The New Zealand Coal Resources Survey (NZCRS) systematically explored New Zealands coal resources and carried out mining. utilisation and environmetal studies between 1975 and 1979. This programme in turn drew on the knowledge base of a National Coal Survey undertaken jointly by Mines Department and DSIRs NZ Geological Survey and Dominion Laboratory between 1936 and the mid 1950s. This earlier survey established the immediate mining prospects in Greymouth, Reefton. Buller, Ohai, Huntly and Kaitangata coalfields.
The NZCRS w die largest mineral exploration programme ever carried out in New Zealand, discovering new coal resources of some 14 billion tonnes of inground coal. Over 1800 holes were drilled. which together with the associated technical and mining studies involved expenditure of over $35 million.
The NZCRS was driven by :
• electricity demand projections that requited two i000 MW coal fired thermal power stations in the south Aucklaid area auckland area in addition to the Huntly station, then under construction.
• the vulnerability of New Zealand’s economy to the cost of Imported oil exposed by the OPEC-driven oil shocks of the 1970s. This eventually lead to the investigation of the South Island lignites by the Liquid Fuels Trust Board as a source of petroleum substitutes.
• the vision of the then Secretary for Mine’s, Ian Dick, who realised the value of establishing energy resources for long-term Securlty of supply.
Coal exploration drilling in the Waikato, photo ; A Sherwood
The Coal Resources Survey had five component :
• Exploration and geologicl resource assessment
• preliminary mining feasibility studies
• evironmetal constraint assessment
• coal propeties and use assessment
• cLassification of resources
The principal discoveries were:
• two Large deposits of opencast and underground mineable subbituminous coal resources in the Waikato, Maramarua and Ohinewai
• a large resources of deep sub bituminous coal in the Waikato
• a large resources of opencast and underground mineable sub-bituminous coal in Taranaki
• a large resources of bituminous coal in greymouth Coalfield. the largest block of which is currently being mined for export
• a large resources of hlgh-quality bituminous coal in Buller Coalfield
• a world-class lignite resources in Central Otago and Eastern Southland which has the potential to sustain a high proportion Of New Zealands energy needs if necessary.
Coal Exploration in the Greymouth Coalfield using a helicopter located rig. Photo : Lime and Marble Ltd