By Tom Doggett
WASHINGTON (Reuters) - U.S. citizens may be at risk from radioactive waste stored near nuclear plants as better training for federal safety inspectors and more on-site checks are needed, an internal government report showed on Friday.
The Nuclear Regulatory Commission's inspector general said in an audit that the NRC needs a formal, agency-wide training program to ensure its inspectors can do the best job when checking spent fuel storage sites.
Such sites are expected to be at all commercial U.S. nuclear power plants by 2025.
"When training requirements vary among staff, compromised oversight of (spent fuel storage) safety inspections can occur," said the report, released by the NRC.
"Specifically, there is an increased potential that inspections will overlook discrepancies, resulting in an increased risk to public health and safety."
Dry cask storage sites will play a growing role in holding the spent fuel at the country's 104 reactors now that the Obama administration has abandoned a permanent nuclear waste depository at Yucca Mountain, near Las Vegas.
The inspector general looked at the NRC's oversight of spent fuel storage installations, which generally consist of a concrete pad that holds used fuel inside steel cylinders surrounded by additional steel or concrete. These dry casks can be stored vertically or horizontally in concrete bunkers.
There are 47 such storage sites located at operating reactors and 10 located far from reactors.
The inspector general said the NRC does not require classroom training in concrete technology, the use of cranes for heavy loads and welding inspection techniques.
"However, specialized knowledge in these areas may be required when conducting critical inspection activities," the audit said.
The report said some NRC inspectors believe it is acceptable to walk around the perimeter of a dry cask storage pad.
Other inspectors insist on walking onto the pad to assess the condition of the casks and make sure the cooling vents on the containers are not blocked, it said.
"Birds or squirrels sometimes block these vents with nests," the report said.
The inspector general also said the NRC needed to define how far apart inspections should be. Inspections varied from one to almost six years, with many occurring every two years.
The NRC said it generally agreed with the inspector general's findings and recommendations.
(Editing by Dale Hudson)