WASHINGTON (Map, News) - The Northern Virginia Transportation Authority approved refunding at least $11.7 million in unconstitutional taxes and fees Thursday, beginning a major logistical effort that will stress its small staff and limited budget.

Authority members unanimously approved the measure without adopting a clear plan for distributing the money, which is expected to take weeks to develop.

“How well the refund process is executed will have a significant impact on NVTA’s credibility,” Executive Director John Mason wrote in a memo. “Importantly, it could have further impact on the confidence of the public and elected officials in going forward with future revenue mechanisms.”

Taxpayers have been asked to keep track of their receipts for the 63-day life of a plan that would have raised about $300 million annually.

The refund process could be led by the state or the NVTA, and the full logistics have not been worked out.

Complications already identified include operating a Web site for people to request refunds and tracking down any visitors who rented cars or stayed in hotels between Jan. 1 and March 3.

Communicating with the authority’s hundreds of tax collectors and reviewing thousands of transactions will complicate the process, as will locating people who sold property and left the region.

No reliable cost estimate has been conducted, but Mason’s memo said it is probable the price tag will climb into the hundreds of thousands of dollars.

That could wipe out the $1 million starting budget of the agency and force the state to pony up more money to reimburse the taxes, authority members said.

dgenz@dcexaminer.com