During the last quarter of 2004, the PL 198 joint venture tested three new well completion designs in Tipton West Pilot-9, 11 and 13. As expected each new completion has responded differently, according to Comet Ridge.

“Two of the new completions – Tipton West Pilot-9 and 13 – resulted in a doubling to tripling of well productivity respectively over the original TWP well designs,” the company said in a statement.

TWP-9 is a 600m step-out south of the pilot. The well averaged over 500 barrels of water per day and has flowed gas up to 35,000 cfd. Given the extent of the step-out, this is an encouraging early result, according to Comet Ridge.

TWP-13 is a 300m step out south-east of the pilot. The well has averaged close to 1,000 bwpd and had a peak gas rate of 165,000 cfd just prior to being shut in for a workover.

“The TWP-13 completion has the highest productivity of any well in the pilot,” Comet Ridge said.

“Higher productivity corresponds to high gas rates. It is expected with further dewatering that TWP-13 will be a significant gas producer.”

The third completion style was run in TWP-11, which did not have the same productivity as the other well due to mechanical problems. But gas rates of up to 100,000 cfd have occurred.

“It is felt that the gas rates in this well will continue to rise but at a slower rate to those in TWP-9 and 13,” Comet Ridge said.

The well design for the best performing well, TWP-13, under-reams the Juandah coal seams and runs slotted casing. This has become the new standard completion for the Surat Basin, according to Comet Ridge.

“Similar completions in [Queensland Gas Company’s] Berwyndale South and Argyle fields are meeting with success and record productivity increases,” the firm said.

“It is expected that similar results will be occurring in the Tipton West Pilot early in 2005.”

Despite these initial encouraging results, a recent significant increase in the CBM activity has slowed down the assessment of TWP. The lack of promptly available workover rigs to change out pumps and tubing has resulted in some wells being shut in, waiting on a workover rig, for a few weeks at a time, according to Comet Ridge.

“This lag effect in optimally operating the pilot has resulted in a in a slower than anticipated gas production increase,” the company said.

To increase the pressure drawdown in the pilot, boost gas production and get back on track for 2006 gas delivery, the PL 198 JV has agreed drill another two new wells –TWP-14 and 15, which will incorporate a further fine tuning of the completion model used in TWP-13.

These new wells were spudded early this month and are expected to be very shortly completed simultaneously with a round of workovers.

The joint venture is continuing to provide production information from the new wells to NSAI for incorporation into an updated reserves certification report. With the delays caused in securing workover rigs the partners now expect to receive updated reserves by the end of the first quarter of 2005.

Meanwhile development planning is proceeding on a work program in the second half of the year.

“Well designs are firming and further progress has been made on the pipeline and infrastructure layouts,” Comet Ridge said.

Interests at Tipton West are Arrow Energy (80%) and Comet Ridge (20%).