Records of the Ruin Stabilization Unit, 1933-1976 (with gaps. In 1937 Frank Pinkley, Superintendent of the former NPS Southwestern National Monuments, organized a Mobile Ruins Stabilization Unit (Mobile Unit) with a field station in Chaco Canyon National Monument. The unit’s mission was to stabilize and repair the large number of sites in the southwest that were rapidly deteriorating. The unit was set up as a program of the Civilian Conservation Corps (CCC), with a crew of 25 Native American CCC enrollees. The unit was designed to move among the 14 southwestern archaeological and historical monuments, providing emergency and maintenance stabilization. The mobile Unit was disbanded for a time during World War II, then reactivated in 1946. Employees were primarily drawn from the surrounding Navajo reservation, and second and third generation workers spent their careers on a WAE (when actually employed) basis. Early work was concentrated at Chaco Canyon and Aztec Ruin. Standardized record sheets were created in 1937 and maintained throughout the unit’s existence. These forms, together with photographs showing the work done at each site, created stabilization records for each room that was treated. Photographs, recorded observations, experiments, special reports, and job unit reports were created over the years. As work became standardized and techniques improved upon, work expanded to stabilization at other monuments and parks. The Mobile Unit formed the intellectual and empirical basis for NPS preservation method and theory. In 1937 Gordon Vivian became supervisor of the NPS Indian CCC Mobile Unit. After World War II, Vivian returned to head the Mobile Unit from 1947-1958, stationed in Chaco Canyon. By 1956, the Mobile Unit had been renamed the Ruin Stabilization Unit (RSU), managed out of the Southwest Archaeological Center (SWAC) at Globe, AZ. In 1958, he became Supervisory Archeologist for the SWAC, but continued to oversee RSU work. Vivian died of leukemia on April 29, 1966 in Globe, Arizona. When the support office in Globe was moved to Tucson, the RSU program went with it. Until 1976, work at Chaco Canyon was carried out by the RSU program under the auspices of the Division of Cultural Properties Conservation of the Western Archaeological and Conservation Center (WACC) in Tucson. However, by 1970 park preservation staff began to take a more active role in managing the stabilization program at Chaco. Although WACC stabilization staff continued to work in Chaco during the 1970s, 1970 is considered the beginning of the park preservation program.