The Congress could make the Nuclear Power plants immune from lawsuits................
Yep.
They could pass a law that all new reactors are built on federal land and that any facilities built on that land are exempt from state and local regulations and lawsuits, and any lawsuits brought by private entities, except taxation. This also includes any water withdrawals that may be necessary for construction and operation of facility.
Here’s how that could work: Company A purchases a piece of land and as part of the purchase, then donates that land to the feds. All of this must be done prior to any announcement of intent to build a reactor.

The Congress could make the Nuclear Power plants immune from lawsuits................
><
Yes, and blanket pardons for the developers of small nukes!