The site was reported to the Arizona State Museum in September 1951 by Marc Navarrete, a local resident, after his father found two Clovis points in Greenbush Draw (eroded by the Greenbush Creek, a tributary of the San Pedro river), while digging out the fossil bones of a mammoth.
[2][3][4][5] In only five days, Haury recovered the remains of a Columbian Mammoth in association with 8 Clovis points (including the 2 originally found by the Navarettes).
[6][7] The Naco site was the first Clovis mammoth kill association to be identified in Arizona.
[5] An additional, unpublished, second excavation occurred in 1953 which doubled the area of the original work and found bones from a 2nd mammoth.
In 2020, small charcoal fragments were found adhered to a mammoth bone from the site.