One of the more important aspects of slope design is comparing a new slope design with any previous experience or performance of slopes in similar materials and environment. However, in environments such as the Moatize Coal Basin, Tete Provence, Mozambique, where no large scale open pit mining has occurred in the past, previous experience is non-existent. This paper focuses on the design of two large open pits in the Moatize Coal Basin and techniques that were employed to counteract the lack of previous experience or performance guidelines. Greater reliance is placed on the creation of an accurate geotechnical model of the mining environment.