(Adds background about explosions at Arkema, details from letter, byline)
HOUSTON, Sept 11 (Reuters) - The U.S. Environmental Protection Agency is investigating whether chemical maker Arkema SA followed safety rules at its Crosby, Texas, plant, where several chemical containers caught fire after flooding from Hurricane Harvey, an EPA official said on Monday.
The EPA sent Arkema a letter asking for information that would help the agency determine whether the plant had followed chemical accident prevention rules and other parts of the Clean Air Act, according to a copy of the letter that was provided to Reuters by the EPA official, who did not want to be named.
Containers holding volatile organic chemicals began to burn on Aug. 31, after flooding from Harvey knocked out power to the plant. Arkema's North America chief executive warned a day earlier there was no way to prevent the chemicals from igniting after the plant's cooling systems stopped operating and its workers evacuated.
An Arkema spokesman did not immediately respond to a request for comment.
The Sept. 7 letter, from the EPA's Enforcement Division director, Cheryl Seager, said the company had 10 days after receiving it to comply with the agency's request.
"EPA may use any information submitted in response to this request in an administrative, civil or criminal action," Seager wrote.
Police and firefighters who responded to the Crosby plant fires are suing Arkema in a Texas county court, claiming negligence led to the fires and caused the first responders "serious bodily injuries" when they inhaled smoke.
The first responders filed their lawsuit the same day that Seager sent her letter.
"We deeply regret that anyone suffered harm as a result of the havoc wreaked on our plant by Hurricane Harvey," the company said in a statement in response to the lawsuit. (Reporting by Emily Flitter; Editing by Andrew Hay and Leslie Adler)