AUGUSTA — Gov. Janet Mills on Friday vetoed a bill that would have imposed a temporary ban on data centers.

For weeks, Mills, a Democrat running for the U.S. Senate, said publicly that she wanted the legislation to exempt a project in the works at the former Androscoggin Mill in Jay.

But the version that passed the House and Senate did not include that exemption.

“A moratorium is appropriate given the impacts of massive data centers in other states on the environment and on electricity rates,” Mills wrote in her veto letter to lawmakers. “But the final version of this bill fails to allow for a specific project in the Town of Jay that enjoys strong local support from its host community and region.”

Mills said in the letter that she will issue an executive order that calls for the establishment of a council to study the impact of data centers. That was part of LD 307, the bill she vetoed. 

The bill sought to place a moratorium on data centers until November 2027.

In March, Jay town leaders wrote to Mills urging her to veto the bill or demand an exemption.

The current data center proposal for Jay is described as a “small scale” project that will use the existing electrical grid and will tap into less than 1% of the water that had been used by the mill.

The $550 million investment is projected to generate 800 to 1,000 jobs during construction and 125-150 “high paying jobs” once it’s up and running.

According to her office, Mills did sign a related data center bill that prohibits data center projects from getting certain types of tax breaks.

She issued one additional veto on Friday. She vetoed LD 1911, which automatically seals criminal history record information for certain crimes.

Lawmakers will be back in session Wednesday to consider Mills’ vetoes.