EPA sampled four placer mines in Alaska during the summer of 1998. This was the second phase of a study of the distribution of metals in surface water at placer mines in surface water upstream of the mine site, downstream of the mine discharge, and in the effluent. The second phase examines temporal variations from eight rounds of measurements collected during 1998 from four placer mines located in three mining districts. During the second phase in 1998, EPA obtained field measurements of temperature, pH, electrical conductivity, dissolved oxygen, turbidity, and settleable solids. In addition, EPA analyzed samples for total suspended solids, total recoverable metals, dissolved metals, and hardness. The metals analyses included aluminium, antimony, arsenic, cadmium, calcium, chromium, copper, lead, magnesium, mercury, nickel, selenium, silver, and zinc. The 1998 data show typically large variations in total recoverable and dissolved metals concentrations through the course4 of the mining season. Consistent with 1997 results, turbidity was an effective indicator for some, but not all, total recoverable metals found in surface waters. In addition to turbidity, total suspended solids measurements showed similar variations with total recoverable metal content.