PRECISION CLEANING TOXIC SUBSTANCES AFTER EXPLOSION

Elia is the operator of the Belgian high-voltage grid. To operate the electricity grid, Elia uses a so-called Gas Insulated Switch Gear (GIS) system. In that system, SF6 gas (sulfur hexafluoride) acts as insulation for the switch gear. This gas can cause asphyxiation if inhaled and is highly toxic when heated. After an explosion at the Elia building in Lillo, there was therefore no time to waste. The environmental department of Mourik was asked to act quickly.

CLEANING IN STAGES AND REMOVAL OF TOXINS

The toxic substance had covered all surfaces in the building. Given the nature of the work, we tackled this project with specialists in several disciplines: environmental services, construction and asbestos removal. We set up a hermetic zone, equipped with an extractor and an access shaft, to ensure the cleanup was safe and effective. First we cleaned the first floor of the GIS building, using soft cloths and a vacuum cleaner with special attachments to prevent damage to the installations and cables. This was followed by the basement. We sealed all openings in the floor to prevent toxic dust from swirling up to the first floor during cleaning. The basement floor was covered with a layer of contaminated sand. We sucked up this layer with a soil vacuum truck and transported it to an approved processing centre.

Safety

We drew up the working method and all the safety protocols that go with it, in close consultation with Elia's safety people. We established a hermetic zone and carried out the cleaning in phases, each time with a thorough inspection by Elia and then release for the next phase. After completing all cleaning works and releasing the entire GIS building, we collected the waste in special containers and transported it to an approved treatment facility.

Mourik already had an ongoing framework agreement with Elia. The result of this cleaning meant an additional deepening of that. We have since cleaned four other buildings, including the GIS buildings in Machelen and Mons. This is a good example of our pooled expertise and the go-getter mentality that clients appreciate in Mourik.