Element concentration intervals, copper

Figure 9. Left digital photograph ofa selected area ofsample WJJ122, followed by elemented contour maps of iron, copper, and manganese concentrations on the surface of the sherd. Darker areas on the contour maps indicate higher elemental concentrations for that element. The analyzed area is 10 x 18 mm. Sampling was conducted at 1 mm intervals.

The concentration intervals Ii through I5 for each element were chosen by inspecting the range of abundances using all 1027 analyses of native copper. By using the data shown in Table I, the intervals were chosen to distribute the concentrations as evenly as possible throughout the five I cells. Because many concentrations were below the detection limit, the lowest concentration interval (which includes not detected )... 

The EPA mobile lab analyzed soil samples for lead, zinc, copper, and nickel by XRF. Because arsenic had been identified as the element that presents the greatest risk to human health at the Cos Cob site, samples from the 0—1 ft (0—0.3 m) to 1—2 ft (0.3-0.6 m) intervals were sent off-site for analysis by inductively coupled plasma/ atomic emission spectrometry. If the off-site analysis showed arsenic concentrations greater than 10 ppm (the Connecticut direct exposure criterion for soil), the field investigators progressively analyzed samples in 1 -ft (0.3 m) intervals below and surrounding the sample, delineating hot spots, until the remaining contamination was lower than 5 ppm. 

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