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A bout 70 kilometres north of the ancient Chinese capital Xi’an lies a coal belt underneath the rollingmountains. Criss-crossed by a honeycombof tunnels, the belt has helped fuel China’seconomic engine for many years andfilled the c
A bout 70 kilometres north of the ancient Chinese capital Xi’an lies a coal belt underneath the rolling mountains. Criss-crossed by a honeycombof tunnels, the belt has helped fuel China’s economic engine for many years andfilled the c