In a report filed with the Contra Costa County Health Services Department on Monday, the San Ramon, Calif.-based oil giant said it has paid the money in connection to nearly 24,000 claims from residents and in compensation to area hospitals and local government agencies in Richmond and in Contra Costa County.

Most of the $10 million went to hospitals for medical exams and treatment immediately following the incident, Chevron spokesman Sean Comey said in an email to The Associated Press.

The payments follow a fire in a crude oil unit of the refinery on Aug. 6 that sent a cloud of gas and black smoke over residential areas, prompting thousands of people to seek medical treatment, with many complaining of eye irritation and breathing problems.

Federal investigators have said that Chevron firefighters responding to a small leak at the facility may have accidentally punctured a main pipeline that sparked the massive blaze.

A metallurgical report showed the 40-year-old pipe that failed, causing the leak, was initially weakened by the heavy sulfur content of the crude oil being pumped through it. After a small leak sent hydrocarbons into the air, a small flash fire was put out. But a larger gash in the pipe released a bigger cloud of flammable gas, leading to a larger fire.

Chevron is also strengthening its reliability programs for piping and equipment, updating protocols on how crews respond to new leaks and is increasing employee training, the company said in its report.

The crude oil unit where the fire erupted remains closed as crews work on repairs, but Chevron officials expect to restart the unit by the end of March, Comey said.

Chevron also plans to release the results of the company’s internal investigation before restarting the unit, Comey said.