Without fanfare, U.S. nuclear power regulators have overhauled community emergency planning for the first time in more than three decades, requiring fewer drills for major accidents and recommending that fewer people be evacuated right away.

The revamp, the first since the program began after the Three Mile Island accident in 1979, also eliminates a requirement that local responders always practice for a release of radiation.

The changes appear to clash with more recent lessons of last year's reactor crisis in Japan.

Under the new rules, the Nuclear Regulatory Commission and the Federal Emergency Management Agency, which run the program together, have added one new exercise: More than a decade after the Sept. 11, 2001, attacks, state and community police will now take part in exercises that prepare for a possible assault on their local plant.

'You need to be practising for a worst case, rather than a non-event.' —Jim Riccio, Greenpeace 

Still, some emergency officials say this doesn't go far enough.

And some view as downright bizarre the idea that communities will now periodically run emergency scenarios without practicing for any significant release of radiation.

These changes, while documented in obscure federal publications, went into effect in December with hardly any notice by the general public. They were at least four years in the works.

An Associated Press investigative series in June exposed weaknesses in the U.S. emergency planning program. The stories detailed how many nuclear reactors are now operating beyond their design life under rules that have been relaxed to account for deteriorating safety margins. The series also documented considerable population growth around nuclear power plants and limitations in the scope of exercises. For example, local authorities assemble at command centres where they test communications, but they do not deploy around the community, reroute traffic or evacuate anyone as in a real emergency.

The latest changes, especially relaxed exercise plans for 80-kilometre emergency zones, are being criticized by some local planners and activists who say the widespread contamination in Japan from last year's Fukushima nuclear accident screams out for stronger planning in the United States, not weaker rules.

Nuclear power industry praises changes

Emergency management officials say the revised standards introduce more variability into planning exercises and will help keep responders alert. The nuclear power industry has praised the changes on similar grounds.

On-site security forces at nuclear power plants have practiced defending against make-believe assaults since 1991 and increased the frequency of these drills after the 2001 attacks. The new exercises for community responders took years to consider and adopt with prolonged industry and government consultations that led to repeated drafts. The NRC made many changes requested by the industry in copious comments.

Federal personnel will now evaluate if state and local authorities have enough resources to handle a simultaneous security threat and radiation release. Their ability to communicate with on-site security officials during an attack also will be evaluated during exercises.

None of the revisions has been questioned more than the new requirement that some planning exercises incorporate a reassuring premise: that no harmful radiation is released. Federal regulators say that conducting a wider variety of accident scenarios makes the exercises less predictable.

However, many state and local emergency officials say such exercises make no sense in a program designed to protect the population from radiation released by a nuclear accident.

"We have the real business of protecting public health to do if we're not needed at an exercise," Texas radiation-monitoring specialist Robert Free wrote bluntly to federal regulators when they broached the idea. "Not to mention the waste of public monies."

Anti-nuclear activists unimpressed

Environmental and anti-nuclear activists also scoffed. "You need to be practising for a worst case, rather than a non-event," said nuclear policy analyst Jim Riccio of the group Greenpeace.

A FEMA representative declined multiple requests for an interview and instead released a statement. The agency acknowledged that a simulated problem during a no-release exercise is handled on plant grounds. Federal planners say this exercise still requires community decision makers to mobilize and set up communication lines with officials on the site, practicing critical capabilities, even though they won't need to measure and respond to radiation.

While officials stress the importance of limiting radioactive releases, the revisions also favour limiting initial evacuations, even in a severe accident. Under the previous standard, people within two miles would be immediately evacuated, along with everyone eight kilometres downwind. Now, in a large quick release of radioactivity, emergency personnel would concentrate first on evacuating people only within 3.2 kilometres. Others would be told to stay put and wait for a possible evacuation order later.

Timothy Greten, who administers the community readiness program at FEMA, said it wouldn't be necessary to tell people to stay put "if you could evacuate everybody within 10 or 15 minutes."

But he said hunkering down can be safer in some locations and circumstances, "especially for a short-term solution."