Case studies

Tailings dam construction February 2021, Hellyer, Tasmania.

Eastern arm tailings AMD sampling.

The salmon nursery adjacent to the Huon estuary in Tasmania is expected to commence operating in January 2019.

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Passivated pyrite from eastern arm.

Mine closure management, Highway Reward Mine, north Queensland (2012-2015)

This project involved reviewing the operational and closure history of an open cut mine in northwest Queensland to help the owners understand the risks associated with site stabilisation and consequently development of long-term closure plans and risk assessments. It included integration of groundwater issues, surface water management, waste rock dump capping, AMD formation, geotechnical pit wall stability and development of revegetation programs. Assessments indicated that closure decisions made decades earlier were contributing to AMD formation and potential offsite impacts.

Environmental approval for a new tailings storage dam, Savage River Mine, northwest Tasmania

The largest dam built in Tasmania since the Gordon-below-Franklin Dam, the South Deposit tailings storage facility was not a standard dam and had been designed to allow supernatant water to flow through the dam face to pick up alkalinity from specially-sourced and deposited rocks. This in turn neutralised long-term acid drainage and improved downstream water. The environmental approval process across three tiers of government was long and arduous, with validation requirements of the Labor-Greens government alliance in Canberra and the Labor-Greens government in Tasmania quite onerous. Ecological management plans and inductions for compliance with the Environmental Protection and Biodiversity Control Act 1999 were critical to gaining approval.

Approval for a multi-stage open-cut and underground mining operation, Burns Peak, northwest Tasmania

This was a difficult approval because the client did not have detail available on mining plans, especially for the proposed third stage open cut mine. Detailed waste rock management plans were developed to reduce and manage AMD development and to cap a poorly constructed waste rock dump to reduce long-term AMD seepage from the dump.

Approval for an exploration decline, northwest Tasmania

With approval required to facilitate underground exploration to determine the feasibility of the Fossey underground mine, assessment of AMD potential and development of management plans for AMD, groundwater and surface water associate with the decline construction were crucial.

Approval for the Fossey underground mine, northwest Tasmania

Coordinated, drafted and developed a DPEMP for an underground mining and polymetallic processing operation. Successfully managed the approval process.

Approval for mine life extension, Savage River Mine, northwest Tasmania

This was initially a pre-feasibility assessment to assess the options for extending the life of a magnetite mine. Partial block cave and deeper open cut options were assessed.

Once the risk associated with underground options were deemed as too high, compared with the open cut, the environmental aspects were assessed for developing deeper long-life open cut operations along the orebody strike length. These centred around mine waste rock management, tailings production and management, and surface and ground water management. The development of plans to assess the potential for developing AMD and managing pyrite in waste rock and sulfides in tailings were critical in obtaining environment approval for the mine life extension.

As a result, a mine slated for closure in 2009 continues to operate in 2018.

Environmental effects report for conversion of eel aquaculture farm to salmon broodstock facility, Bagdad north of Hobart, Tasmania

Ongoing.

Noise assessment and report for a salmon hatchery, Huon Valley, southern Tasmania

Caloundra Environmental was engaged to undertake a noise survey at Huon Aquaculture’s Forest Home hatchery as required by a condition of its environmental approval. The operation had also been subject to a number of noise complaints since opening.

The assessment included measuring sound pressure levels at complainants residences and other nearby receptors to determine the veracity of the complaints and the activities compliance with its environmental approval conditions. By utilising one-third octave frequency measurements, the major noise sources were identified and recommendations provided to attenuate the noise emissions.

Visual impact assessment for a salmon grow out facility, Port Huon, southern Tasmania

As part of the environmental approval for the Whale Point salmon nursery a visual and landscape assessment was carried out to determine the potential visual impact of the proposed nursery from the nearby town of Port Huon and the Huon Highway. Recommendations were provided on measures to mitigate potential visual impacts from the nursery building.

Draft annual environmental management reports

Environmental Management Plans (EMPs) and repots are typically required for most aspects of developments these days. The core components are the identification of environmental aspects, assessment of hazards and risks, development of management protocols and formalising them in the EMP. Provision of monitoring plan and instituting management feedback loops completes the program.

EMPs have been developed for many sites to meet regulatory requirements, pre-approval requirements post approval requirements and have covered:

Rehabilitation and closure options report for Que River Mine, northwest Tasmania

Rehabilitation and closure options for a mine on care and maintenance to facilitate compliance with an Environmental Notice. The review examined the feasibility and cost of a number of options to reduce and treat AMD development associated with the site.

Environmental licence approval for Ivanhoe Cloncurry Mines, Selwyn, northwest Queensland

After the Selwyn mine was purchased from receivers, it was necessary to renew existing but “lapsed” environmental licences associated with the site, institute monitoring programs, maintenance programs, and reporting programs to achieve compliance with environmental legalisation. A program of slow but steady rehabilitation on disused areas of the site was instituted.

Environmental due diligence report for Bass Metals

A due diligence report was compiled for Bass metals on the environmental risks associated with the Hellyer mine when the Bass Board was considering the purchase of the site in 2008.

Waste rock management audits for Mt Bischoff Mine, northwest Tasmania

Developed a waste rock management plan to comply with conditions precedent to gain approval to mine Mt Bischoff in northwest Tasmania. Audited waste rock management on-site with reports provided to the company for submission to the Tasmanian EPA.

Environmental, water, waste rock and tailings pre-feasibility study, Southdown Joint Venture, Albany, southwest Western Australia

Managed the environmental approvals program in Western Australia for the Southdown Iron Ore Project through scoping and PFS phases, including the Malaysian pellet plant component and a desalination plant at Cape Riche on the Southern Ocean.