The first entry is always the pin's source. Overall confidence is a weighted average of how firmly each reference supports the start and end times used above; a reference counts half as much for every 180 days older than the newest.
Ukraine's Chornobyl NPP states it accepted the New Safe Confinement's Enclosing Perimeter into operation on 8 November 2017 (chnpp.gov.ua[2]).
Chornobyl NPP's own project page states it accepted the NSC's Enclosing Perimeter into operation on 8 November 2017.[1]
The EBRD, which financed the project, confirms the arch was skidded into its final position over 14-29 November 2016.
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