Holes and cracks in nuclear reactors in Ohio and South Carolina have caught government regulators and nuclear industry leaders by surprise. Inspection programs are being questioned as concerns rise over the aging nuclear facilities.

The hole found in a reactor at the Davis-Besse Nuclear Plant in Ohio was thought to have been impossible. A press release issued by the Nuclear Information and Resource Service had this to say: "Operators discovered a cavity had eaten through 6-inches of carbon steel on the top of the 61/2 -inch thick reactor pressure vessel, the apparent result of corrosive coolant leakage form the reactor core. Less than a half inch of the reactor vessel's stainless steel liner remained in the bottom of the 4"X5"X6" cavity separating the reactor;s highly radioactive and pressurized internal environment (2500psi) from blasting into the reactor containment building damaging safety equipment and possibly setting into motion a core melt accident. Initial company inspections additionally found cracks in the welds on five of the 69 nickel alloy sleeves that penetrate pressure vessel head to allow for control rod insertion to safely shutdown the reactor."

The cracks found early last year at the Oconee Unit 3 reactor plant in South Carolina were found to be less urgent. But nuclear experts said that if the cracks had expanded they could have caused the nozzle to separate, causing a loss of cooling water inside the reactor.

Both problems were found before they posed an immediate safety threat. Nuclear Regulatory Commission officials are viewing the Davis-Besse and Oconee discoveries as the most important safety issue facing the nuclear industry since the Three Mile Island accident 23 years ago.