After the massacre, the town's newspaper noted, "Nothing but heaps of smoking ruins mark the spot where Chinatown stood."

The town of Rock Springs sprouts out of a vacant landscape of sandstone cliffs and sagebrush in southern Wyoming. It is a fading former mining town, where herds of deer now meander through the streets. A century-old sign overlooking the railroad tracks downtown reads “HOME OF ROCK SPRINGS COAL.” The mines closed decades ago. In the late nineteen-eighties, workers began filling the honeycomb of underground tunnels beneath the town with a cement-like grout, to prevent cave-ins. Ominous crevasses–evidence of “subsidence,” in geological parlance–recently opened in a one-acre park situated between a Catholic church and a former Slovenian community hall. State officials concluded that more grout should be injected. But, before that happens, there’s another pressing need: understanding what else lies beneath the surface.

On a chilly morning this past July, a small group bearing shovels, trowels, brushes, and other tools gathered in the park and began digging into the topsoil. In the course of several days, they excavated a series of neat squares, eventually carving out a chamber about a metre deep. They removed the dirt with buckets and poured it onto rectangular screens to be sifted. Curious neighbors wandered by.