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Biosolids Compost

King County contracts with a local private company (GroCo, Inc.) to make a biosolids compost which is marketed in the Greater Seattle area as GroCo.

Three parts sawdust and one part biosolids are blended and composted to create a fine-textured, Class A biosolids product. Biosolids compost improves soils and provides plant nutrients.

GroCo compost information sheet (pdf)

gardening with GroCo compost

Landscaping
GroCo compost has many uses, on golf courses and parks, in home and school gardens and to enhance highway medians. Biosolids compost can be used as a soil conditioner and as a mulch around plantings. By increasing soil aeration, compacted soils are made more porous. Sandy soils benefit from the addition of organic matter which improves water retention.

Gardening
Biosolids compost improves soil characteristics and encourages vigorous plant growth in both planting beds and flower pots.

Community Involvement
GroCo is used in numerous community beautification projects, such as landscaping (before and after photos below) at Seattle's Eckstein Middle School.

Eckstein M.S. landscaping Eckstein M.S.

 

GroCo in the GreenwayCompost "Regreening Program"

GroCo compost has been used in an innovative project to rehabilitate logging roads and help stabilize mountain slopes by enhancing the growth of native vegetation in the Mountains to Sound Greenway.

  

GroCo Compost Quality

GroCo is available throughout the greater Seattle area.
For information: 206-622-5141

Return to Biosolids Home


For questions about biosolids recycling or this website, please use 'comments' link below or contact:

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

Updated: April 18, 2008



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