The deep dig on soil testing - FAQ

How we're testing soil after ash and debris cleanup to ensure your property is safe to rebuild on.


Soil testing is a vital part of the cleanup process, and the last thing we do after we've cleared all the ash and debris from your property. Protecting your health and safety, and ensuring your property is ready for rebuilding, is our top priority.


Quick summary

Burned ash and debris may include hazardous contaminants, and those contaminants can get in to the soil below. So we're taking soil samples from each property and assessing them for those contaminants. As long as the samples are below certain levels (called "screening levels;" more on those in the FAQ) then your soil is considered safe and ready for rebuilding.


We'll mail and email you an official letter verifying your soil is safe, plus the results of your property's soil assessment, for your records.


That's a simple overview of process and science, however. See our FAQ below for a complete breakdown of how we assess your soil. If you still have questions, contact the cleanup hotline: 503-934-1700 or odot.wildfire@odot.state.or.us.


Soil testing FAQ


What contaminants are you testing for?

We're looking for the amounts of eight heavy metals in your soil: arsenic, barium, cadmium, chromium, lead, mercury, selenium and silver.


Why are you testing for these eight metals?

These eight metals are toxic heavy metals the U.S. Environmental Protection Agency lists and monitors under the Resource Recovery and Conservation Act. These metals can be toxic even in small concentrations, which is why the Oregon Department of Environmental Quality’s screening criteria are so low.


Testing for these metals serves as a surrogate for other potentially harmful contaminants. This same methodology has been used in California for soil testing.


I’m concerned about there being any amount of these metals on my property. Is it safe for them to be there?

All of these metals are also naturally occurring in the environment. Levels that are naturally present in Oregon soils are called background levels. The screening level is the amount below which there is no harm to human health.


Where did you take samples on the property?

State contractors took soil samples in the footprints of any structure that was burned and where ash and debris has been cleared. The multiple samples in the table attached to the soil sample document we sent you are from the different locations around the property.


Do I need to submit my soil test in order to rebuild?

No. Counties will not be asking for soil tests as part of rebuilding. However, the state recommends that you keep a copy of this paperwork for your records.


If I’m interested in selling my property, are my soil test results...

Short answer

No, it is not the same as environmental due diligence, an environmental site assessment, or a no further action letter. Those are based on cleanup work that includes the entire site and all possible sources of contamination. The state-led cleanup process included soil sampling in building footprints and analyzed those samples for eight specific metals.


Whether or not the documentation is adequate for any environmental due diligence that a financial institution would require in selling your property is up to that financial institution.


Long answer

This is not the same as doing environmental due diligence through a Phase I or Phase II Environmental Site Assessment. Those are very specific analyses that take a look at an entire property. Under the state-led cleanup process, state contractors only collected soil samples in building footprints in anticipation of where buildings would be rebuilt and people would spend the most time. Additionally, the state tested for contaminants associated with the wildfires, but this testing did not include everything that may be required under an environmental site assessment.


This is not the same as a No Further Action determination (documented in the form of a letter). The Oregon Department of Environmental Quality issues a No Further Action determination once a site has gone through a complete cleanup process:

  • Site characterization to determine what type and how much contamination is present.

  • Risk assessment to understand exposure pathways.

  • Feasibility study to determine potential cleanup options.

  • Selection of a cleanup plan.

  • Implementation of the cleanup plan.

  • Establish any maintenance and monitoring required.

I live at a mobile home park and didn’t get soil testing results, how can I get those?

The Oregon Debris Management Task Force provided a complete summary of soil testing results for a whole mobile home park to the park owner if they are also the property owner. You can request/find those results by contacting the property owner.


If you live in a mobile home park and own the property, when cleanup is completed, you will receive a letter from the state that includes the soil testing results.


Wildfire waste and debris removal

The State of Oregon is working with federal, state and local partners to remove hazardous waste, and ash and debris from the 2020 Oregon wildfires safely, efficiently, and as quickly as possible. The Oregon Departments of Transportation, Environmental Quality and Emergency Management are leading the effort, with U.S. Environmental Protection Agency assistance.