DANVILLE — Steadily increasing levels of boron, manganese and sulfate were found in the ground water around Vermilion Power Station in 2011, according to state test results.
The Illinois Environmental Protection Agency filed a violation notice against Vermilion Power Station owner, Dynegy Midwest Generation, in July 2012 notifying the company of the excessive chemical levels as a result of coal ash ponds on the property and citing concerns the chemicals could reach nearby bodies of water.
The Dynegy site is located north of Oakwood.
According to figures filed with that IEPA notice, four groundwater wells were tested between March and October 2011. In each well, sample results were above the standard chemical limits set by state statute and, in several tests, were double or almost triple the standard.
IEPA spokesman Andrew Mason said state officials and Dynegy have moved through the statutory process up to this point, with both sides working to agree to a compliance commitment agreement intended to address the problems caused by the violations.
Currently, Dynegy is conducting engineering and technical research — including hydrogeological studies — to determine what kind of impact the chemical levels would have on the nearby Middle Fork River. The plant is upstream from Kickapoo State Park.
The studies are “needed to determine how best to close out the ash ponds that are causing the groundwater problems,” Mason said in an email.
The IEPA expects to receive the latest version of Dynegy’s research by the fall. Mason said officials will determine if it adequately addresses the environmental concerns and, if it doesn’t, return to the company for changes.
Once a plan is settled upon, Dynegy will be required to fulfill the terms of the agreement.
According to 2011 testing results filed by the IEPA, levels of boron at three testing wells on site far exceeded the groundwater standard of 2 milligrams per liter. At one testing well, the boron levels measured at 29 mg/l in May 2011 and increased to 40 mg/l liter by October 2011.
Manganese levels tested high at another well, coming in at 1 mg/l compared to the .15 mg/l dictated by state statute. Sulfate levels had the biggest jump during the five-month period, going from 1,000 mg/l to 1,500 mg/l. State statutes call for groundwater levels no higher than 400 mg/l.
The chemicals could have a trickle-down effect if they seep into surface water, beginning with aquatic life, according to Mason.“You could start to see elevated concentrations in fish tissue, which would raise concerns about how much and how often humans would be advised to consume fish from that body of water,” he said in an email.
“Excess consumption of these materials could have harmful effects.”
Dynegy announced plans in December 2010 to “mothball” the coal-burning Vermilion Power Generation Facility near Oakwood by the end of the first quarter of 2011. The facility — made up of two turbine units — celebrated its 50th anniversary in 2006.
The 176-megawatt per hour coal-burning facility operates 24 hours a day, seven days a week and produces enough electricity to supply 40,000-50,000 customers. One of the turbines generates 77 megawatts of power an hour, while the other produces 105 megawatts an hour.