GILLETTE (AP) - A coal-bed methane company is suing a coal company, saying an expansion of the Cordero Rojo coal mine was illegal and caused the contamination of several nearby gas wells.

Sheridan-based WYTEX Ventures filed suit against Cordero Mining Co., a subsidiary of Rio Tinto Energy America, April 25 in Campbell County District Court. WYTEX is seeking about $140,000 for alleged lost production and unsalvageable equipment.

WYTEX officials declined to comment. Rio Tinto Energy America received the complaint Tuesday, according to Bob Green, the company's director of sustainable development.

"We disagree with the allegations made in the complaint and are deeply concerned by the actions taken by WYTEX," Green said in a prepared statement. "We are reviewing this complaint and will respond appropriately and in accordance with proper process and procedures."

The lawsuit claims that Cordero drilled 200 de-watering and monitoring wells as part of its mining operations. The wells allegedly contaminated WYTEX's coal-bed methane wells with oxygen and impurities and made the wells commercially nonviable.

WYTEX wants $116,172 to make up for production losses it blames on Cordero. The company also wants to be paid $23,672 for equipment it says was lost because of a premature land takeover.

WYTEX claims that on June 27, Cordero gave WYTEX workers 30 minutes to shut down and abandon four wells contrary to prior agreements between the companies.

A surface use agreement signed before WYTEX took over the wells from another company said the company's rights were subordinate to the right of Cordero to continue to mine the leased lands for coal. But the agreement contained several requirements before it could push WYTEX aside, including giving 120 days' notice for WYTEX to move its roads, gas pipelines and compressors, the lawsuit alleges.

WYTEX also claims that Cordero was supposed to provide 60 days' notice before any mining operations that would require it to occupy land being developed by WYTEX. In addition, Cordero allegedly was supposed to pay the costs of plugging and abandoning wells if the company expanded faster than a mine plan developed in 2001.

The lawsuit said a Cordero representative recognized the mistake and told WYTEX to bill Cordero for the move. WYTEX sent Cordero a $1,405 invoice July 19, but the lawsuit said that money was never paid.