The invention pertains to the conversion of waste materials derived from gypsum mining and processing, such as existing gypsum stacks, into waste containment or landfill facilities. Advantageously, waste containment facilities and business methods according to the invention enable the creation of a positive revenue stream from previously negative assets such as gypsum stacks. Methods of the invention include the creation of waste containment facilities from existing gypsum stacks, or from the on-site formation of containment facilities from waste gypsum or other waste minerals as they are transported and positioned at a waste site. Waste containment facilities created according to the invention can be used for the short-term, long-term or permanent storage of waste materials such as solid waste, community refuse materials, biomass, industrial waste, phosphate waste, and for composting or otherwise processing materials such as biomass. Containment facilities according to the invention can be lined or unlined, open or capped, depending upon the nature of the material to be resident in the containment facility and relevant governmental regulations. The invention also provides for drainage and recovery systems, monitoring, controlling and communication means, pumps and valving means, and any other means known in the waste containment facility field. The invention comprehends also the storage and processing of materials such as biomass within a containment facility according to the invention and the sale of usable products derived from that processing.