The Federal Aviation Administration (FAA) shutdown in July 2011 put 74,000 construction and related-sector workers on payless furlough.
The shutdown, which started on July 23, lasted until Congress reached the deal to extend funding on August 4.
Now, over a week since the workers were brought back and receiving paychecks, they still do not feel secure.
"The most common question I was asked during our town hall was, 'Is this going to happen again?' said Ray LaHood, U.S. Secretary of Transportation, who recently traveled to a town hall meeting at the FAA's William J. Hughes Technical Center in New Jersey.
That's because the August 4 bill only extends funding until September 16, a date FAA paid workers will nervously eye unless Congress comes up with a more permanent solution before then.
"This agreement does not resolve the important differences that still remain," warned Senate Majority Leader Harry Reid when he announced the temporary extension on August 4.
Prior to July 23, Congress extended FAA funding with no strings attached for 20 consecutive times with no hassle and strings attached, according to CBS.
However, in July, Republicans tried to attach additional measures to the funding extension - to change voting rules to weaken unionization and cut subsidies to rural communities - that Democrats objected to.
These fundamentally differences were not resolved on August 4 and threaten to send FAA paid workers home again without pay come September 16.
"I need our employees at work every day and America needs them at work every day," said LaHood.