Dealing with waste from cannabis cultivation/production processes is addressed by the Federal Cannabis Act.
This fact sheet from the Provincial Ministry of Justice and Solicitor General summarizes how waste from these facilities is managed.
Liquid and solid wastes must be 50% mixed in with non-cannabis related products/materials so that it becomes unusable.
For solid cannabis products, if the product is 50% mixed in with compostable material such as yard waste, food waste, wood chips grease or other compostable oil products or other wastes approved by Alberta Parks and Environment, the waste must be sent to an authorized class I or II composting facility or anaerobic digester for processing. If the product is mixed in with non-compostable material, such as cat litter, plastic and saw dust, it must be sent to an authorized class I or II landfill.