Dr. Stephen J. Cullen is a Senior Vice President and Principal Hydrogeologist with Daniel B. Stephens and Associates. Dr. Cullen has over 28 years of professional experience in groundwater and soil investigation, monitoring, modeling, and data interpretation at industrial, municipal, and federal project sites.

Dr. Cullen has previously served on the faculty of the University of California, Santa Barbara, as Associate Research Hydrologist at where he was the Lead Scientist at the Vadose Research Laboratory. He also lectured on groundwater and soil environmental contaminant issues in the departments of Geology, Engineering, and Geography. He is a registered Professional Geologist (California), Registered Environmental Assessor, Level II (California), a Certified Environmental Manager (Nevada), and a Certified Professional Soil Scientist (ARCPACS).

Dr. Cullen has authored over 75 publications on environmental subsurface modeling, monitoring, and remediation including the widely acclaimed textbook “Handbook of Vadose Zone Characterization and Monitoring”. Dr. Cullen has made numerous presentations on these topics including his invitation to present the keynote speech to the First International Congress on the Impacts of Industry on Groundwater held in Cernobbio, Italy. Dr. Cullen is noted for his professional contribution in co-authoring the watershed “UC Lawrence Livermore (LLNL) Reports” in 1995 that established the precedence for risk-based closures at petroleum hydrocarbon sites in California based on the natural attenuation and intrinsic degradation of petroleum hydrocarbons in the subsurface environment.

Dr. Cullen has provided the technical expert opinion and testimony in the resolution of numerous legal matters involving subsurface contaminant transport, vadose zone characterization, and groundwater monitoring and remediation. Dr. Cullen has served in numerous high-profile legal cases involving a range of environmental issues, for clients that range from Fortune 500 companies to governmental entities and smaller family trusts. Dr. Cullen provided the primary expert testimony for a trial defense effort that was named as one of the top 20 defense trial victories in 2002 by the National Law Journal.

Daniel B. Stephens, Ph.D., P.Hg., P.G., is the Principal Hydrologist and Chairman of the Board of Daniel B. Stephens & Associates, Inc. (DBS&A). Dr. Daniel B. Stephens is an internationally recognized expert in hydrogeology, including water resources development, water quality and vadose zone hydrology. He has over 25 years of experience on projects ranging from site characterization to mathematical modeling of flow and transport. Dr. Stephens holds a Ph.D. in hydrology from the University of Arizona, an M.S. in hydrology from Stanford University, and a B.S. in geological science (with honors) from Pennsylvania State University. His expertise and formal training is a blend of hydrogeology, soil physics, and geotechnical engineering. Key areas of expertise include: hydrogeology, groundwater basin analysis, recharge, stream-aquifer interaction, impairment, vadose zone hydrology; allocation of responsibility; contaminant source identification; contaminant fate and transport analysis; applications of groundwater and vadose zone models; unsaturated flow; site characterization and monitoring; natural resource damage; and remedial action programs.

Dr. Stephens has experience in federal and state courts, as well as in administrative hearings on water rights and groundwater and soil contamination cases. He has given numerous depositions and provided expert testimony at trial. Additionally, he has served as a technical liaison to a mediator of a potentially responsible party (PRP) group. Dr. Stephens has been involved in a wide range of contaminated sites, including sites contaminated with chlorinated solvents (PCE, TCE, etc.), perchlorate, NDMA, petroleum hydrocarbons, MTBE, oil field brine, wood treating chemicals, heavy metals, and pesticides, among others. He has published over 100 articles in national and international scientific journals and conference proceedings. Additionally, he is the author of a book entitled Vadose Zone Hydrology which was published in November 1995.

Mr. Neil Blandford, P.G., is the Vice President of Water Rights Services. Mr. Blandford has an M.S. in groundwater hydrology from the New Mexico Institute of Mining and Technology and a B.A. in environmental science from the University of Virginia. He specializes in numerical simulation of groundwater flow and contaminant transport; water rights analysis and water supply investigations; geostatistics and aquifer testing methods; wellhead protection area delineation; and remediation well field design.

