The lesser known of the two North island coal mines on the North Island for BT Mining, Maramarua, produces annually about 210,000 tonnes of thermal coal.
The mine, operated by major partner Bathurst Resources Ltd (ASX: BRL), has three key clients - Fonterra, New Zealand Steel and Genesis Energy Ltd (NZX & ASX: GNE).
Chris Dyer of Bathurst told the AusIMM NZ Mining Conference in Tauranga last week that the mine in the north of the Waikato, was about 70 kilometres south of Auckland city.
Coal was first discovered there in 1869 and there was small-scale underground mining between 1871-1914. Glencoal purchased the United Coal Co and began mining of the Kokako open cut in 1946.
Then Coal Corporation and Glencoal joined forces to develop the Kopako 1 and two open pits to supply coal to the Meremere power station in 1958 but when that station closed in 1991 the two pits were allowed to flood.
In 2008 Solid Energy dewatered the pits and following successful marketing trials construction of the current mine began in 2014. Last year, with the liquidation of Solid Energy, Maramarua, the nearby Rotowaro mine and Stockton on the West Coast were sold to BT Mining.