Parsons Sun, November 10, 2010
By Colleen Surridge
Following many months of sampling and analysis, Matrix Environmental Services has begun the process of decontaminating the 900 line at the former Kansas Army Ammunition Plant.
Matrix was hired by the Great Plains Development Authority to oversee the project, pursuant to an environmental services agreement, which the GPDA was awarded by the Army for decontamination of the 900 Area. The original contract was for $4.3 million.
“Ever since June we’ve had eight people out here full time, sampling and getting ready to decontaminate. We started doing decon this last week,” said Peggy Llewellyn, Matrix senior project manager. “What we are doing is explosives decontamination.”
In the remaining 6,116 acres to be transferred from the U.S. Army to the Great Plains Development Authority, there are several old munitions production lines. Matrix will handle the assessment of the production lines and decontamination of the 900 line.
“There were five production lines that are going to be in the Great Plains Development Authority’s footprint. Each production line consisted of roughly 50 buildings,” Llewellyn said. “The first step is assessing the buildings. We collected about 6,000 samples from three of the production lines. We still need to do two.”
In testing, Llewellyn said Matrix is looking for five primary classes of explosives, which at the KSAAP involves about 10 to 20 different chemical compounds.
Some of the explosives are primary compounds used to set the charge in explosives and are extremely sensitive, while others are secondary compounds that provide the “big bangs with lots of power,” but are not as sensitive, she said.
The process of decontamination of buildings is fairly new, being developed following several incidents of explosions at facilities in the 1980s and 1990s. At the Grand Island facility in Nebraska, a worker cutting into a wall with a torch led to massive explosions.
Complete decontamination is necessary, even if the buildings will be razed.
What was discovered in inspecting other facilities, Llewellyn said, was that explosive dust was found to have accumulated in the duct work, piping and inside concrete walls. At one facility she worked on, she said workers opened up one of the concrete block walls that had a crack in it and found explosive dust mounding up inside the wall after years of accumulation. Facilities such as the KSAAP would often hose down the floors in production line buildings, which served their purposes well. However, she said, concrete is absorbent and therefore the floors of some of the buildings contain high amounts of explosives.
“In significant buildings, in terms of where they handled raw explosives, it can get into the cracks and crevices. These buildings were built much more sturdy, with 1 foot thick concrete walls on 1 to 4-foot thick concrete slabs,” she said. “They are very sturdy buildings with blast walls, so if during production, if there was an unintentional detonation it would prevent impact on other areas. They were designed for safety, so taking them down is tricky, because the buildings are so strong.”
“The process we go through when we start decontaminating is to characterize the waste.The floors have explosive residue, old paint chips in the dirt, animal droppings and any number of things. We collect samples of the matter and send it to the lab to determine how to handle it,” Llewellyn said.
“We start with floor sweeping, and send that off for disposal or incineration. We use specialized high volume explosive-proof vacuum cleaners, because we don’t want to set off any sparks or friction,” she said. “After that, we remove the pipes and the lighting in the buildings. Sometimes we have to go in and take out walls. Then we go in with high pressure washers and wash down the buildings using 5 to 20,000 psi (pressure per square inch) to wash them.”
“In smaller buildings we use thermal invection heating with hot gas that reaches temperatures of 400 degrees in the building, which thermally decomposes explosives without detonation.
“With larger buildings, it is not technically feasible to heat them to 400 degrees, so we use the high pressure washers,” Llewellyn said.
The processes used for decontamination interferes with structural stability of the buildings, because under use of high pressure washing, mortar crumbles, or sometimes they have to take out a wall. This means a loss of some of the most structurally sound buildings on the 900 line.
With the limited buildings, where little decontamination is needed, we don’t have to use the same level of treatment, so they can often be saved,” she said. “We can use a low pressure wash, maybe steam cleaning.”
Many of the materials, once decontaminated, can be recycled and used for other projects at the industrial park.
Matrix Environmental’s focus is on explosive cleanup, but when it comes into contact with other environmental issues, such as asbestos within buildings, workers must deal with those contaminants as well.
Llewellyn said such matters will mean Matrix subcontracting with local and area companies as bids complete the review process and are let.
The waste pulled from the buildings will be put into barrels to be hauled off by a waste management broker and another company will be subcontracted to manage asbestos abatement.
“Our goal is also to hire local contractors when we are able to,” she said. “We are putting out waste management bids now,” Llewellyn said.
“It will be spring probably before we are ready to start demo-ing buildings, which we will hire other contractors for,” she said. “From the time we hit the field, it is about an 18-month process. There’s a lot of work to do.”