Ulan Mine: mining & infrastructure - geology & coal reserves

mining & infrastructure

geology & coal reserve

UCML
Stratigraphic Profile

Ulan Coal Mines Limited (UCML) is located within the Western Coal Fields of the broader Permian Illawarra Coal Measures. Specifically the coal resource targeted is the Ulan seam sequence of the coal reserve. This seam is at the bottom of the Permian Illawarra Coal measures, outcropping in the southern areas of UCML Colliery holdings.

Ten coal seams occur at Ulan Mine: eight above the Ulan coal seam and one below. These seams range in thickness from 0.4 to 8 meters. Apart from the Ulan seam, all of the other seams are considered uneconomic in the current market due to their high ash content. The Ulan seam is the only coal seam of economic significance and is the target seam for mining. The Ulan seam consists of four working plies (not all present together), which will be mined by Ulan Mine. These working sections are interbedded with clay stone and siltstone horizons. The Ulan seam in the mining area dips uniformly towards the north-east at between one and two degrees. It is planned to mine the full seam that is present in this area.

In underground operations the lower three-metre section of the Ulan seam, this is referred to as the “D Working Section” (DWS), is mined to produce Ulan “premium” coal that has an ash specification of 12.5%.

In the open-cut operations, the full seam (which includes a clay band) can be mined and then washed to produce 16.5% ash “standard” coal. However, because this coal has a limited market, an alternative is to mine above and below the clay band in a process known as ‘split seam mining’. Above the clay band, seams are mined to produce “domestic” coal, which is beneficiated to produce a 22% ash product. Below the clay band, the lower bench (which includes the upper section of the DWS) is mined to give “thermal” coal that contains 14% ash.