2024 "Huashu Cup" International Mathematical Contest in Modeling
MCM
Problem A:
Radioactive Wastewater from Japan
Photo Credit: VCG
Background
The March 2011 earthquake off Japan's east coast triggered the Fukushima Daiichi
accident, which resulted in meltdowns at three nuclear reactors and melted debris
from nuclear fuel after a massive tsunami knocked out cooling systems at the plant.
To cool the melted nuclear fuel, seawater is continuously injected into the reactor,
resulting in a large amount of radionuclide-contaminated cooling water. Despite the
opposition of the people of all countries, the Japanese government began to forcibly
discharge the treated Fukushima radioactive wastewater into the Pacific Ocean on
August 24, 2023. The total amount of radioactive wastewater contaminated with
radionuclides is more than 1 million tons. The whole project is expected to last at least
30 years. The appendix is the four-wheel discharge plan announced by the Japanese
government.
These nuclear effluents contain Tritium, a radioactive isotope that can remain in the
environment for a considerable amount of time. The degree of contamination of
radioactive elements refers to the amount of radioactive elements present in the
environment and the degree of potential harm to humans and ecosystems. It is usually
assessed by measuring parameters such as the concentration of radioactive elements,
radiation levels, half-life, and so on. The highly radioactive nature of tritium gives it
the potential to damage cells and tissues with radiation. In the Marine environment,
tritium will be absorbed by organisms and enter the food chain, which will lead to
radiation damage to species in the ecosystem, affecting the reproduction of Marine
organisms and ecological balance.
The diffusion path of radioactive wastewater in seawater is affected by many factors
such as water motion, seabed topography, water depth, tidal and seasonal changes,
and environmental conditions. Understanding the transport and diffusion of
radioactive wastewater in the environment can help us assess the enormous impact on
surrounding Marine ecosystems and human health.
