Asphalt rehabilitation projects produce about 100 million tons of recycled asphalt pavement (RAP) per year from millings, presenting a major solid waste concern. Literature indicates that RAP has a structural value as a pavement layer. However, limited research exists to quantify its structural capacity with fundamental engineering properties, especially for high RAP contents. Properties such as the resilient modulus (MR) of unbound layers are needed in the mechanistic-empirical pavement design guide. This paper investigates the behaviour of base layer mixture containing RAP at different quantities using resilient modulus (MR) from laboratory testing. RAP from millings was blended in varied quantities with local aggregates. Densities also varied among test specimens. Resilient modulus tests showed that as RAP content increased, R increased. Results also showed a strong positive correlation between MR and density. Conclusions indicate RAP has a potential to be used in high percentages in pavement base layer applications. Doing so may help alleviate a growing environmental problem while providing a strong pavement foundation.