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| Start date | Reporting criterion | Title | Event description | System | LER | |
|---|---|---|---|---|---|---|
| ENS 50309 | 25 July 2014 14:50:00 | Non | Technical Specification Violation Due to Control Room Staffing | This morning around 9:45 a.m. (CDT), a reportable occurrence under Section 1.28.f of the NSC (Nuclear Science Center) Technical Specifications was documented at the Texas A&M University Nuclear Science Center (NRC License No. R-83). The incident involved leaving the control room unstaffed by a licensed operator (Section 6.1.3.a.2 of the NSC Technical Specifications) for approximately 2.5 minutes while the 1 MW TRlGA reactor was operating at full power. The text below presents a brief description of the event: On the morning of July 25, 2014, during steady state operation at 1 MW (full power), Reactor Operator (RO) trainee (Deleted) was in the control room, along with a Senior Reactor Operator on Duty (SRO) (Deleted) and electronic technician (Deleted). Senior Reactor Operator (Deleted) and Reactor Operator (RO) (Deleted) were signed in as the operators on duty during the duration of the incident. Duty SRO and RO were elsewhere in the facility performing Operations tasks, and RO (Licensed) (Deleted) had remained in the Control Room to fulfill the requirement set forth in TS (Staffing) 6.1.3.a.2. At approximately 0948, NSC Radiation Safety Officer (RSO) (Deleted) entered the control room and requested the use of RO (Deleted) key to access a building on site. RO offered to open the building and left (control room) leaving RO trainee and electronic technician alone in the control room. At 0950, RO trainee noted that there was no licensed reactor operator in the control room. RO Trainee paged RO over the intercom and shutdown the reactor via manual SCRAM. Manager of Reactor Operations (also SRO) heard the reactor SCRAM from his office above the control room and went to the control room to investigate. (Duty) SRO was notified and immediately returned to the control room. It was determined by SROs that during the 2.5 minutes that RO was absent from the control room, the requirements outlined in Technical Specification 6.1.3.a.2 were not fulfilled. NSC Director was informed of the incident and NSC Form 590 (Unscheduled Scram Recovery Form) was filled out after the unscheduled shutdown. Manager of Reactor Operations authorized the restart of the reactor. NSC Director began implementation of Reportable Occurrence reporting procedures according to Technical Specification 1.28.f. Licensee is initiating an internal review to identify and correct any practices and/or procedures that may have systematically contributed to the environment that created this situation. Other corrective actions include the internal suspension of one reactor operator's license privileges pending satisfactory retraining. The unit response during and after the scram was normal. | ||
| ENS 49033 | 15 May 2013 03:09:00 | Non | Research Reactor Reportable Event - Control Rod Drive Mechanism Jam | This preliminary event report is in compliance with Technical Specification 6.6.2 Special Reports confirming in writing the initial report made by telephone to the USNRC Operations Center. During reactor shutdown after normal steady state operation on May 14, 2013 at 2209 CDT, shim safety 1 jammed at 30% withdrawn (70% inserted). Operators lowered the remaining rods with no other issues and after determining the reactor was shut down at 2250 CDT, operators began investigating the cause of the jam. The shutdown margin in this configuration was determined to be $2.91 (negative reactivity) with shim safety 1 jammed at 30%. The Technical Specification requirement for shutdown margin is $0.25 (negative reactivity) which meant the reactor was well within acceptable limits for shutdown. The reactor was determined to be in a safe shutdown state. During inspection a rope that was attached to an experiment was found to be caught inside the Control Rod Drive Mechanism (CRDM) for shim safety 1 about 10 feet from the surface of the pool. This caused a jam in the drive mechanism not allowing the rod to go below 29% and above 32%. A fuel handling team was assembled at 0945 CDT on 5/15/13 in order to remove the control rod assembly for shim safety 1. The rope connecting the experiment to the CRDM was cut in order to allow proper removal of the CRDM. The CRDM was successfully removed and the piece of rope caught inside the drive was removed. After further inspection of the CRDM no other issues were found and it was reinstalled into its normal position. Operability and scram time tests were performed and completed satisfactory at 1130 CDT. The fuel handling team was disbanded at 1137 CDT and the reactor was determined to be operational. At no point during this event was there any danger to the general public or Nuclear Science Center personnel. | Control Rod |