to 1000 psi where it is maintained to identify any leaks in this case no leaks were detected commencing at 9 34 the tubing is pressurized to 6500 psi and maintained until 10 10 to confirm no leaks thereafter the tca line pressure was bled off to zero and diesel oil was introduced into the tca to displace the water and pressurized to about 300 psi at 10 20 the tubing pressure is increased and the tca pressure is increased to 850 psi during the pressurizing of the tubing the tca is isolated but the tca pressure is monitored in a data acquisition unit in order to assure safe operation should the tca pressure begin to drop significantly the procedure will be interrupted and tubing pressure reduced until the cause of the fault is determined and corrected water rather than diesel was used for pumping to ensure safety since diesel might be subjected to ignition conditions during injection injection was started by pressurizing the pump discharge line up to 7500 psi while pressure cycling for three times i e the pressure was increased to 7500 psi and bled off to lower the pressure the tca pressure was observed to increase because of the increase in tubing pressure by 11 00 the tubing pressure was increased to 8000 psi at the pump discharge and was thereafter bled to 0 in order to initiate a higher differential pressure in the subsequent pressure stroke the tca pressure was maintained at about 850 psi at 11 03 the actual differential line pressure in the tubing reached 2200.