An ailing pond received a dose of medicine yesterday when highway workers sprayed it with lime.

The state Department of Natural Resources diagnosed a 4-year-old sediment pond in Gambrills as highly acidic last year.

The State Highway Administration had wanted to drain the pond, known as Lake Median, into Jabez Branch, a highly sensitive tributary of the Severn River.

But SHA officials canceled their plans after DNR biologists said the pond's 3 million gallons, located between the northbound and southbound lanes of Route 3, had the acidity of lemon juice.

Yesterday, an SHA consultant prescribed the antidote: a 55-gallon drum of lime and a "hydro-seeder," a tank truck that sprays liquids.

Road workers sprayed the pond at 8:30 a.m.

If and when the SHA may pump the pond dry is uncertain, said Edward Stein, assistant to SHA's chief engineer.

DNR and SHA officials seem willing to let sleeping dogs lie.

Because the pond's depth dropped over the winter, Stein said, "we feel we have enough cushion now that we won't have to pump it this year. As long as we can keep it in the median, we can control it."

Highway engineers initially feared the pond could flood a storm pipe and wash out a portion of the road.

DNR officials "said if they had their druthers, they would rather leave it asis," Stein added.

The final decision won't be made for several weeks.

Consultant James W. Gracie will continue to monitor the pond for acidity. That testing could include introducing hatchery-bred trout into the pond, Stein said.

"All we have done is neutralize the water," Stein said. "We haven't done anything to seal off the cause."

Engineers traced the problem to glauconite, a naturally occurringsoil that turns highly acidic when exposed to oxygen.

Stein said some glauconite would have to be excavated, a synthetic cloth would be laid down, and clean top soil returned.

Lina Vlavianos, a environmental activist who alerted DNR officials to the problem at Lake Median, said she would urge the SHA to put an end to matter.

"My instinct would say, 'Let's do it all right now and stop monkeying around,' " said Vlavianos. "The key is testing the water with the trout. If the fish survive, the water can be released at a slow rate and the glauconite can be capped."