Irate residents have hired three attorneys to fight a proposal to put 225 mobile homes on a 50-acre tract near a state-managed wildlife area here.

In the last two weeks, Charles County planning officials have heard more than 20 hours of testimony from opposing sides at a series of often-rancorous meetings and have given the residents until the first week in August to produce expert witnesses to bolster their arguments against the controversial trailer-park development.

William F. Chaney and his wife, Patrice, want the county to change the zoning for 50 of their 350 acres from residential single-family to a newly created mobile home park zone (MH) so they can build a state-of-the-art trailer community called Hidden Pines.

The community would be the eighth mobile-home community in Charles County, where planners estimate at least 2 percent of its 80,000 residents live in trailers -- about 800 of those on private lots.

But the appearance of Hidden Pines would be "dramatically different than anything in Charles right now, as would be its clientele," contended Charles D. Ellison, an engineer and land planner with D. H. Steffens Co., the firm handling the Chaney presentation before the planning commission.

The mobile-home development would be buffered from view on all sides and would avoid the traditional parking-lot lineup by clustering trailers along cul-de-sacs off a long main loop, Ellison said.

Ellison said "manufactured homes" is the correct term for the more permanent units planned in the Ripley community, with prices ranging from $15,000 to $45,000.

"Whether you call them manufactured homes or trailers is just window dressing," said Gary Alexander, the attorney representing the Ripley Citizens Association and the Committee to Save Myrtle Grove. "This is obviously a high-quality development," Alexander said, "but it doesn't solve the environmental and density problems."

Alexander said his presentation Aug. 5 will argue that the rezoning represents "a fundamental change in the neighborhood . . . a doubling or tripling of the population in a small rural area . . . that is clearly not allowed, even using the floating mobile-home zone." He said the land planners and environmental experts he calls will argue against the increased density so close to a wildlife area.

A technical staff report will follow the August meeting, and then the planning commission's zoning recommendation will go to the county commissioners, who will make the final decision after yet another public hearing.

Residents at a public hearing last week said they also oppose the Hidden Pines project because they fear it will increase the number of failing septic systems in an area already known for contaminated shallow wells and poor drainage.

George B. Wilmot spoke against the rezoning for the Southern Maryland Audubon Society, saying sediment runoff and effluent discharges would have an adverse affect on creeks and bird refuges near the 831-acre state-managed and -protected Myrtle Grove hunting and wildlife area.

Wilmot said retaining the current R-2 zoning "would be a much better buffer for this major public land investment along Mattawoman Creek."

State officials with the Maryland Forest, Park and Wildlife Service want the rezoning request denied because of safety concerns. "We are not against mobile-home developments per se; it is just our feeling that residents of this park are bound to treat the adjacent land as an extension of their own back yard and wander in," said Jim Mallow, assistant director.

Besides using the shooting range, Mallow said as many as 60 sportsmen at a time hunt ducks, deer, quail and rabbits at Myrtle Grove.

Many other residents worry that once a mobile-home community is approved for the 50 acres, the developers could keep coming back to expand the trailer park. Patrice Chaney told the planning commissioners that she and her husband have no plans at present to develop the 300 acres surrounding the park.

"What assurances do we have that the Chaneys won't build another St. Charles City down there?" one irate resident yelled out at the meeting. He was referring to the county's largest planned residential development, in Waldorf.

County officials say that well-planned and aesthetic mobile-home developments are preferable to scattering trailers across the county.