A specially convened session of the Arlington grand jury this week indicted 58 adults and six juveniles on felony drug distribution charges, the result of a major effort by Arlington police to clean up the county's largest street drug center.

The indictments follow an eight-month undercover investigation of the Green Valley section of the Nauck neighborhood in south Arlington, according to Lt. John Karinshak, head of the police department's Vice Control Section. The investigation also included the Buckingham community at North Glebe Road and North Pershing Drive and the nearby Hall's Hill area, Karinshak said.

Karinshak said 15 arrests have been made since the indictments were handed up Monday evening. He said additional, related indictments will be brought before the regular meetings of the grand jury Monday and in August.

"They cleaned up, didn't they," said Joan Cooper, a Nauck resident who works as a liaison between neighborhood residents and the police department. "The community has been very much concerned about the issue."

Trials will be set within 90 days, said Commonwealth's Attorney Helen F. Fahey.

Sixty-one of the total 92 indictments were for distribution of cocaine, 28 for PCP distribution, one for marijuana and two for conspiracy to distribute drugs. Karinshak said most of those indicted are alleged to be street-level dealers who sell drugs by the gram.

The investigation, which is ongoing, involved one undercover officer and four narcotics investigators. "He would hang out on the street corner," Karinshak said of the undercover officer. "He had absolutely no problem buying {narcotics}."

This week's set of indictments follows a similar undercover sweep by the department's tactical unit in April. At that time, 26 persons were arrested on drug distribution or possession charges. One week after those arrests, an undercover officer returned to the area and made 17 arrests for possession of PCP in one night, police said at the time.

In May, the police department used its special weapons and tactics team for the first time in more than a year in what it anticipated would be the arrest of some of Green Valley's major cocaine suppliers. However, only two alleged mid-level dealers were arrested during the raid, police said.

The drug sweeps are the byproduct of a close working relationship, developed over several years, between the police department and the Nauck community, police and community activists said yesterday.

"The community is really fed up," said John Robinson, director of the community's Martin Luther King Community Center. "If somebody doesn't take a stand, you wouldn't be able to walk out of your house."

The Nauck community is a predominantly black, middle-class family neighborhood that dates to 1866. It is home to one of the county's most successful magnet schools, the Drew Model School.

But the Green Valley section of Nauck is also the only area in the county in which street-level drug trafficking is commonplace, Karinshak said. He said most of the activity takes place within a block of South 24th Street and Shirlington Road, where young men and women congregate at a popular local bar and teen-agers can be seen late at night milling around the parking lot of a nearby convenience store.

Increasingly, the community has rebelled against the trade that has developed there.

"We had a lot of tips and informants calling in," Karinshak said. "We had people coming in to talk, calling in, or we'd go out for a visit. There's a strong sense of community involvement."