Prince William County will ask the state to add $214,225 to a $1.4 million commuter bus grant the state has approved for the county.

The Board of Supervisors also agreed Tuesday to take legal action against the operator of a noisy lawn mower repair shop and refused to accept a report on public drainage systems because, they said, they only had five days to review the report that took more than two years to complete.

The Virginia Department of Highways and Transportation approved a $1.4 million grant last August for the purchase of up to 20 remanufactured buses. The county plans to lease out the buses to independent operators who will then run commuter services from the county to the Pentagon, Crystal City and the District of Columbia.

However, supervisors said the 20 buses will cost more than the original estimate of $70,000 each.

The county is asking the state for an extra $200,000 for the buses and also another $25,000 for advertising and a contingency fund. The county will pick up 5 percent, or $11,000, of the extra grant appropriation, if it is awarded.

One of the major goals of the county is to improve commuter transportation. Thousands of county residents commute to their jobs outside the county.

Meanshile, Woodside resident Bill Blackman asked the board to help alleviate the noise from a lawn mower repair shop in the Woodside Retail Park off Rte. 1.

The repair shop is only 30 feet from Blackman's home and he said the noise emanating from the shop has disturbed his whole neighborhood. To illustrate his point, he played a tape recording of a lawn mower motor into the board room microphone. He said the recording was taken inside his home at 8 on a Saturday morning.

Supervisors asked the county attorney to take legal steps against the repair shop.

Supervisors also voted to defer the acceptance of a study on drainage problems in the county for 60 days.

"Here is a case of a two-year analysis," said Supervisor Joseph D. Reading. "We get it on a Thursday afternoon and are expected to rubber-stamp it on the following Tuesday."

Supervisors will send the report and its recommendations to a public hearing after 60 days, and vote on it sometime later.

In other action, the supervisors:

* Commended Gar-Field High School sophomores Kathy Murphy and Kim Harris for creating an active chapter of Students Against Drunk Drivers in the county;

* Abolished the CETA program in the county, which all local governments must do under new federal laws, and replaced it with a manpower council;

* Approved the purchase of a new ambulance for the Evergreen Volunteer Fire Department;

* Deferred for public comment a proposal that would abolish a law requiring county teachers to be tested periodically for tuberculosis.

* Expressed opposition to a proposed state law that would put restrictions on the bonds counties offer to businesses as an encouragement to settle in their area;

* Appropriated $25,000 from an emergency fund to the Hammill Mill Park for the rehabilitation of an unused pool;

* Learned that Manassas has agreed to pay $1.9 million, or 20 percent, of the total cost of building and furnishing the new Prince William County/Manassas Courthouse, almost completed.