DETROIT — Michigan’s top environmental officer was by turns cooperative and confrontational with the U.S. Environmental Protection Agency in a letter pledging to work with the federal government to ensure the safety of Flint’s drinking water but challenging the legality of some federal demands.

Michigan Department of Environmental Quality Director Keith Creagh wrote Friday in a letter to EPA Administrator Gina McCarthy that the state “is committed to working” with her department and Flint to deal with the city’s lead-contamination problem.

But he said the state has “legal and factual concerns” with an EPA order a day earlier taking state and city officials to task for their efforts so far and requiring them to take specific actions.

Creagh said Michigan “has complied with every recent demand” of the EPA and that Thursday’s federal order “does not reference the tens of millions of dollars expended by ... the state for water filters, drinking water, testing and medical services.”

“The order demands that the state take certain actions, but fails to note that many of those actions ... have already been taken,” Creagh wrote.

Flint’s water became contaminated with lead when the city switched from the Detroit municipal system and began drawing from the Flint River in April 2014 to save the financially struggling city money. The water was not properly treated to keep lead from pipes from leaching into the supply.

Some children’s blood has tested positive for lead, a potent neurotoxin linked to learning disabilities, lower IQ and behavioral problems.

Creagh wrote that state officials don’t know whether it’s legal for the EPA to order Michigan to take such actions.

Among other requirements, the EPA said the city should: submit plans for ensuring Flint’s water has adequate treatment, including corrosion controls; ensure city personnel are qualified to operate the water system in a way that meets federal quality standards; and create a website where the public can get information.

Earlier Friday, The Flint Water Advisory Task Force issued recommendations to Snyder aimed at restoring reliable drinking water in Flint. The advisory group said its recommendations are more detailed and comprehensive than what the EPA ordered, and Snyder said officials would “move as quickly as possible to determine the best way to achieve the results.”

Separately, Snyder announced the suspensions of two employees of the state Department of Environmental Quality in connection with regulatory failures that led to the crisis.

The panel’s recommendations included working with the EPA staff on a comprehensive lead-sampling program and seeking help from the federal Centers for Disease Control and Prevention in assessing an outbreak of Legionnaires’ disease and its cause.