Question: How did the train conductors not hear the water pump Walt was using to pump water into the tanker? They were only around 800 feet away in open land, so it should have been audible.
Answer:For one thing the engine running the pump isn't that loud. The characters have conversations at a normal volume without having to scream at each other. Even if the conductors could hear it, there is no reason they should care or be suspicious. It just sounds like an engine running in the distance and they don't care enough to look for what is making the noise. At that very moment there is also a kid riding a dirt bike in the area. Engine noises are a very common thing.
Answer: For one thing the engine running the pump isn't that loud. The characters have conversations at a normal volume without having to scream at each other. Even if the conductors could hear it, there is no reason they should care or be suspicious. It just sounds like an engine running in the distance and they don't care enough to look for what is making the noise. At that very moment there is also a kid riding a dirt bike in the area. Engine noises are a very common thing.
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