Some regulations are site-specific
The design and location of your intended project can significantly influence the viability of your marijuana growing or processing operation. For example, marijuana growing is prohibited in some areas of the state due to local ordinances or federal policy.
The need for permits and authorizations for a project depend on zoning rules, location, and operation details. You might want to ask what approvals are needed through your county or city permitting offices.
State Environmental Policy Act
Check with your local permitting agency (e.g., building department) first. A pre-approval meeting with the local permitting agency will help determine whether to complete an environmental checklist (SEPA). If a SEPA review is required, complete a checklist describing the project’s environmental impacts. (This can include processes such as wastewater and solid waste disposal, use of CO2 in growing, or odor controls.)
Because the production and processing of marijuana can impact air quality, produce odorous emissions, and cause off-site nuisance impacts due to odor, processors and producers are subject to air quality requirements. Contact the appropriate Clean Air Agency for more information.
If you are connected to a sewer system, you might be able to discharge wastewater to your sewer but some pre-treatment might be necessary. You can contact your regional Ecology office or local jurisdiction to be sure.
If you are not connected to a sewer, you can seek information from us to determine whether you need a water quality permit. Our wastewater discharge checklist describes discharge options for marijuana producers and processors, and requests information that will allow us to evaluate whether you need a water quality permit.
Water availability for new permitted uses varies significantly from place to place. You might need a water right permit if you intend to use surface water or groundwater in excess of 5,000 gallons per day. Because of the difficulty in obtaining a new water right, industrial greenhouses and outdoor growers might want to consider connecting to an existing water purveyor or irrigation district, where available.
If you will need less than 5,000 gallons of water per day, your use may qualify under the groundwater permit exemption. There might be local rules or requirements related to a new permit-exempt well, depending on the watershed. Please contact your local county for more information about whether water is legally available for use at your location if you are not on a municipal water supply.
The U.S. Bureau of Reclamation issued a policy statement prohibiting the use of federal water or facilities for the cultivation of marijuana. Questions on the policy should be directed to the Bureau.
If you generate any dangerous wastes, you'll need to manage your waste properly. Dangerous wastes might include:
- Any processed, concentrated marijuana waste with 10 percent THC (tetrahydrocannabinol) or greater would designate as a state-only dangerous waste (WT02)
- Fluorescent bulbs or other bulbs with mercury
- Unused pesticides, herbicides, etc. to be disposed
- Waste solvents
- Used batteries
Waste generated from processing cannabis must be designated to determine if it is dangerous waste. Process wastes contaminated with the solvents allowed by the Liquor and Cannabis Board for extraction would not designate as dangerous waste under normal conditions because they are not:
- A liquid with a flash point less than 140 degrees F (WAC 173-303-090(5)(i)); and
- Not a solid which may ignite through friction, absorption of moisture, or spontaneous chemical change; and
- Listed dangerous waste, listed solvents (WAC 173-303-9904; waste codes F001 – F005).
Solid waste management is regulated at the local level by county health departments. You should consult with your local health department to determine what steps you must take to best manage your solid waste.