Perth Basin oil and gas explorer Norwest Energy said that milling operations have successfully removed cement from within the 5-1/2-inch casing from a depth of 2,420 m to just above the casing float collar.
This follows the company’s announcement on 27 September, where it reported that during casing cementing operations, the cement was not displaced into the annulus due to a suspected wiper plug held up in the casing hanger.
This resulted in cement remaining within the 5-1/2-inch production casing, with only minimal cement in the production annulus.
Subsequent to the last announcement, Norwest has confirmed that a significant amount of cement was displaced into the 5-1/2-inch casing annulus.
The hole is currently being conditioned before a wireline cement bond log can be run to determine the extent and integrity of the cement in the annulus.
The results of the bond log will determine the forward program for any further remediation activities as the well progresses towards completion.
A further announcement will provide a summary of that program as soon as details are know, the company said.
The Ensign 970 rig has remained on location for the milling operations, and Norwest said the resulting delay to well completion is not expected to materially affect the timing of production testing of the Kingia Sandstone reservoir.
At this stage, costs associated with drilling the Lockyer Deep-1 well have remained with the joint venture (JV) authorisation for expenditure of around $14.5 million.
Necessary additional time and equipment for completion will result in incremental costs to the JV that are not expected to exceed $5 million.
Norwest managing director Ian Smith said on 27 September that the company remained on track to test the Kingia reservoir in the fourth quarter of this year.
“While this operational event is a frustration, we do not anticipate a material delay to the production testing,” Smith said.
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