Event Notification Report for February 28, 2021
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
02/27/2021 - 02/28/2021
EVENT NUMBERS
55359
55359
Non-Power Reactor
Event Number: 55359
Rep Org: Purdue University
Licensee: Purdue University
Region: 0
City: West Lafayette State: IN
County: Tippecanoe
License #: R-87
Agreement: N
Docket: 05000182
NRC Notified By: True Miller
HQ OPS Officer: Donald Norwood
Licensee: Purdue University
Region: 0
City: West Lafayette State: IN
County: Tippecanoe
License #: R-87
Agreement: N
Docket: 05000182
NRC Notified By: True Miller
HQ OPS Officer: Donald Norwood
Notification Date: 07/19/2021
Notification Time: 13:47 [ET]
Event Date: 02/28/2021
Event Time: 15:00 [EST]
Last Update Date: 07/19/2021
Notification Time: 13:47 [ET]
Event Date: 02/28/2021
Event Time: 15:00 [EST]
Last Update Date: 07/19/2021
Emergency Class: Non Emergency
10 CFR Section:
50.72(b)(1) - Deviation From T Spec
10 CFR Section:
50.72(b)(1) - Deviation From T Spec
Person (Organization):
Montgomery, Cindy (NPR PM)
Takacs, Michael (NPR ENC)
Montgomery, Cindy (NPR PM)
Takacs, Michael (NPR ENC)
EN Revision Imported Date: 8/19/2021
EN Revision Text: REACTOR OPERATED AT GREATER THAN 100 PERCENT TECHNICAL SPECIFICATION POWER LIMIT
"On February 28, 2021, [at approximately 1500 EST], following recalibration of the reactor power in accordance with PUR-1 Technical Specifications, the reactor operator operated the reactor at 8.5 kW (85% of nominal power) and noticed that the rate of temperature change of the coolant was greater than expected. Noting that this presents the possibility of the power being in excess of expectations, PUR-1 was shut down and has remained shut down to date. PUR-1 staff immediately notified the Committee on Reactor Operations (CORO) and developed a plan to perform an in-depth investigation.
"Since then, multiple independent assessments on the reactor power have been performed, which include: Hand calculations, Monte Carlo N-Particle code (MCNP) simulations, analysis on activity measurements of irradiated materials, a thermal-hydraulic analysis using a Computational Fluid Dynamic (CFD) model of PUR-1, and a more physical assessment using resistance heaters as heat sources to determine the coolant temperature change rate as a function of power and pool temperature, which has just been completed.
"These five independent evaluation methods performed to determine the core power during the experiment on February 28, 2021, suggest that the reactor may have been operated for about 4 hours at a power in the range between 118.3 percent to 129.2 percent of our 12 kW maximum allowable power (per TS 2.2). While the reactor was not operated outside the bounds of the Safety Analysis Report (SAR), this represents a potential need for reporting under TS 6.7.b.1.c.vi, 'An observed inadequacy in the implementation of procedural controls...'.
"Staff are currently evaluating several potential corrective actions including adjustment of the current power calibration constant, which relates the activity of the gold foil to the core power, by the most conservative factor suggested by these five analyses. There was no impact to the safety of the public or PUR-1 staff and the Safety Limit was not exceeded at any point. A formal report will be subsequently issued."
EN Revision Text: REACTOR OPERATED AT GREATER THAN 100 PERCENT TECHNICAL SPECIFICATION POWER LIMIT
"On February 28, 2021, [at approximately 1500 EST], following recalibration of the reactor power in accordance with PUR-1 Technical Specifications, the reactor operator operated the reactor at 8.5 kW (85% of nominal power) and noticed that the rate of temperature change of the coolant was greater than expected. Noting that this presents the possibility of the power being in excess of expectations, PUR-1 was shut down and has remained shut down to date. PUR-1 staff immediately notified the Committee on Reactor Operations (CORO) and developed a plan to perform an in-depth investigation.
"Since then, multiple independent assessments on the reactor power have been performed, which include: Hand calculations, Monte Carlo N-Particle code (MCNP) simulations, analysis on activity measurements of irradiated materials, a thermal-hydraulic analysis using a Computational Fluid Dynamic (CFD) model of PUR-1, and a more physical assessment using resistance heaters as heat sources to determine the coolant temperature change rate as a function of power and pool temperature, which has just been completed.
"These five independent evaluation methods performed to determine the core power during the experiment on February 28, 2021, suggest that the reactor may have been operated for about 4 hours at a power in the range between 118.3 percent to 129.2 percent of our 12 kW maximum allowable power (per TS 2.2). While the reactor was not operated outside the bounds of the Safety Analysis Report (SAR), this represents a potential need for reporting under TS 6.7.b.1.c.vi, 'An observed inadequacy in the implementation of procedural controls...'.
"Staff are currently evaluating several potential corrective actions including adjustment of the current power calibration constant, which relates the activity of the gold foil to the core power, by the most conservative factor suggested by these five analyses. There was no impact to the safety of the public or PUR-1 staff and the Safety Limit was not exceeded at any point. A formal report will be subsequently issued."