Compost

Compost shall be stable, humus-like material produced from the aerobic decomposition of organic feedstocks, composted and cured until maturity. Compost shall be certified to comply with mandatory Ontario Compost Quality Standards for Category ‘AA’ or ‘A’ Compost for concentrations of the 11 regulated metals, pathogens, foreign matter, maturity and labelling (OMOECC 2012) and Canadian Food and Inspection Agency (CFIA) regulations T-4-93 (CFIA 1997a) and T-4-120 (CFIA 1997b).

Compost shall also be certified to meet quality parameters recommended under the Compost Council of Canada’s Compost Quality Alliance (CQA) certification program (A&L Canada Laboratories 2004) through testing by an accredited soil laboratory (OMAFRA 2016):

Specifications

Parameter	Acceptable range
pH	5.5 - 8.5
Soluble Salts (EC)	< 5 mS/cm
Moisture Content	< 50% by weight
Organic matter	> 30% by dry weight
C/N ratio	12 to 22
Pathogens	OMOECC 2012
Maturity	OMOECC 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	≤ 20 mg/kg dry weight
Chromium	≤ 210 mg/kg dry weight</td
Cobalt	≤ 34 mg/kg dry weight
Copper	≤ 400 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	≤ 700 mg/kg dry weight

Where the custom calculated depth of compost amendment exceeds 7 centimetres (cm), or concentrations of any of the 11 regulated metals are near the maximum allowable limit, use Appendix 7 of Ontario Compost Quality Standards (OMOECC 2012) to determine the maximum application rate that will not exceed CFIA regulations for metals loading over a 45 year time period (CFIA 1997a).

The Contractor shall submit to the Owner’s Representative a 4L sample, with laboratory testing results or quality assurance documentation certifying that the material or product meets the requirements.

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.

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.

The total mass of a pollutant entering a waterbody over a defined time period.

The net amount of something (e.g. chemical, such as phosphorus), calculated as the product of concentration and volume in a given time. Some BMPs significantly reduce loading of pollutants to the environment by reducing volume more so than concentration.