MINNEAPOLIS (AP) — A German-operated cargo ship and crew have been stuck at anchor outside the Lake Superior port of Duluth for close to a month for unspecified environmental violations, with no resolution in sight despite the upcoming closure of the St. Lawrence Seaway for winter, officials said Wednesday.

The U.S. Coast Guard said the Liberian-flagged Cornelia is being investigated for “alleged violations of U.S. environmental regulations,” and the ship and crew are prohibited from leaving Duluth until they get clearance from U.S. Customs and Border Protection. The Coast Guard can’t say what the alleged violations were because of the ongoing investigation, but they didn’t take place in Duluth, said Petty Officer 3rd Class Christopher Yaw, a spokesman in Cleveland.

Duluth Seaway Port Authority spokeswoman Adele Yorde said such detentions don’t happen very often, perhaps once or twice a year across the Great Lakes system, and they don’t usually take so long to resolve. A complicating factor is the number of companies and countries involved, she said.

The crew of 19 Czechs, Ukrainians, Filipinos and Croatians apparently hasn’t set foot on shore since the Rev. Doug Paulson and volunteers from The Seafarers Center in Duluth took several into town to shop in early November. Paulson said they brought Christmas gift boxes to the crew when the ship arrived. He said they saw Coast Guard officials onboard and knew something was going on, but didn’t know what.

The 576-foot Cornelia loaded grain in early November for a customer in Tunisia, said Paul Gourdeau, executive vice president of Fednav, a Montreal, Canada-based company that chartered the ship and crew to bring it into the Great Lakes with a load of steel and take it back out with the grain. Once that voyage is over, the ship will revert to its owners, a German investment group, he said. He said he can’t comment on the alleged violations or efforts to resolve the dispute.

“We’re like everyone else — waiting here to see when the issue is going to be resolved and when the ship can move on,” Gourdeau said.

The ship is managed overall by the German shipping company MST Mineralien Schiffahrt. Company officials didn’t immediately return a phone call and email seeking comment.

Oceangoing ships typically try to leave Duluth no later than Dec. 18 because of the time it takes to transit the Great Lakes before the St. Lawrence Seaway closes for the season, Yorde said. A key gateway, the Welland Canal between Lake Erie and Lake Ontario, is scheduled to close Dec. 26 but will remain open through Dec. 30 ice conditions permitting, the seaway authority says.

The crew could be in for “a long winter’s nap” without a resolution, Yorde said.

“They’re getting a great view of the hillside,” Yorde said, referring to the tall hills overlooking the port. “I’m sure they’re getting a little tired of the view.”

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