A drilling rig became unstable last Wednesday as Ranchers Exploration Partners was drilling an oil well atop the long-shuttered Johnston Landfill in Windsor, a site near the River West and Ridge West subdivisions south of Colorado Highway 392.

The well site is on a hill above a gulch that drains into a nearby reservoir along the Poudre River.

After Greeley-based Ranchers Exploration attempted to stabilize the drilling rig with cement, landfill debris and other trash were seen being expelled from the well bore, and the rig lost "circulation of fluids, likely due to the presence of highly permeable unconsolidated landfill materials," according to a cease-and-desist order the state served Ranchers last week.

In last week's cease and desist order, Colorado Oil and Gas Conservation Commission Acting Director Thomas Kerr declared an emergency because Ranchers' operation poses an environment and public health risk.

"They need to move off of that landfill that is under their pad and drill there, or find a different loca-tion," Kerr said Tuesday. "If they're on the (approved drilling) location and they're not over the landfill, they should be fine to drill, but physically drilling through refuse is not acceptable."

The incident occurred despite that Ranchers moved the well location last year to a site where both state and Larimer County officials thought would be safe to drill.

Previously, the state had required Ranchers to stop excavating the landfill cap at its original drilling site, cease spreading solid waste around the site and arrange for the waste to be removed.

A state inspection after last week's incident showed that Ranchers had not built any secondary con-tainment for sewage, chemicals or stormwater runoff that might flow from the well site.

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