Burlington ? Increased security at the Wolf Creek nuclear power plant since last year’s Sept. 11 terrorist attacks on the United States has cost about $2 million.

The steps taken included hiring more armed guards and installing concrete barriers around the plant, as well as other less visible changes that are classified.

The Wolf Creek Nuclear Operating Corp. will continue to spend about $1 million a year on increased security measures, Otto Maynard, head of the company, said Thursday during a media tour of the plant.

Maynard said that next week the nuclear power industry would release a report saying that the nation’s 103 power plants could withstand a direct hit from a Boeing jet, similar to those that crashed into the World Trade Center and the Pentagon last year.

The industry-paid engineering analysis was conducted in response to public anxiety and statements by the Nuclear Regulatory Commission that some critical parts of the plants may be vulnerable to an airplane attack.

The plants were designed to withstand tornadoes and earthquakes but not fully loaded jets. When Wolf Creek was being designed in the 1970s, the worst scenario made public was a burst pipe.

A plane crashing into the Wolf Creek containment building, where the nuclear reactor is housed, would damage the plant and cause it to shut down for a long time, Maynard said. That could potentially disrupt the state’s power supply.

But no radiation would be released, and the nuclear fuel rods would not be damaged, Maynard said.

The building that houses spent nuclear fuel, he said, also could withstand the impact of a jet.

Information provided during Thursday’s tour was intentionally vague for security reasons, the company said.