Special to the Register

The design of a pilot plant that will destroy chemical weapons at the Blue Grass Army Depot includes all the steps required for safe and effective destruction of the weapons, but these steps have yet to be integrated and tested, according to a new report from the National Academies' National Research Council.

Some operational issues also need to be addressed, stated the committee that wrote the report. And to save time and money, large amounts of wastes that are uncontaminated by chemical agents should be disposed of off-site at qualified waste-disposal facilities.

“With the current design at Blue Grass, we anticipate that the chemical agents can be safely and effectively destroyed,” said Robert A. Beaudet, committee chair and professor of chemistry, University of Southern California, Los Angeles. “But, the contractor still must integrate the individual treatment steps into a total process. Also, the methods designed to treat secondary wastes are immature and untested, for the most part.”

The U.S. Army asked the Bechtel Parsons Blue Grass team - a joint venture of Bechtel National Inc. and Parsons Infrastructure and Technology Group - to devise a plan for a pilot plant capable of safely and effectively destroying the stored chemical munitions.

The design plan was submitted to the Army in July 2004, and operations at the plant are expected to start in 2008. The chemical munitions stored at the Blue Grass Army Depot will be destroyed by “neutralization” - a process using a sodium hydroxide solution - followed by oxidation in water under very high temperature and pressure.

Individual plant operations have never been deployed together as a single, integrated process, increasing the likelihood of unexpected complications during the plant's start-up, the committee said.

The Army and its contracting team should be prepared to modify the operations as design, testing and construction proceed, the committee added, and assumptions about the availability of first-of-its-kind equipment should be reviewed given the possibility of failures.

Some of the techniques that will be used to destroy the rockets containing the chemical agents must be improved, the report says. For example, the machine that will be used to initially cut each rocket should be altered to avoid the possibility of igniting the propellant inside.

After the chemical agents and various rocket segments are treated with neutralizing solutions, the material that remains, called hydrolysate, is treated by oxygen in “supercritical” water - water at temperatures greater than 705 degrees Fahrenheit and pressures about 220 times the atmospheric pressure - and thereby transformed into an environmentally benign substance.

But, this process is very corrosive to the walls of the supercritical water reactors into which the hydrolysate is placed and can cause solid materials to form and plug the reactors. Although methods have been developed to mitigate these problems, additional testing is needed to confirm that these remedies are adequate, the report says.

The supercritical water reactors that the Army plans to use have not been tested on contaminated secondary wastes, which include storage and packing materials, pallets and the protective suits workers wear when handling the rockets.

The large quantities of uncontaminated secondary wastes that have never been in contact with the chemical agent should be sent off-site for destruction by qualified waste-disposal facilities, the committee said.

The Army should consider treating contaminated secondary wastes with alternative approaches, including one that decontaminates materials by heating them to 1,000 degrees Fahrenheit, the committee added.

While working with the Bechtel Parsons Blue Grass team on the design of the pilot plant, the Army has provided the local community with up-to-date information on the plant and the techniques that will be used, the committee noted. The Army and its contractor should continue to pursue and support public involvement and make the safety of workers and the public a foremost consideration, the report says.

The Bechtel Parsons Blue Grass team also should consider inviting input from the general public on risks associated with operations at the plant.

The study was sponsored by the U.S. Department of the Army. The National Research Council is the principal operating arm of the National Academy of Sciences and the National Academy of Engineering. It is a private, nonprofit institution that provides science and technology advice under a congressional charter.