It has a lot to do with outside groups using the bureaucratic process to slow things down. A popular method is using what it's called environmental impact study

It has a lot to do with outside groups using the bureaucratic process to slow things down. A popular method is using what it's called environmental impact study. If an EIS identifies that some little field mouse might be harmed if the nuclear power plant is built, an outside organization can use that report to sue to stop the entire project. This tactic has been used countless times to stop everything from copper mining, to solar farms. Worse, still, if a group sues, and they win, the government picks up the tab. It's called environmental justice lawsuits, and they have utterly destroyed most Green projects in America.