Fukushima at the Forefront: 10 Years On

A 9.0 earthquake in the Pacific Ocean sent a massive tsunami to the coast of Japan. Upon landbreak, seawater came awash and forced regional emergency evacuations. Flooding, particularly in Fukushima prefecture, proved to have drastic additional consequences. Water over the walls of the Fukushima-Daiichi nuclear plant short circuited control systems and led to a triple reactor meltdown, releasing radioisotopes into the water that spilled into the surrounding region, deposited in the land and sea. A decade of deliberation and investigation over the events and their long lasting consequences remains underway, fueled by concerns about public health impacts and the action necessary to address preventable failures like TEPCO’s Fukushima plant in the future.

The casualties from the tsunami and difficulties evacuating resulted in nearly 16,000 deaths alone, but the coming ramifications would go beyond the flooding waters(1). Following the meltdown, unevacuated Japanese residents continued to live within a 20-30 km radius of the meltdown for up to a month. Later, this region was deemed too dangerous to stay in overnight. The Japanese government began zoning evacuations as many struggled to deal with the earthquake and tsunami, unaware “that the wind and the rain on March 15th brought radioactive particles” from the plant’s explosion(2). Tokyo Electric Power Company (TEPCO)’s failure to prevent a meltdown exacerbated an already tragic natural disaster, introducing additional health and environmental impacts atop the unprecedented housing displacement in the hundreds of thousands from flooding and nuclear evacuation zoning(3).

Measurements were taken throughout the region to inform government evacuation policy. Concerns were raised by residents, many who have by now moved back to their homes in dezoned regions. A study found that many points measured  “to be above 1 millisievert per year (mSv/yr)” where residents had already returned(4). The Japanese government’s zoning requires a background dose rate of 20 mSv/yr to be designated as a nuclear evacuation zone, the same as radiation workers’ occupational limits, while the international standard for the upper limit of radiation exposure to the public is 1 millisievert per year(5). The government has lifted evacuation orders on regions as radiation levels have decreased with time, though their attitude about transparency and disclosure has left many of the affected unwilling to possibly risk their health to return home as thousands remain in temporary shelters.

These samples’ activity is presented in Becquerels by weight or volume, and the labels on the bottom axis are location markers and each bar represents a different lab’s analysis of the sample. They were collected locally and sent to labs to be analyzed by various detectors and methodologies to provide a diverse array of data to be compared in the ILCs.  A 1 Becquerel (Bq) activity means there is 1 radioactive decay per second, a standard unit for measuring radioactivity. Measurements in Bq/kg or Bq/L allows determination of the activity in any amount of the irradiated material. The correlated Sieverts unit is used to measure the dose absorbed from a particular radiation exposure. The irradiated contaminants in soil and water made their way up the food chain through spread in air and sea, with measurable radioactive deposits across the Pacifc ocean.

Scientists have collaborated from across the globe providing risk assessment based on a decade of data collected from Fukushima, the Japanese countryside, to all the way across the Pacific ocean. High levels of radiation leave the immediate regions around the epicenter of the meltdown as mandated evacuation zones, though whether too early or not, people are gradually being allowed back home. Supplemented with government aid and a litany of consolation payments from TEPCO following extensive and ongoing civil suits, the extent of the harm may yet show face in latent health effects from elevated radiation exposure(9). Despite the lasting effects from Fukushima, a reactor, hit harder by the earthquake and a taller wave of the tsunami, shut down safely and is scheduled to restart operation in Onagawa, only 123 km (76 miles) away from the epicenter of the 2011 earthquake.

A separate company, Tohoku Electric, built and operated the plant in Onagawa with more stringent and thorough safety precautions, now cutting no corners at risk of the locals’ health as TEPCO had done for their Fukushima-Daiichi reactor. Tohoku Electric expects to pay “about 340 billion yen ($3.08 billion) in total on the anti-disaster measures” to safely provide essential green energy(10). The cost to TEPCO in response to the radioactive contamination and housing displacement may see no end in its increase.  Civil suits seeking compensation from TEPCO have payouts in hundreds of millions of yen for evacuees and those possibly risking their health in dezoned regions with elevated exposure. The preventable cost of the evacuations could have been prevented had it not been for TEPCO’s cost efficient safety measures, like a lower sea wall surrounding the already lower elevation reactor in a region historically impacted by tsunamis(11).