Em. Vanwarmerdam et al., STABLE CHLORINE AND CARBON-ISOTOPE MEASUREMENTS OF SELECTED CHLORINATED ORGANIC-SOLVENTS, Applied geochemistry, 10(5), 1995, pp. 547-552
Stable Cl and C isotope ratio results for 3 selected chlorinated solve
nts, perchloroethylene (PCE), trichloroethylene (TCE) and 1,1,1-trichl
oroethane (TCA) provided by 4 different manufacturers are presented. T
he isotope ratio for all compounds range between -3.5 and + 6.0 parts
per thousand for delta(37)Cl and from -37.2 to -23.3 parts per thousan
d for delta(13)C. The greatest Cl-37 difference between manufacturers
is observed in the TCE samples which show delta(37)Cl values of -2.5 p
arts per thousand for PPG, + 2.4 parts per thousand for ICI and + 4.4
parts per thousand for DOW. TCAs show a smaller range (-2.4 to +2.0 pa
rts per thousand), while the TCEs have slightly different Cl-37 conten
ts. The C-13 data show the most distinct delta(13)C values for PCEs (-
23.3 for DOW, -24.1 for Vulcan, - 33.8 for PPG and - 37.2 parts per th
ousand for ICI) while both TCEs and TCAs show a smaller delta(13)C ran
ge, but still distinct differences. These preliminary data suggest tha
t each manufacturer and solvent type may have distinctive delta(37)Cl
and delta(13)C values. These results show that by using a combination
of Cl-37 and C-13, there is a potential to indicate a specific source
of chlorinated solvents, as well as an ability to delineate contaminat
ion episodes caused by these compounds in groundwaters.