(CNN) -- In the morning hours of April 21, 2010, Arleen Weise got a phone call from her son's friend, telling her that an explosion had ripped through the Gulf of Mexico oil rig where her 24-year-old had been working.
The Texas native quickly hung up and phoned the rig's owner, Transocean, which leased the drilling rig to BP, in a frantic attempt to find out what happened.
She learned that her son, Adam, was one of 11 workers killed the night before.
"That was it," said his mother. "That was the start of hell."
For the next two years, the 59-year-old hair dresser would go in and out of counseling to cope with her grief, while leaning on family and her customers for emotional support.
"I knew all along that BP was the devil in that accident," Weise said. "Now they're getting their due."
On Thursday, the Justice Department announced that London-based BP will pay a record fine to settle criminal claims in the ensuing catastrophe. The firm agreed to shell out $4.5 billion in government penalties and plead guilty to a dozen felony charges after the April 20, 2010 explosion aboard the Deepwater Horizon rig led to the largest oil spill in U.S. history.
Billy Anderson also lost his son, Jason, in the blast.
This settlement "doesn't bring my boy back, but it does show everybody that they're guilty and everybody knows it," he said.
And yet for many who lost loved ones, Thursday's announcement offered what they described as only a limited sense of justice.
"It doesn't matter how much money anyone pays. It doesn't nearly amount to what we've lost," said Weise.
A statement from BP's CEO apologized for the company's role in the disaster.
"All of us at BP deeply regret the tragic loss of life caused by the Deepwater Horizon accident as well as the impact of the spill on the Gulf coast region," said the statement from Bob Dudley. "From the outset, we stepped up by responding to the spill, paying legitimate claims and funding restoration efforts in the Gulf."
"We apologize for our role in the accident, and as today's resolution with the U.S. government further reflects, we have accepted responsibility for our actions," he added.
The loss of life was only one part of the disaster.
Millions of barrels of oil flowed from the BP well and into the Gulf region, where coastal businesses rely heavily on the seafood industry.
"It made the prices of oysters and shrimp go up," said 41-year-old Denny Amato, part of family that owns Mother's restaurant in downtown New Orleans. "I think people have now come back to eating Louisiana seafood. It just took them a while."
Amato said he and other local restaurant owners are "trying to figure out if there's a way to file a claim."
"I'm just not really sure what's going to happen now," he said.
Louisiana's wetlands represent about 40% of the wetlands in the continental United States, prompting major environmental concerns for such a vast and ecologically diverse area. The oil leak was finally capped in July 2010, nearly three months after it started.
Thursday's landmark settlement is now subject to federal judicial review.
BP posted a $17.2 billion loss in the quarter when the explosion took place, but has been profitable since, tallying total profits of $43 billion over the course of the subsequent nine quarters.