Update 7/25: 

While the Washington Monument is still slated to reopen to visitors in August, it won’t do so until later in the month, according to the National Park Service.

Crews continue to work on completing repairs and security updates to the monument, says Mike Litterst, a spokesperson for NPS. He did not provide a specific date for the opening.

“It’s not likely to be in the next couple of weeks,” Litterst says. “When everything is done, we’ll open.”

Original:

Hoping to take family and friends to the top of the Washington Monument this summer? Tell them to push off their visit until the end of the season.

The National Park Service announced Monday that the National Mall landmark will not reopen to visitors until August. The monument has been closed since August 2016 to construct a new visitor screening facility and modernize the elevator. It was originally scheduled to reopen this spring.

According to the Park Service, completion of the new security building has been delayed after “possibly contaminated soil” was found in the construction area. The Park Service believes the soil was introduced in the 1880s when the monument was being completed. It poses no public health risk. The Park Service did not immediately respond to a request for comment on the details of the contaminating materials and how and why they will be mitigated.

When the new screening center is complete, it will replace a temporary structure constructed after the terrorist attacks on Sept 11, 2001. The new glass-and-steel facility was paid for by the Park Service’s annual budget.

The monument’s new elevator will take visitors 500 feet up to the observation area. The project is “substantially complete,” pending final testing and safety systems certification. The old elevator system had chronic issues, leading to service interruptions and visitor evacuations down the monument’s 897 steps.

The elevator renovations were funded by David Rubenstein, a philanthropist and the co-founder of the private equity firm the Carlyle Group. He is a frequent backer of federally-managed parks and sites in the District that are of national interest. He funded restoration work on the Lincoln Memorial and the U.S. Marine Corps Memorial, and he supports the panda habitat and associated research at the Smithsonian National Zoo.

He also donated $7.5 million to repair the monument after a rare earthquake in 2011 cracked the marble and granite structure. It was encased in scaffolding during much of the five ensuing years of repairs.

This story originally appeared on WAMU.