(CNN) -- SeaWorld has been fined $75,000 by the Occupational Safety and Health Administration for three safety violations, including one classified as willful, after an animal trainer was killed in February.

In a statement Monday, Cindy Coe, OSHA's regional administrator, said that SeaWorld knew of the inherent risks of allowing trainers to interact with dangerous animals.

"Nonetheless, it required its employees to work within the pool walls, on ledges and on shelves where they were subject to dangerous behavior by the animals," Coe said in the statement.

SeaWorld denied what it called "unfounded" allegations by the U.S. Department of Labor agency and said it would contest the citations.

"OSHA's allegations in this citation are unsupported by any evidence or precedent and reflect a fundamental lack of understanding of the safety requirements associated with marine mammal care penalties," a SeaWorld statement said Monday.

In February, a 12,000-pound killer whale at the Orlando, Florida, SeaWorld pulled trainer Dawn Brancheau, 40, underwater and killed her as horrified park visitors watched. An autopsy report showed Brancheau died from drowning and traumatic injuries to her body, including her spine, ribs and head.

The OSHA statement said the whale involved was one of three also involved in the death of an animal trainer in 1991 at a Vancouver, British Columbia, water park.

The agency's investigation "revealed that SeaWorld trainers had an extensive history of unexpected and potentially dangerous incidents involving killer whales at its various facilities, including its location in Orlando," the OSHA statement said. "Despite this record, management failed to make meaningful changes to improve the safety of the work environment for its employees."

OSHA issued one "willful" citation -- defined as a violation committed with plain indifference or intentional disregard for employee safety health -- for "exposing its employees to hazards when interacting with killer whales," the statement said.

A second citation classified as "serious" was issued for failing to install a stairway railing system on one side of a stadium stage, the OSHA statement said, adding that such a violation is when "death or serious physical harm is likely to result from a hazard about which the employer knew or should have known."

A third citation considered less serious involved a failure to put weatherproof enclosures over outdoor electrical receptacles, the statement said.

In response, the SeaWorld statement said its internal review reached a different conclusion. Without providing details, the statement said the conclusions were "drawn from decades of experience caring for marine mammals."

"The safety of SeaWorld's killer whale program was already a model for marine zoological facilities around the world and the changes we are now undertaking in personal safety, facility design and communication will make the display of killer whales at SeaWorld parks safer still," the SeaWorld statement said.

It noted that killer whales at SeaWorld "are displayed under valid federal permits and under the supervision of two government agencies with directly applicable expertise: The U.S. Department of Agriculture Animal and Plant Health Inspection Service and the U.S. Department of Commerce National Marine Fisheries Service."

The SeaWorld statement also said its trainers were "among the most skilled, trained and committed zoological professionals in the world today."

"The fact that there have been so few incidents over more than 2 million separate interactions with killer whales is evidence not just of SeaWorld's commitment to safety, but to the success of that training and the skill and professionalism of our staff," the SeaWorld statement said.