The first component of the ZAP-C 3 system is designed to accomplish the dissolution of CO2 into neutral water giving an acidic CO2 solution, which is confirmed by the reduction of the pH from 7 to 3.8 and the measurable difference in TOC, i.e., 8.2 and 13.4 ppm before and after exposure to CO2, respectively. The acidic solution washes through the mineral reagent (BOS slag) converting it to a volumetrically stable material by removal of "free" calcium . Analysis of the solutions during both components of the ZAP-C3 process are shown in Table . After precipitation 6.9 0.01(1) 10.0(1)