An accurate understanding of borehole geometry is critical for proper design of primary cement jobs for shallow, large hole sections drilled in deepwater blocks of the Gulf of Mexico (GOM). This drilling environment is characterized by weak, unconsolidated formations, narrow tolerances between pore and fracture gradients, shallow water now hazards, and abrupt variations in downhole pore pressures. Large hole size and the deepwater drilling environment make use of wireline calipers impractical. Traditional logging-while-drilling (LWD) approaches for acquiring borehole data are also ineffective for these shallow hole sections because of borehole size. Recent developments in a resistivity-at-the-bit (RAB) tool show great promise for effectively addressing this problem.