The licensee's 1981 coal search programme at Lake Phillipson had the following objectives: - delineation of the total extent of the coal measures; - resolution of seam stratigraphy and correlation of seams between the Main and West Areas; - delineation of subcrop and 'lip' geometry; - recovery of cores to supplement the analytical database; and - selection of the most promising mining areas in terms of stripping ratio and in situ quality. 69 drill holes were completed totalling 8503 metres, of which 857.7 metres were cored, with the remainder completed via open hole blade bit drilling. 10 of the drillholes were located in the Main Area sub-basin and 41 in the West Area sub-basin, with another 2 exploratory non-cored holes drilled in the Robin's Rise area located approximately 9 km to the east of the Main Area basin axis. The latter drilling was carried out to test a trough-like seismically defined structure, trending roughly east-west, with geological features akin to the Main and West areas. The presence of some Permian coal in this structure was confirmed. 267 coal core samples were collected for routine coal quality testing by Amdel. Separate beneficiation studies were performed to determine whether high sodium levels in the coal could be reduced by washing with water. This proved to be the case. The inferred coal resource (as opposed to reserves) for the Lake Phillipson deposits is clearly huge (in excess of 5 billion tonnes in an open cut situation). A problem with using the coal for steam-raising purposes remains its high sodium-in-ash content, which makes for boiler furnace slagging and fouling. A mining feasibility study was also undertaken, and it shows that development costs for an electrically equipped open-pit mining operation, extracting the seams at the southern end of the West Basin and producing either 2, 5 or 10 million tonnes per year of sized and washed coal @ 30% moisture, are $444 million, $723 million, and $1272 million respectively. The modelled annual production levels have been selected according to the envisaged supply build-up schedule for a 2000 MW power station. On this basis the minimum Free-On-Railhead coal price, allowing for a 15% discounted cash flow, is $44.39/tonne. These extraction costs, together with the high required coal price, clearly demonstrate that the coal resource is currently not economic to mine.