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<br />002348 <br /> <br />The bottom-sediment sample from Sweitzer Lake collected in November was <br />composited from several samples spooned from shallow areas on the south side <br />of the lake. The availability of fine bottom sediment at the stream sites was <br />limited; therefore, bottom-sediment samples were scooped from areas of depo- <br />sition using stainless-steel spoons and were composited in a bucket. Bottom <br />sediment was mixed in the bucket, and subsamples were taken for inorganic <br />analysis and for pesticide analysis where applicable. The lake was resampled <br />in January using an Ekman dredge. <br /> <br />Biological samples were collected by the u.s. Fish and Wildlife Service <br />using standard equipment and techniques (U.S. Fish and Wildlife Service, 1986 <br />and 1990). Birds were shot using steel shot, and livers were removed using <br />stainless-steel dissecting equipment. Based on the literature, bird liver was <br />determined to be the best organ for a general trace-element scan, although <br />other organs may be better indicators for specific elements (such as kidney <br />for cadmium and bone for lead). Dissecting equipment was cleansed using water, <br />soap, and solvent (U.S. Fish and Wildlife Service, 1990) prior to removal of <br />each liver. Bird livers were placed in chemically cleansed jars, weighed, and <br />frozen. Livers from each bird group were sometimes composited with two or <br />three livers into one sample. <br /> <br />After locating nests, bird eggs were removed, the egg volume was deter- <br />mined by water displacement, and eggs were cracked open to examine embryos for <br />developmental abnormalities. After examination, eggs were placed in chemi- <br />cally cleansed jars, weighed, and frozen. Small eggs were composited to <br />provide sufficient biomass for analysis. <br /> <br />Fish were collected using electroshocking equipment and seine or gill <br />nets. Fish were rinsed, weighed, measured for length, and immediately frozen <br />on dry ice until storage in a freezer. Whole-body samples were composited by <br />species into groups of three or more fish as dictated by the DOl sampling <br />protocol. Fish for analyses of inorganic contaminants were frozen in plastic <br />bags. Fish samples for analyses of pesticides were wrapped in aluminum foil <br />and placed in plastic bags. <br /> <br />Stream invertebrates were collected using a kick screen, and lake inver- <br />tebrates were collected using a sweep net. Because this was a reconnaissance- <br />level study, several easily identifiable invertebrate groups were combined to <br />obtain sufficient biomass for analysis. Vascular plants and algae were col- <br />lected by hand. These samples were placed in chemically cleansed jars, <br />weighed, and frozen. Algae samples contained green algae (Chlorophyta) and <br />blue-green algae (Cyanophyta), and plankton samples consisted of phytoplankton <br />and zooplankton. <br /> <br />Analytical Support <br /> <br />Analyses of water samples for major constituents and trace elements <br />(except uranium) were done by the U.S. Geological Survey's National Water <br />Quality Laboratory in Arvada, Colorado, using analytical methods described in <br />Fishman and Friedman (1989). Uranium analyses were done by a private <br />laboratory, contracted by the U.S. Geological Survey, using a method <br />described in Thatcher and others (1977). Pesticide analyses of water and <br /> <br />35 <br />