A barge loaded with two-story steel boxes shot through with pipes and wrapped in walkways with safety yellow railings departed Cianbro's Eastern Manufacturing Facility in Brewer March 7, pulled by a Louisiana-based tug and guided at the stern by a smaller Belfast-based tug.

This marine conga line motored down the Penobscot River, attracting a few spectators and at least one drone photographer on its way to the bay and points south. As of March 15, the tug and barge were traveling along the Florida Keys.

A Cianbro spokeswoman, citing an agreement with the client, would not disclose any information about the destination of the shipment or the nature of the equipment, which has been described in numerous published news reports as refinery modules.

According to one local source, the shipment is headed to the Gulf of Mexico and ultimately to a refinery in the Midwest.

Cianbro imported four shiploads of prefabricated steel components from Thailand last year through the marine terminal in Searsport. The spokeswoman declined to say whether those were used in the latest shipment of modules.

Cianbro has done similar prefabrication projects in the past, including modules for the Motiva Enterprises crude oil refinery in Port Arthur, Texas, in 2009 and electrical rooms for the Vale Newfoundland and Labrador nickel processing plant in Long Harbour, Newfoundland, in 2011.