Booming with subdivisions and office parks, the region surrounding the Shearon Harris nuclear plant has doubled in population over the past decade, making the Triangle one of the fastest-growing nuclear evacuation zones in the nation.
Nevertheless, officials have said they could evacuate the entire zone, which extends 10 miles in all directions from the nuclear plant, in an afternoon. That's primarily because new roads have been built to accommodate the growth.
But two developments could change the dynamics of evacuation planning. Current estimates - clearing out the entire Shearon Harris zone in 4 hours and 10 minutes - do not account for a significant chunk of the zone's population growth.
And in the wake of the nuclear disaster that followed Japan's earthquake and tsunami this year, some question whether a 10-mile evacuation zone is large enough.
Ten miles has been the standard for U.S. nuclear plant evacuation plans since 1980, the year after the Three Mile Island nuclear accident in Pennsylvania exposed the lack of emergency planning at the nation's nuclear plants.
Few had reason to question the standard until this spring, when U.S. officials warned Americans to move at least 50 miles from Japan's Fukushima reactors, which were spewing radiation after a tsunami disabled the plants.
"It blew me away," said Joshua Creighton, director of Wake County's Division of Emergency Management. "I had my TV on in the office, and it made my head whip around. I said 'What? Who? Where? Say that again.'
"I'd never heard of any number other than 10 (miles)," he said.
Downtown Raleigh, where Creighton works, sits outside the nuclear evacuation zone, but less than 25 miles northeast of the Shearon Harris nuclear plant, operated by Progress Energy, and it had always been assumed that Raleigh's 400,000-plus residents would not need to be evacuated if a nuclear accident happened here.
The same goes for Durham, Cary and other sprawling communities, some of which were farms and pastures when the Shearon Harris plant went into service in 1987 in southwest Wake County.
Last month, the Union of Concerned Scientists, a nuclear watchdog organization, urged the NRC to scrap one-size-fits-all evacuation zones and instead correlate the size of each zone to local populations and road capacity, noting that a lethal radioactive release could travel more than 100 miles downwind.
"It's a false sense of security," said David Lochbaum, director of the organization's nuclear safety project. "With population centers just outside the 10 miles, it becomes difficult to wave a magic wand and get those people out of the way unless you've planned ahead."
The Nuclear Regulatory Commission is sticking to its 10-mile rule for now, saying the Japanese evacuation order does not set a new safety precedent for U.S. nuclear evacuation zones.
"That was based on a worst-case scenario, and there was a lack of information," said NRC spokesman Roger Hannah. "You're talking about six reactors in one location, whereas in this country most sites are one or two reactors."
Rarely limiting growth
When the 10-mile rule was established, many nuclear plants were built in sparsely populated areas, and Shearon Harris was still under construction. About 29,000 people lived within 10 miles of the Harris plant in 1987, when its lone reactor began generating electricity. Today, more than 122,000 live and work in the emergency planning zone.
The circular evacuation zone that includes parts of Wake, Chatham, Lee and Harnett counties today is home to 77 institutions such as schools, nursing homes, day care centers, hospitals and other facilities.
There are no federal restrictions on development or the number of people living within the emergency zones. The Indian Point nuclear plant near New York City has 310,000 people living in its evacuation zone, and at least a dozen nuclear plants have bigger populations within 10 miles than Shearon Harris.
According to Progress estimates, the Shearon Harris evacuation zone population will surpass 220,000 by the year 2040.
Until recently, Wake officials had not tried to limit development in the 10-mile area. But even before the Japanese nuclear disaster, Wake County and other local officials had agreed to limit development within five miles of Shearon Harris out of concern that emergency planners could be overwhelmed if an evacuation became necessary.
It is one of the rare cases where land-use planning has taken a nuclear plant into consideration, although the area affected in unincorporated Wake County is just 3.9 square miles.
Currently, fewer than 4,000 people live within five miles of the plant, on land that is not owned by Progress Energy.
But a study done by Wake County in 2009 projects that the area could grow to 104,000 residents and workers by 2025 if high-density development were permitted.
If that happened, it would take 6.7 hours to evacuate the area - and that's just to the five-mile line from the nuclear plant.