Mr. Blandford has provided expert testimony on projects involving new appropriations, water right transfers, return flow analysis, basin adjudication, water quality issues at mine sites, salinity encroachment, and National Resource Damage claims related to groundwater resources. He has more than 20 years of experience in the quantitative analysis of water resources in New Mexico, Arizona, Texas, and Florida. Mr. Blandford has also been integral in the development of several fate and transport computer codes for the U.S. Environmental Protection Agency.

Dr. Nicole T. Sweetland is Senior Vice President of Expert Services at DBS&A. Dr. Sweetland received her B.S. in Geology from the University of California, Santa Barbara, and her M.S. and Ph.D. in hydrology from the University of Arizona. She specializes in hydrogeology, environmental forensics, and contaminant fate and transport. Dr. Sweetland's work depends heavily on technical tools, such as databases, GIS, environmental forensics, and groundwater fate and transport modeling, to perform complex technical analyses. Dr. Sweetland works closely with her clients to develop effective strategies to resolve environmental concerns related to contaminated soil and groundwater and is able to quickly integrate complex technical and legal issues and lead her team in providing efficient solutions for her clients. Her contributions to and respect by the scientific community are demonstrated through articles published in peer reviewed journals and presentations at technical conferences and through serving on the editorial boards of Ground Water (current), Environmental Forensics and Ground Water Monitoring and Remediation.

Mr. Jordan Kear, P.G., C.Hg., is a Senior Hydrogeologist with Daniel B. Stephens & Associates, Inc. He holds an M.S. in geological sciences from California State University, Northridge and a B.S. in geological sciences from the University of California Santa Barbara.

Mr. Kear has provided expert technical support to counsel, declarations, and testimony on a wide range of hydrogeologic topics. These have included water well location, design, development, rehabilitation and maintenance; fate and transport of MTBE in the vadose zone and groundwater; evaluation quarry blasting effects on aquifers and water wells; migration of 1,2-DCA, PCE, and TCE in groundwater; groundwater supply assessments; and the effects of well condition on the production of water containing natural and anthropogenically derived contaminants.

Kenneth Calhoun is Manager of Geographic Information System (GIS) services at Daniel B. Stephens & Associates, Inc. (DBS&A) with fourteen years of experience in GIS technologies specializing in GIS applications for land use, environmental, and water resources management. GIS related projects at DBS&A include the use of satellite imagery and historical aerial photography for land use classifications, environmental database development, stream flow and terrain analysis, and general civil engineering support for various groundwater contamination litigation, water resource and water rights projects. Mr. Calhoun earned his M.A. and B.A. in geography from the University of New Mexico and has published six articles and given ten presentations at GIS-related conferences.

Mr. Calhoun has served as Project Manager for many GIS projects, including a critical project for the State of Texas Water Development Board that used GIS to analyze sites within the state that would be suitable for groundwater banking, and has served as GIS technical lead on numerous litigation projects. He is currently the project manager for a multi-year contract to develop a comprehensive web-accessible, GIS-based database management system for projects associated with habitat restoration, water management, and scientific investigations within the Middle Rio Grande basin for the U.S. Army Corps of Engineers and the Middle Rio Grande Endangered Species Collaborative Program. He is recognized as a qualified expert by the United States District Court and has been retained by the United States Attorney’s Office to provide expert opinions on land trespass cases.

Mr. John Burkstaller, P.E. is Vice President and Water Resources Division Manager. Mr. Burkstaller is a civil engineer with more than 30 years of experience in environmental and water resource issues related to the Clean Water Act, the Endangered Species Act, and the Safe Drinking Water Act. He holds M.S. and B.S. degrees in civil engineering, both from New Mexico State University. Key areas of expertise include water resources planning; water and wastewater treatment, planning and design; aquifer storage and recovery; water chemistry, including arsenic treatment planning; and water desalination design and planning.

Mr. Burkstaller has served in key leadership roles for water utilities, environmental regulatory agencies, and environmental engineering firms in New Mexico, Nevada, Texas, and California. Mr. Burkstaller has been involved in several landmark water policy decisions in the western states. On behalf of the City of El Paso and the Western Coalition of Arid States he participated in litigation and settlement negotiations with the U.S. Environmental Protection Agency and the U.S. Attorney General’s Office regarding the EPA’s final Arsenic Rules.