An Evaluation of Drilling and Blasting Techniques at the Granite Quarry of Sunshine Plc Farakwai Igabi Lga Kaduna State

ABSTRACT This study evaluates the drilling and blasting techniques employed at the Sunshine Farakwai Granite Quarry in Kaduna, Nigeria, with the aim of identifying operational inefficiencies and proposing strategies for improvement. A mixed-methods research design was adopted, combining both qualitative and quantitative approaches. Data were collected through semi-structured interviews, direct site observations, and a review of operational records. Key drilling parameters such as the use of wagon drills, a drill hole diameter of 89 mm, a depth of 10 meters, and a burden and spacing of 2meter were examined. Blasting operations primarily utilized ANFO explosives in a square blast pattern with a 12-millisecond delay interval, resulting in a powder factor of 2.277 kg/m³. The findings revealed significant challenges, including inadequate drilling accuracy monitoring, suboptimal burden and spacing, frequent occurrences of fly rock, and excessive air overpressure. Additionally, environmental and safety practices were found to be insufficient, with limited dust suppression measures and no formal vibration monitoring system in place. These inefficiencies have led to poor rock fragmentation, increased processing costs, and heightened safety risks.To address these issues, the study recommends optimizing drilling parameters by increasing burden and spacing to 2.50–3.00 meters, adopting advanced drilling technologies such as Down-the-Hole (DTH) drills, improving stemming techniques, and increasing the powder factor to 2.50–3.00 kg/m³. The adoption of electronic detonators for precise initiation timing, the installation of vibration monitoring systems, and the enhancement of environmental and safety measures are also recommended.Implementing these strategies is expected to improve rock fragmentation, enhance operational efficiency, reduce safety risks, and lower overall production costs. This study provides valuable insights for quarry operators seeking to optimize drilling and blasting operations and promote sustainable quarrying practices