The objective of this project is to explore the problem of dessication cracking of clay liners used to cap hazardous waste landfills. The project will quantify the soil stresses which accompany cracking, the resulting crack geometry and its time variation, and the mechanics of flow through the cracked soil. The findings will be incorporated in an existing numerical model of flow through clay liners. The developments from this project are expected to significantly expand previous research in the flow through clay liners, and provide a base for even more sophisticated studies of the problem. The research is expected to impact landfill designers, regulatory agencies, contaminant transport modeling, and others involved in infiltration/percolation studies or the design of containment systems.