Tokyo Electric Power Co. has started diverting uncontaminated groundwater at the crippled Fukushima No. 1 nuclear power plant into the sea, in an attempt to reduce the vast quantity of radioactive water accumulating on site.
Tokyo Electric Power Co. has started diverting uncontaminated groundwater at the crippled Fukushima No. 1 nuclear power plant into the sea, in an attempt to reduce the vast quantity of radioactive water accumulating on site.
At a news conference on May 21, Chief Cabinet Secretary Yoshihide Suga said the start of the water bypass project represents a “small step” in tackling the buildup of contaminated water, which has been a major source of public concern.
At 10:25 a.m. on May 21, the utility started releasing about 560 tons of water that it had pumped from 12 wells located in the plant compound in April. It took about two hours to release the water.
Each day 400 tons of groundwater have been seeping into contaminated reactor and turbine buildings at the Fukushima No. 1 plant. TEPCO estimates that the groundwater bypass project will reduce the amount by 20 to 100 tons per day.
TEPCO released water from storage tanks into the sea at locations south of the No. 1 to No. 4 reactor buildings through drainpipes it installed in spring 2013.
The Fukushima Prefectural Federation of Fisheries Cooperative Associations gave its consent to the water bypass project in March.
“It was an agonizing decision for fishermen in the area to endorse the plan,” Suga said. “We will have the industry ministry strictly instruct TEPCO to abide by its rules on contamination levels of water to be released.”
The 12 wells intercepting the underground flow of water were dug into the mountainside of the reactor buildings. Contamination levels of the water pumped from the wells are checked while it is stored in surface tanks.
TEPCO said it confirmed that the concentration of radioactive materials in the water released on May 21 was below its standard on water allowed to be released into the sea.
Local municipalities have endorsed the bypass project on condition that contamination levels of intercepted water remain below the standard and the water is closely monitored by TEPCO.
The utility and Fukushima Prefecture will conduct sample checks of seawater off the plant to investigate the impact of the water bypass project.
After the nuclear crisis unfolded, TEPCO drew criticism from local fishermen and others when it released water with relatively low contamination levels into the sea to make space in storage tanks for highly contaminated water.
Local residents have come to feel mistrust toward the utility after the plant experienced a series of accidental contaminated water leaks.