Washington – Composting Rules

The state of Washington has comprehensive composting regulations to facilitate composting. The regulations conditionally exempt several types of composting facilities – including those that process limited amounts of food scraps – from the requirement to obtain a permit. Indeed, the Washington Department of Ecology recognizes the many benefits of using compost to bolster soil health, and much of the most common agricultural composting is exempt from facility permitting.

Previous state regulations went into effect on February 10, 2003; however, the solid waste rules were revised in 2013 to include exemptions that reflect the state’s commitment to more efficient composting options, and a new section addressing solid waste permitting for anaerobic digesters. In 2018, the rules were further revised to clarify and refine their applicability to on-farm compost use.

 

Composting Facility Permit Exemptions

The state of Washington updated the 2003 language of its solid waste handling regulations in 2013, removing the former hierarchy of feedstock types, with the state instead describing organic materials as pre- and post-consumer wastes, comprised of either food, animal, or vegetative-based sources. Permitting exemptions are based on the specific site’s feedstock materials, volume of materials on-site, and whether the finished materials are used on-site or distributed off-site.

To qualify for an exemption to obtaining a solid waste handling permit, an operation must meet conditions stipulated in Table 220-A of WAC 173-350-220. An abbreviated version of Table 220-A is shown below.

Organic Materials

Volume

Requirements for Compost Facility

(1)

All organic feedstocks

Max of 25 cubic yards (5,000 gallons) of material on-site at any one time No notification, reporting, or testing requirements

(2)

All organic feedstocks

Greater than 25 but no more than 250 cubic yards of material on-site at any one time

Not exceeding 1,000 cubic yards in a calendar year

(a) Submit notification of intent to operate as a conditionally exempt facility 30 days prior to operation

(b) If distributing composted material off-site, must: (i) Manage the operation to reduce pathogens to meet limits set by Table 220-B;

(ii) Conduct compost analysis according to the requirements of Table 220-B. Testing frequency is based on volume of compost produced annually as required by subsection (4)(a)(x)(B) of 173-350-220; and

(iii) Submit annual reports and results of composted material analysis to the department and the jurisdictional health department by April 1st of each year

 

(3)
Yard debris
 
Crop residues
 
Manure and bedding
 
Bulking agents
Greater than 25 but no more than 250 cubic yards of material on-site at any one time

Not exceeding 2,500 cubic yards in a calendar year

(a) Submit notification of intent to operate as a conditionally exempt facility 30 days prior to operation

(b) If distributing composted material off-site, must: (i) Manage the operation to reduce pathogens to meet limits set by Table 220-B;

(ii) Conduct compost analysis according to the requirements of Table 220-B. Testing frequency is based on volume of compost produced annually as required by subsection (4)(a)(x)(B) of 173-350-220; and

(iii) Submit annual reports and results of composted material analysis to the department and the jurisdictional health department by April 1st of each year

 

(4)
Agricultural wastes
 
Yard debris
 
Bulking agents
Greater than 25 but no more than 1,000 cubic yards of agricultural wastes and bulking agents on-farm at any one time

Up to 50% of organic materials on-farm can be yard debris

If managing more than 25 cubic yards of imported yard debris on-site or composting only agricultural wastes but distributing off-site, then the operation must:

(a) Submit notification of intent to operate as a conditionally exempt facility 30 days prior to operation

(b) If only managing agricultural waste and not distributing compost off-farm, then (a) is not required

(c) Operations distributing compost off-site required to: (i) Manage the operation to reduce pathogens to meet limits set by Table 220-B;

(ii) Conduct compost analysis according to the requirements of Table 220-B. Testing frequency is based on volume of compost produced annually as required by subsection (4)(a)(x)(B) of 173-350-220; and

(iii) Submit annual reports and results of composted material analysis to the department and the jurisdictional health department by April 1st of each year

 

(5)
Agricultural wastes
 
Manure and bedding from zoos
 
Bulking agents
Greater than 25 cubic yards with no upper limits when only agricultural wastes, manure and bedding from zoos

Bulking agents are processed on-farm (or on-site for zoos)

Agricultural farms that distribute composted material off-farm (or off-site for zoos):

(a) Submit notification of intent to operate as a conditionally exempt facility 30 days prior to operation

(b) Composting at a diary must be part of an updated dairy nutrient management plan as required by chapter 90.64 RCW (Dairy Nutrient Management Act)

(c) Composting on non-dairy farms must be part of an updated farm management plan written in conjunction with a conservation district, a qualified engineer, or other agricultural professional able to certify that the plan meets applicable conservation practice standards in the USDA Washington Field Office Technical Guide, Code 317

(d) Operations distributing compost off-site required to: (i) Manage the operation to reduce pathogens to meet limits set by Table 220-B;

(ii) Conduct compost analysis according to the requirements of Table 220-B. Testing frequency is based on volume of compost produced annually as required by subsection (4)(a)(x)(B) of 173-350-220; and

(iii) Submit annual reports and results of composted material analysis to the department and the jurisdictional health department by April 1st of each year

 

 

Performance Standards

Regardless of exemption from obtaining a permit, all compost facilities in the state of Washington must adhere to specific performance standards, which are designed to prevent public nuisance and negative environmental or public health consequences. These performance and site requirements seek to prevent the handling of wastes in a manner that could pose hazards to water and air quality if organic materials were mismanaged. Found in WAC 173-350-040, they are:

Performance Standards.

The owner or operator of all solid waste facilities subject to this chapter shall:

(1) Design, construct, operate, and close all facilities in a manner that does not pose a threat to human health or the environment;

(2) Comply with chapter 90.48 RCW, Water pollution control and implementing regulations, including chapter 173-200 WAC, Water quality standards for groundwaters of the state of Washington;

(3) Conform to the approved local comprehensive solid waste management plan prepared in accordance with chapter 70.95 RCW, Solid waste management—Reduction and recycling, and/or the local hazardous waste management plan prepared in accordance with chapter 70.105 RCW, Hazardous waste management;

(4) Not cause any violation of emission standards or ambient air quality standards at the property boundary of any facility and comply with chapter 70.94 RCW, Washington Clean Air Act; and

(5) Comply with all other applicable local, state, and federal laws and regulations.

 

More Information

—————————————
Original post from July 30, 2012
Updated July 28, 2021

Avatar photo
Follow Brenda Platt:
Brenda Platt

Brenda Platt directs ILSR's Composting for Community project.