Margaret Gentile, Ph.D., PE, principal engineer and in situ reactive treatment lead for Arcadis North America, also an associate vice president at Arcadis, has 10 years of consulting experience. She specializes in biological treatment processes, investigation and remediation of metals, including hexavalent chromium and arsenic, and large plume remediation. She holds a B.S. in chemical engineering from the University of Marlyand, and an M.S. and Ph.D. in environmental engineering from Stanford University.