Various states have pretty strict (including criminal laws) re littering and securing loads on vehicles. Montana does not.

Linked are some examples that mostly apply to vehicles on highways but some apply to trains. Montana doesn't seem to have rules for trains, and even for trucks carrying agricultural produce and fertilizer seem to be exempt from littering laws.

There are also environmental protection laws that may apply.

So this seems like an issue that could be prevented by introducing littering laws / secure loads that apply in other states.

https://www.pulltarps.com/wp-content/uploads/2019/08/WhitePa...