A Nuclear Regulatory Commission investigation has concluded Exelon Nuclear provided NRC with inaccurate information about how much money will be available to de-commission the company’s power plants at the end of their lives, potentially hiding a shortfall of “roughly $1 billion.”

In a Jan. 31 letter to Michael Pacilio, President and Chief Nuclear Officer of Exelon Nuclear, the NRC wrote that its “investigation did substantiate that a senior Exelon executive and an Exelon manager appear to have deliberately provided incomplete and inaccurate information to the NRC” regarding de-commissioning funds at 23 nuclear reactors at all 12 plants in the Exelon nuclear fleet, including the Limerick Generating Station.

In addition to Limerick, shortfalls were also identified at other two other Pennsylvania, plants — Peach Bottom and Three Mile Island — and two New Jersey power plants — Salem and Oyster Creek — as well as seven nuclear plants in Illinois.