Description
This underground nickel mine in the Midwest United States is relatively young with only a few years of production blasting. The operation is employing a sublevel stope mining technique. The operator purchases Dyno TITAN® RU emulsion and electronic detonators for blasting. The customer was experiencing poor blast results over a substantial period of time. When the customer first contacted DynoConsult® for assistance, the concern was the under-breaking of the ore which left valuable material along the ribs. At that time the mine engineers were looking for guidance on the delay times they should be using to improve the recovery of ore. During the site visit by DynoConsult, it was also discovered that there were a few instances of benches and bridges being left in the stope after mucking. In one stope it was estimated that over $1 million worth of ore was left unrecoverable in the stope.
It was also revealed during the site visit that there were issues related to tight digging of the muckpile even though the fragmentation was adequate.