The Loudoun County Board of Supervisors this week denied a special-exception approval for a controversial video arcade at the Sterling Park Shopping Mall, and it said the owner must close down the business within 90 days.

The board's 4-to-4 vote turning down the special-exception application followed a public hearing last month during which members of the Loudoun County sheriff's department, business owners at the mall, and other residents complained that Rag Time video arcade attracted large numbers of youths who congregated outside the arcade, allegedly dealing drugs, fighting and harassing customers going to other businesses.

Pan Soon Lim, owner of the arcade, had denied that her customers caused problems that have been associated with the arcade.

During nearly an hour of debate before the vote, several supervisors suggested approving the special exception for six months with certain conditions imposed on the owner, who has operated the arcade since April without the necessary special exception approval because, she told the board last month, she did not realize that it was required.

"The applicant has not had the opportunity to operate under any specific guidelines or conditions of a special exception," said Mercer supervisor Thomas S. Dodson, arguing for approval.

But Sterling supervisor Andrew R. Bird III, whose district includes the shopping mall, said that even though closing down the arcade "may not totally eliminate any loitering problems, it's the nature of this business that draws it." He also said, "This sort of use and the interest of the public health, safety and welfare is not compatible . . . regardless of the ownership."

Voting to approve the special exception were Dodson, board Chairman James F. Brownell of Blue Ridge district, Guilford supervisor Betty Tatum and Leesburg supervisor Frank Raflo.

Voting against approval were Bird, Broad Run supervisor Steven Stockman, Dulles supervisor Ann Kavanagh and Catoctin supervisor Frank Lambert.

The board also voted Monday to hold a public hearing on repealing a tax on livestock and farm machinery that has not been enforced for more than a decade. The tax of 1 cent per $100 assessed value applies to horses, mules, cattle, sheep and other farm animals, as well as grains raised to feed farm animals, and farm equipment.

The county staff said property tax reporting forms could be simplified by formally repealing the tax.

In other matters, the board:

* Raised the salary of Sheriff John Isom to $44,367, effective Jan. 1, saying that the constitutional officer should receive a salary no lower than the lowest of other constitutional officers in the county.

* Raised the salary of county administrator Philip A. Bolen to $54,068 effective Jan. 1, and increased the salary of county attorney Edward J. Finnegan to $49,041 effective March 1. The raises were routine longevity increases, the county staff said.

* Approved the hiring of a third assistant county attorney.

* Approved granting county employes a full day off on Christmas Eve as well as Christmas Day.