Wake County's 2009 "Harris Lake Drainage Basin Land Use Study," prepared for the county and for Apex, Holly Springs and Fuquay-Varina, adopts a regional planning guideline of low-density development, no more than four homes per acre.
That would limit development to 52,000 residents and workers within the five-mile zone by 2025.
Even with low-density development, planners would need up to 5.4 hours to get everyone evacuated to the five-mile line, where the evacuees would then join the broader evacuation flowing out to the 10-mile mark.
An evacuation of the entire nuclear zone would easily qualify as one of the largest population movements the state has ever overseen. State officials don't keep records of evacuation sizes, but they say that more than 100,000 have fled the Outer Banks in advance of hurricanes.
Wake County Manager David Cooke said the nuclear plant should not be ignored in land planning, but the population in the Shearon Harris evacuation zone does not raise concerns that emergency planners can't handle.
"Many communities have nuclear power plants," Cooke said. "Those communities have not decided, 'Let's not ever grow again.' That's not realistic."
A dated estimate
Within the emergency planning industry, North Carolina's planners are considered to be among the best in the nation, largely because of the state's experience with preparing for hurricanes.
But no amount of planning can anticipate every scenario, particularly events that draw large crowds to the Triangle, said Bill Gentry, director of UNC-Chapel Hill's Community Preparedness and Disaster Management Certificate Program.
"It's going to be a huge chore," Gentry said of nuclear evacuation estimates. "They are fairly on target for five-days-a-week during normal hours. Where it's going to stretch their planning and their numbers is if it's after midnight on a weekend, or if State and Duke are playing a home football game."
Progress Energy's evacuation consultants, KLD Engineering, say the entire population within 10 miles of Shearon Harris could be cleared out within 4 hours and 10 minutes - whether it's sunny, raining or snowing. However, that estimate is based on a dated population estimate of about 74,000; it will be recalculated next year.
Still, it's among the speediest nuclear evacuation estimates in the nation. And it's a key reason for the absence of urgency here about whether rapid development near a nuclear plant could risk public safety.
"It seems not to bother anybody to go out there and do a development or to move there," said Mike Sorensen, the planning director for Fuquay-Varina, less than 10 miles from the plant. "They're going on faith that the evacuation plan is safe."
The evacuation estimate, however, assumes the roads are passable. If roads are iced over, covered with snow as a nuclear accident is brewing, residents would be instructed to "shelter in place" - that is, remain at home and shut off heating systems, close windows and place damp rags under door thresholds - until road conditions improve. Emergency planners acknowledge that some would ignore instructions and try to get away.
Neither federal nor state officials require that a nuclear zone be evacuated within a certain time.
New roads help
Evacuation times don't necessarily increase as populations grow. Of all Progress Energy nuclear plants, Shearon Harris has the biggest evacuation zone population, but the shortest estimated evacuation time.
The evacuation time has been improving in recent years. In 2007, the evacuation estimate for Shearon Harris, assuming a population of 74,000, was 5 hours and 46 minutes.
The expansion of Interstate 540 and the widening of I-40 and U.S. Highways 1 and 64 have allowed planners to shave more than 90 minutes from the 2007 estimate, according to the most recent study by KLD Associates.
The KLD study assumes that in the event of a nuclear accident, thousands of people will flee who live outside designated evacuation areas.
The Shearon Harris evacuation timing estimate assumes that 50,000 people living beyond the 10-mile zone would spontaneously flee if an evacuation were ordered, said Reuben Goldblatt, a project manager at KLD, based in Hauppauge, N.Y.
This caravan, estimated at 25,000 vehicles, is factored into KLD's evacuation time estimates for Shearon Harris.
Evacuation times could be affected by a number of complicating factors - such as a terrorist attack or natural disaster or some other unforeseen event - making the estimates far from assured.
"They present an uncertain scenario, since they're rarely validated using empirical data on people's behavior," said John Sorensen, an evacuation researcher with the Oak Ridge National Laboratory's Hazards Management Group. "We don't have a good idea if the engineering estimates are within the ballpark, or way low, or way high."
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