 - 1,000,000 CPM 10 - 1,000,000 CPM 200 x Alarm Setpoint (1,200,000 CPM)

ALERT Thresholds:

16

R-25/R-31 Thresholds for Entering EAL RA2.1 or RA1.2 0

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

18 Barriers and Operator Actions Terry Bacon - Operations Support Manager

19 Barriers and Operator Actions

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

20

• Multiple process and design barriers are in place such that the potential to enter RA 1.1 is extremely low Barriers and Operator Actions No ALERT Yes No No Yes No R-18 Permitted Liquid Discharge Valve Locked Closed Expected level exceeded?

Alarm setpoint Reached CV-31256 Auto Closed Alarm Response Procedure Actions Yes Yes Yes No Manual stop discharge Yes No No ALERT No ALERT No ALERT No ALERT No ALERT

21 Barriers and Operator Actions Tabletop Scenario 5 of 5 operators declared an ALERT

22 Summary Mark Schimmel, Site Vice President

23 Dennis Koehl, Chief Nuclear Officer Closing Remarks