ML16015A062

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Briefing Notes for 95003 Inspection at Arkansas Nuclear One
ML16015A062
Person / Time
Site: Arkansas Nuclear  Entergy icon.png
Issue date: 01/20/2016
From:
NRC/RGN-IV/DRP
To:
O'Keefe N
References
Download: ML16015A062 (3)


Text

Briefing Notes for 95003 Inspection at Arkansas Nuclear One 2:00 pm EST/1:00 pm CST January 20, 2015 Nuclear Regulatory Commission (NRC) Staff

Participants:

  • Neil OKeefe, Branch Chief and 95003 Inspection Team Leader
  • Brian Tindell, Senior Resident Inspector Purpose To provide a current status of performance regulatory oversight and performance improvement efforts to improve safety performance at the Arkansas Nuclear One nuclear power plant.

Background

The NRC increased regulatory oversight of Entergys Arkansas Nuclear One (ANO) plant in the third quarter of 2014. ANO was placed into Column 4, Multiple/Repetitive Degraded Cornerstone, of the NRCs Action Matrix as a result of having two Yellow findings affecting each of the two plants. The NRCs color coding indicates that Yellow findings have substantial safety significance. These findings were identified as a result of the events surrounding the industrial accident that occurred at the plant on March 31, 2013, which resulted in one fatality and eight injured personnel. One Yellow finding involved performance deficiencies identified from the event associated with dropping a heavy component and causing significant damage to plant equipment. The other Yellow finding involved performance deficiencies associated with inadequate flood protection of safety equipment that was exposed as a result of plant damage from the heavy component drop.

Event Description On March 31, 2013, during a planned Unit 1 outage, the licensee was lifting the Unit 1 main generator stator out of the turbine building when an inadequately designed temporary lifting rig failed, causing the 525 ton stator to fall approximately 30 feet into the train bay. The train bay is shared between Unit 1 and Unit 2. The impact caused substantial damage to the Unit 1 side of the turbine building and power distribution systems, and parts of the lift rig impacted the Unit 2 side of the turbine building.

Yellow Finding Associated with the Heavy Component Drop The temporary lifting rig collapsed because there were incorrect assumptions and errors in the design such that it could not safely complete the intended lift. A test to verify the capability of the lift rig was not performed due to further errors in communication and decision making. These failures were the result of inadequate oversight of the primary contractor and a subcontractor hired to perform the operation.

As a result, there was a complete loss of offsite power to Unit 1 for six days, and Unit 2 partially lost offsite power. This increased risk to the plant because alternate means of providing electrical

power to key safety-related systems was not available using installed plant equipment in the event the diesels failed. The NRC determined that this constituted a violation of substantial safety significance.

Yellow Finding for Degraded Flood Protection Features Following the flooding that occurred during the heavy component drop event, the licensee conducted a comprehensive inspection and identified over 100 deficient flood protection features, including unsealed electrical cable conduits, and degraded hatches and floor plug seals in the auxiliary and emergency diesel fuel storage buildings. NRC inspections subsequently identified additional problems, necessitating further reviews. Both Unit 1 and Unit 2 Safety Analysis Reports (SARs) require that the auxiliary building and safety-related pump rooms be watertight.

The NRC concluded that the licensee had failed to design, construct, and maintain the flood protection features in both units in accordance with the approved design requirements. The finding included multiple violation examples and was determined to have substantial safety significance. The primary contributor to the safety significance was due to the potential safety impact of the theoretical maximum rainfall event, which could lead to core damage due to equipment damage from the degraded flood protection features.

NRC Actions

  • The safe operation of the units is the NRCs primary concern. We have three inspectors onsite that are continuously assessing day to day operation, and we are documenting our assessment that continued plant operation is acceptable in quarterly inspection reports.
  • ANO is currently receiving one of the highest levels of NRC oversight designed to ensure that the plant continues to operate safely and performance does not further decline. If safety performance declines further, the NRC will promptly identify and address the decline with regulatory actions up to and including shutting the units down.
  • Both the NRC and the licensee are in the process of evaluating the nature and extent of performance issues. We have reviewed the results of each of their evaluations and interim actions to avoid further performance decline.
  • The NRC will begin a comprehensive inspection on January 25, 2016. The inspection will involve a team of about 25 inspectors who will spend about 3,600 hours0.00694 days <br />0.167 hours <br />9.920635e-4 weeks <br />2.283e-4 months <br /> on the effort.

This inspection will be an independent evaluation of the extent of the performance problems at Arkansas Nuclear One. We will also assess the licensees evaluation of their problems and their proposed corrective actions to ensure they lead to timely and sustained performance improvements.

  • We expect to issue an inspection report with the findings and assessments of the team in the spring of 2016. We have tentatively scheduled a public exit meeting for April 6, 2016, and will also present the results of the NRCs annual assessment.

Victor McCree, the NRCs Executive Director for Operations, is expected to attend this meeting.

