The company is bracing itself for lower production levels early next year and is busily trying to mitigate against the effects of the rainfall on its mines.

“Our Hunter Valley mine operations experienced some interruption on Friday evening but overall the adverse impact was minimal compared to the disruptions previously experienced during November and early December due to the ongoing rainfall,” a Coal & Allied spokesperson told ILN.

“For example, rainfall in November was around double the monthly average. This impacted overburden removal and the availability of coal.

“Further rain events would obviously impact and result in a lower level of production through the first quarter of 2011. However, we are working through this to minimise these impacts.”

Extended periods of wet weather have slashed Coal & Allied’s share of total saleable production in the September quarter by 15% year-on-year to 4.29 million tonnes.

Around 13% of calendar time was lost to rain during the quarter, leading the company to revise its full-year production and sales expectation to 25-26Mt, depending on coal chain performance and more favourable weather patterns.

Despite lower than expected production, overall Coal & Allied has continued to target increased overburden removal as part of its plans to increase the Hunter Valley operations and Mount Thorley Warkworth mines to full capacity.

Total overburden movement in the September quarter was 7% higher than both the previous quarter and the corresponding period in 2009.

This activity is being supported by additional equipment that was progressively commissioned during the quarter.

In the short term this additional overburden is driving higher strip ratios, with Coal & Allied’s attributable strip ratio for the year to date 16% higher than in the nine months ended September 2009.