Abstract: A waste disposing ground or facility includes a space in the form of a cavity for receiving waste therein. A planar structure covers the entire overall upper opening of the cavity. The planar structure is constructed in advance of starting disposal of waste into the cavity. Arranged on the lower surface of the planar structure is a system for spraying water on the waste. Disposed at the bottom of the cavity is a system for discharging air. Since air can be discharged from the bottom of the cavity that is closed by the planar structure, the atmosphere surrounding the waste in the cavity can be changed from an anaerobic state to an aerobic state. Since water is supplied on the waste, decomposition of organic substances which decompose under aerobic conditions can be promoted. If air is not discharged from the air discharging system, the waste is placed in an anaerobic condition, and decomposition of the organic substances which decompose under such conditions can be promoted.