"At the request of the U.S . Department of Energy - Laramie Energy Technology Center (LETC) , the EPA 's Environmental Monitoring System Laboratory - Las Vegas performed a remote sensing study of two experimental energy conversion projects near Rock springs and Hanna, Wyoming . Color infrared aerial photography , digital multispectral scanner data, and ground level photographs were acquired and analyzed to monitor the extent of surface disturbance associated with past and present site operations. Analysis results of both photographic and digital multispectral data indicated the presence of substantial surface disturbance at both projects. This disturbance consisted primarily of removal of natural vegetation , exposure of bare soils , installation of well casings, and erection of support facilities. At both sites, photographic analysis indicated some areas of surface disturbance exhibiting reclamation and/or natural vegetative recovery. At the Rock Springs experimental sites, evidence of surface disturbance was noted in association with six in situ oil shale retorting areas . At the Hanna experimental site , surface disturbance was noted in association with four underground coal gasification areas. As the Rock Springs site , surface disturbance consisted mainly of the partial disruption or removal of the natural vegetation mosaic, exposure of bare soils, and the erection of small support buildings within the permit area."