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The wartime Hanford reactors did not produce any electricity. They had no safety containment systems. And they released cooling water containing radioactive contamination directly into the Columbia River: https://www.osti.gov/opennet/manhattan-project-history/Proce... Aside from "possible catastrophes" involving control rod failures, enemy bombing, or sabotage, DuPont's greatest concerns about reactor operations involved pumping Columbia River water through the reactors for cooling purposes. Using a "once-through" system, water was taken from the river and chemically treated before passing through the core of the reactor at the rate of 75,000 gallons per minute and being released back into the river. The reactor used canned fuel slugs, which prevented radioactive fuel from getting into the coolant as long as the cans did not accidentally rupture. Even if no fuel escaped, however, there was induced radioactivity of the impurities and treatment chemicals within the water. Radioactivity thus inevitably entered the Columbia. To alleviate possible dangers, DuPont engineers diverted the heated and "somewhat radioactive" exit water, containing mostly, but not exclusively, short-lived radionuclides, as well as certain chemical contaminants, to a 12,000,000 gallon retention basin. Each basin was divided in two, with the two sides operating in parallel. Monitoring for radioactivity occurred at the inlet to the basin, at an intermediate point, and at the exit. After six hours, radioactivity diminished by a factor of about twenty. With radioactivity below the then tolerance dose for complete immersion, the water was further diluted with wastewater free from radioactivity and returned via underground pipes for release in mid-river. |