HARLEYVILLE -- A plant that burns nearly 300,000 tons of wood per year, with a smokestack rising out of the Dorchester County countryside smack between cement plants that rank among the bigger air polluters in the Lowcountry. The stuff of an environmental horror, right? Not quite, in the eyes of most local leaders.

Construction is expected to start in the next few weeks on the $46 million "biomass" plant generating electricity by burning logging debris. The Southeast Renewable Energy plant near Harleyville is considered part of the new wave of "green energy." It's been embraced by county leaders, state and federal environmental regulators, and even environmental advocates.

Why? Fossil fuels. Compared to the air pollution concerns from large power plants burning coal, a small plant burning a renewable resource like wood is considered the lesser of two evils.

Few nearby residents have paid much mind to the plans, said Jimmy McDonald of Harleyville. The plant would be within a mile of the town. His concern is more with keeping the company to its agreement to burn only logging wood and making sure air-emission cleaning equipment operates as it should.

"It comes down to money and convenience," he said. "The positive part, it's good for (providing) electricity."

County leaders have signed on big-time to the plant and its expected 20 jobs. They have given fee-in-lieu-of tax incentives and contracted to supply the plant with 20 tons per year of debris wood from county operations. County Council Chairman Larry Hargett has championed it as a money-saver worth some $300,000 each year.

The federal Environmental Protection Agency has proposed rules that exempt operations like the SRE plant from limits on carbon dioxide, a "greenhouse gas" considered a chief contributor to climate warming, and a major emission from the plants. State regulators are following the federal lead.

The Lowcountry environmental advocate Coastal Conservation League is part of a lawsuit challenging the EPA exemption. If the plant's projected carbon dioxide emissions weren't exempted, "the plant would qualify as a major emitter rather than a minor emitter, and they would face much tighter restrictions on their hazardous air pollutants," said Ryan Black, energy and climate project manager.

But the league isn't challenging the plant. Its staffers wrote to the state to support an SRE plant being built in Allendale, promoting "small-scale sustainable biomass facilities for electricity generation as a means to invigorate our state's working rural landscapes and to reduce our dependence on imported energy resources such as coal or uranium."

The league's comments on the Allendale plant did raise concerns, which the S.C. Department of Health and Environmental Control apparently took into account when issuing the Harleyville plant permits, Black said. The Harleyville plant is permitted to burn clean, untreated wood, and prohibited from burning yard, construction or demolition waste.

Santee Cooper, the Moncks Corner-based utility faced with closing two of its smaller coal-burning plants because of new EPA air pollution rules, plans to buy power from the plant.

The plant must use control devices that keep pollution at levels considered safe even for people with chronic respiratory problems, said Raine Cotton, SRE president.

"There are groups that don't agree with the EPA exemption for biomass," Cotton said. "But if we didn't utilize (logging residue) it would be left to sit and rot in the field, which would release carbon dioxide, or more often would be pushed in a pile and burned, releasing even more pollution than controlled equipment."

The plant plans to burn 288,000 tons of residue per year. State logging operations produce about 20 million tons per year, he said. "Just the county of Dorchester alone produces more residue than we can use."

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