In 2006, unexpected discoveries of buried World Trade Center (WTC) debris and human remains were made at the World Trade Center mass disaster site. New York City's Office of Chief Medical Examiner (OCME) was given the task of systematically searching the site for any remaining victims' remains. The subsequent OCME assessment and archaeological excavation conducted from 2006 until 2013, resulted in the recovery of over 1,900 victims' remains. In addition, this operation demonstrated the essential skills archaeologists can provide in a mass disaster recovery operation. The OCME excavation data illustrates some of the challenges encountered during the original recovery effort of 2001/2002. It suggests that when understood within the larger site recovery context, certain fundamental components of the original recovery effort, such as operational priorities and activities in effect during the original recovery, directly or indirectly resulted in unsearched deposits that contained human remains.