During and
immediately after the Second World War the government gradually took over all the large
coal mines in the Buller coalfield including Denniston, Millerton and Stockton.
By 1948 there was an imaginary demarcation line along the Ngakawau River
– all the mines to the south were state-owned, while those to the north were
privately owned.
There was a
buoyant market for coal in the late 1940s and early 1950s, and the Seddonville
mines prospered. After 1956, though, demand slumped as many customers changed to oil. The smaller private mines gradually
closed as they were unable to find markets for the coal they produced.
Charming Creek mine
The
Charming Creek mine had become one of the largest privately owned mines in the
country – certainly the largest producing bituminous coal. The change to
hydraulic mining allowed the mine to survive until the 1980s, although with far fewer workers. Its coal was trucked from the mine to a dump at
Seddonville, and then transported by train.
In 1965 the
Charming Creek mine was taken over by the Bridgevale Group (later Bridgevale
Mining), a precursor of Bridgecorp. In its 1980 prospectus the company
predicted a bright future, with enough coal for another 30 years.
Although
coal still remains in the ground, it proved impossible to sell.
Seddonville coal is characteristically high in sulphur – generally 5%, and
sometimes up to 6%. With increasing environmental awareness, burning
high-sulphur coal was banned in many urban areas as well as in organisations
such as hospitals and schools.
The last
major customer was the dairy factory at Karamea. When the mine closed in 1986
it had only four staff.
Is there any coal left?
The New
Zealand Coal Resources Survey systematically evaluated all areas of coal in New Zealand in
the 1980s. A detailed study of the Seddonville area, including new drilling,
concluded that coal was present only as lens-like pods rather that as a
continuous seam: 'The chances of discovering a major new coal deposit
in the sector are extremely slim'.
There are
still small patches of coal that might be mined, including some in the Charming Creek workings. But the only likelihood of future mining is if a market is found for coal
that is exceptionally high in sulphur.