The safety factors matched between the site specific and the regional scale analyses, while risk levels did not. The runout distance was relatively small, yielding a low risk failure. The studied slope failed under both seismic events with 10% exceedance probability in 50 years, and rainfall events with 10-year return period. At failure, the maximum runout distance and the corresponding angle of reach were determined in Rocscience RocFall 8.0. A limestone quarry in Bafliye, Southern Lebanon, was mapped with a DJI Phantom 4 V2.0 drone, recreated as a 3D scene in Pix4D Mapper, assessed kinematically in Rocscience DIPS 7.0, and analyzed using limit equilibrium and numerical modelling techniques using both Rocscience SWEDGE 7.0 and RS2 11.0. The aim is to also ascertain the degree of accuracy of the regional scale maps in predicting landslides in quarried areas. In this research, we present a methodology to assess, at a site specific level, the hazard and risk levels of quarried slopes under three conditions: dry, heavy rainfall, and seismic events. However, their applicability to quarried slopes was not tested. Regional scale maps were recently generated in a Geographic Information System (GIS) platform to identify hazard and risk levels of co-seismic and rainfall induced landslides. In Lebanon, quarries are scattered randomly across the country and lack proper urban planning and management. Quarrying activities in particular, contribute largely to slope failures worldwide, especially when unorganized and chaotic.
Rockfall trajectory modelling techniques allow the calculation of vertical distribution of rocks falling from the quarry’s walls along different profiles in the area and therefore the determination of a safety perimeter from the quarry wall.Human activities are continuously altering the steepness of natural slopes, making them vulnerable to slide under natural triggering factors like earthquakes and rainfall. Using rockmass characterization techniques, kinematic study and stability analysis, it was confirmed that many instability mechanisms are found on the walls of the quarry and cause a high risk of rockfall during the rain season, especially that the study area is inhabited. Quarries are places of high instability due to blastings, if left without rehabilitation they become sites of great risk of rockfall, which are the case of the Carian quarry, a small abandoned aggregate quarry, which turned into a slum neighborhood in the north western part of the city of Tétouan, and that has a long history of rockfall incidents since it was shut down in the 60’s. Rockfall Hazard in an Old Abandoned Aggregate Quarry in the City of Tétouan, MoroccoĪbandoned Quarry Rockfall Safety Parameter Tétouan RocScience: “User’s Guide of Code ROCFALL, ROCLAB, SWEDGE, ROCPLANE & DIPS,” RocScience Inc., Toronto, 2004.
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