The Virumaa region of Northeastern Estonia has been plagued for years by ground collapses resulting from oil shale mining in the area. It has since been decided that regardless of the form of ownership of affected land, the state must pay for the cost of liquidating damages, and standard projects have been worked out according to which reclamation work in affected areas began last week.
According to Environmental Investment Center (KIK) project coordinator Kadri Haamer-Tibar, mapping conducted with KIK's support revealed more than 80 instances of ground collapse or subsidence, i.e. the ground sinking, at old oil shale mine sites across the Virumaa region. Of these, prioritized will be 15 spots located on 13 properties — which are to be reclaimed by next spring.
"The 13 most dangerous have been selected based on location and based on how deep of collapses they are," Haamer-Tibar explained. "The biggest disturbances to people are caused by those located near buildings on residential land or on cropland."
According to the KIK official, these holes need to be filled because they are dangerous. "Snow falls in there in the winter, or some kind of material is piled on top of it, and someone even just going for a walk in the woods can fall in there," she explained.
Reclamation work got underway last week at the most complex of these sites, located in the Jõhvi Municipality village of Edise, where the forest floor was riddled with trenchlike ditches formed in the collapse of mine shafts.
"This is the most difficult compared with other sites, as the volume of materials is high and there are many meters to fill," Aspen Grupp foreman Meelis Rätsep explained. "That's why we started with this one as well — we're testing how easy or difficult this is going to be. It's a little over a hectare in area here, and some 900 tons of filing materials have been planned for it."
In order to avoid having to draw up a separate project for each hole to be filled, the Ministry of the Environment commissioned four standard projects to be used for the repair of various mining-related collapses.
"If a landowner notices a collapse on their property, they should report it to the Environmental Board, and we can determine together who will repair this collapse and when," Haamer-Tibar said.
"I really hope that this gets sorted out and that this benefits the area," Rätsep said. "I know based on stories that there are quite a lot of these collapses here. Let's hope that there's enough capacity and time to gradually address them."
The repair and reclamation of land on 11 properties in Ida-Viru County and two properties in Lääne-Viru County that have been damaged as a result of oil shale mining operations will run the Estonian state more than €60,000.
Editor: Aili Vahtla