On December 22nd,2008 there was a huge disaster at TVA (Tennessee Valley Authority) facility in Kingston, TN, Usa. A massive spill of coal ash, due to the collapse of the dike used to contain fly ash, occurred at 01 hours neighbourhood the dewatering area. The spill released about 5.4 millions cubic yards.
The ash and water spread over beyond 300 acre area adjacent to the plant damaging homes and infrastructures. Some flowed into the Emory and Clinch rivers and the Watts B. Reservoir devastating the local aquatic ecosystems.
The ash covered portion of the nearby streets and the railroad tracks by which coal is supplied to the plant. About 600 families were affected by property damages. The environmental disaster has been described as one of the worst in U.S. history. TVA initiated clean up at once mobilizing large number of heavy equipments (backhouses, bulldozers, trucks) and personnel.
Booms were placed in the rivers to contain ash migrating downstream (boats
were used to vacuum the floating ash). The heavy equipment was also used to clear waterways to allow creeks to drain that had been blocked by the fly ash release. Since January 2009 several actions have been taken to decrease the potential for airborne dust. TVA cost estimates for the clean up was 525 -825 million dollars which do not include long term remediation costs. Upon the notification of release TVA, EPA, TDEC (Tennessee Department of Environment) and others agencies joined in a coordinated response structure (Unified Command). Sampling ash, water, soils and air programs carried out by TVA, EPA, TDEC started on December 22nd under the supervision of the Unified Command. On February, 20th 2009 a report prepared by Tetra Tech for EPA summarized the results of the survey. Water sampled by municipal and private groundwater continue to meet the quality standard as the tests carried out on air quality. Analytical results from river sampling indicated that all the analyses were below the standard limits except for the arsenic. For what concerns radioactivity, sampling analysed by Duke University indicated that the ash has radiation levels above those reported by the EPA for typical coal ash.

Torna all'articolo