Q&A/Japan's release of treated Fukushima wastewater

Taipei, Aug. 28 (CNA) Japan began its release of treated nuclear wastewater into the Pacific Ocean on Aug. 24, following a decision made during a Cabinet meeting two days earlier.

CNA has compiled the following Q&A to provide additional information on the discharge, including its possible impact and safety issues, as well as the response of neighboring countries.

What is treated nuclear wastewater?

The Fukushima Daiichi Nuclear Power Plant was hit by a tsunami in March 2011 as a result of the Tohoku Earthquake (known as the 311 Earthquake in Taiwan), which resulted in meltdowns of reactors in Units 1, 2 and 3 at the plant. As a result, water used to cool the reactors was contaminated with radioactive substances.

The Tokyo Electric Power Co. (TEPCO) used a purification device to remove most radioactive substances other than tritium, turning the contaminated water into Advanced Liquid Processing System (ALPS) treated water. The treated water has been stored at the power plant, but as the plant is nearing its capacity, the Japanese government has decided to discharge the 1.34 million cubic meters of treated wastewater into the ocean.

What is tritium? Is the treated nuclear wastewater released into the ocean hazardous?

Tritium is a hydrogen isotope that is used as an energy source in radioluminescent lights for watches. It is also used as a nuclear fusion fuel and for medical and scientific purposes.

According to experts, tritium only impacts human health when people are exposed to extremely large amounts.

In Japan, when tritiated water is discharged into the ocean by nuclear power plants, tritium content cannot exceed 60,000 becquerels (Bq) per liter. Meanwhile, World Health Organization (WHO) guidelines recommend a maximum tritium content for drinking water of 10,000 Bq per liter.

TEPCO has said it will dilute the Fukushima wastewater to have a tritium content of 1,500 Bq per liter before releasing it into the ocean.

How is the treated water discharged?

According to TEPCO, there are four steps. The treated water (stored in the power plant) will undergo after-treatment, after which it will be checked and measured to ensure that it meets Japan's standard for the discharging tritiated water into the ocean.

The third step is to further dilute the treated water with seawater.

Lastly, the diluted water will be stored in a well, and then discharged into the sea through underwater pipelines. TEPCO has also set up monitoring devices at the end of the pipelines to continue monitoring tritium concentrations in the ocean.

TEPCO plans to release a maximum of 500 cubic meters of treated water per day, and will keep tritium released into the sea controlled at 22 trillion Bq per year. It is estimated that it will take 30 years to discharge all the treated water.

How is safety ensured when discharging the wastewater?

According to TEPCO, discharge of the treated water will stop immediately if any abnormalities are detected by equipment during the process.

The valves in the pipelines will automatically stop the discharge if there is insufficient sea water for dilution, or if abnormal radiation is detected.

If an earthquake of magnitude 5 or stronger occurs, or if the Japanese government issues a tsunami or high wave warning, monitoring personnel at TEPCO will immediately stop discharge operations.

What impact will it have on people and the environment?

A TEPCO evaluation has shown that the released wastewater poses a low risk to humans and the environment -- a conclusion which has been backed by the United Nations' International Atomic Energy Agency (IAEA).

According to the IAEA, experts this week took samples from the first batch of diluted water discharged on Aug. 24, which confirmed that the tritium concentration was far below the operational limit of 1,500 Bq per liter.

Furthermore, the IAEA has said its staff will be on site for as long as the treated water is released, "in line with Director General Grossi's commitment for the IAEA to engage with Japan on the discharge of ALPS treated water before, during, and after the treated water discharges occur."

What is the response of nearby countries?

Taiwan has said it will keep a close watch on the situation and step up inspections by carrying out more tests on marine products caught in waters around Taiwan and imported from Japan.

Aug. 24: Taiwan steps up inspections as Japan releases nuclear wastewater

Aug. 22: Taiwan to keep close watch as Japan prepares to release nuclear wastewater

Taiwan's government has also launched an "Ocean Radioactive Information System" to provide forecasts regarding radioactive levels in the waters around Taiwan. According to the government's estimate, the nuclear wastewater will reach Taiwan within two years and by that time, levels of tritium concentration in the sea water will be very low, and pose no threat to the waters around Taiwan.

South Korea: The country said on Aug. 22 that it sees no problem with the scientific or technical aspects of Japan's plan to release the Fukushima nuclear wastewater, but it does not necessarily support the plan. Meanwhile, there were protests against the discharge of the treated water in Seoul on Wednesday.

China: China called the release of the treated wastewater a "selfish and irresponsible act," and announced that it would suspend imports of Japanese marine products from Aug. 24.

Hong Kong SAR also confirmed on Aug. 22 that it will ban marine products imported from some parts of Japan following the release of the treated water.

How have environmental protection groups responded?

Greenpeace opposes the Japanese government's discharge of treated nuclear wastewater into the Pacific Ocean. Hisayo Takada, project manager at Greenpeace Japan said: "We are deeply disappointed and outraged by the Japanese Government's announcement to release water containing radioactive substances into the ocean. Despite concerns raised by fishermen, citizens, Fukushima residents, and the international community, especially in the Pacific region and neighboring countries, this decision has been made."

Greenpeace Taiwan called for the Taiwanese government to negotiate with Japanese counterparts for compensation because of the impact it will have on Taiwan's fishing industry.

The group added that Taiwan should abolish nuclear power as an energy resource to prevent similar disasters to the Fukushima incident from happening in Taiwan.

At the same time, No Nukes Taiwan released a statement on Aug. 22 condemning the Japanese government's decision, and said it will participate in a demonstration in front of the United Nations headquarters in New York before the U.N. SDG Summit, slated to take place on Sept. 18-19.