- Successful pilot program to mitigate subsidence risk
- Our newly developed design approach injected high-mobility grout beneath a densely developed residential area
- Strategically located discharge wells help to control artesian flow
- Project featured in Mining Engineering Magazine: Subsidence Mitigation in Artesian Conditions
Brierley Associates developed a unique approach to mitigate surface subsidence risk caused by old non-working coal extraction sites. These sites are inundated with water under high artesian conditions. Hydraulic communication between mine water and groundwater aquifers was a concern. To obtain real field data, a pilot program was developed to demonstrate the viability of a newly developed design approach and feasibility of injecting high-mobility grout beneath a densely developed residential area with minimal impact on the groundwater regime.
Throughout this program, Brierley was successful in adopting means and methods to control artesian flow by installing strategically located discharge wells. This allowed maintaining optimal equilibrium between induced pressure increments developed by grout injection and the pre-existing pressure regimes within the affected aquifers. In addition, surveying of ground monitoring points during the pilot program documented the absence of ground heave or settlement as a result of the grouting work.