Sample Collection and Laboratory Analysis

All sampling events (defined here as field trips to the Ely Copper Mine Superfund site where at least one sample was collected) occurred during the years 1998 to 2007, between early spring and late fall (April through November); the majority occurred May through September. A general summary of the sampling events is in table 1. Frequency of sampling events varied from hourly to annually. The matrix of samples collected (water, sediment, soil, fish, or macroinvertebrate) also varied among sampling events. About 60 percent of the total sample locations (n=154) had multiple sample-matrix types collected. Surface-water and stream-sediment samples were the most frequently collected samples. Samples were collected according to the sampling agency’s protocols, which varied among the different agencies.

Samples were primarily analyzed for a suite of inorganic elements, alkalinity, nutrients, and some organic elements. Field parameters were determined for most surface-water and pore-water samples (specific conductivity, pH, oxidation reduction potential, temperature, and dissolved oxygen). Not all samples were analyzed for the same constituents; most samples, however, were analyzed at least for the 23 contaminats identified by USEPA (Stan Pauwels, Techlaw, Inc., written commun., 2007) to be of potential concern for aquatic health: Al, Sb, As, Ba, Be, Cd, Cr, Co, Cu, Fe, Pb, Mn, Hg, Mo, Ni, Se, Ag, Sr, Tl, Sn, V, Zn, and Cyanide.

The datasets that contain chemical analyses include a "Method" column. Information contained in this column is either a brief description, an abbreviation, an acronym, a numeric code, or a name for the method of analysis. The original data files did not include references for the method of analysis; however, USGS methods are described in Brenton and Arnett, 1993; Briggs, 2002; Briggs and Meier, 2002; Fisherman, 1993; Lamothe and others, 2002; Patton and Kryskalla, 2003; Sholar and Shreve, 1998; Sobek and others, 1978; Theodorakos and others, 2002.

Table 1 is available as a pdf.