Mnichova Lehota is a limestone & dolomite quarry with annual production around 350,000 tons which is consumed mainly by the construction industry. The typical blast parameters are 89 mm hole diameter, 19.5 m hole length with 1 m subdrill and pattern 3 m x 3.2 m. The usual blast size is around 15,000 – 17,000 tons of rock blasted by 1.9 tons of explosives in approximately 30 holes. Austin Powder Slovakia provides full rock-on-the-ground service for this quarry.

Geology variation throughout the quarry made it difficult to keep consistent fragmentation. Most of the time the muckpile contained boulders that required intense secondary breaking by a hydraulic hammer. Subsequently, the blasts were creating uneven faces that were influencing safety on bench; making it harder for blast planning to keep the patterns uniform as needed for the desired final fragmentation.

Thorough analysis of the geological conditions as well as the blasts fragmentation together with Paradigm geological modeling provided calculations of the optimum timing for the best fragmentation results.

Specific timing suitable only for the implementation by the use of the E*STAR detonators was gradually improved using drone photogrammetry, fragmentation evaluation and tweaking the geological model.

The precise electronic timing brought straightening of the faces after the blast.