Staged Emergency Spillway Development – Design Considerations

Staged Emergency Spillway Development – Design Considerations

Author: K.L Ainsley, B. Otis, E. Chong
Conference: 87th Annual Meeting of the International Commission on Large Dams
Date: June 9-14, 2019

ABSTRACT
Under most circumstances, spillway structures are required for the safe operation of a dam, helping to control the release of excess water within the impoundment to a location downstream. Where spillway facilities exist, it is essential that they are capable of operating throughout their design life and within prescribed regulatory requirements. This condition becomes more challenging when an emergency spillway needs to be incorporated into the design of a tailings storage facility (TSF). TSFs are typically designed for the final arrangement anticipated at mine closure. In order to reduce mine operating capital costs, TSFs are often constructed in staged lifts as dictated by tailings production estimates. Consideration for the spillway is required with each lift. Several factors influence the dam and spillway geometry including supernatant pond volumes, climatic conditions, tailings production rates, volumetrics of the impoundment, spillway location, geotechnical considerations, mine closure criteria. This paper will explore the key considerations for the development of a TSF emergency spillway. The spillway development at the Phu Kham Copper-Gold Operation (operated by Phu Bia Mining Limited) located in the Lao People’s Democratic Republic will be used to illustrate these considerations.

 

Download the full technical paper.

Download

Recent Insights

November 2023
Earthquake-induced Deformation Analysis of a TSF Undergoing Tailings Reprocessing
November 2023
Case Study: Approach to Determining the Risk Mitigation Priority of a Historic TSF in North America
October 2023
The Role of Sensitivity Analysis in Selecting Dam Breach Parameters
September 2023
Transición energética para gerentes de mina
August 2023
Interview: Guillermo Barreda, Gerente General, Knight Piésold Perú
July 2023
Selection of Soil Shear Strength Parameters Based on Integrated In Situ Tests, Lab Tests and Numerical Calibration Approach
June 2023
Leveraging Knowledge and Experience of a Well-Formed Independent Tailings Review Board to Enhance Tailings Facility Safety
May 2023
Is the Implementation of Dry Stacking for Tailings Storage Increasing? A Southern African Perspective
February 2023
Canadian Consulting Engineer's Lifetime Achievement Awards: Jeremy Haile
February 2023
Geotechnical Characterization of Collapsible Salty Sands Subjected to Monotonic and Cyclic Loadings – A Case Study for Areas with High Seismicity
November 2022
Application of the 3D Limit Equilibrium Method in Tailings Dam Breach Analysis
November 2022
Evaluation of Tailings Behaviour for Dam Breach Assessments
November 2022
Tailings Improvement by Stress-Densification from Waste Rock Capping
November 2022
Transforming Tailings Management Systems toward Alignment with the GISTM: A Case History
October 2022
Managing Excessive Pit Wall Deformation of Weak Rock Mass
October 2022
State-of-the-art Method for Estimating Long-term Hydroclimatic Conditions for Tailing Dam Water Management and Dam Safety Planning
August 2022
Observed Subsidence Progression at New Afton Mine in Response to Lift 1 Mining
June 2022
Hydrometric Monitoring and Effluent Discharge Mixing in Challenging Natural Conditions
May 2022
Inundation Modelling of Non-Newtonian Tailings Dam Breach Outflows
May 2022
Video: Tailings Management Compliancy Picks Up Momentum