TRACING THE SOURCE AND FLOWPATH OF CONTAMINATION BY OIL BRINE IN A SHALLOW PHREATIC AQUIFER

Jozsef Toth in his 1963 paper “A theoretical analysis of groundwater flow in small drainage basins” expanded on M.K. Hubert's 1940 “Theory of groundwater motion.” The two papers provided practicing hydrogeologists with an effective tool facilitating determination of the fate of any miscible contaminant entering a phreatic aquifer with recharge water. In Ohio, 1985 H.R. Bill 501 authorized the local jurisdictional authorities to issue permits to use oil-field brine surface spreading as dust and ice control agent. Such permits are usually given without any hydrogeological consultations as to the potential impact on the shallow aquifers, particularly if the brine spreading occurs in a recharge area. One such case occurred in the southwestern suburb of the City of Wooster, Ohio, where a group of home owners were seeking judicial relief when their water wells began yielding salty water as a result of brine spreading on a nearby large open storage area for oil and gas well drilling supplies. The defendant, owner of the storage yard amassed, under advice of his own consultant an excellent hydrogeological and hydrochemical data set (including stable isotopes' analyses along with the complete chemical analyses of major and minor constituents), allowing construction of flow net profiles and establishing fresh groundwater-brine mixing system. The data, however clearly implicated his company as the source of the salts in the residential water wells, and the case was settled out of court, releasing all the data for this presentation.