Sanergy employees empty the toilets each day, taking an air-tight container of waste to a Sanergy processing facility where it is converted to biogas and fertilizer that Sanergy plans to sell to commercial and small farmers.

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Used fuel that has been cooled in a spent fuel pool for at least five years can be put into a container called a cask and surrounded with inert gas, providing leak-tight containment, according to the U.S. Nuclear Regulatory Commission.

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