A METHOD FOR DESIGNING DETECTION MONITORING NETWORKS IN LAYERED AQUIFERS WITH NONUNIFORM FLOW

An integer programming method was devised to locate detection monitori ng wells in layered aquifers. The method is applicable to aquifers wit h nonuniform groundwater flow, and it does not require that a complian ce boundary be linear or perpendicular to the direction(s) of groundwa ter flow. In each layer, monitoring sites are defined along curvilinea r transects that parallel equipotential lines. The model can be formul ated to allocate wells to the transect with the highest detection effi ciency, or to establish multiple lines of defense against contaminant migrating to a compliance boundary. Detection efficiencies of alternat ive monitoring transects are calculated from parameters obtained via n umerical modeling of contaminant transport. These parameters include t he narrowest plume that could traverse a monitoring transect, and the zone width of potential contaminant migration at the transect. Problem formulations are compact, and computational requirements are low rela tive to alternative approaches for designing detection monitoring netw orks in aquifers. An application to a glacial outwash aquifer demonstr ates the utility of the method. (C) 1996 Academic Press Limited