In 1954, a gas-producing plant closed near the Congaree River in Columbia, SC. But its presence lingers, in the form of roughly 40,000 tons of "taffy-like" black tar that need to be removed from the river.

The State reports on a most unusual side effect of damming the river to do so: the possible recovery of Confederate munitions seized and then dumped by Gen.

William T. Sherman's Union army a century and a half ago. The State includes a list of what Union troops logged as having captured from their Confederate counterparts in taking the city on Feb. 17, 1865: 1.2 million ball cartridges, 100,000 percussion caps, 4,000 bayonet scabbards, 3,100 sabers, 1,100 knapsacks, and more.

Whatever they didn't bring with them as they marched toward North Carolina they dumped in the Congaree to keep it out of Confederate hands. The energy company SCANA Corp. will facilitate the Congaree cleanup, which involves exposing about 15 acres of riverbed and removing a tar cap that's, on average, 2 feet thick—along with any Civil War artifacts, which a separate State article notes would belong to the state.

While the company's director of environmental services says "we don't have any direct knowledge of ordnance," the State points out he also didn't deny the findings of a September draft report SCANA commissioned that involved the use of sonar and metal detectors.

That report identified 218 sites as "exhibiting signature characteristics that could be associated with ordnance." Though items have been documented as being salvaged in the 1930s, 1970s, and 1980s, the state's underwater archaeologist isn't expecting a mass cache to surface this time around.

"I'm sure there will be some interesting items. I don't anticipate huge volumes," he says. (An "underwater Pompeii" was recently discovered off Greece.)

This article originally appeared on Newser: Gen. Sherman's War Spoils May Sit at Bottom of SC River

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