New, long-awaited subway stations along the MTA's Second Avenue line are at risk of missing their promised December 2016 opening due to delays in critical equipment testing and the installation of communication systems, according to an independent engineer hired by the MTA to monitor the project's progress.

"Looking at the schedule based on the project's reports and our own field observations of the station construction program, we find that the project is not on schedule and has fallen further behind schedule in the month since our last report to you in June," engineer Kent Haggas, who has been skeptical of the December deadline for months, told the MTA's board on Monday.

Haggas added that the MTA needs to implement a "revised schedule" if it hopes to finish on time, a suggestion that MTA Chairman Tom Prendergast, presiding over Monday's meeting, did not comment on.

The MTA did not respond to a request for comment on construction progress.

Haggas added that of a total 608 system tests scheduled through the end of June along the new line, only 336, or 55%, were completed by the end of last month.

Anil Parikh of the MTA's Capital Construction Company also alluded to delays, but said he didn't believe they would impact the December deadline. At the new 72nd Street, 86th Street, and 96th Street stations, he said, contractors are behind on installing communication systems because of "the incomplete conduit installation by the station contractors." (Conduits being the tubes that protect electrical wiring.) In order to speed up the process, contractors are working double shifts.

"So let me get this straight," said MTA Board member Mitchell Pally, after Parikh's presentation. "The station contractor did not do his job."

"That is correct," Parikh said.

"As a result of that, we've told the systems contractor, who comes in after the station contractor, to do the job that the station contractor did not do," Pally said. Parikh confirmed this.

At this point, Prendergast chimed in. "There's no question about the competency of the systems contractor," he said. "We're just adding to his work. It's the better [option]... if we're all aimed at getting this done on time."

The MTA has said that the Second Avenue line will serve a daily ridership of 200,000 New Yorkers, relieving congestion on the 4, 5, and 6 trains. The Q train will reroute along its length, necessitating the return of the W train to serve Astoria. The authority has also promised to fast-track further Second Avenue stations on up into East Harlem, at 106th, 116th, and 125th Street.