About Us

Regulatory Agency Partnering

2004 Commercial Composting Regulatory Update

Effective December 21, 2003 in King County and February 11, 2004 Statewide - Minimal Functional Standards for Composting Facilities Regulated by the Washington State Department of Ecology WAC 173-350-220 will go into effect Standardizing:
  • Product Testing
  • Compost Facility Location
  • Compost Facility Design
  • Operating Procedures
According to WAC 173-350-220 "Composting means the biological degradation and transformation of organic solid waste under controlled conditions designed to promote aerobic decomposition."

Cedar Grove Composting has met all previous standards in the past, meets todays required standards and will continue to meet the regulated standards of the future. The new standards replace The Interim Guidelines for Grade AA Compost Quality established by the WA State Department of Ecology. No commercial composting facility can lawfully continue to operate and market a bona fide compost product unless the new guidelines are being followed.

All compost products sold in 2004 must pass the NEW Washington State's Regulated Testing parameters for analyzing composted material. They include: heavy metals, nitrogen content, sharps and inerts, pH level, stability, e. coli or salmonella. In addition, Cedar Grove chooses to tests for: nutrient content, trace elements, C/N ratio, moisture holding capacity, conductivity, pesticide and herbicides residue, weed seeds and seed germination.

At Cedar Grove we consistently test in our on-site lab and greenhouse:
  • All incoming feedstock from the secondary process and screening prior to curing
  • Bi-weekly bioassay samples of the current sales pile is tested for growth and weeds
  • Weekly lab tests on sales pile for pH, ammonia, salts, and nitrate
  • Weekly walk-through the plant, by environmental coordinator and marketing team, visually inspecting product moisture, odor, porosity and temperature
In addition, to meet regulatory standards we send samples to outside laboratories every 10,000 yards of incoming feedstock. No product is sold without passing our internal standards and the newly required testing parameters.

Cedar Grove Composting's operations follow and comply with the regulatory requirements and permit conditions outlined and attached to this Plan. Cedar Grove Composting is regulated by the following agencies:
  • Seattle-King County Department of Public Health
  • Puget Sound Clean Air Agency
  • King County Department of Metropolitan Services, Industrial Waste Division
  • Washington Department of Ecology
Cedar Grove Composting is committed to a goal of regulatory compliance through ISO 14001 continuous improvement. It will diligently work toward implementation of a permit that combines applicable regulatory requirements and sets performance-based standards for the facility and the composting industry.

The facility uses the following as regulatory guidelines:
  • Washington Department of Ecology Compost Facility Resource Handbook
  • Compost Council's Facility Operating Guide
  • ISO 14001 Technical Peer Review
We welcome your questions and invite you to e-mail us at info@cedar-grove.com or call us for more information toll free at
1-877-764-5748.
© 2008 Cedar Grove Composting
Cedar Grove