13 
salinity in the surface layers varied widely, of course, as the 
result of dilution by discharge from the outfall, Following the 
initial dilution, later mixing occurred between effluent and diluted 
sea water, so that the effects of natural processes were over- 
shadowed by the man-made contribution. An examination of the 
tables indicates that salinity conditions around the Orange 
County outfall were relatively simple during this period. 
Hyperion 
On January 12 and 13, 1956, the salinity of the water around 
the Hyperion outfall was similar to the noted conditions at 
Orange County. A surface diluted layer surrounded the boil and 
a water mass with a uniform salinity formed the bottom layer 
(Table 4). In addition to data from these two days, oceanographic 
observations near the outfall taken during routine cruises in 
Santa Monica Bay show that near Orange County the salinity 
characteristics are relatively simple and of similar origin. 
Whites Point 
Data gathered from October 21, 1955 to February 12, 1956 show 
that salinity conditions in the Whites Point area were more complex 
than at either Orange County or around the Hyperion outfall (Table 5). 
The salinity below approximately 75 feet was fairly uniform 
with a range from about 33.4 0/oo to 33.5 o/oo. The surface 
layers, on the other hand, varied widely in response to changes 
in the adjacent land runoff and to differences in the water masses 
entering the area. Even so, most of the salinity measurements 
through the entire water column were within the range of 33.4 o/oo 
to 33.5 ofoo. Thus, the normal salinity of the water compares 
