cooling leaks

I have a 2006 VW Passat 2.oL Turbo. It leaks cooling under the passenger side. The leak comes right from the crankshaft location. Thea leak is huge (1 gallon every 2 days) What could it be the problem? It is not from tubes/hoses..... How much would you charge for water pump + timing belt kit replacement? With your and/or my parts....... This is my spare car, but I want to have it fixed.