Waste and byproducts from the plant, which manufactures nearly all of the propellants used in ammunition for the U.S. Army, are too volatile to be dumped in a hazardous materials landfill. In some cases, floor sweepings can contain tiny bits of metal, which could cause a spark or explosion inside a traditional incinerator.
Outdoor burning of those materials is governed by a DEQ permit that expired in 2015 but remains in effect until a new one is approved.
The current permit allows the arsenal to burn up to 8,000 pounds per day of propellant waste — referred to as dry burns because the material needs no accelerants to catch fire — every day of the year.
Under the new permit, dry burns would be limited to 5,600 pounds per day, for no more than 183 days a year. So-called wet burns, which require diesel fuel and kindling such as cardboard, would be allowed to remain at the current maximum: 2,000 pounds a day for 365 days a year.
Dry burns, which account for most of the activity at the burning grounds, would be restricted to just over 1 million pounds of propellants per year, a 51% reduction from the current figure.
The weight limits set by the existing permit have not been met in recent years, Powell said, noting that in 2020 the arsenal treated just 5% of what was allowed.
The fires produce what DEQ calls “constituents of concern”: perchlorate, chlorate, chlorite, chloride, carbon tetrachloride, chloroform, methylene chloride, chloromethane and methane.