DHL Wilmington Airpark (ILN)
Wilmington, Delaware

As the hub for DHL's North American operations, the airpark houses 7,500 employees and conducts cargo operations around the clock, with the ability to sort more than 1.5 million packages nightly. The massive ramp area has space for 125 jet aircraft and handles over 250 aircraft operations daily. In a typical year, ILN uses more than 400,000 gallons of deicer fluid. A comprehensive stormwater collection and deicer treatment system designed by GS&P was recently upgraded by incorporating state-of-the-art monitoring and treatment technology to maintain NPDES compliance. The collection system utilizes online measurements to segregate flows into clean, low concentration and high concentration streams. The low and high concentration streams are detained in open basins and are blended together for controlled treatment in an onsite reciprocating subsurface wetland treatment system.