The rooms were backfilled with the help of volunteers from the Little Colorado Chapter of the
Arizona Archaeological Society. Part of the restoration process required the volunteers to participate in "mud slinging," a process by which mud is applied to the mortar in the interior walls to maintain the integrity of the rooms. The volunteers also performed maintenance work on the exposed walls which outline the pueblo. On March 10, the backfilling was completed with the application of a clean sandy fill to relieve soil pressure on the walls. The city maintenance crew and archaeology volunteers worked under the supervision and guidance of Doug Gann and Matthew Devitt of the
Center for Desert Archaeology.
The Casa Malpais Site was designated a National Historic Landmark on July 19, 1964. It is significant as one of the few known archaeological sites to include cultural features from both the early and late Mogollon settlement patterns which date from the late Pueblo III to the early Pueblo IV period (A.D. 1250-1325).