Metro officials took control of the Silver Line on Tuesday, saying they have “a high level of confidence” they’ll be able to complete the necessary testing and training in time for a summer opening.

“Obviously, we’re very pleased,” said Metro Deputy General Manger Rob Troup. “We would not have reached this [point] if we were not confident of being able to do the testing within the time frame.’’

Troup said officials have set an aggressive schedule for ensuring Metro personnel and others are familiar with the ins and outs of the first phase of the $5.6 billion rail line before it begins carrying passengers. Under the transit agency’s agreement with the Metropolitan Washington Airports Authority (MWAA), which is overseeing construction of the line, Metro has 90 days to complete all its work. But because some testing and training have already occurred, some officials believe Metro will not need the full three months.

The handover was finalized with the signing of a two-page document between Metro and MWAA.

Barring any major problems, this means service could start in late July or early August.

Still, Troup was careful to tamp down expectations and cautioned that issues could emerge that could delay the opening. Specifically, Dulles Transit Partners (DTP), the Bechtel-led contractor building the first phase of the rail line, still has work to complete before passenger service can begin. A special agreement between Metro and MWAA allowed the project to be handed over even though DTP was still finishing its work.

“Should DTP not perform — then there may be issues with the opening date,” Troup said. “We’re tracking that very closely.”

Without that agreement in place, Metro General Manager Richard Sarles has said, passenger service could have been delayed until later this year.

This first phase, with a price tag of about $2.9 billion, will have five stops — four in Tysons Corner and one in Reston at Wiehle Avenue. Preliminary work on a second phase, which will have six stops, including one at Dulles International Airport, began this year. It is expected to be completed in 2018.

Tuesday’s handover also means that federal officials as well as officials from the Tri-State Oversight Committee (TOC), the independent safety organization that monitors Metro’s operations, can begin their own testing. Troup said Tuesday that TOC officials had already begun preliminary work.

“The Federal Transit Administration’s number one priority is the safety of the riding public,” said Therese McMillan, deputy federal transit administrator. “We will do our due diligence to ensure that the Silver Line has met all safety and readiness requirements before beginning service, and we will continue to work closely with the Tri-State Oversight Committee to ensure the line is ready for safe and secure operations.”

As part of its review, the Federal Transit Administration will ensure that MWAA and Metro have completed required testing of rail cars, track infrastructure and related equipment. They also will ensure that Metro has met all safety and security certification requirements. The agency also must be confident that Metro has the “capacity and capability to operate the new line.”

Klara Baryshev, who chairs the TOC said that she did not anticipate any problems but that the committee’s review would be thorough.

“We don’t expect to find anything critical — anything that is a show­stopper, but we’ll see,” Baryshev said.

Tuesday’s handover is a major step forward for a project that has been beset by delays and cost overruns. Dulles Transit Partners was nearly seven months late delivering the project. And even with the handover, there are still operational issues.

In April, project officials conceded that after months of trying, problems with the line’s signaling system could not be resolved and that it would cost $1.8 million for a solution that would take up to a year to complete. This is the first full line to be added to the Metro system in more than two decades. It also is the first that was not built by Metro.

Officials had originally hoped to open the Silver Line in December 2013.

As part of Metro’s preparations, Metro Transit Police Chief Ronald Pavlik said his department will coordinate with law enforcement authorities from other jurisdictions, including MWAA and Fairfax County, on joint exercises designed to familiarize first responders with the system. The first is expected to take place this weekend.

A second, larger exercise will involve rescues from one of the aerial platforms near the Spring Hill Station in Tysons Corner. The drills will be conducted on the weekend during off-hours to lessen disruption.

In addition, Pavlik said about 800 first responders have taken part in training designed to familiarize themselves with the Silver Line.

Troup said that leading up to the Silver Line’s opening, officials will conduct a week of simulated service with the goal of integrating the new rail line into the existing system.

Get updates on your area delivered via e-mail