Japan’s government is conducting an investigation over the distribution of concrete made from crushed stones, sold to more than 200 companies, and used in new condo construction which may contain radioactivity from the Fukushima nuclear disaster.
A new condo building located in Nihonmatsu, Fukishima Prefecture, containing the concrete in question, was detected with readings of radioactive cesium up to 1.2 microsieverts per hour recorded inside the building, higher than readings on the outside, according to Japan’s NHK.
Gravel used for making the concrete originated from a quarry near Namie, which had been designated an evacuation zone following the earthquake and tsunami last March.
More than 5,000 tons of crushed stone was shipped to 19 companies from the quarry in the weeks following the nuclear disaster, the plant’s operator stated. The quarry company president told reporters on Monday he did not imagine his quarry gravel could cause such a problem. “I never imagined the crushed stones were radioactive when I shipped them. I feel very sorry for those who have been involved,” the Japan Times reports.
Japan’s Ministry of Economy, Trade and Industry did not impose radiation restrictions on crushed stone used for making concrete, nor did it curb shipments of the gravel.
Namie began its checks for radiation after a junior high school girl living in the new condo building showed an exposure reading of 1.62 millisieverts during a three-month period beginning in September, a local authority said.
Japan’s Chief Cabinet Secretary, Osamu Fujimura, said the government will study the gravel’s distribution routes from the quarry. According to the Japan Times, he said annual radiation exposure levels in the new building will not attain a 20 millisievert level, the mandatory evacuation level.
The contaminated concrete news coincides with demonstrations over the weekend in Yokohama, Japan. Thousands of protesters against nuclear energy were on the streets there on Saturday, marking the start of a two-day conference dedicated to increasing a growing tide against atomic power.
The conference, Participants of the Global Conference for a Nuclear Free World, called for “full transparency” by Japan’s government and Tokyo Electric Power Company, the Fukushima plant operator, according to the Mainichi Daily News.
The conference’s Yokohama Declaration recommended the government conduct a comprehensive collection of data regarding the country’s radioactive contamination of people, food, air, water and soil in order to minimize radiation exposure to humans after the Daiichi nuclear meltdown.