Principal Hydrogeologists

James M. Evensen, P.G., C.HG.

Mr. Evensen has over 20 years of professional experience as an expert hydrogeologist, program/project manager, and geophysical assistant. He has been responsible for the management, coordination, scheduling, and budget control of numerous hydrogeologic studies, site assessments, engineering designs, soil and groundwater remediation projects, and construction activities. He is experienced in the areas of regulatory negotiations, legal and litigation support, expert testimony, geological and geophysical interpretation, and computer-applied technologies, including confined- and unconfined-aquifer and vadose zone modeling. His specialties have been petroleum-related remediation and remediation design modeling. Mr. Evensen has been directly responsible for 19 project closures using various methods of remediation for clients such as Chevron USA Products Company, UNOCAL Corporation, World Oil Corp., ARCO Products Company, American Stores Properties, Inc., and numerous independent parties.

Paul D. Horton, P.G., C.HG.

Mr. Horton has over 20 years of professional experience in both the technical and management aspects of environmental projects involving virtually any contaminants including petroleum hydrocarbons, chlorinated volatile organic compounds, PCBs, pesticides, metals, and other chemicals. His project experience has included work at petroleum sites including bulk terminals, pipelines and refineries, general industrial facilities, computer and chip manufacturing sites, chemical manufacturing and bulk storage facilities, and a large Department of Defense facility.

As one of our expert hydrogeologists, Mr. Horton has over 17 years of experience in the application of numerical and analytical groundwater flow and contaminant transport model, the design, implementation, and analysis of aquifer tests, and the general evaluation of site-specific hydrogeologic conditions. He is consistently retained as a technical expert to provide evaluations of complex hydrogeologic systems, and the effectiveness and efficacy of remedial action programs.

Mark Labrenz, P.G., C.HG.

Mr. Labrenz has over 16 years of professional experience as a hydrogeologist, and program/project manager. He has been responsible for the management, coordination, scheduling, and budget control of remedial investigations and feasibility studies and remedial construction projects, including storm water management/NPDES permitting treatment systems. He is experienced in the areas of system design and implementation, regulatory compliance; hydrologic interpretation, and health and safety protocols. His specialty includes RCRA facility decommissioning, including storm water management during decommissioning activities.

Scott Seipel, P.G., C.HG.

Mr. Seipel has eleven years of experience in the environmental consulting industry. He has conducted scoping investigations, mitigation and remediation of sites impacted by petroleum hydrocarbons, polycyclic aromatic hydrocarbons, volatile organic compounds, chlorinated compounds, and metals. Remediation experience includes developing and managing operations, and installation and refurbishing of a large groundwater and vapor extraction, air sparging, and bioventing remediation systems. Site investigation and monitoring experience includes groundwater monitoring for hydraulic, chemistry, and intrinsic biological parameters, and compliance monitoring and reporting for groundwater and storm water discharge under National Pollution Discharge Elimination System (NPDES) permits.