The activity around the Kashiwazaki-Kariwa nuclear power plant is reaching its peak: workers remove earth to expand the width of a main road, while lorries arrive at its heavily guarded entrance. A long perimeter fence is lined with countless coils of razor wire, and in a layby, a police patrol car monitors visitors to the beach one of the few locations with a clear view of the reactors, framed by a snowy Mount Yoneyama.