2016:23 Technical Note, Modelling of the thermal evolution of the KBS-3 repository at Forsmark and associated induced seismic activity

Main Review Phase

Introduction

The Swedish Radiation Safety Authority (SSM) reviews the Swedish Nuclear Fuel Company’s (SKB) applications under the Act on Nuclear Activities (SFS 1984:3) for the construction and operation of the KBS-3 repository for spent nuclear fuel and for an encapsulation facility. As part of the review, SSM commissions consultants to carry out work in order to obtain information and provide expert opinions on specific scientific and technical issues. The results from the consultants’ tasks are reported in SSM’s Technical Note series. The general objective of the review is to provide comments on SKB’s post-closure safety analysis, SR-Site (SKB, 2011), for the proposed repository at Forsmark, Sweden. In particular, this assignment concerns the development of the shear displacement along repository fractures induced by the heat that is generated by the disposed canisters containing the spent nuclear fuel. This assignment also concerns the shear displacement of the repository fractures induced by an earthquake at a nearby deformation zone occurring while the repository is under heat loading from the disposed canisters. This Technical Note is complementary to SSM Technical Note 2014:59 entitled “Relation between earthquake magnitude, fracture length and fracture shear displacement in the KBS-3 repository at Forsmark – Main Review Phase” (Yoon et al., 2014).