Sludge pond cover at the Victorbur landfill

Situation

The Victorbur drilling mud landfill posed a challenge for the project’s planners and contractors for various reasons. Firstly, there was a very tight schedule: the project was to be completed within a few months. Secondly, the soil had a relatively high pH value (10.6). Furthermore, the landfill had to be remediated with absolute safety, as it is situated in the middle of a protected moorland area.

Solution

In Victorbur, a combined solution proved to be the most appropriate: a highly modular reinforcement material combined with a geotextile proved to be the ideal product for the highly alkaline soil and the required tensile strength. This combined product made it possible to cover the pond with a single large panel. In consultation with the design office, the panel was anchored in an inner and outer trench. This ensured stability within the basin whilst preventing sludge from being forced out into the surrounding nature reserve. The drainage mat laid subsequently ensures that seeping rainwater does not accumulate on the plastic membrane but is safely drained away.

Advantages

By using a large panel consisting of a composite product, sludge ponds measuring 2–3 hectares can be covered quickly and effectively. The additional raw material costs are offset by the reduced labour requirements. The panel stabilises the subgrade so effectively that the base and reclamation layers can be installed without difficulty using snow groomers and long-reach excavators. A geocomposite comprising a high-modulus reinforcement with an optimally integrated non-woven component is extremely durable, e.g. in soils with a high pH value, and also possesses high tensile strength.