Mr. Tietje has more than 20 years of engineering and project management experience with a focus in remediation engineering; hazardous waste/landfill engineering; water and wastewater treatment; and geotechnical engineering. Mr. Tietje has been involved in over 30 soil and groundwater investigation and remediation projects, in California, New York, Missouri, and Mississippi for a variety of clients including large corporations in the oil and gas, aerospace, and utility industries; commercial and residential developers; design/build contractors; and the federal government. He is familiar with all aspects of remediation ranging from pilot testing to design and implementation of full-scale systems. Mr. Tietje has successfully implemented numerous remediation technologies including soil vapor extraction (SVE), air sparging, dual phase extraction, advanced oxidation, in situ reactive zone (IRZ), landfill gas thermal treatment, and groundwater extraction and treatment. Mr. Tietje has served as the engineer-of-record (EOR) for complex remediation projects including a large scale IRZ system for treatment of hexavalent chromium and two Brownfield redevelopment projects at hazardous waste landfill sites.