A couple in the US state of Iowa is suing DuPont in a district court over a fire in a corn stover for a new cellulosic ethanol plant in March of this year.

Burdell and Barbara Clark allege that the chemical giant's Danisco division acted "recklessly and carelessly" in storing the "highly combustible" stover in a field across from their home. They are asking that the bales be removed and also seeking compensation for damage to their home and property.

DuPont Danisco is building a $225 million plant that will use stover - corn leaves, stalks and other agricultural residue to manufacture the ethanol. The company said it will require 700,000 bales/year as feedstock and will collect them within a 50-mile radius.

The 30 million gallon/year plant will use a new process developed by Poet-DSM, which is claimed to be significantly more environmentally friendly than the traditional route based on gasoline.

County emergency management officials told local media that the DuPont business has had five fires at stover storage agencies in three years, none of which up to now had caused any damage. The blaze in March was attributed to a lightning strike.

Due to the intensity of the heat, firefighters are said to be unable to get close enough to blazing bales to extinguish the flames.

DuPont said it has worked together with Iowa State University to build a "safe and sustainable stover management system."  It said also that it is conductive "extensive investigations to determine if additional safeguards are required."