MINNEAPOLIS — Critics of silica sand mining had hoped the Minnesota Legislature would adopt aggressive statewide rules to protect people and the environment. What finally emerged from the just-completed session, however, was a compromise that still leaves key decisions up to local governments.

The sand in the bluffs and hills of southeastern Minnesota and western Wisconsin has been in high demand for hydraulic fracturing, or fracking, the new technology unlocking vast new deposits of oil and natural gas in North Dakota and elsewhere. But opponents have worried about environmental and health effects from mining.

They first sought a statewide moratorium on new projects but gained little traction. Then they pushed for legislation to require new sand mines be located at least a mile from any designated trout stream, which might have put the brakes on many potential projects in southeastern Minnesota. But they couldn’t get that proposal out of committee.

In the end, they settled for a requirement that new mines get a permit from the state to locate within a mile of trout streams after the potential effects on water quality are studied. They also got the state more involved in the environmental review process and in providing model regulations and technical aid to local governments that choose to take advantage of the help.

They also got the authority for local governments to extend their moratoriums against new projects until March 2015.

“I think this is going to work,” said Sen. Matt Schmit, DFL-Red Wing, who was instrumental in forging the compromise and getting it attached to a larger environment bill. He said it will empower local governments by bringing state government expertise to the table that had been lacking before.

But much will depend on how state agencies implement the new rules and whether they set enforceable standards, said Bobby King, an organizer with the Land Stewardship Project, a group that advocates for grassroots local control. It will be up to the Department of Natural Resources to issue permits for mines near trout streams.

“If the DNR really puts protecting the water ahead of allowing mines this could be very helpful. But we’re just going to have to see how they implement it,” King said.

Likewise, King noted, the Minnesota Pollution Control Agency is being directed to develop regulations for controlling silica dust from mines and from processing, storage and transportation facilities. He said the MPCA should set enforceable standards that allow the agency to shut down an operation that violates them. The legislation gives the MPCA the authority to do that but doesn’t mandate it, he said.

The legislation also directs the Environmental Quality Board to develop model ordinances for regulating silica sand facilities, though it will be up to townships, cities and counties to decide whether to implement them. The EQB also will assemble a technical assistance team that will work with local governments that ask for help.

The optional help for local governments is good, said Tony Kwilas, a lobbyist with the Minnesota Chamber of Commerce. But he said the permit requirement for operations near trout streams “sends a dangerous message to the business community” by singling out the sand industry for special regulations that won’t apply to other operations. He said the state’s existing rules and regulations are sufficient for protecting the environment and tourism while allowing for economic development.

Even with the protections for trout streams the legislation still gives the sand industry plenty of opportunities for mining, said Steve Morse, executive director of the Minnesota Environmental Partnership, a coalition of more than 75 environmental and conservation organizations.

“Sand mining can move forward but we’re going to be very careful in how and when it happens,” Schmit said.