Brief
This public procurement contract involves the remediation of historical ecological contamination in the Mníšek pod Brdy area, specifically at Halda, Bažantnice, and surrounding locations. The contamination originates from the former operations of the KOVOHUTĚ plant, resulting from long-term waste disposal from metallurgical production and the leaching of heavy metals and salts. This contamination has permanently degraded the adjacent habitat (Bažantnice) and has affected several other sites, including domestic wells and monitoring boreholes. Additionally, a local fishery pond is at risk. The construction site is located in the cadastral area of Mníšek pod Brdy (697621), covering approximately 60,000 m2, situated about 3 km east of the center of Mníšek pod Brdy, adjacent to the former KOVOHUTĚ site. The planned work will involve land parcels numbered 1965/28, 1965/27, 1965/112, and possibly 1966/1, 1965/105, 2070/5, and 2070/6, if scattered waste from the dump is found on these lands. The northern edge of Bažantnice is bordered by waste dumps from the KOVOHUTĚ plant, including a vanadium tailings pond (partly used later as a landfill for aluminum sludges), with solid waste dumps to the south – an old landfill (mainly aluminum production waste) to the east and a vanadium and ferrovandium slag dump to the west, which has mostly been excavated. The Bažantnice area, including the reclaimed aluminum sludge landfill, vanadium tailings pond, and aluminum sludge dump, is located east of the KOVOHUTĚ operational buildings. To the north and east, there is cultivated agricultural land, while the KOVOHUTĚ site is fenced off to the west. The southern edge features a partially wooded area known as Bažantnice, bordered by the Městský stream. To the southeast, Bažantnice adjoins the Sýkorník pond. The remediation work will include cleaning the contaminated lagoon area, demolishing the settling tanks in the landfill, dismantling concrete panels, dividing the lagoon into eastern and western sections with a dividing embankment, and sealing the bottom of the eastern lagoon to prevent groundwater contamination. The project also involves relocating all contaminated waste from the western lagoon to a sealed area, which will then be covered with geomembranes and bentonite/foil sealing, functionally connected to the underlying insulation layer. Additionally, terrain modifications and technical and biological reclamation will be carried out around the sealed lagoon. During the remediation work, the concentration of various contaminants will be monitored at selected monitoring sites, wells, boreholes, and surface water. The existing monitoring system will be checked, and unnecessary objects will be removed. Due to the nature of the contamination and remediation intervention, the project will not conclude with an updated risk analysis but with long-term monitoring of contaminant concentrations in the vicinity of the remediated and reclaimed area. Monitoring will include indicators such as pH, conductivity, the presence of ions (Ca, Na, Al, Co, Cu, Fe, Mn, Mo, Ni, Se, Sb, Be, Zn, Pb), variable oxidation states of V, BIII and CrVI in compounds, total CN, CHSKMn, F-, NO2-, NO3-, Cl-, SO42-, and NH4+.