Former National Semiconductor CERCLA Site
Langan was tasked with redesigning the groundwater treatment system at the former National Semiconductor (now Texas Instruments) CERCLA site. The original network of groundwater extraction wells was installed in 1984 to control plume migration and remove mass at a large chlorinated solvent plume, and groundwater was extracted and treated using a series of air stripping towers and then discharged to the storm drain via a man-made lake. Langan developed a system to replace the aging air stripper towers, which was designed to be health protective with a high degree of efficiency and environmental sustainability. The redesign consisted of a single air stripper unit, and to help meet the client’s corporate sustainability goals, the new system discharges treated water to the client’s reverse osmosis system for reuse in onsite cooling towers. The client is also working on other reuse scenarios, such as landscaping with reclaimed water, to further increase the amount treated groundwater reclaimed onsite.