RSC-Programme - Interim Report. Approach and Basis for - Posiva

1TABLE OF CONTENTSABSTRACTTIIVISTELMÄPREFACE1 INTRODUCTION .................................................................................................... 32 BACKGROUND ..................................................................................................... 72.1 Regulatory requirements ............................................................................. 72.2 Host rock classification (HRC) and its testing in ONKALO .......................... 92.2.1 General .......................................................................................... 92.2.2 Methodology and data .................................................................... 92.2.3 Results ......................................................................................... 132.2.4 Development needs ..................................................................... 152.3 SKB approach .......................................................................................... 162.4 KBS-3H work ............................................................................................ 173 GENERAL APPROACH AND METHODOLOGY .................................................. 194 LONG-TERM SAFETY RELATED REQUIREMENTS ON HOST ROCK .............. 254.1 Safety concept and safety functions.......................................................... 254.2 Repository depth....................................................................................... 274.3 Performance targets related to functionality of the engineered barriers ..... 284.3.1 Canister ........................................................................................ 284.3.2 Buffer ........................................................................................... 304.3.3 Backfill .......................................................................................... 324.3.4 Summary ...................................................................................... 344.4 Performance targets related to radionuclide transport ............................... 354.5 Other issues need to be considered.......................................................... 364.5.1 Disturbances caused by excavation and operation ....................... 364.5.2 Mutual compatibility of and interfaces between the barriers .......... 374.5.3 Groundwater flow regime ............................................................. 374.6 Summary of the host rock performance targets ........................................ 375 DEVELOPMENT OF THE ROCK SUITABILITY CRITERIA ................................. 415.1 Approach to the criteria development ........................................................ 415.2 Layout-determining features and respect distance volumes ...................... 415.2.1 Introduction .................................................................................. 415.2.2 Methodology ................................................................................. 435.2.3 Data and models .......................................................................... 545.2.4 Results ......................................................................................... 575.2.5 Uncertainties in layout determining features and respectdistance volumes ......................................................................... 735.3 Rock suitability criteria, RSC-I................................................................... 745.3.1 Site characteristics of relevance to the performance targets ......... 745.3.2 Evolution of the Olkiluoto site and its impact on the criteria .......... 825.3.3 Criteria related to the hydrogeological properties of the rock ........ 845.3.4 Criteria related to the mechanical properties of the rock ............... 865.3.5 Aspects related to the application of the RSC in practice .............. 875.3.6 Discussion and development needs ............................................. 97