| This study, conducted by BP Corporation North America Inc. and the Underground Storage Tank (UST) Programs of U.S. EPA Regions 4 and 5, was undertaken to determine whether measurements of groundwater parameters obtained using direct-push wells are comparable to those obtained from conventional monitoring wells. Direct-push monitoring wells contained no filter pack and were pushed into the subsurface; conventional monitoring wells contained filter packs and were installed with typical drilling and completion methods. The measured parameters were groundwater levels, chemical concentrations (BTEX, MTBE, TSS, and naphthalene), hydraulic conductivity, and natural attenuation (geochemistry) parameters. The study was conducted at two sites in Ohio and two sites in Georgia and they were chosen so there was a wide-range of soils, conductivities, and concentrations. |