Pulp Mill Wastewater Loads

Indicator Type: Environmental Pressure

This indicator shows daily loads of treated wastewater released by all seven Alberta pulp mills, averaged annually. Biochemical Oxygen Demand (BOD) is a measure of the amount of oxygen needed to breakdown organic matter in the wastewater. This is the main measurement of concern in monitoring pulp mill wastewater. Total pulp production is also presented to show how wastewater loads relate to the mills' production.

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Trend: Improving

What does the indicator show?

This indicator shows that the total biochemical oxygen demand load of all pulp mill effluent has declined during the period of record. This has occurred even though pulp production over the same period has more than doubled. This reflects improvements in mill processes and wastewater treatment by the industry. All mills release less than their current approval release limit for biochemical oxygen demand.

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Why is this indicator important?

Biochemical oxygen demand measures the amount of oxygen required to breakdown organic material in the effluent. This decomposition of organic matter consumes oxygen in the receiving water. If the biochemical oxygen demand is high enough, it can reduce dissolved oxygen levels in the receiving water. This creates stress on the fish and other aquatic animals. Oxygen depletion resulting from the breakdown of organic wastes is particularly important during the winter. This is because river flows are low then and the river is deprived of new oxygen from the air by ice cover.

The pulp mill industry in Alberta underwent a major expansion in the 1988-93 period. Collectively, pulp mills now release the largest volume of treated process wastewater of any industry in Alberta.

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What actions are being taken?

Pulp mills are issued approvals to operate by the provincial government. These approvals set out requirements for wastewater release quality. Alberta Environment's policy is for continuous improvement in the environmental performance of Alberta pulp mills. As approvals come up for renewal, the mills are required to investigate and propose ways of improving wastewater quality. In addition, water quality concerns in the waters that receive the wastewater can dictate that wastewater treatment and limits be reviewed at any time. Monitoring continues for biochemical oxygen demand and other contaminants in pulp mill wastewater (such as total suspended solids and absorbable organic halides). Monitoring of receiving rivers is also performed by the pulp mill companies and by Alberta Environment. The purpose is to assess and address any potential environmental impacts.

The federal government has its own Pulp and Paper Effluent Regulations established under the Fisheries Act. The provinces are allowed to set standards that are more stringent than the federal requirements. A comparison of limits set by the federal government and some other provinces is shown below:

Comparison of Wastewater Release Limits (Monthly Average)

	Biochemical Oxygen Demand (kg/tonne)
Alberta	1.5 to 3.0
Canada	7.5
Ontario	5.0
British Columbia	7.5

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Links to additional information

Alberta Forest Products Association: http://www.albertaforestproducts.ca/home/

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Feedback

E-mail the SOE Coordinator: SOE.Coordinator@gov.ab.ca or complete this short on-line questionnaire to provide your feedback: http://www.zoomerang.com/
survey.zgi?p=WEB224DW6P3E2K.

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