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At 1345 (CDT), on 09-04-04 the Plant Shift … At 1345 (CDT), on 09-04-04 the Plant Shift Superintendent was notified of a violation of Nuclear Criticality Safety (NCS) control in the C-337 process building. During Inspection of the RCW (Recirculating Cooling Water) line to the RCW/ R114 Differential Pressure alarm switches (DP switches) for the C-337 #5 Low Speed P&E (Purge and Evacuation) Pump, Instrument Maintenance discovered that the instrument line boss was plugged. This condition rendered both Independent DP switches incapable of performing their intended safety, violating an SRI (Safety Related Item) in Nuclear Criticality Safety Evaluation (NCSE) 039. The SRI requires that both DP alarms are to be functional while the P&E pump is Isolated from the cascade process system. The purpose of the SRI is to alert an operator to take actions within a 28 hour timeframe to prevent high moisture R-114 from leaking into the process gas system. The DP alarms had likely been nonfunctional for more than 28 hours when discovered. Clarity of the Instrument line boss was subsequently re-established and both DP alarms were returned to service. The R-114 was sampled and determined to be dry (low moisture content) within 4 hours of discovery, thereby re-establishing double contingency.</br>SAFETY SIGNIFICANCE OF EVENTS:</br>While the R-114 was demonstrated to be dry, both OF alarms relied on for double contingency were disabled without the knowledge of the operators. </br>CONTROLLED PARAMETERS:</br>Double contingency Is maintained by Implementing two controls on moderation.</br>NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION OF THE FAILURES OR DEFICIENCIES:</br>The first leg of double contingency is based on the DP switch alarming to alert the operator to take action to either verify the R-114 is dry or to isolate the RCW and remove the R-114 from the system in order to prevent water from leaking into the process gas system. This DP alarm was not maintained as functional. The DP alarm was put back In service and the R-114 was sampled and found to be dry. The SRI was not maintained and the control was violated but the process condition was maintained.</br>The second leg of double contingency is based on the independent DP switch alarming to alert the operator to take action to either verify the R-114 is dry or to Isolate the RCW and remove the R-114 from the system in order to prevent water from leaking into the process gas system. The independent DP alarm was not maintained as functional. The independent DP alarm was put back in service and the R-114 was sampled and found to be dry. The SRI was not maintained and the control was violated but the process condition was maintained. This re-established double contingency. </br>CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEMS AND WHEN EACH WAS IMPLEMENTED:</br>Both DP switches were returned to service and the R-114 was sampled and found to be dry within four hours time of discovery.</br>PGDP Problem Report No. ATR-04-3602; PGDP Event Report No. PAD-2004-22</br>The Senior NRC Resident Inspector has been notified of this event.esident Inspector has been notified of this event.
18:45:00, 4 September 2004 +
41,020 +
21:29:00, 4 September 2004 +
18:45:00, 4 September 2004 +
At 1345 (CDT), on 09-04-04 the Plant Shift … At 1345 (CDT), on 09-04-04 the Plant Shift Superintendent was notified of a violation of Nuclear Criticality Safety (NCS) control in the C-337 process building. During Inspection of the RCW (Recirculating Cooling Water) line to the RCW/ R114 Differential Pressure alarm switches (DP switches) for the C-337 #5 Low Speed P&E (Purge and Evacuation) Pump, Instrument Maintenance discovered that the instrument line boss was plugged. This condition rendered both Independent DP switches incapable of performing their intended safety, violating an SRI (Safety Related Item) in Nuclear Criticality Safety Evaluation (NCSE) 039. The SRI requires that both DP alarms are to be functional while the P&E pump is Isolated from the cascade process system. The purpose of the SRI is to alert an operator to take actions within a 28 hour timeframe to prevent high moisture R-114 from leaking into the process gas system. The DP alarms had likely been nonfunctional for more than 28 hours when discovered. Clarity of the Instrument line boss was subsequently re-established and both DP alarms were returned to service. The R-114 was sampled and determined to be dry (low moisture content) within 4 hours of discovery, thereby re-establishing double contingency.</br>SAFETY SIGNIFICANCE OF EVENTS:</br>While the R-114 was demonstrated to be dry, both OF alarms relied on for double contingency were disabled without the knowledge of the operators. </br>CONTROLLED PARAMETERS:</br>Double contingency Is maintained by Implementing two controls on moderation.</br>NUCLEAR CRITICALITY SAFETY CONTROL(S) OR CONTROL SYSTEM(S) AND DESCRIPTION OF THE FAILURES OR DEFICIENCIES:</br>The first leg of double contingency is based on the DP switch alarming to alert the operator to take action to either verify the R-114 is dry or to isolate the RCW and remove the R-114 from the system in order to prevent water from leaking into the process gas system. This DP alarm was not maintained as functional. The DP alarm was put back In service and the R-114 was sampled and found to be dry. The SRI was not maintained and the control was violated but the process condition was maintained.</br>The second leg of double contingency is based on the independent DP switch alarming to alert the operator to take action to either verify the R-114 is dry or to Isolate the RCW and remove the R-114 from the system in order to prevent water from leaking into the process gas system. The independent DP alarm was not maintained as functional. The independent DP alarm was put back in service and the R-114 was sampled and found to be dry. The SRI was not maintained and the control was violated but the process condition was maintained. This re-established double contingency. </br>CORRECTIVE ACTIONS TO RESTORE SAFETY SYSTEMS AND WHEN EACH WAS IMPLEMENTED:</br>Both DP switches were returned to service and the R-114 was sampled and found to be dry within four hours time of discovery.</br>PGDP Problem Report No. ATR-04-3602; PGDP Event Report No. PAD-2004-22</br>The Senior NRC Resident Inspector has been notified of this event.esident Inspector has been notified of this event.
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00:00:00, 4 September 2004 +
GDP-1 +
Modification date"Modification date" is a predefined property that corresponds to the date of the last modification of a subject and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.
23:40:26, 24 November 2018 +
21:29:00, 4 September 2004 +
0.114 d (2.73 hours, 0.0162 weeks, 0.00374 months) +
18:45:00, 4 September 2004 +
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