No nuclear plants have been affected by the eruption, Kyushu Electric Power Co stated, including the Sendai nuclear plant, which was restarted in August and is located about 160 kilometers (100 miles) south of Mount Aso… Japan is located in a region known as the “Ring of Fire,” which consists of a horseshoe-shaped band of fault lines and volcanoes running around the edges of the Pacific Ocean. There are over 100 active volcanoes in the area.