Ameren Missouri is still investigating what caused elevated radioactive chemical levels in water in a monitoring well at its Callaway Energy Center in late July, but officials assured it has not affected the drinking water and insisted the only contamination is on the nuclear plant's property.
When the Fulton Sun asked if Ameren has tested off-site water since discovering contaminated on the plant's property in rural Reform southeast of Fulton, a spokesman on behalf of Senior Director of Nuclear Operations Barry Cox said the plant takes samples quarterly at various wells on and off plant property.
The most recent sample off-plant property was taken May 28 and it did not show elevated chemical levels. The next quarterly sample of a well off plant property is scheduled for later this month.
Ameren found radioactive tritium and Cobalt-60, both byproducts of a nuclear reaction, in a water well near the nuclear plant's cooling towers on plant property when recently checking equipment and systems at the plant - a routine procedure.
Victor Dricks with the Nuclear Regulatory Commission said the chemical concentrations in the water exceed EPA drinking water limits. The NRC is the government-run organization that oversees the privately-owned nuclear power plants like Ameren's Callaway Energy Center.
Multiple nuclear plants around the country have also found tritium leaks on plant property and Dricks said the industry launched an aggressive monitoring system.
"The industry has undertaken a monitoring program to search for any indication of unplanned releases of tritium and as part of that program they have dug sampling wells both on the plant property and off the plant property so they can detect any releases," Dricks said. "These releases were found on the plant's property. They don't pose danger to people living near the plant or to the workers at the plant."
Ed Smith with Missouri Coalition for the Environment (MCE) said he hasn't seen enough information to be convinced that the radioactivity is contained on Ameren Missouri property.
"Unless Ameren can establish and show that they have tested the groundwater off site, I don't think that Ameren can say that (it is contained) either. I'm not doubting their claim, I just would like to know what they are basing that on," Smith said.
The Fulton Sun asked Missouri Department of Natural Resources what role the DNR has when it comes to nuclear power plants. DNR Communications Director Gena Terlizzi said the Callaway plant is under the authority of the NRC, not the DNR. The NRC as the federal safety regulator has resident safety inspectors who work at the plant each day. Dricks said the inspectors are monitoring the plant's response to the event. The inspectors will conduct their own review of the response and situation, which the NRC will publish any findings in its quarterly inspection report.
Lara Uselding with the NRC said that report should be out by November if the inspector has any finds to report.
The NRC event report of the recent leak stated that the plant tested another sample on Aug. 1. Cox said that was from the same on-site monitoring well in which the elevated radioactive chemicals were found. The plant took the sample to verify its first results.
The monitoring well with contaminated water is on plant property and next to a manhole where the plant's discharging piping meets with the cooling tower blowdown piping, according to the NRC event notification report. The Callaway Energy Center suspended the releases from the plant discharge line to stop the flow of water from those pipes. It is still investigating the source of the chemical leak that caused the water to be contaminated. The plant remained at full power.
Ameren Missouri Spokesman Bryan Daniels said the leak is contained to Ameren Missouri property.
"We are still investigating the cause of it and the scale of the issue," Daniels said. "It is Ameren Missouri property. This issue doesn't impact any area outside of Ameren Missouri property."
The Fulton Sun also asked Terlizzi with the DNR if it is possible for contaminated water on plant property to affect ground water off-plant property. She did not return emails answering those questions before press time.
Ameren Missouri released a statement that, in part, stated, "Callaway's redundant mechanisms for human and environmental safety operated as designed by detecting an issue, which is isolated on Ameren Missouri property. There is no threat to drinking water in the area. Safety is our top priority and the issue poses no impact on the health or safety of the public or Ameren Missouri employees."
Smith said MCE sent some questions and concerns to the NRC. The NRC responded to those questions last week. MCE asked the NRC if it knew how long the radioactive chemicals were being released into the groundwater in the monitoring well at the plant. Uselding responded that the NRC did not yet know how long the leak occurred. She also noted that all other groundwater monitoring wells - that are tested quarterly - did not show signs of contamination. MCE also asked if "in-stream monitoring has been conducted on local surface waters to determine if contaminated groundwater is connected to surface water flows." Uselding said in-stream monitoring has been conducted.
The Callaway Energy Center reported the high chemical levels to the NRC. Daniels said Ameren Missouri has been transparent in immediately reporting the leak to the NRC and to DNR.
Smith said Ameren is not required to report the leak and did so voluntarily.