Nuclear power plants are often located in highly populated areas.
That’s because they were designed to provide electricity for people. And the closer the plants are to those people, the less energy required to get that power there.
So, just how close are these plants to people? And how many people are we talking about?
Those were the questions the journal Nature and Columbia University sought to answer when they created this Google Earth tool.
The researchers and writers found that two-thirds of the world’s 211 power plants each have more than 172,000 people living within a 19-mile radius. That’s more than the population around Fukushima.
Indeed, 21 plants have more than one million people living within 20 miles, and six have more than three million.
The KANUPP plant in Karachi, Pakistan, has the most people living in its immediate vicinity: 8.2 million within 19 miles. It's followed by Taiwan’s Kuosheng plant with 5.5 million people and another Taiwanese plant, Chin Shan, with 4.7 million.
The two operating plants in California include San Onofre, which has 610,000 people living within 19 miles, and 6.87 million within 47 miles.
Diablo Canyon, near San Luis Obispo, has a lower population density nearby: 160,000 within 19 miles and 470,000 within 47 miles.
But the researchers were quick to point out that population size can’t be used as the only factor when considering a plant’s safety.
Other issues include what the team called a “culture of safety,” including the “quality of maintenance and training, the competence of the operator and workforce and the rigor of regulatory oversight.”
In a recent inspection of the Diablo Canyon plant, the Nuclear Regulatory Commission found a host of concerns including the following summary from the New York Times:
- The plant had a single diesel-driven pump to provide emergency cooling water to a single reactor in case an earthquake cut off normal water flow. The pump could not have serviced both of the plant's reactors if they lost normal water supply simultaneously, commission staff said.
- Some doors at the plant required to protect against flooding of major safety equipment would not self-latch as required. One latch was "degraded," they said.
- The plant's six emergency diesel generators were located in the same plant area, and thus vulnerable to a "common mode" failure.
- An earthquake could cause a structural failure in the building where the fire truck is stored, and debris could block crews from using the truck.
- PG&E planned for a contractor to provide seawater for emergency cooling, but had no backup plan if an earthquake and tsunami blocked highways to the plant. PG&E intended to rely on the California National Guard to deliver diesel fuel for emergency generators if roads were impassable, but had no memorandum of understanding in place for the deliveries.
- Four 20-foot extension cables, used to operate fans that cool portable generators, were missing from their storage location.
A PG&E spokesman, Paul Flake, told California Watch in an interview earlier this month that all of these issues were being addressed.
At San Onofre, the concerns were fewer, but the NRC did note, “deficiencies in training and qualifications were identified for operators and support staff.”