Quantification of the effect of inaccurate drilling on the risk of poor fragmentation and increased blast hazard

A blast auditing project was done on an open pit platinum mine in Rustenburg, South Africa to monitor the drilling accuracy of the boreholes using borehole survey instrument (MDL Boretrak MK3TM). The overburden being mined is a Norite rock type and the blast design blast parameters recorded are shown in Table 1. Typical blasts use about 400 holes.