Turner, J.V., and Townley, L.R. (1993), Groundwater - lake water interactions near Lake Jasper, D'Entrecasteaux National Park, Western Australia. First half-yearly report to Cable Sands (WA) Pty Ltd for the period May to October 1993. CSIRO Division of Water Resources, Consultancy Report 93/39, 59pp., December 1993. [Confidential]

Work commenced on the project in May 1993 and the two-year project is scheduled for completion in April 1995. Fortunately, a late start to winter rainfall permitted preliminary drilling and piezometer installation to be carried out in May. Preliminary results from these piezometers have proven to be invaluable in interpreting the surface water - groundwater interaction.

The purpose of this six-monthly progress report is to present a summary of work currently in progress. The report presents preliminary interpretations on the conceptual hydrogeology of Lake Jasper and links these to field observations. A description of the way in which hydrogeochemistry and stable isotopes will be used to determine the water balance of Lake Jasper and hence its interaction with groundwater is presented. Detailed descriptions of the field program and preliminary results are given, as are a description and summary of a regional groundwater model of the Lake Jasper area.