Japan’s weather agency alerted thousands of citizens in Kagoshima that the Sakurajima volcano was teetering on the brink of eruption. The alarm comes just a few weeks after the Kyushu Electric Power Co. restarted the No. 1 reactor at the Sendai Nuclear Power Plant, which is a mere 30 miles away from the volcano.^{(1, 2)}

Officials have been keeping an eye on the Sakurajima volcano. Their have been an estimated 700 small volcanic earthquakes at the site this year. On Saturday, however, their were an estimated 1,023 volcanic earthquakes. The spike in volcanic activity at Mount Sakurajima in Kagoshima Prefecture forced the Japan Meteorological Agency to issue a level four warning on a five point scale.  The number of quakes dropped to 71 the following Sunday. Nevertheless, Japanese residents aren’t out of the woods; although, evacuation notices did cause people to flee the woods.

Threat level raised

Before the alert level was raised, the alert was set at level three, which prohibits people from entering the mountain area. A spike in tectonic movement indicated that the mountain had swelled, which caused the alert level to be raised to four.⁽³⁾

Level four is the highest for Mount Sakurajima since the current volcanic warning system was put into effect in 2007. After the alert level was raised, the Kagoshima Municipal Government issued an evacuation advisory for those near the volcano, including 77 residents. All of the residents had evacuated the area by Saturday evening. Officials report that the evacuation may last a week or longer.⁽³⁾

The volcano resides off the coast of Kagoshima, which is home to approximately 600,000 people. The agency warned that the evacuation of the city may be necessary. According to the Japanese Meteorological Agency, “The possibility for a large-scale eruption has become extremely high for Sakurajima.”⁽⁴⁾

Public protest at the Sendai plant

Restarting the Sendai Nuclear Power Plant provoked public protest just a few weeks ago. Approximately 150 to 200 protesters gathered outside the nuclear power plant on August 11th. Protesters created a barricade with their cars at the front gate entrance in order to prevent officials from restarting the reactor.⁽⁵⁾

Sendai was the first nuclear reactor to be reactivate since the Fukushima disaster in 2011. Power plants are now required to pass safety regulations in order to reopen. Nevertheless, critics noted that the power plant did not meet safety standards, since it had not adequately developed an evacuation plan in face of a volcanic eruption.⁽²⁾

Despite these concerns, officials reactivated the plant on August 11. Japan has relied heavily on imports since power plants throughout the country closed after the Fukushima disaster, and energy prices have also increased. In order the become more energy self-reliant, the Japanese government has been pushing to reactivate power plants.

Japan’s nuclear reactors are still susceptible to natural disasters. The Meteorological Agency warned that another volcano near the plant, Ioyama, was at risk of erupting. Sendai also is near five giant calderas , which resemble craters that are formed by the inward collapse of volcanoes.

Ring of Fire

The country of Japan lies along the Pacific Ring of Fire, which is host to an abundance of tectonic activity. Approximately 90 percent of the world’s earthquakes occur in the Ring of Fire, which also happens to be home to 75 percent of the world’s volcanoes. Their are an estimated 100 active volcanoes in Japan.⁽⁵⁾

Sakurajima last erupted in 2013, killing 63 people. Swelling of the volcano has subsided since Saturday, but officials remain on high alert. “We need to remain on alert because it is not known when magma will start to rise again and when a major eruption will occur as a result,” warned the Meteorological Agency.

Reactivating the power plant sparked public protests. Ironically, officials are now worried that the volcano may spark the nuclear reactor.⁽⁴⁾

Sources include:

(1) WSJ.com

(2) FukushimaWatch.com

(3) Japantimes.co.jp

(4) Independent.co.uk

(5) Mainichi.jp

(6) UniverseToday.com