Vasthu is all about science.
Generally people will dig bore /well in the North East corner because from bore/Well some gases will be release. 80 to 90 % wind will flow from southwest (Nairuthi) to northeast (eshan). So Gases will go out of house instead of getting in to the house. If gases release from bore, enter in to house then it will show ill effect on the people living in that house.
I have given you a scientific reason behind it. Its all up to you to take decision.