A map with last Sunday's Harford County Sun article, "Army undertakes cleanup," showed an incorrect location of the contaminated 26th Street Disposal Site on Aberdeen Proving Ground.
A corrected map appears on Page 4.
The U.S. Army plans a 30-year, $43 million cleanup of two contaminated sites at Aberdeen Proving Ground that may contain unexploded ordnance, laboratory waste and other potentially hazardous materials.
The plan for the sites, both on the Environmental Protection Agency's "Superfund" list, calls for the Army to remove the materials and take other measures to protect the environment.
Both sites are at the Edgewood area of the proving ground. One was used as a dump; the other was a burning pit for munitions and chemicals.
A public hearing on the plans for the sites will be conducted at 11 a.m. tomorrow, at the county library branch, 2205 Hanson Road in Edgewood.
The Army developed the plans and is conducting the hearing as part of EPA requirements for Superfund sites.
The Army is not certain how long it will take to finish the project or how much it will cost because the extent of contamination is unknown, APG spokeswoman Barbara Filbert said.
However, the project has an estimated cost of $43 million, and may not be finished until 2010.
"In both of these cases, we don't know exactly what is there," Filbert said. "At this point, we do not believe they pose any threat to humans or wildlife."
One site, called the Bush River-26th Street Disposal Site, is a 1-acre area used between the 1920s and 1970s to burn gas mask canisters containing activated carbon.
The canisters were commonly burned in packed wooden boxes, and the unburned portions were left in a ditch at the dump, according to a report prepared by consultant Roy Weston Inc. of West Chester, Pa. The site may be contaminated with heavy metals, such as copper, silver and chromium, the consultant said.
Another part of the site, in a remote area north of Kings Creek, was used as a dump, the report says. It is believed to contain scrap metal, incinerated grenades and laboratory waste.
"There is a potential for migration of the possible contaminants from the site into nearby water bodies and the adjacent marsh and wetlands," the Weston report says.
Weston outlined a step-by-step procedure for the site's cleanup, starting with a search for unexploded ordnance that would be removed and disposed. The report does not say how the ordnance would be disposed.
Other debris and waste would be collected and taken to the proving ground's Decontamination/Detoxification Facility for thermal treatment, a process that burns off contaminated materials.
Soil at the site will be tested for contamination. Tainted soils will be stockpiled on site for "future disposal" by the Army, Weston says. The report doesn't specify how the soil would be disposed.
The second site, called the J Field, contains numerous pits used to burn toxic materials between the 1940s and 1960s. The 1-acre field is at the tip of the Edgewood peninsula, off the Gunpowder River.
Munitions, chemical wastes, chemical nerve agents and riot-control chemicals were among the materials burned at the site, the Weston report says. The site is believed to contain heavy metals and chemical compounds, such as lead and vinyl chloride.
Soil and ground water at the burning pits will be tested for contaminants. Weston recommends that a separate study be prepared to handle any tainted soil and ground water.
Much of the site has become overgrown and the banks along the Gunpowder are eroding, threatening the stability of the burning pits, the report says. Weston calls for the Army to reinforce the river banks to prevent further erosion.
Unexploded ordnance and other debris will be removed from the field in the same way that such items are to be handled at the Bush River-26th Street dump.
The J Field site contains a open-sided concrete structure, called the Prototype Building, originally used to test bombs.
The building recently has been used for storage. Four drums containing unknown materials in the building are to be removed as part of the Army's plan.
Copies of the Weston report can be reviewed at the Edgewood and Aberdeen libraries. Copies also are available at the APG public affairs office by calling 278-2012.
Written comments may be sent to: Aberdeen Proving Ground Support Activity, attention of STEAP-SH-ER (Ken Stachiw), Aberdeen Proving Ground, Md. 21010, by June 4.
A public hearing on plans for cleaning the two Superfund sites will be conducted at 11 a.m. tomorrow at the county library branch, 2205 Hanson Road in Edgewood.