From McGimsey and others (1995): "Southerly winds carried the ash cloud northward over the Alaska Range with ashfall reported as far as 420 km north of Mount Spurr. The bulk volume of the tephra erupted is estimated to be 44 x 10^6 cubic meters. Small-volume pyroclastic flows mixed with snow and ice to form hybrid flows that swept down the south side of the cone to the Chakachatna River, 6 km from the crater (Waitt, 1995). The eruption destroyed the crater rim seismic station located 400 m from the vent."Aircraft
From Smithsonian Institution (1993): "Because the plume was carried northward, major air routes to Asia that extend along the Aleutian chain from Anchorage were not affected. A Notice to Airmen warned aircraft to avoid the immediate vicinity of the volcano. No routes were officially closed, but airlines avoided using routes N and NW of the volcano (J501, 111, 133, 120, and 122; and V319, 444, and 480) during the eruption. Flights arriving in Anchorage, 120 km E of Spurr, were routed along normal approaches from the south."