1989-03-01_GENERAL DOCUMENTS - C1981017

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Critique of Aquatic Ecosystem Analysis for Selected Streams on the White River National Forest - 1990 GENERAL COMIMENTS Measurements of macroinvertebrate species, biomass, diversity (DAT), biotic condition index (BCI), physical parameters, and water chemistry were obtained at various sample locations on the following White River National Forest streams: Crystal River, Dutch Creek, Bear Creek, Coal Creek The report is loosely written, and lacks a logical progression of presenting data, discussing trends, and providing conclusions. In some instances conclusions are not supported by the data. For example, data on physical parameters were not included in the report. The presence of a non-selective toxicant is only inferred. No data on constituents that could arise from coal mine operations were obtained. Therefore, speculations on toxicant contaminants, and origin have no basis. Furthermore, a macroinvertebrate analysis should tie in closely with water quality information. There should be a table which lists values for different chemical parameters. Apparently only sulfates and total alkalinity were measured. What about some of the other common measurements for water quality, such as water temperature, pH, nitrates, nitrites, dissolved oxygen, and conductivity? Were these not measured? If so, this report should include a discussion of their values. Data from stations above and below the confluence with Coal Creek should be compared statistically (e.g., Paired-T Test or ANOVA) to assess differences. Are data points means, or single samples? If means, variation among samples at a site should be evaluated. Principal concerns regarding the report are provided in the following text. SPECIFIC COMMENTS Bear Creek P.3, 12 The text implies a direct correlation between biomass and alkalinity and does not appear to consider other factors that could influence biomass, such as physical parameters and other chemical parameters. P.3 It is unusual to have only one sampling site on a stream, such as with Bear Creek. The data collected at that site may be biased by local conditions (i.e. inlet of a stream which is carrying a heavy sediment load, etc) and may not reflect the general conditions of the stream itself. Crystal River P.11, ¶ 1 Year of sampling should be indicated. "Warning numbers" should be defined.