Mining in New Zealand - Environmental Issues

Environmental Issues

Environmental issues with mining include acid mine drainage and large scale modifications to landscapes. Acid mine drainage from coal mining is a serious problem in New Zealand. It is estimated to adversely affect 125 kilometres of streams mainly in the Buller District of the West Coast Region of the South Island. There has been very little remediation of acid mine drainage. Regulation of AMD has been vague and enforcement is lacking. AMD from mines that were established before the Resource Management Act 1991 has been allowed to continue.

The Tui mine in the Kaimai Range which closed in 1973 is considered one of the worst toxic waste sites in New Zealand and the government has allocated almost $10 million for cleaning up the site. Structural failure of historic underground mine workings have led to subsidence, cracking and collapse on properties in Waihi, a township that has built up around the current open pit. The Stockton Mine on the West Coast of the South Island, has historically been responsible for acid mine drainage in adjoining waterways, and has since built a comprehensive water treatment plant on the Stockton plateau. Stockton poses a threat to some native species, although has carried out significant biodiversity conservation work in the region, and mountaintop removal mining has happened on the site in recent years. Over a one hundred year period Mount Smart in Auckland was mined to such an extent that it is now level with the surrounding land. Several other Auckland volcanoes have suffered a similar fate.

In 2011 arsenic laden soil was discovered in the suburb of Moanataiari in Thames. The area had been reclaimed from the Firth of Thames using mine tailings, mine waste and rubble. Funding from the government was given towards the cost of soil testing.