Discuss the three major eras of environmental law in the United States. What key

The first major era addressed public land management, whereby western expansion was encouraged. It promoted settlement of the West and utilization of its resources. The end of this era saw the development of the national park system, aimed at preserving pieces of land for public use. The second major era sought to address the impacts of the first major era of environmental law and lasted through the beginning of the 20th century. Laws included declaring some areas off? limits to logging and hunting, creating wildlife refuges, and protecting forests. The third era was in response to the increasing effects of environmental pollution. Pollution policy was driven by new evidence, such as Carson's Silent Spring and the burning of the Cuyahoga River, which focused attention on the nearly nonexistent environmental standards in this country. Laws were passed regulating air and water quality and the types of pesticides that could be used. 

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