The District government is responsible for ensuring the safety of all its citizens, but now comes evidence that makes me question whether it can guarantee the safety of its own employes.

According to a recent report by Carl C. Hansen, a consulting engineer commissioned by the D.C. Department of Public Works, concrete beams that support interior walkways in the new Municipal Center at 14th and U streets NW could collapse at any moment without warning, in part because of "gross" design flaws. Calling repairs made by the city inadequate, Hansen said permanent supports are needed to make the walkways safe. About 10 days ago, the city had temporary scaffold-like posts installed to brace the beams.

The problem with the concrete beams supporting a pedestrian walkway on the third through sixth floors surfaced in December 1984, when workers from the Sherman R. Smoot Corp. of Washington, which did the building's concrete work, noticed that, on every floor, the beams had cracked at the corners. Responding to the problem, the city directed VVKR Inc., an Alexandria firm that designed the building, to design reinforcement rods for the beams.

The following July, C.M. Tipnis, a vice president with Smoot, wrote the city that he feared "sudden failure" of the beams despite their reinforcements. However, Richard T. Ball, a VVKR structural engineer, took the opposite position, saying that the reinforced beams could support the building's daily human traffic.

In November, after District employes had already begun to occupy some floors in the building, Horace Jones, a public works official, voiced his department's fears about the safety of the beams. "You are . . . directed to engage the services of a structural engineering firm to design additional support systems for the failed beams," Jones wrote in a letter to McLaughlin Construction Management Inc., hired by the District to provide overall supervision of the project.

But John Touchstone, director of the Public Works Department, later told a reporter that Jones' letter overstates the city's concerns. According to Touchstone, the construction management firm MCM and the design firm VVKR were satisfied "and my engineers are not raising any questions," In other words, he considered the problem largely "solved."

The debate over the safety of the walkways continued between the city, the management firm, the concrete contractor and the design firm. In press interviews, the city and its subcontractors disagreed over whether the problem was a design error or a failure by concrete workers to install a slide-bearing assembly on the sixth floor that would allow the beam to move slightly at the joint. Meanwhile, some 600 District workers continued to occupy the building.

Finally the city decided to seek another opinion from Hansen, the outside consulting engineer. But before Hansen could turn in his report, MCM pronounced the walkways structurally safe. Two weeks ago, Hansen totally disagreed with that view. Noting that the beams' structural designs had not been corrected, he compared the potential dangers of the situation to the disaster in Kansas City almost five years ago when 112 persons died after skywalks collapsed at the Hyatt Regency Hotel. "I'm not trying to be an alarmist, but we just can't afford to have something happen like that ," he said.

Indeed we can't afford such a catastrophe, particularly if it can be avoided. The question that must be asked is whether city engineers thoroughly reviewed the plans in the first place. And why would the city move its employes into a building when alarms had been raised about its safety? These questions must be answered.

One thing that seems clear is that public works officials, opting to hire the construction management company MCM to provide overall supervision of the job, failed to provide strong in-house management to supervise the project. Instead, the agency even stopped its routine, ongoing inspection.

Part of the reason this building was put on a fast track may be that Mayor Marion Barry wanted it to be a visible accomplishment of his administration in an election year. But the hasty occupancy and early concerns about the building's safety may make a lot of District voters stop and think. Although the city says it is now moving to correct the problem permanently, that does not excuse its allowing matters to reach such a crucial point. No reason can justify the city's putting the lives of 600 people in jeopardy.