Introducing high-accuracy tools to help a limestone mine’s drilling and blasting operation address a specialty blasting scenario for safety and efficiency
Client: Nordkalk Corporation and Finnsementti, CRH
Time Span: 2019
Related Service Areas
RESPEC’s international mining team worked with two of Northern Europe’s leading limestone and cement producing companies in Finland. The mining team performed a critical blasting study and evaluation at the Parainen quarry site to assess the client’s current drill and blast practices and improve them for a specialty blasting case. The team collected baseline data, trial-blasted a challenging mine bench with steep jointing that caused safety concerns and monitored the joint system to ensure it was not affected by the blast.
RESPEC’s two-week site visit focused on a difficult area of a highly jointed rock bench, which is targeted in a long-term mine plan as the final wall where significant limestone reserves could be accessed at depth. The problematic bench is not yet extracted and is hard to access, jointing is unfavorable and dips down out of the face, and critical infrastructure, including a fuel station and crusher, are located nearby.
RESPEC’s approach was to evaluate the client’s drilling and blasting process and collect baseline data on current drill and blast designs. The team observed and instrumented four baseline blasts, collected excavator time study data and fragmentation analyses, developed a drill and blast plan, performed crack and joint monitoring, and oversaw the trial design process. RESPEC’s quality control-based design process was based on data collected through a number of high-accuracy mining tools.
The team made several recommendations regarding best practices, blast design, safety, and procedures that were based on the results of the trial blast. RESPEC’s overall recommendations ensure quality control from blast design, to drilling, to charging. RESPEC’s recommendations include further testing of cautious blast designs. Pre-split drilling designs were suggested to pre-split the rock, avoid overbreaking the walls, and create safe, final pit slopes. For equipment, RESPEC recommended recalibrating or upgrading the Boretrak/Quarryman 3D highwall profiler, in addition to purchasing a downhole camera for better investigation in underground areas of caution.
RESPEC’s team used several high-accuracy tools to evaluate drilling and blasting operations. The team helped the client understand better ways to collect baseline data and identify variables that should be adjusted in the drill and blast design or for operating practices. RESPEC’s approach to addressing the upper bench will help the operation adhere better to the life of mine plan. RESPEC’s experienced team provided expert suggestions and high-accuracy capabilities to overcome significant challenges while sharing a great deal of professional know-how to ensure the future success of a major limestone project.