Water samples collected from various locations demonstrate that coal ash released from a landfill under construction has not impacted water quality in Sutton Lake in Wilmington, North Carolina (USA).
In addition, the company continues to monitor water levels in the Cape Fear River, which flows near Sutton Lake, a cooling pond built by the company to support plant operations. Before, during and after the storm, the company has been managing water levels inside the cooling pond, performing maintenance and conducting regular inspections to help ensure it operates safely. That work continues as the river levels continue to fluctuate.
Lake water quality remains good
Earlier in the week, Hurricane Florence, which produced a historic rainfall totaling more than 30 in. at the plant, caused several areas of significant erosion at the coal ash landfill currently under construction.
Based on the company's current estimate, water and approximately 2000 cubic yards of soil and ash eroded from the landfill. Much of the nonhazardous material, which would fill about two-thirds of an Olympic-sized swimming pool, was captured in a perimeter ditch around the landfill, and cleanup work has already begun. As the company has previously reported, a very small amount of ash made its way off plant property to an adjacent industrial site, which is being cleaned up.
During the hurricane, while erosion was continuing at the landfill, the company began collecting water samples at various locations on the property and near the outfall to the river. Initial test results clearly demonstrate that the presence of coal ash constituents decreased as the water made its way to Sutton Lake. The company continues to gather water samples and share those with regulators.
Site inspections have identified cenospheres in Sutton Lake, but water sample results show no evidence of a coal ash impact to the lake or the water entering the river. Cenospheres are lightweight, hollow beads comprised primarily of alumina and silica that are a byproduct of coal combustion. Sample results are consistent with recent years of data. Water quality remains well within state permit standards designed to protect people and the environment.
Duke Energy photos provide views of the facility and show that most of the ash stayed in place or moved to other cells within the landfill footprint and sediment pond.
Once construction is completed, the landfill sections will be permanently capped with a waterproof, synthetic barrier and closed with soil and vegetation so erosion of this nature is much less likely to occur.
The company took a number of steps before the storm to prepare, including positioning field staff, equipment and materials at sites. Its strong progress in ash basin closure was instrumental in lowering ash basin water levels to better accommodate significant rainfall.
Ash basins operate safely
Importantly, Duke Energy's coal ash basins continue to operate safely. As the company has previously reported, three small inactive basins at the H.F. Lee Plant in Goldsboro are flooded, which was expected. Because they are covered in forest and vegetation, it is expected that minimal amounts of ash could be displaced, and crews continue to actively survey that area. Conditions at other plant locations are improving as rivers and flooding recede.
Read the article online at: https://www.worldcoal.com/power/20092018/update-on-duke-energys-sutton-plant-following-hurricane-florence/