Residents of Bethany Beach, Del., have won a court battle against a developer who wants to build a 432-unit, eight-story condominium vacation complex along a 1-1/2-mile stretch of seashore.

The Chancery Court of Delaware ruled May 1 that the Sussex County Council had failed to comply with procedures set forth in the county's home rule charter when it granted a rezoning for the Sea Colony North property to Carl M. Freeman Associates, a Silver Spring developer.

At issue were the advertising the council should undertake to alert county residents about the rezoning and the kind of vote taken.

In 1974 the same court overturned a decision to rezone the largest privately held tract with as much as 8,000 feet of shoreline. It ruled that the council did not have enough information on which to make a judgment. Freeman Associates, with a multi-million-dollar project at stake, reapplied in 1977.

Washington attorney William Green, who owns a condominium apartment north of the site, brought the action against Freeman on behalf of himself and five other area residents. tA long-time opponent of the project, Green said he was "overwhelmed and overjoyed" by the verdict. "There were a lot of happy people at the (last) weekend parties in Cotton Patch Hills," he added.

The 24-acre Sea Colony North site is north of Bethany and Cotton Patch and south of the Watergate town house condominium, where Green has a place.

Freeman executive Norman Dreyfuss said this week that "legal remedies" will be taken against the decision "because the error was procedural, not substantial."

Currently, the Silver-Spring-based Freeman firm is completing the eighth and final high-rise condominium building at its 900-unit Sea Colony complex. It began the development 10 years ago on the southern edge of quiet, low-rise Bethany Beach. Dreyfuss said no start on Sea Colony North is planned until the current development is sold out.

Since sales were opened this spring, Sea Colony has signed up 22 buyers for apartments in the new 108-unit building.