Gschwend%20thesis.pdf

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~aphthalenes. The naphthalenes showed a different temporal function in
their concentrations (figure 3-14). The March 8, 1977 sample was rich
in these compounds (as it was for alkylated benzenes). Examination of
the isomer relations at CD and those from a sample of no. 2 fuel oil
reveal identical patterns (Schwarzenbach et al., 1978). Thus direct
input of oil was the most likely source of these compounds at that time.
However, two weeks after the next sample was taken, the seawater concen-
tration of these compounds had decreased dramatically. As noted in
Schwarzenbach et al. (1978) a period of intense storm activity between
these two samples may have been responsible for this thorough flushing.
It is difficult to identify either the atmosphere or the sediments as the
ultimate sin~ as transfer to either reservoir would be enhanced during
storm-induced introduction of bubbles or particles into the water.
Naphthalenes also showed relatively high levels in the winter of
1977-l978. Possibly this may be attributed to the use of home heating
oil a t this time of year.
The homologue ratios may add some insight into the source of naphthalenes
throughout the year. By analogy to the higher polycyclic aromatic hydrocar-
bons, the ratio of naphthalene to the sum of the Cl -naphthalenes may
reflect the temperature of formation of the source material (Blumer and
Youngblood, 1975a, 1975b, and 1976) as well as the environmental transport
processes which brought them to CD (Laflame and Hites, 1978). For
example, if a high temperature source was responsible, naphthalene
concentration should be greater than that of the methyl substituted
compounds. If atmospheric transport of the compounds to CD has occurred,
the ratio may increase as the lighter naphthalene exhibits a higher vapor
pressure and therefore is more easily volatilized. Obviously, the possible
combinations of source ratios and their environmental transformations are
numerous and complex.