Xu Yanzhou was suspended for eleven days and reassigned to remeasure an old working face outside the Qiling Mine Construction Zone storage area. He cleared out forty-six blast holes and used his feet to map three stages of millisecond delays. He discovered that the design values on the clean copy differed from the site's crumbly surface by nineteen millimeters. Following the empty spot where the third row's fifth hole should have been, he pried apart the rubble and exposed a concrete wall that had no business being there. The faded paint on it still showed the words Third Shaft. Yet the blast sequence numbers for this shaft had never included three-digit codes. He had only eight marks left on his measuring ruler; one more measurement and the label would be gone. Whatever was waiting for him behind the concrete had yet to be revealed.
