BSI was contracted to eliminate annular pressure on the 7” intermediate casing on a well in Pennsylvania. Prior to treatment, pressure was 17 psi. The well was prepared by cutting two 360 degree notches just above an existing cement plug at 600’, setting 2-7/8” tubing just above the top of cement, and placing a packer just above the notches.
Seven injection stages were run over a 36-hour period.
Pressure was raised incrementally in the 1st stage to 600 psi. Around 45 minutes into pumping a channel was opened allowing a significant volume of fluids to be injected. Pressure was held steady throughout the 2nd and 3rd stages, during which time the flow rate fell steadily. The well was then shut in at pressure overnight to allow calcium carbonate crystals to continue to grow, filling the leakage pathways with new minerals.
Injection resumed the next morning at 600 psi. Over the next four stages, the flow rate experienced a steady and significant decrease, implying leaks had been successful sealed. Pumping concluded late in the day, allowing the well to be shut in at pressure overnight once again.
The flow rate began at 1.678 gpm in the 1st stage and ended at 0.021 gpm at the conclusion of the 7th stage, with a total of 137 gal injected. This constituted a 98.7% decrease in injectivity, implying significant sealing.
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