Army officials are seeking permission to cut back on monitoring of one of Aberdeen Proving Ground's most complex and polluted sites, an old chemical munitions dump that for decades discharged contaminated ground water into the Gunpowder River, a tributary of the Chesapeake Bay.
Based on previous results, testing can be done less frequently without imperiling the environment or endangering the public, the officials say.
But community members are concerned that less-frequent testing could pose a risk to public health and safety because the site, called Old O Field, contains a foul brew of decomposing metals and chemical warfare agents such as mustard and lewisite, and residue from solvents used over the years to try to destroy the agents.
It's the combination of the three types of contamination that makes Old O Field unusual, said Cindy Powels, cleanup project officer. "It's more complex than average sites."
But she said water testing has shown consistent results for eight years, since the Army built a $30 million permeable landfill cover and ground-water treatment system to capture and treat pollution before the water flows into the river.
Cutting back on some of the testing will not compromise the progress, or public safety, she said.
The proving ground wants to test discharged water from the treatment system once a month instead of twice, she said, and to cut back on quarterly tests of wells around the landfill that it monitors for changes or new appearances in contamination.
The Maryland Department of the Environment has approved the changes, and the Environmental Protection Agency has indicated that it will, too, she said.
Some area residents question whether cutting costs at such a toxic site is wise.
"Landfills don't get better with age," said Cal Baier-Anderson, a University of Maryland toxicologist and technical adviser to the Aberdeen Proving Ground Superfund Citizens Coalition.
The coalition maintains that much is unknown about the site, and the potential for failure of the system is real - through a release of agent or explosion of old munitions. With recreational boaters nearby on the Gunpowder River, caution is needed, she said.
The proposals come as Old O Field also is under review also by the Army Environmental Center. APG environmental officials and the center are awaiting a report from site contractor, General Physics, to consider operational cost-cutting strategies. Costs for operation and maintenance have run from $1 million a year to more than $2 million a year over the past eight years, Army officials say.