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Improved Exfiltration Apparatus


The invention is an exfiltration apparatus that removes pollutants from runoff captured off the roadways. Pollutants may include oils soil tire rubber metallic traces nutrients organic chemicals and compounds among others. Such materials lead to the clogging of filtering trenches by the roadside a situation that worsens during the snowmelt and heavy rains. The device construction consists of two main parts a base and a removable top layer. The top portion contains the first filtering layer which removes the large suspended particles from the run-off and a metallic grate to protect it. The base has bottom and side portions that define the flow of the liquid and a second filtering layer which filters the finer particles from the liquid. A geotextile material serves as a barrier between thetwo filtering layers and between the second filtering layer and the drain. The filtration device is not attached to the road construction and can be easily removed for cleaning enabling low maintenance. A variety of materials such as porous concrete sand porous asphalt garnet granular plastic or activated carbon can be used for filtering.


The technology provides a number of benefits over existing exfiltration techniques: 1) High flexibility in terms of physical configuration; permitting alterations in device size fabrication of the base from one or several pieces provisioning of a sealing element use of an number of filtering layers and use of a range of filtering materials to meet specific cost or functional requirements. 2) Enhances the cost effectiveness of the highway drainage system by reducing the requirement of drainage trenches being replaced or cracked open due to clogging. Also maintenance costs are lowered significantly. 3) Reduces damage to the drainage mechanism by providing sufficient strength to withstand heavy traffic conditions. (ease of maintenance) 4) Eliminates any requirement of having to dig the roadside for cleaning and replacing of the filtration device due to its modular de-attachable construction.

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