(GP/GT) for Additional Water Supply in the Lower Rio Grande

evaluation of geopressured-geothermal brine as a potential remediation
technology. Dense non-aqueous phase liquids (DNAPL) greatly complicate
groundwater remediation because the heavy DNAPL will sense and follow
topographic lows within an aquifer system, and because DNAPL is difficult to
extract using conventional pumping methods. These problems are now being
observed at the Motco Superfund Site near Houston, TX, where DNAPL is present
in a shallow surficial aquifer. As observed in pilot test activities,
waterflooding and well-bore vacuum enhanced recovery increased recovery rates
(Conner, 1990).
The use of geopressured fluids for the remediation or removal of hazardous
wastes, or both, appears to have significant potential for development,
especially considering the increasing emphasis on controlling hazardous
wastes. Accordingly, a separate feasibility study is being prepared by the
INEL.
Thermal Enhanced Oil Recovery
Geopressured resources, often encountered while drilling for oil and gas,
can provide hot brines under pressure to flood reservoirs containing medium or
heavy oils to enhance recovery. The INEL is proposing a program for the
thermal enhanced recovery of heavy oil from the Alworth Field in the "Mirando"
trend of south Texas. It is not possible to consider a hot water-steam type
flood in this part of Texas because of the lack of steam quality fresh water;
however, geopressured brines can be considered. In the San Joaquin Basin of
California, cyclic steam injection has been used successfully but is now under
scrutiny because of the pollution generated by the equipment used in producing
the steam; in contrast, using geopressured brines offers an environmentally
clean process (Negus-de Wys, 1989).
The potential impacts and feasibility appear very high. Industry is
proposing a demonstration project. Accordingly, the INEL is preparing a
feasibility study.
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