ML16015A062 SUNSI Review ADAMS Publicly Available Non-Sensitive Keyword:

By: JLD Yes No Non-Publicly Available Sensitive NRC-002 OFFICE DRP/PBE NAME J.Dixon SIGNATURE /RA/

DATE 01-15-16 Briefing Notes for 95003 Inspection at Arkansas Nuclear One 2:00 pm EST/1:00 pm CST January 20, 2015 Nuclear Regulatory Commission (NRC) Staff

Participants:

  • Neil OKeefe, Branch Chief and 95003 Inspection Team Leader
  • Brian Tindell, Senior Resident Inspector Purpose To provide a current status of performance regulatory oversight and performance improvement efforts to improve safety performance at the Arkansas Nuclear One nuclear power plant.

Background

The NRC increased regulatory oversight of Entergys Arkansas Nuclear One (ANO) plant in the third quarter of 2014. ANO was placed into Column 4, Multiple/Repetitive Degraded Cornerstone, of the NRCs Action Matrix as a result of having two Yellow findings affecting each of the two plants. The NRCs color coding indicates that Yellow findings have substantial safety significance. These findings were identified as a result of the events surrounding the industrial accident that occurred at the plant on March 31, 2013, which resulted in one fatality and eight injured personnel. One Yellow finding involved performance deficiencies identified from the event associated with dropping a heavy component and causing significant damage to plant equipment. The other Yellow finding involved performance deficiencies associated with inadequate flood protection of safety equipment that was exposed as a result of plant damage from the heavy component drop.

Event Description On March 31, 2013, during a planned Unit 1 outage, the licensee was lifting the Unit 1 main generator stator out of the turbine building when an inadequately designed temporary lifting rig failed, causing the 525 ton stator to fall approximately 30 feet into the train bay. The train bay is shared between Unit 1 and Unit 2. The impact caused substantial damage to the Unit 1 side of the turbine building and power distribution systems, and parts of the lift rig impacted the Unit 2 side of the turbine building.

Yellow Finding Associated with the Heavy Component Drop The temporary lifting rig collapsed because there were incorrect assumptions and errors in the design such that it could not safely complete the intended lift. A test to verify the capability of the lift rig was not performed due to further errors in communication and decision making. These failures were the result of inadequate oversight of the primary contractor and a subcontractor hired to perform the operation.

As a result, there was a complete loss of offsite power to Unit 1 for six days, and Unit 2 partially lost offsite power. This increased risk to the plant because alternate means of providing electrical

power to key safety-related systems was not available using installed plant equipment in the event the diesels failed. The NRC determined that this constituted a violation of substantial safety significance.

Yellow Finding for Degraded Flood Protection Features Following the flooding that occurred during the heavy component drop event, the licensee conducted a comprehensive inspection and identified over 100 deficient flood protection features, including unsealed electrical cable conduits, and degraded hatches and floor plug seals in the auxiliary and emergency diesel fuel storage buildings. NRC inspections subsequently identified additional problems, necessitating further reviews. Both Unit 1 and Unit 2 Safety Analysis Reports (SARs) require that the auxiliary building and safety-related pump rooms be watertight.

The NRC concluded that the licensee had failed to design, construct, and maintain the flood protection features in both units in accordance with the approved design requirements. The finding included multiple violation examples and was determined to have substantial safety significance. The primary contributor to the safety significance was due to the potential safety impact of the theoretical maximum rainfall event, which could lead to core damage due to equipment damage from the degraded flood protection features.

NRC Actions

  • The safe operation of the units is the NRCs primary concern. We have three inspectors onsite that are continuously assessing day to day operation, and we are documenting our assessment that continued plant operation is acceptable in quarterly inspection reports.
  • ANO is currently receiving one of the highest levels of NRC oversight designed to ensure that the plant continues to operate safely and performance does not further decline. If safety performance declines further, the NRC will promptly identify and address the decline with regulatory actions up to and including shutting the units down.
  • Both the NRC and the licensee are in the process of evaluating the nature and extent of performance issues. We have reviewed the results of each of their evaluations and interim actions to avoid further performance decline.
  • The NRC will begin a comprehensive inspection on January 25, 2016. The inspection will involve a team of about 25 inspectors who will spend about 3,600 hours0.00694 days <br />0.167 hours <br />9.920635e-4 weeks <br />2.283e-4 months <br /> on the effort.

This inspection will be an independent evaluation of the extent of the performance problems at Arkansas Nuclear One. We will also assess the licensees evaluation of their problems and their proposed corrective actions to ensure they lead to timely and sustained performance improvements.

  • We expect to issue an inspection report with the findings and assessments of the team in the spring of 2016. We have tentatively scheduled a public exit meeting for April 6, 2016, and will also present the results of the NRCs annual assessment.

Victor McCree, the NRCs Executive Director for Operations, is expected to attend this meeting.

ML16015A062 SUNSI Review ADAMS Publicly Available Non-Sensitive Keyword:

By: JLD Yes No Non-Publicly Available Sensitive NRC-002 OFFICE DRP/PBE NAME J.Dixon SIGNATURE /RA/

DATE 01-15-16