Tailings storage facilities are typically designed with retaining dikes built using three different construction techniques: the upstream, downstream and centerline methods. The upstream-raised method is the most common due to its simplicity and cost-effectiveness. However, the stability of such impoundments is sometimes a concern, as these have been prone to failures, especially in high seismicity regions. The use of waste rock inclusions (WRI) was proposed to improve the stability of tailings impoundments with upstream-raised dikes. This method of co-disposal consists of placing rows of waste rock within the impoundment prior to each step of raising the tailings and dikes. Recent studies on the effects of waste rock inclusions on the stability of tailings impoundments have indicated that this co-disposal method may improve the geotechnical behavior of the impoundments under both static and dynamic conditions. This project aims at providing design guidelines for WRI derived based on numerical analysis, for a wide range of seismic hazard, impoundment geometry, and tailings density.