Rockfall represents one of the most dangerous landslide phenomena, with serious impacts on infrastructure and work areas. In open pit mining, the occurrence is increased by unforeseen adverse structural conditions during min-ing operations or poor blasting practices. At the design stage, the geometric out-lines of the benches are generally chosen to minimize the impact of rockfalls. In standard practice, trajectory analyses are conducted using the ideal initial geom-etry to assess potential hazards in advance and determine effective mitigation measures. During mining activities, variations from the design profile, such as crest loss, flattening of the edge, and accumulation of debris at the toe of a bench, are frequently observed. In these cases, the catch capacity of the benches is re-duced, leading to potential increase of block run-out distances and impact ener-gies. In this study, we numerically investigate the impact of uncertainties related to slope topography, using more realistic slope profiles. The results are compared with those obtained for the ideal design geometry, providing powerful insights for preliminary rockfall hazard assessment and open pit slope design. A compar-ison with a real case is presented.