NEPA requires that, before certain decisions can be made, all reasonable alternatives must be examined. If this approach is taken, then the public can get involved in describing and discussing all reasonable alternatives. In such a process, all viewpoints can be aired. Cultural values, historical perspectives, and local concerns can all be brought into the decision, along with issues of technology, costs, and benefits. People can look at all the alternatives and can decide which one they prefer.
Risk assessment suppresses such discussions.
However, when people are merely doing a risk assessment, this principle cannot come into play. That is simply not a question that risk assessment asks. This decision has then been justified by a risk assessment. This is a typical use of risk assessment, to justify a decision that was made by lawyers, financial analysts, bankers, corporate officials, and elected officials. Here the public will have a great deal to say, and the search for an answer can be a model of democracy.