By the time the brick works were finally closed, the land was a patchwork of flooded pits, hollows and low mounds with the remains of various brick kilns and other buildings. The Corporation decided to make use of the pits by pumping out the water and using them for waste disposal, as the York Corporation Civic Amenity Tip and Landfill Site. Over the next twenty years the brick pits were filled with domestic refuse and industrial waste.
Industrial waste disposal at St Nicholas Tip was storing up problems for the future, with materials including asbestos and heavy metals. More immediate problems were created by domestic refuse. Rotting refuse smelt strongly in warm weather and was a breeding ground for flies. In 1971 local residents petitioned the council to complain that the tip was infested with rats and should be closed down. In 1974 the tip was finally closed.
Natural regeneration and colonisation gradually brought new life to the Fields. Local people began to notice the wide range of plants thriving among the refuse and the songbirds nesting in the thickets of bramble and elder bushes.