fracture gradient perforation friction wellbore friction and tortuosity using methods known in the art once the isip is read and the number of open holes are computed the operator pumps approximately 5000 gallons of treated water into the casing at 35 bpm along with the number of ball sealers 197 in this example needed to plug the holes in the first intermediate zone once the ball sealers are seated the fluid should be able to be diverted into the next intermediate zone having the next higher stress or fracture gradient approximately 15 000 gallons of treated water is then pumped into the casing at a rate of 65 bpm in order to initiate and create a fracture in the next intermediate zone at this point the operator again steps the rate down to zero and reads the isip and again computes the fracture gradient if the fracture gradient differs by at least 0 02 psi ft then the operator knows that diversion has indeed occurred the operator then continues pumping a sufficient volume of treated water 21 000 gallons in this case into the intermediate zone to initiate fracture and overcome any tortuosity or near wellbore friction the operator again steps the rate down to zero reads the isip and again computes the fracture gradient to confirm the rock properties the operator has to decrease the pump rate to zero to surge the balls anyway by performing the step down and obtaining a 3 rd isip which is the 2 nd isip on the zone of higher stress the operator can determine how much net pressure was gained from pumping the additional 21 000 gallons of fluid into the formation this allows the operator to determine by.