World Nuclear News stated that Leningrad 1, the oldest operating RBMK unit, has been reconnected to the grid after the completion of work to resolve deformation of its graphite moderator.
This 38 year old reactorof 915 MW capacity has been in the news for some time
Unit 4 of the Chernobyl reactor which got severely damaged in 1986 was an RBMK reactor. These reactors use graphite as moderator. After the accident at the Chernobyl reactor, Russians have modified many features of the surviving fleet to enhance their safety. The fate of Leningrad 1 was under speculation for the past few months. Please see the following link.
Currently, Russia operates 11 RBMKs. WNN noted that four first-generation units, Leningrad 1 and 2 and Kursk 1 and 2, have been operating since the 1970s. Leningrad 3 and 4, Kursk 3 and 4 and Smolensk 1 and 2 are second-generation units and all started up in the 1980s. Smolensk unit 3, which started up in 1990, was completed to third-generation standards.
WNN stated that Similar work will be carried out at the remaining RBMKs.