The 130-foot height of the new 12-story Metropolitan Square office complex poses a potentially "serious" threat to White House security, according to the Secret Service, whose concern over the risk was never communicated to the D.C. City Council when it approved the higher elevation in 1979.

Mayor Marion Barry signed into law Nov. 2, 1979, the measure allowing developer Oliver T. Carr to increase the height, although Barry had been sent a copy of a letter outlining the concerns of the Secret Service two weeks earlier.

Approval of the height increase was part of a 1979 deal between the city government and Carr, in which the city agreed to support Carr's plan for the $70 million complex, including the height change, in exchange for the prominent developer's commitment to preserve the historic facades of the Keith Theatre-Albee building and the National Metropolitan Bank site on 15th Street NW.

Advertisements for Carr's recently completed complex at 15th and G streets NW tout "an unobstructed view of the White House." The rooftop vantage point, topped by an equipment house containing machinery, which raises the total elevation to 148 feet, affords a commanding view of the north side of the presidential residence.

Several months ago, as the building neared completion, the White House stopped the customary practice of having President Reagan greet visiting heads of state at the North Portico for state dinners. Instead, the first family received the visitors inside.

Recently, the White House resumed the North Portico greetings, but used a large portable white screen to block the view from the Metropolitan Square site.

The 130-foot elevation, across the street from the Treasury Department, is considerably higher than most 15th Street buildings near Treasury, which were limited to 95 feet by a 1910 law that the council amended slightly to allow Carr's requested height.

The Secret Service declined to discuss the new security measures, but a well-placed White House official said in an interview that the new building has prompted "great concern." The official, who asked not to be identified, said: "I personally don't think we are doing a very good job on this. We don't yet have the situation under control."

The concern about White House security is heightened by the planned second-phase development of Metropolitan Square, which has been approved for eight feet higher than the first phase and which allows a view of the South Portico.

While there are other buildings in the area that have clear views into the White House grounds, many are government-owned and already have security systems. The Secret Service has no control over privately owned buildings.

"We still have the same concerns" as in 1979, said Jack Smith, deputy assistant director of the Secret Service, "and they are becoming more paramount with the issue of the second building" at Metropolitan Square. "We are pursuing this thing through appropriate channels," Smith said. He would not elaborate.

The Secret Service "followed through and took appropriate steps in communicating our objections, and apparently it got misplaced, or something, I don't know," Smith said.

"I never knew anything about the security concern," said City Council member John A. Wilson (D-Ward 2), who introduced the bill on behalf of the Oliver T. Carr Co. to enable the increased height. "I am quite sure it would have been a different decision" if the council had known the Secret Service position, he said.

Wilson faulted Barry for failing to raise the issue. "The mayor makes comments on legislation while it is in committee. They should have told us about this major difficulty," Wilson said.

Barry's office, however, was not officially informed of the Secret Service concern until Oct. 18, a week after the council acted by making a 14-word insertion in the 1910 law. Two weeks later Barry signed the measure into law. The Secret Service position was outlined in an Oct. 10, 1979, letter to the federal National Capital Planning Commission (NCPC) from John R. Simpson, assistant director of the Secret Service for protective operations. Simpson said that Carr's plan had been "thoroughly studied" by the Presidential Protective Division and Uniformed Division of the agency, and wrote:

"It is the unanimous opinion of both divisions and this office that any proposal which raises the current height limits on buildings near the White House would adversely affect the overall security of the White House Complex, and seriously interfere with our ability to provide protection for the President and his family.

"In the event that favorable consideration is given to any of the Carr Company proposals, a situation would be created where a privately owned and operated office complex would have an unobstructed view onto the White House grounds, and this would present an uncontrollable situation from a security standpoint."

He added: "Approval of the Carr Company proposal will represent a serious invasion of privacy to the President and his family. Obviously, any construction which would afford a view onto the South Grounds is, in effect, building a platform over the President's backyard."

Simpson's letter was sent to NCPC executive director Reginald W. Griffith, who sent a copy to Barry on Oct. 18, 1979, with an attached letter saying, "In light of this security concern, we would be pleased to suggest alternative height and set-back modifications which may be more acceptable in this area overlooking the White House."

Barry's spokesman, Annette Samuels, said that the mayor's representative on NCPC, former assistant city administrator James Gibson, was told of the Secret Service letter. Gibson, she said, discussed the issue with NCPC staff and other officials "and determined it was an issue that didn't need to go beyond that point."

Gibson, in an interview, said he recalled discussing the problem with officials from the Treasury Department and the White House. Gibson said he pointed out to them that other buildings near the White House were already roughly the same height as the new one.

"It was not something that was swept under the rug. It was discussed . . . but it was not concluded to be a new security question," he said.

Gibson said he did not recall how the issue was finally resolved. "I think I assumed that the NCPC met on it, but I hear now that they did not," he said.

Two former NCPC members, Nelson Rimensnyder and Margaret Crenshaw, who represented the House and Senate respectively on NCPC, said in interviews this week that they were never informed of the Secret Service position and they said NCPC would have taken steps to publicize and resolve the issue if the members had been told.

NCPC director Griffith said in an interview that he did not inform other NCPC members of the Secret Service letter, partly because NCPC did not actually have jurisdiction over approving or denying the height. NCPC is authorized to represent "the federal interest" in such matters and could have brought it to the attention of the City Council or other agencies, NCPC members said.

Griffith said he also kept the matter secret because the Secret Service, in earlier discussions of the issue, had asked him to keep "a low profile" on the security issue.

In addition, Griffith said he also did not want to raise the Secret Service issue with NCPC chairman David M. Childs because to do so would possibly create "accusations of conflict of interest."

Childs, who was the presidentially appointed chairman of NCPC from 1976 to 1980, was also Carr's design architect on the Metropolitan Square project. Because of the dual role and its potential for conflict, Childs said, he excused himself from any NCPC deliberations on the project.

Childs, in an interview, said the security question never occurred to him because of the other buildings of comparable height on the east and west sides of the White House. Childs said he appeared as Carr's architect before other governmental agencies considering the Metropolitan Square building, but he said the security concern never surfaced.

Arthur P. Hanket, a spokesman for the Carr firm, said the Secret Service inspected the building and set up security measures during President Reagan's inaugural motorcade, but added that the Secret Service had not voiced their concerns directly to the company.