In the run-up to the fifth anniversary on Monday of one of the worst environmental disasters in American history, the 2010 BP oil blowout in the Gulf of Mexico, the country has heard happy talk from the company most responsible for it. Using phrases like “returning to pre-spill” or “baseline” conditions, and by emphasizing a rebound in fishing and tourism, BP has been suggesting in its reports and advertising that recovery of the entire ecosystem is just around the corner.

It is not. While much of the oil has evaporated, been consumed by bacteria or widely dispersed, its poisons linger in marshes and wetlands, deep-sea corals are visibly damaged, and scientists have estimated that millions of gallons settled in roughly 1,200 square miles of the ocean floor, with untold consequences for the health of bottom-dwelling organisms.

An official federal-state natural resource assessment, mandated by the Oil Pollution Act, is still far from complete. In the meantime, it is impossible to say what the long-term effects will be on individual species like bluefin tuna, dolphins and pelicans. As the officials in charge of that study have said, “The environmental effects of this spill are likely to last for generations.”

Amazingly, though, this calamity yielded two benefits. One was an overhaul of federal oversight of offshore drilling, which for decades had been distinguished mainly by the cozy relationship between industry and its regulators. The interior secretary, Sally Jewell, building upon internal reforms begun by her predecessor, Ken Salazar, recently proposed tough rules mandating updated control equipment and blowout prevention technologies.

It is hard to forget the flailing efforts by both industry and government to stop the runaway well in 2010, including the failure of the blowout preventer and the preposterous “junk shot” attempt to jam golf balls and shredded tires down the gushing well. New rules will be crucial going forward, especially in inhospitable environments like the Arctic and as oil companies move further and further offshore to deeper, higher pressure waters. It would be foolish to assume that another disaster won’t happen. But surely it’s possible to be better prepared for it.

Another benefit, requiring follow-through, is that the penalties BP will have to pay in restoration money may finally give the gulf’s fragile ecosystem the long-term care it needs, especially its wetlands and barrier islands. Over the years, oil and gas companies have sliced and diced Louisiana’s forests, coastal marshes and mangrove swamps with more than 10,000 miles of canals. This, combined with years of misguided flood control along the Mississippi River, has already cost Louisiana 2,300 square miles of wetlands, with more erosion every day.

BP has already shelled out just over $30 billion, mostly in cleanup costs, damage claims from individuals and businesses and about $700 million in early restoration projects. But more will be arriving: several billion for natural resources damages, and as much as $13 billion in penalties under the Clean Water Act for the 3.19 million barrels of oil that a federal judge in New Orleans has now determined BP discharged into the gulf.

The task for federal and state officials will be to make sure that these funds are applied to replenishment of beaches, dunes, wetlands, oyster beds and the like, and not diverted to politically inspired development projects that have little connection to environmental needs.