The company, which is reviewing submissions to its proposal for the extension, estimates that the colliery extension will employ 120 staff for 14 years.

Its existing major project approval provided a relatively short-term approval life for the colliery, with an expiry date of December 31, 2016.

“Geological features subsequently identified during mining of the approved secondary extraction area (Domains No.1 and No.2) will prevent LakeCoal from recovering all of the resource approved for mining under MP10_0161,” according to its environmental impact statement.

“It is now estimated that the reserves within the approved secondary extraction area will be exhausted by late 2013.

“If access to further coal reserves is not approved by this time the colliery will be forced to shut down, affecting employment and the supply of coal to … customers.”

The Chain Valley colliery is an underground coal mine at the southern end of Lake Macquarie, managed and operated by LakeCoal on behalf of the Wallarah Coal Joint Venture.

Underground mining has occurred at the Colliery since 1962, extracting coal from three seams – the Wallarah, Great Northern and Fassifern, with current mining activities limited to the Fassifern seam.

The Chain Valley colliery mining extension includes an extension of the currently approved extraction area to allow underground mining to continue within the Fassifern Seam and an increase of the approved maximum rate of production, from 1.2 million tonnes per annum to 1.5 Mtpa of run‐of‐mine coal.

It would seek an increase in the approved hours for haulage of coal from the colliery on private roads to Delta Electricity’s Vales Point Power Station from 5.30am-5.30pm, Monday to Friday to 24 hours a day, seven days a week.

No change to the approved hours of haulage on the public road network is sought.

Minor upgrades and modifications to existing approved infrastructure, and an extension of the approved mining by a period of approximately 14 years to about 2027, is also being sought.