Oral Presentation NCGRT/IAH Australasian Groundwater Conference 2019

The use of proxy data for hydrogeological site characterisation (506)

Todd Hamilton 1
  1. Klohn Crippen Berger, St Lucia, QLD, Australia

The hydrogeological characterisation of a mineral deposit is often undertaken under significant economic constraints.  While the hydrogeological regime is every bit as, or more, complicated than the mineral distribution and characteristics, the resources available to characterise this regime are often meagre by comparison.  Given the typically high spatial variability of hydraulic parameters such as hydraulic conductivity, specific yield or various hydrochemical parameters, the development of a conceptual and numerical hydrogeological models to an appropriate level of confidence can be a significant challenge. 

There are, however, often opportunities to collect and utilise the typical geological, geophysical, geotechnical, metallurgical and other data which are useful proxies for hydraulic parameters.  In most cases, these data already exist or may be collected at a relatively low cost.  These can be obtained from an exploration stage onwards and can be used to improve the hydrogeological understanding of the deposit, focus subsequent targeted hydrogeological investigations and reduce the cost of subsequent groundwater exploration or mine dewatering programs. 

This paper examines the opportunities to collect and analyse data which may have statistically significant correlations with hydraulic parameters and may be used to extend and improve the hydrogeological characterisation at a moderate cost.  Those data sources include geophysical data, basic drilling data, geotechnical parameters, structural geological characterisation, alteration logging and others.  Case histories are described which document the development of statistically significant relationships between these data sources and site hydraulic parameters, which were then used to provide greater confidence to the site hydrogeological model.