A New York firm that tried and failed earlier this year to work out a deal to ship District of Columbia sewage sludge to Haiti for use as fertilizer is now trying to arrange to ship the material to the small Caribbean island of Antigua.

"All they did is switch islands," said William B. Johnson, acting director of the D.c. Department of Environmental Services, of the plan currently being negotiated by Stewart Environmental Systems Inc.

Johnson said the city favors the plan as the most promising of about two dozen proposals submitted for disposal of most the estimated 2,200 tons of sludge that will eventually be produced each day at the Blue Plains sewage treatment plant in far Southwest Washington.

Bernard D. VanKleeck III, president of the Stewart firm, said in a telephone interview yesterday that the treated sludge would be odorless and free of dangerous bacteria when it arrived on Antigua's shores.

He said the firm had received from the Antiguan government a letter expressing interestin the project, which would allow the Stewart firm to build a plant to convert the sludge into fertilizer and then lease land for agricultural projects.

However, Lester Bird, vice premier of Antigua -- which is a semi- independent protectorate of Great Britain -- left a meeting of the island's parliament yesterday afternoon to relay work through a spokesman in New York that the deal is not yet final.

"he [Bird] said that we are looking at the proposal but there are no signed agreements," Lloyd Jacobs of the Antigua Department of Tourism and Trade told a reporter after reaching Bird by telephone in Antigua. "the cabinet has not yet acted," Jacobs said.

VanKleeck said that politically active D.C. attorney Robert B. Washington Jr., chairman of the Democratic State Committee, has been involved on behalf of the Stewart firm in the negotiations with Antigua. Washington declined to comment. Also involved, Vankleeck said, is former senator Joseph Tydings, a member of the same law firm. Tydings could not be reached for comment.

Johnson emphasized that the city had not yet signed a contract with the Stewart firm. However, he said, the proposal is attractive because it means the sludge would leave the metroplitan area immediately.

Under the plan the sludge would be put on barges at Blue Plains, then trans-shipped to tankers for the cruise down through the Leeward Island to Antigua, a roughly circular chunk of land 10 miles in diameter situated north of Guadeloupe.

Earlier this year the Stewart firm tried to arrange a similar deal to ship the sludge to Haiti. However, the deal fell through because of fears by Haitain officials that the sludge would not be adequately treated.

Potential benefits to any jurisdiction that would accept the sludge would include the opportunity to put barren lands to productive use by using the material as fertilizer, VanKleeck said. He said his firm's operation also would provide more jobs.

Sludge produced at Blue Plains has been a continual source of annoyance for District officials. Currently, in a temporary arrangement, the sludge is placed in trenches in Montgomery and Prince George's counties. But the District is under a federal court orderto find a more permanent way to dispose of it.

Last week the city signed a five-yearcontract with an Alexandria firm, Dano Resource Recovery Inc., to dispose of 900 tons of the sludge a day beginning next year.

But the 900 tons specified in Dano's contract leaves unaccounted for about 500 tons a day being generated by the suburban jurisdictions that also use Blue Plains.