05000254/FIN-2018001-04
From kanterella
Jump to navigation
Jump to search
Finding | |
|---|---|
| Title | Enforcement Action: EA18021: EDG Non-conformance for Tornado Missiles (EGM 15002) |
| Description | On June 10, 2015, the NRC issued Regulatory Issue Summary (RIS) 201506, Tornado Missile Protection (ML15020A419), focusing on the requirements regarding tornado-generated missile protection and required compliance with the facility-specific licensing basis. The RIS also provided examples of noncompliance that had been identified through different mechanisms and referenced Enforcement Guidance Memorandum (EGM) 15002, Enforcement Discretion For Tornado Generated Missile Protection Non-Compliance, which was also issued on June 10, 2015, (ML15111A269) and revised on February 7, 2017 (ML16355A286). The EGM applies specifically to a structure, system, and component (SSC) that is determined to be inoperable for tornado-generated missile protection. The EGM stated that a bounding risk analysis performed for this issue concluded that tornado missile scenarios do not represent an immediate safety concern because their risk is within the LIC504, Integrated Risk-Informed Decision-Making Process for Emergent Issues, risk acceptance guidelines. In the case of Quad Cities Nuclear Generating Station, the EGM provided for enforcement discretion of up to 3 years from the original date of issuance of the EGM. The EGM allowed NRC staff to exercise this enforcement discretion only when a licensee implements, prior to the expiration of the time mandated by the limiting conditions for operation (LCO), initial compensatory measures that provided additional protection such that the likelihood of tornado missile effects were lessened. In addition, licensees were expected to follow these initial compensatory measures with more comprehensive compensatory measures within approximately 60 days of issue discovery. The comprehensive measures should remain in place until permanent repairs are completed or until the NRC dispositions the non-compliance in accordance with a method acceptable to the NRC such that discretion is no longer needed. In 1967, the NRC issued general design criterion to which the Quad Cities Nuclear Generating Station was evaluated against. Quad Cities Updated Final Safety Analysis Report (UFSAR), Section 3.1, Conformance with NRC General Design Criteria, discusses this criterion and its applicability to the sites design. Specifically, UFSAR Section 3.1.1.2, Criterion 2Performance Standards, states, those systems and components essential to the prevention of accidents or to mitigation of their consequences shall be designed, fabricated, and erected to performance standards that will enable the facility to withstand, without loss of the capability to protect the public, the additional forces that might be imposed by natural phenomena such as earthquakes, tornadoes, flooding conditions, winds, ice, and other local site effects. Section 3.1.1.2 further states that plant equipment which is important to safety is designed to permit safe plant operation and to accommodate all design basis accidents for all appropriate environmental phenomena at the site without loss of their capability. On March 1, 2018, during an engineering review of the Quad Cities, Units 1 and 2 facility design, the licensee identified a nonconforming condition with the aforementioned general design criterion. Specifically, the licensee identified that the three EDG systems intake stacks, exhaust stacks, fuel oil storage tank vent lines, and diesel oil day tank vent lines were inadequately protected against tornado missiles. As a result of the nonconforming condition, the licensee declared the Units 1, 2, and 12 EDG systems inoperable and entered the Technical Specifications (TS) LCO required action statements. The condition was reported to the NRC in Event Notice 53235 as an unanalyzed condition and a condition that could have prevented fulfillment of a safety function. Corrective Actions: The licensee documented the inoperability and functionality of the affected SSCs and the applicable TS LCO action statements in the CAP and in the control room operating log. The shift manager notified the NRC resident inspector of implementation of EGM 15002 and documented the implementation of the compensatory measures to establish the SSCs as operable but nonconforming prior to expiration of the required LCO action statements. The licensees initial (and final) compensatory measures included: verification that procedures and training for a tornado watch or warning were in place to provide additional instructions for operators to respond in the event of tornados or high winds, and a potential loss of SSCs vulnerable to the tornado missiles; confirmation of readiness of equipment and procedures dedicated to the Diverse and Flexible Coping Strategy (FLEX); verification that training was up to date for individuals responsible for implementing preparation and emergency response procedures; establishment of a heightened level of station awareness and preparedness relative to identifying tornado missile vulnerabilities; and revision to procedure QCOA 001010, Tornado Watch-Warning, Severe Thunderstorm Warning, or Severe Winds, to include guidance for unobstructing and/or repairing crimped diesel fuel oil tank vent lines. Corrective Action References: IR 1281009: Tornado Missile Protection Unresolved Item and IR 4110003: EDG Non-Conformance for Tornado Missiles Enforcement: Violation: The enforcement discretion was applied to the required shutdown actions of the following TS LCOs for both units: TS 3.0.3: General Shutdown LCO (cascading or by reference from other LCOs); and TS 3.8.1: AC SourcesOperating. Severity/Significance: The subject of this enforcement discretion, associated with tornado missile protection deficiencies, was determined to be less than red (i.e., high safety significance) based on a generic and bounding risk evaluation performed by the NRC in support of the resolution of tornado-generated missile non-compliances. The bounding risk evaluation is discussed in Enforcement Guidance Memorandum 15002, Revision 1, Enforcement Discretion for Tornado-Generated Missile Protection Non-Compliance, and can be found in ADAMS Accession No. ML16355A286. Basis for Discretion: The NRC exercised enforcement discretion in accordance with Section 2.3.9 of the Enforcement Policy and EGM 15002 because the licensee initiated initial compensatory measures that provided additional protection such that the likelihood of tornado missile effects were lessened. The licensee reviewed their initial compensatory measures to determine if more comprehensive compensatory measures were warranted. Upon their review, the licensee concluded that their initial compensatory measures were sufficient to satisfy both the short-term and long-term actions required by the EGM and therefore no additional actions were necessary for enforcement discretion. The disposition of this enforcement discretion closes URI05000254/201100904; 05000265/ 201100904: Tornado Missile Protection of the Emergency Diesel Generator Air Intake and Exhaust. |
| Site: | Quad Cities  |
|---|---|
| Report | IR 05000254/2018001 Section 1R15 |
| Date counted | Mar 31, 2018 (2018Q1) |
| Type: | Violation: Severity level Enforcement Discretion |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71111.15 |
| Inspectors (proximate) | R Murray K Carrington S Bell B Bergeon M Domke M Holmberg J Neurauter C Mathews L Torres K Stoedter |
| Violation of: | Technical Specification |
| INPO aspect | |
| ' | |
Finding - Quad Cities - IR 05000254/2018001 | |||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Finding List (Quad Cities) @ 2018Q1
| |||||||||||||||||||||||||