Pulp and paper mills are present throughout the upper and lower Fraser Valley, and comprise a significant industry in Upper Fraser towns. Their presence provides a source of employment, but there are some environmental impacts associated with pulp and paper mills, depending on the type of processes that they use.
A pulp mill is the first part of the process in manufacturing paper and tissue. It converts wood chips and other plant material into a thick board, which is then sent to a paper mill for further processing. The pulp can be bleached or unbleached. There are two types of pulp mills: chemical and mechanical.
A mechanical pulp mill uses a large amount of energy and manufactured stones to grind the plant material into a pulp. A chemical pulp mill uses a process called Kraft that uses chemicals such as sodium hydroxide and sodium sulphide to break down the plant/wood material to a refined pulp.
This pulp is generally stronger than other pulp produced by the mechanical process. The pulp may be bleached using another chemical process. To brighten the pulp, a one modern technique called Elemental Chlorine Free uses chlorine dioxide as opposed to elemental chlorine; other techniques such as Total Chlorine Free do not use chlorine .
Paper mills can be at the same location as a pulp mill and use large amounts of water, energy and wood pulp to produce paper.
Environmental Impacts
There are some environmental impacts resulting from pulp and paper mills that are pertinent to the Fraser River. Many chemicals may be used in the pulp process, such as toxic solvents, biocides that act to prevent bacterial growth in the pulp, and oxygen-consuming substances. These chemicals, if not properly treated, can be part of effluent that ends up in surrounding waterways that could, in turn, affect migrating salmon.
Detailed information on the National Pollution Release Inventories to air, water, and land for different industries can be located on the Environment Canada website (http://www.ec.gc.ca/inrp-npri/default.asp?lang=en).
