WASHINGTON (AP) — Norfolk Southern’s CEO is apologizing to Congress on Thursday and pledging millions of dollars to help East Palestine, Ohio, recover from the fiery hazardous materials train derailment as senators investigate rail safety and the Biden administration’s response to the disaster.

“I am deeply sorry for the impact this derailment has had on the people of East Palestine and surrounding communities, and I am determined to make it right,” CEO Alan Shaw said in prepared remarks released ahead of the Senate Environment and Public Works panel hearing.

Shaw says the railroad will do “the right thing” with a $20 million commitment to help the community recover.

The company has announced several voluntary safety upgrades. Senators, however, have promised a pressing inquiry into the derailment, the company’s safety practices and the emergency response to the toppling of 38 railcars, including 11 carrying hazardous materials. Federal regulators have also said Norfolk Southern must do more to improve safety.

No one was injured in the crash, but state and local officials decided to release and burn toxic vinyl chloride from five tanker cars, prompting the evacuation of half of the roughly 5,000 residents of East Palestine. Scenes of billowing smoke above the village, alongside outcry from residents that they are still suffering from illnesses, have turned high-level attention to railroad safety and how dangerous materials are transported.

“I want to hear what did they do wrong, what mistakes did they make,” said Sen. Tom Carper, D-Del., the chair of the committee. “There’s been a number of criticisms of what they did, and to have him respond to those criticisms on the record.”

Carper joined the top Republican on the committee, Sen. Shelley Capito of West Virginia, in a call with reporters on Wednesday to emphasize they would work in bipartisan fashion “to deliver accountability to the communities and folks who have been impacted.”

The East Palestine disaster as well as a spate of other recent train derailments have sparked a show of bipartisanship in the Senate. The committee on Thursday will also hear from Ohio and Pennsylvania senators — Republican JD Vance and Democrats Sherrod Brown and Bob Casey — who are pushing new safety regulations called the Railway Safety Act of 2023.

“It shouldn’t take a train derailment for elected officials to put partisanship aside and work together for the people we serve – not corporations like Norfolk Southern,” Brown said in prepared remarks. “Lobbyists for the rail companies spent years fighting every effort to strengthen rules to make our trains and rail lines safer. Now Ohioans are paying the price.”

Train derailments have been getting less common but there were still more than 1,000 last year, according to data collected by the Federal Railroad Administration. But even a single train derailment involving hazardous materials can be disastrous.

Noting that a train had derailed in her home state of West Virginia on Wednesday, Capito cast the hearing as the Senate’s first step among several on railway safety and emergency response.

Hazardous materials shipments account for 7% to 8% of the roughly 30 million shipments railroads deliver across the U.S. each year. But railroads often mix shipments and might have one or two cars of hazardous materials on almost any train.

The Association of American Railroads trade group says 99.9% of hazardous materials shipments reach their destinations safely, and railroads are generally regarded as the safest option to transport dangerous chemicals across land.

But lawmakers want to make railroads safer. The Railway Safety Act of 2023, which has gained support from Senate Majority Leader Chuck Schumer, D-N.Y., would require more detectors to be installed to check the temperature of wheel bearings more frequently, make sure railroads notify states about the hazardous materials they are transporting, and fund hazmat training for first responders.

Meanwhile, House Republicans have voiced skepticism about passing new regulations on railroads. GOP senators discussed the bill in their weekly luncheon on Tuesday, but Sen. Mike Rounds, R-S.D., said most would prefer the bill be ironed out in a committee.

Norfolk Southern is also under pressure from federal regulators. The National Transportation Safety Board and Federal Railroad Administration both announced investigations this week into the company’s safety culture. The NTSB said its investigators will look into five significant accidents involving Norfolk Southern since December 2021.

The company has said it is immediately implementing safety upgrades, including adding “approximately 200 hot bearing detectors” to its network. The NTSB has said a detector warned the crew operating the train that derailed Feb. 3 outside East Palestine, but they couldn’t stop the train before more than three dozen cars came off the tracks and caught fire.

Republican Sen. Vance of Ohio pointed to those voluntary steps as a sign his bill was “on the right track.” But Democratic sponsors of the legislation have said regulations should require operators to go further.

The Senate bill also touches on a disagreement between railroad worker unions and operators by requiring train crews to continue to have two people. Unions argue that railroads are riskier because of job cuts in the industry over the past six years. Nearly one-third of all rail jobs were eliminated and train crews, they say, deal with fatigue because they are on call night and day.

Republicans, at the same time, are more eager to delve into the emergency response to the East Palestine derailment. Thursday’s Senate hearing also features environmental protection officials from the federal, state and local levels.

Capito said President Joe Biden should have visited the community in the aftermath of the derailment. The Democratic president has said he will visit at some point. Transportation Secretary Pete Buttigieg went to East Palestine last month and has pressed for increased safety protocols for trains.

Several East Palestine residents were making their way to Washington for Thursday’s hearing, including Misti Allison, who has joined a group called Moms Clean Air Force. Officials have told the town’s residents that air and water tests don’t show any dangerous levels of toxins, but Allison and other residents worry about potential long-term effects.

“Everybody here wants it to be fine. We want that to be true so badly. Everybody loves this community and nobody wants to leave. … But if it’s not, we need to know that,” Allison said.

A chemical odor can still be smelled in East Palestine at times, she said, adding: “Congress must hold accountable Norfolk Southern and these polluters and companies that run these train bombs through neighborhoods like ours.”