Tennessee Valley Authority (TVA) employees and contractors are conducting an environmental investigation to determine the nature and extent of elevated levels of arsenic and lead discovered in a few shallow groundwater monitoring wells at the TVA Allen Fossil Plant, a coal-fired power plant near Memphis operated by TVA.
In May, TVA notified the Tennessee Department of Environment and Conservation (TDEC) that a few shallow groundwater monitoring wells near the plant’s East Ash Pond – sampled as part of the coal ash pond closure program – showed elevated levels of arsenic.
Now TVA is working under the direction of the remediation team at TDEC, which is reviewing the recently submitted investigation plan. Though formal sign-off has yet to occur, work moves ahead to put people and processes in place to help determine the nature and extent of the contamination.
“Drinking water at the plant, and throughout Memphis, is not impacted by the arsenic or lead found at Allen,” said Jacinda Woodward, TVA’s Senior Vice President of Resources and River Management. “Our priority remains to protect human health and the environment.”
Memphis Light Gas and Water’s Gale Jones Carson agrees. “Water sampling tests that were conducted by a certified independent lab last month showed no detectable traces of arsenic or lead in the community’s treated drinking water supply,” she said.
TVA has contracted with experts from the US Geological Survey and the University of Memphis to map the underlying geology and to learn more about the movement of groundwater at the site. This information will help resolve questions of possible migration of the arsenic into the deep Memphis Sand Aquifer.
As another part of this effort, TVA is installing more than 20 monitoring wells around the coal ash storage area. These wells will vary between 20 – 160 ft deep. The information from these wells will help investigators define the shape and depth of the arsenic plume.
The remedial investigation will take a number of months to complete. The investigation and installation of monitoring wells are in progress, and completion of field work is anticipated late fall. Submittal of the remedial investigation report to TDEC is expected this winter.
The shallow monitoring wells where the arsenic contamination was found are more than a half mile away from TVA’s deep cooling water wells at the Allen natural gas plant site. The groundwater at the gas plant is separated from the Memphis Sand Aquifer by a thick, protective layer of clay.
TVA does not plan to use the Allen gas plant cooling water wells for plant operations until additional data from the remedial investigation is obtained to support safe use.
TVA will continue working to investigate the location, nature and extent of the issue – and then will do what it takes to remedy the situation. “At TVA, we work to address threats to public safety and the environment,” Woodward said. “Stewardship is at the heart of TVA’s mission. We will determine the nature and extent of this problem and do our share to clean it up.”
Read the article online at: https://www.worldcoal.com/power/25082017/tva-conducting-environmental-investigations-at-allen-fossil-plant/