COLUMBIA, S.C. (AP) — A private utility should reconsider its decision to leave century-old coal tar at the bottom of a South Carolina river because its statements about the cleanup were misleading, state and federal officials said.

In a letter last month to South Carolina Electric & Gas, the Army Corps of Engineers said it never concluded that the tar couldn't be scraped off the bottom of the Congaree River, according to a letter also signed by the state Department of Health and Environmental Control.

SCE&G suggested covering the coal tar with a fabric held on the river bottom with stones instead after saying the Corps wouldn't issue a permit to allow the company to dam the river near downtown Columbia so the coal tar could be scraped off the bottom.

Environmental officials want to meet with SCE&G and the Corps to discuss plans to deal with the tar again, according to documents obtained by The State newspaper and the Congaree Riverkeeper conservation group, which has threatened to sue if the fabric plan moves forward.

The coal tar was deposited in the river in the early 1900s by a plant that used coal to make gas for cooking.

SCE&G said in November that repeated testing of water quality found the river safe for recreational use. The utility also said the capping process with the fabric had been used many times before and the site would be closely monitored. It also could cost around $11 million less than removing the tar.

Congaree Riverkeeper Bill Stangler said his group will continue to push for the removal of the tar, which was discovered seeping out of sediment along the river bottom by a kayaker eight years ago.