
BARTON, ANDREW C., and BAIR, E. SCOTT, The Ohio State University, Columbus, OH
A two-phase study was designed to evaluate ground-water quality changes
resulting from land spreading of oil and gas field cuttings at a site in
central Ohio. During the first phase, approximately 20 cubic yards of non-solidified
saturated cuttings was spread over a 1500 square foot area adjacent to
11 monitoring wells used to obtain ground-water samples for analysis of
major ions and trace metals. An EM-131 Earth Conductivity Unit also was
used to track subsurface movement of any leachate. A brine plume delineated
by elevated chloride concentrations and elevated specific conductivity
values developed downgradient of the applied cuttings and moved quickly
off the site following periods of rainfall.
The second phase of the study involved land spreading of saturated
cuttings mixed with a solidifying agent. Column experiments were performed
using the cuttings both alone and mixed with several industry-approved
solidifying agents to determine the effectiveness of each agent in minimizing
the leaching of major ions and trace metals. Based on these tests, Portland
cement is likely to be mixed with saturated cuttings and applied to the
field site for the second phase.
The results of this study are expected to provide the oil/gas industry
with a viable and environmentally acceptable alternative to solidification
and burial of wastes in brine pits. In spreading the brines in such a way,
available surface area is increased, allowing for greater dilution and
absorption resulting in reduced contamination in the subsurface.