Tribal leaders in South Dakota plan to protest President Trump’s appearance Friday at an elaborate Mount Rushmore fireworks display, arguing that the event could worsen the state’s coronavirus outbreak and violates Native Americans’ claims to the Black Hills.

The objections of seven Sioux tribal governments — all of which had raised concerns as Trump officials were planning the trip — underscore how the president has become a polarizing figure regardless of where he travels in the United States. Critics of the president demonstrated outside of his recent rallies in Tulsa and Phoenix, and they will greet him once he returns to Washington on Saturday for a “Salute to America” celebration he has orchestrated to commemorate Independence Day.

National Park Service officials have not allowed pyrotechnics at Mount Rushmore for more than a decade, out of concern that they could set off wildfires and contaminate drinking water supplies. The memorial is surrounded by 1,200 acres of forested lands and lies next to the Black Hills National Forest’s Black Elk Wilderness. Just last week, a wildfire erupted six miles south of the memorial, destroying about 60 acres before it was extinguished with help from 117 firefighters and eight aircraft.

Trump has pushed to resume fireworks at the memorial to four U.S. presidents, and this spring the Interior Department finalized an environmental assessment that concluded that they would not pose a significant risk to the land or water supplies.

But that same analysis indicated that half a dozen tribes had “expressed an overall objection to the event and its impacts.” Based on past pyrotechnic shows, the assessment concluded, resuming fireworks “would result in additional unexploded ordnance and debris on the landscape.”

In a meeting in late February, tribal representatives called the Black Hills landscape “inexplicably sacred,” according to the document.

“We are looking forward to a safe and successful event and hope everyone enjoys the extraordinary firework display after more than a decade hiatus at Mount Rushmore,” said Interior Department spokesman Nicholas Goodwin."

The U.S. government acknowledged the Great Sioux nation’s jurisdiction over the Black Hills in two separate treaties, in 1851 and 1868. Federal officials took over part of the area after gold was discovered there, but a 1980 Supreme Court decision rejected the Sioux’s claim that the land had been stolen from them.

Jeffrey Ostler, a professor at the University of Oregon who specializes in the tribe’s history, said the Black Hills, and Mount Rushmore in particular, play a central role in the tribe’s spiritual beliefs. The mountain in which the monument is carved is called “Paha Sapa,” or the Six Grandfathers in the Sioux language, after the earth, sky and four directions.

For this reason, Julian Bear Runner, president of the Oglala Sioux tribe, said Trump’s event amounted to an act of arrogance and desecration.

“It’s like if he tried to go and have a fireworks display celebrating independence at the Vatican,” he said.

A Fourth of July event at the site is pouring salt in a wound, said Ricky Gray Grass, a member of the Oglala Sioux’s executive council. “The whole Black Hills is sacred. For them to come and carve the presidents, slave owners who have no meaning to us, it was an insult," he said.

Gray Grass said Sioux leaders met with federal and state officials as far back as February, including Rene Ohms, resource program manager at Mount Rushmore National Memorial. “They kind of just came in and listened. At the end, they kind of just blew us off … saying, ‘We’re still going to have this fireworks display,’ ”

Angered by what they considered a snub and motivated by the Black Lives Matter protests, young members of the tribe organized a protest, which the executive council backed. “They took our minerals, took our gold, took our water and have taken our forestry,” Gray Grass said. “It’s time our young people took that stance.”

On Twitter earlier this week, the Democratic National Committee seized on the spiritual importance of the Black Hills, writing that the rally would be “glorifying white supremacy at Mount Rushmore — a region once sacred to tribal communities."

A DNC spokesperson did not respond to a request for comment on the tweet, which drew heavy backlash on conservative media sites and has since been deleted.

Ostler, the Oregon historian, said that in a moment when many Americans are beginning to understand deeper truths about the country’s history, Mount Rushmore might come under question, too.

The state historian who initially commissioned the sculpture wanted to depict key figures in the American West, including Sacagawea, the Lemhi Shoshone woman who helped guide the Lewis and Clark Expedition. But sculptor Gutzon Borglum successfully argued that it would have greater appeal if it featured U.S. presidents — including Abraham Lincoln, who ordered the hanging of 38 Sioux in the Dakota war of 1862. Work on the memorial began in 1927 and was completed in 1941.

“It is indeed a monument that assumes white supremacy,” Ostler said, “and that is celebrating an America that conquered Lakota people, took their land and put up a monument there without any thought to their views of it.”

Meanwhile, in Washington, three Democrats on the Senate Appropriations Committee asked the Government Accountability Office to investigate the costs and details of the president’s “Salute to America” events. Calling them “de facto political events with official funds,” Sens. Tom Udall (N.M.), Patrick J. Leahy (Vt.) and Chris Van Hollen (Md.) requested to know the estimated costs to each federal department involved: Interior, Defense, Homeland Security, and Health and Human Services.

“Did all agency expenditures comply with the principles of Federal appropriations law?” the senators asked in the June 25 request. Concerned that the events could lead to large crowds and an increased spread of the coronavirus, they asked: “Did the Trump administration and its event partners take the necessary steps to ensure that any public Fourth of July events fully conformed to public health recommendations from the Centers for Disease Control and Prevention?”

The National Park Service’s assessment concluded that after consulting with several tribes, as well as experts and the public, “it is the superintendent’s professional judgment that there will be no impairment of park resources and values.”

Earlier drafts of the environmental assessment included a section on the event’s impact on human health and safety, according to documents released under the Freedom of Information Act, which was not included in the final analysis. An earlier draft also suggested limiting attendance to 2,000, as opposed to the 7,500 who will be allowed under the current plan.

The state will not require attendees to wear masks or engage in social distancing, although Goodwin said that park staff members will be encouraging such measures. “A supply of cloth face coverings will be available and distributed on-site,” he said.

State officials are monitoring weather to determine if it’s safe to ignite fireworks on Friday: At the moment, the state projects a moderate fire danger. Temperatures are expected to be in the low 90s, and there is a chance of thunderstorms that could be accompanied by high winds.

Joe Lowe, who served as fire chief for South Dakota’s Division of Wildland Fire from 2001 to 2012, said in a phone interview that the embers from pyrotechnics can quickly ignite dry pine needles on the memorial site, which is why his team always pre-positioned firefighting teams to extinguish them.

“So setting off fireworks in potentially dry fuels, in steep slopes, with high temperatures and possible downdraft winds from a thunderstorm, may pose a fire risk,” Lowe said. The temperature forecast for Friday is higher than 90 degrees.

At the memorial, practice runs for Friday’s aerial show have been underway. The show includes the Blue Angels piloting F/A-18s, as well as military personnel flying Black Hawk helicopters and B-1 bombers.

Asked how much the federal government is spending on the event, Goodwin did not say.

Some park advocates warn that congregating on public land could pose a danger in light of the coronavirus pandemic.

“Given how contagious covid-19 is, we have been cautioning people about the crowded conditions in many national parks which might make social distancing extremely difficult,” Kristen Brengel, senior vice president of government affairs at the National Parks Conservation Association, said in an email. “The July Fourth holiday and planned celebrations in some national parks will attract visitors from around the country making these events more risky.”

Correction: An earlier version of this story incorrectly described the type of aircraft used by the Blue Angels.