Cliffside Steam Station

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Cliffside Steam Station has 9 groundwater monitoring wells, 3 of which have been polluted above federal advisory levels based on samples collected between April 01, 2011 and December 01, 2014. Groundwater at this site contains unsafe levels of manganese.

Site description

Duke Energy's Cliffside Steam Station began operating in 1940 in Cleveland and Rutherford Counties, North Carolina, and at its peak, it could generate up to 1,387 megawatts (MW) of electricity. In October 2011, four of the coal-fired units were retired. The fifth unit, which began operating in 1972, is located about a half mile away from the other four units has been upgraded in recent years. The newest unit, clean coal unit 6, came online in 2012 and can generate up to 825 MW of electricity.

The site is home to one active ash basin and two retired ash basins. In 2009, the active ash basin had a surface area of 84 acres, could contain 5,025 acre-feet of waste, and was approximately 80% full. One of the retired basins had a surface area of 46 acres and has been capped with soil, while the other is a full un-capped pond with a surface area of 14 acres. In October 2005, floodwaters from a nearby creek entered the 14-acre retired ash basin, causing the impoundment to overflow and one of the dikes to fail.

In August 2013, the State of North Carolina entered into a consent decree with Duke Energy regarding seeps and other un-permitted discharges to groundwater from the site. In March 2014, the North Carolina Department of the Environment and Natural Resources (NCDENR) cited Duke Energy for stormwater and dam safety violations related to all three of its on-site ash ponds. The NCDENR also found thallium in surface waters near the base of one of the ash ponds.

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Monitoring Wells Wells reporting one or more exceedances for at least one pollutant.
3 / 9
Wells not shown Locations for the following wells are unavailable:

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No exceedances
One or more exeedances
No data available
Other designation
Well "halo" size corresponds to mean concentration. Please note that some wells may not be visible on the map due to overlapping locations.
Pollutants monitored and above guidelines
Tip: Click on a contaminant to view wells that have recorded exceedances. Click again to remove the filter. manganese
Pollutants monitored and below guidelines
antimony arsenic barium boron cadmium chromium copper lead mercury nickel nitrate selenium sulfate thallium
Pollutants not monitored
ammonia, beryllium, cobalt, cyanide, fluoride, gross alpha particle, gross beta particle, hexavalent chromium, lithium, molybdenum, nitrite, radium, silver, strontium, tritium, uranium

Facility last updated on Thursday, March 23, 2017 03:30:54 PM EDT