Rick Ahlers is a Technical Expert with Arcadis, located in San Diego, California. He has been practicing groundwater and vadose-zone hydrology for more than 21 years. At Arcadis since 2002, he has worked for many Oil and Gas clients on sites ranging from service stations to pipelines to bulk terminals to refineries as well as for Industrial clients where LNAPL and chlorinated DNAPL source zones are the concern. Using emerging assessment techniques for petroleum hydrocarbon sites including natural source zone depletion (NSZD), natural attenuation of hydrocarbon and oxygenate groundwater plumes, and NAPL transmissivity allows him to evaluate alternative endpoints for NAPL management. He also uses experience gained across many sites with more common remediation technologies such as AS/SVE, MPE, and skimming, to select the best technology for the site and project and guide implementation to efficiently achieve remedial goals. Rick leads the global NAPL management community of practice in Arcadisí Technical Knowledge and Innovation network. Rick started his career at Lawrence Berkeley National Laboratory characterizing and modeling multi-phase flow in porous and fractured media. Rick has been active in the ITRC since 2006 first as a member of the BioDNAPL team and then as a member of the LNAPL team. He is also a member of the scientific advisory board for the AEHS West Coast International Conference on Soil, Water, Energy, and Air. Rick earned a bachelorís degree in physics from Occidental College in Los Angeles, California in 1990 and a masterís degree in Civil Engineering specializing in groundwater hydrology from the University of California, Berkeley in 1994. Rick is a California Registered Civil Engineer.