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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 2007, our pulp and paper facilities have reduced their SO2 emissions by 22 percent and their particulate matter emissions by 46 percent. In our wood products mills, Weyerhaeuser has reduced air emissions of volatile organic compounds by 28 percent since 2000. Also since 2000, our wood products and pulp and paper facilities have reduced air emissions of particulate matter per ton of production by 52 percent and nitrogen oxides by 14 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.

Pulp and Paper Mills — Air-Quality Measures
Estimated pounds emitted per ton of production at Weyerhaeuser's North American pulp and paper mills1
2003 2004 2005 2006 20072
Nitrogen oxides 4.5 4.4 4.5 4.4 4.1
Particulate matter 1.9 2.0 1.6 1.5 1.1
Sulfur dioxide 3.2 2.6 2.7 2.5 2.8
Total reduced sulfur 0.3 0.3 0.5 0.1 0.1
  1. 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. Operations included in the Domtar transaction are not part of 2007 data.
  2. 2007 includes data from our Xalapa, Mexico, mill.

Wood Products Facilities — Air-Quality Measures
Estimated pounds emitted per ton of production at Weyerhaeuser's North American wood products facilities
2003 2004 2005 2006 20071
Carbon monoxide 3.1 2.9 2.4 3.1 2.0
Volatile organic compounds 1.4 1.1 1.3 1.3 1.4
Particulate matter 0.9 0.8 0.7 0.8 0.8
Nitrogen oxides 0.5 0.5 0.5 0.6 0.6
  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.

Corrugated Packaging, Bag and Recycling Plants — Air-Quality Measures
Estimated pounds emitted per ton of production at Weyerhaeuser's U.S. corrugated packaging, bag and recycling plants
20041 2005 2006 20072
Carbon monoxide 0.07 0.06 0.06 0.05
Particulate matter 0.11 0.13 0.14 0.14
Nitrogen oxides 0.10 0.09 0.08 0.07
Volatile organic compounds 0.19 0.20 0.16 0.18
  1. Packaging and bag plant data first collected in 2004.
  2. Data from recycling plants and Mexico operations first collected in 2007.

Canadian Criteria Air Contaminants Reporting
Estimated metric tons released from Weyerhaeuser's Canadian manufacturing facilities
2002  2003  2004  2005  20061
Oxides of nitrogen (as NO2) 8,240 5,508 4,965 5,246 4,494
Carbon monoxide 31,861 23,331 16,433 14,264 14,268
Sulfur dioxide 1,420 1,415 1,307 1,402 1,810
Total particulate matter 6,186 5,539 4,258 4,066 3,849
Particulate matter < 10um 4,605 3,899 3,130 3,000 2,881
Particulate matter < 2.5um 3,691 3,128 2,556 2,492 2,231
Volatile organic compounds 5,674 4,607 4,502 3,985 3,397
TOTAL Canadian Weyerhaeuser operations2 53,380 40,400 31,465 28,963 27,818
  1. 2006 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 2007.

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 May 27, 2008.