Well, I don't know if fly ash is available in your area. This is the least expensive alternative. You should use clean type F fly ash with a free Carbon content of less than 4%. Fly ash with Carbon content of more than 4% will work as long as you are not using plasticizers or air entraining...
The white stuff is calcium hydoxide and can be eliminated with a reduced permeability in concrete. You can use pozzolans such as silica fume or fly ash to reduce the permeability of concrete. A reduced water to cement ratio will help as well. Super plasticizers can help to acheive the...
There is an inexpensive program called PRODUCTIVITY TOOLS for Geotechnical Engineers developed by Prototype Engineering, Inc. in Massachusetts Tel No. is 781-729-2363.
Good Luck