Montgomery County Council Unanimously agreed Tuesday to earmark nearly $6 million to set up a sludge-composing facility in Dickerson.

A citizen's group opposed to the plan reacted quickly after the council's vote.

Steven P. Quarles, chairman of the Sugarloaf Citizens Association, said his group will consider legal action to prevent the county from setting up the facility by its Jan. 1 target date.

The county must dispose of about a quarter of the 1,500 tons of sludge -- sediment deposited during sewage treatment -- produced daily at the Blue Plains waste water treatment plant in the District.

Montgomery and Prince George's counties, both of which use the Blue Plains facility, have in the past alternated burying sludge.

But as of Jan 1, said Alexander Greene, an aide to County Executive Charles W. Gilchrist, the two counties will no longer share the dumping responsibility. Each jurisdiction must come up with a plan to dispose of its share of sludge.

Many nearby residents agree with county officials that the current practice of burying sludge is unacceptable.

But they prefer that the composting site remain outside Dickerson, a quiet town situated in the shadow of picturesque Sugarloaf Mountain.

County officials say the proposed Dickerson plant is an interim facility until a permanent composting site in Calverton, near the Prince George's County border, is completed.

But because a flurry of lawsuits aimed at halting the Calverton operation have put the site's opening date in doubt, county officials will not say how long they will use the Dickerson site.

It was the uncertainty about how long the Dickerson site will be used and the fear of what many Sugarloaf area residents perceive as a threat to their rural environment that brought a small army of citizens earlier this week to a Montgomery County Council public hearing on the Dickerson facility.

Quarles, who is deputy undersecretary of the Department of Interior, gave emotionally charged testimony condemning the county's plan.

Labelling the planned facility at Dickerson a "down-and-dirty operation," Quarles said residents fear their wells and ground water could easily be contaminated by runoffs from the composting site.

He said there are no provisions to enclose buildings where the sludge, mixed with wood chips, is dried.

The Calverton facility is on the sewage system and those living near it use municipal water. But, Quarles said, "Our groundwater is our drinking water and all that makes our homes and farms livable."

The Dickerson facility is to be built on Martinsburg Road adjacent to the Pepco power plant. The county will buy the land for $1.4 million.

The total project will cost about $6 million. The county, however, will recover about $4 million of that sum from the Maryland Environmental Service, which will operate the composting facility under a lease from the county.

Because the county plans to spend about 2 million on the project and to spend more money in the future to haul the sludge by rail to Dickerson, the citizens' group questions that the Dickerson site will be temporary.

"This is a horrible Catch-22 you have us in," Quarles told council members at the public hearing.

"We are afraid to ask for design improvements [and] better environmental controls, to make the facility's presence more benign, because we know those controls and improvements cost money.

"And the more money spent on Dickerson," he added, "the more likely [it is that] the facility will be permanent."