Saying the Gaviota coast was no place for "trophy homes," conservationists on Friday appealed the county's recent over-the-counter approval of a 15,000-square-foot estate west of Refugio State Beach.

The proposed Bean Blossom project would be built on the north side of Highway 101 at Rancho Tajiguas, the largest property on the rural coast. It would include a two-story, seven-bedroom, eight-bathroom home; a four-car garage; guesthouse; pool; cabana; and barn.

The estate would be set back from the road, partially hidden by a ridge and only briefly visible to driversspeeding by. But the nonprofit Gaviota Coast Conservancy contends it would set a bad precedent. The owners of Rancho Tajiguas have also applied for permission to build another estate, totaling 11,000 square feet, just to the east. The county also is reviewing their petition to adjust the boundaries of four lots for future homes.

"Everybody wants the Gaviota coast to stay the same," said Mike Lunsford, the conservancy president. "A staged series of trophy homes begins to change the character of the coastline -- not only the appearance of it but the underlying economics of agriculture. It's not a road we want to go down."

The conservationists' appeal represents their latest attempt to hold off development on the Gaviota coast, a region determined by the National Park Service to be worth saving for its virgin canyons, wild shores and sweeping mountain views. Although a railroad and highway pass through it, the sloping rangelands west of Coal Oil Point still offer a glimpse of what old California was like.

Last spring, a conservancy campaign to win a National Park designation for the Gaviota coast failed in the face of landowner opposition. County officials say it is now up to the landowners to come up with a joint plan for what should be developed on the coast, and where.

On Friday, the planners defended their decision to approve the Bean Blossom estate, saying it complied with zoning rules. In light of the appeal, they said, they will first seek a negotiated agreement among all the parties. If that effort fails, the appeal will go to the county Planning Commission.

"If these projects are found consistent with all the existing policies and regulations, there is no reason for us to deny them," said Dan Klemann, a county planner who gave the estate the stamp of approval.

As a single home, the Bean Blossom proposal did not trigger a requirement for an environmental report or a commission hearing. However, the county Board of Architectural Review scrutinized the plans, asking the developers to move the estate well back from Highway 101.

The board then exempted Bean Blossom from county height limitations for hillside development, approving roof elevations of 24 feet, rather than the norm of 16 feet.

The architectural board said the Bean Blossom estate would be compatible with the gentle grasslands in the vicinity.

In any case, Mr. Klemann said, it would not be the first large home built on the Gaviota coast. One big estate, formerly owned by John Travolta, is surrounded on all sides by Rancho Tajiguas, he said. Another has been built in full view on the north side of 101, and several others are clustered out of sight.

Rancho Tajiguas is owned by 10 members of a Swiss family living in Europe. John Vallance, vice president of MAZ properties, a Los Angeles-based firm that runs the ranch, could not be reached for comment on Friday. But in the past, Mr. Vallance has said the Bean Blossom estate would be a second home for one of the family members. The whole project would occupy less than two acres of one 107-acre lot, Mr. Vallance said. The ranch itself covers 3,600 acres.

"If somebody wants to live in a big house, I certainly don't condemn them for that," Mr. Vallance said.

Mr. Lunsford wondered why the houses have to be so large if they are destined to be second homes.

"Can't they be smaller and more suitable to the style of the Gaviota Coast?" he asked.