The Hrabůvka slag-heap is a former dump site for coal mining waste, covering an area of 100 hectares and located in the southern part of Ostrava.
The history of the Hrabůvka slag-heap dates back to around 1890. It was created on the site of gardens and fields belonging to local people, and it was used to dump mining waste from the nearby Louis coal mine (currently the Jeremenko mine).
The slag-heap (owned by the VÍTKOVICE, a.s. company) remained in use until June 2014. At the end of 2014 a project was launched to stabilize subterranean thermal processes inside the slag-heap; the project was funded by the national subsidy programme for the revitalization of the Moravian-Silesian Region, with around 140 million CZK paid by the Ministry of Finance. The project was completed in December 2016.
The purpose of the project was to stop waste material inside the slag-heap from burning. Bore-holes were drilled to enable the fires to be extinguished by injecting inert material. A water reservoir (approx. 4.5 ha, with a capacity of 180 000 m3) was also built. This reservoir ensures that no air can penetrate into the lower layers of the slag-heap. In the northern part of the site, a metre-deep artificial lake has been created, covering an area of 35 m3, which will help to create a biotope for aquatic plants and animals. A layer of earth has also been deposited over an area of approximately 12.3 ha to prevent air penetration. Landscaping work has been carried out (including the addition of topsoil), and the site has been planted with greenery.
The level of the terrain to the east and south-east of the slag-heap has been lowered, a small reservoir has been created as a habitat for animals living at water margins, and various forms of greenery have been planted (wetland plants, plus 269 trees and shrubs).
Temperature monitoring is currently taking place at selected locations within the site, and ground subsidence is being measured in areas where earth and topsoil have been added in order to ascertain the effectiveness of the process.
From November 2015 to March 2017 the next stage of work at the slag-heap took place: the clean-up of hazardous waste dumps (mainly oil sludge and metal-bearing sludge) and their replacement by a new layer of earth and topsoil. A total 8 400 tonnes of contaminants have been removed from the site, and the area has been planted with grasses, trees and shrubs.
The owner of the site – VÍTKOVICE, a.s. – has now fully complied with its legal responsibilities as set out by the Ostrava branch of the Czech Environmental Inspectorate.
In accordance with Ostrava’s land use plan, the site can now be used for sports facilities and leisure activities.
Photos: Vítkovice a.s.; Petr Přendík