Digging deep to clear hidden refuge danger

Explosives: Environmental engineers use high technology to probe beneath the surface of Patuxent Research Refuge for live ordnance.

January 24, 2003|By Rona Kobell | Rona Kobell,SUN STAFF

For more than a decade, thousands of hunters and hikers have flocked to the Patuxent Research Refuge's North Tract near Laurel in search of the white-tailed deer, warblers and bald eagles that call the 8,100-acre preserve home.

Some of those visitors have found decidedly unnatural creations, too: grenades, mortar shells and rockets that date to when the refuge was a munitions training ground for war-bound soldiers at Fort Meade.

This month, the Army and the Department of the Interior began overseeing the laborious process of finding and clearing ordnance from the North Tract's most-used areas.

Using a sophisticated magnetometer attached to an all-terrain vehicle with a global-positioning system, environmental engineers with New Jersey-based Foster Wheeler Corp. are working to identify potential explosives in about 300 acres in a way that protects habitats and promotes safety.

"Anything that's down there that needs to be removed, we can remove," said Timothy Reese, project manager for Foster Wheeler, who expects the removal process to begin in March.

The most recent cleanup occurs 12 years after Congress transferred the North Tract from the Army to the Department of the Interior, a move that tripled the wildlife refuge's size and preserved a large tract of forestland in fast-developing western Anne Arundel County.

"The transition of the property happened quickly in 1991, and we had no assumptions of what the land use would be," said Kimberly Gross, Fort Meade's coordinator for the Base Realignment and Closure Act at the U.S. Army Corps of Engineers in Baltimore.

"We did a surface sweep over the entire area way back, but now we're focusing on the land-use data so we can go a little deeper."

Using a device called a Towed Array that looks like a gondola attached to farm equipment, engineers are driving five magnetometers across the tract to log the magnetic features of the earth and transfer the data to a laptop computer.

From a computer in his trailer, geophysicist Bill Everham can view all the metal "hits" in bright pink.

When he finishes the land survey at the end of next month, he will send the data to a colleague in Colorado, who will determine which of the hits are likely to be ordnance.

Then, Foster Wheeler's engineers will go back into the refuge and plant flags to mark the possible explosives.

Foster Wheeler's $2 million contract with the Corps of Engineers also includes clearing 22 acres of scrub pines with an unmanned machine workers have nicknamed ARTS (All-purpose Remote Transport System).

Using joysticks resembling an antiquated video game, workers direct the ARTS to clear the pines in what is known as Area G, a heavily used training range where workers have found empty tear-gas canisters, grenades and grenade launchers. Once the area is cleared of trees, the Towed Array can search for ordnance. Later, the refuge will reopen the area to hunters.

"We haven't found anything that indicates there are explosives here," said Foster Wheeler quality control supervisor George Bridgeman, "but we just don't know yet."

Officials with both agencies acknowledge they're working backward to clean up the refuge.

Under the Base Realignment and Closure Act of 1988, Fort Meade and several other military bases gave up thousands of acres under one of the military's largest downsizing efforts.

In most cases, such as the transfer of Tipton Airfield to Anne Arundel County, the Army was required to clean up property before transferring it.

But the Army didn't launch a large-scale cleanup of the Patuxent site because Congress required that the land be transferred to the Interior Department by September 1991. Army officials said lawmakers and community leaders fretted the property could end up in the hands of developers.

The transfer document called for clearing the land up to 12 inches deep for ordnance. But wildlife officials argued that such deep trenches would destroy habitats.

"To really have cleared the area effectively would have made this area one big clear-cut, which was not in our interest at all," said Brad Knudsen, who manages the refuge for the U.S. Fish and Wildlife Service. "That would in some ways defeat the purpose of it being transferred."

As a result, in the early 1990s, the Corps of Engineers studied the land down to 6 inches below. They removed more than 1,000 pieces of unexploded ordnance.

Though no one has been injured by ordnance on the refuge, it has caused complications.

About 15 times a year, hunters find unexploded ordnance and alert the staff. Every time staff members want to put up a sign or repair a culvert, a team of ordnance specialists must check the land - and Knudsen says that can cost up to $5,000. That's one reason, he says, that so few signs are posted there.

Those who enter the North Tract must sign a waiver acknowledging that they are aware of the ordnance and that the government is not responsible if they get hurt on the property. North Tract staff members say that only one visitor - out of about 60,000 who visit each year - has refused to sign the waiver.

"It's a threat," Knudsen said of the ordnance, "but people probably have a much greater chance of getting hurt on the way to the refuge."

Baltimore Sun Articles
Please note the green-lined linked article text has been applied commercially without any involvement from our newsroom editors, reporters or any other editorial staff.