In 1969 and 1970, Robert Smithson created three “pour” sculptures that demonstrated his mastery of a difficult and deadly medium: entropy. In all three, an industrial material was prepared and poured downhill at a remote or neglected site and left to solidify. The first of these sculptures, Asphalt Rundown, was a dramatic release of hot, viscous black material down the shorn crags of the defunct quarry, intended—and perceived—as a “powerful, annihilating gesture,” in the words of Frank Stella.1

It was early in December 1969, while still in negotiations with the government of British Columbia over securing the Miami Islet site for his Island of Broken Glass proposal1 , when Smithson visited the Anaconda Copper Mine at Britannia Beach (just north of the city of Vancouver, British Columbia). What came out of that visit was a series of drawings that included Spill: Fluvial Discharge (Britannia Beach Project).