• Air: Mines and processing plants need air permits. Silica exposure is a public health concern, and stray dust has been a source of complaints, so DNR has been sending information to mine operators on how to control it.
• Water: All mines need a stormwater permit. Those using a lot of water need a high-capacity well permit. And if they’re near wetlands or surface waters, other DNR regulations may apply.
• Local regulations. Local governments exert control through zoning, but many mines are in towns that don’t have zoning. Where there is zoning, towns can regulate issues like hours of operation, truck routes and speeds, covering of truck beds, mine depth and road repair liability.
• Reclamation. Mines have to abide by NR 135, the nonmetallic mining reclamation rule. It’s administered by the counties with DNR oversight.
— Adapted from DNR memorandum, January 2012