The National Capital Planning Commission staff has recommended that the commission reject the revised proposal for the controversial Techworld center submitted by International Development Inc. unless IDI agrees to substantially reduce the size of the project and alter its shape.

"The issues raised by the proposed Techworld development are as critical to the character of the Nation's Capital as those of any reviewed during the past several decades," said the staff in its report to the NCPC, which is reviewing the project under its mandate to protect the federal interest in Washington. "If built as proposed, it could establish devastating precedents for future private development throughout the city."

IDI's original proposal for Techworld -- a mixed-use project taking up two city blocks just south of Mount Vernon Square -- included a 950-room hotel, stores, offices and a permanent "trademart" for the high-tech industry.

That proposal was rejected by both the NCPC and the D.C. Zoning Commission last spring. Both groups cited concerns that the project was too big and poorly designed, particularly a proposal for two massive bridges spanning Eighth Street between the two blocks of the project.

Eighth Street, specifically the section that links Mount Vernon Square with Pennsylvania Avenue seven blocks south, is considered by the NCPC, preservationists and others in Washington to be an important element of the original L'Enfant city street pattern. It is part of the only individually designated vista on the national capital's list of historic properties.

The revised proposal from IDI, however, only eliminated one of the spans and reduced the 1.5 million-square-foot project by barely 1,000 square feet. It also retains a request to close Eighth Street to traffic and narrow it from the current 100 feet to roughly 60 feet. As revised, the project would include a 910-room hotel, 1.08 million square feet of space for offices and the trademart, and 53,000 square feet of retail space.

NCPC staff said the proposal, while an improvement over the original, did not address the most serious concerns of either the NCPC or the Zoning Commission. It recommended rejection on the basis that the bridge over Eighth Street would "diminish the landmark vistas" between the Old Central Library in Mount Vernon Square and the National Portrait Gallery, that the proposed building height was not allowed under the D.C. code, and that the scale of Mount Vernon Square would be diminished by the mass of the project.

IDI President Giuseppe Cecchi, in an effort to persuade the NCPC to overrule its staff, defended his proposal at an NCPC meeting Thursday, saying that the six-story span across Eighth Street that would start five stories above ground level was necessary to the success of the high-tech trademart concept, and that the project would bring jobs and revenue to the city.

"The connection over Eighth Street is not necessary to increase the floor space to land area ratio for the project . . . but instead is a functional requirement for the trademart," said Cecchi. He said that the trademart had to be in a continuous space and could not be separated into unconnected buildings, or developers would not be able to attract the quality telecommunications, office automation and computer firms that would make the trademart a reality.

An architectural historian for the Smithsonian, the D.C. Preservation League and the Committee of 100 on the Federal City spoke out against the proposed span and narrowing of Eighth Street, saying that the massive structure would seriously reduce the scope and quality of the historic vista of the street.

"We have grave concerns about the constriction of the street in this proposal and believe it is most inappropriate," said Cynthia Field for the Smithsonian Institution. "We are still unhappy with the fact that the building bridges Eighth Street and believe it is contrary to the L'Enfant plan."

Kim Hoagland, vice president of the D.C. Preservation League, protested the proposed height of the buildings, saying that the top level of 130 feet for part of the project should be lowered to 114 feet.

Under the city's building height law, a developer is allowed to calculate maximum height by taking the width of any of the streets abutting the property and adding 20 feet. IDI used the width of K Street to make its calculation, but it based the total on a wider part of K Street than the section that runs along the property line.

Curtis McClinton, D.C. deputy mayor for economic development, who represented Mayor Marion Barry on the NCPC at the meeting, said that the city's corporation counsel supported IDI's calculation method. NCPC staff, however, said that the allowable height "might have to be decided by the courts."

The commission voted to delay its final vote on the Techworld project until after Thanksgiving. The D.C. Zoning Commission is scheduled to hold hearings on the proposal the week of Nov. 26.