Department of
Environmental Quality

Wood or mill yard debris facilities manage exclusively solid wood, bark or wood fiber generated from wood products manufacturing.

Under Idaho's Solid Waste Management Rules, wood or mill yard debris facilities that manage their debris according the procedures outlined in the Wood and Mill Yard Debris Technical Guidance Manual are exempt from state rules. Those facilities that do not comply with this manual are automatically regulated under Tier I regulations unless DEQ determines, based on site-specific criteria, that more stringent regulations are applicable.

Wood and Mill Yard Debris Technical Guidance Manual

The Wood and Mill Yard Debris Technical Guidance Manual outlines various methods for the use and disposal of accumulated wood and mill yard debris generated within wood and mill yards during the process of manufacturing wood products. Such debris consists of wood fiber materials with components of soil, rock, and moisture. The manual also addresses blending of boiler ash with wood debris for management and disposal.

Wood Debris Minimization

Typical debris production is 100 to 700 cubic yards per million board feet of logs processed. Historically, this material was landfilled near the producing yard, filling low areas and small draws. The Technical Guidance Manual offers various methods to minimize the accumulation of wood debris including surfacing log yards with an all-weather surface such as asphalt, sorting and scaling logs in a centralized location, and cleaning and marketing debris as fuel.

Best Management Practices for Wood Storage

Wood and mill yard debris management practices for the storage of debris are critical to mill operations and protecting the environment. The manual offers guidance on storing wood to minimize fire potential, prevent generation of leachate into ground water, and avoid runoff of pollutants from stockpiles.

Boiler Ash Management

Most facilities that produce wood debris also produce boiler ash from their steam plant. Many studies have addressed the impacts of adding boiler ash to wood debris, both for land application and disposal. Boiler ash is residue from wood-fired boilers. To prevent adverse environmental impacts, the manual recommends limiting boiler ash to 2% by volume for land application and to 6% by volume for disposal.

Alternative Uses of Wood and Mill Yard Debris

The Technical Guidance Manual provides information and offers examples of the following alternative uses of wood and mill yard debris:

• Firewood
• Hog fuel
• Landfill alternative daily cover and final cover material
• Land reclamation and erosion control
• Landscaping materials
• Road Fill
• Soil amendments
• Stockyard bedding
• Visual and sound barriers
• Wood and mill yard debris landfill

Tier I Solid Waste Facility Regulations

Under Idaho's Solid Waste Management Rules, Tier I facilities are required to demonstrate compliance with several requirements, including appropriate signage, nuisance (disease, vector, odor, and litter) control, secure access, open burning restrictions, and stormwater runoff controls. The rules also impose certain notification and documentation requirements.