Soil at a public golf course in Washington where the Trump administration dumped debris from the demolition of the White House East Wing has tested positive for lead, chromium and other toxic metals, according to data released by the National Park Service.

The data, which the Park Service published on its website last week, showed relatively low levels of these contaminants in the soil at East Potomac Golf Links.

Yet the dump raised questions about the decision by the Trump administration to bypass environmental laws when it dropped truckloads of mud, rebar, plaster and other debris in the middle of the popular public course near the Jefferson Memorial.

The president is planning a sweeping overhaul of the 105-year-old golf course, where generations have played in view of monuments and memorials at bargain rates that currently run $42 for 18 holes on weekdays. Mr. Trump wants to transform it into a championship course, which would likely spell the end to an existing mini-golf course as well as a surrounding roadway that is popular with cyclists and runners.

The soil test results have provided ammunition for the preservationist group that is suing over the dumping of debris and that is also fighting the broader takeover of the golf course. In its lawsuit, the nonprofit DC Preservation League argued that the dumping was unlawful and possibly hazardous to golfers, community members and wildlife.

“We knew that the demolition of the East Wing and the changes to East Potomac were legally toxic; now we know they’re environmentally toxic as well,” said Norm Eisen, the executive chair of Democracy Defenders Fund. It is representing the DC Preservation League and two area residents in the case, as are Democracy Forward and Lowell & Associates.