Helix Exploration (AIM:HEX) has completed the Ollie #1 well at its Rudyard helium project in northern Montana, reaching a total depth of 6,311 ft in 20 days with casing set and cemented to surface.
The helium producer said mudlog readings during drilling hit 4,800 parts per million (0.48%) helium, the highest recorded at any Rudyard well and well above the field's previous high of 1,200 ppm.
Ollie #1 sits in the Northern Dome of the Rudyard field, about one mile north of the Weil #1 well, and is intended to become the fourth production well feeding the site's pressure swing adsorption (PSA) plant.
Helix completed the well ahead of schedule and under budget, a result it attributes to owning its drilling rig outright following its acquisition of Treasure State Drilling and its Cardwell KB-150 rig earlier this year.
"We are delighted to complete Ollie #1 under budget and in record time, a benefit of the Company owning its own drilling equipment," said Bo Sears, chief executive, adding that the real-time helium readings from drilling fluid were "the highest I have encountered in my career to date".
Mudlog readings offer an early indication of helium presence but do not necessarily translate into higher recoverable volumes, the company cautioned, noting that Ollie #1 will require detailed gas composition analysis and flow testing to assess its commercial potential.
Helix is now working to contract a workover rig to perforate and test the target intervals, which Sears said could happen within two to three weeks given tight regional availability, with mobilisation expected by 31 October.
Subject to flow testing results, the company plans to tie Ollie #1 into the existing gathering system at Weil #1 and connect it to the PSA plant within current membrane capacity.
Helix has also designated Ross #1, another well on the Rudyard structure, as the next well in its production expansion programme, with spudding possible by 31 October pending approval from the Montana Board of Oil and Gas Conservation.