A berm to increase capacity of an existing landfill comprises a reinforced portion and backfill material. The landfill comprises a waste-receiving recess having a surface and an outer perimeter, an edge surface peripherally adjacent at least a portion of the outer perimeter, and an existing accumulation of waste within the recess having a collective top surface. The reinforced portion has opposing inner and outer surfaces and comprises structural fill material and a plurality of reinforcing members disposed therein. The backfill material has an inner surface adjacent the inner surface of the reinforced portion. The backfill material comprises contaminated fill material and is at least partially encapsulated by an impermeable membrane. At least a portion of the berm sits on at least a portion of the edge surface of the landfill. Portions of the berm are substantially parallel to corresponding portions of the outer perimeter.