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J. A. Arruda

Publications and source records attributed to J. A. Arruda.

2 recordsLinked to original sources

Relation of trihalomethane-formation potential to water-quality and physical characteristics of small water-supply lakes, eastern Kansas

The formation of carcinogenic trihalomethanes during the treatment of public surface water supplies has become a potentially serious problem. The U. S. Geological Survey, in cooperation with the Kansas Department of Health and Environment , investigated the potential for trihalomethane formation in water from 15 small, public water supply lakes in eastern Kansas from April 1984 through April 1986 in order to define the principal factors that affect or control the potential for trihalomethane formation during the water treatment process. Relations of mean concentrations of trihalomethane-formation potential to selected water quality and lake and watershed physical characteristics were investigated using correlation and regression analysis. Statistically significant, direct relations were developed between trihalomethanes produced in unfiltered and filtered lake water and mean concentrations of total and dissolved organic carbon. Correlation coefficients for these relations ranged from 0.86 to 0.93. Mean values of maximum depth of lake were shown to have statistically significant inverse relations to mean concentrations of trihalomethane-formation potential and total and dissolved organic carbon. Correlation coefficients for these relations ranged from -0.76 to -0.81.

Kansas↗

Water-quality reconnaissance of selected water-supply lakes in eastern Kansas

Data collected for 19 public water-supply lakes in eastern Kansas during spring-fall 1983 were statistically analyzed to describe relationships between water-quality constituents and lake and watershed physical characteristics. A large range was observed in mean concentrations of total nitrite plus nitrate nitrogen, total ammonia nitrogen, total phosphorus, total organic carbon, and chlorophyll a and in lake and watershed physical characteristics, such as age, surface area, watershed area, watershed-to-lake surface-area ratio, and average maximum depth. Pesticides were detected in 8 of the 19 lakes. Atrazine and Alachlor were the most commonly detected pesticides. Spearman rank-order correlation analyses showed possible relationships between mean concentrations of total nitrite plus nitrate nitrogen, total ammonia nitrogen, total phosphorus, total organic carbon, and chlorophyll a, and certain lake and watershed physical characteristics. Multiple-regression analysis produced significant relations between mean concentrations of total nitrite plus nitrate nitrogen and percentage of watershed in protected cropland and age of lake (0.62 coefficient of determination), and between mean concentrations of total organic carbon and lake average maximum depth, lake-surface area, age of lake, and watershed-to-lake surface-area ratio (0.76 coefficient of determination). (USGS)

Water-Resources Investigations Report↗