Case Studies
Our recent projects
Rotowaro Opencast Mine
Client
Lead Contractor - Leighton Contractors
Rotowaro Opencast Mine
Duration/SizeTo remove 2.8bcm of Overburden per year
LocationHuntly, Waikato
Technical Aspects
Open-cut mining operation
Overburden removal
Unseasonally difficult weather conditions resulted in some downtime.
Ohai Opencast Coal Mine Pits
Client
Solid Energy NZ
Contract
Ohai Opencast Coal Mine Pits 16 & 17
Duration/Size
14,000,000 bcm (bank cubic metres) over five years
Date
March 2005 to March 2010
Location
Ohai, Southland
Subcontractors
Orica – Drill and blasting
Transport Services Ltd – Coal haulage
Value
Approx $65 million
Technical Aspects
Open-cut mining operation
Overburden production 2,800,000 bcm per year
Coal production 300,000 tonnes per year
Challenges
Ohai presents a unique and complex geology. It has been mined using underground methods. This results in its own challenges:
Dealing with old workings, unstable ground, and collapsed roofs.
The Southland weather conditions are unique, and result in downtime due to bad weather.
Meeting the challenges
Stevenson Mining have successfully overcome these challenges by implementing streamlined production and water management systems to allow the team to progress the job as soon as possible after rain.
This ‘can-do’ attitude will enable the team to complete the job to a high standard, on time and within budget, delivering the best possible outcome for the client.
Our past projects
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Glencoal Energy (Subsidiary of Fonterra Co-operative Group)Contracts
Kopako, Renown and Pirongia Coal Mines
Size9,500,000 bcm
DurationSeven years (1998 – 2005)
LocationMaramarua
SubcontractorsNil
ValueApprox $20 million
Technical AspectsLarge scale open cut mining contracts totaling more than 15,000,000 bcm to uncover multi coal seams. Materials included papa mudstone and fireclays.
Glencoal Energy (Subsidiary of Fonterra Co-operative Group)
Contracts
Original Kopako coal mine (formerly named Kopuku)
Size3,000,000 bcm per annum
DateStarted 1948
LocationMaramarua
SubcontractorsNil
ValueApprox 17 million tonnes of coal
Duration20 years
Technical AspectsLarge scale open cut mining contracts totaling more than 17 million tonnes of coal. Materials included papa mudstone and fireclays.
Oceana Gold
Contract
Macraes Gold Mine
Size
250,000 bcm to embankment plus 170,000 tonne rock mattress
Date
2003-2004
Location
Macraes Flat, East Otago
Subcontractors
Bruce Wilson Ltd – embankment drainage
Value
Approx $3 million
Duration
18 months
Technical Aspects
Tailing dam embankment construction
