Comptroller General David Walker told Senate appropriators on Tuesday that “risks and uncertainties” in the construction of the Capitol Visitor Center could drive the project’s final price tag to $559 million, more than twice its original estimate.

In testimony before the Appropriations subcommittee on the legislative branch, Walker, who heads the Government Accountability Office, also stated that the 588,000-square-foot project is unlikely to be finished before December 2006, three months after the target date backed by the Architect of the Capitol, and nearly two years behind the original schedule.

“We think it’s more realistic for the base project to be done in December ’06 to March ’07,” Walker said in reference to the visitor center itself, as well as exhibits, technical security, improvements to the East Front plaza, and a tunnel connecting the CVC to the Library of Congress. “We’re not quite as optimistic as the Architect of the Capitol based on past experience.”

In his skepticism of the fall 2006 opening date, Walker stressed that the AOC has not provided to GAO a definition of “complete,” and he asserted that the center may open with many “temporary” measures, including security features.

Architect of the Capitol officials defended the project, however, stating that the visitor center will be ready on its current schedule.

“The whole visitor experience … will be ready in September,” asserted Architect of the Capitol Alan Hantman. He later added: “It’s a tight schedule, but it’s a doable schedule.”

CVC Project Executive Box Hixon echoed the Architect’s sentiment, stating: “At this point, based on everything we are aware of, this is entirely realistic.”

The Architect did acknowledge, however, that House and Senate expansion spaces flanking each end of the visitor center are now slated for completion in March 2007.

The AOC awarded contracts for both areas, which total 170,000 square feet, on Monday.

The Architect’s office also awarded a contract earlier this month to complete exhibition space in the visitor center, but Hantman said that area should be finished along with the main section.

The legislative branch officials also differed over current cost estimates for the visitor center, for which the Architect’s office has requested another $36.9 million in its fiscal 2006 budget. (GAO recommended that Senate appropriators include an additional $5 million over that amount, calling the new funds insufficient.)

Although current AOC estimates put the CVC’s price tag at $517 million, Walker stated in his written testimony that an additional $44 million may be needed to address “unforeseen conditions, scope gaps and changes, and possible further delays.”

According to GAO estimates, Walker said the cost is now expected to reach between $522 million and $559 million, “significantly more than originally estimated.” When Congressional leaders broke ground on the project in 2000, its budget stood at $265 million.

“The majority of delays and cost increases were largely outside the AOC’s control, but weaknesses in AOC’s schedule and contract management contributed to a portion of the delays and cost overruns,” Walker testified.

Among the increases, Walker said, are $147 million in “scope changes,” which include major project alterations, such as Congress’ decision to complete House and Senate expansion space along with the visitor center. Lawmakers appropriated an additional $70 million for the project following the Sept. 11, 2001, terrorist attacks.

While another $45 million in increases can be attributed to such factors as higher-than-expected contract costs, Walker said, about $58 million in cost overruns were the result of factors such as delays in the project that could have been controlled by the Architect.

During the hearing, ranking member Dick Durbin (D-Ill.) also raised concerns over workplace safety on the CVC construction site.

“This appears to be one of the most dangerous work sites in Washington,” Durbin said, citing injury and illness statistics from 2003 and 2004.

According to worker safety data provided by GAO, the injury and illness rate for employees on the site are about 50 percent higher than for comparable construction sites in 2003, and even higher in 2004.

AOC officials asserted that the majority of the injuries were attributed to the Centex Construction Company, which had been contracted to complete the first phase of the visitor center, including excavation and structural work.

Hixon asserted that Centex provided inaccurate information to the Gilbane Building Company, a construction management firm overseeing the project that is also responsible for monthly safety reports.

“We were not aware that the situation was as bad as it has been,” Hixon testified.

According to GAO, the monthly reports underreported “lost-time” incidents in 2004, tallying only three such incidents when a GAO analysis found 45 occurrences.

“The construction management contractor attributed the inaccuracies to key data missing from its calculations, unawareness of [an Occupational Safety and Health Administration] formula change that began in 2002, mathematical errors, and poor communication with the major construction contractors,” Walker’s written testimony states.

Among the major problems, Hixon testified, is protecting workers from falls. GAO officials confirmed after the hearing that inadequate “fall protection” ranked among the top safety violations during the period covering January 2004 to October 2004. Bruising and lacerations were listed as the most common injury over a two-year period, although without additional analysis it is not clear whether those injuries could have resulted from the safety violations, the officials said.

“Because the number of construction workers at the CVC site is soon expected to increase significantly, worker safety will continue to be an important issue during the remainder of the project,” Walker stated in his written testimony.

CVC officials have previously said the number of workers assigned to the site will increase from about 250 to more than 600, including skilled electricians, painters and pipe fitters.

The Tuesday hearing marked the first in a series of monthly reviews of the visitor center, as Sen. Wayne Allard (R-Colo.), seeks to improve oversight of the project.

The subcommittee will meet again next month, Allard said, in an attempt to “help keep ourselves informed” on the visitor center’s progress.