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Home / News / Newsfeed / Treated Wood Waste

Treated Wood Waste

January 1, 2021
wooden utility pole with cables running in all directions

[Update: As of August 31, 2021, Assembly Bill No. 332, Chapter 147, related to the Health and Safety Code concerning hazardous waste, has added and repealed Article 11.2 (commencing with Section 25230) of Chapter 6.5 of Division 20. Article 11.2 addresses the unique circumstances associated with the generation and management of treated wood waste. For more information, please visit CA legislature’s website here.]


Wood treated with chemical preservatives for protection against pests and environmental conditions is called “treated wood.” Treated wood is used for fence posts, railroad ties, utility poles, landscape timbers, pilings, docks, piers, guardrails, and decking. Wood treatment chemicals include arsenic, chromium, copper, pentachlorophenol, and creosote. These chemicals can cause wood waste to become hazardous waste in California.

In 1995, legislation was passed that exempted most treated wood waste (TWW) from being managed as hazardous waste. TWW – such as poles, crossarms, pilings, fence posts, lumber, support timbers, flume lumber, and cooling tower lumber, from electric, gas, or telephone service companies – could be deposited in a municipal solid waste landfill that has a composite liner. In 2007, the State adopted alternative management standards for TWW that applied to all generators [Health and Safety Code (HSC) Section 25150.7, regulations codified at 22 CCR Section 67386, et seq.]. This allowed TWW from all generators to be managed by alternative standards rather than as hazardous waste, provided the waste was not a Resource Conservation and Recovery Act (RCRA) hazardous waste or designated to be burned. However, this exemption had a sunset date of December 31, 2020.

To address the exemption sunset date, Senate Bill (SB) 68 was written and passed by the State legislature in 2020 to permanently extend the alternative management standards for TWW. However, Governor Newsom did not sign the bill, citing budget considerations.

Therefore, if you generate TWW and are not an electric, gas, or telephone utility, after January 1, 2021, you must manage TWW that meets California criteria for a hazardous waste as a fully regulated hazardous waste. This means TWW must not be placed directly on the ground, cannot be accumulated for more than 90 days for a Large Quantity Generator (LQG) or 180 days for a Small Quantity Generator (SQG), and is subject to container labeling and hazardous waste manifest rules. TWW will now count toward your generator status and may cause you to become an LQG.

The California Department of Toxic Substances Control (DTSC) has indicated that they intend to issue a temporary variance that would allow the current management methods to continue, until such time as the State legislature can act on the matter again, e.g., by submitting a revised bill to the Governor. When available, the variance and related forms and procedures will be posted to the DTSC’s TWW webpage, located here: https://dtsc.ca.gov/toxics-in-products/treated-wood-waste.


Yorke Engineering has assisted over 1,800 industrial and government facilities with air, waste, and water regulatory compliance and permitting throughout California. Our staff are very experienced and specialized in assisting customers with their specific EH&S needs related to the local air districts, CARB, DTSC, Water Boards, CUPAs, U.S. EPA, and other regulatory agencies. Learn more about how we can help you here: Waste | Yorke Engineering, LLC (yorkeengr.com).

Main Office:

31726 Rancho Viejo Rd. Suite 218
San Juan Capistrano, CA 92675

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