More carbon under the rug

Researchers at Lawrence Livermore National Laboratory show how artificially created calcium bicarbonate, using limestone, can be used to lock up carbon in the ocean. This is a naturally occuring process, but it takes 5,000-10,000 years. This method would supposedly have fewer negative effects compared with schemes such as injecting CO2 directly into the ocean or fertilising the ocean with iron. It is envisaged that this process would be hooked up to a CO2 producing powerplant.
New Scientist points out (Issue No. 2321) that a large quantity of limestone would be required and this would probably have to be strip mined.