WASHINGTON — (CNN) An administrative complaint against the U.S. Environmental Protection Agency alleges negligence and demands more than $220 million in damages for its role in the Flint, Michigan, water crisis.

The discovery of high levels of lead in Flint’s tap water has unleashed a floodgate of lawsuits on behalf of aggrieved residents in the two years since officials switched the city water source from Lake Huron to the Flint River to save money.

The highly polluted river corroded old pipes and leached lead into tap water, according to experts.

Filed on the second anniversary of the water switch, Monday’s notice of class action administrative complaint was brought on behalf of hundreds of residents under the Federal Tort Claims Act.

The EPA is reviewing the complaint, agency spokesman Dan Abrams said, declining further comment.

The complaint was filed on behalf Jan Burgess and 513 other current and former Flint residents who were exposed to “toxic and highly corrosive” water for 539 days, beginning on April 25, 2014, according to the complaint.

An additional filing on behalf of another 250 Flint water users is to be made next week.

After making numerous complaints to state and city officials about poor water quality, Burgess in mid-October 2014 asked the federal EPA to investigate her concerns.

Less than a week later, EPA representative Jennifer Crooks informed Burgess that the poor water quality was “only a temporary problem” and that state and city officials were working on it, the complaint said.

Burgess did not hear again from the federal agency until April, when EPA investigators paid her a visit, the complaint said.

But the complaint cites a June 2015 memo in which EPA representative Miguel Del Toral warned that “a major concern from a public health standpoint is the absence of corrosion control treatment in the City of Flint for mitigating lead and copper levels in the drinking water.”

In an email that month, Del Toral said failing to tell residents of the contaminated water “borders on criminal neglect.”

Michael Pitt, an attorney for the plaintiffs, said in a statement, “The EPA heard the alarm bell loud and clear but chose to ignore the profound environmental and public health issues brought to its attention in the early stages of this disaster.

“This agency attitude of ‘public be damned’ amounts to a cruel and unspeakable act of environmental injustice for which damages will have to be paid to the thousands of injured water users.”

EPA Administrator Gina McCarthy appeared before a congressional panel looking into the water crisis in March.

Despite emails and internal memos that show the EPA staffers were aware of the high levels of lead as early as February 2015 and were communicating regularly with state officials, McCarthy claimed Michigan officials hindered the EPA’s ability to oversee and stop the crisis.

An emergency wasn’t declared by the EPA until January. Susan Hedman, the EPA regional director, resigned in February over her handling of the crisis.

McCarthy said, “I will take responsibility for not pushing hard enough, but I will not take responsibility for causing this problem. It was not EPA at the helm when this happened.”

More than a dozen lawsuits, including several class-action ones, have been filed in state, county and federal courts in Michigan, according to legal experts.

The remedies sought range from monetary compensation for lead poisoning to refunds for water bills.

Most cases focus on the youngest victims of the man-made environmental calamity: the scores of children whose lead exposure could lead to maladies ranging from neurological disorders, such as seizures, to language and learning disabilities.