The United States has stored 212 million liters of radioactive waste in 177 underground tanks at the Hanford site in Washington state. Originally built during World War II, the site was used to produce plutonium for atomic bombs, including those dropped on Nagasaki and Hiroshima in 1945. Hanford operated at full capacity throughout the Cold War until 1987, and today the site covers nearly 1,500 square kilometers—about fifteen times the size of the Lyon metropolitan area in France. The U.S. Department of Energy estimates the decontamination project could be completed by 2078, though the confidence level for this timeline is between 50 and 80 percent, and the timeline is already three times longer than the site’s operational lifespan. At least 68 of the 177 underground tanks have leaked, contaminating groundwater and the nearby Columbia River with radioactive materials such as tritium, chromium, and uranium. Of the 177 tanks, 149 are single-wall structures made of concrete and steel, designed for short-term use but now far past their expected lifespan. The remaining 28 are double-wall tanks, built from 1968 with more robust containment systems. However, one of these double-wall tanks has already developed a leak, and more than 3.8 million liters of radioactive liquid have seeped into the ground, reaching depths of 60 meters before potentially flowing into the Columbia River, about ten kilometers away. Despite awareness of these leaks, authorities have no safe alternative for storing the waste, and the most hazardous materials are being gradually moved to the double-wall tanks, which are considered safer but are running out of space. The primary solution for managing the waste, known as "vitrification," involves mixing the radioactive material with glass powder and melting it to create a stable, non-leaking solid that can remain safe for up to 10,000 years. The project was first launched in the 1990s with a budget of $4 billion and an initial goal of completing the process by 2019. However, delays and rising costs have pushed the current legal deadline to 2052, though the Department of Energy has internally moved the target to 2069, according to a 2021 report by the Government Accountability Office. The budget has also ballooned, from $4 billion to over $30 billion, with projections continuing to rise. Despite these challenges, the site currently employs more than 13,000 people, supported by an annual budget of nearly $3 billion. Efforts to speed up the process have included technological advances such as a cesium pretreatment system, which can process large volumes of waste with a radioactivity removal rate of nearly 99.9 percent. However, these improvements do not address the scale of the problem: millions of liters of radioactive waste, aging tanks, and a nearby river that remains vulnerable to contamination. The decontamination of Hanford is not a project that can be completed within a single generation. It is an ongoing effort that must be passed on to future administrations, as the current workforce may not live to see the project finish. With funding proposals suggesting a reduction in federal support, the challenges of managing this legacy of Cold War nuclear production continue to grow.