Cooking up a solution

This story was published Sun, May 6, 2001

By Wendy Culverwell
Herald staff writer

In a huge warehouse in the Big Pasco Industrial Park, a high-tech system designed to neutralize the Army's stockpile of aging chemical weapons shares space with a turkey cooker.

Engineers designed the former as an alternative to incineration for mustard and other chemical weapons agents. They use the turkey cooker to cook up batches of hard candy, which serves as a stand-in for time-hardened chemicals during testing.

Parsons Infrastructure and Technology, a subsidiary of the California engineering giant Parsons, is preparing to send the Army a pilot-scale test model of a system it developed to clean chemical agents out of old mortar shells using pressurized water and superheated steam. The water-based approach can be used in place of the incineration techniques used at places such as the Umatilla Chemical Depot.

Parsons started work on the "wash out" system after Congress established the Assembled Chemical Weapons Assessment Program (ACWA) in 1996 to find ways to destroy chemical weapons that didn't involve the controversial incineration approach. Under ACWA, the Department of Defense was charged with identifying at least two alternatives that didn't involve incineration.

Parsons also developed the incinerator technology.

"We feel incineration is safe, but if they want to look at alternatives, then we will," said Jim Osterloh, manager of the Pasco shop where the two-story wash-out system was developed.

Osterloh started working on the ACWA project three years ago at Parsons' Richland office. The operation branched off to the Port of Pasco in November when it needed more space.

He chose the cavernous, 20,000-square-foot bay in Big Pasco's Building 5 for one simple reason. "It's big," he said, adding that he expects to take over even more space as additional business flows in. The operation has about 30 engineers and crafts people and will grow to 80 on the next project, he said.

Water-based processing is more than an alternative to incineration. It resolves a thorny processing problem posed by chemicals that have changed form after spending so many years in metal mortar containers.

Before chemicals can be destroyed, they have to be drained from the shells where they have sat undisturbed since the 1950s. In their original form, the chemicals were liquid and could easily be pumped. The trouble is, the chemicals have changed over the decades, thickening to something comparable to hard candy in the case of mustard. Mortar shells can pass through the incinerator if 10 percent or less of the chemical content remains. Unfortunately, as the military has found, as much as 80 percent of the hardened residue often remains, which seriously slows down the incineration process.

The Parsons approach tackles the crusty chemicals with high pressure water. First, a clamp grabs the mortar shell and the bottom is cut off - like a can of beans in a can opener, as one visiting metallurgist observed.

Still clamped, the open-bottomed mortar hangs over five nozzles that shoot 10,000 pounds per square inch of water at the insides to flush out the goop.

The chemical-contaminated water is treated and remains in the closed loop system. The metal mortar shell enters a steam-heated chamber where any remaining contaminants are vaporized. The shells enter through an airlock. Air is monitored for vapor contamination and treated through a series of filters before being released.

Once they've been treated, the government can release control of the mortar shells.

Karyn Jones, a member of the Hermiston group GASP, has spent 11 years fighting the Army's plan to incinerate chemicals at Umatilla. An active supporter of the ACWA process, she said she has high hopes for Parsons' washout approach, which still must be tested in Utah.

To test the approach, the developers filled dummy shells with hard candy they cooked up in a turkey pot over a propane burner. The recipe, Osterloh said, came from his mother: Water, sugar and Karo syrup cooked to the hard-crack stage. It is poured into the mortar and allowed to harden.

The candy is a good test because it's actually a bit harder than mustard, which makes it more difficult to flush out. Plus, it tastes good, Osterloh joked.

The other challenge came when engineers discovered the dummy mortar shells weren't as tough as the real ones. The cutter sliced the bottoms off the dummies, but broke constantly when tested on the real thing.

The two-story version constructed in Big Pasco will be broken down this week so it can be trucked to the Army's Chemical Agent Munitions Disposal System facility near Tooele, Utah.

 

Copyright 2002 Tri-City Herald. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.