A MISERABLE June half-year production effort has translated in to an equally miserable profit performance for the Ranger uranium miner Energy Resources of Australia.

The June-half profit by the listed Rio Tinto subsidiary plunged 82 per cent from $127.6 million to $22.7 million as revenue collapsed from $336.1 million to $209.6 million.

The previously flagged sales slump was due to production of uranium oxide falling 36 per cent to 2695 tonnes. The average realised received price was also weaker at $US44.79 a pound, down from $US48.02 a pound in the previous corresponding period. The stronger Australian dollar also took its toll on earnings.

The interim dividend has been slashed to 8¢ a share, fully franked, down from 14¢ a share previously.

On a more positive note, ERA said that its uranium sales would be heavily weighted towards the second half of the year.

The production slump was due mainly to a hefty reduction in the grade of ore delivered to the Ranger mill because access to part of the open-cut was restricted due to instability. There was also the impact on vehicle movements of heavy rainfall.

ERA said that work continued on the feasibility study for the development of a heap-leach operation at the Ranger mine. The environmental assessment process under Northern Territory and Commonwealth regulations ''is likely to be completed in the first half of 2011'', it said.

Separate studies in developing the resource at Ranger 3 ''Deeps'' were finished and a decision on an exploration decline [tunnel] was due in the September quarter.

ERA said that, in the short term at least, the uranium market appeared to be well supplied due to power utilities holding adequate inventory and increased production from Kazakhstan. It also said that the financial crisis had led to delays in nuclear reactor building in most regions, with China the exception.

ERA shares fell 56¢, or 3.91 per cent, to close at $13.78.