Dowling, J, Beale, G, Haas, P, Kaya, B, Mak, S, Tejada, LC, Kramer, K, Johnson, J, Zea, RE & Palmer, C 2020, 'Development of an integrated workflow for pit slope pore pressure reconciliation', in PM Dight (ed.), Slope Stability 2020: Proceedings of the 2020 International Symposium on Slope Stability in Open Pit Mining and Civil Engineering, Australian Centre for Geomechanics, Perth, pp. 1267-1280, https://doi.org/10.36487/ACG_repo/2025_86
(https://papers.acg.uwa.edu.au/p/2025_86_Dowling/)
Abstract: Mine plan implementation for the Western Copper open pit at Morenci in Arizona requires an intense program of bedrock dewatering production pumping to support sinking of the pit and reduce impacts of groundwater on day-to-day mining. In addition, the pit slope design contains specific groundwater pressure targets which are generated for annualised increments of the mine plan by the slope design team. The mine dewatering program is therefore also utilised to accomplish depressurisation for slope management purposes. As part of the slope depressurisation process at Morenci an innovative workflow was developed to reconcile observed pit slope pore pressures against geotechnical targets and predicted depressurisation results. The integrated workflow has provided a valuable pit slope pore pressure management tool to the program. This paper presents a review of the integrated workflow.

Keywords: dewatering, depressurisation, piezometers, workflow, integration, targets