Kevin Slemko, Major Drilling Group International Inc., Canada, outlines the process of supporting the delivery and ramp up of a new hydrofracking programme for Freeport Indonesia at the Deep Mill Level Zone mine.
L
ocated in the highlands of New Guinea and in the Indonesian Province of Papua is Freeport Indonesia’s Deep Mill Level Zone (DMLZ) underground mine. Known as one of the world’s largest copper and gold deposits, DMLZ is found below the Deep Ore Zone (DOZ) mine where 2021 production rates are expected to average approximately 60 000 tpd of ore from several production blocks. In 2022, an increased 80 000 tpd of ore is expected.1 It is here that Major Drilling has partnered with Freeport, using specialised drilling techniques to support hydrofracking and mitigate mine-induced seismic activity in the DMLZ. Major Drilling provides block cave preconditioning services and
equipment to help mitigate the mining-induced seismic responses from mining in the DMLZ (Figure 1). As caving operations have progressed in the DMLZ, mine induced seismic responses have increased, leading to several changes, including the use of hydrofracking to help mitigate issues.
The project Undercutting began in August 2015 and progressed until the seismic response to the caving process began to increase. Those initial seismic events caused damage to tunnels at the mine, mainly around the extraction and undercut levels. Realising the
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