The mine operators and management are responding by installing pumping equipment to remove water from the mine.

In a statement Yancoal said production from the mine was likely to be impacted for at least three weeks but timing on the commencement of coal mining remained uncertain.

“Middlemount will seek to continue to undertake certain works in areas which are unaffected by the flooding,” it said.

Peabody Energy and Yancoal Australia are joint owners of the Middlemount mine.

Production was suspended at the Yarrabee mine for a period over the weekend and following an inspection of the mine normal operations are expected to commence this week.

Yancoal does not expect any impact on production for the quarter from Yarrabee.

Yarrabee recorded more than 360mm and Middlemount 420mm of rain from the event.

Production of run of mine and saleable product coal at the Yarrabee for the December quarter was 1.2 million tonnes and 867,000 tonnes respectively in the December quarter and 3.14Mt and 2.43Mt respectively for the full year.

The coal handling and preparation plant achieved a weekly production record of 73,000t of product during October.

The mine finished the year with a very strong quarter and month, with ROM production of 602,000t and saleable production of 407,000t in December.

The surge in production combined with low railings and sales has led to a significant build-up of product stocks at the mine and load-out facility.

Railings of coal to the port were impacted by a significant number of train cancellations by the track operator due to heavy demand and track availability issues during the quarter.

As a result coal transported to the port during the quarter was well below contracted volumes.

A mining lease was granted in late October that will enable the development of a production area called the YEN pit during 2013.

The area will underpin the operation at the mine for several years.

While Yancoal’s Middlemount mine continued to perform below budgeted expectations, ROM coal output increased and reached 804,000t with saleable production of 639,000t during the December quarter.

Much of the improvement was due to the substantial geotechnical remediation undertaken in the last half of the year.

There have been some issues with one of the product screens in the CHPP, with plant designer, builder and operator Sedgman working on overcoming the problems.

It led to a delay in the performance testing of the 700 tonnes per hour feed rate to the plant until late January.

Coal sales are increasing with a number of sales of both coking and pulverised coal injection coal into the spot market.