Geotechnical Investigation at lignite minesGeotechnical Investigation at lignite mines Peer-Reviewed Journal Publication Δημοσίευση σε Περιοδικό με Κριτές 2015-10-201999enOpen pit lignite mining provides the energy resources for about 80% of the electrical energy annually consumed in Greece. Optimum open pit slope stability design is related to the minable reserves as well as the cost of mining. This paper presents a geotechnical investigation for the "Tomeas 6" lignite mine at the Ptolemais-Amydeon basin (in northern Greece), including sample testing, interpretation of inclinometer and geodetic data, and slope stability analysis performed in order to determine the potential of mine slope failure. This investigation was initiated after slope cracks and floor heaving were observed following mining operations. Results indicate that cracking on the slope as well as floor heaving may be attributed to stress relief due to mining. http://creativecommons.org/licenses/by/4.0/Mineral Resources Engineering48405-418 Steiakakis Manolis Στειακακης Μανωλης Agioutantis Zacharias Αγιουταντης Ζαχαριας Mines