Exelon plans to delay decommissioning of its Three Mile Island Nuclear Station reactor Unit 1 (TM-1) for nearly 60 years, with a roughly $1.2 billion cost estimate for that approach.
The reactor will join the long-closed TMI-2 in the long-term storage and monitoring condition known as SAFSTOR, according to Exelon’s April 5 post-shutdown decommissioning activities report (PSDAR) to the U.S Nuclear Regulatory Commission. That “safe storage” approach gives nuclear utilities up to six decades to complete active decommissioning of a reactor, allowing time for radiation levels to drop and funding to increase.
Three Mile Island has two reactors. TMI-1 is owned by Exelon, with its NRC license due to expire in 2034. FirstEnergy Corp.’s TMI-2, closed after famously partly melting down in 1979, has been in a SAFSTOR mode since 1993.
Exelon announced two years ago that it would close TMI-1 in September 2019 — a deadline that remains intact. Its PSDAR calls for initial decommissioning work to be complete by February 2021, and for all of the site’s spent nuclear fuel to be moved to dry storage by December 2022. The used fuel is to eventually be moved to a consolidated fuel storage site — probably in New Mexico or Texas — once one of those sites get built and receive NRC approval.
The reactor would stay in SAFSTOR until resumption of decommissioning in the 2070s, with a 2079 deadline for completion.
Exelon’s budget estimate for decommissioning TMI-1 through that year is $1.001 billion, along with $158 million for spent fuel management and $86 million for site restoration. That brings the total budget estimate to $1.245 billion, according to the PSDAR.
