Fluid storage tanks have many applications within the mining industry including at well heads and fluid processing facilities, for irrigation water storage, dust suppression water storage, construction water, potable water and grey water at camps. They are also suitable for wash down bays.
Our client used bidim C Range conductive geotextile as part of its lining containment system on two double lined brine water storage tanks to deliver significant savings in design time, construction time, expenditure and environmental impacts compared with traditional regulated dam construction.
The tank lining system retains water and assists in the management of potential leaks within the tank. The lining system, which was installed on the base and walls, included:
Traditional leak detection testing requires wetting of the geotextile in each layer beneath a geomembrane, adding cost and complexity to the construction, especially on remote sites where water is difficult to obtain.
In addition to the cost of trucking in water, the traditional testing method using wetted non-conductive geotextile can lead to false reports of the presence of a leak due to the presence of water in the geotextile. bidim C does not require wetting and can eliminate these false positives.
The occurrence of false positives has been noted to have previously led to the perception of leaks being present, which in turn leads to the need to drain the dam (or tank) and retest. The draining, transportation, and storage of fluid from a tank under these circumstances is extremely costly and therefore there is a high motivation to avoid this taking place. While the engineers who undertake the installation might assert that the tank is in fact leak free, they have no alternative but to respond to their customer’s need to re-check for leaks.
The testing organisation conducted two leak detection tests on the tanks: one to the secondary liner which was tested using the traditional wetting methods and copper wires one to the primary liner using bidim C conductive geotextile.
Our client’s alternative to bidim C for leak detection is to lay bidim geotextile and copper wire and then wet the bidim. This has the following challenges:
Using a conductive bidim C underneath the secondary liner would deliver the same advantages for testing the secondary as it does for the primary.
One testing organisation estimates the main causes of holes found in the liner: