The U.S. Coast Guard and Ohio Environmental Protection Agency are finalizing plans to remove the remaining petroleum product from the sunken tank barge Argo in Lake Erie, but need to bring in equipment from outside the region in order to complete the work.

Product samples taken from the barge last week were found to be primarily benzene, with some toluene, xylene and trace elements of petroleum, the Coast Guard said. The exact contents of the barge’s cargo have been lost to history, but she was estimated to be carrying about 100,000 gals. of both crude oil and benzol when she sank in 1937 near Kelleys Island, Ohio.

Because these materials are not typically shipped on the Great Lakes — the Great Lakes Historical Society said the barge was operating illegally on the lake when it sank — the proper equipment to remove the product is not locally available and response operators are waiting for specially modified receiving tanks to offload the product.

In the meantime, response crews will begin prepping the first tank aboard the Argo for lightering operations that may begin later this week, the Coast Guard said. In addition to equipment-related delays, the operation has been hampered by weather.

The safety zone around the barge remains at a one nautical mile radius directly above the barge’s location at the bottom of Lake Erie.