Peer Review (Task 16)

Task Overview

Objective

The objective of the peer review is to have the SPRA study endorsed by independent risk analysts.

Purpose

The purpose of the SPRA peer review is to assess the SPRA and determine whether the methodology and its implementation meet the requirements of Part 5 of ASME/ANS Standard. Another purpose of the peer review is to determine strengths and weaknesses in the SPRA.

Guidance

The AMSE/ANS Standard provides requirements for performing a review that include:

• The composition of the peer review team and the qualifications of team members.
• The scope of the peer review including:

- Whether the seismic hazard study used in the PRA is appropriately specific to the site and has met the relevant requirements of the Standard.

- Whether the seismically induced initiating events are properly identified, the SSCs are properly modeled, and the accident sequences are properly quantified as well as that the SEL is reasonable for the plant, considering the reactor type, plant vintage, and specific design.

- Whether the seismic response analysis used in the development of seismic fragilities meets the relevant requirements of the Standard including the input ground motion, structural modeling including SSI effects, parameters of structural response, and the reasonableness of the calculated seismic response.

- Whether the seismic walkdown provides valid screening, seismic spatial interactions, and identification of critical failure modes.

- Whether the methods and data used in the fragility analysis of SSCs are adequate for the purpose. The review team should perform independent fragility calculations of a selected sample of components covering different categories and contributions to CDF and LERF.

- Whether the seismic quantification method used in the seismic PRA is appropriate and provides all the results and insights needed for risk-informed decisions, including the CDF and LERF estimates, and uncertainty bounds and on the significant risk contributors.

Supplemental Guidance

Related Element of ASME/PRA Standard

Part 5, Seismic Hazard Analysis (SHA)

Part 5, Seismic Fragility Response (SFR)

Part 5, Seismic Plant-Response (SPR)

EPRI Guidance

(none noted)

Other Guidance

NRC Regulatory Guide 1.200, Revision 2

NEI 12-13, “External Hazards PRA Peer Review Process Guidelines,” provides industry-approved guidance for performing the SPRA peer review.

NEI 00-02, “Probabilistic Risk Assessment Peer Review Process Guidance”

NEI 05-04, “Process for Performing PRA Peer Reviews Using the ASME PRA Standard (Internal Events)”

NEI 07-12, “Fire Probabilistic Risk Assessment Peer Review Process Guidelines”

NEI 17-07, Revision 2, “Performance of PRA Peer Reviews Using the ASME/ANS PRA Standard”