The contractor building Phase 2 of the Silver Line has identified another problem with the beleaguered project. This time it’s at the Dulles Airport station, where concrete pedestals designed to support the two-story structure’s glass walls and windscreens are cracking because they were built without proper internal reinforcement.

The pedestals, which sit atop 20 concrete columns, are critical because they serve a dual purpose: They help anchor the glass walls on the station’s first level, as well as the glass windscreens that will be installed on its second level.

This latest development adds to a lengthy list of problems the contractor, Capital Rail Constructors, must resolve before it can complete work on the $5.8 billion project. CRC was expected to wrap up its work in August, but the company said it is unlikely it will make that deadline.

In its most recent monthly progress report, CRC told the Metropolitan Washington Airports Authority, which is managing the project, that it expects to finish its work in February. The project is already 13 months behind schedule.

Once complete, MWAA will turn the project over to Metro, which will manage and operate the rail line. The first phase of the project, which included five stations, opened in 2014.

“CRC continues to evaluate the project to identify opportunities to improve the schedule and to minimize impact of unforeseen changes,” company officials said in a statement.

Under its agreement with the airports authority, CRC, a joint venture between Bethesda-based Clark Construction Group and Kiewit Infrastructure, would face financial penalties starting in October for failing to complete the project by August.

Meanwhile, the company is still trying to find an acceptable fix for a problem that surfaced in September when a review found that more than 400 concrete rail ties failed to meet project standards.

Keith Couch, project director for CRC, played down the problems at the Dulles station, saying that officials are working to find a solution. He said the fact that the problems were discovered before the project was completed is a sign that the company’s quality control program is working. CRC’s inspections and quality control have come under criticism as the project’s problems have mounted.

Project executive director Charles Stark characterized the issues at the Dulles station as a “workmanship problem.”

CRC, which designed and built the pedestals, will be responsible for paying for whatever repairs are ultimately decided on.

Cracks in the concrete pedestals were discovered in April 2018, but it wasn’t until November, when CRC began to remove the concrete to make repairs, that the extent of the problem was discovered, Stark said.

Crews found that the pedestals were not properly reinforced, leaving them vulnerable to cracking. Studs designed to secure the steel plates that would sit on top of the pedestals were bent.

A letter sent to CRC by the airports authority in December characterized the issues as “significantly more serious than initially thought.”

Documents obtained by The Washington Post through a public records request include a root cause analysis prepared by CRC, which determined both the design and instructions workers received in the field were confusing.

“The root cause analysis performed by our quality control team identified multiple contributing factors, including field installation and design details that were misinterpreted,” Couch said.

The analysis also recommended the project’s engineer of record and quality inspectors provide more oversight when construction involves “critical connections” between project elements, as was the case with the structures that included the pedestals.

CRC officials said they are working with MWAA and Metro on a possible solution.

“We are aware of the situation and monitoring progress as MWAA and the contractor work to resolve the issue,” Metro said in a statement.

The Silver Line is the first extension of the Metro system that is not being built by the transit agency. Instead, the work is being done by a private contractor hired by the airports authority.

The rail line’s second phase includes six stations and will provide direct Metro service for travelers headed to Dulles International Airport. Travelers wanting to take Metro to the airport now can take the Silver Line as far as Wiehle-Reston East station and then take a bus or other mode of transportation the remainder of the way. Phase 2 will also extend Metro into eastern Loudoun County.

CRC also remains at odds with MWAA and Metro over how to deal with hundreds of flawed concrete rail ties installed at crossovers, where trains move from one track to another. The ties are higher in the middle than on the ends, which is problematic because they can cause trains to lean when they move over those areas.

CRC proposed at least two solutions, both of which included the use of shims to even out the tracks. Both were rejected by MWAA and Metro.

In a letter sent to CRC last month, Metro officials wrote that the company’s proposed remedies were “unacceptable” and “will result in increased maintenance costs, increased maintenance cycles and a reduction in the useful life cycle of trackwork components, all of which is not acceptable to [the Washington Metropolitan Area Transit Authority].”

However, the airports authority, which commissioned its own review of the concrete ties, said its analysis indicates that while some of the ties are problematic, the number of flawed ties could be far fewer than originally thought, according to Stark, the project’s executive director.

Even before the latest problems surfaced, CRC was already under scrutiny for its quality control in the wake of a whistleblower lawsuit that said a subcontractor had fabricated reports about the quality of the concrete panels it provided for the project.

The panels were used to construct the exterior walls at five of the six stations being built as part of Phase 2. (The panels were not installed at the Dulles Airport station; those panels were manufactured by a different contractor.) One person, the nephew of the company’s owner, pleaded guilty in connection with the suit. The company, Pennsylvania-based Universal Concrete, and its president and co-owner, Donald Faust Jr., reached a million-dollar settlement with the U.S. Justice Department and the state of Virginia but admitted no wrongdoing.

As a result, CRC agreed to treat the panels with a special sealant to ensure they don’t deteriorate.

The first phase of the Silver Line opened in July 2014, seven months late and more than $150 million over budget. It included five stations — four in Tysons and one in Reston. Although ridership on the line has not met expectations, Virginia officials maintain that it is an important catalyst for development in Tysons and the Dulles Corridor.