Data are available from the analysis of 45 samples from 33 wells collected during 1993 and 1994. The data file consists of 37 variables. Variable names and codes established for sample collection are listed in table 1. Variable names for parameters measured onsite and in the laboratory are listed in table 2. To evaluate onsite-sampling variability, duplicate samples were collected from some wells. Field replicate samples were analyzed to identify variability caused by sample processing and handling. Paired t tests were used to assess differences due to filter pore size for each chemical species that had the adequate data. No statistically significant difference (at the 95% confidence level) was found between either duplicate field samples or between 0.4 and 0.1 µm filtered field samples for any chemical species. Duplicate (0.4 µm filtered) and 0.1 µm filtered samples were averaged in the final data file. Additional distilled-water blank samples, referred to as field blanks (FB) and laboratory blanks (LB), and standard reference water samples (SRWS)¹ were analyzed using the same procedures as the onsite samples. A check on the quality of the data was provided by a verification of summary statistics for the data, sorted by sample location. Table 3 reports the detection limits for all chemical constituents included in this report. Quality-assurance/quality-control statistics are shown on table 4. During 1993 and 1994, 45 samples were processed; analytical results are presented in table 5.
For further information, call Michael M. Reddy at (303) 541-3012 or contact the Chief, Branch Regional Research, Water Resources Division, Denver Federal Center, Bldg. 53, Box 25046, MS 418, Denver, Colorado 80225-0046.
