Stockton mine

The Stockton mine is a sprawling open cut coal mine located approximately 25 km north east of Westport and just inland from the small township of Granity on the West Coast of the South Island.

The mine, New Zealand’s largest, produces bituminous coal and is owned by the government-owned coal company, Solid Energy.

Background
The mine is operated by Stockton Alliance, a partnership between Solid Energy and Downer EDI Mining NZ. Coal is sourced from a number of pits on the high altitude plateau.

In an April 2009 brochure Solid Energy stated that the mine produced approximately 2 million tonnes of coking coal a year, mainly for export to Asian steel mills. The very low ash content of the coal meant that it was also in demand for making activated carbon and silicon metal. The company expected the Stockton operation to continue production at those levels for up to 20 years (to 2028). Up to six trains a day on KiwiRail's Midland railway line carry coal to Lyttelton Port of Christchurch.

In its 2011 Annual Report, Solid Energy announced that it had achieved major increases in overburden removal and coal extraction at Stockton. The company anticipated that semi-soft coking coal blends would be increasingly important in exports as the $60 million Cypress extension at Stockton, and other resources, would come into production over the following three years. [In December 2011 Solid Energy applied to the Buller District Council and West Coast Regional Council for 12 resource consents relating to the Mount William North mining Project on the Stockton Plateau.] Solid Energy also stated that Stockton Alliance, its joint venture arrangement with Downer EDI Mining (NZ) Ltd, had made good progress. Improvements were being made designed to lift production back towards 2.0 million tonnes a year, while mining deeper and more complex resources.

In 2012, Stockton Mine workers didn’t have the same redundancy fears as those employed in underground mines such as Spring Creek and Huntly East. The strategic and structural change proposals outlined by Solid Energy in August did however make reference to, “Optimising production and minimizing costs at Stockton Mine to generate additional cash.”

Environmental issues
Opencast mines like Stockton are more environmentally damaging than underground mines. Acidification of water is a particular problem at Stockton because of the high rainfall and the natural acidity of the rocks. Solid Energy CEO Don Elder stated in January 2012 that, “About 10 years ago, we acknowledged that Stockton's environment had been mismanaged and that we had to change the way we operated. Since then, we've worked with interested people from the local community, carried out a great deal of basic science to understand the challenges, developed solutions and built those into the way we mine.”

In October 2009 the Parliamentary Commissioner for the Environment produced a report “Stockton revisited: The mine and the regulatory minefield” in which she commended Solid Energy for having established a comprehensive Environmental Management System at Stockton Mine to manage the impacts of the mining operations on the surrounding environment. In particular the Mangatini Stream had become less turbid and the Ngakawau River had become much less acidic. The report also outlined land rehabilitation practices being carried out by Solid Energy at Stockton.

The commissioner, however, expressed concern that because Stockton Mine operated under one of the old mining licences issued prior to the introduction of the Resources Management Act it was under no legal obligation to go beyond the requirements associated with the “old” licences. Solid Energy is entitled to sell its “old” licences to private companies [and in fact the present government has stated its intentions of carrying out a partial privatization of the company].

Solid Energy’s 2011 Annual Report provided information about the environmental impact of the Stockton Mine. It stated that a significant improvement had been made in the impact of the mine on water quality. The report also stated that the total disturbed ground at Solid Energy mining sites was 1,656 ha and during the year the rehabilitation of 36 ha had been completed (cf 66 ha in 2010). At Stockton, 17 ha had been rehabilitated through the transfer of native seedlings and vegetation salvaged from the mine. Another 16 ha of land had been prepared for final vegetation in 2012.

Restoration of animal populations at Stockton appears likely to be problematic. Giant land snails, Powelliphantia augusta, were removed from 5 ha of of the Mount Augustus ridgeline in 2006 before their habitat was mined. Five years later, eight hundred of them died due to the malfunctioning of the Department of Conservation fridges in which they were being kept. Landcare Research officers stated that the snails that had been translocated to new sites in 2010 were breeding too slowly for the populations to survive.

Project Details
Owner:  Solid Energy Location: just inland from Granity, north-east of Westport Coordinates: -41.661884,171.87644 Status: Operating Production capacity: 2 million tonnes a year Type of coal: Bituminous Employees: 500 plus approximately 200 contractors Main markets: Exported to steel mills in India, China, Japan, South Africa and Brazil.

Related SourceWatch Resources

 * New Zealand and coal
 * New Zealand Mining Industry Association
 * Solid Energy