Mississippi environmental regulators have approved an air pollution permit for what could be the largest wood pellet plant in the world, despite objections from environmental groups that the plant would emit too much pollution and have other harmful effects.

The state Environmental Quality Permit Board voted unanimously to issue a permit Tuesday for Enviva Partners LP’s $140 million plant in Lucedale. The company also plans a $60 million ship-loading facility in Pascagoula. The two plants are supposed to have 120 direct employees, with as many as 300 loggers and truckers also finding work supplying Enviva.

The Bethesda, Maryland, company plans to export the pellets to European and Asian utilities, which burn them the generate electricity in place of coal, seeking to reduce emissions of climate-changing carbon dioxide.

“We are pleased with today’s positive outcome and look forward to starting construction of our new wood pellet facility in Lucedale,” Yana Kravtsova, Enviva’s vice president of environmental affairs, said in a statement.

Opponents, though, raised questions about the pollutants and dust the plant would release, as well as its effect on forests. They also questioned whether burning wood pellets instead of coal actually reduces greenhouse gases.

“The Enviva Lucedale wood pellet plant will have a disastrous effect on the people, wildlife, and climate of Mississippi and it is therefore time for the MDEQ board to listen to the people of Mississippi not just rich, powerful industries,” a group of opponents said in a joint statement.

State and local officials have pledged what could be $17 million in aid and tax breaks over the next 10 years, touting the effect on a forestry industry that has been depressed since paper mills in the region closed.

Opponents could choose to challenge the approval by asking for an evidentiary hearing before the permit board. They put an unusual amount of effort into fighting the plant, with the nonprofit Environmental Integrity Project filing a detailed challenge of the permit that included a model showing emissions would exceed the state’s standards for toxic air pollutants.

“Air quality modeling shows that even with the revised permit, air pollution from the plant will be in violation of federal ambient air quality standards,” opponents said their statement.

Mississippi Department of Environmental Quality staff, though, wrote that the air modeling by the nonprofit didn’t follow Mississippi’s rules and thus “is inconclusive regarding Enviva’s impact.” The department said Enviva’s own air modeling also didn’t follow rules and was also inconclusive.

The department said that it had imposed limits on emissions, meeting state rules, and that carbon monoxide and nitrogen oxide emissions had been held within standards preventing serious deterioration. The department also slightly modified its testing rules in response to objections and said that it changed Enviva’s permit to make sure rules against drifting dust can be enforced.

The department wrote that it was aware of problems at other plants and imposed stricter requirements “that we believe will be protective of human health and the environment in Mississippi and will better reflect the facility emissions.”

Opponents also complained that the permit board didn’t take additional public comments Tuesday, with the board chairman ruling the comments would mostly duplicate testimony from an earlier public hearing in Lucedale.

“All the people have is their voice, and they were denied even that at this hearing,” opponents’ statement said.