Milestone of the Environmental Movement

During the post-World War II era, a growing awareness of environmental issues began to shape American society and politics. The environmental movement gained momentum in the 1960s and 1970s, responding to concerns about pollution, conservation, and the effects of industrialization. Key events and publications, such as the release of Rachel Carson's Silent Spring in 1962, significantly raised public consciousness about environmental degradation. In this context, which of the following events is most closely associated with a significant milestone in the modern environmental movement during the late 1960s?