Well AA was spud on December 2008 and drilled to 16,432 ft (side track-2) in the Eocene formation. In 6" hole, 5" liner was set from 15,498 ft – 16,426 ft. During circulation prior to cementing job, the circulation ceased due to plugging and the circulation had to be aborted. In order to find out the reason for plugging cement evaluation log was carried out, which showed strong barite settling behind bottom section of 5" liner.

After extending 7" liner to surface, 92 ft (selective) of Sakesar / Nammal & Patala formations were perforated. While homogenizing mud, gas cut was observed, subsequently mud weight was increase to 17.1 ppg. 7" permanent packer with 2-7/8" tail (207’ long) was set at 15,424 ft. Well was completed with 3 ½" tubing along with gauge adaptor and PTSV.

15K Flow head was installed on April 2010. Coiled tubing was run and 17.1 ppg mud in tubing was displaced with 12 ppg to 7,500 ft, observed no flow. Lowered CT down to 10,000 ft and hole volume was displaced with 9 ppg gel when the well started to flow strong gas. The onsite compositional analysis showed 7% H2S. In order to meet the critical differential on 7" casing below the packer, the choke was reduced to 6/64" (WHP 5000-5150 Psi). CT was pulled out of hole. The well was S/I and the WHSIP increased to 10,162 psi. In view of high shut in pressure and the presence of high H2S concentration it was deemed prudent to discontinue the test. Therefore the well was shut-in from down hole PTSV.

The tubing string above the PTSV was displaced with 18.2 ppg mud using CT. The tubing along with DGA was pulled out (Max BHP 13,102 Psi and Max BHT 308 °F at 15324 ft). After milling permanent packer, homogenized 18.2 ppg mud against perforations. 5" bridge plug was set at 15,632 ft, capped with cement plug (top of cement at 15136 ft). RIH 3 ½" open ended tubing to 13,158 ft. N/D BOP and N/Up X-Mas tree. Well temporarily suspended and rig released on May 2010.

On March 2011 the company decided to bring work over rig to re-complete the well with a new completion string. The integrity of the liner and casing was in question. Some pressure build up was also monitored in annulus between casings. Pipe inspection was needed to evaluate integrity of the liner and casing. The need to monitor the condition of second pipe behind first pipe filled with heavy mud weight (17.2 ppg), eliminated the option of using standard acoustic pipe inspection tool.

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