The Union of Concerned Scientists has posted a great blog series "Role of Regulation in Nuclear Plant Safety." It's written by Dave Lochbaum, a degreed nuclear engineer who worked at American nuclear plants for 17 years. I think it's a better overview of NRC action and plant safety than any one incident. I've collected all the links here.

Series introduction: https://allthingsnuclear.org/dlochbaum/role-of-nuclear-regul...

Flooding at Nine Mile Point: Regulation and Nuclear Power Safety #1 https://allthingsnuclear.org/dlochbaum/flooding-at-nine-mile...

Three Mile Island Intruder: #2 https://allthingsnuclear.org/dlochbaum/three-mile-island-int...

Empty Pipe Dreams at Palo Verde: #3 https://allthingsnuclear.org/dlochbaum/empty-pipe-dreams-at-...

Yankee Rowe and Reactor Vessel Safety: #4 https://allthingsnuclear.org/dlochbaum/yankee-rowe-and-react...

Flooding at a Florida Nuclear Plant: #5 https://allthingsnuclear.org/dlochbaum/flooding-at-a-florida...

Containment Design Flaw at DC Cook Nuclear Plant: #6 https://allthingsnuclear.org/dlochbaum/containment-flaw-at-d...

Pipe Rupture at Surry Nuclear Plant Kills Four Workers: #7 https://allthingsnuclear.org/dlochbaum/pipe-rupture-at-surry

Anticipated Transient Without Scram: #8 https://allthingsnuclear.org/dlochbaum/anticipated-transient...

Naughty and Nice Nuclear Nappers: #9 https://allthingsnuclear.org/dlochbaum/naughty-and-nice-nucl...

Breaking Containment at Crystal River 3: #10 https://allthingsnuclear.org/dlochbaum/breaking-containment-...

Fatal Accident at Arkansas Nuclear One: #11 https://allthingsnuclear.org/dlochbaum/fatal-accident-at-ark...