[6] Cities within 50 miles: In 1987, PECO was ordered by the Nuclear Regulatory Commission (NRC) to indefinitely shutdown Peach Bottom-2 and -3 on March 31 due to operator misconduct, corporate malfeasance, and blatant disregard for the health and safety of the area.

Among the incidents cited by the NRC: security guards were overworked, one guard was found asleep on the job, 36,000 gallons of "mildly radioactive water" leaked into the Susquehanna River, PECO mislaid data on radioactive waste classification causing misclassification of a waste shipment, and a major fire occurred in the maintenance cage of the Unit 3 turbine building on March 4, 1987[citation needed].

In September 1988, NRC Chairman Lando Zech told senior management officials of PECO, "Your operators certainly made mistakes, no question about that.

[citation needed] Robert P. Crosby became the primary Organization Development influence during the PECO Nuclear turnaround following the Peach Bottom shut down.

He used The Interpersonal Gap model by John L. Wallen along with a unique T-group method known as Conflict Management (and later as Tough Stuff in other business applications) to speed culture change, and applied his own version of Daryl Conner's Sponsor Agent Target model to improving and shortening outage management.

[7][8] By 1996, both Limerick and Peach Bottom were designated excellent by INPO, and given strong Systematic Assessment of Licensee Performance (SALP) ratings by the NRC.

[9] The Nuclear Regulatory Commission's estimate of the risk each year of an earthquake intense enough to cause core damage to the reactor at Peach Bottom was 1 in 41,667; according to an NRC study published in August 2010.