CANADYS — South Carolina Electric & Gas continues to seek state permits for a huge dry coal ash dump on the Edisto River, despite announced plans to convert the coal-fired plant here to natural gas.

Plant facts

10 to 197: Range of acres for a typical dry coal ash landfill.80: Acres of the proposed Canadys landfill.100: Tons of waste ash currently produced per year at Canadys.2012: Year the first of three coal-fired boilers shuts down.2015: Year the last two boilers shut down.Environmental Protection Agency, SCE&G

The move worries Dorchester County residents who heatedly opposed the dump after Colleton County rejected plans for a similar landfill on their side of the river.

For the people who live in the rural upper county, the slow-rolling Edisto is the life to the place.

They are concerned that the dump will take the pollutant-laced ash from other plants, further threatening the river and rural environment.

An SCE&G spokesman said the company will not do that.

“That will not happen,” said Robert Yanity, public affairs supervisor. “The landfill is sited and permitted only for Canadys ash.”

The company has not applied for that specific permit yet. The permit could allow the landfill to take ash from other SCE&G facilities, if requested and approved, said Adam Myrick of the S.C. Department of Health and Environmental Control. But it would not allow coal ash from another company.

Yanity said the landfill still is needed because conversion plans call for the Canadys plant to coal-fire two of three boilers until 2015; the landfill also would take ash to be removed from current riverside “wet” ash pits.

“There is no need for us to bring ash from other facilities,” Yanity said, because those facilities have their own dry ash landfills.

Plans call for an 80-acre landfill on a 100-acre site, holding stacks potentially as high as 100 feet.

It is too early to say if the size of the landfill will be scaled down, Yanity said.

The wet pits have a history of leaching into the groundwater and on at least one occasion breaching into the Edisto. Dry ash landfills are considered safer than wet because they less likely to leak or fail; the new landfill would be lined.

“It’s better to get the ponds cleaned up. Maybe it will allow us to begin the process of reclaiming the Edisto. That would be good for Dorchester County, good for the people who live along the river,” said Pete Weathers of St. George.

“But I’d hate to see them take ash from other plants. I don’t know what they’d do with it except leave it piled up.”

The 50-year-old Canadys plant is SCE&G’s oldest and smallest coal-fired electric plant.

The natural gas conversion, announced in May, was driven by the cost of adding pollution-cleaning equipment to meet new federal regulations, company officials said then.

Coal-fired plants have been criticized by environmental advocates for pollutant discharges that include mercury. They say the plants are given leeway by regulators because of the critical need for electricity.

In early 2011, SCE&G proposed to open a 160-acre dry ash pit in Colleton County about five miles away from the plant and the current across-the-river dump site.

That landfill potentially could have stacked dry ash 15 stories high. Resident opposition derailed the zoning permit, and the company turned its attention to the new site.

Dorchester County Council rejected a zoning change for that site, then reversed its vote after meeting with company officials.

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