05000443/LER-2001-001

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LER-2001-001,
Docket Number
Event date:
Report date:
Reporting criterion: 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
4432001001R00 - NRC Website

I. � Description of Event On February 1, 2001, with the plant operating at 100% power (operational mode 1), two non-safety related chart recorders were discovered by plant personnel installed and connected across the coils of solenoid valves which provide the safety-related functions for opening and closing the "D" main steam [SBI line atmospheric steam dump valve (1MS- PV3004). One chart recorder was found on the floor behind the "B" remote safe shutdown cabinet. The second chart recorder was found installed inside the Main Control Board. These recorders were installed to troubleshoot the operation of the subject solenoid valves. The subject recorders were not qualified for use in safety-related applications and no qualified isolation devices were used to provide the necessary separation from the safety-related equipment. If the recorders or associated leads shorted or grounded due to a failure or seismic event, it may have caused the subject solenoids to short or would have tripped the supply breaker causing the solenoid vales to go to their fail-safe position rendering 1MS-PV3004 inoperable. The subject recorders were subsequently removed.

These recorders were installed on November 28, 2000, during refueling outage 07 when the valves were not required to be operable. Technical Specification (TS) 3.7.1.6 specifies that four atmospheric relief valves and associated manual controls including the safety-related gas supply systems shall be operable during operational modes 1, 2, 3 and 4. Entry into mode 3 and 4 is permitted for up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to perform post-modification or post-maintenance testing to verify operability of components. Additionally, since 1MS-PV3004 is a containment isolation valve, the requirements of TS 3.6.3 apply, which requires the subject valve to be operable during operational modes 1, 2, 3, and 4. Seabrook Station entered Mode 4 on January 24, 2001. TS 3.0.4 requires that entry into an operational mode or another specified condition shall not be made when the conditions for the limiting conditions for operation are not met and the associated action requires a shutdown if they are not met within a specified time interval. Since the requirements of TS 3.0.4, 3.6.3 and 3.7.1.6 were not met, this is a condition prohibited by the Technical Specifications and is reportable pursuant to 10 CFR 50.73(a)(2)(i)(B).

II. Cause of Event

The cause of this event is human error.

III. Analysis of Event

There were no adverse consequences as a result of this event. This event is significant because either a failure of the recorders or a seismic event may have adversely affected the ability of 1MS-PV3004 to operate if required. During the period that the subject recorders were installed, 1MS-PV3004 was capable of operation. The subject valve was successfully full-stroke exercised on December 1, 2000 after the recorders were installed. The potential that the recorders could physically interact with other safety-related equipment was also reviewed. It was determined that no adverse consequences would have resulted with respect to the seismic interaction between the recorder and nearby safety-related structures, systems, or components.

The subject valve is one of four power operated relief valves located in the 30-inch main steam line from each steam generator. The subject valves provide for controlled removal of reactor decay heat during reactor cooldown, plant startup, and after a turbine trip, when the condenser and/or the turbine bypass system are not available. When available, the atmospheric relief valves can be used to reduce main steam pressure for both hot and cold shutdown conditions. Operation of the subject valves can be either automatic pressure control or manual position from the main control board. The subject valves can also be operated from the remote safe shutdown panel and locally.

IV. Corrective Actions

1. � The subject recorders were removed.

2. A review was performed to determine if the recorders could physically interact with other safety-related equipment in the event of a seismic event. This review concluded that no adverse consequences would have resulted between the recorder and nearby safety-related structures, systems, or components.

3. The individuals involved with this event were coached and counseled on their responsibilities associated with work package ownership.

4. Maintenance Department personnel were briefed on this event and the lessons learned were reinforced.

V. Additional Information

None.

Similar Events This is the first event of this type reported by Seabrook Station.

Manufacturer Data None.