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Toxics Cleanup Program



Tacoma Smelter Plume

Sampling in the Yard Program

Determining the size of the property and creating a map.
Determining the size of the property and creating a map.


Photo: Collecting samples by pushing a tube into the ground.
Collecting samples by pushing a tube into the ground.

Photo: Placing samples into one container to make a composite sample.
Placing samples into one container to make a composite sample.   

Photos courtesy of Kennedy Jenks and GeoSyntec.

Ecology is offering free soil sampling to thousands of properties within the Yard Program service area, working neighborhood by neighborhood.

How do I sign up for soil sampling?

To find out which program you are eligible for…

  1. Visit our interactive map of the Tacoma Smelter Plume.
  2. Search for your address.
  3. Click on the red diamond to get the program information for your neighborhood.
  4. To find out about soil sampling outside of the Yard Program Service Area, check out our Soil Sampling page.
  5. If your property is in the Yard Program Service Area, it is possible that your property has already been sampled. To find out if there is existing soil sampling data for your property go to our public database.
  6. If your property is within the Yard Program Service Area and we do not have existing soil sampling data for your property, please sign up for soil sampling.  We do not offer soil sampling inside the Study Area.

How does sampling work? 

After you sign up, if you have circled “schedule an appointment,” we will contact you to make an appointment. The sampling process takes about an hour, but we do not require that you be home. During the appointment, we will:

  1. Determine the size of the property and create a map.
  2. Divide the property into 1-4 “units.”
  3. Ask questions to identify the areas you use the most-“high use areas."  These may include a play area, lawn, or garden bed.
  4. Take 8 sub samples from the top six inches from each unit.
  5. Combine these 8 samples into one jar to make a composite sample.
  6. Take the samples from your property to a lab.

To learn more about soil sampling, read our soil sampling fact sheet.

Sampling Results

We will send the results to you in the mail within one to two months and post them on the Arsenic in Soil Database.

We will offer cleanup for yards with arsenic over 100 parts per million (ppm). Ecology offers soil replacement for yards with arsenic above 100 ppm or lead above 500 ppm.  For more information about this action level, please see our fact sheet.  Soil replacement involves removal of the contaminated soil, replacement with new soil and landscape restoration.  Please visit our Cleanup Process webpage to learn more about the cleanup process or read the soil removal and replacement fact sheet.

Many yards will not qualify for soil replacement but will have arsenic over the state cleanup level of 20 ppm.   Ecology and local health departments are working to educate homeowners about reducing exposure to contaminated soils. We recommend homeowners fix bare patches in their lawn and cover bare soils. We also recommend growing vegetables in raised beds. For more information, visit our webpage on landscaping and gardening in arsenic and lead contaminated soils. 

Ecology does not recommend removing soils from your own yard, unless it is part of a landscaping or building project. For more information about removing soils, please visit the Technical Assistance webpage or contact Eva Barber at (360) 407-7094 or Eva.Barber@ecy.wa.gov.

This page last updated July 2017