SLOPE STABILITY BY CLASSIFICATION SSPC RMR GSI ROBERT HACK ENGINEERING GEOLOGY, ESA, ITC, FACULTY OF GEO-INFORMATION SCIENCE AND EARTH OBSERVATION, UNIVERSITY OF TWENTE, THE NETHERLANDS. PHONE:+31 (0)6 24505442; EMAIL: HACK@ITC.NL TU Delft, The Netherlands, 12 September 2016