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~ ~ ~ Historic data (Tables 10 - 12) sbow fecal coliform monthly averages ranged :;, from 18 organisms/lOa .~ in February at CR-l6 to lO,973 organisms/lOa mU in July at CR-22. Further examination of historic data reveals that the standard deviation was greater tr~n the mathematical average over 90' of the time indicating large variations may exist in numbers of fecal coliform present at any sampling location. The source of the bacteria is unknown. Biological The necessary qu3ntity of benthic samples needed to compare various stretches of the r~ver bottom has not been collected to date. Samples that have been collected indicate different insect communities inr~bit different types of river substrate. A diverse group of insect larva inhabited all areas where the River provides a rubble substratei Caddis fly, Mayfly, Stone fly, beetle, and Dipteran larva. In comparison, few organis~, both in species and number, i~~bit the portions of the river substrate covered by sediments. Rocks that were covered by a t.'lln brown sediment during the Fall provided suitable habitat for caddis flies of the family Hydropsychidae and mayflies of the genus Tricorythades sp. Even fewer organisms, both in species and numbers, in.~bit the dense muck found on the river substrate. One species of caddis fly (Philopotamidas) r~t fcund elsewhere in the River and two ~yfly species, Thraulodes sp. and CyniqDa sp. were found on the muck-covered rocks down to the depth where the muck turned black. The odoriferous black muck appeaxee to provide a suitable habitat for only two species of Ch.i.ronomidae (blood wor::!) Dipteran larvae. Bot."J species possess a he~globin type blood, indicating a possible preference for an oxyqen poor or oxygen lacking enviror~ent. -15-