Compost

wood based compost

STEP are currently undertaking research into the quality of compost for use in LID installations.

Compost shall be stable, humus-like material produced from the aerobic decomposition of organic feedstocks, composted and cured until maturity. Compost shall be produced under the Compost Council of Canada’s Compost Quality Alliance (CQA) certification program through testing by an OMAFRA accredited soil laboratory, and certified as category ‘AA’ under Ontario Compost Quality Standards.

Specifications for category 'AA' product under Ontario Compost Quality Standards

Parameter	Acceptable range
pH	5.5 - 8.5
Soluble Salts (EC)	< 4 mS/cm
Moisture Content	< 50% by weight
Organic matter	> 30% by dry weight
C/N ratio	12 to 22
Pathogens	See: MOECC 2012
Maturity	See: MOECC 2012
Particle size	100% < 12.7 mm (1/2”)
Foreign Material	< 1.0% by dry weight > 3 mm < 0.5% plastic by dry weight no foreign matter > 25 mm per 500 mL no sharp foreign matter that could cause harm to humans or animals.
Arsenic	≤ 13 mg/kg dry weight
Cadmium	≤ 3 mg/kg dry weight
Chromium	≤ 210 mg/kg dry weight
Cobalt	≤ 34 mg/kg dry weight
Copper	≤ 100 mg/kg dry weight
Lead	≤ 150 mg/kg dry weight
Mercury	≤ 0.8 mg/kg dry weight
Molybdenum	≤ 5 mg/kg dry weight
Nickel	≤ 62 mg/kg dry weight
Selenium	≤ 2 mg/kg dry weight
Sodium, Percent Saturation	< 2%
Zinc	≤ 500 mg/kg dry weight

Decayed organic material used as a plant fertilizer. Compost helps to support healthy plant growth through the slow release of nutrients and the retention of moisture in the soil.

Sustainable Technologies Evaluation Program

Low Impact Development. A stormwater management strategy that seeks to mitigate the impacts of increased urban runoff and stormwater pollution by managing it as close to its source as possible. It comprises a set of site design approaches and small scale stormwater management practices that promote the use of natural systems for infiltration and evapotranspiration, and rainwater harvesting.

Decayed organic material used as a plant fertilizer. Compost helps to support healthy plant growth through the slow release of nutrients and the retention of moisture in the soil.