This technical report details the methods and results the drilling programs of the Upper Burdekin Groundwater Project conducted as part of Exploring for the Future (EFTF)—an eight year, $225 million Australian Government funded geoscience data and information acquisition program focused on better understanding the potential mineral, energy and groundwater resources across Australia. This report was written by Queensland Government collaborators in the Department of Environment and Science, and is published here as supplied to Geoscience Australia at the conclusion of the project. The drilling program itself was conducted by the Department of Environment and Science as part of the Upper Burdekin Groundwater Project. A total of 17 holes were drilled in 2017-18 at 13 sites with a total combined depth of 943.2 metres. These comprise selected locations across both the Nulla Basalt Province and McBride Basalt Province. A network of 15 monitoring bores were constructed with two test holes backfilled and decommissioned.

<div>The Kati Thanda – Lake Eyre Basin (KT–LEB) covers about 1.2 million square kilometres of outback Australia. Although the basin is sparsely populated and relatively undeveloped it hosts nationally significant environmental and cultural heritage, including unique desert rivers, sweeping arid landscapes, and clusters of major artesian springs. The basin experiences climatic extremes that intermittently cycle between prolonged droughts and massive inland floods, with groundwater resources playing a critical role in supporting the many communities, industries, ecological systems, and thriving First Nations culture of the KT–LEB.</div><div><br></div><div>As part of Geoscience Australia’s National Groundwater Systems Project (in the Exploring for the Future Program) this report brings together contemporary data and information relevant to understanding the regional geology, hydrogeology and groundwater systems of Cenozoic rocks and sediments of the KT–LEB. This work represents the first whole-of-basin assessment into these vitally important shallow groundwater resources, which have previously received far less scientific attention than the deeper groundwater systems of the underlying Eromanga Basin (part of the Great Artesian Basin). The new knowledge and insights about the geology and hydrogeology of the basin generated by this study will benefit the many users of groundwater within the region and will help to improve sustainable management and use of groundwater resources across the KT–LEB.</div><div><br></div>

This data release contains accurate positional data for groundwater boreholes in terms of horizontal location as well as elevation of the top of casing protectors. Twenty-four boreholes located in the Nulla and McBride basalt provinces have had DGPS survey results compiled and are presented. Using 95% confidence intervals, the horizontal uncertainties are less than 1.2m and vertical uncertainties less than 0.9m. These results are a substantial improvement, particularly on the uncertainty of elevations, and as such allow water levels need to be compared between bores on a comparable datum, to enable a regional hydrogeological understanding. Quantifying the uncertainties in elevation data adds robustness to the analysis of water levels across the region rather than detracting from it.