Deep Sea Ocean Disposal of Petrochemical
Plant Wastes
JOHN BALL, Assistant Professor
TOM D. REYNOLDS, Associate Professor
Department of Civil Engineering
Texas A & M University
College Station, Texas 77843
DANIEL E. BECKETT, Engineer
Texas Water Quality Board
Austin, Texas 78701
INTRODUCTION
Until 1973, ocean dumping of petrochemical wastes was essentially the responsibility
of the industries themselves. However, with the passage of the Marine Protection Research
and Sanctuaries Act of 1972, the Environmental Protection Agency (EPA) was designated
as the entity responsible for issuing ocean dumping permits according to the policies set
forth in the Act and in subsequent guidelines (1, 2).
The initial round of permits issued by the EPA in the spring of 1973 specified that each
industry dumping petrochemical wastes off the Texas coast discharge the wastes in a
common dumping grounds 100 miles south-southeast of Freeport, Texas beyond the 100
fathom contour and to conduct three studies. These studies included: 1) bioassays of the
waste; 2) in situ bioaccumulation studies; and 3) in situ dispersion studies.
Five petrochemical plants applied for permits during the first year of the program with
three of the plants being owned by one company. The authors performed a joint in situ dye
dispersion study for the three plants owned by the one company and a second study for the
fourth plant. The fifth plant conducted its own study. The results of the two dispersion
studies are presented in this paper along with several previous studies in the literature with
an analysis of all the data and the development of a formula that describes the dispersion
phenomena.
PREVIOUS DYE DISPERSION STUDIES
Ketchum and Ford Study
One of the original barge dispersion studies was conducted by Ketchum and Ford of
the Woods Holes Oceanographic Institution in 1948 and 1950 (3). The waste consisted of
about 10 percent FeS04 and 8.5 percent H2S04 in water. About 3,000 tons of waste were
discharged into the wake of the barge through two 12-inch pipes at keel depth which would
range from 15 feet below the water surface when fully loaded to six feet when the barge was
empty. The waste was pumped from the barge at rates of from 32,000 to 78,000 lbs/min
while the barge was towed at a speed of six knots.
A total of six dispersion runs were conducted each at a different discharge rate between
April 22, 1948 to January 4, 1950. The field procedure was to follow the barge with a
research vessel and detect the distribution of iron concentration in the wake of the barge
with time. The data was converted from the values obtained in the paper to iron
concentration in the wake at various times after discharge. The iron concentrations were
plotted versus time on log-log paper as shown in Figure 1. The data plotted as a straight line
with the high discharge rate data of 78,000 lbs/min giving a somewhat higher concentration
after dumping as would be expected. This would indicate that an increase in discharge rate
of from 1.3 to 2.4 times would result in approximately double the waste concentration in the
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