An international effort to seal the destroyed remains of the nuclear reactor that exploded in Ukraine 30 years ago is finally close to completion, and remarkably, considering the political revolution and armed conflict that have rocked the country since 2014, it’s close to being on schedule.

The completion of the New Safe Confinement, often called the “arch,” could contain the radiation from mankind’s worst nuclear catastrophe for a century, says the European Bank for Reconstruction and Development, which has led the project. But it will also mark a handover to Ukraine’s fractious and underfunded authorities, who are expected to tackle future waste management at their own expense.