David G. Dixon, PG

Principal Geologist


Contact Information

Phone: (415) 967-6000

Email: ddixon@rouxinc.com

Location: Oakland, CA

LinkedIn Profile


Complex Site Assessment and Remediation

Regulatory Compliance

Remediation Cost Estimating

Environmental Regulation

Pesticide Characterization & Cleanup



MIM, Master of International Management - Schiller International University

BA, Earth Sciences (Geology) - University of California, Santa Cruz

David G. Dixon, PG

Principal Geologist

Mr. Dixon is a Principal Geologist and has over thirty years of experience managing and conducting complex characterization and remediation projects. His expertise extends to Brownfield redevelopment; assisting with liability transfer deals; characterization and mitigation of pesticide-impacted land; industrial facility closures; and litigation support and expert testimony for a wide variety of issues, including sites subject to RCRA, TOSCA, and CERCLA regulations, and defense of suits brought under the Clean Water Act. He has extensive experience with groundwater issues, including aquifer testing, extraction, and chemical and bioremediation technologies. His Brownfield redevelopment projects have won Brownfield Phoenix and USEPA Environmental hero awards, and he has assisted clients in obtaining and managing USEPA Brownfield Grants. Mr. Dixon has presented at many national and state-wide conferences on the subjects of environmental due diligence, Brownfield redevelopment, and Clean Water Act issues.


Mr. Dixon holds BA in Earth Sciences (Geology) from the University of California at Santa Cruz, and a Masters in International Management from Schiller University. He is a registered Professional Geologist (PG) in California and the qualifier for Roux’s California Class A General Engineering Contractors License with Hazardous specialty.

representative projects
  • Site Characterization, Remediation and Vapor Mitigation for a Mixed Use Development: Project Principal for the characterization and mitigation of an 85-acre site planned for a new retail center, 1.5 million SF of office, and 2,000 apartment units. The Site was impacted with arsenic, lead, and pesticides in soil and contained soil vapor concerns from an off-site Superfund chlorinated compound release site. Roux prepared plans and reports for the California Department of Toxic Substances Control (DTSC) under a California Land Reuse and Revitalization Act (CLRRA) agreement. The Site soil characterization was conducted at a very high resolution (4-inch intervals), which minimized the excavation volumes and allowed the use of pre-excavation confirmation samples to remove the need for post-excavation confirmation sampling. The remediation involved excavation and relocation of over 100,000 cubic yards of arsenic-impacted soil at the Site. Vapor mitigation systems were designed and installed below residential buildings with potential vapor risks.
  • Site Characterization, Facility, and RCRA Unit Closure/Remedial Oversight: Managed all aspects of the site characterization, remedial feasibility study, and RCRA closure at an 18-acre former electronics manufacturing facility. Assisted the Site owner and their counsel in developing a liability transfer deal, then oversaw the $8MM+ remediation and risk assessment on behalf of the responsible parties. In April 2012, the Site received a No Further Action letter for unrestricted use from the California EPA.
  • Characterization and Remediation of a TCE Plume: Oversaw the remedial alternatives evaluation, design, and implementation of a two groundwater zone TCE plume below active manufacturing facilities. The remediation program, which included chemical oxidation followed by enhanced anaerobic biodegradation, succeeded at reducing PCE in groundwater with an average baseline concentration of 45,000 µg/L to below reporting limits within a year.
  • Shotgun Shooting Range Characterization and Remediation: Managed the characterization, agency negotiation, and remediation at an 18-acre former shotgun shooting range, heavily impacted with lead shot and PAHs. Half of the Site contained Army Corps of Engineers-designated wetlands. Roux obtained Site closure on time and on budget.
  • RCRA Violations and Fine Negotiations: Assisted an industrial client to assess RCRA violations brought on by the DTSC against the facility. Assisted the facility to come into compliance, prepared responses to DTSC claims, and assisted with negotiating fine reductions of over 30%.
  • Litigation Support for Over Ten Clean Water Act Cases: Assisted legal counsel in defending stormwater discharge cases brought under the Clean Water Act for industrial stormwater discharges and facility-specific NPDES permits. Evaluated the technical basis of complaints, prepared expert reports and testimony, assisted facilities to implement best management practices, and assisted with settlement agreements and facility compliance.

  • Litigation Support & Expert Testimony for Historic Landfill Site: Reviewed years of data collected by others and prepared an expert declaration on behalf of the current property owner. Visited the Site and conducted a limited data gap soil investigation. Testified on the nature and extent of soil and groundwater contamination at the Site.

  • Expert Witness and Litigation Support for Property Valuation: Assisted with the litigation support and was the expert witness for a municipality defending a fair market valuation case after an eminent domain acquisition of a contaminated property.

  • Litigation Support/Expert Report for Cost Recovery: Assisted with the litigation support for a property owner seeking to recover cleanup costs from historic hazardous material releases originating from a railroad line at the Site. Conducted soil and groundwater investigations, and reviewed historical records to develop remedial cost estimates and Remedial Action Plan (RAP).