You may need a MI stormwater permit if you are storing salt. MI DEQ may also have rules that regulate deicing with salt for sensitive watersheds.
MI has salt guidelines for small snow removal operations: http://www.deq.state.mi.us/documents/deq-ess-p2tas-commercialsaltguidance.pdf
The state has salt deicing regulations at Part 5, 324.2001 to 324.2009.
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