The soil on the ČSA surface mine’s restored areas has arable land parameters as regards contamination
Most, 27 January 2020 – In terms of the presence of pollutants, the remediated areas around the ČSA surface mine have the parameters of organic-quality arable land. They contain only the minimum levels of undesirable trace elements, which otherwise abound in soils in urbanised areas. The research commissioned by the remediation and land department of the ČSA Surface Mine, part of the Sev.en Energy group, has shown this.
“The main purpose of the research that was conducted throughout 2019 was to find the extent to which compost application helps to upgrade soils on restored areas,” explained soil scientist Michal Řehoř from the Brown Coal Research Institute, who has managed the research. Improving soil through compost is one of the few factors available for influencing the conditions for vegetation growth on spoil heaps. Another question for the researchers concerned the lifetime of the soil so upgraded. Various areas on the internal spoil heap of the ČSA quarry, covering some 160 hectares, were tested. “We took the samples every quarter year from two different test areas. On this occasion we also measured trace elements in the soil. The results indicate that soils on spoil heaps are not contaminated and in certain parameters reach the quality of arable land following the application of compost,” added Michal Řehoř.
In terms of trace element levels, the soils were tested for arsenic, cadmium, chromium, nickel, copper, cobalt and some others, to the extent required by the currently applicable legislation. No significantly high levels were found for any of these elements; on the contrary, the levels were deep under the limits for a number of the elements. Arsenic has surprised everyone by the fact that the measured level did not even match the usual values normally found in the whole area at the foot of the Krušné hory Mts. “Arsenic is part of the natural geological background in the soil at the foot of the Krušné hory Mts. and its occurrence is affected by man’s activities only minimally. On the restored areas on spoil heaps, there are Tertiary soils, some 15 to 20 million years old, and at that time Krušné hory as a mountain range did not exist. However, the soil around the towns at the foot of Krušné hory is much younger Quaternary soil with a natural presence of arsenic,” Michal Řehoř explained why soils on restored areas are so clean. “The results of the research have surprised us positively. Today, we can expect that whatever grows on the restored areas, is healthy and free of trace elements,” Jiří Křen, the restoration project engineer at the ČSA surface mine, commented on the results of the research with delight.
Research on additional restored areas will continue in the coming years.
Gabriela Sáričková Benešová
Spokesperson for the Sev.en Energy group
Tel: +420 476 203 141
GSM: +420 725 327 758