Phase II Environmental Assessments
A Phase II Environnmental Site Assessment (Phase II ESA) is an “intrusive” investigation, which includes the collection of soil, vapor, or groundwater samples in order to determine whether a site is contaminated. Those contaminants can include petroleum, such as gasoline or diesel fuel; solvents, such as perchlorethylene; heavy metals, such as lead or arsenic, or myriad other environmental contaminants.
What are the steps in the Phase 2 Process?
A Phase 2 Environmental Site Assessment is usually triggered when evidence of such contamination is observed or collected during a Phase 1 Environmental Site Assessment. In order to determine whether a property is safe for an intended use, soil, groundwater, or soil vapor samples are collected, analyzed by an accredited laboratory, and compared to published government screening levels or risk-based concentrations for the contaminants of concern.
The final cleanup level for various contaminants at a site are often based upon the current or intended future use of the site. For example, the level of contaminants considered to be protective of human health and the environment at a commercial or industrial property are usually higher than the cleanup standards established for a school, residence, or playground.
A conceptual site model (CSM) is often developed for a site in order to to integrate all site features and to determine whether data gaps exist, requiring additional sampling. The CSM also informs the selection of the best remedial actions for a given location, suite of contaminants, and exposure pathways.
Once enough data is collected and analyzed to provide a statistically defensible course of action, the third phase, known as a remedial action, can proceed. The remediation may include removing contaminated soil; pumping and treating contaminated groundwater or soil vapor; or the establishment of institutional or engineering controls to prevent human exposure, such as a soil cap or a sub-slab depressurization system.
At AAI, we strive to provide the most scientifically sound, economical, and time-tested remedial strategies to quickly get your property or development project back on track for whatever your final intended use may be.
AAI serves all of Oregon and Washington, including Portland, Salem, Gresham, Medford, Roseburg, Eugene, Corvallis, Bend, Klamath Falls, the Oregon Coast, the Columbia Gorge, Pendleton, La Grande, Vancouver, Olympia, Tacoma, Seattle, Spokane, and Tri Cities.