After drilling the intermediate section of a wellbore to 9,000 ft TVD, completing the casing running and cementing operations, the same mud system is going to used to drill the next hole section. However, the density of the water-based mud must increase from 11 ppg to 12.5 ppg while the total mud volume needs to remained constant, 800 bbl. The solid concentration, solid = 13.8 ppg, in the current mud is 6% and needs to be lowered to 3% in the new mud system.

How much water is required to complete the task?

How much mud needs to be discarded?

What is the density of water in the downhole condition if the surface temperature and the geothermal gradient are

70F and 0.01 F/ft, respectively?