A Charles County citizens group contesting a pending zoning change that would restrict mobile home use in the county, where housing for low-income families is in short supply, proposed an alternative yesterday that would soften the proposed regulation.

Members of the newly formed Trailer Ordinance Revision Committee, a coalition of mobile-home park owners, church groups and housing-rights activists, met with County Commission President Marland Deen and other officials to head off regulations governing mobile homes and lot sizes that would be the strictest in Maryland.

"We don't support substandard housing," said Robert Sondheimer, head of the Charles County Housing Coalition and a member of the mobile-home committee. "We would, however, like to see some of the unnecessary amenities deleted from the ordinance so that trailer parks could be a place where low- and moderate-income people can afford to live." About 2 percent of the county's 75,000 residents live in mobile homes.

Under proposed amendments presented to the county commissioners by the planning commission Aug. 16, it would be illegal to install mobile homes on lots of less than three acres outside of parks. Mobile-home parks would be required to have at least 50 acres, and could have no more than five units per acre. Owners would be given three years to comply with those and other provisions.

The coalition's alternative would reduce the minimum lot size for individual mobile homes installed after the law is passed to one-, two- or three-acre sites--whichever corresponds to lot sizes for single-family homes in the same zone. The group pressed for a "grandfather" provision that would allow existing individual mobile homes that don't meet the new requirements to remain.

County officials said the ordinance is needed to eliminate substandard housing conditions, and noted that in some cases, mobile homes have no plumbing or electricity.