Public disclosure of plans that affect all of us can lead to better decision making and ultimately save tax dollars. A major event that led Henry "Scoop" Jackson, a Senator from Washington State, to write new national legislation was the Santa Barbara, California oil spill in 1969. The federal government provides oil drilling permits so more transparency, coordination, and public involvement was needed on all federally-permitted or funded projects.
President Richard Nixon, a Republican, signed the National Environmental Policy Act (NEPA) in 1970. The law established the Council on Environmental Quality (CEQ) located in the Executive Branch to set policy for federal agencies. The first test of the law came by citizens living near the Calvert Cliffs nuclear power plant in Maryland who sued the Atomic Energy Commission (AEC). AEC required utilities to prepare environmental reports but did not plan to consider the document unless issues were raised to the licensing board. The Supreme Court in 1971 sided with the citizens requiring federal agencies to consider NEPA to the "fullest extent possible." The new NEPA law allowed citizens to tell the federal government that environmental impacts or protection of cultural resources must be evaluated before projects are approved.
The way the process typically works is that each agency follows CEQ policy and develops their own regulations to comply with NEPA. The agency must conduct an environmental assessment (EA) -- if the proposed action is considered a "major federal action" then an Environmental Impact Statement (EIS) must be prepared that allows for public participation with obtaining scoping and draft EIS comments. The EA may determine a Finding of No Significant Impact (FONSI) is warranted.
In 2007, I dedicated some time between paid consulting projects to research and publish an article on the NEPA process by examining methods to extract uranium needed for nuclear power. The Nuclear Regulatory Commission released a Generic EIS for in-situ uranium mining -- the industry advocated that site-specific EIS reports would not be needed because the technical processes would be similar at each site. However, to keep citizens informed in the areas of the mining, I advocated and NRC agreed that site-specific EIS reports would be needed. Here is a link to the article.