Regulators say several minor problems found at an Ohio nuclear power plant in 2011 have been ongoing for about two years.
The Nuclear Regulatory Commission says the Perry Nuclear Power Plant near Cleveland must devise a plan to correct the problems.
In a March 5 letter, a regulator says plant owner First Energy Nuclear Operating Co. and federal inspectors found errors in following proper work procedures and documentation.
The letter also cites an incident in April 2011 when a poorly designed plan to pull a radiation monitor from the reactor's core left workers near a radioactive cable. The crew escaped exposure by leaving the area quickly.
A First Energy spokeswoman tells The Plain Dealer in Cleveland that the company has strengthened procedures and improved risk assessment and oversight.