Step 1

Place 2 ft (60 cm) layer of co-compost material on the ground.  Ensure that the base is packed tightly and large enough to allow for a 2 ft (60 cm) clearance around the carcass. The 2 ft (60 cm) base acts as a sponge to absorb fluids. Take into consideration that the base layer will compact when the carcass is placed on top.

Step 2

Lay the carcass in the centre of the base on its back or side, again, ensuring that there is a 2 ft (60 cm) clearance of co-compost around the carcass.

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Step 3

For ruminants larger than 300 lbs (136 kg), it is recommended to cut open the thoracic, abdominal cavities, viscera, as well as, slice large muscle mass to accelerate the compost process and prevent possible explosion of the intestinal cavities.  For non-ruminant animals, no lacerations are required. Before the animal is covered, wet the animal hair or fur with water, this provides good carcass to co-compost contact.

Step 4

Cover the entire carcass with at least 2 ft (60 cm) of material (straw).  The 2 ft layer of material will act as a biofilter to reduce unwanted odours.

Step 5

Once the composting pile is set up you are in the Primary Stage.  In this stage, the temperature should increase to 40-65°C. Once the temperature stays above 40°C for seven consecutive days and then drops, the pile is ready to be turned (approximately 3 months in ideal weather conditions). By this time the compost pile should contain bones and minimal flesh.

Step 6

Once the pile is turned you are in the Secondary Stage. The secondary composting period is usually equal to the primary composting time (approximately 3 more months). Monitor the pile daily, the composting process is usually finished after the temperature greater than 55°C for seven consecutive days drops.  Check the pile, if there are no signs of flesh and only brittle bones left, the composting is done and can be applied on-farm.  If there are still signs of flesh, turn the pile again and check the pile in a couple of months for flesh.  Remember, composting is complete when all of the flesh has disappeared.

Note:  For static composting mortalities are stacked, whereas for windrow composting mortalities are arranged in a row (see diagrams below).

Static Composting

Windrow Composting