The granite pavers that make up the Capitol’s East Front Plaza are nondescript and easy to overlook, an expanse of pink stones whose main purpose is to support the wheels of cars and the onslaught of hurried feet.

But this relatively small part of the Capitol Visitor Center construction project has been a constant issue in oversight hearings.

Since the pavers were initially installed in 2004 and 2005, they quickly have chipped and cracked.

Repairs have been slow, with the Architect of the Capitol hiring outside consultants to investigate the problem and then overseeing a multimillion-dollar redesign.

But last week, CVC officials told Members that the plaza should be complete by the end of September.

If successful, the redesign will be one of the last parts of the CVC to be finished. The underground building — an ambitious project that was often criticized for budget overruns and construction delays — opened as the Capitol’s largest-ever expansion on Dec. 2.

Money, however, could be an issue far beyond the replacement of the pavers.

Officials have said in past hearings that the pavers initially cost about $3 million to install — a small percentage of the CVC’s $621 million budget. But the replacement has cost an extra $2.5 million to $4 million, according to testimony at oversight hearings. Officials have said the cost still won’t push the CVC’s total budget to more than $621 million.

The AOC is now in talks with the architectural contractor who designed the plaza and the subcontractor who installed the pavers, attempting to avoid litigation and recoup the cost of the replacement.

In an April 2008 hearing, CVC Project Executive Bernard Ungar outlined the issues involved: “What we had to find out was: What is the cause or what were the causes of the problems that we are having? Are they design-related?Are they installation-related? Or is it a combination thereof?—

AOC and CVC officials declined to answer most questions for this article, citing “ongoing litigation.—

But CVC spokesman Tom Fontana said in an e-mail that the paver installation was “expedited— for President George W. Bush’s 2005 Inauguration.

“While chipping was noted in 2005,— he said, “it was decided that repair work would be completed only after a thorough review of the paver design and installation process and after all major construction work was completed.—

[IMGCAP(1)]Construction crews have been an almost constant part of the CVC landscape since the building’s opening, tearing up the plaza bit by bit. When possible, they reuse the old granite stones, placing them in a new design meant to better withstand the weight of traffic.

The old design — which essentially placed pavers close together — wasn’t ideal for vehicles and caused the pavers to chip and crack, according to a source familiar with the issue. But whether that is the fault of the designers or the construction company is unclear.

“The design set forth how they were to be installed. In [the construction company’s] view, they were following the design,— the source said. “There are some questions about whether they did.—

Complications also arose because much of the plaza is now on top of the CVC, which has wide open spaces and several skylights. Every time a car or truck rolls over the pavers, they move; drainage can also be an issue.

Workers are consequently replacing the pavers that lie on top of the CVC. In a July 2008 hearing, Ungar said the pavers would be put on with a “much more substantive setting bed that will withstand … the more frequent vehicular traffic.—

Most of the plaza is being replaced by this method, though parts of it will remain in the same design, with just the damaged pavers replaced.

The House Appropriations Subcommittee on the Legislative Branch continues to keep an eye on the issue, with Members bringing it up at last week’s CVC oversight hearing.

“The pavers are still a work in progress,’— said Jonathan Beeton, spokesman for Chairwoman Debbie Wasserman Schultz (D-Fla.). “The subcommittee will continue to monitor the last stages of this project to ensure that it meets the high standards which the public should expect in a project of this scope.—

Meanwhile, the underlying issues of why the problem arose in the first place remain unclear. Since the chipping began, AOC officials have asked for the help of numerous consultants, but they have not released the resulting recommendations to the public.

One pavement professional, who described his involvement in the project as “very minimal,— said the AOC’s office contacted him a few months ago. A staffer described the original design and the redesign; both, he said, had “flaws— that could create problems in a few years.

With the redesign already under contract, the AOC was not able to take his recommendations, he said. But he also emphasized that he has never seen the plaza up close.

The number of methods to install pavers is also diverse and numerous, according to Chuck Muehlbauer, technical director at the Marble Institute of America.

Muehlbauer said he was not involved at all with the CVC paver project and did not know any of the details. But he said that installing granite pavers on top of a building — and with the strength to handle vehicular traffic — can “absolutely be done successfully.—

The pavers, he said, have to be “selected, sized, and bedded— to prevent fracture from the stress and also must be able to resist displacement.

“There are a variety of systems proven for this,— he said. “They all come with different budgets and are dependent upon what you have to work with.—