Rossco-1 spuded on 14 December 2005 and reached total depth of 3050 m within the Tirrawarra Formation on 29 December 2005. Independent interpretation of wire-line logs and pressure data confirmed the likely presence of several combined gas bearing zones and, following a mechanical failure during DST #1, it was decided that the well be cased and suspended for testing during a future CHPT. Rossco-1 was operated by Great Artesian and 25% funded by Traditional Oil Pty Ltd (a wholly owned subsidiary of Bandanna Energy Limited), which will retain a 12.5% interest in any subsequent production licence.
CHPT commenced on 7 June 2006 with a program to test five sandstone intervals. The program entailed testing of five sandstone intervals interpreted as being hydrocarbon bearing on the basis of wireline geological data and engineering data at the time of drilling. Four of these sandstones lie within the Patchawarra Formation, and one within the overlying Toolachee Formation.
Testing had to be abandoned due to wet weather and will resume in conjunction with testing programs for adjacent offset wells.