(NewsNation) — Arizona Gov. Doug Ducey continues to direct contractors to fill holes along the U.S.-Mexico border by stacking shipping containers, but not without opposition.

Supporters say a finished wall is necessary to streamline border crossings and make Border Patrol more effective, but critics say it’s dangerous for people and the environment.

Those opposed to the governor’s shipping container plan say it threatens to harm the environment, presents a public safety risk, and violates federal law. The plan is running into a number of hurdles.

Ducey says he’s not backing down from his plan despite the list of concerns.

Safety concerns

From heavy machinery to bomb threats, the construction of a shipping-container barrier has raised safety concerns among police and forest officials.

Recently, a group of about 20 protesters showed their disdain for the governor’s project by holding signs reading, “Stop trashing our public land” and “Governor Ducey’s 100 million dollar junkyard.”

Additionally, a representative from the National Forest Service told Arizona-based KTAR News the project is a “safety concern” and urged visitors to stay away from the makeshift border wall.

The National Forest Service has also issued a warning advising people to avoid the area, where construction equipment and unauthorized armed security personnel are on site.

Independent of those concerns, a group in late October allegedly threatened to blow up the shipping containers along the border near Yuma, Arizona, NewsNation’s Ali Bradley reported at the time.

Federal land

It was about four months ago that Ducey ordered the closure of a 1,000-foot gap in the border wall — an order that affected, without explicit permission, on federal land, 

Federal government agencies have said the containers are unlawful and have pushed for the dismissal of Ducey’s lawsuit, which seeks to have the land designated for state use.

The federal government also has called for the containers’ removal, citing pre-existing plans and contracts to fill the holes along the border wall in the coming months.

In any case, Ducey’s office said it has no intention of halting the project as it moves forward.

Santa Cruz County Sheriff David Hathaway, however, said anyone who tries to place shipping containers along the border in his jurisdiction will be arrested on illegal dumping charges, according to a Dec. 2 report from Nogales International.

Wildlife migration

The Center for Biological Diversity said that in addition to violating federal law, harming endangered wildlife and blighting the landscape, the shipping containers will block hundreds of ephemeral streams and washes.

In October, the center filed a notice of intent to sue Ducey’s administration if the shipping containers in Cochise County are not removed, and it has since asked to join the Biden administration as a defendant in the governor’s lawsuit challenging federal authority along the border.

The notice said the containers would obstruct a critical migration path for jaguars and ocelots and prevent their recovery in the United States, violating the Endangered Species Act.

The Bureau of Reclamation has additionally raised concerns that the containers are on federal and Cocopah Indian tribal land and therefore violate federal law.

The construction of the border wall before the shipping containers had already done damage, according to some wildlife activists.

A portion of the wall — construction of which began during President Donald Trump’s administration — cuts through Organ Pipe Natural Cactus Park in Southern Arizona.

Construction of the wall risks both destroying cacti that can live to be 200 years old and cutting off animals from essential water sources, activists have said.

What’s next?

As the project moves ahead, Ducey’s office says it has no intention of halting it. Earlier this month, Cochise County Sheriff Mark Dannels told NewsNation he hopes it sends a message to the Biden administration.

“We feel like we are being forgotten down here; enough is enough,” Dannels said. “Work with us, we are willing to work with you as national sheriffs, state sheriffs, western sheriffs; let’s work together for the good of the people.”

The Biden administration is considering plans to deal with the ongoing immigration situation across all border states, as the pandemic-era immigration restrictions under the policy known as Title 42 come to an end on Dec. 21.

In Arizona, Ducey said the shipping container wall will cost $95 million and will span 10 miles, utilizing roughly 3,000 shipping containers when it is completed. Incoming Gov.-elect Katie Hobbs has called the container wall a political stunt. She has not said, however, if she’ll have them removed when she takes office.