Officials in King George County, Va., voted early this morning to revoke a permit that would have allowed building of a plant in the rural Virginia county to dispose of sludge produced in the District of Columbia.

Officials of Dano Resource Recovery Inc., had said they planned to build the plant to convert sludge from the Blue Plains seqage treatment plant into compost under a $20 million, five-year contract signed with the city this week.

The city has been disposing of sludge, the tesidue of sewage treatment, by burying it at suburban sites. Recently, however, as possible sites have been exhausted, the city has come under federal court pressure to find other means of disposal The Dano contract was seen as one such means.

When reached by telephone early today, both Dano and city officials said they had not been informed yet of the building permit revocation vote by the King George supervisors.

"We haven't heard anything about it," a Dano executive said

Florence Tate, Mayor Marion Barry's press secretary, said she could have no comment until she received more information.

In a telephone interview early today, Reginald Hayden, chairman of the three-member board of supervisors, said an investigation indicated that plants submitted to two other agencies differed from plans submitted to county authorities.

The "indication is [that there are] three sets of [soil and erosion] plans" for the proposed King George County site, Hayden said.

"We don't know if we have the real plan or not," he added. "Until we do, we have requested the license to the revoked."

Hayden said the investigation came after considerable information was submitted by environmental groups to officials of the rural county on the Potomac River about 40 miles south of Washington. The county's population is about 9,000.

He said Dano would be notified today of the board's action.

Henry Valentino, a Dano executive, and "We submitted the plans in accordance with the county regulations."

Without having spoken directly to the supervisors about their reported objections, he said: "I don't know what they're talking about."

The contract signed this week called for daily shipment to King George by closed barge of about 800 tons of sludge, about 250 more than now is produced at Blue Plains by processing of the city's own sewage. Suburban sewage also is treated at Blue Plains.