A group of neighbors in Carlton have sued Missoula County over a gravel pit expansion inside a residentially zoned neighborhood, alleging that commissioners disregarded zoning and the public right to know for decades. 

The lawsuit, filed in Missoula County District Court this month, comes after county commissioners granted a gravel pit expansion to allow Western Materials to mine up to 150 acres of gravel in the north edge of the Bitterroot Valley.

The gravel pit has existed for decades within an old zoning district that overlays the Carlton neighborhood.

That same district does not allow for gravel pit operations, but a landowner in the neighborhood slowly expanded a mining operation for decades, including securing a non-conforming use title from the county in the early 2000s. 

The commissioners said in August that they approved the gravel pit because the site has been in operation for decades and that gravel was an essential material for construction projects across the Missoula Valley.

The approval also required mitigations like a wildlife corridor to ease the impact of the mine onto neighboring residents. 

Graham Coppes, who is representing the Carlton Neighborhood Trust, wrote that commissioners should have never approved the pit in the first place, and the updated decision should be blocked by a court. 

"The Hendricksen Pit has continuously expanded through the years as a result of negligent fact-finding, due process, and public participation opportunities by the County to verify the history of the pit and confirm that it was or was not a lawful nonconforming use that existed at the time of zoning in 1976," the lawsuit read. 

The lawsuit is 40 pages with more than 180 pages of supplemental information. The suit is asking for a halt to the pit because of a violation of zoning rules and the public's right to know clause from the state constitution. 

The county commissioners debated back and forth whether the pit should be allowed during five meetings stretching back into 2023. In April, Commissioner Josh Slotnick said he struggled to make a decision after evidence showed the pit shouldn't have been created under the area's zoning. 

"It appears after all this listening that the permits for the pit from the DEQ were built on a lie," Slotnick said at the time. "And now, a variance is asked for a different chunk of land, proposed by a different person that had nothing to do with this pit ... there's no law breaking by applying for a zoning variance. Is that what is happening here, or are we extending a lie?"

Missoula County Communications Manager Allison Franz told the Missoulian that the county does not comment on active litigation. 

The case is currently presided by District Court Judge Dusty Deschamps. A hearing for the case had not been set as of Monday.