Restart criteria system

Closure of all ROMP RUIs ensures that adequate compensatory measures will be in place with regard to the 13 Designated Safety Systems listed in Attachment 1 of this SER section. The staff determined that the schedule submitted is acceptable and that Restart Criterion 4 has been satisfied. 

As a part of the Unreviewed Safety Question (USQ) review, the proposed activity must be evaluated to the criteria set forth in the Technical Specifications and the Safety Analysis Report (SAR). Seismic concerns and designs are both covered by the Technical Specifications and the SAR and are addressed by the USQ process. The procedure further requires that the USQ evaluation be approved by DOE prior to implementation of the activity when a USQ is determined to exist. The requirement to use the USQ process applies to all systems thereby enveloping the requirements of restart criterion 3. 

Restart Criterion 2 - Engineered Safety Feature (ESF) Systems... 

This restart criterion requires that WSRC demonstrate that ESF systems have a low probability of abnormal leakage, rapidly propagating failure, and gross rupture. The fluid and material compatibility for the ESF systems, and for the auxiliary systems that directly support the ESF systems, should be considered to reduce or eliminate the propensity of contaminant-induced piping... 

Methods shall be implemented to ensure that control room personnel can quickly contact on-shift operators or supervisors. The alternate methods cited in Restart Criterion 1, "Emergency Communications Systems," for communicating in high noise areas may be effective in accomplishing this function. However, to avoid operator confusion, distinction shall be made between a routine and an emergency notification. 

Restart Criterion 1 requires inspection and test programs to be defined and in place before reactor startup to ensure the integrity and operability of piping systems and equipment. 

We note that with regards to divergence, for example, the systematic aligiunent to a safe state in case of detected failure is generally irrelevant for HIPS whose inadvertent failures can cause other safety issues (risk at restart, water hammer, demands on other safety systems, human error, etc.) excluding production losses, which can be considerable. It follows that beyond the SIL, the probabihfy of a spurious failure is also an important design criterion. 

Restart evaluations against the RIMP criteria consider the ability of human performance (staffing and training) and management systems (procedures, instructions, checklists, and administrative programs) to support the conclusions reached. If any one of the RIMP criterion is met, the issue is considered to entail a critical deficiency that must be addressed prior to restart. The Issue Management Committee, may defer corrective actions to the post-restart period based on their considerations, including quantitative risk assessment results. 

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