Parent company Southern Co. entered a filing May 5 that said the examination appears to be looking mainly at periods after 2010, as well as “accounting matters, disclosure controls and procedures, and internal controls over financial reporting” as it relates to the facility.

Southern officials did not indicate how far along the probe may be or when it commenced.

Kemper now has a price tag of $6.7 billion; however, at the start of planning, its backers had it approved at a cost of $2.9 billion. In the time since, delays and cost overruns have steadily sent the total rising.

“The company started to pick up indications that public awareness of the investigation had matured to a point that, in our judgment, it should be disclosed,” Mississippi Power spokesman Jeff Shepard said last week, adding that no further details could be provided because of the ongoing investigation.

“While we cannot predict the ultimate outcome, as we have said in our disclosures on this matter, we do not expect the investigation to have a material impact on the financial statements of either Southern Co. or Mississippi Power.”

Kemper stands to be the country’s first large-scale coal gasification plant that also utilizes carbon capture. It is currently running with natural gas, but CEO Tom Fanning told Bloomberg recently that it should be switching over to lignite coal by summer.

At the same time, the company said it had added another $61 million to the project’s costs due to expense charges for equipment repairs and other issues tied to the delays.