STUDIES ON COLIFORM BACTERIA 
DISCHARGED FROM THE HYPERION OUIFALL 
FINAL BACTERIOLOGICAL REPORT 
Introduction 
A previous report entitled “The Fate of Coliform Bacteria 
in the Vicinity of the Orange County, Los Angeles County, and 
Hyperion Sewer Outfalls, May 1, 1956"! dealt with the bacterio- 
logical data collected between September 1955 and March 1956. 
Subsequently, six additional trips were scheduled to obtain 
the additional information required before final conclusions 
could be drawn. This report presents only the new data, but 
the discussions and conclusions are based on all of the available 
bacteriological information, including that in the previous 
report. Consequently, the May 1 report should be considered an 
integral part of this final report. 
Of the six trips made, two were concerned with the collection 
and analysis of coliforms in sediments from the Orange County and 
Santa Monica Bay areas. The remaining four trips were in Santa 
Monica Bay during periods when unchlorinated primary effluent 
was being discharged from the Hyperion outfall. On one trip a 
radioactive tag was added to the effluent at the plant to serve 
as a tracer. The data from this trip are presented first out of 
chronological order because of their significance in substan- 
tiating the validity of other types of information collected. 
No description of field or laboratory methods are included 
in this report unless they differ from those described in the 
May 1 report. 
1. Referred to in the text as the “May 1 report™. 
