BISMARCK, N.D. >> Federal and state officials announced plans Wednesday to accelerate cleanup at a camp in southern North Dakota that has housed hundreds and sometimes thousands of Dakota Access pipeline opponents.

Officials fear the camp near the Cannonball River will soon flood due to warm weather and rapid snowmelt. They worry trash and debris left behind by people who have left in recent weeks might pollute the Missouri River and other nearby waterways.

“With the amount of people that have been out there and the amount of estimated waste and trash out there, there is a good chance it will end up in the river if it is not cleaned up,” Corps spokesman Capt. Ryan Hignight said.

Local and federal officials estimate there’s enough trash and debris in the camp to fill about 2,500 pickup trucks. Garbage ranges from trash to building debris to human waste, according to Morton County Emergency Manager Tom Doering.

The camp on federal land near the pipeline route has dwindled to a few hundred people as the battle over the $3.8 billion project to move North Dakota oil to Illinois has largely moved into the courts. The Standing Rock Sioux and others believe a pipeline leak under the Missouri River would contaminate water for millions of people. Developer Energy Transfer Partners says the pipeline is safe.

The tribe has asked protesters to leave the area, and has been coordinating cleanup at the camp since late last month. Chairman Dave Archambault said at the time it was being funded from $6 million in donations the tribe received to support its pipeline fight.

Gov. Doug Burgum, State Engineer Garland Eberle and state Environmental Health Chief Dave Glatt on Tuesday issued a statement pushing for an accelerated cleanup.

“We’re really fighting the clock,” Doering said Wednesday. “There’s more garbage down there than anybody anticipated.”

Corps officials and a contractor will travel to the site later this week to assess the situation, though actual cleanup work won’t happen until the area is deemed safe for workers, Hignight said. The camp area has seen frequent and sometimes violent clashes between protesters and police.

North Dakota Gov. Doug Burgum said the state could start lining up additional contractors as early as Thursday. Who would pay the cost could be decided later, he said.

“I don’t want to sit around and argue about who’s going to pay for it while we’ve got buildings floating down the Missouri River,” he said.

Doering said local authorities are hoping for a presidential disaster declaration to open up the prospect of federal aid.

The Corps said earlier this month it will close the camp Feb. 22 — next Wednesday — to get people out of harm’s way and safeguard the environment. Burgum on Wednesday issued an evacuation order to complement the Corps deadline, though he said arresting people would be a last resort.

Hignight said the Corps was still working out details about how the shutdown would be handled. Once it’s accomplished, crews will “clean up the land to a pre-protest state,” he said.

The effort will be funded through the Corps budget, meaning taxpayers ultimately will foot the bill.