All of the rivers in the United States are not monitored closely for pollution levels.
The statement in the question is False
Step-by-step explanation:
Not all rivers in the United States are closely monitored for their pollution levels. There are volunteers who take responsibility of checking water bodies such as lakes, rivers, streams etc. They take the next step required after finding a water body contaminated.
But to say that all the rivers receive the same amount of attention and action is incorrect. To ensure that all the rivers are clean and pollution free, it would require a lot of man power in the said department which would collect the water samples from all these rivers and send it to labs for checking the pollution level of the particular river. It can be said that the rivers which are situated beside an industrial site, close to a town, will be the priority for checking pollution levels as it would directly cause harm to a small set of population if the toxicity is at an increased level.