Treatment activities at many wood preserving sites and lumber mills have left behind widespread soil, surface water and groundwater contamination. ERF has begun addressing this issue in Northern California by targeting sites owned by three major lumber companies.

Sierra Pacific Industries
Eel River Sawmills, Inc
Pacific Lumber

Toxicity Concerns in the Lumber Industry
The most toxic process during lumber milling is wood preservation. There are two general forms of wood preservation used by the lumber industry:

1.Surface Treatment of lumber is commonly used to provide short-term cosmetic protection against mold and sap stains. Surface treatment chemicals are often applied by using dip tanks and spraying operations. 

Both treatment methods are highly toxic and leave behind soil, surface water and groundwater contamination. The highly toxic chlorophenolic compounds, Pentachlorophenol (“PCP”) and Tetrachlorophenol (“TCP”), were widely used for both surface treatment and wood treatment from the 1950's until their use was restricted in the 1980's.   PCP, a known carcinogen, also contains extremely toxic dioxin and furan impurities and hexachlorobenzene.  Dioxins are considered by many to be the most potent carcinogenic chemicals known and, even in very small quantities, may disrupt the functioning of the human endocrine system.

Chromated Copper Arsenate (CCA) is a  wood preservative mixture consisting of three compounds (arsenic, chromium, and copper). It too is widely used for both surface treatment and wood treatment. The main contaminants of concern from CCA use at mills are arsenic and hexavalent chromium. 

Exposures to contaminated surface soil and groundwater is a particular concern to on-site workers and to neighboring communities.  Surface water contamination may have devastating impacts on the local environment. The effects of these biologically persistent chemicals will magnify as they move up the food chain.

Other Contaminants at Lumber Mills
There is a large array of chemicals used at industrial lumber mills.  Poor housekeeping and disposal practices frequently leads to soil and water contamination at these sites. For example, hydraulic fluids, oils and diesel fuels are used for heavy machinery such as forklifts, cranes and loaders. Hydraulic fluids may also be used on sawmill equipment. Petrochemical lubricants are often applied to chain driven machines, including sorters, “green chains” and lumber banders. Truck shops and truck wash facilities at mills may be sources of petrochemical and other contaminants such as waste oils and solvents and transmission fluids. In addition, when storm water contacts large quantities of woody debris, such as bark and sawdust, the chemical composition of the water may be drastically changed. Storm water discharges from lumber mills may have very low pH, and high levels of tannins, lignins and suspended solids, all of which may be toxic to fish and wildlife.