Local officials and citizens from southeastern Minnesota pleaded at the Capitol Tuesday for state help to halt the expansion of industrial frac sand mining until more is known about the industry’s effects on air, water and public health.

During two and a half hours of public testimony at an overflowing joint Senate and House hearing, lawmakers heard a drumbeat of calls for a moratorium and statewide environmental impact review — but also assurances from industry officials that Minnesota already regulates sand mining with a far-reaching hand.

“We think the state is well situated to impose conditions on permits already,” said Mike Caron, a spokesman for Tiller Corp., an aggregate and frac sand company that recently helped form the Minnesota Industrial Sand Council.

When the informational hearing concluded, Sen. John Marty, who chaired the session, said it’s clear that county boards, city councils and township supervisors want help in deciding how extensively to regulate the industry before major projects are “rammed through.” Some officials said they also want the state to set air-quality standards to control dust concentrations in the ambient air.

“We heard from lots of local government officials who were saying, ‘We don’t have the expertise,’ ” said Marty, DFL-Roseville. “The point is, we need to learn more.”

No legislation was introduced at Tuesday’s hearing, but Marty said in an interview that a moratorium might provide the breathing room necessary for the correct level of state involvement. “Let’s be fair to both sides,” he said. “It [a moratorium] is not meant to punish the industry. It’s for fact finding.”

Among state agency officials who testified, Aggie Leitheiser, assistant commissioner of the Minnesota Department of Health, said the agency is poised to provide guidance later this year on exposure limits for airborne crystalline silica, a known carcinogen that also can cause asthma and silicosis, a lung disease.

She said the state can’t currently answer questions from local units of government about a variety of air and water pollutants germane to frac sand mining and processing.

“Information on some of those areas is definitely lacking,” she said.

Houston County’s Board of Commissioners, the Red Wing City Council, a city councilor from Wabasha and elected township officials from Fillmore and Goodhue counties all voiced support for more state study and a moratorium on the permitting of new frac sand mines and facilities.

Kelley Stanage, a member of the Houston County Frac Sand Study Committee, said Minnesota should set itself apart from Wisconsin, where nearly 100 frac sand mines, processing facilities and transportation hubs have been permitted in the past four years. In both states, frac sand mining is currently controlled at the county, township and city levels, with some additional permitting by the state.

Patricia Popple, an activist from Chippewa Falls, Wis., said noise, traffic, sand and waste spills into waterways, crumbling roads and illness blamed on fugitive dust have become hot issues in her state.

“We cannot let this happen in Minnesota,” Stanage said.

Kirsten Pauley of the Minnesota Industrial Sand Council said Minnesota has decades of experience regulating limestone, gravel, rock and industrial sand. She said her group supports voluntary air monitoring, noting that existing permits can be reopened by the state for adjustments. But she spoke against re-regulation of an industry that already works to control its dust as standard operating procedure.

Tony Kwilas of the Minnesota Chamber of Commerce urged legislators to be careful about any regulation that would dampen job growth in the industry. For every mining job in the Mankato area, for instance, another 1.8 jobs are created in the local service economy, he said.

“This is already one of the most heavily regulated industries in the state,” Kwilas said.