The Harriet Tubman Historical Marker at Brodess Farm in Cambridge, Md. The farm, historically recognized as the abolitionist’s birthplace, is near the new national monument. (Linda Davidson/THE WASHINGTON POST)

President Obama on Monday will designate a new national monument on Maryland’s Eastern Shore commemorating famed abolitionist Harriet Tubman and the Underground Railroad, a White House official said.

The Tubman memorial will be among five new national monuments that Obama is expected to add to the nation’s list of protected land. In a rare invocation of his executive powers, Obama also will designate the First State National Monument in Delaware, which will make Delaware the last of the 50 states to have a national park.

The three other sites Obama will designate are the Rio Grande del Norte National Monument in New Mexico, the Charles Young Buffalo Soldiers National Monument in Ohio and the San Juan Islands National Monument in Washington state.

The Harriet Tubman Underground Railroad National Monument in Dorchester County, honoring the native Marylander who escaped slavery and then helped guide other slaves to freedom, will be the first national monument commemorating an African American woman.

Donald Pinder, president of a small group in Dorchester that runs the Harriet Tubman Museum and Educational Center and has been advocating for the national designation, said he was “very grateful” to Obama.

“Here’s Harriet Tubman, someone that was born into slavery, actually had to run from the South to North to escape her bondage and then helped others,” Pinder said. “This particular woman had several other choices, and the first choice would have been to start a new life and to live as a free citizen of the United States, but she chose to work on the Underground Railroad to save others.”

Obama is using the authority he is accorded by the Antiquities Act, which presidents have exercised for more than a century to protect natural and historic sites such as the Grand Canyon and the Statue of Liberty.

But not everyone applauds the idea.

Rep. Rob Bishop (R-Utah), chairman of the public lands and environmental regulation subcommittee, accused Obama of designating federal lands by “executive fiat.”

“The use of the Antiquities Act cuts out public participation,” Bishop said in a statement. “There is a right way to designate federal lands, and there is a wrong way. Executive fiat is unquestionably the wrong way and is an abuse of executive privilege. The fact that Congress doesn’t capitulate to the President’s political whims on his specific timeline is hardly justification for taking unilateral action.”

But proponents noted that each of the five sites had strong support from local officials as well as conservation groups. They suggested that Obama was designating the sites by executive authority because the last Congress has failed to pass legislation creating new national parks.

The White House had no official comment Friday because Obama does not plan to formally announce them until Monday. A White House official, who spoke on the condition of anonymity, noted that Department of the Interior lands support $363 billion in economic activity annually and 2.2 million jobs across the country.

During his first term, Obama designated four monuments: the Cesar E. Chavez National Monument at the United Farm Workers of America headquarters in California; the Fort Monroe National Monument at a former Civil War-era Army post in Virginia; the Fort Ord National Monument at a former military base in California; and Chimney Rock National Monument in Colorado’s San Juan National Forest.

But Obama has come under criticism for not protecting more lands. Bruce Babbitt, interior secretary in the Clinton administration, called on Obama in a recent speech to focus as much attention on land conservation as he does on oil and gas development.

Among the national monuments Obama will designate on Monday is the Rio Grande del Norte, a 240,000-acre space that will protect a wildlife habitat now prized by hunters, as well as create rafting and camping areas. The New Mexico site will also highlight the Southwest’s Hispanic and Native American tribal heritage.

The San Juan Islands National Monument includes about 1,000 acres off Washington’s northwest coast.

In Xenia, Ohio, Obama will commemorate the Charles Young Buffalo Soldiers National Monument on the site of the family home of Col. Charles Young, an Army officer who was only the third African American to graduate from West Point and the first to achieve the rank of colonel.

The First State National Monument will include several historic properties as well as about 1,000 acres of the Brandywine Valley, along Delaware’s border with Pennsylvania. The park will honor the state’s early settlement by Dutch, English and Swedish immigrants.

With Monday’s declaration, the National Park Service will be whole, as Delaware becomes the 50th state to have a national monument. This has been a longtime priority for Vice President Biden, a former senator from Delaware.

“This national monument will tell the story of the essential role my state played in the history of the United States,” Biden said in a statement. “I couldn’t be more proud to call Delaware home.”

Sen. Tom Carper (D-Del.) lamented that until now Delaware was the only states in the nation not to have a national park.

“On Monday, not only will the national park system gain an important story about the crucial role the First State played in the founding of our country — a story that will now be preserved for generations to come — but our state will now welcome the many economic opportunities that surround a new national monument and can help boost local businesses and create jobs,” Carper said in a statement.

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