Abstract: A composition particularly useful in solidifying liquid wastes for disposal in landfills, including, for example, liquid industrial wastes. The preferred embodiment of the present invention contemplates a composition primarily composed of bauxite tailings that remain after alumina extraction, also known as "red mud". The tailings are dewatered, dried to a low moisture content, sized to an optimal particulate size, and then applied to the liquid waste. The addition of a small amount of pozzolanic material can improve the handling and solidification characteristics of the composition under certain situations, and is provided in an alternative composition.

Abstract: 1. In a pressure responsive mine having a casing and an arming and firing rcuit therein, a pressure responsive device mounted in the casing and exposed to the pressure of the sea water, a second pressure responsive device mounted in the casing, a fluid connection between the first and second pressure responsive devices, a third pressure responsive device mounted in the casing, a restricted fluid pressure responsive connection between the second and third pressure responsive devices, and a circuit making and breaking device positioned in the restricted connection between the second and third pressure responsive devices and connected in the arming and firing circuit.