Uranium strike off Canterbury may spark mining on huge scale

Press, 22 December 1978, Page 1

Uranium strike off Canterbury may spark mining on huge scale

Wellington reporter

A big uranium field, possibly the largest known, has been discovered off the east coast of the South Island on the Chatham Rise.

Joint research by New Zealand and West German scientists has confirmed the presence of uranium over an area 400 km long and 40-50 km wide. The uranium is associated with rock phosphates scattered patchily over the area. On 21 analyses of 689 samples, 200 parts of uranium per million parts of rock (.02 per cent) have been found, rising to 500 parts (.05 per cent) in some samples.

The percentage is well above the 100 parts per million which is, roughly, regarded as the basis for commercial mining of uranium on shore. Uranium deposits have never been exploited off shore. That uranium exists on the Chatham Rise has been suspected for several years,

but the quantity is surpriS' ing.

the deposit’s profitability will depend on extraction costs, but the present world price of SUS4O per lb, and hopes for buoyant markets in future, bode well. Dr D. J. Cullen, a marine geologist in the Oceanographic Institute of the D.S.I.R. in Wellington, said that most rock phosphate deposits, such as those on the Chatham Rise, did contain some uranium.

The D.5.1.R., working with the West German research vessel Valdivia, took samples during October and November. Of the 689 samples taken, half have gone back to West Germany and the rest are being analysed in Wellington.

Several hundred analyses would be needed to esti-

mate the uranium’s full potential, Dr Cullen said. However, the initial results were very promising.

No prospecting or mining licences are held over the Chatham Rise. Global Marine used to hold a prospecting licence, but this lapsed several years ago. The samples taken by West Germany and the D.S.I.R. were taken without a prospecting licence, on the basis that they were “scientific” rather than “prospecting” samples.

Mr L. Jones, the chief mining engineer of the Mines Division of the Ministry of Energy, is dubious about commercial prospects. Even when depositswere as high as those found, profitability was uncertain in the rough seas, he said. The South Africans had

found it profitable to extract at .01 per cent, but their uranium was easily accessible in the boulder and dust tailing at the goldfields.

A West German mining firm, in conjunction with several New Zealand companies. set out in July last year, to prove the value of uranium deposits in the lower Buller Gorge, which had first been prospected in 1959.

The survey was described as a “brief reconnaissance” of the deposits in the area —some of which were found to be rich in uranium ore but not of sufficient size to warrant mining—and it was to have continued this summer on a bigger scale.

However, no report of activity in the region has come to light.