A group of Army and Aberdeen officials have devised a four-point plan to deal with perchlorate, a hazardous industrial chemical found last month in groundwater near the town's drinking water wells.
Aberdeen Proving Ground and city officials agreed to:
Conduct more tests to determine the extent of the contamination.
Monitor well water more closely.
Develop an interim plan for closing the wells and acquiring emergency water, if necessary.
Work on a long-term remediation plan, perhaps patterned after an APG-Harford County well protection agreement designed to guard the county's wells from a plume of industrial solvent contamination near the western boundary of the sprawling base where the Army tests weaponry.
Aberdeen and APG agreed to conduct monthly tests of well water, and Aberdeen will also test finished water, said Peter Dacey, city manager. Aberdeen's most recent well water and finished-water tests came back without perchlorate traces, Dacey said.
The Army performed additional water tests that will be released today, said Ken Stachiw, APG's environmental restoration chief who met yesterday with environmental and community agencies to discuss the perchlorate treatment options.
Perchlorate, which is used primarily in explosives, was found within 300 feet of the city wells that sit along APG's northern boundary with the city, sparking concern in the community and city government.
Base officials conceded yesterday that no tests have been conducted closer to the wells, so the full of extent of the contamination is not known. "We're in the process of doing that now," said Stachiw. He said workers are sinking probes into the ground close to the wells to take ground water readings, and results should be complete early next month.
Richard J. McIntire, Maryland Department of the Environment spokesman, said the Army is using more than 30 probes, some within 100 feet of the wells. MDE has been pleased with the Army's response, he said.
"MDE doesn't consider this an immediate threat to the wells," McIntire said. If perchlorate reaches the wells, he said, "We don't expect to see the levels of the contaminant reach detectable levels, especially in the finished water."
Army water test results to be released today will guide the Army's response, said George Mercer, an APG spokesman. He stressed that APG could make no final remediation plans without approval from the Department of the Army.
"They've backed us in the past - with the Perryman project for example - so there is a precedent," he said.
In the 1990s in Harford County's Perryman well area - also on the boundary with APG - the industrial degreaser trichloroethene was found in two of the county's seven wells, said Jackie Ludwig, a Harford County water and sewer official. Traces of explosives were also found along the boundary, she said.
The Army did short-term cleanup of the water and, as part of the long-term remediation, is paying for a $2.2 million water treatment plant, which is under construction, she said.
Ludwig, chief of administration and engineering for Harford's water and sewer division, said Aberdeen officials have not contacted her office about the perchlorate problem. The county provides about 500,000 gallons of water a day to the city.
In the event perchlorate reached the Aberdeen wells, forcing them to shut down, the city would need an alternative source for the approximately 1.7 million gallons of water a day it uses. "Our agreement doesn't provide for that much water," she said.
Dacey, the city manager, said Aberdeen had not contacted the county but planned to.
"We have turned to them in the past. They're a good neighbor, and we would expect them" to provide water in an emergency, he said. "The other option is using water from Chapel Hill," he said, referring to a water treatment plant that gets water from Deer Creek.
Aberdeen took over the plant from APG and is operating it, with MDE consent, without a permit while its application for one is being processed. The current permit does not provide for drawing more water from Deer Creek than APG uses.
McIntire said any change in the city's sources of water would need MDE approval.
"That's a bridge we have to cross when we get to it," he said. "There are a number of options, but we don't know what all of them would be. Hopefully, they will not lose any of these wells."
Glenda Bowling, vice president of the APG Superfund Citizens Coalition, said the perchlorate was discovered in the area more than a year ago. The recent discovery that it is closer to the wells than thought reinforces the need for a buffer zone around the wells that would limit activity and development in the area, she said.