The Securities and Exchange Commission has served a subpoena to Peabody Energy over the new $4 billion Prairie State Energy Campus.

The subpoena was mentioned in Peabody Energy's annual 10-K report filed with the SEC.

The report cites that St. Louis-based Peabody was issued the subpoena in January and the company is cooperating with the investigation and believes the issues will be resolved "without adverse effect on its financial condition."

The report does not disclose further details.

"I can tell you that we have received an inquiry from the SEC regarding the development of the Prairie State Energy Campus, and we are cooperating with any questions they may have regarding it," Meg Gallagher, spokeswoman for Peabody Energy said in statement released Tuesday. "We look forward to sharing information on what is a highly successful project."

Peabody Energy is the world's largest private-sector coal company's.

Peabody Energy announced plans in 2007 to build the 1,600-megawatt, coal-fired electrical power plant in Washington County. The company sold about 95 percent of its stake in the plant to eight power entities that represent 217 municipalities and 17 electric membership cooperatives in Illinois, Indiana, Kentucky, Michigan, Missouri, Ohio, Virginia and West Virginia.

One of the stakeholders is the Illinois Municipal Electric Agency in Springfield, which owns a 15 percent share.

Agency spokesman Phillip "Doc" Mueller said the organization was contacted by the SEC several weeks ago. Mueller said the SEC has requested information, but he does not know what the investigation is about.

"There is no indication that we're involved in it in any way," Mueller said. "We're responding to the SEC's inquiry. We really don't know anything else about it."

Contact reporter Will Buss at wbuss@bnd.com or 239-2526.