The Irving Whale was built at the Saint John Shipbuilding & Dry Dock Company in New Brunswick in 1966 and entered service the following year. Owned by J.D. Irving Limited and used exclusively by its sister company Irving Oil, the barge hauled Bunker C fuel oil to industrial customers -- power plants and pulp mills -- across Atlantic Canada. On September 7, 1970, while being towed from Halifax to Bathurst, New Brunswick, the unmanned barge was riding low under the weight of approximately 4.35 million litres of fuel oil. Stormy weather in the Gulf of St. Lawrence turned a routine delivery into a disaster. The tow line was lengthened, the stern submerged, and the barge took a 45-degree list. The crew of the towing vessel Irving Maple radioed continuous updates to the Canadian Coast Guard as they watched the barge founder over the course of three hours. She sank 60 kilometres northeast of North Cape, Prince Edward Island.

The wreck did not stay quietly on the bottom. Oil leaked from the corroding hull, fouling approximately 80 kilometres of shoreline on the nearby Magdalen Islands and seeping steadily into the Atlantic. By the mid-1990s, the CBC was calling the Irving Whale "a pollution timebomb." But raising her presented its own hazards: the PCBs in the barge's heating system could be released during any salvage attempt, potentially contaminating the surrounding waters in a different and more persistent way. Environmental groups filed injunctions to halt the operation. The Federal Court of Canada granted a three-month injunction in August 1995, stopping preparatory work that had already begun on the barge. The recovery was postponed to the summer of 1996, when weather conditions would allow the delicate operation to proceed.

The salvage operation cost $42 million. The question of who should pay for it became one of the most contentious environmental disputes in Canadian history. The Irving companies -- J.D. Irving Ltd., owner of the barge, and Irving Oil, owner of the cargo -- were among the wealthiest business empires in Atlantic Canada. Yet the federal government initially assumed the entire cost. The controversy was immediate and fierce. In 1997, Ottawa sued to recover the $42 million. Daniel Green of the environmental group SVP called it the worst possible precedent for the "polluter pays" principle. The dispute dragged on until 2000, when the Irving companies paid $5 million "without admitting liability" -- a sum that, as later court proceedings revealed, happened to match their decades-old insurance coverage exactly. Canadian taxpayers covered the remaining $33 million.

Perhaps the most remarkable chapter came after the salvage. The Irving Whale was towed to Halifax, where her oil and PCBs were pumped out. The oil was sold. Then the barge itself was refitted, renamed ATL 2701, and returned to active service for the Irving company. The vessel that had spent a quarter-century as a symbol of marine pollution was back hauling cargo in the same waters where she had sunk. The legal battles continued even after the settlement between the Irvings and the government. A dispute between the Irving companies and their insurers over the $5 million payment wound through the courts until 2014, when Justice Sean Harrington ruled in the Irvings' favour. He noted that had the government's case gone to trial instead of settling, the damages could have reached $20 million. The Irving Whale -- now ATL 2701 -- continued working the waters of Atlantic Canada, her past written on no part of her hull.