The Synanon Foundation, a drug rehabilitation organization, has told government authorities that it will vacate its proposed East Coast headquarters at the Boston House apartments at 1711 Massachusetts Ave. NW, by June 30, knowledgeable sources have said.

Sources said the organization will leave the District of Columbia and establish East Coast headquarters "several states away." The same sources also said an implicit understanding was reached with law enforcement officials here that warrants will not be served against Synanon founder Charles Dederich and Howard Garfield, another Synanon member, for an alleged assault against a Washington Post photographer.

The sources said that part of the implicit understanding was that neither Dederich nor Garfield would return to the Washington area.

Synanon has been embroiled in a controversy with tenants of the Boston House since May, when Synanon members indicated that they had entered into a tentative agreement to buy Boston House and when Synanon members began to move into the seventh and eighth floors of the apartment building.

"If they really are moving, I feel good about it, but I don't really know what all this means," said Herman Hochman, president of the Boston House Tenants Association.

D.C. police Det. Robert T. Wells confirmed informationnnn gathered from other sources that, during an informal closed hearing Monday at the U.S. a attorney's office, Synanon attorneys said "bad publicity" was one of the reasons why the group is leaving.

Wells also said that part of the reason why Synanon attorneys told law enforcement officials the group would leave the city involved problems in getting the necessary permits to have offices at Boston House despite alleged statements by the building's owner that they would be able to get the permits.

Tenants, aided by their advisory neighborhood commissioner and others familiar with zoning regulations, effectively challlenged Synanon's right to have offices without a permit at Boston House, which is in a predominantly residential area.

Gleason Wilson, supervisor of the Zoning Inspection Branch of the D.C. Department of Housing, said he sent a letter Friday to Stuart A. Bernstein, part owner of Boston House, saying that the use of the building for offices violates D.C. zoning regulations because no certificate of occupancy has been obtained to have offiices there.

Bernstein is the owner of record until such time that Synanon reaches settlement on the property, Wilson said.

Synanon spokesmen and bernstein's lawyer have declined to comment on the case.

At a solidarity rally at the Boston House last week, tenants complained to reporters that Synanon members had harassed them. Several residents said they were afraid that they might be harmed. Residents also said a sign criticizing a tenant who had complained to Synanon was posted in the building's lobby. The sign carried the headiing "funky letter of the week."

Residents complained that Synanon members, who they identified by their shaved heads, had manned the lobby desk and had access to master keys, mailbox keys and the building's secretarial telephone service.

No allegation was made that Synanon members used any of the keys.

Other residents said they were bothered by Synanon members who, in their periodic group sessions in the apartment building's lobby, "made excessive noise."

As the rallly ended, Washington Post photographer Doug Chevalier said he was pushed as he attempted to take pictures of Synanon members and Dederich outside Boston House. Plainclothes police officers broke up the group. Later, the police filed an assault charge that led to Monday's hearing at the U.S. Attorney's office.