Rapid infiltration basin
Rapid infiltration basin
The rapid infiltration basin represents an ideal setup for simulating MAR scenarios under natural conditions (climate shift during day and night; reduced preferential flow along walls). The general setup covers an area of 20 m2 and a depth of 1,50m and it includes a 1,215m2 infiltration basin located in the center. The unit can be used with homogenous packing materials (approximately 50 tons of soil) or it also can be filled with layers of different soil textures.
12 observation points can be distributed spatially according to the purpose of the experiments. The actual configuration consists in 4 layers of measurement where the sensors are located in strategic points under the basin in order to monitor the following parameters in time:
- Tension (0 - -85kPa)
- Water content with FDR sensors (0 – 100 %)
- Temperature (-40 – 60°C)
- Electrical conductivity (0.001 – 4 mS/cm)
All the data is stored in a UGT Datalogger with CMOS microcontroller, which is installed next to the infiltration basin. The time interval in which it can take the measurements can be programmed from 1 second to 1 hour.
For more specific analysis in the lab (e.g. ions, metals, pH, DOC) each observation point is equipped with a suction cup (0,89 bar ceramic), which can pump water samples to the surface by applying underpressure with the vacuum pump integrated in the Datalogger.
We have a fixed pump connection system (T.I.P. AJ 4 Plus – 5 500L/h) that delivers fresh river water directly from the Elbe to the reservoir next to the infiltration basin. Pumping times and duration can be controlled by a timer, depending on the hydraulic necessities of the running experiment. A second pump is located in the reservoir to feed the infiltration basin. This pump has an adjustable pumping rate that helps to set the wished hydraulic loading rate of the experiment. A last pump in the reservoir works as a mixer of the pumped water in order to avoid any particles deposition.