Backfil ling of excavated Sub Level Open Stopes has been underway since
March 1989 and as at December 1992 some 1 100 000 cubic metres of
Cemented Aggregate Fill have been placed. During these three years
significant developments in fill quantities, types and cost have taken
place.
Operational improvements have reduced the quantity of Cement
Aggregate Fill by 40 per cent. These results have been achieved by:
rescheduling stopes,
designing smaller primary stope, and
use of uncemented rockfill.
Unit cost for Cement Aggregate Fill have fallen in the order of 50 per
cent through:
improving fill hole reli ability,
simplified barricade construction procedures,
reducing the cement content,
substituting dune sand for deslimed mill tailings,
improved maintenance at the Backfill plant, and
renegotiated site freight agreement.
This paper will review the historical developments of backfill use at
Olympic Dam.