In a move that pleased Rockville officials and angered an Arlington-based developer, the Montgomery County Planning Board recommended for a second time that the county reject plans for a $300 million office park just outside Rockville.

The planning board voted 4 to 0 last week to urge the County Council to deny a request to build a 1.4 million- to 1.5 million-square-foot hotel, office and retail complex north of Montrose Road along I-270 -- one of Montgomery's most congested intersections. The board members also told the developers that they would not approve any project larger than 900,000 square feet at the site.

The board action surprised the developers, who scaled down their original plan for a 1.7 million-square-foot complex -- a proposal rejected late last year by the planning board. The developers said they thought the second application had met the concerns initially raised by the board.

Both the first application and the second, less ambitious plan for the Fortune Parc project had been endorsed by the county's planning staff.

"This is totally uncharacteristic of what we were led to believe about our application and the plans for development in that area," said David Murphy, Fortune Parc's director of development. "I don't understand their decision after we brought (the size) down. I think this establishes a problematic precedent for the I-270 corridor."

The plan now goes to the county hearing examiner, who must issue a report to the County Council within 45 days. The council will then have 60 days to make a decision, but could pass a resolution extending that time limit.

The attempts of Fortune Parc backers to build on the 49-acre parcel have frustrated the developer and raised the ire of Rockville officials. Because of the parcel's location just outside the city, Rockville residents and officials fear the city will get all of the extra traffic from the project but none of the estimated $1 million in tax revenue it would generate.

Rockville officials have long considered annexing the site, but for now, it stays in the county's domain.

Joe R. Davis, planning coordinator for the county board, said the decision "was an attempt to see that development of the site was more compatible with development to the north in Rockville."

Davis said the developer's second proposal "met many of the criteria" that the board, in its first rejection, indicated would be necessary for approval of such a complex.

Rockville Mayor Douglas Duncan said he is "gratified" not only by the planning board's rejection of Fortune Parc, but by the board members' comments that any change of heart by the board would require the project to be reduced to 900,000 square feet -- about half the size of the original proposal.

In April 1985, Fortune Parc developers approached Rockville officials with plans for the original 1.7 million-square-foot project. The developers asked the city to change the zoning to allow a development of that scale on the property. That request came with the assumption that the city would, in short order, annex the land. But, by June 1986, with developers losing patience over the city's failure to make progress on the zoning change, the firm turned to the county for permission to build on the site.

The result has been a protracted land squabble between the city and the county, with Rockville officials trying to persuade the county to act on an agreement that would allow the city to annex the site and two other lucrative county properties.

Since the developer abandoned efforts to deal with the city and sought a more receptive audience in the county, Rockville officials have said that their only chance to control the land is to move quickly on an annexation agreement with the county.

Duncan said the Jan. 11 planning board decision was, "good news for the neighbors of that area and for the people of our city. The size is reduced to something we can live with. But the denial also gives us more time to work with the County Council to try to work on the (annexation) agreement."

But, County Council member Michael L. Subin, a member of the council committee that would first consider the annexation agreement, acknowledged that the county does not have much incentive to move quickly on the annexation issue.

"We don't get anything out of it, most think. And, with budget season on us, (our schedule is) chock-full," Subin said. "It would be six to eight months, I'll bet."