UNDERGROUND DRILLING
Byrnecut mobilises for Wolfshag development
Mobilisation of Byrnecut ’ s newest offshore contract for Canadian-owned Corp B2Gold recently commenced . The contract is located at the Otjikoto operation and specifically covers the new high grade Wolfshag Underground Mine , approximately 320 km north of the capital city Windhoek , Namibia . Wolfshag is Byrnecut ’ s first mining contract in Namibia and the team includes 34 experienced expatriate miners from Australia , Indonesia and parts of Africa working jointly with 58 appointed local Namibians and B2Gold Otjikoto staff to ensure the success of what is the first underground gold mine in Namibia .
Byrnecut said the client is currently upgrading the camp to accommodate all Byrnecut employees and ensure that it is a first-class facility . The contract for Wolfshag is valued at US $ 112 million and consists of both development and production , including a total of 10 km of development and a total material movement of 3.2 Mt . The underground fleet is mainly from Sandvik Mining & Rock Solutions and currently consists of one DD422i DC jumbo , one DD422i jumbo , two LH517i loaders , three TH551 trucks and a DL432i production drill rig .
In its full year 2021 results , B2Gold stated : “ Development of the Wolfshag underground mine continues to progress with ore production expected to begin in the first half of 2022 . The initial underground Mineral Reserve estimate for the down-plunge extension of the Wolfshag deposit includes 210,000 oz of gold in 1.2 Mt of ore at 5.57 g / t gold .”
from the operator ’ s deck , with no manual procedures .”
Zinkgruvan Simbas on 4G LTE network
Looking at production drilling advances , Zinkgruvan Mining is feeling the effects of teleremote drilling using a 4G LTE network and Epiroc ’ s Simba E7 rig at its underground base metal mine , according to a case study from the Sweden-based OEM . In early spring 2021 , Zinkgruvan Mining , working in conjunction with Epiroc and IT , and telecom operator Telia , first connected its Simba E7 rig to an LTE ( Long Term Evolution ) network . Since then , remote production has taken off like a shot in the areas where the LTE network has been commissioned , according to Epiroc , while acknowledging this is still in trial mode .
The mine has a total of four Epiroc Simba rigs , with , at present , one of these connected via Simba Teleremote , some 350 m underground . In the future , operators may move to an office 800 m underground to get closer to the rig . “ So far , we ’ ve drilled seven pallets remotely ,” Operator , Jocke Lindblad , said . “ It runs very smoothly , and as soon as we find something that doesn ’ t work , I can call the Epiroc service engineer who has been there from the start .” Lindblad monitors the rig from a quiet above-ground office .
The fact the operators do not need to drive down into the mine on a regular basis means they can drill an average of four hours more per day , according to Epiroc . In purely technical terms , Lindblad can operate the rig from an office in the same way as he would down in the mine . The screens and levers are the same as on the rig . “ The only difference is that I can ’ t hear the drill ,” Lindblad said . “ But you do have to keep a close watch on the measurement values on the display .”
Epiroc said : “ Building a dedicated LTE network has been a challenge . It is much harder to bring together a design in a mine than above ground . However , the choice was easy .”
Craig Griffiths , Mining Manager at Zinkgruvan Mining , said the company , a Lundin Mining subsidiary , looked at running automation via Wi- Fi , but decided against this as it wanted the network to work for at least another 10 years and be able to handle the demands of the future . He is convinced the investment puts the mine in a good position for years to come .
“ This will give us better control over our production and reduce our costs ,” he said . “ It feels really good . But the greatest gain will be in respect of safety , with our employees having to spend less time in the mine .”
While the Simba occasionally – under Lindblad ’ s supervision above ground – changes position for a new drill hole , Mattias Dömstedt , Technical Production Coordinator , and Håkan Mann , Project Manager , explain how the technology works , and how the work of installing it has progressed . “ Once complete , the project will have seen about 70 remote radio units , ie transmitters and receivers of radio signals in the LTE network , installed in the mine , providing coverage of around 70 km ,” Mann said . “ The LTE network will then be extended as the mine expands . The portion of the LTE network currently in operation covers around 15 km .”
By then , hopefully some time in 2022 , it will be possible to run another Simba rig by
teleremote , provided that RCS4 can be used via LTE , Epiroc said . But Dömstedt , Mann and their colleagues on the project have already come a long way since the very first tests in December 2020 , which were designed to show whether teleremote over the LTE network worked at all . Dömstedt said : “ We were in Epiroc ’ s workshop 800 m down in the mine . We had a remote station in the room next to the rig , and we looked out to see if it was moving around on the rig , and it was .”
The company sees LTE opening further possibilities . For example , Zinkgruvan has collaborated with Mobilaris to set up unique , full site coverage , communication and positioning infrastructure at the site , a project that led to the development of Mobilaris Virtual Tag™ , which is running on LTE .
Mann said : “ As we are the first to build something like this , we haven ’ t been able to ask anyone for help , we ’ ve had to solve all the problems ourselves along the way .” According to Mann , the key to success lies in clear , short decision-making paths and a responsive way of working where everyone , including partners and suppliers , takes responsibility and is fully committed .
“ This is exactly our approach to this project ,” he said . “ Everyone involved has had direct contact with each other . Even the operators have been able to talk directly to those building the network .”
The close cooperation with Epiroc has been crucial to the project , according to the OEM . “ Our development has gone hand-in-hand with that of Epiroc ,” Mann said . “ They ’ ve known that we were going to build an LTE network and then developed their teleremote system accordingly .”
Despite the fact Zinkgruvan is still a long way from bringing home the project , both Mann and Dömstedt are proud of what they have achieved . After completing 6,500 remotely drilled metres , they say the drilling is more efficient than ever , while the operators are satisfied and happy . The target is to reach 10,000 m , after which a thorough evaluation of the technology will be carried out .
IM
In 2021 , Zinkgruvan Mining , working in conjunction with Epiroc and IT , and telecom operator Telia , first connected its Simba E7 rig to an LTE ( Long Term Evolution ) network
52 International Mining | JUNE 2022