Hello!
The amount of dissolved oxygen in the Missouri River would decrease if large amounts of chemical waste were dumped into it.
This is related to the Biological Oxygen Demand (BOD), which is the amount of oxygen required by microorganisms in the water to process and use chemical waste as food. When chemical waste is added to the water, microorganisms require more oxygen to process this waste and the amount of dissolved oxygen decreases. The Biological Oxygen Demand is used to determine whether wastewater is contaminated or not because as there is more contamination, the Biological Oxygen Demand is higher.
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