There is a reason why Huntsville resident Lynda Ladd raised her herb garden off the ground.

She is nervous about hazardous chemicals buried underground in nearby Redstone Arsenal.

"You find out it's in your own backyard. That's very concerning," Ladd said. "That's a walking disaster zone, and I am concerned for everybody's health."

Following World War II, the U.S. intentionally dumped tons of unused deadly and dangerous military munitions and chemical weapons on the installation. Many of these chemicals, blister, choking and blood agents were made in Nazi Germany, Japan and on Redstone Arsenal.

Clint Howard, the chief of the Environmental Restoration Program, said Redstone was targeted as a dumping site since it had experience making such weapons.

"Since we were so good at making those types of weapons, we were also good at demilitarizing those types of weapons," said Howard, who for the last 10 years has led the environmental restoration program at Redstone.

Howard said the testing and monitoring program at the installation began in the 1970s, but most of the cleanup did not really start until the Alabama Department of Environmental Management took over about 10 years ago.

Still, there are an untold thousands of munitions and contamination from chemicals weapons still buried, making it so the groundwater cannot be safely consumed. That includes areas surrounding Redstone.

"We do not allow wells to be installed for drinking on Redstone or in the operational vicinity," said Howard, whose office works with nearby cities, including Huntsville, to pump in fresh water.

Outside the perimeter of Redstone, well-water restrictions are in effect for residents like Ladd. While Howard maintains those areas are continually monitored, Ladd is not so sure.

Howard said the most contaminated or "dirtiest" area on Redstone is in the southern area, in mostly wetlands and creeks, just due north of the Tennessee River.

"This is the area where we stored some of the worst chemicals during World War II," said a Redstone scientist and environmental expert, Jason Watson, who led our news crew out to an area called RSA (Redstone Arsenal) 068.

Watson said after his team marks off a site and studies it, they begin in earnest to remove materials both above and below ground.

"The next step would be to go in and remove those items and dispose of them through whatever regulations through a treatment system or through a landfill. We've got several different options," said Watson.

Although Watson and Howard admit there are challenges ahead, including an estimated 20 years to complete cleanup at an estimated cost of $900 million total, the hazardous waste removal is making progress.

A process called Electric Resistive Heating treatment has removed approximately 52,000 pounds of volatile organic compounds at four separate sites in the last two years.

Redstone also employs another system to remove bomb shells and detonate them and decontaminate any chemicals inside. It's called the Explosive Destructive System.

However, one of the more sensitive areas still being cleaned up is the area surrounding the George Marshall Space Flight Center where rocket test stands are located.

"We found what we call UXO (unexploded ordinance) subsurface at Marshall 3, but they were like 2 feet underground," said Watson. "There are over 10,000 subsurface anomalies and some of them could be dangerous, but we are finding the majority of those were demilitarized correctly and made non-hazardous."

For more information about the current remediation program at Redstone Arsenal, contact Team Redstone on its Facebook page here.