The Integra Underground Project Area is predominantly covered by shallow hillslope-based colluvium, with alluvial based sedimentary deposits in the valley floors. These are in turn sequentially underlain by coal measures of the Vane Subgroup, Archerfield Sandstone and Jerrys Plains Subgroup of the Whittingham Coal Measures. The sequence contains interlayered sandstone, conglomerate, mudstone, siltstone and coal.

Underground mining operations are approved at a maximum extraction rate of 4.5 million tonnes per annum (Mtpa) of run-of-mine (ROM) coal until 31 December 2035 under PA 08_0101. This approval allows longwall mining of the Hebden, Barrett and Middle Liddell seams to produce high quality, semi-hard coking coal for export.

Integra Underground was placed under care and maintenance in May 2014, during this time environmental management of the site was maintained under a Care and Maintenance Environmental Management System. Operations recommenced in 2017, with development resuming in February 2017 and longwall extraction resuming in May 2017. The reporting period (2018) is therefore the first full year of mining operations since being placed under care and maintenance.

Integra Underground completed secondary extraction of Longwall 13 in July 2018 and commenced secondary extraction of Longwall 14 in early September 2018. Development of first workings for Longwalls 15 and 16 continued in 2018, with secondary extraction of Longwall 15 due to commence in late July 2019.

All ROM coal was stockpiled by Integra Underground before being hauled by Bloomfield operations
along their internal haul roads to Rix’s Creek North (owned by Bloomfield) CHPP for processing.