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Biosolids Compost Regreening Program

The Mountains to Sound Greenway Trust is a public-private partnership of citizens, private landowners, public agencies and local governments working together to protect and enhance the green landscapes along Interstate 90, connecting Puget Sound with the Cascade Mountains.

The Compost Regreening Program, coordinated by the Trust, involves local and international youth groups and other volunteers to revegetate harvested mountain slopes and unsightly, erosion-prone road scars.

Heavy equipment is used to restore the natural slopes and drainages. Biosolids compost is then blended into the soil surface.

At right is an example of log terraces used to hold the recontoured slope in place. Grass seed is mixed into the compost and straw may be layered on top to help stabilize soils.

retaining terraces
new growth
Grass establishes quickly, preventing erosion by rain and snow during the following months. Volunteers will return the next season to plant tree seedlings.
The restored roadway, visible as a green "x" in the lower left of this picture, contrasts with an un-restored road on the slope above.

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For questions about biosolids recycling or this website, please contact us at:

Resource Recovery
201 S. Jackson Street
Mail Stop: KSC-NR-0512
Seattle, WA 98104
Phone: (206) 684-1255
Fax: (206) 684-2057

Updated: May 30, 2008


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