Studies in Porpoise Channel, Porpoise Harbour and Wainwright Basin during 1986 encompassed physical, chemical, and biological assessments of the local environment. These parameters ultimately being related to the discharge of kraft pulpmill effluent into Porpoise Harbour (Figure I) by Skeena Cellulose Inc. Water samples were collected by Skeena personnel and analyzed in the mill laboratory; tide information was also recorded. Water quality data consisted of water temperature, dissolved oxygen, pH, turbidity, tannins/lignins, colour, and salinity. Percent saturation dissolved oxygen was calculated.