As a solution to the identified problem, the evaluation of alternatives aimed at optimizing the advance per shot and improving the overall efficiency of the development cycle was proposed. Two key opportunities for improvement were identified: • Increase the drilling length from 24 to 28 feet, to reduce the number of cycles required and increase operational performance. • Implement a smart hybrid initiation, combining electronic detonators in the cut zone and nonelectric (pyrotechnic) detonators in the remaining holes, seeking to take advantage of the precision and flexibility of electronic detonators together with the operational simplicity and lower cost of pyrotechnic systems. The objective of this strategy is to increase the feed per cycle, while keeping the costs associated with the drilling and blasting (P&V) process under control. As part of the implementation plan, the drill and blast mesh was redesigned, adapting it to 28-foot fronts. This new configuration was validated in the cabinet and later tested in the field, through a series of controlled blasts. Additionally, operational controls were incorporated during the loading process, complemented by instrumentation for monitoring and verification of performance in the field. For the technical evaluation, four cut tests were carried out, aimed at determining: • The optimal cutting scheme (type of cut). • The most suitable delay times for the firing sequence with electronic detonators. These tests allowed validating the behavior of the new strategy under real operating conditions, establishing a technical basis for its continuous application in development tasks with long drilling. Cut Tests i. Initial Cut Design From the design point of view, the most relevant considerations focused on achieving an effective feed of close to 8.0 m, using 54 mm diameter break holes and determining the optimal number of relief holes, which have a diameter of 102 mm. Since the drilling length is 8.0 m, the equivalent relief diameter was calculated using the mathematical model proposed by Holmberg (1982), according to equation (1): where: Ø equivalent = 110 + 15.4 x L (1)
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