A proposal to expand the Prince Frederick wastewater treatment plant near the Parker Creek watershed has prompted environmentalists to seek assurances that the $3.5 million project will not damage the fragile area in the heart of Calvert County.

"I wonder how much of the total eventual [development] of Prince Frederick is the Parker Creek watershed going to be asked to absorb," said Joy A. Bartholomew, president of the American Chestnut Land Trust, a private nonprofit organization that owns 816 acres in the watershed and manages an additional 1,600 acres on behalf of the state and The Nature Conservancy.

At a public hearing on the project last week, Bartholomew asked county commissioners to put off a decision until they can hold a public forum to educate residents, landowners and other interested parties about the project. While not objecting to the plan, Bartholomew said the public should become part of the decision process.

"It's a tough and delicate balance between making sure we have economic development and preserving what is best about the county," Bartholomew said. "We'd like to reserve the opportunity to make more specific comments" until after a public forum, she said.

The commissioners agreed to hold open the record on the matter for three weeks and said they would hold a public forum on a weeknight during the interim, to allow for more discussion of the plan. The forum has not yet been scheduled.

Water and sewer officials want to build a spray irrigation wastewater treatment plant on 180 acres off Tobacco Ridge Road in Prince Frederick. The plant, which would be built at an existing pump station, would be an expansion of the current Prince Frederick treatment facility in Barstow.

The existing Prince Frederick plant can handle 450,000 gallons a day. County officials say the plant is already treating 325,000 gallons a day and they expect it to reach capacity by 2001. The new plant would be designed to handle an additional 300,000 gallons a day immediately.

The proposal calls for a spray irrigation wastewater plant, which means that wastewater pumped into the plant would be treated and then sprayed onto land in the surrounding area. The site is at the edge of the protected Parker Creek watershed, home to a rare and endangered plant species. The American Chestnut Land Trust is concerned that the new wastewater plant might degrade water quality in Parker Creek or hurt the fragile ecology.

Dennis Brobst, director of the county's Water and Sewer Department, said the spray is "almost drinking water quality" and will be used to irrigate a hardwood forest. "The trees are now scrub," he said. "Our plan is to purchase hardwood trees and interplace them."

Funding for the plant would come from the state and the county's sewer fees, with no money coming from the general fund, Brobst said.

The expanded plant is needed to keep up with growth in the county seat, particularly the new community college campus planned for Prince Frederick, Brobst said.

"The new community college is going to be such a significant user that this plant has to be on line before the college opens," he said.

Construction is expected to take 13 months and could be completed by 2001, Brobst said.