Contents Notes |
Report identifies potential indicators of urban environmental copper trends (street dirt, storm water runoff, aquatic organisms). After a discussion of issues of environmental sample variability, identifies the number of "before" and "after" samples of various media that would be needed to determine with statistical significance a 25% or a 50% change in copper levels in the measured medium. For a 25% change, 40 before and after samples of urban runoff, 40 street dirt samples, and 14 clam samples would be needed. For a 50% change, 10 before and after urban runoff samples, 10 street dirt samples, and 6 clam samples would be needed. Report includes rough cost estimates for sampling (1999 costs) and recommendations for consideration should a sampling program be pursued. |