Soo Locks delays midnight closure for freighter loaded with 70K tons of taconite Updated Jan 16, 2021; Posted Jan 16, 2021 The Walter J. McCarthy Jr. arrived at the Poe Lock in the Soo early on Jan. 16, 2021. Facebook Share SAULT STE. MARIE, MI - The U.S. Army Corps of Engineers had planned to close the Soo Locks system to all ship traffic at 11:59 p.m. on Friday, Jan. 15, kicking off the annual 10-week season of winter maintenance. But when you’ve got a 1,000-foot freighter motoring across Lake Superior loaded with 70,107 tons of taconite that needs to get to Gary, Indiana, you leave the locks open for a few more hours.