REVIEW OF THE PAPER BY MULARGIA ET AL., 2017, “WHY IS PROBABILISTIC SEISMIC HAZARD ANALYSIS (PSHA) STILL USED?”; And Implications for the Proposed Olkiluoto High-Level Nuclear Waste Repository, Finland

The above paper recommends abandoning the PSHA methodology, which has been and is being used at the Finnish nuclear waste disposal site. We advised the Finnish nuclear regulator (STUK) that most of the post-2000 “failures” of PSHA can be attributed to bad data input in the SSC phase of the PSHA, and not to flaws in the PSHA method itself. Some recent “failures” of PSHA are due to its time-independent assumption for large earthquakes, but “work-arounds” do exist for making time-dependent PSHAs. None of the failures have arisen from fundamental laws in the Ground Motion Prediction phase of PSHA or from the mathematical algorithms of either the SSC or GMPE phases.