On May 30, 1968 G.C.O.S requested permission to discharge 110 x 106 ft3 of effluent from the sands tailings pond at the Fort McMurray site into the Athabasca River during periods of high river flow. G.C.O.S. outlined the events which made this request necessary in order that an adequate base be developed for a stable 200 foot dike. Samples of the tailings pond water were obtained on June 3, 1968 to assess it’s compatibility with the river water. Samples of the A.P.I. separator retention pond effluent, waste water storage pond, and Lake Athabasca were also obtained. Analytical data suggest that a discharge of 10 x 106 I .G.P.D. from the Tailings Pond would minimize effects on the Athabasca River and yet allow the discharge of 110 x 106 ft3 to occur during a 2 month period when river flows exceed 20,000 c.f.s. Sedimentation of the high solids content could be induced by directing the Tailings Pond water to the retention ponds prior to discharge from the waste water storage pond. Assuming that the regular process waste water discharge is maintained at 10 x 106 I.G.P.D., settling time of the Tailings Pond water (10 x 106 l.G.P.D.) would be 7 hours in the retention ponds and 8.4 days in the waste water storage pond.

GCOS requested permission to discharge effluent from the sands tailings pond at the Fort McMurray site into the Athabasca River during periods of high river flow. GCOS outlined the events which made this request necessary in order that an adequate base be developed for a stable 200 foot dike.