The Prince William County Planning Commission, bowing to pressure from hundreds of residents of the Montclair area, last night recommended denial of a request to build a gasoline station at the entrance of the 1,600-home community.

The County Board of Supervisors will make the final decision.

About 200 Montclair residents attended the meeting and more than 100 signed up to speak against the proposed facility, alleging it would cause pollution, generate unwanted traffic and create a safety hazard.

"We have surveyed 906 people and 61 percent don't want this station under any circumstances," said Montclair spokesman Bruce Woodruff.

The decision to recommend denial of the application from the Mobil Oil Corp. came after months of negotiations between Mobil, county staff and residents.

Mobil spokesman Michael D. Lubeley said the company made 20 concessions to concerned residents. He said the firm was willing to scale down the structure, landscape the property and limit hours of operation at "a considerable expense to Mobil."

The proposed station is part of a shopping center planned for a four- acre commercially zoned site on the corner of Dumfries Road and Country Club Drive. Although the developers do not need the supervisors' permission to build a shopping center on the land, gasoline stations must be granted special permits.

Lubeley said the developers of the site, Montclair Associates, may not be able to build "a discreet, quality shopping center" without the money they would receive from a Mobil station. "I don't want you to consider that a threat, but it is something to consider," he said.