In 1985, the United States Congress passed legislation requiring the disposal of the stockpile chemical agents and munitions consisting of over 3 million chemical weapons, adding up to 31,000 tons of chemical weapons needing to be disposed of. This was ordered because a timely and safe disposal of chemical weapons is far safer than chemical weapon storage. Between the years of 1982 and 1992, the United States army reported approximately 1,500 leaking chemical weapons munitions, and in 1993 a 100-gallon chemical spill was reported at the Tooele Army Depot in Utah consisting of mustard agents. When chemical weapons are leaked or spilled into the ground, an insidious process follows where the condition of the agent is unknown. This occurs because the process of chemical agents degrading in soil is a complex process that is affected by many factors such as temperature, acidity, alkalinity, meteorological conditions, and the types of organisms present in the soil. This complexity causes persistent agents such as sulfur mustards to be harmful for decades.