The 241-U Tank Farm Evapotranspiration project consists of the installation of a drainage basin system to capture precipitation runoff once the asphalt surface barrier is placed over the 241-U Farm. The project scope included the excavation of the basin, which consisted of a 55,640 sq ft depression with sloped walls. The drainage system includes two catch basins inside the farm, two storm water manholes, and one separator outside the fence of farm.
Once the precipitation is collected in the catch basins, it will travel to the drainage basin to the west of 241-U Farm. In the basin, the water flows through the hundreds of feet of buried pipe. The basin is comprised of a layer of non-woven geotextile on the basin floor, followed by 40-mil EnviroMax smooth liner, followed by another layer of non-woven geotextile to protect the liner, and a 3 ft backfill layer at last. The purpose of the basin and liner system is to accommodate the runoff from 241-U Farm and prevent the water from going into the ground, respectively.
Once the basin installation was completed, Elite placed 500 tons of ballast rock on the interior slopes of the basin and 500 tons of 1 ¼” minus crushed rock on the vehicle access ramp and berm. Natural gas will be incorporated into the basin in the future.