The former Globe Progress Mine, located in New Zealand’s South Island, is a leading example of achieving sustainable outcomes.

By Reefton Restoration Project, OceanaGold, and Ashley Bartlett, Babbage Consultants

Reef1Multinational gold producer OceanaGold is serious about sustainability. However, unlike many other mining companies, OceanaGold’s commitment to achieving sustainable outcomes does not end when their mining operations cease.

Rather, for OceanaGold, the closure of a mine site is simply a transition to a new phase of operations, and a new opportunity to achieve additional important sustainability targets.

The former Globe Progress Mine, located in New Zealand’s South Island, is a leading example of OceanaGold’s commitment to achieving sustainable outcomes after mining operations cease.

OceanaGold operated the Globe Progress Mine for about 10 years, and on average, moved approximately 23 million tonnes of material each year. As a result of more than 610,000 ounces of gold being extracted from the site, the depth of the main pit was 275 m below the highest ground surface. However, in 2016, the mine transitioned from an operational phase to closure and a rehabilitation phase and has since come to be known as the Reefton Restoration Project.

Environmentally Sustainable Outcomes

The Reefton Restoration Project is largely focused on achieving environmentally sustainable outcomes. Central to the project is the re-establishment of vital ecosystems in the new post-mining landscape.

In order to achieve this, OceanaGold has already undertaken a large-scale reforestation programme, covering 118 hectares. To date, approximately 700,000 seedlings have been planted, and a further 200,000 seedlings will be planted over the next three years.

The reforested areas predominately include species native to New Zealand, such as Beech and Manuka varieties, to provide homes for local wildlife species and enhance biodiversity outcomes. In addition to planting, the progressive rehabilitation also includes waste rock reshaping, backfilling operations, spreading of topsoil, and pest management, to ensure that the environment is visually integrated into the surrounding landscape

Furthermore, the Reefton Restoration Project includes impressive social sustainability targets to benefit the local community. A major target of the project was to support local community projects and since the rehabilitation phase began, OceanaGold has provided funding for a local socio-economic development officer (NZ$150,000), and further funding for local community projects (NZ$50,000).

They have also provided reinvigoration funding (NZ$50,000) to the local I-SITE visitors centre to encourage tourism for the area. The restoration project also aimed to offer employment opportunities for local community members, and several positions have been filled by local people, while the local and regional economy has also been bolstered through the procurement of goods and services.

Rewarding Experience

Steph Hayton, the Environmental and Restoration Coordinator at OceanaGold, said that working on the project has been a hugely rewarding experience. She stated that working on a project like this has required an adaptive management style whereby research and trial work informs decisions on all aspects of closure.

This includes restoration trials determining rehabilitation methods at the beginning of the operation, all the way through to the establishment of passive treatment trials for long-term management of onsite water when the first went into closure.

This approach has meant innovative techniques creating some great long-term solutions. While some aspects of closure have been easier than others the work towards closure has been extremely satisfying, with rehabilitated areas of the site now hosting many native bird species including the nationally vulnerable South Island Kaka.

Babbage Consultants Limited has been providing support to OceanaGold on the project. Amongst several services provided to OceanaGold, Babbage has conducted ongoing water quality monitoring and guidance on wetlands for a lake side margin and also a treatment wetland to enhance downstream water quality outcomes.

Dr Grant Allen, a senior environmental scientist at Babbage, says that working together with the team at OceanaGold has been very rewarding. Reflecting on the project, Grant said that it is great to see companies, such as OceanaGold taking its responsibility for the environment seriously and then proceeding to go above and beyond to demonstrate that mine sites can be properly rehabilitated.

Looking ahead, he said that it would be fantastic to see more mine operators following in OceanaGold’s footsteps, taking up the challenge of rehabilitating their former mine sites to allow the environment to recover and prosper.

While OceanaGold has already made many significant environmental and social gains in the rehabilitation phase, the Reefton Restoration Project is not due to be completed for a few more years. However, the project is already showing signs that it represents a new gold standard for mine rehabilitation.

In the coming two years, the project team will continue their environmental work, and the reinstatement of adjacent historic tracks. Upon completion, OceanaGold will hand back the land to the New Zealand Department of Conservation in accordance with their council consent.

OceanaGold is a multinational gold producer with global operating, development and exploration experience. Babbage Consultants is a New Zealand-owned multi-disciplinary practice offering tailored consultancy services across architecture, engineering, environmental science and ecology, land development and project management.