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Multnomah County, Oregon
Environmental Services in Multnomah County, OR
Environmental site assessments and construction-phase environmental support that keep transactions and projects moving without surprises. Multnomah County is covered on a project basis through our Seattle, WA regional hub.
- Dispatched from
- Seattle, WA regional hub · project-based mobilization
- Lead time
- Set in the proposal, with mobilization planned around your pour and earthwork schedule
- Laboratory
- Sugar Land, TX laboratory under chain of custody, or a mobile laboratory for large projects
- Reporting
- Reviewed and issued under a documented quality system; formatted for owner, engineer, and building-official review
- Serving
- Multnomah County, OR — Portland, Eugene, Salem
- Coverage
- Oregon statewide · 27 regional hubs
- Technicians
- ACI- and NICET-certified field staff; licensed professionals in Oregon
- Call us
- (346) 420-5425
Scope
Environmental services in Multnomah County
- Phase I Environmental Site Assessments for acquisitions and refinancing
- Phase II subsurface sampling when a Phase I identifies recognized environmental conditions
- Construction stormwater support: SWPPP compliance inspections
- Soil management screening for export and import of fill material
Full scope, standards list, and pricing basis: Environmental Services.
Local conditions
Environmental conditions in Multnomah County
Multnomah County sits at the confluence of the Columbia and Willamette rivers, a geography that shaped the region's industrial history and left a legacy of brownfield sites, former rail corridors, and flood-plain properties across Portland and the surrounding municipalities. Environmental due diligence is not optional in this market — lenders, Oregon DEQ, and prospective buyers routinely require documented assessments before transactions close or ground breaks. Our firm provides Phase I and Phase II Environmental Site Assessments, as well as construction-phase environmental support, for contractors, developers, and engineers working across the county. Coverage is dispatched through our Seattle regional hub on a scheduled and project-based basis, coordinated to meet your project timeline. Every assessment follows ASTM E1527-21 for Phase I work, and our laboratory operates under a documented quality system. Whether you are managing a redevelopment on a former industrial parcel or need oversight during remediation-adjacent construction, we bring the technical rigor the project and regulators expect.
Much of Multnomah County's developable land lies within or adjacent to Willamette and Columbia river floodplains, where high groundwater tables and alluvial soils can complicate subsurface investigation and increase the potential for contaminant migration — factors that influence both Phase II scope decisions and construction-phase environmental monitoring plans. Oregon DEQ oversight adds a state-specific regulatory layer that can affect cleanup standards and reporting requirements beyond federal baselines.
FAQ · Multnomah County
How does Oregon DEQ involvement affect the Phase II scope or cleanup standards on a Multnomah County site?
Oregon DEQ administers its own voluntary cleanup program and cleanup rules under OAR 340-122, which can set risk-based cleanup levels that differ from federal EPA defaults. When a Phase II identifies contamination that may require remediation, the investigation scope — sampling locations, laboratory parameters, and reporting format — is often shaped by DEQ guidance to support a No Further Action determination or an approved cleanup plan. We structure Phase II work with that pathway in mind.
The site I am evaluating near the Willamette River has a high water table. How does that affect subsurface sampling during a Phase II?
High groundwater, common in the alluvial deposits along the Willamette and Columbia corridors, requires that soil borings and monitoring well installations account for potential caving, sample disturbance, and the need for groundwater-specific analytical suites. Boring advancement methods and decontamination procedures follow applicable ASTM standards, including ASTM D1586 and D6169 where relevant, and sampling protocols are selected to preserve sample integrity in saturated conditions.
What construction-phase environmental monitoring services do you provide when active remediation or contaminated soil is encountered during grading?
During construction on sites with known or suspected contamination, we provide soil screening, field photoionization detector (PID) screening, sample collection for off-site disposal characterization, and documentation to support the contractor's waste manifest requirements. This work coordinates with the geotechnical and special inspection program so observations are integrated, not siloed. Scheduling is arranged through our Seattle hub on a project-specific basis.
Which office covers environmental in Multnomah County, OR?
Field work in Multnomah County is dispatched through the Seattle, WA regional hub, about 145 miles away. Laboratory testing is performed in Sugar Land, TX under chain of custody, or in a mobile laboratory mobilized to large Multnomah County projects.
Are the technicians you send to Multnomah County certified?
Field sampling and testing in Multnomah County are performed by our ACI- and NICET-certified technicians. Environmental engineering and professional services are delivered with professionals licensed in Oregon, coordinated under one proposal.
Scheduling & proposals
Need environmental services in Multnomah County?
Call to schedule a technician, or send project documents for a written proposal.