Leif Dormsjo said Wednesday the agency is fully cooperating to get the safety certification necessary to open a long delayed streetcar line.
The D.C. Department of Transportation plans to start simulated streetcar service next month.
The District says it is finished with the warning phase for drivers parked in the streetcars' path.
An operating line would have strengthened case for more funding.
The D.C. Department of Transportation wants to study a streetcar extension to National Harbor.
One potential route would follow old railroad, while another could go through downtown Anacostia.
Long line of applicants seeks to fill 34 jobs with city's new transit system.
The new streetcar is one of six slated to run as part of the new service.
The D.C. Department of Transportation is hosting a job fair for people interested in working with the new streetcar system.
The District plans to move a streetcar to H Street NE on Friday night, then begin testing before passenger service starts in 2014.