Mount Morgan Mine Site
Mount Morgan is a historic mine site located next to the township of Mount Morgan, near Rockhampton, Queensland. Between 1882 and 1981, gold and copper were mined using underground and open cut techniques. The mine closed in 1990 after retreatment of tailings, which were placed into the open cut. In 1993, the State of Queensland accepted environmental liability for the site with technical oversight by the Department of Mines and Energy (now NRME). The site is characterized by problems associated with acid rock drainage, which has impacted the site and a nearby river (Dee River). The NRME undertook a series of studies to identify key contaminant sources, understand water movement on site and develop a range of rehabilitation scenarios for the site. See also the NRME website for more details.
RGC, in association with O’Kane Consultants Inc and Fawcett Mine Rehabilitation Services, was retained by NRME to perform a groundwater assessment of the site to characterize the local groundwater system. RGC designed and supervised a detailed field investigation, which was comprised of drilling, monitoring bore installation, hydraulic testing and water quality sampling.
RGC used the results of the field investigation to construct a 3D groundwater model for the site. The model was used to develop an understanding of the current groundwater conditions on site, and to estimate the contribution of seepage from each of the various mine waste units to the groundwater system. The model was also used to evaluate the effectiveness of the seepage interception system (SIS) currently in place and estimate the amount of contaminated water bypassing the SIS and entering the Dee River. Furthermore, the model was used to determine the influence of various closure scenarios for the open cut on the groundwater system. In conjunction with the groundwater model, a 3D digital terrain model was developed for the site to estimate the volume of the various mine waste units.
As a subcontractor to Connell Wagner, RGC was also retained to evaluate the various remedial options for historic dams in Dee River. The study included an impact assessment of various rehabilitation options on the local groundwater flow regime, on the seepage interception system and on contaminant loading in the river.
Since the original field investigation and modeling work, RGC has performed annual groundwater monitoring reviews of the site and continues to assist in routine monitoring.
- Groundwater review and assessment
- Design and supervision of groundwater field program (drilling, installation, hydraulic testing)
- Development & calibration of a 3D groundwater flow model (MODFLOW)
- Development of a 3D digital terrain model
- Impact assessment and closure strategies
- Assistance in routine monitoring (Reporting, QA/QC)
- Wels, C., Findlater, L., and McCombe, C. (2006): Assessment of groundwater impacts at the historic Mount Morgan Mine Site, Queensland, Australia. In proceedings of the 6th International Conference on Acid Rock Drainage, St Louis, Missouri, USA, March 26-30, 2006.
- Wels, C., Findlater, L., Shaw, S. and Laurencont, T. (2004): “Mt Morgan Mine – A Case Study of ARD Impacted Groundwater”. In proceedings of Mine Water 2004 – Process, Policy and Progress Newcastle upon Tyne, United Kingdom 20-24th September 2004, pp 235-245.
Queensland Department of Natural Resources, Mines and Energy (NRM&E)