The Coralville Dam has been holding back the Iowa River since 1958. The Iowa River crested in 2008 at 31.5 feet, almost ten feet above flood stage in Iowa City. Terracon's field staff worked for the University of Iowa to collect air and surface samples to assess whether the cleanup contractors had mitigated the bacterial and fungal hazards left behind by the floodwaters. Utilizing a team of more than 60 staff from 15 different offices across the country, Terracon was able to cover multiple building sites simultaneously. Phase two involved observing the cleanup contractors as they cleaned and restored the heating, ventilating, and air-conditioning (HVAC) systems in the remaining flood-affected buildings. For phase three, the university brought in over 20 mobile trailers to use as temporary classrooms and offices for the spring semester of 2009. Prior to occupying the trailers, Terracon conducted formaldehyde testing of the ambient air in some of the new trailers to address concerns of formaldehyde out-gassing from the building materials.