The potential for carbon dioxide (CO2) sequestration via engineered chemical sinks is investigated using a three dimensional chemical transport model (CTM). Meteorological and chemical constraints for flat or vertical systems that would absorb CO2 from the atmosphere, as well as an example chemical system of calcium hydroxide (Ca(OH)(2)) proposed by Elliott et al. [Compensation of atmospheric CO2 buildup through engineered chemical sinkage, Geophys. Res. Lett. 28 (2001) 1235] are reviewed. The CTM examines land based deposition sinks, with 4degrees x 5degrees latitude/longitude resolution at various locations, and deposition velocities (nu). A maximum uptake of similar to20 Gton (10(15) g) C yr(-1) is attainable with nu > 5 cm s(-1) at a mid-latitude site. The atmospheric increase of CO2 (3 Gton yr(-1)) can be balanced by an engineered sink with an area of no more than 75,000 km(2) at nu of 1 cm s(-1). By building the sink upwards or splitting this area into narrow elements can reduce the active area by more than an order of magnitude as discussed in Dubey et al. [31].