Tag Archives: GreenGold Engineering

Queensland Government backing set to ‘reinvigorate’ Mount Morgan gold mine

Environmental, Mineral processing, Mineral project development, Mining finance, Precious metals, Sustainable mining, Water management, , , , , ,

The Queensland Government has committed funding to “reinvigorate” the Mount Morgan gold mine in the state, backing the tailings processing plans of Heritage Minerals, Treasurer and Minister for Trade and Investment, Cameron Dick, has confirmed.

“From its proud history as the world’s largest gold mine in the early 1900s, Mount Morgan has been under State Government management to remediate legacy environmental and safety risks for nearly 30 years,” Dick said.

“Heritage Minerals’ proposal to establish a tailings processing plant on the site is a gamechanger with the potential to process nearly 10 Mt of existing gold ore tailings, recovering an estimated 263,000 oz of gold and 5,600 t of copper.”

Heritage is planning to do this by leveraging the GreenGold Engineering-owned ReCYN resin-based technology, which has been shown on other projects to reduce cyanide consumption by up to 50% through capturing free cyanide from plant tailings and recycling it back into the leach circuit.

Dick says Heritage’s plans include the construction of a new water treatment plant to lower the level of contamination in the open pit, treat all water captured by the site’s seepage interception system, and help meet regulatory requirements for the release of treated water into the Dee River.

“While the Queensland Government’s support for Heritage Minerals’ proposal through our Investment in Queensland program is subject to the project also receiving Commonwealth Government and private sector financial support, our backing is a key step forward,” he said.

Heritage Managing Director, Malcolm Paterson, said the Queensland Government funding would allow preliminary work of the environmental rehabilitation of the old mine site to recover gold and copper from the mine tailings to now get underway to deliver a project with the potential to support jobs for another 100 years.

“The Mount Morgan mine created so much wealth and prosperity and had wide-ranging impacts, including providing the impetus for the establishment of BP (British Petroleum) as well as the Walter and Eliza Hall Institute, Australia’s oldest medical research institute,” he said.

“During the mine life, about 250 t of gold and 360,000 t of copper were extracted from the mine with about 134 Mt of waste rock and tailings generated. Our project will respect and protect that proud history, and create new jobs and opportunities for the future of Mount Morgan and the broader region.”

Paterson said Heritage has been working closely with the Queensland Government, which has managed the site as an abandoned mine through the Department of Resources, the Australian Government through the Northern Australia Infrastructure Facility and Rockhampton Regional Council on local procurement and job creation.

“All our key permits and approvals, including our environmental authority, are now in place,” he said. “Once we finalise funding and finance approvals with the Australian Government, which we expect within coming weeks, we can commission further preliminary works. These works include an access road, administration buildings and a drain to divert freshwater captured on the site to a freshwater water storage as a new way to lessen acid mine drainage that emanates from the site.

Heritage Minerals smashes Dando Terrier percussive drilling depth record

Mineral exploration, Mining equipment, Mining services, Precious metals, , , , , , , , , , , ,

The Heritage Minerals team, led by Drilling Manager, Shane Charlton, has been achieving depths of 46 m with high-quality 86 mm samples using Dando Drilling’s Terrier percussive drill rig, the drilling manufacturer says.

The depth is a record for the Terrier rig, according to Dando.

Heritage Minerals is currently working on the historied Mount Morgan mine in Queensland, Australia. One of Australia’s oldest mines, Mount Morgan was active from 1882 through to the 1980s. In the process, tens of millions of tonnes of tailings were generated.

Today, these tailings present both a problem and an opportunity; a problem because they were subject to old, polluting technologies for processing gold, but an opportunity because they still contain reserves of gold, copper and other minerals.

Heritage Minerals is employing innovative processing technologies such as ReCYN, developed by partner GreenGold Engineering, to clean pollutants from the tailings and returning them to safe land.

It was this technology and the tailings recovery aim IM recently focused on for an in-depth article on Mount Morgan.

Heritage chose a Dando Terrier rig to sample the tailings at Mount Morgan for several reasons, Dando said.

“Foremost, the unconsolidated geology of tailing fines is very hard to sample with conventional rotary equipment,” it said. “The Terrier’s Duplex Sampling System, which is driven into the ground by a 64 kg anvil and simultaneously cases-off and samples, provides excellent recovery in this type of unconsolidated geology for metallurgical and in-situ density measurements.”

Charlton proved and refined the drilling method he used in the mineral sands of Kalimantan, Indonesia, where he sampled alluvials to over 20 m for lab analysis, Dando says. This is an impressive feat for a rig that has a large user base for geotechnical sampling, standard penetration testing and dynamic probe testing, most often at depths of less than 15 m.

More than doubling this to 45 m was no easy task, Charlton explained: “At depth, it took almost 10 minutes to trip the drive rods and retrieve the sample, but the quality of the sample and the economies in terms of cost per metre offset the sometimes slow drilling.”

Heritage has recently purchased a second Terrier rig from a Dando customer in Australia and Charlton has made some modifications to the design to facilitate drilling beyond the original specifications of the rig.

“We’ve fitted a permanent casing extractor to help pull sample tubes and casing if they get stuck, as well as modifications to assist with tripping rods more quickly,” he said.

To achieve these depths, the team are using a reaming method whereby they sample using an 86 mm windowless sampler tube, and then ream out using a larger 116 mm tube before returning to the 86 mm sampler to continue. This reduces frictional forces along the side of the borehole and abrasive tailing materials, according to Dando.

The percussive hammer system allows sampling without flush, minimising the need for cumbersome mud tanks or air compressors while preventing contamination of the sample or the environment, it added.