Wood preservation facilities, creosote: chapter D-9

9. Waste, Process Emissions and Disposal

For general information on process emissions and disposal, consult Section 9 of Part I, Chapter A - General Recommendations for All Wood Preservatives.

9.1 Control, Treatment and Disposal

Potential sources of chemical releases from creosote pressure treatment facilities were described in Section 5.2 and Figure 1. Table 23 identifies the main categories of process wastes or emissions that can be generated at creosote facilities, and summarizes recommended control, treatment and/or disposal methods.

The processes used for waste disposal fall under provincial jurisdiction and may vary from province to province.

Federal and provincial regimes address hazardous waste and hazardous recyclable material in different manners. Provincial requirements may also differ from province to province. Consult your provincial authority for more information.

9.2 Liquids Containing Creosote

Contaminated Storm Runoff

Because creosote wood preservation facility sites are generally large, considerable volumes of storm runoff occur from these sites. Precautions should be taken to avoid contamination of storm runoff water, particularly in the vicinity of creosote treatment areas, treated wood discharging areas and storage sites. It is good practice to roof the process areas, including the pressure cylinder and associated equipment, since this practice reduces contaminated storm runoff. Discharging areas should be paved and bermed, with provisions for collection of surface runoff. The likelihood of creosote-contaminated runoff from treated wood storage areas must be acknowledged, and surface runoff from the storage areas should be monitored for creosote and oil. If contamination occurs please refer to Section 12 - Environmental Emergency Notification and Contingency Planning for more direction.

Liquid Process Wastes

Leaks and drips of oil solutions are contained and reused in the treatment process. Liquids such as condensates, washwaters and infiltrating waters, which cannot be reused, must be treated to remove creosote and petroleum oil prior to discharge (29, 30, 31). The treatment techniques may include one or a combination of the following:

• oil/water API separation, or plate separation
• gravity separation in settling tanks
• activated sludge treatment
• activated carbon treatment
• physical-chemical treatment (e.g. flocculation)
• evaporation/condensation

A regulatory discharge permit must be obtained for disposal of the treated wastewaters.

9.3 Solids with High Creosote Concentrations

Activated carbon contaminated with creosote can be regenerated, in which case it should not be considered as waste.

It should be noted that several provinces limit the volumes of creosote wastes that can be stored.

The wood preservation industry in Canada has the following options for handling and disposal of creosote-contaminated solids:

• on-site storage until hazardous waste disposal facilities have been constructed and are operating in Canada
• shipment to the United States for high-temperature incineration
• incineration of the wastes following approval by the appropriate provincial regulatory agency
• disposal at hazardous waste landfill sites

9.4 Miscellaneous Solid Wastes

For non-bulk containers, follow recommendation from Chapter A, section 9.4. Additionnal recommendation for empty container:

• Make the empty container unsuitable for further use

Do not use creosote- treated wood as a compost or mulch.

Incineration of creosote -contaminated materials is not permitted except in facilities authorized for disposal of such products because of the formation of toxic combustion by-products

9.5 Air Emissions

Air emissions at creosote pressure treatment facilities are generally localized; effects, if any, would be restricted to workers at the facilities. Analyses of air emissions from creosote facilities indicate that the components are mostly low molecular weight organic compounds (27).