11/03/2026
What do you do with millions of tons of radioactive water?
On March 11, 2011, a massive 9.0 earthquake and a subsequent tsunami struck the east coast of Japan’s Tōhoku region, resulting in one of the most devastating catastrophes in recent history. With an estimated 23,000 casualties, and 400,000 infrastructures damaged amounting to approximately $195 billion to as much as $305 billion - no wonder the disaster is remembered as the “Great East Japan Earthquake Disaster.”
Among the damaged infrastructures is the Fukushima Daiichi Nuclear Power Plant which is built at the coast of the Ōkuma, Fukushima. The plant's emergency generators and cooling systems were damaged by the tsunami, leading to overheating and the meltdown of three of the plant’s nuclear reactor cores - this became known as the “Fukushima Daiichi Nuclear Disaster.” As a result, water had to be continuously pumped in to cool the debris and prevent further radioactive decay, keeping the damaged reactors stable, creating thousands of tons of radioactive water. To safely manage this radioactive wastewater, the Advanced Liquid Processing System (ALPS) was developed.
Let’s explore and dive deeper—not into the radioactive water—in this week’s Wisdom Wednesday!
ALPS works like a giant chemical sponge and sieve, designed to remove 62 types of radioactive materials from the contaminated water. Before entering ALPS, radioactive wastewater undergoes pre-treatment to remove oil and suspended solids through mechanical filtration, and highly concentrated isotopes such as cesium-137 and strontium-90 by performing chemical precipitation and using adsorbent minerals such as zeolites and titanium-based adsorbents. This pre-treatment acts as an initial filtration, removing most concentrated contaminants so the ALPS can efficiently capture the remaining trace of radionuclides.
Once pre-treated, the water flows through 16 adsorption towers comprising 14 primary towers and 2 polishing towers. Inside each tower are adsorbent materials such as iron oxides, titanates, activated carbon, and ion-exchange compounds, capturing radioactive ions by selectively binding contaminants like strontium, iodine, and antimony. Each of the 14 primary towers target different radionuclides, allowing the ALPS to progressively remove contaminants as the water passes through the stages. The final two towers act as polishing filters for final adsorption, capturing any remaining trace isotopes.
Despite all these, the ALPS cannot remove tritium (³H), a radioactive isotope of hydrogen with two neutrons instead of none. Tritium forms tritiated water (HTO or T₂O) by replacing the normal hydrogen atom (¹H) attached to water (H₂O, which is chemically identical to normal water). Because of this, the conventional filtration and adsorption processes made by the ALPS cannot separate it efficiently. Tritium emits beta radiation (ß), which cannot pe*****te human skin, but becomes a larger risk when ingested often in the form of tritiated water since it can easily spread to different parts of the body.
Since August 2023, Japan has begun gradually releasing ALPS-treated water diluted with seawater into the Pacific Ocean to lower the concentration of tritium being released. This project is expected to continue for about 30 years with the ultimate goal of being part of decommissioning the Fukushima Daiichi site. While debated internationally, monitoring organizations state the treated water meets safety standards.
When asked, “What do you do with millions of tons of radioactive water?” The answer lies in systems like ALPS, where engineered materials help with the site recovery, removing radioactive contaminants, and making long-term cleanup possible.
Content by: Lyn Mary A. Blancaflor
Design by: Soleil Jumaquio and Yzhae Villaruel
Are you ready to be WEISS-er? Access our references to learn more at tinyurl.com/upmssWW
Wisdom Wednesday is brought to you by the UP Materials Science Society. Want more knowledge? Stay tuned next week for another amazing Wisdom Wednesday!
