Environmental discrimination has historically been evident in the process of selecting and building environmentally hazardous sites, including waste disposal, manufacturing, and energy production facilities. The location of transportation infrastructures, including highways, ports, and airports, has also been viewed as a source of environmental injustice. Among the earliest documentation of environmental racism was a study of the distribution of toxic waste sites across the United States.[8] Due to the results of that study, waste dumps and waste incinerators have been the target of environmental justice lawsuits and protests.[9]