Commercial Fertilizer – A substance containing one or more recognized plant nutrients that is designated for use or claimed to have value in promoting plant growth. Commercial fertilizers (including liming agents and micronutrient fertilizers) are fully regulated under the Fertilizer Regulation Act.

Hazardous Waste – Wastes designated by the U.S. EPA as hazardous under federal regulations (40 CFR 261) and those designated by the State of Washington as "dangerous" and regulated by the Dangerous Waste Regulations (chapter 173-303 WAC).

Lime or Liming Agent – A product with calcium or magnesium as the principal constituent which is intended to neutralize soil acidity. Liming agents are a commercial fertilizer by definition in the Fertilizer Regulation Act and if waste-derived, they are subject to review under Ecology’s fertilizer review process.

Micronutrient Fertilizer – A produced or imported commercial fertilizer that contains commercially valuable concentrations of micronutrients (boron, chlorine, cobalt, copper, iron, manganese, molybdenum, sodium, and zinc), but does not contain commercially valuable concentrations of nitrogen, phosphoric acid, available phosphorus, potash, calcium, magnesium, or sulfur.

Soil Amendment – A material that is added to the soil for the purpose of improving the physical and biological characteristics of the soil including improving the tilth, porosity, aeration, aggregation, water holding potential, or to increase the organic content, ion exchange capacity and microbial viability. Soil amendments do not include commercial fertilizers, liming agents, or composted materials.

Solid Waste – Putrescible and nonputrescible solid and semisolid wastes including garbage, ashes, industrial wastes, and sewage sludge.

Waste-derived Fertilizer – A commercial fertilizer that is derived in whole or in part from solid waste as defined in chapter 70.95 RCW (Solid Waste law) or chapter 70.105 RCW (Hazardous Waste law) or rules adopted under those laws.