How Subduction Works

1. At a subduction trench, the STV is buried under the surface of the sediment. The STV will settle to the bedrock surface of the oceanic crust, alleviating the need for more than a 50-foot deep hole.

2. The STV is slowly being pulled into the earth's mantle. Plutonium, the most dangerous of the radioactive waste, has decayed sufficiently to be harmless to the environment. Failure of the system after this point will not expose the environment to radioactive danger.

3. This location marks the beginning of the interplate earthquake zone. The STV is designed to survive subduction earthquakes via design, shape and materials used in the concept. The shape prevents rock from snagging the STV; the material is as strong as the surrounding rock; the design causes pressure exerted on it externally to cause an equal rise in pressure in the interior without STV seal failure.

4. At this point, the STV has heated to about 350-400 degrees Celsius. This is the center of the subduction fault.

5. Now the STV is well below the continental crust and in the area of serpentized mantle, which is created by the flow of material entering the mantle from the surface.

6. Below about 200 miles in depth, the heat has risen to about 1100 degrees Celsius. At this temperature and depth, the stainless steel begins to soften. The beginning of the failure process of the STV causes the pressure-compensating design to become non-functional. However, the waste may not be released in spite of distortion to the steel.

7. At about 300 miles in depth, the steel finally yields to the increasing temperatures and melts, releasing all waste. Waste plutonium and uranium, being many times heavier than iron and the surrounding magma, slowly sinks through the upper and lower mantles. As it reaches the bottom of the lower mantle, it encounters the outer core, composed of liquid iron, which flows like water at temperatures of several thousand degrees. The spent fuel will go through this area quite easily and come to rest on the outer surface of the inner core.

8. Some lighter elements, such as the fuel rod tubes, may not sink with the spent fuel but slowly rise and stick to the bottom of the continental crust. Depending upon insertion location, these lighter elements could, in millions of years, be ejected out of a volcano. At that time, these materials would be harmless due to radioactive decay.

The path of the STV's descent from the subduction zone to the inner core is illustrated on the following page:

How It Works
*Patent Pending