RICHLAND  (AP) — U.S. Energy Secretary Rick Perry says his agency will conduct a study to determine what led to the collapse of a tunnel at Hanford Nuclear Reservation in Washington state.

Perry said Wednesday that the tunnel obviously deteriorated and the question that needs to be answered now is why that was allowed to happen.

Perry made the comments during a tour of Los Alamos National Laboratory in northern New Mexico, another one of the federal sites dealing with the cleanup of Cold War-era waste from decades of bomb-making and nuclear research. Los Alamos was among the federal installations that helped develop the first atomic bomb during World War II.

Perry acknowledged the problem with nuclear waste, saying the nation can no longer kick the can down the road since American lives and the health of some citizens are in jeopardy.

He said the federal government has failed over the years to remove the waste in a timely manner.

He pledged to make progress on a multi-billion dollar problem that has transcended previous administrations.