These studies determined that effluents and digested sludge discharges 

 from the Hyperion Plant include significant amounts of organic and 

 mineral constituents. These amounts cause measurable effects in the 

 various animal and plant populations of the receiving waters and bottom 

 sediments. The observed total effect of both the effluent discharge at 

 50 feet and the digested sludge at 320 feet, is to increase the standing 

 crop of plankton and animals in the Bay. Maximum populations, however, 

 were found at some distance from the outfalls. Fish were obtained from 

 every station on every trawl. Bio-assays showed no toxic effects on 

 test fish caught outside the immediate vicinities of the discharges. 

 The deposits from the sludge outfall were found to be stabilized by 

 several species of marine worms which attained densities of as many as 

 200,000 per square mile. 



In addition, between 1958 and 1963, the California Department of 

 Fish and Game in cooperation with the City of Los Angeles, Bureau of 

 Sanitation, in order to determine the effects of waste disposal on fish 

 populations, conducted bottom trawl studies in Santa Monica Bay (Carlisle, 

 1969) . The data indicated local changes in the vicinity of the waste 

 outfalls. It was impossible to demonstrate that fluctuations in the 

 abundance of species were the result of waste discharges in the study 

 area and not due to natural causes. Certain fish species avoided areas 

 of high waste concentration; other species were attracted. However, it 

 was suggested that species diversity in the discharge areas may be lower 

 than in waste-free areas. 



Another study (Carlson and Zichefooze, 1965) indicated that California's 

 giant kelp (Microcystis pyrifera) is being adversely affected by increases 

 in sea urchin populations apparently nurtured by waste disposal. This 

 kelp once constituted a prominent and probably dominant ecological factor 

 of the coastal environment. Between 1945 and 1965 the kelp beds became 

 substantially diminished near the sewage outfalls from Los Angeles and 

 Santa Barbara. 



A study of the effects of discharged wastes on kelp was published 

 by the California State Water Quality Control Board (1964). This study 

 concluded that turbidity of the water due to outfall discharges may be 

 a significant factor. No direct relationship, however, was established 

 between particulate wastes as a major factor of turbidity and kelp pro- 

 duction. The reduction in the extent of kelp beds, and the decrease of 

 coastal fisheries in this area may be coincidental, and cannot be attri- 

 buted exclusively to waste discharges. 



Another study sponsored by the Sport Fishing Institute (SFI) , a 

 predecessor component of EPA, could not associate turbidity with the 

 ecology of the giant kelp. The evidence related reduction of kelp beds 

 to the addition of nutrients from sewage (such as free amino acids) 

 rather than to possible effects of particulate matter. It was believed 

 that these nutrients are extensively absorbed from the sea water by 

 urchins, which are the natural grazers of kelp, resulting in an increase 

 and dominance of urchin populations. A series of warm-water years in 



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