The company has applied to the NSW Department of Planning for continuation of mining operations at Cullen Valley via both open cut and highwall mining methods to access an additional resource of approximately 35Mt ROM and the continuation of mining operations at Invincible and an extension north into the East Tyldesley area via open cut and highwall mining methods to access an additional resource of approximately 48Mt ROM.

It is also seeking a continuation of coal supply to the local Mount Piper power station and emergency supply to Wallerawang power station, with flexibility for supply to additional domestic destinations and Port Kembla for export.

Upgrades to existing administration, transport and other infrastructure and construction of the previously approved coal de-shaling preparation plant at the Cullen Valley mine are also being applied for.

Construction of a bridge over the Castlereagh Highway to link operations east and west of the highway and the development of required access roads to the East Tyldesley area as well as construction of a bridge and haul road across the Wallerawang-Gwabegar railway line to permit access to mine the previously approved Hillcroft resource has also been planned.

Coalpac wants to extract the Marangaroo sandstone horizon from immediately below the Lithgow coal seam in the northern coal mining area of Cullen Valley mine. This material would be trucked for crushing on site prior to sale into the Sydney industrial sand market.

The company is seeking to construct a rail loop or rail siding with loading infrastructure to permit transport of product coal and sand products.

It would also seek to integrate the water management of both sites into a single closed system and integrate the management of mine rehabilitation and conceptual final landform outcomes for Cullen Valley mine and Invincible colliery.

The Cullen Valley mine site contains the former operational areas of the Tyldesley and Beaumaris collieries, where underground coal mining commenced in the late 1800s.

A range of open cut and underground mining operations have been undertaken at the site since this time, with activities suspended at various times in the intervening period.

On December 24, 1997, the Lithgow Coal Company (previous owners of the Cullen Valley mine) was granted DA 200-5-2003 by the Minister for Planning for the operations described in the Feldmast coal project environmental impact statement 1997.

The Feldmast EIS described and assessed open cut, underground and highwall mining activities at Cullen Valley mine. Open cut mining consistent with the Feldmast EIS commenced in May 2000.

Following the identification of additional open cut coal reserves, the Cullen Valley mine open cut extension EIS was lodged in April 2004. This modification to DA 200-5-2003 was granted by the Department of Infrastructure, Planning and Natural Resources on August 19, 2004.

This approves open cut mining activities on the western side of Tyldesley Hill and continued activities under the Feldmast EIS.

Product coal from Cullen Valley mine has historically been supplied under contract to Mt Piper power station.

However, with the failure of the mine to renew a supply contract, the operation was placed on a care and maintenance program in June 2007.

In February 2008, when Coalpac acquired Cullen Valley mine from Lithgow Coal Company, the mine was taken off care and maintenance. The open cut mining operations approved under DA 200-5-2003 re-commenced at that time.