CF Industries Holdings Inc. will pay a $701,500 civil penalty and spend $12 million to improve handling of hazardous waste at a Florida fertilizer plant.

The company said Friday that additional spending might be needed in future years.

Federal officials say it could cost $163.5 million to clean and close the site in Plant City, Fla., after its useful life ends. The company has put half that amount in a trust fund, including a $55 million contribution as part of the consent decree announced Friday.

CF Industries said it reached the agreement with the U.S. Environmental Protection Agency and the Florida Department of Environmental Protection over allegations raised in 2005 about the phosphate facility.

The Justice Department said federal and state inspectors found the company was disposing of hazardous waste in ponds without a permit and violating federal law on handling of the waste.

The company said it didn't admit to violating the law.

The consent decree needs approval by a federal court.

CF Industries makes nitrogen and phosphate fertilizer for agricultural and industrial users. The EPA has focused on makers of phosphoric acid because of the risk it can contaminate groundwater and kill fish.

CF shares fell $1.51 to $84.29 in afternoon trading.