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Air Quality

Our air emissions have been steadily declining. Air emissions from Weyerhaeuser facilities come primarily from two sources:

  • Industrial boilers that burn fuel to produce electricity and steam and recover chemicals used in the pulping process
  • Airborne chemicals released in the production of wood, pulp and paper products

Air Quality Measures

Boiler replacements and upgrades at pulp and paper mills have a positive effect on air quality. Between 2000 and 2008, our cellulose fibers facilities reduced their SO2 emissions by 13 percent and their particulate matter emissions by 45 percent. In our wood products mills, we’ve reduced air emissions of volatile organic compounds by 15 percent since 2000. Also since 2000, our wood products and cellulose fibers facilities reduced air emissions of particulate matter per ton of production by 61 percent and nitrogen oxides by 24 percent. This trend is the result of process modifications and the use of lower-emitting additives as well as pollution-control equipment that has captured or destroyed a significant amount of emissions.

Our strategy for reducing air emissions evaluates cost effective options including process changes, efficiency improvements, and, when necessary, add-on pollution control equipment. Our approach is to determine the most effective means to meet regulatory requirements and improve performance while minimizing greenhouse gas and conventional air pollutant emissions.

Cellulose Fibers — Air-Quality Measures
Estimated pounds emitted per ton of production1
2004 2005 2006 2007 2008
Nitrogen oxides 4.6 4.5 4.4 4.7 4.4
Particulate matter 1.7 1.5 1.3 1.2 1.1
Sulfur dioxide 3.0 3.3 3.4 3.3 3.1
Total reduced sulfur 0.3 0.2 0.1 0.1 0.1
  1. Data reflects performance of Weyerhaeuser’s 2009 portfolio of cellulose fibers mills. In March 2007, Weyerhaeuser’s fine paper business and related assets were combined with Domtar Inc. to create a new fine paper company, Domtar Corporation. In August 2008, Weyerhaeuser’s containerboard, packaging and recycling business was sold to International Paper. Operations involved in those transactions have been removed from historical data.

Wood Products Facilities — Air-Quality Measures
Estimated pounds emitted per ton of production
2004 2005 2006 20071 2008
Carbon monoxide 3.1 2.5 3.1 2.1 2.06
Volatile organic compounds 1.3 1.3 1.4 1.4 1.52
Particulate matter 0.8 0.8 0.8 0.9 0.55
Nitrogen oxides 0.5 0.6 0.6 0.6 0.65
  1. In March 2007, Weyerhaeuser’s fine paper business and related assets were combined with Domtar to create a new fine paper company, Domtar Corporation. Sawmills included in the Domtar transaction are not part of 2007 data.


Canadian Criteria Air Contaminants Reporting
Estimated metric tons released from Weyerhaeuser's Canadian manufacturing facilities
2003  2004  2005  2006  20071
Oxides of nitrogen (as NO2) 5,508 4,965 5,246 4,494 1,298
Carbon monoxide 23,331 16,433 14,264 14,268 3,292
Sulfur dioxide 1,415 1,307 1,402 1,810 1,717
Total particulate matter 5,539 4,258 4,066 3,849 828
Particulate matter < 10um 3,899 3,130 3,000 2,881 668
Particulate matter < 2.5um 3,128 2,556 2,492 2,231 568
Volatile organic compounds 4,607 4,502 3,985 3,397 1,377
TOTAL Canadian Weyerhaeuser operations2 40,400 31,465 28,963 27,818 8,505
  1. 2007 is the most recent reporting period.
  2. Total does not include particulate matter < 2.5um and a particulate matter < 10um as they are sub-sets of total particulate matter.

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Limited Use of Methyl Bromide

The forest products industry uses methyl bromide, in a targeted and careful way, to prevent seedling mortality by harmful insects, weeds and disease-causing organisms in tree-seedling nursery beds, and product shipments as appropriate to meet quarantine pest control requirements. In accordance with the Montreal Protocol, countries are phasing out substances that deplete the ozone layer. Methyl bromide is one such substance.

Within the Protocol, industry can still legally use methyl bromide to prevent the spread of designated quarantine pests, which can include diseases, insects and invasive weeds. The ability to use methyl bromide and other chemicals in forest nurseries enables a very small overall nursery land base to supply the planting stock necessary to promptly plant thousands of acres of forest land annually, with the corresponding significant environmental and societal benefits that healthy working forests bring. Weyerhaeuser uses methyl bromide carefully in targeted and limited applications. For example, we achieved a 22 percent reduction in pounds of methyl bromide applied per acre in our Washington and Oregon tree nurseries between 2001 and 2008.

Weyerhaeuser has been a leader in research to develop alternatives to methyl bromide for forest nursery use in partnership with a number of other agencies and sponsors. This research has met with some success, but no other fumigants or other alternatives evaluated to date have shown efficacy across the range of climate, soil type and pest conditions. As global supplies of methyl bromide continue to decline, the industry will depend heavily on manufacturers and distributors to step up with effective, cost-effective, environmentally sound alternatives and the technology to apply them safely.

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Last updated Jun. 1, 2009.