Environmental Investigation & Remediation

ENW’s Environmental Investigation & Remediation Division has performed numerous environmental investigations and designed remedial systems for impacted sites. As former regulators, our professionals are intimately aware of environmental regulations and the data requirements to satisfy state environmental and natural resource agencies. Our environmental professionals have a cumulative 20 years on the staffs of state and federal natural resource agencies, and a cumulative 15 years of experience working in the private sector for environmental engineering companies. 

Work performed for Remedial Investigations (RI) and Feasibility Studies (FS) have the following overall objectives:

  • Identify the hazardous substances which have been released to the environment.

  • Determine the nature, extent and distribution of hazardous substances in affected media.

  • Determine the direction and rate of migration of hazardous substances.
  • Identify migration pathways and receptors.
  • Determine the risk to human health and/or the environment.
  • Identify hot spots of contamination.
  • Develop the information necessary to identify and evaluate potential Interim Removal Measures.
  • Develop the information necessary to evaluate remedial action alternatives and select a remedial action.
  • Generate or use data of sufficient quality for site characterization, risk assessment, and the subsequent analysis and selection of remedial alternatives.


ENW staff have worked on a wide variety of contamination projects, including:

  • Wood treatment plants

  • Service stations and fueling facilities

  • Aviation sites

  • Chemical warehouses

  • Landfills

  • Solvent recycling facilities

  • Lumber mills

  • Abandoned commercial/industrial sites

  • Fleet facilities

  • Metal plating shops

  • Scrapping facilities


Former Auto & Truck Sales Facility Mid-Willamette Valley, Oregon

The facility was active from the 1950s through the 1980s. Two USTs were decommissioned on-site in 1989, in preparation for sale of the property. During the accompanying environmental investigation, a large groundwater contamination plume was discovered which extended over 400 feet. A pool of floating gasoline product extended from the site to other commercial properties on the far side of a busy, five-lane commercial highway. Other discontinuous floating pools were present as well. Neil Woller directed the investigation, modeled groundwater flow and contaminant migration, and evaluated potential remedial scenarios. He designed the remedial system for the site and wrote the Corrective Action Plan accepted by the Oregon Department of Environmental Quality.

Site Response Department of Environmental Quality, Oregon

As Senior Hydrogeologist for the Western Region of the Oregon Department of Environmental Quality, Neil Woller was Project Manager for several high priority contamination sites. He negotiated with representatives of responsible parties to perform necessary characterization, reviewed submittals from technical consultants including Scope of Work documents, Remedial Investigations, Feasibility Studies, and Risk Assessments. He negotiated the requirements of administrative and judicial Orders to complete investigations and remedial actions. He reviewed analytical data and field activities for completeness and compliance with QA/QC requirements.

Service Station Clatsop County, Oregon

Lynn Green was the Senior Scientist for the cleanup and monitoring work conducted on-site, addressing the historical release of both gasoline and used oil from several USTs at this service station. Lynn supervised the aquifer characterization activities and performed groundwater modeling to estimate the mobility of the released contamination. Additionally numerical modeling was used to estimate the ground water plume geometry to assist in further remedial activities.

Former Recycling Facility Multnomah County, Oregon

Lynn Green was the Senior Scientist for the groundwater investigation conducted addressing the historical release of gasoline, diesel, pentachlorophenol, and polychlorinated biphenyls released from several abandoned USTs. Mr. Green supervised all aquifer characterization activities.